NEWS
author bulwahn
Wed May 18 15:45:34 2011 +0200 (2011-05-18)
changeset 42843 0e594ba0b324
parent 42815 61668e617a3b
child 42874 f115492c7c8d
permissions -rw-r--r--
NEWS
     1 Isabelle NEWS -- history user-relevant changes
     2 ==============================================
     3 
     4 New in this Isabelle version
     5 ----------------------------
     6 
     7 *** General ***
     8 
     9 * Theory loader: source files are identified by content via SHA1
    10 digests.  Discontinued former path/modtime identification and optional
    11 ISABELLE_FILE_IDENT plugin scripts.
    12 
    13 * Parallelization of nested Isar proofs is subject to
    14 Goal.parallel_proofs_threshold (default 100).  See also isabelle
    15 usedir option -Q.
    16 
    17 * Discontinued support for Poly/ML 5.2, which was the last version
    18 without proper multithreading and TimeLimit implementation.
    19 
    20 * Discontinued old lib/scripts/polyml-platform, which has been
    21 obsolete since Isabelle2009-2.
    22 
    23 * Theory loader: source files are exclusively located via the master
    24 directory of each theory node (where the .thy file itself resides).
    25 The global load path (such as src/HOL/Library) is has been
    26 discontinued.  INCOMPATIBILITY.
    27 
    28 * Various optional external tools are referenced more robustly and
    29 uniformly by explicit Isabelle settings as follows:
    30 
    31   ISABELLE_CSDP   (formerly CSDP_EXE)
    32   ISABELLE_GHC    (formerly EXEC_GHC or GHC_PATH)
    33   ISABELLE_OCAML  (formerly EXEC_OCAML)
    34   ISABELLE_SWIPL  (formerly EXEC_SWIPL)
    35   ISABELLE_YAP    (formerly EXEC_YAP)
    36 
    37 Note that automated detection from the file-system or search path has
    38 been discontinued.  INCOMPATIBILITY.
    39 
    40 * Name space: former unsynchronized references are now proper
    41 configuration options, with more conventional names:
    42 
    43   long_names   ~> names_long
    44   short_names  ~> names_short
    45   unique_names ~> names_unique
    46 
    47 Minor INCOMPATIBILITY, need to declare options in context like this:
    48 
    49   declare [[names_unique = false]]
    50 
    51 * Literal facts `prop` may contain dummy patterns, e.g. `_ = _`.  Note
    52 that the result needs to be unique, which means fact specifications
    53 may have to be refined after enriching a proof context.
    54 
    55 * Isabelle/Isar reference manual provides more formal references in
    56 syntax diagrams.
    57 
    58 
    59 *** HOL ***
    60 
    61 * Code generation:
    62   - theory Library/Code_Char_ord provides native ordering of characters
    63     in the target language.
    64     
    65 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
    66 
    67 * Finite_Set.thy: locale fun_left_comm uses point-free characterisation;
    68 interpretation proofs may need adjustment.  INCOMPATIBILITY.
    69 
    70 * Nitpick:
    71   - Added "need" and "total_consts" options.
    72   - Reintroduced "show_skolems" option by popular demand.
    73   - Renamed attribute: nitpick_def ~> nitpick_unfold.
    74     INCOMPATIBILITY.
    75 
    76 * Sledgehammer:
    77   - sledgehammer available_provers ~> sledgehammer supported_provers
    78     INCOMPATIBILITY.
    79   - Added support for SNARK and ToFoF-E on SystemOnTPTP and for simply typed
    80     TPTP problems (TFF).
    81   - Added "type_sys", "max_mono_iters", and "max_new_mono_instances" options.
    82 
    83 * "try":
    84   - Added "simp:", "intro:", and "elim:" options.
    85 
    86 * Quickcheck:
    87   - Added "eval" option to evaluate terms for the found counterexample
    88     (currently only supported by the default (exhaustive) tester)
    89   - Added post-processing of terms to obtain readable counterexamples
    90     (currently only supported by the default (exhaustive) tester)
    91 
    92 * Function package: discontinued option "tailrec".
    93 INCOMPATIBILITY. Use partial_function instead.
    94 
    95 * HOL-Probability:
    96   - Caratheodory's extension lemma is now proved for ring_of_sets.
    97   - Infinite products of probability measures are now available.
    98   - Use extended reals instead of positive extended reals.
    99     INCOMPATIBILITY.
   100 
   101 
   102 *** Document preparation ***
   103 
   104 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
   105 isar-ref manual.
   106 
   107 * Localized \isabellestyle switch can be used within blocks or groups
   108 like this:
   109 
   110   \isabellestyle{it}  %preferred default
   111   {\isabellestylett @{text "typewriter stuff"}}
   112 
   113 * New term style "isub" as ad-hoc conversion of variables x1, y23 into
   114 subscripted form x\<^isub>1, y\<^isub>2\<^isub>3.
   115 
   116 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
   117 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
   118 
   119 
   120 *** ML ***
   121 
   122 * Structure Proof_Context follows standard naming scheme.  Old
   123 ProofContext is still available for some time as legacy alias.
   124 
   125 * Structure Timing provides various operations for timing; supersedes
   126 former start_timing/end_timing etc.
   127 
   128 * Path.print is the official way to show file-system paths to users
   129 (including quotes etc.).
   130 
   131 * Inner syntax: identifiers in parse trees of generic categories
   132 "logic", "aprop", "idt" etc. carry position information (disguised as
   133 type constraints).  Occasional INCOMPATIBILITY with non-compliant
   134 translations that choke on unexpected type constraints.  Positions can
   135 be stripped in ML translations via Syntax.strip_positions /
   136 Syntax.strip_positions_ast, or via the syntax constant
   137 "_strip_positions" within parse trees.  As last resort, positions can
   138 be disabled via the configuration option Syntax.positions, which is
   139 called "syntax_positions" in Isar attribute syntax.
   140 
   141 * Discontinued special status of various ML structures that contribute
   142 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
   143 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
   144 refer directly to Ast.Constant, Lexicon.is_identifier,
   145 Syntax_Trans.mk_binder_tr etc.
   146 
   147 * Typed print translation: discontinued show_sorts argument, which is
   148 already available via context of "advanced" translation.
   149 
   150 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
   151 goal states; body tactic needs to address all subgoals uniformly.
   152 
   153 * Slightly more special eq_list/eq_set, with shortcut involving
   154 pointer equality (assumes that eq relation is reflexive).
   155 
   156 * Classical tactics use proper Proof.context instead of historic types
   157 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
   158 operate directly on Proof.context.  Raw type claset retains its use as
   159 snapshot of the classical context, which can be recovered via
   160 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
   161 INCOMPATIBILITY, classical tactics and derived proof methods require
   162 proper Proof.context.
   163 
   164 
   165 
   166 New in Isabelle2011 (January 2011)
   167 ----------------------------------
   168 
   169 *** General ***
   170 
   171 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
   172 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
   173 useful tooltips and hyperlinks produced from its static analysis.  The
   174 bundled component provides an executable Isabelle tool that can be run
   175 like this:
   176 
   177   Isabelle2011/bin/isabelle jedit
   178 
   179 * Significantly improved Isabelle/Isar implementation manual.
   180 
   181 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
   182 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
   183 while the default heap location within that directory lacks that extra
   184 suffix.  This isolates multiple Isabelle installations from each
   185 other, avoiding problems with old settings in new versions.
   186 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
   187 
   188 * Source files are always encoded as UTF-8, instead of old-fashioned
   189 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   190 the following package declarations:
   191 
   192   \usepackage[utf8]{inputenc}
   193   \usepackage{textcomp}
   194 
   195 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   196 a Unicode character is treated as a single symbol, not a sequence of
   197 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   198 contain symbols without further backslash escapes, Unicode can now be
   199 used here as well.  Recall that Symbol.explode in ML provides a
   200 consistent view on symbols, while raw explode (or String.explode)
   201 merely give a byte-oriented representation.
   202 
   203 * Theory loader: source files are primarily located via the master
   204 directory of each theory node (where the .thy file itself resides).
   205 The global load path is still partially available as legacy feature.
   206 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   207 explicit paths, relatively to the theory.
   208 
   209 * Special treatment of ML file names has been discontinued.
   210 Historically, optional extensions .ML or .sml were added on demand --
   211 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   212 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   213 
   214 * Various options that affect pretty printing etc. are now properly
   215 handled within the context via configuration options, instead of
   216 unsynchronized references or print modes.  There are both ML Config.T
   217 entities and Isar declaration attributes to access these.
   218 
   219   ML (Config.T)                 Isar (attribute)
   220 
   221   eta_contract                  eta_contract
   222   show_brackets                 show_brackets
   223   show_sorts                    show_sorts
   224   show_types                    show_types
   225   show_question_marks           show_question_marks
   226   show_consts                   show_consts
   227   show_abbrevs                  show_abbrevs
   228 
   229   Syntax.ast_trace              syntax_ast_trace
   230   Syntax.ast_stat               syntax_ast_stat
   231   Syntax.ambiguity_level        syntax_ambiguity_level
   232 
   233   Goal_Display.goals_limit      goals_limit
   234   Goal_Display.show_main_goal   show_main_goal
   235 
   236   Method.rule_trace             rule_trace
   237 
   238   Thy_Output.display            thy_output_display
   239   Thy_Output.quotes             thy_output_quotes
   240   Thy_Output.indent             thy_output_indent
   241   Thy_Output.source             thy_output_source
   242   Thy_Output.break              thy_output_break
   243 
   244 Note that corresponding "..._default" references in ML may only be
   245 changed globally at the ROOT session setup, but *not* within a theory.
   246 The option "show_abbrevs" supersedes the former print mode
   247 "no_abbrevs" with inverted meaning.
   248 
   249 * More systematic naming of some configuration options.
   250 INCOMPATIBILITY.
   251 
   252   trace_simp  ~>  simp_trace
   253   debug_simp  ~>  simp_debug
   254 
   255 * Support for real valued configuration options, using simplistic
   256 floating-point notation that coincides with the inner syntax for
   257 float_token.
   258 
   259 * Support for real valued preferences (with approximative PGIP type):
   260 front-ends need to accept "pgint" values in float notation.
   261 INCOMPATIBILITY.
   262 
   263 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   264 DejaVu Sans.
   265 
   266 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   267 
   268 
   269 *** Pure ***
   270 
   271 * Command 'type_synonym' (with single argument) replaces somewhat
   272 outdated 'types', which is still available as legacy feature for some
   273 time.
   274 
   275 * Command 'nonterminal' (with 'and' separated list of arguments)
   276 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   277 
   278 * Command 'notepad' replaces former 'example_proof' for
   279 experimentation in Isar without any result.  INCOMPATIBILITY.
   280 
   281 * Locale interpretation commands 'interpret' and 'sublocale' accept
   282 lists of equations to map definitions in a locale to appropriate
   283 entities in the context of the interpretation.  The 'interpretation'
   284 command already provided this functionality.
   285 
   286 * Diagnostic command 'print_dependencies' prints the locale instances
   287 that would be activated if the specified expression was interpreted in
   288 the current context.  Variant "print_dependencies!" assumes a context
   289 without interpretations.
   290 
   291 * Diagnostic command 'print_interps' prints interpretations in proofs
   292 in addition to interpretations in theories.
   293 
   294 * Discontinued obsolete 'global' and 'local' commands to manipulate
   295 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   296 Sign.root_path and Sign.local_path may be applied directly where this
   297 feature is still required for historical reasons.
   298 
   299 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   300 'definition' instead.
   301 
   302 * The "prems" fact, which refers to the accidental collection of
   303 foundational premises in the context, is now explicitly marked as
   304 legacy feature and will be discontinued soon.  Consider using "assms"
   305 of the head statement or reference facts by explicit names.
   306 
   307 * Document antiquotations @{class} and @{type} print classes and type
   308 constructors.
   309 
   310 * Document antiquotation @{file} checks file/directory entries within
   311 the local file system.
   312 
   313 
   314 *** HOL ***
   315 
   316 * Coercive subtyping: functions can be declared as coercions and type
   317 inference will add them as necessary upon input of a term.  Theory
   318 Complex_Main declares real :: nat => real and real :: int => real as
   319 coercions. A coercion function f is declared like this:
   320 
   321   declare [[coercion f]]
   322 
   323 To lift coercions through type constructors (e.g. from nat => real to
   324 nat list => real list), map functions can be declared, e.g.
   325 
   326   declare [[coercion_map map]]
   327 
   328 Currently coercion inference is activated only in theories including
   329 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   330 the configuration option "coercion_enabled", e.g. it can be enabled in
   331 other theories like this:
   332 
   333   declare [[coercion_enabled]]
   334 
   335 * Command 'partial_function' provides basic support for recursive
   336 function definitions over complete partial orders.  Concrete instances
   337 are provided for i) the option type, ii) tail recursion on arbitrary
   338 types, and iii) the heap monad of Imperative_HOL.  See
   339 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   340 for examples.
   341 
   342 * Function package: f.psimps rules are no longer implicitly declared
   343 as [simp].  INCOMPATIBILITY.
   344 
   345 * Datatype package: theorems generated for executable equality (class
   346 "eq") carry proper names and are treated as default code equations.
   347 
   348 * Inductive package: now offers command 'inductive_simps' to
   349 automatically derive instantiated and simplified equations for
   350 inductive predicates, similar to 'inductive_cases'.
   351 
   352 * Command 'enriched_type' allows to register properties of the
   353 functorial structure of types.
   354 
   355 * Improved infrastructure for term evaluation using code generator
   356 techniques, in particular static evaluation conversions.
   357 
   358 * Code generator: Scala (2.8 or higher) has been added to the target
   359 languages.
   360 
   361 * Code generator: globbing constant expressions "*" and "Theory.*"
   362 have been replaced by the more idiomatic "_" and "Theory._".
   363 INCOMPATIBILITY.
   364 
   365 * Code generator: export_code without explicit file declaration prints
   366 to standard output.  INCOMPATIBILITY.
   367 
   368 * Code generator: do not print function definitions for case
   369 combinators any longer.
   370 
   371 * Code generator: simplification with rules determined with
   372 src/Tools/Code/code_simp.ML and method "code_simp".
   373 
   374 * Code generator for records: more idiomatic representation of record
   375 types.  Warning: records are not covered by ancient SML code
   376 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   377 rep_datatype declaration helps to succeed then:
   378 
   379   record 'a foo = ...
   380   ...
   381   rep_datatype foo_ext ...
   382 
   383 * Records: logical foundation type for records does not carry a
   384 '_type' suffix any longer (obsolete due to authentic syntax).
   385 INCOMPATIBILITY.
   386 
   387 * Quickcheck now by default uses exhaustive testing instead of random
   388 testing.  Random testing can be invoked by "quickcheck [random]",
   389 exhaustive testing by "quickcheck [exhaustive]".
   390 
   391 * Quickcheck instantiates polymorphic types with small finite
   392 datatypes by default. This enables a simple execution mechanism to
   393 handle quantifiers and function equality over the finite datatypes.
   394 
   395 * Quickcheck random generator has been renamed from "code" to
   396 "random".  INCOMPATIBILITY.
   397 
   398 * Quickcheck now has a configurable time limit which is set to 30
   399 seconds by default. This can be changed by adding [timeout = n] to the
   400 quickcheck command. The time limit for Auto Quickcheck is still set
   401 independently.
   402 
   403 * Quickcheck in locales considers interpretations of that locale for
   404 counter example search.
   405 
   406 * Sledgehammer:
   407   - Added "smt" and "remote_smt" provers based on the "smt" proof
   408     method. See the Sledgehammer manual for details ("isabelle doc
   409     sledgehammer").
   410   - Renamed commands:
   411     sledgehammer atp_info ~> sledgehammer running_provers
   412     sledgehammer atp_kill ~> sledgehammer kill_provers
   413     sledgehammer available_atps ~> sledgehammer available_provers
   414     INCOMPATIBILITY.
   415   - Renamed options:
   416     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   417     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   418     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   419     (and "ms" and "min" are no longer supported)
   420     INCOMPATIBILITY.
   421 
   422 * Nitpick:
   423   - Renamed options:
   424     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   425     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   426     INCOMPATIBILITY.
   427   - Added support for partial quotient types.
   428   - Added local versions of the "Nitpick.register_xxx" functions.
   429   - Added "whack" option.
   430   - Allow registration of quotient types as codatatypes.
   431   - Improved "merge_type_vars" option to merge more types.
   432   - Removed unsound "fast_descrs" option.
   433   - Added custom symmetry breaking for datatypes, making it possible to reach
   434     higher cardinalities.
   435   - Prevent the expansion of too large definitions.
   436 
   437 * Proof methods "metis" and "meson" now have configuration options
   438 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   439 to diagnose these tools. E.g.
   440 
   441     using [[metis_trace = true]]
   442 
   443 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   444 manually as command 'solve_direct'.
   445 
   446 * The default SMT solver Z3 must be enabled explicitly (due to
   447 licensing issues) by setting the environment variable
   448 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   449 commercial applications, the SMT solver CVC3 is provided as fall-back;
   450 changing the SMT solver is done via the configuration option
   451 "smt_solver".
   452 
   453 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   454 i.e. "remote_cvc3" and "remote_z3".
   455 
   456 * Added basic SMT support for datatypes, records, and typedefs using
   457 the oracle mode (no proofs).  Direct support of pairs has been dropped
   458 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   459 support for a similar behavior).  Minor INCOMPATIBILITY.
   460 
   461 * Changed SMT configuration options:
   462   - Renamed:
   463     z3_proofs ~> smt_oracle (with inverted meaning)
   464     z3_trace_assms ~> smt_trace_used_facts
   465     INCOMPATIBILITY.
   466   - Added:
   467     smt_verbose
   468     smt_random_seed
   469     smt_datatypes
   470     smt_infer_triggers
   471     smt_monomorph_limit
   472     cvc3_options
   473     remote_cvc3_options
   474     remote_z3_options
   475     yices_options
   476 
   477 * Boogie output files (.b2i files) need to be declared in the theory
   478 header.
   479 
   480 * Simplification procedure "list_to_set_comprehension" rewrites list
   481 comprehensions applied to List.set to set comprehensions.  Occasional
   482 INCOMPATIBILITY, may be deactivated like this:
   483 
   484   declare [[simproc del: list_to_set_comprehension]]
   485 
   486 * Removed old version of primrec package.  INCOMPATIBILITY.
   487 
   488 * Removed simplifier congruence rule of "prod_case", as has for long
   489 been the case with "split".  INCOMPATIBILITY.
   490 
   491 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   492 
   493 * Removed [split_format ... and ... and ...] version of
   494 [split_format].  Potential INCOMPATIBILITY.
   495 
   496 * Predicate "sorted" now defined inductively, with nice induction
   497 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   498 
   499 * Constant "contents" renamed to "the_elem", to free the generic name
   500 contents for other uses.  INCOMPATIBILITY.
   501 
   502 * Renamed class eq and constant eq (for code generation) to class
   503 equal and constant equal, plus renaming of related facts and various
   504 tuning.  INCOMPATIBILITY.
   505 
   506 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   507 
   508 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   509 INCOMPATIBILITY.
   510 
   511 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   512 avoid confusion with finite sets.  INCOMPATIBILITY.
   513 
   514 * Abandoned locales equiv, congruent and congruent2 for equivalence
   515 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   516 for congruent(2)).
   517 
   518 * Some previously unqualified names have been qualified:
   519 
   520   types
   521     bool ~> HOL.bool
   522     nat ~> Nat.nat
   523 
   524   constants
   525     Trueprop ~> HOL.Trueprop
   526     True ~> HOL.True
   527     False ~> HOL.False
   528     op & ~> HOL.conj
   529     op | ~> HOL.disj
   530     op --> ~> HOL.implies
   531     op = ~> HOL.eq
   532     Not ~> HOL.Not
   533     The ~> HOL.The
   534     All ~> HOL.All
   535     Ex ~> HOL.Ex
   536     Ex1 ~> HOL.Ex1
   537     Let ~> HOL.Let
   538     If ~> HOL.If
   539     Ball ~> Set.Ball
   540     Bex ~> Set.Bex
   541     Suc ~> Nat.Suc
   542     Pair ~> Product_Type.Pair
   543     fst ~> Product_Type.fst
   544     snd ~> Product_Type.snd
   545     curry ~> Product_Type.curry
   546     op : ~> Set.member
   547     Collect ~> Set.Collect
   548 
   549 INCOMPATIBILITY.
   550 
   551 * More canonical naming convention for some fundamental definitions:
   552 
   553     bot_bool_eq ~> bot_bool_def
   554     top_bool_eq ~> top_bool_def
   555     inf_bool_eq ~> inf_bool_def
   556     sup_bool_eq ~> sup_bool_def
   557     bot_fun_eq  ~> bot_fun_def
   558     top_fun_eq  ~> top_fun_def
   559     inf_fun_eq  ~> inf_fun_def
   560     sup_fun_eq  ~> sup_fun_def
   561 
   562 INCOMPATIBILITY.
   563 
   564 * More stylized fact names:
   565 
   566   expand_fun_eq ~> fun_eq_iff
   567   expand_set_eq ~> set_eq_iff
   568   set_ext       ~> set_eqI
   569   nat_number    ~> eval_nat_numeral
   570 
   571 INCOMPATIBILITY.
   572 
   573 * Refactoring of code-generation specific operations in theory List:
   574 
   575   constants
   576     null ~> List.null
   577 
   578   facts
   579     mem_iff ~> member_def
   580     null_empty ~> null_def
   581 
   582 INCOMPATIBILITY.  Note that these were not supposed to be used
   583 regularly unless for striking reasons; their main purpose was code
   584 generation.
   585 
   586 Various operations from the Haskell prelude are used for generating
   587 Haskell code.
   588 
   589 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   590 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   591 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   592 
   593 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   594 "*" and "+" respectively.  INCOMPATIBILITY.
   595 
   596 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   597 "Sum_Type.Plus" instead.
   598 
   599 * Constant "split" has been merged with constant "prod_case"; names of
   600 ML functions, facts etc. involving split have been retained so far,
   601 though.  INCOMPATIBILITY.
   602 
   603 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   604 instead.  INCOMPATIBILITY.
   605 
   606 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   607 INCOMPATIBILITY.
   608 
   609 * Former theory Library/Enum is now part of the HOL-Main image.
   610 INCOMPATIBILITY: all constants of the Enum theory now have to be
   611 referred to by its qualified name.
   612 
   613   enum    ~>  Enum.enum
   614   nlists  ~>  Enum.nlists
   615   product ~>  Enum.product
   616 
   617 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   618 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   619 INCOMPATIBILITY.
   620 
   621 * Theory Library/SetsAndFunctions has been split into
   622 Library/Function_Algebras and Library/Set_Algebras; canonical names
   623 for instance definitions for functions; various improvements.
   624 INCOMPATIBILITY.
   625 
   626 * Theory Library/Multiset provides stable quicksort implementation of
   627 sort_key.
   628 
   629 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   630 INCOMPATIBILITY.
   631 
   632 * Session Multivariate_Analysis: introduced a type class for euclidean
   633 space.  Most theorems are now stated in terms of euclidean spaces
   634 instead of finite cartesian products.
   635 
   636   types
   637     real ^ 'n ~>  'a::real_vector
   638               ~>  'a::euclidean_space
   639               ~>  'a::ordered_euclidean_space
   640         (depends on your needs)
   641 
   642   constants
   643      _ $ _        ~> _ $$ _
   644      \<chi> x. _  ~> \<chi>\<chi> x. _
   645      CARD('n)     ~> DIM('a)
   646 
   647 Also note that the indices are now natural numbers and not from some
   648 finite type. Finite cartesian products of euclidean spaces, products
   649 of euclidean spaces the real and complex numbers are instantiated to
   650 be euclidean_spaces.  INCOMPATIBILITY.
   651 
   652 * Session Probability: introduced pextreal as positive extended real
   653 numbers.  Use pextreal as value for measures.  Introduce the
   654 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   655 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   656 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   657 
   658 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   659 INCOMPATIBILITY.
   660 
   661 * Session SPARK (with image HOL-SPARK) provides commands to load and
   662 prove verification conditions generated by the SPARK Ada program
   663 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   664 
   665 
   666 *** HOL-Algebra ***
   667 
   668 * Theorems for additive ring operations (locale abelian_monoid and
   669 descendants) are generated by interpretation from their multiplicative
   670 counterparts.  Names (in particular theorem names) have the mandatory
   671 qualifier 'add'.  Previous theorem names are redeclared for
   672 compatibility.
   673 
   674 * Structure "int_ring" is now an abbreviation (previously a
   675 definition).  This fits more natural with advanced interpretations.
   676 
   677 
   678 *** HOLCF ***
   679 
   680 * The domain package now runs in definitional mode by default: The
   681 former command 'new_domain' is now called 'domain'.  To use the domain
   682 package in its original axiomatic mode, use 'domain (unsafe)'.
   683 INCOMPATIBILITY.
   684 
   685 * The new class "domain" is now the default sort.  Class "predomain"
   686 is an unpointed version of "domain". Theories can be updated by
   687 replacing sort annotations as shown below.  INCOMPATIBILITY.
   688 
   689   'a::type ~> 'a::countable
   690   'a::cpo  ~> 'a::predomain
   691   'a::pcpo ~> 'a::domain
   692 
   693 * The old type class "rep" has been superseded by class "domain".
   694 Accordingly, users of the definitional package must remove any
   695 "default_sort rep" declarations.  INCOMPATIBILITY.
   696 
   697 * The domain package (definitional mode) now supports unpointed
   698 predomain argument types, as long as they are marked 'lazy'. (Strict
   699 arguments must be in class "domain".) For example, the following
   700 domain definition now works:
   701 
   702   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   703 
   704 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   705 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   706 'a option, and 'a list.  Additionally, it configures fixrec and the
   707 domain package to work with these types.  For example:
   708 
   709   fixrec isInl :: "('a + 'b) u -> tr"
   710     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   711 
   712   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   713 
   714 * The "(permissive)" option of fixrec has been replaced with a
   715 per-equation "(unchecked)" option. See
   716 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
   717 
   718 * The "bifinite" class no longer fixes a constant "approx"; the class
   719 now just asserts that such a function exists.  INCOMPATIBILITY.
   720 
   721 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
   722 defines an embedding of type 'a defl into udom by default; instances
   723 of "bifinite" and "domain" classes are available in
   724 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
   725 
   726 * The syntax "REP('a)" has been replaced with "DEFL('a)".
   727 
   728 * The predicate "directed" has been removed.  INCOMPATIBILITY.
   729 
   730 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
   731 
   732 * The function "cprod_map" has been renamed to "prod_map".
   733 INCOMPATIBILITY.
   734 
   735 * The monadic bind operator on each powerdomain has new binder syntax
   736 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
   737 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
   738 
   739 * The infix syntax for binary union on each powerdomain has changed
   740 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
   741 syntax.  INCOMPATIBILITY.
   742 
   743 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
   744 still supported as an input translation.
   745 
   746 * Renamed some theorems (the original names are also still available).
   747 
   748   expand_fun_below   ~> fun_below_iff
   749   below_fun_ext      ~> fun_belowI
   750   expand_cfun_eq     ~> cfun_eq_iff
   751   ext_cfun           ~> cfun_eqI
   752   expand_cfun_below  ~> cfun_below_iff
   753   below_cfun_ext     ~> cfun_belowI
   754   cont2cont_Rep_CFun ~> cont2cont_APP
   755 
   756 * The Abs and Rep functions for various types have changed names.
   757 Related theorem names have also changed to match. INCOMPATIBILITY.
   758 
   759   Rep_CFun  ~> Rep_cfun
   760   Abs_CFun  ~> Abs_cfun
   761   Rep_Sprod ~> Rep_sprod
   762   Abs_Sprod ~> Abs_sprod
   763   Rep_Ssum  ~> Rep_ssum
   764   Abs_Ssum  ~> Abs_ssum
   765 
   766 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   767 been renamed to *_bottom_iff.  INCOMPATIBILITY.
   768 
   769 * Various changes to bisimulation/coinduction with domain package:
   770 
   771   - Definitions of "bisim" constants no longer mention definedness.
   772   - With mutual recursion, "bisim" predicate is now curried.
   773   - With mutual recursion, each type gets a separate coind theorem.
   774   - Variable names in bisim_def and coinduct rules have changed.
   775 
   776 INCOMPATIBILITY.
   777 
   778 * Case combinators generated by the domain package for type "foo" are
   779 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
   780 
   781 * Several theorems have been renamed to more accurately reflect the
   782 names of constants and types involved.  INCOMPATIBILITY.
   783 
   784   thelub_const    ~> lub_const
   785   lub_const       ~> is_lub_const
   786   thelubI         ~> lub_eqI
   787   is_lub_lub      ~> is_lubD2
   788   lubI            ~> is_lub_lub
   789   unique_lub      ~> is_lub_unique
   790   is_ub_lub       ~> is_lub_rangeD1
   791   lub_bin_chain   ~> is_lub_bin_chain
   792   lub_fun         ~> is_lub_fun
   793   thelub_fun      ~> lub_fun
   794   thelub_cfun     ~> lub_cfun
   795   thelub_Pair     ~> lub_Pair
   796   lub_cprod       ~> is_lub_prod
   797   thelub_cprod    ~> lub_prod
   798   minimal_cprod   ~> minimal_prod
   799   inst_cprod_pcpo ~> inst_prod_pcpo
   800   UU_I            ~> bottomI
   801   compact_UU      ~> compact_bottom
   802   deflation_UU    ~> deflation_bottom
   803   finite_deflation_UU ~> finite_deflation_bottom
   804 
   805 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
   806 
   807   sq_ord_less_eq_trans ~> below_eq_trans
   808   sq_ord_eq_less_trans ~> eq_below_trans
   809   refl_less            ~> below_refl
   810   trans_less           ~> below_trans
   811   antisym_less         ~> below_antisym
   812   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
   813   box_less             ~> box_below
   814   rev_trans_less       ~> rev_below_trans
   815   not_less2not_eq      ~> not_below2not_eq
   816   less_UU_iff          ~> below_UU_iff
   817   flat_less_iff        ~> flat_below_iff
   818   adm_less             ~> adm_below
   819   adm_not_less         ~> adm_not_below
   820   adm_compact_not_less ~> adm_compact_not_below
   821   less_fun_def         ~> below_fun_def
   822   expand_fun_less      ~> fun_below_iff
   823   less_fun_ext         ~> fun_belowI
   824   less_discr_def       ~> below_discr_def
   825   discr_less_eq        ~> discr_below_eq
   826   less_unit_def        ~> below_unit_def
   827   less_cprod_def       ~> below_prod_def
   828   prod_lessI           ~> prod_belowI
   829   Pair_less_iff        ~> Pair_below_iff
   830   fst_less_iff         ~> fst_below_iff
   831   snd_less_iff         ~> snd_below_iff
   832   expand_cfun_less     ~> cfun_below_iff
   833   less_cfun_ext        ~> cfun_belowI
   834   injection_less       ~> injection_below
   835   less_up_def          ~> below_up_def
   836   not_Iup_less         ~> not_Iup_below
   837   Iup_less             ~> Iup_below
   838   up_less              ~> up_below
   839   Def_inject_less_eq   ~> Def_below_Def
   840   Def_less_is_eq       ~> Def_below_iff
   841   spair_less_iff       ~> spair_below_iff
   842   less_sprod           ~> below_sprod
   843   spair_less           ~> spair_below
   844   sfst_less_iff        ~> sfst_below_iff
   845   ssnd_less_iff        ~> ssnd_below_iff
   846   fix_least_less       ~> fix_least_below
   847   dist_less_one        ~> dist_below_one
   848   less_ONE             ~> below_ONE
   849   ONE_less_iff         ~> ONE_below_iff
   850   less_sinlD           ~> below_sinlD
   851   less_sinrD           ~> below_sinrD
   852 
   853 
   854 *** FOL and ZF ***
   855 
   856 * All constant names are now qualified internally and use proper
   857 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
   858 
   859 
   860 *** ML ***
   861 
   862 * Antiquotation @{assert} inlines a function bool -> unit that raises
   863 Fail if the argument is false.  Due to inlining the source position of
   864 failed assertions is included in the error output.
   865 
   866 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
   867 text is in practice always evaluated with a stable theory checkpoint.
   868 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
   869 
   870 * Antiquotation @{theory A} refers to theory A from the ancestry of
   871 the current context, not any accidental theory loader state as before.
   872 Potential INCOMPATIBILITY, subtle change in semantics.
   873 
   874 * Syntax.pretty_priority (default 0) configures the required priority
   875 of pretty-printed output and thus affects insertion of parentheses.
   876 
   877 * Syntax.default_root (default "any") configures the inner syntax
   878 category (nonterminal symbol) for parsing of terms.
   879 
   880 * Former exception Library.UnequalLengths now coincides with
   881 ListPair.UnequalLengths.
   882 
   883 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
   884 main functionality is provided by structure Simplifier.
   885 
   886 * Renamed raw "explode" function to "raw_explode" to emphasize its
   887 meaning.  Note that internally to Isabelle, Symbol.explode is used in
   888 almost all situations.
   889 
   890 * Discontinued obsolete function sys_error and exception SYS_ERROR.
   891 See implementation manual for further details on exceptions in
   892 Isabelle/ML.
   893 
   894 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   895 meaning.
   896 
   897 * Renamed structure PureThy to Pure_Thy and moved most of its
   898 operations to structure Global_Theory, to emphasize that this is
   899 rarely-used global-only stuff.
   900 
   901 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
   902 instead (or tracing for high-volume output).
   903 
   904 * Configuration option show_question_marks only affects regular pretty
   905 printing of types and terms, not raw Term.string_of_vname.
   906 
   907 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
   908 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
   909 @{thms} for most purposes.
   910 
   911 * ML structure Unsynchronized is never opened, not even in Isar
   912 interaction mode as before.  Old Unsynchronized.set etc. have been
   913 discontinued -- use plain := instead.  This should be *rare* anyway,
   914 since modern tools always work via official context data, notably
   915 configuration options.
   916 
   917 * Parallel and asynchronous execution requires special care concerning
   918 interrupts.  Structure Exn provides some convenience functions that
   919 avoid working directly with raw Interrupt.  User code must not absorb
   920 interrupts -- intermediate handling (for cleanup etc.) needs to be
   921 followed by re-raising of the original exception.  Another common
   922 source of mistakes are "handle _" patterns, which make the meaning of
   923 the program subject to physical effects of the environment.
   924 
   925 
   926 
   927 New in Isabelle2009-2 (June 2010)
   928 ---------------------------------
   929 
   930 *** General ***
   931 
   932 * Authentic syntax for *all* logical entities (type classes, type
   933 constructors, term constants): provides simple and robust
   934 correspondence between formal entities and concrete syntax.  Within
   935 the parse tree / AST representations, "constants" are decorated by
   936 their category (class, type, const) and spelled out explicitly with
   937 their full internal name.
   938 
   939 Substantial INCOMPATIBILITY concerning low-level syntax declarations
   940 and translations (translation rules and translation functions in ML).
   941 Some hints on upgrading:
   942 
   943   - Many existing uses of 'syntax' and 'translations' can be replaced
   944     by more modern 'type_notation', 'notation' and 'abbreviation',
   945     which are independent of this issue.
   946 
   947   - 'translations' require markup within the AST; the term syntax
   948     provides the following special forms:
   949 
   950       CONST c   -- produces syntax version of constant c from context
   951       XCONST c  -- literally c, checked as constant from context
   952       c         -- literally c, if declared by 'syntax'
   953 
   954     Plain identifiers are treated as AST variables -- occasionally the
   955     system indicates accidental variables via the error "rhs contains
   956     extra variables".
   957 
   958     Type classes and type constructors are marked according to their
   959     concrete syntax.  Some old translations rules need to be written
   960     for the "type" category, using type constructor application
   961     instead of pseudo-term application of the default category
   962     "logic".
   963 
   964   - 'parse_translation' etc. in ML may use the following
   965     antiquotations:
   966 
   967       @{class_syntax c}   -- type class c within parse tree / AST
   968       @{term_syntax c}    -- type constructor c within parse tree / AST
   969       @{const_syntax c}   -- ML version of "CONST c" above
   970       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
   971 
   972   - Literal types within 'typed_print_translations', i.e. those *not*
   973     represented as pseudo-terms are represented verbatim.  Use @{class
   974     c} or @{type_name c} here instead of the above syntax
   975     antiquotations.
   976 
   977 Note that old non-authentic syntax was based on unqualified base
   978 names, so all of the above "constant" names would coincide.  Recall
   979 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
   980 diagnose syntax problems.
   981 
   982 * Type constructors admit general mixfix syntax, not just infix.
   983 
   984 * Concrete syntax may be attached to local entities without a proof
   985 body, too.  This works via regular mixfix annotations for 'fix',
   986 'def', 'obtain' etc. or via the explicit 'write' command, which is
   987 similar to the 'notation' command in theory specifications.
   988 
   989 * Discontinued unnamed infix syntax (legacy feature for many years) --
   990 need to specify constant name and syntax separately.  Internal ML
   991 datatype constructors have been renamed from InfixName to Infix etc.
   992 Minor INCOMPATIBILITY.
   993 
   994 * Schematic theorem statements need to be explicitly markup as such,
   995 via commands 'schematic_lemma', 'schematic_theorem',
   996 'schematic_corollary'.  Thus the relevance of the proof is made
   997 syntactically clear, which impacts performance in a parallel or
   998 asynchronous interactive environment.  Minor INCOMPATIBILITY.
   999 
  1000 * Use of cumulative prems via "!" in some proof methods has been
  1001 discontinued (old legacy feature).
  1002 
  1003 * References 'trace_simp' and 'debug_simp' have been replaced by
  1004 configuration options stored in the context. Enabling tracing (the
  1005 case of debugging is similar) in proofs works via
  1006 
  1007   using [[trace_simp = true]]
  1008 
  1009 Tracing is then active for all invocations of the simplifier in
  1010 subsequent goal refinement steps. Tracing may also still be enabled or
  1011 disabled via the ProofGeneral settings menu.
  1012 
  1013 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  1014 'hide_fact' replace the former 'hide' KIND command.  Minor
  1015 INCOMPATIBILITY.
  1016 
  1017 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  1018 more efficient than combinations with -q1 or -q2.
  1019 
  1020 
  1021 *** Pure ***
  1022 
  1023 * Proofterms record type-class reasoning explicitly, using the
  1024 "unconstrain" operation internally.  This eliminates all sort
  1025 constraints from a theorem and proof, introducing explicit
  1026 OFCLASS-premises.  On the proof term level, this operation is
  1027 automatically applied at theorem boundaries, such that closed proofs
  1028 are always free of sort constraints.  INCOMPATIBILITY for tools that
  1029 inspect proof terms.
  1030 
  1031 * Local theory specifications may depend on extra type variables that
  1032 are not present in the result type -- arguments TYPE('a) :: 'a itself
  1033 are added internally.  For example:
  1034 
  1035   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  1036 
  1037 * Predicates of locales introduced by classes carry a mandatory
  1038 "class" prefix.  INCOMPATIBILITY.
  1039 
  1040 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  1041 
  1042 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  1043 'class' instead.
  1044 
  1045 * Command 'code_reflect' allows to incorporate generated ML code into
  1046 runtime environment; replaces immature code_datatype antiquotation.
  1047 INCOMPATIBILITY.
  1048 
  1049 * Code generator: simple concept for abstract datatypes obeying
  1050 invariants.
  1051 
  1052 * Code generator: details of internal data cache have no impact on the
  1053 user space functionality any longer.
  1054 
  1055 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1056 subgoals.  This is more appropriate for interpretations with 'where'.
  1057 INCOMPATIBILITY.
  1058 
  1059 * Command 'example_proof' opens an empty proof body.  This allows to
  1060 experiment with Isar, without producing any persistent result.
  1061 
  1062 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1063 within a local theory context, with explicit checking of the
  1064 constructors involved (in contrast to the raw 'syntax' versions).
  1065 
  1066 * Commands 'types' and 'typedecl' now work within a local theory
  1067 context -- without introducing dependencies on parameters or
  1068 assumptions, which is not possible in Isabelle/Pure.
  1069 
  1070 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1071 within a local theory context.  Minor INCOMPATIBILITY.
  1072 
  1073 
  1074 *** HOL ***
  1075 
  1076 * Command 'typedef' now works within a local theory context -- without
  1077 introducing dependencies on parameters or assumptions, which is not
  1078 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1079 contain multiple interpretations of local typedefs (with different
  1080 non-emptiness proofs), even in a global theory context.
  1081 
  1082 * New package for quotient types.  Commands 'quotient_type' and
  1083 'quotient_definition' may be used for defining types and constants by
  1084 quotient constructions.  An example is the type of integers created by
  1085 quotienting pairs of natural numbers:
  1086 
  1087   fun
  1088     intrel :: "(nat * nat) => (nat * nat) => bool"
  1089   where
  1090     "intrel (x, y) (u, v) = (x + v = u + y)"
  1091 
  1092   quotient_type int = "nat * nat" / intrel
  1093     by (auto simp add: equivp_def expand_fun_eq)
  1094 
  1095   quotient_definition
  1096     "0::int" is "(0::nat, 0::nat)"
  1097 
  1098 The method "lifting" can be used to lift of theorems from the
  1099 underlying "raw" type to the quotient type.  The example
  1100 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1101 construction and provides a reasoning infrastructure for finite sets.
  1102 
  1103 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1104 clash with new theory Quotient in Main HOL.
  1105 
  1106 * Moved the SMT binding into the main HOL session, eliminating
  1107 separate HOL-SMT session.
  1108 
  1109 * List membership infix mem operation is only an input abbreviation.
  1110 INCOMPATIBILITY.
  1111 
  1112 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1113 for future developements; former Library/Word.thy is still present in
  1114 the AFP entry RSAPPS.
  1115 
  1116 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1117 longer shadowed.  INCOMPATIBILITY.
  1118 
  1119 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1120 INCOMPATIBILITY.
  1121 
  1122 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1123 INCOMPATIBILITY.
  1124 
  1125 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1126 instead.  INCOMPATIBILITY.
  1127 
  1128 * Dropped several real-specific versions of lemmas about floor and
  1129 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1130 instead.  INCOMPATIBILITY.
  1131 
  1132   floor_number_of_eq         ~> floor_number_of
  1133   le_floor_eq_number_of      ~> number_of_le_floor
  1134   le_floor_eq_zero           ~> zero_le_floor
  1135   le_floor_eq_one            ~> one_le_floor
  1136   floor_less_eq_number_of    ~> floor_less_number_of
  1137   floor_less_eq_zero         ~> floor_less_zero
  1138   floor_less_eq_one          ~> floor_less_one
  1139   less_floor_eq_number_of    ~> number_of_less_floor
  1140   less_floor_eq_zero         ~> zero_less_floor
  1141   less_floor_eq_one          ~> one_less_floor
  1142   floor_le_eq_number_of      ~> floor_le_number_of
  1143   floor_le_eq_zero           ~> floor_le_zero
  1144   floor_le_eq_one            ~> floor_le_one
  1145   floor_subtract_number_of   ~> floor_diff_number_of
  1146   floor_subtract_one         ~> floor_diff_one
  1147   ceiling_number_of_eq       ~> ceiling_number_of
  1148   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1149   ceiling_le_zero_eq         ~> ceiling_le_zero
  1150   ceiling_le_eq_one          ~> ceiling_le_one
  1151   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1152   less_ceiling_eq_zero       ~> zero_less_ceiling
  1153   less_ceiling_eq_one        ~> one_less_ceiling
  1154   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1155   ceiling_less_eq_zero       ~> ceiling_less_zero
  1156   ceiling_less_eq_one        ~> ceiling_less_one
  1157   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1158   le_ceiling_eq_zero         ~> zero_le_ceiling
  1159   le_ceiling_eq_one          ~> one_le_ceiling
  1160   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1161   ceiling_subtract_one       ~> ceiling_diff_one
  1162 
  1163 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1164 application of the various fold combinators on finite sets.
  1165 
  1166 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1167 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1168 implementation.  INCOMPATIBILTY.
  1169 
  1170 * Theory Library/Coinductive_List has been removed -- superseded by
  1171 AFP/thys/Coinductive.
  1172 
  1173 * Theory PReal, including the type "preal" and related operations, has
  1174 been removed.  INCOMPATIBILITY.
  1175 
  1176 * Real: new development using Cauchy Sequences.
  1177 
  1178 * Split off theory "Big_Operators" containing setsum, setprod,
  1179 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1180 
  1181 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1182 "Int" etc.  INCOMPATIBILITY.
  1183 
  1184 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1185 
  1186 * New set of rules "ac_simps" provides combined assoc / commute
  1187 rewrites for all interpretations of the appropriate generic locales.
  1188 
  1189 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1190 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1191 appropriate and more consistent names suitable for name prefixes
  1192 within the HOL theories.  INCOMPATIBILITY.
  1193 
  1194 * Some generic constants have been put to appropriate theories:
  1195   - less_eq, less: Orderings
  1196   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1197   - inverse, divide: Rings
  1198 INCOMPATIBILITY.
  1199 
  1200 * More consistent naming of type classes involving orderings (and
  1201 lattices):
  1202 
  1203     lower_semilattice                   ~> semilattice_inf
  1204     upper_semilattice                   ~> semilattice_sup
  1205 
  1206     dense_linear_order                  ~> dense_linorder
  1207 
  1208     pordered_ab_group_add               ~> ordered_ab_group_add
  1209     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1210     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1211     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1212     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1213     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1214     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1215     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1216     pordered_comm_ring                  ~> ordered_comm_ring
  1217     pordered_comm_semiring              ~> ordered_comm_semiring
  1218     pordered_ring                       ~> ordered_ring
  1219     pordered_ring_abs                   ~> ordered_ring_abs
  1220     pordered_semiring                   ~> ordered_semiring
  1221 
  1222     ordered_ab_group_add                ~> linordered_ab_group_add
  1223     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1224     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1225     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1226     ordered_field                       ~> linordered_field
  1227     ordered_field_no_lb                 ~> linordered_field_no_lb
  1228     ordered_field_no_ub                 ~> linordered_field_no_ub
  1229     ordered_field_dense_linear_order    ~> dense_linordered_field
  1230     ordered_idom                        ~> linordered_idom
  1231     ordered_ring                        ~> linordered_ring
  1232     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1233     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1234     ordered_ring_strict                 ~> linordered_ring_strict
  1235     ordered_semidom                     ~> linordered_semidom
  1236     ordered_semiring                    ~> linordered_semiring
  1237     ordered_semiring_1                  ~> linordered_semiring_1
  1238     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1239     ordered_semiring_strict             ~> linordered_semiring_strict
  1240 
  1241   The following slightly odd type classes have been moved to a
  1242   separate theory Library/Lattice_Algebras:
  1243 
  1244     lordered_ab_group_add               ~> lattice_ab_group_add
  1245     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1246     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1247     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1248     lordered_ring                       ~> lattice_ring
  1249 
  1250 INCOMPATIBILITY.
  1251 
  1252 * Refined field classes:
  1253   - classes division_ring_inverse_zero, field_inverse_zero,
  1254     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1255     subsumes former division_by_zero class;
  1256   - numerous lemmas have been ported from field to division_ring.
  1257 INCOMPATIBILITY.
  1258 
  1259 * Refined algebra theorem collections:
  1260   - dropped theorem group group_simps, use algebra_simps instead;
  1261   - dropped theorem group ring_simps, use field_simps instead;
  1262   - proper theorem collection field_simps subsumes former theorem
  1263     groups field_eq_simps and field_simps;
  1264   - dropped lemma eq_minus_self_iff which is a duplicate for
  1265     equal_neg_zero.
  1266 INCOMPATIBILITY.
  1267 
  1268 * Theory Finite_Set and List: some lemmas have been generalized from
  1269 sets to lattices:
  1270 
  1271   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1272   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1273   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1274   union_Union_fold_union        ~> sup_Sup_fold_sup
  1275   Inter_fold_inter              ~> Inf_fold_inf
  1276   Union_fold_union              ~> Sup_fold_sup
  1277   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1278   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1279   INTER_fold_inter              ~> INFI_fold_inf
  1280   UNION_fold_union              ~> SUPR_fold_sup
  1281 
  1282 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1283 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1284 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1285 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1286 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1287 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1288 
  1289 * Reorganized theory Multiset: swapped notation of pointwise and
  1290 multiset order:
  1291 
  1292   - pointwise ordering is instance of class order with standard syntax
  1293     <= and <;
  1294   - multiset ordering has syntax <=# and <#; partial order properties
  1295     are provided by means of interpretation with prefix
  1296     multiset_order;
  1297   - less duplication, less historical organization of sections,
  1298     conversion from associations lists to multisets, rudimentary code
  1299     generation;
  1300   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1301     if needed.
  1302 
  1303 Renamed:
  1304 
  1305   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1306   multi_count_ext  ~>  multiset_ext
  1307   diff_union_inverse2  ~>  diff_union_cancelR
  1308 
  1309 INCOMPATIBILITY.
  1310 
  1311 * Theory Permutation: replaced local "remove" by List.remove1.
  1312 
  1313 * Code generation: ML and OCaml code is decorated with signatures.
  1314 
  1315 * Theory List: added transpose.
  1316 
  1317 * Library/Nat_Bijection.thy is a collection of bijective functions
  1318 between nat and other types, which supersedes the older libraries
  1319 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1320 
  1321   Constants:
  1322   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1323   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1324   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1325   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1326   Countable.pair_encode           ~> prod_encode
  1327   NatIso.prod2nat                 ~> prod_encode
  1328   NatIso.nat2prod                 ~> prod_decode
  1329   NatIso.sum2nat                  ~> sum_encode
  1330   NatIso.nat2sum                  ~> sum_decode
  1331   NatIso.list2nat                 ~> list_encode
  1332   NatIso.nat2list                 ~> list_decode
  1333   NatIso.set2nat                  ~> set_encode
  1334   NatIso.nat2set                  ~> set_decode
  1335 
  1336   Lemmas:
  1337   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1338   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1339   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1340   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1341   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1342   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1343   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1344   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1345   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1346   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1347   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1348   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1349   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1350 
  1351 * Sledgehammer:
  1352   - Renamed ATP commands:
  1353     atp_info     ~> sledgehammer running_atps
  1354     atp_kill     ~> sledgehammer kill_atps
  1355     atp_messages ~> sledgehammer messages
  1356     atp_minimize ~> sledgehammer minimize
  1357     print_atps   ~> sledgehammer available_atps
  1358     INCOMPATIBILITY.
  1359   - Added user's manual ("isabelle doc sledgehammer").
  1360   - Added option syntax and "sledgehammer_params" to customize
  1361     Sledgehammer's behavior.  See the manual for details.
  1362   - Modified the Isar proof reconstruction code so that it produces
  1363     direct proofs rather than proofs by contradiction.  (This feature
  1364     is still experimental.)
  1365   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1366     full-typed mode.
  1367   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1368 
  1369 * Nitpick:
  1370   - Added and implemented "binary_ints" and "bits" options.
  1371   - Added "std" option and implemented support for nonstandard models.
  1372   - Added and implemented "finitize" option to improve the precision
  1373     of infinite datatypes based on a monotonicity analysis.
  1374   - Added support for quotient types.
  1375   - Added support for "specification" and "ax_specification"
  1376     constructs.
  1377   - Added support for local definitions (for "function" and
  1378     "termination" proofs).
  1379   - Added support for term postprocessors.
  1380   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1381   - Improved efficiency of "destroy_constrs" optimization.
  1382   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1383     record getters.
  1384   - Fixed soundness bug related to higher-order constructors.
  1385   - Fixed soundness bug when "full_descrs" is enabled.
  1386   - Improved precision of set constructs.
  1387   - Added "atoms" option.
  1388   - Added cache to speed up repeated Kodkod invocations on the same
  1389     problems.
  1390   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1391     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1392     "SAT4J_Light".  INCOMPATIBILITY.
  1393   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1394     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1395   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1396 
  1397 * Method "induct" now takes instantiations of the form t, where t is not
  1398   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1399   If this is not intended, t has to be enclosed in parentheses.
  1400   By default, the equalities generated by definitional instantiations
  1401   are pre-simplified, which may cause parameters of inductive cases
  1402   to disappear, or may even delete some of the inductive cases.
  1403   Use "induct (no_simp)" instead of "induct" to restore the old
  1404   behaviour. The (no_simp) option is also understood by the "cases"
  1405   and "nominal_induct" methods, which now perform pre-simplification, too.
  1406   INCOMPATIBILITY.
  1407 
  1408 
  1409 *** HOLCF ***
  1410 
  1411 * Variable names in lemmas generated by the domain package have
  1412 changed; the naming scheme is now consistent with the HOL datatype
  1413 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1414 
  1415 * The domain package no longer defines the function "foo_copy" for
  1416 recursive domain "foo".  The reach lemma is now stated directly in
  1417 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1418 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1419 
  1420 * Most definedness lemmas generated by the domain package (previously
  1421 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1422 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1423 Proofs that used definedness lemmas as intro rules may break,
  1424 potential INCOMPATIBILITY.
  1425 
  1426 * Induction and casedist rules generated by the domain package now
  1427 declare proper case_names (one called "bottom", and one named for each
  1428 constructor).  INCOMPATIBILITY.
  1429 
  1430 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1431 rules are generated for each domain, INCOMPATIBILITY.
  1432 
  1433   foo_bar.reach       ~> foo.reach  bar.reach
  1434   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1435 
  1436 * Some lemmas generated by the domain package have been renamed for
  1437 consistency with the datatype package, INCOMPATIBILITY.
  1438 
  1439   foo.ind        ~> foo.induct
  1440   foo.finite_ind ~> foo.finite_induct
  1441   foo.coind      ~> foo.coinduct
  1442   foo.casedist   ~> foo.exhaust
  1443   foo.exhaust    ~> foo.nchotomy
  1444 
  1445 * For consistency with other definition packages, the fixrec package
  1446 now generates qualified theorem names, INCOMPATIBILITY.
  1447 
  1448   foo_simps  ~> foo.simps
  1449   foo_unfold ~> foo.unfold
  1450   foo_induct ~> foo.induct
  1451 
  1452 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1453 method and internal fixrec proofs now use the default simpset instead.
  1454 INCOMPATIBILITY.
  1455 
  1456 * The "contlub" predicate has been removed.  Proof scripts should use
  1457 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1458 
  1459 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1460 
  1461 * The constants cpair, cfst, and csnd have been removed in favor of
  1462 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1463 
  1464 
  1465 *** ML ***
  1466 
  1467 * Antiquotations for basic formal entities:
  1468 
  1469     @{class NAME}         -- type class
  1470     @{class_syntax NAME}  -- syntax representation of the above
  1471 
  1472     @{type_name NAME}     -- logical type
  1473     @{type_abbrev NAME}   -- type abbreviation
  1474     @{nonterminal NAME}   -- type of concrete syntactic category
  1475     @{type_syntax NAME}   -- syntax representation of any of the above
  1476 
  1477     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1478     @{const_abbrev NAME}  -- abbreviated constant
  1479     @{const_syntax NAME}  -- syntax representation of any of the above
  1480 
  1481 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1482 syntax constant (cf. 'syntax' command).
  1483 
  1484 * Antiquotation @{make_string} inlines a function to print arbitrary
  1485 values similar to the ML toplevel.  The result is compiler dependent
  1486 and may fall back on "?" in certain situations.
  1487 
  1488 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1489 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1490 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1491 not work with the asynchronous Isar document model.
  1492 
  1493 * Configuration options now admit dynamic default values, depending on
  1494 the context or even global references.
  1495 
  1496 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1497 uses an efficient external library if available (for Poly/ML).
  1498 
  1499 * Renamed some important ML structures, while keeping the old names
  1500 for some time as aliases within the structure Legacy:
  1501 
  1502   OuterKeyword  ~>  Keyword
  1503   OuterLex      ~>  Token
  1504   OuterParse    ~>  Parse
  1505   OuterSyntax   ~>  Outer_Syntax
  1506   PrintMode     ~>  Print_Mode
  1507   SpecParse     ~>  Parse_Spec
  1508   ThyInfo       ~>  Thy_Info
  1509   ThyLoad       ~>  Thy_Load
  1510   ThyOutput     ~>  Thy_Output
  1511   TypeInfer     ~>  Type_Infer
  1512 
  1513 Note that "open Legacy" simplifies porting of sources, but forgetting
  1514 to remove it again will complicate porting again in the future.
  1515 
  1516 * Most operations that refer to a global context are named
  1517 accordingly, e.g. Simplifier.global_context or
  1518 ProofContext.init_global.  There are some situations where a global
  1519 context actually works, but under normal circumstances one needs to
  1520 pass the proper local context through the code!
  1521 
  1522 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1523 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1524 Pretty.pp argument to merge, which is absent in the standard
  1525 Theory_Data version.
  1526 
  1527 * Sorts.certify_sort and derived "cert" operations for types and terms
  1528 no longer minimize sorts.  Thus certification at the boundary of the
  1529 inference kernel becomes invariant under addition of class relations,
  1530 which is an important monotonicity principle.  Sorts are now minimized
  1531 in the syntax layer only, at the boundary between the end-user and the
  1532 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1533 explicitly in rare situations.
  1534 
  1535 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1536 emphasize that this is in no way a standard operation.
  1537 INCOMPATIBILITY.
  1538 
  1539 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1540 usual for resolution.  Rare INCOMPATIBILITY.
  1541 
  1542 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1543 to emphasize that these only work in a global situation (which is
  1544 quite rare).
  1545 
  1546 * Curried take and drop in library.ML; negative length is interpreted
  1547 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1548 
  1549 * Proof terms: type substitutions on proof constants now use canonical
  1550 order of type variables.  INCOMPATIBILITY for tools working with proof
  1551 terms.
  1552 
  1553 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1554 may no longer carry premises.  User-level specifications are
  1555 transformed accordingly by Thm.add_axiom/add_def.
  1556 
  1557 
  1558 *** System ***
  1559 
  1560 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1561 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1562 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1563 
  1564 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1565 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1566 respectively.
  1567 
  1568 * Old lib/scripts/polyml-platform is superseded by the
  1569 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1570 variant, even on a 64 bit machine.  The following example setting
  1571 prefers 64 bit if available:
  1572 
  1573   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1574 
  1575 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1576 Isabelle/Scala layer for advanced prover interaction and integration.
  1577 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1578 component.
  1579 
  1580 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1581 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1582 similar to the default assignment of the document preparation system
  1583 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1584 provides some operations for direct access to the font without asking
  1585 the user for manual installation.
  1586 
  1587 
  1588 
  1589 New in Isabelle2009-1 (December 2009)
  1590 -------------------------------------
  1591 
  1592 *** General ***
  1593 
  1594 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1595 one backslash should be used, even in ML sources.
  1596 
  1597 
  1598 *** Pure ***
  1599 
  1600 * Locale interpretation propagates mixins along the locale hierarchy.
  1601 The currently only available mixins are the equations used to map
  1602 local definitions to terms of the target domain of an interpretation.
  1603 
  1604 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1605 loc" to print all interpretations of locale "loc" in the theory.
  1606 Interpretations in proofs are not shown.
  1607 
  1608 * Thoroughly revised locales tutorial.  New section on conditional
  1609 interpretation.
  1610 
  1611 * On instantiation of classes, remaining undefined class parameters
  1612 are formally declared.  INCOMPATIBILITY.
  1613 
  1614 
  1615 *** Document preparation ***
  1616 
  1617 * New generalized style concept for printing terms: @{foo (style) ...}
  1618 instead of @{foo_style style ...}  (old form is still retained for
  1619 backward compatibility).  Styles can be also applied for
  1620 antiquotations prop, term_type and typeof.
  1621 
  1622 
  1623 *** HOL ***
  1624 
  1625 * New proof method "smt" for a combination of first-order logic with
  1626 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1627 fixed-size bitvectors; there is also basic support for higher-order
  1628 features (esp. lambda abstractions).  It is an incomplete decision
  1629 procedure based on external SMT solvers using the oracle mechanism;
  1630 for the SMT solver Z3, this method is proof-producing.  Certificates
  1631 are provided to avoid calling the external solvers solely for
  1632 re-checking proofs.  Due to a remote SMT service there is no need for
  1633 installing SMT solvers locally.  See src/HOL/SMT.
  1634 
  1635 * New commands to load and prove verification conditions generated by
  1636 the Boogie program verifier or derived systems (e.g. the Verifying C
  1637 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1638 
  1639 * New counterexample generator tool 'nitpick' based on the Kodkod
  1640 relational model finder.  See src/HOL/Tools/Nitpick and
  1641 src/HOL/Nitpick_Examples.
  1642 
  1643 * New commands 'code_pred' and 'values' to invoke the predicate
  1644 compiler and to enumerate values of inductive predicates.
  1645 
  1646 * A tabled implementation of the reflexive transitive closure.
  1647 
  1648 * New implementation of quickcheck uses generic code generator;
  1649 default generators are provided for all suitable HOL types, records
  1650 and datatypes.  Old quickcheck can be re-activated importing theory
  1651 Library/SML_Quickcheck.
  1652 
  1653 * New testing tool Mirabelle for automated proof tools.  Applies
  1654 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1655 every proof step in a theory.  To be used in batch mode via the
  1656 "mirabelle" utility.
  1657 
  1658 * New proof method "sos" (sum of squares) for nonlinear real
  1659 arithmetic (originally due to John Harison). It requires theory
  1660 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1661 works well in practice on quantifier-free real arithmetic with +, -,
  1662 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1663 inequalities between polynomials.  It makes use of external
  1664 semidefinite programming solvers.  Method "sos" generates a
  1665 certificate that can be pasted into the proof thus avoiding the need
  1666 to call an external tool every time the proof is checked.  See
  1667 src/HOL/Library/Sum_Of_Squares.
  1668 
  1669 * New method "linarith" invokes existing linear arithmetic decision
  1670 procedure only.
  1671 
  1672 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1673 
  1674 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1675 Causes full type information to be output to the ATPs.  This slows
  1676 ATPs down considerably but eliminates a source of unsound "proofs"
  1677 that fail later.
  1678 
  1679 * New method "metisFT": A version of metis that uses full type
  1680 information in order to avoid failures of proof reconstruction.
  1681 
  1682 * New evaluator "approximate" approximates an real valued term using
  1683 the same method as the approximation method.
  1684 
  1685 * Method "approximate" now supports arithmetic expressions as
  1686 boundaries of intervals and implements interval splitting and Taylor
  1687 series expansion.
  1688 
  1689 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1690 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1691 
  1692 * New theory SupInf of the supremum and infimum operators for sets of
  1693 reals.
  1694 
  1695 * New theory Probability, which contains a development of measure
  1696 theory, eventually leading to Lebesgue integration and probability.
  1697 
  1698 * Extended Multivariate Analysis to include derivation and Brouwer's
  1699 fixpoint theorem.
  1700 
  1701 * Reorganization of number theory, INCOMPATIBILITY:
  1702   - new number theory development for nat and int, in theories Divides
  1703     and GCD as well as in new session Number_Theory
  1704   - some constants and facts now suffixed with _nat and _int
  1705     accordingly
  1706   - former session NumberTheory now named Old_Number_Theory, including
  1707     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1708   - moved theory Pocklington from src/HOL/Library to
  1709     src/HOL/Old_Number_Theory
  1710 
  1711 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1712 lcm of finite and infinite sets. It is shown that they form a complete
  1713 lattice.
  1714 
  1715 * Class semiring_div requires superclass no_zero_divisors and proof of
  1716 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1717 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1718 generalized to class semiring_div, subsuming former theorems
  1719 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1720 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1721 INCOMPATIBILITY.
  1722 
  1723 * Refinements to lattice classes and sets:
  1724   - less default intro/elim rules in locale variant, more default
  1725     intro/elim rules in class variant: more uniformity
  1726   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1727     le_inf_iff
  1728   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1729     sup_aci)
  1730   - renamed ACI to inf_sup_aci
  1731   - new class "boolean_algebra"
  1732   - class "complete_lattice" moved to separate theory
  1733     "Complete_Lattice"; corresponding constants (and abbreviations)
  1734     renamed and with authentic syntax:
  1735     Set.Inf ~>    Complete_Lattice.Inf
  1736     Set.Sup ~>    Complete_Lattice.Sup
  1737     Set.INFI ~>   Complete_Lattice.INFI
  1738     Set.SUPR ~>   Complete_Lattice.SUPR
  1739     Set.Inter ~>  Complete_Lattice.Inter
  1740     Set.Union ~>  Complete_Lattice.Union
  1741     Set.INTER ~>  Complete_Lattice.INTER
  1742     Set.UNION ~>  Complete_Lattice.UNION
  1743   - authentic syntax for
  1744     Set.Pow
  1745     Set.image
  1746   - mere abbreviations:
  1747     Set.empty               (for bot)
  1748     Set.UNIV                (for top)
  1749     Set.inter               (for inf, formerly Set.Int)
  1750     Set.union               (for sup, formerly Set.Un)
  1751     Complete_Lattice.Inter  (for Inf)
  1752     Complete_Lattice.Union  (for Sup)
  1753     Complete_Lattice.INTER  (for INFI)
  1754     Complete_Lattice.UNION  (for SUPR)
  1755   - object-logic definitions as far as appropriate
  1756 
  1757 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1758 Un_subset_iff are explicitly deleted as default simp rules; then also
  1759 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1760 deleted to achieve the desired effect.
  1761 
  1762 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1763 rules by default any longer; the same applies to min_max.inf_absorb1
  1764 etc.  INCOMPATIBILITY.
  1765 
  1766 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1767 pred_set_conv by default.  INCOMPATIBILITY.
  1768 
  1769 * Power operations on relations and functions are now one dedicated
  1770 constant "compow" with infix syntax "^^".  Power operation on
  1771 multiplicative monoids retains syntax "^" and is now defined generic
  1772 in class power.  INCOMPATIBILITY.
  1773 
  1774 * Relation composition "R O S" now has a more standard argument order:
  1775 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1776 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1777 break, since the O_assoc rule was not rewritten like this.  Fix using
  1778 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1779 
  1780 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1781 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1782 INCOMPATIBILITY.
  1783 
  1784 * Most rules produced by inductive and datatype package have mandatory
  1785 prefixes.  INCOMPATIBILITY.
  1786 
  1787 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1788 the attribute of the same name.  Each of the theorems in the list
  1789 DERIV_intros assumes composition with an additional function and
  1790 matches a variable to the derivative, which has to be solved by the
  1791 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1792 of most elementary terms.  Former Maclauren.DERIV_tac and
  1793 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1794 INCOMPATIBILITY.
  1795 
  1796 * Code generator attributes follow the usual underscore convention:
  1797     code_unfold     replaces    code unfold
  1798     code_post       replaces    code post
  1799     etc.
  1800   INCOMPATIBILITY.
  1801 
  1802 * Renamed methods:
  1803     sizechange -> size_change
  1804     induct_scheme -> induction_schema
  1805   INCOMPATIBILITY.
  1806 
  1807 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1808 INCOMPATIBILITY, use "undefined" directly.
  1809 
  1810 * Renamed theorems:
  1811     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1812     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1813     Suc_plus1 -> Suc_eq_plus1
  1814     *anti_sym -> *antisym*
  1815     vector_less_eq_def -> vector_le_def
  1816   INCOMPATIBILITY.
  1817 
  1818 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1819 INCOMPATIBILITY.
  1820 
  1821 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1822 INCOMPATIBILITY.
  1823 
  1824 
  1825 *** HOLCF ***
  1826 
  1827 * Theory Representable defines a class "rep" of domains that are
  1828 representable (via an ep-pair) in the universal domain type "udom".
  1829 Instances are provided for all type constructors defined in HOLCF.
  1830 
  1831 * The 'new_domain' command is a purely definitional version of the
  1832 domain package, for representable domains.  Syntax is identical to the
  1833 old domain package.  The 'new_domain' package also supports indirect
  1834 recursion using previously-defined type constructors.  See
  1835 src/HOLCF/ex/New_Domain.thy for examples.
  1836 
  1837 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1838 on the left-hand side of an equation, and then performs
  1839 simplification.  Rewriting is done using rules declared with the
  1840 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1841 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1842 
  1843 * The pattern-match compiler in 'fixrec' can now handle constructors
  1844 with HOL function types.  Pattern-match combinators for the Pair
  1845 constructor are pre-configured.
  1846 
  1847 * The 'fixrec' package now produces better fixed-point induction rules
  1848 for mutually-recursive definitions:  Induction rules have conclusions
  1849 of the form "P foo bar" instead of "P <foo, bar>".
  1850 
  1851 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1852 been renamed to "below".  The name "below" now replaces "less" in many
  1853 theorem names.  (Legacy theorem names using "less" are still supported
  1854 as well.)
  1855 
  1856 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1857 patterns can be used to generate strictness rules, or to make
  1858 functions more strict (much like the bang-patterns supported by the
  1859 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1860 examples.
  1861 
  1862 
  1863 *** ML ***
  1864 
  1865 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1866 errors and run-time exceptions, including detailed source positions.
  1867 
  1868 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1869 identified entries, with some additional information such as source
  1870 position, logical grouping etc.
  1871 
  1872 * Theory and context data is now introduced by the simplified and
  1873 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1874 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1875 copy operation) is still available for some time.
  1876 
  1877 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1878 provides a high-level programming interface to synchronized state
  1879 variables with atomic update.  This works via pure function
  1880 application within a critical section -- its runtime should be as
  1881 short as possible; beware of deadlocks if critical code is nested,
  1882 either directly or indirectly via other synchronized variables!
  1883 
  1884 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1885 wraps raw ML references, explicitly indicating their non-thread-safe
  1886 behaviour.  The Isar toplevel keeps this structure open, to
  1887 accommodate Proof General as well as quick and dirty interactive
  1888 experiments with references.
  1889 
  1890 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1891 parallel tactical reasoning.
  1892 
  1893 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1894 are similar to SUBPROOF, but are slightly more flexible: only the
  1895 specified parts of the subgoal are imported into the context, and the
  1896 body tactic may introduce new subgoals and schematic variables.
  1897 
  1898 * Old tactical METAHYPS, which does not observe the proof context, has
  1899 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1900 or Subgoal.FOCUS etc.
  1901 
  1902 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1903 functors have their own ML name space there is no point to mark them
  1904 separately.)  Minor INCOMPATIBILITY.
  1905 
  1906 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1907 
  1908 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1909 INCOMPATIBILITY.
  1910 
  1911 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1912 mode, which avoids critical setmp.
  1913 
  1914 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1915 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1916 Attrib/Method.setup introduced in Isabelle2009.
  1917 
  1918 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1919 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1920 last resort.  INCOMPATIBILITY.
  1921 
  1922 * Display.pretty_thm now requires a proper context (cf. former
  1923 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1924 or even Display.pretty_thm_without_context as last resort.
  1925 INCOMPATIBILITY.
  1926 
  1927 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1928 Syntax.pretty_typ/term directly, preferably with proper context
  1929 instead of global theory.
  1930 
  1931 
  1932 *** System ***
  1933 
  1934 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1935 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1936 usedir option -q.
  1937 
  1938 * Support for additional "Isabelle components" via etc/components, see
  1939 also the system manual.
  1940 
  1941 * The isabelle makeall tool now operates on all components with
  1942 IsaMakefile, not just hardwired "logics".
  1943 
  1944 * Removed "compress" option from isabelle-process and isabelle usedir;
  1945 this is always enabled.
  1946 
  1947 * Discontinued support for Poly/ML 4.x versions.
  1948 
  1949 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  1950 on a given logic image.  This requires the lighttpd webserver and is
  1951 currently supported on Linux only.
  1952 
  1953 
  1954 
  1955 New in Isabelle2009 (April 2009)
  1956 --------------------------------
  1957 
  1958 *** General ***
  1959 
  1960 * Simplified main Isabelle executables, with less surprises on
  1961 case-insensitive file-systems (such as Mac OS).
  1962 
  1963   - The main Isabelle tool wrapper is now called "isabelle" instead of
  1964     "isatool."
  1965 
  1966   - The former "isabelle" alias for "isabelle-process" has been
  1967     removed (should rarely occur to regular users).
  1968 
  1969   - The former "isabelle-interface" and its alias "Isabelle" have been
  1970     removed (interfaces are now regular Isabelle tools).
  1971 
  1972 Within scripts and make files, the Isabelle environment variables
  1973 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  1974 respectively.  (The latter are still available as legacy feature.)
  1975 
  1976 The old isabelle-interface wrapper could react in confusing ways if
  1977 the interface was uninstalled or changed otherwise.  Individual
  1978 interface tool configuration is now more explicit, see also the
  1979 Isabelle system manual.  In particular, Proof General is now available
  1980 via "isabelle emacs".
  1981 
  1982 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  1983 purge installed copies of Isabelle executables and re-run "isabelle
  1984 install -p ...", or use symlinks.
  1985 
  1986 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  1987 old ~/isabelle, which was slightly non-standard and apt to cause
  1988 surprises on case-insensitive file-systems (such as Mac OS).
  1989 
  1990 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  1991 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  1992 care is required when using older releases of Isabelle.  Note that
  1993 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  1994 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  1995 
  1996 * Proofs of fully specified statements are run in parallel on
  1997 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  1998 a regular 4-core machine, if the initial heap space is made reasonably
  1999 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  2000 
  2001 * The main reference manuals ("isar-ref", "implementation", and
  2002 "system") have been updated and extended.  Formally checked references
  2003 as hyperlinks are now available uniformly.
  2004 
  2005 
  2006 *** Pure ***
  2007 
  2008 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  2009 respects.  The most important changes are listed below.  See the
  2010 Tutorial on Locales ("locales" manual) for details.
  2011 
  2012 - In locale expressions, instantiation replaces renaming.  Parameters
  2013 must be declared in a for clause.  To aid compatibility with previous
  2014 parameter inheritance, in locale declarations, parameters that are not
  2015 'touched' (instantiation position "_" or omitted) are implicitly added
  2016 with their syntax at the beginning of the for clause.
  2017 
  2018 - Syntax from abbreviations and definitions in locales is available in
  2019 locale expressions and context elements.  The latter is particularly
  2020 useful in locale declarations.
  2021 
  2022 - More flexible mechanisms to qualify names generated by locale
  2023 expressions.  Qualifiers (prefixes) may be specified in locale
  2024 expressions, and can be marked as mandatory (syntax: "name!:") or
  2025 optional (syntax "name?:").  The default depends for plain "name:"
  2026 depends on the situation where a locale expression is used: in
  2027 commands 'locale' and 'sublocale' prefixes are optional, in
  2028 'interpretation' and 'interpret' prefixes are mandatory.  The old
  2029 implicit qualifiers derived from the parameter names of a locale are
  2030 no longer generated.
  2031 
  2032 - Command "sublocale l < e" replaces "interpretation l < e".  The
  2033 instantiation clause in "interpretation" and "interpret" (square
  2034 brackets) is no longer available.  Use locale expressions.
  2035 
  2036 - When converting proof scripts, mandatory qualifiers in
  2037 'interpretation' and 'interpret' should be retained by default, even
  2038 if this is an INCOMPATIBILITY compared to former behavior.  In the
  2039 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  2040 in locale expressions range over a single locale instance only.
  2041 
  2042 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  2043 In existing theorem specifications replace the includes element by the
  2044 respective context elements of the included locale, omitting those
  2045 that are already present in the theorem specification.  Multiple
  2046 assume elements of a locale should be replaced by a single one
  2047 involving the locale predicate.  In the proof body, declarations (most
  2048 notably theorems) may be regained by interpreting the respective
  2049 locales in the proof context as required (command "interpret").
  2050 
  2051 If using "includes" in replacement of a target solely because the
  2052 parameter types in the theorem are not as general as in the target,
  2053 consider declaring a new locale with additional type constraints on
  2054 the parameters (context element "constrains").
  2055 
  2056 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2057 
  2058 - Locale interpretation commands no longer attempt to simplify goal.
  2059 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2060 methods intro_locales and unfold_locales to clarify.
  2061 
  2062 - Locale interpretation commands no longer accept interpretation
  2063 attributes.  INCOMPATIBILITY.
  2064 
  2065 * Class declaration: so-called "base sort" must not be given in import
  2066 list any longer, but is inferred from the specification.  Particularly
  2067 in HOL, write
  2068 
  2069     class foo = ...
  2070 
  2071 instead of
  2072 
  2073     class foo = type + ...
  2074 
  2075 * Class target: global versions of theorems stemming do not carry a
  2076 parameter prefix any longer.  INCOMPATIBILITY.
  2077 
  2078 * Class 'instance' command no longer accepts attached definitions.
  2079 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2080 
  2081 * Recovered hiding of consts, which was accidentally broken in
  2082 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2083 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2084 
  2085 * Slightly more coherent Pure syntax, with updated documentation in
  2086 isar-ref manual.  Removed locales meta_term_syntax and
  2087 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2088 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2089 directly in regular applications.
  2090 
  2091 * There is a new syntactic category "float_const" for signed decimal
  2092 fractions (e.g. 123.45 or -123.45).
  2093 
  2094 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2095 interface with 'setup' command instead.
  2096 
  2097 * Command 'local_setup' is similar to 'setup', but operates on a local
  2098 theory context.
  2099 
  2100 * The 'axiomatization' command now only works within a global theory
  2101 context.  INCOMPATIBILITY.
  2102 
  2103 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2104 hypotheses.  Sorts required in the course of reasoning need to be
  2105 covered by the constraints in the initial statement, completed by the
  2106 type instance information of the background theory.  Non-trivial sort
  2107 hypotheses, which rarely occur in practice, may be specified via
  2108 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2109 
  2110   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2111 
  2112 The result contains an implicit sort hypotheses as before --
  2113 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2114 normalization.
  2115 
  2116 * Generalized Isar history, with support for linear undo, direct state
  2117 addressing etc.
  2118 
  2119 * Changed defaults for unify configuration options:
  2120 
  2121   unify_trace_bound = 50 (formerly 25)
  2122   unify_search_bound = 60 (formerly 30)
  2123 
  2124 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2125 
  2126   a) On theory merge, the last set of code equations for a particular
  2127      constant is taken (in accordance with the policy applied by other
  2128      parts of the code generator framework).
  2129 
  2130   b) Code equations stemming from explicit declarations (e.g. code
  2131      attribute) gain priority over default code equations stemming
  2132      from definition, primrec, fun etc.
  2133 
  2134 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2135 
  2136 * Unified theorem tables for both code generators.  Thus [code
  2137 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2138 
  2139 * Command 'find_consts' searches for constants based on type and name
  2140 patterns, e.g.
  2141 
  2142     find_consts "_ => bool"
  2143 
  2144 By default, matching is against subtypes, but it may be restricted to
  2145 the whole type.  Searching by name is possible.  Multiple queries are
  2146 conjunctive and queries may be negated by prefixing them with a
  2147 hyphen:
  2148 
  2149     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2150 
  2151 * New 'find_theorems' criterion "solves" matches theorems that
  2152 directly solve the current goal (modulo higher-order unification).
  2153 
  2154 * Auto solve feature for main theorem statements: whenever a new goal
  2155 is stated, "find_theorems solves" is called; any theorems that could
  2156 solve the lemma directly are listed as part of the goal state.
  2157 Cf. associated options in Proof General Isabelle settings menu,
  2158 enabled by default, with reasonable timeout for pathological cases of
  2159 higher-order unification.
  2160 
  2161 
  2162 *** Document preparation ***
  2163 
  2164 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2165 demanding keyword 'by' and supporting the full method expression
  2166 syntax just like the Isar command 'by'.
  2167 
  2168 
  2169 *** HOL ***
  2170 
  2171 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2172 points Main and Complex_Main remain as before.
  2173 
  2174 * Logic image HOL-Plain provides a minimal HOL with the most important
  2175 tools available (inductive, datatype, primrec, ...).  This facilitates
  2176 experimentation and tool development.  Note that user applications
  2177 (and library theories) should never refer to anything below theory
  2178 Main, as before.
  2179 
  2180 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2181 experimentation due to shorter build times.
  2182 
  2183 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2184 were previously part of former HOL-Complex.  Entry point Hyperreal
  2185 remains valid, but theories formerly using Complex_Main should now use
  2186 new entry point Hypercomplex.
  2187 
  2188 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2189 Posix processes.  Avoids potentially expensive forking of the ML
  2190 process.  New thread-based implementation also works on non-Unix
  2191 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2192 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2193 commands are covered in the isar-ref manual.
  2194 
  2195 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2196 sledgehammer without local ATP installation (Vampire etc.). Other
  2197 provers may be included via suitable ML wrappers, see also
  2198 src/HOL/ATP_Linkup.thy.
  2199 
  2200 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2201 menu.
  2202 
  2203 * The metis method no longer fails because the theorem is too trivial
  2204 (contains the empty clause).
  2205 
  2206 * The metis method now fails in the usual manner, rather than raising
  2207 an exception, if it determines that it cannot prove the theorem.
  2208 
  2209 * Method "coherent" implements a prover for coherent logic (see also
  2210 src/Tools/coherent.ML).
  2211 
  2212 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2213 "undefined" is the right choice to replace "arbitrary", though
  2214 logically there is no difference.  INCOMPATIBILITY.
  2215 
  2216 * Command "value" now integrates different evaluation mechanisms.  The
  2217 result of the first successful evaluation mechanism is printed.  In
  2218 square brackets a particular named evaluation mechanisms may be
  2219 specified (currently, [SML], [code] or [nbe]).  See further
  2220 src/HOL/ex/Eval_Examples.thy.
  2221 
  2222 * Normalization by evaluation now allows non-leftlinear equations.
  2223 Declare with attribute [code nbe].
  2224 
  2225 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2226 as the structured Isar versions "cases" and "induct", cf. the
  2227 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2228 are now presented as a list of individual projections
  2229 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2230 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2231 rare situations a different rule is selected --- notably nested tuple
  2232 elimination instead of former prod.exhaust: use explicit (case_tac t
  2233 rule: prod.exhaust) here.
  2234 
  2235 * Attributes "cases", "induct", "coinduct" support "del" option.
  2236 
  2237 * Removed fact "case_split_thm", which duplicates "case_split".
  2238 
  2239 * The option datatype has been moved to a new theory Option.  Renamed
  2240 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2241 
  2242 * New predicate "strict_mono" classifies strict functions on partial
  2243 orders.  With strict functions on linear orders, reasoning about
  2244 (in)equalities is facilitated by theorems "strict_mono_eq",
  2245 "strict_mono_less_eq" and "strict_mono_less".
  2246 
  2247 * Some set operations are now proper qualified constants with
  2248 authentic syntax.  INCOMPATIBILITY:
  2249 
  2250     op Int ~>   Set.Int
  2251     op Un ~>    Set.Un
  2252     INTER ~>    Set.INTER
  2253     UNION ~>    Set.UNION
  2254     Inter ~>    Set.Inter
  2255     Union ~>    Set.Union
  2256     {} ~>       Set.empty
  2257     UNIV ~>     Set.UNIV
  2258 
  2259 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2260 theory Set.
  2261 
  2262 * Auxiliary class "itself" has disappeared -- classes without any
  2263 parameter are treated as expected by the 'class' command.
  2264 
  2265 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2266 
  2267 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2268 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2269 
  2270 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2271 method "approximation".  It proves formulas on real values by using
  2272 interval arithmetic.  In the formulas are also the transcendental
  2273 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2274 allowed. For examples see
  2275 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2276 
  2277 * Theory "Reflection" now resides in HOL/Library.
  2278 
  2279 * Entry point to Word library now simply named "Word".
  2280 INCOMPATIBILITY.
  2281 
  2282 * Made source layout more coherent with logical distribution
  2283 structure:
  2284 
  2285     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2286     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2287     src/HOL/Library/GCD.thy ~> src/HOL/
  2288     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2289     src/HOL/Library/Parity.thy ~> src/HOL/
  2290     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2291     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2292     src/HOL/Real/Lubs.thy ~> src/HOL/
  2293     src/HOL/Real/PReal.thy ~> src/HOL/
  2294     src/HOL/Real/Rational.thy ~> src/HOL/
  2295     src/HOL/Real/RComplete.thy ~> src/HOL/
  2296     src/HOL/Real/RealDef.thy ~> src/HOL/
  2297     src/HOL/Real/RealPow.thy ~> src/HOL/
  2298     src/HOL/Real/Real.thy ~> src/HOL/
  2299     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2300     src/HOL/Complex/Complex.thy ~> src/HOL/
  2301     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2302     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2303     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2304     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2305     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2306     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2307     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2308     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2309     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2310     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2311     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2312     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2313     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2314     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2315     src/HOL/Real/Float ~> src/HOL/Library/
  2316     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2317     src/HOL/Real/RealVector.thy ~> src/HOL/
  2318 
  2319     src/HOL/arith_data.ML ~> src/HOL/Tools
  2320     src/HOL/hologic.ML ~> src/HOL/Tools
  2321     src/HOL/simpdata.ML ~> src/HOL/Tools
  2322     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2323     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2324     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2325     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2326     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2327     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2328     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2329 
  2330     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2331     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2332     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2333     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2334     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2335     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2336 
  2337 * If methods "eval" and "evaluation" encounter a structured proof
  2338 state with !!/==>, only the conclusion is evaluated to True (if
  2339 possible), avoiding strange error messages.
  2340 
  2341 * Method "sizechange" automates termination proofs using (a
  2342 modification of) the size-change principle.  Requires SAT solver.  See
  2343 src/HOL/ex/Termination.thy for examples.
  2344 
  2345 * Simplifier: simproc for let expressions now unfolds if bound
  2346 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2347 
  2348 * Method "arith": Linear arithmetic now ignores all inequalities when
  2349 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2350 
  2351 * New attribute "arith" for facts that should always be used
  2352 automatically by arithmetic. It is intended to be used locally in
  2353 proofs, e.g.
  2354 
  2355   assumes [arith]: "x > 0"
  2356 
  2357 Global usage is discouraged because of possible performance impact.
  2358 
  2359 * New classes "top" and "bot" with corresponding operations "top" and
  2360 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2361 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2362 
  2363 * Changed definition lemma "less_fun_def" in order to provide an
  2364 instance for preorders on functions; use lemma "less_le" instead.
  2365 INCOMPATIBILITY.
  2366 
  2367 * Theory Orderings: class "wellorder" moved here, with explicit
  2368 induction rule "less_induct" as assumption.  For instantiation of
  2369 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2370 INCOMPATIBILITY.
  2371 
  2372 * Theory Orderings: added class "preorder" as superclass of "order".
  2373 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2374 etc. slightly changed.  Some theorems named order_class.* now named
  2375 preorder_class.*.
  2376 
  2377 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2378 "diag" to "Id_on".
  2379 
  2380 * Theory Finite_Set: added a new fold combinator of type
  2381 
  2382   ('a => 'b => 'b) => 'b => 'a set => 'b
  2383 
  2384 Occasionally this is more convenient than the old fold combinator
  2385 which is now defined in terms of the new one and renamed to
  2386 fold_image.
  2387 
  2388 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2389 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2390 extended with further lemmas!).  At the moment both still exist but
  2391 the former will disappear at some point.
  2392 
  2393 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2394 class recpower.  Type-specific simp rules for various recpower types
  2395 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2396 
  2397 rat_power_0    -> power_0
  2398 rat_power_Suc  -> power_Suc
  2399 realpow_0      -> power_0
  2400 realpow_Suc    -> power_Suc
  2401 complexpow_0   -> power_0
  2402 complexpow_Suc -> power_Suc
  2403 power_poly_0   -> power_0
  2404 power_poly_Suc -> power_Suc
  2405 
  2406 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2407 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2408 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2409 of lemmas from Divides has been generalized from nat to class
  2410 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2411 renames resulting from duplicate elimination:
  2412 
  2413     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2414     zero_dvd_iff ~>         dvd_0_left_iff
  2415     dvd_0 ~>                dvd_0_right
  2416     DIVISION_BY_ZERO_DIV ~> div_by_0
  2417     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2418     mult_div ~>             div_mult_self2_is_id
  2419     mult_mod ~>             mod_mult_self2_is_0
  2420 
  2421 * Theory IntDiv: removed many lemmas that are instances of class-based
  2422 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2423 rename old lemmas as follows:
  2424 
  2425 dvd_diff               -> nat_dvd_diff
  2426 dvd_zminus_iff         -> dvd_minus_iff
  2427 mod_add1_eq            -> mod_add_eq
  2428 mod_mult1_eq           -> mod_mult_right_eq
  2429 mod_mult1_eq'          -> mod_mult_left_eq
  2430 mod_mult_distrib_mod   -> mod_mult_eq
  2431 nat_mod_add_left_eq    -> mod_add_left_eq
  2432 nat_mod_add_right_eq   -> mod_add_right_eq
  2433 nat_mod_div_trivial    -> mod_div_trivial
  2434 nat_mod_mod_trivial    -> mod_mod_trivial
  2435 zdiv_zadd_self1        -> div_add_self1
  2436 zdiv_zadd_self2        -> div_add_self2
  2437 zdiv_zmult_self1       -> div_mult_self2_is_id
  2438 zdiv_zmult_self2       -> div_mult_self1_is_id
  2439 zdvd_triv_left         -> dvd_triv_left
  2440 zdvd_triv_right        -> dvd_triv_right
  2441 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2442 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2443 zmod_zadd_left_eq      -> mod_add_left_eq
  2444 zmod_zadd_right_eq     -> mod_add_right_eq
  2445 zmod_zadd_self1        -> mod_add_self1
  2446 zmod_zadd_self2        -> mod_add_self2
  2447 zmod_zadd1_eq          -> mod_add_eq
  2448 zmod_zdiff1_eq         -> mod_diff_eq
  2449 zmod_zdvd_zmod         -> mod_mod_cancel
  2450 zmod_zmod_cancel       -> mod_mod_cancel
  2451 zmod_zmult_self1       -> mod_mult_self2_is_0
  2452 zmod_zmult_self2       -> mod_mult_self1_is_0
  2453 zmod_1                 -> mod_by_1
  2454 zdiv_1                 -> div_by_1
  2455 zdvd_abs1              -> abs_dvd_iff
  2456 zdvd_abs2              -> dvd_abs_iff
  2457 zdvd_refl              -> dvd_refl
  2458 zdvd_trans             -> dvd_trans
  2459 zdvd_zadd              -> dvd_add
  2460 zdvd_zdiff             -> dvd_diff
  2461 zdvd_zminus_iff        -> dvd_minus_iff
  2462 zdvd_zminus2_iff       -> minus_dvd_iff
  2463 zdvd_zmultD            -> dvd_mult_right
  2464 zdvd_zmultD2           -> dvd_mult_left
  2465 zdvd_zmult_mono        -> mult_dvd_mono
  2466 zdvd_0_right           -> dvd_0_right
  2467 zdvd_0_left            -> dvd_0_left_iff
  2468 zdvd_1_left            -> one_dvd
  2469 zminus_dvd_iff         -> minus_dvd_iff
  2470 
  2471 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2472 
  2473 * The real numbers offer decimal input syntax: 12.34 is translated
  2474 into 1234/10^2. This translation is not reversed upon output.
  2475 
  2476 * Theory Library/Polynomial defines an abstract type 'a poly of
  2477 univariate polynomials with coefficients of type 'a.  In addition to
  2478 the standard ring operations, it also supports div and mod.  Code
  2479 generation is also supported, using list-style constructors.
  2480 
  2481 * Theory Library/Inner_Product defines a class of real_inner for real
  2482 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2483 => real.  Class real_inner is a subclass of real_normed_vector from
  2484 theory RealVector.
  2485 
  2486 * Theory Library/Product_Vector provides instances for the product
  2487 type 'a * 'b of several classes from RealVector and Inner_Product.
  2488 Definitions of addition, subtraction, scalar multiplication, norms,
  2489 and inner products are included.
  2490 
  2491 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2492 addition to the field operations, numerals and case syntax are also
  2493 supported.
  2494 
  2495 * Theory Library/Diagonalize provides constructive version of Cantor's
  2496 first diagonalization argument.
  2497 
  2498 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2499 zlcm (for int); carried together from various gcd/lcm developements in
  2500 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2501 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2502 may recover tupled syntax as follows:
  2503 
  2504     hide (open) const gcd
  2505     abbreviation gcd where
  2506       "gcd == (%(a, b). GCD.gcd a b)"
  2507     notation (output)
  2508       GCD.gcd ("gcd '(_, _')")
  2509 
  2510 The same works for lcm, zgcd, zlcm.
  2511 
  2512 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2513 instantiations for algebraic structures.  Removed some duplicate
  2514 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2515 
  2516 * ML antiquotation @{code} takes a constant as argument and generates
  2517 corresponding code in background and inserts name of the corresponding
  2518 resulting ML value/function/datatype constructor binding in place.
  2519 All occurrences of @{code} with a single ML block are generated
  2520 simultaneously.  Provides a generic and safe interface for
  2521 instrumentalizing code generation.  See
  2522 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2523 In future you ought to refrain from ad-hoc compiling generated SML
  2524 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2525 cannot refer to constants for which user-defined serializations are
  2526 set.  Refer to the corresponding ML counterpart directly in that
  2527 cases.
  2528 
  2529 * Command 'rep_datatype': instead of theorem names the command now
  2530 takes a list of terms denoting the constructors of the type to be
  2531 represented as datatype.  The characteristic theorems have to be
  2532 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2533 have disappeared in favour of existing ones:
  2534 
  2535     unit_induct                 ~> unit.induct
  2536     prod_induct                 ~> prod.induct
  2537     sum_induct                  ~> sum.induct
  2538     Suc_Suc_eq                  ~> nat.inject
  2539     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2540 
  2541 
  2542 *** HOL-Algebra ***
  2543 
  2544 * New locales for orders and lattices where the equivalence relation
  2545 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2546 locales use a record structure with field eq for the equivalence.
  2547 
  2548 * New theory of factorial domains.
  2549 
  2550 * Units_l_inv and Units_r_inv are now simp rules by default.
  2551 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2552 and/or r_inv will now also require deletion of these lemmas.
  2553 
  2554 * Renamed the following theorems, INCOMPATIBILITY:
  2555 
  2556 UpperD ~> Upper_memD
  2557 LowerD ~> Lower_memD
  2558 least_carrier ~> least_closed
  2559 greatest_carrier ~> greatest_closed
  2560 greatest_Lower_above ~> greatest_Lower_below
  2561 one_zero ~> carrier_one_zero
  2562 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2563 
  2564 
  2565 *** HOL-Nominal ***
  2566 
  2567 * Nominal datatypes can now contain type-variables.
  2568 
  2569 * Commands 'nominal_inductive' and 'equivariance' work with local
  2570 theory targets.
  2571 
  2572 * Nominal primrec can now works with local theory targets and its
  2573 specification syntax now conforms to the general format as seen in
  2574 'inductive' etc.
  2575 
  2576 * Method "perm_simp" honours the standard simplifier attributes
  2577 (no_asm), (no_asm_use) etc.
  2578 
  2579 * The new predicate #* is defined like freshness, except that on the
  2580 left hand side can be a set or list of atoms.
  2581 
  2582 * Experimental command 'nominal_inductive2' derives strong induction
  2583 principles for inductive definitions.  In contrast to
  2584 'nominal_inductive', which can only deal with a fixed number of
  2585 binders, it can deal with arbitrary expressions standing for sets of
  2586 atoms to be avoided.  The only inductive definition we have at the
  2587 moment that needs this generalisation is the typing rule for Lets in
  2588 the algorithm W:
  2589 
  2590  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2591  -----------------------------------------------------------------
  2592          Gamma |- Let x be t1 in t2 : T2
  2593 
  2594 In this rule one wants to avoid all the binders that are introduced by
  2595 "close Gamma T1".  We are looking for other examples where this
  2596 feature might be useful.  Please let us know.
  2597 
  2598 
  2599 *** HOLCF ***
  2600 
  2601 * Reimplemented the simplification procedure for proving continuity
  2602 subgoals.  The new simproc is extensible; users can declare additional
  2603 continuity introduction rules with the attribute [cont2cont].
  2604 
  2605 * The continuity simproc now uses a different introduction rule for
  2606 solving continuity subgoals on terms with lambda abstractions.  In
  2607 some rare cases the new simproc may fail to solve subgoals that the
  2608 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2609 Potential INCOMPATIBILITY.
  2610 
  2611 * Command 'fixrec': specification syntax now conforms to the general
  2612 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2613 examples.  INCOMPATIBILITY.
  2614 
  2615 
  2616 *** ZF ***
  2617 
  2618 * Proof of Zorn's Lemma for partial orders.
  2619 
  2620 
  2621 *** ML ***
  2622 
  2623 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2624 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2625 depends on multithreading, so timouts will not work before Poly/ML
  2626 5.2.1!
  2627 
  2628 * High-level support for concurrent ML programming, see
  2629 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2630 particularly convenient to organize independent functional
  2631 computations.  The concept of "synchronized variables" provides a
  2632 higher-order interface for components with shared state, avoiding the
  2633 delicate details of mutexes and condition variables.  (Requires
  2634 Poly/ML 5.2.1 or later.)
  2635 
  2636 * ML bindings produced via Isar commands are stored within the Isar
  2637 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2638 become thread-safe and work with undo as expected (concerning
  2639 top-level bindings, not side-effects on global references).
  2640 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2641 compiler at runtime; really global bindings need to be given outside a
  2642 theory.  (Requires Poly/ML 5.2 or later.)
  2643 
  2644 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2645 context.  Top-level ML bindings are stored within the proof context in
  2646 a purely sequential fashion, disregarding the nested proof structure.
  2647 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2648 proof.  (Requires Poly/ML 5.2 or later.)
  2649 
  2650 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2651 and Method.setup, as well as Isar commands 'attribute_setup' and
  2652 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2653 existing code accordingly, or use plain 'setup' together with old
  2654 Method.add_method.
  2655 
  2656 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2657 to 'a -> thm, while results are always tagged with an authentic oracle
  2658 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2659 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2660 accordingly.  Note that extra performance may be gained by producing
  2661 the cterm carefully, avoiding slow Thm.cterm_of.
  2662 
  2663 * Simplified interface for defining document antiquotations via
  2664 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2665 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2666 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2667 examples.
  2668 
  2669 * More systematic treatment of long names, abstract name bindings, and
  2670 name space operations.  Basic operations on qualified names have been
  2671 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2672 Long_Name.append.  Old type bstring has been mostly replaced by
  2673 abstract type binding (see structure Binding), which supports precise
  2674 qualification by packages and local theory targets, as well as proper
  2675 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2676 bstring values into Binding.name, or better pass through abstract
  2677 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2678 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2679 
  2680 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2681 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2682 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2683 
  2684 * Disposed old type and term read functions (Sign.read_def_typ,
  2685 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2686 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2687 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2688 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2689 resort for legacy applications.
  2690 
  2691 * Disposed old declarations, tactics, tactic combinators that refer to
  2692 the simpset or claset of an implicit theory (such as Addsimps,
  2693 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2694 embedded ML text, or local_simpset_of with a proper context passed as
  2695 explicit runtime argument.
  2696 
  2697 * Rules and tactics that read instantiations (read_instantiate,
  2698 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2699 context, which is required for parsing and type-checking.  Moreover,
  2700 the variables are specified as plain indexnames, not string encodings
  2701 thereof.  INCOMPATIBILITY.
  2702 
  2703 * Generic Toplevel.add_hook interface allows to analyze the result of
  2704 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2705 for theorem dependency output of transactions resulting in a new
  2706 theory state.
  2707 
  2708 * ML antiquotations: block-structured compilation context indicated by
  2709 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2710 
  2711   @{binding name}                         - basic name binding
  2712   @{let ?pat = term}                      - term abbreviation (HO matching)
  2713   @{note name = fact}                     - fact abbreviation
  2714   @{thm fact}                             - singleton fact (with attributes)
  2715   @{thms fact}                            - general fact (with attributes)
  2716   @{lemma prop by method}                 - singleton goal
  2717   @{lemma prop by meth1 meth2}            - singleton goal
  2718   @{lemma prop1 ... propN by method}      - general goal
  2719   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2720   @{lemma (open) ...}                     - open derivation
  2721 
  2722 
  2723 *** System ***
  2724 
  2725 * The Isabelle "emacs" tool provides a specific interface to invoke
  2726 Proof General / Emacs, with more explicit failure if that is not
  2727 installed (the old isabelle-interface script silently falls back on
  2728 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2729 installation location of the Proof General distribution.
  2730 
  2731 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2732 the Isabelle process into a JVM/Scala application.  See
  2733 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2734 process wrapper has been discontinued.)
  2735 
  2736 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2737 
  2738 * Various status messages (with exact source position information) are
  2739 emitted, if proper markup print mode is enabled.  This allows
  2740 user-interface components to provide detailed feedback on internal
  2741 prover operations.
  2742 
  2743 
  2744 
  2745 New in Isabelle2008 (June 2008)
  2746 -------------------------------
  2747 
  2748 *** General ***
  2749 
  2750 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2751 and updated, with formally checked references as hyperlinks.
  2752 
  2753 * Theory loader: use_thy (and similar operations) no longer set the
  2754 implicit ML context, which was occasionally hard to predict and in
  2755 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2756 provides a proper context already.
  2757 
  2758 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2759 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2760 'use' within a theory file will do the job.
  2761 
  2762 * Name space merge now observes canonical order, i.e. the second space
  2763 is inserted into the first one, while existing entries in the first
  2764 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2765 swap theory imports.
  2766 
  2767 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2768 INCOMPATIBILITY in identifier syntax etc.
  2769 
  2770 * Outer syntax: string tokens no longer admit escaped white space,
  2771 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2772 white space without escapes.
  2773 
  2774 * Outer syntax: string tokens may contain arbitrary character codes
  2775 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2776 "foo_bar".
  2777 
  2778 
  2779 *** Pure ***
  2780 
  2781 * Context-dependent token translations.  Default setup reverts locally
  2782 fixed variables, and adds hilite markup for undeclared frees.
  2783 
  2784 * Unused theorems can be found using the new command 'unused_thms'.
  2785 There are three ways of invoking it:
  2786 
  2787 (1) unused_thms
  2788      Only finds unused theorems in the current theory.
  2789 
  2790 (2) unused_thms thy_1 ... thy_n -
  2791      Finds unused theorems in the current theory and all of its ancestors,
  2792      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2793 
  2794 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2795      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2796      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2797      their ancestors.
  2798 
  2799 In order to increase the readability of the list produced by
  2800 unused_thms, theorems that have been created by a particular instance
  2801 of a theory command such as 'inductive' or 'function' are considered
  2802 to belong to the same "group", meaning that if at least one theorem in
  2803 this group is used, the other theorems in the same group are no longer
  2804 reported as unused.  Moreover, if all theorems in the group are
  2805 unused, only one theorem in the group is displayed.
  2806 
  2807 Note that proof objects have to be switched on in order for
  2808 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2809 usually the case when using Proof General with the default settings).
  2810 
  2811 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2812 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2813 duplicate fact bindings, or even accidental fact duplications.  Note
  2814 that tools may maintain dynamically scoped facts systematically, using
  2815 PureThy.add_thms_dynamic.
  2816 
  2817 * Command 'hide' now allows to hide from "fact" name space as well.
  2818 
  2819 * Eliminated destructive theorem database, simpset, claset, and
  2820 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2821 update of theories within ML code.
  2822 
  2823 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2824 INCOMPATIBILITY, object-logics depending on former Pure require
  2825 additional setup PureThy.old_appl_syntax_setup; object-logics
  2826 depending on former CPure need to refer to Pure.
  2827 
  2828 * Commands 'use' and 'ML' are now purely functional, operating on
  2829 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2830 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2831 INCOMPATIBILITY.
  2832 
  2833 * Command 'setup': discontinued implicit version with ML reference.
  2834 
  2835 * Instantiation target allows for simultaneous specification of class
  2836 instance operations together with an instantiation proof.
  2837 Type-checking phase allows to refer to class operations uniformly.
  2838 See src/HOL/Complex/Complex.thy for an Isar example and
  2839 src/HOL/Library/Eval.thy for an ML example.
  2840 
  2841 * Indexing of literal facts: be more serious about including only
  2842 facts from the visible specification/proof context, but not the
  2843 background context (locale etc.).  Affects `prop` notation and method
  2844 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2845 situations.
  2846 
  2847 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2848 "(open)" option, which used to expose internal bound variables to the
  2849 proof text.
  2850 
  2851 * Isar statements: removed obsolete case "rule_context".
  2852 INCOMPATIBILITY, better use explicit fixes/assumes.
  2853 
  2854 * Locale proofs: default proof step now includes 'unfold_locales';
  2855 hence 'proof' without argument may be used to unfold locale
  2856 predicates.
  2857 
  2858 
  2859 *** Document preparation ***
  2860 
  2861 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2862 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2863 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2864 spot); renamed link color from "darkblue" to "linkcolor" (default
  2865 value unchanged, can be redefined via \definecolor); no longer sets
  2866 "a4paper" option (unnecessary or even intrusive).
  2867 
  2868 * Antiquotation @{lemma A method} proves proposition A by the given
  2869 method (either a method name or a method name plus (optional) method
  2870 arguments in parentheses) and prints A just like @{prop A}.
  2871 
  2872 
  2873 *** HOL ***
  2874 
  2875 * New primrec package.  Specification syntax conforms in style to
  2876 definition/function/....  No separate induction rule is provided.  The
  2877 "primrec" command distinguishes old-style and new-style specifications
  2878 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2879 When adjusting theories, beware: constants stemming from new-style
  2880 primrec specifications have authentic syntax.
  2881 
  2882 * Metis prover is now an order of magnitude faster, and also works
  2883 with multithreading.
  2884 
  2885 * Metis: the maximum number of clauses that can be produced from a
  2886 theorem is now given by the attribute max_clauses.  Theorems that
  2887 exceed this number are ignored, with a warning printed.
  2888 
  2889 * Sledgehammer no longer produces structured proofs by default. To
  2890 enable, declare [[sledgehammer_full = true]].  Attributes
  2891 reconstruction_modulus, reconstruction_sorts renamed
  2892 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2893 
  2894 * Method "induct_scheme" derives user-specified induction rules
  2895 from well-founded induction and completeness of patterns. This factors
  2896 out some operations that are done internally by the function package
  2897 and makes them available separately.  See
  2898 src/HOL/ex/Induction_Scheme.thy for examples.
  2899 
  2900 * More flexible generation of measure functions for termination
  2901 proofs: Measure functions can be declared by proving a rule of the
  2902 form "is_measure f" and giving it the [measure_function] attribute.
  2903 The "is_measure" predicate is logically meaningless (always true), and
  2904 just guides the heuristic.  To find suitable measure functions, the
  2905 termination prover sets up the goal "is_measure ?f" of the appropriate
  2906 type and generates all solutions by prolog-style backwards proof using
  2907 the declared rules.
  2908 
  2909 This setup also deals with rules like 
  2910 
  2911   "is_measure f ==> is_measure (list_size f)"
  2912 
  2913 which accommodates nested datatypes that recurse through lists.
  2914 Similar rules are predeclared for products and option types.
  2915 
  2916 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2917 
  2918   INCOMPATIBILITIES:
  2919 
  2920   - Definitions of overloaded constants on sets have to be replaced by
  2921     definitions on => and bool.
  2922 
  2923   - Some definitions of overloaded operators on sets can now be proved
  2924     using the definitions of the operators on => and bool.  Therefore,
  2925     the following theorems have been renamed:
  2926 
  2927       subset_def   -> subset_eq
  2928       psubset_def  -> psubset_eq
  2929       set_diff_def -> set_diff_eq
  2930       Compl_def    -> Compl_eq
  2931       Sup_set_def  -> Sup_set_eq
  2932       Inf_set_def  -> Inf_set_eq
  2933       sup_set_def  -> sup_set_eq
  2934       inf_set_def  -> inf_set_eq
  2935 
  2936   - Due to the incompleteness of the HO unification algorithm, some
  2937     rules such as subst may require manual instantiation, if some of
  2938     the unknowns in the rule is a set.
  2939 
  2940   - Higher order unification and forward proofs:
  2941     The proof pattern
  2942 
  2943       have "P (S::'a set)" <...>
  2944       then have "EX S. P S" ..
  2945 
  2946     no longer works (due to the incompleteness of the HO unification
  2947     algorithm) and must be replaced by the pattern
  2948 
  2949       have "EX S. P S"
  2950       proof
  2951         show "P S" <...>
  2952       qed
  2953 
  2954   - Calculational reasoning with subst (or similar rules):
  2955     The proof pattern
  2956 
  2957       have "P (S::'a set)" <...>
  2958       also have "S = T" <...>
  2959       finally have "P T" .
  2960 
  2961     no longer works (for similar reasons as the previous example) and
  2962     must be replaced by something like
  2963 
  2964       have "P (S::'a set)" <...>
  2965       moreover have "S = T" <...>
  2966       ultimately have "P T" by simp
  2967 
  2968   - Tactics or packages written in ML code:
  2969     Code performing pattern matching on types via
  2970 
  2971       Type ("set", [T]) => ...
  2972 
  2973     must be rewritten. Moreover, functions like strip_type or
  2974     binder_types no longer return the right value when applied to a
  2975     type of the form
  2976 
  2977       T1 => ... => Tn => U => bool
  2978 
  2979     rather than
  2980 
  2981       T1 => ... => Tn => U set
  2982 
  2983 * Merged theories Wellfounded_Recursion, Accessible_Part and
  2984 Wellfounded_Relations to theory Wellfounded.
  2985 
  2986 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  2987 
  2988 * Class finite no longer treats UNIV as class parameter.  Use class
  2989 enum from theory Library/Enum instead to achieve a similar effect.
  2990 INCOMPATIBILITY.
  2991 
  2992 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  2993 and "Cons".  INCOMPATIBILITY.
  2994 
  2995 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  2996 Potential INCOMPATIBILITY.
  2997 
  2998 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  2999 injective_fst_snd removed, use split_eta and prod_eqI instead.
  3000 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  3001 
  3002 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  3003 the same name in theory Orderings:
  3004 
  3005   less_trans
  3006   less_linear
  3007   le_imp_less_or_eq
  3008   le_less_trans
  3009   less_le_trans
  3010   less_not_sym
  3011   less_asym
  3012 
  3013 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  3014 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  3015 and different variable names.
  3016 
  3017 * Library/Option_ord.thy: Canonical order on option type.
  3018 
  3019 * Library/RBT.thy: Red-black trees, an efficient implementation of
  3020 finite maps.
  3021 
  3022 * Library/Countable.thy: Type class for countable types.
  3023 
  3024 * Theory Int: The representation of numerals has changed.  The infix
  3025 operator BIT and the bit datatype with constructors B0 and B1 have
  3026 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  3027 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  3028 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  3029 accordingly.
  3030 
  3031 * Theory Nat: definition of <= and < on natural numbers no longer
  3032 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  3033 le_def and less_def have disappeared.  Consider lemmas not_less
  3034 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  3035 
  3036 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  3037 (whose purpose mainly is for various fold_set functionals) have been
  3038 abandoned in favor of the existing algebraic classes
  3039 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  3040 lower_semilattice (resp. upper_semilattice) and linorder.
  3041 INCOMPATIBILITY.
  3042 
  3043 * Theory Transitive_Closure: induct and cases rules now declare proper
  3044 case_names ("base" and "step").  INCOMPATIBILITY.
  3045 
  3046 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  3047 lattices.  The form set-specific version is available as
  3048 Inductive.lfp_ordinal_induct_set.
  3049 
  3050 * Renamed theorems "power.simps" to "power_int.simps".
  3051 INCOMPATIBILITY.
  3052 
  3053 * Class semiring_div provides basic abstract properties of semirings
  3054 with division and modulo operations.  Subsumes former class dvd_mod.
  3055 
  3056 * Merged theories IntDef, Numeral and IntArith into unified theory
  3057 Int.  INCOMPATIBILITY.
  3058 
  3059 * Theory Library/Code_Index: type "index" now represents natural
  3060 numbers rather than integers.  INCOMPATIBILITY.
  3061 
  3062 * New class "uminus" with operation "uminus" (split of from class
  3063 "minus" which now only has operation "minus", binary).
  3064 INCOMPATIBILITY.
  3065 
  3066 * Constants "card", "internal_split", "option_map" now with authentic
  3067 syntax.  INCOMPATIBILITY.
  3068 
  3069 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3070 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3071 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3072 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3073 Sup_set_def, le_def, less_def, option_map_def now with object
  3074 equality.  INCOMPATIBILITY.
  3075 
  3076 * Records. Removed K_record, and replaced it by pure lambda term
  3077 %x. c. The simplifier setup is now more robust against eta expansion.
  3078 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3079 
  3080 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3081 
  3082 * Library/ListVector: new theory of arithmetic vector operations.
  3083 
  3084 * Library/Order_Relation: new theory of various orderings as sets of
  3085 pairs.  Defines preorders, partial orders, linear orders and
  3086 well-orders on sets and on types.
  3087 
  3088 
  3089 *** ZF ***
  3090 
  3091 * Renamed some theories to allow to loading both ZF and HOL in the
  3092 same session:
  3093 
  3094   Datatype  -> Datatype_ZF
  3095   Inductive -> Inductive_ZF
  3096   Int       -> Int_ZF
  3097   IntDiv    -> IntDiv_ZF
  3098   Nat       -> Nat_ZF
  3099   List      -> List_ZF
  3100   Main      -> Main_ZF
  3101 
  3102 INCOMPATIBILITY: ZF theories that import individual theories below
  3103 Main might need to be adapted.  Regular theory Main is still
  3104 available, as trivial extension of Main_ZF.
  3105 
  3106 
  3107 *** ML ***
  3108 
  3109 * ML within Isar: antiquotation @{const name} or @{const
  3110 name(typargs)} produces statically-checked Const term.
  3111 
  3112 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3113 (of the same name).  Removed obsolete print command.
  3114 
  3115 * Removed obsolete "use_legacy_bindings" function.
  3116 
  3117 * The ``print mode'' is now a thread-local value derived from a global
  3118 template (the former print_mode reference), thus access becomes
  3119 non-critical.  The global print_mode reference is for session
  3120 management only; user-code should use print_mode_value,
  3121 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3122 
  3123 * Functions system/system_out provide a robust way to invoke external
  3124 shell commands, with propagation of interrupts (requires Poly/ML
  3125 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3126 
  3127 
  3128 *** System ***
  3129 
  3130 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3131 in accordance with Proof General 3.7, which prefers GNU emacs.
  3132 
  3133 * isatool tty runs Isabelle process with plain tty interaction;
  3134 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3135 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3136 
  3137 * isatool browser now works with Cygwin as well, using general
  3138 "javapath" function defined in Isabelle process environment.
  3139 
  3140 * YXML notation provides a simple and efficient alternative to
  3141 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3142 isatool yxml as described in the Isabelle system manual.
  3143 
  3144 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3145 provides general wrapper for managing an Isabelle process in a robust
  3146 fashion, with ``cooked'' output from stdin/stderr.
  3147 
  3148 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3149 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3150 
  3151 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3152 way of changing the user's settings is via
  3153 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3154 script.
  3155 
  3156 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3157 cores of the underlying machine, which is a good starting point for
  3158 optimal performance tuning.  The corresponding usedir option -M allows
  3159 "max" as an alias for "0".  WARNING: does not work on certain versions
  3160 of Mac OS (with Poly/ML 5.1).
  3161 
  3162 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3163 adverse effect of Isabelle flooding interactive front-ends (notably
  3164 ProofGeneral / XEmacs).
  3165 
  3166 
  3167 
  3168 New in Isabelle2007 (November 2007)
  3169 -----------------------------------
  3170 
  3171 *** General ***
  3172 
  3173 * More uniform information about legacy features, notably a
  3174 warning/error of "Legacy feature: ...", depending on the state of the
  3175 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3176 legacy features will disappear eventually.
  3177 
  3178 * Theory syntax: the header format ``theory A = B + C:'' has been
  3179 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3180 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3181 
  3182 * Theory syntax: the old non-Isar theory file format has been
  3183 discontinued altogether.  Note that ML proof scripts may still be used
  3184 with Isar theories; migration is usually quite simple with the ML
  3185 function use_legacy_bindings.  INCOMPATIBILITY.
  3186 
  3187 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3188 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3189 quotes.
  3190 
  3191 * Theory loader: be more serious about observing the static theory
  3192 header specifications (including optional directories), but not the
  3193 accidental file locations of previously successful loads.  The strict
  3194 update policy of former update_thy is now already performed by
  3195 use_thy, so the former has been removed; use_thys updates several
  3196 theories simultaneously, just as 'imports' within a theory header
  3197 specification, but without merging the results.  Potential
  3198 INCOMPATIBILITY: may need to refine theory headers and commands
  3199 ROOT.ML which depend on load order.
  3200 
  3201 * Theory loader: optional support for content-based file
  3202 identification, instead of the traditional scheme of full physical
  3203 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3204 (cf. the system manual).  The new scheme allows to work with
  3205 non-finished theories in persistent session images, such that source
  3206 files may be moved later on without requiring reloads.
  3207 
  3208 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3209 file (with the same base name as the theory) are considered a legacy
  3210 feature, which will disappear eventually. Even now, the theory loader
  3211 no longer maintains dependencies on such files.
  3212 
  3213 * Syntax: the scope for resolving ambiguities via type-inference is
  3214 now limited to individual terms, instead of whole simultaneous
  3215 specifications as before. This greatly reduces the complexity of the
  3216 syntax module and improves flexibility by separating parsing and
  3217 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3218 'fixes' etc.) are required in rare situations.
  3219 
  3220 * Syntax: constants introduced by new-style packages ('definition',
  3221 'abbreviation' etc.) are passed through the syntax module in
  3222 ``authentic mode''. This means that associated mixfix annotations
  3223 really stick to such constants, independently of potential name space
  3224 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3225 trees are represented slightly differently, may need to adapt syntax
  3226 translations accordingly. Use CONST marker in 'translations' and
  3227 @{const_syntax} antiquotation in 'parse_translation' etc.
  3228 
  3229 * Legacy goal package: reduced interface to the bare minimum required
  3230 to keep existing proof scripts running.  Most other user-level
  3231 functions are now part of the OldGoals structure, which is *not* open
  3232 by default (consider isatool expandshort before open OldGoals).
  3233 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3234 these tend to cause confusion about the actual goal (!) context being
  3235 used here, which is not necessarily the same as the_context().
  3236 
  3237 * Command 'find_theorems': supports "*" wild-card in "name:"
  3238 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3239 support a specific search form (see ProofGeneral/CHANGES).
  3240 
  3241 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3242 by default, which means that "prems" (and also "fixed variables") are
  3243 suppressed from proof state output.  Note that the ProofGeneral
  3244 settings mechanism allows to change and save options persistently, but
  3245 older versions of Isabelle will fail to start up if a negative prems
  3246 limit is imposed.
  3247 
  3248 * Local theory targets may be specified by non-nested blocks of
  3249 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3250 contain definitions, theorems etc., including any derived mechanism
  3251 that has been implemented on top of these primitives.  This concept
  3252 generalizes the existing ``theorem (in ...)'' towards more versatility
  3253 and scalability.
  3254 
  3255 * Proof General interface: proper undo of final 'end' command;
  3256 discontinued Isabelle/classic mode (ML proof scripts).
  3257 
  3258 
  3259 *** Document preparation ***
  3260 
  3261 * Added antiquotation @{theory name} which prints the given name,
  3262 after checking that it refers to a valid ancestor theory in the
  3263 current context.
  3264 
  3265 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3266 check the given source text as ML type/structure, printing verbatim.
  3267 
  3268 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3269 "c args == rhs" given in the current context.  (Any number of
  3270 arguments may be given on the LHS.)
  3271 
  3272 
  3273 *** Pure ***
  3274 
  3275 * The 'class' package offers a combination of axclass and locale to
  3276 achieve Haskell-like type classes in Isabelle.  Definitions and
  3277 theorems within a class context produce both relative results (with
  3278 implicit parameters according to the locale context), and polymorphic
  3279 constants with qualified polymorphism (according to the class
  3280 context).  Within the body context of a 'class' target, a separate
  3281 syntax layer ("user space type system") takes care of converting
  3282 between global polymorphic consts and internal locale representation.
  3283 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3284 "isatool doc classes" provides a tutorial.
  3285 
  3286 * Generic code generator framework allows to generate executable
  3287 code for ML and Haskell (including Isabelle classes).  A short usage
  3288 sketch:
  3289 
  3290     internal compilation:
  3291         export_code <list of constants (term syntax)> in SML
  3292     writing SML code to a file:
  3293         export_code <list of constants (term syntax)> in SML <filename>
  3294     writing OCaml code to a file:
  3295         export_code <list of constants (term syntax)> in OCaml <filename>
  3296     writing Haskell code to a bunch of files:
  3297         export_code <list of constants (term syntax)> in Haskell <filename>
  3298 
  3299     evaluating closed propositions to True/False using code generation:
  3300         method ``eval''
  3301 
  3302 Reasonable default setup of framework in HOL.
  3303 
  3304 Theorem attributs for selecting and transforming function equations theorems:
  3305 
  3306     [code fun]:        select a theorem as function equation for a specific constant
  3307     [code fun del]:    deselect a theorem as function equation for a specific constant
  3308     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3309     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3310 
  3311 User-defined serializations (target in {SML, OCaml, Haskell}):
  3312 
  3313     code_const <and-list of constants (term syntax)>
  3314       {(target) <and-list of const target syntax>}+
  3315 
  3316     code_type <and-list of type constructors>
  3317       {(target) <and-list of type target syntax>}+
  3318 
  3319     code_instance <and-list of instances>
  3320       {(target)}+
  3321         where instance ::= <type constructor> :: <class>
  3322 
  3323     code_class <and_list of classes>
  3324       {(target) <and-list of class target syntax>}+
  3325         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3326 
  3327 code_instance and code_class only are effective to target Haskell.
  3328 
  3329 For example usage see src/HOL/ex/Codegenerator.thy and
  3330 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3331 generation from Isabelle/HOL theories is available via "isatool doc
  3332 codegen".
  3333 
  3334 * Code generator: consts in 'consts_code' Isar commands are now
  3335 referred to by usual term syntax (including optional type
  3336 annotations).
  3337 
  3338 * Command 'no_translations' removes translation rules from theory
  3339 syntax.
  3340 
  3341 * Overloaded definitions are now actually checked for acyclic
  3342 dependencies.  The overloading scheme is slightly more general than
  3343 that of Haskell98, although Isabelle does not demand an exact
  3344 correspondence to type class and instance declarations.
  3345 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3346 exotic versions of overloading -- at the discretion of the user!
  3347 
  3348 Polymorphic constants are represented via type arguments, i.e. the
  3349 instantiation that matches an instance against the most general
  3350 declaration given in the signature.  For example, with the declaration
  3351 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3352 as c(nat).  Overloading is essentially simultaneous structural
  3353 recursion over such type arguments.  Incomplete specification patterns
  3354 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3355 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3356 Command 'print_theory' outputs the normalized system of recursive
  3357 equations, see section "definitions".
  3358 
  3359 * Configuration options are maintained within the theory or proof
  3360 context (with name and type bool/int/string), providing a very simple
  3361 interface to a poor-man's version of general context data.  Tools may
  3362 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3363 these values using Config.get etc.  Users may change options via an
  3364 associated attribute of the same name.  This form of context
  3365 declaration works particularly well with commands 'declare' or
  3366 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3367 very easy to avoid global references, which would not observe Isar
  3368 toplevel undo/redo and fail to work with multithreading.
  3369 
  3370 Various global ML references of Pure and HOL have been turned into
  3371 configuration options:
  3372 
  3373   Unify.search_bound		unify_search_bound
  3374   Unify.trace_bound		unify_trace_bound
  3375   Unify.trace_simp		unify_trace_simp
  3376   Unify.trace_types		unify_trace_types
  3377   Simplifier.simp_depth_limit	simp_depth_limit
  3378   Blast.depth_limit		blast_depth_limit
  3379   DatatypeProp.dtK		datatype_distinctness_limit
  3380   fast_arith_neq_limit  	fast_arith_neq_limit
  3381   fast_arith_split_limit	fast_arith_split_limit
  3382 
  3383 * Named collections of theorems may be easily installed as context
  3384 data using the functor NamedThmsFun (see also
  3385 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3386 attributes; there is also a toplevel print command.  This facility is
  3387 just a common case of general context data, which is the preferred way
  3388 for anything more complex than just a list of facts in canonical
  3389 order.
  3390 
  3391 * Isar: command 'declaration' augments a local theory by generic
  3392 declaration functions written in ML.  This enables arbitrary content
  3393 being added to the context, depending on a morphism that tells the
  3394 difference of the original declaration context wrt. the application
  3395 context encountered later on.
  3396 
  3397 * Isar: proper interfaces for simplification procedures.  Command
  3398 'simproc_setup' declares named simprocs (with match patterns, and body
  3399 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3400 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3401 
  3402 * Isar: an extra pair of brackets around attribute declarations
  3403 abbreviates a theorem reference involving an internal dummy fact,
  3404 which will be ignored later --- only the effect of the attribute on
  3405 the background context will persist.  This form of in-place
  3406 declarations is particularly useful with commands like 'declare' and
  3407 'using', for example ``have A using [[simproc a]] by simp''.
  3408 
  3409 * Isar: method "assumption" (and implicit closing of subproofs) now
  3410 takes simple non-atomic goal assumptions into account: after applying
  3411 an assumption as a rule the resulting subgoals are solved by atomic
  3412 assumption steps.  This is particularly useful to finish 'obtain'
  3413 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3414 without referring to the original premise "!!x. P x ==> thesis" in the
  3415 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3416 more permissive.
  3417 
  3418 * Isar: implicit use of prems from the Isar proof context is
  3419 considered a legacy feature.  Common applications like ``have A .''
  3420 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3421 referencing facts explicitly here improves readability and
  3422 maintainability of proof texts.
  3423 
  3424 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3425 the obtained context from the course of reasoning!  For example:
  3426 
  3427   assume "EX x y. A x & B y"   -- "any previous fact"
  3428   then guess x and y by clarify
  3429 
  3430 This technique is potentially adventurous, depending on the facts and
  3431 proof tools being involved here.
  3432 
  3433 * Isar: known facts from the proof context may be specified as literal
  3434 propositions, using ASCII back-quote syntax.  This works wherever
  3435 named facts used to be allowed so far, in proof commands, proof
  3436 methods, attributes etc.  Literal facts are retrieved from the context
  3437 according to unification of type and term parameters.  For example,
  3438 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3439 theorems in the current context, then these are valid literal facts:
  3440 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3441 
  3442 There is also a proof method "fact" which does the same composition
  3443 for explicit goal states, e.g. the following proof texts coincide with
  3444 certain special cases of literal facts:
  3445 
  3446   have "A" by fact                 ==  note `A`
  3447   have "A ==> B" by fact           ==  note `A ==> B`
  3448   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3449   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3450 
  3451 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3452 outer syntax.  Thus symbolic identifiers may be used without
  3453 additional white space in declarations like this: ``assume *: A''.
  3454 
  3455 * Isar: 'print_facts' prints all local facts of the current context,
  3456 both named and unnamed ones.
  3457 
  3458 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3459 
  3460   def x == "t" and y == "u"
  3461 
  3462 * Isar: added command 'unfolding', which is structurally similar to
  3463 'using', but affects both the goal state and facts by unfolding given
  3464 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3465 'unfolded' attribute may be replaced by first-class proof text.
  3466 
  3467 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3468 and command 'unfolding' now all support object-level equalities
  3469 (potentially conditional).  The underlying notion of rewrite rule is
  3470 analogous to the 'rule_format' attribute, but *not* that of the
  3471 Simplifier (which is usually more generous).
  3472 
  3473 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3474 premises of a theorem by n. Useful in conjunction with drule.
  3475 
  3476 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3477 method expression within a sandbox consisting of the first N
  3478 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3479 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3480 simplifies all new goals that emerge from applying rule foo to the
  3481 originally first one.
  3482 
  3483 * Isar: schematic goals are no longer restricted to higher-order
  3484 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3485 expected.
  3486 
  3487 * Isar: the conclusion of a long theorem statement is now either
  3488 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3489 (essentially a disjunction of cases with local parameters and
  3490 assumptions).  The latter allows to express general elimination rules
  3491 adequately; in this notation common elimination rules look like this:
  3492 
  3493   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3494     assumes "EX x. P x"
  3495     obtains x where "P x"
  3496 
  3497   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3498     assumes "A & B"
  3499     obtains A and B
  3500 
  3501   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3502     assumes "A | B"
  3503     obtains
  3504       A
  3505     | B
  3506 
  3507 The subsequent classical rules even refer to the formal "thesis"
  3508 explicitly:
  3509 
  3510   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3511     obtains "~ thesis"
  3512 
  3513   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3514     obtains "thesis ==> something"
  3515 
  3516 The actual proof of an 'obtains' statement is analogous to that of the
  3517 Isar proof element 'obtain', only that there may be several cases.
  3518 Optional case names may be specified in parentheses; these will be
  3519 available both in the present proof and as annotations in the
  3520 resulting rule, for later use with the 'cases' method (cf. attribute
  3521 case_names).
  3522 
  3523 * Isar: the assumptions of a long theorem statement are available as
  3524 "assms" fact in the proof context.  This is more appropriate than the
  3525 (historical) "prems", which refers to all assumptions of the current
  3526 context, including those from the target locale, proof body etc.
  3527 
  3528 * Isar: 'print_statement' prints theorems from the current theory or
  3529 proof context in long statement form, according to the syntax of a
  3530 top-level lemma.
  3531 
  3532 * Isar: 'obtain' takes an optional case name for the local context
  3533 introduction rule (default "that").
  3534 
  3535 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3536 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3537 to occur.
  3538 
  3539 * Pure: syntax "CONST name" produces a fully internalized constant
  3540 according to the current context.  This is particularly useful for
  3541 syntax translations that should refer to internal constant
  3542 representations independently of name spaces.
  3543 
  3544 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3545 instead of "FOO ". This allows multiple binder declarations to coexist
  3546 in the same context.  INCOMPATIBILITY.
  3547 
  3548 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3549 primitive that also works in a locale context (both for constants and
  3550 fixed variables). Type declaration and internal syntactic representation
  3551 of given constants retrieved from the context. Likewise, the
  3552 'no_notation' command allows to remove given syntax annotations from the
  3553 current context.
  3554 
  3555 * Isar/locales: new derived specification elements 'axiomatization',
  3556 'definition', 'abbreviation', which support type-inference, admit
  3557 object-level specifications (equality, equivalence).  See also the
  3558 isar-ref manual.  Examples:
  3559 
  3560   axiomatization
  3561     eq  (infix "===" 50) where
  3562     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3563 
  3564   definition "f x y = x + y + 1"
  3565   definition g where "g x = f x x"
  3566 
  3567   abbreviation
  3568     neq  (infix "=!=" 50) where
  3569     "x =!= y == ~ (x === y)"
  3570 
  3571 These specifications may be also used in a locale context.  Then the
  3572 constants being introduced depend on certain fixed parameters, and the
  3573 constant name is qualified by the locale base name.  An internal
  3574 abbreviation takes care for convenient input and output, making the
  3575 parameters implicit and using the original short name.  See also
  3576 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3577 entities from a monomorphic theory.
  3578 
  3579 Presently, abbreviations are only available 'in' a target locale, but
  3580 not inherited by general import expressions.  Also note that
  3581 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3582 'translations' in common applications.  The "no_abbrevs" print mode
  3583 prevents folding of abbreviations in term output.
  3584 
  3585 Concrete syntax is attached to specified constants in internal form,
  3586 independently of name spaces.  The parse tree representation is
  3587 slightly different -- use 'notation' instead of raw 'syntax', and
  3588 'translations' with explicit "CONST" markup to accommodate this.
  3589 
  3590 * Pure/Isar: unified syntax for new-style specification mechanisms
  3591 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3592 full type inference and dummy patterns ("_").  For example:
  3593 
  3594   definition "K x _ = x"
  3595 
  3596   inductive conj for A B
  3597   where "A ==> B ==> conj A B"
  3598 
  3599 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3600 the current context.  Print mode "no_abbrevs" prevents inversion of
  3601 abbreviations on output.
  3602 
  3603 * Isar/locales: improved parameter handling: use of locales "var" and
  3604 "struct" no longer necessary; - parameter renamings are no longer
  3605 required to be injective.  For example, this allows to define
  3606 endomorphisms as locale endom = homom mult mult h.
  3607 
  3608 * Isar/locales: changed the way locales with predicates are defined.
  3609 Instead of accumulating the specification, the imported expression is
  3610 now an interpretation.  INCOMPATIBILITY: different normal form of
  3611 locale expressions.  In particular, in interpretations of locales with
  3612 predicates, goals repesenting already interpreted fragments are not
  3613 removed automatically.  Use methods `intro_locales' and
  3614 `unfold_locales'; see below.
  3615 
  3616 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3617 provide backward reasoning on locales predicates.  The methods are
  3618 aware of interpretations and discharge corresponding goals.
  3619 `intro_locales' is less aggressive then `unfold_locales' and does not
  3620 unfold predicates to assumptions.
  3621 
  3622 * Isar/locales: the order in which locale fragments are accumulated
  3623 has changed.  This enables to override declarations from fragments due
  3624 to interpretations -- for example, unwanted simp rules.
  3625 
  3626 * Isar/locales: interpretation in theories and proof contexts has been
  3627 extended.  One may now specify (and prove) equations, which are
  3628 unfolded in interpreted theorems.  This is useful for replacing
  3629 defined concepts (constants depending on locale parameters) by
  3630 concepts already existing in the target context.  Example:
  3631 
  3632   interpretation partial_order ["op <= :: [int, int] => bool"]
  3633     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3634 
  3635 Typically, the constant `partial_order.less' is created by a
  3636 definition specification element in the context of locale
  3637 partial_order.
  3638 
  3639 * Method "induct": improved internal context management to support
  3640 local fixes and defines on-the-fly. Thus explicit meta-level
  3641 connectives !!  and ==> are rarely required anymore in inductive goals
  3642 (using object-logic connectives for this purpose has been long
  3643 obsolete anyway). Common proof patterns are explained in
  3644 src/HOL/Induct/Common_Patterns.thy, see also
  3645 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3646 examples.
  3647 
  3648 * Method "induct": improved handling of simultaneous goals. Instead of
  3649 introducing object-level conjunction, the statement is now split into
  3650 several conclusions, while the corresponding symbolic cases are nested
  3651 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3652 see src/HOL/Induct/Common_Patterns.thy, for example.
  3653 
  3654 * Method "induct": mutual induction rules are now specified as a list
  3655 of rule sharing the same induction cases. HOL packages usually provide
  3656 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3657 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3658 mutual induction rules differently, i.e. like this:
  3659 
  3660   (induct rule: foo_bar.inducts)
  3661   (induct set: foo bar)
  3662   (induct pred: foo bar)
  3663   (induct type: foo bar)
  3664 
  3665 The ML function ProjectRule.projections turns old-style rules into the
  3666 new format.
  3667 
  3668 * Method "coinduct": dual of induction, see
  3669 src/HOL/Library/Coinductive_List.thy for various examples.
  3670 
  3671 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3672 considered a legacy feature.
  3673 
  3674 * Attribute "symmetric" produces result with standardized schematic
  3675 variables (index 0).  Potential INCOMPATIBILITY.
  3676 
  3677 * Simplifier: by default the simplifier trace only shows top level
  3678 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3679 default. Thus there is less danger of being flooded by the trace. The
  3680 trace indicates where parts have been suppressed.
  3681   
  3682 * Provers/classical: removed obsolete classical version of elim_format
  3683 attribute; classical elim/dest rules are now treated uniformly when
  3684 manipulating the claset.
  3685 
  3686 * Provers/classical: stricter checks to ensure that supplied intro,
  3687 dest and elim rules are well-formed; dest and elim rules must have at
  3688 least one premise.
  3689 
  3690 * Provers/classical: attributes dest/elim/intro take an optional
  3691 weight argument for the rule (just as the Pure versions).  Weights are
  3692 ignored by automated tools, but determine the search order of single
  3693 rule steps.
  3694 
  3695 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3696 where the body does not mention the bound variable.  Note that dummy
  3697 patterns implicitly depend on their context of bounds, which makes
  3698 "{_. _}" match any set comprehension as expected.  Potential
  3699 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3700 constant "_idtdummy" in the binding position.
  3701 
  3702 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3703 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3704 for example "A -> B" => "Pi A (%_. B)".
  3705 
  3706 * Pure: 'class_deps' command visualizes the subclass relation, using
  3707 the graph browser tool.
  3708 
  3709 * Pure: 'print_theory' now suppresses certain internal declarations by
  3710 default; use '!' option for full details.
  3711 
  3712 
  3713 *** HOL ***
  3714 
  3715 * Method "metis" proves goals by applying the Metis general-purpose
  3716 resolution prover (see also http://gilith.com/software/metis/).
  3717 Examples are in the directory MetisExamples.  WARNING: the
  3718 Isabelle/HOL-Metis integration does not yet work properly with
  3719 multi-threading.
  3720   
  3721 * Command 'sledgehammer' invokes external automatic theorem provers as
  3722 background processes.  It generates calls to the "metis" method if
  3723 successful. These can be pasted into the proof.  Users do not have to
  3724 wait for the automatic provers to return.  WARNING: does not really
  3725 work with multi-threading.
  3726 
  3727 * New "auto_quickcheck" feature tests outermost goal statements for
  3728 potential counter-examples.  Controlled by ML references
  3729 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3730 5000 milliseconds).  Fails silently if statements is outside of
  3731 executable fragment, or any other codgenerator problem occurs.
  3732 
  3733 * New constant "undefined" with axiom "undefined x = undefined".
  3734 
  3735 * Added class "HOL.eq", allowing for code generation with polymorphic
  3736 equality.
  3737 
  3738 * Some renaming of class constants due to canonical name prefixing in
  3739 the new 'class' package:
  3740 
  3741     HOL.abs ~> HOL.abs_class.abs
  3742     HOL.divide ~> HOL.divide_class.divide
  3743     0 ~> HOL.zero_class.zero
  3744     1 ~> HOL.one_class.one
  3745     op + ~> HOL.plus_class.plus
  3746     op - ~> HOL.minus_class.minus
  3747     uminus ~> HOL.minus_class.uminus
  3748     op * ~> HOL.times_class.times
  3749     op < ~> HOL.ord_class.less
  3750     op <= > HOL.ord_class.less_eq
  3751     Nat.power ~> Power.power_class.power
  3752     Nat.size ~> Nat.size_class.size
  3753     Numeral.number_of ~> Numeral.number_class.number_of
  3754     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3755     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3756     Orderings.min ~> Orderings.ord_class.min
  3757     Orderings.max ~> Orderings.ord_class.max
  3758     Divides.op div ~> Divides.div_class.div
  3759     Divides.op mod ~> Divides.div_class.mod
  3760     Divides.op dvd ~> Divides.div_class.dvd
  3761 
  3762 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3763 
  3764 a) User-defined constants using any of the names "plus", "minus",
  3765 "times", "less" or "less_eq". The standard syntax translations for
  3766 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3767 names.
  3768 
  3769 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3770 INCOMPATIBILITY: use more specific names.
  3771 
  3772 c) Permutative equations (e.g. "a + b = b + a")
  3773 Since the change of names also changes the order of terms, permutative
  3774 rewrite rules may get applied in a different order. Experience shows
  3775 that this is rarely the case (only two adaptions in the whole Isabelle
  3776 distribution).  INCOMPATIBILITY: rewrite proofs
  3777 
  3778 d) ML code directly refering to constant names
  3779 This in general only affects hand-written proof tactics, simprocs and
  3780 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3781 Consider using @{const_name} antiquotation.
  3782 
  3783 * New class "default" with associated constant "default".
  3784 
  3785 * Function "sgn" is now overloaded and available on int, real, complex
  3786 (and other numeric types), using class "sgn".  Two possible defs of
  3787 sgn are given as equational assumptions in the classes sgn_if and
  3788 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3789 INCOMPATIBILITY.
  3790 
  3791 * Locale "partial_order" now unified with class "order" (cf. theory
  3792 Orderings), added parameter "less".  INCOMPATIBILITY.
  3793 
  3794 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3795 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3796 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3797 
  3798 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3799 changed order of proof goals in instance proofs.
  3800 
  3801 * The transitivity reasoner for partial and linear orders is set up
  3802 for classes "order" and "linorder".  Instances of the reasoner are available
  3803 in all contexts importing or interpreting the corresponding locales.
  3804 Method "order" invokes the reasoner separately; the reasoner
  3805 is also integrated with the Simplifier as a solver.  Diagnostic
  3806 command 'print_orders' shows the available instances of the reasoner
  3807 in the current context.
  3808 
  3809 * Localized monotonicity predicate in theory "Orderings"; integrated
  3810 lemmas max_of_mono and min_of_mono with this predicate.
  3811 INCOMPATIBILITY.
  3812 
  3813 * Formulation of theorem "dense" changed slightly due to integration
  3814 with new class dense_linear_order.
  3815 
  3816 * Uniform lattice theory development in HOL.
  3817 
  3818     constants "meet" and "join" now named "inf" and "sup"
  3819     constant "Meet" now named "Inf"
  3820 
  3821     classes "meet_semilorder" and "join_semilorder" now named
  3822       "lower_semilattice" and "upper_semilattice"
  3823     class "lorder" now named "lattice"
  3824     class "comp_lat" now named "complete_lattice"
  3825 
  3826     Instantiation of lattice classes allows explicit definitions
  3827     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3828 
  3829   INCOMPATIBILITY.  Theorem renames:
  3830 
  3831     meet_left_le            ~> inf_le1
  3832     meet_right_le           ~> inf_le2
  3833     join_left_le            ~> sup_ge1
  3834     join_right_le           ~> sup_ge2
  3835     meet_join_le            ~> inf_sup_ord
  3836     le_meetI                ~> le_infI
  3837     join_leI                ~> le_supI
  3838     le_meet                 ~> le_inf_iff
  3839     le_join                 ~> ge_sup_conv
  3840     meet_idempotent         ~> inf_idem
  3841     join_idempotent         ~> sup_idem
  3842     meet_comm               ~> inf_commute
  3843     join_comm               ~> sup_commute
  3844     meet_leI1               ~> le_infI1
  3845     meet_leI2               ~> le_infI2
  3846     le_joinI1               ~> le_supI1
  3847     le_joinI2               ~> le_supI2
  3848     meet_assoc              ~> inf_assoc
  3849     join_assoc              ~> sup_assoc
  3850     meet_left_comm          ~> inf_left_commute
  3851     meet_left_idempotent    ~> inf_left_idem
  3852     join_left_comm          ~> sup_left_commute
  3853     join_left_idempotent    ~> sup_left_idem
  3854     meet_aci                ~> inf_aci
  3855     join_aci                ~> sup_aci
  3856     le_def_meet             ~> le_iff_inf
  3857     le_def_join             ~> le_iff_sup
  3858     join_absorp2            ~> sup_absorb2
  3859     join_absorp1            ~> sup_absorb1
  3860     meet_absorp1            ~> inf_absorb1
  3861     meet_absorp2            ~> inf_absorb2
  3862     meet_join_absorp        ~> inf_sup_absorb
  3863     join_meet_absorp        ~> sup_inf_absorb
  3864     distrib_join_le         ~> distrib_sup_le
  3865     distrib_meet_le         ~> distrib_inf_le
  3866 
  3867     add_meet_distrib_left   ~> add_inf_distrib_left
  3868     add_join_distrib_left   ~> add_sup_distrib_left
  3869     is_join_neg_meet        ~> is_join_neg_inf
  3870     is_meet_neg_join        ~> is_meet_neg_sup
  3871     add_meet_distrib_right  ~> add_inf_distrib_right
  3872     add_join_distrib_right  ~> add_sup_distrib_right
  3873     add_meet_join_distribs  ~> add_sup_inf_distribs
  3874     join_eq_neg_meet        ~> sup_eq_neg_inf
  3875     meet_eq_neg_join        ~> inf_eq_neg_sup
  3876     add_eq_meet_join        ~> add_eq_inf_sup
  3877     meet_0_imp_0            ~> inf_0_imp_0
  3878     join_0_imp_0            ~> sup_0_imp_0
  3879     meet_0_eq_0             ~> inf_0_eq_0
  3880     join_0_eq_0             ~> sup_0_eq_0
  3881     neg_meet_eq_join        ~> neg_inf_eq_sup
  3882     neg_join_eq_meet        ~> neg_sup_eq_inf
  3883     join_eq_if              ~> sup_eq_if
  3884 
  3885     mono_meet               ~> mono_inf
  3886     mono_join               ~> mono_sup
  3887     meet_bool_eq            ~> inf_bool_eq
  3888     join_bool_eq            ~> sup_bool_eq
  3889     meet_fun_eq             ~> inf_fun_eq
  3890     join_fun_eq             ~> sup_fun_eq
  3891     meet_set_eq             ~> inf_set_eq
  3892     join_set_eq             ~> sup_set_eq
  3893     meet1_iff               ~> inf1_iff
  3894     meet2_iff               ~> inf2_iff
  3895     meet1I                  ~> inf1I
  3896     meet2I                  ~> inf2I
  3897     meet1D1                 ~> inf1D1
  3898     meet2D1                 ~> inf2D1
  3899     meet1D2                 ~> inf1D2
  3900     meet2D2                 ~> inf2D2
  3901     meet1E                  ~> inf1E
  3902     meet2E                  ~> inf2E
  3903     join1_iff               ~> sup1_iff
  3904     join2_iff               ~> sup2_iff
  3905     join1I1                 ~> sup1I1
  3906     join2I1                 ~> sup2I1
  3907     join1I1                 ~> sup1I1
  3908     join2I2                 ~> sup1I2
  3909     join1CI                 ~> sup1CI
  3910     join2CI                 ~> sup2CI
  3911     join1E                  ~> sup1E
  3912     join2E                  ~> sup2E
  3913 
  3914     is_meet_Meet            ~> is_meet_Inf
  3915     Meet_bool_def           ~> Inf_bool_def
  3916     Meet_fun_def            ~> Inf_fun_def
  3917     Meet_greatest           ~> Inf_greatest
  3918     Meet_lower              ~> Inf_lower
  3919     Meet_set_def            ~> Inf_set_def
  3920 
  3921     Sup_def                 ~> Sup_Inf
  3922     Sup_bool_eq             ~> Sup_bool_def
  3923     Sup_fun_eq              ~> Sup_fun_def
  3924     Sup_set_eq              ~> Sup_set_def
  3925 
  3926     listsp_meetI            ~> listsp_infI
  3927     listsp_meet_eq          ~> listsp_inf_eq
  3928 
  3929     meet_min                ~> inf_min
  3930     join_max                ~> sup_max
  3931 
  3932 * Added syntactic class "size"; overloaded constant "size" now has
  3933 type "'a::size ==> bool"
  3934 
  3935 * Internal reorganisation of `size' of datatypes: size theorems
  3936 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3937 simplification rules by default!); theorems "prod.size" now named
  3938 "*.size".
  3939 
  3940 * Class "div" now inherits from class "times" rather than "type".
  3941 INCOMPATIBILITY.
  3942 
  3943 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  3944 Linorder etc.  have disappeared; operations defined in terms of
  3945 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  3946 
  3947 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  3948 
  3949 * HOL-Word: New extensive library and type for generic, fixed size
  3950 machine words, with arithemtic, bit-wise, shifting and rotating
  3951 operations, reflection into int, nat, and bool lists, automation for
  3952 linear arithmetic (by automatic reflection into nat or int), including
  3953 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  3954 arithmetic type classes, supporting automatic simplification of
  3955 numerals on all operations.
  3956 
  3957 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  3958 
  3959 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  3960 
  3961 * Code generator library theories:
  3962   - Code_Integer represents HOL integers by big integer literals in target
  3963     languages.
  3964   - Code_Char represents HOL characters by character literals in target
  3965     languages.
  3966   - Code_Char_chr like Code_Char, but also offers treatment of character
  3967     codes; includes Code_Integer.
  3968   - Executable_Set allows to generate code for finite sets using lists.
  3969   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  3970     denominator).
  3971   - Executable_Real implements a subset of real numbers, namly those
  3972     representable by rational numbers.
  3973   - Efficient_Nat implements natural numbers by integers, which in general will
  3974     result in higher efficency; pattern matching with 0/Suc is eliminated;
  3975     includes Code_Integer.
  3976   - Code_Index provides an additional datatype index which is mapped to
  3977     target-language built-in integers.
  3978   - Code_Message provides an additional datatype message_string which is isomorphic to
  3979     strings; messages are mapped to target-language strings.
  3980 
  3981 * New package for inductive predicates
  3982 
  3983   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  3984 
  3985     inductive
  3986       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3987       for z_1 :: U_1 and ... and z_n :: U_m
  3988     where
  3989       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3990     | ...
  3991 
  3992   with full support for type-inference, rather than
  3993 
  3994     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3995 
  3996     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3997     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3998 
  3999     inductive "s z_1 ... z_m"
  4000     intros
  4001       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4002       ...
  4003 
  4004   For backward compatibility, there is a wrapper allowing inductive
  4005   sets to be defined with the new package via
  4006 
  4007     inductive_set
  4008       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4009       for z_1 :: U_1 and ... and z_n :: U_m
  4010     where
  4011       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4012     | ...
  4013 
  4014   or
  4015 
  4016     inductive_set
  4017       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4018       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4019       for z_1 :: U_1 and ... and z_n :: U_m
  4020     where
  4021       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4022     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4023     | ...
  4024 
  4025   if the additional syntax "p ..." is required.
  4026 
  4027   Numerous examples can be found in the subdirectories src/HOL/Auth,
  4028   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  4029 
  4030   INCOMPATIBILITIES:
  4031 
  4032   - Since declaration and definition of inductive sets or predicates
  4033     is no longer separated, abbreviations involving the newly
  4034     introduced sets or predicates must be specified together with the
  4035     introduction rules after the 'where' keyword (see above), rather
  4036     than before the actual inductive definition.
  4037 
  4038   - The variables in induction and elimination rules are now
  4039     quantified in the order of their occurrence in the introduction
  4040     rules, rather than in alphabetical order. Since this may break
  4041     some proofs, these proofs either have to be repaired, e.g. by
  4042     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  4043     statements of the form
  4044 
  4045       case (rule_i a_i_1 ... a_i_{k_i})
  4046 
  4047     or the old order of quantification has to be restored by explicitly adding
  4048     meta-level quantifiers in the introduction rules, i.e.
  4049 
  4050       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  4051 
  4052   - The format of the elimination rules is now
  4053 
  4054       p z_1 ... z_m x_1 ... x_n ==>
  4055         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4056         ==> ... ==> P
  4057 
  4058     for predicates and
  4059 
  4060       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4061         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4062         ==> ... ==> P
  4063 
  4064     for sets rather than
  4065 
  4066       x : s z_1 ... z_m ==>
  4067         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4068         ==> ... ==> P
  4069 
  4070     This may require terms in goals to be expanded to n-tuples
  4071     (e.g. using case_tac or simplification with the split_paired_all
  4072     rule) before the above elimination rule is applicable.
  4073 
  4074   - The elimination or case analysis rules for (mutually) inductive
  4075     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4076     list of rules "p_1_..._p_k.elims" is no longer available.
  4077 
  4078 * New package "function"/"fun" for general recursive functions,
  4079 supporting mutual and nested recursion, definitions in local contexts,
  4080 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4081 for small examples, and the separate tutorial on the function
  4082 package. The old recdef "package" is still available as before, but
  4083 users are encouraged to use the new package.
  4084 
  4085 * Method "lexicographic_order" automatically synthesizes termination
  4086 relations as lexicographic combinations of size measures. 
  4087 
  4088 * Case-expressions allow arbitrary constructor-patterns (including
  4089 "_") and take their order into account, like in functional
  4090 programming.  Internally, this is translated into nested
  4091 case-expressions; missing cases are added and mapped to the predefined
  4092 constant "undefined". In complicated cases printing may no longer show
  4093 the original input but the internal form. Lambda-abstractions allow
  4094 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4095 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4096 variable.
  4097 
  4098 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4099 is an abbreviation for "of_nat :: nat => int". The simplification
  4100 rules for "of_nat" have been changed to work like "int" did
  4101 previously.  Potential INCOMPATIBILITY:
  4102   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4103   - of_nat_diff and of_nat_mult are no longer default simp rules
  4104 
  4105 * Method "algebra" solves polynomial equations over (semi)rings using
  4106 Groebner bases. The (semi)ring structure is defined by locales and the
  4107 tool setup depends on that generic context. Installing the method for
  4108 a specific type involves instantiating the locale and possibly adding
  4109 declarations for computation on the coefficients.  The method is
  4110 already instantiated for natural numbers and for the axiomatic class
  4111 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4112 CALCULEMUS 2007 for the general principles underlying this
  4113 architecture of context-aware proof-tools.
  4114 
  4115 * Method "ferrack" implements quantifier elimination over
  4116 special-purpose dense linear orders using locales (analogous to
  4117 "algebra"). The method is already installed for class
  4118 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4119 rat, etc.
  4120 
  4121 * Former constant "List.op @" now named "List.append".  Use ML
  4122 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4123 circumvent possible incompatibilities when working on ML level.
  4124 
  4125 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4126 
  4127 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4128 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4129 
  4130 * New syntax for Haskell-like list comprehension (input only), eg.
  4131 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4132 
  4133 * The special syntax for function "filter" has changed from [x :
  4134 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4135 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4136 
  4137 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4138 defined on nat only, as an abbreviation for [a..<Suc b]
  4139 INCOMPATIBILITY.
  4140 
  4141 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4142 
  4143 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4144 
  4145 * New lemma collection field_simps (an extension of ring_simps) for
  4146 manipulating (in)equations involving division. Multiplies with all
  4147 denominators that can be proved to be non-zero (in equations) or
  4148 positive/negative (in inequations).
  4149 
  4150 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4151 have been improved and renamed to ring_simps, group_simps and
  4152 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4153 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4154 
  4155 * Theory Library/Commutative_Ring: switched from recdef to function
  4156 package; constants add, mul, pow now curried.  Infix syntax for
  4157 algebraic operations.
  4158 
  4159 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4160 INCOMPATIBILITY.
  4161 
  4162 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4163 INCOMPATIBILITY.
  4164 
  4165 * HOL/records: generalised field-update to take a function on the
  4166 field rather than the new value: r(|A := x|) is translated to A_update
  4167 (K x) r The K-combinator that is internally used is called K_record.
  4168 INCOMPATIBILITY: Usage of the plain update functions has to be
  4169 adapted.
  4170  
  4171 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4172 * x = 0, which are required for a semiring.  Richer structures do not
  4173 inherit from semiring_0 anymore, because this property is a theorem
  4174 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4175 there is more to prove, but this is mostly trivial.
  4176 
  4177 * Class "recpower" is generalized to arbitrary monoids, not just
  4178 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4179 commutativity or semiring properties additionally.
  4180 
  4181 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4182 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4183 better use 'abbreviation'.
  4184 
  4185 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4186 
  4187 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4188 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4189 significant changes for setting up numeral syntax for types:
  4190   - New constants Numeral.pred and Numeral.succ instead
  4191       of former Numeral.bin_pred and Numeral.bin_succ.
  4192   - Use integer operations instead of bin_add, bin_mult and so on.
  4193   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4194   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4195 
  4196 See src/HOL/Integ/IntArith.thy for an example setup.
  4197 
  4198 * Command 'normal_form' computes the normal form of a term that may
  4199 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4200 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4201 heavy-duty computations because the functions are compiled to ML
  4202 first.  Correspondingly, a method "normalization" is provided.  See
  4203 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4204 
  4205 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4206 25 like -->); output depends on the "iff" print_mode, the default is
  4207 "A = B" (with priority 50).
  4208 
  4209 * Relations less (<) and less_eq (<=) are also available on type bool.
  4210 Modified syntax to disallow nesting without explicit parentheses,
  4211 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4212 INCOMPATIBILITY.
  4213 
  4214 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4215 
  4216 * Relation composition operator "op O" now has precedence 75 and binds
  4217 stronger than union and intersection. INCOMPATIBILITY.
  4218 
  4219 * The old set interval syntax "{m..n(}" (and relatives) has been
  4220 removed.  Use "{m..<n}" (and relatives) instead.
  4221 
  4222 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4223 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4224 ``declare [[simproc del: neq]]''.
  4225 
  4226 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4227 True/False.
  4228 
  4229 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4230 
  4231 * Theorem setsum_mult renamed to setsum_right_distrib.
  4232 
  4233 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4234 ``rule'' method.
  4235 
  4236 * Reimplemented methods "sat" and "satx", with several improvements:
  4237 goals no longer need to be stated as "<prems> ==> False", equivalences
  4238 (i.e. "=" on type bool) are handled, variable names of the form
  4239 "lit_<n>" are no longer reserved, significant speedup.
  4240 
  4241 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4242 zChaff is still supported as well.
  4243 
  4244 * 'inductive' and 'datatype': provide projections of mutual rules,
  4245 bundled as foo_bar.inducts;
  4246 
  4247 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4248 Library.
  4249 
  4250 * Library: moved theory Accessible_Part to main HOL.
  4251 
  4252 * Library: added theory Coinductive_List of potentially infinite lists
  4253 as greatest fixed-point.
  4254 
  4255 * Library: added theory AssocList which implements (finite) maps as
  4256 association lists.
  4257 
  4258 * Method "evaluation" solves goals (i.e. a boolean expression)
  4259 efficiently by compiling it to ML.  The goal is "proved" (via an
  4260 oracle) if it evaluates to True.
  4261 
  4262 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4263 also when invoked by the simplifier.  This results in the Simplifier
  4264 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4265 Configuration option fast_arith_split_limit=0 recovers the old
  4266 behavior.
  4267 
  4268 * Support for hex (0x20) and binary (0b1001) numerals.
  4269 
  4270 * New method: reify eqs (t), where eqs are equations for an
  4271 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4272 parameter, computes a term s::'b and a list xs::'a list and proves the
  4273 theorem I xs s = t. This is also known as reification or quoting. The
  4274 resulting theorem is applied to the subgoal to substitute t with I xs
  4275 s.  If t is omitted, the subgoal itself is reified.
  4276 
  4277 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4278 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4279 where f is supposed to be a computable function (in the sense of code
  4280 generattion). The method uses reify to compute s and xs as above then
  4281 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4282 r and finally gets the theorem t = r, which is again applied to the
  4283 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4284 
  4285 * Reflection: Automatic reification now handels binding, an example is
  4286 available in src/HOL/ex/ReflectionEx.thy
  4287 
  4288 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4289 command 'statespace' that is similar to 'record', but introduces an
  4290 abstract specification based on the locale infrastructure instead of
  4291 HOL types.  This leads to extra flexibility in composing state spaces,
  4292 in particular multiple inheritance and renaming of components.
  4293 
  4294 
  4295 *** HOL-Complex ***
  4296 
  4297 * Hyperreal: Functions root and sqrt are now defined on negative real
  4298 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4299 Nonnegativity side conditions have been removed from many lemmas, so
  4300 that more subgoals may now be solved by simplification; potential
  4301 INCOMPATIBILITY.
  4302 
  4303 * Real: new type classes formalize real normed vector spaces and
  4304 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4305 and norm :: 'a => real.
  4306 
  4307 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4308 reals into other types. The overloaded constant Reals :: 'a set is now
  4309 defined as range of_real; potential INCOMPATIBILITY.
  4310 
  4311 * Real: proper support for ML code generation, including 'quickcheck'.
  4312 Reals are implemented as arbitrary precision rationals.
  4313 
  4314 * Hyperreal: Several constants that previously worked only for the
  4315 reals have been generalized, so they now work over arbitrary vector
  4316 spaces. Type annotations may need to be added in some cases; potential
  4317 INCOMPATIBILITY.
  4318 
  4319   Infinitesimal  :: ('a::real_normed_vector) star set
  4320   HFinite        :: ('a::real_normed_vector) star set
  4321   HInfinite      :: ('a::real_normed_vector) star set
  4322   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4323   monad          :: ('a::real_normed_vector) star => 'a star set
  4324   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4325   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4326   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4327   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4328   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4329   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4330   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4331   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4332   sgn            :: 'a::real_normed_vector => 'a
  4333   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4334 
  4335 * Complex: Some complex-specific constants are now abbreviations for
  4336 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4337 hnorm.  Other constants have been entirely removed in favor of the
  4338 polymorphic versions (INCOMPATIBILITY):
  4339 
  4340   approx        <-- capprox
  4341   HFinite       <-- CFinite
  4342   HInfinite     <-- CInfinite
  4343   Infinitesimal <-- CInfinitesimal
  4344   monad         <-- cmonad
  4345   galaxy        <-- cgalaxy
  4346   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4347   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4348   (ns)deriv     <-- (ns)cderiv
  4349 
  4350 
  4351 *** HOL-Algebra ***
  4352 
  4353 * Formalisation of ideals and the quotient construction over rings.
  4354 
  4355 * Order and lattice theory no longer based on records.
  4356 INCOMPATIBILITY.
  4357 
  4358 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4359 greatest_closed.  INCOMPATIBILITY.
  4360 
  4361 * Method algebra is now set up via an attribute.  For examples see
  4362 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4363 of algebraic structures.
  4364 
  4365 * Renamed theory CRing to Ring.
  4366 
  4367 
  4368 *** HOL-Nominal ***
  4369 
  4370 * Substantial, yet incomplete support for nominal datatypes (binding
  4371 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4372 src/HOL/Nominal/Examples.  Prospective users should consult
  4373 http://isabelle.in.tum.de/nominal/
  4374 
  4375 
  4376 *** ML ***
  4377 
  4378 * ML basics: just one true type int, which coincides with IntInf.int
  4379 (even on SML/NJ).
  4380 
  4381 * ML within Isar: antiquotations allow to embed statically-checked
  4382 formal entities in the source, referring to the context available at
  4383 compile-time.  For example:
  4384 
  4385 ML {* @{sort "{zero,one}"} *}
  4386 ML {* @{typ "'a => 'b"} *}
  4387 ML {* @{term "%x. x"} *}
  4388 ML {* @{prop "x == y"} *}
  4389 ML {* @{ctyp "'a => 'b"} *}
  4390 ML {* @{cterm "%x. x"} *}
  4391 ML {* @{cprop "x == y"} *}
  4392 ML {* @{thm asm_rl} *}
  4393 ML {* @{thms asm_rl} *}
  4394 ML {* @{type_name c} *}
  4395 ML {* @{type_syntax c} *}
  4396 ML {* @{const_name c} *}
  4397 ML {* @{const_syntax c} *}
  4398 ML {* @{context} *}
  4399 ML {* @{theory} *}
  4400 ML {* @{theory Pure} *}
  4401 ML {* @{theory_ref} *}
  4402 ML {* @{theory_ref Pure} *}
  4403 ML {* @{simpset} *}
  4404 ML {* @{claset} *}
  4405 ML {* @{clasimpset} *}
  4406 
  4407 The same works for sources being ``used'' within an Isar context.
  4408 
  4409 * ML in Isar: improved error reporting; extra verbosity with
  4410 ML_Context.trace enabled.
  4411 
  4412 * Pure/General/table.ML: the join operations now works via exceptions
  4413 DUP/SAME instead of type option. This is simpler in simple cases, and
  4414 admits slightly more efficient complex applications.
  4415 
  4416 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4417 use Context.generic instead of just theory.
  4418 
  4419 * Pure: datatype Context.generic joins theory/Proof.context and
  4420 provides some facilities for code that works in either kind of
  4421 context, notably GenericDataFun for uniform theory and proof data.
  4422 
  4423 * Pure: simplified internal attribute type, which is now always
  4424 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4425 local (Proof.context) attributes have been discontinued, while
  4426 minimizing code duplication. Thm.rule_attribute and
  4427 Thm.declaration_attribute build canonical attributes; see also structure
  4428 Context for further operations on Context.generic, notably
  4429 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4430 declarations and definitions.
  4431 
  4432 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4433 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4434 init only required for impure data. INCOMPATIBILITY: empty really need
  4435 to be empty (no dependencies on theory content!)
  4436 
  4437 * Pure/kernel: consts certification ignores sort constraints given in
  4438 signature declarations. (This information is not relevant to the
  4439 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4440 potential INCOMPATIBILITY.
  4441 
  4442 * Pure: axiomatic type classes are now purely definitional, with
  4443 explicit proofs of class axioms and super class relations performed
  4444 internally. See Pure/axclass.ML for the main internal interfaces --
  4445 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4446 AxClass.axiomatize_class/classrel/arity supersede
  4447 Sign.add_classes/classrel/arities.
  4448 
  4449 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4450 global/local versions on theory vs. Proof.context have been
  4451 discontinued; Attrib.syntax and Method.syntax have been adapted
  4452 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4453 attributes, methods, etc.
  4454 
  4455 * Pure: several functions of signature "... -> theory -> theory * ..."
  4456 have been reoriented to "... -> theory -> ... * theory" in order to
  4457 allow natural usage in combination with the ||>, ||>>, |-> and
  4458 fold_map combinators.
  4459 
  4460 * Pure: official theorem names (closed derivations) and additional
  4461 comments (tags) are now strictly separate.  Name hints -- which are
  4462 maintained as tags -- may be attached any time without affecting the
  4463 derivation.
  4464 
  4465 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4466 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4467 achieve the old behaviour.
  4468 
  4469 * Pure: the "Goal" constant is now called "prop", supporting a
  4470 slightly more general idea of ``protecting'' meta-level rule
  4471 statements.
  4472 
  4473 * Pure: Logic.(un)varify only works in a global context, which is now
  4474 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4475 Logic.legacy_(un)varify as temporary workaround.
  4476 
  4477 * Pure: structure Name provides scalable operations for generating
  4478 internal variable names, notably Name.variants etc.  This replaces
  4479 some popular functions from term.ML:
  4480 
  4481   Term.variant		->  Name.variant
  4482   Term.variantlist	->  Name.variant_list
  4483   Term.invent_names	->  Name.invent_list
  4484 
  4485 Note that low-level renaming rarely occurs in new code -- operations
  4486 from structure Variable are used instead (see below).
  4487 
  4488 * Pure: structure Variable provides fundamental operations for proper
  4489 treatment of fixed/schematic variables in a context.  For example,
  4490 Variable.import introduces fixes for schematics of given facts and
  4491 Variable.export reverses the effect (up to renaming) -- this replaces
  4492 various freeze_thaw operations.
  4493 
  4494 * Pure: structure Goal provides simple interfaces for
  4495 init/conclude/finish and tactical prove operations (replacing former
  4496 Tactic.prove).  Goal.prove is the canonical way to prove results
  4497 within a given context; Goal.prove_global is a degraded version for
  4498 theory level goals, including a global Drule.standard.  Note that
  4499 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4500 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4501 in a locale context).
  4502 
  4503 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4504 and type checking (Syntax.check_term etc.), with common combinations
  4505 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4506 which are considered legacy and await removal.
  4507 
  4508 * Pure/Syntax: generic interfaces for type unchecking
  4509 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4510 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4511 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4512 available for convenience, but refer to the very same operations using
  4513 a mere theory instead of a full context.
  4514 
  4515 * Isar: simplified treatment of user-level errors, using exception
  4516 ERROR of string uniformly.  Function error now merely raises ERROR,
  4517 without any side effect on output channels.  The Isar toplevel takes
  4518 care of proper display of ERROR exceptions.  ML code may use plain
  4519 handle/can/try; cat_error may be used to concatenate errors like this:
  4520 
  4521   ... handle ERROR msg => cat_error msg "..."
  4522 
  4523 Toplevel ML code (run directly or through the Isar toplevel) may be
  4524 embedded into the Isar toplevel with exception display/debug like
  4525 this:
  4526 
  4527   Isar.toplevel (fn () => ...)
  4528 
  4529 INCOMPATIBILITY, removed special transform_error facilities, removed
  4530 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4531 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4532 -- use plain ERROR instead.
  4533 
  4534 * Isar: theory setup now has type (theory -> theory), instead of a
  4535 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4536 
  4537 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4538 ProofContext.debug/verbose flags.
  4539 
  4540 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4541 theory before entering a proof state.  Transactions now always see a
  4542 quasi-functional intermediate checkpoint, both in interactive and
  4543 batch mode.
  4544 
  4545 * Isar: simplified interfaces for outer syntax.  Renamed
  4546 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4547 OuterSyntax.add_parsers -- this functionality is now included in
  4548 OuterSyntax.command etc.  INCOMPATIBILITY.
  4549 
  4550 * Simplifier: the simpset of a running simplification process now
  4551 contains a proof context (cf. Simplifier.the_context), which is the
  4552 very context that the initial simpset has been retrieved from (by
  4553 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4554 (solver, looper etc.) may depend on arbitrary proof data.
  4555 
  4556 * Simplifier.inherit_context inherits the proof context (plus the
  4557 local bounds) of the current simplification process; any simproc
  4558 etc. that calls the Simplifier recursively should do this!  Removed
  4559 former Simplifier.inherit_bounds, which is already included here --
  4560 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4561 specify an explicit context using Simplifier.context/theory_context.
  4562 
  4563 * Simplifier/Classical Reasoner: more abstract interfaces
  4564 change_simpset/claset for modifying the simpset/claset reference of a
  4565 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4566 INCOMPATIBILITY.
  4567 
  4568 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4569 "Trueprop" etc.
  4570 
  4571 
  4572 *** System ***
  4573 
  4574 * settings: the default heap location within ISABELLE_HOME_USER now
  4575 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4576 Isabelle installations.
  4577 
  4578 * isabelle-process: option -S (secure mode) disables some critical
  4579 operations, notably runtime compilation and evaluation of ML source
  4580 code.
  4581 
  4582 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4583 
  4584 * Support for parallel execution, using native multicore support of
  4585 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4586 independent theories, according to the given theory header
  4587 specifications. The maximum number of worker threads is specified via
  4588 usedir option -M or the "max-threads" setting in Proof General. A
  4589 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4590 to 6 on a 8-core machine.  User-code needs to observe certain
  4591 guidelines for thread-safe programming, see appendix A in the Isar
  4592 Implementation manual.
  4593 
  4594 
  4595 
  4596 New in Isabelle2005 (October 2005)
  4597 ----------------------------------
  4598 
  4599 *** General ***
  4600 
  4601 * Theory headers: the new header syntax for Isar theories is
  4602 
  4603   theory <name>
  4604   imports <theory1> ... <theoryN>
  4605   uses <file1> ... <fileM>
  4606   begin
  4607 
  4608 where the 'uses' part is optional.  The previous syntax
  4609 
  4610   theory <name> = <theory1> + ... + <theoryN>:
  4611 
  4612 will disappear in the next release.  Use isatool fixheaders to convert
  4613 existing theory files.  Note that there is no change in ancient
  4614 non-Isar theories now, but these will disappear soon.
  4615 
  4616 * Theory loader: parent theories can now also be referred to via
  4617 relative and absolute paths.
  4618 
  4619 * Command 'find_theorems' searches for a list of criteria instead of a
  4620 list of constants. Known criteria are: intro, elim, dest, name:string,
  4621 simp:term, and any term. Criteria can be preceded by '-' to select
  4622 theorems that do not match. Intro, elim, dest select theorems that
  4623 match the current goal, name:s selects theorems whose fully qualified
  4624 name contain s, and simp:term selects all simplification rules whose
  4625 lhs match term.  Any other term is interpreted as pattern and selects
  4626 all theorems matching the pattern. Available in ProofGeneral under
  4627 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4628 
  4629   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4630 
  4631 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4632 matching the current goal as introduction rule and not having "HOL."
  4633 in their name (i.e. not being defined in theory HOL).
  4634 
  4635 * Command 'thms_containing' has been discontinued in favour of
  4636 'find_theorems'; INCOMPATIBILITY.
  4637 
  4638 * Communication with Proof General is now 8bit clean, which means that
  4639 Unicode text in UTF-8 encoding may be used within theory texts (both
  4640 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4641 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4642 
  4643   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4644   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4645 
  4646 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4647 Classical Reasoner.  Typical big applications run around 2 times
  4648 faster.
  4649 
  4650 
  4651 *** Document preparation ***
  4652 
  4653 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4654 of raw sources.  Only those symbols that do not require additional
  4655 LaTeX packages (depending on comments in isabellesym.sty) are
  4656 displayed properly, everything else is left verbatim.  isatool display
  4657 and isatool print are used as front ends (these are subject to the
  4658 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4659 
  4660 * Command tags control specific markup of certain regions of text,
  4661 notably folding and hiding.  Predefined tags include "theory" (for
  4662 theory begin and end), "proof" for proof commands, and "ML" for
  4663 commands involving ML code; the additional tags "visible" and
  4664 "invisible" are unused by default.  Users may give explicit tag
  4665 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4666 interpretation of tags is determined by the LaTeX job during document
  4667 preparation: see option -V of isatool usedir, or options -n and -t of
  4668 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4669 \isadroptag.
  4670 
  4671 Several document versions may be produced at the same time via isatool
  4672 usedir (the generated index.html will link all of them).  Typical
  4673 specifications include ''-V document=theory,proof,ML'' to present
  4674 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4675 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4676 these parts without any formal replacement text.  The Isabelle site
  4677 default settings produce ''document'' and ''outline'' versions as
  4678 specified above.
  4679 
  4680 * Several new antiquotations:
  4681 
  4682   @{term_type term} prints a term with its type annotated;
  4683 
  4684   @{typeof term} prints the type of a term;
  4685 
  4686   @{const const} is the same as @{term const}, but checks that the
  4687   argument is a known logical constant;
  4688 
  4689   @{term_style style term} and @{thm_style style thm} print a term or
  4690   theorem applying a "style" to it
  4691 
  4692   @{ML text}
  4693 
  4694 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4695 definitions, equations, inequations etc., 'concl' printing only the
  4696 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4697 to print the specified premise.  TermStyle.add_style provides an ML
  4698 interface for introducing further styles.  See also the "LaTeX Sugar"
  4699 document practical applications.  The ML antiquotation prints
  4700 type-checked ML expressions verbatim.
  4701 
  4702 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4703 and 'text' support optional locale specification '(in loc)', which
  4704 specifies the default context for interpreting antiquotations.  For
  4705 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4706 
  4707 * Option 'locale=NAME' of antiquotations specifies an alternative
  4708 context interpreting the subsequent argument.  For example: @{thm
  4709 [locale=lattice] inf_assoc}.
  4710 
  4711 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4712 a proof context.
  4713 
  4714 * Proper output of antiquotations for theory commands involving a
  4715 proof context (such as 'locale' or 'theorem (in loc) ...').
  4716 
  4717 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4718 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4719 
  4720 * isatool usedir: new option -C (default true) controls whether option
  4721 -D should include a copy of the original document directory; -C false
  4722 prevents unwanted effects such as copying of administrative CVS data.
  4723 
  4724 
  4725 *** Pure ***
  4726 
  4727 * Considerably improved version of 'constdefs' command.  Now performs
  4728 automatic type-inference of declared constants; additional support for
  4729 local structure declarations (cf. locales and HOL records), see also
  4730 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4731 sequential dependencies of definitions within a single 'constdefs'
  4732 section; moreover, the declared name needs to be an identifier.  If
  4733 all fails, consider to fall back on 'consts' and 'defs' separately.
  4734 
  4735 * Improved indexed syntax and implicit structures.  First of all,
  4736 indexed syntax provides a notational device for subscripted
  4737 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4738 expressions.  Secondly, in a local context with structure
  4739 declarations, number indexes \<^sub>n or the empty index (default
  4740 number 1) refer to a certain fixed variable implicitly; option
  4741 show_structs controls printing of implicit structures.  Typical
  4742 applications of these concepts involve record types and locales.
  4743 
  4744 * New command 'no_syntax' removes grammar declarations (and
  4745 translations) resulting from the given syntax specification, which is
  4746 interpreted in the same manner as for the 'syntax' command.
  4747 
  4748 * 'Advanced' translation functions (parse_translation etc.) may depend
  4749 on the signature of the theory context being presently used for
  4750 parsing/printing, see also isar-ref manual.
  4751 
  4752 * Improved 'oracle' command provides a type-safe interface to turn an
  4753 ML expression of type theory -> T -> term into a primitive rule of
  4754 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4755 is already included here); see also FOL/ex/IffExample.thy;
  4756 INCOMPATIBILITY.
  4757 
  4758 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4759 before); "cI" is no longer bound, use "c.intro" instead.
  4760 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4761 axclasses vs. locales.
  4762 
  4763 * Improved internal renaming of symbolic identifiers -- attach primes
  4764 instead of base 26 numbers.
  4765 
  4766 * New flag show_question_marks controls printing of leading question
  4767 marks in schematic variable names.
  4768 
  4769 * In schematic variable names, *any* symbol following \<^isub> or
  4770 \<^isup> is now treated as part of the base name.  For example, the
  4771 following works without printing of awkward ".0" indexes:
  4772 
  4773   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4774     by simp
  4775 
  4776 * Inner syntax includes (*(*nested*) comments*).
  4777 
  4778 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4779 annotations as "(00...)".
  4780 
  4781 * Clear separation of logical types and nonterminals, where the latter
  4782 may only occur in 'syntax' specifications or type abbreviations.
  4783 Before that distinction was only partially implemented via type class
  4784 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4785 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4786 exotic syntax specifications may require further adaption
  4787 (e.g. Cube/Cube.thy).
  4788 
  4789 * Removed obsolete type class "logic", use the top sort {} instead.
  4790 Note that non-logical types should be declared as 'nonterminals'
  4791 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4792 specifications.
  4793 
  4794 * Attributes 'induct' and 'cases': type or set names may now be
  4795 locally fixed variables as well.
  4796 
  4797 * Simplifier: can now control the depth to which conditional rewriting
  4798 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4799 Limit.
  4800 
  4801 * Simplifier: simplification procedures may now take the current
  4802 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4803 interface), which is very useful for calling the Simplifier
  4804 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4805 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4806 low-level mk_simproc no longer applies Logic.varify internally, to
  4807 allow for use in a context of fixed variables.
  4808 
  4809 * thin_tac now works even if the assumption being deleted contains !!
  4810 or ==>.  More generally, erule now works even if the major premise of
  4811 the elimination rule contains !! or ==>.
  4812 
  4813 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4814 
  4815 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4816 from Pure, which contains all common declarations already.  Both
  4817 theories are defined via plain Isabelle/Isar .thy files.
  4818 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4819 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4820 use isatool fixcpure to adapt your theory and ML sources.
  4821 
  4822 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4823 selections of theorems in named facts via index ranges.
  4824 
  4825 * 'print_theorems': in theory mode, really print the difference
  4826 wrt. the last state (works for interactive theory development only),
  4827 in proof mode print all local facts (cf. 'print_facts');
  4828 
  4829 * 'hide': option '(open)' hides only base names.
  4830 
  4831 * More efficient treatment of intermediate checkpoints in interactive
  4832 theory development.
  4833 
  4834 * Code generator is now invoked via code_module (incremental code
  4835 generation) and code_library (modular code generation, ML structures
  4836 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4837 must be quoted when used as identifiers.
  4838 
  4839 * New 'value' command for reading, evaluating and printing terms using
  4840 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4841 quoted when used as identifier.
  4842 
  4843 
  4844 *** Locales ***
  4845 
  4846 * New commands for the interpretation of locale expressions in
  4847 theories (1), locales (2) and proof contexts (3).  These generate
  4848 proof obligations from the expression specification.  After the
  4849 obligations have been discharged, theorems of the expression are added
  4850 to the theory, target locale or proof context.  The synopsis of the
  4851 commands is a follows:
  4852 
  4853   (1) interpretation expr inst
  4854   (2) interpretation target < expr
  4855   (3) interpret expr inst
  4856 
  4857 Interpretation in theories and proof contexts require a parameter
  4858 instantiation of terms from the current context.  This is applied to
  4859 specifications and theorems of the interpreted expression.
  4860 Interpretation in locales only permits parameter renaming through the
  4861 locale expression.  Interpretation is smart in that interpretations
  4862 that are active already do not occur in proof obligations, neither are
  4863 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4864 inspect active interpretations of a particular locale.  For details,
  4865 see the Isar Reference manual.  Examples can be found in
  4866 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4867 
  4868 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4869 'interpret' instead.
  4870 
  4871 * New context element 'constrains' for adding type constraints to
  4872 parameters.
  4873 
  4874 * Context expressions: renaming of parameters with syntax
  4875 redeclaration.
  4876 
  4877 * Locale declaration: 'includes' disallowed.
  4878 
  4879 * Proper static binding of attribute syntax -- i.e. types / terms /
  4880 facts mentioned as arguments are always those of the locale definition
  4881 context, independently of the context of later invocations.  Moreover,
  4882 locale operations (renaming and type / term instantiation) are applied
  4883 to attribute arguments as expected.
  4884 
  4885 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4886 actual attributes; rare situations may require Attrib.attribute to
  4887 embed those attributes into Attrib.src that lack concrete syntax.
  4888 Attribute implementations need to cooperate properly with the static
  4889 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4890 Attrib.XXX_thm etc. already do the right thing without further
  4891 intervention.  Only unusual applications -- such as "where" or "of"
  4892 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4893 on the context and the facts involved -- may have to assign parsed
  4894 values to argument tokens explicitly.
  4895 
  4896 * Changed parameter management in theorem generation for long goal
  4897 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4898 theorem statement in rare situations.
  4899 
  4900 * Locale inspection command 'print_locale' omits notes elements.  Use
  4901 'print_locale!' to have them included in the output.
  4902 
  4903 
  4904 *** Provers ***
  4905 
  4906 * Provers/hypsubst.ML: improved version of the subst method, for
  4907 single-step rewriting: it now works in bound variable contexts. New is
  4908 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4909 rewrite a different subterm than the original subst method, which is
  4910 still available as 'simplesubst'.
  4911 
  4912 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4913 and quasi orders.
  4914 
  4915 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4916 reflexive-transitive closure of relations.
  4917 
  4918 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4919 limit (previously hard-coded with a value of 20) user-definable.
  4920 
  4921 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4922 is peformed already.  Object-logics merely need to finish their
  4923 initial simpset configuration as before.  INCOMPATIBILITY.
  4924 
  4925 
  4926 *** HOL ***
  4927 
  4928 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4929 
  4930   syntax (epsilon)
  4931     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4932 
  4933 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4934 and x-symbol; use option '-m epsilon' to get it actually printed.
  4935 Moreover, the mathematically important symbolic identifier \<epsilon>
  4936 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4937 
  4938 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  4939 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  4940 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  4941 support corresponding Isar calculations.
  4942 
  4943 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  4944 instead of ":".
  4945 
  4946 * theory SetInterval: changed the syntax for open intervals:
  4947 
  4948   Old       New
  4949   {..n(}    {..<n}
  4950   {)n..}    {n<..}
  4951   {m..n(}   {m..<n}
  4952   {)m..n}   {m<..n}
  4953   {)m..n(}  {m<..<n}
  4954 
  4955 The old syntax is still supported but will disappear in the next
  4956 release.  For conversion use the following Emacs search and replace
  4957 patterns (these are not perfect but work quite well):
  4958 
  4959   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  4960   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  4961 
  4962 * Theory Commutative_Ring (in Library): method comm_ring for proving
  4963 equalities in commutative rings; method 'algebra' provides a generic
  4964 interface.
  4965 
  4966 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  4967 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  4968 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  4969 be a tuple pattern.
  4970 
  4971 Some new syntax forms are available:
  4972 
  4973   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  4974   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  4975   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  4976   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  4977 
  4978 The latter form "\<Sum>x < k. e" used to be based on a separate
  4979 function "Summation", which has been discontinued.
  4980 
  4981 * theory Finite_Set: in structured induction proofs, the insert case
  4982 is now 'case (insert x F)' instead of the old counterintuitive 'case
  4983 (insert F x)'.
  4984 
  4985 * The 'refute' command has been extended to support a much larger
  4986 fragment of HOL, including axiomatic type classes, constdefs and
  4987 typedefs, inductive datatypes and recursion.
  4988 
  4989 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  4990 Requires zChaff with proof generation to be installed.  See
  4991 HOL/ex/SAT_Examples.thy for examples.
  4992 
  4993 * Datatype induction via method 'induct' now preserves the name of the
  4994 induction variable. For example, when proving P(xs::'a list) by
  4995 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  4996 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  4997 in unstructured proof scripts.
  4998 
  4999 * Reworked implementation of records.  Improved scalability for
  5000 records with many fields, avoiding performance problems for type
  5001 inference. Records are no longer composed of nested field types, but
  5002 of nested extension types. Therefore the record type only grows linear
  5003 in the number of extensions and not in the number of fields.  The
  5004 top-level (users) view on records is preserved.  Potential
  5005 INCOMPATIBILITY only in strange cases, where the theory depends on the
  5006 old record representation. The type generated for a record is called
  5007 <record_name>_ext_type.
  5008 
  5009 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  5010 proofs triggered by a record definition or a simproc (if
  5011 quick_and_dirty is enabled).  Definitions of large records can take
  5012 quite long.
  5013 
  5014 New simproc record_upd_simproc for simplification of multiple record
  5015 updates enabled by default.  Moreover, trivial updates are also
  5016 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  5017 occasionally, since simplification is more powerful by default.
  5018 
  5019 * typedef: proper support for polymorphic sets, which contain extra
  5020 type-variables in the term.
  5021 
  5022 * Simplifier: automatically reasons about transitivity chains
  5023 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  5024 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  5025 old proofs break occasionally as simplification may now solve more
  5026 goals than previously.
  5027 
  5028 * Simplifier: converts x <= y into x = y if assumption y <= x is
  5029 present.  Works for all partial orders (class "order"), in particular
  5030 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  5031 just like y <= x.
  5032 
  5033 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  5034 bound variable or a constant then the let is unfolded.  Otherwise
  5035 first a is simplified to b, and then f b is simplified to g. If
  5036 possible we abstract b from g arriving at "let x = b in h x",
  5037 otherwise we unfold the let and arrive at g.  The simproc can be
  5038 enabled/disabled by the reference use_let_simproc.  Potential
  5039 INCOMPATIBILITY since simplification is more powerful by default.
  5040 
  5041 * Classical reasoning: the meson method now accepts theorems as arguments.
  5042 
  5043 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  5044 jobs to provide advice on the provability of subgoals.
  5045 
  5046 * Theory OrderedGroup and Ring_and_Field: various additions and
  5047 improvements to faciliate calculations involving equalities and
  5048 inequalities.
  5049 
  5050 The following theorems have been eliminated or modified
  5051 (INCOMPATIBILITY):
  5052 
  5053   abs_eq             now named abs_of_nonneg
  5054   abs_of_ge_0        now named abs_of_nonneg
  5055   abs_minus_eq       now named abs_of_nonpos
  5056   imp_abs_id         now named abs_of_nonneg
  5057   imp_abs_neg_id     now named abs_of_nonpos
  5058   mult_pos           now named mult_pos_pos
  5059   mult_pos_le        now named mult_nonneg_nonneg
  5060   mult_pos_neg_le    now named mult_nonneg_nonpos
  5061   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5062   mult_neg           now named mult_neg_neg
  5063   mult_neg_le        now named mult_nonpos_nonpos
  5064 
  5065 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5066      
  5067      zero_le_square
  5068      not_square_less_zero 
  5069 
  5070   The following lemmas have been deleted from Real/RealPow:
  5071   
  5072      realpow_zero_zero
  5073      realpow_two
  5074      realpow_less
  5075      zero_le_power
  5076      realpow_two_le
  5077      abs_realpow_two
  5078      realpow_two_abs     
  5079 
  5080 * Theory Parity: added rules for simplifying exponents.
  5081 
  5082 * Theory List:
  5083 
  5084 The following theorems have been eliminated or modified
  5085 (INCOMPATIBILITY):
  5086 
  5087   list_all_Nil       now named list_all.simps(1)
  5088   list_all_Cons      now named list_all.simps(2)
  5089   list_all_conv      now named list_all_iff
  5090   set_mem_eq         now named mem_iff
  5091 
  5092 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5093 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5094 
  5095 
  5096 *** HOL-Complex ***
  5097 
  5098 * Theory RealDef: better support for embedding natural numbers and
  5099 integers in the reals.
  5100 
  5101 The following theorems have been eliminated or modified
  5102 (INCOMPATIBILITY):
  5103 
  5104   exp_ge_add_one_self  now requires no hypotheses
  5105   real_of_int_add      reversed direction of equality (use [symmetric])
  5106   real_of_int_minus    reversed direction of equality (use [symmetric])
  5107   real_of_int_diff     reversed direction of equality (use [symmetric])
  5108   real_of_int_mult     reversed direction of equality (use [symmetric])
  5109 
  5110 * Theory RComplete: expanded support for floor and ceiling functions.
  5111 
  5112 * Theory Ln is new, with properties of the natural logarithm
  5113 
  5114 * Hyperreal: There is a new type constructor "star" for making
  5115 nonstandard types.  The old type names are now type synonyms:
  5116 
  5117   hypreal = real star
  5118   hypnat = nat star
  5119   hcomplex = complex star
  5120 
  5121 * Hyperreal: Many groups of similarly-defined constants have been
  5122 replaced by polymorphic versions (INCOMPATIBILITY):
  5123 
  5124   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5125 
  5126   starset      <-- starsetNat, starsetC
  5127   *s*          <-- *sNat*, *sc*
  5128   starset_n    <-- starsetNat_n, starsetC_n
  5129   *sn*         <-- *sNatn*, *scn*
  5130   InternalSets <-- InternalNatSets, InternalCSets
  5131 
  5132   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5133   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5134   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5135   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5136   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5137 
  5138 * Hyperreal: Many type-specific theorems have been removed in favor of
  5139 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5140 
  5141   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5142   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5143   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5144   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5145   right_minus <-- hypreal_add_minus
  5146   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5147   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5148   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5149   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5150   mult_1_right <-- hcomplex_mult_one_right
  5151   mult_zero_left <-- hcomplex_mult_zero_left
  5152   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5153   right_distrib <-- hypnat_add_mult_distrib2
  5154   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5155   right_inverse <-- hypreal_mult_inverse
  5156   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5157   order_refl <-- {hypreal,hypnat}_le_refl
  5158   order_trans <-- {hypreal,hypnat}_le_trans
  5159   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5160   order_less_le <-- {hypreal,hypnat}_less_le
  5161   linorder_linear <-- {hypreal,hypnat}_le_linear
  5162   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5163   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5164   add_nonneg_nonneg <-- hypreal_le_add_order
  5165 
  5166 * Hyperreal: Separate theorems having to do with type-specific
  5167 versions of constants have been merged into theorems that apply to the
  5168 new polymorphic constants (INCOMPATIBILITY):
  5169 
  5170   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5171   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5172   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5173   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5174   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5175   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5176   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5177   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5178   STAR_diff <-- {STAR,STARC}_diff
  5179   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5180     STARC_hcomplex_of_complex}_image_subset
  5181   starset_n_Un <-- starset{Nat,C}_n_Un
  5182   starset_n_Int <-- starset{Nat,C}_n_Int
  5183   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5184   starset_n_diff <-- starset{Nat,C}_n_diff
  5185   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5186   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5187   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5188   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5189   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5190   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5191   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5192   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5193   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5194   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5195   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5196   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5197   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5198   starfun_diff <-- starfun{C,RC,CR}_diff
  5199   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5200   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5201   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5202   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5203   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5204   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5205   starfun_Id <-- starfunC_Id
  5206   starfun_approx <-- starfun{Nat,CR}_approx
  5207   starfun_capprox <-- starfun{C,RC}_capprox
  5208   starfun_abs <-- starfunNat_rabs
  5209   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5210   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5211   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5212   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5213   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5214   starfun_add_approx <-- starfunCR_add_approx
  5215   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5216   starfun_divide <-- starfun{C,CR,RC}_divide
  5217   starfun_n <-- starfun{Nat,C}_n
  5218   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5219   starfun_n_add <-- starfun{Nat,C}_n_add
  5220   starfun_n_add_minus <-- starfunNat_n_add_minus
  5221   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5222   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5223   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5224 
  5225   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5226   star_n_minus <-- {hypreal,hcomplex}_minus
  5227   star_n_diff <-- {hypreal,hcomplex}_diff
  5228   star_n_mult <-- {hypreal,hcomplex}_mult
  5229   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5230   star_n_le <-- {hypreal,hypnat}_le
  5231   star_n_less <-- {hypreal,hypnat}_less
  5232   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5233   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5234   star_n_abs <-- hypreal_hrabs
  5235   star_n_divide <-- hcomplex_divide
  5236 
  5237   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5238   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5239   star_of_diff <-- hypreal_of_real_diff
  5240   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5241   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5242   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5243   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5244   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5245   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5246   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5247   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5248   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5249   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5250   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5251   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5252   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5253   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5254   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5255   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5256   star_of_power <-- hypreal_of_real_power
  5257   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5258 
  5259 * Hyperreal: new method "transfer" that implements the transfer
  5260 principle of nonstandard analysis. With a subgoal that mentions
  5261 nonstandard types like "'a star", the command "apply transfer"
  5262 replaces it with an equivalent one that mentions only standard types.
  5263 To be successful, all free variables must have standard types; non-
  5264 standard variables must have explicit universal quantifiers.
  5265 
  5266 * Hyperreal: A theory of Taylor series.
  5267 
  5268 
  5269 *** HOLCF ***
  5270 
  5271 * Discontinued special version of 'constdefs' (which used to support
  5272 continuous functions) in favor of the general Pure one with full
  5273 type-inference.
  5274 
  5275 * New simplification procedure for solving continuity conditions; it
  5276 is much faster on terms with many nested lambda abstractions (cubic
  5277 instead of exponential time).
  5278 
  5279 * New syntax for domain package: selector names are now optional.
  5280 Parentheses should be omitted unless argument is lazy, for example:
  5281 
  5282   domain 'a stream = cons "'a" (lazy "'a stream")
  5283 
  5284 * New command 'fixrec' for defining recursive functions with pattern
  5285 matching; defining multiple functions with mutual recursion is also
  5286 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5287 sinr, or any data constructor defined by the domain package. The given
  5288 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5289 syntax and examples.
  5290 
  5291 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5292 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5293 but the proof obligation additionally includes an admissibility
  5294 requirement. The packages generate instances of class cpo or pcpo,
  5295 with continuity and strictness theorems for Rep and Abs.
  5296 
  5297 * HOLCF: Many theorems have been renamed according to a more standard naming
  5298 scheme (INCOMPATIBILITY):
  5299 
  5300   foo_inject:  "foo$x = foo$y ==> x = y"
  5301   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5302   foo_less:    "(foo$x << foo$y) = (x << y)"
  5303   foo_strict:  "foo$UU = UU"
  5304   foo_defined: "... ==> foo$x ~= UU"
  5305   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5306 
  5307 
  5308 *** ZF ***
  5309 
  5310 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5311 including the First Isomorphism Theorem (on quotienting by the kernel
  5312 of a homomorphism).
  5313 
  5314 * ZF/Simplifier: install second copy of type solver that actually
  5315 makes use of TC rules declared to Isar proof contexts (or locales);
  5316 the old version is still required for ML proof scripts.
  5317 
  5318 
  5319 *** Cube ***
  5320 
  5321 * Converted to Isar theory format; use locales instead of axiomatic
  5322 theories.
  5323 
  5324 
  5325 *** ML ***
  5326 
  5327 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5328 for ||>, ||>>, |>>,
  5329 
  5330 * Pure/library.ML no longer defines its own option datatype, but uses
  5331 that of the SML basis, which has constructors NONE and SOME instead of
  5332 None and Some, as well as exception Option.Option instead of OPTION.
  5333 The functions the, if_none, is_some, is_none have been adapted
  5334 accordingly, while Option.map replaces apsome.
  5335 
  5336 * Pure/library.ML: the exception LIST has been given up in favour of
  5337 the standard exceptions Empty and Subscript, as well as
  5338 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5339 superceded by the standard hd and tl functions etc.
  5340 
  5341 A number of basic list functions are no longer exported to the ML
  5342 toplevel, as they are variants of predefined functions.  The following
  5343 suggests how one can translate existing code:
  5344 
  5345     rev_append xs ys = List.revAppend (xs, ys)
  5346     nth_elem (i, xs) = List.nth (xs, i)
  5347     last_elem xs = List.last xs
  5348     flat xss = List.concat xss
  5349     seq fs = List.app fs
  5350     partition P xs = List.partition P xs
  5351     mapfilter f xs = List.mapPartial f xs
  5352 
  5353 * Pure/library.ML: several combinators for linear functional
  5354 transformations, notably reverse application and composition:
  5355 
  5356   x |> f                f #> g
  5357   (x, y) |-> f          f #-> g
  5358 
  5359 * Pure/library.ML: introduced/changed precedence of infix operators:
  5360 
  5361   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5362   infix 2 ?;
  5363   infix 3 o oo ooo oooo;
  5364   infix 4 ~~ upto downto;
  5365 
  5366 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5367 infix operators.
  5368 
  5369 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5370 fold_map support linear functional transformations and nesting.  For
  5371 example:
  5372 
  5373   fold f [x1, ..., xN] y =
  5374     y |> f x1 |> ... |> f xN
  5375 
  5376   (fold o fold) f [xs1, ..., xsN] y =
  5377     y |> fold f xs1 |> ... |> fold f xsN
  5378 
  5379   fold f [x1, ..., xN] =
  5380     f x1 #> ... #> f xN
  5381 
  5382   (fold o fold) f [xs1, ..., xsN] =
  5383     fold f xs1 #> ... #> fold f xsN
  5384 
  5385 * Pure/library.ML: the following selectors on type 'a option are
  5386 available:
  5387 
  5388   the:               'a option -> 'a  (*partial*)
  5389   these:             'a option -> 'a  where 'a = 'b list
  5390   the_default: 'a -> 'a option -> 'a
  5391   the_list:          'a option -> 'a list
  5392 
  5393 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5394 basic operations for association lists, following natural argument
  5395 order; moreover the explicit equality predicate passed here avoids
  5396 potentially expensive polymorphic runtime equality checks.
  5397 The old functions may be expressed as follows:
  5398 
  5399   assoc = uncurry (AList.lookup (op =))
  5400   assocs = these oo AList.lookup (op =)
  5401   overwrite = uncurry (AList.update (op =)) o swap
  5402 
  5403 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5404 
  5405   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5406   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5407 
  5408 replacing make_keylist and keyfilter (occassionally used)
  5409 Naive rewrites:
  5410 
  5411   make_keylist = AList.make
  5412   keyfilter = AList.find (op =)
  5413 
  5414 * eq_fst and eq_snd now take explicit equality parameter, thus
  5415   avoiding eqtypes. Naive rewrites:
  5416 
  5417     eq_fst = eq_fst (op =)
  5418     eq_snd = eq_snd (op =)
  5419 
  5420 * Removed deprecated apl and apr (rarely used).
  5421   Naive rewrites:
  5422 
  5423     apl (n, op) =>>= curry op n
  5424     apr (op, m) =>>= fn n => op (n, m)
  5425 
  5426 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5427 provides a reasonably efficient light-weight implementation of sets as
  5428 lists.
  5429 
  5430 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5431 few new operations; existing lookup and update are now curried to
  5432 follow natural argument order (for use with fold etc.);
  5433 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5434 
  5435 * Pure/General: output via the Isabelle channels of
  5436 writeln/warning/error etc. is now passed through Output.output, with a
  5437 hook for arbitrary transformations depending on the print_mode
  5438 (cf. Output.add_mode -- the first active mode that provides a output
  5439 function wins).  Already formatted output may be embedded into further
  5440 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5441 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5442 accommodate easy composition of diagnostic messages etc.  Programmers
  5443 rarely need to care about Output.output or Output.raw at all, with
  5444 some notable exceptions: Output.output is required when bypassing the
  5445 standard channels (writeln etc.), or in token translations to produce
  5446 properly formatted results; Output.raw is required when capturing
  5447 already output material that will eventually be presented to the user
  5448 a second time.  For the default print mode, both Output.output and
  5449 Output.raw have no effect.
  5450 
  5451 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5452 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5453 cumulative results are displayed at the end of a batch session.
  5454 
  5455 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5456 replaced by File.platform_path and File.shell_path (with appropriate
  5457 hooks).  This provides a clean interface for unusual systems where the
  5458 internal and external process view of file names are different.
  5459 
  5460 * Pure: more efficient orders for basic syntactic entities: added
  5461 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5462 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5463 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5464 orders now -- potential INCOMPATIBILITY for code that depends on a
  5465 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5466 Library.sort_strings on result).
  5467 
  5468 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5469 fold_types traverse types/terms from left to right, observing natural
  5470 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5471 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5472 
  5473 * Pure: name spaces have been refined, with significant changes of the
  5474 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5475 to extern(_table).  The plain name entry path is superceded by a
  5476 general 'naming' context, which also includes the 'policy' to produce
  5477 a fully qualified name and external accesses of a fully qualified
  5478 name; NameSpace.extend is superceded by context dependent
  5479 Sign.declare_name.  Several theory and proof context operations modify
  5480 the naming context.  Especially note Theory.restore_naming and
  5481 ProofContext.restore_naming to get back to a sane state; note that
  5482 Theory.add_path is no longer sufficient to recover from
  5483 Theory.absolute_path in particular.
  5484 
  5485 * Pure: new flags short_names (default false) and unique_names
  5486 (default true) for controlling output of qualified names.  If
  5487 short_names is set, names are printed unqualified.  If unique_names is
  5488 reset, the name prefix is reduced to the minimum required to achieve
  5489 the original result when interning again, even if there is an overlap
  5490 with earlier declarations.
  5491 
  5492 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5493 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5494 (useful for printing error messages).  INCOMPATIBILITY.
  5495 
  5496 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5497 Theory.theory are now identified, referring to the universal
  5498 Context.theory (see Pure/context.ML).  Actual signature and theory
  5499 content is managed as theory data.  The old code and interfaces were
  5500 spread over many files and structures; the new arrangement introduces
  5501 considerable INCOMPATIBILITY to gain more clarity:
  5502 
  5503   Context -- theory management operations (name, identity, inclusion,
  5504     parents, ancestors, merge, etc.), plus generic theory data;
  5505 
  5506   Sign -- logical signature and syntax operations (declaring consts,
  5507     types, etc.), plus certify/read for common entities;
  5508 
  5509   Theory -- logical theory operations (stating axioms, definitions,
  5510     oracles), plus a copy of logical signature operations (consts,
  5511     types, etc.); also a few basic management operations (Theory.copy,
  5512     Theory.merge, etc.)
  5513 
  5514 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5515 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5516 for convenience -- they merely return the theory.
  5517 
  5518 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5519 
  5520 * Pure: the Isar proof context type is already defined early in Pure
  5521 as Context.proof (note that ProofContext.context and Proof.context are
  5522 aliases, where the latter is the preferred name).  This enables other
  5523 Isabelle components to refer to that type even before Isar is present.
  5524 
  5525 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5526 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5527 any of these kinds.  For example, Sign.intern typeK is now
  5528 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5529 Theory.hide_types.  Also note that former
  5530 Theory.hide_classes/types/consts are now
  5531 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5532 internalize their arguments!  INCOMPATIBILITY.
  5533 
  5534 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5535 datatype thmref (with constructors Name and NameSelection) instead of
  5536 plain string -- INCOMPATIBILITY;
  5537 
  5538 * Pure: cases produced by proof methods specify options, where NONE
  5539 means to remove case bindings -- INCOMPATIBILITY in
  5540 (RAW_)METHOD_CASES.
  5541 
  5542 * Pure: the following operations retrieve axioms or theorems from a
  5543 theory node or theory hierarchy, respectively:
  5544 
  5545   Theory.axioms_of: theory -> (string * term) list
  5546   Theory.all_axioms_of: theory -> (string * term) list
  5547   PureThy.thms_of: theory -> (string * thm) list
  5548   PureThy.all_thms_of: theory -> (string * thm) list
  5549 
  5550 * Pure: print_tac now outputs the goal through the trace channel.
  5551 
  5552 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5553 Reference Toplevel.debug (default false) controls detailed printing
  5554 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5555 controls execution profiling -- set to 1 for time and 2 for space
  5556 (both increase the runtime).
  5557 
  5558 * Isar session: The initial use of ROOT.ML is now always timed,
  5559 i.e. the log will show the actual process times, in contrast to the
  5560 elapsed wall-clock time that the outer shell wrapper produces.
  5561 
  5562 * Simplifier: improved handling of bound variables (nameless
  5563 representation, avoid allocating new strings).  Simprocs that invoke
  5564 the Simplifier recursively should use Simplifier.inherit_bounds to
  5565 avoid local name clashes.  Failure to do so produces warnings
  5566 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5567 for further details.
  5568 
  5569 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5570 bindings for all theorems stored within a given theory; this may help
  5571 in porting non-Isar theories to Isar ones, while keeping ML proof
  5572 scripts for the time being.
  5573 
  5574 * ML operator HTML.with_charset specifies the charset begin used for
  5575 generated HTML files.  For example:
  5576 
  5577   HTML.with_charset "utf-8" use_thy "Hebrew";
  5578   HTML.with_charset "utf-8" use_thy "Chinese";
  5579 
  5580 
  5581 *** System ***
  5582 
  5583 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5584 isabelle, isatool etc.).
  5585 
  5586 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5587 isatool doc, isatool mkdir, display_drafts etc.).
  5588 
  5589 * isatool usedir: option -f allows specification of the ML file to be
  5590 used by Isabelle; default is ROOT.ML.
  5591 
  5592 * New isatool version outputs the version identifier of the Isabelle
  5593 distribution being used.
  5594 
  5595 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5596 (containing Boolean satisfiability problems) into Isabelle/HOL
  5597 theories.
  5598 
  5599 
  5600 
  5601 New in Isabelle2004 (April 2004)
  5602 --------------------------------
  5603 
  5604 *** General ***
  5605 
  5606 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5607   Replaces linorder.ML.
  5608 
  5609 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5610   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5611   (\<a>...\<z>), are now considered normal letters, and can therefore
  5612   be used anywhere where an ASCII letter (a...zA...Z) has until
  5613   now. COMPATIBILITY: This obviously changes the parsing of some
  5614   terms, especially where a symbol has been used as a binder, say
  5615   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5616   as an identifier.  Fix it by inserting a space around former
  5617   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5618   existing theory and ML files.
  5619 
  5620 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5621 
  5622 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5623   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5624   a normal (but invisible) letter. For multiple letter subscripts repeat
  5625   \<^isub> like this: x\<^isub>1\<^isub>2.
  5626 
  5627 * Pure: There are now sub-/superscripts that can span more than one
  5628   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5629   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5630   superscript. The new control characters are not identifier parts.
  5631 
  5632 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5633   content of "..." to the latex file instead of \isacntrl... . The "..."
  5634   may consist of any printable characters excluding the end bracket >.
  5635 
  5636 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5637   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5638   declare constants "final", which prevents their being given a definition
  5639   later.  It is useful for constants whose behaviour is fixed axiomatically
  5640   rather than definitionally, such as the meta-logic connectives.
  5641 
  5642 * Pure: 'instance' now handles general arities with general sorts
  5643   (i.e. intersections of classes),
  5644 
  5645 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5646   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5647   It can be changed to alter the colors/layout of generated pages.
  5648 
  5649 
  5650 *** Isar ***
  5651 
  5652 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5653   cut_tac, subgoal_tac and thin_tac:
  5654   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5655     locales are no longer forced to write Isar proof scripts.
  5656     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5657     emulations.
  5658   - INCOMPATIBILITY: names of variables to be instantiated may no
  5659     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5660     This is consistent with the instantiation attribute "where".
  5661 
  5662 * Attributes "where" and "of":
  5663   - Now take type variables of instantiated theorem into account when reading
  5664     the instantiation string.  This fixes a bug that caused instantiated
  5665     theorems to have too special types in some circumstances.
  5666   - "where" permits explicit instantiations of type variables.
  5667 
  5668 * Calculation commands "moreover" and "also" no longer interfere with
  5669   current facts ("this"), admitting arbitrary combinations with "then"
  5670   and derived forms.
  5671 
  5672 * Locales:
  5673   - Goal statements involving the context element "includes" no longer
  5674     generate theorems with internal delta predicates (those ending on
  5675     "_axioms") in the premise.
  5676     Resolve particular premise with <locale>.intro to obtain old form.
  5677   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5678     specification and "includes" elements in goal statement.
  5679   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5680     [intro?] and [elim?] (respectively) by default.
  5681   - Experimental command for instantiation of locales in proof contexts:
  5682         instantiate <label>[<attrs>]: <loc>
  5683     Instantiates locale <loc> and adds all its theorems to the current context
  5684     taking into account their attributes.  Label and attrs are optional
  5685     modifiers, like in theorem declarations.  If present, names of
  5686     instantiated theorems are qualified with <label>, and the attributes
  5687     <attrs> are applied after any attributes these theorems might have already.
  5688       If the locale has assumptions, a chained fact of the form
  5689     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5690     are derived.  The command does not support old-style locales declared
  5691     with "locale (open)".
  5692       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5693 
  5694 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5695   (Isar) contexts.
  5696 
  5697 
  5698 *** HOL ***
  5699 
  5700 * Proof import: new image HOL4 contains the imported library from
  5701   the HOL4 system with about 2500 theorems. It is imported by
  5702   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5703   can be used like any other Isabelle image.  See
  5704   HOL/Import/HOL/README for more information.
  5705 
  5706 * Simplifier:
  5707   - Much improved handling of linear and partial orders.
  5708     Reasoners for linear and partial orders are set up for type classes
  5709     "linorder" and "order" respectively, and are added to the default simpset
  5710     as solvers.  This means that the simplifier can build transitivity chains
  5711     to solve goals from the assumptions.
  5712   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5713     of blast or auto after simplification become unnecessary because the goal
  5714     is solved by simplification already.
  5715 
  5716 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5717     all proved in axiomatic type classes for semirings, rings and fields.
  5718 
  5719 * Numerics:
  5720   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5721     now formalized using the Ring_and_Field theory mentioned above.
  5722   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5723     than before, because now they are set up once in a generic manner.
  5724   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5725     Look for the general versions in Ring_and_Field (and Power if they concern
  5726     exponentiation).
  5727 
  5728 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5729 
  5730 * Records:
  5731   - Record types are now by default printed with their type abbreviation
  5732     instead of the list of all field types. This can be configured via
  5733     the reference "print_record_type_abbr".
  5734   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5735     (not enabled by default).
  5736   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5737     EX x. x = sel r to True (not enabled by default).
  5738   - Tactic "record_split_simp_tac" to split and simplify records added.
  5739 
  5740 * 'specification' command added, allowing for definition by
  5741   specification.  There is also an 'ax_specification' command that
  5742   introduces the new constants axiomatically.
  5743 
  5744 * arith(_tac) is now able to generate counterexamples for reals as well.
  5745 
  5746 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5747 
  5748 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5749   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5750 
  5751 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5752   matrix theory to linear programming.
  5753 
  5754 * Unions and Intersections:
  5755   The latex output syntax of UN and INT has been changed
  5756   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5757   i.e. the index formulae has become a subscript.
  5758   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5759 
  5760 * Unions and Intersections over Intervals:
  5761   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5762   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5763   like in normal math, and corresponding versions for < and for intersection.
  5764 
  5765 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5766   lexicographic dictonary ordering has been added as "lexord".
  5767 
  5768 * ML: the legacy theory structures Int and List have been removed. They had
  5769   conflicted with ML Basis Library structures having the same names.
  5770 
  5771 * 'refute' command added to search for (finite) countermodels.  Only works
  5772   for a fragment of HOL.  The installation of an external SAT solver is
  5773   highly recommended.  See "HOL/Refute.thy" for details.
  5774 
  5775 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5776   formulae under an assignment of free variables to random values.
  5777   In contrast to 'refute', it can deal with inductive datatypes,
  5778   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5779   for examples.
  5780 
  5781 
  5782 *** HOLCF ***
  5783 
  5784 * Streams now come with concatenation and are part of the HOLCF image
  5785 
  5786 
  5787 
  5788 New in Isabelle2003 (May 2003)
  5789 ------------------------------
  5790 
  5791 *** General ***
  5792 
  5793 * Provers/simplifier:
  5794 
  5795   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5796     Assumptions are now subject to complete mutual simplification,
  5797     not just from left to right. The simplifier now preserves
  5798     the order of assumptions.
  5799 
  5800     Potential INCOMPATIBILITY:
  5801 
  5802     -- simp sometimes diverges where the old version did
  5803        not, e.g. invoking simp on the goal
  5804 
  5805         [| P (f x); y = x; f x = f y |] ==> Q
  5806 
  5807        now gives rise to the infinite reduction sequence
  5808 
  5809         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5810 
  5811        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5812        kind of problem.
  5813 
  5814     -- Tactics combining classical reasoner and simplification (such as auto)
  5815        are also affected by this change, because many of them rely on
  5816        simp. They may sometimes diverge as well or yield a different numbers
  5817        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5818        in case of problems. Sometimes subsequent calls to the classical
  5819        reasoner will fail because a preceeding call to the simplifier too
  5820        eagerly simplified the goal, e.g. deleted redundant premises.
  5821 
  5822   - The simplifier trace now shows the names of the applied rewrite rules
  5823 
  5824   - You can limit the number of recursive invocations of the simplifier
  5825     during conditional rewriting (where the simplifie tries to solve the
  5826     conditions before applying the rewrite rule):
  5827     ML "simp_depth_limit := n"
  5828     where n is an integer. Thus you can force termination where previously
  5829     the simplifier would diverge.
  5830 
  5831   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5832 
  5833   - No longer aborts on failed congruence proof.  Instead, the
  5834     congruence is ignored.
  5835 
  5836 * Pure: New generic framework for extracting programs from constructive
  5837   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5838   as HOL/Extraction for some case studies.
  5839 
  5840 * Pure: The main goal of the proof state is no longer shown by default, only
  5841 the subgoals. This behaviour is controlled by a new flag.
  5842    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5843 (ML: Proof.show_main_goal).
  5844 
  5845 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5846 rules whose conclusion matches subgoal 1:
  5847       PG menu: Isabelle/Isar -> Show me -> matching rules
  5848 The rules are ordered by how closely they match the subgoal.
  5849 In particular, rules that solve a subgoal outright are displayed first
  5850 (or rather last, the way they are printed).
  5851 (ML: ProofGeneral.print_intros())
  5852 
  5853 * Pure: New flag trace_unify_fail causes unification to print
  5854 diagnostic information (PG: in trace buffer) when it fails. This is
  5855 useful for figuring out why single step proofs like rule, erule or
  5856 assumption failed.
  5857 
  5858 * Pure: Locale specifications now produce predicate definitions
  5859 according to the body of text (covering assumptions modulo local
  5860 definitions); predicate "loc_axioms" covers newly introduced text,
  5861 while "loc" is cumulative wrt. all included locale expressions; the
  5862 latter view is presented only on export into the global theory
  5863 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5864 on the old view without predicates;
  5865 
  5866 * Pure: predefined locales "var" and "struct" are useful for sharing
  5867 parameters (as in CASL, for example); just specify something like
  5868 ``var x + var y + struct M'' as import;
  5869 
  5870 * Pure: improved thms_containing: proper indexing of facts instead of
  5871 raw theorems; check validity of results wrt. current name space;
  5872 include local facts of proof configuration (also covers active
  5873 locales), cover fixed variables in index; may use "_" in term
  5874 specification; an optional limit for the number of printed facts may
  5875 be given (the default is 40);
  5876 
  5877 * Pure: disallow duplicate fact bindings within new-style theory files
  5878 (batch-mode only);
  5879 
  5880 * Provers: improved induct method: assumptions introduced by case
  5881 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5882 the goal statement); "foo" still refers to all facts collectively;
  5883 
  5884 * Provers: the function blast.overloaded has been removed: all constants
  5885 are regarded as potentially overloaded, which improves robustness in exchange
  5886 for slight decrease in efficiency;
  5887 
  5888 * Provers/linorder: New generic prover for transitivity reasoning over
  5889 linear orders.  Note: this prover is not efficient!
  5890 
  5891 * Isar: preview of problems to finish 'show' now produce an error
  5892 rather than just a warning (in interactive mode);
  5893 
  5894 
  5895 *** HOL ***
  5896 
  5897 * arith(_tac)
  5898 
  5899  - Produces a counter example if it cannot prove a goal.
  5900    Note that the counter example may be spurious if the goal is not a formula
  5901    of quantifier-free linear arithmetic.
  5902    In ProofGeneral the counter example appears in the trace buffer.
  5903 
  5904  - Knows about div k and mod k where k is a numeral of type nat or int.
  5905 
  5906  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5907    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5908    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5909 
  5910 * simp's arithmetic capabilities have been enhanced a bit: it now
  5911 takes ~= in premises into account (by performing a case split);
  5912 
  5913 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5914 are distributed over a sum of terms;
  5915 
  5916 * New tactic "trans_tac" and method "trans" instantiate
  5917 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5918 "<=", "<" and "=").
  5919 
  5920 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5921 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5922 
  5923 * 'typedef' command has new option "open" to suppress the set
  5924 definition;
  5925 
  5926 * functions Min and Max on finite sets have been introduced (theory
  5927 Finite_Set);
  5928 
  5929 * attribute [symmetric] now works for relations as well; it turns
  5930 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5931 
  5932 * induct over a !!-quantified statement (say !!x1..xn):
  5933   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5934 
  5935 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5936 %x. None. Warning: empty_def now refers to the previously hidden definition
  5937 of the empty set.
  5938 
  5939 * Algebra: formalization of classical algebra.  Intended as base for
  5940 any algebraic development in Isabelle.  Currently covers group theory
  5941 (up to Sylow's theorem) and ring theory (Universal Property of
  5942 Univariate Polynomials).  Contributions welcome;
  5943 
  5944 * GroupTheory: deleted, since its material has been moved to Algebra;
  5945 
  5946 * Complex: new directory of the complex numbers with numeric constants,
  5947 nonstandard complex numbers, and some complex analysis, standard and
  5948 nonstandard (Jacques Fleuriot);
  5949 
  5950 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  5951 
  5952 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  5953 Fleuriot);
  5954 
  5955 * Real/HahnBanach: updated and adapted to locales;
  5956 
  5957 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  5958 Gray and Kramer);
  5959 
  5960 * UNITY: added the Meier-Sanders theory of progress sets;
  5961 
  5962 * MicroJava: bytecode verifier and lightweight bytecode verifier
  5963 as abstract algorithms, instantiated to the JVM;
  5964 
  5965 * Bali: Java source language formalization. Type system, operational
  5966 semantics, axiomatic semantics. Supported language features:
  5967 classes, interfaces, objects,virtual methods, static methods,
  5968 static/instance fields, arrays, access modifiers, definite
  5969 assignment, exceptions.
  5970 
  5971 
  5972 *** ZF ***
  5973 
  5974 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  5975 universe, etc.);
  5976 
  5977 * Main ZF: virtually all theories converted to new-style format;
  5978 
  5979 
  5980 *** ML ***
  5981 
  5982 * Pure: Tactic.prove provides sane interface for internal proofs;
  5983 omits the infamous "standard" operation, so this is more appropriate
  5984 than prove_goalw_cterm in many situations (e.g. in simprocs);
  5985 
  5986 * Pure: improved error reporting of simprocs;
  5987 
  5988 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  5989 up simprocs;
  5990 
  5991 
  5992 *** Document preparation ***
  5993 
  5994 * uses \par instead of \\ for line breaks in theory text. This may
  5995 shift some page breaks in large documents. To get the old behaviour
  5996 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  5997 
  5998 * minimized dependencies of isabelle.sty and isabellesym.sty on
  5999 other packages
  6000 
  6001 * \<euro> now needs package babel/greek instead of marvosym (which
  6002 broke \Rightarrow)
  6003 
  6004 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  6005 textcomp package)
  6006 
  6007 
  6008 
  6009 New in Isabelle2002 (March 2002)
  6010 --------------------------------
  6011 
  6012 *** Document preparation ***
  6013 
  6014 * greatly simplified document preparation setup, including more
  6015 graceful interpretation of isatool usedir -i/-d/-D options, and more
  6016 instructive isatool mkdir; users should basically be able to get
  6017 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  6018 users may run a separate document processing stage manually like this:
  6019 "isatool usedir -D output HOL Test && isatool document Test/output";
  6020 
  6021 * theory dependency graph may now be incorporated into documents;
  6022 isatool usedir -g true will produce session_graph.eps/.pdf for use
  6023 with \includegraphics of LaTeX;
  6024 
  6025 * proper spacing of consecutive markup elements, especially text
  6026 blocks after section headings;
  6027 
  6028 * support bold style (for single symbols only), input syntax is like
  6029 this: "\<^bold>\<alpha>" or "\<^bold>A";
  6030 
  6031 * \<bullet> is now output as bold \cdot by default, which looks much
  6032 better in printed text;
  6033 
  6034 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  6035 note that these symbols are currently unavailable in Proof General /
  6036 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  6037 
  6038 * isatool latex no longer depends on changed TEXINPUTS, instead
  6039 isatool document copies the Isabelle style files to the target
  6040 location;
  6041 
  6042 
  6043 *** Isar ***
  6044 
  6045 * Pure/Provers: improved proof by cases and induction;
  6046   - 'case' command admits impromptu naming of parameters (such as
  6047     "case (Suc n)");
  6048   - 'induct' method divinates rule instantiation from the inductive
  6049     claim; no longer requires excessive ?P bindings for proper
  6050     instantiation of cases;
  6051   - 'induct' method properly enumerates all possibilities of set/type
  6052     rules; as a consequence facts may be also passed through *type*
  6053     rules without further ado;
  6054   - 'induct' method now derives symbolic cases from the *rulified*
  6055     rule (before it used to rulify cases stemming from the internal
  6056     atomized version); this means that the context of a non-atomic
  6057     statement becomes is included in the hypothesis, avoiding the
  6058     slightly cumbersome show "PROP ?case" form;
  6059   - 'induct' may now use elim-style induction rules without chaining
  6060     facts, using ``missing'' premises from the goal state; this allows
  6061     rules stemming from inductive sets to be applied in unstructured
  6062     scripts, while still benefitting from proper handling of non-atomic
  6063     statements; NB: major inductive premises need to be put first, all
  6064     the rest of the goal is passed through the induction;
  6065   - 'induct' proper support for mutual induction involving non-atomic
  6066     rule statements (uses the new concept of simultaneous goals, see
  6067     below);
  6068   - append all possible rule selections, but only use the first
  6069     success (no backtracking);
  6070   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  6071   - undeclared rule case names default to numbers 1, 2, 3, ...;
  6072   - added 'print_induct_rules' (covered by help item in recent Proof
  6073     General versions);
  6074   - moved induct/cases attributes to Pure, methods to Provers;
  6075   - generic method setup instantiated for FOL and HOL;
  6076 
  6077 * Pure: support multiple simultaneous goal statements, for example
  6078 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  6079 meta-level mechanism, this acts as if several individual goals had
  6080 been stated separately; in particular common proof methods need to be
  6081 repeated in order to cover all claims; note that a single elimination
  6082 step is *not* sufficient to establish the two conjunctions, so this
  6083 fails:
  6084 
  6085   assume "A & B" then have A and B ..   (*".." fails*)
  6086 
  6087 better use "obtain" in situations as above; alternative refer to
  6088 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  6089 
  6090 * Pure: proper integration with ``locales''; unlike the original
  6091 version by Florian Kammller, Isar locales package high-level proof
  6092 contexts rather than raw logical ones (e.g. we admit to include
  6093 attributes everywhere); operations on locales include merge and
  6094 rename; support for implicit arguments (``structures''); simultaneous
  6095 type-inference over imports and text; see also HOL/ex/Locales.thy for
  6096 some examples;
  6097 
  6098 * Pure: the following commands have been ``localized'', supporting a
  6099 target locale specification "(in name)": 'lemma', 'theorem',
  6100 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  6101 stored both within the locale and at the theory level (exported and
  6102 qualified by the locale name);
  6103 
  6104 * Pure: theory goals may now be specified in ``long'' form, with
  6105 ad-hoc contexts consisting of arbitrary locale elements. for example
  6106 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  6107 definitions may be given, too); the result is a meta-level rule with
  6108 the context elements being discharged in the obvious way;
  6109 
  6110 * Pure: new proof command 'using' allows to augment currently used
  6111 facts after a goal statement ('using' is syntactically analogous to
  6112 'apply', but acts on the goal's facts only); this allows chained facts
  6113 to be separated into parts given before and after a claim, as in
  6114 ``from a and b have C using d and e <proof>'';
  6115 
  6116 * Pure: renamed "antecedent" case to "rule_context";
  6117 
  6118 * Pure: new 'judgment' command records explicit information about the
  6119 object-logic embedding (used by several tools internally); no longer
  6120 use hard-wired "Trueprop";
  6121 
  6122 * Pure: added 'corollary' command;
  6123 
  6124 * Pure: fixed 'token_translation' command;
  6125 
  6126 * Pure: removed obsolete 'exported' attribute;
  6127 
  6128 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  6129 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  6130 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  6131 
  6132 * Pure: method 'atomize' presents local goal premises as object-level
  6133 statements (atomic meta-level propositions); setup controlled via
  6134 rewrite rules declarations of 'atomize' attribute; example
  6135 application: 'induct' method with proper rule statements in improper
  6136 proof *scripts*;
  6137 
  6138 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  6139 now consider the syntactic context of assumptions, giving a better
  6140 chance to get type-inference of the arguments right (this is
  6141 especially important for locales);
  6142 
  6143 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  6144 mode;
  6145 
  6146 * Pure/obtain: the formal conclusion "thesis", being marked as
  6147 ``internal'', may no longer be reference directly in the text;
  6148 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  6149 situations;
  6150 
  6151 * Pure: generic 'sym' attribute which declares a rule both as pure
  6152 'elim?' and for the 'symmetric' operation;
  6153 
  6154 * Pure: marginal comments ``--'' may now occur just anywhere in the
  6155 text; the fixed correlation with particular command syntax has been
  6156 discontinued;
  6157 
  6158 * Pure: new method 'rules' is particularly well-suited for proof
  6159 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  6160 but often produces more compact proof terms with less detours;
  6161 
  6162 * Pure/Provers/classical: simplified integration with pure rule
  6163 attributes and methods; the classical "intro?/elim?/dest?"
  6164 declarations coincide with the pure ones; the "rule" method no longer
  6165 includes classically swapped intros; "intro" and "elim" methods no
  6166 longer pick rules from the context; also got rid of ML declarations
  6167 AddXIs/AddXEs/AddXDs; all of this has some potential for
  6168 INCOMPATIBILITY;
  6169 
  6170 * Provers/classical: attribute 'swapped' produces classical inversions
  6171 of introduction rules;
  6172 
  6173 * Provers/simplifier: 'simplified' attribute may refer to explicit
  6174 rules instead of full simplifier context; 'iff' attribute handles
  6175 conditional rules;
  6176 
  6177 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  6178 
  6179 * HOL: 'recdef' now fails on unfinished automated proofs, use
  6180 "(permissive)" option to recover old behavior;
  6181 
  6182 * HOL: 'inductive' no longer features separate (collective) attributes
  6183 for 'intros' (was found too confusing);
  6184 
  6185 * HOL: properly declared induction rules less_induct and
  6186 wf_induct_rule;
  6187 
  6188 
  6189 *** HOL ***
  6190 
  6191 * HOL: moved over to sane numeral syntax; the new policy is as
  6192 follows:
  6193 
  6194   - 0 and 1 are polymorphic constants, which are defined on any
  6195   numeric type (nat, int, real etc.);
  6196 
  6197   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  6198   binary representation internally;
  6199 
  6200   - type nat has special constructor Suc, and generally prefers Suc 0
  6201   over 1::nat and Suc (Suc 0) over 2::nat;
  6202 
  6203 This change may cause significant problems of INCOMPATIBILITY; here
  6204 are some hints on converting existing sources:
  6205 
  6206   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  6207   entities, so expressions involving "-" (unary or binary minus) need
  6208   to be spaced properly;
  6209 
  6210   - existing occurrences of "1" may need to be constraint "1::nat" or
  6211   even replaced by Suc 0; similar for old "2";
  6212 
  6213   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  6214 
  6215   - remove all special provisions on numerals in proofs;
  6216 
  6217 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  6218 representation (depends on bin_arith_simps in the default context);
  6219 
  6220 * HOL: symbolic syntax for x^2 (numeral 2);
  6221 
  6222 * HOL: the class of all HOL types is now called "type" rather than
  6223 "term"; INCOMPATIBILITY, need to adapt references to this type class
  6224 in axclass/classes, instance/arities, and (usually rare) occurrences
  6225 in typings (of consts etc.); internally the class is called
  6226 "HOL.type", ML programs should refer to HOLogic.typeS;
  6227 
  6228 * HOL/record package improvements:
  6229   - new derived operations "fields" to build a partial record section,
  6230     "extend" to promote a fixed record to a record scheme, and
  6231     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  6232     declared as simp by default;
  6233   - shared operations ("more", &