NEWS
author haftmann
Tue Aug 09 08:06:15 2011 +0200 (2011-08-09)
changeset 44103 cedaca00789f
parent 44086 c0847967a25a
child 44136 e63ad7d5158d
permissions -rw-r--r--
more uniform naming scheme for Inf/INF and Sup/SUP lemmas
     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) has been discontinued.
    26 Note that the path element ~~ may be used to reference theories in the
    27 Isabelle home folder -- for instance, "~~/src/HOL/Library/FuncSet".
    28 INCOMPATIBILITY.
    29 
    30 * Various optional external tools are referenced more robustly and
    31 uniformly by explicit Isabelle settings as follows:
    32 
    33   ISABELLE_CSDP   (formerly CSDP_EXE)
    34   ISABELLE_GHC    (formerly EXEC_GHC or GHC_PATH)
    35   ISABELLE_OCAML  (formerly EXEC_OCAML)
    36   ISABELLE_SWIPL  (formerly EXEC_SWIPL)
    37   ISABELLE_YAP    (formerly EXEC_YAP)
    38 
    39 Note that automated detection from the file-system or search path has
    40 been discontinued.  INCOMPATIBILITY.
    41 
    42 * Name space: former unsynchronized references are now proper
    43 configuration options, with more conventional names:
    44 
    45   long_names   ~> names_long
    46   short_names  ~> names_short
    47   unique_names ~> names_unique
    48 
    49 Minor INCOMPATIBILITY, need to declare options in context like this:
    50 
    51   declare [[names_unique = false]]
    52 
    53 * Literal facts `prop` may contain dummy patterns, e.g. `_ = _`.  Note
    54 that the result needs to be unique, which means fact specifications
    55 may have to be refined after enriching a proof context.
    56 
    57 * Isabelle/Isar reference manual provides more formal references in
    58 syntax diagrams.
    59 
    60 
    61 *** HOL ***
    62 
    63 * Classes bot and top require underlying partial order rather than preorder:
    64 uniqueness of bot and top is guaranteed.  INCOMPATIBILITY.
    65 
    66 * Class complete_lattice: generalized a couple of lemmas from sets;
    67 generalized theorems INF_cong and SUP_cong.  New type classes for complete
    68 boolean algebras and complete linear orders.  Lemmas Inf_less_iff,
    69 less_Sup_iff, INF_less_iff, less_SUP_iff now reside in class complete_linorder.
    70 Changed proposition of lemmas Inf_fun_def, Sup_fun_def, Inf_apply, Sup_apply.
    71 Redundant lemmas Inf_singleton, Sup_singleton, Inf_binary, Sup_binary,
    72 INF_eq, SUP_eq, INF_UNIV_range, SUP_UNIV_range, Int_eq_Inter,
    73 INTER_eq_Inter_image, Inter_def, INT_eq, Un_eq_Union, UNION_eq_Union_image,
    74 Union_def, UN_singleton, UN_eq have been discarded.
    75 More consistent and less misunderstandable names:
    76   INFI_def ~> INF_def
    77   SUPR_def ~> SUP_def
    78   INF_leI ~> INF_lower
    79   INF_leI2 ~> INF_lower2
    80   le_INFI ~> INF_greatest
    81   le_SUPI ~> SUP_upper
    82   le_SUPI2 ~> SUP_upper2
    83   SUP_leI ~> SUP_least
    84   INFI_bool_eq ~> INF_bool_eq
    85   SUPR_bool_eq ~> SUP_bool_eq
    86   INFI_apply ~> INF_apply
    87   SUPR_apply ~> SUP_apply
    88   INTER_def ~> INTER_eq
    89   UNION_def ~> UNION_eq
    90 
    91 INCOMPATIBILITY.
    92 
    93 * Theorem collections ball_simps and bex_simps do not contain theorems referring
    94 to UNION any longer;  these have been moved to collection UN_ball_bex_simps.
    95 INCOMPATIBILITY.
    96 
    97 * Archimedean_Field.thy:
    98     floor now is defined as parameter of a separate type class floor_ceiling.
    99  
   100 * Finite_Set.thy: more coherent development of fold_set locales:
   101 
   102     locale fun_left_comm ~> locale comp_fun_commute
   103     locale fun_left_comm_idem ~> locale comp_fun_idem
   104     
   105 Both use point-free characterisation; interpretation proofs may need adjustment.
   106 INCOMPATIBILITY.
   107 
   108 * Code generation:
   109   - theory Library/Code_Char_ord provides native ordering of characters
   110     in the target language.
   111   - commands code_module and code_library are legacy, use export_code instead. 
   112   - method evaluation is legacy, use method eval instead.
   113   - legacy evaluator "SML" is deactivated by default. To activate it, add the following
   114     line in your theory:
   115       setup {* Value.add_evaluator ("SML", Codegen.eval_term) *}
   116  
   117 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
   118 
   119 * Nitpick:
   120   - Added "need" and "total_consts" options.
   121   - Reintroduced "show_skolems" option by popular demand.
   122   - Renamed attribute: nitpick_def ~> nitpick_unfold.
   123     INCOMPATIBILITY.
   124 
   125 * Sledgehammer:
   126   - sledgehammer available_provers ~> sledgehammer supported_provers.
   127     INCOMPATIBILITY.
   128   - Added support for SNARK and ToFoF-E on SystemOnTPTP and for simply typed
   129     TPTP problems (TFF).
   130   - Added "preplay_timeout", "slicing", "type_enc", "sound", "max_mono_iters",
   131     and "max_new_mono_instances" options.
   132   - Removed "explicit_apply" and "full_types" options as well as "Full Types"
   133     Proof General menu item. INCOMPATIBILITY.
   134 
   135 * Metis:
   136   - Removed "metisF" -- use "metis" instead. INCOMPATIBILITY.
   137   - Obsoleted "metisFT" -- use "metis (full_types)" instead. INCOMPATIBILITY.
   138 
   139 * "try":
   140   - Renamed "try_methods" and added "simp:", "intro:", "dest:", and "elim:"
   141     options. INCOMPATIBILITY.
   142   - Introduced "try" that not only runs "try_methods" but also "solve_direct",
   143     "sledgehammer", "quickcheck", and "nitpick".
   144 
   145 * Quickcheck:
   146   - Added "eval" option to evaluate terms for the found counterexample
   147     (currently only supported by the default (exhaustive) tester)
   148   - Added post-processing of terms to obtain readable counterexamples
   149     (currently only supported by the default (exhaustive) tester)
   150   - New counterexample generator quickcheck[narrowing] enables
   151     narrowing-based testing.
   152     It requires that the Glasgow Haskell compiler is installed and
   153     its location is known to Isabelle with the environment variable
   154     ISABELLE_GHC.
   155   - Removed quickcheck tester "SML" based on the SML code generator
   156     from HOL-Library
   157 
   158 * Function package: discontinued option "tailrec".
   159 INCOMPATIBILITY. Use partial_function instead.
   160 
   161 * HOL-Probability:
   162   - Caratheodory's extension lemma is now proved for ring_of_sets.
   163   - Infinite products of probability measures are now available.
   164   - Use extended reals instead of positive extended reals.
   165     INCOMPATIBILITY.
   166 
   167 * Old recdef package has been moved to Library/Old_Recdef.thy, where it
   168 must be loaded explicitly.  INCOMPATIBILITY.
   169 
   170 * Well-founded recursion combinator "wfrec" has been moved to
   171 Library/Wfrec.thy. INCOMPATIBILITY.
   172 
   173 * Theory Library/Nat_Infinity has been renamed to Library/Extended_Nat.
   174 The names of the following types and constants have changed:
   175   inat (type) ~> enat
   176   Fin         ~> enat
   177   Infty       ~> infinity (overloaded)
   178   iSuc        ~> eSuc
   179   the_Fin     ~> the_enat
   180 Every theorem name containing "inat", "Fin", "Infty", or "iSuc" has
   181 been renamed accordingly.
   182 
   183 * Limits.thy: Type "'a net" has been renamed to "'a filter", in
   184 accordance with standard mathematical terminology. INCOMPATIBILITY.
   185 
   186 
   187 *** Document preparation ***
   188 
   189 * Discontinued special treatment of hard tabulators, which are better
   190 avoided in the first place.  Implicit tab-width is 1.
   191 
   192 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
   193 isar-ref manual.
   194 
   195 * Antiquotation @{value} evaluates the given term and presents its result.
   196 
   197 * Localized \isabellestyle switch can be used within blocks or groups
   198 like this:
   199 
   200   \isabellestyle{it}  %preferred default
   201   {\isabellestylett @{text "typewriter stuff"}}
   202 
   203 * New term style "isub" as ad-hoc conversion of variables x1, y23 into
   204 subscripted form x\<^isub>1, y\<^isub>2\<^isub>3.
   205 
   206 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
   207 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
   208 
   209 
   210 *** ML ***
   211 
   212 * The inner syntax of sort/type/term/prop supports inlined YXML
   213 representations within quoted string tokens.  By encoding logical
   214 entities via Term_XML (in ML or Scala) concrete syntax can be
   215 bypassed, which is particularly useful for producing bits of text
   216 under external program control.
   217 
   218 * Antiquotations for ML and document preparation are managed as theory
   219 data, which requires explicit setup.
   220 
   221 * Isabelle_Process.is_active allows tools to check if the official
   222 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
   223 (better known as Proof General).
   224 
   225 * Structure Proof_Context follows standard naming scheme.  Old
   226 ProofContext is still available for some time as legacy alias.
   227 
   228 * Structure Timing provides various operations for timing; supersedes
   229 former start_timing/end_timing etc.
   230 
   231 * Path.print is the official way to show file-system paths to users
   232 (including quotes etc.).
   233 
   234 * Inner syntax: identifiers in parse trees of generic categories
   235 "logic", "aprop", "idt" etc. carry position information (disguised as
   236 type constraints).  Occasional INCOMPATIBILITY with non-compliant
   237 translations that choke on unexpected type constraints.  Positions can
   238 be stripped in ML translations via Syntax.strip_positions /
   239 Syntax.strip_positions_ast, or via the syntax constant
   240 "_strip_positions" within parse trees.  As last resort, positions can
   241 be disabled via the configuration option Syntax.positions, which is
   242 called "syntax_positions" in Isar attribute syntax.
   243 
   244 * Discontinued special status of various ML structures that contribute
   245 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
   246 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
   247 refer directly to Ast.Constant, Lexicon.is_identifier,
   248 Syntax_Trans.mk_binder_tr etc.
   249 
   250 * Typed print translation: discontinued show_sorts argument, which is
   251 already available via context of "advanced" translation.
   252 
   253 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
   254 goal states; body tactic needs to address all subgoals uniformly.
   255 
   256 * Slightly more special eq_list/eq_set, with shortcut involving
   257 pointer equality (assumes that eq relation is reflexive).
   258 
   259 * Classical tactics use proper Proof.context instead of historic types
   260 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
   261 operate directly on Proof.context.  Raw type claset retains its use as
   262 snapshot of the classical context, which can be recovered via
   263 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
   264 INCOMPATIBILITY, classical tactics and derived proof methods require
   265 proper Proof.context.
   266 
   267 * Scala layer provides JVM method invocation service for static
   268 methods of type (String)String, see Invoke_Scala.method in ML.
   269 For example:
   270 
   271   Invoke_Scala.method "java.lang.System.getProperty" "java.home"
   272 
   273 
   274 
   275 New in Isabelle2011 (January 2011)
   276 ----------------------------------
   277 
   278 *** General ***
   279 
   280 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
   281 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
   282 useful tooltips and hyperlinks produced from its static analysis.  The
   283 bundled component provides an executable Isabelle tool that can be run
   284 like this:
   285 
   286   Isabelle2011/bin/isabelle jedit
   287 
   288 * Significantly improved Isabelle/Isar implementation manual.
   289 
   290 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
   291 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
   292 while the default heap location within that directory lacks that extra
   293 suffix.  This isolates multiple Isabelle installations from each
   294 other, avoiding problems with old settings in new versions.
   295 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
   296 
   297 * Source files are always encoded as UTF-8, instead of old-fashioned
   298 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   299 the following package declarations:
   300 
   301   \usepackage[utf8]{inputenc}
   302   \usepackage{textcomp}
   303 
   304 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   305 a Unicode character is treated as a single symbol, not a sequence of
   306 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   307 contain symbols without further backslash escapes, Unicode can now be
   308 used here as well.  Recall that Symbol.explode in ML provides a
   309 consistent view on symbols, while raw explode (or String.explode)
   310 merely give a byte-oriented representation.
   311 
   312 * Theory loader: source files are primarily located via the master
   313 directory of each theory node (where the .thy file itself resides).
   314 The global load path is still partially available as legacy feature.
   315 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   316 explicit paths, relatively to the theory.
   317 
   318 * Special treatment of ML file names has been discontinued.
   319 Historically, optional extensions .ML or .sml were added on demand --
   320 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   321 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   322 
   323 * Various options that affect pretty printing etc. are now properly
   324 handled within the context via configuration options, instead of
   325 unsynchronized references or print modes.  There are both ML Config.T
   326 entities and Isar declaration attributes to access these.
   327 
   328   ML (Config.T)                 Isar (attribute)
   329 
   330   eta_contract                  eta_contract
   331   show_brackets                 show_brackets
   332   show_sorts                    show_sorts
   333   show_types                    show_types
   334   show_question_marks           show_question_marks
   335   show_consts                   show_consts
   336   show_abbrevs                  show_abbrevs
   337 
   338   Syntax.ast_trace              syntax_ast_trace
   339   Syntax.ast_stat               syntax_ast_stat
   340   Syntax.ambiguity_level        syntax_ambiguity_level
   341 
   342   Goal_Display.goals_limit      goals_limit
   343   Goal_Display.show_main_goal   show_main_goal
   344 
   345   Method.rule_trace             rule_trace
   346 
   347   Thy_Output.display            thy_output_display
   348   Thy_Output.quotes             thy_output_quotes
   349   Thy_Output.indent             thy_output_indent
   350   Thy_Output.source             thy_output_source
   351   Thy_Output.break              thy_output_break
   352 
   353 Note that corresponding "..._default" references in ML may only be
   354 changed globally at the ROOT session setup, but *not* within a theory.
   355 The option "show_abbrevs" supersedes the former print mode
   356 "no_abbrevs" with inverted meaning.
   357 
   358 * More systematic naming of some configuration options.
   359 INCOMPATIBILITY.
   360 
   361   trace_simp  ~>  simp_trace
   362   debug_simp  ~>  simp_debug
   363 
   364 * Support for real valued configuration options, using simplistic
   365 floating-point notation that coincides with the inner syntax for
   366 float_token.
   367 
   368 * Support for real valued preferences (with approximative PGIP type):
   369 front-ends need to accept "pgint" values in float notation.
   370 INCOMPATIBILITY.
   371 
   372 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   373 DejaVu Sans.
   374 
   375 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   376 
   377 
   378 *** Pure ***
   379 
   380 * Command 'type_synonym' (with single argument) replaces somewhat
   381 outdated 'types', which is still available as legacy feature for some
   382 time.
   383 
   384 * Command 'nonterminal' (with 'and' separated list of arguments)
   385 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   386 
   387 * Command 'notepad' replaces former 'example_proof' for
   388 experimentation in Isar without any result.  INCOMPATIBILITY.
   389 
   390 * Locale interpretation commands 'interpret' and 'sublocale' accept
   391 lists of equations to map definitions in a locale to appropriate
   392 entities in the context of the interpretation.  The 'interpretation'
   393 command already provided this functionality.
   394 
   395 * Diagnostic command 'print_dependencies' prints the locale instances
   396 that would be activated if the specified expression was interpreted in
   397 the current context.  Variant "print_dependencies!" assumes a context
   398 without interpretations.
   399 
   400 * Diagnostic command 'print_interps' prints interpretations in proofs
   401 in addition to interpretations in theories.
   402 
   403 * Discontinued obsolete 'global' and 'local' commands to manipulate
   404 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   405 Sign.root_path and Sign.local_path may be applied directly where this
   406 feature is still required for historical reasons.
   407 
   408 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   409 'definition' instead.
   410 
   411 * The "prems" fact, which refers to the accidental collection of
   412 foundational premises in the context, is now explicitly marked as
   413 legacy feature and will be discontinued soon.  Consider using "assms"
   414 of the head statement or reference facts by explicit names.
   415 
   416 * Document antiquotations @{class} and @{type} print classes and type
   417 constructors.
   418 
   419 * Document antiquotation @{file} checks file/directory entries within
   420 the local file system.
   421 
   422 
   423 *** HOL ***
   424 
   425 * Coercive subtyping: functions can be declared as coercions and type
   426 inference will add them as necessary upon input of a term.  Theory
   427 Complex_Main declares real :: nat => real and real :: int => real as
   428 coercions. A coercion function f is declared like this:
   429 
   430   declare [[coercion f]]
   431 
   432 To lift coercions through type constructors (e.g. from nat => real to
   433 nat list => real list), map functions can be declared, e.g.
   434 
   435   declare [[coercion_map map]]
   436 
   437 Currently coercion inference is activated only in theories including
   438 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   439 the configuration option "coercion_enabled", e.g. it can be enabled in
   440 other theories like this:
   441 
   442   declare [[coercion_enabled]]
   443 
   444 * Command 'partial_function' provides basic support for recursive
   445 function definitions over complete partial orders.  Concrete instances
   446 are provided for i) the option type, ii) tail recursion on arbitrary
   447 types, and iii) the heap monad of Imperative_HOL.  See
   448 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   449 for examples.
   450 
   451 * Function package: f.psimps rules are no longer implicitly declared
   452 as [simp].  INCOMPATIBILITY.
   453 
   454 * Datatype package: theorems generated for executable equality (class
   455 "eq") carry proper names and are treated as default code equations.
   456 
   457 * Inductive package: now offers command 'inductive_simps' to
   458 automatically derive instantiated and simplified equations for
   459 inductive predicates, similar to 'inductive_cases'.
   460 
   461 * Command 'enriched_type' allows to register properties of the
   462 functorial structure of types.
   463 
   464 * Improved infrastructure for term evaluation using code generator
   465 techniques, in particular static evaluation conversions.
   466 
   467 * Code generator: Scala (2.8 or higher) has been added to the target
   468 languages.
   469 
   470 * Code generator: globbing constant expressions "*" and "Theory.*"
   471 have been replaced by the more idiomatic "_" and "Theory._".
   472 INCOMPATIBILITY.
   473 
   474 * Code generator: export_code without explicit file declaration prints
   475 to standard output.  INCOMPATIBILITY.
   476 
   477 * Code generator: do not print function definitions for case
   478 combinators any longer.
   479 
   480 * Code generator: simplification with rules determined with
   481 src/Tools/Code/code_simp.ML and method "code_simp".
   482 
   483 * Code generator for records: more idiomatic representation of record
   484 types.  Warning: records are not covered by ancient SML code
   485 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   486 rep_datatype declaration helps to succeed then:
   487 
   488   record 'a foo = ...
   489   ...
   490   rep_datatype foo_ext ...
   491 
   492 * Records: logical foundation type for records does not carry a
   493 '_type' suffix any longer (obsolete due to authentic syntax).
   494 INCOMPATIBILITY.
   495 
   496 * Quickcheck now by default uses exhaustive testing instead of random
   497 testing.  Random testing can be invoked by "quickcheck [random]",
   498 exhaustive testing by "quickcheck [exhaustive]".
   499 
   500 * Quickcheck instantiates polymorphic types with small finite
   501 datatypes by default. This enables a simple execution mechanism to
   502 handle quantifiers and function equality over the finite datatypes.
   503 
   504 * Quickcheck random generator has been renamed from "code" to
   505 "random".  INCOMPATIBILITY.
   506 
   507 * Quickcheck now has a configurable time limit which is set to 30
   508 seconds by default. This can be changed by adding [timeout = n] to the
   509 quickcheck command. The time limit for Auto Quickcheck is still set
   510 independently.
   511 
   512 * Quickcheck in locales considers interpretations of that locale for
   513 counter example search.
   514 
   515 * Sledgehammer:
   516   - Added "smt" and "remote_smt" provers based on the "smt" proof
   517     method. See the Sledgehammer manual for details ("isabelle doc
   518     sledgehammer").
   519   - Renamed commands:
   520     sledgehammer atp_info ~> sledgehammer running_provers
   521     sledgehammer atp_kill ~> sledgehammer kill_provers
   522     sledgehammer available_atps ~> sledgehammer available_provers
   523     INCOMPATIBILITY.
   524   - Renamed options:
   525     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   526     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   527     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   528     (and "ms" and "min" are no longer supported)
   529     INCOMPATIBILITY.
   530 
   531 * Nitpick:
   532   - Renamed options:
   533     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   534     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   535     INCOMPATIBILITY.
   536   - Added support for partial quotient types.
   537   - Added local versions of the "Nitpick.register_xxx" functions.
   538   - Added "whack" option.
   539   - Allow registration of quotient types as codatatypes.
   540   - Improved "merge_type_vars" option to merge more types.
   541   - Removed unsound "fast_descrs" option.
   542   - Added custom symmetry breaking for datatypes, making it possible to reach
   543     higher cardinalities.
   544   - Prevent the expansion of too large definitions.
   545 
   546 * Proof methods "metis" and "meson" now have configuration options
   547 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   548 to diagnose these tools. E.g.
   549 
   550     using [[metis_trace = true]]
   551 
   552 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   553 manually as command 'solve_direct'.
   554 
   555 * The default SMT solver Z3 must be enabled explicitly (due to
   556 licensing issues) by setting the environment variable
   557 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   558 commercial applications, the SMT solver CVC3 is provided as fall-back;
   559 changing the SMT solver is done via the configuration option
   560 "smt_solver".
   561 
   562 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   563 i.e. "remote_cvc3" and "remote_z3".
   564 
   565 * Added basic SMT support for datatypes, records, and typedefs using
   566 the oracle mode (no proofs).  Direct support of pairs has been dropped
   567 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   568 support for a similar behavior).  Minor INCOMPATIBILITY.
   569 
   570 * Changed SMT configuration options:
   571   - Renamed:
   572     z3_proofs ~> smt_oracle (with inverted meaning)
   573     z3_trace_assms ~> smt_trace_used_facts
   574     INCOMPATIBILITY.
   575   - Added:
   576     smt_verbose
   577     smt_random_seed
   578     smt_datatypes
   579     smt_infer_triggers
   580     smt_monomorph_limit
   581     cvc3_options
   582     remote_cvc3_options
   583     remote_z3_options
   584     yices_options
   585 
   586 * Boogie output files (.b2i files) need to be declared in the theory
   587 header.
   588 
   589 * Simplification procedure "list_to_set_comprehension" rewrites list
   590 comprehensions applied to List.set to set comprehensions.  Occasional
   591 INCOMPATIBILITY, may be deactivated like this:
   592 
   593   declare [[simproc del: list_to_set_comprehension]]
   594 
   595 * Removed old version of primrec package.  INCOMPATIBILITY.
   596 
   597 * Removed simplifier congruence rule of "prod_case", as has for long
   598 been the case with "split".  INCOMPATIBILITY.
   599 
   600 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   601 
   602 * Removed [split_format ... and ... and ...] version of
   603 [split_format].  Potential INCOMPATIBILITY.
   604 
   605 * Predicate "sorted" now defined inductively, with nice induction
   606 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   607 
   608 * Constant "contents" renamed to "the_elem", to free the generic name
   609 contents for other uses.  INCOMPATIBILITY.
   610 
   611 * Renamed class eq and constant eq (for code generation) to class
   612 equal and constant equal, plus renaming of related facts and various
   613 tuning.  INCOMPATIBILITY.
   614 
   615 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   616 
   617 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   618 INCOMPATIBILITY.
   619 
   620 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   621 avoid confusion with finite sets.  INCOMPATIBILITY.
   622 
   623 * Abandoned locales equiv, congruent and congruent2 for equivalence
   624 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   625 for congruent(2)).
   626 
   627 * Some previously unqualified names have been qualified:
   628 
   629   types
   630     bool ~> HOL.bool
   631     nat ~> Nat.nat
   632 
   633   constants
   634     Trueprop ~> HOL.Trueprop
   635     True ~> HOL.True
   636     False ~> HOL.False
   637     op & ~> HOL.conj
   638     op | ~> HOL.disj
   639     op --> ~> HOL.implies
   640     op = ~> HOL.eq
   641     Not ~> HOL.Not
   642     The ~> HOL.The
   643     All ~> HOL.All
   644     Ex ~> HOL.Ex
   645     Ex1 ~> HOL.Ex1
   646     Let ~> HOL.Let
   647     If ~> HOL.If
   648     Ball ~> Set.Ball
   649     Bex ~> Set.Bex
   650     Suc ~> Nat.Suc
   651     Pair ~> Product_Type.Pair
   652     fst ~> Product_Type.fst
   653     snd ~> Product_Type.snd
   654     curry ~> Product_Type.curry
   655     op : ~> Set.member
   656     Collect ~> Set.Collect
   657 
   658 INCOMPATIBILITY.
   659 
   660 * More canonical naming convention for some fundamental definitions:
   661 
   662     bot_bool_eq ~> bot_bool_def
   663     top_bool_eq ~> top_bool_def
   664     inf_bool_eq ~> inf_bool_def
   665     sup_bool_eq ~> sup_bool_def
   666     bot_fun_eq  ~> bot_fun_def
   667     top_fun_eq  ~> top_fun_def
   668     inf_fun_eq  ~> inf_fun_def
   669     sup_fun_eq  ~> sup_fun_def
   670 
   671 INCOMPATIBILITY.
   672 
   673 * More stylized fact names:
   674 
   675   expand_fun_eq ~> fun_eq_iff
   676   expand_set_eq ~> set_eq_iff
   677   set_ext       ~> set_eqI
   678   nat_number    ~> eval_nat_numeral
   679 
   680 INCOMPATIBILITY.
   681 
   682 * Refactoring of code-generation specific operations in theory List:
   683 
   684   constants
   685     null ~> List.null
   686 
   687   facts
   688     mem_iff ~> member_def
   689     null_empty ~> null_def
   690 
   691 INCOMPATIBILITY.  Note that these were not supposed to be used
   692 regularly unless for striking reasons; their main purpose was code
   693 generation.
   694 
   695 Various operations from the Haskell prelude are used for generating
   696 Haskell code.
   697 
   698 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   699 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   700 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   701 
   702 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   703 "*" and "+" respectively.  INCOMPATIBILITY.
   704 
   705 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   706 "Sum_Type.Plus" instead.
   707 
   708 * Constant "split" has been merged with constant "prod_case"; names of
   709 ML functions, facts etc. involving split have been retained so far,
   710 though.  INCOMPATIBILITY.
   711 
   712 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   713 instead.  INCOMPATIBILITY.
   714 
   715 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   716 INCOMPATIBILITY.
   717 
   718 * Former theory Library/Enum is now part of the HOL-Main image.
   719 INCOMPATIBILITY: all constants of the Enum theory now have to be
   720 referred to by its qualified name.
   721 
   722   enum    ~>  Enum.enum
   723   nlists  ~>  Enum.nlists
   724   product ~>  Enum.product
   725 
   726 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   727 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   728 INCOMPATIBILITY.
   729 
   730 * Theory Library/SetsAndFunctions has been split into
   731 Library/Function_Algebras and Library/Set_Algebras; canonical names
   732 for instance definitions for functions; various improvements.
   733 INCOMPATIBILITY.
   734 
   735 * Theory Library/Multiset provides stable quicksort implementation of
   736 sort_key.
   737 
   738 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   739 INCOMPATIBILITY.
   740 
   741 * Session Multivariate_Analysis: introduced a type class for euclidean
   742 space.  Most theorems are now stated in terms of euclidean spaces
   743 instead of finite cartesian products.
   744 
   745   types
   746     real ^ 'n ~>  'a::real_vector
   747               ~>  'a::euclidean_space
   748               ~>  'a::ordered_euclidean_space
   749         (depends on your needs)
   750 
   751   constants
   752      _ $ _        ~> _ $$ _
   753      \<chi> x. _  ~> \<chi>\<chi> x. _
   754      CARD('n)     ~> DIM('a)
   755 
   756 Also note that the indices are now natural numbers and not from some
   757 finite type. Finite cartesian products of euclidean spaces, products
   758 of euclidean spaces the real and complex numbers are instantiated to
   759 be euclidean_spaces.  INCOMPATIBILITY.
   760 
   761 * Session Probability: introduced pextreal as positive extended real
   762 numbers.  Use pextreal as value for measures.  Introduce the
   763 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   764 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   765 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   766 
   767 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   768 INCOMPATIBILITY.
   769 
   770 * Session SPARK (with image HOL-SPARK) provides commands to load and
   771 prove verification conditions generated by the SPARK Ada program
   772 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   773 
   774 
   775 *** HOL-Algebra ***
   776 
   777 * Theorems for additive ring operations (locale abelian_monoid and
   778 descendants) are generated by interpretation from their multiplicative
   779 counterparts.  Names (in particular theorem names) have the mandatory
   780 qualifier 'add'.  Previous theorem names are redeclared for
   781 compatibility.
   782 
   783 * Structure "int_ring" is now an abbreviation (previously a
   784 definition).  This fits more natural with advanced interpretations.
   785 
   786 
   787 *** HOLCF ***
   788 
   789 * The domain package now runs in definitional mode by default: The
   790 former command 'new_domain' is now called 'domain'.  To use the domain
   791 package in its original axiomatic mode, use 'domain (unsafe)'.
   792 INCOMPATIBILITY.
   793 
   794 * The new class "domain" is now the default sort.  Class "predomain"
   795 is an unpointed version of "domain". Theories can be updated by
   796 replacing sort annotations as shown below.  INCOMPATIBILITY.
   797 
   798   'a::type ~> 'a::countable
   799   'a::cpo  ~> 'a::predomain
   800   'a::pcpo ~> 'a::domain
   801 
   802 * The old type class "rep" has been superseded by class "domain".
   803 Accordingly, users of the definitional package must remove any
   804 "default_sort rep" declarations.  INCOMPATIBILITY.
   805 
   806 * The domain package (definitional mode) now supports unpointed
   807 predomain argument types, as long as they are marked 'lazy'. (Strict
   808 arguments must be in class "domain".) For example, the following
   809 domain definition now works:
   810 
   811   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   812 
   813 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   814 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   815 'a option, and 'a list.  Additionally, it configures fixrec and the
   816 domain package to work with these types.  For example:
   817 
   818   fixrec isInl :: "('a + 'b) u -> tr"
   819     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   820 
   821   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   822 
   823 * The "(permissive)" option of fixrec has been replaced with a
   824 per-equation "(unchecked)" option. See
   825 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
   826 
   827 * The "bifinite" class no longer fixes a constant "approx"; the class
   828 now just asserts that such a function exists.  INCOMPATIBILITY.
   829 
   830 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
   831 defines an embedding of type 'a defl into udom by default; instances
   832 of "bifinite" and "domain" classes are available in
   833 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
   834 
   835 * The syntax "REP('a)" has been replaced with "DEFL('a)".
   836 
   837 * The predicate "directed" has been removed.  INCOMPATIBILITY.
   838 
   839 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
   840 
   841 * The function "cprod_map" has been renamed to "prod_map".
   842 INCOMPATIBILITY.
   843 
   844 * The monadic bind operator on each powerdomain has new binder syntax
   845 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
   846 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
   847 
   848 * The infix syntax for binary union on each powerdomain has changed
   849 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
   850 syntax.  INCOMPATIBILITY.
   851 
   852 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
   853 still supported as an input translation.
   854 
   855 * Renamed some theorems (the original names are also still available).
   856 
   857   expand_fun_below   ~> fun_below_iff
   858   below_fun_ext      ~> fun_belowI
   859   expand_cfun_eq     ~> cfun_eq_iff
   860   ext_cfun           ~> cfun_eqI
   861   expand_cfun_below  ~> cfun_below_iff
   862   below_cfun_ext     ~> cfun_belowI
   863   cont2cont_Rep_CFun ~> cont2cont_APP
   864 
   865 * The Abs and Rep functions for various types have changed names.
   866 Related theorem names have also changed to match. INCOMPATIBILITY.
   867 
   868   Rep_CFun  ~> Rep_cfun
   869   Abs_CFun  ~> Abs_cfun
   870   Rep_Sprod ~> Rep_sprod
   871   Abs_Sprod ~> Abs_sprod
   872   Rep_Ssum  ~> Rep_ssum
   873   Abs_Ssum  ~> Abs_ssum
   874 
   875 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   876 been renamed to *_bottom_iff.  INCOMPATIBILITY.
   877 
   878 * Various changes to bisimulation/coinduction with domain package:
   879 
   880   - Definitions of "bisim" constants no longer mention definedness.
   881   - With mutual recursion, "bisim" predicate is now curried.
   882   - With mutual recursion, each type gets a separate coind theorem.
   883   - Variable names in bisim_def and coinduct rules have changed.
   884 
   885 INCOMPATIBILITY.
   886 
   887 * Case combinators generated by the domain package for type "foo" are
   888 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
   889 
   890 * Several theorems have been renamed to more accurately reflect the
   891 names of constants and types involved.  INCOMPATIBILITY.
   892 
   893   thelub_const    ~> lub_const
   894   lub_const       ~> is_lub_const
   895   thelubI         ~> lub_eqI
   896   is_lub_lub      ~> is_lubD2
   897   lubI            ~> is_lub_lub
   898   unique_lub      ~> is_lub_unique
   899   is_ub_lub       ~> is_lub_rangeD1
   900   lub_bin_chain   ~> is_lub_bin_chain
   901   lub_fun         ~> is_lub_fun
   902   thelub_fun      ~> lub_fun
   903   thelub_cfun     ~> lub_cfun
   904   thelub_Pair     ~> lub_Pair
   905   lub_cprod       ~> is_lub_prod
   906   thelub_cprod    ~> lub_prod
   907   minimal_cprod   ~> minimal_prod
   908   inst_cprod_pcpo ~> inst_prod_pcpo
   909   UU_I            ~> bottomI
   910   compact_UU      ~> compact_bottom
   911   deflation_UU    ~> deflation_bottom
   912   finite_deflation_UU ~> finite_deflation_bottom
   913 
   914 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
   915 
   916   sq_ord_less_eq_trans ~> below_eq_trans
   917   sq_ord_eq_less_trans ~> eq_below_trans
   918   refl_less            ~> below_refl
   919   trans_less           ~> below_trans
   920   antisym_less         ~> below_antisym
   921   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
   922   box_less             ~> box_below
   923   rev_trans_less       ~> rev_below_trans
   924   not_less2not_eq      ~> not_below2not_eq
   925   less_UU_iff          ~> below_UU_iff
   926   flat_less_iff        ~> flat_below_iff
   927   adm_less             ~> adm_below
   928   adm_not_less         ~> adm_not_below
   929   adm_compact_not_less ~> adm_compact_not_below
   930   less_fun_def         ~> below_fun_def
   931   expand_fun_less      ~> fun_below_iff
   932   less_fun_ext         ~> fun_belowI
   933   less_discr_def       ~> below_discr_def
   934   discr_less_eq        ~> discr_below_eq
   935   less_unit_def        ~> below_unit_def
   936   less_cprod_def       ~> below_prod_def
   937   prod_lessI           ~> prod_belowI
   938   Pair_less_iff        ~> Pair_below_iff
   939   fst_less_iff         ~> fst_below_iff
   940   snd_less_iff         ~> snd_below_iff
   941   expand_cfun_less     ~> cfun_below_iff
   942   less_cfun_ext        ~> cfun_belowI
   943   injection_less       ~> injection_below
   944   less_up_def          ~> below_up_def
   945   not_Iup_less         ~> not_Iup_below
   946   Iup_less             ~> Iup_below
   947   up_less              ~> up_below
   948   Def_inject_less_eq   ~> Def_below_Def
   949   Def_less_is_eq       ~> Def_below_iff
   950   spair_less_iff       ~> spair_below_iff
   951   less_sprod           ~> below_sprod
   952   spair_less           ~> spair_below
   953   sfst_less_iff        ~> sfst_below_iff
   954   ssnd_less_iff        ~> ssnd_below_iff
   955   fix_least_less       ~> fix_least_below
   956   dist_less_one        ~> dist_below_one
   957   less_ONE             ~> below_ONE
   958   ONE_less_iff         ~> ONE_below_iff
   959   less_sinlD           ~> below_sinlD
   960   less_sinrD           ~> below_sinrD
   961 
   962 
   963 *** FOL and ZF ***
   964 
   965 * All constant names are now qualified internally and use proper
   966 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
   967 
   968 
   969 *** ML ***
   970 
   971 * Antiquotation @{assert} inlines a function bool -> unit that raises
   972 Fail if the argument is false.  Due to inlining the source position of
   973 failed assertions is included in the error output.
   974 
   975 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
   976 text is in practice always evaluated with a stable theory checkpoint.
   977 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
   978 
   979 * Antiquotation @{theory A} refers to theory A from the ancestry of
   980 the current context, not any accidental theory loader state as before.
   981 Potential INCOMPATIBILITY, subtle change in semantics.
   982 
   983 * Syntax.pretty_priority (default 0) configures the required priority
   984 of pretty-printed output and thus affects insertion of parentheses.
   985 
   986 * Syntax.default_root (default "any") configures the inner syntax
   987 category (nonterminal symbol) for parsing of terms.
   988 
   989 * Former exception Library.UnequalLengths now coincides with
   990 ListPair.UnequalLengths.
   991 
   992 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
   993 main functionality is provided by structure Simplifier.
   994 
   995 * Renamed raw "explode" function to "raw_explode" to emphasize its
   996 meaning.  Note that internally to Isabelle, Symbol.explode is used in
   997 almost all situations.
   998 
   999 * Discontinued obsolete function sys_error and exception SYS_ERROR.
  1000 See implementation manual for further details on exceptions in
  1001 Isabelle/ML.
  1002 
  1003 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
  1004 meaning.
  1005 
  1006 * Renamed structure PureThy to Pure_Thy and moved most of its
  1007 operations to structure Global_Theory, to emphasize that this is
  1008 rarely-used global-only stuff.
  1009 
  1010 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
  1011 instead (or tracing for high-volume output).
  1012 
  1013 * Configuration option show_question_marks only affects regular pretty
  1014 printing of types and terms, not raw Term.string_of_vname.
  1015 
  1016 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
  1017 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
  1018 @{thms} for most purposes.
  1019 
  1020 * ML structure Unsynchronized is never opened, not even in Isar
  1021 interaction mode as before.  Old Unsynchronized.set etc. have been
  1022 discontinued -- use plain := instead.  This should be *rare* anyway,
  1023 since modern tools always work via official context data, notably
  1024 configuration options.
  1025 
  1026 * Parallel and asynchronous execution requires special care concerning
  1027 interrupts.  Structure Exn provides some convenience functions that
  1028 avoid working directly with raw Interrupt.  User code must not absorb
  1029 interrupts -- intermediate handling (for cleanup etc.) needs to be
  1030 followed by re-raising of the original exception.  Another common
  1031 source of mistakes are "handle _" patterns, which make the meaning of
  1032 the program subject to physical effects of the environment.
  1033 
  1034 
  1035 
  1036 New in Isabelle2009-2 (June 2010)
  1037 ---------------------------------
  1038 
  1039 *** General ***
  1040 
  1041 * Authentic syntax for *all* logical entities (type classes, type
  1042 constructors, term constants): provides simple and robust
  1043 correspondence between formal entities and concrete syntax.  Within
  1044 the parse tree / AST representations, "constants" are decorated by
  1045 their category (class, type, const) and spelled out explicitly with
  1046 their full internal name.
  1047 
  1048 Substantial INCOMPATIBILITY concerning low-level syntax declarations
  1049 and translations (translation rules and translation functions in ML).
  1050 Some hints on upgrading:
  1051 
  1052   - Many existing uses of 'syntax' and 'translations' can be replaced
  1053     by more modern 'type_notation', 'notation' and 'abbreviation',
  1054     which are independent of this issue.
  1055 
  1056   - 'translations' require markup within the AST; the term syntax
  1057     provides the following special forms:
  1058 
  1059       CONST c   -- produces syntax version of constant c from context
  1060       XCONST c  -- literally c, checked as constant from context
  1061       c         -- literally c, if declared by 'syntax'
  1062 
  1063     Plain identifiers are treated as AST variables -- occasionally the
  1064     system indicates accidental variables via the error "rhs contains
  1065     extra variables".
  1066 
  1067     Type classes and type constructors are marked according to their
  1068     concrete syntax.  Some old translations rules need to be written
  1069     for the "type" category, using type constructor application
  1070     instead of pseudo-term application of the default category
  1071     "logic".
  1072 
  1073   - 'parse_translation' etc. in ML may use the following
  1074     antiquotations:
  1075 
  1076       @{class_syntax c}   -- type class c within parse tree / AST
  1077       @{term_syntax c}    -- type constructor c within parse tree / AST
  1078       @{const_syntax c}   -- ML version of "CONST c" above
  1079       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
  1080 
  1081   - Literal types within 'typed_print_translations', i.e. those *not*
  1082     represented as pseudo-terms are represented verbatim.  Use @{class
  1083     c} or @{type_name c} here instead of the above syntax
  1084     antiquotations.
  1085 
  1086 Note that old non-authentic syntax was based on unqualified base
  1087 names, so all of the above "constant" names would coincide.  Recall
  1088 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
  1089 diagnose syntax problems.
  1090 
  1091 * Type constructors admit general mixfix syntax, not just infix.
  1092 
  1093 * Concrete syntax may be attached to local entities without a proof
  1094 body, too.  This works via regular mixfix annotations for 'fix',
  1095 'def', 'obtain' etc. or via the explicit 'write' command, which is
  1096 similar to the 'notation' command in theory specifications.
  1097 
  1098 * Discontinued unnamed infix syntax (legacy feature for many years) --
  1099 need to specify constant name and syntax separately.  Internal ML
  1100 datatype constructors have been renamed from InfixName to Infix etc.
  1101 Minor INCOMPATIBILITY.
  1102 
  1103 * Schematic theorem statements need to be explicitly markup as such,
  1104 via commands 'schematic_lemma', 'schematic_theorem',
  1105 'schematic_corollary'.  Thus the relevance of the proof is made
  1106 syntactically clear, which impacts performance in a parallel or
  1107 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  1108 
  1109 * Use of cumulative prems via "!" in some proof methods has been
  1110 discontinued (old legacy feature).
  1111 
  1112 * References 'trace_simp' and 'debug_simp' have been replaced by
  1113 configuration options stored in the context. Enabling tracing (the
  1114 case of debugging is similar) in proofs works via
  1115 
  1116   using [[trace_simp = true]]
  1117 
  1118 Tracing is then active for all invocations of the simplifier in
  1119 subsequent goal refinement steps. Tracing may also still be enabled or
  1120 disabled via the ProofGeneral settings menu.
  1121 
  1122 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  1123 'hide_fact' replace the former 'hide' KIND command.  Minor
  1124 INCOMPATIBILITY.
  1125 
  1126 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  1127 more efficient than combinations with -q1 or -q2.
  1128 
  1129 
  1130 *** Pure ***
  1131 
  1132 * Proofterms record type-class reasoning explicitly, using the
  1133 "unconstrain" operation internally.  This eliminates all sort
  1134 constraints from a theorem and proof, introducing explicit
  1135 OFCLASS-premises.  On the proof term level, this operation is
  1136 automatically applied at theorem boundaries, such that closed proofs
  1137 are always free of sort constraints.  INCOMPATIBILITY for tools that
  1138 inspect proof terms.
  1139 
  1140 * Local theory specifications may depend on extra type variables that
  1141 are not present in the result type -- arguments TYPE('a) :: 'a itself
  1142 are added internally.  For example:
  1143 
  1144   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  1145 
  1146 * Predicates of locales introduced by classes carry a mandatory
  1147 "class" prefix.  INCOMPATIBILITY.
  1148 
  1149 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  1150 
  1151 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  1152 'class' instead.
  1153 
  1154 * Command 'code_reflect' allows to incorporate generated ML code into
  1155 runtime environment; replaces immature code_datatype antiquotation.
  1156 INCOMPATIBILITY.
  1157 
  1158 * Code generator: simple concept for abstract datatypes obeying
  1159 invariants.
  1160 
  1161 * Code generator: details of internal data cache have no impact on the
  1162 user space functionality any longer.
  1163 
  1164 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1165 subgoals.  This is more appropriate for interpretations with 'where'.
  1166 INCOMPATIBILITY.
  1167 
  1168 * Command 'example_proof' opens an empty proof body.  This allows to
  1169 experiment with Isar, without producing any persistent result.
  1170 
  1171 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1172 within a local theory context, with explicit checking of the
  1173 constructors involved (in contrast to the raw 'syntax' versions).
  1174 
  1175 * Commands 'types' and 'typedecl' now work within a local theory
  1176 context -- without introducing dependencies on parameters or
  1177 assumptions, which is not possible in Isabelle/Pure.
  1178 
  1179 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1180 within a local theory context.  Minor INCOMPATIBILITY.
  1181 
  1182 
  1183 *** HOL ***
  1184 
  1185 * Command 'typedef' now works within a local theory context -- without
  1186 introducing dependencies on parameters or assumptions, which is not
  1187 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1188 contain multiple interpretations of local typedefs (with different
  1189 non-emptiness proofs), even in a global theory context.
  1190 
  1191 * New package for quotient types.  Commands 'quotient_type' and
  1192 'quotient_definition' may be used for defining types and constants by
  1193 quotient constructions.  An example is the type of integers created by
  1194 quotienting pairs of natural numbers:
  1195 
  1196   fun
  1197     intrel :: "(nat * nat) => (nat * nat) => bool"
  1198   where
  1199     "intrel (x, y) (u, v) = (x + v = u + y)"
  1200 
  1201   quotient_type int = "nat * nat" / intrel
  1202     by (auto simp add: equivp_def expand_fun_eq)
  1203 
  1204   quotient_definition
  1205     "0::int" is "(0::nat, 0::nat)"
  1206 
  1207 The method "lifting" can be used to lift of theorems from the
  1208 underlying "raw" type to the quotient type.  The example
  1209 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1210 construction and provides a reasoning infrastructure for finite sets.
  1211 
  1212 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1213 clash with new theory Quotient in Main HOL.
  1214 
  1215 * Moved the SMT binding into the main HOL session, eliminating
  1216 separate HOL-SMT session.
  1217 
  1218 * List membership infix mem operation is only an input abbreviation.
  1219 INCOMPATIBILITY.
  1220 
  1221 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1222 for future developements; former Library/Word.thy is still present in
  1223 the AFP entry RSAPPS.
  1224 
  1225 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1226 longer shadowed.  INCOMPATIBILITY.
  1227 
  1228 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1229 INCOMPATIBILITY.
  1230 
  1231 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1232 INCOMPATIBILITY.
  1233 
  1234 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1235 instead.  INCOMPATIBILITY.
  1236 
  1237 * Dropped several real-specific versions of lemmas about floor and
  1238 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1239 instead.  INCOMPATIBILITY.
  1240 
  1241   floor_number_of_eq         ~> floor_number_of
  1242   le_floor_eq_number_of      ~> number_of_le_floor
  1243   le_floor_eq_zero           ~> zero_le_floor
  1244   le_floor_eq_one            ~> one_le_floor
  1245   floor_less_eq_number_of    ~> floor_less_number_of
  1246   floor_less_eq_zero         ~> floor_less_zero
  1247   floor_less_eq_one          ~> floor_less_one
  1248   less_floor_eq_number_of    ~> number_of_less_floor
  1249   less_floor_eq_zero         ~> zero_less_floor
  1250   less_floor_eq_one          ~> one_less_floor
  1251   floor_le_eq_number_of      ~> floor_le_number_of
  1252   floor_le_eq_zero           ~> floor_le_zero
  1253   floor_le_eq_one            ~> floor_le_one
  1254   floor_subtract_number_of   ~> floor_diff_number_of
  1255   floor_subtract_one         ~> floor_diff_one
  1256   ceiling_number_of_eq       ~> ceiling_number_of
  1257   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1258   ceiling_le_zero_eq         ~> ceiling_le_zero
  1259   ceiling_le_eq_one          ~> ceiling_le_one
  1260   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1261   less_ceiling_eq_zero       ~> zero_less_ceiling
  1262   less_ceiling_eq_one        ~> one_less_ceiling
  1263   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1264   ceiling_less_eq_zero       ~> ceiling_less_zero
  1265   ceiling_less_eq_one        ~> ceiling_less_one
  1266   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1267   le_ceiling_eq_zero         ~> zero_le_ceiling
  1268   le_ceiling_eq_one          ~> one_le_ceiling
  1269   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1270   ceiling_subtract_one       ~> ceiling_diff_one
  1271 
  1272 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1273 application of the various fold combinators on finite sets.
  1274 
  1275 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1276 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1277 implementation.  INCOMPATIBILTY.
  1278 
  1279 * Theory Library/Coinductive_List has been removed -- superseded by
  1280 AFP/thys/Coinductive.
  1281 
  1282 * Theory PReal, including the type "preal" and related operations, has
  1283 been removed.  INCOMPATIBILITY.
  1284 
  1285 * Real: new development using Cauchy Sequences.
  1286 
  1287 * Split off theory "Big_Operators" containing setsum, setprod,
  1288 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1289 
  1290 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1291 "Int" etc.  INCOMPATIBILITY.
  1292 
  1293 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1294 
  1295 * New set of rules "ac_simps" provides combined assoc / commute
  1296 rewrites for all interpretations of the appropriate generic locales.
  1297 
  1298 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1299 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1300 appropriate and more consistent names suitable for name prefixes
  1301 within the HOL theories.  INCOMPATIBILITY.
  1302 
  1303 * Some generic constants have been put to appropriate theories:
  1304   - less_eq, less: Orderings
  1305   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1306   - inverse, divide: Rings
  1307 INCOMPATIBILITY.
  1308 
  1309 * More consistent naming of type classes involving orderings (and
  1310 lattices):
  1311 
  1312     lower_semilattice                   ~> semilattice_inf
  1313     upper_semilattice                   ~> semilattice_sup
  1314 
  1315     dense_linear_order                  ~> dense_linorder
  1316 
  1317     pordered_ab_group_add               ~> ordered_ab_group_add
  1318     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1319     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1320     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1321     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1322     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1323     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1324     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1325     pordered_comm_ring                  ~> ordered_comm_ring
  1326     pordered_comm_semiring              ~> ordered_comm_semiring
  1327     pordered_ring                       ~> ordered_ring
  1328     pordered_ring_abs                   ~> ordered_ring_abs
  1329     pordered_semiring                   ~> ordered_semiring
  1330 
  1331     ordered_ab_group_add                ~> linordered_ab_group_add
  1332     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1333     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1334     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1335     ordered_field                       ~> linordered_field
  1336     ordered_field_no_lb                 ~> linordered_field_no_lb
  1337     ordered_field_no_ub                 ~> linordered_field_no_ub
  1338     ordered_field_dense_linear_order    ~> dense_linordered_field
  1339     ordered_idom                        ~> linordered_idom
  1340     ordered_ring                        ~> linordered_ring
  1341     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1342     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1343     ordered_ring_strict                 ~> linordered_ring_strict
  1344     ordered_semidom                     ~> linordered_semidom
  1345     ordered_semiring                    ~> linordered_semiring
  1346     ordered_semiring_1                  ~> linordered_semiring_1
  1347     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1348     ordered_semiring_strict             ~> linordered_semiring_strict
  1349 
  1350   The following slightly odd type classes have been moved to a
  1351   separate theory Library/Lattice_Algebras:
  1352 
  1353     lordered_ab_group_add               ~> lattice_ab_group_add
  1354     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1355     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1356     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1357     lordered_ring                       ~> lattice_ring
  1358 
  1359 INCOMPATIBILITY.
  1360 
  1361 * Refined field classes:
  1362   - classes division_ring_inverse_zero, field_inverse_zero,
  1363     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1364     subsumes former division_by_zero class;
  1365   - numerous lemmas have been ported from field to division_ring.
  1366 INCOMPATIBILITY.
  1367 
  1368 * Refined algebra theorem collections:
  1369   - dropped theorem group group_simps, use algebra_simps instead;
  1370   - dropped theorem group ring_simps, use field_simps instead;
  1371   - proper theorem collection field_simps subsumes former theorem
  1372     groups field_eq_simps and field_simps;
  1373   - dropped lemma eq_minus_self_iff which is a duplicate for
  1374     equal_neg_zero.
  1375 INCOMPATIBILITY.
  1376 
  1377 * Theory Finite_Set and List: some lemmas have been generalized from
  1378 sets to lattices:
  1379 
  1380   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1381   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1382   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1383   union_Union_fold_union        ~> sup_Sup_fold_sup
  1384   Inter_fold_inter              ~> Inf_fold_inf
  1385   Union_fold_union              ~> Sup_fold_sup
  1386   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1387   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1388   INTER_fold_inter              ~> INFI_fold_inf
  1389   UNION_fold_union              ~> SUPR_fold_sup
  1390 
  1391 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1392 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1393 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1394 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1395 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1396 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1397 
  1398 * Reorganized theory Multiset: swapped notation of pointwise and
  1399 multiset order:
  1400 
  1401   - pointwise ordering is instance of class order with standard syntax
  1402     <= and <;
  1403   - multiset ordering has syntax <=# and <#; partial order properties
  1404     are provided by means of interpretation with prefix
  1405     multiset_order;
  1406   - less duplication, less historical organization of sections,
  1407     conversion from associations lists to multisets, rudimentary code
  1408     generation;
  1409   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1410     if needed.
  1411 
  1412 Renamed:
  1413 
  1414   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1415   multi_count_ext  ~>  multiset_ext
  1416   diff_union_inverse2  ~>  diff_union_cancelR
  1417 
  1418 INCOMPATIBILITY.
  1419 
  1420 * Theory Permutation: replaced local "remove" by List.remove1.
  1421 
  1422 * Code generation: ML and OCaml code is decorated with signatures.
  1423 
  1424 * Theory List: added transpose.
  1425 
  1426 * Library/Nat_Bijection.thy is a collection of bijective functions
  1427 between nat and other types, which supersedes the older libraries
  1428 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1429 
  1430   Constants:
  1431   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1432   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1433   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1434   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1435   Countable.pair_encode           ~> prod_encode
  1436   NatIso.prod2nat                 ~> prod_encode
  1437   NatIso.nat2prod                 ~> prod_decode
  1438   NatIso.sum2nat                  ~> sum_encode
  1439   NatIso.nat2sum                  ~> sum_decode
  1440   NatIso.list2nat                 ~> list_encode
  1441   NatIso.nat2list                 ~> list_decode
  1442   NatIso.set2nat                  ~> set_encode
  1443   NatIso.nat2set                  ~> set_decode
  1444 
  1445   Lemmas:
  1446   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1447   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1448   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1449   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1450   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1451   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1452   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1453   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1454   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1455   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1456   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1457   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1458   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1459 
  1460 * Sledgehammer:
  1461   - Renamed ATP commands:
  1462     atp_info     ~> sledgehammer running_atps
  1463     atp_kill     ~> sledgehammer kill_atps
  1464     atp_messages ~> sledgehammer messages
  1465     atp_minimize ~> sledgehammer minimize
  1466     print_atps   ~> sledgehammer available_atps
  1467     INCOMPATIBILITY.
  1468   - Added user's manual ("isabelle doc sledgehammer").
  1469   - Added option syntax and "sledgehammer_params" to customize
  1470     Sledgehammer's behavior.  See the manual for details.
  1471   - Modified the Isar proof reconstruction code so that it produces
  1472     direct proofs rather than proofs by contradiction.  (This feature
  1473     is still experimental.)
  1474   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1475     full-typed mode.
  1476   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1477 
  1478 * Nitpick:
  1479   - Added and implemented "binary_ints" and "bits" options.
  1480   - Added "std" option and implemented support for nonstandard models.
  1481   - Added and implemented "finitize" option to improve the precision
  1482     of infinite datatypes based on a monotonicity analysis.
  1483   - Added support for quotient types.
  1484   - Added support for "specification" and "ax_specification"
  1485     constructs.
  1486   - Added support for local definitions (for "function" and
  1487     "termination" proofs).
  1488   - Added support for term postprocessors.
  1489   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1490   - Improved efficiency of "destroy_constrs" optimization.
  1491   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1492     record getters.
  1493   - Fixed soundness bug related to higher-order constructors.
  1494   - Fixed soundness bug when "full_descrs" is enabled.
  1495   - Improved precision of set constructs.
  1496   - Added "atoms" option.
  1497   - Added cache to speed up repeated Kodkod invocations on the same
  1498     problems.
  1499   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1500     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1501     "SAT4J_Light".  INCOMPATIBILITY.
  1502   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1503     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1504   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1505 
  1506 * Method "induct" now takes instantiations of the form t, where t is not
  1507   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1508   If this is not intended, t has to be enclosed in parentheses.
  1509   By default, the equalities generated by definitional instantiations
  1510   are pre-simplified, which may cause parameters of inductive cases
  1511   to disappear, or may even delete some of the inductive cases.
  1512   Use "induct (no_simp)" instead of "induct" to restore the old
  1513   behaviour. The (no_simp) option is also understood by the "cases"
  1514   and "nominal_induct" methods, which now perform pre-simplification, too.
  1515   INCOMPATIBILITY.
  1516 
  1517 
  1518 *** HOLCF ***
  1519 
  1520 * Variable names in lemmas generated by the domain package have
  1521 changed; the naming scheme is now consistent with the HOL datatype
  1522 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1523 
  1524 * The domain package no longer defines the function "foo_copy" for
  1525 recursive domain "foo".  The reach lemma is now stated directly in
  1526 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1527 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1528 
  1529 * Most definedness lemmas generated by the domain package (previously
  1530 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1531 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1532 Proofs that used definedness lemmas as intro rules may break,
  1533 potential INCOMPATIBILITY.
  1534 
  1535 * Induction and casedist rules generated by the domain package now
  1536 declare proper case_names (one called "bottom", and one named for each
  1537 constructor).  INCOMPATIBILITY.
  1538 
  1539 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1540 rules are generated for each domain, INCOMPATIBILITY.
  1541 
  1542   foo_bar.reach       ~> foo.reach  bar.reach
  1543   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1544 
  1545 * Some lemmas generated by the domain package have been renamed for
  1546 consistency with the datatype package, INCOMPATIBILITY.
  1547 
  1548   foo.ind        ~> foo.induct
  1549   foo.finite_ind ~> foo.finite_induct
  1550   foo.coind      ~> foo.coinduct
  1551   foo.casedist   ~> foo.exhaust
  1552   foo.exhaust    ~> foo.nchotomy
  1553 
  1554 * For consistency with other definition packages, the fixrec package
  1555 now generates qualified theorem names, INCOMPATIBILITY.
  1556 
  1557   foo_simps  ~> foo.simps
  1558   foo_unfold ~> foo.unfold
  1559   foo_induct ~> foo.induct
  1560 
  1561 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1562 method and internal fixrec proofs now use the default simpset instead.
  1563 INCOMPATIBILITY.
  1564 
  1565 * The "contlub" predicate has been removed.  Proof scripts should use
  1566 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1567 
  1568 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1569 
  1570 * The constants cpair, cfst, and csnd have been removed in favor of
  1571 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1572 
  1573 
  1574 *** ML ***
  1575 
  1576 * Antiquotations for basic formal entities:
  1577 
  1578     @{class NAME}         -- type class
  1579     @{class_syntax NAME}  -- syntax representation of the above
  1580 
  1581     @{type_name NAME}     -- logical type
  1582     @{type_abbrev NAME}   -- type abbreviation
  1583     @{nonterminal NAME}   -- type of concrete syntactic category
  1584     @{type_syntax NAME}   -- syntax representation of any of the above
  1585 
  1586     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1587     @{const_abbrev NAME}  -- abbreviated constant
  1588     @{const_syntax NAME}  -- syntax representation of any of the above
  1589 
  1590 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1591 syntax constant (cf. 'syntax' command).
  1592 
  1593 * Antiquotation @{make_string} inlines a function to print arbitrary
  1594 values similar to the ML toplevel.  The result is compiler dependent
  1595 and may fall back on "?" in certain situations.
  1596 
  1597 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1598 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1599 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1600 not work with the asynchronous Isar document model.
  1601 
  1602 * Configuration options now admit dynamic default values, depending on
  1603 the context or even global references.
  1604 
  1605 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1606 uses an efficient external library if available (for Poly/ML).
  1607 
  1608 * Renamed some important ML structures, while keeping the old names
  1609 for some time as aliases within the structure Legacy:
  1610 
  1611   OuterKeyword  ~>  Keyword
  1612   OuterLex      ~>  Token
  1613   OuterParse    ~>  Parse
  1614   OuterSyntax   ~>  Outer_Syntax
  1615   PrintMode     ~>  Print_Mode
  1616   SpecParse     ~>  Parse_Spec
  1617   ThyInfo       ~>  Thy_Info
  1618   ThyLoad       ~>  Thy_Load
  1619   ThyOutput     ~>  Thy_Output
  1620   TypeInfer     ~>  Type_Infer
  1621 
  1622 Note that "open Legacy" simplifies porting of sources, but forgetting
  1623 to remove it again will complicate porting again in the future.
  1624 
  1625 * Most operations that refer to a global context are named
  1626 accordingly, e.g. Simplifier.global_context or
  1627 ProofContext.init_global.  There are some situations where a global
  1628 context actually works, but under normal circumstances one needs to
  1629 pass the proper local context through the code!
  1630 
  1631 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1632 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1633 Pretty.pp argument to merge, which is absent in the standard
  1634 Theory_Data version.
  1635 
  1636 * Sorts.certify_sort and derived "cert" operations for types and terms
  1637 no longer minimize sorts.  Thus certification at the boundary of the
  1638 inference kernel becomes invariant under addition of class relations,
  1639 which is an important monotonicity principle.  Sorts are now minimized
  1640 in the syntax layer only, at the boundary between the end-user and the
  1641 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1642 explicitly in rare situations.
  1643 
  1644 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1645 emphasize that this is in no way a standard operation.
  1646 INCOMPATIBILITY.
  1647 
  1648 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1649 usual for resolution.  Rare INCOMPATIBILITY.
  1650 
  1651 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1652 to emphasize that these only work in a global situation (which is
  1653 quite rare).
  1654 
  1655 * Curried take and drop in library.ML; negative length is interpreted
  1656 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1657 
  1658 * Proof terms: type substitutions on proof constants now use canonical
  1659 order of type variables.  INCOMPATIBILITY for tools working with proof
  1660 terms.
  1661 
  1662 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1663 may no longer carry premises.  User-level specifications are
  1664 transformed accordingly by Thm.add_axiom/add_def.
  1665 
  1666 
  1667 *** System ***
  1668 
  1669 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1670 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1671 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1672 
  1673 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1674 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1675 respectively.
  1676 
  1677 * Old lib/scripts/polyml-platform is superseded by the
  1678 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1679 variant, even on a 64 bit machine.  The following example setting
  1680 prefers 64 bit if available:
  1681 
  1682   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1683 
  1684 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1685 Isabelle/Scala layer for advanced prover interaction and integration.
  1686 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1687 component.
  1688 
  1689 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1690 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1691 similar to the default assignment of the document preparation system
  1692 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1693 provides some operations for direct access to the font without asking
  1694 the user for manual installation.
  1695 
  1696 
  1697 
  1698 New in Isabelle2009-1 (December 2009)
  1699 -------------------------------------
  1700 
  1701 *** General ***
  1702 
  1703 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1704 one backslash should be used, even in ML sources.
  1705 
  1706 
  1707 *** Pure ***
  1708 
  1709 * Locale interpretation propagates mixins along the locale hierarchy.
  1710 The currently only available mixins are the equations used to map
  1711 local definitions to terms of the target domain of an interpretation.
  1712 
  1713 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1714 loc" to print all interpretations of locale "loc" in the theory.
  1715 Interpretations in proofs are not shown.
  1716 
  1717 * Thoroughly revised locales tutorial.  New section on conditional
  1718 interpretation.
  1719 
  1720 * On instantiation of classes, remaining undefined class parameters
  1721 are formally declared.  INCOMPATIBILITY.
  1722 
  1723 
  1724 *** Document preparation ***
  1725 
  1726 * New generalized style concept for printing terms: @{foo (style) ...}
  1727 instead of @{foo_style style ...}  (old form is still retained for
  1728 backward compatibility).  Styles can be also applied for
  1729 antiquotations prop, term_type and typeof.
  1730 
  1731 
  1732 *** HOL ***
  1733 
  1734 * New proof method "smt" for a combination of first-order logic with
  1735 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1736 fixed-size bitvectors; there is also basic support for higher-order
  1737 features (esp. lambda abstractions).  It is an incomplete decision
  1738 procedure based on external SMT solvers using the oracle mechanism;
  1739 for the SMT solver Z3, this method is proof-producing.  Certificates
  1740 are provided to avoid calling the external solvers solely for
  1741 re-checking proofs.  Due to a remote SMT service there is no need for
  1742 installing SMT solvers locally.  See src/HOL/SMT.
  1743 
  1744 * New commands to load and prove verification conditions generated by
  1745 the Boogie program verifier or derived systems (e.g. the Verifying C
  1746 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1747 
  1748 * New counterexample generator tool 'nitpick' based on the Kodkod
  1749 relational model finder.  See src/HOL/Tools/Nitpick and
  1750 src/HOL/Nitpick_Examples.
  1751 
  1752 * New commands 'code_pred' and 'values' to invoke the predicate
  1753 compiler and to enumerate values of inductive predicates.
  1754 
  1755 * A tabled implementation of the reflexive transitive closure.
  1756 
  1757 * New implementation of quickcheck uses generic code generator;
  1758 default generators are provided for all suitable HOL types, records
  1759 and datatypes.  Old quickcheck can be re-activated importing theory
  1760 Library/SML_Quickcheck.
  1761 
  1762 * New testing tool Mirabelle for automated proof tools.  Applies
  1763 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1764 every proof step in a theory.  To be used in batch mode via the
  1765 "mirabelle" utility.
  1766 
  1767 * New proof method "sos" (sum of squares) for nonlinear real
  1768 arithmetic (originally due to John Harison). It requires theory
  1769 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1770 works well in practice on quantifier-free real arithmetic with +, -,
  1771 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1772 inequalities between polynomials.  It makes use of external
  1773 semidefinite programming solvers.  Method "sos" generates a
  1774 certificate that can be pasted into the proof thus avoiding the need
  1775 to call an external tool every time the proof is checked.  See
  1776 src/HOL/Library/Sum_Of_Squares.
  1777 
  1778 * New method "linarith" invokes existing linear arithmetic decision
  1779 procedure only.
  1780 
  1781 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1782 
  1783 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1784 Causes full type information to be output to the ATPs.  This slows
  1785 ATPs down considerably but eliminates a source of unsound "proofs"
  1786 that fail later.
  1787 
  1788 * New method "metisFT": A version of metis that uses full type
  1789 information in order to avoid failures of proof reconstruction.
  1790 
  1791 * New evaluator "approximate" approximates an real valued term using
  1792 the same method as the approximation method.
  1793 
  1794 * Method "approximate" now supports arithmetic expressions as
  1795 boundaries of intervals and implements interval splitting and Taylor
  1796 series expansion.
  1797 
  1798 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1799 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1800 
  1801 * New theory SupInf of the supremum and infimum operators for sets of
  1802 reals.
  1803 
  1804 * New theory Probability, which contains a development of measure
  1805 theory, eventually leading to Lebesgue integration and probability.
  1806 
  1807 * Extended Multivariate Analysis to include derivation and Brouwer's
  1808 fixpoint theorem.
  1809 
  1810 * Reorganization of number theory, INCOMPATIBILITY:
  1811   - new number theory development for nat and int, in theories Divides
  1812     and GCD as well as in new session Number_Theory
  1813   - some constants and facts now suffixed with _nat and _int
  1814     accordingly
  1815   - former session NumberTheory now named Old_Number_Theory, including
  1816     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1817   - moved theory Pocklington from src/HOL/Library to
  1818     src/HOL/Old_Number_Theory
  1819 
  1820 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1821 lcm of finite and infinite sets. It is shown that they form a complete
  1822 lattice.
  1823 
  1824 * Class semiring_div requires superclass no_zero_divisors and proof of
  1825 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1826 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1827 generalized to class semiring_div, subsuming former theorems
  1828 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1829 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1830 INCOMPATIBILITY.
  1831 
  1832 * Refinements to lattice classes and sets:
  1833   - less default intro/elim rules in locale variant, more default
  1834     intro/elim rules in class variant: more uniformity
  1835   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1836     le_inf_iff
  1837   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1838     sup_aci)
  1839   - renamed ACI to inf_sup_aci
  1840   - new class "boolean_algebra"
  1841   - class "complete_lattice" moved to separate theory
  1842     "Complete_Lattice"; corresponding constants (and abbreviations)
  1843     renamed and with authentic syntax:
  1844     Set.Inf ~>    Complete_Lattice.Inf
  1845     Set.Sup ~>    Complete_Lattice.Sup
  1846     Set.INFI ~>   Complete_Lattice.INFI
  1847     Set.SUPR ~>   Complete_Lattice.SUPR
  1848     Set.Inter ~>  Complete_Lattice.Inter
  1849     Set.Union ~>  Complete_Lattice.Union
  1850     Set.INTER ~>  Complete_Lattice.INTER
  1851     Set.UNION ~>  Complete_Lattice.UNION
  1852   - authentic syntax for
  1853     Set.Pow
  1854     Set.image
  1855   - mere abbreviations:
  1856     Set.empty               (for bot)
  1857     Set.UNIV                (for top)
  1858     Set.inter               (for inf, formerly Set.Int)
  1859     Set.union               (for sup, formerly Set.Un)
  1860     Complete_Lattice.Inter  (for Inf)
  1861     Complete_Lattice.Union  (for Sup)
  1862     Complete_Lattice.INTER  (for INFI)
  1863     Complete_Lattice.UNION  (for SUPR)
  1864   - object-logic definitions as far as appropriate
  1865 
  1866 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1867 Un_subset_iff are explicitly deleted as default simp rules; then also
  1868 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1869 deleted to achieve the desired effect.
  1870 
  1871 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1872 rules by default any longer; the same applies to min_max.inf_absorb1
  1873 etc.  INCOMPATIBILITY.
  1874 
  1875 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1876 pred_set_conv by default.  INCOMPATIBILITY.
  1877 
  1878 * Power operations on relations and functions are now one dedicated
  1879 constant "compow" with infix syntax "^^".  Power operation on
  1880 multiplicative monoids retains syntax "^" and is now defined generic
  1881 in class power.  INCOMPATIBILITY.
  1882 
  1883 * Relation composition "R O S" now has a more standard argument order:
  1884 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1885 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1886 break, since the O_assoc rule was not rewritten like this.  Fix using
  1887 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1888 
  1889 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1890 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1891 INCOMPATIBILITY.
  1892 
  1893 * Most rules produced by inductive and datatype package have mandatory
  1894 prefixes.  INCOMPATIBILITY.
  1895 
  1896 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1897 the attribute of the same name.  Each of the theorems in the list
  1898 DERIV_intros assumes composition with an additional function and
  1899 matches a variable to the derivative, which has to be solved by the
  1900 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1901 of most elementary terms.  Former Maclauren.DERIV_tac and
  1902 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1903 INCOMPATIBILITY.
  1904 
  1905 * Code generator attributes follow the usual underscore convention:
  1906     code_unfold     replaces    code unfold
  1907     code_post       replaces    code post
  1908     etc.
  1909   INCOMPATIBILITY.
  1910 
  1911 * Renamed methods:
  1912     sizechange -> size_change
  1913     induct_scheme -> induction_schema
  1914   INCOMPATIBILITY.
  1915 
  1916 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1917 INCOMPATIBILITY, use "undefined" directly.
  1918 
  1919 * Renamed theorems:
  1920     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1921     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1922     Suc_plus1 -> Suc_eq_plus1
  1923     *anti_sym -> *antisym*
  1924     vector_less_eq_def -> vector_le_def
  1925   INCOMPATIBILITY.
  1926 
  1927 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1928 INCOMPATIBILITY.
  1929 
  1930 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1931 INCOMPATIBILITY.
  1932 
  1933 
  1934 *** HOLCF ***
  1935 
  1936 * Theory Representable defines a class "rep" of domains that are
  1937 representable (via an ep-pair) in the universal domain type "udom".
  1938 Instances are provided for all type constructors defined in HOLCF.
  1939 
  1940 * The 'new_domain' command is a purely definitional version of the
  1941 domain package, for representable domains.  Syntax is identical to the
  1942 old domain package.  The 'new_domain' package also supports indirect
  1943 recursion using previously-defined type constructors.  See
  1944 src/HOLCF/ex/New_Domain.thy for examples.
  1945 
  1946 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1947 on the left-hand side of an equation, and then performs
  1948 simplification.  Rewriting is done using rules declared with the
  1949 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1950 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1951 
  1952 * The pattern-match compiler in 'fixrec' can now handle constructors
  1953 with HOL function types.  Pattern-match combinators for the Pair
  1954 constructor are pre-configured.
  1955 
  1956 * The 'fixrec' package now produces better fixed-point induction rules
  1957 for mutually-recursive definitions:  Induction rules have conclusions
  1958 of the form "P foo bar" instead of "P <foo, bar>".
  1959 
  1960 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1961 been renamed to "below".  The name "below" now replaces "less" in many
  1962 theorem names.  (Legacy theorem names using "less" are still supported
  1963 as well.)
  1964 
  1965 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1966 patterns can be used to generate strictness rules, or to make
  1967 functions more strict (much like the bang-patterns supported by the
  1968 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1969 examples.
  1970 
  1971 
  1972 *** ML ***
  1973 
  1974 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1975 errors and run-time exceptions, including detailed source positions.
  1976 
  1977 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1978 identified entries, with some additional information such as source
  1979 position, logical grouping etc.
  1980 
  1981 * Theory and context data is now introduced by the simplified and
  1982 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1983 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1984 copy operation) is still available for some time.
  1985 
  1986 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1987 provides a high-level programming interface to synchronized state
  1988 variables with atomic update.  This works via pure function
  1989 application within a critical section -- its runtime should be as
  1990 short as possible; beware of deadlocks if critical code is nested,
  1991 either directly or indirectly via other synchronized variables!
  1992 
  1993 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1994 wraps raw ML references, explicitly indicating their non-thread-safe
  1995 behaviour.  The Isar toplevel keeps this structure open, to
  1996 accommodate Proof General as well as quick and dirty interactive
  1997 experiments with references.
  1998 
  1999 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  2000 parallel tactical reasoning.
  2001 
  2002 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  2003 are similar to SUBPROOF, but are slightly more flexible: only the
  2004 specified parts of the subgoal are imported into the context, and the
  2005 body tactic may introduce new subgoals and schematic variables.
  2006 
  2007 * Old tactical METAHYPS, which does not observe the proof context, has
  2008 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  2009 or Subgoal.FOCUS etc.
  2010 
  2011 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  2012 functors have their own ML name space there is no point to mark them
  2013 separately.)  Minor INCOMPATIBILITY.
  2014 
  2015 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  2016 
  2017 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  2018 INCOMPATIBILITY.
  2019 
  2020 * Operations of structure Skip_Proof no longer require quick_and_dirty
  2021 mode, which avoids critical setmp.
  2022 
  2023 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  2024 combinators for "args".  INCOMPATIBILITY, need to use simplified
  2025 Attrib/Method.setup introduced in Isabelle2009.
  2026 
  2027 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  2028 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  2029 last resort.  INCOMPATIBILITY.
  2030 
  2031 * Display.pretty_thm now requires a proper context (cf. former
  2032 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  2033 or even Display.pretty_thm_without_context as last resort.
  2034 INCOMPATIBILITY.
  2035 
  2036 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  2037 Syntax.pretty_typ/term directly, preferably with proper context
  2038 instead of global theory.
  2039 
  2040 
  2041 *** System ***
  2042 
  2043 * Further fine tuning of parallel proof checking, scales up to 8 cores
  2044 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  2045 usedir option -q.
  2046 
  2047 * Support for additional "Isabelle components" via etc/components, see
  2048 also the system manual.
  2049 
  2050 * The isabelle makeall tool now operates on all components with
  2051 IsaMakefile, not just hardwired "logics".
  2052 
  2053 * Removed "compress" option from isabelle-process and isabelle usedir;
  2054 this is always enabled.
  2055 
  2056 * Discontinued support for Poly/ML 4.x versions.
  2057 
  2058 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  2059 on a given logic image.  This requires the lighttpd webserver and is
  2060 currently supported on Linux only.
  2061 
  2062 
  2063 
  2064 New in Isabelle2009 (April 2009)
  2065 --------------------------------
  2066 
  2067 *** General ***
  2068 
  2069 * Simplified main Isabelle executables, with less surprises on
  2070 case-insensitive file-systems (such as Mac OS).
  2071 
  2072   - The main Isabelle tool wrapper is now called "isabelle" instead of
  2073     "isatool."
  2074 
  2075   - The former "isabelle" alias for "isabelle-process" has been
  2076     removed (should rarely occur to regular users).
  2077 
  2078   - The former "isabelle-interface" and its alias "Isabelle" have been
  2079     removed (interfaces are now regular Isabelle tools).
  2080 
  2081 Within scripts and make files, the Isabelle environment variables
  2082 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  2083 respectively.  (The latter are still available as legacy feature.)
  2084 
  2085 The old isabelle-interface wrapper could react in confusing ways if
  2086 the interface was uninstalled or changed otherwise.  Individual
  2087 interface tool configuration is now more explicit, see also the
  2088 Isabelle system manual.  In particular, Proof General is now available
  2089 via "isabelle emacs".
  2090 
  2091 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  2092 purge installed copies of Isabelle executables and re-run "isabelle
  2093 install -p ...", or use symlinks.
  2094 
  2095 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  2096 old ~/isabelle, which was slightly non-standard and apt to cause
  2097 surprises on case-insensitive file-systems (such as Mac OS).
  2098 
  2099 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  2100 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  2101 care is required when using older releases of Isabelle.  Note that
  2102 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  2103 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  2104 
  2105 * Proofs of fully specified statements are run in parallel on
  2106 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  2107 a regular 4-core machine, if the initial heap space is made reasonably
  2108 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  2109 
  2110 * The main reference manuals ("isar-ref", "implementation", and
  2111 "system") have been updated and extended.  Formally checked references
  2112 as hyperlinks are now available uniformly.
  2113 
  2114 
  2115 *** Pure ***
  2116 
  2117 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  2118 respects.  The most important changes are listed below.  See the
  2119 Tutorial on Locales ("locales" manual) for details.
  2120 
  2121 - In locale expressions, instantiation replaces renaming.  Parameters
  2122 must be declared in a for clause.  To aid compatibility with previous
  2123 parameter inheritance, in locale declarations, parameters that are not
  2124 'touched' (instantiation position "_" or omitted) are implicitly added
  2125 with their syntax at the beginning of the for clause.
  2126 
  2127 - Syntax from abbreviations and definitions in locales is available in
  2128 locale expressions and context elements.  The latter is particularly
  2129 useful in locale declarations.
  2130 
  2131 - More flexible mechanisms to qualify names generated by locale
  2132 expressions.  Qualifiers (prefixes) may be specified in locale
  2133 expressions, and can be marked as mandatory (syntax: "name!:") or
  2134 optional (syntax "name?:").  The default depends for plain "name:"
  2135 depends on the situation where a locale expression is used: in
  2136 commands 'locale' and 'sublocale' prefixes are optional, in
  2137 'interpretation' and 'interpret' prefixes are mandatory.  The old
  2138 implicit qualifiers derived from the parameter names of a locale are
  2139 no longer generated.
  2140 
  2141 - Command "sublocale l < e" replaces "interpretation l < e".  The
  2142 instantiation clause in "interpretation" and "interpret" (square
  2143 brackets) is no longer available.  Use locale expressions.
  2144 
  2145 - When converting proof scripts, mandatory qualifiers in
  2146 'interpretation' and 'interpret' should be retained by default, even
  2147 if this is an INCOMPATIBILITY compared to former behavior.  In the
  2148 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  2149 in locale expressions range over a single locale instance only.
  2150 
  2151 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  2152 In existing theorem specifications replace the includes element by the
  2153 respective context elements of the included locale, omitting those
  2154 that are already present in the theorem specification.  Multiple
  2155 assume elements of a locale should be replaced by a single one
  2156 involving the locale predicate.  In the proof body, declarations (most
  2157 notably theorems) may be regained by interpreting the respective
  2158 locales in the proof context as required (command "interpret").
  2159 
  2160 If using "includes" in replacement of a target solely because the
  2161 parameter types in the theorem are not as general as in the target,
  2162 consider declaring a new locale with additional type constraints on
  2163 the parameters (context element "constrains").
  2164 
  2165 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2166 
  2167 - Locale interpretation commands no longer attempt to simplify goal.
  2168 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2169 methods intro_locales and unfold_locales to clarify.
  2170 
  2171 - Locale interpretation commands no longer accept interpretation
  2172 attributes.  INCOMPATIBILITY.
  2173 
  2174 * Class declaration: so-called "base sort" must not be given in import
  2175 list any longer, but is inferred from the specification.  Particularly
  2176 in HOL, write
  2177 
  2178     class foo = ...
  2179 
  2180 instead of
  2181 
  2182     class foo = type + ...
  2183 
  2184 * Class target: global versions of theorems stemming do not carry a
  2185 parameter prefix any longer.  INCOMPATIBILITY.
  2186 
  2187 * Class 'instance' command no longer accepts attached definitions.
  2188 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2189 
  2190 * Recovered hiding of consts, which was accidentally broken in
  2191 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2192 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2193 
  2194 * Slightly more coherent Pure syntax, with updated documentation in
  2195 isar-ref manual.  Removed locales meta_term_syntax and
  2196 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2197 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2198 directly in regular applications.
  2199 
  2200 * There is a new syntactic category "float_const" for signed decimal
  2201 fractions (e.g. 123.45 or -123.45).
  2202 
  2203 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2204 interface with 'setup' command instead.
  2205 
  2206 * Command 'local_setup' is similar to 'setup', but operates on a local
  2207 theory context.
  2208 
  2209 * The 'axiomatization' command now only works within a global theory
  2210 context.  INCOMPATIBILITY.
  2211 
  2212 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2213 hypotheses.  Sorts required in the course of reasoning need to be
  2214 covered by the constraints in the initial statement, completed by the
  2215 type instance information of the background theory.  Non-trivial sort
  2216 hypotheses, which rarely occur in practice, may be specified via
  2217 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2218 
  2219   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2220 
  2221 The result contains an implicit sort hypotheses as before --
  2222 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2223 normalization.
  2224 
  2225 * Generalized Isar history, with support for linear undo, direct state
  2226 addressing etc.
  2227 
  2228 * Changed defaults for unify configuration options:
  2229 
  2230   unify_trace_bound = 50 (formerly 25)
  2231   unify_search_bound = 60 (formerly 30)
  2232 
  2233 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2234 
  2235   a) On theory merge, the last set of code equations for a particular
  2236      constant is taken (in accordance with the policy applied by other
  2237      parts of the code generator framework).
  2238 
  2239   b) Code equations stemming from explicit declarations (e.g. code
  2240      attribute) gain priority over default code equations stemming
  2241      from definition, primrec, fun etc.
  2242 
  2243 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2244 
  2245 * Unified theorem tables for both code generators.  Thus [code
  2246 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2247 
  2248 * Command 'find_consts' searches for constants based on type and name
  2249 patterns, e.g.
  2250 
  2251     find_consts "_ => bool"
  2252 
  2253 By default, matching is against subtypes, but it may be restricted to
  2254 the whole type.  Searching by name is possible.  Multiple queries are
  2255 conjunctive and queries may be negated by prefixing them with a
  2256 hyphen:
  2257 
  2258     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2259 
  2260 * New 'find_theorems' criterion "solves" matches theorems that
  2261 directly solve the current goal (modulo higher-order unification).
  2262 
  2263 * Auto solve feature for main theorem statements: whenever a new goal
  2264 is stated, "find_theorems solves" is called; any theorems that could
  2265 solve the lemma directly are listed as part of the goal state.
  2266 Cf. associated options in Proof General Isabelle settings menu,
  2267 enabled by default, with reasonable timeout for pathological cases of
  2268 higher-order unification.
  2269 
  2270 
  2271 *** Document preparation ***
  2272 
  2273 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2274 demanding keyword 'by' and supporting the full method expression
  2275 syntax just like the Isar command 'by'.
  2276 
  2277 
  2278 *** HOL ***
  2279 
  2280 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2281 points Main and Complex_Main remain as before.
  2282 
  2283 * Logic image HOL-Plain provides a minimal HOL with the most important
  2284 tools available (inductive, datatype, primrec, ...).  This facilitates
  2285 experimentation and tool development.  Note that user applications
  2286 (and library theories) should never refer to anything below theory
  2287 Main, as before.
  2288 
  2289 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2290 experimentation due to shorter build times.
  2291 
  2292 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2293 were previously part of former HOL-Complex.  Entry point Hyperreal
  2294 remains valid, but theories formerly using Complex_Main should now use
  2295 new entry point Hypercomplex.
  2296 
  2297 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2298 Posix processes.  Avoids potentially expensive forking of the ML
  2299 process.  New thread-based implementation also works on non-Unix
  2300 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2301 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2302 commands are covered in the isar-ref manual.
  2303 
  2304 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2305 sledgehammer without local ATP installation (Vampire etc.). Other
  2306 provers may be included via suitable ML wrappers, see also
  2307 src/HOL/ATP_Linkup.thy.
  2308 
  2309 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2310 menu.
  2311 
  2312 * The metis method no longer fails because the theorem is too trivial
  2313 (contains the empty clause).
  2314 
  2315 * The metis method now fails in the usual manner, rather than raising
  2316 an exception, if it determines that it cannot prove the theorem.
  2317 
  2318 * Method "coherent" implements a prover for coherent logic (see also
  2319 src/Tools/coherent.ML).
  2320 
  2321 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2322 "undefined" is the right choice to replace "arbitrary", though
  2323 logically there is no difference.  INCOMPATIBILITY.
  2324 
  2325 * Command "value" now integrates different evaluation mechanisms.  The
  2326 result of the first successful evaluation mechanism is printed.  In
  2327 square brackets a particular named evaluation mechanisms may be
  2328 specified (currently, [SML], [code] or [nbe]).  See further
  2329 src/HOL/ex/Eval_Examples.thy.
  2330 
  2331 * Normalization by evaluation now allows non-leftlinear equations.
  2332 Declare with attribute [code nbe].
  2333 
  2334 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2335 as the structured Isar versions "cases" and "induct", cf. the
  2336 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2337 are now presented as a list of individual projections
  2338 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2339 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2340 rare situations a different rule is selected --- notably nested tuple
  2341 elimination instead of former prod.exhaust: use explicit (case_tac t
  2342 rule: prod.exhaust) here.
  2343 
  2344 * Attributes "cases", "induct", "coinduct" support "del" option.
  2345 
  2346 * Removed fact "case_split_thm", which duplicates "case_split".
  2347 
  2348 * The option datatype has been moved to a new theory Option.  Renamed
  2349 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2350 
  2351 * New predicate "strict_mono" classifies strict functions on partial
  2352 orders.  With strict functions on linear orders, reasoning about
  2353 (in)equalities is facilitated by theorems "strict_mono_eq",
  2354 "strict_mono_less_eq" and "strict_mono_less".
  2355 
  2356 * Some set operations are now proper qualified constants with
  2357 authentic syntax.  INCOMPATIBILITY:
  2358 
  2359     op Int ~>   Set.Int
  2360     op Un ~>    Set.Un
  2361     INTER ~>    Set.INTER
  2362     UNION ~>    Set.UNION
  2363     Inter ~>    Set.Inter
  2364     Union ~>    Set.Union
  2365     {} ~>       Set.empty
  2366     UNIV ~>     Set.UNIV
  2367 
  2368 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2369 theory Set.
  2370 
  2371 * Auxiliary class "itself" has disappeared -- classes without any
  2372 parameter are treated as expected by the 'class' command.
  2373 
  2374 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2375 
  2376 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2377 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2378 
  2379 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2380 method "approximation".  It proves formulas on real values by using
  2381 interval arithmetic.  In the formulas are also the transcendental
  2382 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2383 allowed. For examples see
  2384 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2385 
  2386 * Theory "Reflection" now resides in HOL/Library.
  2387 
  2388 * Entry point to Word library now simply named "Word".
  2389 INCOMPATIBILITY.
  2390 
  2391 * Made source layout more coherent with logical distribution
  2392 structure:
  2393 
  2394     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2395     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2396     src/HOL/Library/GCD.thy ~> src/HOL/
  2397     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2398     src/HOL/Library/Parity.thy ~> src/HOL/
  2399     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2400     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2401     src/HOL/Real/Lubs.thy ~> src/HOL/
  2402     src/HOL/Real/PReal.thy ~> src/HOL/
  2403     src/HOL/Real/Rational.thy ~> src/HOL/
  2404     src/HOL/Real/RComplete.thy ~> src/HOL/
  2405     src/HOL/Real/RealDef.thy ~> src/HOL/
  2406     src/HOL/Real/RealPow.thy ~> src/HOL/
  2407     src/HOL/Real/Real.thy ~> src/HOL/
  2408     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2409     src/HOL/Complex/Complex.thy ~> src/HOL/
  2410     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2411     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2412     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2413     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2414     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2415     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2416     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2417     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2418     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2419     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2420     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2421     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2422     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2423     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2424     src/HOL/Real/Float ~> src/HOL/Library/
  2425     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2426     src/HOL/Real/RealVector.thy ~> src/HOL/
  2427 
  2428     src/HOL/arith_data.ML ~> src/HOL/Tools
  2429     src/HOL/hologic.ML ~> src/HOL/Tools
  2430     src/HOL/simpdata.ML ~> src/HOL/Tools
  2431     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2432     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2433     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2434     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2435     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2436     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2437     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2438 
  2439     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2440     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2441     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2442     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2443     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2444     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2445 
  2446 * If methods "eval" and "evaluation" encounter a structured proof
  2447 state with !!/==>, only the conclusion is evaluated to True (if
  2448 possible), avoiding strange error messages.
  2449 
  2450 * Method "sizechange" automates termination proofs using (a
  2451 modification of) the size-change principle.  Requires SAT solver.  See
  2452 src/HOL/ex/Termination.thy for examples.
  2453 
  2454 * Simplifier: simproc for let expressions now unfolds if bound
  2455 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2456 
  2457 * Method "arith": Linear arithmetic now ignores all inequalities when
  2458 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2459 
  2460 * New attribute "arith" for facts that should always be used
  2461 automatically by arithmetic. It is intended to be used locally in
  2462 proofs, e.g.
  2463 
  2464   assumes [arith]: "x > 0"
  2465 
  2466 Global usage is discouraged because of possible performance impact.
  2467 
  2468 * New classes "top" and "bot" with corresponding operations "top" and
  2469 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2470 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2471 
  2472 * Changed definition lemma "less_fun_def" in order to provide an
  2473 instance for preorders on functions; use lemma "less_le" instead.
  2474 INCOMPATIBILITY.
  2475 
  2476 * Theory Orderings: class "wellorder" moved here, with explicit
  2477 induction rule "less_induct" as assumption.  For instantiation of
  2478 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2479 INCOMPATIBILITY.
  2480 
  2481 * Theory Orderings: added class "preorder" as superclass of "order".
  2482 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2483 etc. slightly changed.  Some theorems named order_class.* now named
  2484 preorder_class.*.
  2485 
  2486 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2487 "diag" to "Id_on".
  2488 
  2489 * Theory Finite_Set: added a new fold combinator of type
  2490 
  2491   ('a => 'b => 'b) => 'b => 'a set => 'b
  2492 
  2493 Occasionally this is more convenient than the old fold combinator
  2494 which is now defined in terms of the new one and renamed to
  2495 fold_image.
  2496 
  2497 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2498 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2499 extended with further lemmas!).  At the moment both still exist but
  2500 the former will disappear at some point.
  2501 
  2502 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2503 class recpower.  Type-specific simp rules for various recpower types
  2504 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2505 
  2506 rat_power_0    -> power_0
  2507 rat_power_Suc  -> power_Suc
  2508 realpow_0      -> power_0
  2509 realpow_Suc    -> power_Suc
  2510 complexpow_0   -> power_0
  2511 complexpow_Suc -> power_Suc
  2512 power_poly_0   -> power_0
  2513 power_poly_Suc -> power_Suc
  2514 
  2515 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2516 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2517 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2518 of lemmas from Divides has been generalized from nat to class
  2519 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2520 renames resulting from duplicate elimination:
  2521 
  2522     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2523     zero_dvd_iff ~>         dvd_0_left_iff
  2524     dvd_0 ~>                dvd_0_right
  2525     DIVISION_BY_ZERO_DIV ~> div_by_0
  2526     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2527     mult_div ~>             div_mult_self2_is_id
  2528     mult_mod ~>             mod_mult_self2_is_0
  2529 
  2530 * Theory IntDiv: removed many lemmas that are instances of class-based
  2531 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2532 rename old lemmas as follows:
  2533 
  2534 dvd_diff               -> nat_dvd_diff
  2535 dvd_zminus_iff         -> dvd_minus_iff
  2536 mod_add1_eq            -> mod_add_eq
  2537 mod_mult1_eq           -> mod_mult_right_eq
  2538 mod_mult1_eq'          -> mod_mult_left_eq
  2539 mod_mult_distrib_mod   -> mod_mult_eq
  2540 nat_mod_add_left_eq    -> mod_add_left_eq
  2541 nat_mod_add_right_eq   -> mod_add_right_eq
  2542 nat_mod_div_trivial    -> mod_div_trivial
  2543 nat_mod_mod_trivial    -> mod_mod_trivial
  2544 zdiv_zadd_self1        -> div_add_self1
  2545 zdiv_zadd_self2        -> div_add_self2
  2546 zdiv_zmult_self1       -> div_mult_self2_is_id
  2547 zdiv_zmult_self2       -> div_mult_self1_is_id
  2548 zdvd_triv_left         -> dvd_triv_left
  2549 zdvd_triv_right        -> dvd_triv_right
  2550 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2551 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2552 zmod_zadd_left_eq      -> mod_add_left_eq
  2553 zmod_zadd_right_eq     -> mod_add_right_eq
  2554 zmod_zadd_self1        -> mod_add_self1
  2555 zmod_zadd_self2        -> mod_add_self2
  2556 zmod_zadd1_eq          -> mod_add_eq
  2557 zmod_zdiff1_eq         -> mod_diff_eq
  2558 zmod_zdvd_zmod         -> mod_mod_cancel
  2559 zmod_zmod_cancel       -> mod_mod_cancel
  2560 zmod_zmult_self1       -> mod_mult_self2_is_0
  2561 zmod_zmult_self2       -> mod_mult_self1_is_0
  2562 zmod_1                 -> mod_by_1
  2563 zdiv_1                 -> div_by_1
  2564 zdvd_abs1              -> abs_dvd_iff
  2565 zdvd_abs2              -> dvd_abs_iff
  2566 zdvd_refl              -> dvd_refl
  2567 zdvd_trans             -> dvd_trans
  2568 zdvd_zadd              -> dvd_add
  2569 zdvd_zdiff             -> dvd_diff
  2570 zdvd_zminus_iff        -> dvd_minus_iff
  2571 zdvd_zminus2_iff       -> minus_dvd_iff
  2572 zdvd_zmultD            -> dvd_mult_right
  2573 zdvd_zmultD2           -> dvd_mult_left
  2574 zdvd_zmult_mono        -> mult_dvd_mono
  2575 zdvd_0_right           -> dvd_0_right
  2576 zdvd_0_left            -> dvd_0_left_iff
  2577 zdvd_1_left            -> one_dvd
  2578 zminus_dvd_iff         -> minus_dvd_iff
  2579 
  2580 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2581 
  2582 * The real numbers offer decimal input syntax: 12.34 is translated
  2583 into 1234/10^2. This translation is not reversed upon output.
  2584 
  2585 * Theory Library/Polynomial defines an abstract type 'a poly of
  2586 univariate polynomials with coefficients of type 'a.  In addition to
  2587 the standard ring operations, it also supports div and mod.  Code
  2588 generation is also supported, using list-style constructors.
  2589 
  2590 * Theory Library/Inner_Product defines a class of real_inner for real
  2591 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2592 => real.  Class real_inner is a subclass of real_normed_vector from
  2593 theory RealVector.
  2594 
  2595 * Theory Library/Product_Vector provides instances for the product
  2596 type 'a * 'b of several classes from RealVector and Inner_Product.
  2597 Definitions of addition, subtraction, scalar multiplication, norms,
  2598 and inner products are included.
  2599 
  2600 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2601 addition to the field operations, numerals and case syntax are also
  2602 supported.
  2603 
  2604 * Theory Library/Diagonalize provides constructive version of Cantor's
  2605 first diagonalization argument.
  2606 
  2607 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2608 zlcm (for int); carried together from various gcd/lcm developements in
  2609 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2610 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2611 may recover tupled syntax as follows:
  2612 
  2613     hide (open) const gcd
  2614     abbreviation gcd where
  2615       "gcd == (%(a, b). GCD.gcd a b)"
  2616     notation (output)
  2617       GCD.gcd ("gcd '(_, _')")
  2618 
  2619 The same works for lcm, zgcd, zlcm.
  2620 
  2621 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2622 instantiations for algebraic structures.  Removed some duplicate
  2623 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2624 
  2625 * ML antiquotation @{code} takes a constant as argument and generates
  2626 corresponding code in background and inserts name of the corresponding
  2627 resulting ML value/function/datatype constructor binding in place.
  2628 All occurrences of @{code} with a single ML block are generated
  2629 simultaneously.  Provides a generic and safe interface for
  2630 instrumentalizing code generation.  See
  2631 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2632 In future you ought to refrain from ad-hoc compiling generated SML
  2633 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2634 cannot refer to constants for which user-defined serializations are
  2635 set.  Refer to the corresponding ML counterpart directly in that
  2636 cases.
  2637 
  2638 * Command 'rep_datatype': instead of theorem names the command now
  2639 takes a list of terms denoting the constructors of the type to be
  2640 represented as datatype.  The characteristic theorems have to be
  2641 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2642 have disappeared in favour of existing ones:
  2643 
  2644     unit_induct                 ~> unit.induct
  2645     prod_induct                 ~> prod.induct
  2646     sum_induct                  ~> sum.induct
  2647     Suc_Suc_eq                  ~> nat.inject
  2648     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2649 
  2650 
  2651 *** HOL-Algebra ***
  2652 
  2653 * New locales for orders and lattices where the equivalence relation
  2654 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2655 locales use a record structure with field eq for the equivalence.
  2656 
  2657 * New theory of factorial domains.
  2658 
  2659 * Units_l_inv and Units_r_inv are now simp rules by default.
  2660 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2661 and/or r_inv will now also require deletion of these lemmas.
  2662 
  2663 * Renamed the following theorems, INCOMPATIBILITY:
  2664 
  2665 UpperD ~> Upper_memD
  2666 LowerD ~> Lower_memD
  2667 least_carrier ~> least_closed
  2668 greatest_carrier ~> greatest_closed
  2669 greatest_Lower_above ~> greatest_Lower_below
  2670 one_zero ~> carrier_one_zero
  2671 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2672 
  2673 
  2674 *** HOL-Nominal ***
  2675 
  2676 * Nominal datatypes can now contain type-variables.
  2677 
  2678 * Commands 'nominal_inductive' and 'equivariance' work with local
  2679 theory targets.
  2680 
  2681 * Nominal primrec can now works with local theory targets and its
  2682 specification syntax now conforms to the general format as seen in
  2683 'inductive' etc.
  2684 
  2685 * Method "perm_simp" honours the standard simplifier attributes
  2686 (no_asm), (no_asm_use) etc.
  2687 
  2688 * The new predicate #* is defined like freshness, except that on the
  2689 left hand side can be a set or list of atoms.
  2690 
  2691 * Experimental command 'nominal_inductive2' derives strong induction
  2692 principles for inductive definitions.  In contrast to
  2693 'nominal_inductive', which can only deal with a fixed number of
  2694 binders, it can deal with arbitrary expressions standing for sets of
  2695 atoms to be avoided.  The only inductive definition we have at the
  2696 moment that needs this generalisation is the typing rule for Lets in
  2697 the algorithm W:
  2698 
  2699  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2700  -----------------------------------------------------------------
  2701          Gamma |- Let x be t1 in t2 : T2
  2702 
  2703 In this rule one wants to avoid all the binders that are introduced by
  2704 "close Gamma T1".  We are looking for other examples where this
  2705 feature might be useful.  Please let us know.
  2706 
  2707 
  2708 *** HOLCF ***
  2709 
  2710 * Reimplemented the simplification procedure for proving continuity
  2711 subgoals.  The new simproc is extensible; users can declare additional
  2712 continuity introduction rules with the attribute [cont2cont].
  2713 
  2714 * The continuity simproc now uses a different introduction rule for
  2715 solving continuity subgoals on terms with lambda abstractions.  In
  2716 some rare cases the new simproc may fail to solve subgoals that the
  2717 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2718 Potential INCOMPATIBILITY.
  2719 
  2720 * Command 'fixrec': specification syntax now conforms to the general
  2721 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2722 examples.  INCOMPATIBILITY.
  2723 
  2724 
  2725 *** ZF ***
  2726 
  2727 * Proof of Zorn's Lemma for partial orders.
  2728 
  2729 
  2730 *** ML ***
  2731 
  2732 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2733 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2734 depends on multithreading, so timouts will not work before Poly/ML
  2735 5.2.1!
  2736 
  2737 * High-level support for concurrent ML programming, see
  2738 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2739 particularly convenient to organize independent functional
  2740 computations.  The concept of "synchronized variables" provides a
  2741 higher-order interface for components with shared state, avoiding the
  2742 delicate details of mutexes and condition variables.  (Requires
  2743 Poly/ML 5.2.1 or later.)
  2744 
  2745 * ML bindings produced via Isar commands are stored within the Isar
  2746 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2747 become thread-safe and work with undo as expected (concerning
  2748 top-level bindings, not side-effects on global references).
  2749 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2750 compiler at runtime; really global bindings need to be given outside a
  2751 theory.  (Requires Poly/ML 5.2 or later.)
  2752 
  2753 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2754 context.  Top-level ML bindings are stored within the proof context in
  2755 a purely sequential fashion, disregarding the nested proof structure.
  2756 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2757 proof.  (Requires Poly/ML 5.2 or later.)
  2758 
  2759 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2760 and Method.setup, as well as Isar commands 'attribute_setup' and
  2761 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2762 existing code accordingly, or use plain 'setup' together with old
  2763 Method.add_method.
  2764 
  2765 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2766 to 'a -> thm, while results are always tagged with an authentic oracle
  2767 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2768 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2769 accordingly.  Note that extra performance may be gained by producing
  2770 the cterm carefully, avoiding slow Thm.cterm_of.
  2771 
  2772 * Simplified interface for defining document antiquotations via
  2773 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2774 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2775 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2776 examples.
  2777 
  2778 * More systematic treatment of long names, abstract name bindings, and
  2779 name space operations.  Basic operations on qualified names have been
  2780 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2781 Long_Name.append.  Old type bstring has been mostly replaced by
  2782 abstract type binding (see structure Binding), which supports precise
  2783 qualification by packages and local theory targets, as well as proper
  2784 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2785 bstring values into Binding.name, or better pass through abstract
  2786 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2787 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2788 
  2789 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2790 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2791 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2792 
  2793 * Disposed old type and term read functions (Sign.read_def_typ,
  2794 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2795 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2796 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2797 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2798 resort for legacy applications.
  2799 
  2800 * Disposed old declarations, tactics, tactic combinators that refer to
  2801 the simpset or claset of an implicit theory (such as Addsimps,
  2802 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2803 embedded ML text, or local_simpset_of with a proper context passed as
  2804 explicit runtime argument.
  2805 
  2806 * Rules and tactics that read instantiations (read_instantiate,
  2807 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2808 context, which is required for parsing and type-checking.  Moreover,
  2809 the variables are specified as plain indexnames, not string encodings
  2810 thereof.  INCOMPATIBILITY.
  2811 
  2812 * Generic Toplevel.add_hook interface allows to analyze the result of
  2813 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2814 for theorem dependency output of transactions resulting in a new
  2815 theory state.
  2816 
  2817 * ML antiquotations: block-structured compilation context indicated by
  2818 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2819 
  2820   @{binding name}                         - basic name binding
  2821   @{let ?pat = term}                      - term abbreviation (HO matching)
  2822   @{note name = fact}                     - fact abbreviation
  2823   @{thm fact}                             - singleton fact (with attributes)
  2824   @{thms fact}                            - general fact (with attributes)
  2825   @{lemma prop by method}                 - singleton goal
  2826   @{lemma prop by meth1 meth2}            - singleton goal
  2827   @{lemma prop1 ... propN by method}      - general goal
  2828   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2829   @{lemma (open) ...}                     - open derivation
  2830 
  2831 
  2832 *** System ***
  2833 
  2834 * The Isabelle "emacs" tool provides a specific interface to invoke
  2835 Proof General / Emacs, with more explicit failure if that is not
  2836 installed (the old isabelle-interface script silently falls back on
  2837 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2838 installation location of the Proof General distribution.
  2839 
  2840 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2841 the Isabelle process into a JVM/Scala application.  See
  2842 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2843 process wrapper has been discontinued.)
  2844 
  2845 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2846 
  2847 * Various status messages (with exact source position information) are
  2848 emitted, if proper markup print mode is enabled.  This allows
  2849 user-interface components to provide detailed feedback on internal
  2850 prover operations.
  2851 
  2852 
  2853 
  2854 New in Isabelle2008 (June 2008)
  2855 -------------------------------
  2856 
  2857 *** General ***
  2858 
  2859 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2860 and updated, with formally checked references as hyperlinks.
  2861 
  2862 * Theory loader: use_thy (and similar operations) no longer set the
  2863 implicit ML context, which was occasionally hard to predict and in
  2864 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2865 provides a proper context already.
  2866 
  2867 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2868 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2869 'use' within a theory file will do the job.
  2870 
  2871 * Name space merge now observes canonical order, i.e. the second space
  2872 is inserted into the first one, while existing entries in the first
  2873 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2874 swap theory imports.
  2875 
  2876 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2877 INCOMPATIBILITY in identifier syntax etc.
  2878 
  2879 * Outer syntax: string tokens no longer admit escaped white space,
  2880 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2881 white space without escapes.
  2882 
  2883 * Outer syntax: string tokens may contain arbitrary character codes
  2884 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2885 "foo_bar".
  2886 
  2887 
  2888 *** Pure ***
  2889 
  2890 * Context-dependent token translations.  Default setup reverts locally
  2891 fixed variables, and adds hilite markup for undeclared frees.
  2892 
  2893 * Unused theorems can be found using the new command 'unused_thms'.
  2894 There are three ways of invoking it:
  2895 
  2896 (1) unused_thms
  2897      Only finds unused theorems in the current theory.
  2898 
  2899 (2) unused_thms thy_1 ... thy_n -
  2900      Finds unused theorems in the current theory and all of its ancestors,
  2901      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2902 
  2903 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2904      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2905      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2906      their ancestors.
  2907 
  2908 In order to increase the readability of the list produced by
  2909 unused_thms, theorems that have been created by a particular instance
  2910 of a theory command such as 'inductive' or 'function' are considered
  2911 to belong to the same "group", meaning that if at least one theorem in
  2912 this group is used, the other theorems in the same group are no longer
  2913 reported as unused.  Moreover, if all theorems in the group are
  2914 unused, only one theorem in the group is displayed.
  2915 
  2916 Note that proof objects have to be switched on in order for
  2917 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2918 usually the case when using Proof General with the default settings).
  2919 
  2920 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2921 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2922 duplicate fact bindings, or even accidental fact duplications.  Note
  2923 that tools may maintain dynamically scoped facts systematically, using
  2924 PureThy.add_thms_dynamic.
  2925 
  2926 * Command 'hide' now allows to hide from "fact" name space as well.
  2927 
  2928 * Eliminated destructive theorem database, simpset, claset, and
  2929 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2930 update of theories within ML code.
  2931 
  2932 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2933 INCOMPATIBILITY, object-logics depending on former Pure require
  2934 additional setup PureThy.old_appl_syntax_setup; object-logics
  2935 depending on former CPure need to refer to Pure.
  2936 
  2937 * Commands 'use' and 'ML' are now purely functional, operating on
  2938 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2939 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2940 INCOMPATIBILITY.
  2941 
  2942 * Command 'setup': discontinued implicit version with ML reference.
  2943 
  2944 * Instantiation target allows for simultaneous specification of class
  2945 instance operations together with an instantiation proof.
  2946 Type-checking phase allows to refer to class operations uniformly.
  2947 See src/HOL/Complex/Complex.thy for an Isar example and
  2948 src/HOL/Library/Eval.thy for an ML example.
  2949 
  2950 * Indexing of literal facts: be more serious about including only
  2951 facts from the visible specification/proof context, but not the
  2952 background context (locale etc.).  Affects `prop` notation and method
  2953 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2954 situations.
  2955 
  2956 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2957 "(open)" option, which used to expose internal bound variables to the
  2958 proof text.
  2959 
  2960 * Isar statements: removed obsolete case "rule_context".
  2961 INCOMPATIBILITY, better use explicit fixes/assumes.
  2962 
  2963 * Locale proofs: default proof step now includes 'unfold_locales';
  2964 hence 'proof' without argument may be used to unfold locale
  2965 predicates.
  2966 
  2967 
  2968 *** Document preparation ***
  2969 
  2970 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2971 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2972 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2973 spot); renamed link color from "darkblue" to "linkcolor" (default
  2974 value unchanged, can be redefined via \definecolor); no longer sets
  2975 "a4paper" option (unnecessary or even intrusive).
  2976 
  2977 * Antiquotation @{lemma A method} proves proposition A by the given
  2978 method (either a method name or a method name plus (optional) method
  2979 arguments in parentheses) and prints A just like @{prop A}.
  2980 
  2981 
  2982 *** HOL ***
  2983 
  2984 * New primrec package.  Specification syntax conforms in style to
  2985 definition/function/....  No separate induction rule is provided.  The
  2986 "primrec" command distinguishes old-style and new-style specifications
  2987 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2988 When adjusting theories, beware: constants stemming from new-style
  2989 primrec specifications have authentic syntax.
  2990 
  2991 * Metis prover is now an order of magnitude faster, and also works
  2992 with multithreading.
  2993 
  2994 * Metis: the maximum number of clauses that can be produced from a
  2995 theorem is now given by the attribute max_clauses.  Theorems that
  2996 exceed this number are ignored, with a warning printed.
  2997 
  2998 * Sledgehammer no longer produces structured proofs by default. To
  2999 enable, declare [[sledgehammer_full = true]].  Attributes
  3000 reconstruction_modulus, reconstruction_sorts renamed
  3001 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  3002 
  3003 * Method "induct_scheme" derives user-specified induction rules
  3004 from well-founded induction and completeness of patterns. This factors
  3005 out some operations that are done internally by the function package
  3006 and makes them available separately.  See
  3007 src/HOL/ex/Induction_Scheme.thy for examples.
  3008 
  3009 * More flexible generation of measure functions for termination
  3010 proofs: Measure functions can be declared by proving a rule of the
  3011 form "is_measure f" and giving it the [measure_function] attribute.
  3012 The "is_measure" predicate is logically meaningless (always true), and
  3013 just guides the heuristic.  To find suitable measure functions, the
  3014 termination prover sets up the goal "is_measure ?f" of the appropriate
  3015 type and generates all solutions by prolog-style backwards proof using
  3016 the declared rules.
  3017 
  3018 This setup also deals with rules like 
  3019 
  3020   "is_measure f ==> is_measure (list_size f)"
  3021 
  3022 which accommodates nested datatypes that recurse through lists.
  3023 Similar rules are predeclared for products and option types.
  3024 
  3025 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  3026 
  3027   INCOMPATIBILITIES:
  3028 
  3029   - Definitions of overloaded constants on sets have to be replaced by
  3030     definitions on => and bool.
  3031 
  3032   - Some definitions of overloaded operators on sets can now be proved
  3033     using the definitions of the operators on => and bool.  Therefore,
  3034     the following theorems have been renamed:
  3035 
  3036       subset_def   -> subset_eq
  3037       psubset_def  -> psubset_eq
  3038       set_diff_def -> set_diff_eq
  3039       Compl_def    -> Compl_eq
  3040       Sup_set_def  -> Sup_set_eq
  3041       Inf_set_def  -> Inf_set_eq
  3042       sup_set_def  -> sup_set_eq
  3043       inf_set_def  -> inf_set_eq
  3044 
  3045   - Due to the incompleteness of the HO unification algorithm, some
  3046     rules such as subst may require manual instantiation, if some of
  3047     the unknowns in the rule is a set.
  3048 
  3049   - Higher order unification and forward proofs:
  3050     The proof pattern
  3051 
  3052       have "P (S::'a set)" <...>
  3053       then have "EX S. P S" ..
  3054 
  3055     no longer works (due to the incompleteness of the HO unification
  3056     algorithm) and must be replaced by the pattern
  3057 
  3058       have "EX S. P S"
  3059       proof
  3060         show "P S" <...>
  3061       qed
  3062 
  3063   - Calculational reasoning with subst (or similar rules):
  3064     The proof pattern
  3065 
  3066       have "P (S::'a set)" <...>
  3067       also have "S = T" <...>
  3068       finally have "P T" .
  3069 
  3070     no longer works (for similar reasons as the previous example) and
  3071     must be replaced by something like
  3072 
  3073       have "P (S::'a set)" <...>
  3074       moreover have "S = T" <...>
  3075       ultimately have "P T" by simp
  3076 
  3077   - Tactics or packages written in ML code:
  3078     Code performing pattern matching on types via
  3079 
  3080       Type ("set", [T]) => ...
  3081 
  3082     must be rewritten. Moreover, functions like strip_type or
  3083     binder_types no longer return the right value when applied to a
  3084     type of the form
  3085 
  3086       T1 => ... => Tn => U => bool
  3087 
  3088     rather than
  3089 
  3090       T1 => ... => Tn => U set
  3091 
  3092 * Merged theories Wellfounded_Recursion, Accessible_Part and
  3093 Wellfounded_Relations to theory Wellfounded.
  3094 
  3095 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  3096 
  3097 * Class finite no longer treats UNIV as class parameter.  Use class
  3098 enum from theory Library/Enum instead to achieve a similar effect.
  3099 INCOMPATIBILITY.
  3100 
  3101 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  3102 and "Cons".  INCOMPATIBILITY.
  3103 
  3104 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  3105 Potential INCOMPATIBILITY.
  3106 
  3107 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  3108 injective_fst_snd removed, use split_eta and prod_eqI instead.
  3109 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  3110 
  3111 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  3112 the same name in theory Orderings:
  3113 
  3114   less_trans
  3115   less_linear
  3116   le_imp_less_or_eq
  3117   le_less_trans
  3118   less_le_trans
  3119   less_not_sym
  3120   less_asym
  3121 
  3122 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  3123 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  3124 and different variable names.
  3125 
  3126 * Library/Option_ord.thy: Canonical order on option type.
  3127 
  3128 * Library/RBT.thy: Red-black trees, an efficient implementation of
  3129 finite maps.
  3130 
  3131 * Library/Countable.thy: Type class for countable types.
  3132 
  3133 * Theory Int: The representation of numerals has changed.  The infix
  3134 operator BIT and the bit datatype with constructors B0 and B1 have
  3135 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  3136 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  3137 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  3138 accordingly.
  3139 
  3140 * Theory Nat: definition of <= and < on natural numbers no longer
  3141 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  3142 le_def and less_def have disappeared.  Consider lemmas not_less
  3143 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  3144 
  3145 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  3146 (whose purpose mainly is for various fold_set functionals) have been
  3147 abandoned in favor of the existing algebraic classes
  3148 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  3149 lower_semilattice (resp. upper_semilattice) and linorder.
  3150 INCOMPATIBILITY.
  3151 
  3152 * Theory Transitive_Closure: induct and cases rules now declare proper
  3153 case_names ("base" and "step").  INCOMPATIBILITY.
  3154 
  3155 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  3156 lattices.  The form set-specific version is available as
  3157 Inductive.lfp_ordinal_induct_set.
  3158 
  3159 * Renamed theorems "power.simps" to "power_int.simps".
  3160 INCOMPATIBILITY.
  3161 
  3162 * Class semiring_div provides basic abstract properties of semirings
  3163 with division and modulo operations.  Subsumes former class dvd_mod.
  3164 
  3165 * Merged theories IntDef, Numeral and IntArith into unified theory
  3166 Int.  INCOMPATIBILITY.
  3167 
  3168 * Theory Library/Code_Index: type "index" now represents natural
  3169 numbers rather than integers.  INCOMPATIBILITY.
  3170 
  3171 * New class "uminus" with operation "uminus" (split of from class
  3172 "minus" which now only has operation "minus", binary).
  3173 INCOMPATIBILITY.
  3174 
  3175 * Constants "card", "internal_split", "option_map" now with authentic
  3176 syntax.  INCOMPATIBILITY.
  3177 
  3178 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3179 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3180 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3181 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3182 Sup_set_def, le_def, less_def, option_map_def now with object
  3183 equality.  INCOMPATIBILITY.
  3184 
  3185 * Records. Removed K_record, and replaced it by pure lambda term
  3186 %x. c. The simplifier setup is now more robust against eta expansion.
  3187 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3188 
  3189 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3190 
  3191 * Library/ListVector: new theory of arithmetic vector operations.
  3192 
  3193 * Library/Order_Relation: new theory of various orderings as sets of
  3194 pairs.  Defines preorders, partial orders, linear orders and
  3195 well-orders on sets and on types.
  3196 
  3197 
  3198 *** ZF ***
  3199 
  3200 * Renamed some theories to allow to loading both ZF and HOL in the
  3201 same session:
  3202 
  3203   Datatype  -> Datatype_ZF
  3204   Inductive -> Inductive_ZF
  3205   Int       -> Int_ZF
  3206   IntDiv    -> IntDiv_ZF
  3207   Nat       -> Nat_ZF
  3208   List      -> List_ZF
  3209   Main      -> Main_ZF
  3210 
  3211 INCOMPATIBILITY: ZF theories that import individual theories below
  3212 Main might need to be adapted.  Regular theory Main is still
  3213 available, as trivial extension of Main_ZF.
  3214 
  3215 
  3216 *** ML ***
  3217 
  3218 * ML within Isar: antiquotation @{const name} or @{const
  3219 name(typargs)} produces statically-checked Const term.
  3220 
  3221 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3222 (of the same name).  Removed obsolete print command.
  3223 
  3224 * Removed obsolete "use_legacy_bindings" function.
  3225 
  3226 * The ``print mode'' is now a thread-local value derived from a global
  3227 template (the former print_mode reference), thus access becomes
  3228 non-critical.  The global print_mode reference is for session
  3229 management only; user-code should use print_mode_value,
  3230 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3231 
  3232 * Functions system/system_out provide a robust way to invoke external
  3233 shell commands, with propagation of interrupts (requires Poly/ML
  3234 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3235 
  3236 
  3237 *** System ***
  3238 
  3239 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3240 in accordance with Proof General 3.7, which prefers GNU emacs.
  3241 
  3242 * isatool tty runs Isabelle process with plain tty interaction;
  3243 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3244 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3245 
  3246 * isatool browser now works with Cygwin as well, using general
  3247 "javapath" function defined in Isabelle process environment.
  3248 
  3249 * YXML notation provides a simple and efficient alternative to
  3250 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3251 isatool yxml as described in the Isabelle system manual.
  3252 
  3253 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3254 provides general wrapper for managing an Isabelle process in a robust
  3255 fashion, with ``cooked'' output from stdin/stderr.
  3256 
  3257 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3258 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3259 
  3260 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3261 way of changing the user's settings is via
  3262 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3263 script.
  3264 
  3265 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3266 cores of the underlying machine, which is a good starting point for
  3267 optimal performance tuning.  The corresponding usedir option -M allows
  3268 "max" as an alias for "0".  WARNING: does not work on certain versions
  3269 of Mac OS (with Poly/ML 5.1).
  3270 
  3271 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3272 adverse effect of Isabelle flooding interactive front-ends (notably
  3273 ProofGeneral / XEmacs).
  3274 
  3275 
  3276 
  3277 New in Isabelle2007 (November 2007)
  3278 -----------------------------------
  3279 
  3280 *** General ***
  3281 
  3282 * More uniform information about legacy features, notably a
  3283 warning/error of "Legacy feature: ...", depending on the state of the
  3284 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3285 legacy features will disappear eventually.
  3286 
  3287 * Theory syntax: the header format ``theory A = B + C:'' has been
  3288 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3289 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3290 
  3291 * Theory syntax: the old non-Isar theory file format has been
  3292 discontinued altogether.  Note that ML proof scripts may still be used
  3293 with Isar theories; migration is usually quite simple with the ML
  3294 function use_legacy_bindings.  INCOMPATIBILITY.
  3295 
  3296 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3297 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3298 quotes.
  3299 
  3300 * Theory loader: be more serious about observing the static theory
  3301 header specifications (including optional directories), but not the
  3302 accidental file locations of previously successful loads.  The strict
  3303 update policy of former update_thy is now already performed by
  3304 use_thy, so the former has been removed; use_thys updates several
  3305 theories simultaneously, just as 'imports' within a theory header
  3306 specification, but without merging the results.  Potential
  3307 INCOMPATIBILITY: may need to refine theory headers and commands
  3308 ROOT.ML which depend on load order.
  3309 
  3310 * Theory loader: optional support for content-based file
  3311 identification, instead of the traditional scheme of full physical
  3312 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3313 (cf. the system manual).  The new scheme allows to work with
  3314 non-finished theories in persistent session images, such that source
  3315 files may be moved later on without requiring reloads.
  3316 
  3317 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3318 file (with the same base name as the theory) are considered a legacy
  3319 feature, which will disappear eventually. Even now, the theory loader
  3320 no longer maintains dependencies on such files.
  3321 
  3322 * Syntax: the scope for resolving ambiguities via type-inference is
  3323 now limited to individual terms, instead of whole simultaneous
  3324 specifications as before. This greatly reduces the complexity of the
  3325 syntax module and improves flexibility by separating parsing and
  3326 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3327 'fixes' etc.) are required in rare situations.
  3328 
  3329 * Syntax: constants introduced by new-style packages ('definition',
  3330 'abbreviation' etc.) are passed through the syntax module in
  3331 ``authentic mode''. This means that associated mixfix annotations
  3332 really stick to such constants, independently of potential name space
  3333 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3334 trees are represented slightly differently, may need to adapt syntax
  3335 translations accordingly. Use CONST marker in 'translations' and
  3336 @{const_syntax} antiquotation in 'parse_translation' etc.
  3337 
  3338 * Legacy goal package: reduced interface to the bare minimum required
  3339 to keep existing proof scripts running.  Most other user-level
  3340 functions are now part of the OldGoals structure, which is *not* open
  3341 by default (consider isatool expandshort before open OldGoals).
  3342 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3343 these tend to cause confusion about the actual goal (!) context being
  3344 used here, which is not necessarily the same as the_context().
  3345 
  3346 * Command 'find_theorems': supports "*" wild-card in "name:"
  3347 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3348 support a specific search form (see ProofGeneral/CHANGES).
  3349 
  3350 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3351 by default, which means that "prems" (and also "fixed variables") are
  3352 suppressed from proof state output.  Note that the ProofGeneral
  3353 settings mechanism allows to change and save options persistently, but
  3354 older versions of Isabelle will fail to start up if a negative prems
  3355 limit is imposed.
  3356 
  3357 * Local theory targets may be specified by non-nested blocks of
  3358 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3359 contain definitions, theorems etc., including any derived mechanism
  3360 that has been implemented on top of these primitives.  This concept
  3361 generalizes the existing ``theorem (in ...)'' towards more versatility
  3362 and scalability.
  3363 
  3364 * Proof General interface: proper undo of final 'end' command;
  3365 discontinued Isabelle/classic mode (ML proof scripts).
  3366 
  3367 
  3368 *** Document preparation ***
  3369 
  3370 * Added antiquotation @{theory name} which prints the given name,
  3371 after checking that it refers to a valid ancestor theory in the
  3372 current context.
  3373 
  3374 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3375 check the given source text as ML type/structure, printing verbatim.
  3376 
  3377 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3378 "c args == rhs" given in the current context.  (Any number of
  3379 arguments may be given on the LHS.)
  3380 
  3381 
  3382 *** Pure ***
  3383 
  3384 * The 'class' package offers a combination of axclass and locale to
  3385 achieve Haskell-like type classes in Isabelle.  Definitions and
  3386 theorems within a class context produce both relative results (with
  3387 implicit parameters according to the locale context), and polymorphic
  3388 constants with qualified polymorphism (according to the class
  3389 context).  Within the body context of a 'class' target, a separate
  3390 syntax layer ("user space type system") takes care of converting
  3391 between global polymorphic consts and internal locale representation.
  3392 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3393 "isatool doc classes" provides a tutorial.
  3394 
  3395 * Generic code generator framework allows to generate executable
  3396 code for ML and Haskell (including Isabelle classes).  A short usage
  3397 sketch:
  3398 
  3399     internal compilation:
  3400         export_code <list of constants (term syntax)> in SML
  3401     writing SML code to a file:
  3402         export_code <list of constants (term syntax)> in SML <filename>
  3403     writing OCaml code to a file:
  3404         export_code <list of constants (term syntax)> in OCaml <filename>
  3405     writing Haskell code to a bunch of files:
  3406         export_code <list of constants (term syntax)> in Haskell <filename>
  3407 
  3408     evaluating closed propositions to True/False using code generation:
  3409         method ``eval''
  3410 
  3411 Reasonable default setup of framework in HOL.
  3412 
  3413 Theorem attributs for selecting and transforming function equations theorems:
  3414 
  3415     [code fun]:        select a theorem as function equation for a specific constant
  3416     [code fun del]:    deselect a theorem as function equation for a specific constant
  3417     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3418     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3419 
  3420 User-defined serializations (target in {SML, OCaml, Haskell}):
  3421 
  3422     code_const <and-list of constants (term syntax)>
  3423       {(target) <and-list of const target syntax>}+
  3424 
  3425     code_type <and-list of type constructors>
  3426       {(target) <and-list of type target syntax>}+
  3427 
  3428     code_instance <and-list of instances>
  3429       {(target)}+
  3430         where instance ::= <type constructor> :: <class>
  3431 
  3432     code_class <and_list of classes>
  3433       {(target) <and-list of class target syntax>}+
  3434         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3435 
  3436 code_instance and code_class only are effective to target Haskell.
  3437 
  3438 For example usage see src/HOL/ex/Codegenerator.thy and
  3439 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3440 generation from Isabelle/HOL theories is available via "isatool doc
  3441 codegen".
  3442 
  3443 * Code generator: consts in 'consts_code' Isar commands are now
  3444 referred to by usual term syntax (including optional type
  3445 annotations).
  3446 
  3447 * Command 'no_translations' removes translation rules from theory
  3448 syntax.
  3449 
  3450 * Overloaded definitions are now actually checked for acyclic
  3451 dependencies.  The overloading scheme is slightly more general than
  3452 that of Haskell98, although Isabelle does not demand an exact
  3453 correspondence to type class and instance declarations.
  3454 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3455 exotic versions of overloading -- at the discretion of the user!
  3456 
  3457 Polymorphic constants are represented via type arguments, i.e. the
  3458 instantiation that matches an instance against the most general
  3459 declaration given in the signature.  For example, with the declaration
  3460 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3461 as c(nat).  Overloading is essentially simultaneous structural
  3462 recursion over such type arguments.  Incomplete specification patterns
  3463 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3464 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3465 Command 'print_theory' outputs the normalized system of recursive
  3466 equations, see section "definitions".
  3467 
  3468 * Configuration options are maintained within the theory or proof
  3469 context (with name and type bool/int/string), providing a very simple
  3470 interface to a poor-man's version of general context data.  Tools may
  3471 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3472 these values using Config.get etc.  Users may change options via an
  3473 associated attribute of the same name.  This form of context
  3474 declaration works particularly well with commands 'declare' or
  3475 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3476 very easy to avoid global references, which would not observe Isar
  3477 toplevel undo/redo and fail to work with multithreading.
  3478 
  3479 Various global ML references of Pure and HOL have been turned into
  3480 configuration options:
  3481 
  3482   Unify.search_bound		unify_search_bound
  3483   Unify.trace_bound		unify_trace_bound
  3484   Unify.trace_simp		unify_trace_simp
  3485   Unify.trace_types		unify_trace_types
  3486   Simplifier.simp_depth_limit	simp_depth_limit
  3487   Blast.depth_limit		blast_depth_limit
  3488   DatatypeProp.dtK		datatype_distinctness_limit
  3489   fast_arith_neq_limit  	fast_arith_neq_limit
  3490   fast_arith_split_limit	fast_arith_split_limit
  3491 
  3492 * Named collections of theorems may be easily installed as context
  3493 data using the functor NamedThmsFun (see also
  3494 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3495 attributes; there is also a toplevel print command.  This facility is
  3496 just a common case of general context data, which is the preferred way
  3497 for anything more complex than just a list of facts in canonical
  3498 order.
  3499 
  3500 * Isar: command 'declaration' augments a local theory by generic
  3501 declaration functions written in ML.  This enables arbitrary content
  3502 being added to the context, depending on a morphism that tells the
  3503 difference of the original declaration context wrt. the application
  3504 context encountered later on.
  3505 
  3506 * Isar: proper interfaces for simplification procedures.  Command
  3507 'simproc_setup' declares named simprocs (with match patterns, and body
  3508 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3509 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3510 
  3511 * Isar: an extra pair of brackets around attribute declarations
  3512 abbreviates a theorem reference involving an internal dummy fact,
  3513 which will be ignored later --- only the effect of the attribute on
  3514 the background context will persist.  This form of in-place
  3515 declarations is particularly useful with commands like 'declare' and
  3516 'using', for example ``have A using [[simproc a]] by simp''.
  3517 
  3518 * Isar: method "assumption" (and implicit closing of subproofs) now
  3519 takes simple non-atomic goal assumptions into account: after applying
  3520 an assumption as a rule the resulting subgoals are solved by atomic
  3521 assumption steps.  This is particularly useful to finish 'obtain'
  3522 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3523 without referring to the original premise "!!x. P x ==> thesis" in the
  3524 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3525 more permissive.
  3526 
  3527 * Isar: implicit use of prems from the Isar proof context is
  3528 considered a legacy feature.  Common applications like ``have A .''
  3529 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3530 referencing facts explicitly here improves readability and
  3531 maintainability of proof texts.
  3532 
  3533 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3534 the obtained context from the course of reasoning!  For example:
  3535 
  3536   assume "EX x y. A x & B y"   -- "any previous fact"
  3537   then guess x and y by clarify
  3538 
  3539 This technique is potentially adventurous, depending on the facts and
  3540 proof tools being involved here.
  3541 
  3542 * Isar: known facts from the proof context may be specified as literal
  3543 propositions, using ASCII back-quote syntax.  This works wherever
  3544 named facts used to be allowed so far, in proof commands, proof
  3545 methods, attributes etc.  Literal facts are retrieved from the context
  3546 according to unification of type and term parameters.  For example,
  3547 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3548 theorems in the current context, then these are valid literal facts:
  3549 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3550 
  3551 There is also a proof method "fact" which does the same composition
  3552 for explicit goal states, e.g. the following proof texts coincide with
  3553 certain special cases of literal facts:
  3554 
  3555   have "A" by fact                 ==  note `A`
  3556   have "A ==> B" by fact           ==  note `A ==> B`
  3557   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3558   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3559 
  3560 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3561 outer syntax.  Thus symbolic identifiers may be used without
  3562 additional white space in declarations like this: ``assume *: A''.
  3563 
  3564 * Isar: 'print_facts' prints all local facts of the current context,
  3565 both named and unnamed ones.
  3566 
  3567 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3568 
  3569   def x == "t" and y == "u"
  3570 
  3571 * Isar: added command 'unfolding', which is structurally similar to
  3572 'using', but affects both the goal state and facts by unfolding given
  3573 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3574 'unfolded' attribute may be replaced by first-class proof text.
  3575 
  3576 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3577 and command 'unfolding' now all support object-level equalities
  3578 (potentially conditional).  The underlying notion of rewrite rule is
  3579 analogous to the 'rule_format' attribute, but *not* that of the
  3580 Simplifier (which is usually more generous).
  3581 
  3582 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3583 premises of a theorem by n. Useful in conjunction with drule.
  3584 
  3585 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3586 method expression within a sandbox consisting of the first N
  3587 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3588 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3589 simplifies all new goals that emerge from applying rule foo to the
  3590 originally first one.
  3591 
  3592 * Isar: schematic goals are no longer restricted to higher-order
  3593 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3594 expected.
  3595 
  3596 * Isar: the conclusion of a long theorem statement is now either
  3597 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3598 (essentially a disjunction of cases with local parameters and
  3599 assumptions).  The latter allows to express general elimination rules
  3600 adequately; in this notation common elimination rules look like this:
  3601 
  3602   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3603     assumes "EX x. P x"
  3604     obtains x where "P x"
  3605 
  3606   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3607     assumes "A & B"
  3608     obtains A and B
  3609 
  3610   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3611     assumes "A | B"
  3612     obtains
  3613       A
  3614     | B
  3615 
  3616 The subsequent classical rules even refer to the formal "thesis"
  3617 explicitly:
  3618 
  3619   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3620     obtains "~ thesis"
  3621 
  3622   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3623     obtains "thesis ==> something"
  3624 
  3625 The actual proof of an 'obtains' statement is analogous to that of the
  3626 Isar proof element 'obtain', only that there may be several cases.
  3627 Optional case names may be specified in parentheses; these will be
  3628 available both in the present proof and as annotations in the
  3629 resulting rule, for later use with the 'cases' method (cf. attribute
  3630 case_names).
  3631 
  3632 * Isar: the assumptions of a long theorem statement are available as
  3633 "assms" fact in the proof context.  This is more appropriate than the
  3634 (historical) "prems", which refers to all assumptions of the current
  3635 context, including those from the target locale, proof body etc.
  3636 
  3637 * Isar: 'print_statement' prints theorems from the current theory or
  3638 proof context in long statement form, according to the syntax of a
  3639 top-level lemma.
  3640 
  3641 * Isar: 'obtain' takes an optional case name for the local context
  3642 introduction rule (default "that").
  3643 
  3644 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3645 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3646 to occur.
  3647 
  3648 * Pure: syntax "CONST name" produces a fully internalized constant
  3649 according to the current context.  This is particularly useful for
  3650 syntax translations that should refer to internal constant
  3651 representations independently of name spaces.
  3652 
  3653 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3654 instead of "FOO ". This allows multiple binder declarations to coexist
  3655 in the same context.  INCOMPATIBILITY.
  3656 
  3657 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3658 primitive that also works in a locale context (both for constants and
  3659 fixed variables). Type declaration and internal syntactic representation
  3660 of given constants retrieved from the context. Likewise, the
  3661 'no_notation' command allows to remove given syntax annotations from the
  3662 current context.
  3663 
  3664 * Isar/locales: new derived specification elements 'axiomatization',
  3665 'definition', 'abbreviation', which support type-inference, admit
  3666 object-level specifications (equality, equivalence).  See also the
  3667 isar-ref manual.  Examples:
  3668 
  3669   axiomatization
  3670     eq  (infix "===" 50) where
  3671     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3672 
  3673   definition "f x y = x + y + 1"
  3674   definition g where "g x = f x x"
  3675 
  3676   abbreviation
  3677     neq  (infix "=!=" 50) where
  3678     "x =!= y == ~ (x === y)"
  3679 
  3680 These specifications may be also used in a locale context.  Then the
  3681 constants being introduced depend on certain fixed parameters, and the
  3682 constant name is qualified by the locale base name.  An internal
  3683 abbreviation takes care for convenient input and output, making the
  3684 parameters implicit and using the original short name.  See also
  3685 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3686 entities from a monomorphic theory.
  3687 
  3688 Presently, abbreviations are only available 'in' a target locale, but
  3689 not inherited by general import expressions.  Also note that
  3690 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3691 'translations' in common applications.  The "no_abbrevs" print mode
  3692 prevents folding of abbreviations in term output.
  3693 
  3694 Concrete syntax is attached to specified constants in internal form,
  3695 independently of name spaces.  The parse tree representation is
  3696 slightly different -- use 'notation' instead of raw 'syntax', and
  3697 'translations' with explicit "CONST" markup to accommodate this.
  3698 
  3699 * Pure/Isar: unified syntax for new-style specification mechanisms
  3700 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3701 full type inference and dummy patterns ("_").  For example:
  3702 
  3703   definition "K x _ = x"
  3704 
  3705   inductive conj for A B
  3706   where "A ==> B ==> conj A B"
  3707 
  3708 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3709 the current context.  Print mode "no_abbrevs" prevents inversion of
  3710 abbreviations on output.
  3711 
  3712 * Isar/locales: improved parameter handling: use of locales "var" and
  3713 "struct" no longer necessary; - parameter renamings are no longer
  3714 required to be injective.  For example, this allows to define
  3715 endomorphisms as locale endom = homom mult mult h.
  3716 
  3717 * Isar/locales: changed the way locales with predicates are defined.
  3718 Instead of accumulating the specification, the imported expression is
  3719 now an interpretation.  INCOMPATIBILITY: different normal form of
  3720 locale expressions.  In particular, in interpretations of locales with
  3721 predicates, goals repesenting already interpreted fragments are not
  3722 removed automatically.  Use methods `intro_locales' and
  3723 `unfold_locales'; see below.
  3724 
  3725 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3726 provide backward reasoning on locales predicates.  The methods are
  3727 aware of interpretations and discharge corresponding goals.
  3728 `intro_locales' is less aggressive then `unfold_locales' and does not
  3729 unfold predicates to assumptions.
  3730 
  3731 * Isar/locales: the order in which locale fragments are accumulated
  3732 has changed.  This enables to override declarations from fragments due
  3733 to interpretations -- for example, unwanted simp rules.
  3734 
  3735 * Isar/locales: interpretation in theories and proof contexts has been
  3736 extended.  One may now specify (and prove) equations, which are
  3737 unfolded in interpreted theorems.  This is useful for replacing
  3738 defined concepts (constants depending on locale parameters) by
  3739 concepts already existing in the target context.  Example:
  3740 
  3741   interpretation partial_order ["op <= :: [int, int] => bool"]
  3742     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3743 
  3744 Typically, the constant `partial_order.less' is created by a
  3745 definition specification element in the context of locale
  3746 partial_order.
  3747 
  3748 * Method "induct": improved internal context management to support
  3749 local fixes and defines on-the-fly. Thus explicit meta-level
  3750 connectives !!  and ==> are rarely required anymore in inductive goals
  3751 (using object-logic connectives for this purpose has been long
  3752 obsolete anyway). Common proof patterns are explained in
  3753 src/HOL/Induct/Common_Patterns.thy, see also
  3754 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3755 examples.
  3756 
  3757 * Method "induct": improved handling of simultaneous goals. Instead of
  3758 introducing object-level conjunction, the statement is now split into
  3759 several conclusions, while the corresponding symbolic cases are nested
  3760 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3761 see src/HOL/Induct/Common_Patterns.thy, for example.
  3762 
  3763 * Method "induct": mutual induction rules are now specified as a list
  3764 of rule sharing the same induction cases. HOL packages usually provide
  3765 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3766 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3767 mutual induction rules differently, i.e. like this:
  3768 
  3769   (induct rule: foo_bar.inducts)
  3770   (induct set: foo bar)
  3771   (induct pred: foo bar)
  3772   (induct type: foo bar)
  3773 
  3774 The ML function ProjectRule.projections turns old-style rules into the
  3775 new format.
  3776 
  3777 * Method "coinduct": dual of induction, see
  3778 src/HOL/Library/Coinductive_List.thy for various examples.
  3779 
  3780 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3781 considered a legacy feature.
  3782 
  3783 * Attribute "symmetric" produces result with standardized schematic
  3784 variables (index 0).  Potential INCOMPATIBILITY.
  3785 
  3786 * Simplifier: by default the simplifier trace only shows top level
  3787 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3788 default. Thus there is less danger of being flooded by the trace. The
  3789 trace indicates where parts have been suppressed.
  3790   
  3791 * Provers/classical: removed obsolete classical version of elim_format
  3792 attribute; classical elim/dest rules are now treated uniformly when
  3793 manipulating the claset.
  3794 
  3795 * Provers/classical: stricter checks to ensure that supplied intro,
  3796 dest and elim rules are well-formed; dest and elim rules must have at
  3797 least one premise.
  3798 
  3799 * Provers/classical: attributes dest/elim/intro take an optional
  3800 weight argument for the rule (just as the Pure versions).  Weights are
  3801 ignored by automated tools, but determine the search order of single
  3802 rule steps.
  3803 
  3804 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3805 where the body does not mention the bound variable.  Note that dummy
  3806 patterns implicitly depend on their context of bounds, which makes
  3807 "{_. _}" match any set comprehension as expected.  Potential
  3808 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3809 constant "_idtdummy" in the binding position.
  3810 
  3811 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3812 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3813 for example "A -> B" => "Pi A (%_. B)".
  3814 
  3815 * Pure: 'class_deps' command visualizes the subclass relation, using
  3816 the graph browser tool.
  3817 
  3818 * Pure: 'print_theory' now suppresses certain internal declarations by
  3819 default; use '!' option for full details.
  3820 
  3821 
  3822 *** HOL ***
  3823 
  3824 * Method "metis" proves goals by applying the Metis general-purpose
  3825 resolution prover (see also http://gilith.com/software/metis/).
  3826 Examples are in the directory MetisExamples.  WARNING: the
  3827 Isabelle/HOL-Metis integration does not yet work properly with
  3828 multi-threading.
  3829   
  3830 * Command 'sledgehammer' invokes external automatic theorem provers as
  3831 background processes.  It generates calls to the "metis" method if
  3832 successful. These can be pasted into the proof.  Users do not have to
  3833 wait for the automatic provers to return.  WARNING: does not really
  3834 work with multi-threading.
  3835 
  3836 * New "auto_quickcheck" feature tests outermost goal statements for
  3837 potential counter-examples.  Controlled by ML references
  3838 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3839 5000 milliseconds).  Fails silently if statements is outside of
  3840 executable fragment, or any other codgenerator problem occurs.
  3841 
  3842 * New constant "undefined" with axiom "undefined x = undefined".
  3843 
  3844 * Added class "HOL.eq", allowing for code generation with polymorphic
  3845 equality.
  3846 
  3847 * Some renaming of class constants due to canonical name prefixing in
  3848 the new 'class' package:
  3849 
  3850     HOL.abs ~> HOL.abs_class.abs
  3851     HOL.divide ~> HOL.divide_class.divide
  3852     0 ~> HOL.zero_class.zero
  3853     1 ~> HOL.one_class.one
  3854     op + ~> HOL.plus_class.plus
  3855     op - ~> HOL.minus_class.minus
  3856     uminus ~> HOL.minus_class.uminus
  3857     op * ~> HOL.times_class.times
  3858     op < ~> HOL.ord_class.less
  3859     op <= > HOL.ord_class.less_eq
  3860     Nat.power ~> Power.power_class.power
  3861     Nat.size ~> Nat.size_class.size
  3862     Numeral.number_of ~> Numeral.number_class.number_of
  3863     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3864     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3865     Orderings.min ~> Orderings.ord_class.min
  3866     Orderings.max ~> Orderings.ord_class.max
  3867     Divides.op div ~> Divides.div_class.div
  3868     Divides.op mod ~> Divides.div_class.mod
  3869     Divides.op dvd ~> Divides.div_class.dvd
  3870 
  3871 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3872 
  3873 a) User-defined constants using any of the names "plus", "minus",
  3874 "times", "less" or "less_eq". The standard syntax translations for
  3875 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3876 names.
  3877 
  3878 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3879 INCOMPATIBILITY: use more specific names.
  3880 
  3881 c) Permutative equations (e.g. "a + b = b + a")
  3882 Since the change of names also changes the order of terms, permutative
  3883 rewrite rules may get applied in a different order. Experience shows
  3884 that this is rarely the case (only two adaptions in the whole Isabelle
  3885 distribution).  INCOMPATIBILITY: rewrite proofs
  3886 
  3887 d) ML code directly refering to constant names
  3888 This in general only affects hand-written proof tactics, simprocs and
  3889 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3890 Consider using @{const_name} antiquotation.
  3891 
  3892 * New class "default" with associated constant "default".
  3893 
  3894 * Function "sgn" is now overloaded and available on int, real, complex
  3895 (and other numeric types), using class "sgn".  Two possible defs of
  3896 sgn are given as equational assumptions in the classes sgn_if and
  3897 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3898 INCOMPATIBILITY.
  3899 
  3900 * Locale "partial_order" now unified with class "order" (cf. theory
  3901 Orderings), added parameter "less".  INCOMPATIBILITY.
  3902 
  3903 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3904 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3905 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3906 
  3907 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3908 changed order of proof goals in instance proofs.
  3909 
  3910 * The transitivity reasoner for partial and linear orders is set up
  3911 for classes "order" and "linorder".  Instances of the reasoner are available
  3912 in all contexts importing or interpreting the corresponding locales.
  3913 Method "order" invokes the reasoner separately; the reasoner
  3914 is also integrated with the Simplifier as a solver.  Diagnostic
  3915 command 'print_orders' shows the available instances of the reasoner
  3916 in the current context.
  3917 
  3918 * Localized monotonicity predicate in theory "Orderings"; integrated
  3919 lemmas max_of_mono and min_of_mono with this predicate.
  3920 INCOMPATIBILITY.
  3921 
  3922 * Formulation of theorem "dense" changed slightly due to integration
  3923 with new class dense_linear_order.
  3924 
  3925 * Uniform lattice theory development in HOL.
  3926 
  3927     constants "meet" and "join" now named "inf" and "sup"
  3928     constant "Meet" now named "Inf"
  3929 
  3930     classes "meet_semilorder" and "join_semilorder" now named
  3931       "lower_semilattice" and "upper_semilattice"
  3932     class "lorder" now named "lattice"
  3933     class "comp_lat" now named "complete_lattice"
  3934 
  3935     Instantiation of lattice classes allows explicit definitions
  3936     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3937 
  3938   INCOMPATIBILITY.  Theorem renames:
  3939 
  3940     meet_left_le            ~> inf_le1
  3941     meet_right_le           ~> inf_le2
  3942     join_left_le            ~> sup_ge1
  3943     join_right_le           ~> sup_ge2
  3944     meet_join_le            ~> inf_sup_ord
  3945     le_meetI                ~> le_infI
  3946     join_leI                ~> le_supI
  3947     le_meet                 ~> le_inf_iff
  3948     le_join                 ~> ge_sup_conv
  3949     meet_idempotent         ~> inf_idem
  3950     join_idempotent         ~> sup_idem
  3951     meet_comm               ~> inf_commute
  3952     join_comm               ~> sup_commute
  3953     meet_leI1               ~> le_infI1
  3954     meet_leI2               ~> le_infI2
  3955     le_joinI1               ~> le_supI1
  3956     le_joinI2               ~> le_supI2
  3957     meet_assoc              ~> inf_assoc
  3958     join_assoc              ~> sup_assoc
  3959     meet_left_comm          ~> inf_left_commute
  3960     meet_left_idempotent    ~> inf_left_idem
  3961     join_left_comm          ~> sup_left_commute
  3962     join_left_idempotent    ~> sup_left_idem
  3963     meet_aci                ~> inf_aci
  3964     join_aci                ~> sup_aci
  3965     le_def_meet             ~> le_iff_inf
  3966     le_def_join             ~> le_iff_sup
  3967     join_absorp2            ~> sup_absorb2
  3968     join_absorp1            ~> sup_absorb1
  3969     meet_absorp1            ~> inf_absorb1
  3970     meet_absorp2            ~> inf_absorb2
  3971     meet_join_absorp        ~> inf_sup_absorb
  3972     join_meet_absorp        ~> sup_inf_absorb
  3973     distrib_join_le         ~> distrib_sup_le
  3974     distrib_meet_le         ~> distrib_inf_le
  3975 
  3976     add_meet_distrib_left   ~> add_inf_distrib_left
  3977     add_join_distrib_left   ~> add_sup_distrib_left
  3978     is_join_neg_meet        ~> is_join_neg_inf
  3979     is_meet_neg_join        ~> is_meet_neg_sup
  3980     add_meet_distrib_right  ~> add_inf_distrib_right
  3981     add_join_distrib_right  ~> add_sup_distrib_right
  3982     add_meet_join_distribs  ~> add_sup_inf_distribs
  3983     join_eq_neg_meet        ~> sup_eq_neg_inf
  3984     meet_eq_neg_join        ~> inf_eq_neg_sup
  3985     add_eq_meet_join        ~> add_eq_inf_sup
  3986     meet_0_imp_0            ~> inf_0_imp_0
  3987     join_0_imp_0            ~> sup_0_imp_0
  3988     meet_0_eq_0             ~> inf_0_eq_0
  3989     join_0_eq_0             ~> sup_0_eq_0
  3990     neg_meet_eq_join        ~> neg_inf_eq_sup
  3991     neg_join_eq_meet        ~> neg_sup_eq_inf
  3992     join_eq_if              ~> sup_eq_if
  3993 
  3994     mono_meet               ~> mono_inf
  3995     mono_join               ~> mono_sup
  3996     meet_bool_eq            ~> inf_bool_eq
  3997     join_bool_eq            ~> sup_bool_eq
  3998     meet_fun_eq             ~> inf_fun_eq
  3999     join_fun_eq             ~> sup_fun_eq
  4000     meet_set_eq             ~> inf_set_eq
  4001     join_set_eq             ~> sup_set_eq
  4002     meet1_iff               ~> inf1_iff
  4003     meet2_iff               ~> inf2_iff
  4004     meet1I                  ~> inf1I
  4005     meet2I                  ~> inf2I
  4006     meet1D1                 ~> inf1D1
  4007     meet2D1                 ~> inf2D1
  4008     meet1D2                 ~> inf1D2
  4009     meet2D2                 ~> inf2D2
  4010     meet1E                  ~> inf1E
  4011     meet2E                  ~> inf2E
  4012     join1_iff               ~> sup1_iff
  4013     join2_iff               ~> sup2_iff
  4014     join1I1                 ~> sup1I1
  4015     join2I1                 ~> sup2I1
  4016     join1I1                 ~> sup1I1
  4017     join2I2                 ~> sup1I2
  4018     join1CI                 ~> sup1CI
  4019     join2CI                 ~> sup2CI
  4020     join1E                  ~> sup1E
  4021     join2E                  ~> sup2E
  4022 
  4023     is_meet_Meet            ~> is_meet_Inf
  4024     Meet_bool_def           ~> Inf_bool_def
  4025     Meet_fun_def            ~> Inf_fun_def
  4026     Meet_greatest           ~> Inf_greatest
  4027     Meet_lower              ~> Inf_lower
  4028     Meet_set_def            ~> Inf_set_def
  4029 
  4030     Sup_def                 ~> Sup_Inf
  4031     Sup_bool_eq             ~> Sup_bool_def
  4032     Sup_fun_eq              ~> Sup_fun_def
  4033     Sup_set_eq              ~> Sup_set_def
  4034 
  4035     listsp_meetI            ~> listsp_infI
  4036     listsp_meet_eq          ~> listsp_inf_eq
  4037 
  4038     meet_min                ~> inf_min
  4039     join_max                ~> sup_max
  4040 
  4041 * Added syntactic class "size"; overloaded constant "size" now has
  4042 type "'a::size ==> bool"
  4043 
  4044 * Internal reorganisation of `size' of datatypes: size theorems
  4045 "foo.size" are no longer subsumed by "foo.simps" (but are still
  4046 simplification rules by default!); theorems "prod.size" now named
  4047 "*.size".
  4048 
  4049 * Class "div" now inherits from class "times" rather than "type".
  4050 INCOMPATIBILITY.
  4051 
  4052 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  4053 Linorder etc.  have disappeared; operations defined in terms of
  4054 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  4055 
  4056 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  4057 
  4058 * HOL-Word: New extensive library and type for generic, fixed size
  4059 machine words, with arithemtic, bit-wise, shifting and rotating
  4060 operations, reflection into int, nat, and bool lists, automation for
  4061 linear arithmetic (by automatic reflection into nat or int), including
  4062 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  4063 arithmetic type classes, supporting automatic simplification of
  4064 numerals on all operations.
  4065 
  4066 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  4067 
  4068 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  4069 
  4070 * Code generator library theories:
  4071   - Code_Integer represents HOL integers by big integer literals in target
  4072     languages.
  4073   - Code_Char represents HOL characters by character literals in target
  4074     languages.
  4075   - Code_Char_chr like Code_Char, but also offers treatment of character
  4076     codes; includes Code_Integer.
  4077   - Executable_Set allows to generate code for finite sets using lists.
  4078   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  4079     denominator).
  4080   - Executable_Real implements a subset of real numbers, namly those
  4081     representable by rational numbers.
  4082   - Efficient_Nat implements natural numbers by integers, which in general will
  4083     result in higher efficency; pattern matching with 0/Suc is eliminated;
  4084     includes Code_Integer.
  4085   - Code_Index provides an additional datatype index which is mapped to
  4086     target-language built-in integers.
  4087   - Code_Message provides an additional datatype message_string which is isomorphic to
  4088     strings; messages are mapped to target-language strings.
  4089 
  4090 * New package for inductive predicates
  4091 
  4092   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  4093 
  4094     inductive
  4095       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4096       for z_1 :: U_1 and ... and z_n :: U_m
  4097     where
  4098       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4099     | ...
  4100 
  4101   with full support for type-inference, rather than
  4102 
  4103     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4104 
  4105     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4106     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4107 
  4108     inductive "s z_1 ... z_m"
  4109     intros
  4110       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4111       ...
  4112 
  4113   For backward compatibility, there is a wrapper allowing inductive
  4114   sets to be defined with the new package via
  4115 
  4116     inductive_set
  4117       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4118       for z_1 :: U_1 and ... and z_n :: U_m
  4119     where
  4120       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4121     | ...
  4122 
  4123   or
  4124 
  4125     inductive_set
  4126       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4127       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4128       for z_1 :: U_1 and ... and z_n :: U_m
  4129     where
  4130       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4131     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4132     | ...
  4133 
  4134   if the additional syntax "p ..." is required.
  4135 
  4136   Numerous examples can be found in the subdirectories src/HOL/Auth,
  4137   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  4138 
  4139   INCOMPATIBILITIES:
  4140 
  4141   - Since declaration and definition of inductive sets or predicates
  4142     is no longer separated, abbreviations involving the newly
  4143     introduced sets or predicates must be specified together with the
  4144     introduction rules after the 'where' keyword (see above), rather
  4145     than before the actual inductive definition.
  4146 
  4147   - The variables in induction and elimination rules are now
  4148     quantified in the order of their occurrence in the introduction
  4149     rules, rather than in alphabetical order. Since this may break
  4150     some proofs, these proofs either have to be repaired, e.g. by
  4151     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  4152     statements of the form
  4153 
  4154       case (rule_i a_i_1 ... a_i_{k_i})
  4155 
  4156     or the old order of quantification has to be restored by explicitly adding
  4157     meta-level quantifiers in the introduction rules, i.e.
  4158 
  4159       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  4160 
  4161   - The format of the elimination rules is now
  4162 
  4163       p z_1 ... z_m x_1 ... x_n ==>
  4164         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4165         ==> ... ==> P
  4166 
  4167     for predicates and
  4168 
  4169       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4170         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4171         ==> ... ==> P
  4172 
  4173     for sets rather than
  4174 
  4175       x : s z_1 ... z_m ==>
  4176         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4177         ==> ... ==> P
  4178 
  4179     This may require terms in goals to be expanded to n-tuples
  4180     (e.g. using case_tac or simplification with the split_paired_all
  4181     rule) before the above elimination rule is applicable.
  4182 
  4183   - The elimination or case analysis rules for (mutually) inductive
  4184     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4185     list of rules "p_1_..._p_k.elims" is no longer available.
  4186 
  4187 * New package "function"/"fun" for general recursive functions,
  4188 supporting mutual and nested recursion, definitions in local contexts,
  4189 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4190 for small examples, and the separate tutorial on the function
  4191 package. The old recdef "package" is still available as before, but
  4192 users are encouraged to use the new package.
  4193 
  4194 * Method "lexicographic_order" automatically synthesizes termination
  4195 relations as lexicographic combinations of size measures. 
  4196 
  4197 * Case-expressions allow arbitrary constructor-patterns (including
  4198 "_") and take their order into account, like in functional
  4199 programming.  Internally, this is translated into nested
  4200 case-expressions; missing cases are added and mapped to the predefined
  4201 constant "undefined". In complicated cases printing may no longer show
  4202 the original input but the internal form. Lambda-abstractions allow
  4203 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4204 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4205 variable.
  4206 
  4207 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4208 is an abbreviation for "of_nat :: nat => int". The simplification
  4209 rules for "of_nat" have been changed to work like "int" did
  4210 previously.  Potential INCOMPATIBILITY:
  4211   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4212   - of_nat_diff and of_nat_mult are no longer default simp rules
  4213 
  4214 * Method "algebra" solves polynomial equations over (semi)rings using
  4215 Groebner bases. The (semi)ring structure is defined by locales and the
  4216 tool setup depends on that generic context. Installing the method for
  4217 a specific type involves instantiating the locale and possibly adding
  4218 declarations for computation on the coefficients.  The method is
  4219 already instantiated for natural numbers and for the axiomatic class
  4220 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4221 CALCULEMUS 2007 for the general principles underlying this
  4222 architecture of context-aware proof-tools.
  4223 
  4224 * Method "ferrack" implements quantifier elimination over
  4225 special-purpose dense linear orders using locales (analogous to
  4226 "algebra"). The method is already installed for class
  4227 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4228 rat, etc.
  4229 
  4230 * Former constant "List.op @" now named "List.append".  Use ML
  4231 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4232 circumvent possible incompatibilities when working on ML level.
  4233 
  4234 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4235 
  4236 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4237 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4238 
  4239 * New syntax for Haskell-like list comprehension (input only), eg.
  4240 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4241 
  4242 * The special syntax for function "filter" has changed from [x :
  4243 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4244 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4245 
  4246 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4247 defined on nat only, as an abbreviation for [a..<Suc b]
  4248 INCOMPATIBILITY.
  4249 
  4250 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4251 
  4252 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4253 
  4254 * New lemma collection field_simps (an extension of ring_simps) for
  4255 manipulating (in)equations involving division. Multiplies with all
  4256 denominators that can be proved to be non-zero (in equations) or
  4257 positive/negative (in inequations).
  4258 
  4259 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4260 have been improved and renamed to ring_simps, group_simps and
  4261 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4262 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4263 
  4264 * Theory Library/Commutative_Ring: switched from recdef to function
  4265 package; constants add, mul, pow now curried.  Infix syntax for
  4266 algebraic operations.
  4267 
  4268 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4269 INCOMPATIBILITY.
  4270 
  4271 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4272 INCOMPATIBILITY.
  4273 
  4274 * HOL/records: generalised field-update to take a function on the
  4275 field rather than the new value: r(|A := x|) is translated to A_update
  4276 (K x) r The K-combinator that is internally used is called K_record.
  4277 INCOMPATIBILITY: Usage of the plain update functions has to be
  4278 adapted.
  4279  
  4280 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4281 * x = 0, which are required for a semiring.  Richer structures do not
  4282 inherit from semiring_0 anymore, because this property is a theorem
  4283 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4284 there is more to prove, but this is mostly trivial.
  4285 
  4286 * Class "recpower" is generalized to arbitrary monoids, not just
  4287 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4288 commutativity or semiring properties additionally.
  4289 
  4290 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4291 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4292 better use 'abbreviation'.
  4293 
  4294 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4295 
  4296 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4297 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4298 significant changes for setting up numeral syntax for types:
  4299   - New constants Numeral.pred and Numeral.succ instead
  4300       of former Numeral.bin_pred and Numeral.bin_succ.
  4301   - Use integer operations instead of bin_add, bin_mult and so on.
  4302   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4303   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4304 
  4305 See src/HOL/Integ/IntArith.thy for an example setup.
  4306 
  4307 * Command 'normal_form' computes the normal form of a term that may
  4308 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4309 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4310 heavy-duty computations because the functions are compiled to ML
  4311 first.  Correspondingly, a method "normalization" is provided.  See
  4312 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4313 
  4314 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4315 25 like -->); output depends on the "iff" print_mode, the default is
  4316 "A = B" (with priority 50).
  4317 
  4318 * Relations less (<) and less_eq (<=) are also available on type bool.
  4319 Modified syntax to disallow nesting without explicit parentheses,
  4320 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4321 INCOMPATIBILITY.
  4322 
  4323 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4324 
  4325 * Relation composition operator "op O" now has precedence 75 and binds
  4326 stronger than union and intersection. INCOMPATIBILITY.
  4327 
  4328 * The old set interval syntax "{m..n(}" (and relatives) has been
  4329 removed.  Use "{m..<n}" (and relatives) instead.
  4330 
  4331 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4332 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4333 ``declare [[simproc del: neq]]''.
  4334 
  4335 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4336 True/False.
  4337 
  4338 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4339 
  4340 * Theorem setsum_mult renamed to setsum_right_distrib.
  4341 
  4342 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4343 ``rule'' method.
  4344 
  4345 * Reimplemented methods "sat" and "satx", with several improvements:
  4346 goals no longer need to be stated as "<prems> ==> False", equivalences
  4347 (i.e. "=" on type bool) are handled, variable names of the form
  4348 "lit_<n>" are no longer reserved, significant speedup.
  4349 
  4350 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4351 zChaff is still supported as well.
  4352 
  4353 * 'inductive' and 'datatype': provide projections of mutual rules,
  4354 bundled as foo_bar.inducts;
  4355 
  4356 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4357 Library.
  4358 
  4359 * Library: moved theory Accessible_Part to main HOL.
  4360 
  4361 * Library: added theory Coinductive_List of potentially infinite lists
  4362 as greatest fixed-point.
  4363 
  4364 * Library: added theory AssocList which implements (finite) maps as
  4365 association lists.
  4366 
  4367 * Method "evaluation" solves goals (i.e. a boolean expression)
  4368 efficiently by compiling it to ML.  The goal is "proved" (via an
  4369 oracle) if it evaluates to True.
  4370 
  4371 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4372 also when invoked by the simplifier.  This results in the Simplifier
  4373 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4374 Configuration option fast_arith_split_limit=0 recovers the old
  4375 behavior.
  4376 
  4377 * Support for hex (0x20) and binary (0b1001) numerals.
  4378 
  4379 * New method: reify eqs (t), where eqs are equations for an
  4380 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4381 parameter, computes a term s::'b and a list xs::'a list and proves the
  4382 theorem I xs s = t. This is also known as reification or quoting. The
  4383 resulting theorem is applied to the subgoal to substitute t with I xs
  4384 s.  If t is omitted, the subgoal itself is reified.
  4385 
  4386 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4387 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4388 where f is supposed to be a computable function (in the sense of code
  4389 generattion). The method uses reify to compute s and xs as above then
  4390 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4391 r and finally gets the theorem t = r, which is again applied to the
  4392 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4393 
  4394 * Reflection: Automatic reification now handels binding, an example is
  4395 available in src/HOL/ex/ReflectionEx.thy
  4396 
  4397 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4398 command 'statespace' that is similar to 'record', but introduces an
  4399 abstract specification based on the locale infrastructure instead of
  4400 HOL types.  This leads to extra flexibility in composing state spaces,
  4401 in particular multiple inheritance and renaming of components.
  4402 
  4403 
  4404 *** HOL-Complex ***
  4405 
  4406 * Hyperreal: Functions root and sqrt are now defined on negative real
  4407 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4408 Nonnegativity side conditions have been removed from many lemmas, so
  4409 that more subgoals may now be solved by simplification; potential
  4410 INCOMPATIBILITY.
  4411 
  4412 * Real: new type classes formalize real normed vector spaces and
  4413 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4414 and norm :: 'a => real.
  4415 
  4416 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4417 reals into other types. The overloaded constant Reals :: 'a set is now
  4418 defined as range of_real; potential INCOMPATIBILITY.
  4419 
  4420 * Real: proper support for ML code generation, including 'quickcheck'.
  4421 Reals are implemented as arbitrary precision rationals.
  4422 
  4423 * Hyperreal: Several constants that previously worked only for the
  4424 reals have been generalized, so they now work over arbitrary vector
  4425 spaces. Type annotations may need to be added in some cases; potential
  4426 INCOMPATIBILITY.
  4427 
  4428   Infinitesimal  :: ('a::real_normed_vector) star set
  4429   HFinite        :: ('a::real_normed_vector) star set
  4430   HInfinite      :: ('a::real_normed_vector) star set
  4431   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4432   monad          :: ('a::real_normed_vector) star => 'a star set
  4433   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4434   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4435   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4436   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4437   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4438   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4439   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4440   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4441   sgn            :: 'a::real_normed_vector => 'a
  4442   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4443 
  4444 * Complex: Some complex-specific constants are now abbreviations for
  4445 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4446 hnorm.  Other constants have been entirely removed in favor of the
  4447 polymorphic versions (INCOMPATIBILITY):
  4448 
  4449   approx        <-- capprox
  4450   HFinite       <-- CFinite
  4451   HInfinite     <-- CInfinite
  4452   Infinitesimal <-- CInfinitesimal
  4453   monad         <-- cmonad
  4454   galaxy        <-- cgalaxy
  4455   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4456   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4457   (ns)deriv     <-- (ns)cderiv
  4458 
  4459 
  4460 *** HOL-Algebra ***
  4461 
  4462 * Formalisation of ideals and the quotient construction over rings.
  4463 
  4464 * Order and lattice theory no longer based on records.
  4465 INCOMPATIBILITY.
  4466 
  4467 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4468 greatest_closed.  INCOMPATIBILITY.
  4469 
  4470 * Method algebra is now set up via an attribute.  For examples see
  4471 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4472 of algebraic structures.
  4473 
  4474 * Renamed theory CRing to Ring.
  4475 
  4476 
  4477 *** HOL-Nominal ***
  4478 
  4479 * Substantial, yet incomplete support for nominal datatypes (binding
  4480 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4481 src/HOL/Nominal/Examples.  Prospective users should consult
  4482 http://isabelle.in.tum.de/nominal/
  4483 
  4484 
  4485 *** ML ***
  4486 
  4487 * ML basics: just one true type int, which coincides with IntInf.int
  4488 (even on SML/NJ).
  4489 
  4490 * ML within Isar: antiquotations allow to embed statically-checked
  4491 formal entities in the source, referring to the context available at
  4492 compile-time.  For example:
  4493 
  4494 ML {* @{sort "{zero,one}"} *}
  4495 ML {* @{typ "'a => 'b"} *}
  4496 ML {* @{term "%x. x"} *}
  4497 ML {* @{prop "x == y"} *}
  4498 ML {* @{ctyp "'a => 'b"} *}
  4499 ML {* @{cterm "%x. x"} *}
  4500 ML {* @{cprop "x == y"} *}
  4501 ML {* @{thm asm_rl} *}
  4502 ML {* @{thms asm_rl} *}
  4503 ML {* @{type_name c} *}
  4504 ML {* @{type_syntax c} *}
  4505 ML {* @{const_name c} *}
  4506 ML {* @{const_syntax c} *}
  4507 ML {* @{context} *}
  4508 ML {* @{theory} *}
  4509 ML {* @{theory Pure} *}
  4510 ML {* @{theory_ref} *}
  4511 ML {* @{theory_ref Pure} *}
  4512 ML {* @{simpset} *}
  4513 ML {* @{claset} *}
  4514 ML {* @{clasimpset} *}
  4515 
  4516 The same works for sources being ``used'' within an Isar context.
  4517 
  4518 * ML in Isar: improved error reporting; extra verbosity with
  4519 ML_Context.trace enabled.
  4520 
  4521 * Pure/General/table.ML: the join operations now works via exceptions
  4522 DUP/SAME instead of type option. This is simpler in simple cases, and
  4523 admits slightly more efficient complex applications.
  4524 
  4525 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4526 use Context.generic instead of just theory.
  4527 
  4528 * Pure: datatype Context.generic joins theory/Proof.context and
  4529 provides some facilities for code that works in either kind of
  4530 context, notably GenericDataFun for uniform theory and proof data.
  4531 
  4532 * Pure: simplified internal attribute type, which is now always
  4533 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4534 local (Proof.context) attributes have been discontinued, while
  4535 minimizing code duplication. Thm.rule_attribute and
  4536 Thm.declaration_attribute build canonical attributes; see also structure
  4537 Context for further operations on Context.generic, notably
  4538 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4539 declarations and definitions.
  4540 
  4541 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4542 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4543 init only required for impure data. INCOMPATIBILITY: empty really need
  4544 to be empty (no dependencies on theory content!)
  4545 
  4546 * Pure/kernel: consts certification ignores sort constraints given in
  4547 signature declarations. (This information is not relevant to the
  4548 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4549 potential INCOMPATIBILITY.
  4550 
  4551 * Pure: axiomatic type classes are now purely definitional, with
  4552 explicit proofs of class axioms and super class relations performed
  4553 internally. See Pure/axclass.ML for the main internal interfaces --
  4554 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4555 AxClass.axiomatize_class/classrel/arity supersede
  4556 Sign.add_classes/classrel/arities.
  4557 
  4558 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4559 global/local versions on theory vs. Proof.context have been
  4560 discontinued; Attrib.syntax and Method.syntax have been adapted
  4561 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4562 attributes, methods, etc.
  4563 
  4564 * Pure: several functions of signature "... -> theory -> theory * ..."
  4565 have been reoriented to "... -> theory -> ... * theory" in order to
  4566 allow natural usage in combination with the ||>, ||>>, |-> and
  4567 fold_map combinators.
  4568 
  4569 * Pure: official theorem names (closed derivations) and additional
  4570 comments (tags) are now strictly separate.  Name hints -- which are
  4571 maintained as tags -- may be attached any time without affecting the
  4572 derivation.
  4573 
  4574 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4575 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4576 achieve the old behaviour.
  4577 
  4578 * Pure: the "Goal" constant is now called "prop", supporting a
  4579 slightly more general idea of ``protecting'' meta-level rule
  4580 statements.
  4581 
  4582 * Pure: Logic.(un)varify only works in a global context, which is now
  4583 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4584 Logic.legacy_(un)varify as temporary workaround.
  4585 
  4586 * Pure: structure Name provides scalable operations for generating
  4587 internal variable names, notably Name.variants etc.  This replaces
  4588 some popular functions from term.ML:
  4589 
  4590   Term.variant		->  Name.variant
  4591   Term.variantlist	->  Name.variant_list
  4592   Term.invent_names	->  Name.invent_list
  4593 
  4594 Note that low-level renaming rarely occurs in new code -- operations
  4595 from structure Variable are used instead (see below).
  4596 
  4597 * Pure: structure Variable provides fundamental operations for proper
  4598 treatment of fixed/schematic variables in a context.  For example,
  4599 Variable.import introduces fixes for schematics of given facts and
  4600 Variable.export reverses the effect (up to renaming) -- this replaces
  4601 various freeze_thaw operations.
  4602 
  4603 * Pure: structure Goal provides simple interfaces for
  4604 init/conclude/finish and tactical prove operations (replacing former
  4605 Tactic.prove).  Goal.prove is the canonical way to prove results
  4606 within a given context; Goal.prove_global is a degraded version for
  4607 theory level goals, including a global Drule.standard.  Note that
  4608 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4609 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4610 in a locale context).
  4611 
  4612 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4613 and type checking (Syntax.check_term etc.), with common combinations
  4614 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4615 which are considered legacy and await removal.
  4616 
  4617 * Pure/Syntax: generic interfaces for type unchecking
  4618 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4619 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4620 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4621 available for convenience, but refer to the very same operations using
  4622 a mere theory instead of a full context.
  4623 
  4624 * Isar: simplified treatment of user-level errors, using exception
  4625 ERROR of string uniformly.  Function error now merely raises ERROR,
  4626 without any side effect on output channels.  The Isar toplevel takes
  4627 care of proper display of ERROR exceptions.  ML code may use plain
  4628 handle/can/try; cat_error may be used to concatenate errors like this:
  4629 
  4630   ... handle ERROR msg => cat_error msg "..."
  4631 
  4632 Toplevel ML code (run directly or through the Isar toplevel) may be
  4633 embedded into the Isar toplevel with exception display/debug like
  4634 this:
  4635 
  4636   Isar.toplevel (fn () => ...)
  4637 
  4638 INCOMPATIBILITY, removed special transform_error facilities, removed
  4639 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4640 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4641 -- use plain ERROR instead.
  4642 
  4643 * Isar: theory setup now has type (theory -> theory), instead of a
  4644 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4645 
  4646 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4647 ProofContext.debug/verbose flags.
  4648 
  4649 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4650 theory before entering a proof state.  Transactions now always see a
  4651 quasi-functional intermediate checkpoint, both in interactive and
  4652 batch mode.
  4653 
  4654 * Isar: simplified interfaces for outer syntax.  Renamed
  4655 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4656 OuterSyntax.add_parsers -- this functionality is now included in
  4657 OuterSyntax.command etc.  INCOMPATIBILITY.
  4658 
  4659 * Simplifier: the simpset of a running simplification process now
  4660 contains a proof context (cf. Simplifier.the_context), which is the
  4661 very context that the initial simpset has been retrieved from (by
  4662 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4663 (solver, looper etc.) may depend on arbitrary proof data.
  4664 
  4665 * Simplifier.inherit_context inherits the proof context (plus the
  4666 local bounds) of the current simplification process; any simproc
  4667 etc. that calls the Simplifier recursively should do this!  Removed
  4668 former Simplifier.inherit_bounds, which is already included here --
  4669 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4670 specify an explicit context using Simplifier.context/theory_context.
  4671 
  4672 * Simplifier/Classical Reasoner: more abstract interfaces
  4673 change_simpset/claset for modifying the simpset/claset reference of a
  4674 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4675 INCOMPATIBILITY.
  4676 
  4677 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4678 "Trueprop" etc.
  4679 
  4680 
  4681 *** System ***
  4682 
  4683 * settings: the default heap location within ISABELLE_HOME_USER now
  4684 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4685 Isabelle installations.
  4686 
  4687 * isabelle-process: option -S (secure mode) disables some critical
  4688 operations, notably runtime compilation and evaluation of ML source
  4689 code.
  4690 
  4691 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4692 
  4693 * Support for parallel execution, using native multicore support of
  4694 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4695 independent theories, according to the given theory header
  4696 specifications. The maximum number of worker threads is specified via
  4697 usedir option -M or the "max-threads" setting in Proof General. A
  4698 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4699 to 6 on a 8-core machine.  User-code needs to observe certain
  4700 guidelines for thread-safe programming, see appendix A in the Isar
  4701 Implementation manual.
  4702 
  4703 
  4704 
  4705 New in Isabelle2005 (October 2005)
  4706 ----------------------------------
  4707 
  4708 *** General ***
  4709 
  4710 * Theory headers: the new header syntax for Isar theories is
  4711 
  4712   theory <name>
  4713   imports <theory1> ... <theoryN>
  4714   uses <file1> ... <fileM>
  4715   begin
  4716 
  4717 where the 'uses' part is optional.  The previous syntax
  4718 
  4719   theory <name> = <theory1> + ... + <theoryN>:
  4720 
  4721 will disappear in the next release.  Use isatool fixheaders to convert
  4722 existing theory files.  Note that there is no change in ancient
  4723 non-Isar theories now, but these will disappear soon.
  4724 
  4725 * Theory loader: parent theories can now also be referred to via
  4726 relative and absolute paths.
  4727 
  4728 * Command 'find_theorems' searches for a list of criteria instead of a
  4729 list of constants. Known criteria are: intro, elim, dest, name:string,
  4730 simp:term, and any term. Criteria can be preceded by '-' to select
  4731 theorems that do not match. Intro, elim, dest select theorems that
  4732 match the current goal, name:s selects theorems whose fully qualified
  4733 name contain s, and simp:term selects all simplification rules whose
  4734 lhs match term.  Any other term is interpreted as pattern and selects
  4735 all theorems matching the pattern. Available in ProofGeneral under
  4736 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4737 
  4738   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4739 
  4740 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4741 matching the current goal as introduction rule and not having "HOL."
  4742 in their name (i.e. not being defined in theory HOL).
  4743 
  4744 * Command 'thms_containing' has been discontinued in favour of
  4745 'find_theorems'; INCOMPATIBILITY.
  4746 
  4747 * Communication with Proof General is now 8bit clean, which means that
  4748 Unicode text in UTF-8 encoding may be used within theory texts (both
  4749 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4750 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4751 
  4752   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4753   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4754 
  4755 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4756 Classical Reasoner.  Typical big applications run around 2 times
  4757 faster.
  4758 
  4759 
  4760 *** Document preparation ***
  4761 
  4762 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4763 of raw sources.  Only those symbols that do not require additional
  4764 LaTeX packages (depending on comments in isabellesym.sty) are
  4765 displayed properly, everything else is left verbatim.  isatool display
  4766 and isatool print are used as front ends (these are subject to the
  4767 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4768 
  4769 * Command tags control specific markup of certain regions of text,
  4770 notably folding and hiding.  Predefined tags include "theory" (for
  4771 theory begin and end), "proof" for proof commands, and "ML" for
  4772 commands involving ML code; the additional tags "visible" and
  4773 "invisible" are unused by default.  Users may give explicit tag
  4774 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4775 interpretation of tags is determined by the LaTeX job during document
  4776 preparation: see option -V of isatool usedir, or options -n and -t of
  4777 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4778 \isadroptag.
  4779 
  4780 Several document versions may be produced at the same time via isatool
  4781 usedir (the generated index.html will link all of them).  Typical
  4782 specifications include ''-V document=theory,proof,ML'' to present
  4783 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4784 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4785 these parts without any formal replacement text.  The Isabelle site
  4786 default settings produce ''document'' and ''outline'' versions as
  4787 specified above.
  4788 
  4789 * Several new antiquotations:
  4790 
  4791   @{term_type term} prints a term with its type annotated;
  4792 
  4793   @{typeof term} prints the type of a term;
  4794 
  4795   @{const const} is the same as @{term const}, but checks that the
  4796   argument is a known logical constant;
  4797 
  4798   @{term_style style term} and @{thm_style style thm} print a term or
  4799   theorem applying a "style" to it
  4800 
  4801   @{ML text}
  4802 
  4803 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4804 definitions, equations, inequations etc., 'concl' printing only the
  4805 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4806 to print the specified premise.  TermStyle.add_style provides an ML
  4807 interface for introducing further styles.  See also the "LaTeX Sugar"
  4808 document practical applications.  The ML antiquotation prints
  4809 type-checked ML expressions verbatim.
  4810 
  4811 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4812 and 'text' support optional locale specification '(in loc)', which
  4813 specifies the default context for interpreting antiquotations.  For
  4814 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4815 
  4816 * Option 'locale=NAME' of antiquotations specifies an alternative
  4817 context interpreting the subsequent argument.  For example: @{thm
  4818 [locale=lattice] inf_assoc}.
  4819 
  4820 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4821 a proof context.
  4822 
  4823 * Proper output of antiquotations for theory commands involving a
  4824 proof context (such as 'locale' or 'theorem (in loc) ...').
  4825 
  4826 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4827 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4828 
  4829 * isatool usedir: new option -C (default true) controls whether option
  4830 -D should include a copy of the original document directory; -C false
  4831 prevents unwanted effects such as copying of administrative CVS data.
  4832 
  4833 
  4834 *** Pure ***
  4835 
  4836 * Considerably improved version of 'constdefs' command.  Now performs
  4837 automatic type-inference of declared constants; additional support for
  4838 local structure declarations (cf. locales and HOL records), see also
  4839 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4840 sequential dependencies of definitions within a single 'constdefs'
  4841 section; moreover, the declared name needs to be an identifier.  If
  4842 all fails, consider to fall back on 'consts' and 'defs' separately.
  4843 
  4844 * Improved indexed syntax and implicit structures.  First of all,
  4845 indexed syntax provides a notational device for subscripted
  4846 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4847 expressions.  Secondly, in a local context with structure
  4848 declarations, number indexes \<^sub>n or the empty index (default
  4849 number 1) refer to a certain fixed variable implicitly; option
  4850 show_structs controls printing of implicit structures.  Typical
  4851 applications of these concepts involve record types and locales.
  4852 
  4853 * New command 'no_syntax' removes grammar declarations (and
  4854 translations) resulting from the given syntax specification, which is
  4855 interpreted in the same manner as for the 'syntax' command.
  4856 
  4857 * 'Advanced' translation functions (parse_translation etc.) may depend
  4858 on the signature of the theory context being presently used for
  4859 parsing/printing, see also isar-ref manual.
  4860 
  4861 * Improved 'oracle' command provides a type-safe interface to turn an
  4862 ML expression of type theory -> T -> term into a primitive rule of
  4863 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4864 is already included here); see also FOL/ex/IffExample.thy;
  4865 INCOMPATIBILITY.
  4866 
  4867 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4868 before); "cI" is no longer bound, use "c.intro" instead.
  4869 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4870 axclasses vs. locales.
  4871 
  4872 * Improved internal renaming of symbolic identifiers -- attach primes
  4873 instead of base 26 numbers.
  4874 
  4875 * New flag show_question_marks controls printing of leading question
  4876 marks in schematic variable names.
  4877 
  4878 * In schematic variable names, *any* symbol following \<^isub> or
  4879 \<^isup> is now treated as part of the base name.  For example, the
  4880 following works without printing of awkward ".0" indexes:
  4881 
  4882   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4883     by simp
  4884 
  4885 * Inner syntax includes (*(*nested*) comments*).
  4886 
  4887 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4888 annotations as "(00...)".
  4889 
  4890 * Clear separation of logical types and nonterminals, where the latter
  4891 may only occur in 'syntax' specifications or type abbreviations.
  4892 Before that distinction was only partially implemented via type class
  4893 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4894 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4895 exotic syntax specifications may require further adaption
  4896 (e.g. Cube/Cube.thy).
  4897 
  4898 * Removed obsolete type class "logic", use the top sort {} instead.
  4899 Note that non-logical types should be declared as 'nonterminals'
  4900 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4901 specifications.
  4902 
  4903 * Attributes 'induct' and 'cases': type or set names may now be
  4904 locally fixed variables as well.
  4905 
  4906 * Simplifier: can now control the depth to which conditional rewriting
  4907 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4908 Limit.
  4909 
  4910 * Simplifier: simplification procedures may now take the current
  4911 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4912 interface), which is very useful for calling the Simplifier
  4913 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4914 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4915 low-level mk_simproc no longer applies Logic.varify internally, to
  4916 allow for use in a context of fixed variables.
  4917 
  4918 * thin_tac now works even if the assumption being deleted contains !!
  4919 or ==>.  More generally, erule now works even if the major premise of
  4920 the elimination rule contains !! or ==>.
  4921 
  4922 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4923 
  4924 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4925 from Pure, which contains all common declarations already.  Both
  4926 theories are defined via plain Isabelle/Isar .thy files.
  4927 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4928 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4929 use isatool fixcpure to adapt your theory and ML sources.
  4930 
  4931 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4932 selections of theorems in named facts via index ranges.
  4933 
  4934 * 'print_theorems': in theory mode, really print the difference
  4935 wrt. the last state (works for interactive theory development only),
  4936 in proof mode print all local facts (cf. 'print_facts');
  4937 
  4938 * 'hide': option '(open)' hides only base names.
  4939 
  4940 * More efficient treatment of intermediate checkpoints in interactive
  4941 theory development.
  4942 
  4943 * Code generator is now invoked via code_module (incremental code
  4944 generation) and code_library (modular code generation, ML structures
  4945 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4946 must be quoted when used as identifiers.
  4947 
  4948 * New 'value' command for reading, evaluating and printing terms using
  4949 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4950 quoted when used as identifier.
  4951 
  4952 
  4953 *** Locales ***
  4954 
  4955 * New commands for the interpretation of locale expressions in
  4956 theories (1), locales (2) and proof contexts (3).  These generate
  4957 proof obligations from the expression specification.  After the
  4958 obligations have been discharged, theorems of the expression are added
  4959 to the theory, target locale or proof context.  The synopsis of the
  4960 commands is a follows:
  4961 
  4962   (1) interpretation expr inst
  4963   (2) interpretation target < expr
  4964   (3) interpret expr inst
  4965 
  4966 Interpretation in theories and proof contexts require a parameter
  4967 instantiation of terms from the current context.  This is applied to
  4968 specifications and theorems of the interpreted expression.
  4969 Interpretation in locales only permits parameter renaming through the
  4970 locale expression.  Interpretation is smart in that interpretations
  4971 that are active already do not occur in proof obligations, neither are
  4972 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4973 inspect active interpretations of a particular locale.  For details,
  4974 see the Isar Reference manual.  Examples can be found in
  4975 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4976 
  4977 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4978 'interpret' instead.
  4979 
  4980 * New context element 'constrains' for adding type constraints to
  4981 parameters.
  4982 
  4983 * Context expressions: renaming of parameters with syntax
  4984 redeclaration.
  4985 
  4986 * Locale declaration: 'includes' disallowed.
  4987 
  4988 * Proper static binding of attribute syntax -- i.e. types / terms /
  4989 facts mentioned as arguments are always those of the locale definition
  4990 context, independently of the context of later invocations.  Moreover,
  4991 locale operations (renaming and type / term instantiation) are applied
  4992 to attribute arguments as expected.
  4993 
  4994 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4995 actual attributes; rare situations may require Attrib.attribute to
  4996 embed those attributes into Attrib.src that lack concrete syntax.
  4997 Attribute implementations need to cooperate properly with the static
  4998 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4999 Attrib.XXX_thm etc. already do the right thing without further
  5000 intervention.  Only unusual applications -- such as "where" or "of"
  5001 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  5002 on the context and the facts involved -- may have to assign parsed
  5003 values to argument tokens explicitly.
  5004 
  5005 * Changed parameter management in theorem generation for long goal
  5006 statements with 'includes'.  INCOMPATIBILITY: produces a different
  5007 theorem statement in rare situations.
  5008 
  5009 * Locale inspection command 'print_locale' omits notes elements.  Use
  5010 'print_locale!' to have them included in the output.
  5011 
  5012 
  5013 *** Provers ***
  5014 
  5015 * Provers/hypsubst.ML: improved version of the subst method, for
  5016 single-step rewriting: it now works in bound variable contexts. New is
  5017 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  5018 rewrite a different subterm than the original subst method, which is
  5019 still available as 'simplesubst'.
  5020 
  5021 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  5022 and quasi orders.
  5023 
  5024 * Provers/trancl.ML: new transitivity reasoner for transitive and
  5025 reflexive-transitive closure of relations.
  5026 
  5027 * Provers/blast.ML: new reference depth_limit to make blast's depth
  5028 limit (previously hard-coded with a value of 20) user-definable.
  5029 
  5030 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  5031 is peformed already.  Object-logics merely need to finish their
  5032 initial simpset configuration as before.  INCOMPATIBILITY.
  5033 
  5034 
  5035 *** HOL ***
  5036 
  5037 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  5038 
  5039   syntax (epsilon)
  5040     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  5041 
  5042 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  5043 and x-symbol; use option '-m epsilon' to get it actually printed.
  5044 Moreover, the mathematically important symbolic identifier \<epsilon>
  5045 becomes available as variable, constant etc.  INCOMPATIBILITY,
  5046 
  5047 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  5048 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  5049 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  5050 support corresponding Isar calculations.
  5051 
  5052 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  5053 instead of ":".
  5054 
  5055 * theory SetInterval: changed the syntax for open intervals:
  5056 
  5057   Old       New
  5058   {..n(}    {..<n}
  5059   {)n..}    {n<..}
  5060   {m..n(}   {m..<n}
  5061   {)m..n}   {m<..n}
  5062   {)m..n(}  {m<..<n}
  5063 
  5064 The old syntax is still supported but will disappear in the next
  5065 release.  For conversion use the following Emacs search and replace
  5066 patterns (these are not perfect but work quite well):
  5067 
  5068   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  5069   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  5070 
  5071 * Theory Commutative_Ring (in Library): method comm_ring for proving
  5072 equalities in commutative rings; method 'algebra' provides a generic
  5073 interface.
  5074 
  5075 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  5076 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  5077 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  5078 be a tuple pattern.
  5079 
  5080 Some new syntax forms are available:
  5081 
  5082   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  5083   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  5084   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  5085   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  5086 
  5087 The latter form "\<Sum>x < k. e" used to be based on a separate
  5088 function "Summation", which has been discontinued.
  5089 
  5090 * theory Finite_Set: in structured induction proofs, the insert case
  5091 is now 'case (insert x F)' instead of the old counterintuitive 'case
  5092 (insert F x)'.
  5093 
  5094 * The 'refute' command has been extended to support a much larger
  5095 fragment of HOL, including axiomatic type classes, constdefs and
  5096 typedefs, inductive datatypes and recursion.
  5097 
  5098 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  5099 Requires zChaff with proof generation to be installed.  See
  5100 HOL/ex/SAT_Examples.thy for examples.
  5101 
  5102 * Datatype induction via method 'induct' now preserves the name of the
  5103 induction variable. For example, when proving P(xs::'a list) by
  5104 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  5105 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  5106 in unstructured proof scripts.
  5107 
  5108 * Reworked implementation of records.  Improved scalability for
  5109 records with many fields, avoiding performance problems for type
  5110 inference. Records are no longer composed of nested field types, but
  5111 of nested extension types. Therefore the record type only grows linear
  5112 in the number of extensions and not in the number of fields.  The
  5113 top-level (users) view on records is preserved.  Potential
  5114 INCOMPATIBILITY only in strange cases, where the theory depends on the
  5115 old record representation. The type generated for a record is called
  5116 <record_name>_ext_type.
  5117 
  5118 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  5119 proofs triggered by a record definition or a simproc (if
  5120 quick_and_dirty is enabled).  Definitions of large records can take
  5121 quite long.
  5122 
  5123 New simproc record_upd_simproc for simplification of multiple record
  5124 updates enabled by default.  Moreover, trivial updates are also
  5125 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  5126 occasionally, since simplification is more powerful by default.
  5127 
  5128 * typedef: proper support for polymorphic sets, which contain extra
  5129 type-variables in the term.
  5130 
  5131 * Simplifier: automatically reasons about transitivity chains
  5132 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  5133 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  5134 old proofs break occasionally as simplification may now solve more
  5135 goals than previously.
  5136 
  5137 * Simplifier: converts x <= y into x = y if assumption y <= x is
  5138 present.  Works for all partial orders (class "order"), in particular
  5139 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  5140 just like y <= x.
  5141 
  5142 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  5143 bound variable or a constant then the let is unfolded.  Otherwise
  5144 first a is simplified to b, and then f b is simplified to g. If
  5145 possible we abstract b from g arriving at "let x = b in h x",
  5146 otherwise we unfold the let and arrive at g.  The simproc can be
  5147 enabled/disabled by the reference use_let_simproc.  Potential
  5148 INCOMPATIBILITY since simplification is more powerful by default.
  5149 
  5150 * Classical reasoning: the meson method now accepts theorems as arguments.
  5151 
  5152 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  5153 jobs to provide advice on the provability of subgoals.
  5154 
  5155 * Theory OrderedGroup and Ring_and_Field: various additions and
  5156 improvements to faciliate calculations involving equalities and
  5157 inequalities.
  5158 
  5159 The following theorems have been eliminated or modified
  5160 (INCOMPATIBILITY):
  5161 
  5162   abs_eq             now named abs_of_nonneg
  5163   abs_of_ge_0        now named abs_of_nonneg
  5164   abs_minus_eq       now named abs_of_nonpos
  5165   imp_abs_id         now named abs_of_nonneg
  5166   imp_abs_neg_id     now named abs_of_nonpos
  5167   mult_pos           now named mult_pos_pos
  5168   mult_pos_le        now named mult_nonneg_nonneg
  5169   mult_pos_neg_le    now named mult_nonneg_nonpos
  5170   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5171   mult_neg           now named mult_neg_neg
  5172   mult_neg_le        now named mult_nonpos_nonpos
  5173 
  5174 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5175      
  5176      zero_le_square
  5177      not_square_less_zero 
  5178 
  5179   The following lemmas have been deleted from Real/RealPow:
  5180   
  5181      realpow_zero_zero
  5182      realpow_two
  5183      realpow_less
  5184      zero_le_power
  5185      realpow_two_le
  5186      abs_realpow_two
  5187      realpow_two_abs     
  5188 
  5189 * Theory Parity: added rules for simplifying exponents.
  5190 
  5191 * Theory List:
  5192 
  5193 The following theorems have been eliminated or modified
  5194 (INCOMPATIBILITY):
  5195 
  5196   list_all_Nil       now named list_all.simps(1)
  5197   list_all_Cons      now named list_all.simps(2)
  5198   list_all_conv      now named list_all_iff
  5199   set_mem_eq         now named mem_iff
  5200 
  5201 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5202 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5203 
  5204 
  5205 *** HOL-Complex ***
  5206 
  5207 * Theory RealDef: better support for embedding natural numbers and
  5208 integers in the reals.
  5209 
  5210 The following theorems have been eliminated or modified
  5211 (INCOMPATIBILITY):
  5212 
  5213   exp_ge_add_one_self  now requires no hypotheses
  5214   real_of_int_add      reversed direction of equality (use [symmetric])
  5215   real_of_int_minus    reversed direction of equality (use [symmetric])
  5216   real_of_int_diff     reversed direction of equality (use [symmetric])
  5217   real_of_int_mult     reversed direction of equality (use [symmetric])
  5218 
  5219 * Theory RComplete: expanded support for floor and ceiling functions.
  5220 
  5221 * Theory Ln is new, with properties of the natural logarithm
  5222 
  5223 * Hyperreal: There is a new type constructor "star" for making
  5224 nonstandard types.  The old type names are now type synonyms:
  5225 
  5226   hypreal = real star
  5227   hypnat = nat star
  5228   hcomplex = complex star
  5229 
  5230 * Hyperreal: Many groups of similarly-defined constants have been
  5231 replaced by polymorphic versions (INCOMPATIBILITY):
  5232 
  5233   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5234 
  5235   starset      <-- starsetNat, starsetC
  5236   *s*          <-- *sNat*, *sc*
  5237   starset_n    <-- starsetNat_n, starsetC_n
  5238   *sn*         <-- *sNatn*, *scn*
  5239   InternalSets <-- InternalNatSets, InternalCSets
  5240 
  5241   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5242   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5243   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5244   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5245   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5246 
  5247 * Hyperreal: Many type-specific theorems have been removed in favor of
  5248 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5249 
  5250   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5251   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5252   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5253   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5254   right_minus <-- hypreal_add_minus
  5255   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5256   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5257   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5258   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5259   mult_1_right <-- hcomplex_mult_one_right
  5260   mult_zero_left <-- hcomplex_mult_zero_left
  5261   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5262   right_distrib <-- hypnat_add_mult_distrib2
  5263   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5264   right_inverse <-- hypreal_mult_inverse
  5265   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5266   order_refl <-- {hypreal,hypnat}_le_refl
  5267   order_trans <-- {hypreal,hypnat}_le_trans
  5268   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5269   order_less_le <-- {hypreal,hypnat}_less_le
  5270   linorder_linear <-- {hypreal,hypnat}_le_linear
  5271   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5272   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5273   add_nonneg_nonneg <-- hypreal_le_add_order
  5274 
  5275 * Hyperreal: Separate theorems having to do with type-specific
  5276 versions of constants have been merged into theorems that apply to the
  5277 new polymorphic constants (INCOMPATIBILITY):
  5278 
  5279   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5280   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5281   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5282   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5283   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5284   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5285   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5286   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5287   STAR_diff <-- {STAR,STARC}_diff
  5288   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5289     STARC_hcomplex_of_complex}_image_subset
  5290   starset_n_Un <-- starset{Nat,C}_n_Un
  5291   starset_n_Int <-- starset{Nat,C}_n_Int
  5292   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5293   starset_n_diff <-- starset{Nat,C}_n_diff
  5294   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5295   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5296   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5297   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5298   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5299   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5300   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5301   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5302   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5303   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5304   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5305   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5306   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5307   starfun_diff <-- starfun{C,RC,CR}_diff
  5308   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5309   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5310   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5311   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5312   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5313   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5314   starfun_Id <-- starfunC_Id
  5315   starfun_approx <-- starfun{Nat,CR}_approx
  5316   starfun_capprox <-- starfun{C,RC}_capprox
  5317   starfun_abs <-- starfunNat_rabs
  5318   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5319   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5320   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5321   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5322   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5323   starfun_add_approx <-- starfunCR_add_approx
  5324   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5325   starfun_divide <-- starfun{C,CR,RC}_divide
  5326   starfun_n <-- starfun{Nat,C}_n
  5327   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5328   starfun_n_add <-- starfun{Nat,C}_n_add
  5329   starfun_n_add_minus <-- starfunNat_n_add_minus
  5330   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5331   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5332   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5333 
  5334   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5335   star_n_minus <-- {hypreal,hcomplex}_minus
  5336   star_n_diff <-- {hypreal,hcomplex}_diff
  5337   star_n_mult <-- {hypreal,hcomplex}_mult
  5338   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5339   star_n_le <-- {hypreal,hypnat}_le
  5340   star_n_less <-- {hypreal,hypnat}_less
  5341   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5342   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5343   star_n_abs <-- hypreal_hrabs
  5344   star_n_divide <-- hcomplex_divide
  5345 
  5346   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5347   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5348   star_of_diff <-- hypreal_of_real_diff
  5349   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5350   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5351   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5352   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5353   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5354   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5355   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5356   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5357   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5358   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5359   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5360   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5361   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5362   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5363   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5364   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5365   star_of_power <-- hypreal_of_real_power
  5366   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5367 
  5368 * Hyperreal: new method "transfer" that implements the transfer
  5369 principle of nonstandard analysis. With a subgoal that mentions
  5370 nonstandard types like "'a star", the command "apply transfer"
  5371 replaces it with an equivalent one that mentions only standard types.
  5372 To be successful, all free variables must have standard types; non-
  5373 standard variables must have explicit universal quantifiers.
  5374 
  5375 * Hyperreal: A theory of Taylor series.
  5376 
  5377 
  5378 *** HOLCF ***
  5379 
  5380 * Discontinued special version of 'constdefs' (which used to support
  5381 continuous functions) in favor of the general Pure one with full
  5382 type-inference.
  5383 
  5384 * New simplification procedure for solving continuity conditions; it
  5385 is much faster on terms with many nested lambda abstractions (cubic
  5386 instead of exponential time).
  5387 
  5388 * New syntax for domain package: selector names are now optional.
  5389 Parentheses should be omitted unless argument is lazy, for example:
  5390 
  5391   domain 'a stream = cons "'a" (lazy "'a stream")
  5392 
  5393 * New command 'fixrec' for defining recursive functions with pattern
  5394 matching; defining multiple functions with mutual recursion is also
  5395 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5396 sinr, or any data constructor defined by the domain package. The given
  5397 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5398 syntax and examples.
  5399 
  5400 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5401 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5402 but the proof obligation additionally includes an admissibility
  5403 requirement. The packages generate instances of class cpo or pcpo,
  5404 with continuity and strictness theorems for Rep and Abs.
  5405 
  5406 * HOLCF: Many theorems have been renamed according to a more standard naming
  5407 scheme (INCOMPATIBILITY):
  5408 
  5409   foo_inject:  "foo$x = foo$y ==> x = y"
  5410   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5411   foo_less:    "(foo$x << foo$y) = (x << y)"
  5412   foo_strict:  "foo$UU = UU"
  5413   foo_defined: "... ==> foo$x ~= UU"
  5414   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5415 
  5416 
  5417 *** ZF ***
  5418 
  5419 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5420 including the First Isomorphism Theorem (on quotienting by the kernel
  5421 of a homomorphism).
  5422 
  5423 * ZF/Simplifier: install second copy of type solver that actually
  5424 makes use of TC rules declared to Isar proof contexts (or locales);
  5425 the old version is still required for ML proof scripts.
  5426 
  5427 
  5428 *** Cube ***
  5429 
  5430 * Converted to Isar theory format; use locales instead of axiomatic
  5431 theories.
  5432 
  5433 
  5434 *** ML ***
  5435 
  5436 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5437 for ||>, ||>>, |>>,
  5438 
  5439 * Pure/library.ML no longer defines its own option datatype, but uses
  5440 that of the SML basis, which has constructors NONE and SOME instead of
  5441 None and Some, as well as exception Option.Option instead of OPTION.
  5442 The functions the, if_none, is_some, is_none have been adapted
  5443 accordingly, while Option.map replaces apsome.
  5444 
  5445 * Pure/library.ML: the exception LIST has been given up in favour of
  5446 the standard exceptions Empty and Subscript, as well as
  5447 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5448 superceded by the standard hd and tl functions etc.
  5449 
  5450 A number of basic list functions are no longer exported to the ML
  5451 toplevel, as they are variants of predefined functions.  The following
  5452 suggests how one can translate existing code:
  5453 
  5454     rev_append xs ys = List.revAppend (xs, ys)
  5455     nth_elem (i, xs) = List.nth (xs, i)
  5456     last_elem xs = List.last xs
  5457     flat xss = List.concat xss
  5458     seq fs = List.app fs
  5459     partition P xs = List.partition P xs
  5460     mapfilter f xs = List.mapPartial f xs
  5461 
  5462 * Pure/library.ML: several combinators for linear functional
  5463 transformations, notably reverse application and composition:
  5464 
  5465   x |> f                f #> g
  5466   (x, y) |-> f          f #-> g
  5467 
  5468 * Pure/library.ML: introduced/changed precedence of infix operators:
  5469 
  5470   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5471   infix 2 ?;
  5472   infix 3 o oo ooo oooo;
  5473   infix 4 ~~ upto downto;
  5474 
  5475 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5476 infix operators.
  5477 
  5478 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5479 fold_map support linear functional transformations and nesting.  For
  5480 example:
  5481 
  5482   fold f [x1, ..., xN] y =
  5483     y |> f x1 |> ... |> f xN
  5484 
  5485   (fold o fold) f [xs1, ..., xsN] y =
  5486     y |> fold f xs1 |> ... |> fold f xsN
  5487 
  5488   fold f [x1, ..., xN] =
  5489     f x1 #> ... #> f xN
  5490 
  5491   (fold o fold) f [xs1, ..., xsN] =
  5492     fold f xs1 #> ... #> fold f xsN
  5493 
  5494 * Pure/library.ML: the following selectors on type 'a option are
  5495 available:
  5496 
  5497   the:               'a option -> 'a  (*partial*)
  5498   these:             'a option -> 'a  where 'a = 'b list
  5499   the_default: 'a -> 'a option -> 'a
  5500   the_list:          'a option -> 'a list
  5501 
  5502 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5503 basic operations for association lists, following natural argument
  5504 order; moreover the explicit equality predicate passed here avoids
  5505 potentially expensive polymorphic runtime equality checks.
  5506 The old functions may be expressed as follows:
  5507 
  5508   assoc = uncurry (AList.lookup (op =))
  5509   assocs = these oo AList.lookup (op =)
  5510   overwrite = uncurry (AList.update (op =)) o swap
  5511 
  5512 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5513 
  5514   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5515   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5516 
  5517 replacing make_keylist and keyfilter (occassionally used)
  5518 Naive rewrites:
  5519 
  5520   make_keylist = AList.make
  5521   keyfilter = AList.find (op =)
  5522 
  5523 * eq_fst and eq_snd now take explicit equality parameter, thus
  5524   avoiding eqtypes. Naive rewrites:
  5525 
  5526     eq_fst = eq_fst (op =)
  5527     eq_snd = eq_snd (op =)
  5528 
  5529 * Removed deprecated apl and apr (rarely used).
  5530   Naive rewrites:
  5531 
  5532     apl (n, op) =>>= curry op n
  5533     apr (op, m) =>>= fn n => op (n, m)
  5534 
  5535 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5536 provides a reasonably efficient light-weight implementation of sets as
  5537 lists.
  5538 
  5539 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5540 few new operations; existing lookup and update are now curried to
  5541 follow natural argument order (for use with fold etc.);
  5542 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5543 
  5544 * Pure/General: output via the Isabelle channels of
  5545 writeln/warning/error etc. is now passed through Output.output, with a
  5546 hook for arbitrary transformations depending on the print_mode
  5547 (cf. Output.add_mode -- the first active mode that provides a output
  5548 function wins).  Already formatted output may be embedded into further
  5549 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5550 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5551 accommodate easy composition of diagnostic messages etc.  Programmers
  5552 rarely need to care about Output.output or Output.raw at all, with
  5553 some notable exceptions: Output.output is required when bypassing the
  5554 standard channels (writeln etc.), or in token translations to produce
  5555 properly formatted results; Output.raw is required when capturing
  5556 already output material that will eventually be presented to the user
  5557 a second time.  For the default print mode, both Output.output and
  5558 Output.raw have no effect.
  5559 
  5560 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5561 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5562 cumulative results are displayed at the end of a batch session.
  5563 
  5564 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5565 replaced by File.platform_path and File.shell_path (with appropriate
  5566 hooks).  This provides a clean interface for unusual systems where the
  5567 internal and external process view of file names are different.
  5568 
  5569 * Pure: more efficient orders for basic syntactic entities: added
  5570 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5571 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5572 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5573 orders now -- potential INCOMPATIBILITY for code that depends on a
  5574 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5575 Library.sort_strings on result).
  5576 
  5577 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5578 fold_types traverse types/terms from left to right, observing natural
  5579 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5580 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5581 
  5582 * Pure: name spaces have been refined, with significant changes of the
  5583 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5584 to extern(_table).  The plain name entry path is superceded by a
  5585 general 'naming' context, which also includes the 'policy' to produce
  5586 a fully qualified name and external accesses of a fully qualified
  5587 name; NameSpace.extend is superceded by context dependent
  5588 Sign.declare_name.  Several theory and proof context operations modify
  5589 the naming context.  Especially note Theory.restore_naming and
  5590 ProofContext.restore_naming to get back to a sane state; note that
  5591 Theory.add_path is no longer sufficient to recover from
  5592 Theory.absolute_path in particular.
  5593 
  5594 * Pure: new flags short_names (default false) and unique_names
  5595 (default true) for controlling output of qualified names.  If
  5596 short_names is set, names are printed unqualified.  If unique_names is
  5597 reset, the name prefix is reduced to the minimum required to achieve
  5598 the original result when interning again, even if there is an overlap
  5599 with earlier declarations.
  5600 
  5601 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5602 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5603 (useful for printing error messages).  INCOMPATIBILITY.
  5604 
  5605 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5606 Theory.theory are now identified, referring to the universal
  5607 Context.theory (see Pure/context.ML).  Actual signature and theory
  5608 content is managed as theory data.  The old code and interfaces were
  5609 spread over many files and structures; the new arrangement introduces
  5610 considerable INCOMPATIBILITY to gain more clarity:
  5611 
  5612   Context -- theory management operations (name, identity, inclusion,
  5613     parents, ancestors, merge, etc.), plus generic theory data;
  5614 
  5615   Sign -- logical signature and syntax operations (declaring consts,
  5616     types, etc.), plus certify/read for common entities;
  5617 
  5618   Theory -- logical theory operations (stating axioms, definitions,
  5619     oracles), plus a copy of logical signature operations (consts,
  5620     types, etc.); also a few basic management operations (Theory.copy,
  5621     Theory.merge, etc.)
  5622 
  5623 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5624 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5625 for convenience -- they merely return the theory.
  5626 
  5627 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5628 
  5629 * Pure: the Isar proof context type is already defined early in Pure
  5630 as Context.proof (note that ProofContext.context and Proof.context are
  5631 aliases, where the latter is the preferred name).  This enables other
  5632 Isabelle components to refer to that type even before Isar is present.
  5633 
  5634 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5635 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5636 any of these kinds.  For example, Sign.intern typeK is now
  5637 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5638 Theory.hide_types.  Also note that former
  5639 Theory.hide_classes/types/consts are now
  5640 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5641 internalize their arguments!  INCOMPATIBILITY.
  5642 
  5643 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5644 datatype thmref (with constructors Name and NameSelection) instead of
  5645 plain string -- INCOMPATIBILITY;
  5646 
  5647 * Pure: cases produced by proof methods specify options, where NONE
  5648 means to remove case bindings -- INCOMPATIBILITY in
  5649 (RAW_)METHOD_CASES.
  5650 
  5651 * Pure: the following operations retrieve axioms or theorems from a
  5652 theory node or theory hierarchy, respectively:
  5653 
  5654   Theory.axioms_of: theory -> (string * term) list
  5655   Theory.all_axioms_of: theory -> (string * term) list
  5656   PureThy.thms_of: theory -> (string * thm) list
  5657   PureThy.all_thms_of: theory -> (string * thm) list
  5658 
  5659 * Pure: print_tac now outputs the goal through the trace channel.
  5660 
  5661 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5662 Reference Toplevel.debug (default false) controls detailed printing
  5663 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5664 controls execution profiling -- set to 1 for time and 2 for space
  5665 (both increase the runtime).
  5666 
  5667 * Isar session: The initial use of ROOT.ML is now always timed,
  5668 i.e. the log will show the actual process times, in contrast to the
  5669 elapsed wall-clock time that the outer shell wrapper produces.
  5670 
  5671 * Simplifier: improved handling of bound variables (nameless
  5672 representation, avoid allocating new strings).  Simprocs that invoke
  5673 the Simplifier recursively should use Simplifier.inherit_bounds to
  5674 avoid local name clashes.  Failure to do so produces warnings
  5675 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5676 for further details.
  5677 
  5678 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5679 bindings for all theorems stored within a given theory; this may help
  5680 in porting non-Isar theories to Isar ones, while keeping ML proof
  5681 scripts for the time being.
  5682 
  5683 * ML operator HTML.with_charset specifies the charset begin used for
  5684 generated HTML files.  For example:
  5685 
  5686   HTML.with_charset "utf-8" use_thy "Hebrew";
  5687   HTML.with_charset "utf-8" use_thy "Chinese";
  5688 
  5689 
  5690 *** System ***
  5691 
  5692 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5693 isabelle, isatool etc.).
  5694 
  5695 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5696 isatool doc, isatool mkdir, display_drafts etc.).
  5697 
  5698 * isatool usedir: option -f allows specification of the ML file to be
  5699 used by Isabelle; default is ROOT.ML.
  5700 
  5701 * New isatool version outputs the version identifier of the Isabelle
  5702 distribution being used.
  5703 
  5704 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5705 (containing Boolean satisfiability problems) into Isabelle/HOL
  5706 theories.
  5707 
  5708 
  5709 
  5710 New in Isabelle2004 (April 2004)
  5711 --------------------------------
  5712 
  5713 *** General ***
  5714 
  5715 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5716   Replaces linorder.ML.
  5717 
  5718 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5719   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5720   (\<a>...\<z>), are now considered normal letters, and can therefore
  5721   be used anywhere where an ASCII letter (a...zA...Z) has until
  5722   now. COMPATIBILITY: This obviously changes the parsing of some
  5723   terms, especially where a symbol has been used as a binder, say
  5724   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5725   as an identifier.  Fix it by inserting a space around former
  5726   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5727   existing theory and ML files.
  5728 
  5729 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5730 
  5731 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5732   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5733   a normal (but invisible) letter. For multiple letter subscripts repeat
  5734   \<^isub> like this: x\<^isub>1\<^isub>2.
  5735 
  5736 * Pure: There are now sub-/superscripts that can span more than one
  5737   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5738   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5739   superscript. The new control characters are not identifier parts.
  5740 
  5741 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5742   content of "..." to the latex file instead of \isacntrl... . The "..."
  5743   may consist of any printable characters excluding the end bracket >.
  5744 
  5745 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5746   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5747   declare constants "final", which prevents their being given a definition
  5748   later.  It is useful for constants whose behaviour is fixed axiomatically
  5749   rather than definitionally, such as the meta-logic connectives.
  5750 
  5751 * Pure: 'instance' now handles general arities with general sorts
  5752   (i.e. intersections of classes),
  5753 
  5754 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5755   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5756   It can be changed to alter the colors/layout of generated pages.
  5757 
  5758 
  5759 *** Isar ***
  5760 
  5761 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5762   cut_tac, subgoal_tac and thin_tac:
  5763   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5764     locales are no longer forced to write Isar proof scripts.
  5765     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5766     emulations.
  5767   - INCOMPATIBILITY: names of variables to be instantiated may no
  5768     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5769     This is consistent with the instantiation attribute "where".
  5770 
  5771 * Attributes "where" and "of":
  5772   - Now take type variables of instantiated theorem into account when reading
  5773     the instantiation string.  This fixes a bug that caused instantiated
  5774     theorems to have too special types in some circumstances.
  5775   - "where" permits explicit instantiations of type variables.
  5776 
  5777 * Calculation commands "moreover" and "also" no longer interfere with
  5778   current facts ("this"), admitting arbitrary combinations with "then"
  5779   and derived forms.
  5780 
  5781 * Locales:
  5782   - Goal statements involving the context element "includes" no longer
  5783     generate theorems with internal delta predicates (those ending on
  5784     "_axioms") in the premise.
  5785     Resolve particular premise with <locale>.intro to obtain old form.
  5786   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5787     specification and "includes" elements in goal statement.
  5788   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5789     [intro?] and [elim?] (respectively) by default.
  5790   - Experimental command for instantiation of locales in proof contexts:
  5791         instantiate <label>[<attrs>]: <loc>
  5792     Instantiates locale <loc> and adds all its theorems to the current context
  5793     taking into account their attributes.  Label and attrs are optional
  5794     modifiers, like in theorem declarations.  If present, names of
  5795     instantiated theorems are qualified with <label>, and the attributes
  5796     <attrs> are applied after any attributes these theorems might have already.
  5797       If the locale has assumptions, a chained fact of the form
  5798     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5799     are derived.  The command does not support old-style locales declared
  5800     with "locale (open)".
  5801       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5802 
  5803 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5804   (Isar) contexts.
  5805 
  5806 
  5807 *** HOL ***
  5808 
  5809 * Proof import: new image HOL4 contains the imported library from
  5810   the HOL4 system with about 2500 theorems. It is imported by
  5811   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5812   can be used like any other Isabelle image.  See
  5813   HOL/Import/HOL/README for more information.
  5814 
  5815 * Simplifier:
  5816   - Much improved handling of linear and partial orders.
  5817     Reasoners for linear and partial orders are set up for type classes
  5818     "linorder" and "order" respectively, and are added to the default simpset
  5819     as solvers.  This means that the simplifier can build transitivity chains
  5820     to solve goals from the assumptions.
  5821   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5822     of blast or auto after simplification become unnecessary because the goal
  5823     is solved by simplification already.
  5824 
  5825 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5826     all proved in axiomatic type classes for semirings, rings and fields.
  5827 
  5828 * Numerics:
  5829   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5830     now formalized using the Ring_and_Field theory mentioned above.
  5831   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5832     than before, because now they are set up once in a generic manner.
  5833   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5834     Look for the general versions in Ring_and_Field (and Power if they concern
  5835     exponentiation).
  5836 
  5837 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5838 
  5839 * Records:
  5840   - Record types are now by default printed with their type abbreviation
  5841     instead of the list of all field types. This can be configured via
  5842     the reference "print_record_type_abbr".
  5843   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5844     (not enabled by default).
  5845   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5846     EX x. x = sel r to True (not enabled by default).
  5847   - Tactic "record_split_simp_tac" to split and simplify records added.
  5848 
  5849 * 'specification' command added, allowing for definition by
  5850   specification.  There is also an 'ax_specification' command that
  5851   introduces the new constants axiomatically.
  5852 
  5853 * arith(_tac) is now able to generate counterexamples for reals as well.
  5854 
  5855 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5856 
  5857 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5858   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5859 
  5860 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5861   matrix theory to linear programming.
  5862 
  5863 * Unions and Intersections:
  5864   The latex output syntax of UN and INT has been changed
  5865   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5866   i.e. the index formulae has become a subscript.
  5867   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5868 
  5869 * Unions and Intersections over Intervals:
  5870   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5871   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5872   like in normal math, and corresponding versions for < and for intersection.
  5873 
  5874 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5875   lexicographic dictonary ordering has been added as "lexord".
  5876 
  5877 * ML: the legacy theory structures Int and List have been removed. They had
  5878   conflicted with ML Basis Library structures having the same names.
  5879 
  5880 * 'refute' command added to search for (finite) countermodels.  Only works
  5881   for a fragment of HOL.  The installation of an external SAT solver is
  5882   highly recommended.  See "HOL/Refute.thy" for details.
  5883 
  5884 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5885   formulae under an assignment of free variables to random values.
  5886   In contrast to 'refute', it can deal with inductive datatypes,
  5887   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5888   for examples.
  5889 
  5890 
  5891 *** HOLCF ***
  5892 
  5893 * Streams now come with concatenation and are part of the HOLCF image
  5894 
  5895 
  5896 
  5897 New in Isabelle2003 (May 2003)
  5898 ------------------------------
  5899 
  5900 *** General ***
  5901 
  5902 * Provers/simplifier:
  5903 
  5904   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5905     Assumptions are now subject to complete mutual simplification,
  5906     not just from left to right. The simplifier now preserves
  5907     the order of assumptions.
  5908 
  5909     Potential INCOMPATIBILITY:
  5910 
  5911     -- simp sometimes diverges where the old version did
  5912        not, e.g. invoking simp on the goal
  5913 
  5914         [| P (f x); y = x; f x = f y |] ==> Q
  5915 
  5916        now gives rise to the infinite reduction sequence
  5917 
  5918         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5919 
  5920        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5921        kind of problem.
  5922 
  5923     -- Tactics combining classical reasoner and simplification (such as auto)
  5924        are also affected by this change, because many of them rely on
  5925        simp. They may sometimes diverge as well or yield a different numbers
  5926        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5927        in case of problems. Sometimes subsequent calls to the classical
  5928        reasoner will fail because a preceeding call to the simplifier too
  5929        eagerly simplified the goal, e.g. deleted redundant premises.
  5930 
  5931   - The simplifier trace now shows the names of the applied rewrite rules
  5932 
  5933   - You can limit the number of recursive invocations of the simplifier
  5934     during conditional rewriting (where the simplifie tries to solve the
  5935     conditions before applying the rewrite rule):
  5936     ML "simp_depth_limit := n"
  5937     where n is an integer. Thus you can force termination where previously
  5938     the simplifier would diverge.
  5939 
  5940   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5941 
  5942   - No longer aborts on failed congruence proof.  Instead, the
  5943     congruence is ignored.
  5944 
  5945 * Pure: New generic framework for extracting programs from constructive
  5946   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5947   as HOL/Extraction for some case studies.
  5948 
  5949 * Pure: The main goal of the proof state is no longer shown by default, only
  5950 the subgoals. This behaviour is controlled by a new flag.
  5951    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5952 (ML: Proof.show_main_goal).
  5953 
  5954 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5955 rules whose conclusion matches subgoal 1:
  5956       PG menu: Isabelle/Isar -> Show me -> matching rules
  5957 The rules are ordered by how closely they match the subgoal.
  5958 In particular, rules that solve a subgoal outright are displayed first
  5959 (or rather last, the way they are printed).
  5960 (ML: ProofGeneral.print_intros())
  5961 
  5962 * Pure: New flag trace_unify_fail causes unification to print
  5963 diagnostic information (PG: in trace buffer) when it fails. This is
  5964 useful for figuring out why single step proofs like rule, erule or
  5965 assumption failed.
  5966 
  5967 * Pure: Locale specifications now produce predicate definitions
  5968 according to the body of text (covering assumptions modulo local
  5969 definitions); predicate "loc_axioms" covers newly introduced text,
  5970 while "loc" is cumulative wrt. all included locale expressions; the
  5971 latter view is presented only on export into the global theory
  5972 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5973 on the old view without predicates;
  5974 
  5975 * Pure: predefined locales "var" and "struct" are useful for sharing
  5976 parameters (as in CASL, for example); just specify something like
  5977 ``var x + var y + struct M'' as import;
  5978 
  5979 * Pure: improved thms_containing: proper indexing of facts instead of
  5980 raw theorems; check validity of results wrt. current name space;
  5981 include local facts of proof configuration (also covers active
  5982 locales), cover fixed variables in index; may use "_" in term
  5983 specification; an optional limit for the number of printed facts may
  5984 be given (the default is 40);
  5985 
  5986 * Pure: disallow duplicate fact bindings within new-style theory files
  5987 (batch-mode only);
  5988 
  5989 * Provers: improved induct method: assumptions introduced by case
  5990 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5991 the goal statement); "foo" still refers to all facts collectively;
  5992 
  5993 * Provers: the function blast.overloaded has been removed: all constants
  5994 are regarded as potentially overloaded, which improves robustness in exchange
  5995 for slight decrease in efficiency;
  5996 
  5997 * Provers/linorder: New generic prover for transitivity reasoning over
  5998 linear orders.  Note: this prover is not efficient!
  5999 
  6000 * Isar: preview of problems to finish 'show' now produce an error
  6001 rather than just a warning (in interactive mode);
  6002 
  6003 
  6004 *** HOL ***
  6005 
  6006 * arith(_tac)
  6007 
  6008  - Produces a counter example if it cannot prove a goal.
  6009    Note that the counter example may be spurious if the goal is not a formula
  6010    of quantifier-free linear arithmetic.
  6011    In ProofGeneral the counter example appears in the trace buffer.
  6012 
  6013  - Knows about div k and mod k where k is a numeral of type nat or int.
  6014 
  6015  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  6016    linear arithmetic fails. This takes account of quantifiers and divisibility.
  6017    Presburger arithmetic can also be called explicitly via presburger(_tac).
  6018 
  6019 * simp's arithmetic capabilities have been enhanced a bit: it now
  6020 takes ~= in premises into account (by performing a case split);
  6021 
  6022 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  6023 are distributed over a sum of terms;
  6024 
  6025 * New tactic "trans_tac" and method "trans" instantiate
  6026 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  6027 "<=", "<" and "=").
  6028 
  6029 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  6030 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  6031 
  6032 * 'typedef' command has new option "open" to suppress the set
  6033 definition;
  6034 
  6035 * functions Min and Max on finite sets have been introduced (theory
  6036 Finite_Set);
  6037 
  6038 * attribute [symmetric] now works for relations as well; it turns
  6039 (x,y) : R^-1 into (y,x) : R, and vice versa;
  6040 
  6041 * induct over a !!-quantified statement (say !!x1..xn):
  6042   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  6043 
  6044 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  6045 %x. None. Warning: empty_def now refers to the previously hidden definition
  6046 of the empty set.
  6047 
  6048 * Algebra: formalization of classical algebra.  Intended as base for
  6049 any algebraic development in Isabelle.  Currently covers group theory
  6050 (up to Sylow's theorem) and ring theory (Universal Property of
  6051 Univariate Polynomials).  Contributions welcome;
  6052 
  6053 * GroupTheory: deleted, since its material has been moved to Algebra;
  6054 
  6055 * Complex: new directory of the complex numbers with numeric constants,
  6056 nonstandard complex numbers, and some complex analysis, standard and
  6057 nonstandard (Jacques Fleuriot);
  6058 
  6059 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  6060 
  6061 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  6062 Fleuriot);
  6063 
  6064 * Real/HahnBanach: updated and adapted to locales;
  6065 
  6066 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  6067 Gray and Kramer);
  6068 
  6069 * UNITY: added the Meier-Sanders theory of progress sets;
  6070 
  6071 * MicroJava: bytecode verifier and lightweight bytecode verifier
  6072 as abstract algorithms, instantiated to the JVM;
  6073 
  6074 * Bali: Java source language formalization. Type system, operational
  6075 semantics, axiomatic semantics. Supported language features:
  6076 classes, interfaces, objects,virtual methods, static methods,
  6077 static/instance fields, arrays, access modifiers, definite
  6078 assignment, exceptions.
  6079 
  6080 
  6081 *** ZF ***
  6082 
  6083 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  6084 universe, etc.);
  6085 
  6086 * Main ZF: virtually all theories converted to new-style format;
  6087 
  6088 
  6089 *** ML ***
  6090 
  6091 * Pure: Tactic.prove provides sane interface for internal proofs;
  6092 omits the infamous "standard" operation, so this is more appropriate
  6093 than prove_goalw_cterm in many situations (e.g. in simprocs);
  6094 
  6095 * Pure: improved error reporting of simprocs;
  6096 
  6097 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  6098 up simprocs;
  6099 
  6100 
  6101 *** Document preparation ***
  6102 
  6103 * uses \par instead of \\ for line breaks in theory text. This may
  6104 shift some page breaks in large documents. To get the old behaviour
  6105 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  6106 
  6107 * minimized dependencies of isabelle.sty and isabellesym.sty on
  6108 other packages
  6109 
  6110 * \<euro> now needs package babel/greek instead of marvosym (which
  6111 broke \Rightarrow)
  6112 
  6113 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  6114 textcomp package)
  6115 
  6116 
  6117 
  6118 New in Isabelle2002 (March 2002)
  6119 --------------------------------
  6120 
  6121 *** Document preparation ***
  6122 
  6123 * greatly simplified document preparation setup, including more
  6124 graceful interpretation of isatool usedir -i/-d/-D options, and more
  6125 instructive isatool mkdir; users should basically be able to get
  6126 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  6127 users may run a separate document processing stage manually like this:
  6128 "isatool usedir -D output HOL Test && isatool document Test/output";
  6129 
  6130 * theory dependency graph may now be incorporated into documents;
  6131 isatool usedir -g true will produce session_graph.eps/.pdf for use
  6132 with \includegraphics of LaTeX;
  6133 
  6134 * proper spacing of consecutive markup elements, especially text
  6135 blocks after section headings;
  6136 
  6137 * support bold style (for single symbols only), input syntax is like
  6138 this: "\<^bold>\<alpha>" or "\<^bold>A";
  6139 
  6140 * \<bullet> is now output as bold \cdot by default, which looks much
  6141 better in printed text;
  6142 
  6143 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  6144 note that these symbols are currently unavailable in Proof General /
  6145 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  6146 
  6147 * isatool latex no longer depends on changed TEXINPUTS, instead
  6148 isatool document copies the Isabelle style files to the target
  6149 location;
  6150 
  6151 
  6152 *** Isar ***
  6153 
  6154 * Pure/Provers: improved proof by cases and induction;
  6155   - 'case' command admits impromptu naming of parameters (such as
  6156     "case (Suc n)");
  6157   - 'induct' method divinates rule instantiation from the inductive
  6158     claim; no longer requires excessive ?P bindings for proper
  6159     instantiation of cases;
  6160   - 'induct' method properly enumerates all possibilities of set/type
  6161     rules; as a consequence facts may be also passed through *type*
  6162     rules without further ado;
  6163   - 'induct' method now derives symbolic cases from the *rulified*
  6164     rule (before it used to rulify cases stemming from the internal
  6165     atomized version); this means that the context of a non-atomic
  6166     statement becomes is included in the hypothesis, avoiding the
  6167     slightly cumbersome show "PROP ?case" form;
  6168   - 'induct' may now use elim-style induction rules without chaining
  6169     facts, using ``missing'' premises from the goal state; this allows
  6170     rules stemming from inductive sets to be applied in unstructured
  6171     scripts, while still benefitting from proper handling of non-atomic
  6172     statements; NB: major inductive premises need to be put first, all
  6173     the rest of the goal is passed through the induction;
  6174   - 'induct' proper support for mutual induction involving non-atomic
  6175     rule statements (uses the new concept of simultaneous goals, see
  6176     below);
  6177   - append all possible rule selections, but only use the first
  6178     success (no backtracking);
  6179   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  6180   - undeclared rule case names default to numbers 1, 2, 3, ...;
  6181   - added 'print_induct_rules' (covered by help item in recent Proof
  6182     General versions);
  6183   - moved induct/cases attributes to Pure, methods to Provers;
  6184   - generic method setup instantiated for FOL and HOL;
  6185 
  6186 * Pure: support multiple simultaneous goal statements, for example
  6187 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  6188 meta-level mechanism, this acts as if several individual goals had
  6189 been stated separately; in particular common proof methods need to be
  6190 repeated in order to cover all claims; note that a single elimination
  6191 step is *not* sufficient to establish the two conjunctions, so this
  6192 fails:
  6193 
  6194   assume "A & B" then have A and B ..   (*".." fails*)
  6195 
  6196 better use "obtain" in situations as above; alternative refer to
  6197 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  6198 
  6199 * Pure: proper integration with ``locales''; unlike the original
  6200 version by Florian Kammller, Isar locales package high-level proof
  6201 contexts rather than raw logical ones (e.g. we admit to include
  6202 attributes everywhere); operations on locales include merge and
  6203 rename; support for implicit arguments (``structures''); simultaneous
  6204 type-inference over imports and text; see also HOL/ex/Locales.thy for
  6205 some examples;
  6206 
  6207 * Pure: the following commands have been ``localized'', supporting a
  6208 target locale specification "(in name)": 'lemma', 'theorem',
  6209 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  6210 stored both within the locale and at the theory level (exported and
  6211 qualified by the locale name);
  6212 
  6213 * Pure: theory goals may now be specified in ``long'' form, with
  6214 ad-hoc contexts consisting of arbitrary locale elements. for example
  6215 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  6216 definitions may be given, too); the result is a meta-level rule with
  6217 the context elements being discharged in the obvious way;
  6218 
  6219 * Pure: new proof command 'using' allows to augment currently used
  6220 facts after a goal statement ('using' is syntactically analogous to
  6221 'apply', but acts on the goal's facts only); this allows chained facts
  6222 to be separated into parts given before and after a claim, as in
  6223 ``from a and b have C using d and e <proof>'';
  6224 
  6225 * Pure: renamed "antecedent" case to "rule_context";
  6226 
  6227 * Pure: new 'judgment' command records explicit information about the
  6228 object-logic embedding (used by several tools internally); no longer
  6229 use hard-wired "Trueprop";