NEWS
author blanchet
Tue Jun 07 08:52:35 2011 +0200 (2011-06-07)
changeset 43228 2ed2f092e990
parent 43206 831d28439b3a
child 43319 048c7eea1a71
permissions -rw-r--r--
obsoleted "metisFT", and added "no_types" version of Metis as fallback to Sledgehammer after noticing how useful it can be
     1 Isabelle NEWS -- history user-relevant changes
     2 ==============================================
     3 
     4 New in this Isabelle version
     5 ----------------------------
     6 
     7 *** General ***
     8 
     9 * Theory loader: source files are identified by content via SHA1
    10 digests.  Discontinued former path/modtime identification and optional
    11 ISABELLE_FILE_IDENT plugin scripts.
    12 
    13 * Parallelization of nested Isar proofs is subject to
    14 Goal.parallel_proofs_threshold (default 100).  See also isabelle
    15 usedir option -Q.
    16 
    17 * Discontinued support for Poly/ML 5.2, which was the last version
    18 without proper multithreading and TimeLimit implementation.
    19 
    20 * Discontinued old lib/scripts/polyml-platform, which has been
    21 obsolete since Isabelle2009-2.
    22 
    23 * Theory loader: source files are exclusively located via the master
    24 directory of each theory node (where the .thy file itself resides).
    25 The global load path (such as src/HOL/Library) is has been
    26 discontinued.  INCOMPATIBILITY.
    27 
    28 * Various optional external tools are referenced more robustly and
    29 uniformly by explicit Isabelle settings as follows:
    30 
    31   ISABELLE_CSDP   (formerly CSDP_EXE)
    32   ISABELLE_GHC    (formerly EXEC_GHC or GHC_PATH)
    33   ISABELLE_OCAML  (formerly EXEC_OCAML)
    34   ISABELLE_SWIPL  (formerly EXEC_SWIPL)
    35   ISABELLE_YAP    (formerly EXEC_YAP)
    36 
    37 Note that automated detection from the file-system or search path has
    38 been discontinued.  INCOMPATIBILITY.
    39 
    40 * Name space: former unsynchronized references are now proper
    41 configuration options, with more conventional names:
    42 
    43   long_names   ~> names_long
    44   short_names  ~> names_short
    45   unique_names ~> names_unique
    46 
    47 Minor INCOMPATIBILITY, need to declare options in context like this:
    48 
    49   declare [[names_unique = false]]
    50 
    51 * Literal facts `prop` may contain dummy patterns, e.g. `_ = _`.  Note
    52 that the result needs to be unique, which means fact specifications
    53 may have to be refined after enriching a proof context.
    54 
    55 * Isabelle/Isar reference manual provides more formal references in
    56 syntax diagrams.
    57 
    58 
    59 *** HOL ***
    60 
    61 * Finite_Set.thy: more coherent development of fold_set locales:
    62 
    63     locale fun_left_comm ~> locale comp_fun_commute
    64     locale fun_left_comm_idem ~> locale comp_fun_idem
    65     
    66 Both use point-free characterisation; interpretation proofs may need adjustment.
    67 INCOMPATIBILITY.
    68 
    69 * Code generation:
    70   - theory Library/Code_Char_ord provides native ordering of characters
    71     in the target language.
    72     
    73 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
    74 
    75 * Nitpick:
    76   - Added "need" and "total_consts" options.
    77   - Reintroduced "show_skolems" option by popular demand.
    78   - Renamed attribute: nitpick_def ~> nitpick_unfold.
    79     INCOMPATIBILITY.
    80 
    81 * Sledgehammer:
    82   - sledgehammer available_provers ~> sledgehammer supported_provers
    83     INCOMPATIBILITY.
    84   - Added support for SNARK and ToFoF-E on SystemOnTPTP and for simply typed
    85     TPTP problems (TFF).
    86   - Added "type_sys", "max_mono_iters", and "max_new_mono_instances" options.
    87 
    88 * Metis:
    89   - Removed "metisF" -- use "metis" instead.
    90   - Obsoleted "metisFT" -- use "metis (full_types)" instead.
    91 
    92 * "try":
    93   - Added "simp:", "intro:", and "elim:" options.
    94 
    95 * Quickcheck:
    96   - Added "eval" option to evaluate terms for the found counterexample
    97     (currently only supported by the default (exhaustive) tester)
    98   - Added post-processing of terms to obtain readable counterexamples
    99     (currently only supported by the default (exhaustive) tester)
   100 
   101 * Function package: discontinued option "tailrec".
   102 INCOMPATIBILITY. Use partial_function instead.
   103 
   104 * HOL-Probability:
   105   - Caratheodory's extension lemma is now proved for ring_of_sets.
   106   - Infinite products of probability measures are now available.
   107   - Use extended reals instead of positive extended reals.
   108     INCOMPATIBILITY.
   109 
   110 
   111 *** Document preparation ***
   112 
   113 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
   114 isar-ref manual.
   115 
   116 * Localized \isabellestyle switch can be used within blocks or groups
   117 like this:
   118 
   119   \isabellestyle{it}  %preferred default
   120   {\isabellestylett @{text "typewriter stuff"}}
   121 
   122 * New term style "isub" as ad-hoc conversion of variables x1, y23 into
   123 subscripted form x\<^isub>1, y\<^isub>2\<^isub>3.
   124 
   125 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
   126 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
   127 
   128 
   129 *** ML ***
   130 
   131 * Isabelle_Process.is_active allows tools to check if the official
   132 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
   133 (better known as Proof General).
   134 
   135 * Structure Proof_Context follows standard naming scheme.  Old
   136 ProofContext is still available for some time as legacy alias.
   137 
   138 * Structure Timing provides various operations for timing; supersedes
   139 former start_timing/end_timing etc.
   140 
   141 * Path.print is the official way to show file-system paths to users
   142 (including quotes etc.).
   143 
   144 * Inner syntax: identifiers in parse trees of generic categories
   145 "logic", "aprop", "idt" etc. carry position information (disguised as
   146 type constraints).  Occasional INCOMPATIBILITY with non-compliant
   147 translations that choke on unexpected type constraints.  Positions can
   148 be stripped in ML translations via Syntax.strip_positions /
   149 Syntax.strip_positions_ast, or via the syntax constant
   150 "_strip_positions" within parse trees.  As last resort, positions can
   151 be disabled via the configuration option Syntax.positions, which is
   152 called "syntax_positions" in Isar attribute syntax.
   153 
   154 * Discontinued special status of various ML structures that contribute
   155 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
   156 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
   157 refer directly to Ast.Constant, Lexicon.is_identifier,
   158 Syntax_Trans.mk_binder_tr etc.
   159 
   160 * Typed print translation: discontinued show_sorts argument, which is
   161 already available via context of "advanced" translation.
   162 
   163 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
   164 goal states; body tactic needs to address all subgoals uniformly.
   165 
   166 * Slightly more special eq_list/eq_set, with shortcut involving
   167 pointer equality (assumes that eq relation is reflexive).
   168 
   169 * Classical tactics use proper Proof.context instead of historic types
   170 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
   171 operate directly on Proof.context.  Raw type claset retains its use as
   172 snapshot of the classical context, which can be recovered via
   173 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
   174 INCOMPATIBILITY, classical tactics and derived proof methods require
   175 proper Proof.context.
   176 
   177 
   178 
   179 New in Isabelle2011 (January 2011)
   180 ----------------------------------
   181 
   182 *** General ***
   183 
   184 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
   185 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
   186 useful tooltips and hyperlinks produced from its static analysis.  The
   187 bundled component provides an executable Isabelle tool that can be run
   188 like this:
   189 
   190   Isabelle2011/bin/isabelle jedit
   191 
   192 * Significantly improved Isabelle/Isar implementation manual.
   193 
   194 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
   195 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
   196 while the default heap location within that directory lacks that extra
   197 suffix.  This isolates multiple Isabelle installations from each
   198 other, avoiding problems with old settings in new versions.
   199 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
   200 
   201 * Source files are always encoded as UTF-8, instead of old-fashioned
   202 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   203 the following package declarations:
   204 
   205   \usepackage[utf8]{inputenc}
   206   \usepackage{textcomp}
   207 
   208 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   209 a Unicode character is treated as a single symbol, not a sequence of
   210 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   211 contain symbols without further backslash escapes, Unicode can now be
   212 used here as well.  Recall that Symbol.explode in ML provides a
   213 consistent view on symbols, while raw explode (or String.explode)
   214 merely give a byte-oriented representation.
   215 
   216 * Theory loader: source files are primarily located via the master
   217 directory of each theory node (where the .thy file itself resides).
   218 The global load path is still partially available as legacy feature.
   219 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   220 explicit paths, relatively to the theory.
   221 
   222 * Special treatment of ML file names has been discontinued.
   223 Historically, optional extensions .ML or .sml were added on demand --
   224 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   225 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   226 
   227 * Various options that affect pretty printing etc. are now properly
   228 handled within the context via configuration options, instead of
   229 unsynchronized references or print modes.  There are both ML Config.T
   230 entities and Isar declaration attributes to access these.
   231 
   232   ML (Config.T)                 Isar (attribute)
   233 
   234   eta_contract                  eta_contract
   235   show_brackets                 show_brackets
   236   show_sorts                    show_sorts
   237   show_types                    show_types
   238   show_question_marks           show_question_marks
   239   show_consts                   show_consts
   240   show_abbrevs                  show_abbrevs
   241 
   242   Syntax.ast_trace              syntax_ast_trace
   243   Syntax.ast_stat               syntax_ast_stat
   244   Syntax.ambiguity_level        syntax_ambiguity_level
   245 
   246   Goal_Display.goals_limit      goals_limit
   247   Goal_Display.show_main_goal   show_main_goal
   248 
   249   Method.rule_trace             rule_trace
   250 
   251   Thy_Output.display            thy_output_display
   252   Thy_Output.quotes             thy_output_quotes
   253   Thy_Output.indent             thy_output_indent
   254   Thy_Output.source             thy_output_source
   255   Thy_Output.break              thy_output_break
   256 
   257 Note that corresponding "..._default" references in ML may only be
   258 changed globally at the ROOT session setup, but *not* within a theory.
   259 The option "show_abbrevs" supersedes the former print mode
   260 "no_abbrevs" with inverted meaning.
   261 
   262 * More systematic naming of some configuration options.
   263 INCOMPATIBILITY.
   264 
   265   trace_simp  ~>  simp_trace
   266   debug_simp  ~>  simp_debug
   267 
   268 * Support for real valued configuration options, using simplistic
   269 floating-point notation that coincides with the inner syntax for
   270 float_token.
   271 
   272 * Support for real valued preferences (with approximative PGIP type):
   273 front-ends need to accept "pgint" values in float notation.
   274 INCOMPATIBILITY.
   275 
   276 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   277 DejaVu Sans.
   278 
   279 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   280 
   281 
   282 *** Pure ***
   283 
   284 * Command 'type_synonym' (with single argument) replaces somewhat
   285 outdated 'types', which is still available as legacy feature for some
   286 time.
   287 
   288 * Command 'nonterminal' (with 'and' separated list of arguments)
   289 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   290 
   291 * Command 'notepad' replaces former 'example_proof' for
   292 experimentation in Isar without any result.  INCOMPATIBILITY.
   293 
   294 * Locale interpretation commands 'interpret' and 'sublocale' accept
   295 lists of equations to map definitions in a locale to appropriate
   296 entities in the context of the interpretation.  The 'interpretation'
   297 command already provided this functionality.
   298 
   299 * Diagnostic command 'print_dependencies' prints the locale instances
   300 that would be activated if the specified expression was interpreted in
   301 the current context.  Variant "print_dependencies!" assumes a context
   302 without interpretations.
   303 
   304 * Diagnostic command 'print_interps' prints interpretations in proofs
   305 in addition to interpretations in theories.
   306 
   307 * Discontinued obsolete 'global' and 'local' commands to manipulate
   308 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   309 Sign.root_path and Sign.local_path may be applied directly where this
   310 feature is still required for historical reasons.
   311 
   312 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   313 'definition' instead.
   314 
   315 * The "prems" fact, which refers to the accidental collection of
   316 foundational premises in the context, is now explicitly marked as
   317 legacy feature and will be discontinued soon.  Consider using "assms"
   318 of the head statement or reference facts by explicit names.
   319 
   320 * Document antiquotations @{class} and @{type} print classes and type
   321 constructors.
   322 
   323 * Document antiquotation @{file} checks file/directory entries within
   324 the local file system.
   325 
   326 
   327 *** HOL ***
   328 
   329 * Coercive subtyping: functions can be declared as coercions and type
   330 inference will add them as necessary upon input of a term.  Theory
   331 Complex_Main declares real :: nat => real and real :: int => real as
   332 coercions. A coercion function f is declared like this:
   333 
   334   declare [[coercion f]]
   335 
   336 To lift coercions through type constructors (e.g. from nat => real to
   337 nat list => real list), map functions can be declared, e.g.
   338 
   339   declare [[coercion_map map]]
   340 
   341 Currently coercion inference is activated only in theories including
   342 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   343 the configuration option "coercion_enabled", e.g. it can be enabled in
   344 other theories like this:
   345 
   346   declare [[coercion_enabled]]
   347 
   348 * Command 'partial_function' provides basic support for recursive
   349 function definitions over complete partial orders.  Concrete instances
   350 are provided for i) the option type, ii) tail recursion on arbitrary
   351 types, and iii) the heap monad of Imperative_HOL.  See
   352 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   353 for examples.
   354 
   355 * Function package: f.psimps rules are no longer implicitly declared
   356 as [simp].  INCOMPATIBILITY.
   357 
   358 * Datatype package: theorems generated for executable equality (class
   359 "eq") carry proper names and are treated as default code equations.
   360 
   361 * Inductive package: now offers command 'inductive_simps' to
   362 automatically derive instantiated and simplified equations for
   363 inductive predicates, similar to 'inductive_cases'.
   364 
   365 * Command 'enriched_type' allows to register properties of the
   366 functorial structure of types.
   367 
   368 * Improved infrastructure for term evaluation using code generator
   369 techniques, in particular static evaluation conversions.
   370 
   371 * Code generator: Scala (2.8 or higher) has been added to the target
   372 languages.
   373 
   374 * Code generator: globbing constant expressions "*" and "Theory.*"
   375 have been replaced by the more idiomatic "_" and "Theory._".
   376 INCOMPATIBILITY.
   377 
   378 * Code generator: export_code without explicit file declaration prints
   379 to standard output.  INCOMPATIBILITY.
   380 
   381 * Code generator: do not print function definitions for case
   382 combinators any longer.
   383 
   384 * Code generator: simplification with rules determined with
   385 src/Tools/Code/code_simp.ML and method "code_simp".
   386 
   387 * Code generator for records: more idiomatic representation of record
   388 types.  Warning: records are not covered by ancient SML code
   389 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   390 rep_datatype declaration helps to succeed then:
   391 
   392   record 'a foo = ...
   393   ...
   394   rep_datatype foo_ext ...
   395 
   396 * Records: logical foundation type for records does not carry a
   397 '_type' suffix any longer (obsolete due to authentic syntax).
   398 INCOMPATIBILITY.
   399 
   400 * Quickcheck now by default uses exhaustive testing instead of random
   401 testing.  Random testing can be invoked by "quickcheck [random]",
   402 exhaustive testing by "quickcheck [exhaustive]".
   403 
   404 * Quickcheck instantiates polymorphic types with small finite
   405 datatypes by default. This enables a simple execution mechanism to
   406 handle quantifiers and function equality over the finite datatypes.
   407 
   408 * Quickcheck random generator has been renamed from "code" to
   409 "random".  INCOMPATIBILITY.
   410 
   411 * Quickcheck now has a configurable time limit which is set to 30
   412 seconds by default. This can be changed by adding [timeout = n] to the
   413 quickcheck command. The time limit for Auto Quickcheck is still set
   414 independently.
   415 
   416 * Quickcheck in locales considers interpretations of that locale for
   417 counter example search.
   418 
   419 * Sledgehammer:
   420   - Added "smt" and "remote_smt" provers based on the "smt" proof
   421     method. See the Sledgehammer manual for details ("isabelle doc
   422     sledgehammer").
   423   - Renamed commands:
   424     sledgehammer atp_info ~> sledgehammer running_provers
   425     sledgehammer atp_kill ~> sledgehammer kill_provers
   426     sledgehammer available_atps ~> sledgehammer available_provers
   427     INCOMPATIBILITY.
   428   - Renamed options:
   429     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   430     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   431     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   432     (and "ms" and "min" are no longer supported)
   433     INCOMPATIBILITY.
   434 
   435 * Nitpick:
   436   - Renamed options:
   437     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   438     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   439     INCOMPATIBILITY.
   440   - Added support for partial quotient types.
   441   - Added local versions of the "Nitpick.register_xxx" functions.
   442   - Added "whack" option.
   443   - Allow registration of quotient types as codatatypes.
   444   - Improved "merge_type_vars" option to merge more types.
   445   - Removed unsound "fast_descrs" option.
   446   - Added custom symmetry breaking for datatypes, making it possible to reach
   447     higher cardinalities.
   448   - Prevent the expansion of too large definitions.
   449 
   450 * Proof methods "metis" and "meson" now have configuration options
   451 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   452 to diagnose these tools. E.g.
   453 
   454     using [[metis_trace = true]]
   455 
   456 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   457 manually as command 'solve_direct'.
   458 
   459 * The default SMT solver Z3 must be enabled explicitly (due to
   460 licensing issues) by setting the environment variable
   461 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   462 commercial applications, the SMT solver CVC3 is provided as fall-back;
   463 changing the SMT solver is done via the configuration option
   464 "smt_solver".
   465 
   466 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   467 i.e. "remote_cvc3" and "remote_z3".
   468 
   469 * Added basic SMT support for datatypes, records, and typedefs using
   470 the oracle mode (no proofs).  Direct support of pairs has been dropped
   471 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   472 support for a similar behavior).  Minor INCOMPATIBILITY.
   473 
   474 * Changed SMT configuration options:
   475   - Renamed:
   476     z3_proofs ~> smt_oracle (with inverted meaning)
   477     z3_trace_assms ~> smt_trace_used_facts
   478     INCOMPATIBILITY.
   479   - Added:
   480     smt_verbose
   481     smt_random_seed
   482     smt_datatypes
   483     smt_infer_triggers
   484     smt_monomorph_limit
   485     cvc3_options
   486     remote_cvc3_options
   487     remote_z3_options
   488     yices_options
   489 
   490 * Boogie output files (.b2i files) need to be declared in the theory
   491 header.
   492 
   493 * Simplification procedure "list_to_set_comprehension" rewrites list
   494 comprehensions applied to List.set to set comprehensions.  Occasional
   495 INCOMPATIBILITY, may be deactivated like this:
   496 
   497   declare [[simproc del: list_to_set_comprehension]]
   498 
   499 * Removed old version of primrec package.  INCOMPATIBILITY.
   500 
   501 * Removed simplifier congruence rule of "prod_case", as has for long
   502 been the case with "split".  INCOMPATIBILITY.
   503 
   504 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   505 
   506 * Removed [split_format ... and ... and ...] version of
   507 [split_format].  Potential INCOMPATIBILITY.
   508 
   509 * Predicate "sorted" now defined inductively, with nice induction
   510 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   511 
   512 * Constant "contents" renamed to "the_elem", to free the generic name
   513 contents for other uses.  INCOMPATIBILITY.
   514 
   515 * Renamed class eq and constant eq (for code generation) to class
   516 equal and constant equal, plus renaming of related facts and various
   517 tuning.  INCOMPATIBILITY.
   518 
   519 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   520 
   521 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   522 INCOMPATIBILITY.
   523 
   524 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   525 avoid confusion with finite sets.  INCOMPATIBILITY.
   526 
   527 * Abandoned locales equiv, congruent and congruent2 for equivalence
   528 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   529 for congruent(2)).
   530 
   531 * Some previously unqualified names have been qualified:
   532 
   533   types
   534     bool ~> HOL.bool
   535     nat ~> Nat.nat
   536 
   537   constants
   538     Trueprop ~> HOL.Trueprop
   539     True ~> HOL.True
   540     False ~> HOL.False
   541     op & ~> HOL.conj
   542     op | ~> HOL.disj
   543     op --> ~> HOL.implies
   544     op = ~> HOL.eq
   545     Not ~> HOL.Not
   546     The ~> HOL.The
   547     All ~> HOL.All
   548     Ex ~> HOL.Ex
   549     Ex1 ~> HOL.Ex1
   550     Let ~> HOL.Let
   551     If ~> HOL.If
   552     Ball ~> Set.Ball
   553     Bex ~> Set.Bex
   554     Suc ~> Nat.Suc
   555     Pair ~> Product_Type.Pair
   556     fst ~> Product_Type.fst
   557     snd ~> Product_Type.snd
   558     curry ~> Product_Type.curry
   559     op : ~> Set.member
   560     Collect ~> Set.Collect
   561 
   562 INCOMPATIBILITY.
   563 
   564 * More canonical naming convention for some fundamental definitions:
   565 
   566     bot_bool_eq ~> bot_bool_def
   567     top_bool_eq ~> top_bool_def
   568     inf_bool_eq ~> inf_bool_def
   569     sup_bool_eq ~> sup_bool_def
   570     bot_fun_eq  ~> bot_fun_def
   571     top_fun_eq  ~> top_fun_def
   572     inf_fun_eq  ~> inf_fun_def
   573     sup_fun_eq  ~> sup_fun_def
   574 
   575 INCOMPATIBILITY.
   576 
   577 * More stylized fact names:
   578 
   579   expand_fun_eq ~> fun_eq_iff
   580   expand_set_eq ~> set_eq_iff
   581   set_ext       ~> set_eqI
   582   nat_number    ~> eval_nat_numeral
   583 
   584 INCOMPATIBILITY.
   585 
   586 * Refactoring of code-generation specific operations in theory List:
   587 
   588   constants
   589     null ~> List.null
   590 
   591   facts
   592     mem_iff ~> member_def
   593     null_empty ~> null_def
   594 
   595 INCOMPATIBILITY.  Note that these were not supposed to be used
   596 regularly unless for striking reasons; their main purpose was code
   597 generation.
   598 
   599 Various operations from the Haskell prelude are used for generating
   600 Haskell code.
   601 
   602 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   603 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   604 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   605 
   606 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   607 "*" and "+" respectively.  INCOMPATIBILITY.
   608 
   609 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   610 "Sum_Type.Plus" instead.
   611 
   612 * Constant "split" has been merged with constant "prod_case"; names of
   613 ML functions, facts etc. involving split have been retained so far,
   614 though.  INCOMPATIBILITY.
   615 
   616 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   617 instead.  INCOMPATIBILITY.
   618 
   619 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   620 INCOMPATIBILITY.
   621 
   622 * Former theory Library/Enum is now part of the HOL-Main image.
   623 INCOMPATIBILITY: all constants of the Enum theory now have to be
   624 referred to by its qualified name.
   625 
   626   enum    ~>  Enum.enum
   627   nlists  ~>  Enum.nlists
   628   product ~>  Enum.product
   629 
   630 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   631 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   632 INCOMPATIBILITY.
   633 
   634 * Theory Library/SetsAndFunctions has been split into
   635 Library/Function_Algebras and Library/Set_Algebras; canonical names
   636 for instance definitions for functions; various improvements.
   637 INCOMPATIBILITY.
   638 
   639 * Theory Library/Multiset provides stable quicksort implementation of
   640 sort_key.
   641 
   642 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   643 INCOMPATIBILITY.
   644 
   645 * Session Multivariate_Analysis: introduced a type class for euclidean
   646 space.  Most theorems are now stated in terms of euclidean spaces
   647 instead of finite cartesian products.
   648 
   649   types
   650     real ^ 'n ~>  'a::real_vector
   651               ~>  'a::euclidean_space
   652               ~>  'a::ordered_euclidean_space
   653         (depends on your needs)
   654 
   655   constants
   656      _ $ _        ~> _ $$ _
   657      \<chi> x. _  ~> \<chi>\<chi> x. _
   658      CARD('n)     ~> DIM('a)
   659 
   660 Also note that the indices are now natural numbers and not from some
   661 finite type. Finite cartesian products of euclidean spaces, products
   662 of euclidean spaces the real and complex numbers are instantiated to
   663 be euclidean_spaces.  INCOMPATIBILITY.
   664 
   665 * Session Probability: introduced pextreal as positive extended real
   666 numbers.  Use pextreal as value for measures.  Introduce the
   667 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   668 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   669 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   670 
   671 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   672 INCOMPATIBILITY.
   673 
   674 * Session SPARK (with image HOL-SPARK) provides commands to load and
   675 prove verification conditions generated by the SPARK Ada program
   676 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   677 
   678 
   679 *** HOL-Algebra ***
   680 
   681 * Theorems for additive ring operations (locale abelian_monoid and
   682 descendants) are generated by interpretation from their multiplicative
   683 counterparts.  Names (in particular theorem names) have the mandatory
   684 qualifier 'add'.  Previous theorem names are redeclared for
   685 compatibility.
   686 
   687 * Structure "int_ring" is now an abbreviation (previously a
   688 definition).  This fits more natural with advanced interpretations.
   689 
   690 
   691 *** HOLCF ***
   692 
   693 * The domain package now runs in definitional mode by default: The
   694 former command 'new_domain' is now called 'domain'.  To use the domain
   695 package in its original axiomatic mode, use 'domain (unsafe)'.
   696 INCOMPATIBILITY.
   697 
   698 * The new class "domain" is now the default sort.  Class "predomain"
   699 is an unpointed version of "domain". Theories can be updated by
   700 replacing sort annotations as shown below.  INCOMPATIBILITY.
   701 
   702   'a::type ~> 'a::countable
   703   'a::cpo  ~> 'a::predomain
   704   'a::pcpo ~> 'a::domain
   705 
   706 * The old type class "rep" has been superseded by class "domain".
   707 Accordingly, users of the definitional package must remove any
   708 "default_sort rep" declarations.  INCOMPATIBILITY.
   709 
   710 * The domain package (definitional mode) now supports unpointed
   711 predomain argument types, as long as they are marked 'lazy'. (Strict
   712 arguments must be in class "domain".) For example, the following
   713 domain definition now works:
   714 
   715   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   716 
   717 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   718 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   719 'a option, and 'a list.  Additionally, it configures fixrec and the
   720 domain package to work with these types.  For example:
   721 
   722   fixrec isInl :: "('a + 'b) u -> tr"
   723     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   724 
   725   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   726 
   727 * The "(permissive)" option of fixrec has been replaced with a
   728 per-equation "(unchecked)" option. See
   729 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
   730 
   731 * The "bifinite" class no longer fixes a constant "approx"; the class
   732 now just asserts that such a function exists.  INCOMPATIBILITY.
   733 
   734 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
   735 defines an embedding of type 'a defl into udom by default; instances
   736 of "bifinite" and "domain" classes are available in
   737 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
   738 
   739 * The syntax "REP('a)" has been replaced with "DEFL('a)".
   740 
   741 * The predicate "directed" has been removed.  INCOMPATIBILITY.
   742 
   743 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
   744 
   745 * The function "cprod_map" has been renamed to "prod_map".
   746 INCOMPATIBILITY.
   747 
   748 * The monadic bind operator on each powerdomain has new binder syntax
   749 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
   750 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
   751 
   752 * The infix syntax for binary union on each powerdomain has changed
   753 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
   754 syntax.  INCOMPATIBILITY.
   755 
   756 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
   757 still supported as an input translation.
   758 
   759 * Renamed some theorems (the original names are also still available).
   760 
   761   expand_fun_below   ~> fun_below_iff
   762   below_fun_ext      ~> fun_belowI
   763   expand_cfun_eq     ~> cfun_eq_iff
   764   ext_cfun           ~> cfun_eqI
   765   expand_cfun_below  ~> cfun_below_iff
   766   below_cfun_ext     ~> cfun_belowI
   767   cont2cont_Rep_CFun ~> cont2cont_APP
   768 
   769 * The Abs and Rep functions for various types have changed names.
   770 Related theorem names have also changed to match. INCOMPATIBILITY.
   771 
   772   Rep_CFun  ~> Rep_cfun
   773   Abs_CFun  ~> Abs_cfun
   774   Rep_Sprod ~> Rep_sprod
   775   Abs_Sprod ~> Abs_sprod
   776   Rep_Ssum  ~> Rep_ssum
   777   Abs_Ssum  ~> Abs_ssum
   778 
   779 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   780 been renamed to *_bottom_iff.  INCOMPATIBILITY.
   781 
   782 * Various changes to bisimulation/coinduction with domain package:
   783 
   784   - Definitions of "bisim" constants no longer mention definedness.
   785   - With mutual recursion, "bisim" predicate is now curried.
   786   - With mutual recursion, each type gets a separate coind theorem.
   787   - Variable names in bisim_def and coinduct rules have changed.
   788 
   789 INCOMPATIBILITY.
   790 
   791 * Case combinators generated by the domain package for type "foo" are
   792 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
   793 
   794 * Several theorems have been renamed to more accurately reflect the
   795 names of constants and types involved.  INCOMPATIBILITY.
   796 
   797   thelub_const    ~> lub_const
   798   lub_const       ~> is_lub_const
   799   thelubI         ~> lub_eqI
   800   is_lub_lub      ~> is_lubD2
   801   lubI            ~> is_lub_lub
   802   unique_lub      ~> is_lub_unique
   803   is_ub_lub       ~> is_lub_rangeD1
   804   lub_bin_chain   ~> is_lub_bin_chain
   805   lub_fun         ~> is_lub_fun
   806   thelub_fun      ~> lub_fun
   807   thelub_cfun     ~> lub_cfun
   808   thelub_Pair     ~> lub_Pair
   809   lub_cprod       ~> is_lub_prod
   810   thelub_cprod    ~> lub_prod
   811   minimal_cprod   ~> minimal_prod
   812   inst_cprod_pcpo ~> inst_prod_pcpo
   813   UU_I            ~> bottomI
   814   compact_UU      ~> compact_bottom
   815   deflation_UU    ~> deflation_bottom
   816   finite_deflation_UU ~> finite_deflation_bottom
   817 
   818 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
   819 
   820   sq_ord_less_eq_trans ~> below_eq_trans
   821   sq_ord_eq_less_trans ~> eq_below_trans
   822   refl_less            ~> below_refl
   823   trans_less           ~> below_trans
   824   antisym_less         ~> below_antisym
   825   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
   826   box_less             ~> box_below
   827   rev_trans_less       ~> rev_below_trans
   828   not_less2not_eq      ~> not_below2not_eq
   829   less_UU_iff          ~> below_UU_iff
   830   flat_less_iff        ~> flat_below_iff
   831   adm_less             ~> adm_below
   832   adm_not_less         ~> adm_not_below
   833   adm_compact_not_less ~> adm_compact_not_below
   834   less_fun_def         ~> below_fun_def
   835   expand_fun_less      ~> fun_below_iff
   836   less_fun_ext         ~> fun_belowI
   837   less_discr_def       ~> below_discr_def
   838   discr_less_eq        ~> discr_below_eq
   839   less_unit_def        ~> below_unit_def
   840   less_cprod_def       ~> below_prod_def
   841   prod_lessI           ~> prod_belowI
   842   Pair_less_iff        ~> Pair_below_iff
   843   fst_less_iff         ~> fst_below_iff
   844   snd_less_iff         ~> snd_below_iff
   845   expand_cfun_less     ~> cfun_below_iff
   846   less_cfun_ext        ~> cfun_belowI
   847   injection_less       ~> injection_below
   848   less_up_def          ~> below_up_def
   849   not_Iup_less         ~> not_Iup_below
   850   Iup_less             ~> Iup_below
   851   up_less              ~> up_below
   852   Def_inject_less_eq   ~> Def_below_Def
   853   Def_less_is_eq       ~> Def_below_iff
   854   spair_less_iff       ~> spair_below_iff
   855   less_sprod           ~> below_sprod
   856   spair_less           ~> spair_below
   857   sfst_less_iff        ~> sfst_below_iff
   858   ssnd_less_iff        ~> ssnd_below_iff
   859   fix_least_less       ~> fix_least_below
   860   dist_less_one        ~> dist_below_one
   861   less_ONE             ~> below_ONE
   862   ONE_less_iff         ~> ONE_below_iff
   863   less_sinlD           ~> below_sinlD
   864   less_sinrD           ~> below_sinrD
   865 
   866 
   867 *** FOL and ZF ***
   868 
   869 * All constant names are now qualified internally and use proper
   870 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
   871 
   872 
   873 *** ML ***
   874 
   875 * Antiquotation @{assert} inlines a function bool -> unit that raises
   876 Fail if the argument is false.  Due to inlining the source position of
   877 failed assertions is included in the error output.
   878 
   879 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
   880 text is in practice always evaluated with a stable theory checkpoint.
   881 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
   882 
   883 * Antiquotation @{theory A} refers to theory A from the ancestry of
   884 the current context, not any accidental theory loader state as before.
   885 Potential INCOMPATIBILITY, subtle change in semantics.
   886 
   887 * Syntax.pretty_priority (default 0) configures the required priority
   888 of pretty-printed output and thus affects insertion of parentheses.
   889 
   890 * Syntax.default_root (default "any") configures the inner syntax
   891 category (nonterminal symbol) for parsing of terms.
   892 
   893 * Former exception Library.UnequalLengths now coincides with
   894 ListPair.UnequalLengths.
   895 
   896 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
   897 main functionality is provided by structure Simplifier.
   898 
   899 * Renamed raw "explode" function to "raw_explode" to emphasize its
   900 meaning.  Note that internally to Isabelle, Symbol.explode is used in
   901 almost all situations.
   902 
   903 * Discontinued obsolete function sys_error and exception SYS_ERROR.
   904 See implementation manual for further details on exceptions in
   905 Isabelle/ML.
   906 
   907 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   908 meaning.
   909 
   910 * Renamed structure PureThy to Pure_Thy and moved most of its
   911 operations to structure Global_Theory, to emphasize that this is
   912 rarely-used global-only stuff.
   913 
   914 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
   915 instead (or tracing for high-volume output).
   916 
   917 * Configuration option show_question_marks only affects regular pretty
   918 printing of types and terms, not raw Term.string_of_vname.
   919 
   920 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
   921 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
   922 @{thms} for most purposes.
   923 
   924 * ML structure Unsynchronized is never opened, not even in Isar
   925 interaction mode as before.  Old Unsynchronized.set etc. have been
   926 discontinued -- use plain := instead.  This should be *rare* anyway,
   927 since modern tools always work via official context data, notably
   928 configuration options.
   929 
   930 * Parallel and asynchronous execution requires special care concerning
   931 interrupts.  Structure Exn provides some convenience functions that
   932 avoid working directly with raw Interrupt.  User code must not absorb
   933 interrupts -- intermediate handling (for cleanup etc.) needs to be
   934 followed by re-raising of the original exception.  Another common
   935 source of mistakes are "handle _" patterns, which make the meaning of
   936 the program subject to physical effects of the environment.
   937 
   938 
   939 
   940 New in Isabelle2009-2 (June 2010)
   941 ---------------------------------
   942 
   943 *** General ***
   944 
   945 * Authentic syntax for *all* logical entities (type classes, type
   946 constructors, term constants): provides simple and robust
   947 correspondence between formal entities and concrete syntax.  Within
   948 the parse tree / AST representations, "constants" are decorated by
   949 their category (class, type, const) and spelled out explicitly with
   950 their full internal name.
   951 
   952 Substantial INCOMPATIBILITY concerning low-level syntax declarations
   953 and translations (translation rules and translation functions in ML).
   954 Some hints on upgrading:
   955 
   956   - Many existing uses of 'syntax' and 'translations' can be replaced
   957     by more modern 'type_notation', 'notation' and 'abbreviation',
   958     which are independent of this issue.
   959 
   960   - 'translations' require markup within the AST; the term syntax
   961     provides the following special forms:
   962 
   963       CONST c   -- produces syntax version of constant c from context
   964       XCONST c  -- literally c, checked as constant from context
   965       c         -- literally c, if declared by 'syntax'
   966 
   967     Plain identifiers are treated as AST variables -- occasionally the
   968     system indicates accidental variables via the error "rhs contains
   969     extra variables".
   970 
   971     Type classes and type constructors are marked according to their
   972     concrete syntax.  Some old translations rules need to be written
   973     for the "type" category, using type constructor application
   974     instead of pseudo-term application of the default category
   975     "logic".
   976 
   977   - 'parse_translation' etc. in ML may use the following
   978     antiquotations:
   979 
   980       @{class_syntax c}   -- type class c within parse tree / AST
   981       @{term_syntax c}    -- type constructor c within parse tree / AST
   982       @{const_syntax c}   -- ML version of "CONST c" above
   983       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
   984 
   985   - Literal types within 'typed_print_translations', i.e. those *not*
   986     represented as pseudo-terms are represented verbatim.  Use @{class
   987     c} or @{type_name c} here instead of the above syntax
   988     antiquotations.
   989 
   990 Note that old non-authentic syntax was based on unqualified base
   991 names, so all of the above "constant" names would coincide.  Recall
   992 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
   993 diagnose syntax problems.
   994 
   995 * Type constructors admit general mixfix syntax, not just infix.
   996 
   997 * Concrete syntax may be attached to local entities without a proof
   998 body, too.  This works via regular mixfix annotations for 'fix',
   999 'def', 'obtain' etc. or via the explicit 'write' command, which is
  1000 similar to the 'notation' command in theory specifications.
  1001 
  1002 * Discontinued unnamed infix syntax (legacy feature for many years) --
  1003 need to specify constant name and syntax separately.  Internal ML
  1004 datatype constructors have been renamed from InfixName to Infix etc.
  1005 Minor INCOMPATIBILITY.
  1006 
  1007 * Schematic theorem statements need to be explicitly markup as such,
  1008 via commands 'schematic_lemma', 'schematic_theorem',
  1009 'schematic_corollary'.  Thus the relevance of the proof is made
  1010 syntactically clear, which impacts performance in a parallel or
  1011 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  1012 
  1013 * Use of cumulative prems via "!" in some proof methods has been
  1014 discontinued (old legacy feature).
  1015 
  1016 * References 'trace_simp' and 'debug_simp' have been replaced by
  1017 configuration options stored in the context. Enabling tracing (the
  1018 case of debugging is similar) in proofs works via
  1019 
  1020   using [[trace_simp = true]]
  1021 
  1022 Tracing is then active for all invocations of the simplifier in
  1023 subsequent goal refinement steps. Tracing may also still be enabled or
  1024 disabled via the ProofGeneral settings menu.
  1025 
  1026 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  1027 'hide_fact' replace the former 'hide' KIND command.  Minor
  1028 INCOMPATIBILITY.
  1029 
  1030 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  1031 more efficient than combinations with -q1 or -q2.
  1032 
  1033 
  1034 *** Pure ***
  1035 
  1036 * Proofterms record type-class reasoning explicitly, using the
  1037 "unconstrain" operation internally.  This eliminates all sort
  1038 constraints from a theorem and proof, introducing explicit
  1039 OFCLASS-premises.  On the proof term level, this operation is
  1040 automatically applied at theorem boundaries, such that closed proofs
  1041 are always free of sort constraints.  INCOMPATIBILITY for tools that
  1042 inspect proof terms.
  1043 
  1044 * Local theory specifications may depend on extra type variables that
  1045 are not present in the result type -- arguments TYPE('a) :: 'a itself
  1046 are added internally.  For example:
  1047 
  1048   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  1049 
  1050 * Predicates of locales introduced by classes carry a mandatory
  1051 "class" prefix.  INCOMPATIBILITY.
  1052 
  1053 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  1054 
  1055 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  1056 'class' instead.
  1057 
  1058 * Command 'code_reflect' allows to incorporate generated ML code into
  1059 runtime environment; replaces immature code_datatype antiquotation.
  1060 INCOMPATIBILITY.
  1061 
  1062 * Code generator: simple concept for abstract datatypes obeying
  1063 invariants.
  1064 
  1065 * Code generator: details of internal data cache have no impact on the
  1066 user space functionality any longer.
  1067 
  1068 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1069 subgoals.  This is more appropriate for interpretations with 'where'.
  1070 INCOMPATIBILITY.
  1071 
  1072 * Command 'example_proof' opens an empty proof body.  This allows to
  1073 experiment with Isar, without producing any persistent result.
  1074 
  1075 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1076 within a local theory context, with explicit checking of the
  1077 constructors involved (in contrast to the raw 'syntax' versions).
  1078 
  1079 * Commands 'types' and 'typedecl' now work within a local theory
  1080 context -- without introducing dependencies on parameters or
  1081 assumptions, which is not possible in Isabelle/Pure.
  1082 
  1083 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1084 within a local theory context.  Minor INCOMPATIBILITY.
  1085 
  1086 
  1087 *** HOL ***
  1088 
  1089 * Command 'typedef' now works within a local theory context -- without
  1090 introducing dependencies on parameters or assumptions, which is not
  1091 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1092 contain multiple interpretations of local typedefs (with different
  1093 non-emptiness proofs), even in a global theory context.
  1094 
  1095 * New package for quotient types.  Commands 'quotient_type' and
  1096 'quotient_definition' may be used for defining types and constants by
  1097 quotient constructions.  An example is the type of integers created by
  1098 quotienting pairs of natural numbers:
  1099 
  1100   fun
  1101     intrel :: "(nat * nat) => (nat * nat) => bool"
  1102   where
  1103     "intrel (x, y) (u, v) = (x + v = u + y)"
  1104 
  1105   quotient_type int = "nat * nat" / intrel
  1106     by (auto simp add: equivp_def expand_fun_eq)
  1107 
  1108   quotient_definition
  1109     "0::int" is "(0::nat, 0::nat)"
  1110 
  1111 The method "lifting" can be used to lift of theorems from the
  1112 underlying "raw" type to the quotient type.  The example
  1113 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1114 construction and provides a reasoning infrastructure for finite sets.
  1115 
  1116 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1117 clash with new theory Quotient in Main HOL.
  1118 
  1119 * Moved the SMT binding into the main HOL session, eliminating
  1120 separate HOL-SMT session.
  1121 
  1122 * List membership infix mem operation is only an input abbreviation.
  1123 INCOMPATIBILITY.
  1124 
  1125 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1126 for future developements; former Library/Word.thy is still present in
  1127 the AFP entry RSAPPS.
  1128 
  1129 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1130 longer shadowed.  INCOMPATIBILITY.
  1131 
  1132 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1133 INCOMPATIBILITY.
  1134 
  1135 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1136 INCOMPATIBILITY.
  1137 
  1138 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1139 instead.  INCOMPATIBILITY.
  1140 
  1141 * Dropped several real-specific versions of lemmas about floor and
  1142 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1143 instead.  INCOMPATIBILITY.
  1144 
  1145   floor_number_of_eq         ~> floor_number_of
  1146   le_floor_eq_number_of      ~> number_of_le_floor
  1147   le_floor_eq_zero           ~> zero_le_floor
  1148   le_floor_eq_one            ~> one_le_floor
  1149   floor_less_eq_number_of    ~> floor_less_number_of
  1150   floor_less_eq_zero         ~> floor_less_zero
  1151   floor_less_eq_one          ~> floor_less_one
  1152   less_floor_eq_number_of    ~> number_of_less_floor
  1153   less_floor_eq_zero         ~> zero_less_floor
  1154   less_floor_eq_one          ~> one_less_floor
  1155   floor_le_eq_number_of      ~> floor_le_number_of
  1156   floor_le_eq_zero           ~> floor_le_zero
  1157   floor_le_eq_one            ~> floor_le_one
  1158   floor_subtract_number_of   ~> floor_diff_number_of
  1159   floor_subtract_one         ~> floor_diff_one
  1160   ceiling_number_of_eq       ~> ceiling_number_of
  1161   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1162   ceiling_le_zero_eq         ~> ceiling_le_zero
  1163   ceiling_le_eq_one          ~> ceiling_le_one
  1164   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1165   less_ceiling_eq_zero       ~> zero_less_ceiling
  1166   less_ceiling_eq_one        ~> one_less_ceiling
  1167   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1168   ceiling_less_eq_zero       ~> ceiling_less_zero
  1169   ceiling_less_eq_one        ~> ceiling_less_one
  1170   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1171   le_ceiling_eq_zero         ~> zero_le_ceiling
  1172   le_ceiling_eq_one          ~> one_le_ceiling
  1173   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1174   ceiling_subtract_one       ~> ceiling_diff_one
  1175 
  1176 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1177 application of the various fold combinators on finite sets.
  1178 
  1179 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1180 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1181 implementation.  INCOMPATIBILTY.
  1182 
  1183 * Theory Library/Coinductive_List has been removed -- superseded by
  1184 AFP/thys/Coinductive.
  1185 
  1186 * Theory PReal, including the type "preal" and related operations, has
  1187 been removed.  INCOMPATIBILITY.
  1188 
  1189 * Real: new development using Cauchy Sequences.
  1190 
  1191 * Split off theory "Big_Operators" containing setsum, setprod,
  1192 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1193 
  1194 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1195 "Int" etc.  INCOMPATIBILITY.
  1196 
  1197 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1198 
  1199 * New set of rules "ac_simps" provides combined assoc / commute
  1200 rewrites for all interpretations of the appropriate generic locales.
  1201 
  1202 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1203 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1204 appropriate and more consistent names suitable for name prefixes
  1205 within the HOL theories.  INCOMPATIBILITY.
  1206 
  1207 * Some generic constants have been put to appropriate theories:
  1208   - less_eq, less: Orderings
  1209   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1210   - inverse, divide: Rings
  1211 INCOMPATIBILITY.
  1212 
  1213 * More consistent naming of type classes involving orderings (and
  1214 lattices):
  1215 
  1216     lower_semilattice                   ~> semilattice_inf
  1217     upper_semilattice                   ~> semilattice_sup
  1218 
  1219     dense_linear_order                  ~> dense_linorder
  1220 
  1221     pordered_ab_group_add               ~> ordered_ab_group_add
  1222     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1223     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1224     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1225     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1226     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1227     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1228     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1229     pordered_comm_ring                  ~> ordered_comm_ring
  1230     pordered_comm_semiring              ~> ordered_comm_semiring
  1231     pordered_ring                       ~> ordered_ring
  1232     pordered_ring_abs                   ~> ordered_ring_abs
  1233     pordered_semiring                   ~> ordered_semiring
  1234 
  1235     ordered_ab_group_add                ~> linordered_ab_group_add
  1236     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1237     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1238     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1239     ordered_field                       ~> linordered_field
  1240     ordered_field_no_lb                 ~> linordered_field_no_lb
  1241     ordered_field_no_ub                 ~> linordered_field_no_ub
  1242     ordered_field_dense_linear_order    ~> dense_linordered_field
  1243     ordered_idom                        ~> linordered_idom
  1244     ordered_ring                        ~> linordered_ring
  1245     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1246     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1247     ordered_ring_strict                 ~> linordered_ring_strict
  1248     ordered_semidom                     ~> linordered_semidom
  1249     ordered_semiring                    ~> linordered_semiring
  1250     ordered_semiring_1                  ~> linordered_semiring_1
  1251     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1252     ordered_semiring_strict             ~> linordered_semiring_strict
  1253 
  1254   The following slightly odd type classes have been moved to a
  1255   separate theory Library/Lattice_Algebras:
  1256 
  1257     lordered_ab_group_add               ~> lattice_ab_group_add
  1258     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1259     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1260     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1261     lordered_ring                       ~> lattice_ring
  1262 
  1263 INCOMPATIBILITY.
  1264 
  1265 * Refined field classes:
  1266   - classes division_ring_inverse_zero, field_inverse_zero,
  1267     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1268     subsumes former division_by_zero class;
  1269   - numerous lemmas have been ported from field to division_ring.
  1270 INCOMPATIBILITY.
  1271 
  1272 * Refined algebra theorem collections:
  1273   - dropped theorem group group_simps, use algebra_simps instead;
  1274   - dropped theorem group ring_simps, use field_simps instead;
  1275   - proper theorem collection field_simps subsumes former theorem
  1276     groups field_eq_simps and field_simps;
  1277   - dropped lemma eq_minus_self_iff which is a duplicate for
  1278     equal_neg_zero.
  1279 INCOMPATIBILITY.
  1280 
  1281 * Theory Finite_Set and List: some lemmas have been generalized from
  1282 sets to lattices:
  1283 
  1284   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1285   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1286   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1287   union_Union_fold_union        ~> sup_Sup_fold_sup
  1288   Inter_fold_inter              ~> Inf_fold_inf
  1289   Union_fold_union              ~> Sup_fold_sup
  1290   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1291   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1292   INTER_fold_inter              ~> INFI_fold_inf
  1293   UNION_fold_union              ~> SUPR_fold_sup
  1294 
  1295 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1296 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1297 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1298 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1299 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1300 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1301 
  1302 * Reorganized theory Multiset: swapped notation of pointwise and
  1303 multiset order:
  1304 
  1305   - pointwise ordering is instance of class order with standard syntax
  1306     <= and <;
  1307   - multiset ordering has syntax <=# and <#; partial order properties
  1308     are provided by means of interpretation with prefix
  1309     multiset_order;
  1310   - less duplication, less historical organization of sections,
  1311     conversion from associations lists to multisets, rudimentary code
  1312     generation;
  1313   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1314     if needed.
  1315 
  1316 Renamed:
  1317 
  1318   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1319   multi_count_ext  ~>  multiset_ext
  1320   diff_union_inverse2  ~>  diff_union_cancelR
  1321 
  1322 INCOMPATIBILITY.
  1323 
  1324 * Theory Permutation: replaced local "remove" by List.remove1.
  1325 
  1326 * Code generation: ML and OCaml code is decorated with signatures.
  1327 
  1328 * Theory List: added transpose.
  1329 
  1330 * Library/Nat_Bijection.thy is a collection of bijective functions
  1331 between nat and other types, which supersedes the older libraries
  1332 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1333 
  1334   Constants:
  1335   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1336   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1337   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1338   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1339   Countable.pair_encode           ~> prod_encode
  1340   NatIso.prod2nat                 ~> prod_encode
  1341   NatIso.nat2prod                 ~> prod_decode
  1342   NatIso.sum2nat                  ~> sum_encode
  1343   NatIso.nat2sum                  ~> sum_decode
  1344   NatIso.list2nat                 ~> list_encode
  1345   NatIso.nat2list                 ~> list_decode
  1346   NatIso.set2nat                  ~> set_encode
  1347   NatIso.nat2set                  ~> set_decode
  1348 
  1349   Lemmas:
  1350   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1351   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1352   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1353   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1354   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1355   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1356   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1357   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1358   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1359   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1360   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1361   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1362   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1363 
  1364 * Sledgehammer:
  1365   - Renamed ATP commands:
  1366     atp_info     ~> sledgehammer running_atps
  1367     atp_kill     ~> sledgehammer kill_atps
  1368     atp_messages ~> sledgehammer messages
  1369     atp_minimize ~> sledgehammer minimize
  1370     print_atps   ~> sledgehammer available_atps
  1371     INCOMPATIBILITY.
  1372   - Added user's manual ("isabelle doc sledgehammer").
  1373   - Added option syntax and "sledgehammer_params" to customize
  1374     Sledgehammer's behavior.  See the manual for details.
  1375   - Modified the Isar proof reconstruction code so that it produces
  1376     direct proofs rather than proofs by contradiction.  (This feature
  1377     is still experimental.)
  1378   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1379     full-typed mode.
  1380   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1381 
  1382 * Nitpick:
  1383   - Added and implemented "binary_ints" and "bits" options.
  1384   - Added "std" option and implemented support for nonstandard models.
  1385   - Added and implemented "finitize" option to improve the precision
  1386     of infinite datatypes based on a monotonicity analysis.
  1387   - Added support for quotient types.
  1388   - Added support for "specification" and "ax_specification"
  1389     constructs.
  1390   - Added support for local definitions (for "function" and
  1391     "termination" proofs).
  1392   - Added support for term postprocessors.
  1393   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1394   - Improved efficiency of "destroy_constrs" optimization.
  1395   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1396     record getters.
  1397   - Fixed soundness bug related to higher-order constructors.
  1398   - Fixed soundness bug when "full_descrs" is enabled.
  1399   - Improved precision of set constructs.
  1400   - Added "atoms" option.
  1401   - Added cache to speed up repeated Kodkod invocations on the same
  1402     problems.
  1403   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1404     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1405     "SAT4J_Light".  INCOMPATIBILITY.
  1406   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1407     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1408   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1409 
  1410 * Method "induct" now takes instantiations of the form t, where t is not
  1411   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1412   If this is not intended, t has to be enclosed in parentheses.
  1413   By default, the equalities generated by definitional instantiations
  1414   are pre-simplified, which may cause parameters of inductive cases
  1415   to disappear, or may even delete some of the inductive cases.
  1416   Use "induct (no_simp)" instead of "induct" to restore the old
  1417   behaviour. The (no_simp) option is also understood by the "cases"
  1418   and "nominal_induct" methods, which now perform pre-simplification, too.
  1419   INCOMPATIBILITY.
  1420 
  1421 
  1422 *** HOLCF ***
  1423 
  1424 * Variable names in lemmas generated by the domain package have
  1425 changed; the naming scheme is now consistent with the HOL datatype
  1426 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1427 
  1428 * The domain package no longer defines the function "foo_copy" for
  1429 recursive domain "foo".  The reach lemma is now stated directly in
  1430 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1431 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1432 
  1433 * Most definedness lemmas generated by the domain package (previously
  1434 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1435 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1436 Proofs that used definedness lemmas as intro rules may break,
  1437 potential INCOMPATIBILITY.
  1438 
  1439 * Induction and casedist rules generated by the domain package now
  1440 declare proper case_names (one called "bottom", and one named for each
  1441 constructor).  INCOMPATIBILITY.
  1442 
  1443 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1444 rules are generated for each domain, INCOMPATIBILITY.
  1445 
  1446   foo_bar.reach       ~> foo.reach  bar.reach
  1447   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1448 
  1449 * Some lemmas generated by the domain package have been renamed for
  1450 consistency with the datatype package, INCOMPATIBILITY.
  1451 
  1452   foo.ind        ~> foo.induct
  1453   foo.finite_ind ~> foo.finite_induct
  1454   foo.coind      ~> foo.coinduct
  1455   foo.casedist   ~> foo.exhaust
  1456   foo.exhaust    ~> foo.nchotomy
  1457 
  1458 * For consistency with other definition packages, the fixrec package
  1459 now generates qualified theorem names, INCOMPATIBILITY.
  1460 
  1461   foo_simps  ~> foo.simps
  1462   foo_unfold ~> foo.unfold
  1463   foo_induct ~> foo.induct
  1464 
  1465 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1466 method and internal fixrec proofs now use the default simpset instead.
  1467 INCOMPATIBILITY.
  1468 
  1469 * The "contlub" predicate has been removed.  Proof scripts should use
  1470 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1471 
  1472 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1473 
  1474 * The constants cpair, cfst, and csnd have been removed in favor of
  1475 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1476 
  1477 
  1478 *** ML ***
  1479 
  1480 * Antiquotations for basic formal entities:
  1481 
  1482     @{class NAME}         -- type class
  1483     @{class_syntax NAME}  -- syntax representation of the above
  1484 
  1485     @{type_name NAME}     -- logical type
  1486     @{type_abbrev NAME}   -- type abbreviation
  1487     @{nonterminal NAME}   -- type of concrete syntactic category
  1488     @{type_syntax NAME}   -- syntax representation of any of the above
  1489 
  1490     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1491     @{const_abbrev NAME}  -- abbreviated constant
  1492     @{const_syntax NAME}  -- syntax representation of any of the above
  1493 
  1494 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1495 syntax constant (cf. 'syntax' command).
  1496 
  1497 * Antiquotation @{make_string} inlines a function to print arbitrary
  1498 values similar to the ML toplevel.  The result is compiler dependent
  1499 and may fall back on "?" in certain situations.
  1500 
  1501 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1502 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1503 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1504 not work with the asynchronous Isar document model.
  1505 
  1506 * Configuration options now admit dynamic default values, depending on
  1507 the context or even global references.
  1508 
  1509 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1510 uses an efficient external library if available (for Poly/ML).
  1511 
  1512 * Renamed some important ML structures, while keeping the old names
  1513 for some time as aliases within the structure Legacy:
  1514 
  1515   OuterKeyword  ~>  Keyword
  1516   OuterLex      ~>  Token
  1517   OuterParse    ~>  Parse
  1518   OuterSyntax   ~>  Outer_Syntax
  1519   PrintMode     ~>  Print_Mode
  1520   SpecParse     ~>  Parse_Spec
  1521   ThyInfo       ~>  Thy_Info
  1522   ThyLoad       ~>  Thy_Load
  1523   ThyOutput     ~>  Thy_Output
  1524   TypeInfer     ~>  Type_Infer
  1525 
  1526 Note that "open Legacy" simplifies porting of sources, but forgetting
  1527 to remove it again will complicate porting again in the future.
  1528 
  1529 * Most operations that refer to a global context are named
  1530 accordingly, e.g. Simplifier.global_context or
  1531 ProofContext.init_global.  There are some situations where a global
  1532 context actually works, but under normal circumstances one needs to
  1533 pass the proper local context through the code!
  1534 
  1535 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1536 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1537 Pretty.pp argument to merge, which is absent in the standard
  1538 Theory_Data version.
  1539 
  1540 * Sorts.certify_sort and derived "cert" operations for types and terms
  1541 no longer minimize sorts.  Thus certification at the boundary of the
  1542 inference kernel becomes invariant under addition of class relations,
  1543 which is an important monotonicity principle.  Sorts are now minimized
  1544 in the syntax layer only, at the boundary between the end-user and the
  1545 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1546 explicitly in rare situations.
  1547 
  1548 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1549 emphasize that this is in no way a standard operation.
  1550 INCOMPATIBILITY.
  1551 
  1552 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1553 usual for resolution.  Rare INCOMPATIBILITY.
  1554 
  1555 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1556 to emphasize that these only work in a global situation (which is
  1557 quite rare).
  1558 
  1559 * Curried take and drop in library.ML; negative length is interpreted
  1560 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1561 
  1562 * Proof terms: type substitutions on proof constants now use canonical
  1563 order of type variables.  INCOMPATIBILITY for tools working with proof
  1564 terms.
  1565 
  1566 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1567 may no longer carry premises.  User-level specifications are
  1568 transformed accordingly by Thm.add_axiom/add_def.
  1569 
  1570 
  1571 *** System ***
  1572 
  1573 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1574 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1575 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1576 
  1577 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1578 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1579 respectively.
  1580 
  1581 * Old lib/scripts/polyml-platform is superseded by the
  1582 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1583 variant, even on a 64 bit machine.  The following example setting
  1584 prefers 64 bit if available:
  1585 
  1586   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1587 
  1588 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1589 Isabelle/Scala layer for advanced prover interaction and integration.
  1590 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1591 component.
  1592 
  1593 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1594 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1595 similar to the default assignment of the document preparation system
  1596 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1597 provides some operations for direct access to the font without asking
  1598 the user for manual installation.
  1599 
  1600 
  1601 
  1602 New in Isabelle2009-1 (December 2009)
  1603 -------------------------------------
  1604 
  1605 *** General ***
  1606 
  1607 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1608 one backslash should be used, even in ML sources.
  1609 
  1610 
  1611 *** Pure ***
  1612 
  1613 * Locale interpretation propagates mixins along the locale hierarchy.
  1614 The currently only available mixins are the equations used to map
  1615 local definitions to terms of the target domain of an interpretation.
  1616 
  1617 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1618 loc" to print all interpretations of locale "loc" in the theory.
  1619 Interpretations in proofs are not shown.
  1620 
  1621 * Thoroughly revised locales tutorial.  New section on conditional
  1622 interpretation.
  1623 
  1624 * On instantiation of classes, remaining undefined class parameters
  1625 are formally declared.  INCOMPATIBILITY.
  1626 
  1627 
  1628 *** Document preparation ***
  1629 
  1630 * New generalized style concept for printing terms: @{foo (style) ...}
  1631 instead of @{foo_style style ...}  (old form is still retained for
  1632 backward compatibility).  Styles can be also applied for
  1633 antiquotations prop, term_type and typeof.
  1634 
  1635 
  1636 *** HOL ***
  1637 
  1638 * New proof method "smt" for a combination of first-order logic with
  1639 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1640 fixed-size bitvectors; there is also basic support for higher-order
  1641 features (esp. lambda abstractions).  It is an incomplete decision
  1642 procedure based on external SMT solvers using the oracle mechanism;
  1643 for the SMT solver Z3, this method is proof-producing.  Certificates
  1644 are provided to avoid calling the external solvers solely for
  1645 re-checking proofs.  Due to a remote SMT service there is no need for
  1646 installing SMT solvers locally.  See src/HOL/SMT.
  1647 
  1648 * New commands to load and prove verification conditions generated by
  1649 the Boogie program verifier or derived systems (e.g. the Verifying C
  1650 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1651 
  1652 * New counterexample generator tool 'nitpick' based on the Kodkod
  1653 relational model finder.  See src/HOL/Tools/Nitpick and
  1654 src/HOL/Nitpick_Examples.
  1655 
  1656 * New commands 'code_pred' and 'values' to invoke the predicate
  1657 compiler and to enumerate values of inductive predicates.
  1658 
  1659 * A tabled implementation of the reflexive transitive closure.
  1660 
  1661 * New implementation of quickcheck uses generic code generator;
  1662 default generators are provided for all suitable HOL types, records
  1663 and datatypes.  Old quickcheck can be re-activated importing theory
  1664 Library/SML_Quickcheck.
  1665 
  1666 * New testing tool Mirabelle for automated proof tools.  Applies
  1667 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1668 every proof step in a theory.  To be used in batch mode via the
  1669 "mirabelle" utility.
  1670 
  1671 * New proof method "sos" (sum of squares) for nonlinear real
  1672 arithmetic (originally due to John Harison). It requires theory
  1673 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1674 works well in practice on quantifier-free real arithmetic with +, -,
  1675 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1676 inequalities between polynomials.  It makes use of external
  1677 semidefinite programming solvers.  Method "sos" generates a
  1678 certificate that can be pasted into the proof thus avoiding the need
  1679 to call an external tool every time the proof is checked.  See
  1680 src/HOL/Library/Sum_Of_Squares.
  1681 
  1682 * New method "linarith" invokes existing linear arithmetic decision
  1683 procedure only.
  1684 
  1685 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1686 
  1687 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1688 Causes full type information to be output to the ATPs.  This slows
  1689 ATPs down considerably but eliminates a source of unsound "proofs"
  1690 that fail later.
  1691 
  1692 * New method "metisFT": A version of metis that uses full type
  1693 information in order to avoid failures of proof reconstruction.
  1694 
  1695 * New evaluator "approximate" approximates an real valued term using
  1696 the same method as the approximation method.
  1697 
  1698 * Method "approximate" now supports arithmetic expressions as
  1699 boundaries of intervals and implements interval splitting and Taylor
  1700 series expansion.
  1701 
  1702 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1703 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1704 
  1705 * New theory SupInf of the supremum and infimum operators for sets of
  1706 reals.
  1707 
  1708 * New theory Probability, which contains a development of measure
  1709 theory, eventually leading to Lebesgue integration and probability.
  1710 
  1711 * Extended Multivariate Analysis to include derivation and Brouwer's
  1712 fixpoint theorem.
  1713 
  1714 * Reorganization of number theory, INCOMPATIBILITY:
  1715   - new number theory development for nat and int, in theories Divides
  1716     and GCD as well as in new session Number_Theory
  1717   - some constants and facts now suffixed with _nat and _int
  1718     accordingly
  1719   - former session NumberTheory now named Old_Number_Theory, including
  1720     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1721   - moved theory Pocklington from src/HOL/Library to
  1722     src/HOL/Old_Number_Theory
  1723 
  1724 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1725 lcm of finite and infinite sets. It is shown that they form a complete
  1726 lattice.
  1727 
  1728 * Class semiring_div requires superclass no_zero_divisors and proof of
  1729 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1730 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1731 generalized to class semiring_div, subsuming former theorems
  1732 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1733 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1734 INCOMPATIBILITY.
  1735 
  1736 * Refinements to lattice classes and sets:
  1737   - less default intro/elim rules in locale variant, more default
  1738     intro/elim rules in class variant: more uniformity
  1739   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1740     le_inf_iff
  1741   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1742     sup_aci)
  1743   - renamed ACI to inf_sup_aci
  1744   - new class "boolean_algebra"
  1745   - class "complete_lattice" moved to separate theory
  1746     "Complete_Lattice"; corresponding constants (and abbreviations)
  1747     renamed and with authentic syntax:
  1748     Set.Inf ~>    Complete_Lattice.Inf
  1749     Set.Sup ~>    Complete_Lattice.Sup
  1750     Set.INFI ~>   Complete_Lattice.INFI
  1751     Set.SUPR ~>   Complete_Lattice.SUPR
  1752     Set.Inter ~>  Complete_Lattice.Inter
  1753     Set.Union ~>  Complete_Lattice.Union
  1754     Set.INTER ~>  Complete_Lattice.INTER
  1755     Set.UNION ~>  Complete_Lattice.UNION
  1756   - authentic syntax for
  1757     Set.Pow
  1758     Set.image
  1759   - mere abbreviations:
  1760     Set.empty               (for bot)
  1761     Set.UNIV                (for top)
  1762     Set.inter               (for inf, formerly Set.Int)
  1763     Set.union               (for sup, formerly Set.Un)
  1764     Complete_Lattice.Inter  (for Inf)
  1765     Complete_Lattice.Union  (for Sup)
  1766     Complete_Lattice.INTER  (for INFI)
  1767     Complete_Lattice.UNION  (for SUPR)
  1768   - object-logic definitions as far as appropriate
  1769 
  1770 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1771 Un_subset_iff are explicitly deleted as default simp rules; then also
  1772 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1773 deleted to achieve the desired effect.
  1774 
  1775 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1776 rules by default any longer; the same applies to min_max.inf_absorb1
  1777 etc.  INCOMPATIBILITY.
  1778 
  1779 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1780 pred_set_conv by default.  INCOMPATIBILITY.
  1781 
  1782 * Power operations on relations and functions are now one dedicated
  1783 constant "compow" with infix syntax "^^".  Power operation on
  1784 multiplicative monoids retains syntax "^" and is now defined generic
  1785 in class power.  INCOMPATIBILITY.
  1786 
  1787 * Relation composition "R O S" now has a more standard argument order:
  1788 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1789 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1790 break, since the O_assoc rule was not rewritten like this.  Fix using
  1791 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1792 
  1793 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1794 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1795 INCOMPATIBILITY.
  1796 
  1797 * Most rules produced by inductive and datatype package have mandatory
  1798 prefixes.  INCOMPATIBILITY.
  1799 
  1800 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1801 the attribute of the same name.  Each of the theorems in the list
  1802 DERIV_intros assumes composition with an additional function and
  1803 matches a variable to the derivative, which has to be solved by the
  1804 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1805 of most elementary terms.  Former Maclauren.DERIV_tac and
  1806 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1807 INCOMPATIBILITY.
  1808 
  1809 * Code generator attributes follow the usual underscore convention:
  1810     code_unfold     replaces    code unfold
  1811     code_post       replaces    code post
  1812     etc.
  1813   INCOMPATIBILITY.
  1814 
  1815 * Renamed methods:
  1816     sizechange -> size_change
  1817     induct_scheme -> induction_schema
  1818   INCOMPATIBILITY.
  1819 
  1820 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1821 INCOMPATIBILITY, use "undefined" directly.
  1822 
  1823 * Renamed theorems:
  1824     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1825     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1826     Suc_plus1 -> Suc_eq_plus1
  1827     *anti_sym -> *antisym*
  1828     vector_less_eq_def -> vector_le_def
  1829   INCOMPATIBILITY.
  1830 
  1831 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1832 INCOMPATIBILITY.
  1833 
  1834 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1835 INCOMPATIBILITY.
  1836 
  1837 
  1838 *** HOLCF ***
  1839 
  1840 * Theory Representable defines a class "rep" of domains that are
  1841 representable (via an ep-pair) in the universal domain type "udom".
  1842 Instances are provided for all type constructors defined in HOLCF.
  1843 
  1844 * The 'new_domain' command is a purely definitional version of the
  1845 domain package, for representable domains.  Syntax is identical to the
  1846 old domain package.  The 'new_domain' package also supports indirect
  1847 recursion using previously-defined type constructors.  See
  1848 src/HOLCF/ex/New_Domain.thy for examples.
  1849 
  1850 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1851 on the left-hand side of an equation, and then performs
  1852 simplification.  Rewriting is done using rules declared with the
  1853 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1854 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1855 
  1856 * The pattern-match compiler in 'fixrec' can now handle constructors
  1857 with HOL function types.  Pattern-match combinators for the Pair
  1858 constructor are pre-configured.
  1859 
  1860 * The 'fixrec' package now produces better fixed-point induction rules
  1861 for mutually-recursive definitions:  Induction rules have conclusions
  1862 of the form "P foo bar" instead of "P <foo, bar>".
  1863 
  1864 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1865 been renamed to "below".  The name "below" now replaces "less" in many
  1866 theorem names.  (Legacy theorem names using "less" are still supported
  1867 as well.)
  1868 
  1869 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1870 patterns can be used to generate strictness rules, or to make
  1871 functions more strict (much like the bang-patterns supported by the
  1872 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1873 examples.
  1874 
  1875 
  1876 *** ML ***
  1877 
  1878 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1879 errors and run-time exceptions, including detailed source positions.
  1880 
  1881 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1882 identified entries, with some additional information such as source
  1883 position, logical grouping etc.
  1884 
  1885 * Theory and context data is now introduced by the simplified and
  1886 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1887 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1888 copy operation) is still available for some time.
  1889 
  1890 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1891 provides a high-level programming interface to synchronized state
  1892 variables with atomic update.  This works via pure function
  1893 application within a critical section -- its runtime should be as
  1894 short as possible; beware of deadlocks if critical code is nested,
  1895 either directly or indirectly via other synchronized variables!
  1896 
  1897 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1898 wraps raw ML references, explicitly indicating their non-thread-safe
  1899 behaviour.  The Isar toplevel keeps this structure open, to
  1900 accommodate Proof General as well as quick and dirty interactive
  1901 experiments with references.
  1902 
  1903 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1904 parallel tactical reasoning.
  1905 
  1906 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1907 are similar to SUBPROOF, but are slightly more flexible: only the
  1908 specified parts of the subgoal are imported into the context, and the
  1909 body tactic may introduce new subgoals and schematic variables.
  1910 
  1911 * Old tactical METAHYPS, which does not observe the proof context, has
  1912 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1913 or Subgoal.FOCUS etc.
  1914 
  1915 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1916 functors have their own ML name space there is no point to mark them
  1917 separately.)  Minor INCOMPATIBILITY.
  1918 
  1919 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1920 
  1921 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1922 INCOMPATIBILITY.
  1923 
  1924 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1925 mode, which avoids critical setmp.
  1926 
  1927 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1928 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1929 Attrib/Method.setup introduced in Isabelle2009.
  1930 
  1931 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1932 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1933 last resort.  INCOMPATIBILITY.
  1934 
  1935 * Display.pretty_thm now requires a proper context (cf. former
  1936 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1937 or even Display.pretty_thm_without_context as last resort.
  1938 INCOMPATIBILITY.
  1939 
  1940 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1941 Syntax.pretty_typ/term directly, preferably with proper context
  1942 instead of global theory.
  1943 
  1944 
  1945 *** System ***
  1946 
  1947 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1948 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1949 usedir option -q.
  1950 
  1951 * Support for additional "Isabelle components" via etc/components, see
  1952 also the system manual.
  1953 
  1954 * The isabelle makeall tool now operates on all components with
  1955 IsaMakefile, not just hardwired "logics".
  1956 
  1957 * Removed "compress" option from isabelle-process and isabelle usedir;
  1958 this is always enabled.
  1959 
  1960 * Discontinued support for Poly/ML 4.x versions.
  1961 
  1962 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  1963 on a given logic image.  This requires the lighttpd webserver and is
  1964 currently supported on Linux only.
  1965 
  1966 
  1967 
  1968 New in Isabelle2009 (April 2009)
  1969 --------------------------------
  1970 
  1971 *** General ***
  1972 
  1973 * Simplified main Isabelle executables, with less surprises on
  1974 case-insensitive file-systems (such as Mac OS).
  1975 
  1976   - The main Isabelle tool wrapper is now called "isabelle" instead of
  1977     "isatool."
  1978 
  1979   - The former "isabelle" alias for "isabelle-process" has been
  1980     removed (should rarely occur to regular users).
  1981 
  1982   - The former "isabelle-interface" and its alias "Isabelle" have been
  1983     removed (interfaces are now regular Isabelle tools).
  1984 
  1985 Within scripts and make files, the Isabelle environment variables
  1986 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  1987 respectively.  (The latter are still available as legacy feature.)
  1988 
  1989 The old isabelle-interface wrapper could react in confusing ways if
  1990 the interface was uninstalled or changed otherwise.  Individual
  1991 interface tool configuration is now more explicit, see also the
  1992 Isabelle system manual.  In particular, Proof General is now available
  1993 via "isabelle emacs".
  1994 
  1995 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  1996 purge installed copies of Isabelle executables and re-run "isabelle
  1997 install -p ...", or use symlinks.
  1998 
  1999 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  2000 old ~/isabelle, which was slightly non-standard and apt to cause
  2001 surprises on case-insensitive file-systems (such as Mac OS).
  2002 
  2003 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  2004 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  2005 care is required when using older releases of Isabelle.  Note that
  2006 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  2007 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  2008 
  2009 * Proofs of fully specified statements are run in parallel on
  2010 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  2011 a regular 4-core machine, if the initial heap space is made reasonably
  2012 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  2013 
  2014 * The main reference manuals ("isar-ref", "implementation", and
  2015 "system") have been updated and extended.  Formally checked references
  2016 as hyperlinks are now available uniformly.
  2017 
  2018 
  2019 *** Pure ***
  2020 
  2021 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  2022 respects.  The most important changes are listed below.  See the
  2023 Tutorial on Locales ("locales" manual) for details.
  2024 
  2025 - In locale expressions, instantiation replaces renaming.  Parameters
  2026 must be declared in a for clause.  To aid compatibility with previous
  2027 parameter inheritance, in locale declarations, parameters that are not
  2028 'touched' (instantiation position "_" or omitted) are implicitly added
  2029 with their syntax at the beginning of the for clause.
  2030 
  2031 - Syntax from abbreviations and definitions in locales is available in
  2032 locale expressions and context elements.  The latter is particularly
  2033 useful in locale declarations.
  2034 
  2035 - More flexible mechanisms to qualify names generated by locale
  2036 expressions.  Qualifiers (prefixes) may be specified in locale
  2037 expressions, and can be marked as mandatory (syntax: "name!:") or
  2038 optional (syntax "name?:").  The default depends for plain "name:"
  2039 depends on the situation where a locale expression is used: in
  2040 commands 'locale' and 'sublocale' prefixes are optional, in
  2041 'interpretation' and 'interpret' prefixes are mandatory.  The old
  2042 implicit qualifiers derived from the parameter names of a locale are
  2043 no longer generated.
  2044 
  2045 - Command "sublocale l < e" replaces "interpretation l < e".  The
  2046 instantiation clause in "interpretation" and "interpret" (square
  2047 brackets) is no longer available.  Use locale expressions.
  2048 
  2049 - When converting proof scripts, mandatory qualifiers in
  2050 'interpretation' and 'interpret' should be retained by default, even
  2051 if this is an INCOMPATIBILITY compared to former behavior.  In the
  2052 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  2053 in locale expressions range over a single locale instance only.
  2054 
  2055 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  2056 In existing theorem specifications replace the includes element by the
  2057 respective context elements of the included locale, omitting those
  2058 that are already present in the theorem specification.  Multiple
  2059 assume elements of a locale should be replaced by a single one
  2060 involving the locale predicate.  In the proof body, declarations (most
  2061 notably theorems) may be regained by interpreting the respective
  2062 locales in the proof context as required (command "interpret").
  2063 
  2064 If using "includes" in replacement of a target solely because the
  2065 parameter types in the theorem are not as general as in the target,
  2066 consider declaring a new locale with additional type constraints on
  2067 the parameters (context element "constrains").
  2068 
  2069 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2070 
  2071 - Locale interpretation commands no longer attempt to simplify goal.
  2072 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2073 methods intro_locales and unfold_locales to clarify.
  2074 
  2075 - Locale interpretation commands no longer accept interpretation
  2076 attributes.  INCOMPATIBILITY.
  2077 
  2078 * Class declaration: so-called "base sort" must not be given in import
  2079 list any longer, but is inferred from the specification.  Particularly
  2080 in HOL, write
  2081 
  2082     class foo = ...
  2083 
  2084 instead of
  2085 
  2086     class foo = type + ...
  2087 
  2088 * Class target: global versions of theorems stemming do not carry a
  2089 parameter prefix any longer.  INCOMPATIBILITY.
  2090 
  2091 * Class 'instance' command no longer accepts attached definitions.
  2092 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2093 
  2094 * Recovered hiding of consts, which was accidentally broken in
  2095 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2096 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2097 
  2098 * Slightly more coherent Pure syntax, with updated documentation in
  2099 isar-ref manual.  Removed locales meta_term_syntax and
  2100 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2101 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2102 directly in regular applications.
  2103 
  2104 * There is a new syntactic category "float_const" for signed decimal
  2105 fractions (e.g. 123.45 or -123.45).
  2106 
  2107 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2108 interface with 'setup' command instead.
  2109 
  2110 * Command 'local_setup' is similar to 'setup', but operates on a local
  2111 theory context.
  2112 
  2113 * The 'axiomatization' command now only works within a global theory
  2114 context.  INCOMPATIBILITY.
  2115 
  2116 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2117 hypotheses.  Sorts required in the course of reasoning need to be
  2118 covered by the constraints in the initial statement, completed by the
  2119 type instance information of the background theory.  Non-trivial sort
  2120 hypotheses, which rarely occur in practice, may be specified via
  2121 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2122 
  2123   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2124 
  2125 The result contains an implicit sort hypotheses as before --
  2126 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2127 normalization.
  2128 
  2129 * Generalized Isar history, with support for linear undo, direct state
  2130 addressing etc.
  2131 
  2132 * Changed defaults for unify configuration options:
  2133 
  2134   unify_trace_bound = 50 (formerly 25)
  2135   unify_search_bound = 60 (formerly 30)
  2136 
  2137 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2138 
  2139   a) On theory merge, the last set of code equations for a particular
  2140      constant is taken (in accordance with the policy applied by other
  2141      parts of the code generator framework).
  2142 
  2143   b) Code equations stemming from explicit declarations (e.g. code
  2144      attribute) gain priority over default code equations stemming
  2145      from definition, primrec, fun etc.
  2146 
  2147 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2148 
  2149 * Unified theorem tables for both code generators.  Thus [code
  2150 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2151 
  2152 * Command 'find_consts' searches for constants based on type and name
  2153 patterns, e.g.
  2154 
  2155     find_consts "_ => bool"
  2156 
  2157 By default, matching is against subtypes, but it may be restricted to
  2158 the whole type.  Searching by name is possible.  Multiple queries are
  2159 conjunctive and queries may be negated by prefixing them with a
  2160 hyphen:
  2161 
  2162     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2163 
  2164 * New 'find_theorems' criterion "solves" matches theorems that
  2165 directly solve the current goal (modulo higher-order unification).
  2166 
  2167 * Auto solve feature for main theorem statements: whenever a new goal
  2168 is stated, "find_theorems solves" is called; any theorems that could
  2169 solve the lemma directly are listed as part of the goal state.
  2170 Cf. associated options in Proof General Isabelle settings menu,
  2171 enabled by default, with reasonable timeout for pathological cases of
  2172 higher-order unification.
  2173 
  2174 
  2175 *** Document preparation ***
  2176 
  2177 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2178 demanding keyword 'by' and supporting the full method expression
  2179 syntax just like the Isar command 'by'.
  2180 
  2181 
  2182 *** HOL ***
  2183 
  2184 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2185 points Main and Complex_Main remain as before.
  2186 
  2187 * Logic image HOL-Plain provides a minimal HOL with the most important
  2188 tools available (inductive, datatype, primrec, ...).  This facilitates
  2189 experimentation and tool development.  Note that user applications
  2190 (and library theories) should never refer to anything below theory
  2191 Main, as before.
  2192 
  2193 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2194 experimentation due to shorter build times.
  2195 
  2196 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2197 were previously part of former HOL-Complex.  Entry point Hyperreal
  2198 remains valid, but theories formerly using Complex_Main should now use
  2199 new entry point Hypercomplex.
  2200 
  2201 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2202 Posix processes.  Avoids potentially expensive forking of the ML
  2203 process.  New thread-based implementation also works on non-Unix
  2204 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2205 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2206 commands are covered in the isar-ref manual.
  2207 
  2208 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2209 sledgehammer without local ATP installation (Vampire etc.). Other
  2210 provers may be included via suitable ML wrappers, see also
  2211 src/HOL/ATP_Linkup.thy.
  2212 
  2213 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2214 menu.
  2215 
  2216 * The metis method no longer fails because the theorem is too trivial
  2217 (contains the empty clause).
  2218 
  2219 * The metis method now fails in the usual manner, rather than raising
  2220 an exception, if it determines that it cannot prove the theorem.
  2221 
  2222 * Method "coherent" implements a prover for coherent logic (see also
  2223 src/Tools/coherent.ML).
  2224 
  2225 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2226 "undefined" is the right choice to replace "arbitrary", though
  2227 logically there is no difference.  INCOMPATIBILITY.
  2228 
  2229 * Command "value" now integrates different evaluation mechanisms.  The
  2230 result of the first successful evaluation mechanism is printed.  In
  2231 square brackets a particular named evaluation mechanisms may be
  2232 specified (currently, [SML], [code] or [nbe]).  See further
  2233 src/HOL/ex/Eval_Examples.thy.
  2234 
  2235 * Normalization by evaluation now allows non-leftlinear equations.
  2236 Declare with attribute [code nbe].
  2237 
  2238 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2239 as the structured Isar versions "cases" and "induct", cf. the
  2240 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2241 are now presented as a list of individual projections
  2242 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2243 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2244 rare situations a different rule is selected --- notably nested tuple
  2245 elimination instead of former prod.exhaust: use explicit (case_tac t
  2246 rule: prod.exhaust) here.
  2247 
  2248 * Attributes "cases", "induct", "coinduct" support "del" option.
  2249 
  2250 * Removed fact "case_split_thm", which duplicates "case_split".
  2251 
  2252 * The option datatype has been moved to a new theory Option.  Renamed
  2253 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2254 
  2255 * New predicate "strict_mono" classifies strict functions on partial
  2256 orders.  With strict functions on linear orders, reasoning about
  2257 (in)equalities is facilitated by theorems "strict_mono_eq",
  2258 "strict_mono_less_eq" and "strict_mono_less".
  2259 
  2260 * Some set operations are now proper qualified constants with
  2261 authentic syntax.  INCOMPATIBILITY:
  2262 
  2263     op Int ~>   Set.Int
  2264     op Un ~>    Set.Un
  2265     INTER ~>    Set.INTER
  2266     UNION ~>    Set.UNION
  2267     Inter ~>    Set.Inter
  2268     Union ~>    Set.Union
  2269     {} ~>       Set.empty
  2270     UNIV ~>     Set.UNIV
  2271 
  2272 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2273 theory Set.
  2274 
  2275 * Auxiliary class "itself" has disappeared -- classes without any
  2276 parameter are treated as expected by the 'class' command.
  2277 
  2278 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2279 
  2280 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2281 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2282 
  2283 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2284 method "approximation".  It proves formulas on real values by using
  2285 interval arithmetic.  In the formulas are also the transcendental
  2286 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2287 allowed. For examples see
  2288 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2289 
  2290 * Theory "Reflection" now resides in HOL/Library.
  2291 
  2292 * Entry point to Word library now simply named "Word".
  2293 INCOMPATIBILITY.
  2294 
  2295 * Made source layout more coherent with logical distribution
  2296 structure:
  2297 
  2298     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2299     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2300     src/HOL/Library/GCD.thy ~> src/HOL/
  2301     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2302     src/HOL/Library/Parity.thy ~> src/HOL/
  2303     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2304     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2305     src/HOL/Real/Lubs.thy ~> src/HOL/
  2306     src/HOL/Real/PReal.thy ~> src/HOL/
  2307     src/HOL/Real/Rational.thy ~> src/HOL/
  2308     src/HOL/Real/RComplete.thy ~> src/HOL/
  2309     src/HOL/Real/RealDef.thy ~> src/HOL/
  2310     src/HOL/Real/RealPow.thy ~> src/HOL/
  2311     src/HOL/Real/Real.thy ~> src/HOL/
  2312     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2313     src/HOL/Complex/Complex.thy ~> src/HOL/
  2314     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2315     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2316     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2317     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2318     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2319     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2320     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2321     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2322     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2323     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2324     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2325     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2326     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2327     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2328     src/HOL/Real/Float ~> src/HOL/Library/
  2329     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2330     src/HOL/Real/RealVector.thy ~> src/HOL/
  2331 
  2332     src/HOL/arith_data.ML ~> src/HOL/Tools
  2333     src/HOL/hologic.ML ~> src/HOL/Tools
  2334     src/HOL/simpdata.ML ~> src/HOL/Tools
  2335     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2336     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2337     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2338     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2339     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2340     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2341     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2342 
  2343     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2344     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2345     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2346     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2347     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2348     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2349 
  2350 * If methods "eval" and "evaluation" encounter a structured proof
  2351 state with !!/==>, only the conclusion is evaluated to True (if
  2352 possible), avoiding strange error messages.
  2353 
  2354 * Method "sizechange" automates termination proofs using (a
  2355 modification of) the size-change principle.  Requires SAT solver.  See
  2356 src/HOL/ex/Termination.thy for examples.
  2357 
  2358 * Simplifier: simproc for let expressions now unfolds if bound
  2359 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2360 
  2361 * Method "arith": Linear arithmetic now ignores all inequalities when
  2362 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2363 
  2364 * New attribute "arith" for facts that should always be used
  2365 automatically by arithmetic. It is intended to be used locally in
  2366 proofs, e.g.
  2367 
  2368   assumes [arith]: "x > 0"
  2369 
  2370 Global usage is discouraged because of possible performance impact.
  2371 
  2372 * New classes "top" and "bot" with corresponding operations "top" and
  2373 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2374 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2375 
  2376 * Changed definition lemma "less_fun_def" in order to provide an
  2377 instance for preorders on functions; use lemma "less_le" instead.
  2378 INCOMPATIBILITY.
  2379 
  2380 * Theory Orderings: class "wellorder" moved here, with explicit
  2381 induction rule "less_induct" as assumption.  For instantiation of
  2382 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2383 INCOMPATIBILITY.
  2384 
  2385 * Theory Orderings: added class "preorder" as superclass of "order".
  2386 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2387 etc. slightly changed.  Some theorems named order_class.* now named
  2388 preorder_class.*.
  2389 
  2390 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2391 "diag" to "Id_on".
  2392 
  2393 * Theory Finite_Set: added a new fold combinator of type
  2394 
  2395   ('a => 'b => 'b) => 'b => 'a set => 'b
  2396 
  2397 Occasionally this is more convenient than the old fold combinator
  2398 which is now defined in terms of the new one and renamed to
  2399 fold_image.
  2400 
  2401 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2402 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2403 extended with further lemmas!).  At the moment both still exist but
  2404 the former will disappear at some point.
  2405 
  2406 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2407 class recpower.  Type-specific simp rules for various recpower types
  2408 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2409 
  2410 rat_power_0    -> power_0
  2411 rat_power_Suc  -> power_Suc
  2412 realpow_0      -> power_0
  2413 realpow_Suc    -> power_Suc
  2414 complexpow_0   -> power_0
  2415 complexpow_Suc -> power_Suc
  2416 power_poly_0   -> power_0
  2417 power_poly_Suc -> power_Suc
  2418 
  2419 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2420 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2421 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2422 of lemmas from Divides has been generalized from nat to class
  2423 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2424 renames resulting from duplicate elimination:
  2425 
  2426     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2427     zero_dvd_iff ~>         dvd_0_left_iff
  2428     dvd_0 ~>                dvd_0_right
  2429     DIVISION_BY_ZERO_DIV ~> div_by_0
  2430     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2431     mult_div ~>             div_mult_self2_is_id
  2432     mult_mod ~>             mod_mult_self2_is_0
  2433 
  2434 * Theory IntDiv: removed many lemmas that are instances of class-based
  2435 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2436 rename old lemmas as follows:
  2437 
  2438 dvd_diff               -> nat_dvd_diff
  2439 dvd_zminus_iff         -> dvd_minus_iff
  2440 mod_add1_eq            -> mod_add_eq
  2441 mod_mult1_eq           -> mod_mult_right_eq
  2442 mod_mult1_eq'          -> mod_mult_left_eq
  2443 mod_mult_distrib_mod   -> mod_mult_eq
  2444 nat_mod_add_left_eq    -> mod_add_left_eq
  2445 nat_mod_add_right_eq   -> mod_add_right_eq
  2446 nat_mod_div_trivial    -> mod_div_trivial
  2447 nat_mod_mod_trivial    -> mod_mod_trivial
  2448 zdiv_zadd_self1        -> div_add_self1
  2449 zdiv_zadd_self2        -> div_add_self2
  2450 zdiv_zmult_self1       -> div_mult_self2_is_id
  2451 zdiv_zmult_self2       -> div_mult_self1_is_id
  2452 zdvd_triv_left         -> dvd_triv_left
  2453 zdvd_triv_right        -> dvd_triv_right
  2454 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2455 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2456 zmod_zadd_left_eq      -> mod_add_left_eq
  2457 zmod_zadd_right_eq     -> mod_add_right_eq
  2458 zmod_zadd_self1        -> mod_add_self1
  2459 zmod_zadd_self2        -> mod_add_self2
  2460 zmod_zadd1_eq          -> mod_add_eq
  2461 zmod_zdiff1_eq         -> mod_diff_eq
  2462 zmod_zdvd_zmod         -> mod_mod_cancel
  2463 zmod_zmod_cancel       -> mod_mod_cancel
  2464 zmod_zmult_self1       -> mod_mult_self2_is_0
  2465 zmod_zmult_self2       -> mod_mult_self1_is_0
  2466 zmod_1                 -> mod_by_1
  2467 zdiv_1                 -> div_by_1
  2468 zdvd_abs1              -> abs_dvd_iff
  2469 zdvd_abs2              -> dvd_abs_iff
  2470 zdvd_refl              -> dvd_refl
  2471 zdvd_trans             -> dvd_trans
  2472 zdvd_zadd              -> dvd_add
  2473 zdvd_zdiff             -> dvd_diff
  2474 zdvd_zminus_iff        -> dvd_minus_iff
  2475 zdvd_zminus2_iff       -> minus_dvd_iff
  2476 zdvd_zmultD            -> dvd_mult_right
  2477 zdvd_zmultD2           -> dvd_mult_left
  2478 zdvd_zmult_mono        -> mult_dvd_mono
  2479 zdvd_0_right           -> dvd_0_right
  2480 zdvd_0_left            -> dvd_0_left_iff
  2481 zdvd_1_left            -> one_dvd
  2482 zminus_dvd_iff         -> minus_dvd_iff
  2483 
  2484 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2485 
  2486 * The real numbers offer decimal input syntax: 12.34 is translated
  2487 into 1234/10^2. This translation is not reversed upon output.
  2488 
  2489 * Theory Library/Polynomial defines an abstract type 'a poly of
  2490 univariate polynomials with coefficients of type 'a.  In addition to
  2491 the standard ring operations, it also supports div and mod.  Code
  2492 generation is also supported, using list-style constructors.
  2493 
  2494 * Theory Library/Inner_Product defines a class of real_inner for real
  2495 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2496 => real.  Class real_inner is a subclass of real_normed_vector from
  2497 theory RealVector.
  2498 
  2499 * Theory Library/Product_Vector provides instances for the product
  2500 type 'a * 'b of several classes from RealVector and Inner_Product.
  2501 Definitions of addition, subtraction, scalar multiplication, norms,
  2502 and inner products are included.
  2503 
  2504 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2505 addition to the field operations, numerals and case syntax are also
  2506 supported.
  2507 
  2508 * Theory Library/Diagonalize provides constructive version of Cantor's
  2509 first diagonalization argument.
  2510 
  2511 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2512 zlcm (for int); carried together from various gcd/lcm developements in
  2513 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2514 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2515 may recover tupled syntax as follows:
  2516 
  2517     hide (open) const gcd
  2518     abbreviation gcd where
  2519       "gcd == (%(a, b). GCD.gcd a b)"
  2520     notation (output)
  2521       GCD.gcd ("gcd '(_, _')")
  2522 
  2523 The same works for lcm, zgcd, zlcm.
  2524 
  2525 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2526 instantiations for algebraic structures.  Removed some duplicate
  2527 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2528 
  2529 * ML antiquotation @{code} takes a constant as argument and generates
  2530 corresponding code in background and inserts name of the corresponding
  2531 resulting ML value/function/datatype constructor binding in place.
  2532 All occurrences of @{code} with a single ML block are generated
  2533 simultaneously.  Provides a generic and safe interface for
  2534 instrumentalizing code generation.  See
  2535 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2536 In future you ought to refrain from ad-hoc compiling generated SML
  2537 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2538 cannot refer to constants for which user-defined serializations are
  2539 set.  Refer to the corresponding ML counterpart directly in that
  2540 cases.
  2541 
  2542 * Command 'rep_datatype': instead of theorem names the command now
  2543 takes a list of terms denoting the constructors of the type to be
  2544 represented as datatype.  The characteristic theorems have to be
  2545 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2546 have disappeared in favour of existing ones:
  2547 
  2548     unit_induct                 ~> unit.induct
  2549     prod_induct                 ~> prod.induct
  2550     sum_induct                  ~> sum.induct
  2551     Suc_Suc_eq                  ~> nat.inject
  2552     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2553 
  2554 
  2555 *** HOL-Algebra ***
  2556 
  2557 * New locales for orders and lattices where the equivalence relation
  2558 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2559 locales use a record structure with field eq for the equivalence.
  2560 
  2561 * New theory of factorial domains.
  2562 
  2563 * Units_l_inv and Units_r_inv are now simp rules by default.
  2564 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2565 and/or r_inv will now also require deletion of these lemmas.
  2566 
  2567 * Renamed the following theorems, INCOMPATIBILITY:
  2568 
  2569 UpperD ~> Upper_memD
  2570 LowerD ~> Lower_memD
  2571 least_carrier ~> least_closed
  2572 greatest_carrier ~> greatest_closed
  2573 greatest_Lower_above ~> greatest_Lower_below
  2574 one_zero ~> carrier_one_zero
  2575 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2576 
  2577 
  2578 *** HOL-Nominal ***
  2579 
  2580 * Nominal datatypes can now contain type-variables.
  2581 
  2582 * Commands 'nominal_inductive' and 'equivariance' work with local
  2583 theory targets.
  2584 
  2585 * Nominal primrec can now works with local theory targets and its
  2586 specification syntax now conforms to the general format as seen in
  2587 'inductive' etc.
  2588 
  2589 * Method "perm_simp" honours the standard simplifier attributes
  2590 (no_asm), (no_asm_use) etc.
  2591 
  2592 * The new predicate #* is defined like freshness, except that on the
  2593 left hand side can be a set or list of atoms.
  2594 
  2595 * Experimental command 'nominal_inductive2' derives strong induction
  2596 principles for inductive definitions.  In contrast to
  2597 'nominal_inductive', which can only deal with a fixed number of
  2598 binders, it can deal with arbitrary expressions standing for sets of
  2599 atoms to be avoided.  The only inductive definition we have at the
  2600 moment that needs this generalisation is the typing rule for Lets in
  2601 the algorithm W:
  2602 
  2603  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2604  -----------------------------------------------------------------
  2605          Gamma |- Let x be t1 in t2 : T2
  2606 
  2607 In this rule one wants to avoid all the binders that are introduced by
  2608 "close Gamma T1".  We are looking for other examples where this
  2609 feature might be useful.  Please let us know.
  2610 
  2611 
  2612 *** HOLCF ***
  2613 
  2614 * Reimplemented the simplification procedure for proving continuity
  2615 subgoals.  The new simproc is extensible; users can declare additional
  2616 continuity introduction rules with the attribute [cont2cont].
  2617 
  2618 * The continuity simproc now uses a different introduction rule for
  2619 solving continuity subgoals on terms with lambda abstractions.  In
  2620 some rare cases the new simproc may fail to solve subgoals that the
  2621 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2622 Potential INCOMPATIBILITY.
  2623 
  2624 * Command 'fixrec': specification syntax now conforms to the general
  2625 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2626 examples.  INCOMPATIBILITY.
  2627 
  2628 
  2629 *** ZF ***
  2630 
  2631 * Proof of Zorn's Lemma for partial orders.
  2632 
  2633 
  2634 *** ML ***
  2635 
  2636 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2637 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2638 depends on multithreading, so timouts will not work before Poly/ML
  2639 5.2.1!
  2640 
  2641 * High-level support for concurrent ML programming, see
  2642 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2643 particularly convenient to organize independent functional
  2644 computations.  The concept of "synchronized variables" provides a
  2645 higher-order interface for components with shared state, avoiding the
  2646 delicate details of mutexes and condition variables.  (Requires
  2647 Poly/ML 5.2.1 or later.)
  2648 
  2649 * ML bindings produced via Isar commands are stored within the Isar
  2650 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2651 become thread-safe and work with undo as expected (concerning
  2652 top-level bindings, not side-effects on global references).
  2653 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2654 compiler at runtime; really global bindings need to be given outside a
  2655 theory.  (Requires Poly/ML 5.2 or later.)
  2656 
  2657 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2658 context.  Top-level ML bindings are stored within the proof context in
  2659 a purely sequential fashion, disregarding the nested proof structure.
  2660 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2661 proof.  (Requires Poly/ML 5.2 or later.)
  2662 
  2663 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2664 and Method.setup, as well as Isar commands 'attribute_setup' and
  2665 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2666 existing code accordingly, or use plain 'setup' together with old
  2667 Method.add_method.
  2668 
  2669 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2670 to 'a -> thm, while results are always tagged with an authentic oracle
  2671 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2672 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2673 accordingly.  Note that extra performance may be gained by producing
  2674 the cterm carefully, avoiding slow Thm.cterm_of.
  2675 
  2676 * Simplified interface for defining document antiquotations via
  2677 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2678 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2679 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2680 examples.
  2681 
  2682 * More systematic treatment of long names, abstract name bindings, and
  2683 name space operations.  Basic operations on qualified names have been
  2684 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2685 Long_Name.append.  Old type bstring has been mostly replaced by
  2686 abstract type binding (see structure Binding), which supports precise
  2687 qualification by packages and local theory targets, as well as proper
  2688 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2689 bstring values into Binding.name, or better pass through abstract
  2690 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2691 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2692 
  2693 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2694 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2695 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2696 
  2697 * Disposed old type and term read functions (Sign.read_def_typ,
  2698 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2699 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2700 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2701 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2702 resort for legacy applications.
  2703 
  2704 * Disposed old declarations, tactics, tactic combinators that refer to
  2705 the simpset or claset of an implicit theory (such as Addsimps,
  2706 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2707 embedded ML text, or local_simpset_of with a proper context passed as
  2708 explicit runtime argument.
  2709 
  2710 * Rules and tactics that read instantiations (read_instantiate,
  2711 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2712 context, which is required for parsing and type-checking.  Moreover,
  2713 the variables are specified as plain indexnames, not string encodings
  2714 thereof.  INCOMPATIBILITY.
  2715 
  2716 * Generic Toplevel.add_hook interface allows to analyze the result of
  2717 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2718 for theorem dependency output of transactions resulting in a new
  2719 theory state.
  2720 
  2721 * ML antiquotations: block-structured compilation context indicated by
  2722 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2723 
  2724   @{binding name}                         - basic name binding
  2725   @{let ?pat = term}                      - term abbreviation (HO matching)
  2726   @{note name = fact}                     - fact abbreviation
  2727   @{thm fact}                             - singleton fact (with attributes)
  2728   @{thms fact}                            - general fact (with attributes)
  2729   @{lemma prop by method}                 - singleton goal
  2730   @{lemma prop by meth1 meth2}            - singleton goal
  2731   @{lemma prop1 ... propN by method}      - general goal
  2732   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2733   @{lemma (open) ...}                     - open derivation
  2734 
  2735 
  2736 *** System ***
  2737 
  2738 * The Isabelle "emacs" tool provides a specific interface to invoke
  2739 Proof General / Emacs, with more explicit failure if that is not
  2740 installed (the old isabelle-interface script silently falls back on
  2741 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2742 installation location of the Proof General distribution.
  2743 
  2744 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2745 the Isabelle process into a JVM/Scala application.  See
  2746 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2747 process wrapper has been discontinued.)
  2748 
  2749 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2750 
  2751 * Various status messages (with exact source position information) are
  2752 emitted, if proper markup print mode is enabled.  This allows
  2753 user-interface components to provide detailed feedback on internal
  2754 prover operations.
  2755 
  2756 
  2757 
  2758 New in Isabelle2008 (June 2008)
  2759 -------------------------------
  2760 
  2761 *** General ***
  2762 
  2763 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2764 and updated, with formally checked references as hyperlinks.
  2765 
  2766 * Theory loader: use_thy (and similar operations) no longer set the
  2767 implicit ML context, which was occasionally hard to predict and in
  2768 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2769 provides a proper context already.
  2770 
  2771 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2772 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2773 'use' within a theory file will do the job.
  2774 
  2775 * Name space merge now observes canonical order, i.e. the second space
  2776 is inserted into the first one, while existing entries in the first
  2777 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2778 swap theory imports.
  2779 
  2780 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2781 INCOMPATIBILITY in identifier syntax etc.
  2782 
  2783 * Outer syntax: string tokens no longer admit escaped white space,
  2784 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2785 white space without escapes.
  2786 
  2787 * Outer syntax: string tokens may contain arbitrary character codes
  2788 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2789 "foo_bar".
  2790 
  2791 
  2792 *** Pure ***
  2793 
  2794 * Context-dependent token translations.  Default setup reverts locally
  2795 fixed variables, and adds hilite markup for undeclared frees.
  2796 
  2797 * Unused theorems can be found using the new command 'unused_thms'.
  2798 There are three ways of invoking it:
  2799 
  2800 (1) unused_thms
  2801      Only finds unused theorems in the current theory.
  2802 
  2803 (2) unused_thms thy_1 ... thy_n -
  2804      Finds unused theorems in the current theory and all of its ancestors,
  2805      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2806 
  2807 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2808      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2809      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2810      their ancestors.
  2811 
  2812 In order to increase the readability of the list produced by
  2813 unused_thms, theorems that have been created by a particular instance
  2814 of a theory command such as 'inductive' or 'function' are considered
  2815 to belong to the same "group", meaning that if at least one theorem in
  2816 this group is used, the other theorems in the same group are no longer
  2817 reported as unused.  Moreover, if all theorems in the group are
  2818 unused, only one theorem in the group is displayed.
  2819 
  2820 Note that proof objects have to be switched on in order for
  2821 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2822 usually the case when using Proof General with the default settings).
  2823 
  2824 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2825 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2826 duplicate fact bindings, or even accidental fact duplications.  Note
  2827 that tools may maintain dynamically scoped facts systematically, using
  2828 PureThy.add_thms_dynamic.
  2829 
  2830 * Command 'hide' now allows to hide from "fact" name space as well.
  2831 
  2832 * Eliminated destructive theorem database, simpset, claset, and
  2833 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2834 update of theories within ML code.
  2835 
  2836 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2837 INCOMPATIBILITY, object-logics depending on former Pure require
  2838 additional setup PureThy.old_appl_syntax_setup; object-logics
  2839 depending on former CPure need to refer to Pure.
  2840 
  2841 * Commands 'use' and 'ML' are now purely functional, operating on
  2842 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2843 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2844 INCOMPATIBILITY.
  2845 
  2846 * Command 'setup': discontinued implicit version with ML reference.
  2847 
  2848 * Instantiation target allows for simultaneous specification of class
  2849 instance operations together with an instantiation proof.
  2850 Type-checking phase allows to refer to class operations uniformly.
  2851 See src/HOL/Complex/Complex.thy for an Isar example and
  2852 src/HOL/Library/Eval.thy for an ML example.
  2853 
  2854 * Indexing of literal facts: be more serious about including only
  2855 facts from the visible specification/proof context, but not the
  2856 background context (locale etc.).  Affects `prop` notation and method
  2857 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2858 situations.
  2859 
  2860 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2861 "(open)" option, which used to expose internal bound variables to the
  2862 proof text.
  2863 
  2864 * Isar statements: removed obsolete case "rule_context".
  2865 INCOMPATIBILITY, better use explicit fixes/assumes.
  2866 
  2867 * Locale proofs: default proof step now includes 'unfold_locales';
  2868 hence 'proof' without argument may be used to unfold locale
  2869 predicates.
  2870 
  2871 
  2872 *** Document preparation ***
  2873 
  2874 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2875 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2876 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2877 spot); renamed link color from "darkblue" to "linkcolor" (default
  2878 value unchanged, can be redefined via \definecolor); no longer sets
  2879 "a4paper" option (unnecessary or even intrusive).
  2880 
  2881 * Antiquotation @{lemma A method} proves proposition A by the given
  2882 method (either a method name or a method name plus (optional) method
  2883 arguments in parentheses) and prints A just like @{prop A}.
  2884 
  2885 
  2886 *** HOL ***
  2887 
  2888 * New primrec package.  Specification syntax conforms in style to
  2889 definition/function/....  No separate induction rule is provided.  The
  2890 "primrec" command distinguishes old-style and new-style specifications
  2891 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2892 When adjusting theories, beware: constants stemming from new-style
  2893 primrec specifications have authentic syntax.
  2894 
  2895 * Metis prover is now an order of magnitude faster, and also works
  2896 with multithreading.
  2897 
  2898 * Metis: the maximum number of clauses that can be produced from a
  2899 theorem is now given by the attribute max_clauses.  Theorems that
  2900 exceed this number are ignored, with a warning printed.
  2901 
  2902 * Sledgehammer no longer produces structured proofs by default. To
  2903 enable, declare [[sledgehammer_full = true]].  Attributes
  2904 reconstruction_modulus, reconstruction_sorts renamed
  2905 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2906 
  2907 * Method "induct_scheme" derives user-specified induction rules
  2908 from well-founded induction and completeness of patterns. This factors
  2909 out some operations that are done internally by the function package
  2910 and makes them available separately.  See
  2911 src/HOL/ex/Induction_Scheme.thy for examples.
  2912 
  2913 * More flexible generation of measure functions for termination
  2914 proofs: Measure functions can be declared by proving a rule of the
  2915 form "is_measure f" and giving it the [measure_function] attribute.
  2916 The "is_measure" predicate is logically meaningless (always true), and
  2917 just guides the heuristic.  To find suitable measure functions, the
  2918 termination prover sets up the goal "is_measure ?f" of the appropriate
  2919 type and generates all solutions by prolog-style backwards proof using
  2920 the declared rules.
  2921 
  2922 This setup also deals with rules like 
  2923 
  2924   "is_measure f ==> is_measure (list_size f)"
  2925 
  2926 which accommodates nested datatypes that recurse through lists.
  2927 Similar rules are predeclared for products and option types.
  2928 
  2929 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2930 
  2931   INCOMPATIBILITIES:
  2932 
  2933   - Definitions of overloaded constants on sets have to be replaced by
  2934     definitions on => and bool.
  2935 
  2936   - Some definitions of overloaded operators on sets can now be proved
  2937     using the definitions of the operators on => and bool.  Therefore,
  2938     the following theorems have been renamed:
  2939 
  2940       subset_def   -> subset_eq
  2941       psubset_def  -> psubset_eq
  2942       set_diff_def -> set_diff_eq
  2943       Compl_def    -> Compl_eq
  2944       Sup_set_def  -> Sup_set_eq
  2945       Inf_set_def  -> Inf_set_eq
  2946       sup_set_def  -> sup_set_eq
  2947       inf_set_def  -> inf_set_eq
  2948 
  2949   - Due to the incompleteness of the HO unification algorithm, some
  2950     rules such as subst may require manual instantiation, if some of
  2951     the unknowns in the rule is a set.
  2952 
  2953   - Higher order unification and forward proofs:
  2954     The proof pattern
  2955 
  2956       have "P (S::'a set)" <...>
  2957       then have "EX S. P S" ..
  2958 
  2959     no longer works (due to the incompleteness of the HO unification
  2960     algorithm) and must be replaced by the pattern
  2961 
  2962       have "EX S. P S"
  2963       proof
  2964         show "P S" <...>
  2965       qed
  2966 
  2967   - Calculational reasoning with subst (or similar rules):
  2968     The proof pattern
  2969 
  2970       have "P (S::'a set)" <...>
  2971       also have "S = T" <...>
  2972       finally have "P T" .
  2973 
  2974     no longer works (for similar reasons as the previous example) and
  2975     must be replaced by something like
  2976 
  2977       have "P (S::'a set)" <...>
  2978       moreover have "S = T" <...>
  2979       ultimately have "P T" by simp
  2980 
  2981   - Tactics or packages written in ML code:
  2982     Code performing pattern matching on types via
  2983 
  2984       Type ("set", [T]) => ...
  2985 
  2986     must be rewritten. Moreover, functions like strip_type or
  2987     binder_types no longer return the right value when applied to a
  2988     type of the form
  2989 
  2990       T1 => ... => Tn => U => bool
  2991 
  2992     rather than
  2993 
  2994       T1 => ... => Tn => U set
  2995 
  2996 * Merged theories Wellfounded_Recursion, Accessible_Part and
  2997 Wellfounded_Relations to theory Wellfounded.
  2998 
  2999 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  3000 
  3001 * Class finite no longer treats UNIV as class parameter.  Use class
  3002 enum from theory Library/Enum instead to achieve a similar effect.
  3003 INCOMPATIBILITY.
  3004 
  3005 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  3006 and "Cons".  INCOMPATIBILITY.
  3007 
  3008 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  3009 Potential INCOMPATIBILITY.
  3010 
  3011 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  3012 injective_fst_snd removed, use split_eta and prod_eqI instead.
  3013 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  3014 
  3015 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  3016 the same name in theory Orderings:
  3017 
  3018   less_trans
  3019   less_linear
  3020   le_imp_less_or_eq
  3021   le_less_trans
  3022   less_le_trans
  3023   less_not_sym
  3024   less_asym
  3025 
  3026 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  3027 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  3028 and different variable names.
  3029 
  3030 * Library/Option_ord.thy: Canonical order on option type.
  3031 
  3032 * Library/RBT.thy: Red-black trees, an efficient implementation of
  3033 finite maps.
  3034 
  3035 * Library/Countable.thy: Type class for countable types.
  3036 
  3037 * Theory Int: The representation of numerals has changed.  The infix
  3038 operator BIT and the bit datatype with constructors B0 and B1 have
  3039 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  3040 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  3041 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  3042 accordingly.
  3043 
  3044 * Theory Nat: definition of <= and < on natural numbers no longer
  3045 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  3046 le_def and less_def have disappeared.  Consider lemmas not_less
  3047 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  3048 
  3049 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  3050 (whose purpose mainly is for various fold_set functionals) have been
  3051 abandoned in favor of the existing algebraic classes
  3052 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  3053 lower_semilattice (resp. upper_semilattice) and linorder.
  3054 INCOMPATIBILITY.
  3055 
  3056 * Theory Transitive_Closure: induct and cases rules now declare proper
  3057 case_names ("base" and "step").  INCOMPATIBILITY.
  3058 
  3059 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  3060 lattices.  The form set-specific version is available as
  3061 Inductive.lfp_ordinal_induct_set.
  3062 
  3063 * Renamed theorems "power.simps" to "power_int.simps".
  3064 INCOMPATIBILITY.
  3065 
  3066 * Class semiring_div provides basic abstract properties of semirings
  3067 with division and modulo operations.  Subsumes former class dvd_mod.
  3068 
  3069 * Merged theories IntDef, Numeral and IntArith into unified theory
  3070 Int.  INCOMPATIBILITY.
  3071 
  3072 * Theory Library/Code_Index: type "index" now represents natural
  3073 numbers rather than integers.  INCOMPATIBILITY.
  3074 
  3075 * New class "uminus" with operation "uminus" (split of from class
  3076 "minus" which now only has operation "minus", binary).
  3077 INCOMPATIBILITY.
  3078 
  3079 * Constants "card", "internal_split", "option_map" now with authentic
  3080 syntax.  INCOMPATIBILITY.
  3081 
  3082 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3083 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3084 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3085 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3086 Sup_set_def, le_def, less_def, option_map_def now with object
  3087 equality.  INCOMPATIBILITY.
  3088 
  3089 * Records. Removed K_record, and replaced it by pure lambda term
  3090 %x. c. The simplifier setup is now more robust against eta expansion.
  3091 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3092 
  3093 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3094 
  3095 * Library/ListVector: new theory of arithmetic vector operations.
  3096 
  3097 * Library/Order_Relation: new theory of various orderings as sets of
  3098 pairs.  Defines preorders, partial orders, linear orders and
  3099 well-orders on sets and on types.
  3100 
  3101 
  3102 *** ZF ***
  3103 
  3104 * Renamed some theories to allow to loading both ZF and HOL in the
  3105 same session:
  3106 
  3107   Datatype  -> Datatype_ZF
  3108   Inductive -> Inductive_ZF
  3109   Int       -> Int_ZF
  3110   IntDiv    -> IntDiv_ZF
  3111   Nat       -> Nat_ZF
  3112   List      -> List_ZF
  3113   Main      -> Main_ZF
  3114 
  3115 INCOMPATIBILITY: ZF theories that import individual theories below
  3116 Main might need to be adapted.  Regular theory Main is still
  3117 available, as trivial extension of Main_ZF.
  3118 
  3119 
  3120 *** ML ***
  3121 
  3122 * ML within Isar: antiquotation @{const name} or @{const
  3123 name(typargs)} produces statically-checked Const term.
  3124 
  3125 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3126 (of the same name).  Removed obsolete print command.
  3127 
  3128 * Removed obsolete "use_legacy_bindings" function.
  3129 
  3130 * The ``print mode'' is now a thread-local value derived from a global
  3131 template (the former print_mode reference), thus access becomes
  3132 non-critical.  The global print_mode reference is for session
  3133 management only; user-code should use print_mode_value,
  3134 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3135 
  3136 * Functions system/system_out provide a robust way to invoke external
  3137 shell commands, with propagation of interrupts (requires Poly/ML
  3138 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3139 
  3140 
  3141 *** System ***
  3142 
  3143 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3144 in accordance with Proof General 3.7, which prefers GNU emacs.
  3145 
  3146 * isatool tty runs Isabelle process with plain tty interaction;
  3147 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3148 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3149 
  3150 * isatool browser now works with Cygwin as well, using general
  3151 "javapath" function defined in Isabelle process environment.
  3152 
  3153 * YXML notation provides a simple and efficient alternative to
  3154 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3155 isatool yxml as described in the Isabelle system manual.
  3156 
  3157 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3158 provides general wrapper for managing an Isabelle process in a robust
  3159 fashion, with ``cooked'' output from stdin/stderr.
  3160 
  3161 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3162 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3163 
  3164 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3165 way of changing the user's settings is via
  3166 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3167 script.
  3168 
  3169 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3170 cores of the underlying machine, which is a good starting point for
  3171 optimal performance tuning.  The corresponding usedir option -M allows
  3172 "max" as an alias for "0".  WARNING: does not work on certain versions
  3173 of Mac OS (with Poly/ML 5.1).
  3174 
  3175 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3176 adverse effect of Isabelle flooding interactive front-ends (notably
  3177 ProofGeneral / XEmacs).
  3178 
  3179 
  3180 
  3181 New in Isabelle2007 (November 2007)
  3182 -----------------------------------
  3183 
  3184 *** General ***
  3185 
  3186 * More uniform information about legacy features, notably a
  3187 warning/error of "Legacy feature: ...", depending on the state of the
  3188 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3189 legacy features will disappear eventually.
  3190 
  3191 * Theory syntax: the header format ``theory A = B + C:'' has been
  3192 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3193 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3194 
  3195 * Theory syntax: the old non-Isar theory file format has been
  3196 discontinued altogether.  Note that ML proof scripts may still be used
  3197 with Isar theories; migration is usually quite simple with the ML
  3198 function use_legacy_bindings.  INCOMPATIBILITY.
  3199 
  3200 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3201 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3202 quotes.
  3203 
  3204 * Theory loader: be more serious about observing the static theory
  3205 header specifications (including optional directories), but not the
  3206 accidental file locations of previously successful loads.  The strict
  3207 update policy of former update_thy is now already performed by
  3208 use_thy, so the former has been removed; use_thys updates several
  3209 theories simultaneously, just as 'imports' within a theory header
  3210 specification, but without merging the results.  Potential
  3211 INCOMPATIBILITY: may need to refine theory headers and commands
  3212 ROOT.ML which depend on load order.
  3213 
  3214 * Theory loader: optional support for content-based file
  3215 identification, instead of the traditional scheme of full physical
  3216 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3217 (cf. the system manual).  The new scheme allows to work with
  3218 non-finished theories in persistent session images, such that source
  3219 files may be moved later on without requiring reloads.
  3220 
  3221 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3222 file (with the same base name as the theory) are considered a legacy
  3223 feature, which will disappear eventually. Even now, the theory loader
  3224 no longer maintains dependencies on such files.
  3225 
  3226 * Syntax: the scope for resolving ambiguities via type-inference is
  3227 now limited to individual terms, instead of whole simultaneous
  3228 specifications as before. This greatly reduces the complexity of the
  3229 syntax module and improves flexibility by separating parsing and
  3230 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3231 'fixes' etc.) are required in rare situations.
  3232 
  3233 * Syntax: constants introduced by new-style packages ('definition',
  3234 'abbreviation' etc.) are passed through the syntax module in
  3235 ``authentic mode''. This means that associated mixfix annotations
  3236 really stick to such constants, independently of potential name space
  3237 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3238 trees are represented slightly differently, may need to adapt syntax
  3239 translations accordingly. Use CONST marker in 'translations' and
  3240 @{const_syntax} antiquotation in 'parse_translation' etc.
  3241 
  3242 * Legacy goal package: reduced interface to the bare minimum required
  3243 to keep existing proof scripts running.  Most other user-level
  3244 functions are now part of the OldGoals structure, which is *not* open
  3245 by default (consider isatool expandshort before open OldGoals).
  3246 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3247 these tend to cause confusion about the actual goal (!) context being
  3248 used here, which is not necessarily the same as the_context().
  3249 
  3250 * Command 'find_theorems': supports "*" wild-card in "name:"
  3251 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3252 support a specific search form (see ProofGeneral/CHANGES).
  3253 
  3254 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3255 by default, which means that "prems" (and also "fixed variables") are
  3256 suppressed from proof state output.  Note that the ProofGeneral
  3257 settings mechanism allows to change and save options persistently, but
  3258 older versions of Isabelle will fail to start up if a negative prems
  3259 limit is imposed.
  3260 
  3261 * Local theory targets may be specified by non-nested blocks of
  3262 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3263 contain definitions, theorems etc., including any derived mechanism
  3264 that has been implemented on top of these primitives.  This concept
  3265 generalizes the existing ``theorem (in ...)'' towards more versatility
  3266 and scalability.
  3267 
  3268 * Proof General interface: proper undo of final 'end' command;
  3269 discontinued Isabelle/classic mode (ML proof scripts).
  3270 
  3271 
  3272 *** Document preparation ***
  3273 
  3274 * Added antiquotation @{theory name} which prints the given name,
  3275 after checking that it refers to a valid ancestor theory in the
  3276 current context.
  3277 
  3278 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3279 check the given source text as ML type/structure, printing verbatim.
  3280 
  3281 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3282 "c args == rhs" given in the current context.  (Any number of
  3283 arguments may be given on the LHS.)
  3284 
  3285 
  3286 *** Pure ***
  3287 
  3288 * The 'class' package offers a combination of axclass and locale to
  3289 achieve Haskell-like type classes in Isabelle.  Definitions and
  3290 theorems within a class context produce both relative results (with
  3291 implicit parameters according to the locale context), and polymorphic
  3292 constants with qualified polymorphism (according to the class
  3293 context).  Within the body context of a 'class' target, a separate
  3294 syntax layer ("user space type system") takes care of converting
  3295 between global polymorphic consts and internal locale representation.
  3296 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3297 "isatool doc classes" provides a tutorial.
  3298 
  3299 * Generic code generator framework allows to generate executable
  3300 code for ML and Haskell (including Isabelle classes).  A short usage
  3301 sketch:
  3302 
  3303     internal compilation:
  3304         export_code <list of constants (term syntax)> in SML
  3305     writing SML code to a file:
  3306         export_code <list of constants (term syntax)> in SML <filename>
  3307     writing OCaml code to a file:
  3308         export_code <list of constants (term syntax)> in OCaml <filename>
  3309     writing Haskell code to a bunch of files:
  3310         export_code <list of constants (term syntax)> in Haskell <filename>
  3311 
  3312     evaluating closed propositions to True/False using code generation:
  3313         method ``eval''
  3314 
  3315 Reasonable default setup of framework in HOL.
  3316 
  3317 Theorem attributs for selecting and transforming function equations theorems:
  3318 
  3319     [code fun]:        select a theorem as function equation for a specific constant
  3320     [code fun del]:    deselect a theorem as function equation for a specific constant
  3321     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3322     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3323 
  3324 User-defined serializations (target in {SML, OCaml, Haskell}):
  3325 
  3326     code_const <and-list of constants (term syntax)>
  3327       {(target) <and-list of const target syntax>}+
  3328 
  3329     code_type <and-list of type constructors>
  3330       {(target) <and-list of type target syntax>}+
  3331 
  3332     code_instance <and-list of instances>
  3333       {(target)}+
  3334         where instance ::= <type constructor> :: <class>
  3335 
  3336     code_class <and_list of classes>
  3337       {(target) <and-list of class target syntax>}+
  3338         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3339 
  3340 code_instance and code_class only are effective to target Haskell.
  3341 
  3342 For example usage see src/HOL/ex/Codegenerator.thy and
  3343 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3344 generation from Isabelle/HOL theories is available via "isatool doc
  3345 codegen".
  3346 
  3347 * Code generator: consts in 'consts_code' Isar commands are now
  3348 referred to by usual term syntax (including optional type
  3349 annotations).
  3350 
  3351 * Command 'no_translations' removes translation rules from theory
  3352 syntax.
  3353 
  3354 * Overloaded definitions are now actually checked for acyclic
  3355 dependencies.  The overloading scheme is slightly more general than
  3356 that of Haskell98, although Isabelle does not demand an exact
  3357 correspondence to type class and instance declarations.
  3358 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3359 exotic versions of overloading -- at the discretion of the user!
  3360 
  3361 Polymorphic constants are represented via type arguments, i.e. the
  3362 instantiation that matches an instance against the most general
  3363 declaration given in the signature.  For example, with the declaration
  3364 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3365 as c(nat).  Overloading is essentially simultaneous structural
  3366 recursion over such type arguments.  Incomplete specification patterns
  3367 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3368 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3369 Command 'print_theory' outputs the normalized system of recursive
  3370 equations, see section "definitions".
  3371 
  3372 * Configuration options are maintained within the theory or proof
  3373 context (with name and type bool/int/string), providing a very simple
  3374 interface to a poor-man's version of general context data.  Tools may
  3375 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3376 these values using Config.get etc.  Users may change options via an
  3377 associated attribute of the same name.  This form of context
  3378 declaration works particularly well with commands 'declare' or
  3379 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3380 very easy to avoid global references, which would not observe Isar
  3381 toplevel undo/redo and fail to work with multithreading.
  3382 
  3383 Various global ML references of Pure and HOL have been turned into
  3384 configuration options:
  3385 
  3386   Unify.search_bound		unify_search_bound
  3387   Unify.trace_bound		unify_trace_bound
  3388   Unify.trace_simp		unify_trace_simp
  3389   Unify.trace_types		unify_trace_types
  3390   Simplifier.simp_depth_limit	simp_depth_limit
  3391   Blast.depth_limit		blast_depth_limit
  3392   DatatypeProp.dtK		datatype_distinctness_limit
  3393   fast_arith_neq_limit  	fast_arith_neq_limit
  3394   fast_arith_split_limit	fast_arith_split_limit
  3395 
  3396 * Named collections of theorems may be easily installed as context
  3397 data using the functor NamedThmsFun (see also
  3398 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3399 attributes; there is also a toplevel print command.  This facility is
  3400 just a common case of general context data, which is the preferred way
  3401 for anything more complex than just a list of facts in canonical
  3402 order.
  3403 
  3404 * Isar: command 'declaration' augments a local theory by generic
  3405 declaration functions written in ML.  This enables arbitrary content
  3406 being added to the context, depending on a morphism that tells the
  3407 difference of the original declaration context wrt. the application
  3408 context encountered later on.
  3409 
  3410 * Isar: proper interfaces for simplification procedures.  Command
  3411 'simproc_setup' declares named simprocs (with match patterns, and body
  3412 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3413 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3414 
  3415 * Isar: an extra pair of brackets around attribute declarations
  3416 abbreviates a theorem reference involving an internal dummy fact,
  3417 which will be ignored later --- only the effect of the attribute on
  3418 the background context will persist.  This form of in-place
  3419 declarations is particularly useful with commands like 'declare' and
  3420 'using', for example ``have A using [[simproc a]] by simp''.
  3421 
  3422 * Isar: method "assumption" (and implicit closing of subproofs) now
  3423 takes simple non-atomic goal assumptions into account: after applying
  3424 an assumption as a rule the resulting subgoals are solved by atomic
  3425 assumption steps.  This is particularly useful to finish 'obtain'
  3426 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3427 without referring to the original premise "!!x. P x ==> thesis" in the
  3428 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3429 more permissive.
  3430 
  3431 * Isar: implicit use of prems from the Isar proof context is
  3432 considered a legacy feature.  Common applications like ``have A .''
  3433 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3434 referencing facts explicitly here improves readability and
  3435 maintainability of proof texts.
  3436 
  3437 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3438 the obtained context from the course of reasoning!  For example:
  3439 
  3440   assume "EX x y. A x & B y"   -- "any previous fact"
  3441   then guess x and y by clarify
  3442 
  3443 This technique is potentially adventurous, depending on the facts and
  3444 proof tools being involved here.
  3445 
  3446 * Isar: known facts from the proof context may be specified as literal
  3447 propositions, using ASCII back-quote syntax.  This works wherever
  3448 named facts used to be allowed so far, in proof commands, proof
  3449 methods, attributes etc.  Literal facts are retrieved from the context
  3450 according to unification of type and term parameters.  For example,
  3451 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3452 theorems in the current context, then these are valid literal facts:
  3453 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3454 
  3455 There is also a proof method "fact" which does the same composition
  3456 for explicit goal states, e.g. the following proof texts coincide with
  3457 certain special cases of literal facts:
  3458 
  3459   have "A" by fact                 ==  note `A`
  3460   have "A ==> B" by fact           ==  note `A ==> B`
  3461   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3462   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3463 
  3464 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3465 outer syntax.  Thus symbolic identifiers may be used without
  3466 additional white space in declarations like this: ``assume *: A''.
  3467 
  3468 * Isar: 'print_facts' prints all local facts of the current context,
  3469 both named and unnamed ones.
  3470 
  3471 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3472 
  3473   def x == "t" and y == "u"
  3474 
  3475 * Isar: added command 'unfolding', which is structurally similar to
  3476 'using', but affects both the goal state and facts by unfolding given
  3477 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3478 'unfolded' attribute may be replaced by first-class proof text.
  3479 
  3480 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3481 and command 'unfolding' now all support object-level equalities
  3482 (potentially conditional).  The underlying notion of rewrite rule is
  3483 analogous to the 'rule_format' attribute, but *not* that of the
  3484 Simplifier (which is usually more generous).
  3485 
  3486 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3487 premises of a theorem by n. Useful in conjunction with drule.
  3488 
  3489 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3490 method expression within a sandbox consisting of the first N
  3491 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3492 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3493 simplifies all new goals that emerge from applying rule foo to the
  3494 originally first one.
  3495 
  3496 * Isar: schematic goals are no longer restricted to higher-order
  3497 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3498 expected.
  3499 
  3500 * Isar: the conclusion of a long theorem statement is now either
  3501 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3502 (essentially a disjunction of cases with local parameters and
  3503 assumptions).  The latter allows to express general elimination rules
  3504 adequately; in this notation common elimination rules look like this:
  3505 
  3506   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3507     assumes "EX x. P x"
  3508     obtains x where "P x"
  3509 
  3510   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3511     assumes "A & B"
  3512     obtains A and B
  3513 
  3514   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3515     assumes "A | B"
  3516     obtains
  3517       A
  3518     | B
  3519 
  3520 The subsequent classical rules even refer to the formal "thesis"
  3521 explicitly:
  3522 
  3523   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3524     obtains "~ thesis"
  3525 
  3526   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3527     obtains "thesis ==> something"
  3528 
  3529 The actual proof of an 'obtains' statement is analogous to that of the
  3530 Isar proof element 'obtain', only that there may be several cases.
  3531 Optional case names may be specified in parentheses; these will be
  3532 available both in the present proof and as annotations in the
  3533 resulting rule, for later use with the 'cases' method (cf. attribute
  3534 case_names).
  3535 
  3536 * Isar: the assumptions of a long theorem statement are available as
  3537 "assms" fact in the proof context.  This is more appropriate than the
  3538 (historical) "prems", which refers to all assumptions of the current
  3539 context, including those from the target locale, proof body etc.
  3540 
  3541 * Isar: 'print_statement' prints theorems from the current theory or
  3542 proof context in long statement form, according to the syntax of a
  3543 top-level lemma.
  3544 
  3545 * Isar: 'obtain' takes an optional case name for the local context
  3546 introduction rule (default "that").
  3547 
  3548 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3549 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3550 to occur.
  3551 
  3552 * Pure: syntax "CONST name" produces a fully internalized constant
  3553 according to the current context.  This is particularly useful for
  3554 syntax translations that should refer to internal constant
  3555 representations independently of name spaces.
  3556 
  3557 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3558 instead of "FOO ". This allows multiple binder declarations to coexist
  3559 in the same context.  INCOMPATIBILITY.
  3560 
  3561 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3562 primitive that also works in a locale context (both for constants and
  3563 fixed variables). Type declaration and internal syntactic representation
  3564 of given constants retrieved from the context. Likewise, the
  3565 'no_notation' command allows to remove given syntax annotations from the
  3566 current context.
  3567 
  3568 * Isar/locales: new derived specification elements 'axiomatization',
  3569 'definition', 'abbreviation', which support type-inference, admit
  3570 object-level specifications (equality, equivalence).  See also the
  3571 isar-ref manual.  Examples:
  3572 
  3573   axiomatization
  3574     eq  (infix "===" 50) where
  3575     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3576 
  3577   definition "f x y = x + y + 1"
  3578   definition g where "g x = f x x"
  3579 
  3580   abbreviation
  3581     neq  (infix "=!=" 50) where
  3582     "x =!= y == ~ (x === y)"
  3583 
  3584 These specifications may be also used in a locale context.  Then the
  3585 constants being introduced depend on certain fixed parameters, and the
  3586 constant name is qualified by the locale base name.  An internal
  3587 abbreviation takes care for convenient input and output, making the
  3588 parameters implicit and using the original short name.  See also
  3589 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3590 entities from a monomorphic theory.
  3591 
  3592 Presently, abbreviations are only available 'in' a target locale, but
  3593 not inherited by general import expressions.  Also note that
  3594 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3595 'translations' in common applications.  The "no_abbrevs" print mode
  3596 prevents folding of abbreviations in term output.
  3597 
  3598 Concrete syntax is attached to specified constants in internal form,
  3599 independently of name spaces.  The parse tree representation is
  3600 slightly different -- use 'notation' instead of raw 'syntax', and
  3601 'translations' with explicit "CONST" markup to accommodate this.
  3602 
  3603 * Pure/Isar: unified syntax for new-style specification mechanisms
  3604 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3605 full type inference and dummy patterns ("_").  For example:
  3606 
  3607   definition "K x _ = x"
  3608 
  3609   inductive conj for A B
  3610   where "A ==> B ==> conj A B"
  3611 
  3612 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3613 the current context.  Print mode "no_abbrevs" prevents inversion of
  3614 abbreviations on output.
  3615 
  3616 * Isar/locales: improved parameter handling: use of locales "var" and
  3617 "struct" no longer necessary; - parameter renamings are no longer
  3618 required to be injective.  For example, this allows to define
  3619 endomorphisms as locale endom = homom mult mult h.
  3620 
  3621 * Isar/locales: changed the way locales with predicates are defined.
  3622 Instead of accumulating the specification, the imported expression is
  3623 now an interpretation.  INCOMPATIBILITY: different normal form of
  3624 locale expressions.  In particular, in interpretations of locales with
  3625 predicates, goals repesenting already interpreted fragments are not
  3626 removed automatically.  Use methods `intro_locales' and
  3627 `unfold_locales'; see below.
  3628 
  3629 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3630 provide backward reasoning on locales predicates.  The methods are
  3631 aware of interpretations and discharge corresponding goals.
  3632 `intro_locales' is less aggressive then `unfold_locales' and does not
  3633 unfold predicates to assumptions.
  3634 
  3635 * Isar/locales: the order in which locale fragments are accumulated
  3636 has changed.  This enables to override declarations from fragments due
  3637 to interpretations -- for example, unwanted simp rules.
  3638 
  3639 * Isar/locales: interpretation in theories and proof contexts has been
  3640 extended.  One may now specify (and prove) equations, which are
  3641 unfolded in interpreted theorems.  This is useful for replacing
  3642 defined concepts (constants depending on locale parameters) by
  3643 concepts already existing in the target context.  Example:
  3644 
  3645   interpretation partial_order ["op <= :: [int, int] => bool"]
  3646     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3647 
  3648 Typically, the constant `partial_order.less' is created by a
  3649 definition specification element in the context of locale
  3650 partial_order.
  3651 
  3652 * Method "induct": improved internal context management to support
  3653 local fixes and defines on-the-fly. Thus explicit meta-level
  3654 connectives !!  and ==> are rarely required anymore in inductive goals
  3655 (using object-logic connectives for this purpose has been long
  3656 obsolete anyway). Common proof patterns are explained in
  3657 src/HOL/Induct/Common_Patterns.thy, see also
  3658 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3659 examples.
  3660 
  3661 * Method "induct": improved handling of simultaneous goals. Instead of
  3662 introducing object-level conjunction, the statement is now split into
  3663 several conclusions, while the corresponding symbolic cases are nested
  3664 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3665 see src/HOL/Induct/Common_Patterns.thy, for example.
  3666 
  3667 * Method "induct": mutual induction rules are now specified as a list
  3668 of rule sharing the same induction cases. HOL packages usually provide
  3669 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3670 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3671 mutual induction rules differently, i.e. like this:
  3672 
  3673   (induct rule: foo_bar.inducts)
  3674   (induct set: foo bar)
  3675   (induct pred: foo bar)
  3676   (induct type: foo bar)
  3677 
  3678 The ML function ProjectRule.projections turns old-style rules into the
  3679 new format.
  3680 
  3681 * Method "coinduct": dual of induction, see
  3682 src/HOL/Library/Coinductive_List.thy for various examples.
  3683 
  3684 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3685 considered a legacy feature.
  3686 
  3687 * Attribute "symmetric" produces result with standardized schematic
  3688 variables (index 0).  Potential INCOMPATIBILITY.
  3689 
  3690 * Simplifier: by default the simplifier trace only shows top level
  3691 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3692 default. Thus there is less danger of being flooded by the trace. The
  3693 trace indicates where parts have been suppressed.
  3694   
  3695 * Provers/classical: removed obsolete classical version of elim_format
  3696 attribute; classical elim/dest rules are now treated uniformly when
  3697 manipulating the claset.
  3698 
  3699 * Provers/classical: stricter checks to ensure that supplied intro,
  3700 dest and elim rules are well-formed; dest and elim rules must have at
  3701 least one premise.
  3702 
  3703 * Provers/classical: attributes dest/elim/intro take an optional
  3704 weight argument for the rule (just as the Pure versions).  Weights are
  3705 ignored by automated tools, but determine the search order of single
  3706 rule steps.
  3707 
  3708 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3709 where the body does not mention the bound variable.  Note that dummy
  3710 patterns implicitly depend on their context of bounds, which makes
  3711 "{_. _}" match any set comprehension as expected.  Potential
  3712 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3713 constant "_idtdummy" in the binding position.
  3714 
  3715 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3716 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3717 for example "A -> B" => "Pi A (%_. B)".
  3718 
  3719 * Pure: 'class_deps' command visualizes the subclass relation, using
  3720 the graph browser tool.
  3721 
  3722 * Pure: 'print_theory' now suppresses certain internal declarations by
  3723 default; use '!' option for full details.
  3724 
  3725 
  3726 *** HOL ***
  3727 
  3728 * Method "metis" proves goals by applying the Metis general-purpose
  3729 resolution prover (see also http://gilith.com/software/metis/).
  3730 Examples are in the directory MetisExamples.  WARNING: the
  3731 Isabelle/HOL-Metis integration does not yet work properly with
  3732 multi-threading.
  3733   
  3734 * Command 'sledgehammer' invokes external automatic theorem provers as
  3735 background processes.  It generates calls to the "metis" method if
  3736 successful. These can be pasted into the proof.  Users do not have to
  3737 wait for the automatic provers to return.  WARNING: does not really
  3738 work with multi-threading.
  3739 
  3740 * New "auto_quickcheck" feature tests outermost goal statements for
  3741 potential counter-examples.  Controlled by ML references
  3742 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3743 5000 milliseconds).  Fails silently if statements is outside of
  3744 executable fragment, or any other codgenerator problem occurs.
  3745 
  3746 * New constant "undefined" with axiom "undefined x = undefined".
  3747 
  3748 * Added class "HOL.eq", allowing for code generation with polymorphic
  3749 equality.
  3750 
  3751 * Some renaming of class constants due to canonical name prefixing in
  3752 the new 'class' package:
  3753 
  3754     HOL.abs ~> HOL.abs_class.abs
  3755     HOL.divide ~> HOL.divide_class.divide
  3756     0 ~> HOL.zero_class.zero
  3757     1 ~> HOL.one_class.one
  3758     op + ~> HOL.plus_class.plus
  3759     op - ~> HOL.minus_class.minus
  3760     uminus ~> HOL.minus_class.uminus
  3761     op * ~> HOL.times_class.times
  3762     op < ~> HOL.ord_class.less
  3763     op <= > HOL.ord_class.less_eq
  3764     Nat.power ~> Power.power_class.power
  3765     Nat.size ~> Nat.size_class.size
  3766     Numeral.number_of ~> Numeral.number_class.number_of
  3767     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3768     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3769     Orderings.min ~> Orderings.ord_class.min
  3770     Orderings.max ~> Orderings.ord_class.max
  3771     Divides.op div ~> Divides.div_class.div
  3772     Divides.op mod ~> Divides.div_class.mod
  3773     Divides.op dvd ~> Divides.div_class.dvd
  3774 
  3775 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3776 
  3777 a) User-defined constants using any of the names "plus", "minus",
  3778 "times", "less" or "less_eq". The standard syntax translations for
  3779 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3780 names.
  3781 
  3782 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3783 INCOMPATIBILITY: use more specific names.
  3784 
  3785 c) Permutative equations (e.g. "a + b = b + a")
  3786 Since the change of names also changes the order of terms, permutative
  3787 rewrite rules may get applied in a different order. Experience shows
  3788 that this is rarely the case (only two adaptions in the whole Isabelle
  3789 distribution).  INCOMPATIBILITY: rewrite proofs
  3790 
  3791 d) ML code directly refering to constant names
  3792 This in general only affects hand-written proof tactics, simprocs and
  3793 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3794 Consider using @{const_name} antiquotation.
  3795 
  3796 * New class "default" with associated constant "default".
  3797 
  3798 * Function "sgn" is now overloaded and available on int, real, complex
  3799 (and other numeric types), using class "sgn".  Two possible defs of
  3800 sgn are given as equational assumptions in the classes sgn_if and
  3801 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3802 INCOMPATIBILITY.
  3803 
  3804 * Locale "partial_order" now unified with class "order" (cf. theory
  3805 Orderings), added parameter "less".  INCOMPATIBILITY.
  3806 
  3807 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3808 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3809 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3810 
  3811 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3812 changed order of proof goals in instance proofs.
  3813 
  3814 * The transitivity reasoner for partial and linear orders is set up
  3815 for classes "order" and "linorder".  Instances of the reasoner are available
  3816 in all contexts importing or interpreting the corresponding locales.
  3817 Method "order" invokes the reasoner separately; the reasoner
  3818 is also integrated with the Simplifier as a solver.  Diagnostic
  3819 command 'print_orders' shows the available instances of the reasoner
  3820 in the current context.
  3821 
  3822 * Localized monotonicity predicate in theory "Orderings"; integrated
  3823 lemmas max_of_mono and min_of_mono with this predicate.
  3824 INCOMPATIBILITY.
  3825 
  3826 * Formulation of theorem "dense" changed slightly due to integration
  3827 with new class dense_linear_order.
  3828 
  3829 * Uniform lattice theory development in HOL.
  3830 
  3831     constants "meet" and "join" now named "inf" and "sup"
  3832     constant "Meet" now named "Inf"
  3833 
  3834     classes "meet_semilorder" and "join_semilorder" now named
  3835       "lower_semilattice" and "upper_semilattice"
  3836     class "lorder" now named "lattice"
  3837     class "comp_lat" now named "complete_lattice"
  3838 
  3839     Instantiation of lattice classes allows explicit definitions
  3840     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3841 
  3842   INCOMPATIBILITY.  Theorem renames:
  3843 
  3844     meet_left_le            ~> inf_le1
  3845     meet_right_le           ~> inf_le2
  3846     join_left_le            ~> sup_ge1
  3847     join_right_le           ~> sup_ge2
  3848     meet_join_le            ~> inf_sup_ord
  3849     le_meetI                ~> le_infI
  3850     join_leI                ~> le_supI
  3851     le_meet                 ~> le_inf_iff
  3852     le_join                 ~> ge_sup_conv
  3853     meet_idempotent         ~> inf_idem
  3854     join_idempotent         ~> sup_idem
  3855     meet_comm               ~> inf_commute
  3856     join_comm               ~> sup_commute
  3857     meet_leI1               ~> le_infI1
  3858     meet_leI2               ~> le_infI2
  3859     le_joinI1               ~> le_supI1
  3860     le_joinI2               ~> le_supI2
  3861     meet_assoc              ~> inf_assoc
  3862     join_assoc              ~> sup_assoc
  3863     meet_left_comm          ~> inf_left_commute
  3864     meet_left_idempotent    ~> inf_left_idem
  3865     join_left_comm          ~> sup_left_commute
  3866     join_left_idempotent    ~> sup_left_idem
  3867     meet_aci                ~> inf_aci
  3868     join_aci                ~> sup_aci
  3869     le_def_meet             ~> le_iff_inf
  3870     le_def_join             ~> le_iff_sup
  3871     join_absorp2            ~> sup_absorb2
  3872     join_absorp1            ~> sup_absorb1
  3873     meet_absorp1            ~> inf_absorb1
  3874     meet_absorp2            ~> inf_absorb2
  3875     meet_join_absorp        ~> inf_sup_absorb
  3876     join_meet_absorp        ~> sup_inf_absorb
  3877     distrib_join_le         ~> distrib_sup_le
  3878     distrib_meet_le         ~> distrib_inf_le
  3879 
  3880     add_meet_distrib_left   ~> add_inf_distrib_left
  3881     add_join_distrib_left   ~> add_sup_distrib_left
  3882     is_join_neg_meet        ~> is_join_neg_inf
  3883     is_meet_neg_join        ~> is_meet_neg_sup
  3884     add_meet_distrib_right  ~> add_inf_distrib_right
  3885     add_join_distrib_right  ~> add_sup_distrib_right
  3886     add_meet_join_distribs  ~> add_sup_inf_distribs
  3887     join_eq_neg_meet        ~> sup_eq_neg_inf
  3888     meet_eq_neg_join        ~> inf_eq_neg_sup
  3889     add_eq_meet_join        ~> add_eq_inf_sup
  3890     meet_0_imp_0            ~> inf_0_imp_0
  3891     join_0_imp_0            ~> sup_0_imp_0
  3892     meet_0_eq_0             ~> inf_0_eq_0
  3893     join_0_eq_0             ~> sup_0_eq_0
  3894     neg_meet_eq_join        ~> neg_inf_eq_sup
  3895     neg_join_eq_meet        ~> neg_sup_eq_inf
  3896     join_eq_if              ~> sup_eq_if
  3897 
  3898     mono_meet               ~> mono_inf
  3899     mono_join               ~> mono_sup
  3900     meet_bool_eq            ~> inf_bool_eq
  3901     join_bool_eq            ~> sup_bool_eq
  3902     meet_fun_eq             ~> inf_fun_eq
  3903     join_fun_eq             ~> sup_fun_eq
  3904     meet_set_eq             ~> inf_set_eq
  3905     join_set_eq             ~> sup_set_eq
  3906     meet1_iff               ~> inf1_iff
  3907     meet2_iff               ~> inf2_iff
  3908     meet1I                  ~> inf1I
  3909     meet2I                  ~> inf2I
  3910     meet1D1                 ~> inf1D1
  3911     meet2D1                 ~> inf2D1
  3912     meet1D2                 ~> inf1D2
  3913     meet2D2                 ~> inf2D2
  3914     meet1E                  ~> inf1E
  3915     meet2E                  ~> inf2E
  3916     join1_iff               ~> sup1_iff
  3917     join2_iff               ~> sup2_iff
  3918     join1I1                 ~> sup1I1
  3919     join2I1                 ~> sup2I1
  3920     join1I1                 ~> sup1I1
  3921     join2I2                 ~> sup1I2
  3922     join1CI                 ~> sup1CI
  3923     join2CI                 ~> sup2CI
  3924     join1E                  ~> sup1E
  3925     join2E                  ~> sup2E
  3926 
  3927     is_meet_Meet            ~> is_meet_Inf
  3928     Meet_bool_def           ~> Inf_bool_def
  3929     Meet_fun_def            ~> Inf_fun_def
  3930     Meet_greatest           ~> Inf_greatest
  3931     Meet_lower              ~> Inf_lower
  3932     Meet_set_def            ~> Inf_set_def
  3933 
  3934     Sup_def                 ~> Sup_Inf
  3935     Sup_bool_eq             ~> Sup_bool_def
  3936     Sup_fun_eq              ~> Sup_fun_def
  3937     Sup_set_eq              ~> Sup_set_def
  3938 
  3939     listsp_meetI            ~> listsp_infI
  3940     listsp_meet_eq          ~> listsp_inf_eq
  3941 
  3942     meet_min                ~> inf_min
  3943     join_max                ~> sup_max
  3944 
  3945 * Added syntactic class "size"; overloaded constant "size" now has
  3946 type "'a::size ==> bool"
  3947 
  3948 * Internal reorganisation of `size' of datatypes: size theorems
  3949 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3950 simplification rules by default!); theorems "prod.size" now named
  3951 "*.size".
  3952 
  3953 * Class "div" now inherits from class "times" rather than "type".
  3954 INCOMPATIBILITY.
  3955 
  3956 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  3957 Linorder etc.  have disappeared; operations defined in terms of
  3958 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  3959 
  3960 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  3961 
  3962 * HOL-Word: New extensive library and type for generic, fixed size
  3963 machine words, with arithemtic, bit-wise, shifting and rotating
  3964 operations, reflection into int, nat, and bool lists, automation for
  3965 linear arithmetic (by automatic reflection into nat or int), including
  3966 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  3967 arithmetic type classes, supporting automatic simplification of
  3968 numerals on all operations.
  3969 
  3970 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  3971 
  3972 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  3973 
  3974 * Code generator library theories:
  3975   - Code_Integer represents HOL integers by big integer literals in target
  3976     languages.
  3977   - Code_Char represents HOL characters by character literals in target
  3978     languages.
  3979   - Code_Char_chr like Code_Char, but also offers treatment of character
  3980     codes; includes Code_Integer.
  3981   - Executable_Set allows to generate code for finite sets using lists.
  3982   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  3983     denominator).
  3984   - Executable_Real implements a subset of real numbers, namly those
  3985     representable by rational numbers.
  3986   - Efficient_Nat implements natural numbers by integers, which in general will
  3987     result in higher efficency; pattern matching with 0/Suc is eliminated;
  3988     includes Code_Integer.
  3989   - Code_Index provides an additional datatype index which is mapped to
  3990     target-language built-in integers.
  3991   - Code_Message provides an additional datatype message_string which is isomorphic to
  3992     strings; messages are mapped to target-language strings.
  3993 
  3994 * New package for inductive predicates
  3995 
  3996   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  3997 
  3998     inductive
  3999       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4000       for z_1 :: U_1 and ... and z_n :: U_m
  4001     where
  4002       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4003     | ...
  4004 
  4005   with full support for type-inference, rather than
  4006 
  4007     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4008 
  4009     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4010     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4011 
  4012     inductive "s z_1 ... z_m"
  4013     intros
  4014       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4015       ...
  4016 
  4017   For backward compatibility, there is a wrapper allowing inductive
  4018   sets to be defined with the new package via
  4019 
  4020     inductive_set
  4021       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4022       for z_1 :: U_1 and ... and z_n :: U_m
  4023     where
  4024       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4025     | ...
  4026 
  4027   or
  4028 
  4029     inductive_set
  4030       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4031       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4032       for z_1 :: U_1 and ... and z_n :: U_m
  4033     where
  4034       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4035     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4036     | ...
  4037 
  4038   if the additional syntax "p ..." is required.
  4039 
  4040   Numerous examples can be found in the subdirectories src/HOL/Auth,
  4041   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  4042 
  4043   INCOMPATIBILITIES:
  4044 
  4045   - Since declaration and definition of inductive sets or predicates
  4046     is no longer separated, abbreviations involving the newly
  4047     introduced sets or predicates must be specified together with the
  4048     introduction rules after the 'where' keyword (see above), rather
  4049     than before the actual inductive definition.
  4050 
  4051   - The variables in induction and elimination rules are now
  4052     quantified in the order of their occurrence in the introduction
  4053     rules, rather than in alphabetical order. Since this may break
  4054     some proofs, these proofs either have to be repaired, e.g. by
  4055     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  4056     statements of the form
  4057 
  4058       case (rule_i a_i_1 ... a_i_{k_i})
  4059 
  4060     or the old order of quantification has to be restored by explicitly adding
  4061     meta-level quantifiers in the introduction rules, i.e.
  4062 
  4063       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  4064 
  4065   - The format of the elimination rules is now
  4066 
  4067       p z_1 ... z_m x_1 ... x_n ==>
  4068         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4069         ==> ... ==> P
  4070 
  4071     for predicates and
  4072 
  4073       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4074         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4075         ==> ... ==> P
  4076 
  4077     for sets rather than
  4078 
  4079       x : s z_1 ... z_m ==>
  4080         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4081         ==> ... ==> P
  4082 
  4083     This may require terms in goals to be expanded to n-tuples
  4084     (e.g. using case_tac or simplification with the split_paired_all
  4085     rule) before the above elimination rule is applicable.
  4086 
  4087   - The elimination or case analysis rules for (mutually) inductive
  4088     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4089     list of rules "p_1_..._p_k.elims" is no longer available.
  4090 
  4091 * New package "function"/"fun" for general recursive functions,
  4092 supporting mutual and nested recursion, definitions in local contexts,
  4093 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4094 for small examples, and the separate tutorial on the function
  4095 package. The old recdef "package" is still available as before, but
  4096 users are encouraged to use the new package.
  4097 
  4098 * Method "lexicographic_order" automatically synthesizes termination
  4099 relations as lexicographic combinations of size measures. 
  4100 
  4101 * Case-expressions allow arbitrary constructor-patterns (including
  4102 "_") and take their order into account, like in functional
  4103 programming.  Internally, this is translated into nested
  4104 case-expressions; missing cases are added and mapped to the predefined
  4105 constant "undefined". In complicated cases printing may no longer show
  4106 the original input but the internal form. Lambda-abstractions allow
  4107 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4108 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4109 variable.
  4110 
  4111 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4112 is an abbreviation for "of_nat :: nat => int". The simplification
  4113 rules for "of_nat" have been changed to work like "int" did
  4114 previously.  Potential INCOMPATIBILITY:
  4115   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4116   - of_nat_diff and of_nat_mult are no longer default simp rules
  4117 
  4118 * Method "algebra" solves polynomial equations over (semi)rings using
  4119 Groebner bases. The (semi)ring structure is defined by locales and the
  4120 tool setup depends on that generic context. Installing the method for
  4121 a specific type involves instantiating the locale and possibly adding
  4122 declarations for computation on the coefficients.  The method is
  4123 already instantiated for natural numbers and for the axiomatic class
  4124 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4125 CALCULEMUS 2007 for the general principles underlying this
  4126 architecture of context-aware proof-tools.
  4127 
  4128 * Method "ferrack" implements quantifier elimination over
  4129 special-purpose dense linear orders using locales (analogous to
  4130 "algebra"). The method is already installed for class
  4131 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4132 rat, etc.
  4133 
  4134 * Former constant "List.op @" now named "List.append".  Use ML
  4135 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4136 circumvent possible incompatibilities when working on ML level.
  4137 
  4138 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4139 
  4140 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4141 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4142 
  4143 * New syntax for Haskell-like list comprehension (input only), eg.
  4144 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4145 
  4146 * The special syntax for function "filter" has changed from [x :
  4147 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4148 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4149 
  4150 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4151 defined on nat only, as an abbreviation for [a..<Suc b]
  4152 INCOMPATIBILITY.
  4153 
  4154 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4155 
  4156 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4157 
  4158 * New lemma collection field_simps (an extension of ring_simps) for
  4159 manipulating (in)equations involving division. Multiplies with all
  4160 denominators that can be proved to be non-zero (in equations) or
  4161 positive/negative (in inequations).
  4162 
  4163 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4164 have been improved and renamed to ring_simps, group_simps and
  4165 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4166 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4167 
  4168 * Theory Library/Commutative_Ring: switched from recdef to function
  4169 package; constants add, mul, pow now curried.  Infix syntax for
  4170 algebraic operations.
  4171 
  4172 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4173 INCOMPATIBILITY.
  4174 
  4175 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4176 INCOMPATIBILITY.
  4177 
  4178 * HOL/records: generalised field-update to take a function on the
  4179 field rather than the new value: r(|A := x|) is translated to A_update
  4180 (K x) r The K-combinator that is internally used is called K_record.
  4181 INCOMPATIBILITY: Usage of the plain update functions has to be
  4182 adapted.
  4183  
  4184 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4185 * x = 0, which are required for a semiring.  Richer structures do not
  4186 inherit from semiring_0 anymore, because this property is a theorem
  4187 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4188 there is more to prove, but this is mostly trivial.
  4189 
  4190 * Class "recpower" is generalized to arbitrary monoids, not just
  4191 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4192 commutativity or semiring properties additionally.
  4193 
  4194 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4195 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4196 better use 'abbreviation'.
  4197 
  4198 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4199 
  4200 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4201 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4202 significant changes for setting up numeral syntax for types:
  4203   - New constants Numeral.pred and Numeral.succ instead
  4204       of former Numeral.bin_pred and Numeral.bin_succ.
  4205   - Use integer operations instead of bin_add, bin_mult and so on.
  4206   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4207   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4208 
  4209 See src/HOL/Integ/IntArith.thy for an example setup.
  4210 
  4211 * Command 'normal_form' computes the normal form of a term that may
  4212 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4213 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4214 heavy-duty computations because the functions are compiled to ML
  4215 first.  Correspondingly, a method "normalization" is provided.  See
  4216 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4217 
  4218 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4219 25 like -->); output depends on the "iff" print_mode, the default is
  4220 "A = B" (with priority 50).
  4221 
  4222 * Relations less (<) and less_eq (<=) are also available on type bool.
  4223 Modified syntax to disallow nesting without explicit parentheses,
  4224 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4225 INCOMPATIBILITY.
  4226 
  4227 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4228 
  4229 * Relation composition operator "op O" now has precedence 75 and binds
  4230 stronger than union and intersection. INCOMPATIBILITY.
  4231 
  4232 * The old set interval syntax "{m..n(}" (and relatives) has been
  4233 removed.  Use "{m..<n}" (and relatives) instead.
  4234 
  4235 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4236 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4237 ``declare [[simproc del: neq]]''.
  4238 
  4239 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4240 True/False.
  4241 
  4242 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4243 
  4244 * Theorem setsum_mult renamed to setsum_right_distrib.
  4245 
  4246 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4247 ``rule'' method.
  4248 
  4249 * Reimplemented methods "sat" and "satx", with several improvements:
  4250 goals no longer need to be stated as "<prems> ==> False", equivalences
  4251 (i.e. "=" on type bool) are handled, variable names of the form
  4252 "lit_<n>" are no longer reserved, significant speedup.
  4253 
  4254 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4255 zChaff is still supported as well.
  4256 
  4257 * 'inductive' and 'datatype': provide projections of mutual rules,
  4258 bundled as foo_bar.inducts;
  4259 
  4260 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4261 Library.
  4262 
  4263 * Library: moved theory Accessible_Part to main HOL.
  4264 
  4265 * Library: added theory Coinductive_List of potentially infinite lists
  4266 as greatest fixed-point.
  4267 
  4268 * Library: added theory AssocList which implements (finite) maps as
  4269 association lists.
  4270 
  4271 * Method "evaluation" solves goals (i.e. a boolean expression)
  4272 efficiently by compiling it to ML.  The goal is "proved" (via an
  4273 oracle) if it evaluates to True.
  4274 
  4275 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4276 also when invoked by the simplifier.  This results in the Simplifier
  4277 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4278 Configuration option fast_arith_split_limit=0 recovers the old
  4279 behavior.
  4280 
  4281 * Support for hex (0x20) and binary (0b1001) numerals.
  4282 
  4283 * New method: reify eqs (t), where eqs are equations for an
  4284 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4285 parameter, computes a term s::'b and a list xs::'a list and proves the
  4286 theorem I xs s = t. This is also known as reification or quoting. The
  4287 resulting theorem is applied to the subgoal to substitute t with I xs
  4288 s.  If t is omitted, the subgoal itself is reified.
  4289 
  4290 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4291 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4292 where f is supposed to be a computable function (in the sense of code
  4293 generattion). The method uses reify to compute s and xs as above then
  4294 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4295 r and finally gets the theorem t = r, which is again applied to the
  4296 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4297 
  4298 * Reflection: Automatic reification now handels binding, an example is
  4299 available in src/HOL/ex/ReflectionEx.thy
  4300 
  4301 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4302 command 'statespace' that is similar to 'record', but introduces an
  4303 abstract specification based on the locale infrastructure instead of
  4304 HOL types.  This leads to extra flexibility in composing state spaces,
  4305 in particular multiple inheritance and renaming of components.
  4306 
  4307 
  4308 *** HOL-Complex ***
  4309 
  4310 * Hyperreal: Functions root and sqrt are now defined on negative real
  4311 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4312 Nonnegativity side conditions have been removed from many lemmas, so
  4313 that more subgoals may now be solved by simplification; potential
  4314 INCOMPATIBILITY.
  4315 
  4316 * Real: new type classes formalize real normed vector spaces and
  4317 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4318 and norm :: 'a => real.
  4319 
  4320 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4321 reals into other types. The overloaded constant Reals :: 'a set is now
  4322 defined as range of_real; potential INCOMPATIBILITY.
  4323 
  4324 * Real: proper support for ML code generation, including 'quickcheck'.
  4325 Reals are implemented as arbitrary precision rationals.
  4326 
  4327 * Hyperreal: Several constants that previously worked only for the
  4328 reals have been generalized, so they now work over arbitrary vector
  4329 spaces. Type annotations may need to be added in some cases; potential
  4330 INCOMPATIBILITY.
  4331 
  4332   Infinitesimal  :: ('a::real_normed_vector) star set
  4333   HFinite        :: ('a::real_normed_vector) star set
  4334   HInfinite      :: ('a::real_normed_vector) star set
  4335   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4336   monad          :: ('a::real_normed_vector) star => 'a star set
  4337   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4338   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4339   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4340   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4341   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4342   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4343   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4344   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4345   sgn            :: 'a::real_normed_vector => 'a
  4346   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4347 
  4348 * Complex: Some complex-specific constants are now abbreviations for
  4349 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4350 hnorm.  Other constants have been entirely removed in favor of the
  4351 polymorphic versions (INCOMPATIBILITY):
  4352 
  4353   approx        <-- capprox
  4354   HFinite       <-- CFinite
  4355   HInfinite     <-- CInfinite
  4356   Infinitesimal <-- CInfinitesimal
  4357   monad         <-- cmonad
  4358   galaxy        <-- cgalaxy
  4359   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4360   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4361   (ns)deriv     <-- (ns)cderiv
  4362 
  4363 
  4364 *** HOL-Algebra ***
  4365 
  4366 * Formalisation of ideals and the quotient construction over rings.
  4367 
  4368 * Order and lattice theory no longer based on records.
  4369 INCOMPATIBILITY.
  4370 
  4371 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4372 greatest_closed.  INCOMPATIBILITY.
  4373 
  4374 * Method algebra is now set up via an attribute.  For examples see
  4375 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4376 of algebraic structures.
  4377 
  4378 * Renamed theory CRing to Ring.
  4379 
  4380 
  4381 *** HOL-Nominal ***
  4382 
  4383 * Substantial, yet incomplete support for nominal datatypes (binding
  4384 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4385 src/HOL/Nominal/Examples.  Prospective users should consult
  4386 http://isabelle.in.tum.de/nominal/
  4387 
  4388 
  4389 *** ML ***
  4390 
  4391 * ML basics: just one true type int, which coincides with IntInf.int
  4392 (even on SML/NJ).
  4393 
  4394 * ML within Isar: antiquotations allow to embed statically-checked
  4395 formal entities in the source, referring to the context available at
  4396 compile-time.  For example:
  4397 
  4398 ML {* @{sort "{zero,one}"} *}
  4399 ML {* @{typ "'a => 'b"} *}
  4400 ML {* @{term "%x. x"} *}
  4401 ML {* @{prop "x == y"} *}
  4402 ML {* @{ctyp "'a => 'b"} *}
  4403 ML {* @{cterm "%x. x"} *}
  4404 ML {* @{cprop "x == y"} *}
  4405 ML {* @{thm asm_rl} *}
  4406 ML {* @{thms asm_rl} *}
  4407 ML {* @{type_name c} *}
  4408 ML {* @{type_syntax c} *}
  4409 ML {* @{const_name c} *}
  4410 ML {* @{const_syntax c} *}
  4411 ML {* @{context} *}
  4412 ML {* @{theory} *}
  4413 ML {* @{theory Pure} *}
  4414 ML {* @{theory_ref} *}
  4415 ML {* @{theory_ref Pure} *}
  4416 ML {* @{simpset} *}
  4417 ML {* @{claset} *}
  4418 ML {* @{clasimpset} *}
  4419 
  4420 The same works for sources being ``used'' within an Isar context.
  4421 
  4422 * ML in Isar: improved error reporting; extra verbosity with
  4423 ML_Context.trace enabled.
  4424 
  4425 * Pure/General/table.ML: the join operations now works via exceptions
  4426 DUP/SAME instead of type option. This is simpler in simple cases, and
  4427 admits slightly more efficient complex applications.
  4428 
  4429 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4430 use Context.generic instead of just theory.
  4431 
  4432 * Pure: datatype Context.generic joins theory/Proof.context and
  4433 provides some facilities for code that works in either kind of
  4434 context, notably GenericDataFun for uniform theory and proof data.
  4435 
  4436 * Pure: simplified internal attribute type, which is now always
  4437 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4438 local (Proof.context) attributes have been discontinued, while
  4439 minimizing code duplication. Thm.rule_attribute and
  4440 Thm.declaration_attribute build canonical attributes; see also structure
  4441 Context for further operations on Context.generic, notably
  4442 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4443 declarations and definitions.
  4444 
  4445 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4446 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4447 init only required for impure data. INCOMPATIBILITY: empty really need
  4448 to be empty (no dependencies on theory content!)
  4449 
  4450 * Pure/kernel: consts certification ignores sort constraints given in
  4451 signature declarations. (This information is not relevant to the
  4452 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4453 potential INCOMPATIBILITY.
  4454 
  4455 * Pure: axiomatic type classes are now purely definitional, with
  4456 explicit proofs of class axioms and super class relations performed
  4457 internally. See Pure/axclass.ML for the main internal interfaces --
  4458 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4459 AxClass.axiomatize_class/classrel/arity supersede
  4460 Sign.add_classes/classrel/arities.
  4461 
  4462 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4463 global/local versions on theory vs. Proof.context have been
  4464 discontinued; Attrib.syntax and Method.syntax have been adapted
  4465 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4466 attributes, methods, etc.
  4467 
  4468 * Pure: several functions of signature "... -> theory -> theory * ..."
  4469 have been reoriented to "... -> theory -> ... * theory" in order to
  4470 allow natural usage in combination with the ||>, ||>>, |-> and
  4471 fold_map combinators.
  4472 
  4473 * Pure: official theorem names (closed derivations) and additional
  4474 comments (tags) are now strictly separate.  Name hints -- which are
  4475 maintained as tags -- may be attached any time without affecting the
  4476 derivation.
  4477 
  4478 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4479 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4480 achieve the old behaviour.
  4481 
  4482 * Pure: the "Goal" constant is now called "prop", supporting a
  4483 slightly more general idea of ``protecting'' meta-level rule
  4484 statements.
  4485 
  4486 * Pure: Logic.(un)varify only works in a global context, which is now
  4487 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4488 Logic.legacy_(un)varify as temporary workaround.
  4489 
  4490 * Pure: structure Name provides scalable operations for generating
  4491 internal variable names, notably Name.variants etc.  This replaces
  4492 some popular functions from term.ML:
  4493 
  4494   Term.variant		->  Name.variant
  4495   Term.variantlist	->  Name.variant_list
  4496   Term.invent_names	->  Name.invent_list
  4497 
  4498 Note that low-level renaming rarely occurs in new code -- operations
  4499 from structure Variable are used instead (see below).
  4500 
  4501 * Pure: structure Variable provides fundamental operations for proper
  4502 treatment of fixed/schematic variables in a context.  For example,
  4503 Variable.import introduces fixes for schematics of given facts and
  4504 Variable.export reverses the effect (up to renaming) -- this replaces
  4505 various freeze_thaw operations.
  4506 
  4507 * Pure: structure Goal provides simple interfaces for
  4508 init/conclude/finish and tactical prove operations (replacing former
  4509 Tactic.prove).  Goal.prove is the canonical way to prove results
  4510 within a given context; Goal.prove_global is a degraded version for
  4511 theory level goals, including a global Drule.standard.  Note that
  4512 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4513 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4514 in a locale context).
  4515 
  4516 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4517 and type checking (Syntax.check_term etc.), with common combinations
  4518 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4519 which are considered legacy and await removal.
  4520 
  4521 * Pure/Syntax: generic interfaces for type unchecking
  4522 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4523 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4524 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4525 available for convenience, but refer to the very same operations using
  4526 a mere theory instead of a full context.
  4527 
  4528 * Isar: simplified treatment of user-level errors, using exception
  4529 ERROR of string uniformly.  Function error now merely raises ERROR,
  4530 without any side effect on output channels.  The Isar toplevel takes
  4531 care of proper display of ERROR exceptions.  ML code may use plain
  4532 handle/can/try; cat_error may be used to concatenate errors like this:
  4533 
  4534   ... handle ERROR msg => cat_error msg "..."
  4535 
  4536 Toplevel ML code (run directly or through the Isar toplevel) may be
  4537 embedded into the Isar toplevel with exception display/debug like
  4538 this:
  4539 
  4540   Isar.toplevel (fn () => ...)
  4541 
  4542 INCOMPATIBILITY, removed special transform_error facilities, removed
  4543 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4544 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4545 -- use plain ERROR instead.
  4546 
  4547 * Isar: theory setup now has type (theory -> theory), instead of a
  4548 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4549 
  4550 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4551 ProofContext.debug/verbose flags.
  4552 
  4553 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4554 theory before entering a proof state.  Transactions now always see a
  4555 quasi-functional intermediate checkpoint, both in interactive and
  4556 batch mode.
  4557 
  4558 * Isar: simplified interfaces for outer syntax.  Renamed
  4559 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4560 OuterSyntax.add_parsers -- this functionality is now included in
  4561 OuterSyntax.command etc.  INCOMPATIBILITY.
  4562 
  4563 * Simplifier: the simpset of a running simplification process now
  4564 contains a proof context (cf. Simplifier.the_context), which is the
  4565 very context that the initial simpset has been retrieved from (by
  4566 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4567 (solver, looper etc.) may depend on arbitrary proof data.
  4568 
  4569 * Simplifier.inherit_context inherits the proof context (plus the
  4570 local bounds) of the current simplification process; any simproc
  4571 etc. that calls the Simplifier recursively should do this!  Removed
  4572 former Simplifier.inherit_bounds, which is already included here --
  4573 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4574 specify an explicit context using Simplifier.context/theory_context.
  4575 
  4576 * Simplifier/Classical Reasoner: more abstract interfaces
  4577 change_simpset/claset for modifying the simpset/claset reference of a
  4578 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4579 INCOMPATIBILITY.
  4580 
  4581 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4582 "Trueprop" etc.
  4583 
  4584 
  4585 *** System ***
  4586 
  4587 * settings: the default heap location within ISABELLE_HOME_USER now
  4588 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4589 Isabelle installations.
  4590 
  4591 * isabelle-process: option -S (secure mode) disables some critical
  4592 operations, notably runtime compilation and evaluation of ML source
  4593 code.
  4594 
  4595 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4596 
  4597 * Support for parallel execution, using native multicore support of
  4598 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4599 independent theories, according to the given theory header
  4600 specifications. The maximum number of worker threads is specified via
  4601 usedir option -M or the "max-threads" setting in Proof General. A
  4602 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4603 to 6 on a 8-core machine.  User-code needs to observe certain
  4604 guidelines for thread-safe programming, see appendix A in the Isar
  4605 Implementation manual.
  4606 
  4607 
  4608 
  4609 New in Isabelle2005 (October 2005)
  4610 ----------------------------------
  4611 
  4612 *** General ***
  4613 
  4614 * Theory headers: the new header syntax for Isar theories is
  4615 
  4616   theory <name>
  4617   imports <theory1> ... <theoryN>
  4618   uses <file1> ... <fileM>
  4619   begin
  4620 
  4621 where the 'uses' part is optional.  The previous syntax
  4622 
  4623   theory <name> = <theory1> + ... + <theoryN>:
  4624 
  4625 will disappear in the next release.  Use isatool fixheaders to convert
  4626 existing theory files.  Note that there is no change in ancient
  4627 non-Isar theories now, but these will disappear soon.
  4628 
  4629 * Theory loader: parent theories can now also be referred to via
  4630 relative and absolute paths.
  4631 
  4632 * Command 'find_theorems' searches for a list of criteria instead of a
  4633 list of constants. Known criteria are: intro, elim, dest, name:string,
  4634 simp:term, and any term. Criteria can be preceded by '-' to select
  4635 theorems that do not match. Intro, elim, dest select theorems that
  4636 match the current goal, name:s selects theorems whose fully qualified
  4637 name contain s, and simp:term selects all simplification rules whose
  4638 lhs match term.  Any other term is interpreted as pattern and selects
  4639 all theorems matching the pattern. Available in ProofGeneral under
  4640 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4641 
  4642   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4643 
  4644 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4645 matching the current goal as introduction rule and not having "HOL."
  4646 in their name (i.e. not being defined in theory HOL).
  4647 
  4648 * Command 'thms_containing' has been discontinued in favour of
  4649 'find_theorems'; INCOMPATIBILITY.
  4650 
  4651 * Communication with Proof General is now 8bit clean, which means that
  4652 Unicode text in UTF-8 encoding may be used within theory texts (both
  4653 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4654 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4655 
  4656   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4657   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4658 
  4659 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4660 Classical Reasoner.  Typical big applications run around 2 times
  4661 faster.
  4662 
  4663 
  4664 *** Document preparation ***
  4665 
  4666 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4667 of raw sources.  Only those symbols that do not require additional
  4668 LaTeX packages (depending on comments in isabellesym.sty) are
  4669 displayed properly, everything else is left verbatim.  isatool display
  4670 and isatool print are used as front ends (these are subject to the
  4671 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4672 
  4673 * Command tags control specific markup of certain regions of text,
  4674 notably folding and hiding.  Predefined tags include "theory" (for
  4675 theory begin and end), "proof" for proof commands, and "ML" for
  4676 commands involving ML code; the additional tags "visible" and
  4677 "invisible" are unused by default.  Users may give explicit tag
  4678 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4679 interpretation of tags is determined by the LaTeX job during document
  4680 preparation: see option -V of isatool usedir, or options -n and -t of
  4681 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4682 \isadroptag.
  4683 
  4684 Several document versions may be produced at the same time via isatool
  4685 usedir (the generated index.html will link all of them).  Typical
  4686 specifications include ''-V document=theory,proof,ML'' to present
  4687 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4688 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4689 these parts without any formal replacement text.  The Isabelle site
  4690 default settings produce ''document'' and ''outline'' versions as
  4691 specified above.
  4692 
  4693 * Several new antiquotations:
  4694 
  4695   @{term_type term} prints a term with its type annotated;
  4696 
  4697   @{typeof term} prints the type of a term;
  4698 
  4699   @{const const} is the same as @{term const}, but checks that the
  4700   argument is a known logical constant;
  4701 
  4702   @{term_style style term} and @{thm_style style thm} print a term or
  4703   theorem applying a "style" to it
  4704 
  4705   @{ML text}
  4706 
  4707 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4708 definitions, equations, inequations etc., 'concl' printing only the
  4709 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4710 to print the specified premise.  TermStyle.add_style provides an ML
  4711 interface for introducing further styles.  See also the "LaTeX Sugar"
  4712 document practical applications.  The ML antiquotation prints
  4713 type-checked ML expressions verbatim.
  4714 
  4715 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4716 and 'text' support optional locale specification '(in loc)', which
  4717 specifies the default context for interpreting antiquotations.  For
  4718 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4719 
  4720 * Option 'locale=NAME' of antiquotations specifies an alternative
  4721 context interpreting the subsequent argument.  For example: @{thm
  4722 [locale=lattice] inf_assoc}.
  4723 
  4724 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4725 a proof context.
  4726 
  4727 * Proper output of antiquotations for theory commands involving a
  4728 proof context (such as 'locale' or 'theorem (in loc) ...').
  4729 
  4730 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4731 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4732 
  4733 * isatool usedir: new option -C (default true) controls whether option
  4734 -D should include a copy of the original document directory; -C false
  4735 prevents unwanted effects such as copying of administrative CVS data.
  4736 
  4737 
  4738 *** Pure ***
  4739 
  4740 * Considerably improved version of 'constdefs' command.  Now performs
  4741 automatic type-inference of declared constants; additional support for
  4742 local structure declarations (cf. locales and HOL records), see also
  4743 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4744 sequential dependencies of definitions within a single 'constdefs'
  4745 section; moreover, the declared name needs to be an identifier.  If
  4746 all fails, consider to fall back on 'consts' and 'defs' separately.
  4747 
  4748 * Improved indexed syntax and implicit structures.  First of all,
  4749 indexed syntax provides a notational device for subscripted
  4750 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4751 expressions.  Secondly, in a local context with structure
  4752 declarations, number indexes \<^sub>n or the empty index (default
  4753 number 1) refer to a certain fixed variable implicitly; option
  4754 show_structs controls printing of implicit structures.  Typical
  4755 applications of these concepts involve record types and locales.
  4756 
  4757 * New command 'no_syntax' removes grammar declarations (and
  4758 translations) resulting from the given syntax specification, which is
  4759 interpreted in the same manner as for the 'syntax' command.
  4760 
  4761 * 'Advanced' translation functions (parse_translation etc.) may depend
  4762 on the signature of the theory context being presently used for
  4763 parsing/printing, see also isar-ref manual.
  4764 
  4765 * Improved 'oracle' command provides a type-safe interface to turn an
  4766 ML expression of type theory -> T -> term into a primitive rule of
  4767 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4768 is already included here); see also FOL/ex/IffExample.thy;
  4769 INCOMPATIBILITY.
  4770 
  4771 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4772 before); "cI" is no longer bound, use "c.intro" instead.
  4773 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4774 axclasses vs. locales.
  4775 
  4776 * Improved internal renaming of symbolic identifiers -- attach primes
  4777 instead of base 26 numbers.
  4778 
  4779 * New flag show_question_marks controls printing of leading question
  4780 marks in schematic variable names.
  4781 
  4782 * In schematic variable names, *any* symbol following \<^isub> or
  4783 \<^isup> is now treated as part of the base name.  For example, the
  4784 following works without printing of awkward ".0" indexes:
  4785 
  4786   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4787     by simp
  4788 
  4789 * Inner syntax includes (*(*nested*) comments*).
  4790 
  4791 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4792 annotations as "(00...)".
  4793 
  4794 * Clear separation of logical types and nonterminals, where the latter
  4795 may only occur in 'syntax' specifications or type abbreviations.
  4796 Before that distinction was only partially implemented via type class
  4797 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4798 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4799 exotic syntax specifications may require further adaption
  4800 (e.g. Cube/Cube.thy).
  4801 
  4802 * Removed obsolete type class "logic", use the top sort {} instead.
  4803 Note that non-logical types should be declared as 'nonterminals'
  4804 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4805 specifications.
  4806 
  4807 * Attributes 'induct' and 'cases': type or set names may now be
  4808 locally fixed variables as well.
  4809 
  4810 * Simplifier: can now control the depth to which conditional rewriting
  4811 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4812 Limit.
  4813 
  4814 * Simplifier: simplification procedures may now take the current
  4815 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4816 interface), which is very useful for calling the Simplifier
  4817 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4818 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4819 low-level mk_simproc no longer applies Logic.varify internally, to
  4820 allow for use in a context of fixed variables.
  4821 
  4822 * thin_tac now works even if the assumption being deleted contains !!
  4823 or ==>.  More generally, erule now works even if the major premise of
  4824 the elimination rule contains !! or ==>.
  4825 
  4826 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4827 
  4828 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4829 from Pure, which contains all common declarations already.  Both
  4830 theories are defined via plain Isabelle/Isar .thy files.
  4831 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4832 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4833 use isatool fixcpure to adapt your theory and ML sources.
  4834 
  4835 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4836 selections of theorems in named facts via index ranges.
  4837 
  4838 * 'print_theorems': in theory mode, really print the difference
  4839 wrt. the last state (works for interactive theory development only),
  4840 in proof mode print all local facts (cf. 'print_facts');
  4841 
  4842 * 'hide': option '(open)' hides only base names.
  4843 
  4844 * More efficient treatment of intermediate checkpoints in interactive
  4845 theory development.
  4846 
  4847 * Code generator is now invoked via code_module (incremental code
  4848 generation) and code_library (modular code generation, ML structures
  4849 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4850 must be quoted when used as identifiers.
  4851 
  4852 * New 'value' command for reading, evaluating and printing terms using
  4853 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4854 quoted when used as identifier.
  4855 
  4856 
  4857 *** Locales ***
  4858 
  4859 * New commands for the interpretation of locale expressions in
  4860 theories (1), locales (2) and proof contexts (3).  These generate
  4861 proof obligations from the expression specification.  After the
  4862 obligations have been discharged, theorems of the expression are added
  4863 to the theory, target locale or proof context.  The synopsis of the
  4864 commands is a follows:
  4865 
  4866   (1) interpretation expr inst
  4867   (2) interpretation target < expr
  4868   (3) interpret expr inst
  4869 
  4870 Interpretation in theories and proof contexts require a parameter
  4871 instantiation of terms from the current context.  This is applied to
  4872 specifications and theorems of the interpreted expression.
  4873 Interpretation in locales only permits parameter renaming through the
  4874 locale expression.  Interpretation is smart in that interpretations
  4875 that are active already do not occur in proof obligations, neither are
  4876 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4877 inspect active interpretations of a particular locale.  For details,
  4878 see the Isar Reference manual.  Examples can be found in
  4879 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4880 
  4881 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4882 'interpret' instead.
  4883 
  4884 * New context element 'constrains' for adding type constraints to
  4885 parameters.
  4886 
  4887 * Context expressions: renaming of parameters with syntax
  4888 redeclaration.
  4889 
  4890 * Locale declaration: 'includes' disallowed.
  4891 
  4892 * Proper static binding of attribute syntax -- i.e. types / terms /
  4893 facts mentioned as arguments are always those of the locale definition
  4894 context, independently of the context of later invocations.  Moreover,
  4895 locale operations (renaming and type / term instantiation) are applied
  4896 to attribute arguments as expected.
  4897 
  4898 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4899 actual attributes; rare situations may require Attrib.attribute to
  4900 embed those attributes into Attrib.src that lack concrete syntax.
  4901 Attribute implementations need to cooperate properly with the static
  4902 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4903 Attrib.XXX_thm etc. already do the right thing without further
  4904 intervention.  Only unusual applications -- such as "where" or "of"
  4905 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4906 on the context and the facts involved -- may have to assign parsed
  4907 values to argument tokens explicitly.
  4908 
  4909 * Changed parameter management in theorem generation for long goal
  4910 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4911 theorem statement in rare situations.
  4912 
  4913 * Locale inspection command 'print_locale' omits notes elements.  Use
  4914 'print_locale!' to have them included in the output.
  4915 
  4916 
  4917 *** Provers ***
  4918 
  4919 * Provers/hypsubst.ML: improved version of the subst method, for
  4920 single-step rewriting: it now works in bound variable contexts. New is
  4921 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4922 rewrite a different subterm than the original subst method, which is
  4923 still available as 'simplesubst'.
  4924 
  4925 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4926 and quasi orders.
  4927 
  4928 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4929 reflexive-transitive closure of relations.
  4930 
  4931 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4932 limit (previously hard-coded with a value of 20) user-definable.
  4933 
  4934 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4935 is peformed already.  Object-logics merely need to finish their
  4936 initial simpset configuration as before.  INCOMPATIBILITY.
  4937 
  4938 
  4939 *** HOL ***
  4940 
  4941 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4942 
  4943   syntax (epsilon)
  4944     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4945 
  4946 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4947 and x-symbol; use option '-m epsilon' to get it actually printed.
  4948 Moreover, the mathematically important symbolic identifier \<epsilon>
  4949 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4950 
  4951 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  4952 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  4953 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  4954 support corresponding Isar calculations.
  4955 
  4956 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  4957 instead of ":".
  4958 
  4959 * theory SetInterval: changed the syntax for open intervals:
  4960 
  4961   Old       New
  4962   {..n(}    {..<n}
  4963   {)n..}    {n<..}
  4964   {m..n(}   {m..<n}
  4965   {)m..n}   {m<..n}
  4966   {)m..n(}  {m<..<n}
  4967 
  4968 The old syntax is still supported but will disappear in the next
  4969 release.  For conversion use the following Emacs search and replace
  4970 patterns (these are not perfect but work quite well):
  4971 
  4972   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  4973   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  4974 
  4975 * Theory Commutative_Ring (in Library): method comm_ring for proving
  4976 equalities in commutative rings; method 'algebra' provides a generic
  4977 interface.
  4978 
  4979 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  4980 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  4981 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  4982 be a tuple pattern.
  4983 
  4984 Some new syntax forms are available:
  4985 
  4986   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  4987   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  4988   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  4989   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  4990 
  4991 The latter form "\<Sum>x < k. e" used to be based on a separate
  4992 function "Summation", which has been discontinued.
  4993 
  4994 * theory Finite_Set: in structured induction proofs, the insert case
  4995 is now 'case (insert x F)' instead of the old counterintuitive 'case
  4996 (insert F x)'.
  4997 
  4998 * The 'refute' command has been extended to support a much larger
  4999 fragment of HOL, including axiomatic type classes, constdefs and
  5000 typedefs, inductive datatypes and recursion.
  5001 
  5002 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  5003 Requires zChaff with proof generation to be installed.  See
  5004 HOL/ex/SAT_Examples.thy for examples.
  5005 
  5006 * Datatype induction via method 'induct' now preserves the name of the
  5007 induction variable. For example, when proving P(xs::'a list) by
  5008 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  5009 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  5010 in unstructured proof scripts.
  5011 
  5012 * Reworked implementation of records.  Improved scalability for
  5013 records with many fields, avoiding performance problems for type
  5014 inference. Records are no longer composed of nested field types, but
  5015 of nested extension types. Therefore the record type only grows linear
  5016 in the number of extensions and not in the number of fields.  The
  5017 top-level (users) view on records is preserved.  Potential
  5018 INCOMPATIBILITY only in strange cases, where the theory depends on the
  5019 old record representation. The type generated for a record is called
  5020 <record_name>_ext_type.
  5021 
  5022 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  5023 proofs triggered by a record definition or a simproc (if
  5024 quick_and_dirty is enabled).  Definitions of large records can take
  5025 quite long.
  5026 
  5027 New simproc record_upd_simproc for simplification of multiple record
  5028 updates enabled by default.  Moreover, trivial updates are also
  5029 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  5030 occasionally, since simplification is more powerful by default.
  5031 
  5032 * typedef: proper support for polymorphic sets, which contain extra
  5033 type-variables in the term.
  5034 
  5035 * Simplifier: automatically reasons about transitivity chains
  5036 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  5037 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  5038 old proofs break occasionally as simplification may now solve more
  5039 goals than previously.
  5040 
  5041 * Simplifier: converts x <= y into x = y if assumption y <= x is
  5042 present.  Works for all partial orders (class "order"), in particular
  5043 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  5044 just like y <= x.
  5045 
  5046 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  5047 bound variable or a constant then the let is unfolded.  Otherwise
  5048 first a is simplified to b, and then f b is simplified to g. If
  5049 possible we abstract b from g arriving at "let x = b in h x",
  5050 otherwise we unfold the let and arrive at g.  The simproc can be
  5051 enabled/disabled by the reference use_let_simproc.  Potential
  5052 INCOMPATIBILITY since simplification is more powerful by default.
  5053 
  5054 * Classical reasoning: the meson method now accepts theorems as arguments.
  5055 
  5056 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  5057 jobs to provide advice on the provability of subgoals.
  5058 
  5059 * Theory OrderedGroup and Ring_and_Field: various additions and
  5060 improvements to faciliate calculations involving equalities and
  5061 inequalities.
  5062 
  5063 The following theorems have been eliminated or modified
  5064 (INCOMPATIBILITY):
  5065 
  5066   abs_eq             now named abs_of_nonneg
  5067   abs_of_ge_0        now named abs_of_nonneg
  5068   abs_minus_eq       now named abs_of_nonpos
  5069   imp_abs_id         now named abs_of_nonneg
  5070   imp_abs_neg_id     now named abs_of_nonpos
  5071   mult_pos           now named mult_pos_pos
  5072   mult_pos_le        now named mult_nonneg_nonneg
  5073   mult_pos_neg_le    now named mult_nonneg_nonpos
  5074   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5075   mult_neg           now named mult_neg_neg
  5076   mult_neg_le        now named mult_nonpos_nonpos
  5077 
  5078 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5079      
  5080      zero_le_square
  5081      not_square_less_zero 
  5082 
  5083   The following lemmas have been deleted from Real/RealPow:
  5084   
  5085      realpow_zero_zero
  5086      realpow_two
  5087      realpow_less
  5088      zero_le_power
  5089      realpow_two_le
  5090      abs_realpow_two
  5091      realpow_two_abs     
  5092 
  5093 * Theory Parity: added rules for simplifying exponents.
  5094 
  5095 * Theory List:
  5096 
  5097 The following theorems have been eliminated or modified
  5098 (INCOMPATIBILITY):
  5099 
  5100   list_all_Nil       now named list_all.simps(1)
  5101   list_all_Cons      now named list_all.simps(2)
  5102   list_all_conv      now named list_all_iff
  5103   set_mem_eq         now named mem_iff
  5104 
  5105 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5106 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5107 
  5108 
  5109 *** HOL-Complex ***
  5110 
  5111 * Theory RealDef: better support for embedding natural numbers and
  5112 integers in the reals.
  5113 
  5114 The following theorems have been eliminated or modified
  5115 (INCOMPATIBILITY):
  5116 
  5117   exp_ge_add_one_self  now requires no hypotheses
  5118   real_of_int_add      reversed direction of equality (use [symmetric])
  5119   real_of_int_minus    reversed direction of equality (use [symmetric])
  5120   real_of_int_diff     reversed direction of equality (use [symmetric])
  5121   real_of_int_mult     reversed direction of equality (use [symmetric])
  5122 
  5123 * Theory RComplete: expanded support for floor and ceiling functions.
  5124 
  5125 * Theory Ln is new, with properties of the natural logarithm
  5126 
  5127 * Hyperreal: There is a new type constructor "star" for making
  5128 nonstandard types.  The old type names are now type synonyms:
  5129 
  5130   hypreal = real star
  5131   hypnat = nat star
  5132   hcomplex = complex star
  5133 
  5134 * Hyperreal: Many groups of similarly-defined constants have been
  5135 replaced by polymorphic versions (INCOMPATIBILITY):
  5136 
  5137   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5138 
  5139   starset      <-- starsetNat, starsetC
  5140   *s*          <-- *sNat*, *sc*
  5141   starset_n    <-- starsetNat_n, starsetC_n
  5142   *sn*         <-- *sNatn*, *scn*
  5143   InternalSets <-- InternalNatSets, InternalCSets
  5144 
  5145   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5146   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5147   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5148   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5149   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5150 
  5151 * Hyperreal: Many type-specific theorems have been removed in favor of
  5152 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5153 
  5154   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5155   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5156   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5157   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5158   right_minus <-- hypreal_add_minus
  5159   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5160   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5161   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5162   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5163   mult_1_right <-- hcomplex_mult_one_right
  5164   mult_zero_left <-- hcomplex_mult_zero_left
  5165   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5166   right_distrib <-- hypnat_add_mult_distrib2
  5167   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5168   right_inverse <-- hypreal_mult_inverse
  5169   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5170   order_refl <-- {hypreal,hypnat}_le_refl
  5171   order_trans <-- {hypreal,hypnat}_le_trans
  5172   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5173   order_less_le <-- {hypreal,hypnat}_less_le
  5174   linorder_linear <-- {hypreal,hypnat}_le_linear
  5175   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5176   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5177   add_nonneg_nonneg <-- hypreal_le_add_order
  5178 
  5179 * Hyperreal: Separate theorems having to do with type-specific
  5180 versions of constants have been merged into theorems that apply to the
  5181 new polymorphic constants (INCOMPATIBILITY):
  5182 
  5183   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5184   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5185   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5186   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5187   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5188   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5189   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5190   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5191   STAR_diff <-- {STAR,STARC}_diff
  5192   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5193     STARC_hcomplex_of_complex}_image_subset
  5194   starset_n_Un <-- starset{Nat,C}_n_Un
  5195   starset_n_Int <-- starset{Nat,C}_n_Int
  5196   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5197   starset_n_diff <-- starset{Nat,C}_n_diff
  5198   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5199   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5200   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5201   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5202   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5203   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5204   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5205   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5206   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5207   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5208   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5209   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5210   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5211   starfun_diff <-- starfun{C,RC,CR}_diff
  5212   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5213   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5214   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5215   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5216   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5217   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5218   starfun_Id <-- starfunC_Id
  5219   starfun_approx <-- starfun{Nat,CR}_approx
  5220   starfun_capprox <-- starfun{C,RC}_capprox
  5221   starfun_abs <-- starfunNat_rabs
  5222   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5223   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5224   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5225   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5226   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5227   starfun_add_approx <-- starfunCR_add_approx
  5228   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5229   starfun_divide <-- starfun{C,CR,RC}_divide
  5230   starfun_n <-- starfun{Nat,C}_n
  5231   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5232   starfun_n_add <-- starfun{Nat,C}_n_add
  5233   starfun_n_add_minus <-- starfunNat_n_add_minus
  5234   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5235   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5236   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5237 
  5238   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5239   star_n_minus <-- {hypreal,hcomplex}_minus
  5240   star_n_diff <-- {hypreal,hcomplex}_diff
  5241   star_n_mult <-- {hypreal,hcomplex}_mult
  5242   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5243   star_n_le <-- {hypreal,hypnat}_le
  5244   star_n_less <-- {hypreal,hypnat}_less
  5245   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5246   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5247   star_n_abs <-- hypreal_hrabs
  5248   star_n_divide <-- hcomplex_divide
  5249 
  5250   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5251   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5252   star_of_diff <-- hypreal_of_real_diff
  5253   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5254   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5255   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5256   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5257   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5258   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5259   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5260   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5261   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5262   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5263   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5264   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5265   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5266   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5267   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5268   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5269   star_of_power <-- hypreal_of_real_power
  5270   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5271 
  5272 * Hyperreal: new method "transfer" that implements the transfer
  5273 principle of nonstandard analysis. With a subgoal that mentions
  5274 nonstandard types like "'a star", the command "apply transfer"
  5275 replaces it with an equivalent one that mentions only standard types.
  5276 To be successful, all free variables must have standard types; non-
  5277 standard variables must have explicit universal quantifiers.
  5278 
  5279 * Hyperreal: A theory of Taylor series.
  5280 
  5281 
  5282 *** HOLCF ***
  5283 
  5284 * Discontinued special version of 'constdefs' (which used to support
  5285 continuous functions) in favor of the general Pure one with full
  5286 type-inference.
  5287 
  5288 * New simplification procedure for solving continuity conditions; it
  5289 is much faster on terms with many nested lambda abstractions (cubic
  5290 instead of exponential time).
  5291 
  5292 * New syntax for domain package: selector names are now optional.
  5293 Parentheses should be omitted unless argument is lazy, for example:
  5294 
  5295   domain 'a stream = cons "'a" (lazy "'a stream")
  5296 
  5297 * New command 'fixrec' for defining recursive functions with pattern
  5298 matching; defining multiple functions with mutual recursion is also
  5299 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5300 sinr, or any data constructor defined by the domain package. The given
  5301 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5302 syntax and examples.
  5303 
  5304 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5305 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5306 but the proof obligation additionally includes an admissibility
  5307 requirement. The packages generate instances of class cpo or pcpo,
  5308 with continuity and strictness theorems for Rep and Abs.
  5309 
  5310 * HOLCF: Many theorems have been renamed according to a more standard naming
  5311 scheme (INCOMPATIBILITY):
  5312 
  5313   foo_inject:  "foo$x = foo$y ==> x = y"
  5314   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5315   foo_less:    "(foo$x << foo$y) = (x << y)"
  5316   foo_strict:  "foo$UU = UU"
  5317   foo_defined: "... ==> foo$x ~= UU"
  5318   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5319 
  5320 
  5321 *** ZF ***
  5322 
  5323 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5324 including the First Isomorphism Theorem (on quotienting by the kernel
  5325 of a homomorphism).
  5326 
  5327 * ZF/Simplifier: install second copy of type solver that actually
  5328 makes use of TC rules declared to Isar proof contexts (or locales);
  5329 the old version is still required for ML proof scripts.
  5330 
  5331 
  5332 *** Cube ***
  5333 
  5334 * Converted to Isar theory format; use locales instead of axiomatic
  5335 theories.
  5336 
  5337 
  5338 *** ML ***
  5339 
  5340 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5341 for ||>, ||>>, |>>,
  5342 
  5343 * Pure/library.ML no longer defines its own option datatype, but uses
  5344 that of the SML basis, which has constructors NONE and SOME instead of
  5345 None and Some, as well as exception Option.Option instead of OPTION.
  5346 The functions the, if_none, is_some, is_none have been adapted
  5347 accordingly, while Option.map replaces apsome.
  5348 
  5349 * Pure/library.ML: the exception LIST has been given up in favour of
  5350 the standard exceptions Empty and Subscript, as well as
  5351 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5352 superceded by the standard hd and tl functions etc.
  5353 
  5354 A number of basic list functions are no longer exported to the ML
  5355 toplevel, as they are variants of predefined functions.  The following
  5356 suggests how one can translate existing code:
  5357 
  5358     rev_append xs ys = List.revAppend (xs, ys)
  5359     nth_elem (i, xs) = List.nth (xs, i)
  5360     last_elem xs = List.last xs
  5361     flat xss = List.concat xss
  5362     seq fs = List.app fs
  5363     partition P xs = List.partition P xs
  5364     mapfilter f xs = List.mapPartial f xs
  5365 
  5366 * Pure/library.ML: several combinators for linear functional
  5367 transformations, notably reverse application and composition:
  5368 
  5369   x |> f                f #> g
  5370   (x, y) |-> f          f #-> g
  5371 
  5372 * Pure/library.ML: introduced/changed precedence of infix operators:
  5373 
  5374   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5375   infix 2 ?;
  5376   infix 3 o oo ooo oooo;
  5377   infix 4 ~~ upto downto;
  5378 
  5379 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5380 infix operators.
  5381 
  5382 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5383 fold_map support linear functional transformations and nesting.  For
  5384 example:
  5385 
  5386   fold f [x1, ..., xN] y =
  5387     y |> f x1 |> ... |> f xN
  5388 
  5389   (fold o fold) f [xs1, ..., xsN] y =
  5390     y |> fold f xs1 |> ... |> fold f xsN
  5391 
  5392   fold f [x1, ..., xN] =
  5393     f x1 #> ... #> f xN
  5394 
  5395   (fold o fold) f [xs1, ..., xsN] =
  5396     fold f xs1 #> ... #> fold f xsN
  5397 
  5398 * Pure/library.ML: the following selectors on type 'a option are
  5399 available:
  5400 
  5401   the:               'a option -> 'a  (*partial*)
  5402   these:             'a option -> 'a  where 'a = 'b list
  5403   the_default: 'a -> 'a option -> 'a
  5404   the_list:          'a option -> 'a list
  5405 
  5406 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5407 basic operations for association lists, following natural argument
  5408 order; moreover the explicit equality predicate passed here avoids
  5409 potentially expensive polymorphic runtime equality checks.
  5410 The old functions may be expressed as follows:
  5411 
  5412   assoc = uncurry (AList.lookup (op =))
  5413   assocs = these oo AList.lookup (op =)
  5414   overwrite = uncurry (AList.update (op =)) o swap
  5415 
  5416 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5417 
  5418   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5419   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5420 
  5421 replacing make_keylist and keyfilter (occassionally used)
  5422 Naive rewrites:
  5423 
  5424   make_keylist = AList.make
  5425   keyfilter = AList.find (op =)
  5426 
  5427 * eq_fst and eq_snd now take explicit equality parameter, thus
  5428   avoiding eqtypes. Naive rewrites:
  5429 
  5430     eq_fst = eq_fst (op =)
  5431     eq_snd = eq_snd (op =)
  5432 
  5433 * Removed deprecated apl and apr (rarely used).
  5434   Naive rewrites:
  5435 
  5436     apl (n, op) =>>= curry op n
  5437     apr (op, m) =>>= fn n => op (n, m)
  5438 
  5439 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5440 provides a reasonably efficient light-weight implementation of sets as
  5441 lists.
  5442 
  5443 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5444 few new operations; existing lookup and update are now curried to
  5445 follow natural argument order (for use with fold etc.);
  5446 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5447 
  5448 * Pure/General: output via the Isabelle channels of
  5449 writeln/warning/error etc. is now passed through Output.output, with a
  5450 hook for arbitrary transformations depending on the print_mode
  5451 (cf. Output.add_mode -- the first active mode that provides a output
  5452 function wins).  Already formatted output may be embedded into further
  5453 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5454 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5455 accommodate easy composition of diagnostic messages etc.  Programmers
  5456 rarely need to care about Output.output or Output.raw at all, with
  5457 some notable exceptions: Output.output is required when bypassing the
  5458 standard channels (writeln etc.), or in token translations to produce
  5459 properly formatted results; Output.raw is required when capturing
  5460 already output material that will eventually be presented to the user
  5461 a second time.  For the default print mode, both Output.output and
  5462 Output.raw have no effect.
  5463 
  5464 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5465 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5466 cumulative results are displayed at the end of a batch session.
  5467 
  5468 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5469 replaced by File.platform_path and File.shell_path (with appropriate
  5470 hooks).  This provides a clean interface for unusual systems where the
  5471 internal and external process view of file names are different.
  5472 
  5473 * Pure: more efficient orders for basic syntactic entities: added
  5474 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5475 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5476 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5477 orders now -- potential INCOMPATIBILITY for code that depends on a
  5478 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5479 Library.sort_strings on result).
  5480 
  5481 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5482 fold_types traverse types/terms from left to right, observing natural
  5483 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5484 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5485 
  5486 * Pure: name spaces have been refined, with significant changes of the
  5487 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5488 to extern(_table).  The plain name entry path is superceded by a
  5489 general 'naming' context, which also includes the 'policy' to produce
  5490 a fully qualified name and external accesses of a fully qualified
  5491 name; NameSpace.extend is superceded by context dependent
  5492 Sign.declare_name.  Several theory and proof context operations modify
  5493 the naming context.  Especially note Theory.restore_naming and
  5494 ProofContext.restore_naming to get back to a sane state; note that
  5495 Theory.add_path is no longer sufficient to recover from
  5496 Theory.absolute_path in particular.
  5497 
  5498 * Pure: new flags short_names (default false) and unique_names
  5499 (default true) for controlling output of qualified names.  If
  5500 short_names is set, names are printed unqualified.  If unique_names is
  5501 reset, the name prefix is reduced to the minimum required to achieve
  5502 the original result when interning again, even if there is an overlap
  5503 with earlier declarations.
  5504 
  5505 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5506 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5507 (useful for printing error messages).  INCOMPATIBILITY.
  5508 
  5509 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5510 Theory.theory are now identified, referring to the universal
  5511 Context.theory (see Pure/context.ML).  Actual signature and theory
  5512 content is managed as theory data.  The old code and interfaces were
  5513 spread over many files and structures; the new arrangement introduces
  5514 considerable INCOMPATIBILITY to gain more clarity:
  5515 
  5516   Context -- theory management operations (name, identity, inclusion,
  5517     parents, ancestors, merge, etc.), plus generic theory data;
  5518 
  5519   Sign -- logical signature and syntax operations (declaring consts,
  5520     types, etc.), plus certify/read for common entities;
  5521 
  5522   Theory -- logical theory operations (stating axioms, definitions,
  5523     oracles), plus a copy of logical signature operations (consts,
  5524     types, etc.); also a few basic management operations (Theory.copy,
  5525     Theory.merge, etc.)
  5526 
  5527 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5528 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5529 for convenience -- they merely return the theory.
  5530 
  5531 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5532 
  5533 * Pure: the Isar proof context type is already defined early in Pure
  5534 as Context.proof (note that ProofContext.context and Proof.context are
  5535 aliases, where the latter is the preferred name).  This enables other
  5536 Isabelle components to refer to that type even before Isar is present.
  5537 
  5538 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5539 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5540 any of these kinds.  For example, Sign.intern typeK is now
  5541 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5542 Theory.hide_types.  Also note that former
  5543 Theory.hide_classes/types/consts are now
  5544 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5545 internalize their arguments!  INCOMPATIBILITY.
  5546 
  5547 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5548 datatype thmref (with constructors Name and NameSelection) instead of
  5549 plain string -- INCOMPATIBILITY;
  5550 
  5551 * Pure: cases produced by proof methods specify options, where NONE
  5552 means to remove case bindings -- INCOMPATIBILITY in
  5553 (RAW_)METHOD_CASES.
  5554 
  5555 * Pure: the following operations retrieve axioms or theorems from a
  5556 theory node or theory hierarchy, respectively:
  5557 
  5558   Theory.axioms_of: theory -> (string * term) list
  5559   Theory.all_axioms_of: theory -> (string * term) list
  5560   PureThy.thms_of: theory -> (string * thm) list
  5561   PureThy.all_thms_of: theory -> (string * thm) list
  5562 
  5563 * Pure: print_tac now outputs the goal through the trace channel.
  5564 
  5565 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5566 Reference Toplevel.debug (default false) controls detailed printing
  5567 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5568 controls execution profiling -- set to 1 for time and 2 for space
  5569 (both increase the runtime).
  5570 
  5571 * Isar session: The initial use of ROOT.ML is now always timed,
  5572 i.e. the log will show the actual process times, in contrast to the
  5573 elapsed wall-clock time that the outer shell wrapper produces.
  5574 
  5575 * Simplifier: improved handling of bound variables (nameless
  5576 representation, avoid allocating new strings).  Simprocs that invoke
  5577 the Simplifier recursively should use Simplifier.inherit_bounds to
  5578 avoid local name clashes.  Failure to do so produces warnings
  5579 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5580 for further details.
  5581 
  5582 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5583 bindings for all theorems stored within a given theory; this may help
  5584 in porting non-Isar theories to Isar ones, while keeping ML proof
  5585 scripts for the time being.
  5586 
  5587 * ML operator HTML.with_charset specifies the charset begin used for
  5588 generated HTML files.  For example:
  5589 
  5590   HTML.with_charset "utf-8" use_thy "Hebrew";
  5591   HTML.with_charset "utf-8" use_thy "Chinese";
  5592 
  5593 
  5594 *** System ***
  5595 
  5596 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5597 isabelle, isatool etc.).
  5598 
  5599 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5600 isatool doc, isatool mkdir, display_drafts etc.).
  5601 
  5602 * isatool usedir: option -f allows specification of the ML file to be
  5603 used by Isabelle; default is ROOT.ML.
  5604 
  5605 * New isatool version outputs the version identifier of the Isabelle
  5606 distribution being used.
  5607 
  5608 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5609 (containing Boolean satisfiability problems) into Isabelle/HOL
  5610 theories.
  5611 
  5612 
  5613 
  5614 New in Isabelle2004 (April 2004)
  5615 --------------------------------
  5616 
  5617 *** General ***
  5618 
  5619 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5620   Replaces linorder.ML.
  5621 
  5622 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5623   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5624   (\<a>...\<z>), are now considered normal letters, and can therefore
  5625   be used anywhere where an ASCII letter (a...zA...Z) has until
  5626   now. COMPATIBILITY: This obviously changes the parsing of some
  5627   terms, especially where a symbol has been used as a binder, say
  5628   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5629   as an identifier.  Fix it by inserting a space around former
  5630   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5631   existing theory and ML files.
  5632 
  5633 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5634 
  5635 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5636   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5637   a normal (but invisible) letter. For multiple letter subscripts repeat
  5638   \<^isub> like this: x\<^isub>1\<^isub>2.
  5639 
  5640 * Pure: There are now sub-/superscripts that can span more than one
  5641   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5642   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5643   superscript. The new control characters are not identifier parts.
  5644 
  5645 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5646   content of "..." to the latex file instead of \isacntrl... . The "..."
  5647   may consist of any printable characters excluding the end bracket >.
  5648 
  5649 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5650   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5651   declare constants "final", which prevents their being given a definition
  5652   later.  It is useful for constants whose behaviour is fixed axiomatically
  5653   rather than definitionally, such as the meta-logic connectives.
  5654 
  5655 * Pure: 'instance' now handles general arities with general sorts
  5656   (i.e. intersections of classes),
  5657 
  5658 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5659   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5660   It can be changed to alter the colors/layout of generated pages.
  5661 
  5662 
  5663 *** Isar ***
  5664 
  5665 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5666   cut_tac, subgoal_tac and thin_tac:
  5667   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5668     locales are no longer forced to write Isar proof scripts.
  5669     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5670     emulations.
  5671   - INCOMPATIBILITY: names of variables to be instantiated may no
  5672     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5673     This is consistent with the instantiation attribute "where".
  5674 
  5675 * Attributes "where" and "of":
  5676   - Now take type variables of instantiated theorem into account when reading
  5677     the instantiation string.  This fixes a bug that caused instantiated
  5678     theorems to have too special types in some circumstances.
  5679   - "where" permits explicit instantiations of type variables.
  5680 
  5681 * Calculation commands "moreover" and "also" no longer interfere with
  5682   current facts ("this"), admitting arbitrary combinations with "then"
  5683   and derived forms.
  5684 
  5685 * Locales:
  5686   - Goal statements involving the context element "includes" no longer
  5687     generate theorems with internal delta predicates (those ending on
  5688     "_axioms") in the premise.
  5689     Resolve particular premise with <locale>.intro to obtain old form.
  5690   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5691     specification and "includes" elements in goal statement.
  5692   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5693     [intro?] and [elim?] (respectively) by default.
  5694   - Experimental command for instantiation of locales in proof contexts:
  5695         instantiate <label>[<attrs>]: <loc>
  5696     Instantiates locale <loc> and adds all its theorems to the current context
  5697     taking into account their attributes.  Label and attrs are optional
  5698     modifiers, like in theorem declarations.  If present, names of
  5699     instantiated theorems are qualified with <label>, and the attributes
  5700     <attrs> are applied after any attributes these theorems might have already.
  5701       If the locale has assumptions, a chained fact of the form
  5702     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5703     are derived.  The command does not support old-style locales declared
  5704     with "locale (open)".
  5705       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5706 
  5707 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5708   (Isar) contexts.
  5709 
  5710 
  5711 *** HOL ***
  5712 
  5713 * Proof import: new image HOL4 contains the imported library from
  5714   the HOL4 system with about 2500 theorems. It is imported by
  5715   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5716   can be used like any other Isabelle image.  See
  5717   HOL/Import/HOL/README for more information.
  5718 
  5719 * Simplifier:
  5720   - Much improved handling of linear and partial orders.
  5721     Reasoners for linear and partial orders are set up for type classes
  5722     "linorder" and "order" respectively, and are added to the default simpset
  5723     as solvers.  This means that the simplifier can build transitivity chains
  5724     to solve goals from the assumptions.
  5725   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5726     of blast or auto after simplification become unnecessary because the goal
  5727     is solved by simplification already.
  5728 
  5729 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5730     all proved in axiomatic type classes for semirings, rings and fields.
  5731 
  5732 * Numerics:
  5733   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5734     now formalized using the Ring_and_Field theory mentioned above.
  5735   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5736     than before, because now they are set up once in a generic manner.
  5737   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5738     Look for the general versions in Ring_and_Field (and Power if they concern
  5739     exponentiation).
  5740 
  5741 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5742 
  5743 * Records:
  5744   - Record types are now by default printed with their type abbreviation
  5745     instead of the list of all field types. This can be configured via
  5746     the reference "print_record_type_abbr".
  5747   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5748     (not enabled by default).
  5749   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5750     EX x. x = sel r to True (not enabled by default).
  5751   - Tactic "record_split_simp_tac" to split and simplify records added.
  5752 
  5753 * 'specification' command added, allowing for definition by
  5754   specification.  There is also an 'ax_specification' command that
  5755   introduces the new constants axiomatically.
  5756 
  5757 * arith(_tac) is now able to generate counterexamples for reals as well.
  5758 
  5759 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5760 
  5761 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5762   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5763 
  5764 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5765   matrix theory to linear programming.
  5766 
  5767 * Unions and Intersections:
  5768   The latex output syntax of UN and INT has been changed
  5769   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5770   i.e. the index formulae has become a subscript.
  5771   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5772 
  5773 * Unions and Intersections over Intervals:
  5774   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5775   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5776   like in normal math, and corresponding versions for < and for intersection.
  5777 
  5778 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5779   lexicographic dictonary ordering has been added as "lexord".
  5780 
  5781 * ML: the legacy theory structures Int and List have been removed. They had
  5782   conflicted with ML Basis Library structures having the same names.
  5783 
  5784 * 'refute' command added to search for (finite) countermodels.  Only works
  5785   for a fragment of HOL.  The installation of an external SAT solver is
  5786   highly recommended.  See "HOL/Refute.thy" for details.
  5787 
  5788 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5789   formulae under an assignment of free variables to random values.
  5790   In contrast to 'refute', it can deal with inductive datatypes,
  5791   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5792   for examples.
  5793 
  5794 
  5795 *** HOLCF ***
  5796 
  5797 * Streams now come with concatenation and are part of the HOLCF image
  5798 
  5799 
  5800 
  5801 New in Isabelle2003 (May 2003)
  5802 ------------------------------
  5803 
  5804 *** General ***
  5805 
  5806 * Provers/simplifier:
  5807 
  5808   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5809     Assumptions are now subject to complete mutual simplification,
  5810     not just from left to right. The simplifier now preserves
  5811     the order of assumptions.
  5812 
  5813     Potential INCOMPATIBILITY:
  5814 
  5815     -- simp sometimes diverges where the old version did
  5816        not, e.g. invoking simp on the goal
  5817 
  5818         [| P (f x); y = x; f x = f y |] ==> Q
  5819 
  5820        now gives rise to the infinite reduction sequence
  5821 
  5822         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5823 
  5824        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5825        kind of problem.
  5826 
  5827     -- Tactics combining classical reasoner and simplification (such as auto)
  5828        are also affected by this change, because many of them rely on
  5829        simp. They may sometimes diverge as well or yield a different numbers
  5830        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5831        in case of problems. Sometimes subsequent calls to the classical
  5832        reasoner will fail because a preceeding call to the simplifier too
  5833        eagerly simplified the goal, e.g. deleted redundant premises.
  5834 
  5835   - The simplifier trace now shows the names of the applied rewrite rules
  5836 
  5837   - You can limit the number of recursive invocations of the simplifier
  5838     during conditional rewriting (where the simplifie tries to solve the
  5839     conditions before applying the rewrite rule):
  5840     ML "simp_depth_limit := n"
  5841     where n is an integer. Thus you can force termination where previously
  5842     the simplifier would diverge.
  5843 
  5844   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5845 
  5846   - No longer aborts on failed congruence proof.  Instead, the
  5847     congruence is ignored.
  5848 
  5849 * Pure: New generic framework for extracting programs from constructive
  5850   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5851   as HOL/Extraction for some case studies.
  5852 
  5853 * Pure: The main goal of the proof state is no longer shown by default, only
  5854 the subgoals. This behaviour is controlled by a new flag.
  5855    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5856 (ML: Proof.show_main_goal).
  5857 
  5858 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5859 rules whose conclusion matches subgoal 1:
  5860       PG menu: Isabelle/Isar -> Show me -> matching rules
  5861 The rules are ordered by how closely they match the subgoal.
  5862 In particular, rules that solve a subgoal outright are displayed first
  5863 (or rather last, the way they are printed).
  5864 (ML: ProofGeneral.print_intros())
  5865 
  5866 * Pure: New flag trace_unify_fail causes unification to print
  5867 diagnostic information (PG: in trace buffer) when it fails. This is
  5868 useful for figuring out why single step proofs like rule, erule or
  5869 assumption failed.
  5870 
  5871 * Pure: Locale specifications now produce predicate definitions
  5872 according to the body of text (covering assumptions modulo local
  5873 definitions); predicate "loc_axioms" covers newly introduced text,
  5874 while "loc" is cumulative wrt. all included locale expressions; the
  5875 latter view is presented only on export into the global theory
  5876 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5877 on the old view without predicates;
  5878 
  5879 * Pure: predefined locales "var" and "struct" are useful for sharing
  5880 parameters (as in CASL, for example); just specify something like
  5881 ``var x + var y + struct M'' as import;
  5882 
  5883 * Pure: improved thms_containing: proper indexing of facts instead of
  5884 raw theorems; check validity of results wrt. current name space;
  5885 include local facts of proof configuration (also covers active
  5886 locales), cover fixed variables in index; may use "_" in term
  5887 specification; an optional limit for the number of printed facts may
  5888 be given (the default is 40);
  5889 
  5890 * Pure: disallow duplicate fact bindings within new-style theory files
  5891 (batch-mode only);
  5892 
  5893 * Provers: improved induct method: assumptions introduced by case
  5894 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5895 the goal statement); "foo" still refers to all facts collectively;
  5896 
  5897 * Provers: the function blast.overloaded has been removed: all constants
  5898 are regarded as potentially overloaded, which improves robustness in exchange
  5899 for slight decrease in efficiency;
  5900 
  5901 * Provers/linorder: New generic prover for transitivity reasoning over
  5902 linear orders.  Note: this prover is not efficient!
  5903 
  5904 * Isar: preview of problems to finish 'show' now produce an error
  5905 rather than just a warning (in interactive mode);
  5906 
  5907 
  5908 *** HOL ***
  5909 
  5910 * arith(_tac)
  5911 
  5912  - Produces a counter example if it cannot prove a goal.
  5913    Note that the counter example may be spurious if the goal is not a formula
  5914    of quantifier-free linear arithmetic.
  5915    In ProofGeneral the counter example appears in the trace buffer.
  5916 
  5917  - Knows about div k and mod k where k is a numeral of type nat or int.
  5918 
  5919  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5920    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5921    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5922 
  5923 * simp's arithmetic capabilities have been enhanced a bit: it now
  5924 takes ~= in premises into account (by performing a case split);
  5925 
  5926 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5927 are distributed over a sum of terms;
  5928 
  5929 * New tactic "trans_tac" and method "trans" instantiate
  5930 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5931 "<=", "<" and "=").
  5932 
  5933 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5934 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5935 
  5936 * 'typedef' command has new option "open" to suppress the set
  5937 definition;
  5938 
  5939 * functions Min and Max on finite sets have been introduced (theory
  5940 Finite_Set);
  5941 
  5942 * attribute [symmetric] now works for relations as well; it turns
  5943 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5944 
  5945 * induct over a !!-quantified statement (say !!x1..xn):
  5946   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5947 
  5948 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5949 %x. None. Warning: empty_def now refers to the previously hidden definition
  5950 of the empty set.
  5951 
  5952 * Algebra: formalization of classical algebra.  Intended as base for
  5953 any algebraic development in Isabelle.  Currently covers group theory
  5954 (up to Sylow's theorem) and ring theory (Universal Property of
  5955 Univariate Polynomials).  Contributions welcome;
  5956 
  5957 * GroupTheory: deleted, since its material has been moved to Algebra;
  5958 
  5959 * Complex: new directory of the complex numbers with numeric constants,
  5960 nonstandard complex numbers, and some complex analysis, standard and
  5961 nonstandard (Jacques Fleuriot);
  5962 
  5963 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  5964 
  5965 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  5966 Fleuriot);
  5967 
  5968 * Real/HahnBanach: updated and adapted to locales;
  5969 
  5970 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  5971 Gray and Kramer);
  5972 
  5973 * UNITY: added the Meier-Sanders theory of progress sets;
  5974 
  5975 * MicroJava: bytecode verifier and lightweight bytecode verifier
  5976 as abstract algorithms, instantiated to the JVM;
  5977 
  5978 * Bali: Java source language formalization. Type system, operational
  5979 semantics, axiomatic semantics. Supported language features:
  5980 classes, interfaces, objects,virtual methods, static methods,
  5981 static/instance fields, arrays, access modifiers, definite
  5982 assignment, exceptions.
  5983 
  5984 
  5985 *** ZF ***
  5986 
  5987 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  5988 universe, etc.);
  5989 
  5990 * Main ZF: virtually all theories converted to new-style format;
  5991 
  5992 
  5993 *** ML ***
  5994 
  5995 * Pure: Tactic.prove provides sane interface for internal proofs;
  5996 omits the infamous "standard" operation, so this is more appropriate
  5997 than prove_goalw_cterm in many situations (e.g. in simprocs);
  5998 
  5999 * Pure: improved error reporting of simprocs;
  6000 
  6001 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  6002 up simprocs;
  6003 
  6004 
  6005 *** Document preparation ***
  6006 
  6007 * uses \par instead of \\ for line breaks in theory text. This may
  6008 shift some page breaks in large documents. To get the old behaviour
  6009 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  6010 
  6011 * minimized dependencies of isabelle.sty and isabellesym.sty on
  6012 other packages
  6013 
  6014 * \<euro> now needs package babel/greek instead of marvosym (which
  6015 broke \Rightarrow)
  6016 
  6017 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  6018 textcomp package)
  6019 
  6020 
  6021 
  6022 New in Isabelle2002 (March 2002)
  6023 --------------------------------
  6024 
  6025 *** Document preparation ***
  6026 
  6027 * greatly simplified document preparation setup, including more
  6028 graceful interpretation of isatool usedir -i/-d/-D options, and more
  6029 instructive isatool mkdir; users should basically be able to get
  6030 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  6031 users may run a separate document processing stage manually like this:
  6032 "isatool usedir -D output HOL Test && isatool document Test/output";
  6033 
  6034 * theory dependency graph may now be incorporated into documents;
  6035 isatool usedir -g true will produce session_graph.eps/.pdf for use
  6036 with \includegraphics of LaTeX;
  6037 
  6038 * proper spacing of consecutive markup elements, especially text
  6039 blocks after section headings;
  6040 
  6041 * support bold style (for single symbols only), input syntax is like
  6042 this: "\<^bold>\<alpha>" or "\<^bold>A";
  6043 
  6044 * \<bullet> is now output as bold \cdot by default, which looks much
  6045 better in printed text;
  6046 
  6047 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  6048 note that these symbols are currently unavailable in Proof General /
  6049 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  6050 
  6051 * isatool latex no longer depends on changed TEXINPUTS, instead
  6052 isatool document copies the Isabelle style files to the target
  6053 location;
  6054 
  6055 
  6056 *** Isar ***
  6057 
  6058 * Pure/Provers: improved proof by cases and induction;
  6059   - 'case' command admits impromptu naming of parameters (such as
  6060     "case (Suc n)");
  6061   - 'induct' method divinates rule instantiation from the inductive
  6062     claim; no longer requires excessive ?P bindings for proper
  6063     instantiation of cases;
  6064   - 'induct' method properly enumerates all possibilities of set/type
  6065     rules; as a consequence facts may be also passed through *type*
  6066     rules without further ado;
  6067   - 'induct' method now derives symbolic cases from the *rulified*
  6068     rule (before it used to rulify cases stemming from the internal
  6069     atomized version); this means that the context of a non-atomic
  6070     statement becomes is included in the hypothesis, avoiding the
  6071     slightly cumbersome show "PROP ?case" form;
  6072   - 'induct' may now use elim-style induction rules without chaining
  6073     facts, using ``missing'' premises from the goal state; this allows
  6074     rules stemming from inductive sets to be applied in unstructured
  6075     scripts, while still benefitting from proper handling of non-atomic
  6076     statements; NB: major inductive premises need to be put first, all
  6077     the rest of the goal is passed through the induction;
  6078   - 'induct' proper support for mutual induction involving non-atomic
  6079     rule statements (uses the new concept of simultaneous goals, see
  6080     below);
  6081   - append all possible rule selections, but only use the first
  6082     success (no backtracking);
  6083   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  6084   - undeclared rule case names default to numbers 1, 2, 3, ...;
  6085   - added 'print_induct_rules' (covered by help item in recent Proof
  6086     General versions);
  6087   - moved induct/cases attributes to Pure, methods to Provers;
  6088   - generic method setup instantiated for FOL and HOL;
  6089 
  6090 * Pure: support multiple simultaneous goal statements, for example
  6091 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  6092 meta-level mechanism, this acts as if several individual goals had
  6093 been stated separately; in particular common proof methods need to be
  6094 repeated in order to cover all claims; note that a single elimination
  6095 step is *not* sufficient to establish the two conjunctions, so this
  6096 fails:
  6097 
  6098   assume "A & B" then have A and B ..   (*".." fails*)
  6099 
  6100 better use "obtain" in situations as above; alternative refer to
  6101 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  6102 
  6103 * Pure: proper integration with ``locales''; unlike the original
  6104 version by Florian Kammller, Isar locales package high-level proof
  6105 contexts rather than raw logical ones (e.g. we admit to include
  6106 attributes everywhere); operations on locales include merge and
  6107 rename; support for implicit arguments (``structures''); simultaneous
  6108 type-inference over imports and text; see also HOL/ex/Locales.thy for
  6109 some examples;
  6110 
  6111 * Pure: the following commands have been ``localized'', supporting a
  6112 target locale specification "(in name)": 'lemma', 'theorem',
  6113 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  6114 stored both within the locale and at the theory level (exported and
  6115 qualified by the locale name);
  6116 
  6117 * Pure: theory goals may now be specified in ``long'' form, with
  6118 ad-hoc contexts consisting of arbitrary locale elements. for example
  6119 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  6120 definitions may be given, too); the result is a meta-level rule with
  6121 the context elements being discharged in the obvious way;
  6122 
  6123 * Pure: new proof command 'using' allows to augment currently used
  6124 facts after a goal statement ('using' is syntactically analogous to
  6125 'apply', but acts on the goal's facts only); this allows chained facts
  6126 to be separated into parts given before and after a claim, as in
  6127 ``from a and b have C using d and e <proof>'';
  6128 
  6129 * Pure: renamed "antecedent" case to "rule_context";
  6130 
  6131 * Pure: new 'judgment' command records explicit information about the
  6132 object-logic embedding (used by several tools internally); no longer
  6133 use hard-wired "Trueprop";
  6134 
  6135 * Pure: added 'corollary' command;
  6136 
  6137 * Pure: fixed 'token_translation' command;
  6138 
  6139 * Pure: removed obsolete 'exported' attribute;
  6140 
  6141 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  6142 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  6143 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  6144 
  6145 * Pure: method 'atomize' presents local goal premises as object-level
  6146 statements (atomic meta-level propositions); setup controlled via
  6147 rewrite rules declarations of 'atomize' attribute; example
  6148 application: 'induct' method with proper rule statements in improper
  6149 proof *scripts*;
  6150 
  6151 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  6152 now consider the syntactic context of assumptions, giving a better
  6153 chance to get type-inference of the arguments right (this is
  6154 especially important for locales);
  6155 
  6156 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  6157 mode;
  6158 
  6159 * Pure/obtain: the formal conclusion "thesis", being marked as
  6160 ``internal'', may no longer be reference directly in the text;
  6161 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  6162 situations;
  6163 
  6164 * Pure: generic 'sym' attribute which declares a rule both as pure
  6165 'elim?' and for the 'symmetric' operation;
  6166 
  6167 * Pure: marginal comments ``--'' may now occur just anywhere in the
  6168 text; the fixed correlation with particular command syntax has been
  6169 discontinued;
  6170 
  6171 * Pure: new method 'rules' is particularly well-suited for proof
  6172 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  6173 but often produces more compact proof terms with less detours;
  6174 
  6175 * Pure/Provers/classical: simplified integration with pure rule
  6176 attributes and methods; the classical "intro?/elim?/dest?"
  6177 declarations coincide with the pure ones; the "rule" method no longer
  6178 includes classically swapped intros; "intro" and "elim" methods no
  6179 longer pick rules from the context; also got rid of ML declarations
  6180 AddXIs/AddXEs/AddXDs; all of this has some potential for
  6181 INCOMPATIBILITY;
  6182 
  6183 * Provers/classical: attribute 'swapped' produces classical inversions
  6184 of introduction rules;
  6185 
  6186 * Provers/simplifier: 'simplified' attribute may refer to explicit
  6187 rules instead of full simplifier context; 'iff' attribute handles
  6188 conditional rules;
  6189 
  6190 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  6191 
  6192 * HOL: 'recdef' now fails on unfinished automated proofs, use
  6193 "(permissive)" option to recover old behavior;
  6194 
  6195 * HOL: 'inductive' no longer features separate (collective) attributes
  6196 for 'intros' (was found too confusing);
  6197 
  6198 * HOL: properly declared induction rules less_induct and
  6199 wf_induct_rule;
  6200 
  6201 
  6202 *** HOL ***
  6203 
  6204 * HOL: moved over to sane numeral syntax; the new policy is as
  6205 follows:
  6206 
  6207   - 0 and 1 are polymorphic constants, which are defined on any
  6208   numeric type (nat, int, real etc.);
  6209 
  6210   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  6211   binary representation internally;
  6212 
  6213   - type nat has special constructor Suc, and generally prefers Suc 0
  6214   over 1::nat and Suc (Suc 0) over 2::nat;
  6215 
  6216 This change may cause significant problems of INCOMPATIBILITY; here
  6217 are some hints on converting existing sources:
  6218 
  6219   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  6220   entities, so expressions involving "-" (unary or binary minus) need
  6221   to be spaced properly;
  6222 
  6223   - existing occurrences of "1" may need to be constraint "1::nat" or
  6224   even replaced by Suc 0; similar for old "2";
  6225 
  6226   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  6227 
  6228   - remove all special provisions on numerals in proofs;
  6229 
  6230 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  6231 representation (depends on bin_arith_simps in the default context);
  6232 
  6233 * HOL: symbolic syntax for x^2 (numeral 2);