author desharna
Mon, 02 Oct 2023 11:28:23 +0200
changeset 78737 183a28459663
parent 78729 fc0814e9f7a8
permissions -rw-r--r--

Isabelle NEWS -- history of user-relevant changes

(Note: Isabelle/jEdit shows a tree-view of the NEWS file in Sidekick.)

New in this Isabelle version

*** System ***

* Isabelle/Scala and derived Scala tools now use the syntax of Scala
3.3, instead of 3.1. This is the "-old-syntax" variant (Java-like) as
before, not "-new-syntax" (Python-like). Minor INCOMPATIBILITY.

*** ML ***

* ML antiquotation "try" provides variants of exception handling that
avoids accidental capture of physical interrupts (which could affect ML
semantics in unpredictable ways):

  \<^try>\<open>EXPR catch HANDLER\<close>
  \<^try>\<open>EXPR finally HANDLER\<close>

See also the implementations Isabelle_Thread.try_catch / try_finally /
try. The HANDLER always runs as uninterruptible, but the EXPR uses the
the current thread attributes (normally interruptible). Various examples
occur in the Isabelle sources (.ML and .thy files).

* Isabelle/ML explicitly rejects 'handle' with catch-all patterns.
INCOMPATIBILITY, better use \<^try>\<open>...\<close> with 'catch' or 'finally', or
as last resort declare [[ML_catch_all]] within the theory context.

*** HOL ***

* Mirabelle:
  - Removed proof reconstruction from "sledgehammer" action; the related option
  "proof_method" was removed. Proof reconstruction is supported directly
  by Sledgehammer and should be used instead. For more information, see
  Sledgehammer's documentation relating to "preplay_timeout". INCOMPATIBILITY.

New in Isabelle2023 (September 2023)

*** General ***

* Toplevel results --- like declared consts and proven theorems --- are
printed as regular "writeln" message instead of "state", which is no
specifically for proof states. This affects Isabelle/jEdit panels for
Output vs. State in particular.

* Session build dependencies (sources and heaps) are now recorded in
more details, with one SHA1 digest per file and a symbolic version of
the file name -- similar to the Unix command-line tool "sha1sum". For
portability of results, well-known directory names are folded into path
variables according to cumulative "isabelle_directory" declarations in
etc/settings (user projects may add to that). See also "isabelle getenv
ISABELLE_DIRECTORIES" for the effective result, which is used by the
Isabelle/Scala function isabelle.File.symbolic_path() for its
first-match policy in reverse order.

* ML heap usage and stored heap size has been significantly reduced,
especially for applications with a lot 'locale' or 'class' context
switches, e.g. "definition (in loc)". The shrink factor is usually in
the range 1.1 .. 2.0, but a factor 2 .. 25 has been seen as well. This
often allows big applications to return to the "small" 64_32 memory
model with its hard limit of 16 GiB, and thus reduce the heap size by
another factor 1.8.

* The special "of_class" introduction rule for 'class' definitions has
been renamed from "class.NAME.of_class.intro" to "NAME.intro_of_class"
(where NAME is the name specification of the class). E.g. see the HOL

  class.preorder.of_class.intro  ~>  preorder.intro_of_class
  class.order.of_class.intro  ~> order.intro_of_class

* The Eisbach 'method' command now takes an optional description for
display with 'print_methods', similar to the 'method_setup' command.

* Experimental support for distributed build clusters, based on SSH and
PostgreSQL. Example for 3 nodes (local, host1, host2):

    isabelle build -a -j2 -o threads=8 \
      -H host1:jobs=2,threads=8
      -H host2:jobs=4:threads=4,numa,shared

Like the "isabelle sync" tool, this requires a proper Isabelle
repository clone (e.g. via "isabelle/Admin/init -r Isabelle2023").

The build database server needs to be specified for each remote node in
$USER_HOME/.isabelle/build_cluster (according to option

See also "isabelle build_process -?" and "isabelle build_worker -?".

*** Document preparation ***

* Support for interactive document preparation in PIDE, notably via the
Isabelle/jEdit Document panel.

* Various well-known LaTeX styles are included as Isabelle components,
with demo documents in the regular Isabelle "doc" space:

  - Easychair as session "Demo_Easychair" / doc "demo_easychair"
  - EPTCS as session "Demo_EPTCS" / doc "demo_eptcs"
  - FoilTeX as session "Demo_FoilTeX" / doc "demo_foiltex"
  - Dagstuhl LIPIcs style as session "Demo_LIPIcs" / doc "demo_lipics"
  - Springer LaTeX LNCS style as session "Demo_LLNCS" / doc "demo_llncs"

* Support for more "cite" antiquotations, notably for \nocite and
natbib's \citet / \citep. The antiquotation syntax now supports
control-symbol-cartouche form, with an embedded argument:
\<^cite>\<open>arg\<close>. The embedded argument syntax supports both the optional
and mandatory argument of the underlying \cite-like macro.


  \<^cite>\<open>\<open>\S1.2\<close> in "isabelle-system"\<close>
  \<^cite>\<open>"isabelle-system" and "isabelle-jedit"\<close>

The old antiquotation option "cite_macro" has been superseded by
explicit syntax: \<^cite>\<open>\<dots> using macro_name\<close>.

The command-line tool "isabelle update -u cite" helps to update former
uses of LaTeX \cite commands and old-style @{cite "name"} document

*** HOL ***

* Sledgehammer:
  - Added an inconsistency check mode to find likely unprovable
    conjectures. It is disabled by default and can be controlled using
    the 'falsify' option.
  - Added an abduction mode to find likely missing hypotheses to
    conjectures. It works only with the E prover. It is disabled by
    default and can be controlled using the 'abduce' option.

* Metis:
  - Made clausifier more robust in the face of nested lambdas.

* Command "try0":
  - Add proof method "order".

* 'primcorec': Made the internal tactic more robust in the face of
nested corecursion.

* Theory "HOL.Map":
  - Map.empty has been demoted to an input abbreviation.
  - Map update syntax "_(_ \<mapsto> _)" now has the same priorities
    as function update syntax "_(_ := _)". This means:
    1. "f t(a \<mapsto> b)" must now be written "(f t)(a \<mapsto> b)"
    2. "t(a \<mapsto> b)(c \<mapsto> d)" must now be written
       "t(a \<mapsto> b, c \<mapsto> d)" or
       "(t(a \<mapsto> b))(c \<mapsto> d)".
    Moreover, ":=" and "\<mapsto>" can be mixed freely now.
    Except in "[...]" maps where ":=" would create a clash with
    list update syntax "xs[i := x]".

* Theory "HOL.Fun":
  - Renamed lemma inj_on_strict_subset to image_strict_mono.

* Theory "HOL.Euclidean_Division" renamed to "HOL.Euclidean_Rings";
  "euclidean division" typically denotes a particular division on
  integers.  Minor INCOMPATIBILITY.

* Theory "HOL.Finite_Set"
  - Imported Relation instead of Product_Type, Sum_Type, and Fields.
  - Added lemmas.

* Theory "HOL.Relation":
  - Imported Product_Type, Sum_Type, and Fields instead of Finite_Set.
  - Added predicates irrefl_on and irreflp_on and redefined irrefl and
    irreflp to be abbreviations. Lemmas irrefl_def and irreflp_def are
    explicitly provided for backward compatibility but their usage is
    discouraged. Minor INCOMPATIBILITY.
  - Added predicates sym_on and symp_on and redefined sym and symp to be
    abbreviations. Lemmas sym_def and symp_def are explicitly provided
    for backward compatibility but their usage is discouraged. Minor
  - Added predicates asym_on and asymp_on and redefined asym and asymp
    to be abbreviations. INCOMPATIBILITY.
  - Added predicates antisym_on and antisymp_on and redefined antisym
    and antisymp to be abbreviations. Lemmas antisym_def and
    antisymp_def are explicitly provided for backward compatibility but
    their usage is discouraged. Minor INCOMPATIBILITY.
  - Added predicates trans_on and transp_on and redefined trans and
    transp to be abbreviations. Lemmas trans_def and transp_def are
    explicitly provided for backward compatibility but their usage is
    discouraged. Minor INCOMPATIBILITY.
  - Renamed wrongly named lemma totalp_on_refl_on_eq to
    totalp_on_total_on_eq. Minor INCOMPATIBILITY.
  - Strengthened (and renamed) lemmas. Minor INCOMPATIBILITY.
      antisym_converse[simp] ~> antisym_on_converse[simp]
      order.antisymp_ge[simp] ~> order.antisymp_on_ge[simp]
      order.antisymp_le[simp] ~> order.antisymp_on_le[simp]
      preorder.asymp_greater[simp] ~> preorder.asymp_on_greater[simp]
      preorder.asymp_less[simp] ~> preorder.asymp_on_less[simp]
      preorder.irreflp_greater[simp] ~> preorder.irreflp_on_greater[simp]
      preorder.irreflp_less[simp] ~> preorder.irreflp_on_less[simp]
      preorder.transp_ge[simp] ~> preorder.transp_on_ge[simp]
      preorder.transp_gr[simp] ~> preorder.transp_on_greater[simp]
      preorder.transp_le[simp] ~> preorder.transp_on_le[simp]
      preorder.transp_less[simp] ~> preorder.transp_on_less[simp]
      reflp_equality[simp] ~> reflp_on_equality[simp]
      sym_converse[simp] ~> sym_on_converse[simp]
      trans_converse[simp] ~> trans_on_converse[simp]
  - Added lemmas.

* Theory "HOL.Transitive_Closure":
  - Strengthened (and renamed) lemmas. Minor INCOMPATIBILITY.
      antisym_reflcl[simp] ~> antisym_on_reflcl[simp]
      reflp_rtranclp[simp] ~> reflp_on_rtranclp[simp]
      symp_symclp[simp] ~> symp_on_symclp[simp]
      trans_reflclI[simp] ~> trans_on_reflcl[simp]
  - Added lemmas.

* Theory "HOL.Wellfounded":
  - Added lemmas.

* Theory "HOL-Library.FSet":
  - Redefined fmember as an abbreviation based on Set.member.
  - Redefined notin_fset as an abbreviation based on Set.not_member and
    renamed to not_fmember. Minor INCOMPATIBILITY.
  - Redefined fBall and fBex as abbreviations based on Set.Ball and Set.Bex.
  - Removed lemmas. Minor INCOMPATIBILITIES.
  - Added lemmas.

* Theory "HOL-Library.BigO" is obsolete and has been moved to
  "HOL-ex.BigO" (it corresponds to "HOL-Metis_Examples.Big_O").

* Theory "HOL-Library.Multiset":
  - Strengthened lemmas. Minor INCOMPATIBILITIES.
  - Used transp_on and reorder assumptions of lemmas bex_least_element
    and bex_greatest_element. Minor INCOMPATIBILITIES.
  - Added lemmas.

* Theory "HOL-Library.Multiset_Order":
  - Added lemmas.

* Session "HOL-Algebra": new theories "HOL-Algebra.SimpleGroups" and
"HOL-Algebra.SndIsomorphismGrp" (second isomorphism theorem for groups),
by Jakob von Raumer.

* Session "HOL-Analysis":
  - Some results reformulated to use f \<in> A\<rightarrow>B rather than f`A \<subseteq> B,
    INCOMPATIBILITY, use image_subset_iff_funcset to fix.
  - Some results reformulated to use X = trivial_topology rather than
    topspace X = {}, INCOMPATIBILITY, use null_topspace_iff_trivial to fix.
  - Imported the HOL Light abstract metric space library and numerous
    results in abstract topology (1200+ lemmas).
  - New material on infinite sums and integration, due to Manuel Eberl
    and Wenda Li.

* Session "Mirabelle": Added session name to output directory structure.

*** ML ***

* ML antiquotation \<^if_none>\<open>expr\<close> inlines a function (fn SOME x => x
| NONE => expr); this is a non-strict version of the regular function
"the_default". Both are particularly useful with the |> combinator.

* Improved implementations and signatures of functor Table() and
corresponding functor Set().

  - Specific Set().T supersedes Table().set = unit table, with concrete
    instances Intset, Symset, Termset etc.

  - Data representation is more compact than before, approx. 85% .. 110%
    of a plain list (e.g. see structure AList or Ord_List, respectively).

  - The new "size" operation works with constant time complexity and
    minimal space overhead: small structures have no size descriptor.

* Operations ML_Heap.sizeof1 and ML_Heap.sizeof determine the object
size on the heap in bytes. The latter works simultaneously on multiple
objects, taking implicit sharing of values into account. Examples for
the default 64_32 platform (4 bytes per machine word):

  val s = "aaaabbbbcccc";
  val a = ML_Heap.sizeof1 s;
    (*20: 2 words descriptor + 3 words content*)
  val b = ML_Heap.sizeof [s, s];
    (*20: shared values without list structure*)
  val c = ML_Heap.sizeof1 [s, s];
    (*44 = 20 + 24: shared values + 2 * 3 words per list cons*)

* Operations for Zstd compression (via Isabelle/Scala):

  Zstd.compress: Bytes.T -> Bytes.T
  Zstd.uncompress: Bytes.T -> Bytes.T

*** System ***

* The command-line tool "isabelle build" now supports option -A to
include AFP as directory, without selecting any sessions yet.

* The command-line tool "isabelle profiling" produces per-session
statistics from ML heap images. Command-line options are similar to
"isabelle build". Output is in CSV format, which can be opened by common
spreadsheet applications (e.g. LibreOffice Calc).

* The command-line tool "isabelle update" is now directly based on
"isabelle build" instead of "isabelle dump". Thus it has become more
scalable, and supports most options from "isabelle build". Partial
builds are supported as well, e.g. "isabelle update -n -a".

* The command-line tool "isabelle log" has been renamed to "isabelle
build_log", to emphasize its relation to "isabelle build".

* The command-line tool "isabelle build_docker" has been renamed to
"isabelle docker_build", to emphasize its non-relation to "isabelle

* System options "context_theory_tracing" and "context_proof_tracing"
store information about persistent context values (ML types theory,
local_theory, Proof.context). This may reveal "memory leaks" in
Isabelle/ML infrastructure or user tools, typically due to the lack of
Thm.trim_context when thm values are stored as theory data.

Below is a minimal example for Isabelle/ZF. The idea is to build a clean
heap image with the above options enabled, and inspect the resulting ML
heap later:

  isabelle build -o context_theory_tracing -o context_proof_tracing -b -c ZF
  isabelle process -l ZF -e "Session.print_context_tracing (K true)"

An alternative to "isabelle process -l ZF" is "isabelle jedit -l ZF"
with the subsequent Isar commands:

  print_context_tracing ZF.Nat ZF.Int  \<comment> \<open>restriction to theories\<close>

* The "rsync" tool has been bundled as Isabelle component, with uniform
version and compilation options on all platforms. This allows to use
more recent options for extra robustness, notably "--secluded-args"
(formerly "--protected-args"). Option -P of "isabelle hg_sync" and
"isabelle sync" has been eliminated accordingly.

* Remote SSH host of "isabelle hg_sync" and "isabelle sync" now works
via options -s, -p, -u. The TARGET argument is a plain file-system path
in Isabelle notation, no longer an rsync target (host:directory). Minor
INCOMPATIBILITY of command-line syntax.

* System option "build_through" determines if session builds should
observe dependency of options that contribute to the formal content.
This is specified via option tags given in etc/options (e.g. see
"isabelle options -l -t content,document"). A change of such options
causes a fresh build. For example:

  isabelle build FOL
  isabelle build -o show_types FOL  # unchanged, no depency on options
  isabelle build -o build_thorough -o show_types FOL  # changed
  isabelle build -o build_thorough FOL  # changed

* System option "build_pide_reports" has been discontinued: it coincides
with "pide_reports".

* System option "ML_process_policy" has been renamed to
"process_policy", as it may affect other processes as well (notably in
"isabelle build").

* The command-line tools "isabelle dotnet_setup" and "isabelle dotnet"
support the Dotnet platform (.NET), which includes Fsharp (F#). This
works uniformly on all Isabelle OS platforms, even as cross-platform
installation: "isabelle dotnet_setup -p linux_arm,linux,macos,windows".


  isabelle dotnet_setup
  isabelle dotnet fsi
  > 1 + 1;;
  > #quit;;

* The headless PIDE server (e.g. command-line tool "isabelle server")
now observes the option "show_states" as given in the server command
"session_start". If enabled, the server command "use_theories" will
expose proof state output via its "messages" field.

* Isabelle server command "session_build" no longer supports the
"verbose" flag. Instead, all messages are shown unconditionally, while
the property {"verbose": bool} indicates whether the result is meant to
depend on verbose mode.

* Isabelle/Scala provides generic support for XZ and Zstd compression,
via Compress.Options and Compress.Cache. Bytes.uncompress automatically
detects the compression scheme.

* File.set_executable in Isabelle/Scala has changed its mandatory "flag"
to optional "reset", which opposite polarity. INCOMPATIBILITY.

* Update to GHC stack 2.9.3 with support for arm64-linux.

* Isabelle/Scala supports TOML (Tom's Obvious, Minimal Language), which
aims to be a minimal configuration file format. See also

* Update of Poly/ML with more robust support for ARM64 platform, notably
Apple Silicon M1/M2.

New in Isabelle2022 (October 2022)

*** General ***

* The instantiation of schematic goals is now displayed explicitly as a
list of variable assignments. This works for proof state output, and at
the end of a toplevel proof. In rare situations, a proof command or
proof method may violate the intended goal discipline, by not producing
an instance of the original goal, but there is only a warning, no hard

* Session ROOT files support 'chapter_definition' entries (optional).
This allows to associate additional information as follows:

  - "chapter_definition NAME (GROUPS)" to make all sessions that belong
  to this chapter members of the given groups

  - "chapter_definition NAME description TEXT" to provide a description
  for presentation purposes

* Old-style {* verbatim *} tokens have been discontinued (legacy feature
since Isabelle2019). INCOMPATIBILITY, use \<open>cartouche\<close> syntax instead.

*** Isabelle/jEdit Prover IDE ***

* Command 'print_state' outputs a plain message, i.e. "writeln" instead
of "state". Thus it is displayed in the Output panel, even if the option
"editor_output_state" is disabled.

*** Isabelle/VSCode Prover IDE ***

* VSCodium, an open-source distribution of VSCode without MS telemetry,
has been bundled with Isabelle as add-on component. The command-line
tool "isabelle vscode" automatically configures it as Isabelle/VSCode
and starts the application. This includes special support for the
UTF-8-Isabelle encoding and the corresponding Isabelle fonts.

* Command-line tools "isabelle electron" and "isabelle node" provide
access to the underlying technologies of VSCodium, for use in other
applications. This essentially provides a freely programmable Chromium
browser engine that works uniformly on all platforms.


  URL="" isabelle electron \
    --app="$(isabelle getenv -b ISABELLE_HOME)"/src/Tools/Electron/test

*** HTML/PDF presentation ***

* Management of dependencies has become more robust and accurate,
following the session build hierarchy, and the up-to-date notion of
"isabelle build". Changed sessions and updated builds will cause new
HTML presentation, when that is enabled eventually. Unchanged sessions
retain their HTML output that is already present. Thus HTML presentation
for basic sessions like "HOL" and "HOL-Analysis" is produced at most
once, as required by user sessions.

* HTML presentation no longer supports README.html, which was meant as
add-on to the index.html of a session. Rare INCOMPATIBILITY, consider
using a separate theory "README" with Isabelle document markup/markdown.

* ML files (and other auxiliary files) are presented with detailed
hyperlinks, just like regular theory sources.

* Support for external hyperlinks (URLs).

* Support for internal hyperlinks to files that belong formally to the
presented session.

*** HOL ***

* HOL record types: new simproc that sorts update expressions, guarded
by configuration option "record_sort_updates" (default: false). Some
examples are in theory "HOL-Examples.Records".

* More explanations on the new, verified order prover for partial and
linear orders, which first appeared in Isabelle2021-1.

The order prover rearranges the goal to prove False, then retrieves
order literals (i.e. x = y, x <= y, x < y, and their negated versions)
from the premises and finally tries to derive a contradiction. Its main
use case is as a solver to the Simplifier, where it e.g. solves premises
of conditional rewrite rules.

The new prover (src/Provers/order_tac.ML) replaces the old prover
(src/Provers/order.ML) and improves upon the old one in several ways:

  - The completeness of the prover is verified in Isabelle (see the ATVA
    2021 paper "A Verified Decision Procedure for Orders in

  - The new prover is complete for partial orders.

  - The interface to register new orders was reworked to reduce

The prover has two configuration attributes that control its behaviour:

  - order_trace (default: false) to enable tracing for the solver.

  - order_split_limit (default: 8) to limit the number of order literals
    of the form ~ x < y that are passed to the solver since those lead
    to case splitting and thus exponential runtime. This only applies to
    partial orders.

The prover is agnostic to the object-logic, but the default setup is for
HOL: see theory HOL.Orderings with ML structure HOL_Order_Tac. The
structure allows us to register new orders with the functions
HOL_Order_Tac.declare_order and HOL_Order_Tac.declare_linorder. Using
these functions, we register the orders of the type classes order and
linorder with the solver. If possible, one should instantiate these type
classes instead of adding new orders to the solver. One can also
interpret the type class locale as in src/HOL/Library/Sublist.thy, which
contains e.g. the prefix order on lists.

The proof method "order" invokes the prover in a standalone fashion.

The diagnostic command 'print_orders' shows all orders known to the
prover in the current context.

* Meson: added support for polymorphic "using" facts. Minor

* Moved auxiliary computation constant "divmod_nat" to theory
"HOL.Euclidean_Division". Minor INCOMPATIBILITY.

* Renamed attribute "arith_split" to "linarith_split". Minor

* Theory "HOL.Rings": rule split_of_bool_asm is not split any longer,
analogously to split_if_asm. INCOMPATIBILITY.

* Theory "HOL.Bit_Operations": rule bit_0 is not default [simp] any

* Streamlined primitive definitions of division and modulus on integers.

* Theory "HOL.Fun":
  - Added predicate monotone_on and redefined monotone to be an
    abbreviation. Lemma monotone_def is explicitly provided for backward
    compatibility but its usage is discouraged. Minor INCOMPATIBILITY.
  - Changed argument order of mono_on and strict_mono_on to uniformize
    with monotone_on and the general "characterizing set at the beginning
    of predicates" preference. Also change them to be abbreviations
    of monotone_of. Lemmas mono_on_def and strict_mono_on_def are
    explicitly provided for backward compatibility but their usage is
    discouraged. INCOMPATIBILITY.
  - Move mono, strict_mono, antimono, and relevant lemmas to Fun theory.
    Also change them to be abbreviations of mono_on, strict_mono_on,
    and monotone, respectively. Lemmas mono_def, strict_mono_def, and
    antimono_def are explicitly provided for backward compatibility but
    their usage is discouraged. Minor INCOMPATIBILITY.
  - Added lemmas.

* Theory "HOL.Relation":
  - Added predicate reflp_on and redefined reflp to be an abbreviation.
    Lemma reflp_def is explicitly provided for backward compatibility
    but its usage is discouraged. Minor INCOMPATIBILITY.
  - Added predicate totalp_on and abbreviation totalp.
  - Replaced HOL.implies by Pure.imp in lemma reflp_mono for consistency
    with other lemmas. Minor INCOMPATIBILITY.
  - Added lemmas.

* Theory "HOL.Transitive_Closure":
  - Added lemmas.

* Theory "HOL-Library.Signed_Division": class signed_division carries
assumptions; use syntactic type classes signed_division and
signed_modulo as alternatives.

* New theory "HOL-Library.NList" of fixed length lists.

* New Theory "HOL-Library.Code_Abstract_Char" implements characters by
target language integers, sacrificing pattern patching in exchange for
dramatically increased performance for comparisons.

* Theory "HOL-Library.Char_ord": streamlined logical specifications.

* Theory "HOL-Library.Multiset":
  - Consolidated operation and fact names.
        multp ~> multp_code
        multeqp ~> multeqp_code
        multp_cancel_add_mset ~> multp_cancel_add_mset0
        multp_cancel_add_mset0[simplified] ~> multp_cancel_add_mset
        multp_code_iff ~> multp_code_iff_mult
        multeqp_code_iff ~> multeqp_code_iff_reflcl_mult
  - Moved mult1_lessE out of preorder type class and add explicit
    assumption. Minor INCOMPATIBILITY.
  - Added predicate multp equivalent to set mult. Reuse name previously
    used for what is now called multp_code. Minor INCOMPATIBILITY.
  - Lifted multiple lemmas from mult to multp.
  - Redefined less_multiset to be based on multp. INCOMPATIBILITY.
  - Added lemmas.

* Theory "HOL-Library.Sublist": added lemma map_mono_strict_suffix.

* Theory "HOL-ex.Sum_of_Powers" has been deleted. The same material is
in the AFP as Bernoulli.

* Session HOL-Algebra: some facts have been renamed to avoid fact name
clashes on interpretation:

    is_ring ~> ring_axioms
    cring ~> cring_axioms
    R_def ~> R_m_def


* Nitpick: To avoid technical issues, prefer non-JNI solvers to JNI
solvers by default. Minor INCOMPATIBILITY.

* Sledgehammer:
  - Redesigned multithreading to provide more fine grained prover
    schedules. The binary option 'slice' has been replaced by a numeric
    value 'slices' indicating the number of desired slices. Stronger
    provers can now be run by more than one thread simultaneously. The
    new option 'max_proofs' controls the number of proofs shown.
  - Introduced sledgehammer_outcome data type and changed return type of
    ML function Sledgehammer.run_sledgehammer from "bool * (string *
    string list)" to "bool * (sledgehammer_outcome * string)". The
    former value can be recomputed with "apsnd (ATP_Util.map_prod
    Sledgehammer.short_string_of_sledgehammer_outcome single)".
  - Added support for TX0 and TX1 TPTP formats and $ite/$let expressions
    in TH0 and TH1.
  - Added support for cvc5.
  - Generate Isar proofs by default when and only when the one-liner
    proof fails to replay and the Isar proof succeeds.
  - Replaced option "sledgehammer_atp_dest_dir" by
    "sledgehammer_atp_problem_dest_dir", for problem files, and
    "sledgehammer_atp_proof_dest_dir", for proof files. Minor
  - Removed support for experimental prover 'z3_tptp'.
  - The fastest successfully preplayed proof is always suggested.
  - All SMT solvers but Z3 now resort to suggest (smt (verit)) when no
    proof could be preplayed.
  - Added new "some_preplayed" value to "expect" option to specify that
    some successfully preplayed proof is expected. This is in contrast
    to the "some" value which doesn't specify whether preplay succeeds
    or not.

* Mirabelle:
  - Replaced sledgehammer option "keep" by "keep_probs", for problems
    files, and "keep_proofs" for proof files. Minor INCOMPATIBILITY.
  - Added option "-r INT" to randomize the goals with a given 64-bit
    seed before selection.
  - Added option "-y" for a dry run.
  - Renamed run_action to run in Mirabelle.action record. Minor
  - Run the actions on goals before commands "unfolding" and "using".

* (Co)datatype package:
  - BNFs now require a strict cardinality bound (<o instead of \<le>o).
    Minor INCOMPATIBILITY for existing manual BNF declarations.
  - Lemma map_ident_strong is now generated for all BNFs.

* More ambitious minimization of case expressions in generated code.

* Code generation for Scala: type annotations in pattern bindings are
printed in a way suitable for Scala 3.

*** ML ***

* Type Bytes.T supports scalable byte strings, beyond the limit of
String.maxSize (approx. 64 MB on 64_32 architecture).

* Operations for XZ compression (via Isabelle/Scala):

  XZ.compress: Bytes.T -> Bytes.T
  XZ.uncompress: Bytes.T -> Bytes.T

*** System ***

* Isabelle/Scala is now based on Scala 3. This is a completely different
compiler ("dotty") and a quite different source language (we are using
the classic Java-style syntax, not the new Python-style syntax).
Occasional INCOMPATIBILITY, see also the official Scala documentation

* External Isabelle tools implemented as .scala scripts are no longer
supported. INCOMPATIBILITY, instead provide a proper Isabelle/Scala
module with etc/build.props and "services" for a suitable class instance
of isabelle.Isabelle_Scala_Tools. For example, see
$ISABELLE_HOME/etc/build.props and its isabelle.Tools, which defines the
standard Isabelle tools.

* The session build database now maintains an additional "uuid" column
to identity the original build process uniquely. Thus other tools may
dependent symbolically on a particular build instance.

* Command-line tool "isabelle build_docker" supports Docker within Snap
more robustly; see also option -W.

* Command-line tool "isabelle scala_project" supports Gradle as
alternative to Maven: either option -G or -M needs to be specified
explicitly. This increases the chances that the Java/Scala IDE project
works properly.

* Command-line tool "isabelle hg_sync" synchronizes the working
directory of a local Mercurial repository with a target directory, using
rsync notation for destinations.

* Command-line tool "isabelle sync" synchronizes Isabelle + AFP
repositories with a target directory, based on "isabelle hg_sync". Local
jars and sessions images may be uploaded as well, to avoid redundant
builds on the remote side. This tool requires a Mercurial clone of the
Isabelle repository: a regular download of the distribution will not

* Command-line tool "isabelle log" has been refined to support multiple
sessions, and to match messages against regular expressions (using Java
Pattern syntax).

* System option "show_states" controls output of toplevel command states
(notably proof states) in batch-builds; in interactive mode this is
always done on demand. The option is relevant for tools that operate on
exported PIDE markup, e.g. document presentation or diagnostics. For

  isabelle build -o show_states FOL-ex
  isabelle log -v -U FOL-ex

Option "show_states" is also the default for the configuration option
"show_results" within the formal context.

Note that printing intermediate states may cause considerable slowdown
in building a session.

* Session ROOT entries support 'export_classpath' to augment the
Java/Scala name space for tools that allow dynamic loading of service
classes within a session context. A notable example is document
preparation, which works via the class isabelle.Document_Build.Engine
and is configured by the corresponding system option "document_build".
The Isabelle/Isar command 'scala_build_generated_files' helps to produce
a suitable .jar module for inclusion via 'export_classpath'.

* Isabelle/Scala SSH connections now use regular OpenSSH executables
from the local system: ssh, scp, sftp; the old ssh-java component has
been discontinued. This has various practical consequences:

  - Authentication and configuration works accurately via the official
    .ssh/known_hosts and .ssh/config files.

  - Host connections are usually shared (via multiplexed channels), to
    reduce the overhead for multiple commands. This also works for SSH
    connections for rsync (e.g. "isabelle sync"). Windows/Cygwin does
    not support multiplexing: the functionality should be the same, but
    slower, with a new connection for each command.

  - Multiple hops via "bastion hosts" can be easily configured in
    .ssh/config via ProxyJump declarations. The former Isabelle/Scala
    parameters for proxy_host etc. have been discontinued: minor

* The MLton compiler for x86_64-linux has been bundled as Isabelle
component, since Ubuntu 22.04 no longer provides a suitable package.
Note that on macOS, MLton is readily available via Homebrew:

The Isabelle settings refer to an executable "$ISABELLE_MLTON" and
command-line options $ISABELLE_MLTON_OPTIONS, which need to fit
together. Potential INCOMPATIBILITY for existing

* The system option "ML_system_apple" controls the use of native
Apple/ARM64 for Poly/ML: default "true". Like "ML_system_64" this only
works when saved in "$ISABELLE_HOME_USER/etc/preferences" (e.g. after
shutdown of Isabelle/jEdit).

* The headless PIDE session now supports adhoc editing of theories via
repeated "use_theories" on changed files. This functionality was
originally intended (e.g. see Isabelle2018), but it got lost due to
later improvements of "isabelle dump". Now it should work again, e.g. as
follows for "isabelle server &" and "isabelle client":

  session_start {"session": "HOL", "options": ["headless_consolidate_delay=0.5", "headless_prune_delay=5"]}
  use_theories {"session_id": "...", "theories": ["/home/makarius/tmp/Test"]}
  use_theories {"session_id": "...", "theories": ["/home/makarius/tmp/Test"]}
  purge_theories {"session_id":"...", "all": true}
  session_stop {"session_id": "..."}

New in Isabelle2021-1 (December 2021)

*** General ***

* The Isabelle/Haskell library ($ISABELLE_HOME/src/Tools/Haskell) has
been significantly improved. In particular, module Isabelle.Bytes
provides type Bytes for light-weight byte strings (with optional UTF8
interpretation), similar to type string in Isabelle/ML. Isabelle symbols
now work uniformly in Isabelle/Haskell vs. Isabelle/ML vs.

* Configuration option "show_results" controls output of final results
in commands like 'definition' or 'theorem'. Output is normally enabled
in interactive mode, but it could occasionally cause unnecessary
slowdown. It can be disabled like this:

  context notes [[show_results = false]]
    definition "test = True"
    theorem test by (simp add: test_def)

* Theory_Data / Generic_Data: "val extend = I" has been removed;
obsolete since Isabelle2021.

* More symbol definitions for the Z Notation (Isabelle fonts and LaTeX).
See also the group "Z Notation" in the Symbols dockable of

*** Isar ***

* Commands 'syntax' and 'no_syntax' now work in a local theory context,
but in contrast to 'notation' and 'no_notation' there is no proper way
to refer to local entities. Note that local syntax works well with
'bundle', e.g. see "lattice_syntax" vs. "no_lattice_syntax" in theory
Main of Isabelle/HOL.

* The improper proof command 'guess' is no longer part of by Pure, but
provided by the separate theory "Pure-ex.Guess". INCOMPATIBILITY,
existing applications need to import session "Pure-ex" and theory
"Pure-ex.Guess". Afterwards it is usually better eliminate the 'guess'
command, using explicit 'obtain' instead.

* More robust 'proof' outline for method "induct": support nested cases.

*** Isabelle/jEdit Prover IDE ***

* The main plugin for Isabelle/jEdit can be deactivated and reactivated
as documented --- was broken at least since Isabelle2018.

* Isabelle/jEdit is now composed more conventionally from the original
jEdit text editor in $JEDIT_HOME (with minor patches), plus two Isabelle
plugins that are produced in $JEDIT_SETTINGS/jars on demand. The main
isabelle.jedit module is now part of Isabelle/Scala (as one big

* Add-on components may provide their own jEdit plugins, via the new
Scala/Java module concept: instances of class
isabelle.Scala_Project.Plugin that are declared as "services" within
etc/build.props are activated on Isabelle/jEdit startup. E.g. see
existing isabelle.jedit.JEdit_Plugin0 (for isabelle_jedit_base.jar) and
isabelle.jedit.JEdit_Plugin1 (for isabelle_jedit_main.jar).

* Support for built-in font substitution of jEdit text area.

*** Document preparation ***

* HTML presentation now includes links to formal entities.

* High-quality blackboard-bold symbols from font "txmia" (LaTeX package
"pxfonts"): \<bbbA>\<bool>\<complex>\<bbbD>\<bbbE>\<bbbF>\<bbbG>\<bbbH>\<bbbI>\<bbbJ>\<bbbK>\<bbbL>\<bbbM>\<nat>\<bbbO>\<bbbP>\<rat>\<real>\<bbbS>\<bbbT>\<bbbU>\<bbbV>\<bbbW>\<bbbX>\<bbbY>\<int>.

* More predefined symbols: \<Parallel> \<interleave> \<sslash> (package "stmaryrd"), \<checkmark> \<crossmark> (LaTeX
package "pifont").

* Document antiquotations for ML text have been refined: "def" and "ref"
variants support index entries, e.g. @{ML} (no entry) vs. @{ML_def}
(bold entry) vs. @{ML_ref} (regular entry); @{ML_type} supports explicit
type arguments for constructors (only relevant for index), e.g.
@{ML_type \<open>'a list\<close>} vs. @{ML_type 'a \<open>list\<close>}; @{ML_op} has been renamed
to @{ML_infix}. Minor INCOMPATIBILITY concerning name and syntax.

* Option "document_logo" determines if an instance of the Isabelle logo
should be created in the document output directory. The given string
specifies the name of the logo variant, while "_" (underscore) refers to
the unnamed variant. The output file name is always "isabelle_logo.pdf".

* Option "document_build" determines the document build engine, as
defined in Isabelle/Scala (as system service). The subsequent engines
are provided by the Isabelle distribution:

  - "lualatex" (default): use ISABELLE_LUALATEX for a standard LaTeX
    build with optional ISABELLE_BIBTEX and ISABELLE_MAKEINDEX

  - "pdflatex": as above, but use ISABELLE_PDFLATEX (legacy mode for
    special LaTeX styles)

  - "build": delegate to the executable "./build pdf"

The presence of a "build" command within the document output directory
explicitly requires document_build=build. Minor INCOMPATIBILITY, need to
adjust session ROOT options.

* Option "document_comment_latex" enables regular LaTeX comment.sty,
instead of the historic version for plain TeX (default). The latter is
much faster, but in conflict with LaTeX classes like Dagstuhl LIPIcs.

* Option "document_echo" informs about document file names during
session presentation.

* Option "document_heading_prefix" specifies a prefix for the LaTeX
macro names generated from document heading commands like 'chapter',
'section' etc. The default is "isamarkup", so 'section' becomes
"\isamarkupsection" for example.

* The command-line tool "isabelle latex" has been discontinued,
INCOMPATIBILITY for old document build scripts.

  - Former "isabelle latex -o sty" has become obsolete: Isabelle .sty
    files are automatically generated within the document output

  - Former "isabelle latex -o pdf" should be replaced by
    "$ISABELLE_LUALATEX root" or "$ISABELLE_PDFLATEX root" (without
    quotes), according to the intended LaTeX engine.

  - Former "isabelle latex -o bbl" should be replaced by
    "$ISABELLE_BIBTEX root" (without quotes).

  - Former "isabelle latex -o idx" should be replaced by
    "$ISABELLE_MAKEINDEX root" (without quotes).

* Option "document_bibliography" explicitly enables the use of bibtex;
the default is to check the presence of root.bib, but it could have a
different name.

* Improved LaTeX typesetting of \<open>...\<close> using \guilsinglleft ...
\guilsinglright. INCOMPATIBILITY, need to use \usepackage[T1]{fontenc}
(which is now also the default in "isabelle mkroot").

* Simplified typesetting of \<guillemotleft>...\<guillemotright> using \guillemotleft ...
\guillemotright from \usepackage[T1]{fontenc} --- \usepackage{babel} is
no longer required.

*** Pure ***

* "global_interpretation" is applicable in instantiation and overloading
targets and in any nested target built on top of a target supporting

*** HOL ***

* New order prover.

* Theorems "antisym" and "eq_iff" in class "order" have been renamed to
"order.antisym" and "order.eq_iff", to coexist locally with "antisym"
and "eq_iff" from locale "ordering". INCOMPATIBILITY: significant
potential for change can be avoided if interpretations of type class
"order" are replaced or augmented by interpretations of locale

* Theorem "swap_def" now is always qualified as "Fun.swap_def". Minor
INCOMPATIBILITY; note that for most applications less elementary lemmas

* Lemma "permutes_induct" has been given stronger hypotheses and named

* Combinator "Fun.swap" resolved into a mere input abbreviation in
separate theory "Transposition" in HOL-Combinatorics. INCOMPATIBILITY.

* Theory Bit_Operations is now part of HOL-Main. Minor INCOMPATIBILITY.

* Infix syntax for bit operations AND, OR, XOR, NOT is now organized in
bundle bit_operations_syntax. INCOMPATIBILITY.

* Bit operations set_bit, unset_bit and flip_bit are now class

* Simplified class hierarchy for bit operations: bit operations reside
in classes (semi)ring_bit_operations, class semiring_bit_shifts is gone.

* Consecutive conversions to and from words are not collapsed in any
case: rules unsigned_of_nat, unsigned_of_int, signed_of_int,
signed_of_nat, word_of_nat_eq_0_iff, word_of_int_eq_0_iff are not simp
by default any longer.  INCOMPATIBILITY.

* Abbreviation "max_word" has been moved to session Word_Lib in the AFP,
as also have constants "shiftl1", "shiftr1", "sshiftr1", "bshiftr1",
"setBit", "clearBit". See there further the changelog in theory Guide.

* Reorganized classes and locales for boolean algebras. INCOMPATIBILITY.

* New simp rules: less_exp, min.absorb1, min.absorb2, min.absorb3,
min.absorb4, max.absorb1, max.absorb2, max.absorb3, max.absorb4. Minor

* The Mirabelle testing tool is now part of Main HOL, and accessible via
the command-line tool "isabelle mirabelle" (implemented in
Isabelle/Scala). It has become more robust and supports parallelism
within Isabelle/ML.

* Nitpick: External solver "MiniSat" is available for all supported
Isabelle platforms (including 64bit Windows and ARM); while
"MiniSat_JNI" only works for Intel Linux and macOS.

* Nitpick/Kodkod: default is back to external Java process (option
kodkod_scala = false), both for PIDE and batch builds. This reduces
confusion and increases robustness of timeouts, despite substantial
overhead to run an external JVM. For more fine-grained control, the
kodkod_scala option can be modified within the formal theory context
like this:

  declare [[kodkod_scala = false]]

* Sledgehammer:
  - Update of bundled provers:
      . E 2.6
      . Vampire 4.6 (with Open Source license)
      . veriT 2021.06.1-rmx
      . Zipperposition 2.1
      . Z3 4.4.1 for arm64-linux, which approximates Z3 4.4.0pre,
        but sometimes fails or crashes
  - Adjusted default provers:
      cvc4 vampire verit e spass z3 zipperposition
  - Adjusted Zipperposition's slicing.
  - Removed legacy "lam_lifting" (synonym for "lifting") from option
    "lam_trans". Minor INCOMPATIBILITY.
  - Renamed "hide_lams" to "opaque_lifting" in option "lam_trans". Minor
  - Added "opaque_combs" to option "lam_trans": lambda expressions are
    rewritten using combinators, but the combinators are kept opaque,
    i.e. without definitions.

* Metis:
  - Renamed option "hide_lams" to "opaque_lifting". Minor INCOMPATIBILITY.
  - Updated the Metis prover underlying the "metis" proof method to
    version 2.4 (release 20200713). The new version fixes one
    implementation defect. Very slight INCOMPATIBILITY.

* Theory HOL-Library.Lattice_Syntax has been superseded by bundle
"lattice_syntax": it can be used in a local context via 'include' or in
a global theory via 'unbundle'. The opposite declarations are bundled as
"no_lattice_syntax". Minor INCOMPATIBILITY.

* Theory "HOL-Library.Multiset": dedicated predicate "multiset" is gone,
use explict expression instead. Minor INCOMPATIBILITY.

* Theory "HOL-Library.Multiset": consolidated abbreviations Mempty,
Melem, not_Melem to empty_mset, member_mset, not_member_mset
respectively. Minor INCOMPATIBILITY.

* Theory "HOL-Library.Multiset": consolidated operation and fact names:
    inf_subset_mset ~> inter_mset
    sup_subset_mset ~> union_mset
    multiset_inter_def ~> inter_mset_def
    sup_subset_mset_def ~> union_mset_def
    multiset_inter_count ~> count_inter_mset
    sup_subset_mset_count ~> count_union_mset

* Theory "HOL-Library.Complex_Order": Defines less, less_eq on complex
numbers. Not imported by default.

* Theory "HOL-Library.Multiset": syntax precendence for membership
operations has been adjusted to match the corresponding precendences on

* Theory "HOL-Library.Cardinality": code generator setup based on the
type classes finite_UNIV and card_UNIV has been moved to
"HOL-Library.Code_Cardinality", to avoid incompatibilities with
other code setups for sets in AFP/Containers. Applications relying on
this code setup should import "HOL-Library.Code_Cardinality". Minor

* Theory "HOL-Library.Permutation" has been renamed to the more specific
"HOL-Library.List_Permutation". Note that most notions from that theory
are already present in theory "HOL-Combinatorics.Permutations".

* Dedicated session "HOL-Combinatorics". INCOMPATIBILITY: theories
"Permutations", "List_Permutation" (formerly "Permutation"), "Stirling",
"Multiset_Permutations", "Perm" have been moved there from session

* Theory "HOL-Combinatorics.Transposition" provides elementary swap
operation "transpose".

* Theory "HOL-Analysis.Infinite_Sum": new theory for infinite sums with
a more general definition than the existing theory Infinite_Set_Sum.
(Infinite_Set_Sum contains theorems relating the two definitions.)

* Theory "HOL-Analysis.Product_Vector": Instantiation of the product of
uniform spaces as a uniform space. Minor INCOMPATIBILITY: the old
definition "uniformity_prod_def" is available as a derived fact

* Session "HOL-Analysis" and "HOL-Probability": indexed products of
discrete distributions, negative binomial distribution, Hoeffding's
inequality, Chernoff bounds, Cauchy–Schwarz inequality for nn_integral,
and some more small lemmas. Some theorems that were stated awkwardly
before were corrected. Minor INCOMPATIBILITY.

* Session "HOL-Analysis": the complex Arg function has been identified
with the function "arg" of Complex_Main, renaming arg ~> Arg also in the
names of arg_bounded. Minor INCOMPATIBILITY.

* Session "HOL-Statespace": various improvements and cleanup.

*** ML ***

* External bash processes are always managed by Isabelle/Scala, in
contrast to Isabelle2021 where this was only done for macOS on Apple

The main Isabelle/ML interface is Isabelle_System.bash_process with
result type Process_Result.T (resembling class Process_Result in Scala);
derived operations Isabelle_System.bash and Isabelle_System.bash_output
provide similar functionality as before. The underlying TCP/IP server
within Isabelle/Scala is available to other programming languages as
well, notably Isabelle/Haskell.

Rare INCOMPATIBILITY due to subtle semantic differences:

  - Processes invoked from Isabelle/ML actually run in the context of
    the Java VM of Isabelle/Scala. The settings environment and current
    working directory are usually the same on both sides, but there can be
    subtle corner cases (e.g. unexpected uses of "cd" or "putenv" in ML).

  - Output via stdout and stderr is line-oriented: Unix vs. Windows
    line-endings are normalized towards Unix; presence or absence of a
    final newline is irrelevant. The original lines are available as
    Process_Result.out_lines/err_lines; the concatenated versions
    Process_Result.out/err *omit* a trailing newline (using
    Library.trim_line, which was occasional seen in applications before,
    but is no longer necessary).

  - Output needs to be plain text encoded in UTF-8: Isabelle/Scala
    recodes it temporarily as UTF-16. This works for well-formed Unicode
    text, but not for arbitrary byte strings. In such cases, the bash
    script should write tempory files, managed by Isabelle/ML operations
    like Isabelle_System.with_tmp_file to create a file name and to retrieve its content.

  - The Isabelle/Scala "bash_process" server requires a PIDE session
    context. This could be a regular batch session (e.g. "isabelle
    build"), a PIDE editor session (e.g. "isabelle jedit"), or headless
    PIDE (e.g. "isabelle dump" or "isabelle server"). Note that old
    "isabelle console" or raw "isabelle process" don't have that.

New Process_Result.timing works as in Isabelle/Scala, based on direct
measurements of the bash_process wrapper in C: elapsed time is always
available, CPU time is only available on Linux and macOS, GC time is

* The following Isabelle/ML system operations are run in the context of
Isabelle/Scala, within a PIDE session context:

  - Isabelle_System.make_directory
  - Isabelle_System.copy_dir
  - Isabelle_System.copy_file
  - Isabelle_System.copy_base_file
  - Isabelle_System.rm_tree

* Term operations under abstractions are now more robust (and more
strict) by using the formal proof context in subsequent operations:


This works under the assumption that terms are always properly declared
to the proof context (e.g. via Variable.declare_term). Failure to do so,
or working with the wrong context, will cause an error (exception Fail,
based on Term.USED_FREE from Term.dest_abs_fresh).

The Simplifier and equational conversions now use the above operations
routinely, and thus require user-space tools to be serious about the
proof context (notably in their use of Goal.prove, SUBPROOF etc.).
INCOMPATIBILITY in add-on tools is to be expected occasionally: a proper
context discipline needs to be followed.

* Former operations Term.dest_abs and Logic.dest_all (without a proper
context) have been discontinued. INCOMPATIBILITY, either use
Variable.dest_abs etc. above, or the following operations that imitate
the old behavior to a great extent:


This works under the assumption that the given (sub-)term directly shows
all free variables that need to be avoided when generating a fresh name.
A violation of the assumption are variables stemming from the enclosing
context that get involved in a proof only later.

* ML structures TFrees, TVars, Frees, Vars, Names provide scalable
operations to accumulate items from types and terms, using a fast
syntactic order. The original order of occurrences may be recovered as
well, e.g. via TFrees.list_set.

* Thm.instantiate, Thm.generalize and related operations (e.g.
Variable.import) now use scalable data structures from structure TVars,
Vars, Names etc. INCOMPATIBILITY: e.g. use TVars.empty and TVars.make
for immediate adoption; better use TVars.add, TVars.add_tfrees etc. for
scalable accumulation of items.

* Thm.instantiate_beta applies newly emerging abstractions to their
arguments in the term, but leaves other beta-redexes unchanged --- in
contrast to Drule.instantiate_normalize.

* ML antiquotation "instantiate" allows to instantiate formal entities
(types, terms, theorems) with values given ML. This works uniformly for
"typ", "term", "prop", "ctyp", "cterm", "cprop", "lemma" --- given as a
keyword after the instantiation.

A mode "(schematic)" behind the keyword means that some variables may
remain uninstantiated (fixed in the specification and schematic in the
result); by default, all variables need to be instantiated.

Newly emerging abstractions are applied to their arguments in the term
(using Thm.instantiate_beta).

Examples in HOL:

  fun make_assoc_type (A, B) =
    \<^instantiate>\<open>'a = A and 'b = B in typ \<open>('a \<times> 'b) list\<close>\<close>;

  val make_assoc_list =
    map (fn (x, y) =>
      \<^instantiate>\<open>'a = \<open>fastype_of x\<close> and 'b = \<open>fastype_of y\<close> and
        x and y in term \<open>(x, y)\<close> for x :: 'a and y :: 'b\<close>);

  fun symmetry x y =
    \<^instantiate>\<open>'a = \<open>Thm.ctyp_of_cterm x\<close> and x and y in
      lemma \<open>x = y \<Longrightarrow> y = x\<close> for x y :: 'a by simp\<close>

  fun symmetry_schematic A =
    \<^instantiate>\<open>'a = A in
      lemma (schematic) \<open>x = y \<Longrightarrow> y = x\<close> for x y :: 'a by simp\<close>

* ML antiquotation for embedded lemma supports local fixes, as usual in
many other Isar language elements. For example:

  @{lemma "x = x" for x :: nat by (rule refl)}

* ML antiquotations for type constructors and term constants:

    \<^Type>\<open>c T \<dots>\<close>       \<comment> \<open>same with type arguments\<close>
    \<^Type_fn>\<open>c T \<dots>\<close>    \<comment> \<open>fn abstraction, failure via exception TYPE\<close>
    \<^Const>\<open>c T \<dots>\<close>      \<comment> \<open>same with type arguments\<close>
    \<^Const>\<open>c for t \<dots>\<close>  \<comment> \<open>same with term arguments\<close>
    \<^Const_>\<open>c \<dots>\<close>       \<comment> \<open>same for patterns: case, let, fn\<close>
    \<^Const_fn>\<open>c T \<dots>\<close>   \<comment> \<open>fn abstraction, failure via exception TERM\<close>

The type/term arguments refer to nested ML source, which may contain
antiquotations recursively. The following argument syntax is supported:

  - an underscore (dummy pattern)
  - an atomic item of "embedded" syntax, e.g. identifier or cartouche
  - an antiquotation in control-symbol/cartouche form, e.g. \<^Type>\<open>c\<close>
    as short form of \<open>\<^Type>\<open>c\<close>\<close>.

Examples in HOL:

  val natT = \<^Type>\<open>nat\<close>;
  fun mk_funT (A, B) = \<^Type>\<open>fun A B\<close>;
  val dest_funT = \<^Type_fn>\<open>fun A B => \<open>(A, B)\<close>\<close>;
  fun mk_conj (A, B) = \<^Const>\<open>conj for A B\<close>;
  val dest_conj = \<^Const_fn>\<open>conj for A B => \<open>(A, B)\<close>\<close>;
  fun mk_eq T (t, u) = \<^Const>\<open>HOL.eq T for t u\<close>;
  val dest_eq = \<^Const_fn>\<open>HOL.eq T for t u => \<open>(T, (t, u))\<close>\<close>;

* ML antiquotations \<^make_judgment> and \<^dest_judgment> refer to
corresponding functions for the object-logic of the ML compilation
context. This supersedes older mk_Trueprop / dest_Trueprop operations.

* The "build" combinators of various data structures help to build
content from bottom-up, by applying an "add" function the "empty" value.
For example:

  - type 'a Symtab.table etc.: build
  - type 'a Names.table etc.: build
  - type 'a list: build and build_rev
  - type Buffer.T: build and build_content

For example, see src/Pure/PIDE/xml.ML:

  val content_of = Buffer.build_content o fold add_content;

* ML antiquotations \<^try>\<open>expr\<close> and \<^can>\<open>expr\<close> operate directly on
the given ML expression, in contrast to functions "try" and "can" that
modify application of a function.

* ML antiquotations for conditional ML text:


* ML profiling has been updated and reactivated, after some degration in

  - "isabelle build -o threads=1 -o profiling=..." works properly
    within the PIDE session context;

  - "isabelle profiling_report" now uses the session build database
    (like "isabelle log");

  - output uses non-intrusive tracing messages, instead of warnings.

*** System ***

* Almost complete support for arm64-linux platform. The reference
platform is Raspberry Pi 4 with 8 GB RAM running Pi OS (64 bit).

* Update to OpenJDK 17: the current long-term support version of Java.

* Update to Poly/ML 5.9 with improved support for ARM on Linux. On
macOS, the Intel version works more smoothly with Rosetta 2, as already
used in Isabelle2021. Further changes to Poly/ML are documented here:

* Perl is no longer required by Isabelle proper, and no longer provided
by specific Isabelle execution environments (Docker, Cygwin on Windows).
Minor INCOMPATIBILITY, add-on applications involving perl need to
provide it by different means. (Note that proper Isabelle systems
programming works via Scala/Java, without perl, python, ruby etc.).

* Each Isabelle component may specify a Scala/Java jar module
declaratively via etc/build.props (file names are relative to the
component directory). E.g. see $ISABELLE_HOME/etc/build.props with
further explanations in the "system" manual.

* Command-line tool "isabelle scala_build" allows to invoke the build
process of all Scala/Java modules explicitly. Normally this is done
implicitly on demand, e.g. for "isabelle scala" or "isabelle jedit".

* Command-line tool "isabelle scala_project" is has been improved in
various ways:
  - sources from all components with etc/build.props are included,
  - sources of for the jEdit text editor and the Isabelle/jEdit
    plugins (jedit_base and jedit_main) are included by default,
  - more sources may be given on the command-line,
  - options -f and -D make the tool more convenient,
  - Gradle has been replaced by Maven (less ambitious and more robust).

* Remote provers from SystemOnTPTP (notably for Sledgehammer) are now
managed via Isabelle/Scala instead of perl; the dependency on
libwww-perl has been eliminated (notably on Linux). Rare
INCOMPATIBILITY: HTTP proxy configuration now works via JVM properties

* System options may declare an implicit standard value, which is used
when the option is activated without providing an explicit value, e.g.
"isabelle build -o document -o document_output" instead of
"isabelle build -o document=true -o document_output=output". For options
of type "bool", the standard is always "true" and cannot be specified

* System option "document=true" is an alias for "document=pdf", and
"document=false" is an alias for "document=" (empty string).

* System option "system_log" specifies an optional log file for internal
messages produced by Output.system_message in Isabelle/ML; the standard
value "-" refers to console progress of the build job. This works for
"isabelle build" or any derivative of it.

* Command-line tool "isabelle version" supports repository archives
(without full .hg directory). It also provides more options.

* Obsolete settings variable ISABELLE_PLATFORM32 has been discontinued.
Note that only Windows supports old 32 bit executables, via settings
variable ISABELLE_WINDOWS_PLATFORM32. Everything else should be
(native Windows) or ISABELLE_APPLE_PLATFORM64 (Apple Silicon).

* Timeouts for Isabelle/ML tools are subject to system option
"timeout_scale", to support adjustments to slow machines. Before,
timeout_scale was only used for the overall session build process, now
it affects the underlying Timeout.apply in Isabelle/ML as well. It
treats a timeout specification 0 as "no timeout", instead of "immediate
timeout". Rare INCOMPATIBILITY in boundary cases.

New in Isabelle2021 (February 2021)

*** General ***

* On macOS, the directory layout now follows the other
platforms, without indirection via Contents/Resources/. INCOMPATIBILITY,
use e.g. instead of former or

* HTML presentation uses rich markup produced by Isabelle/PIDE,
resulting in more colors and links.

* HTML presentation includes auxiliary files (e.g. ML) for each theory.

* Proof method "subst" is confined to the original subgoal range: its
included distinct_subgoals_tac no longer affects unrelated subgoals.

* Theory_Data extend operation is obsolete and needs to be the identity
function; merge should be conservative and not reset to the empty value.
Subtle INCOMPATIBILITY and change of semantics (due to
Theory.join_theory from Isabelle2020). Special extend/merge behaviour at
the begin of a new theory can be achieved via Theory.at_begin.

*** Isabelle/jEdit Prover IDE ***

* Improved GUI look-and-feel: the portable and scalable "FlatLaf Light"
is used by default on all platforms (appearance similar to IntelliJ

* Improved markup for theory header imports: hyperlinks for theory files
work without formal checking of content.

* The prover process can download auxiliary files (e.g. 'ML_file') for
theories with remote URL. This requires the external "curl" program.

* Action "isabelle.goto-entity" (shortcut CS+d) jumps to the definition
of the formal entity at the caret position.

* The visual feedback on caret entity focus is normally restricted to
definitions within the visible text area. The keyboard modifier "CS"
overrides this: then all defining and referencing positions are shown.
See also option "jedit_focus_modifier".

* The jEdit status line includes widgets both for JVM and ML heap usage.
Ongoing ML ongoing garbage collection is shown as "ML cleanup".

* The Monitor dockable provides buttons to request a full garbage
collection and sharing of live data on the ML heap. It also includes
information about the Java Runtime system.

* PIDE support for session ROOTS: markup for directories.

* Update to jedit-5.6.0, the latest release. This version works properly
on macOS by default, without the special MacOSX plugin.

* Action "full-screen-mode" (shortcut F11 or S+F11) has been modified
for better approximate window size on macOS and Linux/X11.

* Improved GUI support for macOS 11.1 Big Sur: native fullscreen mode,
but non-native look-and-feel (FlatLaf).

* Hyperlinks to various file-formats (.pdf, .png, etc.) open an external
viewer, instead of re-using the jEdit text editor.

* IDE support for Naproche-SAD: Proof Checking of Natural Mathematical
Documents. See also $NAPROCHE_HOME/examples for files with .ftl or
.ftl.tex extension. The corresponding Naproche-SAD server process can be
disabled by setting the system option naproche_server=false and
restarting the Isabelle application.

*** Document preparation ***

* Keyword 'document_theories' within ROOT specifies theories from other
sessions that should be included in the generated document source
directory. This does not affect the generated session.tex: \input{...}
needs to be used separately.

* The standard LaTeX engine is now lualatex, according to settings
variable ISABELLE_PDFLATEX. This is mostly upwards compatible with old
pdflatex, but text encoding needs to conform strictly to utf8. Rare

* Discontinued obsolete DVI format and ISABELLE_LATEX settings variable:
document output is always PDF.

* Antiquotation @{tool} refers to Isabelle command-line tools, with
completion and formal reference to the source (external script or
internal Scala function).

* Antiquotation @{bash_function} refers to GNU bash functions that are
checked within the Isabelle settings environment.

* Antiquotations @{scala}, @{scala_object}, @{scala_type},
@{scala_method} refer to checked Isabelle/Scala entities.

*** Pure ***

* Session Pure-Examples contains notable examples for Isabelle/Pure
(former entries of HOL-Isar_Examples).

* Named contexts (locale and class specifications, locale and class
context blocks) allow bundle mixins for the surface context. This allows
syntax notations to be organized within bundles conveniently. See theory
"HOL-ex.Specifications_with_bundle_mixins" for examples and the isar-ref
manual for syntax descriptions.

* Definitions in locales produce rule which can be added as congruence
rule to protect foundational terms during simplification.

* Consolidated terminology and function signatures for nested targets:

  - Local_Theory.begin_nested replaces Local_Theory.open_target

  - Local_Theory.end_nested replaces Local_Theory.close_target

  - Combination of Local_Theory.begin_nested and
    Local_Theory.end_nested(_result) replaces


* Local_Theory.init replaces Generic_Target.init. Minor INCOMPATIBILITY.

*** HOL ***

* Session HOL-Examples contains notable examples for Isabelle/HOL
(former entries of HOL-Isar_Examples, HOL-ex etc.).

* An updated version of the veriT solver is now included as Isabelle
component. It can be used in the "smt" proof method via "smt (verit)" or
via "declare [[smt_solver = verit]]" in the context; see also session

* Zipperposition 2.0 is now included as Isabelle component for
experimentation, e.g. in "sledgehammer [prover = zipperposition]".

* Sledgehammer:
  - support veriT in proof preplay
  - take adventage of more cores in proof preplay

* Updated the Metis prover underlying the "metis" proof method to
version 2.4 (release 20180810). The new version fixes one soundness
defect and two incompleteness defects. Very slight INCOMPATIBILITY.

* Nitpick/Kodkod may be invoked directly within the running
Isabelle/Scala session (instead of an external Java process): this
improves reactivity and saves resources. This experimental feature is
guarded by system option "kodkod_scala" (default: true in PIDE
interaction, false in batch builds).

* Simproc "defined_all" and rewrite rule "subst_all" perform more
aggressive substitution with variables from assumptions.
INCOMPATIBILITY, consider repairing proofs locally like this:

  supply subst_all [simp del] [[simproc del: defined_all]]

* Simproc "datatype_no_proper_subterm" rewrites equalities "lhs = rhs"
on datatypes to "False" if either side is a proper subexpression of the
other (for any datatype with a reasonable size function).

* Syntax for state monad combinators fcomp and scomp is organized in
bundle state_combinator_syntax.  Minor INCOMPATIBILITY.

* Syntax for reflected term syntax is organized in bundle term_syntax,
discontinuing previous locale term_syntax.  Minor INCOMPATIBILITY.

* New constant "power_int" for exponentiation with integer exponent,
written as "x powi n".

* Added the "at most 1" quantifier, Uniq.

* For the natural numbers, "Sup {} = 0".

* New constant semiring_char gives the characteristic of any type of
class semiring_1, with the convenient notation CHAR('a). For example,
CHAR(nat) = CHAR(int) = CHAR(real) = 0, CHAR(17) = 17.

* HOL-Computational_Algebra.Polynomial: Definition and basic properties
of algebraic integers.

* Library theory "Bit_Operations" with generic bit operations.

* Library theory "Signed_Division" provides operations for signed
division, instantiated for type int.

* Theory "Multiset": removed misleading notation \<Union># for sum_mset;
replaced with \<Sum>\<^sub>#. Analogous notation for prod_mset also exists now.

* New theory "HOL-Library.Word" takes over material from former session
"HOL-Word". INCOMPATIBILITY: need to adjust imports.

* Theory "HOL-Library.Word": Type word is restricted to bit strings
consisting of at least one bit. INCOMPATIBILITY.

* Theory "HOL-Library.Word": Bit operations NOT, AND, OR, XOR are based
on generic algebraic bit operations from theory
"HOL-Library.Bit_Operations". INCOMPATIBILITY.

* Theory "HOL-Library.Word": Most operations on type word are set up for
transfer and lifting. INCOMPATIBILITY.

* Theory "HOL-Library.Word": Generic type conversions. INCOMPATIBILITY,
sometimes additional rewrite rules must be added to applications to get
a confluent system again.

* Theory "HOL-Library.Word": Uniform polymorphic "mask" operation for
both types int and word. INCOMPATIBILITY.

* Theory "HOL-Library.Word": Syntax for signed compare operators has
been consolidated with syntax of regular compare operators. Minor

* Former session "HOL-Word": Various operations dealing with bit values
represented as reversed lists of bools are separated into theory
Reversed_Bit_Lists in session Word_Lib in the AFP. INCOMPATIBILITY.

* Former session "HOL-Word": Theory "Word_Bitwise" has been moved to AFP
entry Word_Lib as theory "Bitwise". INCOMPATIBILITY.

* Former session "HOL-Word": Compound operation "bin_split" simplifies
by default into its components "drop_bit" and "take_bit".

* Former session "HOL-Word": Operations lsb, msb and set_bit are
separated into theories Least_significant_bit, Most_significant_bit and
Generic_set_bit respectively in session Word_Lib in the AFP.

* Former session "HOL-Word": Ancient int numeral representation has been
factored out in separate theory "Ancient_Numeral" in session Word_Lib in

* Former session "HOL-Word": Operations "bin_last", "bin_rest",
"bin_nth", "bintrunc", "sbintrunc", "norm_sint", "bin_cat" and
"max_word" are now mere input abbreviations. Minor INCOMPATIBILITY.

* Former session "HOL-Word": Misc ancient material has been factored out
into separate theories and moved to session Word_Lib in the AFP. See
theory "Guide" there for further information. INCOMPATIBILITY.

* Session HOL-TPTP: The "tptp_isabelle" and "tptp_sledgehammer" commands
are in working order again, as opposed to outputting "GaveUp" on nearly
all problems.

* Session "HOL-Hoare": concrete syntax only for Hoare triples, not
abstract language constructors.

* Session "HOL-Hoare": now provides a total correctness logic as well.

*** FOL ***

* Added the "at most 1" quantifier, Uniq, as in HOL.

* Simproc "defined_all" and rewrite rule "subst_all" have been changed
as in HOL.

*** ML ***

* Antiquotations @{scala_function}, @{scala}, @{scala_thread} refer to
registered Isabelle/Scala functions (of type String => String):
invocation works via the PIDE protocol.

* Path.append is available as overloaded "+" operator, similar to
corresponding Isabelle/Scala operation.

* ML statistics via an external Poly/ML process: this allows monitoring
the runtime system while the ML program sleeps.

*** System ***

* Isabelle server allows user-defined commands via

* Update/rebuild external provers on currently supported OS platforms,
notably CVC4 1.8, E prover 2.5, SPASS 3.8ds, CSDP 6.1.1.

* The command-line tool "isabelle log" prints prover messages from the
build database of the given session, following the the order of theory
sources, instead of erratic parallel evaluation. Consequently, the
session log file is restricted to system messages of the overall build
process, and thus becomes more informative.

* Discontinued obsolete isabelle display tool, and DVI_VIEWER settings

* The command-line tool "isabelle logo" only outputs PDF; obsolete EPS
(for DVI documents) has been discontinued. Former option -n has been
turned into -o with explicit file name. Minor INCOMPATIBILITY.

* The command-line tool "isabelle components" supports new options -u
and -x to manage $ISABELLE_HOME_USER/etc/components without manual
editing of Isabelle configuration files.

* The shell function "isabelle_directory" (within etc/settings of
components) augments the list of special directories for persistent
symbolic path names. This improves portability of heap images and
session databases. It used to be hard-wired for Isabelle + AFP, but
other projects may now participate on equal terms.

* The command-line tool "isabelle process" now prints output to
stdout/stderr separately and incrementally, instead of just one bulk to
stdout after termination. Potential INCOMPATIBILITY for external tools.

* The command-line tool "isabelle console" now supports interrupts
properly (on Linux and macOS).

* Batch-builds via "isabelle build" use a PIDE session with special
protocol: this allows to invoke Isabelle/Scala operations from
Isabelle/ML. Big build jobs (e.g. AFP) require extra heap space for the
java process, e.g. like this in $ISABELLE_HOME_USER/etc/settings:


This includes full PIDE markup, if option "build_pide_reports" is

* The command-line tool "isabelle build" provides option -P DIR to
produce PDF/HTML presentation in the specified directory; -P: refers to
the standard directory according to ISABELLE_BROWSER_INFO /
ISABELLE_BROWSER_INFO_SYSTEM settings. Generated PDF documents are taken
from the build database -- from this or earlier builds with option

* The command-line tool "isabelle document" generates theory documents
on the spot, using the underlying session build database (exported
LaTeX sources or existing PDF files). INCOMPATIBILITY, the former
"isabelle document" tool was rather different and has been discontinued.

* The command-line tool "isabelle sessions" explores the structure of
Isabelle sessions and prints result names in topological order (on

* The Isabelle/Scala "Progress" interface changed slightly and
"No_Progress" has been discontinued. INCOMPATIBILITY, use "new Progress"

* General support for Isabelle/Scala system services, configured via the
shell function "isabelle_scala_service" in etc/settings (e.g. of an
Isabelle component); see implementations of class
Isabelle_System.Service in Isabelle/Scala. This supersedes former
"isabelle_scala_tools" and "isabelle_file_format": minor

* The syntax of theory load commands (for auxiliary files) is now
specified in Isabelle/Scala, as instance of class
isabelle.Command_Span.Load_Command registered via isabelle_scala_service
in etc/settings. This allows more flexible schemes than just a list of
file extensions. Minor INCOMPATIBILITY, e.g. see theory
HOL-SPARK.SPARK_Setup to emulate the old behaviour.

* JVM system property "isabelle.laf" has been discontinued; the default
Swing look-and-feel is ""FlatLaf Light".

* Isabelle/Phabricator supports Ubuntu 20.04 LTS.

* Isabelle/Phabricator setup has been updated to follow ongoing
development: libphutil has been discontinued. Minor INCOMPATIBILITY:
existing server installations should remove libphutil from
/usr/local/bin/isabelle-phabricator-upgrade and each installation root
directory (e.g. /var/www/phabricator-vcs/libphutil).

* Experimental support for arm64-linux platform. The reference platform
is Raspberry Pi 4 with 8 GB RAM running Pi OS (64 bit).

* Support for Apple Silicon, using mostly x86_64-darwin runtime
translation via Rosetta 2 (e.g. Poly/ML and external provers), but also
some native arm64-darwin executables (e.g. Java).

New in Isabelle2020 (April 2020)

*** General ***

* Session ROOT files need to specify explicit 'directories' for import
of theory files. Directories cannot be shared by different sessions.
(Recall that import of theories from other sessions works via
session-qualified theory names, together with suitable 'sessions'
declarations in the ROOT.)

* Internal derivations record dependencies on oracles and other theorems
accurately, including the implicit type-class reasoning wrt. proven
class relations and type arities. In particular, the formal tagging with
"Pure.skip_proofs" of results stemming from "instance ... sorry" is now
propagated properly to theorems depending on such type instances.

* Command 'sorry' (oracle "Pure.skip_proofs") is more precise about the
actual proposition that is assumed in the goal and proof context. This
requires at least Proofterm.proofs = 1 to show up in theorem

* Command 'thm_oracles' prints all oracles used in given theorems,
covering the full graph of transitive dependencies.

* Command 'thm_deps' prints immediate theorem dependencies of the given
facts. The former graph visualization has been discontinued, because it
was hardly usable.

* Refined treatment of proof terms, including type-class proofs for
minor object-logics (FOL, FOLP, Sequents).

* The inference kernel is now confined to one main module: structure
Thm, without the former circular dependency on structure Axclass.

* Mixfix annotations may use "' " (single quote followed by space) to
separate delimiters (as documented in the isar-ref manual), without
requiring an auxiliary empty block. A literal single quote needs to be
escaped properly. Minor INCOMPATIBILITY.

*** Isar ***

* The proof method combinator (subproofs m) applies the method
expression m consecutively to each subgoal, constructing individual
subproofs internally. This impacts the internal construction of proof
terms: it makes a cascade of let-expressions within the derivation tree
and may thus improve scalability.

* Attribute "trace_locales" activates tracing of locale instances during
roundup. It replaces the diagnostic command 'print_dependencies', which
has been discontinued.

*** Isabelle/jEdit Prover IDE ***

* Prover IDE startup is now much faster, because theory dependencies are
no longer explored in advance. The overall session structure with its
declarations of 'directories' is sufficient to locate theory files. Thus
the "session focus" of option "isabelle jedit -S" has become obsolete
(likewise for "isabelle vscode_server -S"). Existing option "-R" is both
sufficient and more convenient to start editing a particular session.

* Actions isabelle.tooltip (CS+b) and isabelle.message (CS+m) display
tooltip message popups, corresponding to mouse hovering with/without the
CONTROL/COMMAND key pressed.

* The following actions allow to navigate errors within the current
document snapshot:

  isabelle.first-error (CS+a)
  isabelle.last-error (CS+z) (CS+n)
  isabelle.prev-error (CS+p)

* Support more brackets: \<llangle> \<rrangle> (intended for implicit argument syntax).

* Action isabelle.jconsole (menu item Plugins / Isabelle / Java/VM
Monitor) applies the jconsole tool on the running Isabelle/jEdit
process. This allows to monitor resource usage etc.

* More adequate default font sizes for Linux on HD / UHD displays:
automatic font scaling is usually absent on Linux, in contrast to
Windows and macOS.

* The default value for the jEdit property "view.antiAlias" (menu item
Utilities / Global Options / Text Area / Anti Aliased smooth text) is
now "subpixel HRGB", instead of former "standard". Especially on Linux
this often leads to faster text rendering, but can also cause problems
with odd color shades. An alternative is to switch back to "standard"
here, and set the following Java system property:

    isabelle jedit -Dsun.java2d.opengl=true

This can be made persistent via JEDIT_JAVA_OPTIONS in
$ISABELLE_HOME_USER/etc/settings. For the "Isabelle2020" desktop
application there is a corresponding options file in the same directory.

*** Isabelle/VSCode Prover IDE ***

* Update of State and Preview panels to use new WebviewPanel API of

*** HOL ***

* Improvements of the 'lift_bnf' command:
  - Add support for quotient types.
  - Generate transfer rules for the lifted map/set/rel/pred constants
    (theorems "<type>.<constant>_transfer_raw").

* Term_XML.Encode/Decode.term uses compact representation of Const
"typargs" from the given declaration environment. This also makes more
sense for translations to lambda-calculi with explicit polymorphism.
INCOMPATIBILITY, use Term_XML.Encode/Decode.term_raw in special

* ASCII membership syntax concerning big operators for infimum and
supremum has been discontinued. INCOMPATIBILITY.

* Removed multiplicativity assumption from class
"normalization_semidom". Introduced various new intermediate classes
with the multiplicativity assumption; many theorem statements
(especially involving GCD/LCM) had to be adapted. This allows for a more
natural instantiation of the algebraic typeclasses for e.g. Gaussian

* Clear distinction between types for bits (False / True) and Z2 (0 /
1): theory HOL-Library.Bit has been renamed accordingly.

* Dynamic facts "algebra_split_simps" and "field_split_simps" correspond
to algebra_simps and field_simps but contain more aggressive rules
potentially splitting goals; algebra_split_simps roughly replaces
sign_simps and field_split_simps can be used instead of divide_simps.

* Theory HOL.Complete_Lattices:
renamed Inf_Sup -> Inf_eq_Sup and Sup_Inf -> Sup_eq_Inf

* Theory HOL-Library.Monad_Syntax: infix operation "bind" (\<bind>)
associates to the left now as is customary.

* Theory HOL-Library.Ramsey: full finite Ramsey's theorem with
multiple colours and arbitrary exponents.

* Session HOL-Proofs: build faster thanks to better treatment of proof
terms in Isabelle/Pure.

* Session HOL-Word: bitwise NOT-operator has proper prefix syntax. Minor

* Session HOL-Analysis: proof method "metric" implements a decision
procedure for simple linear statements in metric spaces.

* Session HOL-Complex_Analysis has been split off from HOL-Analysis.

*** ML ***

* Theory construction may be forked internally, the operation
Theory.join_theory recovers a single result theory. See also the example
in theory "HOL-ex.Join_Theory".

* Antiquotation @{oracle_name} inlines a formally checked oracle name.

* Minimal support for a soft-type system within the Isabelle logical
framework (module Soft_Type_System).

* Former Variable.auto_fixes has been replaced by slightly more general
Proof_Context.augment: it is subject to an optional soft-type system of
the underlying object-logic. Minor INCOMPATIBILITY.

* More scalable Export.export using XML.tree to avoid premature string
allocations, with convenient shortcut XML.blob. Minor INCOMPATIBILITY.

* Prover IDE support for the underlying Poly/ML compiler (not the basis
library). Open $ML_SOURCES/ROOT.ML in Isabelle/jEdit to browse the
implementation with full markup.

*** System ***

* Standard rendering for more Isabelle symbols: \<llangle> \<rrangle> \<bbar> \<sqdot>

* The command-line tool "isabelle scala_project" creates a Gradle
project configuration for Isabelle/Scala/jEdit, to support Scala IDEs
such as IntelliJ IDEA.

* The command-line tool "isabelle phabricator_setup" facilitates
self-hosting of the Phabricator software-development platform, with
support for Git, Mercurial, Subversion repositories. This helps to avoid
monoculture and to escape the gravity of centralized version control by
Github and/or Bitbucket. For further documentation, see chapter
"Phabricator server administration" in the "system" manual. A notable
example installation is

* The command-line tool "isabelle hg_setup" simplifies the setup of
Mercurial repositories, with hosting via Phabricator or SSH file server

* The command-line tool "isabelle imports" has been discontinued: strict
checking of session directories enforces session-qualified theory names
in applications -- users are responsible to specify session ROOT entries

* The command-line tool "isabelle dump" and its underlying
Isabelle/Scala module isabelle.Dump has become more scalable, by
splitting sessions and supporting a base logic image. Minor
INCOMPATIBILITY in options and parameters.

* The command-line tool "isabelle build_docker" has been slightly
improved: it is now properly documented in the "system" manual.

* Isabelle/Scala support for the Linux platform (Ubuntu): packages,
users, system services.

* Isabelle/Scala support for proof terms (with full type/term
information) in module isabelle.Term.

* Isabelle/Scala: more scalable output of YXML files, e.g. relevant for
"isabelle dump".

* Theory export via Isabelle/Scala has been reworked. The former "fact"
name space is now split into individual "thm" items: names are
potentially indexed, such as "foo" for singleton facts, or "bar(1)",
"bar(2)", "bar(3)" for multi-facts. Theorem dependencies are now
exported as well: this spans an overall dependency graph of internal
inferences; it might help to reconstruct the formal structure of theory
libraries. See also the module isabelle.Export_Theory in Isabelle/Scala.

* Theory export of structured specifications, based on internal
declarations of Spec_Rules by packages like 'definition', 'inductive',
'primrec', 'function'.

have been discontinued -- deprecated since Isabelle2018.

* More complete x86_64 platform support on macOS, notably Catalina where
old x86 has been discontinued.

* Update to GHC stack 2.1.3 with stackage lts-13.19/ghc-8.6.4.

* Update to OCaml Opam 2.0.6 (using ocaml 4.05.0 as before).

New in Isabelle2019 (June 2019)

*** General ***

* The font collection "Isabelle DejaVu" is systematically derived from
the existing "DejaVu" fonts, with variants "Sans Mono", "Sans", "Serif"
and styles "Normal", "Bold", "Italic/Oblique", "Bold-Italic/Oblique".
The DejaVu base fonts are retricted to well-defined Unicode ranges and
augmented by special Isabelle symbols, taken from the former
"IsabelleText" font (which is no longer provided separately). The line
metrics and overall rendering quality is closer to original DejaVu.
INCOMPATIBILITY with display configuration expecting the old
"IsabelleText" font: use e.g. "Isabelle DejaVu Sans Mono" instead.

* The Isabelle fonts render "\<inverse>" properly as superscript "-1".

* Old-style inner comments (* ... *) within the term language are no
longer supported (legacy feature in Isabelle2018).

* Old-style {* verbatim *} tokens are explicitly marked as legacy
feature and will be removed soon. Use \<open>cartouche\<close> syntax instead, e.g.
via "isabelle update_cartouches -t" (available since Isabelle2015).

* Infix operators that begin or end with a "*" are now parenthesized
without additional spaces, e.g. "(*)" instead of "( * )". Minor

* Mixfix annotations may use cartouches instead of old-style double
quotes, e.g. (infixl \<open>+\<close> 60). The command-line tool "isabelle update -u
mixfix_cartouches" allows to update existing theory sources

* ML setup commands (e.g. 'setup', 'method_setup', 'parse_translation')
need to provide a closed expression -- without trailing semicolon. Minor

* Commands 'generate_file', 'export_generated_files', and
'compile_generated_files' support a stateless (PIDE-conformant) model
for generated sources and compiled binaries of other languages. The
compilation process is managed in Isabelle/ML, and results exported to
the session database for further use (e.g. with "isabelle export" or
"isabelle build -e").

*** Isabelle/jEdit Prover IDE ***

* Fonts for the text area, gutter, GUI elements etc. use the "Isabelle
DejaVu" collection by default, which provides uniform rendering quality
with the usual Isabelle symbols. Line spacing no longer needs to be
adjusted: properties for the old IsabelleText font had "Global Options /
Text Area / Extra vertical line spacing (in pixels): -2", it now
defaults to 1, but 0 works as well.

* The jEdit File Browser is more prominent in the default GUI layout of
Isabelle/jEdit: various virtual file-systems provide access to Isabelle
resources, notably via "favorites:" (or "Edit Favorites").

* Further markup and rendering for "plain text" (e.g. informal prose)
and "raw text" (e.g. verbatim sources). This improves the visual
appearance of formal comments inside the term language, or in general
for repeated alternation of formal and informal text.

* Action "isabelle-export-browser" points the File Browser to the theory
exports of the current buffer, based on the "isabelle-export:" virtual
file-system. The directory view needs to be reloaded manually to follow
ongoing document processing.

* Action "isabelle-session-browser" points the File Browser to session
information, based on the "isabelle-session:" virtual file-system. Its
entries are structured according to chapter / session names, the open
operation is redirected to the session ROOT file.

* Support for user-defined file-formats via class isabelle.File_Format
in Isabelle/Scala (e.g. see isabelle.Bibtex.File_Format), configured via
the shell function "isabelle_file_format" in etc/settings (e.g. of an
Isabelle component).

* System option "jedit_text_overview" allows to disable the text
overview column.

* Command-line options "-s" and "-u" of "isabelle jedit" override the
default for system option "system_heaps" that determines the heap
storage directory for "isabelle build". Option "-n" is now clearly
separated from option "-s".

* The Isabelle/jEdit desktop application uses the same options as
"isabelle jedit" for its internal "isabelle build" process: the implicit
option "-o system_heaps" (or "-s") has been discontinued. This reduces
the potential for surprise wrt. command-line tools.

* The official download of the Isabelle/jEdit application already
contains heap images for Isabelle/HOL within its main directory: thus
the first encounter becomes faster and more robust (e.g. when run from a
read-only directory).

* Isabelle DejaVu fonts are available with hinting by default, which is
relevant for low-resolution displays. This may be disabled via system
option "isabelle_fonts_hinted = false" in
$ISABELLE_HOME_USER/etc/preferences -- it occasionally yields better

* OpenJDK 11 has quite different font rendering, with better glyph
shapes and improved sub-pixel anti-aliasing. In some situations results
might be *worse* than Oracle Java 8, though -- a proper HiDPI / UHD
display is recommended.

* OpenJDK 11 supports GTK version 2.2 and 3 (according to system
property jdk.gtk.version). The factory default is version 3, but
ISABELLE_JAVA_SYSTEM_OPTIONS includes "-Djdk.gtk.version=2.2" to make
this more conservative (as in Java 8). Depending on the GTK theme
configuration, "-Djdk.gtk.version=3" might work better or worse.

*** Document preparation ***

* Document markers are formal comments of the form \<^marker>\<open>marker_body\<close> that
are stripped from document output: the effect is to modify the semantic
presentation context or to emit markup to the PIDE document. Some
predefined markers are taken from the Dublin Core Metadata Initiative,
e.g. \<^marker>\<open>contributor arg\<close> or \<^marker>\<open>license arg\<close> and produce PIDE markup that
can be retrieved from the document database.

* Old-style command tags %name are re-interpreted as markers with
proof-scope \<^marker>\<open>tag (proof) name\<close> and produce LaTeX environments as
before. Potential INCOMPATIBILITY: multiple markers are composed in
canonical order, resulting in a reversed list of tags in the
presentation context.

* Marker \<^marker>\<open>tag name\<close> does not apply to the proof of a top-level goal
statement by default (e.g. 'theorem', 'lemma'). This is a subtle change
of semantics wrt. old-style %name.

* In Isabelle/jEdit, the string "\tag" may be completed to a "\<^marker>\<open>tag \<close>"

* Document antiquotation option "cartouche" indicates if the output
should be delimited as cartouche; this takes precedence over the
analogous option "quotes".

* Many document antiquotations are internally categorized as "embedded"
and expect one cartouche argument, which is typically used with the
\<^control>\<open>cartouche\<close> notation (e.g. \<^term>\<open>\<lambda>x y. x\<close>). The cartouche
delimiters are stripped in output of the source (antiquotation option
"source"), but it is possible to enforce delimiters via option
"source_cartouche", e.g. @{term [source_cartouche] \<open>\<lambda>x y. x\<close>}.

*** Isar ***

* Implicit cases goal1, goal2, goal3, etc. have been discontinued
(legacy feature since Isabelle2016).

* More robust treatment of structural errors: begin/end blocks take
precedence over goal/proof. This is particularly relevant for the
headless PIDE session and server.

* Command keywords of kind thy_decl / thy_goal may be more specifically
fit into the traditional document model of "definition-statement-proof"
via thy_defn / thy_stmt / thy_goal_defn / thy_goal_stmt.

*** HOL ***

* Command 'export_code' produces output as logical files within the
theory context, as well as formal session exports that can be
materialized via command-line tools "isabelle export" or "isabelle build
-e" (with 'export_files' in the session ROOT). Isabelle/jEdit also
provides a virtual file-system "isabelle-export:" that can be explored
in the regular file-browser. A 'file_prefix' argument allows to specify
an explicit name prefix for the target file (SML, OCaml, Scala) or
directory (Haskell); the default is "export" with a consecutive number
within each theory.

* Command 'export_code': the 'file' argument is now legacy and will be
removed soon: writing to the physical file-system is not well-defined in
a reactive/parallel application like Isabelle. The empty 'file' argument
has been discontinued already: it is superseded by the file-browser in
Isabelle/jEdit on "isabelle-export:". Minor INCOMPATIBILITY.

* Command 'code_reflect' no longer supports the 'file' argument: it has
been superseded by 'file_prefix' for stateless file management as in
'export_code'. Minor INCOMPATIBILITY.

* Code generation for OCaml: proper strings are used for literals.

* Code generation for OCaml: Zarith supersedes Nums as library for
proper integer arithmetic. The library is located via standard
invocations of "ocamlfind" (via ISABELLE_OCAMLFIND settings variable).
The environment provided by "isabelle ocaml_setup" already contains this
tool and the required packages. Minor INCOMPATIBILITY.

* Code generation for Haskell: code includes for Haskell must contain
proper module frame, nothing is added magically any longer.

* Code generation: slightly more conventional syntax for 'code_stmts'
antiquotation. Minor INCOMPATIBILITY.

* Theory List: the precedence of the list_update operator has changed:
"f a [n := x]" now needs to be written "(f a)[n := x]".

* The functions \<Union>, \<Inter>, \<Squnion>, \<Sqinter> (not the corresponding binding operators)
now have the same precedence as any other prefix function symbol. Minor

* Simplified syntax setup for big operators under image. In rare
situations, type conversions are not inserted implicitly any longer
and need to be given explicitly. Auxiliary abbreviations INFIMUM,
SUPREMUM, UNION, INTER should now rarely occur in output and are just
retained as migration auxiliary. Abbreviations MINIMUM and MAXIMUM

* The simplifier uses image_cong_simp as a congruence rule. The historic
and not really well-formed congruence rules INF_cong*, SUP_cong*, are
not used by default any longer. INCOMPATIBILITY; consider using declare
image_cong_simp [cong del] in extreme situations.

* INF_image and SUP_image are no default simp rules any longer.
INCOMPATIBILITY, prefer image_comp as simp rule if needed.

* Strong congruence rules (with =simp=> in the premises) for constant f
are now uniformly called f_cong_simp, in accordance with congruence
rules produced for mappers by the datatype package. INCOMPATIBILITY.

* Retired lemma card_Union_image; use the simpler card_UN_disjoint

* Facts sum_mset.commute and prod_mset.commute have been renamed to
sum_mset.swap and prod_mset.swap, similarly to sum.swap and prod.swap.

* ML structure Inductive: slightly more conventional naming schema.

* ML: Various _global variants of specification tools have been removed.
Minor INCOMPATIBILITY, prefer combinators
Named_Target.theory_map[_result] to lift specifications to the global
theory level.

* Theory HOL-Library.Simps_Case_Conv: 'case_of_simps' now supports
overlapping and non-exhaustive patterns and handles arbitrarily nested
patterns. It uses on the same algorithm as HOL-Library.Code_Lazy, which
assumes sequential left-to-right pattern matching. The generated
equation no longer tuples the arguments on the right-hand side.

* Theory HOL-Library.Multiset: the \<Union># operator now has the same
precedence as any other prefix function symbol.

* Theory HOL-Library.Cardinal_Notations has been discontinued in favor
of the bundle cardinal_syntax (available in theory Main). Minor

* Session HOL-Library and HOL-Number_Theory: Exponentiation by squaring,
used for computing powers in class "monoid_mult" and modular

* Session HOL-Computational_Algebra: Formal Laurent series and overhaul
of Formal power series.

* Session HOL-Number_Theory: More material on residue rings in
Carmichael's function, primitive roots, more properties for "ord".

* Session HOL-Analysis: Better organization and much more material
at the level of abstract topological spaces.

* Session HOL-Algebra: Free abelian groups, etc., ported from HOL Light;
 algebraic closure of a field by de Vilhena and Baillon.

* Session HOL-Homology has been added. It is a port of HOL Light's
homology library, with new proofs of "invariance of domain" and related

* Session HOL-SPARK: .prv files are no longer written to the
file-system, but exported to the session database. Results may be
retrieved via "isabelle build -e HOL-SPARK-Examples" on the

* Sledgehammer:
  - The URL for SystemOnTPTP, which is used by remote provers, has been
  - The machine-learning-based filter MaSh has been optimized to take
    less time (in most cases).

* SMT: reconstruction is now possible using the SMT solver veriT.

* Session HOL-Word:
  * New theory More_Word as comprehensive entrance point.
  * Merged type class bitss into type class bits.

*** ML ***

* Command 'generate_file' allows to produce sources for other languages,
with antiquotations in the Isabelle context (only the control-cartouche
form). The default "cartouche" antiquotation evaluates an ML expression
of type string and inlines the result as a string literal of the target
language. For example, this works for Haskell as follows:

  generate_file "Pure.hs" = \<open>
  module Isabelle.Pure where
    allConst, impConst, eqConst :: String
    allConst = \<open>\<^const_name>\<open>Pure.all\<close>\<close>
    impConst = \<open>\<^const_name>\<open>Pure.imp\<close>\<close>
    eqConst = \<open>\<^const_name>\<open>Pure.eq\<close>\<close>

See also commands 'export_generated_files' and 'compile_generated_files'
to use the results.

* ML evaluation (notably via command 'ML' or 'ML_file') is subject to
option ML_environment to select a named environment, such as "Isabelle"
for Isabelle/ML, or "SML" for official Standard ML.

* ML antiquotation @{master_dir} refers to the master directory of the
underlying theory, i.e. the directory of the theory file.

* ML antiquotation @{verbatim} inlines its argument as string literal,
preserving newlines literally. The short form \<^verbatim>\<open>abc\<close> is particularly

* Local_Theory.reset is no longer available in user space. Regular
definitional packages should use balanced blocks of
Local_Theory.open_target versus Local_Theory.close_target instead, or
the Local_Theory.subtarget(_result) combinator. Rare INCOMPATIBILITY.

* Original PolyML.pointerEq is retained as a convenience for tools that
don't use Isabelle/ML (where this is called "pointer_eq").

*** System ***

* Update to OpenJDK 11: the current long-term support version of Java.

* Update to Poly/ML 5.8 allows to use the native x86_64 platform without
the full overhead of 64-bit values everywhere. This special x86_64_32
mode provides up to 16GB ML heap, while program code and stacks are
allocated elsewhere. Thus approx. 5 times more memory is available for
applications compared to old x86 mode (which is no longer used by
Isabelle). The switch to the x86_64 CPU architecture also avoids
compatibility problems with Linux and macOS, where 32-bit applications
are gradually phased out.

* System option "checkpoint" has been discontinued: obsolete thanks to
improved memory management in Poly/ML.

* System option "system_heaps" determines where to store the session
image of "isabelle build" (and other tools using that internally).
Former option "-s" is superseded by option "-o system_heaps".
INCOMPATIBILITY in command-line syntax.

* Session directory $ISABELLE_HOME/src/Tools/Haskell provides some
source modules for Isabelle tools implemented in Haskell, notably for

* The command-line tool "isabelle build -e" retrieves theory exports
from the session build database, using 'export_files' in session ROOT

* The command-line tool "isabelle update" uses Isabelle/PIDE in
batch-mode to update theory sources based on semantic markup produced in
Isabelle/ML. Actual updates depend on system options that may be enabled
via "-u OPT" (for "update_OPT"), see also $ISABELLE_HOME/etc/options
section "Theory update". Theory sessions are specified as in "isabelle

* The command-line tool "isabelle update -u control_cartouches" changes
antiquotations into control-symbol format (where possible): @{NAME}
becomes \<^NAME> and @{NAME ARG} becomes \<^NAME>\<open>ARG\<close>.

* Support for Isabelle command-line tools defined in Isabelle/Scala.
Instances of class Isabelle_Scala_Tools may be configured via the shell
function "isabelle_scala_tools" in etc/settings (e.g. of an Isabelle

* Isabelle Server command "use_theories" supports "nodes_status_delay"
for continuous output of node status information. The time interval is
specified in seconds; a negative value means it is disabled (default).

* Isabelle Server command "use_theories" terminates more robustly in the
presence of structurally broken sources: full consolidation of theories
is no longer required.

* OCaml tools and libraries are now accesed via ISABELLE_OCAMLFIND,
which needs to point to a suitable version of "ocamlfind" (e.g. via
OPAM, see below). INCOMPATIBILITY: settings variables ISABELLE_OCAML and
ISABELLE_OCAMLC are no longer supported.

* Support for managed installations of Glasgow Haskell Compiler and
OCaml via the following command-line tools:

  isabelle ghc_setup
  isabelle ghc_stack

  isabelle ocaml_setup
  isabelle ocaml_opam

The global installation state is determined by the following settings
(and corresponding directory contents):



After setup, the following Isabelle settings are automatically
redirected (overriding existing user settings):



The old meaning of these settings as locally installed executables may
be recovered by purging the directories ISABELLE_STACK_ROOT /
ISABELLE_OPAM_ROOT, or by resetting these variables in

New in Isabelle2018 (August 2018)

*** General ***

* Session-qualified theory names are mandatory: it is no longer possible
to refer to unqualified theories from the parent session.
INCOMPATIBILITY for old developments that have not been updated to
Isabelle2017 yet (using the "isabelle imports" tool).

* Only the most fundamental theory names are global, usually the entry
points to major logic sessions: Pure, Main, Complex_Main, HOLCF, IFOL,
FOL, ZF, ZFC etc. INCOMPATIBILITY, need to use qualified names for
formerly global "HOL-Probability.Probability" and "HOL-SPARK.SPARK".

* Global facts need to be closed: no free variables and no hypotheses.

* Facts stemming from locale interpretation are subject to lazy
evaluation for improved performance. Rare INCOMPATIBILITY: errors
stemming from interpretation morphisms might be deferred and thus
difficult to locate; enable system option "strict_facts" temporarily to
avoid this.

* Marginal comments need to be written exclusively in the new-style form
"\<comment> \<open>text\<close>", old ASCII variants like "-- {* ... *}" are no longer
supported. INCOMPATIBILITY, use the command-line tool "isabelle
update_comments" to update existing theory files.

* Old-style inner comments (* ... *) within the term language are legacy
and will be discontinued soon: use formal comments "\<comment> \<open>...\<close>" or "\<^cancel>\<open>...\<close>"

* The "op <infix-op>" syntax for infix operators has been replaced by
"(<infix-op>)". If <infix-op> begins or ends with a "*", there needs to
be a space between the "*" and the corresponding parenthesis.
INCOMPATIBILITY, use the command-line tool "isabelle update_op" to
convert theory and ML files to the new syntax. Because it is based on
regular expression matching, the result may need a bit of manual
postprocessing. Invoking "isabelle update_op" converts all files in the
current directory (recursively). In case you want to exclude conversion
of ML files (because the tool frequently also converts ML's "op"
syntax), use option "-m".

* Theory header 'abbrevs' specifications need to be separated by 'and'.

* Command 'external_file' declares the formal dependency on the given
file name, such that the Isabelle build process knows about it, but
without specific Prover IDE management.

* Session ROOT entries no longer allow specification of 'files'. Rare
INCOMPATIBILITY, use command 'external_file' within a proper theory

* Session root directories may be specified multiple times: each
accessible ROOT file is processed only once. This facilitates
specification of $ISABELLE_HOME_USER/ROOTS or command-line options like
-d or -D for "isabelle build" and "isabelle jedit". Example:

  isabelle build -D '~~/src/ZF'

* The command 'display_drafts' has been discontinued. INCOMPATIBILITY,
use action "isabelle.draft" (or "print") in Isabelle/jEdit instead.

* In HTML output, the Isabelle symbol "\<hyphen>" is rendered as explicit
Unicode hyphen U+2010, to avoid unclear meaning of the old "soft hyphen"
U+00AD. Rare INCOMPATIBILITY, e.g. copy-paste of historic Isabelle HTML

*** Isabelle/jEdit Prover IDE ***

* The command-line tool "isabelle jedit" provides more flexible options
for session management:

  - option -R builds an auxiliary logic image with all theories from
    other sessions that are not already present in its parent

  - option -S is like -R, with a focus on the selected session and its
    descendants (this reduces startup time for big projects like AFP)

  - option -A specifies an alternative ancestor session for options -R
    and -S

  - option -i includes additional sessions into the name-space of

    isabelle jedit -R HOL-Number_Theory
    isabelle jedit -R HOL-Number_Theory -A HOL
    isabelle jedit -d '$AFP' -S Formal_SSA -A HOL
    isabelle jedit -d '$AFP' -S Formal_SSA -A HOL-Analysis
    isabelle jedit -d '$AFP' -S Formal_SSA -A HOL-Analysis -i CryptHOL

* PIDE markup for session ROOT files: allows to complete session names,
follow links to theories and document files etc.

* Completion supports theory header imports, using theory base name.
E.g. "Prob" may be completed to "HOL-Probability.Probability".

* Named control symbols (without special Unicode rendering) are shown as
bold-italic keyword. This is particularly useful for the short form of
antiquotations with control symbol: \<^name>\<open>argument\<close>. The action
"isabelle.antiquoted_cartouche" turns an antiquotation with 0 or 1
arguments into this format.

* Completion provides templates for named symbols with arguments,
e.g. "\<comment> \<open>ARGUMENT\<close>" or "\<^emph>\<open>ARGUMENT\<close>".

* Slightly more parallel checking, notably for high priority print
functions (e.g. State output).

* The view title is set dynamically, according to the Isabelle
distribution and the logic session name. The user can override this via
set-view-title (stored persistently in $JEDIT_SETTINGS/perspective.xml).

* System options "spell_checker_include" and "spell_checker_exclude"
supersede former "spell_checker_elements" to determine regions of text
that are subject to spell-checking. Minor INCOMPATIBILITY.

* Action "isabelle.preview" is able to present more file formats,
notably bibtex database files and ML files.

* Action "isabelle.draft" is similar to "isabelle.preview", but shows a
plain-text document draft. Both are available via the menu "Plugins /

* When loading text files, the Isabelle symbols encoding UTF-8-Isabelle
is only used if there is no conflict with existing Unicode sequences in
the file. Otherwise, the fallback encoding is plain UTF-8 and Isabelle
symbols remain in literal \<symbol> form. This avoids accidental loss of
Unicode content when saving the file.

* Bibtex database files (.bib) are semantically checked.

* Update to jedit-5.5.0, the latest release.

*** Isabelle/VSCode Prover IDE ***

* HTML preview of theories and other file-formats similar to

* Command-line tool "isabelle vscode_server" accepts the same options
-A, -R, -S, -i for session selection as "isabelle jedit". This is
relevant for isabelle.args configuration settings in VSCode. The former
option -A (explore all known session files) has been discontinued: it is
enabled by default, unless option -S is used to focus on a particular
spot in the session structure. INCOMPATIBILITY.

*** Document preparation ***

* Formal comments work uniformly in outer syntax, inner syntax (term
language), Isabelle/ML and some other embedded languages of Isabelle.
See also "Document comments" in the isar-ref manual. The following forms
are supported:

  - marginal text comment: \<comment> \<open>\<dots>\<close>
  - canceled source: \<^cancel>\<open>\<dots>\<close>
  - raw LaTeX: \<^latex>\<open>\<dots>\<close>

* Outside of the inner theory body, the default presentation context is
theory Pure. Thus elementary antiquotations may be used in markup
commands (e.g. 'chapter', 'section', 'text') and formal comments.

* System option "document_tags" specifies alternative command tags. This
is occasionally useful to control the global visibility of commands via
session options (e.g. in ROOT).

* Document markup commands ('section', 'text' etc.) are implicitly
tagged as "document" and visible by default. This avoids the application
of option "document_tags" to these commands.

* Isabelle names are mangled into LaTeX macro names to allow the full
identifier syntax with underscore, prime, digits. This is relevant for
antiquotations in control symbol notation, e.g. \<^const_name> becomes

* Document preparation with skip_proofs option now preserves the content
more accurately: only terminal proof steps ('by' etc.) are skipped.

* Document antiquotation @{theory name} requires the long
session-qualified theory name: this is what users reading the text
normally need to import.

* Document antiquotation @{session name} checks and prints the given
session name verbatim.

* Document antiquotation @{cite} now checks the given Bibtex entries
against the Bibtex database files -- only in batch-mode session builds.

* Command-line tool "isabelle document" has been re-implemented in
Isabelle/Scala, with simplified arguments and explicit errors from the
latex and bibtex process. Minor INCOMPATIBILITY.

* Session ROOT entry: empty 'document_files' means there is no document
for this session. There is no need to specify options [document = false]

*** Isar ***

* Command 'interpret' no longer exposes resulting theorems as literal
facts, notably for the \<open>prop\<close> notation or the "fact" proof method. This
improves modularity of proofs and scalability of locale interpretation.
Rare INCOMPATIBILITY, need to refer to explicitly named facts instead
(e.g. use 'find_theorems' or 'try' to figure this out).

* The old 'def' command has been discontinued (legacy since
Isbelle2016-1). INCOMPATIBILITY, use 'define' instead -- usually with
object-logic equality or equivalence.

*** Pure ***

* The inner syntax category "sort" now includes notation "_" for the
dummy sort: it is effectively ignored in type-inference.

* Rewrites clauses (keyword 'rewrites') were moved into the locale
expression syntax, where they are part of locale instances. In
interpretation commands rewrites clauses now need to occur before 'for'
and 'defines'. Rare INCOMPATIBILITY; definitions immediately subject to
rewriting may need to be pulled up into the surrounding theory.

* For 'rewrites' clauses, if activating a locale instance fails, fall
back to reading the clause first. This helps avoid qualification of
locale instances where the qualifier's sole purpose is avoiding
duplicate constant declarations.

* Proof method "simp" now supports a new modifier "flip:" followed by a
list of theorems. Each of these theorems is removed from the simpset
(without warning if it is not there) and the symmetric version of the
theorem (i.e. lhs and rhs exchanged) is added to the simpset. For "auto"
and friends the modifier is "simp flip:".

*** HOL ***

* Sledgehammer: bundled version of "vampire" (for non-commercial users)
helps to avoid fragility of "remote_vampire" service.

* Clarified relationship of characters, strings and code generation:

  - Type "char" is now a proper datatype of 8-bit values.

  - Conversions "nat_of_char" and "char_of_nat" are gone; use more
    general conversions "of_char" and "char_of" with suitable type
    constraints instead.

  - The zero character is just written "CHR 0x00", not "0" any longer.

  - Type "String.literal" (for code generation) is now isomorphic to
    lists of 7-bit (ASCII) values; concrete values can be written as
    "STR ''...''" for sequences of printable characters and "STR 0x..."
    for one single ASCII code point given as hexadecimal numeral.

  - Type "String.literal" supports concatenation "... + ..." for all
    standard target languages.

  - Theory HOL-Library.Code_Char is gone; study the explanations
    concerning "String.literal" in the tutorial on code generation to
    get an idea how target-language string literals can be converted to
    HOL string values and vice versa.

  - Session Imperative-HOL: operation "raise" directly takes a value of
    type "String.literal" as argument, not type "string".


* Code generation: Code generation takes an explicit option
"case_insensitive" to accomodate case-insensitive file systems.

* Abstract bit operations as part of Main: push_bit, take_bit, drop_bit.

* New, more general, axiomatization of complete_distrib_lattice. The
former axioms:

  "sup x (Inf X) = Inf (sup x ` X)" and "inf x (Sup X) = Sup (inf x ` X)"

are replaced by:

  "Inf (Sup ` A) <= Sup (Inf ` {f ` A | f . (! Y \<in> A . f Y \<in> Y)})"

The instantiations of sets and functions as complete_distrib_lattice are
moved to Hilbert_Choice.thy because their proofs need the Hilbert choice
operator. The dual of this property is also proved in theory

* New syntax for the minimum/maximum of a function over a finite set:
MIN x\<in>A. B and even MIN x. B (only useful for finite types), also MAX.

* Clarifed theorem names:

  Min.antimono ~> Min.subset_imp
  Max.antimono ~> Max.subset_imp


* SMT module:

  - The 'smt_oracle' option is now necessary when using the 'smt' method
    with a solver other than Z3. INCOMPATIBILITY.

  - The encoding to first-order logic is now more complete in the
    presence of higher-order quantifiers. An 'smt_explicit_application'
    option has been added to control this. INCOMPATIBILITY.

* Facts sum.commute(_restrict) and prod.commute(_restrict) renamed to
sum.swap(_restrict) and prod.swap(_restrict), to avoid name clashes on
interpretation of abstract locales. INCOMPATIBILITY.

* Predicate coprime is now a real definition, not a mere abbreviation.

* Predicate pairwise_coprime abolished, use "pairwise coprime" instead.

* The relator rel_filter on filters has been strengthened to its
canonical categorical definition with better properties.

* Generalized linear algebra involving linear, span, dependent, dim
from type class real_vector to locales module and vector_space.

  span_inc ~> span_superset
  span_superset ~> span_base
  span_eq ~> span_eq_iff


* Class linordered_semiring_1 covers zero_less_one also, ruling out
pathologic instances. Minor INCOMPATIBILITY.

* Theory HOL.List: functions "sorted_wrt" and "sorted" now compare every
element in a list to all following elements, not just the next one.

* Theory HOL.List syntax:

  - filter-syntax "[x <- xs. P]" is no longer output syntax, but only
    input syntax

  - list comprehension syntax now supports tuple patterns in "pat <- xs"

* Theory Map: "empty" must now be qualified as "Map.empty".

* Removed nat-int transfer machinery. Rare INCOMPATIBILITY.

* Fact mod_mult_self4 (on nat) renamed to Suc_mod_mult_self3, to avoid
clash with fact mod_mult_self4 (on more generic semirings).

* Eliminated some theorem aliasses:
  even_times_iff ~> even_mult_iff
  mod_2_not_eq_zero_eq_one_nat ~> not_mod_2_eq_0_eq_1
  even_of_nat ~> even_int_iff


* Eliminated some theorem duplicate variations:

  - dvd_eq_mod_eq_0_numeral can be replaced by dvd_eq_mod_eq_0
  - mod_Suc_eq_Suc_mod can be replaced by mod_Suc
  - mod_Suc_eq_Suc_mod [symmetrict] can be replaced by mod_simps
  - mod_eq_0_iff can be replaced by mod_eq_0_iff_dvd and dvd_def
  - the witness of mod_eqD can be given directly as "_ div _"


* Classical setup: Assumption "m mod d = 0" (for m d :: nat) is no
longer aggresively destroyed to "\<exists>q. m = d * q". INCOMPATIBILITY, adding
"elim!: dvd" to classical proof methods in most situations restores
broken proofs.

* Theory HOL-Library.Conditional_Parametricity provides command
'parametric_constant' for proving parametricity of non-recursive
definitions. For constants that are not fully parametric the command
will infer conditions on relations (e.g., bi_unique, bi_total, or type
class conditions such as "respects 0") sufficient for parametricity. See
theory HOL-ex.Conditional_Parametricity_Examples for some examples.

* Theory HOL-Library.Code_Lazy provides a new preprocessor for the code
generator to generate code for algebraic types with lazy evaluation
semantics even in call-by-value target languages. See the theories
HOL-ex.Code_Lazy_Demo and HOL-Codegenerator_Test.Code_Lazy_Test for some

* Theory HOL-Library.Landau_Symbols has been moved here from AFP.

* Theory HOL-Library.Old_Datatype no longer provides the legacy command
'old_datatype'. INCOMPATIBILITY.

* Theory HOL-Computational_Algebra.Polynomial_Factorial does not provide
instances of rat, real, complex as factorial rings etc. Import
HOL-Computational_Algebra.Field_as_Ring explicitly in case of need.

* Session HOL-Algebra: renamed (^) to [^] to avoid conflict with new
infix/prefix notation.

* Session HOL-Algebra: revamped with much new material. The set of
isomorphisms between two groups is now denoted iso rather than iso_set.

* Session HOL-Analysis: the Arg function now respects the same interval
as Ln, namely (-pi,pi]; the old Arg function has been renamed Arg2pi.

* Session HOL-Analysis: the functions zorder, zer_poly, porder and
pol_poly have been redefined. All related lemmas have been reworked.

* Session HOL-Analysis: infinite products, Moebius functions, the
Riemann mapping theorem, the Vitali covering theorem,
change-of-variables results for integration and measures.

* Session HOL-Real_Asymp: proof method "real_asymp" proves asymptotics
or real-valued functions (limits, "Big-O", etc.) automatically.
See also ~~/src/HOL/Real_Asymp/Manual for some documentation.

* Session HOL-Types_To_Sets: more tool support (unoverload_type combines
internalize_sorts and unoverload) and larger experimental application
(type based linear algebra transferred to linear algebra on subspaces).

*** ML ***

* Operation Export.export emits theory exports (arbitrary blobs), which
are stored persistently in the session build database.

* Command 'ML_export' exports ML toplevel bindings to the global
bootstrap environment of the ML process. This allows ML evaluation
without a formal theory context, e.g. in command-line tools like
"isabelle process".

*** System ***

* Mac OS X 10.10 Yosemite is now the baseline version; Mavericks is no
longer supported.

* Linux and Windows/Cygwin is for x86_64 only, old 32bit platform
support has been discontinued.

* Java runtime is for x86_64 only. Corresponding Isabelle settings have
instead of former 32/64 variants. INCOMPATIBILITY.

phased out due to unclear preference of 32bit vs. 64bit architecture.
Explicit GNU bash expressions are now preferred, for example (with

  #Posix executables (Unix or Cygwin), with preference for 64bit

  #native Windows or Unix executables, with preference for 64bit

  #native Windows (32bit) or Unix executables (preference for 64bit)

* Command-line tool "isabelle build" supports new options:
  - option -B NAME: include session NAME and all descendants
  - option -S: only observe changes of sources, not heap images
  - option -f: forces a fresh build

* Command-line tool "isabelle build" options -c -x -B refer to
descendants wrt. the session parent or import graph. Subtle
INCOMPATIBILITY: options -c -x used to refer to the session parent graph

* Command-line tool "isabelle build" takes "condition" options with the
corresponding environment values into account, when determining the
up-to-date status of a session.

* The command-line tool "dump" dumps information from the cumulative
PIDE session database: many sessions may be loaded into a given logic
image, results from all loaded theories are written to the output

* Command-line tool "isabelle imports -I" also reports actual session
imports. This helps to minimize the session dependency graph.

* The command-line tool "export" and 'export_files' in session ROOT
entries retrieve theory exports from the session build database.

* The command-line tools "isabelle server" and "isabelle client" provide
access to the Isabelle Server: it supports responsive session management
and concurrent use of theories, based on Isabelle/PIDE infrastructure.
See also the "system" manual.

* The command-line tool "isabelle update_comments" normalizes formal
comments in outer syntax as follows: \<comment> \<open>text\<close> (whith a single space to
approximate the appearance in document output). This is more specific
than former "isabelle update_cartouches -c": the latter tool option has
been discontinued.

* The command-line tool "isabelle mkroot" now always produces a document
outline: its options have been adapted accordingly. INCOMPATIBILITY.

* The command-line tool "isabelle mkroot -I" initializes a Mercurial
repository for the generated session files.

mode") determine the directory locations of the main build artefacts --
instead of hard-wired directories in ISABELLE_HOME_USER (or

* Settings ISABELLE_PATH and ISABELLE_OUTPUT have been discontinued:
heap images and session databases are always stored in
$ISABELLE_HEAPS/$ML_IDENTIFIER (command-line default) or
$ISABELLE_HEAPS_SYSTEM/$ML_IDENTIFIER (main Isabelle application or
"isabelle jedit -s" or "isabelle build -s").

* ISABELLE_LATEX and ISABELLE_PDFLATEX now include platform-specific
options for improved error reporting. Potential INCOMPATIBILITY with
unusual LaTeX installations, may have to adapt these settings.

* Update to Poly/ML 5.7.1 with slightly improved performance and PIDE
markup for identifier bindings. It now uses The GNU Multiple Precision
Arithmetic Library (libgmp) on all platforms, notably Mac OS X with
32/64 bit.

New in Isabelle2017 (October 2017)

*** General ***

* Experimental support for Visual Studio Code (VSCode) as alternative
Isabelle/PIDE front-end, see also

VSCode is a new type of application that continues the concepts of
"programmer's editor" and "integrated development environment" towards
fully semantic editing and debugging -- in a relatively light-weight
manner. Thus it fits nicely on top of the Isabelle/PIDE infrastructure.
Technically, VSCode is based on the Electron application framework
(Node.js + Chromium browser + V8), which is implemented in JavaScript
and TypeScript, while Isabelle/VSCode mainly consists of Isabelle/Scala
modules around a Language Server implementation.

* Theory names are qualified by the session name that they belong to.
This affects imports, but not the theory name space prefix (which is
just the theory base name as before).

In order to import theories from other sessions, the ROOT file format
provides a new 'sessions' keyword. In contrast, a theory that is
imported in the old-fashioned manner via an explicit file-system path
belongs to the current session, and might cause theory name conflicts
later on. Theories that are imported from other sessions are excluded
from the current session document. The command-line tool "isabelle
imports" helps to update theory imports.

* The main theory entry points for some non-HOL sessions have changed,
to avoid confusion with the global name "Main" of the session HOL. This
leads to the follow renamings:

  CTT/Main.thy    ~>  CTT/CTT.thy
  ZF/Main.thy     ~>  ZF/ZF.thy
  ZF/Main_ZF.thy  ~>  ZF/ZF.thy
  ZF/Main_ZFC.thy ~>  ZF/ZFC.thy
  ZF/ZF.thy       ~>  ZF/ZF_Base.thy


* Commands 'alias' and 'type_alias' introduce aliases for constants and
type constructors, respectively. This allows adhoc changes to name-space
accesses within global or local theory contexts, e.g. within a 'bundle'.

* Document antiquotations @{prf} and @{full_prf} output proof terms
(again) in the same way as commands 'prf' and 'full_prf'.

* Computations generated by the code generator can be embedded directly
into ML, alongside with @{code} antiquotations, using the following

  @{computation ... terms: ... datatypes: ...} :
    ((term -> term) -> 'ml option -> 'a) -> Proof.context -> term -> 'a
  @{computation_conv ... terms: ... datatypes: ...} :
    (Proof.context -> 'ml -> conv) -> Proof.context -> conv
  @{computation_check terms: ... datatypes: ...} : Proof.context -> conv

See src/HOL/ex/Computations.thy,
src/HOL/Decision_Procs/Commutative_Ring.thy and
src/HOL/Decision_Procs/Reflective_Field.thy for examples and the
tutorial on code generation.

*** Prover IDE -- Isabelle/Scala/jEdit ***

* Session-qualified theory imports allow the Prover IDE to process
arbitrary theory hierarchies independently of the underlying logic
session image (e.g. option "isabelle jedit -l"), but the directory
structure needs to be known in advance (e.g. option "isabelle jedit -d"
or a line in the file $ISABELLE_HOME_USER/ROOTS).

* The PIDE document model maintains file content independently of the
status of jEdit editor buffers. Reloading jEdit buffers no longer causes
changes of formal document content. Theory dependencies are always
resolved internally, without the need for corresponding editor buffers.
The system option "jedit_auto_load" has been discontinued: it is
effectively always enabled.

* The Theories dockable provides a "Purge" button, in order to restrict
the document model to theories that are required for open editor

* The Theories dockable indicates the overall status of checking of each
entry. When all forked tasks of a theory are finished, the border is
painted with thick lines; remaining errors in this situation are
represented by a different border color.

* Automatic indentation is more careful to avoid redundant spaces in
intermediate situations. Keywords are indented after input (via typed
characters or completion); see also option "jedit_indent_input".

* Action "isabelle.preview" opens an HTML preview of the current theory
document in the default web browser.

* Command-line invocation "isabelle jedit -R -l LOGIC" opens the ROOT
entry of the specified logic session in the editor, while its parent is
used for formal checking.

* The main Isabelle/jEdit plugin may be restarted manually (using the
jEdit Plugin Manager), as long as the "Isabelle Base" plugin remains
enabled at all times.

* Update to current jedit-5.4.0.

*** Pure ***

* Deleting the last code equations for a particular function using
[code del] results in function with no equations (runtime abort) rather
than an unimplemented function (generation time abort). Use explicit
[[code drop:]] to enforce the latter. Minor INCOMPATIBILITY.

* Proper concept of code declarations in code.ML:
  - Regular code declarations act only on the global theory level, being
    ignored with warnings if syntactically malformed.
  - Explicitly global code declarations yield errors if syntactically
  - Default code declarations are silently ignored if syntactically

* Clarified and standardized internal data bookkeeping of code
declarations: history of serials allows to track potentially
non-monotonous declarations appropriately. Minor INCOMPATIBILITY.

*** HOL ***

* The Nunchaku model finder is now part of "Main".

* SMT module:
  - A new option, 'smt_nat_as_int', has been added to translate 'nat' to
    'int' and benefit from the SMT solver's theory reasoning. It is
    disabled by default.
  - The legacy module "src/HOL/Library/Old_SMT.thy" has been removed.
  - Several small issues have been rectified in the 'smt' command.

* (Co)datatype package: The 'size_gen_o_map' lemma is no longer
generated for datatypes with type class annotations. As a result, the
tactic that derives it no longer fails on nested datatypes. Slight

* Command and antiquotation "value" with modified default strategy:
terms without free variables are always evaluated using plain evaluation
only, with no fallback on normalization by evaluation. Minor

* Theories "GCD" and "Binomial" are already included in "Main" (instead
of "Complex_Main").

* Constant "surj" is a full input/output abbreviation (again).

* Dropped aliasses RangeP, DomainP for Rangep, Domainp respectively.

* Renamed ii to imaginary_unit in order to free up ii as a variable
name. The syntax \<i> remains available. INCOMPATIBILITY.

* Dropped abbreviations transP, antisymP, single_valuedP; use constants
transp, antisymp, single_valuedp instead. INCOMPATIBILITY.

* Constant "subseq" in Topological_Spaces has been removed -- it is
subsumed by "strict_mono". Some basic lemmas specific to "subseq" have
been renamed accordingly, e.g. "subseq_o" -> "strict_mono_o" etc.

* Theory List: "sublist" renamed to "nths" in analogy with "nth", and
"sublisteq" renamed to "subseq". Minor INCOMPATIBILITY.

* Theory List: new generic function "sorted_wrt".

* Named theorems mod_simps covers various congruence rules concerning
mod, replacing former zmod_simps. INCOMPATIBILITY.

* Swapped orientation of congruence rules mod_add_left_eq,
mod_add_right_eq, mod_add_eq, mod_mult_left_eq, mod_mult_right_eq,
mod_mult_eq, mod_minus_eq, mod_diff_left_eq, mod_diff_right_eq,

* Generalized some facts:
    zminus_zmod ~> mod_minus_eq
    zdiff_zmod_left ~> mod_diff_left_eq
    zdiff_zmod_right ~> mod_diff_right_eq
    zmod_eq_dvd_iff ~> mod_eq_dvd_iff

* Algebraic type class hierarchy of euclidean (semi)rings in HOL:
euclidean_(semi)ring, euclidean_(semi)ring_cancel,
unique_euclidean_(semi)ring; instantiation requires provision of a
euclidean size.

* Theory "HOL-Number_Theory.Euclidean_Algorithm" has been reworked:
  - Euclidean induction is available as rule eucl_induct.
  - Constants Euclidean_Algorithm.gcd, Euclidean_Algorithm.lcm,
    Euclidean_Algorithm.Gcd and Euclidean_Algorithm.Lcm allow
    easy instantiation of euclidean (semi)rings as GCD (semi)rings.
  - Coefficients obtained by extended euclidean algorithm are
    available as "bezout_coefficients".

* Theory "Number_Theory.Totient" introduces basic notions about Euler's
totient function previously hidden as solitary example in theory
Residues. Definition changed so that "totient 1 = 1" in agreement with
the literature. Minor INCOMPATIBILITY.

* New styles in theory "HOL-Library.LaTeXsugar":
  - "dummy_pats" for printing equations with "_" on the lhs;
  - "eta_expand" for printing eta-expanded terms.

* Theory "HOL-Library.Permutations": theorem bij_swap_ompose_bij has
been renamed to bij_swap_compose_bij. INCOMPATIBILITY.

* New theory "HOL-Library.Going_To_Filter" providing the "f going_to F"
filter for describing points x such that f(x) is in the filter F.

* Theory "HOL-Library.Formal_Power_Series": constants X/E/L/F have been
renamed to fps_X/fps_exp/fps_ln/fps_hypergeo to avoid polluting the name

* Theory "HOL-Library.FinFun" has been moved to AFP (again).

* Theory "HOL-Library.FuncSet": some old and rarely used ASCII
replacement syntax has been removed. INCOMPATIBILITY, standard syntax
with symbols should be used instead. The subsequent commands help to
reproduce the old forms, e.g. to simplify porting old theories:

syntax (ASCII)
  "_PiE" :: "pttrn \<Rightarrow> 'a set \<Rightarrow> 'b set \<Rightarrow> ('a \<Rightarrow> 'b) set"  ("(3PIE _:_./ _)" 10)
  "_Pi"  :: "pttrn \<Rightarrow> 'a set \<Rightarrow> 'b set \<Rightarrow> ('a \<Rightarrow> 'b) set"  ("(3PI _:_./ _)" 10)
  "_lam" :: "pttrn \<Rightarrow> 'a set \<Rightarrow> 'a \<Rightarrow> 'b \<Rightarrow> ('a \<Rightarrow> 'b)"  ("(3%_:_./ _)" [0,0,3] 3)

* Theory "HOL-Library.Multiset": the simprocs on subsets operators of
multisets have been renamed:

  msetless_cancel_numerals ~> msetsubset_cancel
  msetle_cancel_numerals ~> msetsubset_eq_cancel


* Theory "HOL-Library.Pattern_Aliases" provides input and output syntax
for pattern aliases as known from Haskell, Scala and ML.

* Theory "HOL-Library.Uprod" formalizes the type of unordered pairs.

* Session HOL-Analysis: more material involving arcs, paths, covering
spaces, innessential maps, retracts, infinite products, simplicial
complexes. Baire Category theorem. Major results include the Jordan
Curve Theorem and the Great Picard Theorem.

* Session HOL-Algebra has been extended by additional lattice theory:
the Knaster-Tarski fixed point theorem and Galois Connections.

* Sessions HOL-Computational_Algebra and HOL-Number_Theory: new notions
of squarefreeness, n-th powers, and prime powers.

* Session "HOL-Computional_Algebra" covers many previously scattered
theories, notably Euclidean_Algorithm, Factorial_Ring,
Formal_Power_Series, Fraction_Field, Fundamental_Theorem_Algebra,
Normalized_Fraction, Polynomial_FPS, Polynomial, Primes. Minor

*** System ***

* Isabelle/Scala: the SQL module supports access to relational
databases, either as plain file (SQLite) or full-scale server
(PostgreSQL via local port or remote ssh connection).

* Results of "isabelle build" are recorded as SQLite database (i.e.
"Application File Format" in the sense of This allows systematic
access via operations from module Sessions.Store in Isabelle/Scala.

* System option "parallel_proofs" is 1 by default (instead of more
aggressive 2). This requires less heap space and avoids burning parallel
CPU cycles, while full subproof parallelization is enabled for repeated
builds (according to parallel_subproofs_threshold).

* System option "record_proofs" allows to change the global
Proofterm.proofs variable for a session. Regular values are are 0, 1, 2;
a negative value means the current state in the ML heap image remains

* Isabelle settings variable ISABELLE_SCALA_BUILD_OPTIONS has been

* Isabelle settings variables ISABELLE_WINDOWS_PLATFORM,
native Windows platform (independently of the Cygwin installation). This

* Command-line tool "isabelle build_docker" builds a Docker image from
the Isabelle application bundle for Linux. See also

* Command-line tool "isabelle vscode_server" provides a Language Server
Protocol implementation, e.g. for the Visual Studio Code editor. It
serves as example for alternative PIDE front-ends.

* Command-line tool "isabelle imports" helps to maintain theory imports
wrt. session structure. Examples for the main Isabelle distribution:

  isabelle imports -I -a
  isabelle imports -U -a
  isabelle imports -U -i -a
  isabelle imports -M -a -d '~~/src/Benchmarks'

New in Isabelle2016-1 (December 2016)

*** General ***

* Splitter in proof methods "simp", "auto" and friends:
  - The syntax "split add" has been discontinued, use plain "split",
  - For situations with many conditional or case expressions, there is
    an alternative splitting strategy that can be much faster. It is
    selected by writing "split!" instead of "split". It applies safe
    introduction and elimination rules after each split rule. As a
    result the subgoal may be split into several subgoals.

* Command 'bundle' provides a local theory target to define a bundle
from the body of specification commands (such as 'declare',
'declaration', 'notation', 'lemmas', 'lemma'). For example:

bundle foo
  declare a [simp]
  declare b [intro]

* Command 'unbundle' is like 'include', but works within a local theory
context. Unlike "context includes ... begin", the effect of 'unbundle'
on the target context persists, until different declarations are given.

* Simplified outer syntax: uniform category "name" includes long
identifiers. Former "xname" / "nameref" / "name reference" has been

* Embedded content (e.g. the inner syntax of types, terms, props) may be
delimited uniformly via cartouches. This works better than old-fashioned
quotes when sub-languages are nested.

* Mixfix annotations support general block properties, with syntax
"(\<open>x=a y=b z \<dots>\<close>". Notable property names are "indent", "consistent",
"unbreakable", "markup". The existing notation "(DIGITS" is equivalent
to "(\<open>indent=DIGITS\<close>". The former notation "(00" for unbreakable blocks
is superseded by "(\<open>unbreabable\<close>" --- rare INCOMPATIBILITY.

* Proof method "blast" is more robust wrt. corner cases of Pure
statements without object-logic judgment.

* Commands 'prf' and 'full_prf' are somewhat more informative (again):
proof terms are reconstructed and cleaned from administrative thm nodes.

* Code generator: config option "code_timing" triggers measurements of
different phases of code generation. See src/HOL/ex/Code_Timing.thy for

* Code generator: implicits in Scala (stemming from type class
instances) are generated into companion object of corresponding type
class, to resolve some situations where ambiguities may occur.

* Solve direct: option "solve_direct_strict_warnings" gives explicit
warnings for lemma statements with trivial proofs.

*** Prover IDE -- Isabelle/Scala/jEdit ***

* More aggressive flushing of machine-generated input, according to
system option editor_generated_input_delay (in addition to existing
editor_input_delay for regular user edits). This may affect overall PIDE
reactivity and CPU usage.

* Syntactic indentation according to Isabelle outer syntax. Action
"indent-lines" (shortcut C+i) indents the current line according to
command keywords and some command substructure. Action
"isabelle.newline" (shortcut ENTER) indents the old and the new line
according to command keywords only; see also option

* Semantic indentation for unstructured proof scripts ('apply' etc.) via
number of subgoals. This requires information of ongoing document
processing and may thus lag behind, when the user is editing too
quickly; see also option "jedit_script_indent" and

* Refined folding mode "isabelle" based on Isar syntax: 'next' and 'qed'
are treated as delimiters for fold structure; 'begin' and 'end'
structure of theory specifications is treated as well.

* Command 'proof' provides information about proof outline with cases,
e.g. for proof methods "cases", "induct", "goal_cases".

* Completion templates for commands involving "begin ... end" blocks,
e.g. 'context', 'notepad'.

* Sidekick parser "isabelle-context" shows nesting of context blocks
according to 'begin' and 'end' structure.

* Highlighting of entity def/ref positions wrt. cursor.

* Action "" (shortcut CS+ENTER) selects all
occurrences of the formal entity at the caret position. This facilitates
systematic renaming.

* PIDE document markup works across multiple Isar commands, e.g. the
results established at the end of a proof are properly identified in the
theorem statement.

* Cartouche abbreviations work both for " and ` to accomodate typical
situations where old ASCII notation may be updated.

* Dockable window "Symbols" also provides access to 'abbrevs' from the
outer syntax of the current theory buffer. This provides clickable
syntax templates, including entries with empty abbrevs name (which are
inaccessible via keyboard completion).

* IDE support for the Isabelle/Pure bootstrap process, with the
following independent stages:


The ML ROOT files act like quasi-theories in the context of theory
ML_Bootstrap: this allows continuous checking of all loaded ML files.
The theory files are presented with a modified header to import Pure
from the running Isabelle instance. Results from changed versions of
each stage are *not* propagated to the next stage, and isolated from the
actual Isabelle/Pure that runs the IDE itself. The sequential
dependencies of the above files are only observed for batch build.

* Isabelle/ML and Standard ML files are presented in Sidekick with the
tree structure of section headings: this special comment format is
described in "implementation" chapter 0, e.g. (*** section ***).

* Additional abbreviations for syntactic completion may be specified
within the theory header as 'abbrevs'. The theory syntax for 'keywords'
has been simplified accordingly: optional abbrevs need to go into the
new 'abbrevs' section.

* Global abbreviations via $ISABELLE_HOME/etc/abbrevs and
$ISABELLE_HOME_USER/etc/abbrevs are no longer supported. Minor
INCOMPATIBILITY, use 'abbrevs' within theory header instead.

* Action "isabelle.keymap-merge" asks the user to resolve pending
Isabelle keymap changes that are in conflict with the current jEdit
keymap; non-conflicting changes are always applied implicitly. This
action is automatically invoked on Isabelle/jEdit startup and thus
increases chances that users see new keyboard shortcuts when re-using
old keymaps.

* ML and document antiquotations for file-systems paths are more uniform
and diverse:

  @{path NAME}   -- no file-system check
  @{file NAME}   -- check for plain file
  @{dir NAME}    -- check for directory

Minor INCOMPATIBILITY, former uses of @{file} and @{file_unchecked} may
have to be changed.

*** Document preparation ***

* New symbol \<circle>, e.g. for temporal operator.

* New document and ML antiquotation @{locale} for locales, similar to
existing antiquotation @{class}.

* Mixfix annotations support delimiters like \<^control>\<open>cartouche\<close> --
this allows special forms of document output.

* Raw LaTeX output now works via \<^latex>\<open>...\<close> instead of raw control
symbol \<^raw:...>. INCOMPATIBILITY, notably for LaTeXsugar.thy and its

* \<^raw:...> symbols are no longer supported.

* Old 'header' command is no longer supported (legacy since

*** Isar ***

* Many specification elements support structured statements with 'if' /
'for' eigen-context, e.g. 'axiomatization', 'abbreviation',
'definition', 'inductive', 'function'.

* Toplevel theorem statements support eigen-context notation with 'if' /
'for' (in postfix), which corresponds to 'assumes' / 'fixes' in the
traditional long statement form (in prefix). Local premises are called
"that" or "assms", respectively. Empty premises are *not* bound in the

* Command 'define' introduces a local (non-polymorphic) definition, with
optional abstraction over local parameters. The syntax resembles
'definition' and 'obtain'. It fits better into the Isar language than
old 'def', which is now a legacy feature.

* Command 'obtain' supports structured statements with 'if' / 'for'

* Command '\<proof>' is an alias for 'sorry', with different
typesetting. E.g. to produce proof holes in examples and documentation.

* The defining position of a literal fact \<open>prop\<close> is maintained more
carefully, and made accessible as hyperlink in the Prover IDE.

* Commands 'finally' and 'ultimately' used to expose the result as
literal fact: this accidental behaviour has been discontinued. Rare
INCOMPATIBILITY, use more explicit means to refer to facts in Isar.

* Command 'axiomatization' has become more restrictive to correspond
better to internal axioms as singleton facts with mandatory name. Minor

* Proof methods may refer to the main facts via the dynamic fact
"method_facts". This is particularly useful for Eisbach method

* Proof method "use" allows to modify the main facts of a given method
expression, e.g.

  (use facts in simp)
  (use facts in \<open>simp add: ...\<close>)

* The old proof method "default" has been removed (legacy since
Isabelle2016). INCOMPATIBILITY, use "standard" instead.

*** Pure ***

* Pure provides basic versions of proof methods "simp" and "simp_all"
that only know about meta-equality (==). Potential INCOMPATIBILITY in
theory imports that merge Pure with e.g. Main of Isabelle/HOL: the order
is relevant to avoid confusion of Pure.simp vs. HOL.simp.

* The command 'unfolding' and proof method "unfold" include a second
stage where given equations are passed through the attribute "abs_def"
before rewriting. This ensures that definitions are fully expanded,
regardless of the actual parameters that are provided. Rare
INCOMPATIBILITY in some corner cases: use proof method (simp only:)
instead, or declare [[unfold_abs_def = false]] in the proof context.

* Type-inference improves sorts of newly introduced type variables for
the object-logic, using its base sort (i.e. HOL.type for Isabelle/HOL).
Thus terms like "f x" or "\<And>x. P x" without any further syntactic context
produce x::'a::type in HOL instead of x::'a::{} in Pure. Rare
INCOMPATIBILITY, need to provide explicit type constraints for Pure
types where this is really intended.

*** HOL ***

* New proof method "argo" using the built-in Argo solver based on SMT
technology. The method can be used to prove goals of quantifier-free
propositional logic, goals based on a combination of quantifier-free
propositional logic with equality, and goals based on a combination of
quantifier-free propositional logic with linear real arithmetic
including min/max/abs. See HOL/ex/Argo_Examples.thy for examples.

* The new "nunchaku" command integrates the Nunchaku model finder. The
tool is experimental. See ~~/src/HOL/Nunchaku/Nunchaku.thy for details.

* Metis: The problem encoding has changed very slightly. This might
break existing proofs. INCOMPATIBILITY.

* Sledgehammer:
  - The MaSh relevance filter is now faster than before.
  - Produce syntactically correct Vampire 4.0 problem files.

* (Co)datatype package:
  - New commands for defining corecursive functions and reasoning about
    them in "~~/src/HOL/Library/BNF_Corec.thy": 'corec', 'corecursive',
    'friend_of_corec', and 'corecursion_upto'; and 'corec_unique' proof
    method. See 'isabelle doc corec'.
  - The predicator :: ('a \<Rightarrow> bool) \<Rightarrow> 'a F \<Rightarrow> bool is now a first-class
    citizen in bounded natural functors.
  - 'primrec' now allows nested calls through the predicator in addition
    to the map function.
  - 'bnf' automatically discharges reflexive proof obligations.
  - 'bnf' outputs a slightly modified proof obligation expressing rel in
       terms of map and set
       (not giving a specification for rel makes this one reflexive).
  - 'bnf' outputs a new proof obligation expressing pred in terms of set
       (not giving a specification for pred makes this one reflexive).
    INCOMPATIBILITY: manual 'bnf' declarations may need adjustment.
  - Renamed lemmas:
      rel_prod_apply ~> rel_prod_inject
      pred_prod_apply ~> pred_prod_inject
  - The "size" plugin has been made compatible again with locales.
  - The theorems about "rel" and "set" may have a slightly different (but
    equivalent) form.

* The 'coinductive' command produces a proper coinduction rule for
mutual coinductive predicates. This new rule replaces the old rule,
which exposed details of the internal fixpoint construction and was

* New abbreviations for negated existence (but not bounded existence):

  \<nexists>x. P x \<equiv> \<not> (\<exists>x. P x)
  \<nexists>!x. P x \<equiv> \<not> (\<exists>!x. P x)

* The print mode "HOL" for ASCII syntax of binders "!", "?", "?!", "@"
has been removed for output. It is retained for input only, until it is
eliminated altogether.

* The unique existence quantifier no longer provides 'binder' syntax,
but uses syntax translations (as for bounded unique existence). Thus
iterated quantification \<exists>!x y. P x y with its slightly confusing
sequential meaning \<exists>!x. \<exists>!y. P x y is no longer possible. Instead,
pattern abstraction admits simultaneous unique existence \<exists>!(x, y). P x y
(analogous to existing notation \<exists>!(x, y)\<in>A. P x y). Potential
INCOMPATIBILITY in rare situations.

* Conventional syntax "%(). t" for unit abstractions. Slight syntactic

* Renamed constants and corresponding theorems:

    setsum ~> sum
    setprod ~> prod
    listsum ~> sum_list
    listprod ~> prod_list


* Sligthly more standardized theorem names:
    sgn_times ~> sgn_mult
    sgn_mult' ~> Real_Vector_Spaces.sgn_mult
    divide_zero_left ~> div_0
    zero_mod_left ~> mod_0
    divide_zero ~> div_by_0
    divide_1 ~> div_by_1
    nonzero_mult_divide_cancel_left ~> nonzero_mult_div_cancel_left
    div_mult_self1_is_id ~> nonzero_mult_div_cancel_left
    nonzero_mult_divide_cancel_right ~> nonzero_mult_div_cancel_right
    div_mult_self2_is_id ~> nonzero_mult_div_cancel_right
    is_unit_divide_mult_cancel_left ~> is_unit_div_mult_cancel_left
    is_unit_divide_mult_cancel_right ~> is_unit_div_mult_cancel_right
    mod_div_equality ~> div_mult_mod_eq
    mod_div_equality2 ~> mult_div_mod_eq
    mod_div_equality3 ~> mod_div_mult_eq
    mod_div_equality4 ~> mod_mult_div_eq
    minus_div_eq_mod ~> minus_div_mult_eq_mod
    minus_div_eq_mod2 ~> minus_mult_div_eq_mod
    minus_mod_eq_div ~> minus_mod_eq_div_mult
    minus_mod_eq_div2 ~> minus_mod_eq_mult_div
    div_mod_equality' ~> minus_mod_eq_div_mult [symmetric]
    mod_div_equality' ~> minus_div_mult_eq_mod [symmetric]
    zmod_zdiv_equality ~> mult_div_mod_eq [symmetric]
    zmod_zdiv_equality' ~> minus_div_mult_eq_mod [symmetric]
    Divides.mult_div_cancel ~> minus_mod_eq_mult_div [symmetric]
    mult_div_cancel ~> minus_mod_eq_mult_div [symmetric]
    zmult_div_cancel ~> minus_mod_eq_mult_div [symmetric]
    div_1 ~> div_by_Suc_0
    mod_1 ~> mod_by_Suc_0

* New type class "idom_abs_sgn" specifies algebraic properties
of sign and absolute value functions.  Type class "sgn_if" has
disappeared.  Slight INCOMPATIBILITY.

* Dedicated syntax LENGTH('a) for length of types.

* Characters (type char) are modelled as finite algebraic type
corresponding to {0..255}.

  - Logical representation:
    * 0 is instantiated to the ASCII zero character.
    * All other characters are represented as "Char n"
      with n being a raw numeral expression less than 256.
    * Expressions of the form "Char n" with n greater than 255
      are non-canonical.
  - Printing and parsing:
    * Printable characters are printed and parsed as "CHR ''\<dots>''"
      (as before).
    * The ASCII zero character is printed and parsed as "0".
    * All other canonical characters are printed as "CHR 0xXX"
      with XX being the hexadecimal character code.  "CHR n"
      is parsable for every numeral expression n.
    * Non-canonical characters have no special syntax and are
      printed as their logical representation.
  - Explicit conversions from and to the natural numbers are
    provided as char_of_nat, nat_of_char (as before).
  - The auxiliary nibble type has been discontinued.


* Type class "div" with operation "mod" renamed to type class "modulo"
with operation "modulo", analogously to type class "divide". This
eliminates the need to qualify any of those names in the presence of
infix "mod" syntax. INCOMPATIBILITY.

* Statements and proofs of Knaster-Tarski fixpoint combinators lfp/gfp
have been clarified. The fixpoint properties are lfp_fixpoint, its
symmetric lfp_unfold (as before), and the duals for gfp. Auxiliary items
for the proof (lfp_lemma2 etc.) are no longer exported, but can be
easily recovered by composition with eq_refl. Minor INCOMPATIBILITY.

* Constant "surj" is a mere input abbreviation, to avoid hiding an
equation in term output. Minor INCOMPATIBILITY.

* Command 'code_reflect' accepts empty constructor lists for datatypes,
which renders those abstract effectively.

* Command 'export_code' checks given constants for abstraction
violations: a small guarantee that given constants specify a safe
interface for the generated code.

* Code generation for Scala: ambiguous implicts in class diagrams are
spelt out explicitly.

* Static evaluators (Code_Evaluation.static_* in Isabelle/ML) rely on
explicitly provided auxiliary definitions for required type class
dictionaries rather than half-working magic. INCOMPATIBILITY, see the
tutorial on code generation for details.

* Theory Set_Interval: substantial new theorems on indexed sums and

* Locale bijection establishes convenient default simp rules such as
"inv f (f a) = a" for total bijections.

* Abstract locales semigroup, abel_semigroup, semilattice,
semilattice_neutr, ordering, ordering_top, semilattice_order,
semilattice_neutr_order, comm_monoid_set, semilattice_set,
semilattice_neutr_set, semilattice_order_set,
semilattice_order_neutr_set monoid_list, comm_monoid_list,
comm_monoid_list_set, comm_monoid_mset, comm_monoid_fun use boldified
syntax uniformly that does not clash with corresponding global syntax.

* Former locale lifting_syntax is now a bundle, which is easier to
include in a local context or theorem statement, e.g. "context includes
lifting_syntax begin ... end". Minor INCOMPATIBILITY.

* Some old / obsolete theorems have been renamed / removed, potential

  nat_less_cases  --  removed, use linorder_cases instead
  inv_image_comp  --  removed, use image_inv_f_f instead
  image_surj_f_inv_f  ~>  image_f_inv_f

* Some theorems about groups and orders have been generalised from
  groups to semi-groups that are also monoids:

* Some simplifications theorems about rings have been removed, since
  superseeded by a more general version:
    less_add_cancel_left_greater_zero ~> less_add_same_cancel1
    less_add_cancel_right_greater_zero ~> less_add_same_cancel2
    less_eq_add_cancel_left_greater_eq_zero ~> le_add_same_cancel1
    less_eq_add_cancel_right_greater_eq_zero ~> le_add_same_cancel2
    less_eq_add_cancel_left_less_eq_zero ~> add_le_same_cancel1
    less_eq_add_cancel_right_less_eq_zero ~> add_le_same_cancel2
    less_add_cancel_left_less_zero ~> add_less_same_cancel1
    less_add_cancel_right_less_zero ~> add_less_same_cancel2

* Renamed split_if -> if_split and split_if_asm -> if_split_asm to
resemble the f.split naming convention, INCOMPATIBILITY.

* Added class topological_monoid.

* The following theorems have been renamed:

  setsum_left_distrib ~> sum_distrib_right
  setsum_right_distrib ~> sum_distrib_left


* Compound constants INFIMUM and SUPREMUM are mere abbreviations now.

* "Gcd (f ` A)" and "Lcm (f ` A)" are printed with optional
comprehension-like syntax analogously to "Inf (f ` A)" and "Sup (f `

* Class semiring_Lcd merged into semiring_Gcd. INCOMPATIBILITY.

* The type class ordered_comm_monoid_add is now called
ordered_cancel_comm_monoid_add. A new type class ordered_comm_monoid_add
is introduced as the combination of ordered_ab_semigroup_add +
comm_monoid_add. INCOMPATIBILITY.

* Introduced the type classes canonically_ordered_comm_monoid_add and

* Introduced the type class ordered_ab_semigroup_monoid_add_imp_le. When
instantiating linordered_semiring_strict and ordered_ab_group_add, an
explicit instantiation of ordered_ab_semigroup_monoid_add_imp_le might

* Dropped various legacy fact bindings, whose replacements are often
of a more general type also:
  lcm_left_commute_nat ~> lcm.left_commute
  lcm_left_commute_int ~> lcm.left_commute
  gcd_left_commute_nat ~> gcd.left_commute
  gcd_left_commute_int ~> gcd.left_commute
  gcd_greatest_iff_nat ~> gcd_greatest_iff
  gcd_greatest_iff_int ~> gcd_greatest_iff
  coprime_dvd_mult_nat ~> coprime_dvd_mult
  coprime_dvd_mult_int ~> coprime_dvd_mult
  zpower_numeral_even ~> power_numeral_even
  gcd_mult_cancel_nat ~> gcd_mult_cancel
  gcd_mult_cancel_int ~> gcd_mult_cancel
  div_gcd_coprime_nat ~> div_gcd_coprime
  div_gcd_coprime_int ~> div_gcd_coprime
  zpower_numeral_odd ~> power_numeral_odd
  zero_less_int_conv ~> of_nat_0_less_iff
  gcd_greatest_nat ~> gcd_greatest
  gcd_greatest_int ~> gcd_greatest
  coprime_mult_nat ~> coprime_mult
  coprime_mult_int ~> coprime_mult
  lcm_commute_nat ~> lcm.commute
  lcm_commute_int ~> lcm.commute
  int_less_0_conv ~> of_nat_less_0_iff
  gcd_commute_nat ~> gcd.commute
  gcd_commute_int ~> gcd.commute
  Gcd_insert_nat ~> Gcd_insert
  Gcd_insert_int ~> Gcd_insert
  of_int_int_eq ~> of_int_of_nat_eq
  lcm_least_nat ~> lcm_least
  lcm_least_int ~> lcm_least
  lcm_assoc_nat ~> lcm.assoc
  lcm_assoc_int ~> lcm.assoc
  int_le_0_conv ~> of_nat_le_0_iff
  int_eq_0_conv ~> of_nat_eq_0_iff
  Gcd_empty_nat ~> Gcd_empty
  Gcd_empty_int ~> Gcd_empty
  gcd_assoc_nat ~> gcd.assoc
  gcd_assoc_int ~> gcd.assoc
  zero_zle_int ~> of_nat_0_le_iff
  lcm_dvd2_nat ~> dvd_lcm2
  lcm_dvd2_int ~> dvd_lcm2
  lcm_dvd1_nat ~> dvd_lcm1
  lcm_dvd1_int ~> dvd_lcm1
  gcd_zero_nat ~> gcd_eq_0_iff
  gcd_zero_int ~> gcd_eq_0_iff
  gcd_dvd2_nat ~> gcd_dvd2
  gcd_dvd2_int ~> gcd_dvd2
  gcd_dvd1_nat ~> gcd_dvd1
  gcd_dvd1_int ~> gcd_dvd1
  int_numeral ~> of_nat_numeral
  lcm_ac_nat ~> ac_simps
  lcm_ac_int ~> ac_simps
  gcd_ac_nat ~> ac_simps
  gcd_ac_int ~> ac_simps
  abs_int_eq ~> abs_of_nat
  zless_int ~> of_nat_less_iff
  zdiff_int ~> of_nat_diff
  zadd_int ~> of_nat_add
  int_mult ~> of_nat_mult
  int_Suc ~> of_nat_Suc
  inj_int ~> inj_of_nat
  int_1 ~> of_nat_1
  int_0 ~> of_nat_0
  Lcm_empty_nat ~> Lcm_empty
  Lcm_empty_int ~> Lcm_empty
  Lcm_insert_nat ~> Lcm_insert
  Lcm_insert_int ~> Lcm_insert
  comp_fun_idem_gcd_nat ~> comp_fun_idem_gcd
  comp_fun_idem_gcd_int ~> comp_fun_idem_gcd
  comp_fun_idem_lcm_nat ~> comp_fun_idem_lcm
  comp_fun_idem_lcm_int ~> comp_fun_idem_lcm
  Lcm_eq_0 ~> Lcm_eq_0_I
  Lcm0_iff ~> Lcm_0_iff
  Lcm_dvd_int ~> Lcm_least
  divides_mult_nat ~> divides_mult
  divides_mult_int ~> divides_mult
  lcm_0_nat ~> lcm_0_right
  lcm_0_int ~> lcm_0_right
  lcm_0_left_nat ~> lcm_0_left
  lcm_0_left_int ~> lcm_0_left
  dvd_gcd_D1_nat ~> dvd_gcdD1
  dvd_gcd_D1_int ~> dvd_gcdD1
  dvd_gcd_D2_nat ~> dvd_gcdD2
  dvd_gcd_D2_int ~> dvd_gcdD2
  coprime_dvd_mult_iff_nat ~> coprime_dvd_mult_iff
  coprime_dvd_mult_iff_int ~> coprime_dvd_mult_iff
  realpow_minus_mult ~> power_minus_mult
  realpow_Suc_le_self ~> power_Suc_le_self
  dvd_Gcd, dvd_Gcd_nat, dvd_Gcd_int removed in favour of Gcd_greatest

* Renamed HOL/Quotient_Examples/FSet.thy to
HOL/Quotient_Examples/Quotient_FSet.thy INCOMPATIBILITY.

* Session HOL-Library: theory FinFun bundles "finfun_syntax" and
"no_finfun_syntax" allow to control optional syntax in local contexts;
this supersedes former theory FinFun_Syntax. INCOMPATIBILITY, e.g. use
"unbundle finfun_syntax" to imitate import of

* Session HOL-Library: theory Multiset_Permutations (executably) defines
the set of permutations of a given set or multiset, i.e. the set of all
lists that contain every element of the carrier (multi-)set exactly

* Session HOL-Library: multiset membership is now expressed using
set_mset rather than count.

  - Expressions "count M a > 0" and similar simplify to membership
    by default.

  - Converting between "count M a = 0" and non-membership happens using
    equations count_eq_zero_iff and not_in_iff.

  - Rules count_inI and in_countE obtain facts of the form
    "count M a = n" from membership.

  - Rules count_in_diffI and in_diff_countE obtain facts of the form
    "count M a = n + count N a" from membership on difference sets.


* Session HOL-Library: theory LaTeXsugar uses new-style "dummy_pats" for
displaying equations in functional programming style --- variables
present on the left-hand but not on the righ-hand side are replaced by

* Session HOL-Library: theory Combinator_PER provides combinator to
build partial equivalence relations from a predicate and an equivalence

* Session HOL-Library: theory Perm provides basic facts about almost
everywhere fix bijections.

* Session HOL-Library: theory Normalized_Fraction allows viewing an
element of a field of fractions as a normalized fraction (i.e. a pair of
numerator and denominator such that the two are coprime and the
denominator is normalized wrt. unit factors).

* Session HOL-NSA has been renamed to HOL-Nonstandard_Analysis.

* Session HOL-Multivariate_Analysis has been renamed to HOL-Analysis.

* Session HOL-Analysis: measure theory has been moved here from
HOL-Probability. When importing HOL-Analysis some theorems need
additional name spaces prefixes due to name clashes. INCOMPATIBILITY.

* Session HOL-Analysis: more complex analysis including Cauchy's
inequality, Liouville theorem, open mapping theorem, maximum modulus
principle, Residue theorem, Schwarz Lemma.

* Session HOL-Analysis: Theory of polyhedra: faces, extreme points,
polytopes, and the Krein–Milman Minkowski theorem.

* Session HOL-Analysis: Numerous results ported from the HOL Light
libraries: homeomorphisms, continuous function extensions, invariance of

* Session HOL-Probability: the type of emeasure and nn_integral was
changed from ereal to ennreal, INCOMPATIBILITY.

  emeasure :: 'a measure \<Rightarrow> 'a set \<Rightarrow> ennreal
  nn_integral :: 'a measure \<Rightarrow> ('a \<Rightarrow> ennreal) \<Rightarrow> ennreal

* Session HOL-Probability: Code generation and QuickCheck for
Probability Mass Functions.

* Session HOL-Probability: theory Random_Permutations contains some
theory about choosing a permutation of a set uniformly at random and
folding over a list in random order.

* Session HOL-Probability: theory SPMF formalises discrete
subprobability distributions.

* Session HOL-Library: the names of multiset theorems have been
normalised to distinguish which ordering the theorems are about

    mset_less_eqI ~> mset_subset_eqI
    mset_less_insertD ~> mset_subset_insertD
    mset_less_eq_count ~> mset_subset_eq_count
    mset_less_diff_self ~> mset_subset_diff_self
    mset_le_exists_conv ~> mset_subset_eq_exists_conv
    mset_le_mono_add_right_cancel ~> mset_subset_eq_mono_add_right_cancel
    mset_le_mono_add_left_cancel ~> mset_subset_eq_mono_add_left_cancel
    mset_le_mono_add ~> mset_subset_eq_mono_add
    mset_le_add_left ~> mset_subset_eq_add_left
    mset_le_add_right ~> mset_subset_eq_add_right
    mset_le_single ~> mset_subset_eq_single
    mset_le_multiset_union_diff_commute ~> mset_subset_eq_multiset_union_diff_commute
    diff_le_self ~> diff_subset_eq_self
    mset_leD ~> mset_subset_eqD
    mset_lessD ~> mset_subsetD
    mset_le_insertD ~> mset_subset_eq_insertD
    mset_less_of_empty ~> mset_subset_of_empty
    mset_less_size ~> mset_subset_size
    wf_less_mset_rel ~> wf_subset_mset_rel
    count_le_replicate_mset_le ~> count_le_replicate_mset_subset_eq
    mset_remdups_le ~> mset_remdups_subset_eq
    ms_lesseq_impl ~> subset_eq_mset_impl

Some functions have been renamed:
    ms_lesseq_impl -> subset_eq_mset_impl

* HOL-Library: multisets are now ordered with the multiset ordering
    #\<subseteq># ~> \<le>
    #\<subset># ~> <
    le_multiset ~> less_eq_multiset
    less_multiset ~> le_multiset

* Session HOL-Library: the prefix multiset_order has been discontinued:
the theorems can be directly accessed. As a consequence, the lemmas
"order_multiset" and "linorder_multiset" have been discontinued, and the
interpretations "multiset_linorder" and "multiset_wellorder" have been
replaced by instantiations. INCOMPATIBILITY.

* Session HOL-Library: some theorems about the multiset ordering have
been renamed:

    le_multiset_def ~> less_eq_multiset_def
    less_multiset_def ~> le_multiset_def
    less_eq_imp_le_multiset ~> subset_eq_imp_le_multiset
    mult_less_not_refl ~> mset_le_not_refl
    mult_less_trans ~> mset_le_trans
    mult_less_not_sym ~> mset_le_not_sym
    mult_less_asym ~> mset_le_asym
    mult_less_irrefl ~> mset_le_irrefl
    union_less_mono2{,1,2} ~> union_le_mono2{,1,2}

    le_multiset\<^sub>H\<^sub>O ~> less_eq_multiset\<^sub>H\<^sub>O
    le_multiset_total ~> less_eq_multiset_total
    less_multiset_right_total ~> subset_eq_imp_le_multiset
    le_multiset_empty_left ~> less_eq_multiset_empty_left
    le_multiset_empty_right ~> less_eq_multiset_empty_right
    less_multiset_empty_right ~> le_multiset_empty_left
    less_multiset_empty_left ~> le_multiset_empty_right
    union_less_diff_plus ~> union_le_diff_plus
    ex_gt_count_imp_less_multiset ~> ex_gt_count_imp_le_multiset
    less_multiset_plus_left_nonempty ~> le_multiset_plus_left_nonempty
    le_multiset_plus_right_nonempty ~> le_multiset_plus_right_nonempty

* Session HOL-Library: the lemma mset_map has now the attribute [simp].

* Session HOL-Library: some theorems about multisets have been removed.
INCOMPATIBILITY, use the following replacements:

    le_multiset_plus_plus_left_iff ~> add_less_cancel_right
    less_multiset_plus_plus_left_iff ~> add_less_cancel_right
    le_multiset_plus_plus_right_iff ~> add_less_cancel_left
    less_multiset_plus_plus_right_iff ~> add_less_cancel_left
    add_eq_self_empty_iff ~> add_cancel_left_right
    mset_subset_add_bothsides ~> subset_mset.add_less_cancel_right
    mset_less_add_bothsides ~> subset_mset.add_less_cancel_right
    mset_le_add_bothsides ~> subset_mset.add_less_cancel_right
    empty_inter ~> subset_mset.inf_bot_left
    inter_empty ~> subset_mset.inf_bot_right
    empty_sup ~> subset_mset.sup_bot_left
    sup_empty ~> subset_mset.sup_bot_right
    bdd_below_multiset ~> subset_mset.bdd_above_bot
    subset_eq_empty ~> subset_mset.le_zero_eq
    le_empty ~> subset_mset.le_zero_eq
    mset_subset_empty_nonempty ~> subset_mset.zero_less_iff_neq_zero
    mset_less_empty_nonempty ~> subset_mset.zero_less_iff_neq_zero

* Session HOL-Library: some typeclass constraints about multisets have
been reduced from ordered or linordered to preorder. Multisets have the
additional typeclasses order_bot, no_top,
ordered_ab_semigroup_add_imp_le, ordered_cancel_comm_monoid_add,
linordered_cancel_ab_semigroup_add, and
ordered_ab_semigroup_monoid_add_imp_le. INCOMPATIBILITY.

* Session HOL-Library: there are some new simplification rules about
multisets, the multiset ordering, and the subset ordering on multisets.

* Session HOL-Library: the subset ordering on multisets has now the
interpretations ordered_ab_semigroup_monoid_add_imp_le and
bounded_lattice_bot. INCOMPATIBILITY.

* Session HOL-Library, theory Multiset: single has been removed in favor
of add_mset that roughly corresponds to Set.insert. Some theorems have
removed or changed:

  single_not_empty ~> add_mset_not_empty or empty_not_add_mset
  fold_mset_insert ~> fold_mset_add_mset
  image_mset_insert ~> image_mset_add_mset

* Session HOL-Library, theory Multiset: some theorems have been changed
to use add_mset instead of single:


* Session HOL-Library, theory Multiset: the definitions of some
constants have changed to use add_mset instead of adding a single



* Session HOL-Library, theory Multiset: due to the above changes, the
attributes of some multiset theorems have been changed:

  insert_DiffM  [] ~> [simp]
  insert_DiffM2 [simp] ~> []
  diff_add_mset_swap [simp]
  fold_mset_add_mset [simp]
  diff_diff_add [simp] (for multisets only)
  diff_cancel [simp] ~> []
  count_single [simp] ~> []
  set_mset_single [simp] ~> []
  size_multiset_single [simp] ~> []
  size_single [simp] ~> []
  image_mset_single [simp] ~> []
  mset_subset_eq_mono_add_right_cancel [simp] ~> []
  mset_subset_eq_mono_add_left_cancel [simp] ~> []
  fold_mset_single [simp] ~> []
  subset_eq_empty [simp] ~> []
  empty_sup [simp] ~> []
  sup_empty [simp] ~> []
  inter_empty [simp] ~> []
  empty_inter [simp] ~> []

* Session HOL-Library, theory Multiset: the order of the variables in
the second cases of multiset_induct, multiset_induct2_size,
multiset_induct2 has been changed (e.g. Add A a ~> Add a A).

* Session HOL-Library, theory Multiset: there is now a simplification
procedure on multisets. It mimics the behavior of the procedure on
natural numbers. INCOMPATIBILITY.

* Session HOL-Library, theory Multiset: renamed sums and products of

  msetsum ~> sum_mset
  msetprod ~> prod_mset

* Session HOL-Library, theory Multiset: the notation for intersection
and union of multisets have been changed:

  #\<inter> ~> \<inter>#
  #\<union> ~> \<union>#


* Session HOL-Library, theory Multiset: the lemma
one_step_implies_mult_aux on multisets has been removed, use
one_step_implies_mult instead. INCOMPATIBILITY.

* Session HOL-Library: theory Complete_Partial_Order2 provides reasoning
support for monotonicity and continuity in chain-complete partial orders
and about admissibility conditions for fixpoint inductions.

* Session HOL-Library: theory Library/Polynomial contains also
derivation of polynomials (formerly in Library/Poly_Deriv) but not
gcd/lcm on polynomials over fields. This has been moved to a separate
theory Library/Polynomial_GCD_euclidean.thy, to pave way for a possible
future different type class instantiation for polynomials over factorial

* Session HOL-Library: theory Sublist provides function "prefixes" with
the following renaming

  prefixeq -> prefix
  prefix -> strict_prefix
  suffixeq -> suffix
  suffix -> strict_suffix

Added theory of longest common prefixes.

* Session HOL-Number_Theory: algebraic foundation for primes:
Generalisation of predicate "prime" and introduction of predicates
"prime_elem", "irreducible", a "prime_factorization" function, and the
"factorial_ring" typeclass with instance proofs for nat, int, poly. Some
theorems now have different names, most notably "prime_def" is now
"prime_nat_iff". INCOMPATIBILITY.

* Session Old_Number_Theory has been removed, after porting remaining

* Session HOL-Types_To_Sets provides an experimental extension of
Higher-Order Logic to allow translation of types to sets.

*** ML ***

* Integer.gcd and Integer.lcm use efficient operations from the Poly/ML
library (notably for big integers). Subtle change of semantics:
Integer.gcd and Integer.lcm both normalize the sign, results are never
negative. This coincides with the definitions in HOL/GCD.thy.

* Structure Rat for rational numbers is now an integral part of
Isabelle/ML, with special notation @int/nat or @int for numerals (an
abbreviation for antiquotation @{Pure.rat argument}) and ML pretty
printing. Standard operations on type Rat.rat are provided via ad-hoc
overloading of + - * / < <= > >= ~ abs. INCOMPATIBILITY, need to
use + instead of +/ etc. Moreover, exception Rat.DIVZERO has been
superseded by General.Div.

* ML antiquotation @{path} is superseded by @{file}, which ensures that
the argument is a plain file. Minor INCOMPATIBILITY.

* Antiquotation @{make_string} is available during Pure bootstrap --
with approximative output quality.

* Low-level ML system structures (like PolyML and RunCall) are no longer
exposed to Isabelle/ML user-space. Potential INCOMPATIBILITY.

* The ML function "ML" provides easy access to run-time compilation.
This is particularly useful for conditional compilation, without
requiring separate files.

* Option ML_exception_debugger controls detailed exception trace via the
Poly/ML debugger. Relevant ML modules need to be compiled beforehand
with ML_file_debug, or with ML_file and option ML_debugger enabled. Note
debugger information requires consirable time and space: main
Isabelle/HOL with full debugger support may need ML_system_64.

* Local_Theory.restore has been renamed to Local_Theory.reset to
emphasize its disruptive impact on the cumulative context, notably the
scope of 'private' or 'qualified' names. Note that Local_Theory.reset is
only appropriate when targets are managed, e.g. starting from a global
theory and returning to it. Regular definitional packages should use
balanced blocks of Local_Theory.open_target versus
Local_Theory.close_target instead. Rare INCOMPATIBILITY.

* Structure TimeLimit (originally from the SML/NJ library) has been
replaced by structure Timeout, with slightly different signature.

* Discontinued cd and pwd operations, which are not well-defined in a
multi-threaded environment. Note that files are usually located
relatively to the master directory of a theory (see also
File.full_path). Potential INCOMPATIBILITY.

* Binding.empty_atts supersedes Thm.empty_binding and
Attrib.empty_binding. Minor INCOMPATIBILITY.

*** System ***

* SML/NJ and old versions of Poly/ML are no longer supported.

* Poly/ML heaps now follow the hierarchy of sessions, and thus require
much less disk space.

* The Isabelle ML process is now managed directly by Isabelle/Scala, and
shell scripts merely provide optional command-line access. In

  . Scala module ML_Process to connect to the raw ML process,
    with interaction via stdin/stdout/stderr or in batch mode;
  . command-line tool "isabelle console" as interactive wrapper;
  . command-line tool "isabelle process" as batch mode wrapper.

* The executable "isabelle_process" has been discontinued. Tools and
prover front-ends should use ML_Process or Isabelle_Process in

* New command-line tool "isabelle process" supports ML evaluation of
literal expressions (option -e) or files (option -f) in the context of a
given heap image. Errors lead to premature exit of the ML process with
return code 1.

* The command-line tool "isabelle build" supports option -N for cyclic
shuffling of NUMA CPU nodes. This may help performance tuning on Linux
servers with separate CPU/memory modules.

* System option "threads" (for the size of the Isabelle/ML thread farm)
is also passed to the underlying ML runtime system as --gcthreads,
unless there is already a default provided via ML_OPTIONS settings.

* System option "checkpoint" helps to fine-tune the global heap space
management of isabelle build. This is relevant for big sessions that may
exhaust the small 32-bit address space of the ML process (which is used
by default).

* System option "profiling" specifies the mode for global ML profiling
in "isabelle build". Possible values are "time", "allocations". The
command-line tool "isabelle profiling_report" helps to digest the
resulting log files.

* System option "ML_process_policy" specifies an optional command prefix
for the underlying ML process, e.g. to control CPU affinity on
multiprocessor systems. The "isabelle jedit" tool allows to override the
implicit default via option -p.

* Command-line tool "isabelle console" provides option -r to help to
bootstrapping Isabelle/Pure interactively.

* Command-line tool "isabelle yxml" has been discontinued.
INCOMPATIBILITY, use operations from the modules "XML" and "YXML" in
Isabelle/ML or Isabelle/Scala.

* Many Isabelle tools that require a Java runtime system refer to the
depending on the underlying platform. The settings for "isabelle build"
discontinued. Potential INCOMPATIBILITY.

* The Isabelle system environment always ensures that the main
executables are found within the shell search $PATH: "isabelle" and

* Isabelle tools may consist of .scala files: the Scala compiler is
invoked on the spot. The source needs to define some object that extends

* File.bash_string, File.bash_path etc. represent Isabelle/ML and
Isabelle/Scala strings authentically within GNU bash. This is useful to
produce robust shell scripts under program control, without worrying
about spaces or special characters. Note that user output works via
Path.print (ML) or Path.toString (Scala). INCOMPATIBILITY, the old (and
less versatile) operations File.shell_quote, File.shell_path etc. have
been discontinued.

* The isabelle_java executable allows to run a Java process within the
name space of Java and Scala components that are bundled with Isabelle,
but without the Isabelle settings environment.

* Isabelle/Scala: the SSH module supports ssh and sftp connections, for
remote command-execution and file-system access. This resembles
operations from module File and Isabelle_System to some extent. Note
that Path specifications need to be resolved remotely via
ssh.remote_path instead of File.standard_path: the implicit process
environment is different, Isabelle settings are not available remotely.

* Isabelle/Scala: the Mercurial module supports repositories via the
regular hg command-line interface. The repositroy clone and working
directory may reside on a local or remote file-system (via ssh

New in Isabelle2016 (February 2016)

*** General ***

* Eisbach is now based on Pure instead of HOL. Objects-logics may import
either the theory ~~/src/HOL/Eisbach/Eisbach (for HOL etc.) or
~~/src/HOL/Eisbach/Eisbach_Old_Appl_Syntax (for FOL, ZF etc.). Note that
the HOL-Eisbach session located in ~~/src/HOL/Eisbach/ contains further
examples that do require HOL.

* Better resource usage on all platforms (Linux, Windows, Mac OS X) for
both Isabelle/ML and Isabelle/Scala.  Slightly reduced heap space usage.

* Former "xsymbols" syntax with Isabelle symbols is used by default,
without any special print mode. Important ASCII replacement syntax
remains available under print mode "ASCII", but less important syntax
has been removed (see below).

* Support for more arrow symbols, with rendering in LaTeX and Isabelle
fonts: \<Lleftarrow> \<Rrightarrow> \<longlongleftarrow> \<longlongrightarrow> \<longlonglongleftarrow> \<longlonglongrightarrow>.

* Special notation \<struct> for the first implicit 'structure' in the
context has been discontinued. Rare INCOMPATIBILITY, use explicit
structure name instead, notably in indexed notation with block-subscript
(e.g. \<odot>\<^bsub>A\<^esub>).

* The glyph for \<diamond> in the IsabelleText font now corresponds better to its
counterpart \<box> as quantifier-like symbol. A small diamond is available as
\<diamondop>; the old symbol \<struct> loses this rendering and any special

* Syntax for formal comments "-- text" now also supports the symbolic
form "\<comment> text". Command-line tool "isabelle update_cartouches -c" helps
to update old sources.

* Toplevel theorem statements have been simplified as follows:

  theorems             ~>  lemmas
  schematic_lemma      ~>  schematic_goal
  schematic_theorem    ~>  schematic_goal
  schematic_corollary  ~>  schematic_goal

Command-line tool "isabelle update_theorems" updates theory sources

* Toplevel theorem statement 'proposition' is another alias for

* The old 'defs' command has been removed (legacy since Isabelle2014).
INCOMPATIBILITY, use regular 'definition' instead. Overloaded and/or
deferred definitions require a surrounding 'overloading' block.

*** Prover IDE -- Isabelle/Scala/jEdit ***

* IDE support for the source-level debugger of Poly/ML, to work with
Isabelle/ML and official Standard ML. Option "ML_debugger" and commands
'ML_file_debug', 'ML_file_no_debug', 'SML_file_debug',
'SML_file_no_debug' control compilation of sources with or without
debugging information. The Debugger panel allows to set breakpoints (via
context menu), step through stopped threads, evaluate local ML
expressions etc. At least one Debugger view needs to be active to have
any effect on the running ML program.

* The State panel manages explicit proof state output, with dynamic
auto-update according to cursor movement. Alternatively, the jEdit
action "isabelle.update-state" (shortcut S+ENTER) triggers manual

* The Output panel no longer shows proof state output by default, to
avoid GUI overcrowding. INCOMPATIBILITY, use the State panel instead or
enable option "editor_output_state".

* The text overview column (status of errors, warnings etc.) is updated
asynchronously, leading to much better editor reactivity. Moreover, the
full document node content is taken into account. The width of the
column is scaled according to the main text area font, for improved

* The main text area no longer changes its color hue in outdated
situations. The text overview column takes over the role to indicate
unfinished edits in the PIDE pipeline. This avoids flashing text display
due to ad-hoc updates by auxiliary GUI components, such as the State

* Slightly improved scheduling for urgent print tasks (e.g. command
state output, interactive queries) wrt. long-running background tasks.

* Completion of symbols via prefix of \<name> or \<^name> or \name is
always possible, independently of the language context. It is never
implicit: a popup will show up unconditionally.

* Additional abbreviations for syntactic completion may be specified in
$ISABELLE_HOME/etc/abbrevs and $ISABELLE_HOME_USER/etc/abbrevs, with
support for simple templates using ASCII 007 (bell) as placeholder.

* Symbols \<oplus>, \<Oplus>, \<otimes>, \<Otimes>, \<odot>, \<Odot>, \<ominus>, \<oslash> no longer provide abbreviations for
completion like "+o", "*o", ".o" etc. -- due to conflicts with other
ASCII syntax. INCOMPATIBILITY, use plain backslash-completion or define
suitable abbreviations in $ISABELLE_HOME_USER/etc/abbrevs.

* Action "isabelle-emph" (with keyboard shortcut C+e LEFT) controls
emphasized text style; the effect is visible in document output, not in
the editor.

* Action "isabelle-reset" now uses keyboard shortcut C+e BACK_SPACE,
instead of former C+e LEFT.

* The command-line tool "isabelle jedit" and the isabelle.Main
application wrapper treat the default $USER_HOME/Scratch.thy more
uniformly, and allow the dummy file argument ":" to open an empty buffer

* New command-line tool "isabelle jedit_client" allows to connect to an
already running Isabelle/jEdit process. This achieves the effect of
single-instance applications seen on common GUI desktops.

* The default look-and-feel for Linux is the traditional "Metal", which
works better with GUI scaling for very high-resolution displays (e.g.
4K). Moreover, it is generally more robust than "Nimbus".

* Update to jedit-5.3.0, with improved GUI scaling and support of
high-resolution displays (e.g. 4K).

* The main Isabelle executable is managed as single-instance Desktop
application uniformly on all platforms: Linux, Windows, Mac OS X.

*** Document preparation ***

* Commands 'paragraph' and 'subparagraph' provide additional section
headings. Thus there are 6 levels of standard headings, as in HTML.

* Command 'text_raw' has been clarified: input text is processed as in
'text' (with antiquotations and control symbols). The key difference is
the lack of the surrounding isabelle markup environment in output.

* Text is structured in paragraphs and nested lists, using notation that
is similar to Markdown. The control symbols for list items are as

  \<^item>  itemize
  \<^enum>  enumerate
  \<^descr>  description

* There is a new short form for antiquotations with a single argument
that is a cartouche: \<^name>\<open>...\<close> is equivalent to @{name \<open>...\<close>} and
\<open>...\<close> without control symbol is equivalent to @{cartouche \<open>...\<close>}.
\<^name> without following cartouche is equivalent to @{name}. The
standard Isabelle fonts provide glyphs to render important control
symbols, e.g. "\<^verbatim>", "\<^emph>", "\<^bold>".

* Antiquotations @{noindent}, @{smallskip}, @{medskip}, @{bigskip} with
corresponding control symbols \<^noindent>, \<^smallskip>, \<^medskip>, \<^bigskip> specify spacing formally, using
standard LaTeX macros of the same names.

* Antiquotation @{cartouche} in Isabelle/Pure is the same as @{text}.
Consequently, \<open>...\<close> without any decoration prints literal quasi-formal
text. Command-line tool "isabelle update_cartouches -t" helps to update
old sources, by approximative patching of the content of string and
cartouche tokens seen in theory sources.

* The @{text} antiquotation now ignores the antiquotation option
"source". The given text content is output unconditionally, without any
surrounding quotes etc. Subtle INCOMPATIBILITY, put quotes into the
argument where they are really intended, e.g. @{text \<open>"foo"\<close>}. Initial
or terminal spaces are ignored.

* Antiquotations @{emph} and @{bold} output LaTeX source recursively,
adding appropriate text style markup. These may be used in the short
form \<^emph>\<open>...\<close> and \<^bold>\<open>...\<close>.

* Document antiquotation @{footnote} outputs LaTeX source recursively,
marked as \footnote{}. This may be used in the short form \<^footnote>\<open>...\<close>.

* Antiquotation @{verbatim [display]} supports option "indent".

* Antiquotation @{theory_text} prints uninterpreted theory source text
(Isar outer syntax with command keywords etc.). This may be used in the
short form \<^theory_text>\<open>...\<close>. @{theory_text [display]} supports option "indent".

* Antiquotation @{doc ENTRY} provides a reference to the given
documentation, with a hyperlink in the Prover IDE.

* Antiquotations @{command}, @{method}, @{attribute} print checked
entities of the Isar language.

* HTML presentation uses the standard IsabelleText font and Unicode
rendering of Isabelle symbols like Isabelle/Scala/jEdit.  The former
print mode "HTML" loses its special meaning.

*** Isar ***

* Local goals ('have', 'show', 'hence', 'thus') allow structured rule
statements like fixes/assumes/shows in theorem specifications, but the
notation is postfix with keywords 'if' (or 'when') and 'for'. For

  have result: "C x y"
    if "A x" and "B y"
    for x :: 'a and y :: 'a

The local assumptions are bound to the name "that". The result is
exported from context of the statement as usual. The above roughly
corresponds to a raw proof block like this:

    fix x :: 'a and y :: 'a
    assume that: "A x" "B y"
    have "C x y" <proof>
  note result = this

The keyword 'when' may be used instead of 'if', to indicate 'presume'
instead of 'assume' above.

* Assumptions ('assume', 'presume') allow structured rule statements
using 'if' and 'for', similar to 'have' etc. above. For example:

  assume result: "C x y"
    if "A x" and "B y"
    for x :: 'a and y :: 'a

This assumes "\<And>x y::'a. A x \<Longrightarrow> B y \<Longrightarrow> C x y" and produces a general
result as usual: "A ?x \<Longrightarrow> B ?y \<Longrightarrow> C ?x ?y".

Vacuous quantification in assumptions is omitted, i.e. a for-context
only effects propositions according to actual use of variables. For

  assume "A x" and "B y" for x and y

is equivalent to:

  assume "\<And>x. A x" and "\<And>y. B y"

* The meaning of 'show' with Pure rule statements has changed: premises
are treated in the sense of 'assume', instead of 'presume'. This means,
a goal like "\<And>x. A x \<Longrightarrow> B x \<Longrightarrow> C x" can be solved completely as

  show "\<And>x. A x \<Longrightarrow> B x \<Longrightarrow> C x"


  show "C x" if "A x" "B x" for x

Rare INCOMPATIBILITY, the old behaviour may be recovered as follows:

  show "C x" when "A x" "B x" for x

* New command 'consider' states rules for generalized elimination and
case splitting. This is like a toplevel statement "theorem obtains" used
within a proof body; or like a multi-branch 'obtain' without activation
of the local context elements yet.

* Proof method "cases" allows to specify the rule as first entry of
chained facts.  This is particularly useful with 'consider':

  consider (a) A | (b) B | (c) C <proof>
  then have something
  proof cases
    case a
    then show ?thesis <proof>
    case b
    then show ?thesis <proof>
    case c
    then show ?thesis <proof>

* Command 'case' allows fact name and attribute specification like this:

  case a: (c xs)
  case a [attributes]: (c xs)

Facts that are introduced by invoking the case context are uniformly
qualified by "a"; the same name is used for the cumulative fact. The old
form "case (c xs) [attributes]" is no longer supported. Rare
INCOMPATIBILITY, need to adapt uses of case facts in exotic situations,
and always put attributes in front.

* The standard proof method of commands 'proof' and '..' is now called
"standard" to make semantically clear what it is; the old name "default"
is still available as legacy for some time. Documentation now explains
'..' more accurately as "by standard" instead of "by rule".

* Nesting of Isar goal structure has been clarified: the context after
the initial backwards refinement is retained for the whole proof, within
all its context sections (as indicated via 'next'). This is e.g.
relevant for 'using', 'including', 'supply':

  have "A \<and> A" if a: A for A
    supply [simp] = a
    show A by simp
    show A by simp

* Command 'obtain' binds term abbreviations (via 'is' patterns) in the
proof body as well, abstracted over relevant parameters.

* Improved type-inference for theorem statement 'obtains': separate
parameter scope for of each clause.

* Term abbreviations via 'is' patterns also work for schematic
statements: result is abstracted over unknowns.

* Command 'subgoal' allows to impose some structure on backward
refinements, to avoid proof scripts degenerating into long of 'apply'
sequences. Further explanations and examples are given in the isar-ref

* Command 'supply' supports fact definitions during goal refinement
('apply' scripts).

* Proof method "goal_cases" turns the current subgoals into cases within
the context; the conclusion is bound to variable ?case in each case. For

lemma "\<And>x. A x \<Longrightarrow> B x \<Longrightarrow> C x"
  and "\<And>y z. U y \<Longrightarrow> V z \<Longrightarrow> W y z"
proof goal_cases
  case (1 x)
  then show ?case using \<open>A x\<close> \<open>B x\<close> sorry
  case (2 y z)
  then show ?case using \<open>U y\<close> \<open>V z\<close> sorry

lemma "\<And>x. A x \<Longrightarrow> B x \<Longrightarrow> C x"
  and "\<And>y z. U y \<Longrightarrow> V z \<Longrightarrow> W y z"
proof goal_cases
  case prems: 1
  then show ?case using prems sorry
  case prems: 2
  then show ?case using prems sorry

* The undocumented feature of implicit cases goal1, goal2, goal3, etc.
is marked as legacy, and will be removed eventually. The proof method
"goals" achieves a similar effect within regular Isar; often it can be
done more adequately by other means (e.g. 'consider').

* The vacuous fact "TERM x" may be established "by fact" or as `TERM x`
as well, not just "by this" or "." as before.

* Method "sleep" succeeds after a real-time delay (in seconds). This is
occasionally useful for demonstration and testing purposes.

*** Pure ***

* Qualifiers in locale expressions default to mandatory ('!') regardless
of the command. Previously, for 'locale' and 'sublocale' the default was
optional ('?'). The old synatx '!' has been discontinued.
INCOMPATIBILITY, remove '!' and add '?' as required.

* Keyword 'rewrites' identifies rewrite morphisms in interpretation
commands. Previously, the keyword was 'where'. INCOMPATIBILITY.

* More gentle suppression of syntax along locale morphisms while
printing terms. Previously 'abbreviation' and 'notation' declarations
would be suppressed for morphisms except term identity. Now
'abbreviation' is also kept for morphims that only change the involved
parameters, and only 'notation' is suppressed. This can be of great help
when working with complex locale hierarchies, because proof states are
displayed much more succinctly. It also means that only notation needs
to be redeclared if desired, as illustrated by this example:

  locale struct = fixes composition :: "'a => 'a => 'a" (infixl "\<cdot>" 65)
    definition derived (infixl "\<odot>" 65) where ...

  locale morphism =
    left: struct composition + right: struct composition'
    for composition (infix "\<cdot>" 65) and composition' (infix "\<cdot>''" 65)
    notation right.derived ("\<odot>''")

* Command 'global_interpretation' issues interpretations into global
theories, with optional rewrite definitions following keyword 'defines'.

* Command 'sublocale' accepts optional rewrite definitions after keyword

* Command 'permanent_interpretation' has been discontinued. Use
'global_interpretation' or 'sublocale' instead. INCOMPATIBILITY.

* Command 'print_definitions' prints dependencies of definitional
specifications. This functionality used to be part of 'print_theory'.

* Configuration option rule_insts_schematic has been discontinued
(intermediate legacy feature in Isabelle2015). INCOMPATIBILITY.

* Abbreviations in type classes now carry proper sort constraint. Rare
INCOMPATIBILITY in situations where the previous misbehaviour has been

* Refinement of user-space type system in type classes: pseudo-local
operations behave more similar to abbreviations. Potential
INCOMPATIBILITY in exotic situations.

*** HOL ***

* The 'typedef' command has been upgraded from a partially checked
"axiomatization", to a full definitional specification that takes the
global collection of overloaded constant / type definitions into
account. Type definitions with open dependencies on overloaded
definitions need to be specified as "typedef (overloaded)". This
provides extra robustness in theory construction. Rare INCOMPATIBILITY.

* Qualification of various formal entities in the libraries is done more
uniformly via "context begin qualified definition ... end" instead of
old-style "hide_const (open) ...". Consequently, both the defined
constant and its defining fact become qualified, e.g. Option.is_none and
Option.is_none_def. Occasional INCOMPATIBILITY in applications.

* Some old and rarely used ASCII replacement syntax has been removed.
INCOMPATIBILITY, standard syntax with symbols should be used instead.
The subsequent commands help to reproduce the old forms, e.g. to
simplify porting old theories:

  notation iff  (infixr "<->" 25)

  notation Times  (infixr "<*>" 80)

  type_notation  (infixr "~=>" 0)
  notation Map.map_comp  (infixl "o'_m" 55)

  type_notation FinFun.finfun ("(_ =>f /_)" [22, 21] 21)

  notation FuncSet.funcset  (infixr "->" 60)
  notation FuncSet.extensional_funcset  (infixr "->\<^sub>E" 60)

  notation Omega_Words_Fun.conc (infixr "conc" 65)

  notation Preorder.equiv ("op ~~")
    and Preorder.equiv ("(_/ ~~ _)" [51, 51] 50)

  notation (in topological_space) tendsto (infixr "--->" 55)
  notation (in topological_space) LIMSEQ ("((_)/ ----> (_))" [60, 60] 60)
  notation LIM ("((_)/ -- (_)/ --> (_))" [60, 0, 60] 60)

  notation NSA.approx (infixl "@=" 50)
  notation NSLIMSEQ ("((_)/ ----NS> (_))" [60, 60] 60)
  notation NSLIM ("((_)/ -- (_)/ --NS> (_))" [60, 0, 60] 60)

* The alternative notation "\<Colon>" for type and sort constraints has been
removed: in LaTeX document output it looks the same as "::".
INCOMPATIBILITY, use plain "::" instead.

* Commands 'inductive' and 'inductive_set' work better when names for
intro rules are omitted: the "cases" and "induct" rules no longer
declare empty case_names, but no case_names at all. This allows to use
numbered cases in proofs, without requiring method "goal_cases".

* Inductive definitions ('inductive', 'coinductive', etc.) expose
low-level facts of the internal construction only if the option
"inductive_internals" is enabled. This refers to the internal predicate
definition and its monotonicity result. Rare INCOMPATIBILITY.

* Recursive function definitions ('fun', 'function', 'partial_function')
expose low-level facts of the internal construction only if the option
"function_internals" is enabled. Its internal inductive definition is
also subject to "inductive_internals". Rare INCOMPATIBILITY.

* BNF datatypes ('datatype', 'codatatype', etc.) expose low-level facts
of the internal construction only if the option "bnf_internals" is
enabled. This supersedes the former option "bnf_note_all". Rare

* Combinator to represent case distinction on products is named
"case_prod", uniformly, discontinuing any input aliasses. Very popular
theorem aliasses have been retained.

Consolidated facts:
  PairE ~> prod.exhaust
  Pair_eq ~> prod.inject
  pair_collapse ~> prod.collapse
  Pair_fst_snd_eq ~> prod_eq_iff
  split_twice ~> prod.case_distrib
  split_weak_cong ~> prod.case_cong_weak
  split_split ~> prod.split
  split_split_asm ~> prod.split_asm
  splitI ~> case_prodI
  splitD ~> case_prodD
  splitI2 ~> case_prodI2
  splitI2' ~> case_prodI2'
  splitE ~> case_prodE
  splitE' ~> case_prodE'
  split_pair ~> case_prod_Pair
  split_eta ~> case_prod_eta
  split_comp ~> case_prod_comp
  mem_splitI ~> mem_case_prodI
  mem_splitI2 ~> mem_case_prodI2
  mem_splitE ~> mem_case_prodE
  The_split ~> The_case_prod
  cond_split_eta ~> cond_case_prod_eta
  Collect_split_in_rel_leE ~> Collect_case_prod_in_rel_leE
  Collect_split_in_rel_leI ~> Collect_case_prod_in_rel_leI
  in_rel_Collect_split_eq ~> in_rel_Collect_case_prod_eq
  Collect_split_Grp_eqD ~> Collect_case_prod_Grp_eqD
  Collect_split_Grp_inD ~> Collect_case_prod_Grp_in
  Domain_Collect_split ~> Domain_Collect_case_prod
  Image_Collect_split ~> Image_Collect_case_prod
  Range_Collect_split ~> Range_Collect_case_prod
  Eps_split ~> Eps_case_prod
  Eps_split_eq ~> Eps_case_prod_eq
  split_rsp ~> case_prod_rsp
  curry_split ~> curry_case_prod
  split_curry ~> case_prod_curry

Changes in structure HOLogic:
  split_const ~> case_prod_const
  mk_split ~> mk_case_prod
  mk_psplits ~> mk_ptupleabs
  strip_psplits ~> strip_ptupleabs


* The coercions to type 'real' have been reorganised. The function
'real' is no longer overloaded, but has type 'nat => real' and
abbreviates of_nat for that type. Also 'real_of_int :: int => real'
abbreviates of_int for that type. Other overloaded instances of 'real'
have been replaced by 'real_of_ereal' and 'real_of_float'.

Consolidated facts (among others):
  real_of_nat_le_iff -> of_nat_le_iff
  real_of_nat_numeral of_nat_numeral
  real_of_int_zero of_int_0
  real_of_nat_zero of_nat_0
  real_of_one of_int_1
  real_of_int_add of_int_add
  real_of_nat_add of_nat_add
  real_of_int_diff of_int_diff
  real_of_nat_diff of_nat_diff
  floor_subtract floor_diff_of_int
  real_of_int_inject of_int_eq_iff
  real_of_int_gt_zero_cancel_iff of_int_0_less_iff
  real_of_int_ge_zero_cancel_iff of_int_0_le_iff
  real_of_nat_ge_zero of_nat_0_le_iff
  real_of_int_ceiling_ge le_of_int_ceiling
  ceiling_less_eq ceiling_less_iff
  ceiling_le_eq ceiling_le_iff
  less_floor_eq less_floor_iff
  floor_less_eq floor_less_iff
  floor_divide_eq_div floor_divide_of_int_eq
  real_of_int_zero_cancel of_nat_eq_0_iff
  ceiling_real_of_int ceiling_of_int


* Theory Map: lemma map_of_is_SomeD was a clone of map_of_SomeD and has
been removed. INCOMPATIBILITY.

* Quickcheck setup for finite sets.

* Discontinued simp_legacy_precond. Potential INCOMPATIBILITY.

* Sledgehammer:
  - The MaSh relevance filter has been sped up.
  - Proof reconstruction has been improved, to minimize the incidence of
    cases where Sledgehammer gives a proof that does not work.
  - Auto Sledgehammer now minimizes and preplays the results.
  - Handle Vampire 4.0 proof output without raising exception.
  - Eliminated "MASH" environment variable. Use the "MaSh" option in
    Isabelle/jEdit instead. INCOMPATIBILITY.
  - Eliminated obsolete "blocking" option and related subcommands.

* Nitpick:
  - Fixed soundness bug in translation of "finite" predicate.
  - Fixed soundness bug in "destroy_constrs" optimization.
  - Fixed soundness bug in translation of "rat" type.
  - Removed "check_potential" and "check_genuine" options.
  - Eliminated obsolete "blocking" option.

* (Co)datatype package:
  - New commands "lift_bnf" and "copy_bnf" for lifting (copying) a BNF
    structure on the raw type to an abstract type defined using typedef.
  - Always generate "case_transfer" theorem.
  - For mutual types, generate slightly stronger "rel_induct",
    "rel_coinduct", and "coinduct" theorems. INCOMPATIBILITY.
  - Allow discriminators and selectors with the same name as the type
    being defined.
  - Avoid various internal name clashes (e.g., 'datatype f = f').

* Transfer: new methods for interactive debugging of 'transfer' and
'transfer_prover': 'transfer_start', 'transfer_step', 'transfer_end',
'transfer_prover_start' and 'transfer_prover_end'.

* New diagnostic command print_record for displaying record definitions.

* Division on integers is bootstrapped directly from division on
naturals and uses generic numeral algorithm for computations. Slight
INCOMPATIBILITY, simproc numeral_divmod replaces and generalizes former
simprocs binary_int_div and binary_int_mod

* Tightened specification of class semiring_no_zero_divisors. Minor

* Class algebraic_semidom introduces common algebraic notions of
integral (semi)domains, particularly units. Although logically subsumed
by fields, is is not a super class of these in order not to burden
fields with notions that are trivial there.

* Class normalization_semidom specifies canonical representants for
equivalence classes of associated elements in an integral (semi)domain.
This formalizes associated elements as well.

* Abstract specification of gcd/lcm operations in classes semiring_gcd,
semiring_Gcd, semiring_Lcd. Minor INCOMPATIBILITY: facts gcd_nat.commute
and gcd_int.commute are subsumed by gcd.commute, as well as
gcd_nat.assoc and gcd_int.assoc by gcd.assoc.

* Former constants Fields.divide (_ / _) and Divides.div (_ div _) are
logically unified to Rings.divide in syntactic type class Rings.divide,
with infix syntax (_ div _). Infix syntax (_ / _) for field division is
added later as abbreviation in class Fields.inverse. INCOMPATIBILITY,
instantiations must refer to Rings.divide rather than the former
separate constants, hence infix syntax (_ / _) is usually not available
during instantiation.

* New cancellation simprocs for boolean algebras to cancel complementary
terms for sup and inf. For example, "sup x (sup y (- x))" simplifies to

* Class uniform_space introduces uniform spaces btw topological spaces
and metric spaces. Minor INCOMPATIBILITY: open_<type>_def needs to be
introduced in the form of an uniformity. Some constants are more general
now, it may be necessary to add type class constraints.

  open_real_def \<leadsto> open_dist
  open_complex_def \<leadsto> open_dist

* Library/Monad_Syntax: notation uses symbols \<bind> and \<then>. INCOMPATIBILITY.

* Library/Multiset:
  - Renamed multiset inclusion operators:
      < ~> <#
      > ~> >#
      <= ~> <=#
      >= ~> >=#
      \<le> ~> \<le>#
      \<ge> ~> \<ge>#
  - Added multiset inclusion operator syntax:
  - "'a multiset" is no longer an instance of the "order",
    "ordered_ab_semigroup_add_imp_le", "ordered_cancel_comm_monoid_diff",
    "semilattice_inf", and "semilattice_sup" type classes. The theorems
    previously provided by these type classes (directly or indirectly)
    are now available through the "subset_mset" interpretation
    (e.g. add_mono ~> subset_mset.add_mono).
  - Renamed conversions:
      multiset_of ~> mset
      multiset_of_set ~> mset_set
      set_of ~> set_mset
  - Renamed lemmas:
      mset_le_def ~> subseteq_mset_def
      mset_less_def ~> subset_mset_def
      less_eq_multiset.rep_eq ~> subseteq_mset_def
  - Removed lemmas generated by lift_definition:
    less_eq_multiset.abs_eq, less_eq_multiset.rsp,
    less_eq_multiset.transfer, less_eq_multiset_def

* Library/Omega_Words_Fun: Infinite words modeled as functions nat \<Rightarrow> 'a.

* Library/Bourbaki_Witt_Fixpoint: Added formalisation of the
Bourbaki-Witt fixpoint theorem for increasing functions in
chain-complete partial orders.

* Library/Old_Recdef: discontinued obsolete 'defer_recdef' command.
Minor INCOMPATIBILITY, use 'function' instead.

* Library/Periodic_Fun: a locale that provides convenient lemmas for
periodic functions.

* Library/Formal_Power_Series: proper definition of division (with
remainder) for formal power series; instances for Euclidean Ring and

* HOL-Imperative_HOL: obsolete theory Legacy_Mrec has been removed.

* HOL-Statespace: command 'statespace' uses mandatory qualifier for
import of parent, as for general 'locale' expressions. INCOMPATIBILITY,
remove '!' and add '?' as required.

* HOL-Decision_Procs: The "approximation" method works with "powr"
(exponentiation on real numbers) again.

* HOL-Multivariate_Analysis: theory Cauchy_Integral_Thm with Contour
integrals (= complex path integrals), Cauchy's integral theorem, winding
numbers and Cauchy's integral formula, Liouville theorem, Fundamental
Theorem of Algebra. Ported from HOL Light.

* HOL-Multivariate_Analysis: topological concepts such as connected
components, homotopic paths and the inside or outside of a set.

* HOL-Multivariate_Analysis: radius of convergence of power series and
various summability tests; Harmonic numbers and the Euler–Mascheroni
constant; the Generalised Binomial Theorem; the complex and real
Gamma/log-Gamma/Digamma/ Polygamma functions and their most important

* HOL-Probability: The central limit theorem based on Levy's uniqueness
and continuity theorems, weak convergence, and characterisitc functions.

* HOL-Data_Structures: new and growing session of standard data

*** ML ***

* The following combinators for low-level profiling of the ML runtime
system are available:

  profile_time          (*CPU time*)
  profile_time_thread   (*CPU time on this thread*)
  profile_allocations   (*overall heap allocations*)

* Antiquotation @{undefined} or \<^undefined> inlines (raise Match).

* Antiquotation @{method NAME} inlines the (checked) name of the given
Isar proof method.

* Pretty printing of Poly/ML compiler output in Isabelle has been
improved: proper treatment of break offsets and blocks with consistent

* The auxiliary module Pure/display.ML has been eliminated. Its
elementary thm print operations are now in Pure/more_thm.ML and thus
called Thm.pretty_thm, Thm.string_of_thm etc. INCOMPATIBILITY.

* Simproc programming interfaces have been simplified:
Simplifier.make_simproc and Simplifier.define_simproc supersede various
forms of Simplifier.mk_simproc, Simplifier.simproc_global etc. Note that
term patterns for the left-hand sides are specified with implicitly
fixed variables, like top-level theorem statements. INCOMPATIBILITY.

* Instantiation rules have been re-organized as follows:

  Thm.instantiate  (*low-level instantiation with named arguments*)
  Thm.instantiate' (*version with positional arguments*)

  Drule.infer_instantiate  (*instantiation with type inference*)
  Drule.infer_instantiate'  (*version with positional arguments*)

The LHS only requires variable specifications, instead of full terms.
Old cterm_instantiate is superseded by infer_instantiate.
INCOMPATIBILITY, need to re-adjust some ML names and types accordingly.

* Old tactic shorthands atac, rtac, etac, dtac, ftac have been
discontinued. INCOMPATIBILITY, use regular assume_tac, resolve_tac etc.
instead (with proper context).

* Thm.instantiate (and derivatives) no longer require the LHS of the
instantiation to be certified: plain variables are given directly.

* Subgoal.SUBPROOF and Subgoal.FOCUS combinators use anonymous
quasi-bound variables (like the Simplifier), instead of accidentally
named local fixes. This has the potential to improve stability of proof
tools, but can also cause INCOMPATIBILITY for tools that don't observe
the proof context discipline.

* Isar proof methods are based on a slightly more general type
context_tactic, which allows to change the proof context dynamically
(e.g. to update cases) and indicate explicit Seq.Error results. Former
METHOD_CASES is superseded by CONTEXT_METHOD; further combinators are
provided in src/Pure/Isar/method.ML for convenience. INCOMPATIBILITY.

*** System ***

* Command-line tool "isabelle console" enables print mode "ASCII".

* Command-line tool "isabelle update_then" expands old Isar command

    hence  ~>  then have
    thus   ~>  then show

This syntax is more orthogonal and improves readability and
maintainability of proofs.

* Global session timeout is multiplied by timeout_scale factor. This
allows to adjust large-scale tests (e.g. AFP) to overall hardware

* Property values in etc/symbols may contain spaces, if written with the
replacement character "␣" (Unicode point 0x2324). For example:

    \<star>  code: 0x0022c6  group: operator  font: Deja␣Vu␣Sans␣Mono

* Java runtime environment for x86_64-windows allows to use larger heap

* Java runtime options are determined separately for 32bit vs. 64bit
platforms as follows.

  - Isabelle desktop application: platform-specific files that are
    associated with the main app bundle

  - isabelle jedit: settings

  - isabelle build: settings

* Bash shell function "jvmpath" has been renamed to "platform_path": it
is relevant both for Poly/ML and JVM processes.

* Poly/ML default platform architecture may be changed from 32bit to
64bit via system option ML_system_64. A system restart (and rebuild) is
required after change.

* Poly/ML 5.6 runs natively on x86-windows and x86_64-windows, which
both allow larger heap space than former x86-cygwin.

* Heap images are 10-15% smaller due to less wasteful persistent theory
content (using ML type theory_id instead of theory);

New in Isabelle2015 (May 2015)

*** General ***

* Local theory specification commands may have a 'private' or
'qualified' modifier to restrict name space accesses to the local scope,
as provided by some "context begin ... end" block. For example:


  private definition ...
  private lemma ...

  qualified definition ...
  qualified lemma ...

  lemma ...
  theorem ...


* Command 'experiment' opens an anonymous locale context with private
naming policy.

* Command 'notepad' requires proper nesting of begin/end and its proof
structure in the body: 'oops' is no longer supported here. Minor
INCOMPATIBILITY, use 'sorry' instead.

* Command 'named_theorems' declares a dynamic fact within the context,
together with an attribute to maintain the content incrementally. This
supersedes functor Named_Thms in Isabelle/ML, but with a subtle change
of semantics due to external visual order vs. internal reverse order.

* 'find_theorems': search patterns which are abstractions are
schematically expanded before search. Search results match the naive
expectation more closely, particularly wrt. abbreviations.

* Commands 'method_setup' and 'attribute_setup' now work within a local
theory context.

* Outer syntax commands are managed authentically within the theory
context, without implicit global state. Potential for accidental
INCOMPATIBILITY, make sure that required theories are really imported.

* Historical command-line terminator ";" is no longer accepted (and
already used differently in Isar). Minor INCOMPATIBILITY, use "isabelle
update_semicolons" to remove obsolete semicolons from old theory

* Structural composition of proof methods (meth1; meth2) in Isar
corresponds to (tac1 THEN_ALL_NEW tac2) in ML.

* The Eisbach proof method language allows to define new proof methods
by combining existing ones with their usual syntax. The "match" proof
method provides basic fact/term matching in addition to
premise/conclusion matching through Subgoal.focus, and binds fact names
from matches as well as term patterns within matches. The Isabelle
documentation provides an entry "eisbach" for the Eisbach User Manual.
Sources and various examples are in ~~/src/HOL/Eisbach/.

*** Prover IDE -- Isabelle/Scala/jEdit ***

* Improved folding mode "isabelle" based on Isar syntax. Alternatively,
the "sidekick" mode may be used for document structure.

* Extended bracket matching based on Isar language structure. System
option jedit_structure_limit determines maximum number of lines to scan
in the buffer.

* Support for BibTeX files: context menu, context-sensitive token
marker, SideKick parser.

* Document antiquotation @{cite} provides formal markup, which is
interpreted semi-formally based on .bib files that happen to be open in
the editor (hyperlinks, completion etc.).

* Less waste of vertical space via negative line spacing (see Global
Options / Text Area).

* Improved graphview panel with optional output of PNG or PDF, for
display of 'thy_deps', 'class_deps' etc.

* The commands 'thy_deps' and 'class_deps' allow optional bounds to
restrict the visualized hierarchy.

* Improved scheduling for asynchronous print commands (e.g. provers
managed by the Sledgehammer panel) wrt. ongoing document processing.

*** Document preparation ***

* Document markup commands 'chapter', 'section', 'subsection',
'subsubsection', 'text', 'txt', 'text_raw' work uniformly in any
context, even before the initial 'theory' command. Obsolete proof
commands 'sect', 'subsect', 'subsubsect', 'txt_raw' have been
discontinued, use 'section', 'subsection', 'subsubsection', 'text_raw'
instead. The old 'header' command is still retained for some time, but
should be replaced by 'chapter', 'section' etc. (using "isabelle
update_header"). Minor INCOMPATIBILITY.

* Official support for "tt" style variants, via \isatt{...} or
\begin{isabellett}...\end{isabellett}. The somewhat fragile \verb or
verbatim environment of LaTeX is no longer used. This allows @{ML} etc.
as argument to other macros (such as footnotes).

* Document antiquotation @{verbatim} prints ASCII text literally in "tt"

* Discontinued obsolete option "document_graph": session_graph.pdf is
produced unconditionally for HTML browser_info and PDF-LaTeX document.

* Diagnostic commands and document markup commands within a proof do not
affect the command tag for output. Thus commands like 'thm' are subject
to proof document structure, and no longer "stick out" accidentally.
Commands 'text' and 'txt' merely differ in the LaTeX style, not their
tags. Potential INCOMPATIBILITY in exotic situations.

* System option "pretty_margin" is superseded by "thy_output_margin",
which is also accessible via document antiquotation option "margin".
Only the margin for document output may be changed, but not the global
pretty printing: that is 76 for plain console output, and adapted
dynamically in GUI front-ends. Implementations of document
antiquotations need to observe the margin explicitly according to
Thy_Output.string_of_margin. Minor INCOMPATIBILITY.

* Specification of 'document_files' in the session ROOT file is
mandatory for document preparation. The legacy mode with implicit
copying of the document/ directory is no longer supported. Minor

*** Pure ***

* Proof methods with explicit instantiation ("rule_tac", "subgoal_tac"
etc.) allow an optional context of local variables ('for' declaration):
these variables become schematic in the instantiated theorem; this
behaviour is analogous to 'for' in attributes "where" and "of".
Configuration option rule_insts_schematic (default false) controls use
of schematic variables outside the context. Minor INCOMPATIBILITY,
declare rule_insts_schematic = true temporarily and update to use local
variable declarations or dummy patterns instead.

* Explicit instantiation via attributes "where", "of", and proof methods
"rule_tac" with derivatives like "subgoal_tac" etc. admit dummy patterns
("_") that stand for anonymous local variables.

* Generated schematic variables in standard format of exported facts are
incremented to avoid material in the proof context. Rare
INCOMPATIBILITY, explicit instantiation sometimes needs to refer to
different index.

* Lexical separation of signed and unsigned numerals: categories "num"
and "float" are unsigned. INCOMPATIBILITY: subtle change in precedence
of numeral signs, particularly in expressions involving infix syntax
like "(- 1) ^ n".

* Old inner token category "xnum" has been discontinued.  Potential
INCOMPATIBILITY for exotic syntax: may use mixfix grammar with "num"
token category instead.

*** HOL ***

* New (co)datatype package:
  - The 'datatype_new' command has been renamed 'datatype'. The old
    command of that name is now called 'old_datatype' and is provided
    by "~~/src/HOL/Library/Old_Datatype.thy". See
    'isabelle doc datatypes' for information on porting.
  - Renamed theorems:
      disc_corec ~> corec_disc
      disc_corec_iff ~> corec_disc_iff
      disc_exclude ~> distinct_disc
      disc_exhaust ~> exhaust_disc
      disc_map_iff ~> map_disc_iff
      sel_corec ~> corec_sel
      sel_exhaust ~> exhaust_sel
      sel_map ~> map_sel
      sel_set ~> set_sel
      sel_split ~> split_sel
      sel_split_asm ~> split_sel_asm
      strong_coinduct ~> coinduct_strong
      weak_case_cong ~> case_cong_weak
  - The "no_code" option to "free_constructors", "datatype_new", and
    "codatatype" has been renamed "plugins del: code".
  - The rules "set_empty" have been removed. They are easy
    consequences of other set rules "by auto".
  - The rule "set_cases" is now registered with the "[cases set]"
    attribute. This can influence the behavior of the "cases" proof
    method when more than one case rule is applicable (e.g., an
    assumption is of the form "w : set ws" and the method "cases w"
    is invoked). The solution is to specify the case rule explicitly
    (e.g. "cases w rule: widget.exhaust").
  - Renamed theories:
      BNF_Comp ~> BNF_Composition
      BNF_FP_Base ~> BNF_Fixpoint_Base
      BNF_GFP ~> BNF_Greatest_Fixpoint
      BNF_LFP ~> BNF_Least_Fixpoint
      BNF_Constructions_on_Wellorders ~> BNF_Wellorder_Constructions
      Cardinals/Constructions_on_Wellorders ~> Cardinals/Wellorder_Constructions
  - Lifting and Transfer setup for basic HOL types sum and prod (also
    option) is now performed by the BNF package. Theories Lifting_Sum,
    Lifting_Product and Lifting_Option from Main became obsolete and
    were removed. Changed definitions of the relators rel_prod and
    rel_sum (using inductive).
    INCOMPATIBILITY: use rel_prod.simps and rel_sum.simps instead
    of rel_prod_def and rel_sum_def.
    Minor INCOMPATIBILITY: (rarely used by name) transfer theorem names
    changed (e.g. map_prod_transfer ~> prod.map_transfer).
  - Parametricity theorems for map functions, relators, set functions,
    constructors, case combinators, discriminators, selectors and
    (co)recursors are automatically proved and registered as transfer

* Old datatype package:
  - The old 'datatype' command has been renamed 'old_datatype', and
    'rep_datatype' has been renamed 'old_rep_datatype'. They are
    provided by "~~/src/HOL/Library/Old_Datatype.thy". See
    'isabelle doc datatypes' for information on porting.
  - Renamed theorems:
      weak_case_cong ~> case_cong_weak
  - Renamed theory:
      ~~/src/HOL/Datatype.thy ~> ~~/src/HOL/Library/Old_Datatype.thy

* Nitpick:
  - Fixed soundness bug related to the strict and non-strict subset

* Sledgehammer:
  - CVC4 is now included with Isabelle instead of CVC3 and run by
  - Z3 is now always enabled by default, now that it is fully open
    source. The "z3_non_commercial" option is discontinued.
  - Minimization is now always enabled by default.
    Removed sub-command:
  - Proof reconstruction, both one-liners and Isar, has been
    dramatically improved.
  - Improved support for CVC4 and veriT.

* Old and new SMT modules:
  - The old 'smt' method has been renamed 'old_smt' and moved to
    'src/HOL/Library/Old_SMT.thy'. It is provided for compatibility,
    until applications have been ported to use the new 'smt' method. For
    the method to work, an older version of Z3 (e.g. Z3 3.2 or 4.0) must
    be installed, and the environment variable "OLD_Z3_SOLVER" must
    point to it.
  - The 'smt2' method has been renamed 'smt'.
  - New option 'smt_reconstruction_step_timeout' to limit the
    reconstruction time of Z3 proof steps in the new 'smt' method.
  - New option 'smt_statistics' to display statistics of the new 'smt'
    method, especially runtime statistics of Z3 proof reconstruction.

* Lifting: command 'lift_definition' allows to execute lifted constants
that have as a return type a datatype containing a subtype. This
overcomes long-time limitations in the area of code generation and
lifting, and avoids tedious workarounds.

* Command and antiquotation "value" provide different evaluation slots
(again), where the previous strategy (NBE after ML) serves as default.

* Add NO_MATCH-simproc, allows to check for syntactic non-equality.

* field_simps: Use NO_MATCH-simproc for distribution rules, to avoid
non-termination in case of distributing a division. With this change
field_simps is in some cases slightly less powerful, if it fails try to
add algebra_simps, or use divide_simps. Minor INCOMPATIBILITY.

* Separate class no_zero_divisors has been given up in favour of fully
algebraic semiring_no_zero_divisors. INCOMPATIBILITY.

* Class linordered_semidom really requires no zero divisors.

* Classes division_ring, field and linordered_field always demand
"inverse 0 = 0". Given up separate classes division_ring_inverse_zero,
field_inverse_zero and linordered_field_inverse_zero. INCOMPATIBILITY.

* Classes cancel_ab_semigroup_add / cancel_monoid_add specify explicit
additive inverse operation. INCOMPATIBILITY.

* Complex powers and square roots. The functions "ln" and "powr" are now
overloaded for types real and complex, and 0 powr y = 0 by definition.
INCOMPATIBILITY: type constraints may be necessary.

* The functions "sin" and "cos" are now defined for any type of sort
"{real_normed_algebra_1,banach}" type, so in particular on "real" and
"complex" uniformly. Minor INCOMPATIBILITY: type constraints may be

* New library of properties of the complex transcendental functions sin,
cos, tan, exp, Ln, Arctan, Arcsin, Arccos. Ported from HOL Light.

* The factorial function, "fact", now has type "nat => 'a" (of a sort
that admits numeric types including nat, int, real and complex.
INCOMPATIBILITY: an expression such as "fact 3 = 6" may require a type
constraint, and the combination "real (fact k)" is likely to be
unsatisfactory. If a type conversion is still necessary, then use
"of_nat (fact k)" or "real_of_nat (fact k)".

* Removed functions "natfloor" and "natceiling", use "nat o floor" and
"nat o ceiling" instead. A few of the lemmas have been retained and
adapted: in their names "natfloor"/"natceiling" has been replaced by

* Qualified some duplicated fact names required for boostrapping the
type class hierarchy:
  ab_add_uminus_conv_diff ~> diff_conv_add_uminus
  field_inverse_zero ~> inverse_zero
  field_divide_inverse ~> divide_inverse
  field_inverse ~> left_inverse

* Eliminated fact duplicates:
  mult_less_imp_less_right ~> mult_right_less_imp_less
  mult_less_imp_less_left ~> mult_left_less_imp_less

* Fact consolidation: even_less_0_iff is subsumed by
double_add_less_zero_iff_single_add_less_zero (simp by default anyway).

* Generalized and consolidated some theorems concerning divsibility:
  dvd_reduce ~> dvd_add_triv_right_iff
  dvd_plus_eq_right ~> dvd_add_right_iff
  dvd_plus_eq_left ~> dvd_add_left_iff

* "even" and "odd" are mere abbreviations for "2 dvd _" and "~ 2 dvd _"
and part of theory Main.
  even_def ~> even_iff_mod_2_eq_zero

* Lemma name consolidation: divide_Numeral1 ~> divide_numeral_1. Minor

* Bootstrap of listsum as special case of abstract product over lists.
Fact rename:
    listsum_def ~> listsum.eq_foldr

* Product over lists via constant "listprod".

* Theory List: renamed drop_Suc_conv_tl and nth_drop' to

* New infrastructure for compiling, running, evaluating and testing
generated code in target languages in HOL/Library/Code_Test. See
HOL/Codegenerator_Test/Code_Test* for examples.

* Library/Multiset:
  - Introduced "replicate_mset" operation.
  - Introduced alternative characterizations of the multiset ordering in
  - Renamed multiset ordering:
      <# ~> #<#
      <=# ~> #<=#
      \<subset># ~> #\<subset>#
      \<subseteq># ~> #\<subseteq>#
  - Introduced abbreviations for ill-named multiset operations:
      <#, \<subset># abbreviate < (strict subset)
      <=#, \<le>#, \<subseteq># abbreviate <= (subset or equal)
  - Renamed
      in_multiset_of ~> in_multiset_in_set
      Multiset.fold ~> fold_mset
      Multiset.filter ~> filter_mset
  - Removed mcard, is equal to size.
  - Added attributes: [simp]
      image_mset_id [simp]
      elem_multiset_of_set [simp, intro]
      comp_fun_commute_plus_mset [simp]
      comp_fun_commute.fold_mset_insert [OF comp_fun_commute_plus_mset, simp]
      in_mset_fold_plus_iff [iff]
      set_of_Union_mset [simp]
      in_Union_mset_iff [iff]

* Library/Sum_of_Squares: simplified and improved "sos" method. Always
use local CSDP executable, which is much faster than the NEOS server.
The "sos_cert" functionality is invoked as "sos" with additional
argument. Minor INCOMPATIBILITY.

* HOL-Decision_Procs: New counterexample generator quickcheck
[approximation] for inequalities of transcendental functions. Uses
hardware floating point arithmetic to randomly discover potential
counterexamples. Counterexamples are certified with the "approximation"
method. See HOL/Decision_Procs/ex/Approximation_Quickcheck_Ex.thy for

* HOL-Probability: Reworked measurability prover
  - applies destructor rules repeatedly
  - removed application splitting (replaced by destructor rule)
  - added congruence rules to rewrite measure spaces under the sets

* New proof method "rewrite" (in theory ~~/src/HOL/Library/Rewrite) for
single-step rewriting with subterm selection based on patterns.

*** ML ***

* Subtle change of name space policy: undeclared entries are now
considered inaccessible, instead of accessible via the fully-qualified
internal name. This mainly affects Name_Space.intern (and derivatives),
which may produce an unexpected Long_Name.hidden prefix. Note that
contemporary applications use the strict Name_Space.check (and
derivatives) instead, which is not affected by the change. Potential
INCOMPATIBILITY in rare applications of Name_Space.intern.

* Subtle change of error semantics of Toplevel.proof_of: regular user
ERROR instead of internal Toplevel.UNDEF.

* Basic combinators map, fold, fold_map, split_list, apply are available
as parameterized antiquotations, e.g. @{map 4} for lists of quadruples.

* Renamed "pairself" to "apply2", in accordance to @{apply 2}.

* Former combinators NAMED_CRITICAL and CRITICAL for central critical
sections have been discontinued, in favour of the more elementary
Multithreading.synchronized and its high-level derivative
Synchronized.var (which is usually sufficient in applications). Subtle
INCOMPATIBILITY: synchronized access needs to be atomic and cannot be

* Synchronized.value (ML) is actually synchronized (as in Scala): subtle
change of semantics with minimal potential for INCOMPATIBILITY.

* The main operations to certify logical entities are Thm.ctyp_of and
Thm.cterm_of with a local context; old-style global theory variants are
available as Thm.global_ctyp_of and Thm.global_cterm_of.

* Elementary operations in module Thm are no longer pervasive.
INCOMPATIBILITY, need to use qualified Thm.prop_of, Thm.cterm_of,
Thm.term_of etc.

* Proper context for various elementary tactics: assume_tac,
resolve_tac, eresolve_tac, dresolve_tac, forward_tac, match_tac,
compose_tac, Splitter.split_tac etc. INCOMPATIBILITY.

* Tactical PARALLEL_ALLGOALS is the most common way to refer to

* Goal.prove_multi is superseded by the fully general Goal.prove_common,
which also allows to specify a fork priority.

* Antiquotation @{command_spec "COMMAND"} is superseded by
@{command_keyword COMMAND} (usually without quotes and with PIDE

* Cartouches within ML sources are turned into values of type
Input.source (with formal position information).

*** System ***

* The Isabelle tool "update_cartouches" changes theory files to use
cartouches instead of old-style {* verbatim *} or `alt_string` tokens.

* The Isabelle tool "build" provides new options -X, -k, -x.

* Discontinued old-fashioned "codegen" tool. Code generation can always
be externally triggered using an appropriate ROOT file plus a
corresponding theory. Parametrization is possible using environment
variables, or ML snippets in the most extreme cases. Minor

* JVM system property "isabelle.threads" determines size of Scala thread
pool, like Isabelle system option "threads" for ML.

* JVM system property "isabelle.laf" determines the default Swing
look-and-feel, via internal class name or symbolic name as in the jEdit
menu Global Options / Appearance.

* Support for Proof General and Isar TTY loop has been discontinued.
Minor INCOMPATIBILITY, use standard PIDE infrastructure instead.

New in Isabelle2014 (August 2014)

*** General ***

* Support for official Standard ML within the Isabelle context.
Command 'SML_file' reads and evaluates the given Standard ML file.
Toplevel bindings are stored within the theory context; the initial
environment is restricted to the Standard ML implementation of
Poly/ML, without the add-ons of Isabelle/ML.  Commands 'SML_import'
and 'SML_export' allow to exchange toplevel bindings between the two
separate environments.  See also ~~/src/Tools/SML/Examples.thy for
some examples.

* Standard tactics and proof methods such as "clarsimp", "auto" and
"safe" now preserve equality hypotheses "x = expr" where x is a free
variable.  Locale assumptions and chained facts containing "x"
continue to be useful.  The new method "hypsubst_thin" and the
configuration option "hypsubst_thin" (within the attribute name space)
restore the previous behavior.  INCOMPATIBILITY, especially where
induction is done after these methods or when the names of free and
bound variables clash.  As first approximation, old proofs may be
repaired by "using [[hypsubst_thin = true]]" in the critical spot.

* More static checking of proof methods, which allows the system to
form a closure over the concrete syntax.  Method arguments should be
processed in the original proof context as far as possible, before
operating on the goal state.  In any case, the standard discipline for
subgoal-addressing needs to be observed: no subgoals or a subgoal
number that is out of range produces an empty result sequence, not an
exception.  Potential INCOMPATIBILITY for non-conformant tactical
proof tools.

* Lexical syntax (inner and outer) supports text cartouches with
arbitrary nesting, and without escapes of quotes etc.  The Prover IDE
supports input via ` (backquote).

* The outer syntax categories "text" (for formal comments and document
markup commands) and "altstring" (for literal fact references) allow
cartouches as well, in addition to the traditional mix of quotations.

* Syntax of document antiquotation @{rail} now uses \<newline> instead
of "\\", to avoid the optical illusion of escaped backslash within
string token.  General renovation of its syntax using text cartouches.

* Discontinued legacy_isub_isup, which was a temporary workaround for
Isabelle/ML in Isabelle2013-1.  The prover process no longer accepts
old identifier syntax with \<^isub> or \<^isup>.  Potential

* Document antiquotation @{url} produces markup for the given URL,
which results in an active hyperlink within the text.

* Document antiquotation @{file_unchecked} is like @{file}, but does
not check existence within the file-system.

* Updated and extended manuals: codegen, datatypes, implementation,
isar-ref, jedit, system.

*** Prover IDE -- Isabelle/Scala/jEdit ***

* Improved Document panel: simplified interaction where every single
mouse click (re)opens document via desktop environment or as jEdit

* Support for Navigator plugin (with toolbar buttons), with connection
to PIDE hyperlinks.

* Auxiliary files ('ML_file' etc.) are managed by the Prover IDE.
Open text buffers take precedence over copies within the file-system.

* Improved support for Isabelle/ML, with jEdit mode "isabelle-ml" for
auxiliary ML files.

* Improved syntactic and semantic completion mechanism, with simple
templates, completion language context, name-space completion,
file-name completion, spell-checker completion.

* Refined GUI popup for completion: more robust key/mouse event
handling and propagation to enclosing text area -- avoid loosing
keystrokes with slow / remote graphics displays.

* Completion popup supports both ENTER and TAB (default) to select an
item, depending on Isabelle options.

* Refined insertion of completion items wrt. jEdit text: multiple
selections, rectangular selections, rectangular selection as "tall

* Integrated spell-checker for document text, comments etc. with
completion popup and context-menu.

* More general "Query" panel supersedes "Find" panel, with GUI access
to commands 'find_theorems' and 'find_consts', as well as print
operations for the context.  Minor incompatibility in keyboard
shortcuts etc.: replace action isabelle-find by isabelle-query.

* Search field for all output panels ("Output", "Query", "Info" etc.)
to highlight text via regular expression.

* Option "jedit_print_mode" (see also "Plugin Options / Isabelle /
General") allows to specify additional print modes for the prover
process, without requiring old-fashioned command-line invocation of
"isabelle jedit -m MODE".

* More support for remote files (e.g. http) using standard Java
networking operations instead of jEdit virtual file-systems.

* Empty editors buffers that are no longer required (e.g.\ via theory
imports) are automatically removed from the document model.

* Improved monitor panel.

* Improved Console/Scala plugin: more uniform scala.Console output,
more robust treatment of threads and interrupts.

* Improved management of dockable windows: clarified keyboard focus
and window placement wrt. main editor view; optional menu item to
"Detach" a copy where this makes sense.

* New Simplifier Trace panel provides an interactive view of the
simplification process, enabled by the "simp_trace_new" attribute
within the context.

*** Pure ***

* Low-level type-class commands 'classes', 'classrel', 'arities' have
been discontinued to avoid the danger of non-trivial axiomatization
that is not immediately visible.  INCOMPATIBILITY, use regular
'instance' command with proof.  The required OFCLASS(...) theorem
might be postulated via 'axiomatization' beforehand, or the proof
finished trivially if the underlying class definition is made vacuous
(without any assumptions).  See also Isabelle/ML operations
Axclass.class_axiomatization, Axclass.classrel_axiomatization,

* Basic constants of Pure use more conventional names and are always
qualified.  Rare INCOMPATIBILITY, but with potentially serious
consequences, notably for tools in Isabelle/ML.  The following
renaming needs to be applied:

  ==             ~>  Pure.eq
  ==>            ~>  Pure.imp
  all            ~>  Pure.all
  TYPE           ~>  Pure.type
  dummy_pattern  ~>  Pure.dummy_pattern

Systematic porting works by using the following theory setup on a
*previous* Isabelle version to introduce the new name accesses for the
old constants:

setup {*
  fn thy => thy
    |> Sign.root_path
    |> Sign.const_alias (Binding.qualify true "Pure" @{binding eq}) "=="
    |> Sign.const_alias (Binding.qualify true "Pure" @{binding imp}) "==>"
    |> Sign.const_alias (Binding.qualify true "Pure" @{binding all}) "all"
    |> Sign.restore_naming thy

Thus ML antiquotations like @{const_name Pure.eq} may be used already.
Later the application is moved to the current Isabelle version, and
the auxiliary aliases are deleted.

* Attributes "where" and "of" allow an optional context of local
variables ('for' declaration): these variables become schematic in the
instantiated theorem.

* Obsolete attribute "standard" has been discontinued (legacy since
Isabelle2012).  Potential INCOMPATIBILITY, use explicit 'for' context
where instantiations with schematic variables are intended (for
declaration commands like 'lemmas' or attributes like "of").  The
following temporary definition may help to port old applications:

  attribute_setup standard =
    "Scan.succeed (Thm.rule_attribute (K Drule.export_without_context))"

* More thorough check of proof context for goal statements and
attributed fact expressions (concerning background theory, declared
hyps).  Potential INCOMPATIBILITY, tools need to observe standard
context discipline.  See also Assumption.add_assumes and the more
primitive Thm.assume_hyps.

* Inner syntax token language allows regular quoted strings "..."
(only makes sense in practice, if outer syntax is delimited
differently, e.g. via cartouches).

* Command 'print_term_bindings' supersedes 'print_binds' for clarity,
but the latter is retained some time as Proof General legacy.

* Code generator preprocessor: explicit control of simp tracing on a
per-constant basis.  See attribute "code_preproc".

*** HOL ***

* Code generator: enforce case of identifiers only for strict target
language requirements.  INCOMPATIBILITY.

* Code generator: explicit proof contexts in many ML interfaces.

* Code generator: minimize exported identifiers by default.  Minor

* Code generation for SML and OCaml: dropped arcane "no_signatures"

* "declare [[code abort: ...]]" replaces "code_abort ...".

* "declare [[code drop: ...]]" drops all code equations associated
with the given constants.

* Code generations are provided for make, fields, extend and truncate
operations on records.

* Command and antiquotation "value" are now hardcoded against nbe and

* Renamed command 'enriched_type' to 'functor'. INCOMPATIBILITY.

* The symbol "\<newline>" may be used within char or string literals
to represent (Char Nibble0 NibbleA), i.e. ASCII newline.

* Qualified String.implode and String.explode.  INCOMPATIBILITY.

* Simplifier: Enhanced solver of preconditions of rewrite rules can
now deal with conjunctions.  For help with converting proofs, the old
behaviour of the simplifier can be restored like this: declare/using
[[simp_legacy_precond]].  This configuration option will disappear
again in the future.  INCOMPATIBILITY.

* Simproc "finite_Collect" is no longer enabled by default, due to
spurious crashes and other surprises.  Potential INCOMPATIBILITY.

* Moved new (co)datatype package and its dependencies from session
  "HOL-BNF" to "HOL".  The commands 'bnf', 'wrap_free_constructors',
  'datatype_new', 'codatatype', 'primcorec', 'primcorecursive' are now
  part of theory "Main".

  Theory renamings:
    FunDef.thy ~> Fun_Def.thy (and Fun_Def_Base.thy)
    Library/Wfrec.thy ~> Wfrec.thy
    Library/Zorn.thy ~> Zorn.thy
    Cardinals/Order_Relation.thy ~> Order_Relation.thy
    Library/Order_Union.thy ~> Cardinals/Order_Union.thy
    Cardinals/Cardinal_Arithmetic_Base.thy ~> BNF_Cardinal_Arithmetic.thy
    Cardinals/Cardinal_Order_Relation_Base.thy ~> BNF_Cardinal_Order_Relation.thy
    Cardinals/Constructions_on_Wellorders_Base.thy ~> BNF_Constructions_on_Wellorders.thy
    Cardinals/Wellorder_Embedding_Base.thy ~> BNF_Wellorder_Embedding.thy
    Cardinals/Wellorder_Relation_Base.thy ~> BNF_Wellorder_Relation.thy
    BNF/Ctr_Sugar.thy ~> Ctr_Sugar.thy
    BNF/Basic_BNFs.thy ~> Basic_BNFs.thy
    BNF/BNF_Comp.thy ~> BNF_Comp.thy
    BNF/BNF_Def.thy ~> BNF_Def.thy
    BNF/BNF_FP_Base.thy ~> BNF_FP_Base.thy
    BNF/BNF_GFP.thy ~> BNF_GFP.thy
    BNF/BNF_LFP.thy ~> BNF_LFP.thy
    BNF/BNF_Util.thy ~> BNF_Util.thy
    BNF/Coinduction.thy ~> Coinduction.thy
    BNF/More_BNFs.thy ~> Library/More_BNFs.thy
    BNF/Countable_Type.thy ~> Library/Countable_Set_Type.thy
    BNF/Examples/* ~> BNF_Examples/*

  New theories:
    Wellorder_Extension.thy (split from Zorn.thy)

  Discontinued theories:


* New (co)datatype package:
  - Command 'primcorec' is fully implemented.
  - Command 'datatype_new' generates size functions ("size_xxx" and
    "size") as required by 'fun'.
  - BNFs are integrated with the Lifting tool and new-style
    (co)datatypes with Transfer.
  - Renamed commands:
      datatype_new_compat ~> datatype_compat
      primrec_new ~> primrec
      wrap_free_constructors ~> free_constructors
  - The generated constants "xxx_case" and "xxx_rec" have been renamed
    "case_xxx" and "rec_xxx" (e.g., "prod_case" ~> "case_prod").
  - The constant "xxx_(un)fold" and related theorems are no longer
    generated.  Use "xxx_(co)rec" or define "xxx_(un)fold" manually
    using "prim(co)rec".
  - No discriminators are generated for nullary constructors by
    default, eliminating the need for the odd "=:" syntax.
  - No discriminators or selectors are generated by default by
    "datatype_new", unless custom names are specified or the new
    "discs_sels" option is passed.

* Old datatype package:
  - The generated theorems "xxx.cases" and "xxx.recs" have been
    renamed "" and "xxx.rec" (e.g., "sum.cases" ->
  - The generated constants "xxx_case", "xxx_rec", and "xxx_size" have
    been renamed "case_xxx", "rec_xxx", and "size_xxx" (e.g.,
    "prod_case" ~> "case_prod").  INCOMPATIBILITY.

* The types "'a list" and "'a option", their set and map functions,
  their relators, and their selectors are now produced using the new
  BNF-based datatype package.

  Renamed constants:
    Option.set ~> set_option ~> map_option
    option_rel ~> rel_option

  Renamed theorems:
    set_def ~> set_rec[abs_def]
    map_def ~> map_rec[abs_def]
    Option.map_def ~> map_option_case[abs_def] (with "case_option" instead of "rec_option")
    option.recs ~> option.rec
    list_all2_def ~> list_all2_iff
    set.simps ~> set_simps (or the slightly different "list.set")
    map.simps ~>
    hd.simps ~> list.sel(1)
    tl.simps ~> list.sel(2-3)
    the.simps ~> option.sel


* The following map functions and relators have been renamed:
    sum_map ~> map_sum
    map_pair ~> map_prod
    prod_rel ~> rel_prod
    sum_rel ~> rel_sum
    fun_rel ~> rel_fun
    set_rel ~> rel_set
    filter_rel ~> rel_filter
    fset_rel ~> rel_fset (in "src/HOL/Library/FSet.thy")
    cset_rel ~> rel_cset (in "src/HOL/Library/Countable_Set_Type.thy")
    vset ~> rel_vset (in "src/HOL/Library/Quotient_Set.thy")


* Lifting and Transfer:
  - a type variable as a raw type is supported
  - stronger reflexivity prover
  - rep_eq is always generated by lift_definition
  - setup for Lifting/Transfer is now automated for BNFs
    + holds for BNFs that do not contain a dead variable
    + relator_eq, relator_mono, relator_distr, relator_domain,
      relator_eq_onp, quot_map, transfer rules for bi_unique, bi_total,
      right_unique, right_total, left_unique, left_total are proved
    + definition of a predicator is generated automatically
    + simplification rules for a predicator definition are proved
      automatically for datatypes
  - consolidation of the setup of Lifting/Transfer
    + property that a relator preservers reflexivity is not needed any
    + left_total and left_unique rules are now transfer rules
      (reflexivity_rule attribute not needed anymore)
    + Domainp does not have to be a separate assumption in
      relator_domain theorems (=> more natural statement)
  - registration of code equations is more robust
  - respectfulness proof obligation is preprocessed to a more readable
  - eq_onp is always unfolded in respectfulness proof obligation
  - unregister lifting setup for Code_Numeral.integer and
  - Lifting.invariant -> eq_onp

* New internal SAT solver "cdclite" that produces models and proof
traces.  This solver replaces the internal SAT solvers "enumerate" and
"dpll".  Applications that explicitly used one of these two SAT
solvers should use "cdclite" instead. In addition, "cdclite" is now
the default SAT solver for the "sat" and "satx" proof methods and
corresponding tactics; the old default can be restored using "declare
[[sat_solver = zchaff_with_proofs]]".  Minor INCOMPATIBILITY.

* SMT module: A new version of the SMT module, temporarily called
"SMT2", uses SMT-LIB 2 and supports recent versions of Z3 (e.g.,
4.3). The new proof method is called "smt2". CVC3 and CVC4 are also
supported as oracles. Yices is no longer supported, because no version
of the solver can handle both SMT-LIB 2 and quantifiers.

* Activation of Z3 now works via "z3_non_commercial" system option
(without requiring restart), instead of former settings variable
"Z3_NON_COMMERCIAL".  The option can be edited in Isabelle/jEdit menu
Plugin Options / Isabelle / General.

* Sledgehammer:
  - Z3 can now produce Isar proofs.
  - MaSh overhaul:
    . New SML-based learning algorithms eliminate the dependency on
      Python and increase performance and reliability.
    . MaSh and MeSh are now used by default together with the
      traditional MePo (Meng-Paulson) relevance filter. To disable
      MaSh, set the "MaSh" system option in Isabelle/jEdit Plugin
      Options / Isabelle / General to "none".
  - New option:
  - Renamed options:
      isar_compress ~> compress
      isar_try0 ~> try0


* Removed solvers remote_cvc3 and remote_z3. Use cvc3 and z3 instead.

* Nitpick:
  - Fixed soundness bug whereby mutually recursive datatypes could
    take infinite values.
  - Fixed soundness bug with low-level number functions such as
    "Abs_Integ" and "Rep_Integ".
  - Removed "std" option.
  - Renamed "show_datatypes" to "show_types" and "hide_datatypes" to

* Metis: Removed legacy proof method 'metisFT'. Use 'metis
(full_types)' instead. INCOMPATIBILITY.

* Try0: Added 'algebra' and 'meson' to the set of proof methods.

* Adjustion of INF and SUP operations:
  - Elongated constants INFI and SUPR to INFIMUM and SUPREMUM.
  - Consolidated theorem names containing INFI and SUPR: have INF and
    SUP instead uniformly.
  - More aggressive normalization of expressions involving INF and Inf
    or SUP and Sup.
  - INF_image and SUP_image do not unfold composition.
  - Dropped facts INF_comp, SUP_comp.
  - Default congruence rules strong_INF_cong and strong_SUP_cong, with
    simplifier implication in premises.  Generalize and replace former
    INT_cong, SUP_cong


* SUP and INF generalized to conditionally_complete_lattice.

* Swapped orientation of facts image_comp and vimage_comp:

  image_compose ~> image_comp [symmetric]
  image_comp ~> image_comp [symmetric]
  vimage_compose ~> vimage_comp [symmetric]
  vimage_comp ~> vimage_comp [symmetric]


* Theory reorganization: split of Big_Operators.thy into
Groups_Big.thy and Lattices_Big.thy.

* Consolidated some facts about big group operators:

    setsum_0' ~> setsum.neutral
    setsum_0 ~> setsum.neutral_const
    setsum_addf ~> setsum.distrib
    setsum_cartesian_product ~> setsum.cartesian_product
    setsum_cases ~> setsum.If_cases
    setsum_commute ~> setsum.commute
    setsum_cong ~> setsum.cong
    setsum_delta ~>
    setsum_delta' ~>'
    setsum_diff1' ~> setsum.remove
    setsum_empty ~> setsum.empty
    setsum_infinite ~> setsum.infinite
    setsum_insert ~> setsum.insert
    setsum_inter_restrict'' ~> setsum.inter_filter
    setsum_mono_zero_cong_left ~> setsum.mono_neutral_cong_left
    setsum_mono_zero_cong_right ~> setsum.mono_neutral_cong_right
    setsum_mono_zero_left ~> setsum.mono_neutral_left
    setsum_mono_zero_right ~> setsum.mono_neutral_right
    setsum_reindex ~> setsum.reindex
    setsum_reindex_cong ~> setsum.reindex_cong
    setsum_reindex_nonzero ~> setsum.reindex_nontrivial
    setsum_restrict_set ~> setsum.inter_restrict
    setsum_Plus ~> setsum.Plus
    setsum_setsum_restrict ~> setsum.commute_restrict
    setsum_Sigma ~> setsum.Sigma
    setsum_subset_diff ~> setsum.subset_diff
    setsum_Un_disjoint ~> setsum.union_disjoint
    setsum_UN_disjoint ~> setsum.UNION_disjoint
    setsum_Un_Int ~> setsum.union_inter
    setsum_Union_disjoint ~> setsum.Union_disjoint
    setsum_UNION_zero ~> setsum.Union_comp
    setsum_Un_zero ~> setsum.union_inter_neutral
    strong_setprod_cong ~> setprod.strong_cong
    strong_setsum_cong ~> setsum.strong_cong
    setprod_1' ~> setprod.neutral
    setprod_1 ~> setprod.neutral_const
    setprod_cartesian_product ~> setprod.cartesian_product
    setprod_cong ~> setprod.cong
    setprod_delta ~>
    setprod_delta' ~>'
    setprod_empty ~> setprod.empty
    setprod_infinite ~> setprod.infinite
    setprod_insert ~> setprod.insert
    setprod_mono_one_cong_left ~> setprod.mono_neutral_cong_left
    setprod_mono_one_cong_right ~> setprod.mono_neutral_cong_right
    setprod_mono_one_left ~> setprod.mono_neutral_left
    setprod_mono_one_right ~> setprod.mono_neutral_right
    setprod_reindex ~> setprod.reindex
    setprod_reindex_cong ~> setprod.reindex_cong
    setprod_reindex_nonzero ~> setprod.reindex_nontrivial
    setprod_Sigma ~> setprod.Sigma
    setprod_subset_diff ~> setprod.subset_diff
    setprod_timesf ~> setprod.distrib
    setprod_Un2 ~> setprod.union_diff2
    setprod_Un_disjoint ~> setprod.union_disjoint
    setprod_UN_disjoint ~> setprod.UNION_disjoint
    setprod_Un_Int ~> setprod.union_inter
    setprod_Union_disjoint ~> setprod.Union_disjoint
    setprod_Un_one ~> setprod.union_inter_neutral

  Dropped setsum_cong2 (simple variant of setsum.cong).
  Dropped setsum_inter_restrict' (simple variant of setsum.inter_restrict)
  Dropped setsum_reindex_id, setprod_reindex_id
    (simple variants of setsum.reindex [symmetric], setprod.reindex [symmetric]).


* Abolished slightly odd global lattice interpretation for min/max.

  Fact consolidations:
    min_max.inf_assoc ~> min.assoc
    min_max.inf_commute ~> min.commute
    min_max.inf_left_commute ~> min.left_commute
    min_max.inf_idem ~> min.idem
    min_max.inf_left_idem ~> min.left_idem
    min_max.inf_right_idem ~> min.right_idem
    min_max.sup_assoc ~> max.assoc
    min_max.sup_commute ~> max.commute
    min_max.sup_left_commute ~> max.left_commute
    min_max.sup_idem ~> max.idem
    min_max.sup_left_idem ~> max.left_idem
    min_max.sup_inf_distrib1 ~> max_min_distrib2
    min_max.sup_inf_distrib2 ~> max_min_distrib1
    min_max.inf_sup_distrib1 ~> min_max_distrib2
    min_max.inf_sup_distrib2 ~> min_max_distrib1
    min_max.distrib ~> min_max_distribs
    min_max.inf_absorb1 ~> min.absorb1
    min_max.inf_absorb2 ~> min.absorb2
    min_max.sup_absorb1 ~> max.absorb1
    min_max.sup_absorb2 ~> max.absorb2
    min_max.le_iff_inf ~> min.absorb_iff1
    min_max.le_iff_sup ~> max.absorb_iff2
    min_max.inf_le1 ~> min.cobounded1
    min_max.inf_le2 ~> min.cobounded2
    le_maxI1, min_max.sup_ge1 ~> max.cobounded1
    le_maxI2, min_max.sup_ge2 ~> max.cobounded2
    min_max.le_infI1 ~> min.coboundedI1
    min_max.le_infI2 ~> min.coboundedI2
    min_max.le_supI1 ~> max.coboundedI1
    min_max.le_supI2 ~> max.coboundedI2
    min_max.less_infI1 ~> min.strict_coboundedI1
    min_max.less_infI2 ~> min.strict_coboundedI2
    min_max.less_supI1 ~> max.strict_coboundedI1
    min_max.less_supI2 ~> max.strict_coboundedI2
    min_max.inf_mono ~> min.mono
    min_max.sup_mono ~> max.mono
    min_max.le_infI, min_max.inf_greatest ~> min.boundedI
    min_max.le_supI, min_max.sup_least ~> max.boundedI
    min_max.le_inf_iff ~> min.bounded_iff
    min_max.le_sup_iff ~> max.bounded_iff

For min_max.inf_sup_aci, prefer (one of) min.commute, min.assoc,
min.left_commute, min.left_idem, max.commute, max.assoc,
max.left_commute, max.left_idem directly.

For min_max.inf_sup_ord, prefer (one of) min.cobounded1,
min.cobounded2, max.cobounded1m max.cobounded2 directly.

For min_ac or max_ac, prefer more general collection ac_simps.


* Theorem disambiguation Inf_le_Sup (on finite sets) ~>
Inf_fin_le_Sup_fin.  INCOMPATIBILITY.

* Qualified constant names Wellfounded.acc, Wellfounded.accp.

* Fact generalization and consolidation:
    neq_one_mod_two, mod_2_not_eq_zero_eq_one_int ~> not_mod_2_eq_0_eq_1


* Purely algebraic definition of even.  Fact generalization and
    nat_even_iff_2_dvd, int_even_iff_2_dvd ~> even_iff_2_dvd
    even_zero_(nat|int) ~> even_zero


* Abolished neg_numeral.
  - Canonical representation for minus one is "- 1".
  - Canonical representation for other negative numbers is "- (numeral _)".
  - When devising rule sets for number calculation, consider the
    following canonical cases: 0, 1, numeral _, - 1, - numeral _.
  - HOLogic.dest_number also recognizes numerals in non-canonical forms
    like "numeral One", "- numeral One", "- 0" and even "- ... - _".
  - Syntax for negative numerals is mere input syntax.


* Reduced name variants for rules on associativity and commutativity:

    add_assoc ~> add.assoc
    add_commute ~> add.commute
    add_left_commute ~> add.left_commute
    mult_assoc ~> mult.assoc
    mult_commute ~> mult.commute
    mult_left_commute ~> mult.left_commute
    nat_add_assoc ~> add.assoc
    nat_add_commute ~> add.commute
    nat_add_left_commute ~> add.left_commute
    nat_mult_assoc ~> mult.assoc
    nat_mult_commute ~> mult.commute
    eq_assoc ~> iff_assoc
    eq_left_commute ~> iff_left_commute


* Fact collections add_ac and mult_ac are considered old-fashioned.
Prefer ac_simps instead, or specify rules
(add|mult).(assoc|commute|left_commute) individually.

* Elimination of fact duplicates:
    equals_zero_I ~> minus_unique
    diff_eq_0_iff_eq ~> right_minus_eq
    nat_infinite ~> infinite_UNIV_nat
    int_infinite ~> infinite_UNIV_int


* Fact name consolidation:
    diff_def, diff_minus, ab_diff_minus ~> diff_conv_add_uminus
    minus_le_self_iff ~> neg_less_eq_nonneg
    le_minus_self_iff ~> less_eq_neg_nonpos
    neg_less_nonneg ~> neg_less_pos
    less_minus_self_iff ~> less_neg_neg [simp]


* More simplification rules on unary and binary minus:
add_diff_cancel, add_diff_cancel_left, add_le_same_cancel1,
add_le_same_cancel2, add_less_same_cancel1, add_less_same_cancel2,
add_minus_cancel, diff_add_cancel, le_add_same_cancel1,
le_add_same_cancel2, less_add_same_cancel1, less_add_same_cancel2,
minus_add_cancel, uminus_add_conv_diff.  These correspondingly have
been taken away from fact collections algebra_simps and field_simps.

To restore proofs, the following patterns are helpful:

a) Arbitrary failing proof not involving "diff_def":
Consider simplification with algebra_simps or field_simps.

b) Lifting rules from addition to subtraction:
Try with "using <rule for addition> of [... "- _" ...]" by simp".

c) Simplification with "diff_def": just drop "diff_def".
Consider simplification with algebra_simps or field_simps;
or the brute way with
"simp add: diff_conv_add_uminus del: add_uminus_conv_diff".

* Introduce bdd_above and bdd_below in theory
Conditionally_Complete_Lattices, use them instead of explicitly
stating boundedness of sets.

* ccpo.admissible quantifies only over non-empty chains to allow more
syntax-directed proof rules; the case of the empty chain shows up as
additional case in fixpoint induction proofs.  INCOMPATIBILITY.

* Removed and renamed theorems in Series:
  summable_le         ~>  suminf_le
  suminf_le           ~>  suminf_le_const
  series_pos_le       ~>  setsum_le_suminf
  series_pos_less     ~>  setsum_less_suminf
  suminf_ge_zero      ~>  suminf_nonneg
  suminf_gt_zero      ~>  suminf_pos
  suminf_gt_zero_iff  ~>  suminf_pos_iff
  summable_sumr_LIMSEQ_suminf  ~>  summable_LIMSEQ
  suminf_0_le         ~>  suminf_nonneg [rotate]
  pos_summable        ~>  summableI_nonneg_bounded
  ratio_test          ~>  summable_ratio_test

  removed series_zero, replaced by sums_finite

  removed auxiliary lemmas:

    sumr_offset, sumr_offset2, sumr_offset3, sumr_offset4, sumr_group,
    half, le_Suc_ex_iff, lemma_realpow_diff_sumr,
    real_setsum_nat_ivl_bounded, summable_le2, ratio_test_lemma2,
    sumr_minus_one_realpow_zerom, sumr_one_lb_realpow_zero,
    summable_convergent_sumr_iff, sumr_diff_mult_const


* Replace (F)DERIV syntax by has_derivative:
  - "(f has_derivative f') (at x within s)" replaces "FDERIV f x : s : f'"

  - "(f has_field_derivative f') (at x within s)" replaces "DERIV f x : s : f'"

  - "f differentiable at x within s" replaces "_ differentiable _ in _" syntax

  - removed constant isDiff

  - "DERIV f x : f'" and "FDERIV f x : f'" syntax is only available as
    input syntax.

  - "DERIV f x : s : f'" and "FDERIV f x : s : f'" syntax removed.

  - Renamed FDERIV_... lemmas to has_derivative_...

  - renamed deriv (the syntax constant used for "DERIV _ _ :> _") to DERIV

  - removed DERIV_intros, has_derivative_eq_intros

  - introduced derivative_intros and deriative_eq_intros which
    includes now rules for DERIV, has_derivative and

  - Other renamings:
    differentiable_def        ~>  real_differentiable_def
    differentiableE           ~>  real_differentiableE
    fderiv_def                ~>  has_derivative_at
    field_fderiv_def          ~>  field_has_derivative_at
    isDiff_der                ~>  differentiable_def
    deriv_fderiv              ~>  has_field_derivative_def
    deriv_def                 ~>  DERIV_def


* Include more theorems in continuous_intros. Remove the
continuous_on_intros, isCont_intros collections, these facts are now
in continuous_intros.

* Theorems about complex numbers are now stated only using Re and Im,
the Complex constructor is not used anymore. It is possible to use
primcorec to defined the behaviour of a complex-valued function.

Removed theorems about the Complex constructor from the simpset, they
are available as the lemma collection legacy_Complex_simps. This
especially removes

    i_complex_of_real: "ii * complex_of_real r = Complex 0 r".

Instead the reverse direction is supported with
    Complex_eq: "Complex a b = a + \<i> * b"

Moved csqrt from Fundamental_Algebra_Theorem to Complex.

    Re/Im                  ~>  complex.sel
    complex_Re/Im_zero     ~>  zero_complex.sel
    complex_Re/Im_add      ~>  plus_complex.sel
    complex_Re/Im_minus    ~>  uminus_complex.sel
    complex_Re/Im_diff     ~>  minus_complex.sel
    complex_Re/Im_one      ~>  one_complex.sel
    complex_Re/Im_mult     ~>  times_complex.sel
    complex_Re/Im_inverse  ~>  inverse_complex.sel
    complex_Re/Im_scaleR   ~>  scaleR_complex.sel
    complex_Re/Im_i        ~>  ii.sel
    complex_Re/Im_cnj      ~>  cnj.sel
    Re/Im_cis              ~>  cis.sel

    complex_divide_def   ~>  divide_complex_def
    complex_norm_def     ~>  norm_complex_def
    cmod_def             ~>  norm_complex_de

  Removed theorems:


* Theory Lubs moved HOL image to HOL-Library. It is replaced by
Conditionally_Complete_Lattices.  INCOMPATIBILITY.

* HOL-Library: new theory src/HOL/Library/Tree.thy.

* HOL-Library: removed theory src/HOL/Library/Kleene_Algebra.thy; it
is subsumed by session Kleene_Algebra in AFP.

* HOL-Library / theory RBT: various constants and facts are hidden;
lifting setup is unregistered.  INCOMPATIBILITY.

* HOL-Cardinals: new theory src/HOL/Cardinals/Ordinal_Arithmetic.thy.

* HOL-Word: bit representations prefer type bool over type bit.

* HOL-Word:
  - Abandoned fact collection "word_arith_alts", which is a duplicate
    of "word_arith_wis".
  - Dropped first (duplicated) element in fact collections
    "sint_word_ariths", "word_arith_alts", "uint_word_ariths",

* HOL-Number_Theory:
  - consolidated the proofs of the binomial theorem
  - the function fib is again of type nat => nat and not overloaded
  - no more references to Old_Number_Theory in the HOL libraries
    (except the AFP)


* HOL-Multivariate_Analysis:
  - Type class ordered_real_vector for ordered vector spaces.
  - New theory Complex_Basic_Analysis defining complex derivatives,
    holomorphic functions, etc., ported from HOL Light's
  - Changed order of ordered_euclidean_space to be compatible with
    pointwise ordering on products. Therefore instance of
    conditionally_complete_lattice and ordered_real_vector.
    INCOMPATIBILITY: use box instead of greaterThanLessThan or
    explicit set-comprehensions with eucl_less for other (half-)open
  - removed dependencies on type class ordered_euclidean_space with
    introduction of "cbox" on euclidean_space
    - renamed theorems:
        interval ~> box
        mem_interval ~> mem_box
        interval_eq_empty ~> box_eq_empty
        interval_ne_empty ~> box_ne_empty
        interval_sing(1) ~> cbox_sing
        interval_sing(2) ~> box_sing
        subset_interval_imp ~> subset_box_imp
        subset_interval ~> subset_box
        open_interval ~> open_box
        closed_interval ~> closed_cbox
        interior_closed_interval ~> interior_cbox
        bounded_closed_interval ~> bounded_cbox
        compact_interval ~> compact_cbox
        bounded_subset_closed_interval_symmetric ~> bounded_subset_cbox_symmetric
        bounded_subset_closed_interval ~> bounded_subset_cbox
        mem_interval_componentwiseI ~> mem_box_componentwiseI
        convex_box ~> convex_prod
        rel_interior_real_interval ~> rel_interior_real_box
        convex_interval ~> convex_box
        convex_hull_eq_real_interval ~> convex_hull_eq_real_cbox
        frechet_derivative_within_closed_interval ~> frechet_derivative_within_cbox
        content_closed_interval' ~> content_cbox'
        elementary_subset_interval ~> elementary_subset_box
        diameter_closed_interval ~> diameter_cbox
        frontier_closed_interval ~> frontier_cbox
        frontier_open_interval ~> frontier_box
        bounded_subset_open_interval_symmetric ~> bounded_subset_box_symmetric
        closure_open_interval ~> closure_box
        open_closed_interval_convex ~> open_cbox_convex
        open_interval_midpoint ~> box_midpoint
        content_image_affinity_interval ~> content_image_affinity_cbox
        is_interval_interval ~> is_interval_cbox + is_interval_box + is_interval_closed_interval
        bounded_interval ~> bounded_closed_interval + bounded_boxes

    - respective theorems for intervals over the reals:
        content_closed_interval + content_cbox
        has_integral + has_integral_real
        fine_division_exists + fine_division_exists_real
        has_integral_null + has_integral_null_real
        tagged_division_union_interval + tagged_division_union_interval_real
        has_integral_const + has_integral_const_real
        integral_const + integral_const_real
        has_integral_bound + has_integral_bound_real
        integrable_continuous + integrable_continuous_real
        integrable_subinterval + integrable_subinterval_real
        has_integral_reflect_lemma + has_integral_reflect_lemma_real
        integrable_reflect + integrable_reflect_real
        integral_reflect + integral_reflect_real
        image_affinity_interval + image_affinity_cbox
        image_smult_interval + image_smult_cbox
        integrable_const + integrable_const_ivl
        integrable_on_subinterval + integrable_on_subcbox

  - renamed theorems:
    derivative_linear         ~>  has_derivative_bounded_linear
    derivative_is_linear      ~>  has_derivative_linear
    bounded_linear_imp_linear ~>  bounded_linear.linear

* HOL-Probability:
  - Renamed positive_integral to nn_integral:

    . Renamed all lemmas "*positive_integral*" to *nn_integral*"
      positive_integral_positive ~> nn_integral_nonneg

    . Renamed abbreviation integral\<^sup>P to integral\<^sup>N.

  - replaced the Lebesgue integral on real numbers by the more general
    Bochner integral for functions into a real-normed vector space.

    integral_zero               ~>  integral_zero / integrable_zero
    integral_minus              ~>  integral_minus / integrable_minus
    integral_add                ~>  integral_add / integrable_add
    integral_diff               ~>  integral_diff / integrable_diff
    integral_setsum             ~>  integral_setsum / integrable_setsum
    integral_multc              ~>  integral_mult_left / integrable_mult_left
    integral_cmult              ~>  integral_mult_right / integrable_mult_right
    integral_triangle_inequality~>  integral_norm_bound
    integrable_nonneg           ~>  integrableI_nonneg
    integral_positive           ~>  integral_nonneg_AE
    integrable_abs_iff          ~>  integrable_abs_cancel
    positive_integral_lim_INF   ~>  nn_integral_liminf
    lebesgue_real_affine        ~>  lborel_real_affine
    borel_integral_has_integral ~>  has_integral_lebesgue_integral
    integral_indicator          ~>
         integral_real_indicator / integrable_real_indicator
    positive_integral_fst       ~>  nn_integral_fst'
    positive_integral_fst_measurable ~> nn_integral_fst
    positive_integral_snd_measurable ~> nn_integral_snd

    integrable_fst_measurable   ~>
         integral_fst / integrable_fst / AE_integrable_fst

    integrable_snd_measurable   ~>
         integral_snd / integrable_snd / AE_integrable_snd

    integral_monotone_convergence  ~>
         integral_monotone_convergence / integrable_monotone_convergence

    integral_monotone_convergence_at_top  ~>
         integral_monotone_convergence_at_top /

    has_integral_iff_positive_integral_lebesgue  ~>

    lebesgue_integral_has_integral  ~>

    positive_integral_lebesgue_has_integral  ~>
         integral_has_integral_lebesgue_nonneg /

    lebesgue_integral_real_affine  ~>

    has_integral_iff_positive_integral_lborel  ~>
         integral_has_integral_nonneg / integrable_has_integral_nonneg

    The following theorems where removed:


  - Formalized properties about exponentially, Erlang, and normal
    distributed random variables.

* HOL-Decision_Procs: Separate command 'approximate' for approximative
computation in src/HOL/Decision_Procs/Approximation.  Minor

*** Scala ***

* The signature and semantics of Document.Snapshot.cumulate_markup /
select_markup have been clarified.  Markup is now traversed in the
order of reports given by the prover: later markup is usually more
specific and may override results accumulated so far.  The elements
guard is mandatory and checked precisely.  Subtle INCOMPATIBILITY.

* Substantial reworking of internal PIDE protocol communication

*** ML ***

* Subtle change of semantics of Thm.eq_thm: theory stamps are not
compared (according to Thm.thm_ord), but assumed to be covered by the
current background theory.  Thus equivalent data produced in different
branches of the theory graph usually coincides (e.g. relevant for
theory merge).  Note that the softer Thm.eq_thm_prop is often more
appropriate than Thm.eq_thm.

* Proper context for basic Simplifier operations: rewrite_rule,
rewrite_goals_rule, rewrite_goals_tac etc. INCOMPATIBILITY, need to
pass runtime Proof.context (and ensure that the simplified entity
actually belongs to it).

* Proper context discipline for read_instantiate and instantiate_tac:
variables that are meant to become schematic need to be given as
fixed, and are generalized by the explicit context of local variables.
This corresponds to Isar attributes "where" and "of" with 'for'
declaration.  INCOMPATIBILITY, also due to potential change of indices
of schematic variables.

* Moved ML_Compiler.exn_trace and other operations on exceptions to
structure Runtime.  Minor INCOMPATIBILITY.

* Discontinued old Toplevel.debug in favour of system option
"ML_exception_trace", which may be also declared within the context
via "declare [[ML_exception_trace = true]]".  Minor INCOMPATIBILITY.

* Renamed configuration option "ML_trace" to "ML_source_trace". Minor

* Configuration option "ML_print_depth" controls the pretty-printing
depth of the ML compiler within the context.  The old print_depth in
ML is still available as default_print_depth, but rarely used.  Minor

* Toplevel function "use" refers to raw ML bootstrap environment,
without Isar context nor antiquotations.  Potential INCOMPATIBILITY.
Note that 'ML_file' is the canonical command to load ML files into the
formal context.

* Simplified programming interface to define ML antiquotations, see
structure ML_Antiquotation.  Minor INCOMPATIBILITY.

* ML antiquotation @{here} refers to its source position, which is
occasionally useful for experimentation and diagnostic purposes.

* ML antiquotation @{path} produces a Path.T value, similarly to
Path.explode, but with compile-time check against the file-system and
some PIDE markup.  Note that unlike theory source, ML does not have a
well-defined master directory, so an absolute symbolic path
specification is usually required, e.g. "~~/src/HOL".

* ML antiquotation @{print} inlines a function to print an arbitrary
ML value, which is occasionally useful for diagnostic or demonstration

*** System ***

* Proof General with its traditional helper scripts is now an optional
Isabelle component, e.g. see ProofGeneral-4.2-2 from the Isabelle
component repository  Note that
the "system" manual provides general explanations about add-on
components, especially those that are not bundled with the release.

* The raw Isabelle process executable has been renamed from
"isabelle-process" to "isabelle_process", which conforms to common
shell naming conventions, and allows to define a shell function within
the Isabelle environment to avoid dynamic path lookup.  Rare
incompatibility for old tools that do not use the ISABELLE_PROCESS
settings variable.

* Former "isabelle tty" has been superseded by "isabelle console",
with implicit build like "isabelle jedit", and without the mostly
obsolete Isar TTY loop.

* Simplified "isabelle display" tool.  Settings variables DVI_VIEWER
and PDF_VIEWER now refer to the actual programs, not shell
command-lines.  Discontinued option -c: invocation may be asynchronous
via desktop environment, without any special precautions.  Potential
INCOMPATIBILITY with ambitious private settings.

* Removed obsolete "isabelle unsymbolize".  Note that the usual format
for email communication is the Unicode rendering of Isabelle symbols,
as produced by Isabelle/jEdit, for example.

* Removed obsolete tool "wwwfind". Similar functionality may be
integrated into Isabelle/jEdit eventually.

* Improved 'display_drafts' concerning desktop integration and
repeated invocation in PIDE front-end: re-use single file
$ISABELLE_HOME_USER/tmp/drafts.pdf and corresponding views.

* Session ROOT specifications require explicit 'document_files' for
robust dependencies on LaTeX sources.  Only these explicitly given
files are copied to the document output directory, before document
processing is started.

* Windows: support for regular TeX installation (e.g. MiKTeX) instead
of TeX Live from Cygwin.

New in Isabelle2013-2 (December 2013)

*** Prover IDE -- Isabelle/Scala/jEdit ***

* More robust editing of running commands with internal forks,
e.g. non-terminating 'by' steps.

* More relaxed Sledgehammer panel: avoid repeated application of query
after edits surrounding the command location.

* More status information about commands that are interrupted
accidentally (via physical event or Poly/ML runtime system signal,
e.g. out-of-memory).

*** System ***

* More robust termination of external processes managed by
Isabelle/ML: support cancellation of tasks within the range of
milliseconds, as required for PIDE document editing with automatically
tried tools (e.g. Sledgehammer).

* Reactivated Isabelle/Scala kill command for external processes on
Mac OS X, which was accidentally broken in Isabelle2013-1 due to a
workaround for some Debian/Ubuntu Linux versions from 2013.

New in Isabelle2013-1 (November 2013)

*** General ***

* Discontinued obsolete 'uses' within theory header.  Note that
commands like 'ML_file' work without separate declaration of file
dependencies.  Minor INCOMPATIBILITY.

* Discontinued redundant 'use' command, which was superseded by
'ML_file' in Isabelle2013.  Minor INCOMPATIBILITY.

* Simplified subscripts within identifiers, using plain \<^sub>
instead of the second copy \<^isub> and \<^isup>.  Superscripts are
only for literal tokens within notation; explicit mixfix annotations
for consts or fixed variables may be used as fall-back for unusual
names.  Obsolete \<twosuperior> has been expanded to \<^sup>2 in
Isabelle/HOL.  INCOMPATIBILITY, use "isabelle update_sub_sup" to
standardize symbols as a starting point for further manual cleanup.
The ML reference variable "legacy_isub_isup" may be set as temporary
workaround, to make the prover accept a subset of the old identifier

* Document antiquotations: term style "isub" has been renamed to

* Uniform management of "quick_and_dirty" as system option (see also
"isabelle options"), configuration option within the context (see also
Config.get in Isabelle/ML), and attribute in Isabelle/Isar.  Minor
INCOMPATIBILITY, need to use more official Isabelle means to access
quick_and_dirty, instead of historical poking into mutable reference.

* Renamed command 'print_configs' to 'print_options'.  Minor

* Proper diagnostic command 'print_state'.  Old 'pr' (with its
implicit change of some global references) is retained for now as
control command, e.g. for ProofGeneral 3.7.x.

* Discontinued 'print_drafts' command with its old-fashioned PS output
and Unix command-line print spooling.  Minor INCOMPATIBILITY: use
'display_drafts' instead and print via the regular document viewer.

* Updated and extended "isar-ref" and "implementation" manual,
eliminated old "ref" manual.

*** Prover IDE -- Isabelle/Scala/jEdit ***

* New manual "jedit" for Isabelle/jEdit, see isabelle doc or
Documentation panel.

* Dockable window "Documentation" provides access to Isabelle

* Dockable window "Find" provides query operations for formal entities
(GUI front-end to 'find_theorems' command).

* Dockable window "Sledgehammer" manages asynchronous / parallel
sledgehammer runs over existing document sources, independently of
normal editing and checking process.

* Dockable window "Timing" provides an overview of relevant command
timing information, depending on option jedit_timing_threshold.  The
same timing information is shown in the extended tooltip of the
command keyword, when hovering the mouse over it while the CONTROL or
COMMAND modifier is pressed.

* Improved dockable window "Theories": Continuous checking of proof
document (visible and required parts) may be controlled explicitly,
using check box or shortcut "C+e ENTER".  Individual theory nodes may
be marked explicitly as required and checked in full, using check box
or shortcut "C+e SPACE".

* Improved completion mechanism, which is now managed by the
Isabelle/jEdit plugin instead of SideKick.  Refined table of Isabelle
symbol abbreviations (see $ISABELLE_HOME/etc/symbols).

* Standard jEdit keyboard shortcut C+b complete-word is remapped to
isabelle.complete for explicit completion in Isabelle sources.
INCOMPATIBILITY wrt. jEdit defaults, may have to invent new shortcuts
to resolve conflict.

* Improved support of various "minor modes" for Isabelle NEWS,
options, session ROOT etc., with completion and SideKick tree view.

* Strictly monotonic document update, without premature cancellation of
running transactions that are still needed: avoid reset/restart of
such command executions while editing.

* Support for asynchronous print functions, as overlay to existing
document content.

* Support for automatic tools in HOL, which try to prove or disprove
toplevel theorem statements.

* Action isabelle.reset-font-size resets main text area font size
according to Isabelle/Scala plugin option "jedit_font_reset_size" (see
also "Plugin Options / Isabelle / General").  It can be bound to some
keyboard shortcut by the user (e.g. C+0 and/or C+NUMPAD0).

* File specifications in jEdit (e.g. file browser) may refer to
$ISABELLE_HOME and $ISABELLE_HOME_USER on all platforms.  Discontinued
obsolete $ISABELLE_HOME_WINDOWS variable.

* Improved support for Linux look-and-feel "GTK+", see also "Utilities
/ Global Options / Appearance".

* Improved support of native Mac OS X functionality via "MacOSX"
plugin, which is now enabled by default.

*** Pure ***

* Commands 'interpretation' and 'sublocale' are now target-sensitive.
In particular, 'interpretation' allows for non-persistent
interpretation within "context ... begin ... end" blocks offering a
light-weight alternative to 'sublocale'.  See "isar-ref" manual for

* Improved locales diagnostic command 'print_dependencies'.

* Discontinued obsolete 'axioms' command, which has been marked as
legacy since Isabelle2009-2.  INCOMPATIBILITY, use 'axiomatization'
instead, while observing its uniform scope for polymorphism.

* Discontinued empty name bindings in 'axiomatization'.

* System option "proofs" has been discontinued.  Instead the global
state of Proofterm.proofs is persistently compiled into logic images
as required, notably HOL-Proofs.  Users no longer need to change
Proofterm.proofs dynamically.  Minor INCOMPATIBILITY.

* Syntax translation functions (print_translation etc.) always depend
on Proof.context.  Discontinued former "(advanced)" option -- this is
now the default.  Minor INCOMPATIBILITY.

* Former global reference trace_unify_fail is now available as
configuration option "unify_trace_failure" (global context only).

* SELECT_GOAL now retains the syntactic context of the overall goal
state (schematic variables etc.).  Potential INCOMPATIBILITY in rare

*** HOL ***

* Stronger precedence of syntax for big intersection and union on
sets, in accordance with corresponding lattice operations.

* Notation "{p:A. P}" now allows tuple patterns as well.

* Nested case expressions are now translated in a separate check phase
rather than during parsing. The data for case combinators is separated
from the datatype package. The declaration attribute
"case_translation" can be used to register new case combinators:

  declare [[case_translation case_combinator constructor1 ... constructorN]]

* Code generator:
  - 'code_printing' unifies 'code_const' / 'code_type' / 'code_class' /
  - 'code_identifier' declares name hints for arbitrary identifiers in
    generated code, subsuming 'code_modulename'.

See the isar-ref manual for syntax diagrams, and the HOL theories for

* Attibute 'code': 'code' now declares concrete and abstract code
equations uniformly.  Use explicit 'code equation' and 'code abstract'
to distinguish both when desired.

* Discontinued theories Code_Integer and Efficient_Nat by a more
fine-grain stack of theories Code_Target_Int, Code_Binary_Nat,
Code_Target_Nat and Code_Target_Numeral.  See the tutorial on code
generation for details.  INCOMPATIBILITY.

* Numeric types are mapped by default to target language numerals:
natural (replaces former code_numeral) and integer (replaces former
code_int).  Conversions are available as integer_of_natural /
natural_of_integer / integer_of_nat / nat_of_integer (in HOL) and
Code_Numeral.integer_of_natural / Code_Numeral.natural_of_integer (in

* Function package: For mutually recursive functions f and g, separate
cases rules f.cases and g.cases are generated instead of unusable
f_g.cases which exposed internal sum types. Potential INCOMPATIBILITY,
in the case that the unusable rule was used nevertheless.

* Function package: For each function f, new rules f.elims are
generated, which eliminate equalities of the form "f x = t".

* New command 'fun_cases' derives ad-hoc elimination rules for
function equations as simplified instances of f.elims, analogous to
inductive_cases.  See ~~/src/HOL/ex/Fundefs.thy for some examples.

* Lifting:
  - parametrized correspondence relations are now supported:
    + parametricity theorems for the raw term can be specified in
      the command lift_definition, which allow us to generate stronger
      transfer rules
    + setup_lifting generates stronger transfer rules if parametric
      correspondence relation can be generated
    + various new properties of the relator must be specified to support
    + parametricity theorem for the Quotient relation can be specified
  - setup_lifting generates domain rules for the Transfer package
  - stronger reflexivity prover of respectfulness theorems for type
  - ===> and --> are now local. The symbols can be introduced
    by interpreting the locale lifting_syntax (typically in an
    anonymous context)
  - Lifting/Transfer relevant parts of Library/Quotient_* are now in
    Main. Potential INCOMPATIBILITY
  - new commands for restoring and deleting Lifting/Transfer context:
    lifting_forget, lifting_update
  - the command print_quotmaps was renamed to print_quot_maps.

* Transfer:
  - better support for domains in Transfer: replace Domainp T
    by the actual invariant in a transferred goal
  - transfer rules can have as assumptions other transfer rules
  - Experimental support for transferring from the raw level to the
    abstract level: Transfer.transferred attribute
  - Attribute version of the transfer method: untransferred attribute

* Reification and reflection:
  - Reification is now directly available in HOL-Main in structure
  - Reflection now handles multiple lists with variables also.
  - The whole reflection stack has been decomposed into conversions.

* Revised devices for recursive definitions over finite sets:
  - Only one fundamental fold combinator on finite set remains:
    Finite_Set.fold :: ('a => 'b => 'b) => 'b => 'a set => 'b
    This is now identity on infinite sets.
  - Locales ("mini packages") for fundamental definitions with
    Finite_Set.fold: folding, folding_idem.
  - Locales comm_monoid_set, semilattice_order_set and
    semilattice_neutr_order_set for big operators on sets.
    See theory Big_Operators for canonical examples.
    Note that foundational constants comm_monoid_set.F and
    semilattice_set.F correspond to former combinators fold_image
    and fold1 respectively.  These are now gone.  You may use
    those foundational constants as substitutes, but it is
    preferable to interpret the above locales accordingly.
  - Dropped class ab_semigroup_idem_mult (special case of lattice,
    no longer needed in connection with Finite_Set.fold etc.)
  - Fact renames:
      card.union_inter ~> card_Un_Int [symmetric]
      card.union_disjoint ~> card_Un_disjoint

* Locale hierarchy for abstract orderings and (semi)lattices.

* Complete_Partial_Order.admissible is defined outside the type class
ccpo, but with mandatory prefix ccpo. Admissibility theorems lose the
class predicate assumption or sort constraint when possible.

* Introduce type class "conditionally_complete_lattice": Like a
complete lattice but does not assume the existence of the top and
bottom elements.  Allows to generalize some lemmas about reals and
extended reals.  Removed SupInf and replaced it by the instantiation
of conditionally_complete_lattice for real. Renamed lemmas about
conditionally-complete lattice from Sup_... to cSup_... and from
Inf_...  to cInf_... to avoid hidding of similar complete lattice

* Introduce type class linear_continuum as combination of
conditionally-complete lattices and inner dense linorders which have
more than one element.  INCOMPATIBILITY.

* Introduced type classes order_top and order_bot. The old classes top
and bot only contain the syntax without assumptions.  INCOMPATIBILITY:
Rename bot -> order_bot, top -> order_top

* Introduce type classes "no_top" and "no_bot" for orderings without
top and bottom elements.

* Split dense_linorder into inner_dense_order and no_top, no_bot.

* Complex_Main: Unify and move various concepts from
HOL-Multivariate_Analysis to HOL-Complex_Main.

 - Introduce type class (lin)order_topology and
   linear_continuum_topology.  Allows to generalize theorems about
   limits and order.  Instances are reals and extended reals.

 - continuous and continuos_on from Multivariate_Analysis:
   "continuous" is the continuity of a function at a filter.  "isCont"
   is now an abbrevitation: "isCont x f == continuous (at _) f".

   Generalized continuity lemmas from isCont to continuous on an
   arbitrary filter.

 - compact from Multivariate_Analysis. Use Bolzano's lemma to prove
   compactness of closed intervals on reals. Continuous functions
   attain infimum and supremum on compact sets. The inverse of a
   continuous function is continuous, when the function is continuous
   on a compact set.

 - connected from Multivariate_Analysis. Use it to prove the
   intermediate value theorem. Show connectedness of intervals on

 - first_countable_topology from Multivariate_Analysis. Is used to
   show equivalence of properties on the neighbourhood filter of x and
   on all sequences converging to x.

 - FDERIV: Definition of has_derivative moved to Deriv.thy. Moved
   theorems from Library/FDERIV.thy to Deriv.thy and base the
   definition of DERIV on FDERIV. Add variants of DERIV and FDERIV
   which are restricted to sets, i.e. to represent derivatives from
   left or right.

 - Removed the within-filter. It is replaced by the principal filter:

     F within X = inf F (principal X)

 - Introduce "at x within U" as a single constant, "at x" is now an
   abbreviation for "at x within UNIV"

 - Introduce named theorem collections tendsto_intros,
   continuous_intros, continuous_on_intros and FDERIV_intros. Theorems
   in tendsto_intros (or FDERIV_intros) are also available as
   tendsto_eq_intros (or FDERIV_eq_intros) where the right-hand side
   is replaced by a congruence rule. This allows to apply them as
   intro rules and then proving equivalence by the simplifier.

 - Restructured theories in HOL-Complex_Main:

   + Moved RealDef and RComplete into Real

   + Introduced Topological_Spaces and moved theorems about
     topological spaces, filters, limits and continuity to it

   + Renamed RealVector to Real_Vector_Spaces

   + Split Lim, SEQ, Series into Topological_Spaces,
     Real_Vector_Spaces, and Limits

   + Moved Ln and Log to Transcendental

   + Moved theorems about continuity from Deriv to Topological_Spaces

 - Remove various auxiliary lemmas.


* Nitpick:
  - Added option "spy".
  - Reduce incidence of "too high arity" errors.

* Sledgehammer:
  - Renamed option:
      isar_shrink ~> isar_compress
  - Added options "isar_try0", "spy".
  - Better support for "isar_proofs".
  - MaSh has been fined-tuned and now runs as a local server.

* Improved support for ad hoc overloading of constants (see also
isar-ref manual and ~~/src/HOL/ex/Adhoc_Overloading_Examples.thy).

* Library/Polynomial.thy:
  - Use lifting for primitive definitions.
  - Explicit conversions from and to lists of coefficients, used for
    generated code.
  - Replaced recursion operator poly_rec by fold_coeffs.
  - Prefer pre-existing gcd operation for gcd.
  - Fact renames:
    poly_eq_iff ~> poly_eq_poly_eq_iff
    poly_ext ~> poly_eqI
    expand_poly_eq ~> poly_eq_iff

* New Library/Simps_Case_Conv.thy: Provides commands simps_of_case and
case_of_simps to convert function definitions between a list of
equations with patterns on the lhs and a single equation with case
expressions on the rhs. See also Ex/Simps_Case_Conv_Examples.thy.

* New Library/FSet.thy: type of finite sets defined as a subtype of
sets defined by Lifting/Transfer.

* Discontinued theory src/HOL/Library/Eval_Witness.  INCOMPATIBILITY.

* Consolidation of library theories on product orders:

    Product_Lattice ~> Product_Order -- pointwise order on products
    Product_ord ~> Product_Lexorder -- lexicographic order on products


* Imperative-HOL: The MREC combinator is considered legacy and no
longer included by default. INCOMPATIBILITY, use partial_function
instead, or import theory Legacy_Mrec as a fallback.

* HOL-Algebra: Discontinued theories ~~/src/HOL/Algebra/abstract and
~~/src/HOL/Algebra/poly.  Existing theories should be based on
~~/src/HOL/Library/Polynomial instead.  The latter provides
integration with HOL's type classes for rings.  INCOMPATIBILITY.

  - Various improvements to BNF-based (co)datatype package, including
    new commands "primrec_new", "primcorec", and
    "datatype_new_compat", as well as documentation. See
    "datatypes.pdf" for details.
  - New "coinduction" method to avoid some boilerplate (compared to
  - Renamed keywords:
    data ~> datatype_new
    codata ~> codatatype
    bnf_def ~> bnf
  - Renamed many generated theorems, including
    discs ~> disc
    map_comp' ~> map_comp
    map_id' ~> map_id
    sels ~> sel
    set_map' ~> set_map
    sets ~> set

*** ML ***

* Spec_Check is a Quickcheck tool for Isabelle/ML.  The ML function
"check_property" allows to check specifications of the form "ALL x y
z. prop x y z".  See also ~~/src/Tools/Spec_Check/ with its
Examples.thy in particular.

* Improved printing of exception trace in Poly/ML 5.5.1, with regular
tracing output in the command transaction context instead of physical
stdout.  See also Toplevel.debug, Toplevel.debugging and

* ML type "theory" is now immutable, without any special treatment of
drafts or linear updates (which could lead to "stale theory" errors in
the past).  Discontinued obsolete operations like Theory.copy,
Theory.checkpoint, and the auxiliary type theory_ref.  Minor

* More uniform naming of goal functions for skipped proofs:

    Skip_Proof.prove  ~>  Goal.prove_sorry
    Skip_Proof.prove_global  ~>  Goal.prove_sorry_global


* Simplifier tactics and tools use proper Proof.context instead of
historic type simpset.  Old-style declarations like addsimps,
addsimprocs etc. operate directly on Proof.context.  Raw type simpset
retains its use as snapshot of the main Simplifier context, using
simpset_of and put_simpset on Proof.context.  INCOMPATIBILITY -- port
old tools by making them depend on (ctxt : Proof.context) instead of
(ss : simpset), then turn (simpset_of ctxt) into ctxt.

* Modifiers for classical wrappers (e.g. addWrapper, delWrapper)
operate on Proof.context instead of claset, for uniformity with addIs,
addEs, addDs etc. Note that claset_of and put_claset allow to manage
clasets separately from the context.

* Discontinued obsolete ML antiquotations @{claset} and @{simpset}.
INCOMPATIBILITY, use @{context} instead.

* Antiquotation @{theory_context A} is similar to @{theory A}, but
presents the result as initial Proof.context.

*** System ***

* Discontinued obsolete isabelle usedir, mkdir, make -- superseded by
"isabelle build" in Isabelle2013.  INCOMPATIBILITY.

* Discontinued obsolete isabelle-process options -f and -u (former
administrative aliases of option -e).  Minor INCOMPATIBILITY.

* Discontinued obsolete isabelle print tool, and PRINT_COMMAND
settings variable.

* Discontinued ISABELLE_DOC_FORMAT settings variable and historic
document formats: dvi.gz, ps, ps.gz -- the default document format is
always pdf.

* Isabelle settings variable ISABELLE_BUILD_JAVA_OPTIONS allows to
specify global resources of the JVM process run by isabelle build.

* Toplevel executable $ISABELLE_HOME/bin/isabelle_scala_script allows
to run Isabelle/Scala source files as standalone programs.

* Improved "isabelle keywords" tool (for old-style ProofGeneral
keyword tables): use Isabelle/Scala operations, which inspect outer
syntax without requiring to build sessions first.

* Sessions may be organized via 'chapter' specifications in the ROOT
file, which determines a two-level hierarchy of browser info.  The old
tree-like organization via implicit sub-session relation (with its
tendency towards erratic fluctuation of URLs) has been discontinued.
The default chapter is called "Unsorted".  Potential INCOMPATIBILITY
for HTML presentation of theories.

New in Isabelle2013 (February 2013)

*** General ***

* Theorem status about oracles and unfinished/failed future proofs is
no longer printed by default, since it is incompatible with
incremental / parallel checking of the persistent document model.  ML
function Thm.peek_status may be used to inspect a snapshot of the
ongoing evaluation process.  Note that in batch mode --- notably
isabelle build --- the system ensures that future proofs of all
accessible theorems in the theory context are finished (as before).

* Configuration option show_markup controls direct inlining of markup
into the printed representation of formal entities --- notably type
and sort constraints.  This enables Prover IDE users to retrieve that
information via tooltips in the output window, for example.

* Command 'ML_file' evaluates ML text from a file directly within the
theory, without any predeclaration via 'uses' in the theory header.

* Old command 'use' command and corresponding keyword 'uses' in the
theory header are legacy features and will be discontinued soon.
Tools that load their additional source files may imitate the
'ML_file' implementation, such that the system can take care of
dependencies properly.

* Discontinued obsolete method fastsimp / tactic fast_simp_tac, which
is called fastforce / fast_force_tac already since Isabelle2011-1.

* Updated and extended "isar-ref" and "implementation" manual, reduced
remaining material in old "ref" manual.

* Improved support for auxiliary contexts that indicate block structure
for specifications.  Nesting of "context fixes ... context assumes ..."
and "class ... context ...".

* Attribute "consumes" allows a negative value as well, which is
interpreted relatively to the total number of premises of the rule in
the target context.  This form of declaration is stable when exported
from a nested 'context' with additional assumptions.  It is the
preferred form for definitional packages, notably cases/rules produced
in HOL/inductive and HOL/function.

* More informative error messages for Isar proof commands involving
lazy enumerations (method applications etc.).

* Refined 'help' command to retrieve outer syntax commands according
to name patterns (with clickable results).

*** Prover IDE -- Isabelle/Scala/jEdit ***

* Parallel terminal proofs ('by') are enabled by default, likewise
proofs that are built into packages like 'datatype', 'function'.  This
allows to "run ahead" checking the theory specifications on the
surface, while the prover is still crunching on internal
justifications.  Unfinished / cancelled proofs are restarted as
required to complete full proof checking eventually.

* Improved output panel with tooltips, hyperlinks etc. based on the
same Rich_Text_Area as regular Isabelle/jEdit buffers.  Activation of
tooltips leads to some window that supports the same recursively,
which can lead to stacks of tooltips as the semantic document content
is explored.  ESCAPE closes the whole stack, individual windows may be
closed separately, or detached to become independent jEdit dockables.

* Improved support for commands that produce graph output: the text
message contains a clickable area to open a new instance of the graph
browser on demand.

* More robust incremental parsing of outer syntax (partial comments,
malformed symbols).  Changing the balance of open/close quotes and
comment delimiters works more conveniently with unfinished situations
that frequently occur in user interaction.

* More efficient painting and improved reactivity when editing large
files.  More scalable management of formal document content.

* Smarter handling of tracing messages: prover process pauses after
certain number of messages per command transaction, with some user
dialog to stop or continue.  This avoids swamping the front-end with
potentially infinite message streams.

* More plugin options and preferences, based on Isabelle/Scala.  The
jEdit plugin option panel provides access to some Isabelle/Scala
options, including tuning parameters for editor reactivity and color

* Dockable window "Symbols" provides some editing support for Isabelle

* Dockable window "Monitor" shows ML runtime statistics.  Note that
continuous display of the chart slows down the system.

* Improved editing support for control styles: subscript, superscript,
bold, reset of style -- operating on single symbols or text
selections.  Cf. keyboard shortcuts C+e DOWN/UP/RIGHT/LEFT.

* Actions isabelle.increase-font-size and isabelle.decrease-font-size
adjust the main text area font size, and its derivatives for output,
tooltips etc.  Cf. keyboard shortcuts C-PLUS and C-MINUS, which often
need to be adapted to local keyboard layouts.

* More reactive completion popup by default: use \t (TAB) instead of
\n (NEWLINE) to minimize intrusion into regular flow of editing.  See
also "Plugin Options / SideKick / General / Code Completion Options".

* Implicit check and build dialog of the specified logic session
image.  For example, HOL, HOLCF, HOL-Nominal can be produced on
demand, without bundling big platform-dependent heap images in the
Isabelle distribution.

* Uniform Java 7 platform on Linux, Mac OS X, Windows: recent updates
from Oracle provide better multi-platform experience.  This version is
now bundled exclusively with Isabelle.

*** Pure ***

* Code generation for Haskell: restrict unqualified imports from
Haskell Prelude to a small set of fundamental operations.

* Command 'export_code': relative file names are interpreted
relatively to master directory of current theory rather than the
rather arbitrary current working directory.  INCOMPATIBILITY.

* Discontinued obsolete attribute "COMP".  Potential INCOMPATIBILITY,
use regular rule composition via "OF" / "THEN", or explicit proof
structure instead.  Note that Isabelle/ML provides a variety of
operators like COMP, INCR_COMP, COMP_INCR, which need to be applied
with some care where this is really required.

* Command 'typ' supports an additional variant with explicit sort
constraint, to infer and check the most general type conforming to a
given sort.  Example (in HOL):

  typ "_ * _ * bool * unit" :: finite

* Command 'locale_deps' visualizes all locales and their relations as
a Hasse diagram.

*** HOL ***

* Sledgehammer:

  - Added MaSh relevance filter based on machine-learning; see the
    Sledgehammer manual for details.
  - Polished Isar proofs generated with "isar_proofs" option.
  - Rationalized type encodings ("type_enc" option).
  - Renamed "kill_provers" subcommand to "kill_all".
  - Renamed options:
      isar_proof ~> isar_proofs
      isar_shrink_factor ~> isar_shrink
      max_relevant ~> max_facts
      relevance_thresholds ~> fact_thresholds

* Quickcheck: added an optimisation for equality premises.  It is
switched on by default, and can be switched off by setting the
configuration quickcheck_optimise_equality to false.

* Quotient: only one quotient can be defined by quotient_type

* Lifting:
  - generation of an abstraction function equation in lift_definition
  - quot_del attribute
  - renamed no_abs_code -> no_code (INCOMPATIBILITY.)

* Simproc "finite_Collect" rewrites set comprehensions into pointfree

* Preprocessing of the code generator rewrites set comprehensions into
pointfree expressions.

* The SMT solver Z3 has now by default a restricted set of directly
supported features. For the full set of features (div/mod, nonlinear
arithmetic, datatypes/records) with potential proof reconstruction
failures, enable the configuration option "z3_with_extensions".  Minor

* Simplified 'typedef' specifications: historical options for implicit
set definition and alternative name have been discontinued.  The
former behavior of "typedef (open) t = A" is now the default, but
written just "typedef t = A".  INCOMPATIBILITY, need to adapt theories

* Removed constant "chars"; prefer "Enum.enum" on type "char"

* Moved operation product, sublists and n_lists from theory Enum to

* Theorem UN_o generalized to SUP_comp.  INCOMPATIBILITY.

* Class "comm_monoid_diff" formalises properties of bounded
subtraction, with natural numbers and multisets as typical instances.

* Added combinator "Option.these" with type "'a option set => 'a set".

* Theory "Transitive_Closure": renamed lemmas

  reflcl_tranclp -> reflclp_tranclp
  rtranclp_reflcl -> rtranclp_reflclp


* Theory "Rings": renamed lemmas (in class semiring)

  left_distrib ~> distrib_right
  right_distrib ~> distrib_left


* Generalized the definition of limits:

  - Introduced the predicate filterlim (LIM x F. f x :> G) which
    expresses that when the input values x converge to F then the
    output f x converges to G.

  - Added filters for convergence to positive (at_top) and negative
    infinity (at_bot).

  - Moved infinity in the norm (at_infinity) from
    Multivariate_Analysis to Complex_Main.

  - Removed real_tendsto_inf, it is superseded by "LIM x F. f x :>


* Theory "Library/Option_ord" provides instantiation of option type to
lattice type classes.

* Theory "Library/Multiset": renamed

    constant fold_mset ~> Multiset.fold
    fact fold_mset_commute ~> fold_mset_comm


* Renamed theory Library/List_Prefix to Library/Sublist, with related
changes as follows.

  - Renamed constants (and related lemmas)

      prefix ~> prefixeq
      strict_prefix ~> prefix

  - Replaced constant "postfix" by "suffixeq" with swapped argument
    order (i.e., "postfix xs ys" is now "suffixeq ys xs") and dropped
    old infix syntax "xs >>= ys"; use "suffixeq ys xs" instead.
    Renamed lemmas accordingly.

  - Added constant "list_hembeq" for homeomorphic embedding on
    lists. Added abbreviation "sublisteq" for special case
    "list_hembeq (op =)".

  - Theory Library/Sublist no longer provides "order" and "bot" type
    class instances for the prefix order (merely corresponding locale
    interpretations). The type class instances are now in theory

  - The sublist relation of theory Library/Sublist_Order is now based
    on "Sublist.sublisteq".  Renamed lemmas accordingly:

      le_list_append_le_same_iff ~> Sublist.sublisteq_append_le_same_iff
      le_list_append_mono ~> Sublist.list_hembeq_append_mono
      le_list_below_empty ~> Sublist.list_hembeq_Nil, Sublist.list_hembeq_Nil2
      le_list_Cons_EX ~> Sublist.list_hembeq_ConsD
      le_list_drop_Cons2 ~> Sublist.sublisteq_Cons2'
      le_list_drop_Cons_neq ~> Sublist.sublisteq_Cons2_neq
      le_list_drop_Cons ~> Sublist.sublisteq_Cons'
      le_list_drop_many ~> Sublist.sublisteq_drop_many
      le_list_filter_left ~> Sublist.sublisteq_filter_left
      le_list_rev_drop_many ~> Sublist.sublisteq_rev_drop_many
      le_list_rev_take_iff ~> Sublist.sublisteq_append
      le_list_same_length ~> Sublist.sublisteq_same_length
      le_list_take_many_iff ~> Sublist.sublisteq_append'
      less_eq_list.drop ~> less_eq_list_drop
      less_eq_list.induct ~> less_eq_list_induct
      not_le_list_length ~> Sublist.not_sublisteq_length


* New theory Library/Countable_Set.

* Theory Library/Debug and Library/Parallel provide debugging and
parallel execution for code generated towards Isabelle/ML.

* Theory Library/FuncSet: Extended support for Pi and extensional and
introduce the extensional dependent function space "PiE". Replaced
extensional_funcset by an abbreviation, and renamed lemmas from
extensional_funcset to PiE as follows:

  extensional_empty  ~>  PiE_empty
  extensional_funcset_empty_domain  ~>  PiE_empty_domain
  extensional_funcset_empty_range  ~>  PiE_empty_range
  extensional_funcset_arb  ~>  PiE_arb
  extensional_funcset_mem  ~>  PiE_mem
  extensional_funcset_extend_domainI  ~>  PiE_fun_upd
  extensional_funcset_restrict_domain  ~>  fun_upd_in_PiE
  extensional_funcset_extend_domain_eq  ~>  PiE_insert_eq
  card_extensional_funcset  ~>  card_PiE
  finite_extensional_funcset  ~>  finite_PiE


* Theory Library/FinFun: theory of almost everywhere constant
functions (supersedes the AFP entry "Code Generation for Functions as

* Theory Library/Phantom: generic phantom type to make a type
parameter appear in a constant's type.  This alternative to adding
TYPE('a) as another parameter avoids unnecessary closures in generated

* Theory Library/RBT_Impl: efficient construction of red-black trees
from sorted associative lists. Merging two trees with rbt_union may
return a structurally different tree than before.  Potential

* Theory Library/IArray: immutable arrays with code generation.

* Theory Library/Finite_Lattice: theory of finite lattices.

* HOL/Multivariate_Analysis: replaced

  "basis :: 'a::euclidean_space => nat => real"
  "\<Chi>\<Chi> :: (nat => real) => 'a::euclidean_space"

on euclidean spaces by using the inner product "_ \<bullet> _" with
vectors from the Basis set: "\<Chi>\<Chi> i. f i" is superseded by
"SUM i : Basis. f i * r i".

  With this change the following constants are also changed or removed:

    DIM('a) :: nat  ~>  card (Basis :: 'a set)   (is an abbreviation)
    a $$ i  ~>  inner a i  (where i : Basis)
    cart_base i  removed
    \<pi>, \<pi>'  removed

  Theorems about these constants where removed.

  Renamed lemmas:

    component_le_norm  ~>  Basis_le_norm
    euclidean_eq  ~>  euclidean_eq_iff
    differential_zero_maxmin_component  ~>  differential_zero_maxmin_cart
    euclidean_simps  ~>  inner_simps
    independent_basis  ~>  independent_Basis
    span_basis  ~>  span_Basis
    in_span_basis  ~>  in_span_Basis
    norm_bound_component_le  ~>  norm_boound_Basis_le
    norm_bound_component_lt  ~>  norm_boound_Basis_lt
    component_le_infnorm  ~>  Basis_le_infnorm


* HOL/Probability:

  - Added simproc "measurable" to automatically prove measurability.

  - Added induction rules for sigma sets with disjoint union
    (sigma_sets_induct_disjoint) and for Borel-measurable functions

  - Added the Daniell-Kolmogorov theorem (the existence the limit of a
    projective family).

* HOL/Cardinals: Theories of ordinals and cardinals (supersedes the
AFP entry "Ordinals_and_Cardinals").

* HOL/BNF: New (co)datatype package based on bounded natural functors
with support for mixed, nested recursion and interesting non-free

* HOL/Finite_Set and Relation: added new set and relation operations
expressed by Finite_Set.fold.

* New theory HOL/Library/RBT_Set: implementation of sets by red-black
trees for the code generator.

* HOL/Library/RBT and HOL/Library/Mapping have been converted to

* HOL/Set: renamed Set.project -> Set.filter

*** Document preparation ***

* Dropped legacy antiquotations "term_style" and "thm_style", since
styles may be given as arguments to "term" and "thm" already.
Discontinued legacy styles "prem1" .. "prem19".

* Default LaTeX rendering for \<euro> is now based on eurosym package,
instead of slightly exotic babel/greek.

* Document variant NAME may use different LaTeX entry point
document/root_NAME.tex if that file exists, instead of the common

* Simplified custom document/build script, instead of old-style
document/IsaMakefile.  Minor INCOMPATIBILITY.

*** ML ***

* The default limit for maximum number of worker threads is now 8,
instead of 4, in correspondence to capabilities of contemporary
hardware and Poly/ML runtime system.

* Type Seq.results and related operations support embedded error
messages within lazy enumerations, and thus allow to provide
informative errors in the absence of any usable results.

* Renamed Position.str_of to to emphasize that this is a
formal device to inline positions into message text, but not
necessarily printing visible text.

*** System ***

* Advanced support for Isabelle sessions and build management, see
"system" manual for the chapter of that name, especially the "isabelle
build" tool and its examples.  The "isabelle mkroot" tool prepares
session root directories for use with "isabelle build", similar to
former "isabelle mkdir" for "isabelle usedir".  Note that this affects
document preparation as well.  INCOMPATIBILITY, isabelle usedir /
mkdir / make are rendered obsolete.

* Discontinued obsolete Isabelle/build script, it is superseded by the
regular isabelle build tool.  For example:

  isabelle build -s -b HOL

* Discontinued obsolete "isabelle makeall".

* Discontinued obsolete IsaMakefile and ROOT.ML files from the
Isabelle distribution, except for rudimentary src/HOL/IsaMakefile that
provides some traditional targets that invoke "isabelle build".  Note
that this is inefficient!  Applications of Isabelle/HOL involving
"isabelle make" should be upgraded to use "isabelle build" directly.

* The "isabelle options" tool prints Isabelle system options, as
required for "isabelle build", for example.

* The "isabelle logo" tool produces EPS and PDF format simultaneously.
Minor INCOMPATIBILITY in command-line options.

* The "isabelle install" tool has now a simpler command-line.  Minor

* The "isabelle components" tool helps to resolve add-on components
that are not bundled, or referenced from a bare-bones repository
version of Isabelle.

* Settings variable ISABELLE_PLATFORM_FAMILY refers to the general
platform family: "linux", "macos", "windows".

* The ML system is configured as regular component, and no longer
picked up from some surrounding directory.  Potential INCOMPATIBILITY
for home-made settings.

* Improved ML runtime statistics (heap, threads, future tasks etc.).

* Discontinued support for Poly/ML 5.2.1, which was the last version
without exception positions and advanced ML compiler/toplevel

* Discontinued special treatment of Proof General -- no longer guess
PROOFGENERAL_HOME based on accidental file-system layout.  Minor
settings manually, or use a Proof General version that has been
bundled as Isabelle component.

New in Isabelle2012 (May 2012)

*** General ***

* Prover IDE (PIDE) improvements:

  - more robust Sledgehammer integration (as before the sledgehammer
    command-line needs to be typed into the source buffer)
  - markup for bound variables
  - markup for types of term variables (displayed as tooltips)
  - support for user-defined Isar commands within the running session
  - improved support for Unicode outside original 16bit range
    e.g. glyph for \<A> (thanks to jEdit 4.5.1)

* Forward declaration of outer syntax keywords within the theory
header -- minor INCOMPATIBILITY for user-defined commands.  Allow new
commands to be used in the same theory where defined.

* Auxiliary contexts indicate block structure for specifications with
additional parameters and assumptions.  Such unnamed contexts may be
nested within other targets, like 'theory', 'locale', 'class',
'instantiation' etc.  Results from the local context are generalized
accordingly and applied to the enclosing target context.  Example:

    fixes x y z :: 'a
    assumes xy: "x = y" and yz: "y = z"

  lemma my_trans: "x = z" using xy yz by simp


  thm my_trans

The most basic application is to factor-out context elements of
several fixes/assumes/shows theorem statements, e.g. see

Any other local theory specification element works within the "context
... begin ... end" block as well.

* Bundled declarations associate attributed fact expressions with a
given name in the context.  These may be later included in other
contexts.  This allows to manage context extensions casually, without
the logical dependencies of locales and locale interpretation.  See
commands 'bundle', 'include', 'including' etc. in the isar-ref manual.

* Commands 'lemmas' and 'theorems' allow local variables using 'for'
declaration, and results are standardized before being stored.  Thus
old-style "standard" after instantiation or composition of facts
becomes obsolete.  Minor INCOMPATIBILITY, due to potential change of
indices of schematic variables.

* Rule attributes in local theory declarations (e.g. locale or class)
are now statically evaluated: the resulting theorem is stored instead
of the original expression.  INCOMPATIBILITY in rare situations, where
the historic accident of dynamic re-evaluation in interpretations
etc. was exploited.

* New tutorial "Programming and Proving in Isabelle/HOL"
("prog-prove").  It completely supersedes "A Tutorial Introduction to
Structured Isar Proofs" ("isar-overview"), which has been removed.  It
also supersedes "Isabelle/HOL, A Proof Assistant for Higher-Order
Logic" as the recommended beginners tutorial, but does not cover all
of the material of that old tutorial.

* Updated and extended reference manuals: "isar-ref",
"implementation", "system"; reduced remaining material in old "ref"

*** Pure ***

* Command 'definition' no longer exports the foundational "raw_def"
into the user context.  Minor INCOMPATIBILITY, may use the regular
"def" result with attribute "abs_def" to imitate the old version.

* Attribute "abs_def" turns an equation of the form "f x y == t" into
"f == %x y. t", which ensures that "simp" or "unfold" steps always
expand it.  This also works for object-logic equality.  (Formerly
undocumented feature.)

* Sort constraints are now propagated in simultaneous statements, just
like type constraints.  INCOMPATIBILITY in rare situations, where
distinct sorts used to be assigned accidentally.  For example:

  lemma "P (x::'a::foo)" and "Q (y::'a::bar)"  -- "now illegal"

  lemma "P (x::'a)" and "Q (y::'a::bar)"
    -- "now uniform 'a::bar instead of default sort for first occurrence (!)"

* Rule composition via attribute "OF" (or ML functions OF/MRS) is more
tolerant against multiple unifiers, as long as the final result is
unique.  (As before, rules are composed in canonical right-to-left
order to accommodate newly introduced premises.)

* Renamed some inner syntax categories:

    num ~> num_token
    xnum ~> xnum_token
    xstr ~> str_token

Minor INCOMPATIBILITY.  Note that in practice "num_const" or
"num_position" etc. are mainly used instead (which also include
position information via constraints).

* Simplified configuration options for syntax ambiguity: see
"syntax_ambiguity_warning" and "syntax_ambiguity_limit" in isar-ref

* Discontinued configuration option "syntax_positions": atomic terms
in parse trees are always annotated by position constraints.

* Old code generator for SML and its commands 'code_module',
'code_library', 'consts_code', 'types_code' have been discontinued.
Use commands of the generic code generator instead.  INCOMPATIBILITY.

* Redundant attribute "code_inline" has been discontinued. Use
"code_unfold" instead.  INCOMPATIBILITY.

* Dropped attribute "code_unfold_post" in favor of the its dual
"code_abbrev", which yields a common pattern in definitions like

  definition [code_abbrev]: "f = t"


* Obsolete 'types' command has been discontinued.  Use 'type_synonym'

* Discontinued old "prems" fact, which used to refer to the accidental
collection of foundational premises in the context (already marked as
legacy since Isabelle2011).

*** HOL ***

* Type 'a set is now a proper type constructor (just as before
Isabelle2008).  Definitions mem_def and Collect_def have disappeared.
Non-trivial INCOMPATIBILITY.  For developments keeping predicates and
sets separate, it is often sufficient to rephrase some set S that has
been accidentally used as predicates by "%x. x : S", and some
predicate P that has been accidentally used as set by "{x. P x}".
Corresponding proofs in a first step should be pruned from any
tinkering with former theorems mem_def and Collect_def as far as

For developments which deliberately mix predicates and sets, a
planning step is necessary to determine what should become a predicate
and what a set.  It can be helpful to carry out that step in
Isabelle2011-1 before jumping right into the current release.

* Code generation by default implements sets as container type rather
than predicates.  INCOMPATIBILITY.

* New type synonym 'a rel = ('a * 'a) set

* The representation of numerals has changed.  Datatype "num"
represents strictly positive binary numerals, along with functions
"numeral :: num => 'a" and "neg_numeral :: num => 'a" to represent
positive and negated numeric literals, respectively.  See also
definitions in ~~/src/HOL/Num.thy.  Potential INCOMPATIBILITY, some
user theories may require adaptations as follows:

  - Theorems with number_ring or number_semiring constraints: These
    classes are gone; use comm_ring_1 or comm_semiring_1 instead.

  - Theories defining numeric types: Remove number, number_semiring,
    and number_ring instances. Defer all theorems about numerals until
    after classes one and semigroup_add have been instantiated.

  - Numeral-only simp rules: Replace each rule having a "number_of v"
    pattern with two copies, one for numeral and one for neg_numeral.

  - Theorems about subclasses of semiring_1 or ring_1: These classes
    automatically support numerals now, so more simp rules and
    simprocs may now apply within the proof.

  - Definitions and theorems using old constructors Pls/Min/Bit0/Bit1:
    Redefine using other integer operations.

* Transfer: New package intended to generalize the existing
"descending" method and related theorem attributes from the Quotient
package.  (Not all functionality is implemented yet, but future
development will focus on Transfer as an eventual replacement for the
corresponding parts of the Quotient package.)

  - transfer_rule attribute: Maintains a collection of transfer rules,
    which relate constants at two different types. Transfer rules may
    relate different type instances of the same polymorphic constant,
    or they may relate an operation on a raw type to a corresponding
    operation on an abstract type (quotient or subtype). For example:

    ((A ===> B) ===> list_all2 A ===> list_all2 B) map map
    (cr_int ===> cr_int ===> cr_int) (%(x,y) (u,v). (x+u, y+v)) plus_int

  - transfer method: Replaces a subgoal on abstract types with an
    equivalent subgoal on the corresponding raw types. Constants are
    replaced with corresponding ones according to the transfer rules.
    Goals are generalized over all free variables by default; this is
    necessary for variables whose types change, but can be overridden
    for specific variables with e.g. "transfer fixing: x y z".  The
    variant transfer' method allows replacing a subgoal with one that
    is logically stronger (rather than equivalent).

  - relator_eq attribute: Collects identity laws for relators of
    various type constructors, e.g. "list_all2 (op =) = (op =)".  The
    transfer method uses these lemmas to infer transfer rules for
    non-polymorphic constants on the fly.

  - transfer_prover method: Assists with proving a transfer rule for a
    new constant, provided the constant is defined in terms of other
    constants that already have transfer rules. It should be applied
    after unfolding the constant definitions.

  - HOL/ex/Transfer_Int_Nat.thy: Example theory demonstrating transfer
    from type nat to type int.

* Lifting: New package intended to generalize the quotient_definition
facility of the Quotient package; designed to work with Transfer.

  - lift_definition command: Defines operations on an abstract type in
    terms of a corresponding operation on a representation
    type.  Example syntax:

    lift_definition dlist_insert :: "'a => 'a dlist => 'a dlist"
      is List.insert

    Users must discharge a respectfulness proof obligation when each
    constant is defined. (For a type copy, i.e. a typedef with UNIV,
    the proof is discharged automatically.) The obligation is
    presented in a user-friendly, readable form; a respectfulness
    theorem in the standard format and a transfer rule are generated
    by the package.

  - Integration with code_abstype: For typedefs (e.g. subtypes
    corresponding to a datatype invariant, such as dlist),
    lift_definition generates a code certificate theorem and sets up
    code generation for each constant.

  - setup_lifting command: Sets up the Lifting package to work with a
    user-defined type. The user must provide either a quotient theorem
    or a type_definition theorem.  The package configures transfer
    rules for equality and quantifiers on the type, and sets up the
    lift_definition command to work with the type.

  - Usage examples: See Quotient_Examples/Lift_DList.thy,
    Quotient_Examples/Lift_RBT.thy, Quotient_Examples/Lift_FSet.thy,
    Word/Word.thy and Library/Float.thy.

* Quotient package:

  - The 'quotient_type' command now supports a 'morphisms' option with
    rep and abs functions, similar to typedef.

  - 'quotient_type' sets up new types to work with the Lifting and
    Transfer packages, as with 'setup_lifting'.

  - The 'quotient_definition' command now requires the user to prove a
    respectfulness property at the point where the constant is
    defined, similar to lift_definition; INCOMPATIBILITY.

  - Renamed predicate 'Quotient' to 'Quotient3', and renamed theorems
    accordingly, INCOMPATIBILITY.

* New diagnostic command 'find_unused_assms' to find potentially
superfluous assumptions in theorems using Quickcheck.

* Quickcheck:

  - Quickcheck returns variable assignments as counterexamples, which
    allows to reveal the underspecification of functions under test.
    For example, refuting "hd xs = x", it presents the variable
    assignment xs = [] and x = a1 as a counterexample, assuming that
    any property is false whenever "hd []" occurs in it.

    These counterexample are marked as potentially spurious, as
    Quickcheck also returns "xs = []" as a counterexample to the
    obvious theorem "hd xs = hd xs".

    After finding a potentially spurious counterexample, Quickcheck
    continues searching for genuine ones.

    By default, Quickcheck shows potentially spurious and genuine
    counterexamples. The option "genuine_only" sets quickcheck to only
    show genuine counterexamples.

  - The command 'quickcheck_generator' creates random and exhaustive
    value generators for a given type and operations.

    It generates values by using the operations as if they were
    constructors of that type.

  - Support for multisets.

  - Added "use_subtype" options.

  - Added "quickcheck_locale" configuration to specify how to process
    conjectures in a locale context.

* Nitpick: Fixed infinite loop caused by the 'peephole_optim' option
and affecting 'rat' and 'real'.

* Sledgehammer:
  - Integrated more tightly with SPASS, as described in the ITP 2012
    paper "More SPASS with Isabelle".
  - Made it try "smt" as a fallback if "metis" fails or times out.
  - Added support for the following provers: Alt-Ergo (via Why3 and
    TFF1), iProver, iProver-Eq.
  - Sped up the minimizer.
  - Added "lam_trans", "uncurry_aliases", and "minimize" options.
  - Renamed "slicing" ("no_slicing") option to "slice" ("dont_slice").
  - Renamed "sound" option to "strict".

* Metis: Added possibility to specify lambda translations scheme as a
parenthesized argument (e.g., "by (metis (lifting) ...)").

* SMT: Renamed "smt_fixed" option to "smt_read_only_certificates".

* Command 'try0': Renamed from 'try_methods'. INCOMPATIBILITY.

* New "case_product" attribute to generate a case rule doing multiple
case distinctions at the same time.  E.g.

  list.exhaust [case_product nat.exhaust]

produces a rule which can be used to perform case distinction on both
a list and a nat.

* New "eventually_elim" method as a generalized variant of the
eventually_elim* rules.  Supports structured proofs.

* Typedef with implicit set definition is considered legacy.  Use
"typedef (open)" form instead, which will eventually become the

* Record: code generation can be switched off manually with

  declare [[record_coden = false]]  -- "default true"

* Datatype: type parameters allow explicit sort constraints.

* Concrete syntax for case expressions includes constraints for source
positions, and thus produces Prover IDE markup for its bindings.
INCOMPATIBILITY for old-style syntax translations that augment the
pattern notation; e.g. see src/HOL/HOLCF/One.thy for translations of

* Clarified attribute "mono_set": pure declaration without modifying
the result of the fact expression.

* More default pred/set conversions on a couple of relation operations
and predicates.  Added powers of predicate relations.  Consolidation
of some relation theorems:

  converse_def ~> converse_unfold
  rel_comp_def ~> relcomp_unfold
  symp_def ~> (modified, use symp_def and sym_def instead)
  transp_def ~> transp_trans
  Domain_def ~> Domain_unfold
  Range_def ~> Domain_converse [symmetric]

Generalized theorems INF_INT_eq, INF_INT_eq2, SUP_UN_eq, SUP_UN_eq2.

See theory "Relation" for examples for making use of pred/set
conversions by means of attributes "to_set" and "to_pred".


* Renamed facts about the power operation on relations, i.e., relpow
to match the constant's name:

  rel_pow_1 ~> relpow_1
  rel_pow_0_I ~> relpow_0_I
  rel_pow_Suc_I ~> relpow_Suc_I
  rel_pow_Suc_I2 ~> relpow_Suc_I2
  rel_pow_0_E ~> relpow_0_E
  rel_pow_Suc_E ~> relpow_Suc_E
  rel_pow_E ~> relpow_E
  rel_pow_Suc_D2 ~> relpow_Suc_D2
  rel_pow_Suc_E2 ~> relpow_Suc_E2
  rel_pow_Suc_D2' ~> relpow_Suc_D2'
  rel_pow_E2 ~> relpow_E2
  rel_pow_add ~> relpow_add
  rel_pow_commute ~> relpow
  rel_pow_empty ~> relpow_empty:
  rtrancl_imp_UN_rel_pow ~> rtrancl_imp_UN_relpow
  rel_pow_imp_rtrancl ~> relpow_imp_rtrancl
  rtrancl_is_UN_rel_pow ~> rtrancl_is_UN_relpow
  rtrancl_imp_rel_pow ~> rtrancl_imp_relpow
  rel_pow_fun_conv ~> relpow_fun_conv
  rel_pow_finite_bounded1 ~> relpow_finite_bounded1
  rel_pow_finite_bounded ~> relpow_finite_bounded
  rtrancl_finite_eq_rel_pow ~> rtrancl_finite_eq_relpow
  trancl_finite_eq_rel_pow ~> trancl_finite_eq_relpow
  single_valued_rel_pow ~> single_valued_relpow


* Theory Relation: Consolidated constant name for relation composition
and corresponding theorem names:

  - Renamed constant rel_comp to relcomp.

  - Dropped abbreviation pred_comp. Use relcompp instead.

  - Renamed theorems:

    rel_compI ~> relcompI
    rel_compEpair ~> relcompEpair
    rel_compE ~> relcompE
    pred_comp_rel_comp_eq ~> relcompp_relcomp_eq
    rel_comp_empty1 ~> relcomp_empty1
    rel_comp_mono ~> relcomp_mono
    rel_comp_subset_Sigma ~> relcomp_subset_Sigma
    rel_comp_distrib ~> relcomp_distrib
    rel_comp_distrib2 ~> relcomp_distrib2
    rel_comp_UNION_distrib ~> relcomp_UNION_distrib
    rel_comp_UNION_distrib2 ~> relcomp_UNION_distrib2
    single_valued_rel_comp ~> single_valued_relcomp
    rel_comp_def ~> relcomp_unfold
    converse_rel_comp ~> converse_relcomp
    pred_compI ~> relcomppI
    pred_compE ~> relcomppE
    pred_comp_bot1 ~> relcompp_bot1
    pred_comp_bot2 ~> relcompp_bot2
    transp_pred_comp_less_eq ~> transp_relcompp_less_eq
    pred_comp_mono ~> relcompp_mono
    pred_comp_distrib ~> relcompp_distrib
    pred_comp_distrib2 ~> relcompp_distrib2
    converse_pred_comp ~> converse_relcompp

    finite_rel_comp ~> finite_relcomp

    set_rel_comp ~> set_relcomp


* Theory Divides: Discontinued redundant theorems about div and mod.
INCOMPATIBILITY, use the corresponding generic theorems instead.

  DIVISION_BY_ZERO ~> div_by_0, mod_by_0
  zdiv_self ~> div_self
  zmod_self ~> mod_self
  zdiv_zero ~> div_0
  zmod_zero ~> mod_0
  zdiv_zmod_equality ~> div_mod_equality2
  zdiv_zmod_equality2 ~> div_mod_equality
  zmod_zdiv_trivial ~> mod_div_trivial
  zdiv_zminus_zminus ~> div_minus_minus
  zmod_zminus_zminus ~> mod_minus_minus
  zdiv_zminus2 ~> div_minus_right
  zmod_zminus2 ~> mod_minus_right
  zdiv_minus1_right ~> div_minus1_right
  zmod_minus1_right ~> mod_minus1_right
  zdvd_mult_div_cancel ~> dvd_mult_div_cancel
  zmod_zmult1_eq ~> mod_mult_right_eq
  zpower_zmod ~> power_mod
  zdvd_zmod ~> dvd_mod
  zdvd_zmod_imp_zdvd ~> dvd_mod_imp_dvd
  mod_mult_distrib ~> mult_mod_left
  mod_mult_distrib2 ~> mult_mod_right

* Removed redundant theorems nat_mult_2 and nat_mult_2_right; use
generic mult_2 and mult_2_right instead. INCOMPATIBILITY.

* Finite_Set.fold now qualified.  INCOMPATIBILITY.

* Consolidated theorem names concerning fold combinators:

  inf_INFI_fold_inf ~> inf_INF_fold_inf
  sup_SUPR_fold_sup ~> sup_SUP_fold_sup
  INFI_fold_inf ~> INF_fold_inf
  SUPR_fold_sup ~> SUP_fold_sup
  union_set ~> union_set_fold
  minus_set ~> minus_set_fold
  INFI_set_fold ~> INF_set_fold
  SUPR_set_fold ~> SUP_set_fold
  INF_code ~> INF_set_foldr
  SUP_code ~> SUP_set_foldr
  foldr.simps ~> foldr.simps (in point-free formulation)
  foldr_fold_rev ~> foldr_conv_fold
  foldl_fold ~> foldl_conv_fold
  foldr_foldr ~> foldr_conv_foldl
  foldl_foldr ~> foldl_conv_foldr
  fold_set_remdups ~> fold_set_fold_remdups
  fold_set ~> fold_set_fold
  fold1_set ~> fold1_set_fold


* Dropped rarely useful theorems concerning fold combinators:
foldl_apply, foldl_fun_comm, foldl_rev, fold_weak_invariant,
rev_foldl_cons, fold_set_remdups, fold_set, fold_set1,
concat_conv_foldl, foldl_weak_invariant, foldl_invariant,
foldr_invariant, foldl_absorb0, foldl_foldr1_lemma, foldl_foldr1,
listsum_conv_fold, listsum_foldl, sort_foldl_insort, foldl_assoc,
foldr_conv_foldl, start_le_sum, elem_le_sum, sum_eq_0_conv.
INCOMPATIBILITY.  For the common phrases "%xs. List.foldr plus xs 0"
and "List.foldl plus 0", prefer "List.listsum".  Otherwise it can be
useful to boil down "List.foldr" and "List.foldl" to "List.fold" by
unfolding "foldr_conv_fold" and "foldl_conv_fold".

* Dropped lemmas minus_set_foldr, union_set_foldr, union_coset_foldr,
inter_coset_foldr, Inf_fin_set_foldr, Sup_fin_set_foldr,
Min_fin_set_foldr, Max_fin_set_foldr, Inf_set_foldr, Sup_set_foldr,
INF_set_foldr, SUP_set_foldr.  INCOMPATIBILITY.  Prefer corresponding
lemmas over fold rather than foldr, or make use of lemmas
fold_conv_foldr and fold_rev.

* Congruence rules Option.map_cong and Option.bind_cong for recursion
through option types.

* "Transitive_Closure.ntrancl": bounded transitive closure on

* Constant "Set.not_member" now qualified.  INCOMPATIBILITY.

* Theory Int: Discontinued many legacy theorems specific to type int.
INCOMPATIBILITY, use the corresponding generic theorems instead.

  zminus_zminus ~> minus_minus
  zminus_0 ~> minus_zero
  zminus_zadd_distrib ~> minus_add_distrib
  zadd_commute ~> add_commute
  zadd_assoc ~> add_assoc
  zadd_left_commute ~> add_left_commute
  zadd_ac ~> add_ac
  zmult_ac ~> mult_ac
  zadd_0 ~> add_0_left
  zadd_0_right ~> add_0_right
  zadd_zminus_inverse2 ~> left_minus
  zmult_zminus ~> mult_minus_left
  zmult_commute ~> mult_commute
  zmult_assoc ~> mult_assoc
  zadd_zmult_distrib ~> left_distrib
  zadd_zmult_distrib2 ~> right_distrib
  zdiff_zmult_distrib ~> left_diff_distrib
  zdiff_zmult_distrib2 ~> right_diff_distrib
  zmult_1 ~> mult_1_left
  zmult_1_right ~> mult_1_right
  zle_refl ~> order_refl
  zle_trans ~> order_trans
  zle_antisym ~> order_antisym
  zle_linear ~> linorder_linear
  zless_linear ~> linorder_less_linear
  zadd_left_mono ~> add_left_mono
  zadd_strict_right_mono ~> add_strict_right_mono
  zadd_zless_mono ~> add_less_le_mono
  int_0_less_1 ~> zero_less_one
  int_0_neq_1 ~> zero_neq_one
  zless_le ~> less_le
  zpower_zadd_distrib ~> power_add
  zero_less_zpower_abs_iff ~> zero_less_power_abs_iff
  zero_le_zpower_abs ~> zero_le_power_abs

* Theory Deriv: Renamed

  DERIV_nonneg_imp_nonincreasing ~> DERIV_nonneg_imp_nondecreasing

* Theory Library/Multiset: Improved code generation of multisets.

* Theory HOL/Library/Set_Algebras: Addition and multiplication on sets
are expressed via type classes again. The special syntax
\<oplus>/\<otimes> has been replaced by plain +/*. Removed constant
setsum_set, which is now subsumed by Big_Operators.setsum.

* Theory HOL/Library/Diagonalize has been removed. INCOMPATIBILITY,
use theory HOL/Library/Nat_Bijection instead.

* Theory HOL/Library/RBT_Impl: Backing implementation of red-black
trees is now inside a type class context.  Names of affected
operations and lemmas have been prefixed by rbt_.  INCOMPATIBILITY for
theories working directly with raw red-black trees, adapt the names as

  bulkload -> rbt_bulkload
  del_from_left -> rbt_del_from_left
  del_from_right -> rbt_del_from_right
  del -> rbt_del
  delete -> rbt_delete
  ins -> rbt_ins
  insert -> rbt_insert
  insertw -> rbt_insert_with
  insert_with_key -> rbt_insert_with_key
  map_entry -> rbt_map_entry
  lookup -> rbt_lookup
  sorted -> rbt_sorted
  tree_greater -> rbt_greater
  tree_less -> rbt_less
  tree_less_symbol -> rbt_less_symbol
  union -> rbt_union
  union_with -> rbt_union_with
  union_with_key -> rbt_union_with_key

  balance_left_sorted -> balance_left_rbt_sorted
  balance_left_tree_greater -> balance_left_rbt_greater
  balance_left_tree_less -> balance_left_rbt_less
  balance_right_sorted -> balance_right_rbt_sorted
  balance_right_tree_greater -> balance_right_rbt_greater
  balance_right_tree_less -> balance_right_rbt_less
  balance_sorted -> balance_rbt_sorted
  balance_tree_greater -> balance_rbt_greater
  balance_tree_less -> balance_rbt_less
  bulkload_is_rbt -> rbt_bulkload_is_rbt
  combine_sorted -> combine_rbt_sorted
  combine_tree_greater -> combine_rbt_greater
  combine_tree_less -> combine_rbt_less
  delete_in_tree -> rbt_delete_in_tree
  delete_is_rbt -> rbt_delete_is_rbt
  del_from_left_tree_greater -> rbt_del_from_left_rbt_greater
  del_from_left_tree_less -> rbt_del_from_left_rbt_less
  del_from_right_tree_greater -> rbt_del_from_right_rbt_greater
  del_from_right_tree_less -> rbt_del_from_right_rbt_less
  del_in_tree -> rbt_del_in_tree
  del_inv1_inv2 -> rbt_del_inv1_inv2
  del_sorted -> rbt_del_rbt_sorted
  del_tree_greater -> rbt_del_rbt_greater
  del_tree_less -> rbt_del_rbt_less
  dom_lookup_Branch -> dom_rbt_lookup_Branch
  entries_lookup -> entries_rbt_lookup
  finite_dom_lookup -> finite_dom_rbt_lookup
  insert_sorted -> rbt_insert_rbt_sorted
  insertw_is_rbt -> rbt_insertw_is_rbt
  insertwk_is_rbt -> rbt_insertwk_is_rbt
  insertwk_sorted -> rbt_insertwk_rbt_sorted
  insertw_sorted -> rbt_insertw_rbt_sorted
  ins_sorted -> ins_rbt_sorted
  ins_tree_greater -> ins_rbt_greater
  ins_tree_less -> ins_rbt_less
  is_rbt_sorted -> is_rbt_rbt_sorted
  lookup_balance -> rbt_lookup_balance
  lookup_bulkload -> rbt_lookup_rbt_bulkload
  lookup_delete -> rbt_lookup_rbt_delete
  lookup_Empty -> rbt_lookup_Empty
  lookup_from_in_tree -> rbt_lookup_from_in_tree
  lookup_in_tree -> rbt_lookup_in_tree
  lookup_ins -> rbt_lookup_ins
  lookup_insert -> rbt_lookup_rbt_insert
  lookup_insertw -> rbt_lookup_rbt_insertw
  lookup_insertwk -> rbt_lookup_rbt_insertwk
  lookup_keys -> rbt_lookup_keys
  lookup_map -> rbt_lookup_map
  lookup_map_entry -> rbt_lookup_rbt_map_entry
  lookup_tree_greater -> rbt_lookup_rbt_greater
  lookup_tree_less -> rbt_lookup_rbt_less
  lookup_union -> rbt_lookup_rbt_union
  map_entry_color_of -> rbt_map_entry_color_of
  map_entry_inv1 -> rbt_map_entry_inv1
  map_entry_inv2 -> rbt_map_entry_inv2
  map_entry_is_rbt -> rbt_map_entry_is_rbt
  map_entry_sorted -> rbt_map_entry_rbt_sorted
  map_entry_tree_greater -> rbt_map_entry_rbt_greater
  map_entry_tree_less -> rbt_map_entry_rbt_less
  map_tree_greater -> map_rbt_greater
  map_tree_less -> map_rbt_less
  map_sorted -> map_rbt_sorted
  paint_sorted -> paint_rbt_sorted
  paint_lookup -> paint_rbt_lookup
  paint_tree_greater -> paint_rbt_greater
  paint_tree_less -> paint_rbt_less
  sorted_entries -> rbt_sorted_entries
  tree_greater_eq_trans -> rbt_greater_eq_trans
  tree_greater_nit -> rbt_greater_nit
  tree_greater_prop -> rbt_greater_prop
  tree_greater_simps -> rbt_greater_simps
  tree_greater_trans -> rbt_greater_trans
  tree_less_eq_trans -> rbt_less_eq_trans
  tree_less_nit -> rbt_less_nit
  tree_less_prop -> rbt_less_prop
  tree_less_simps -> rbt_less_simps
  tree_less_trans -> rbt_less_trans
  tree_ord_props -> rbt_ord_props
  union_Branch -> rbt_union_Branch
  union_is_rbt -> rbt_union_is_rbt
  unionw_is_rbt -> rbt_unionw_is_rbt
  unionwk_is_rbt -> rbt_unionwk_is_rbt
  unionwk_sorted -> rbt_unionwk_rbt_sorted

* Theory HOL/Library/Float: Floating point numbers are now defined as
a subset of the real numbers.  All operations are defined using the
lifing-framework and proofs use the transfer method.  INCOMPATIBILITY.

  Changed Operations:
  float_abs -> abs
  float_nprt -> nprt
  float_pprt -> pprt
  pow2 -> use powr
  round_down -> float_round_down
  round_up -> float_round_up
  scale -> exponent

  Removed Operations:
  ceiling_fl, lb_mult, lb_mod, ub_mult, ub_mod

  Renamed Lemmas:
  abs_float_def -> Float.compute_float_abs
  bitlen_ge0 -> bitlen_nonneg
  bitlen.simps -> Float.compute_bitlen
  float_components -> Float_mantissa_exponent
  float_divl.simps -> Float.compute_float_divl
  float_divr.simps -> Float.compute_float_divr
  float_eq_odd -> mult_powr_eq_mult_powr_iff
  float_power -> real_of_float_power
  lapprox_posrat_def -> Float.compute_lapprox_posrat
  lapprox_rat.simps -> Float.compute_lapprox_rat
  le_float_def' -> Float.compute_float_le
  le_float_def -> less_eq_float.rep_eq
  less_float_def' -> Float.compute_float_less
  less_float_def -> less_float.rep_eq
  normfloat_def -> Float.compute_normfloat
  normfloat_imp_odd_or_zero -> mantissa_not_dvd and mantissa_noteq_0
  normfloat -> normfloat_def
  normfloat_unique -> use normfloat_def
  number_of_float_Float -> Float.compute_float_numeral, Float.compute_float_neg_numeral
  one_float_def -> Float.compute_float_one
  plus_float_def -> Float.compute_float_plus
  rapprox_posrat_def -> Float.compute_rapprox_posrat
  rapprox_rat.simps -> Float.compute_rapprox_rat
  real_of_float_0 -> zero_float.rep_eq
  real_of_float_1 -> one_float.rep_eq
  real_of_float_abs -> abs_float.rep_eq
  real_of_float_add -> plus_float.rep_eq
  real_of_float_minus -> uminus_float.rep_eq
  real_of_float_mult -> times_float.rep_eq
  real_of_float_simp -> Float.rep_eq
  real_of_float_sub -> minus_float.rep_eq
  round_down.simps -> Float.compute_float_round_down
  round_up.simps -> Float.compute_float_round_up
  times_float_def -> Float.compute_float_times
  uminus_float_def -> Float.compute_float_uminus
  zero_float_def -> Float.compute_float_zero

  Lemmas not necessary anymore, use the transfer method:
  bitlen_B0, bitlen_B1, bitlen_ge1, bitlen_Min, bitlen_Pls, float_divl,
  float_divr, float_le_simp, float_less1_mantissa_bound,
  float_less_simp, float_less_zero, float_le_zero,
  float_pos_less1_e_neg, float_pos_m_pos, float_split, float_split2,
  floor_pos_exp, lapprox_posrat, lapprox_posrat_bottom, lapprox_rat,
  lapprox_rat_bottom, normalized_float, rapprox_posrat,
  rapprox_posrat_le1, rapprox_rat, real_of_float_ge0_exp,
  real_of_float_neg_exp, real_of_float_nge0_exp, round_down floor_fl,
  round_up, zero_le_float, zero_less_float

* New theory HOL/Library/DAList provides an abstract type for
association lists with distinct keys.

* Session HOL/IMP: Added new theory of abstract interpretation of
annotated commands.

* Session HOL-Import: Re-implementation from scratch is faster,
simpler, and more scalable.  Requires a proof bundle, which is
available as an external component.  Discontinued old (and mostly
dead) Importer for HOL4 and HOL Light.  INCOMPATIBILITY.

* Session HOL-Word: Discontinued many redundant theorems specific to
type 'a word. INCOMPATIBILITY, use the corresponding generic theorems

  word_sub_alt ~> word_sub_wi
  word_add_alt ~> word_add_def
  word_mult_alt ~> word_mult_def
  word_minus_alt ~> word_minus_def
  word_0_alt ~> word_0_wi
  word_1_alt ~> word_1_wi
  word_add_0 ~> add_0_left
  word_add_0_right ~> add_0_right
  word_mult_1 ~> mult_1_left
  word_mult_1_right ~> mult_1_right
  word_add_commute ~> add_commute
  word_add_assoc ~> add_assoc
  word_add_left_commute ~> add_left_commute
  word_mult_commute ~> mult_commute
  word_mult_assoc ~> mult_assoc
  word_mult_left_commute ~> mult_left_commute
  word_left_distrib ~> left_distrib
  word_right_distrib ~> right_distrib
  word_left_minus ~> left_minus
  word_diff_0_right ~> diff_0_right
  word_diff_self ~> diff_self
  word_sub_def ~> diff_minus
  word_diff_minus ~> diff_minus
  word_add_ac ~> add_ac
  word_mult_ac ~> mult_ac
  word_plus_ac0 ~> add_0_left add_0_right add_ac
  word_times_ac1 ~> mult_1_left mult_1_right mult_ac
  word_order_trans ~> order_trans
  word_order_refl ~> order_refl
  word_order_antisym ~> order_antisym
  word_order_linear ~> linorder_linear
  lenw1_zero_neq_one ~> zero_neq_one
  word_number_of_eq ~> number_of_eq
  word_of_int_add_hom ~> wi_hom_add
  word_of_int_sub_hom ~> wi_hom_sub
  word_of_int_mult_hom ~> wi_hom_mult
  word_of_int_minus_hom ~> wi_hom_neg
  word_of_int_succ_hom ~> wi_hom_succ
  word_of_int_pred_hom ~> wi_hom_pred
  word_of_int_0_hom ~> word_0_wi
  word_of_int_1_hom ~> word_1_wi

* Session HOL-Word: New proof method "word_bitwise" for splitting
machine word equalities and inequalities into logical circuits,
defined in HOL/Word/WordBitwise.thy.  Supports addition, subtraction,
multiplication, shifting by constants, bitwise operators and numeric
constants.  Requires fixed-length word types, not 'a word.  Solves
many standard word identities outright and converts more into first
order problems amenable to blast or similar.  See also examples in

* Session HOL-Probability: Introduced the type "'a measure" to
represent measures, this replaces the records 'a algebra and 'a
measure_space.  The locales based on subset_class now have two
locale-parameters the space \<Omega> and the set of measurable sets M.
The product of probability spaces uses now the same constant as the
finite product of sigma-finite measure spaces "PiM :: ('i => 'a)
measure".  Most constants are defined now outside of locales and gain
an additional parameter, like null_sets, almost_eventually or \<mu>'.
Measure space constructions for distributions and densities now got
their own constants distr and density.  Instead of using locales to
describe measure spaces with a finite space, the measure count_space
and point_measure is introduced.  INCOMPATIBILITY.

  Renamed constants:
  measure -> emeasure
  finite_measure.\<mu>' -> measure
  product_algebra_generator -> prod_algebra
  product_prob_space.emb -> prod_emb
  product_prob_space.infprod_algebra -> PiM

  Removed locales:

  Removed constants:
  distribution -> use distr measure, or distributed predicate
  joint_distribution -> use distr measure, or distributed predicate
  product_prob_space.infprod_algebra -> use PiM

  Replacement theorems:
  finite_additivity_sufficient -> ring_of_sets.countably_additiveI_finite
  finite_measure.empty_measure -> measure_empty
  finite_measure.finite_continuity_from_above -> finite_measure.finite_Lim_measure_decseq
  finite_measure.finite_continuity_from_below -> finite_measure.finite_Lim_measure_incseq
  finite_measure.finite_measure_countably_subadditive -> finite_measure.finite_measure_subadditive_countably
  finite_measure.finite_measure_eq -> finite_measure.emeasure_eq_measure
  finite_measure.finite_measure -> finite_measure.emeasure_finite
  finite_measure.finite_measure_finite_singleton -> finite_measure.finite_measure_eq_setsum_singleton
  finite_measure.positive_measure' -> measure_nonneg
  finite_measure.real_measure -> finite_measure.emeasure_real
  finite_product_prob_space.finite_measure_times -> finite_product_prob_space.finite_measure_PiM_emb
  finite_product_sigma_algebra.in_P -> sets_PiM_I_finite
  finite_product_sigma_algebra.P_empty -> space_PiM_empty, sets_PiM_empty
  information_space.conditional_entropy_eq -> information_space.conditional_entropy_simple_distributed
  information_space.conditional_entropy_positive -> information_space.conditional_entropy_nonneg_simple
  information_space.conditional_mutual_information_eq_mutual_information -> information_space.conditional_mutual_information_eq_mutual_information_simple
  information_space.conditional_mutual_information_generic_positive -> information_space.conditional_mutual_information_nonneg_simple
  information_space.conditional_mutual_information_positive -> information_space.conditional_mutual_information_nonneg_simple
  information_space.entropy_commute -> information_space.entropy_commute_simple
  information_space.entropy_eq -> information_space.entropy_simple_distributed
  information_space.entropy_generic_eq -> information_space.entropy_simple_distributed
  information_space.entropy_positive -> information_space.entropy_nonneg_simple
  information_space.entropy_uniform_max -> information_space.entropy_uniform
  information_space.KL_eq_0_imp -> information_space.KL_eq_0_iff_eq
  information_space.KL_eq_0 -> information_space.KL_same_eq_0
  information_space.KL_ge_0 -> information_space.KL_nonneg
  information_space.mutual_information_eq -> information_space.mutual_information_simple_distributed
  information_space.mutual_information_positive -> information_space.mutual_information_nonneg_simple
  Int_stable_cuboids -> Int_stable_atLeastAtMost
  Int_stable_product_algebra_generator -> positive_integral
  measure_preserving -> equality "distr M N f = N" "f : measurable M N"
  measure_space.additive -> emeasure_additive
  measure_space.AE_iff_null_set -> AE_iff_null
  measure_space.almost_everywhere_def -> eventually_ae_filter
  measure_space.almost_everywhere_vimage -> AE_distrD
  measure_space.continuity_from_above -> INF_emeasure_decseq
  measure_space.continuity_from_above_Lim -> Lim_emeasure_decseq
  measure_space.continuity_from_below_Lim -> Lim_emeasure_incseq
  measure_space.continuity_from_below -> SUP_emeasure_incseq
  measure_space_density -> emeasure_density
  measure_space.density_is_absolutely_continuous -> absolutely_continuousI_density
  measure_space.integrable_vimage -> integrable_distr
  measure_space.integral_translated_density -> integral_density
  measure_space.integral_vimage -> integral_distr
  measure_space.measure_additive -> plus_emeasure
  measure_space.measure_compl -> emeasure_compl
  measure_space.measure_countable_increasing -> emeasure_countable_increasing
  measure_space.measure_countably_subadditive -> emeasure_subadditive_countably
  measure_space.measure_decseq -> decseq_emeasure
  measure_space.measure_Diff -> emeasure_Diff
  measure_space.measure_Diff_null_set -> emeasure_Diff_null_set
  measure_space.measure_eq_0 -> emeasure_eq_0
  measure_space.measure_finitely_subadditive -> emeasure_subadditive_finite
  measure_space.measure_finite_singleton -> emeasure_eq_setsum_singleton
  measure_space.measure_incseq -> incseq_emeasure
  measure_space.measure_insert -> emeasure_insert
  measure_space.measure_mono -> emeasure_mono
  measure_space.measure_not_negative -> emeasure_not_MInf
  measure_space.measure_preserving_Int_stable -> measure_eqI_generator_eq
  measure_space.measure_setsum -> setsum_emeasure
  measure_space.measure_setsum_split -> setsum_emeasure_cover
  measure_space.measure_space_vimage -> emeasure_distr
  measure_space.measure_subadditive_finite -> emeasure_subadditive_finite
  measure_space.measure_subadditive -> subadditive
  measure_space.measure_top -> emeasure_space
  measure_space.measure_UN_eq_0 -> emeasure_UN_eq_0
  measure_space.measure_Un_null_set -> emeasure_Un_null_set
  measure_space.positive_integral_translated_density -> positive_integral_density
  measure_space.positive_integral_vimage -> positive_integral_distr
  measure_space.real_continuity_from_above -> Lim_measure_decseq
  measure_space.real_continuity_from_below -> Lim_measure_incseq
  measure_space.real_measure_countably_subadditive -> measure_subadditive_countably
  measure_space.real_measure_Diff -> measure_Diff
  measure_space.real_measure_finite_Union -> measure_finite_Union
  measure_space.real_measure_setsum_singleton -> measure_eq_setsum_singleton
  measure_space.real_measure_subadditive -> measure_subadditive
  measure_space.real_measure_Union -> measure_Union
  measure_space.real_measure_UNION -> measure_UNION
  measure_space.simple_function_vimage -> simple_function_comp
  measure_space.simple_integral_vimage -> simple_integral_distr
  measure_space.simple_integral_vimage -> simple_integral_distr
  measure_unique_Int_stable -> measure_eqI_generator_eq
  measure_unique_Int_stable_vimage -> measure_eqI_generator_eq
  pair_sigma_algebra.measurable_cut_fst -> sets_Pair1
  pair_sigma_algebra.measurable_cut_snd -> sets_Pair2
  pair_sigma_algebra.measurable_pair_image_fst -> measurable_Pair1
  pair_sigma_algebra.measurable_pair_image_snd -> measurable_Pair2
  pair_sigma_algebra.measurable_product_swap -> measurable_pair_swap_iff
  pair_sigma_algebra.pair_sigma_algebra_measurable -> measurable_pair_swap
  pair_sigma_algebra.pair_sigma_algebra_swap_measurable -> measurable_pair_swap'
  pair_sigma_algebra.sets_swap -> sets_pair_swap
  pair_sigma_finite.measure_cut_measurable_fst -> pair_sigma_finite.measurable_emeasure_Pair1
  pair_sigma_finite.measure_cut_measurable_snd -> pair_sigma_finite.measurable_emeasure_Pair2
  pair_sigma_finite.measure_preserving_swap -> pair_sigma_finite.distr_pair_swap
  pair_sigma_finite.pair_measure_alt2 -> pair_sigma_finite.emeasure_pair_measure_alt2
  pair_sigma_finite.pair_measure_alt -> pair_sigma_finite.emeasure_pair_measure_alt
  pair_sigma_finite.pair_measure_times -> pair_sigma_finite.emeasure_pair_measure_Times
  prob_space.indep_distribution_eq_measure -> prob_space.indep_vars_iff_distr_eq_PiM
  prob_space.indep_var_distributionD -> prob_space.indep_var_distribution_eq
  prob_space.measure_space_1 -> prob_space.emeasure_space_1
  prob_space.prob_space_vimage -> prob_space_distr
  prob_space.random_variable_restrict -> measurable_restrict
  prob_space_unique_Int_stable -> measure_eqI_prob_space
  product_algebraE -> prod_algebraE_all
  product_algebra_generator_der -> prod_algebra_eq_finite
  product_algebra_generator_into_space -> prod_algebra_sets_into_space
  product_algebraI -> sets_PiM_I_finite
  product_measure_exists -> product_sigma_finite.sigma_finite
  product_prob_space.finite_index_eq_finite_product -> product_prob_space.sets_PiM_generator
  product_prob_space.finite_measure_infprod_emb_Pi -> product_prob_space.measure_PiM_emb
  product_prob_space.infprod_spec -> product_prob_space.emeasure_PiM_emb_not_empty
  product_prob_space.measurable_component -> measurable_component_singleton
  product_prob_space.measurable_emb -> measurable_prod_emb
  product_prob_space.measurable_into_infprod_algebra -> measurable_PiM_single
  product_prob_space.measurable_singleton_infprod -> measurable_component_singleton
  product_prob_space.measure_emb -> emeasure_prod_emb
  product_prob_space.measure_preserving_restrict -> product_prob_space.distr_restrict
  product_sigma_algebra.product_algebra_into_space -> space_closed
  product_sigma_finite.measure_fold -> product_sigma_finite.distr_merge
  product_sigma_finite.measure_preserving_component_singelton -> product_sigma_finite.distr_singleton
  product_sigma_finite.measure_preserving_merge -> product_sigma_finite.distr_merge
  sequence_space.measure_infprod -> sequence_space.measure_PiM_countable
  sets_product_algebra -> sets_PiM
  sigma_algebra.measurable_sigma -> measurable_measure_of
  sigma_finite_measure.disjoint_sigma_finite -> sigma_finite_disjoint
  sigma_finite_measure.RN_deriv_vimage -> sigma_finite_measure.RN_deriv_distr
  sigma_product_algebra_sigma_eq -> sigma_prod_algebra_sigma_eq
  space_product_algebra -> space_PiM

* Session HOL-TPTP: support to parse and import TPTP problems (all
languages) into Isabelle/HOL.

*** FOL ***

* New "case_product" attribute (see HOL).

*** ZF ***

* Greater support for structured proofs involving induction or case

* Much greater use of mathematical symbols.

* Removal of many ML theorem bindings.  INCOMPATIBILITY.

*** ML ***

* Antiquotation @{keyword "name"} produces a parser for outer syntax
from a minor keyword introduced via theory header declaration.

* Antiquotation @{command_spec "name"} produces the
Outer_Syntax.command_spec from a major keyword introduced via theory
header declaration; it can be passed to Outer_Syntax.command etc.

* Local_Theory.define no longer hard-wires default theorem name
"foo_def", but retains the binding as given.  If that is Binding.empty
/ Attrib.empty_binding, the result is not registered as user-level
fact.  The Local_Theory.define_internal variant allows to specify a
non-empty name (used for the foundation in the background theory),
while omitting the fact binding in the user-context.  Potential
INCOMPATIBILITY for derived definitional packages: need to specify
naming policy for primitive definitions more explicitly.

* Renamed Thm.capply to Thm.apply, and Thm.cabs to Thm.lambda in
conformance with similar operations in structure Term and Logic.

* Antiquotation @{attributes [...]} embeds attribute source
representation into the ML text, which is particularly useful with
declarations like Local_Theory.note.

* Structure Proof_Context follows standard naming scheme.  Old
ProofContext has been discontinued.  INCOMPATIBILITY.

* Refined Local_Theory.declaration {syntax, pervasive}, with subtle
change of semantics: update is applied to auxiliary local theory
context as well.

* Modernized some old-style infix operations:

  addeqcongs    ~> Simplifier.add_eqcong
  deleqcongs    ~> Simplifier.del_eqcong
  addcongs      ~> Simplifier.add_cong
  delcongs      ~> Simplifier.del_cong
  setmksimps    ~> Simplifier.set_mksimps
  setmkcong     ~> Simplifier.set_mkcong
  setmksym      ~> Simplifier.set_mksym
  setmkeqTrue   ~> Simplifier.set_mkeqTrue
  settermless   ~> Simplifier.set_termless
  setsubgoaler  ~> Simplifier.set_subgoaler
  addsplits     ~> Splitter.add_split
  delsplits     ~> Splitter.del_split

*** System ***

* USER_HOME settings variable points to cross-platform user home
directory, which coincides with HOME on POSIX systems only.  Likewise,
the Isabelle path specification "~" now expands to $USER_HOME, instead
of former $HOME.  A different default for USER_HOME may be set
explicitly in shell environment, before Isabelle settings are
evaluated.  Minor INCOMPATIBILITY: need to adapt Isabelle path where
the generic user home was intended.

* ISABELLE_HOME_WINDOWS refers to ISABELLE_HOME in windows file name
notation, which is useful for the jEdit file browser, for example.

* ISABELLE_JDK_HOME settings variable points to JDK with javac and jar
(not just JRE).

New in Isabelle2011-1 (October 2011)

*** General ***

* Improved Isabelle/jEdit Prover IDE (PIDE), which can be invoked as
"isabelle jedit" or "ISABELLE_HOME/Isabelle" on the command line.

  - Management of multiple theory files directly from the editor
    buffer store -- bypassing the file-system (no requirement to save
    files for checking).

  - Markup of formal entities within the text buffer, with semantic
    highlighting, tooltips and hyperlinks to jump to defining source

  - Improved text rendering, with sub/superscripts in the source
    buffer (including support for copy/paste wrt. output panel, HTML
    theory output and other non-Isabelle text boxes).

  - Refined scheduling of proof checking and printing of results,
    based on interactive editor view.  (Note: jEdit folding and
    narrowing allows to restrict buffer perspectives explicitly.)

  - Reduced CPU performance requirements, usable on machines with few

  - Reduced memory requirements due to pruning of unused document
    versions (garbage collection).

See also ~~/src/Tools/jEdit/README.html for further information,
including some remaining limitations.

* Theory loader: source files are exclusively located via the master
directory of each theory node (where the .thy file itself resides).
The global load path (such as src/HOL/Library) has been discontinued.
Note that the path element ~~ may be used to reference theories in the
Isabelle home folder -- for instance, "~~/src/HOL/Library/FuncSet".

* Theory loader: source files are identified by content via SHA1
digests.  Discontinued former path/modtime identification and optional
ISABELLE_FILE_IDENT plugin scripts.

* Parallelization of nested Isar proofs is subject to
Goal.parallel_proofs_threshold (default 100).  See also isabelle
usedir option -Q.

* Name space: former unsynchronized references are now proper
configuration options, with more conventional names:

  long_names   ~> names_long
  short_names  ~> names_short
  unique_names ~> names_unique

Minor INCOMPATIBILITY, need to declare options in context like this:

  declare [[names_unique = false]]

* Literal facts `prop` may contain dummy patterns, e.g. `_ = _`.  Note
that the result needs to be unique, which means fact specifications
may have to be refined after enriching a proof context.

* Attribute "case_names" has been refined: the assumptions in each case
can be named now by following the case name with [name1 name2 ...].

* Isabelle/Isar reference manual has been updated and extended:
  - "Synopsis" provides a catalog of main Isar language concepts.
  - Formal references in syntax diagrams, via @{rail} antiquotation.
  - Updated material from classic "ref" manual, notably about
    "Classical Reasoner".

*** HOL ***

* Class bot and top require underlying partial order rather than
preorder: uniqueness of bot and top is guaranteed.  INCOMPATIBILITY.

* Class complete_lattice: generalized a couple of lemmas from sets;
generalized theorems INF_cong and SUP_cong.  New type classes for
complete boolean algebras and complete linear orders.  Lemmas
Inf_less_iff, less_Sup_iff, INF_less_iff, less_SUP_iff now reside in
class complete_linorder.

Changed proposition of lemmas Inf_bool_def, Sup_bool_def, Inf_fun_def,
Sup_fun_def, Inf_apply, Sup_apply.

Removed redundant lemmas (the right hand side gives hints how to
replace them for (metis ...), or (simp only: ...) proofs):

  Inf_singleton ~> Inf_insert [where A="{}", unfolded Inf_empty inf_top_right]
  Sup_singleton ~> Sup_insert [where A="{}", unfolded Sup_empty sup_bot_right]
  Inf_binary ~> Inf_insert, Inf_empty, and inf_top_right
  Sup_binary ~> Sup_insert, Sup_empty, and sup_bot_right
  Int_eq_Inter ~> Inf_insert, Inf_empty, and inf_top_right
  Un_eq_Union ~> Sup_insert, Sup_empty, and sup_bot_right
  Inter_def ~> INF_def, image_def
  Union_def ~> SUP_def, image_def
  INT_eq ~> INF_def, and image_def
  UN_eq ~> SUP_def, and image_def
  INF_subset ~> INF_superset_mono [OF _ order_refl]

More consistent and comprehensive names:

  INTER_eq_Inter_image ~> INF_def
  UNION_eq_Union_image ~> SUP_def
  INFI_def ~> INF_def
  SUPR_def ~> SUP_def
  INF_leI ~> INF_lower
  INF_leI2 ~> INF_lower2
  le_INFI ~> INF_greatest
  le_SUPI ~> SUP_upper
  le_SUPI2 ~> SUP_upper2
  SUP_leI ~> SUP_least
  INFI_bool_eq ~> INF_bool_eq
  SUPR_bool_eq ~> SUP_bool_eq
  INFI_apply ~> INF_apply
  SUPR_apply ~> SUP_apply
  INTER_def ~> INTER_eq
  UNION_def ~> UNION_eq


* Renamed theory Complete_Lattice to Complete_Lattices.

* Theory Complete_Lattices: lemmas Inf_eq_top_iff, INF_eq_top_iff,
INF_image, Inf_insert, INF_top, Inf_top_conv, INF_top_conv, SUP_bot,
Sup_bot_conv, SUP_bot_conv, Sup_eq_top_iff, SUP_eq_top_iff, SUP_image,
Sup_insert are now declared as [simp].  INCOMPATIBILITY.

* Theory Lattice: lemmas compl_inf_bot, compl_le_comp_iff,
compl_sup_top, inf_idem, inf_left_idem, inf_sup_absorb, sup_idem,
sup_inf_absob, sup_left_idem are now declared as [simp].  Minor

* Added syntactic classes "inf" and "sup" for the respective
constants.  INCOMPATIBILITY: Changes in the argument order of the
(mostly internal) locale predicates for some derived classes.

* Theorem collections ball_simps and bex_simps do not contain theorems
referring to UNION any longer; these have been moved to collection
UN_ball_bex_simps.  INCOMPATIBILITY.

* Theory Archimedean_Field: floor now is defined as parameter of a
separate type class floor_ceiling.

* Theory Finite_Set: more coherent development of fold_set locales:

    locale fun_left_comm ~> locale comp_fun_commute
    locale fun_left_comm_idem ~> locale comp_fun_idem

Both use point-free characterization; interpretation proofs may need

* Theory Limits: Type "'a net" has been renamed to "'a filter", in
accordance with standard mathematical terminology. INCOMPATIBILITY.

* Theory Complex_Main: The locale interpretations for the
bounded_linear and bounded_bilinear locales have been removed, in
order to reduce the number of duplicate lemmas. Users must use the
original names for distributivity theorems, potential INCOMPATIBILITY.

  divide.add ~> add_divide_distrib
  divide.diff ~> diff_divide_distrib
  divide.setsum ~> setsum_divide_distrib
  mult.add_right ~> right_distrib
  mult.diff_right ~> right_diff_distrib
  mult_right.setsum ~> setsum_right_distrib
  mult_left.diff ~> left_diff_distrib

* Theory Complex_Main: Several redundant theorems have been removed or
replaced by more general versions. INCOMPATIBILITY.

  real_diff_def ~> minus_real_def
  real_divide_def ~> divide_real_def
  real_less_def ~> less_le
  real_abs_def ~> abs_real_def
  real_sgn_def ~> sgn_real_def
  real_mult_commute ~> mult_commute
  real_mult_assoc ~> mult_assoc
  real_mult_1 ~> mult_1_left
  real_add_mult_distrib ~> left_distrib
  real_zero_not_eq_one ~> zero_neq_one
  real_mult_inverse_left ~> left_inverse
  INVERSE_ZERO ~> inverse_zero
  real_le_refl ~> order_refl
  real_le_antisym ~> order_antisym
  real_le_trans ~> order_trans
  real_le_linear ~> linear
  real_le_eq_diff ~> le_iff_diff_le_0
  real_add_left_mono ~> add_left_mono
  real_mult_order ~> mult_pos_pos
  real_mult_less_mono2 ~> mult_strict_left_mono
  real_of_int_real_of_nat ~> real_of_int_of_nat_eq
  real_0_le_divide_iff ~> zero_le_divide_iff
  realpow_two_disj ~> power2_eq_iff
  real_squared_diff_one_factored ~> square_diff_one_factored
  realpow_two_diff ~> square_diff_square_factored
  reals_complete2 ~> complete_real
  real_sum_squared_expand ~> power2_sum
  exp_ln_eq ~> ln_unique
  expi_add ~> exp_add
  expi_zero ~> exp_zero
  lemma_DERIV_subst ~> DERIV_cong
  LIMSEQ_Zfun_iff ~> tendsto_Zfun_iff
  LIMSEQ_const ~> tendsto_const
  LIMSEQ_norm ~> tendsto_norm
  LIMSEQ_add ~> tendsto_add
  LIMSEQ_minus ~> tendsto_minus
  LIMSEQ_minus_cancel ~> tendsto_minus_cancel
  LIMSEQ_diff ~> tendsto_diff
  bounded_linear.LIMSEQ ~> bounded_linear.tendsto
  bounded_bilinear.LIMSEQ ~> bounded_bilinear.tendsto
  LIMSEQ_mult ~> tendsto_mult
  LIMSEQ_inverse ~> tendsto_inverse
  LIMSEQ_divide ~> tendsto_divide
  LIMSEQ_pow ~> tendsto_power
  LIMSEQ_setsum ~> tendsto_setsum
  LIMSEQ_setprod ~> tendsto_setprod
  LIMSEQ_norm_zero ~> tendsto_norm_zero_iff
  LIMSEQ_rabs_zero ~> tendsto_rabs_zero_iff
  LIMSEQ_imp_rabs ~> tendsto_rabs
  LIMSEQ_add_minus ~> tendsto_add [OF _ tendsto_minus]
  LIMSEQ_add_const ~> tendsto_add [OF _ tendsto_const]
  LIMSEQ_diff_const ~> tendsto_diff [OF _ tendsto_const]
  LIMSEQ_Complex ~> tendsto_Complex
  LIM_ident ~> tendsto_ident_at
  LIM_const ~> tendsto_const
  LIM_add ~> tendsto_add
  LIM_add_zero ~> tendsto_add_zero
  LIM_minus ~> tendsto_minus
  LIM_diff ~> tendsto_diff
  LIM_norm ~> tendsto_norm
  LIM_norm_zero ~> tendsto_norm_zero
  LIM_norm_zero_cancel ~> tendsto_norm_zero_cancel
  LIM_norm_zero_iff ~> tendsto_norm_zero_iff
  LIM_rabs ~> tendsto_rabs
  LIM_rabs_zero ~> tendsto_rabs_zero
  LIM_rabs_zero_cancel ~> tendsto_rabs_zero_cancel
  LIM_rabs_zero_iff ~> tendsto_rabs_zero_iff
  LIM_compose ~> tendsto_compose
  LIM_mult ~> tendsto_mult
  LIM_scaleR ~> tendsto_scaleR
  LIM_of_real ~> tendsto_of_real
  LIM_power ~> tendsto_power
  LIM_inverse ~> tendsto_inverse
  LIM_sgn ~> tendsto_sgn
  isCont_LIM_compose ~> isCont_tendsto_compose
  bounded_linear.LIM ~> bounded_linear.tendsto
  bounded_linear.LIM_zero ~> bounded_linear.tendsto_zero
  bounded_bilinear.LIM ~> bounded_bilinear.tendsto
  bounded_bilinear.LIM_prod_zero ~> bounded_bilinear.tendsto_zero
  bounded_bilinear.LIM_left_zero ~> bounded_bilinear.tendsto_left_zero
  bounded_bilinear.LIM_right_zero ~> bounded_bilinear.tendsto_right_zero
  LIM_inverse_fun ~> tendsto_inverse [OF tendsto_ident_at]

* Theory Complex_Main: The definition of infinite series was
generalized.  Now it is defined on the type class {topological_space,
comm_monoid_add}.  Hence it is useable also for extended real numbers.

* Theory Complex_Main: The complex exponential function "expi" is now
a type-constrained abbreviation for "exp :: complex => complex"; thus
several polymorphic lemmas about "exp" are now applicable to "expi".

* Code generation:

  - Theory Library/Code_Char_ord provides native ordering of
    characters in the target language.

  - Commands code_module and code_library are legacy, use export_code

  - Method "evaluation" is legacy, use method "eval" instead.

  - Legacy evaluator "SML" is deactivated by default.  May be
    reactivated by the following theory command:

      setup {* Value.add_evaluator ("SML", Codegen.eval_term) *}

* Declare ext [intro] by default.  Rare INCOMPATIBILITY.

* New proof method "induction" that gives induction hypotheses the
name "IH", thus distinguishing them from further hypotheses that come
from rule induction.  The latter are still called "hyps".  Method
"induction" is a thin wrapper around "induct" and follows the same

* Method "fastsimp" has been renamed to "fastforce", but "fastsimp" is
still available as a legacy feature for some time.

* Nitpick:
  - Added "need" and "total_consts" options.
  - Reintroduced "show_skolems" option by popular demand.
  - Renamed attribute: nitpick_def ~> nitpick_unfold.

* Sledgehammer:
  - Use quasi-sound (and efficient) translations by default.
  - Added support for the following provers: E-ToFoF, LEO-II,
    Satallax, SNARK, Waldmeister, and Z3 with TPTP syntax.
  - Automatically preplay and minimize proofs before showing them if
    this can be done within reasonable time.
  - sledgehammer available_provers ~> sledgehammer supported_provers.
  - Added "preplay_timeout", "slicing", "type_enc", "sound",
    "max_mono_iters", and "max_new_mono_instances" options.
  - Removed "explicit_apply" and "full_types" options as well as "Full
    Types" Proof General menu item. INCOMPATIBILITY.

* Metis:
  - Removed "metisF" -- use "metis" instead. INCOMPATIBILITY.
  - Obsoleted "metisFT" -- use "metis (full_types)" instead.

* Command 'try':
  - Renamed 'try_methods' and added "simp:", "intro:", "dest:", and
    "elim:" options. INCOMPATIBILITY.
  - Introduced 'try' that not only runs 'try_methods' but also
    'solve_direct', 'sledgehammer', 'quickcheck', and 'nitpick'.

* Quickcheck:
  - Added "eval" option to evaluate terms for the found counterexample
    (currently only supported by the default (exhaustive) tester).
  - Added post-processing of terms to obtain readable counterexamples
    (currently only supported by the default (exhaustive) tester).
  - New counterexample generator quickcheck[narrowing] enables
    narrowing-based testing.  Requires the Glasgow Haskell compiler
    with its installation location defined in the Isabelle settings
    environment as ISABELLE_GHC.
  - Removed quickcheck tester "SML" based on the SML code generator
    (formly in HOL/Library).

* Function package: discontinued option "tailrec".  INCOMPATIBILITY,
use 'partial_function' instead.

* Theory Library/Extended_Reals replaces now the positive extended
reals found in probability theory. This file is extended by

* Theory Library/Old_Recdef: old 'recdef' package has been moved here,
from where it must be imported explicitly if it is really required.

* Theory Library/Wfrec: well-founded recursion combinator "wfrec" has
been moved here.  INCOMPATIBILITY.

* Theory Library/Saturated provides type of numbers with saturated

* Theory Library/Product_Lattice defines a pointwise ordering for the
product type 'a * 'b, and provides instance proofs for various order
and lattice type classes.

* Theory Library/Countable now provides the "countable_datatype" proof
method for proving "countable" class instances for datatypes.

* Theory Library/Cset_Monad allows do notation for computable sets
(cset) via the generic monad ad-hoc overloading facility.

* Library: Theories of common data structures are split into theories
for implementation, an invariant-ensuring type, and connection to an
abstract type. INCOMPATIBILITY.

  - RBT is split into RBT and RBT_Mapping.
  - AssocList is split and renamed into AList and AList_Mapping.
  - DList is split into DList_Impl, DList, and DList_Cset.
  - Cset is split into Cset and List_Cset.

* Theory Library/Nat_Infinity has been renamed to
Library/Extended_Nat, with name changes of the following types and

  type inat   ~> type enat
  Fin         ~> enat
  Infty       ~> infinity (overloaded)
  iSuc        ~> eSuc
  the_Fin     ~> the_enat

Every theorem name containing "inat", "Fin", "Infty", or "iSuc" has
been renamed accordingly. INCOMPATIBILITY.

* Session Multivariate_Analysis: The euclidean_space type class now
fixes a constant "Basis :: 'a set" consisting of the standard
orthonormal basis for the type. Users now have the option of
quantifying over this set instead of using the "basis" function, e.g.
"ALL x:Basis. P x" vs "ALL i<DIM('a). P (basis i)".

* Session Multivariate_Analysis: Type "('a, 'b) cart" has been renamed
to "('a, 'b) vec" (the syntax "'a ^ 'b" remains unaffected). Constants
"Cart_nth" and "Cart_lambda" have been respectively renamed to
"vec_nth" and "vec_lambda"; theorems mentioning those names have
changed to match. Definition theorems for overloaded constants now use
the standard "foo_vec_def" naming scheme. A few other theorems have
been renamed as follows (INCOMPATIBILITY):

  Cart_eq          ~> vec_eq_iff
  dist_nth_le_cart ~> dist_vec_nth_le
  tendsto_vector   ~> vec_tendstoI
  Cauchy_vector    ~> vec_CauchyI

* Session Multivariate_Analysis: Several duplicate theorems have been
removed, and other theorems have been renamed or replaced with more
general versions. INCOMPATIBILITY.

  finite_choice ~> finite_set_choice
  eventually_conjI ~> eventually_conj
  eventually_and ~> eventually_conj_iff
  eventually_false ~> eventually_False
  setsum_norm ~> norm_setsum
  Lim_sequentially ~> LIMSEQ_def
  Lim_ident_at ~> LIM_ident
  Lim_const ~> tendsto_const
  Lim_cmul ~> tendsto_scaleR [OF tendsto_const]
  Lim_neg ~> tendsto_minus
  Lim_add ~> tendsto_add
  Lim_sub ~> tendsto_diff
  Lim_mul ~> tendsto_scaleR
  Lim_vmul ~> tendsto_scaleR [OF _ tendsto_const]
  Lim_null_norm ~> tendsto_norm_zero_iff [symmetric]
  Lim_linear ~> bounded_linear.tendsto
  Lim_component ~> tendsto_euclidean_component
  Lim_component_cart ~> tendsto_vec_nth
  Lim_inner ~> tendsto_inner [OF tendsto_const]
  dot_lsum ~> inner_setsum_left
  dot_rsum ~> inner_setsum_right
  continuous_cmul ~> continuous_scaleR [OF continuous_const]
  continuous_neg ~> continuous_minus
  continuous_sub ~> continuous_diff
  continuous_vmul ~> continuous_scaleR [OF _ continuous_const]
  continuous_mul ~> continuous_scaleR
  continuous_inv ~> continuous_inverse
  continuous_at_within_inv ~> continuous_at_within_inverse
  continuous_at_inv ~> continuous_at_inverse
  continuous_at_norm ~> continuous_norm [OF continuous_at_id]
  continuous_at_infnorm ~> continuous_infnorm [OF continuous_at_id]
  continuous_at_component ~> continuous_component [OF continuous_at_id]
  continuous_on_neg ~> continuous_on_minus
  continuous_on_sub ~> continuous_on_diff
  continuous_on_cmul ~> continuous_on_scaleR [OF continuous_on_const]
  continuous_on_vmul ~> continuous_on_scaleR [OF _ continuous_on_const]
  continuous_on_mul ~> continuous_on_scaleR
  continuous_on_mul_real ~> continuous_on_mult
  continuous_on_inner ~> continuous_on_inner [OF continuous_on_const]
  continuous_on_norm ~> continuous_on_norm [OF continuous_on_id]
  continuous_on_inverse ~> continuous_on_inv
  uniformly_continuous_on_neg ~> uniformly_continuous_on_minus
  uniformly_continuous_on_sub ~> uniformly_continuous_on_diff
  subset_interior ~> interior_mono
  subset_closure ~> closure_mono
  closure_univ ~> closure_UNIV
  real_arch_lt ~> reals_Archimedean2
  real_arch ~> reals_Archimedean3
  real_abs_norm ~> abs_norm_cancel
  real_abs_sub_norm ~> norm_triangle_ineq3
  norm_cauchy_schwarz_abs ~> Cauchy_Schwarz_ineq2

* Session HOL-Probability:
  - Caratheodory's extension lemma is now proved for ring_of_sets.
  - Infinite products of probability measures are now available.
  - Sigma closure is independent, if the generator is independent
  - Use extended reals instead of positive extended

* Session HOLCF: Discontinued legacy theorem names, INCOMPATIBILITY.

  expand_fun_below ~> fun_below_iff
  below_fun_ext ~> fun_belowI
  expand_cfun_eq ~> cfun_eq_iff
  ext_cfun ~> cfun_eqI
  expand_cfun_below ~> cfun_below_iff
  below_cfun_ext ~> cfun_belowI
  monofun_fun_fun ~> fun_belowD
  monofun_fun_arg ~> monofunE
  monofun_lub_fun ~> adm_monofun [THEN admD]
  cont_lub_fun ~> adm_cont [THEN admD]
  cont2cont_Rep_CFun ~> cont2cont_APP
  cont_Rep_CFun_app ~> cont_APP_app
  cont_Rep_CFun_app_app ~> cont_APP_app_app
  cont_cfun_fun ~> cont_Rep_cfun1 [THEN contE]
  cont_cfun_arg ~> cont_Rep_cfun2 [THEN contE]
  contlub_cfun ~> lub_APP [symmetric]
  contlub_LAM ~> lub_LAM [symmetric]
  thelubI ~> lub_eqI
  UU_I ~> bottomI
  lift_distinct1 ~> lift.distinct(1)
  lift_distinct2 ~> lift.distinct(2)
  Def_not_UU ~> lift.distinct(2)
  Def_inject ~> lift.inject
  below_UU_iff ~> below_bottom_iff
  eq_UU_iff ~> eq_bottom_iff

*** Document preparation ***

* Antiquotation @{rail} layouts railroad syntax diagrams, see also
isar-ref manual, both for description and actual application of the

* Antiquotation @{value} evaluates the given term and presents its

* Antiquotations: term style "isub" provides ad-hoc conversion of
variables x1, y23 into subscripted form x\<^isub>1,

* Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
(e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).

* Localized \isabellestyle switch can be used within blocks or groups
like this:

  \isabellestyle{it}  %preferred default
  {\isabellestylett @{text "typewriter stuff"}}

* Discontinued special treatment of hard tabulators.  Implicit
tab-width is now defined as 1.  Potential INCOMPATIBILITY for visual

*** ML ***

* The inner syntax of sort/type/term/prop supports inlined YXML
representations within quoted string tokens.  By encoding logical
entities via Term_XML (in ML or Scala) concrete syntax can be
bypassed, which is particularly useful for producing bits of text
under external program control.

* Antiquotations for ML and document preparation are managed as theory
data, which requires explicit setup.

* Isabelle_Process.is_active allows tools to check if the official
process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
(better known as Proof General).

* Structure Proof_Context follows standard naming scheme.  Old
ProofContext is still available for some time as legacy alias.

* Structure Timing provides various operations for timing; supersedes
former start_timing/end_timing etc.

* Path.print is the official way to show file-system paths to users
(including quotes etc.).

* Inner syntax: identifiers in parse trees of generic categories
"logic", "aprop", "idt" etc. carry position information (disguised as
type constraints).  Occasional INCOMPATIBILITY with non-compliant
translations that choke on unexpected type constraints.  Positions can
be stripped in ML translations via Syntax.strip_positions /
Syntax.strip_positions_ast, or via the syntax constant
"_strip_positions" within parse trees.  As last resort, positions can
be disabled via the configuration option Syntax.positions, which is
called "syntax_positions" in Isar attribute syntax.

* Discontinued special status of various ML structures that contribute
to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
refer directly to Ast.Constant, Lexicon.is_identifier,
Syntax_Trans.mk_binder_tr etc.

* Typed print translation: discontinued show_sorts argument, which is
already available via context of "advanced" translation.

* Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
goal states; body tactic needs to address all subgoals uniformly.

* Slightly more special eq_list/eq_set, with shortcut involving
pointer equality (assumes that eq relation is reflexive).

* Classical tactics use proper Proof.context instead of historic types
claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
operate directly on Proof.context.  Raw type claset retains its use as
snapshot of the classical context, which can be recovered via
(put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
INCOMPATIBILITY, classical tactics and derived proof methods require
proper Proof.context.

*** System ***

* Discontinued support for Poly/ML 5.2, which was the last version
without proper multithreading and TimeLimit implementation.

* Discontinued old lib/scripts/polyml-platform, which has been
obsolete since Isabelle2009-2.

* Various optional external tools are referenced more robustly and
uniformly by explicit Isabelle settings as follows:

  ISABELLE_YAP    (formerly EXEC_YAP)

Note that automated detection from the file-system or search path has
been discontinued.  INCOMPATIBILITY.

* Scala layer provides JVM method invocation service for static
methods of type (String)String, see Invoke_Scala.method in ML.  For

  Invoke_Scala.method "java.lang.System.getProperty" "java.home"

Together with YXML.string_of_body/parse_body and XML.Encode/Decode
this allows to pass structured values between ML and Scala.

* The IsabelleText fonts includes some further glyphs to support the
Prover IDE.  Potential INCOMPATIBILITY: users who happen to have
installed a local copy (which is normally *not* required) need to
delete or update it from ~~/lib/fonts/.

New in Isabelle2011 (January 2011)

*** General ***

* Experimental Prover IDE based on Isabelle/Scala and jEdit (see
src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
useful tooltips and hyperlinks produced from its static analysis.  The
bundled component provides an executable Isabelle tool that can be run
like this:

  Isabelle2011/bin/isabelle jedit

* Significantly improved Isabelle/Isar implementation manual.

* System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
(and thus refers to something like $HOME/.isabelle/Isabelle2011),
while the default heap location within that directory lacks that extra
suffix.  This isolates multiple Isabelle installations from each
other, avoiding problems with old settings in new versions.
INCOMPATIBILITY, need to copy/upgrade old user settings manually.

* Source files are always encoded as UTF-8, instead of old-fashioned
ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
the following package declarations:


* Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
a Unicode character is treated as a single symbol, not a sequence of
non-ASCII bytes as before.  Since Isabelle/ML string literals may
contain symbols without further backslash escapes, Unicode can now be
used here as well.  Recall that Symbol.explode in ML provides a
consistent view on symbols, while raw explode (or String.explode)
merely give a byte-oriented representation.

* Theory loader: source files are primarily located via the master
directory of each theory node (where the .thy file itself resides).
The global load path is still partially available as legacy feature.
Minor INCOMPATIBILITY due to subtle change in file lookup: use
explicit paths, relatively to the theory.

* Special treatment of ML file names has been discontinued.
Historically, optional extensions .ML or .sml were added on demand --
at the cost of clarity of file dependencies.  Recall that Isabelle/ML
files exclusively use the .ML extension.  Minor INCOMPATIBILITY.

* Various options that affect pretty printing etc. are now properly
handled within the context via configuration options, instead of
unsynchronized references or print modes.  There are both ML Config.T
entities and Isar declaration attributes to access these.

  ML (Config.T)                 Isar (attribute)

  eta_contract                  eta_contract
  show_brackets                 show_brackets
  show_sorts                    show_sorts
  show_types                    show_types
  show_question_marks           show_question_marks
  show_consts                   show_consts
  show_abbrevs                  show_abbrevs

  Syntax.ast_trace              syntax_ast_trace
  Syntax.ast_stat               syntax_ast_stat
  Syntax.ambiguity_level        syntax_ambiguity_level

  Goal_Display.goals_limit      goals_limit
  Goal_Display.show_main_goal   show_main_goal

  Method.rule_trace             rule_trace

  Thy_Output.display            thy_output_display
  Thy_Output.quotes             thy_output_quotes
  Thy_Output.indent             thy_output_indent
  Thy_Output.source             thy_output_source
  Thy_Output.break              thy_output_break

Note that corresponding "..._default" references in ML may only be
changed globally at the ROOT session setup, but *not* within a theory.
The option "show_abbrevs" supersedes the former print mode
"no_abbrevs" with inverted meaning.

* More systematic naming of some configuration options.

  trace_simp  ~>  simp_trace
  debug_simp  ~>  simp_debug

* Support for real valued configuration options, using simplistic
floating-point notation that coincides with the inner syntax for

* Support for real valued preferences (with approximative PGIP type):
front-ends need to accept "pgint" values in float notation.

* The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
DejaVu Sans.

* Discontinued support for Poly/ML 5.0 and 5.1 versions.

*** Pure ***

* Command 'type_synonym' (with single argument) replaces somewhat
outdated 'types', which is still available as legacy feature for some

* Command 'nonterminal' (with 'and' separated list of arguments)
replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.

* Command 'notepad' replaces former 'example_proof' for
experimentation in Isar without any result.  INCOMPATIBILITY.

* Locale interpretation commands 'interpret' and 'sublocale' accept
lists of equations to map definitions in a locale to appropriate
entities in the context of the interpretation.  The 'interpretation'
command already provided this functionality.

* Diagnostic command 'print_dependencies' prints the locale instances
that would be activated if the specified expression was interpreted in
the current context.  Variant "print_dependencies!" assumes a context
without interpretations.

* Diagnostic command 'print_interps' prints interpretations in proofs
in addition to interpretations in theories.

* Discontinued obsolete 'global' and 'local' commands to manipulate
the theory name space.  Rare INCOMPATIBILITY.  The ML functions
Sign.root_path and Sign.local_path may be applied directly where this
feature is still required for historical reasons.

* Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
'definition' instead.

* The "prems" fact, which refers to the accidental collection of
foundational premises in the context, is now explicitly marked as
legacy feature and will be discontinued soon.  Consider using "assms"
of the head statement or reference facts by explicit names.

* Document antiquotations @{class} and @{type} print classes and type

* Document antiquotation @{file} checks file/directory entries within
the local file system.

*** HOL ***

* Coercive subtyping: functions can be declared as coercions and type
inference will add them as necessary upon input of a term.  Theory
Complex_Main declares real :: nat => real and real :: int => real as
coercions. A coercion function f is declared like this:

  declare [[coercion f]]

To lift coercions through type constructors (e.g. from nat => real to
nat list => real list), map functions can be declared, e.g.

  declare [[coercion_map map]]

Currently coercion inference is activated only in theories including
real numbers, i.e. descendants of Complex_Main.  This is controlled by
the configuration option "coercion_enabled", e.g. it can be enabled in
other theories like this:

  declare [[coercion_enabled]]

* Command 'partial_function' provides basic support for recursive
function definitions over complete partial orders.  Concrete instances
are provided for i) the option type, ii) tail recursion on arbitrary
types, and iii) the heap monad of Imperative_HOL.  See
src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
for examples.

* Function package: f.psimps rules are no longer implicitly declared

* Datatype package: theorems generated for executable equality (class
"eq") carry proper names and are treated as default code equations.

* Inductive package: now offers command 'inductive_simps' to
automatically derive instantiated and simplified equations for
inductive predicates, similar to 'inductive_cases'.

* Command 'enriched_type' allows to register properties of the
functorial structure of types.

* Improved infrastructure for term evaluation using code generator
techniques, in particular static evaluation conversions.

* Code generator: Scala (2.8 or higher) has been added to the target

* Code generator: globbing constant expressions "*" and "Theory.*"
have been replaced by the more idiomatic "_" and "Theory._".

* Code generator: export_code without explicit file declaration prints
to standard output.  INCOMPATIBILITY.

* Code generator: do not print function definitions for case
combinators any longer.

* Code generator: simplification with rules determined with
src/Tools/Code/code_simp.ML and method "code_simp".

* Code generator for records: more idiomatic representation of record
types.  Warning: records are not covered by ancient SML code
generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
rep_datatype declaration helps to succeed then:

  record 'a foo = ...
  rep_datatype foo_ext ...

* Records: logical foundation type for records does not carry a
'_type' suffix any longer (obsolete due to authentic syntax).

* Quickcheck now by default uses exhaustive testing instead of random
testing.  Random testing can be invoked by "quickcheck [random]",
exhaustive testing by "quickcheck [exhaustive]".

* Quickcheck instantiates polymorphic types with small finite
datatypes by default. This enables a simple execution mechanism to
handle quantifiers and function equality over the finite datatypes.

* Quickcheck random generator has been renamed from "code" to

* Quickcheck now has a configurable time limit which is set to 30
seconds by default. This can be changed by adding [timeout = n] to the
quickcheck command. The time limit for Auto Quickcheck is still set

* Quickcheck in locales considers interpretations of that locale for
counter example search.

* Sledgehammer:
  - Added "smt" and "remote_smt" provers based on the "smt" proof
    method. See the Sledgehammer manual for details ("isabelle doc
  - Renamed commands:
    sledgehammer atp_info ~> sledgehammer running_provers
    sledgehammer atp_kill ~> sledgehammer kill_provers
    sledgehammer available_atps ~> sledgehammer available_provers
  - Renamed options:
    sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
    sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
    sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
    (and "ms" and "min" are no longer supported)

* Nitpick:
  - Renamed options:
    nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
    nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
  - Added support for partial quotient types.
  - Added local versions of the "Nitpick.register_xxx" functions.
  - Added "whack" option.
  - Allow registration of quotient types as codatatypes.
  - Improved "merge_type_vars" option to merge more types.
  - Removed unsound "fast_descrs" option.
  - Added custom symmetry breaking for datatypes, making it possible to reach
    higher cardinalities.
  - Prevent the expansion of too large definitions.

* Proof methods "metis" and "meson" now have configuration options
"meson_trace", "metis_trace", and "metis_verbose" that can be enabled
to diagnose these tools. E.g.

    using [[metis_trace = true]]

* Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
manually as command 'solve_direct'.

* The default SMT solver Z3 must be enabled explicitly (due to
licensing issues) by setting the environment variable
Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
commercial applications, the SMT solver CVC3 is provided as fall-back;
changing the SMT solver is done via the configuration option

* Remote SMT solvers need to be referred to by the "remote_" prefix,
i.e. "remote_cvc3" and "remote_z3".

* Added basic SMT support for datatypes, records, and typedefs using
the oracle mode (no proofs).  Direct support of pairs has been dropped
in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
support for a similar behavior).  Minor INCOMPATIBILITY.

* Changed SMT configuration options:
  - Renamed:
    z3_proofs ~> smt_oracle (with inverted meaning)
    z3_trace_assms ~> smt_trace_used_facts
  - Added:

* Boogie output files (.b2i files) need to be declared in the theory

* Simplification procedure "list_to_set_comprehension" rewrites list
comprehensions applied to List.set to set comprehensions.  Occasional
INCOMPATIBILITY, may be deactivated like this:

  declare [[simproc del: list_to_set_comprehension]]

* Removed old version of primrec package.  INCOMPATIBILITY.

* Removed simplifier congruence rule of "prod_case", as has for long
been the case with "split".  INCOMPATIBILITY.

* String.literal is a type, but not a datatype.  INCOMPATIBILITY.

* Removed [split_format ... and ... and ...] version of
[split_format].  Potential INCOMPATIBILITY.

* Predicate "sorted" now defined inductively, with nice induction
rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.

* Constant "contents" renamed to "the_elem", to free the generic name
contents for other uses.  INCOMPATIBILITY.

* Renamed class eq and constant eq (for code generation) to class
equal and constant equal, plus renaming of related facts and various

* Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.

* Removed output syntax "'a ~=> 'b" for "'a => 'b option".

* Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
avoid confusion with finite sets.  INCOMPATIBILITY.

* Abandoned locales equiv, congruent and congruent2 for equivalence
relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
for congruent(2)).

* Some previously unqualified names have been qualified:

    bool ~> HOL.bool
    nat ~> Nat.nat

    Trueprop ~> HOL.Trueprop
    True ~> HOL.True
    False ~> HOL.False
    op & ~> HOL.conj
    op | ~> HOL.disj
    op --> ~> HOL.implies
    op = ~> HOL.eq
    Not ~> HOL.Not
    The ~> HOL.The
    All ~> HOL.All
    Ex ~> HOL.Ex
    Ex1 ~> HOL.Ex1
    Let ~> HOL.Let
    If ~> HOL.If
    Ball ~> Set.Ball
    Bex ~> Set.Bex
    Suc ~> Nat.Suc
    Pair ~> Product_Type.Pair
    fst ~> Product_Type.fst
    snd ~> Product_Type.snd
    curry ~> Product_Type.curry
    op : ~> Set.member
    Collect ~> Set.Collect


* More canonical naming convention for some fundamental definitions:

    bot_bool_eq ~> bot_bool_def
    top_bool_eq ~> top_bool_def
    inf_bool_eq ~> inf_bool_def
    sup_bool_eq ~> sup_bool_def
    bot_fun_eq  ~> bot_fun_def
    top_fun_eq  ~> top_fun_def
    inf_fun_eq  ~> inf_fun_def
    sup_fun_eq  ~> sup_fun_def


* More stylized fact names:

  expand_fun_eq ~> fun_eq_iff
  expand_set_eq ~> set_eq_iff
  set_ext       ~> set_eqI
  nat_number    ~> eval_nat_numeral


* Refactoring of code-generation specific operations in theory List:

    null ~> List.null

    mem_iff ~> member_def
    null_empty ~> null_def

INCOMPATIBILITY.  Note that these were not supposed to be used
regularly unless for striking reasons; their main purpose was code

Various operations from the Haskell prelude are used for generating
Haskell code.

* Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
"surj f" is now an abbreviation of "range f = UNIV".  The theorems
bij_def and surj_def are unchanged.  INCOMPATIBILITY.

* Abolished some non-alphabetic type names: "prod" and "sum" replace
"*" and "+" respectively.  INCOMPATIBILITY.

* Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
"Sum_Type.Plus" instead.

* Constant "split" has been merged with constant "prod_case"; names of
ML functions, facts etc. involving split have been retained so far,

* Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"

* Removed lemma "Option.is_none_none" which duplicates "is_none_def".

* Former theory Library/Enum is now part of the HOL-Main image.
INCOMPATIBILITY: all constants of the Enum theory now have to be
referred to by its qualified name.

  enum    ~>  Enum.enum
  nlists  ~>  Enum.nlists
  product ~>  Enum.product

* Theory Library/Monad_Syntax provides do-syntax for monad types.
Syntax in Library/State_Monad has been changed to avoid ambiguities.

* Theory Library/SetsAndFunctions has been split into
Library/Function_Algebras and Library/Set_Algebras; canonical names
for instance definitions for functions; various improvements.

* Theory Library/Multiset provides stable quicksort implementation of

* Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.

* Session Multivariate_Analysis: introduced a type class for euclidean
space.  Most theorems are now stated in terms of euclidean spaces
instead of finite cartesian products.

    real ^ 'n ~>  'a::real_vector
              ~>  'a::euclidean_space
              ~>  'a::ordered_euclidean_space
        (depends on your needs)

     _ $ _        ~> _ $$ _
     \<chi> x. _  ~> \<chi>\<chi> x. _
     CARD('n)     ~> DIM('a)

Also note that the indices are now natural numbers and not from some
finite type. Finite cartesian products of euclidean spaces, products
of euclidean spaces the real and complex numbers are instantiated to
be euclidean_spaces.  INCOMPATIBILITY.

* Session Probability: introduced pextreal as positive extended real
numbers.  Use pextreal as value for measures.  Introduce the
Radon-Nikodym derivative, product spaces and Fubini's theorem for
arbitrary sigma finite measures.  Introduces Lebesgue measure based on
the integral in Multivariate Analysis.  INCOMPATIBILITY.

* Session Imperative_HOL: revamped, corrected dozens of inadequacies.

* Session SPARK (with image HOL-SPARK) provides commands to load and
prove verification conditions generated by the SPARK Ada program
verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.

*** HOL-Algebra ***

* Theorems for additive ring operations (locale abelian_monoid and
descendants) are generated by interpretation from their multiplicative
counterparts.  Names (in particular theorem names) have the mandatory
qualifier 'add'.  Previous theorem names are redeclared for

* Structure "int_ring" is now an abbreviation (previously a
definition).  This fits more natural with advanced interpretations.

*** HOLCF ***

* The domain package now runs in definitional mode by default: The
former command 'new_domain' is now called 'domain'.  To use the domain
package in its original axiomatic mode, use 'domain (unsafe)'.

* The new class "domain" is now the default sort.  Class "predomain"
is an unpointed version of "domain". Theories can be updated by
replacing sort annotations as shown below.  INCOMPATIBILITY.

  'a::type ~> 'a::countable
  'a::cpo  ~> 'a::predomain
  'a::pcpo ~> 'a::domain

* The old type class "rep" has been superseded by class "domain".
Accordingly, users of the definitional package must remove any
"default_sort rep" declarations.  INCOMPATIBILITY.

* The domain package (definitional mode) now supports unpointed
predomain argument types, as long as they are marked 'lazy'. (Strict
arguments must be in class "domain".) For example, the following
domain definition now works:

  domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")

* Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
instances for types from main HOL: bool, nat, int, char, 'a + 'b,
'a option, and 'a list.  Additionally, it configures fixrec and the
domain package to work with these types.  For example:

  fixrec isInl :: "('a + 'b) u -> tr"
    where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"

  domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")

* The "(permissive)" option of fixrec has been replaced with a
per-equation "(unchecked)" option. See
src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.

* The "bifinite" class no longer fixes a constant "approx"; the class
now just asserts that such a function exists.  INCOMPATIBILITY.

* Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
defines an embedding of type 'a defl into udom by default; instances
of "bifinite" and "domain" classes are available in

* The syntax "REP('a)" has been replaced with "DEFL('a)".

* The predicate "directed" has been removed.  INCOMPATIBILITY.

* The type class "finite_po" has been removed.  INCOMPATIBILITY.

* The function "cprod_map" has been renamed to "prod_map".

* The monadic bind operator on each powerdomain has new binder syntax
similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
"upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".

* The infix syntax for binary union on each powerdomain has changed
from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set

* The constant "UU" has been renamed to "bottom".  The syntax "UU" is
still supported as an input translation.

* Renamed some theorems (the original names are also still available).

  expand_fun_below   ~> fun_below_iff
  below_fun_ext      ~> fun_belowI
  expand_cfun_eq     ~> cfun_eq_iff
  ext_cfun           ~> cfun_eqI
  expand_cfun_below  ~> cfun_below_iff
  below_cfun_ext     ~> cfun_belowI
  cont2cont_Rep_CFun ~> cont2cont_APP

* The Abs and Rep functions for various types have changed names.
Related theorem names have also changed to match. INCOMPATIBILITY.

  Rep_CFun  ~> Rep_cfun
  Abs_CFun  ~> Abs_cfun
  Rep_Sprod ~> Rep_sprod
  Abs_Sprod ~> Abs_sprod
  Rep_Ssum  ~> Rep_ssum
  Abs_Ssum  ~> Abs_ssum

* Lemmas with names of the form *_defined_iff or *_strict_iff have
been renamed to *_bottom_iff.  INCOMPATIBILITY.

* Various changes to bisimulation/coinduction with domain package:

  - Definitions of "bisim" constants no longer mention definedness.
  - With mutual recursion, "bisim" predicate is now curried.
  - With mutual recursion, each type gets a separate coind theorem.
  - Variable names in bisim_def and coinduct rules have changed.


* Case combinators generated by the domain package for type "foo" are
now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.

* Several theorems have been renamed to more accurately reflect the
names of constants and types involved.  INCOMPATIBILITY.

  thelub_const    ~> lub_const
  lub_const       ~> is_lub_const
  thelubI         ~> lub_eqI
  is_lub_lub      ~> is_lubD2
  lubI            ~> is_lub_lub
  unique_lub      ~> is_lub_unique
  is_ub_lub       ~> is_lub_rangeD1
  lub_bin_chain   ~> is_lub_bin_chain
  lub_fun         ~> is_lub_fun
  thelub_fun      ~> lub_fun
  thelub_cfun     ~> lub_cfun
  thelub_Pair     ~> lub_Pair
  lub_cprod       ~> is_lub_prod
  thelub_cprod    ~> lub_prod
  minimal_cprod   ~> minimal_prod
  inst_cprod_pcpo ~> inst_prod_pcpo
  UU_I            ~> bottomI
  compact_UU      ~> compact_bottom
  deflation_UU    ~> deflation_bottom
  finite_deflation_UU ~> finite_deflation_bottom

* Many legacy theorem names have been discontinued.  INCOMPATIBILITY.

  sq_ord_less_eq_trans ~> below_eq_trans
  sq_ord_eq_less_trans ~> eq_below_trans
  refl_less            ~> below_refl
  trans_less           ~> below_trans
  antisym_less         ~> below_antisym
  antisym_less_inverse ~> po_eq_conv [THEN iffD1]
  box_less             ~> box_below
  rev_trans_less       ~> rev_below_trans
  not_less2not_eq      ~> not_below2not_eq
  less_UU_iff          ~> below_UU_iff
  flat_less_iff        ~> flat_below_iff
  adm_less             ~> adm_below
  adm_not_less         ~> adm_not_below
  adm_compact_not_less ~> adm_compact_not_below
  less_fun_def         ~> below_fun_def
  expand_fun_less      ~> fun_below_iff
  less_fun_ext         ~> fun_belowI
  less_discr_def       ~> below_discr_def
  discr_less_eq        ~> discr_below_eq
  less_unit_def        ~> below_unit_def
  less_cprod_def       ~> below_prod_def
  prod_lessI           ~> prod_belowI
  Pair_less_iff        ~> Pair_below_iff
  fst_less_iff         ~> fst_below_iff
  snd_less_iff         ~> snd_below_iff
  expand_cfun_less     ~> cfun_below_iff
  less_cfun_ext        ~> cfun_belowI
  injection_less       ~> injection_below
  less_up_def          ~> below_up_def
  not_Iup_less         ~> not_Iup_below
  Iup_less             ~> Iup_below
  up_less              ~> up_below
  Def_inject_less_eq   ~> Def_below_Def
  Def_less_is_eq       ~> Def_below_iff
  spair_less_iff       ~> spair_below_iff
  less_sprod           ~> below_sprod
  spair_less           ~> spair_below
  sfst_less_iff        ~> sfst_below_iff
  ssnd_less_iff        ~> ssnd_below_iff
  fix_least_less       ~> fix_least_below
  dist_less_one        ~> dist_below_one
  less_ONE             ~> below_ONE
  ONE_less_iff         ~> ONE_below_iff
  less_sinlD           ~> below_sinlD
  less_sinrD           ~> below_sinrD

*** FOL and ZF ***

* All constant names are now qualified internally and use proper
identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.

*** ML ***

* Antiquotation @{assert} inlines a function bool -> unit that raises
Fail if the argument is false.  Due to inlining the source position of
failed assertions is included in the error output.

* Discontinued antiquotation @{theory_ref}, which is obsolete since ML
text is in practice always evaluated with a stable theory checkpoint.
Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.

* Antiquotation @{theory A} refers to theory A from the ancestry of
the current context, not any accidental theory loader state as before.
Potential INCOMPATIBILITY, subtle change in semantics.

* Syntax.pretty_priority (default 0) configures the required priority
of pretty-printed output and thus affects insertion of parentheses.

* Syntax.default_root (default "any") configures the inner syntax
category (nonterminal symbol) for parsing of terms.

* Former exception Library.UnequalLengths now coincides with

* Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
main functionality is provided by structure Simplifier.

* Renamed raw "explode" function to "raw_explode" to emphasize its
meaning.  Note that internally to Isabelle, Symbol.explode is used in
almost all situations.

* Discontinued obsolete function sys_error and exception SYS_ERROR.
See implementation manual for further details on exceptions in

* Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its

* Renamed structure PureThy to Pure_Thy and moved most of its
operations to structure Global_Theory, to emphasize that this is
rarely-used global-only stuff.

* Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
instead (or tracing for high-volume output).

* Configuration option show_question_marks only affects regular pretty
printing of types and terms, not raw Term.string_of_vname.

* ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
INCOMPATIBILITY, superseded by static antiquotations @{thm} and
@{thms} for most purposes.

* ML structure Unsynchronized is never opened, not even in Isar
interaction mode as before.  Old Unsynchronized.set etc. have been
discontinued -- use plain := instead.  This should be *rare* anyway,
since modern tools always work via official context data, notably
configuration options.

* Parallel and asynchronous execution requires special care concerning
interrupts.  Structure Exn provides some convenience functions that
avoid working directly with raw Interrupt.  User code must not absorb
interrupts -- intermediate handling (for cleanup etc.) needs to be
followed by re-raising of the original exception.  Another common
source of mistakes are "handle _" patterns, which make the meaning of
the program subject to physical effects of the environment.

New in Isabelle2009-2 (June 2010)

*** General ***

* Authentic syntax for *all* logical entities (type classes, type
constructors, term constants): provides simple and robust
correspondence between formal entities and concrete syntax.  Within
the parse tree / AST representations, "constants" are decorated by
their category (class, type, const) and spelled out explicitly with
their full internal name.

Substantial INCOMPATIBILITY concerning low-level syntax declarations
and translations (translation rules and translation functions in ML).
Some hints on upgrading:

  - Many existing uses of 'syntax' and 'translations' can be replaced
    by more modern 'type_notation', 'notation' and 'abbreviation',
    which are independent of this issue.

  - 'translations' require markup within the AST; the term syntax
    provides the following special forms:

      CONST c   -- produces syntax version of constant c from context
      XCONST c  -- literally c, checked as constant from context
      c         -- literally c, if declared by 'syntax'

    Plain identifiers are treated as AST variables -- occasionally the
    system indicates accidental variables via the error "rhs contains
    extra variables".

    Type classes and type constructors are marked according to their
    concrete syntax.  Some old translations rules need to be written
    for the "type" category, using type constructor application
    instead of pseudo-term application of the default category

  - 'parse_translation' etc. in ML may use the following

      @{class_syntax c}   -- type class c within parse tree / AST
      @{term_syntax c}    -- type constructor c within parse tree / AST
      @{const_syntax c}   -- ML version of "CONST c" above
      @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)

  - Literal types within 'typed_print_translations', i.e. those *not*
    represented as pseudo-terms are represented verbatim.  Use @{class
    c} or @{type_name c} here instead of the above syntax

Note that old non-authentic syntax was based on unqualified base
names, so all of the above "constant" names would coincide.  Recall
that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
diagnose syntax problems.

* Type constructors admit general mixfix syntax, not just infix.

* Concrete syntax may be attached to local entities without a proof
body, too.  This works via regular mixfix annotations for 'fix',
'def', 'obtain' etc. or via the explicit 'write' command, which is
similar to the 'notation' command in theory specifications.

* Discontinued unnamed infix syntax (legacy feature for many years) --
need to specify constant name and syntax separately.  Internal ML
datatype constructors have been renamed from InfixName to Infix etc.

* Schematic theorem statements need to be explicitly markup as such,
via commands 'schematic_lemma', 'schematic_theorem',
'schematic_corollary'.  Thus the relevance of the proof is made
syntactically clear, which impacts performance in a parallel or
asynchronous interactive environment.  Minor INCOMPATIBILITY.

* Use of cumulative prems via "!" in some proof methods has been
discontinued (old legacy feature).

* References 'trace_simp' and 'debug_simp' have been replaced by
configuration options stored in the context. Enabling tracing (the
case of debugging is similar) in proofs works via

  using [[trace_simp = true]]

Tracing is then active for all invocations of the simplifier in
subsequent goal refinement steps. Tracing may also still be enabled or
disabled via the ProofGeneral settings menu.

* Separate commands 'hide_class', 'hide_type', 'hide_const',
'hide_fact' replace the former 'hide' KIND command.  Minor

* Improved parallelism of proof term normalization: usedir -p2 -q0 is
more efficient than combinations with -q1 or -q2.

*** Pure ***

* Proofterms record type-class reasoning explicitly, using the
"unconstrain" operation internally.  This eliminates all sort
constraints from a theorem and proof, introducing explicit
OFCLASS-premises.  On the proof term level, this operation is
automatically applied at theorem boundaries, such that closed proofs
are always free of sort constraints.  INCOMPATIBILITY for tools that
inspect proof terms.

* Local theory specifications may depend on extra type variables that
are not present in the result type -- arguments TYPE('a) :: 'a itself
are added internally.  For example:

  definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"

* Predicates of locales introduced by classes carry a mandatory
"class" prefix.  INCOMPATIBILITY.

* Vacuous class specifications observe default sort.  INCOMPATIBILITY.

* Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
'class' instead.

* Command 'code_reflect' allows to incorporate generated ML code into
runtime environment; replaces immature code_datatype antiquotation.

* Code generator: simple concept for abstract datatypes obeying

* Code generator: details of internal data cache have no impact on the
user space functionality any longer.

* Methods "unfold_locales" and "intro_locales" ignore non-locale
subgoals.  This is more appropriate for interpretations with 'where'.

* Command 'example_proof' opens an empty proof body.  This allows to
experiment with Isar, without producing any persistent result.

* Commands 'type_notation' and 'no_type_notation' declare type syntax
within a local theory context, with explicit checking of the
constructors involved (in contrast to the raw 'syntax' versions).

* Commands 'types' and 'typedecl' now work within a local theory
context -- without introducing dependencies on parameters or
assumptions, which is not possible in Isabelle/Pure.

* Command 'defaultsort' has been renamed to 'default_sort', it works
within a local theory context.  Minor INCOMPATIBILITY.

*** HOL ***

* Command 'typedef' now works within a local theory context -- without
introducing dependencies on parameters or assumptions, which is not
possible in Isabelle/Pure/HOL.  Note that the logical environment may
contain multiple interpretations of local typedefs (with different
non-emptiness proofs), even in a global theory context.

* New package for quotient types.  Commands 'quotient_type' and
'quotient_definition' may be used for defining types and constants by
quotient constructions.  An example is the type of integers created by
quotienting pairs of natural numbers:

    intrel :: "(nat * nat) => (nat * nat) => bool"
    "intrel (x, y) (u, v) = (x + v = u + y)"

  quotient_type int = "nat * nat" / intrel
    by (auto simp add: equivp_def expand_fun_eq)

    "0::int" is "(0::nat, 0::nat)"

The method "lifting" can be used to lift of theorems from the
underlying "raw" type to the quotient type.  The example
src/HOL/Quotient_Examples/FSet.thy includes such a quotient
construction and provides a reasoning infrastructure for finite sets.

* Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
clash with new theory Quotient in Main HOL.

* Moved the SMT binding into the main HOL session, eliminating
separate HOL-SMT session.

* List membership infix mem operation is only an input abbreviation.

* Theory Library/Word.thy has been removed.  Use library Word/Word.thy
for future developements; former Library/Word.thy is still present in
the AFP entry RSAPPS.

* Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
longer shadowed.  INCOMPATIBILITY.

* Dropped theorem duplicate comp_arith; use semiring_norm instead.

* Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.

* Dropped normalizing_semiring etc; use the facts in semiring classes

* Dropped several real-specific versions of lemmas about floor and
ceiling; use the generic lemmas from theory "Archimedean_Field"

  floor_number_of_eq         ~> floor_number_of
  le_floor_eq_number_of      ~> number_of_le_floor
  le_floor_eq_zero           ~> zero_le_floor
  le_floor_eq_one            ~> one_le_floor
  floor_less_eq_number_of    ~> floor_less_number_of
  floor_less_eq_zero         ~> floor_less_zero
  floor_less_eq_one          ~> floor_less_one
  less_floor_eq_number_of    ~> number_of_less_floor
  less_floor_eq_zero         ~> zero_less_floor
  less_floor_eq_one          ~> one_less_floor
  floor_le_eq_number_of      ~> floor_le_number_of
  floor_le_eq_zero           ~> floor_le_zero
  floor_le_eq_one            ~> floor_le_one
  floor_subtract_number_of   ~> floor_diff_number_of
  floor_subtract_one         ~> floor_diff_one
  ceiling_number_of_eq       ~> ceiling_number_of
  ceiling_le_eq_number_of    ~> ceiling_le_number_of
  ceiling_le_zero_eq         ~> ceiling_le_zero
  ceiling_le_eq_one          ~> ceiling_le_one
  less_ceiling_eq_number_of  ~> number_of_less_ceiling
  less_ceiling_eq_zero       ~> zero_less_ceiling
  less_ceiling_eq_one        ~> one_less_ceiling
  ceiling_less_eq_number_of  ~> ceiling_less_number_of
  ceiling_less_eq_zero       ~> ceiling_less_zero
  ceiling_less_eq_one        ~> ceiling_less_one
  le_ceiling_eq_number_of    ~> number_of_le_ceiling
  le_ceiling_eq_zero         ~> zero_le_ceiling
  le_ceiling_eq_one          ~> one_le_ceiling
  ceiling_subtract_number_of ~> ceiling_diff_number_of
  ceiling_subtract_one       ~> ceiling_diff_one

* Theory "Finite_Set": various folding_XXX locales facilitate the
application of the various fold combinators on finite sets.

* Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
provides abstract red-black tree type which is backed by "RBT_Impl" as
implementation.  INCOMPATIBILITY.

* Theory Library/Coinductive_List has been removed -- superseded by

* Theory PReal, including the type "preal" and related operations, has
been removed.  INCOMPATIBILITY.

* Real: new development using Cauchy Sequences.

* Split off theory "Big_Operators" containing setsum, setprod,
Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.

* Theory "Rational" renamed to "Rat", for consistency with "Nat",

* Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.

* New set of rules "ac_simps" provides combined assoc / commute
rewrites for all interpretations of the appropriate generic locales.

* Renamed theory "OrderedGroup" to "Groups" and split theory
"Ring_and_Field" into theories "Rings" and "Fields"; for more
appropriate and more consistent names suitable for name prefixes
within the HOL theories.  INCOMPATIBILITY.

* Some generic constants have been put to appropriate theories:
  - less_eq, less: Orderings
  - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  - inverse, divide: Rings

* More consistent naming of type classes involving orderings (and

    lower_semilattice                   ~> semilattice_inf
    upper_semilattice                   ~> semilattice_sup

    dense_linear_order                  ~> dense_linorder

    pordered_ab_group_add               ~> ordered_ab_group_add
    pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
    pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
    pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
    pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
    pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
    pordered_cancel_semiring            ~> ordered_cancel_semiring
    pordered_comm_monoid_add            ~> ordered_comm_monoid_add
    pordered_comm_ring                  ~> ordered_comm_ring
    pordered_comm_semiring              ~> ordered_comm_semiring
    pordered_ring                       ~> ordered_ring
    pordered_ring_abs                   ~> ordered_ring_abs
    pordered_semiring                   ~> ordered_semiring

    ordered_ab_group_add                ~> linordered_ab_group_add
    ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
    ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
    ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
    ordered_field                       ~> linordered_field
    ordered_field_no_lb                 ~> linordered_field_no_lb
    ordered_field_no_ub                 ~> linordered_field_no_ub
    ordered_field_dense_linear_order    ~> dense_linordered_field
    ordered_idom                        ~> linordered_idom
    ordered_ring                        ~> linordered_ring
    ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
    ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
    ordered_ring_strict                 ~> linordered_ring_strict
    ordered_semidom                     ~> linordered_semidom
    ordered_semiring                    ~> linordered_semiring
    ordered_semiring_1                  ~> linordered_semiring_1
    ordered_semiring_1_strict           ~> linordered_semiring_1_strict
    ordered_semiring_strict             ~> linordered_semiring_strict

  The following slightly odd type classes have been moved to a
  separate theory Library/Lattice_Algebras:

    lordered_ab_group_add               ~> lattice_ab_group_add
    lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
    lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
    lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
    lordered_ring                       ~> lattice_ring


* Refined field classes:
  - classes division_ring_inverse_zero, field_inverse_zero,
    linordered_field_inverse_zero include rule inverse 0 = 0 --
    subsumes former division_by_zero class;
  - numerous lemmas have been ported from field to division_ring.

* Refined algebra theorem collections:
  - dropped theorem group group_simps, use algebra_simps instead;
  - dropped theorem group ring_simps, use field_simps instead;
  - proper theorem collection field_simps subsumes former theorem
    groups field_eq_simps and field_simps;
  - dropped lemma eq_minus_self_iff which is a duplicate for

* Theory Finite_Set and List: some lemmas have been generalized from
sets to lattices:

  fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  union_Union_fold_union        ~> sup_Sup_fold_sup
  Inter_fold_inter              ~> Inf_fold_inf
  Union_fold_union              ~> Sup_fold_sup
  inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  union_UNION_fold_union        ~> sup_SUPR_fold_sup
  INTER_fold_inter              ~> INFI_fold_inf
  UNION_fold_union              ~> SUPR_fold_sup

* Theory "Complete_Lattice": lemmas top_def and bot_def have been
replaced by the more convenient lemmas Inf_empty and Sup_empty.
Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.

* Reorganized theory Multiset: swapped notation of pointwise and
multiset order:

  - pointwise ordering is instance of class order with standard syntax
    <= and <;
  - multiset ordering has syntax <=# and <#; partial order properties
    are provided by means of interpretation with prefix
  - less duplication, less historical organization of sections,
    conversion from associations lists to multisets, rudimentary code
  - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
    if needed.


  multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  multi_count_ext  ~>  multiset_ext
  diff_union_inverse2  ~>  diff_union_cancelR


* Theory Permutation: replaced local "remove" by List.remove1.

* Code generation: ML and OCaml code is decorated with signatures.

* Theory List: added transpose.

* Library/Nat_Bijection.thy is a collection of bijective functions
between nat and other types, which supersedes the older libraries
Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.

  Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  Countable.pair_encode           ~> prod_encode
  NatIso.prod2nat                 ~> prod_encode
  NatIso.nat2prod                 ~> prod_decode
  NatIso.sum2nat                  ~> sum_encode
  NatIso.nat2sum                  ~> sum_decode
  NatIso.list2nat                 ~> list_encode
  NatIso.nat2list                 ~> list_decode
  NatIso.set2nat                  ~> set_encode
  NatIso.nat2set                  ~> set_decode

  Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode

* Sledgehammer:
  - Renamed ATP commands:
    atp_info     ~> sledgehammer running_atps
    atp_kill     ~> sledgehammer kill_atps
    atp_messages ~> sledgehammer messages
    atp_minimize ~> sledgehammer minimize
    print_atps   ~> sledgehammer available_atps
  - Added user's manual ("isabelle doc sledgehammer").
  - Added option syntax and "sledgehammer_params" to customize
    Sledgehammer's behavior.  See the manual for details.
  - Modified the Isar proof reconstruction code so that it produces
    direct proofs rather than proofs by contradiction.  (This feature
    is still experimental.)
  - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
    full-typed mode.
  - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.

* Nitpick:
  - Added and implemented "binary_ints" and "bits" options.
  - Added "std" option and implemented support for nonstandard models.
  - Added and implemented "finitize" option to improve the precision
    of infinite datatypes based on a monotonicity analysis.
  - Added support for quotient types.
  - Added support for "specification" and "ax_specification"
  - Added support for local definitions (for "function" and
    "termination" proofs).
  - Added support for term postprocessors.
  - Optimized "Multiset.multiset" and "FinFun.finfun".
  - Improved efficiency of "destroy_constrs" optimization.
  - Fixed soundness bugs related to "destroy_constrs" optimization and
    record getters.
  - Fixed soundness bug related to higher-order constructors.
  - Fixed soundness bug when "full_descrs" is enabled.
  - Improved precision of set constructs.
  - Added "atoms" option.
  - Added cache to speed up repeated Kodkod invocations on the same
  - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
    "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
    "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.

* Method "induct" now takes instantiations of the form t, where t is not
  a variable, as a shorthand for "x == t", where x is a fresh variable.
  If this is not intended, t has to be enclosed in parentheses.
  By default, the equalities generated by definitional instantiations
  are pre-simplified, which may cause parameters of inductive cases
  to disappear, or may even delete some of the inductive cases.
  Use "induct (no_simp)" instead of "induct" to restore the old
  behaviour. The (no_simp) option is also understood by the "cases"
  and "nominal_induct" methods, which now perform pre-simplification, too.

*** HOLCF ***

* Variable names in lemmas generated by the domain package have
changed; the naming scheme is now consistent with the HOL datatype
package.  Some proof scripts may be affected, INCOMPATIBILITY.

* The domain package no longer defines the function "foo_copy" for
recursive domain "foo".  The reach lemma is now stated directly in
terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
be reformulated in terms of "foo_take", INCOMPATIBILITY.

* Most definedness lemmas generated by the domain package (previously
of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
like "foo$x = UU <-> x = UU", which works better as a simp rule.
Proofs that used definedness lemmas as intro rules may break,

* Induction and casedist rules generated by the domain package now
declare proper case_names (one called "bottom", and one named for each
constructor).  INCOMPATIBILITY.

* For mutually-recursive domains, separate "reach" and "take_lemma"
rules are generated for each domain, INCOMPATIBILITY.

  foo_bar.reach       ~> foo.reach  bar.reach
  foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma

* Some lemmas generated by the domain package have been renamed for
consistency with the datatype package, INCOMPATIBILITY.

  foo.ind        ~> foo.induct
  foo.finite_ind ~> foo.finite_induct
  foo.coind      ~> foo.coinduct
  foo.casedist   ~> foo.exhaust
  foo.exhaust    ~> foo.nchotomy

* For consistency with other definition packages, the fixrec package
now generates qualified theorem names, INCOMPATIBILITY.

  foo_simps  ~> foo.simps
  foo_unfold ~> foo.unfold
  foo_induct ~> foo.induct

* The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
method and internal fixrec proofs now use the default simpset instead.

* The "contlub" predicate has been removed.  Proof scripts should use
lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.

* The "admw" predicate has been removed, INCOMPATIBILITY.

* The constants cpair, cfst, and csnd have been removed in favor of
Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.

*** ML ***

* Antiquotations for basic formal entities:

    @{class NAME}         -- type class
    @{class_syntax NAME}  -- syntax representation of the above

    @{type_name NAME}     -- logical type
    @{type_abbrev NAME}   -- type abbreviation
    @{nonterminal NAME}   -- type of concrete syntactic category
    @{type_syntax NAME}   -- syntax representation of any of the above

    @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
    @{const_abbrev NAME}  -- abbreviated constant
    @{const_syntax NAME}  -- syntax representation of any of the above

* Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
syntax constant (cf. 'syntax' command).

* Antiquotation @{make_string} inlines a function to print arbitrary
values similar to the ML toplevel.  The result is compiler dependent
and may fall back on "?" in certain situations.

* Diagnostic commands 'ML_val' and 'ML_command' may refer to
antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
Isar.state() and Isar.goal(), which belong to the old TTY loop and do
not work with the asynchronous Isar document model.

* Configuration options now admit dynamic default values, depending on
the context or even global references.

* SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
uses an efficient external library if available (for Poly/ML).

* Renamed some important ML structures, while keeping the old names
for some time as aliases within the structure Legacy:

  OuterKeyword  ~>  Keyword
  OuterLex      ~>  Token
  OuterParse    ~>  Parse
  OuterSyntax   ~>  Outer_Syntax
  PrintMode     ~>  Print_Mode
  SpecParse     ~>  Parse_Spec
  ThyInfo       ~>  Thy_Info
  ThyLoad       ~>  Thy_Load
  ThyOutput     ~>  Thy_Output
  TypeInfer     ~>  Type_Infer

Note that "open Legacy" simplifies porting of sources, but forgetting
to remove it again will complicate porting again in the future.

* Most operations that refer to a global context are named
accordingly, e.g. Simplifier.global_context or
ProofContext.init_global.  There are some situations where a global
context actually works, but under normal circumstances one needs to
pass the proper local context through the code!

* Discontinued old TheoryDataFun with its copy/init operation -- data
needs to be pure.  Functor Theory_Data_PP retains the traditional
Pretty.pp argument to merge, which is absent in the standard
Theory_Data version.

* Sorts.certify_sort and derived "cert" operations for types and terms
no longer minimize sorts.  Thus certification at the boundary of the
inference kernel becomes invariant under addition of class relations,
which is an important monotonicity principle.  Sorts are now minimized
in the syntax layer only, at the boundary between the end-user and the
system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
explicitly in rare situations.

* Renamed old-style Drule.standard to Drule.export_without_context, to
emphasize that this is in no way a standard operation.

* Subgoal.FOCUS (and variants): resulting goal state is normalized as
usual for resolution.  Rare INCOMPATIBILITY.

* Renamed varify/unvarify operations to varify_global/unvarify_global
to emphasize that these only work in a global situation (which is
quite rare).

* Curried take and drop in library.ML; negative length is interpreted
as infinity (as in chop).  Subtle INCOMPATIBILITY.

* Proof terms: type substitutions on proof constants now use canonical
order of type variables.  INCOMPATIBILITY for tools working with proof

* Raw axioms/defs may no longer carry sort constraints, and raw defs
may no longer carry premises.  User-level specifications are
transformed accordingly by Thm.add_axiom/add_def.

*** System ***

* Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
proof terms are enabled unconditionally in the new HOL-Proofs image.

* Discontinued old ISABELLE and ISATOOL environment settings (legacy
feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,

* Old lib/scripts/polyml-platform is superseded by the
ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
variant, even on a 64 bit machine.  The following example setting
prefers 64 bit if available:


* The preliminary Isabelle/jEdit application demonstrates the emerging
Isabelle/Scala layer for advanced prover interaction and integration.
See src/Tools/jEdit or "isabelle jedit" provided by the properly built

* "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
similar to the default assignment of the document preparation system
(cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
provides some operations for direct access to the font without asking
the user for manual installation.

New in Isabelle2009-1 (December 2009)

*** General ***

* Discontinued old form of "escaped symbols" such as \\<forall>.  Only
one backslash should be used, even in ML sources.

*** Pure ***

* Locale interpretation propagates mixins along the locale hierarchy.
The currently only available mixins are the equations used to map
local definitions to terms of the target domain of an interpretation.

* Reactivated diagnostic command 'print_interps'.  Use "print_interps
loc" to print all interpretations of locale "loc" in the theory.
Interpretations in proofs are not shown.

* Thoroughly revised locales tutorial.  New section on conditional

* On instantiation of classes, remaining undefined class parameters
are formally declared.  INCOMPATIBILITY.

*** Document preparation ***

* New generalized style concept for printing terms: @{foo (style) ...}
instead of @{foo_style style ...}  (old form is still retained for
backward compatibility).  Styles can be also applied for
antiquotations prop, term_type and typeof.

*** HOL ***

* New proof method "smt" for a combination of first-order logic with
equality, linear and nonlinear (natural/integer/real) arithmetic, and
fixed-size bitvectors; there is also basic support for higher-order
features (esp. lambda abstractions).  It is an incomplete decision
procedure based on external SMT solvers using the oracle mechanism;
for the SMT solver Z3, this method is proof-producing.  Certificates
are provided to avoid calling the external solvers solely for
re-checking proofs.  Due to a remote SMT service there is no need for
installing SMT solvers locally.  See src/HOL/SMT.

* New commands to load and prove verification conditions generated by
the Boogie program verifier or derived systems (e.g. the Verifying C
Compiler (VCC) or Spec#).  See src/HOL/Boogie.

* New counterexample generator tool 'nitpick' based on the Kodkod
relational model finder.  See src/HOL/Tools/Nitpick and

* New commands 'code_pred' and 'values' to invoke the predicate
compiler and to enumerate values of inductive predicates.

* A tabled implementation of the reflexive transitive closure.

* New implementation of quickcheck uses generic code generator;
default generators are provided for all suitable HOL types, records
and datatypes.  Old quickcheck can be re-activated importing theory

* New testing tool Mirabelle for automated proof tools.  Applies
several tools and tactics like sledgehammer, metis, or quickcheck, to
every proof step in a theory.  To be used in batch mode via the
"mirabelle" utility.

* New proof method "sos" (sum of squares) for nonlinear real
arithmetic (originally due to John Harison). It requires theory
Library/Sum_Of_Squares.  It is not a complete decision procedure but
works well in practice on quantifier-free real arithmetic with +, -,
*, ^, =, <= and <, i.e. boolean combinations of equalities and
inequalities between polynomials.  It makes use of external
semidefinite programming solvers.  Method "sos" generates a
certificate that can be pasted into the proof thus avoiding the need
to call an external tool every time the proof is checked.  See

* New method "linarith" invokes existing linear arithmetic decision
procedure only.

* New command 'atp_minimal' reduces result produced by Sledgehammer.

* New Sledgehammer option "Full Types" in Proof General settings menu.
Causes full type information to be output to the ATPs.  This slows
ATPs down considerably but eliminates a source of unsound "proofs"
that fail later.

* New method "metisFT": A version of metis that uses full type
information in order to avoid failures of proof reconstruction.

* New evaluator "approximate" approximates an real valued term using
the same method as the approximation method.

* Method "approximate" now supports arithmetic expressions as
boundaries of intervals and implements interval splitting and Taylor
series expansion.

* ML antiquotation @{code_datatype} inserts definition of a datatype
generated by the code generator; e.g. see src/HOL/Predicate.thy.

* New theory SupInf of the supremum and infimum operators for sets of

* New theory Probability, which contains a development of measure
theory, eventually leading to Lebesgue integration and probability.

* Extended Multivariate Analysis to include derivation and Brouwer's
fixpoint theorem.

* Reorganization of number theory, INCOMPATIBILITY:
  - new number theory development for nat and int, in theories Divides
    and GCD as well as in new session Number_Theory
  - some constants and facts now suffixed with _nat and _int
  - former session NumberTheory now named Old_Number_Theory, including
    theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  - moved theory Pocklington from src/HOL/Library to

* Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
lcm of finite and infinite sets. It is shown that they form a complete

* Class semiring_div requires superclass no_zero_divisors and proof of
div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
generalized to class semiring_div, subsuming former theorems
zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.

* Refinements to lattice classes and sets:
  - less default intro/elim rules in locale variant, more default
    intro/elim rules in class variant: more uniformity
  - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  - renamed ACI to inf_sup_aci
  - new class "boolean_algebra"
  - class "complete_lattice" moved to separate theory
    "Complete_Lattice"; corresponding constants (and abbreviations)
    renamed and with authentic syntax:
    Set.Inf ~>    Complete_Lattice.Inf
    Set.Sup ~>    Complete_Lattice.Sup
    Set.INFI ~>   Complete_Lattice.INFI
    Set.SUPR ~>   Complete_Lattice.SUPR
    Set.Inter ~>  Complete_Lattice.Inter
    Set.Union ~>  Complete_Lattice.Union
    Set.INTER ~>  Complete_Lattice.INTER
    Set.UNION ~>  Complete_Lattice.UNION
  - authentic syntax for
  - mere abbreviations:
    Set.empty               (for bot)
    Set.UNIV                (for top)
    Set.inter               (for inf, formerly Set.Int)
    Set.union               (for sup, formerly Set.Un)
    Complete_Lattice.Inter  (for Inf)
    Complete_Lattice.Union  (for Sup)
    Complete_Lattice.INTER  (for INFI)
    Complete_Lattice.UNION  (for SUPR)
  - object-logic definitions as far as appropriate

INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
Un_subset_iff are explicitly deleted as default simp rules; then also
their lattice counterparts le_inf_iff and le_sup_iff have to be
deleted to achieve the desired effect.

* Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
rules by default any longer; the same applies to min_max.inf_absorb1

* Rules sup_Int_eq and sup_Un_eq are no longer declared as
pred_set_conv by default.  INCOMPATIBILITY.

* Power operations on relations and functions are now one dedicated
constant "compow" with infix syntax "^^".  Power operation on
multiplicative monoids retains syntax "^" and is now defined generic
in class power.  INCOMPATIBILITY.

* Relation composition "R O S" now has a more standard argument order:
"R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
break, since the O_assoc rule was not rewritten like this.  Fix using
O_assoc[symmetric].  The same applies to the curried version "R OO S".

* Function "Inv" is renamed to "inv_into" and function "inv" is now an
abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.

* Most rules produced by inductive and datatype package have mandatory

* Changed "DERIV_intros" to a dynamic fact, which can be augmented by
the attribute of the same name.  Each of the theorems in the list
DERIV_intros assumes composition with an additional function and
matches a variable to the derivative, which has to be solved by the
Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
of most elementary terms.  Former Maclauren.DERIV_tac and
Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).

* Code generator attributes follow the usual underscore convention:
    code_unfold     replaces    code unfold
    code_post       replaces    code post

* Renamed methods:
    sizechange -> size_change
    induct_scheme -> induction_schema

* Discontinued abbreviation "arbitrary" of constant "undefined".
INCOMPATIBILITY, use "undefined" directly.

* Renamed theorems:
    Suc_eq_add_numeral_1 -> Suc_eq_plus1
    Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
    Suc_plus1 -> Suc_eq_plus1
    *anti_sym -> *antisym*
    vector_less_eq_def -> vector_le_def

* Added theorem List.map_map as [simp].  Removed List.map_compose.

* Removed predicate "M hassize n" (<--> card M = n & finite M).

*** HOLCF ***

* Theory Representable defines a class "rep" of domains that are
representable (via an ep-pair) in the universal domain type "udom".
Instances are provided for all type constructors defined in HOLCF.

* The 'new_domain' command is a purely definitional version of the
domain package, for representable domains.  Syntax is identical to the
old domain package.  The 'new_domain' package also supports indirect
recursion using previously-defined type constructors.  See
src/HOLCF/ex/New_Domain.thy for examples.

* Method "fixrec_simp" unfolds one step of a fixrec-defined constant
on the left-hand side of an equation, and then performs
simplification.  Rewriting is done using rules declared with the
"fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.

* The pattern-match compiler in 'fixrec' can now handle constructors
with HOL function types.  Pattern-match combinators for the Pair
constructor are pre-configured.

* The 'fixrec' package now produces better fixed-point induction rules
for mutually-recursive definitions:  Induction rules have conclusions
of the form "P foo bar" instead of "P <foo, bar>".

* The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
been renamed to "below".  The name "below" now replaces "less" in many
theorem names.  (Legacy theorem names using "less" are still supported
as well.)

* The 'fixrec' package now supports "bottom patterns".  Bottom
patterns can be used to generate strictness rules, or to make
functions more strict (much like the bang-patterns supported by the
Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for

*** ML ***

* Support for Poly/ML 5.3.0, with improved reporting of compiler
errors and run-time exceptions, including detailed source positions.

* Structure Name_Space (formerly NameSpace) now manages uniquely
identified entries, with some additional information such as source
position, logical grouping etc.

* Theory and context data is now introduced by the simplified and
modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
to be pure, but the old TheoryDataFun for mutable data (with explicit
copy operation) is still available for some time.

* Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
provides a high-level programming interface to synchronized state
variables with atomic update.  This works via pure function
application within a critical section -- its runtime should be as
short as possible; beware of deadlocks if critical code is nested,
either directly or indirectly via other synchronized variables!

* Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
wraps raw ML references, explicitly indicating their non-thread-safe
behaviour.  The Isar toplevel keeps this structure open, to
accommodate Proof General as well as quick and dirty interactive
experiments with references.

* PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
parallel tactical reasoning.

* Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
are similar to SUBPROOF, but are slightly more flexible: only the
specified parts of the subgoal are imported into the context, and the
body tactic may introduce new subgoals and schematic variables.

* Old tactical METAHYPS, which does not observe the proof context, has
been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
or Subgoal.FOCUS etc.

* Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
functors have their own ML name space there is no point to mark them
separately.)  Minor INCOMPATIBILITY.

* Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.

* Renamed several structures FooBar to Foo_Bar.  Occasional,

* Operations of structure Skip_Proof no longer require quick_and_dirty
mode, which avoids critical setmp.

* Eliminated old Attrib.add_attributes, Method.add_methods and related
combinators for "args".  INCOMPATIBILITY, need to use simplified
Attrib/Method.setup introduced in Isabelle2009.

* Proper context for simpset_of, claset_of, clasimpset_of.  May fall
back on global_simpset_of, global_claset_of, global_clasimpset_of as
last resort.  INCOMPATIBILITY.

* Display.pretty_thm now requires a proper context (cf. former
ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
or even Display.pretty_thm_without_context as last resort.

* Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
Syntax.pretty_typ/term directly, preferably with proper context
instead of global theory.

*** System ***

* Further fine tuning of parallel proof checking, scales up to 8 cores
(max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
usedir option -q.

* Support for additional "Isabelle components" via etc/components, see
also the system manual.

* The isabelle makeall tool now operates on all components with
IsaMakefile, not just hardwired "logics".

* Removed "compress" option from isabelle-process and isabelle usedir;
this is always enabled.

* Discontinued support for Poly/ML 4.x versions.

* Isabelle tool "wwwfind" provides web interface for 'find_theorems'
on a given logic image.  This requires the lighttpd webserver and is
currently supported on Linux only.

New in Isabelle2009 (April 2009)

*** General ***

* Simplified main Isabelle executables, with less surprises on
case-insensitive file-systems (such as Mac OS).

  - The main Isabelle tool wrapper is now called "isabelle" instead of

  - The former "isabelle" alias for "isabelle-process" has been
    removed (should rarely occur to regular users).

  - The former "isabelle-interface" and its alias "Isabelle" have been
    removed (interfaces are now regular Isabelle tools).

Within scripts and make files, the Isabelle environment variables
respectively.  (The latter are still available as legacy feature.)

The old isabelle-interface wrapper could react in confusing ways if
the interface was uninstalled or changed otherwise.  Individual
interface tool configuration is now more explicit, see also the
Isabelle system manual.  In particular, Proof General is now available
via "isabelle emacs".

INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
purge installed copies of Isabelle executables and re-run "isabelle
install -p ...", or use symlinks.

* The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
old ~/isabelle, which was slightly non-standard and apt to cause
surprises on case-insensitive file-systems (such as Mac OS).

INCOMPATIBILITY, need to move existing ~/isabelle/etc,
~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
care is required when using older releases of Isabelle.  Note that
ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
Isabelle distribution, in order to use the new ~/.isabelle uniformly.

* Proofs of fully specified statements are run in parallel on
multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
a regular 4-core machine, if the initial heap space is made reasonably
large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)

* The main reference manuals ("isar-ref", "implementation", and
"system") have been updated and extended.  Formally checked references
as hyperlinks are now available uniformly.

*** Pure ***

* Complete re-implementation of locales.  INCOMPATIBILITY in several
respects.  The most important changes are listed below.  See the
Tutorial on Locales ("locales" manual) for details.

- In locale expressions, instantiation replaces renaming.  Parameters
must be declared in a for clause.  To aid compatibility with previous
parameter inheritance, in locale declarations, parameters that are not
'touched' (instantiation position "_" or omitted) are implicitly added
with their syntax at the beginning of the for clause.

- Syntax from abbreviations and definitions in locales is available in
locale expressions and context elements.  The latter is particularly
useful in locale declarations.

- More flexible mechanisms to qualify names generated by locale
expressions.  Qualifiers (prefixes) may be specified in locale
expressions, and can be marked as mandatory (syntax: "name!:") or
optional (syntax "name?:").  The default depends for plain "name:"
depends on the situation where a locale expression is used: in
commands 'locale' and 'sublocale' prefixes are optional, in
'interpretation' and 'interpret' prefixes are mandatory.  The old
implicit qualifiers derived from the parameter names of a locale are
no longer generated.

- Command "sublocale l < e" replaces "interpretation l < e".  The
instantiation clause in "interpretation" and "interpret" (square
brackets) is no longer available.  Use locale expressions.

- When converting proof scripts, mandatory qualifiers in
'interpretation' and 'interpret' should be retained by default, even
if this is an INCOMPATIBILITY compared to former behavior.  In the
worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
in locale expressions range over a single locale instance only.

- Dropped locale element "includes".  This is a major INCOMPATIBILITY.
In existing theorem specifications replace the includes element by the
respective context elements of the included locale, omitting those
that are already present in the theorem specification.  Multiple
assume elements of a locale should be replaced by a single one
involving the locale predicate.  In the proof body, declarations (most
notably theorems) may be regained by interpreting the respective
locales in the proof context as required (command "interpret").

If using "includes" in replacement of a target solely because the
parameter types in the theorem are not as general as in the target,
consider declaring a new locale with additional type constraints on
the parameters (context element "constrains").

- Discontinued "locale (open)".  INCOMPATIBILITY.

- Locale interpretation commands no longer attempt to simplify goal.
INCOMPATIBILITY: in rare situations the generated goal differs.  Use
methods intro_locales and unfold_locales to clarify.

- Locale interpretation commands no longer accept interpretation

* Class declaration: so-called "base sort" must not be given in import
list any longer, but is inferred from the specification.  Particularly
in HOL, write

    class foo = ...

instead of

    class foo = type + ...

* Class target: global versions of theorems stemming do not carry a
parameter prefix any longer.  INCOMPATIBILITY.

* Class 'instance' command no longer accepts attached definitions.
INCOMPATIBILITY, use proper 'instantiation' target instead.

* Recovered hiding of consts, which was accidentally broken in
Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
makes c inaccessible; consider using ``hide (open) const c'' instead.

* Slightly more coherent Pure syntax, with updated documentation in
isar-ref manual.  Removed locales meta_term_syntax and
meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
INCOMPATIBILITY in rare situations.  Note that &&& should not be used
directly in regular applications.

* There is a new syntactic category "float_const" for signed decimal
fractions (e.g. 123.45 or -123.45).

* Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
interface with 'setup' command instead.

* Command 'local_setup' is similar to 'setup', but operates on a local
theory context.

* The 'axiomatization' command now only works within a global theory

* Goal-directed proof now enforces strict proof irrelevance wrt. sort
hypotheses.  Sorts required in the course of reasoning need to be
covered by the constraints in the initial statement, completed by the
type instance information of the background theory.  Non-trivial sort
hypotheses, which rarely occur in practice, may be specified via
vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:

  lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...

The result contains an implicit sort hypotheses as before --
SORT_CONSTRAINT premises are eliminated as part of the canonical rule

* Generalized Isar history, with support for linear undo, direct state
addressing etc.

* Changed defaults for unify configuration options:

  unify_trace_bound = 50 (formerly 25)
  unify_search_bound = 60 (formerly 30)

* Different bookkeeping for code equations (INCOMPATIBILITY):

  a) On theory merge, the last set of code equations for a particular
     constant is taken (in accordance with the policy applied by other
     parts of the code generator framework).

  b) Code equations stemming from explicit declarations (e.g. code
     attribute) gain priority over default code equations stemming
     from definition, primrec, fun etc.

* Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.

* Unified theorem tables for both code generators.  Thus [code
func] has disappeared and only [code] remains.  INCOMPATIBILITY.

* Command 'find_consts' searches for constants based on type and name
patterns, e.g.

    find_consts "_ => bool"

By default, matching is against subtypes, but it may be restricted to
the whole type.  Searching by name is possible.  Multiple queries are
conjunctive and queries may be negated by prefixing them with a

    find_consts strict: "_ => bool" name: "Int" -"int => int"

* New 'find_theorems' criterion "solves" matches theorems that
directly solve the current goal (modulo higher-order unification).

* Auto solve feature for main theorem statements: whenever a new goal
is stated, "find_theorems solves" is called; any theorems that could
solve the lemma directly are listed as part of the goal state.
Cf. associated options in Proof General Isabelle settings menu,
enabled by default, with reasonable timeout for pathological cases of
higher-order unification.

*** Document preparation ***

* Antiquotation @{lemma} now imitates a regular terminal proof,
demanding keyword 'by' and supporting the full method expression
syntax just like the Isar command 'by'.

*** HOL ***

* Integrated main parts of former image HOL-Complex with HOL.  Entry
points Main and Complex_Main remain as before.

* Logic image HOL-Plain provides a minimal HOL with the most important
tools available (inductive, datatype, primrec, ...).  This facilitates
experimentation and tool development.  Note that user applications
(and library theories) should never refer to anything below theory
Main, as before.

* Logic image HOL-Main stops at theory Main, and thus facilitates
experimentation due to shorter build times.

* Logic image HOL-NSA contains theories of nonstandard analysis which
were previously part of former HOL-Complex.  Entry point Hyperreal
remains valid, but theories formerly using Complex_Main should now use
new entry point Hypercomplex.

* Generic ATP manager for Sledgehammer, based on ML threads instead of
Posix processes.  Avoids potentially expensive forking of the ML
process.  New thread-based implementation also works on non-Unix
platforms (Cygwin).  Provers are no longer hardwired, but defined
within the theory via plain ML wrapper functions.  Basic Sledgehammer
commands are covered in the isar-ref manual.

* Wrapper scripts for remote SystemOnTPTP service allows to use
sledgehammer without local ATP installation (Vampire etc.). Other
provers may be included via suitable ML wrappers, see also

* ATP selection (E/Vampire/Spass) is now via Proof General's settings

* The metis method no longer fails because the theorem is too trivial
(contains the empty clause).

* The metis method now fails in the usual manner, rather than raising
an exception, if it determines that it cannot prove the theorem.

* Method "coherent" implements a prover for coherent logic (see also

* Constants "undefined" and "default" replace "arbitrary".  Usually
"undefined" is the right choice to replace "arbitrary", though
logically there is no difference.  INCOMPATIBILITY.

* Command "value" now integrates different evaluation mechanisms.  The
result of the first successful evaluation mechanism is printed.  In
square brackets a particular named evaluation mechanisms may be
specified (currently, [SML], [code] or [nbe]).  See further

* Normalization by evaluation now allows non-leftlinear equations.
Declare with attribute [code nbe].

* Methods "case_tac" and "induct_tac" now refer to the very same rules
as the structured Isar versions "cases" and "induct", cf. the
corresponding "cases" and "induct" attributes.  Mutual induction rules
are now presented as a list of individual projections
(e.g. foo_bar.inducts for types foo and bar); the old format with
explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
rare situations a different rule is selected --- notably nested tuple
elimination instead of former prod.exhaust: use explicit (case_tac t
rule: prod.exhaust) here.

* Attributes "cases", "induct", "coinduct" support "del" option.

* Removed fact "case_split_thm", which duplicates "case_split".

* The option datatype has been moved to a new theory Option.  Renamed
option_map to, and o2s to Option.set, INCOMPATIBILITY.

* New predicate "strict_mono" classifies strict functions on partial
orders.  With strict functions on linear orders, reasoning about
(in)equalities is facilitated by theorems "strict_mono_eq",
"strict_mono_less_eq" and "strict_mono_less".

* Some set operations are now proper qualified constants with
authentic syntax.  INCOMPATIBILITY:

    op Int ~>   Set.Int
    op Un ~>    Set.Un
    INTER ~>    Set.INTER
    UNION ~>    Set.UNION
    Inter ~>    Set.Inter
    Union ~>    Set.Union
    {} ~>       Set.empty
    UNIV ~>     Set.UNIV

* Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
theory Set.

* Auxiliary class "itself" has disappeared -- classes without any
parameter are treated as expected by the 'class' command.

* Leibnitz's Series for Pi and the arcus tangens and logarithm series.

* Common decision procedures (Cooper, MIR, Ferrack, Approximation,
Dense_Linear_Order) are now in directory HOL/Decision_Procs.

* Theory src/HOL/Decision_Procs/Approximation provides the new proof
method "approximation".  It proves formulas on real values by using
interval arithmetic.  In the formulas are also the transcendental
functions sin, cos, tan, atan, ln, exp and the constant pi are
allowed. For examples see

* Theory "Reflection" now resides in HOL/Library.

* Entry point to Word library now simply named "Word".

* Made source layout more coherent with logical distribution

    src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
    src/HOL/Library/Code_Message.thy ~> src/HOL/
    src/HOL/Library/GCD.thy ~> src/HOL/
    src/HOL/Library/Order_Relation.thy ~> src/HOL/
    src/HOL/Library/Parity.thy ~> src/HOL/
    src/HOL/Library/Univ_Poly.thy ~> src/HOL/
    src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
    src/HOL/Real/Lubs.thy ~> src/HOL/
    src/HOL/Real/PReal.thy ~> src/HOL/
    src/HOL/Real/Rational.thy ~> src/HOL/
    src/HOL/Real/RComplete.thy ~> src/HOL/
    src/HOL/Real/RealDef.thy ~> src/HOL/
    src/HOL/Real/RealPow.thy ~> src/HOL/
    src/HOL/Real/Real.thy ~> src/HOL/
    src/HOL/Complex/Complex_Main.thy ~> src/HOL/
    src/HOL/Complex/Complex.thy ~> src/HOL/
    src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
    src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
    src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
    src/HOL/Hyperreal/Fact.thy ~> src/HOL/
    src/HOL/Hyperreal/Integration.thy ~> src/HOL/
    src/HOL/Hyperreal/Lim.thy ~> src/HOL/
    src/HOL/Hyperreal/Ln.thy ~> src/HOL/
    src/HOL/Hyperreal/Log.thy ~> src/HOL/
    src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
    src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
    src/HOL/Hyperreal/Series.thy ~> src/HOL/
    src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
    src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
    src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
    src/HOL/Real/Float ~> src/HOL/Library/
    src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
    src/HOL/Real/RealVector.thy ~> src/HOL/

    src/HOL/arith_data.ML ~> src/HOL/Tools
    src/HOL/hologic.ML ~> src/HOL/Tools
    src/HOL/simpdata.ML ~> src/HOL/Tools
    src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
    src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
    src/HOL/nat_simprocs.ML ~> src/HOL/Tools
    src/HOL/Real/float_arith.ML ~> src/HOL/Tools
    src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
    src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
    src/HOL/Real/real_arith.ML ~> src/HOL/Tools

    src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
    src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
    src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
    src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
    src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
    src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL

* If methods "eval" and "evaluation" encounter a structured proof
state with !!/==>, only the conclusion is evaluated to True (if
possible), avoiding strange error messages.

* Method "sizechange" automates termination proofs using (a
modification of) the size-change principle.  Requires SAT solver.  See
src/HOL/ex/Termination.thy for examples.

* Simplifier: simproc for let expressions now unfolds if bound
variable occurs at most once in let expression body.  INCOMPATIBILITY.

* Method "arith": Linear arithmetic now ignores all inequalities when
fast_arith_neq_limit is exceeded, instead of giving up entirely.