NEWS
author wenzelm
Fri, 20 May 2011 20:44:03 +0200
changeset 43772 6bc8a6dcb3e0
parent 43743 f115492c7c8d
child 44047 831d28439b3a
permissions -rw-r--r--
added Isabelle_Process.is_active;
tuned signature;
     1 Isabelle NEWS -- history user-relevant changes
     2 ==============================================
     3 
     4 New in this Isabelle version
     5 ----------------------------
     6 
     7 *** General ***
     8 
     9 * Theory loader: source files are identified by content via SHA1
    10 digests.  Discontinued former path/modtime identification and optional
    11 ISABELLE_FILE_IDENT plugin scripts.
    12 
    13 * Parallelization of nested Isar proofs is subject to
    14 Goal.parallel_proofs_threshold (default 100).  See also isabelle
    15 usedir option -Q.
    16 
    17 * Discontinued support for Poly/ML 5.2, which was the last version
    18 without proper multithreading and TimeLimit implementation.
    19 
    20 * Discontinued old lib/scripts/polyml-platform, which has been
    21 obsolete since Isabelle2009-2.
    22 
    23 * Theory loader: source files are exclusively located via the master
    24 directory of each theory node (where the .thy file itself resides).
    25 The global load path (such as src/HOL/Library) is has been
    26 discontinued.  INCOMPATIBILITY.
    27 
    28 * Various optional external tools are referenced more robustly and
    29 uniformly by explicit Isabelle settings as follows:
    30 
    31   ISABELLE_CSDP   (formerly CSDP_EXE)
    32   ISABELLE_GHC    (formerly EXEC_GHC or GHC_PATH)
    33   ISABELLE_OCAML  (formerly EXEC_OCAML)
    34   ISABELLE_SWIPL  (formerly EXEC_SWIPL)
    35   ISABELLE_YAP    (formerly EXEC_YAP)
    36 
    37 Note that automated detection from the file-system or search path has
    38 been discontinued.  INCOMPATIBILITY.
    39 
    40 * Name space: former unsynchronized references are now proper
    41 configuration options, with more conventional names:
    42 
    43   long_names   ~> names_long
    44   short_names  ~> names_short
    45   unique_names ~> names_unique
    46 
    47 Minor INCOMPATIBILITY, need to declare options in context like this:
    48 
    49   declare [[names_unique = false]]
    50 
    51 * Literal facts `prop` may contain dummy patterns, e.g. `_ = _`.  Note
    52 that the result needs to be unique, which means fact specifications
    53 may have to be refined after enriching a proof context.
    54 
    55 * Isabelle/Isar reference manual provides more formal references in
    56 syntax diagrams.
    57 
    58 
    59 *** HOL ***
    60 
    61 * Finite_Set.thy: more coherent development of fold_set locales:
    62 
    63     locale fun_left_comm ~> locale comp_fun_commute
    64     locale fun_left_comm_idem ~> locale comp_fun_idem
    65     
    66 Both use point-free characterisation; interpretation proofs may need adjustment.
    67 INCOMPATIBILITY.
    68 
    69 * Code generation:
    70   - theory Library/Code_Char_ord provides native ordering of characters
    71     in the target language.
    72     
    73 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
    74 
    75 * Nitpick:
    76   - Added "need" and "total_consts" options.
    77   - Reintroduced "show_skolems" option by popular demand.
    78   - Renamed attribute: nitpick_def ~> nitpick_unfold.
    79     INCOMPATIBILITY.
    80 
    81 * Sledgehammer:
    82   - sledgehammer available_provers ~> sledgehammer supported_provers
    83     INCOMPATIBILITY.
    84   - Added support for SNARK and ToFoF-E on SystemOnTPTP and for simply typed
    85     TPTP problems (TFF).
    86   - Added "type_sys", "max_mono_iters", and "max_new_mono_instances" options.
    87 
    88 * "try":
    89   - Added "simp:", "intro:", and "elim:" options.
    90 
    91 * Quickcheck:
    92   - Added "eval" option to evaluate terms for the found counterexample
    93     (currently only supported by the default (exhaustive) tester)
    94   - Added post-processing of terms to obtain readable counterexamples
    95     (currently only supported by the default (exhaustive) tester)
    96 
    97 * Function package: discontinued option "tailrec".
    98 INCOMPATIBILITY. Use partial_function instead.
    99 
   100 * HOL-Probability:
   101   - Caratheodory's extension lemma is now proved for ring_of_sets.
   102   - Infinite products of probability measures are now available.
   103   - Use extended reals instead of positive extended reals.
   104     INCOMPATIBILITY.
   105 
   106 
   107 *** Document preparation ***
   108 
   109 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
   110 isar-ref manual.
   111 
   112 * Localized \isabellestyle switch can be used within blocks or groups
   113 like this:
   114 
   115   \isabellestyle{it}  %preferred default
   116   {\isabellestylett @{text "typewriter stuff"}}
   117 
   118 * New term style "isub" as ad-hoc conversion of variables x1, y23 into
   119 subscripted form x\<^isub>1, y\<^isub>2\<^isub>3.
   120 
   121 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
   122 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
   123 
   124 
   125 *** ML ***
   126 
   127 * Isabelle_Process.is_active allows tools to check if the official
   128 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
   129 (better known as Proof General).
   130 
   131 * Structure Proof_Context follows standard naming scheme.  Old
   132 ProofContext is still available for some time as legacy alias.
   133 
   134 * Structure Timing provides various operations for timing; supersedes
   135 former start_timing/end_timing etc.
   136 
   137 * Path.print is the official way to show file-system paths to users
   138 (including quotes etc.).
   139 
   140 * Inner syntax: identifiers in parse trees of generic categories
   141 "logic", "aprop", "idt" etc. carry position information (disguised as
   142 type constraints).  Occasional INCOMPATIBILITY with non-compliant
   143 translations that choke on unexpected type constraints.  Positions can
   144 be stripped in ML translations via Syntax.strip_positions /
   145 Syntax.strip_positions_ast, or via the syntax constant
   146 "_strip_positions" within parse trees.  As last resort, positions can
   147 be disabled via the configuration option Syntax.positions, which is
   148 called "syntax_positions" in Isar attribute syntax.
   149 
   150 * Discontinued special status of various ML structures that contribute
   151 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
   152 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
   153 refer directly to Ast.Constant, Lexicon.is_identifier,
   154 Syntax_Trans.mk_binder_tr etc.
   155 
   156 * Typed print translation: discontinued show_sorts argument, which is
   157 already available via context of "advanced" translation.
   158 
   159 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
   160 goal states; body tactic needs to address all subgoals uniformly.
   161 
   162 * Slightly more special eq_list/eq_set, with shortcut involving
   163 pointer equality (assumes that eq relation is reflexive).
   164 
   165 * Classical tactics use proper Proof.context instead of historic types
   166 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
   167 operate directly on Proof.context.  Raw type claset retains its use as
   168 snapshot of the classical context, which can be recovered via
   169 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
   170 INCOMPATIBILITY, classical tactics and derived proof methods require
   171 proper Proof.context.
   172 
   173 
   174 
   175 New in Isabelle2011 (January 2011)
   176 ----------------------------------
   177 
   178 *** General ***
   179 
   180 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
   181 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
   182 useful tooltips and hyperlinks produced from its static analysis.  The
   183 bundled component provides an executable Isabelle tool that can be run
   184 like this:
   185 
   186   Isabelle2011/bin/isabelle jedit
   187 
   188 * Significantly improved Isabelle/Isar implementation manual.
   189 
   190 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
   191 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
   192 while the default heap location within that directory lacks that extra
   193 suffix.  This isolates multiple Isabelle installations from each
   194 other, avoiding problems with old settings in new versions.
   195 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
   196 
   197 * Source files are always encoded as UTF-8, instead of old-fashioned
   198 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   199 the following package declarations:
   200 
   201   \usepackage[utf8]{inputenc}
   202   \usepackage{textcomp}
   203 
   204 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   205 a Unicode character is treated as a single symbol, not a sequence of
   206 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   207 contain symbols without further backslash escapes, Unicode can now be
   208 used here as well.  Recall that Symbol.explode in ML provides a
   209 consistent view on symbols, while raw explode (or String.explode)
   210 merely give a byte-oriented representation.
   211 
   212 * Theory loader: source files are primarily located via the master
   213 directory of each theory node (where the .thy file itself resides).
   214 The global load path is still partially available as legacy feature.
   215 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   216 explicit paths, relatively to the theory.
   217 
   218 * Special treatment of ML file names has been discontinued.
   219 Historically, optional extensions .ML or .sml were added on demand --
   220 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   221 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   222 
   223 * Various options that affect pretty printing etc. are now properly
   224 handled within the context via configuration options, instead of
   225 unsynchronized references or print modes.  There are both ML Config.T
   226 entities and Isar declaration attributes to access these.
   227 
   228   ML (Config.T)                 Isar (attribute)
   229 
   230   eta_contract                  eta_contract
   231   show_brackets                 show_brackets
   232   show_sorts                    show_sorts
   233   show_types                    show_types
   234   show_question_marks           show_question_marks
   235   show_consts                   show_consts
   236   show_abbrevs                  show_abbrevs
   237 
   238   Syntax.ast_trace              syntax_ast_trace
   239   Syntax.ast_stat               syntax_ast_stat
   240   Syntax.ambiguity_level        syntax_ambiguity_level
   241 
   242   Goal_Display.goals_limit      goals_limit
   243   Goal_Display.show_main_goal   show_main_goal
   244 
   245   Method.rule_trace             rule_trace
   246 
   247   Thy_Output.display            thy_output_display
   248   Thy_Output.quotes             thy_output_quotes
   249   Thy_Output.indent             thy_output_indent
   250   Thy_Output.source             thy_output_source
   251   Thy_Output.break              thy_output_break
   252 
   253 Note that corresponding "..._default" references in ML may only be
   254 changed globally at the ROOT session setup, but *not* within a theory.
   255 The option "show_abbrevs" supersedes the former print mode
   256 "no_abbrevs" with inverted meaning.
   257 
   258 * More systematic naming of some configuration options.
   259 INCOMPATIBILITY.
   260 
   261   trace_simp  ~>  simp_trace
   262   debug_simp  ~>  simp_debug
   263 
   264 * Support for real valued configuration options, using simplistic
   265 floating-point notation that coincides with the inner syntax for
   266 float_token.
   267 
   268 * Support for real valued preferences (with approximative PGIP type):
   269 front-ends need to accept "pgint" values in float notation.
   270 INCOMPATIBILITY.
   271 
   272 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   273 DejaVu Sans.
   274 
   275 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   276 
   277 
   278 *** Pure ***
   279 
   280 * Command 'type_synonym' (with single argument) replaces somewhat
   281 outdated 'types', which is still available as legacy feature for some
   282 time.
   283 
   284 * Command 'nonterminal' (with 'and' separated list of arguments)
   285 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   286 
   287 * Command 'notepad' replaces former 'example_proof' for
   288 experimentation in Isar without any result.  INCOMPATIBILITY.
   289 
   290 * Locale interpretation commands 'interpret' and 'sublocale' accept
   291 lists of equations to map definitions in a locale to appropriate
   292 entities in the context of the interpretation.  The 'interpretation'
   293 command already provided this functionality.
   294 
   295 * Diagnostic command 'print_dependencies' prints the locale instances
   296 that would be activated if the specified expression was interpreted in
   297 the current context.  Variant "print_dependencies!" assumes a context
   298 without interpretations.
   299 
   300 * Diagnostic command 'print_interps' prints interpretations in proofs
   301 in addition to interpretations in theories.
   302 
   303 * Discontinued obsolete 'global' and 'local' commands to manipulate
   304 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   305 Sign.root_path and Sign.local_path may be applied directly where this
   306 feature is still required for historical reasons.
   307 
   308 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   309 'definition' instead.
   310 
   311 * The "prems" fact, which refers to the accidental collection of
   312 foundational premises in the context, is now explicitly marked as
   313 legacy feature and will be discontinued soon.  Consider using "assms"
   314 of the head statement or reference facts by explicit names.
   315 
   316 * Document antiquotations @{class} and @{type} print classes and type
   317 constructors.
   318 
   319 * Document antiquotation @{file} checks file/directory entries within
   320 the local file system.
   321 
   322 
   323 *** HOL ***
   324 
   325 * Coercive subtyping: functions can be declared as coercions and type
   326 inference will add them as necessary upon input of a term.  Theory
   327 Complex_Main declares real :: nat => real and real :: int => real as
   328 coercions. A coercion function f is declared like this:
   329 
   330   declare [[coercion f]]
   331 
   332 To lift coercions through type constructors (e.g. from nat => real to
   333 nat list => real list), map functions can be declared, e.g.
   334 
   335   declare [[coercion_map map]]
   336 
   337 Currently coercion inference is activated only in theories including
   338 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   339 the configuration option "coercion_enabled", e.g. it can be enabled in
   340 other theories like this:
   341 
   342   declare [[coercion_enabled]]
   343 
   344 * Command 'partial_function' provides basic support for recursive
   345 function definitions over complete partial orders.  Concrete instances
   346 are provided for i) the option type, ii) tail recursion on arbitrary
   347 types, and iii) the heap monad of Imperative_HOL.  See
   348 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   349 for examples.
   350 
   351 * Function package: f.psimps rules are no longer implicitly declared
   352 as [simp].  INCOMPATIBILITY.
   353 
   354 * Datatype package: theorems generated for executable equality (class
   355 "eq") carry proper names and are treated as default code equations.
   356 
   357 * Inductive package: now offers command 'inductive_simps' to
   358 automatically derive instantiated and simplified equations for
   359 inductive predicates, similar to 'inductive_cases'.
   360 
   361 * Command 'enriched_type' allows to register properties of the
   362 functorial structure of types.
   363 
   364 * Improved infrastructure for term evaluation using code generator
   365 techniques, in particular static evaluation conversions.
   366 
   367 * Code generator: Scala (2.8 or higher) has been added to the target
   368 languages.
   369 
   370 * Code generator: globbing constant expressions "*" and "Theory.*"
   371 have been replaced by the more idiomatic "_" and "Theory._".
   372 INCOMPATIBILITY.
   373 
   374 * Code generator: export_code without explicit file declaration prints
   375 to standard output.  INCOMPATIBILITY.
   376 
   377 * Code generator: do not print function definitions for case
   378 combinators any longer.
   379 
   380 * Code generator: simplification with rules determined with
   381 src/Tools/Code/code_simp.ML and method "code_simp".
   382 
   383 * Code generator for records: more idiomatic representation of record
   384 types.  Warning: records are not covered by ancient SML code
   385 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   386 rep_datatype declaration helps to succeed then:
   387 
   388   record 'a foo = ...
   389   ...
   390   rep_datatype foo_ext ...
   391 
   392 * Records: logical foundation type for records does not carry a
   393 '_type' suffix any longer (obsolete due to authentic syntax).
   394 INCOMPATIBILITY.
   395 
   396 * Quickcheck now by default uses exhaustive testing instead of random
   397 testing.  Random testing can be invoked by "quickcheck [random]",
   398 exhaustive testing by "quickcheck [exhaustive]".
   399 
   400 * Quickcheck instantiates polymorphic types with small finite
   401 datatypes by default. This enables a simple execution mechanism to
   402 handle quantifiers and function equality over the finite datatypes.
   403 
   404 * Quickcheck random generator has been renamed from "code" to
   405 "random".  INCOMPATIBILITY.
   406 
   407 * Quickcheck now has a configurable time limit which is set to 30
   408 seconds by default. This can be changed by adding [timeout = n] to the
   409 quickcheck command. The time limit for Auto Quickcheck is still set
   410 independently.
   411 
   412 * Quickcheck in locales considers interpretations of that locale for
   413 counter example search.
   414 
   415 * Sledgehammer:
   416   - Added "smt" and "remote_smt" provers based on the "smt" proof
   417     method. See the Sledgehammer manual for details ("isabelle doc
   418     sledgehammer").
   419   - Renamed commands:
   420     sledgehammer atp_info ~> sledgehammer running_provers
   421     sledgehammer atp_kill ~> sledgehammer kill_provers
   422     sledgehammer available_atps ~> sledgehammer available_provers
   423     INCOMPATIBILITY.
   424   - Renamed options:
   425     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   426     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   427     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   428     (and "ms" and "min" are no longer supported)
   429     INCOMPATIBILITY.
   430 
   431 * Nitpick:
   432   - Renamed options:
   433     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   434     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   435     INCOMPATIBILITY.
   436   - Added support for partial quotient types.
   437   - Added local versions of the "Nitpick.register_xxx" functions.
   438   - Added "whack" option.
   439   - Allow registration of quotient types as codatatypes.
   440   - Improved "merge_type_vars" option to merge more types.
   441   - Removed unsound "fast_descrs" option.
   442   - Added custom symmetry breaking for datatypes, making it possible to reach
   443     higher cardinalities.
   444   - Prevent the expansion of too large definitions.
   445 
   446 * Proof methods "metis" and "meson" now have configuration options
   447 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   448 to diagnose these tools. E.g.
   449 
   450     using [[metis_trace = true]]
   451 
   452 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   453 manually as command 'solve_direct'.
   454 
   455 * The default SMT solver Z3 must be enabled explicitly (due to
   456 licensing issues) by setting the environment variable
   457 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   458 commercial applications, the SMT solver CVC3 is provided as fall-back;
   459 changing the SMT solver is done via the configuration option
   460 "smt_solver".
   461 
   462 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   463 i.e. "remote_cvc3" and "remote_z3".
   464 
   465 * Added basic SMT support for datatypes, records, and typedefs using
   466 the oracle mode (no proofs).  Direct support of pairs has been dropped
   467 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   468 support for a similar behavior).  Minor INCOMPATIBILITY.
   469 
   470 * Changed SMT configuration options:
   471   - Renamed:
   472     z3_proofs ~> smt_oracle (with inverted meaning)
   473     z3_trace_assms ~> smt_trace_used_facts
   474     INCOMPATIBILITY.
   475   - Added:
   476     smt_verbose
   477     smt_random_seed
   478     smt_datatypes
   479     smt_infer_triggers
   480     smt_monomorph_limit
   481     cvc3_options
   482     remote_cvc3_options
   483     remote_z3_options
   484     yices_options
   485 
   486 * Boogie output files (.b2i files) need to be declared in the theory
   487 header.
   488 
   489 * Simplification procedure "list_to_set_comprehension" rewrites list
   490 comprehensions applied to List.set to set comprehensions.  Occasional
   491 INCOMPATIBILITY, may be deactivated like this:
   492 
   493   declare [[simproc del: list_to_set_comprehension]]
   494 
   495 * Removed old version of primrec package.  INCOMPATIBILITY.
   496 
   497 * Removed simplifier congruence rule of "prod_case", as has for long
   498 been the case with "split".  INCOMPATIBILITY.
   499 
   500 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   501 
   502 * Removed [split_format ... and ... and ...] version of
   503 [split_format].  Potential INCOMPATIBILITY.
   504 
   505 * Predicate "sorted" now defined inductively, with nice induction
   506 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   507 
   508 * Constant "contents" renamed to "the_elem", to free the generic name
   509 contents for other uses.  INCOMPATIBILITY.
   510 
   511 * Renamed class eq and constant eq (for code generation) to class
   512 equal and constant equal, plus renaming of related facts and various
   513 tuning.  INCOMPATIBILITY.
   514 
   515 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   516 
   517 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   518 INCOMPATIBILITY.
   519 
   520 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   521 avoid confusion with finite sets.  INCOMPATIBILITY.
   522 
   523 * Abandoned locales equiv, congruent and congruent2 for equivalence
   524 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   525 for congruent(2)).
   526 
   527 * Some previously unqualified names have been qualified:
   528 
   529   types
   530     bool ~> HOL.bool
   531     nat ~> Nat.nat
   532 
   533   constants
   534     Trueprop ~> HOL.Trueprop
   535     True ~> HOL.True
   536     False ~> HOL.False
   537     op & ~> HOL.conj
   538     op | ~> HOL.disj
   539     op --> ~> HOL.implies
   540     op = ~> HOL.eq
   541     Not ~> HOL.Not
   542     The ~> HOL.The
   543     All ~> HOL.All
   544     Ex ~> HOL.Ex
   545     Ex1 ~> HOL.Ex1
   546     Let ~> HOL.Let
   547     If ~> HOL.If
   548     Ball ~> Set.Ball
   549     Bex ~> Set.Bex
   550     Suc ~> Nat.Suc
   551     Pair ~> Product_Type.Pair
   552     fst ~> Product_Type.fst
   553     snd ~> Product_Type.snd
   554     curry ~> Product_Type.curry
   555     op : ~> Set.member
   556     Collect ~> Set.Collect
   557 
   558 INCOMPATIBILITY.
   559 
   560 * More canonical naming convention for some fundamental definitions:
   561 
   562     bot_bool_eq ~> bot_bool_def
   563     top_bool_eq ~> top_bool_def
   564     inf_bool_eq ~> inf_bool_def
   565     sup_bool_eq ~> sup_bool_def
   566     bot_fun_eq  ~> bot_fun_def
   567     top_fun_eq  ~> top_fun_def
   568     inf_fun_eq  ~> inf_fun_def
   569     sup_fun_eq  ~> sup_fun_def
   570 
   571 INCOMPATIBILITY.
   572 
   573 * More stylized fact names:
   574 
   575   expand_fun_eq ~> fun_eq_iff
   576   expand_set_eq ~> set_eq_iff
   577   set_ext       ~> set_eqI
   578   nat_number    ~> eval_nat_numeral
   579 
   580 INCOMPATIBILITY.
   581 
   582 * Refactoring of code-generation specific operations in theory List:
   583 
   584   constants
   585     null ~> List.null
   586 
   587   facts
   588     mem_iff ~> member_def
   589     null_empty ~> null_def
   590 
   591 INCOMPATIBILITY.  Note that these were not supposed to be used
   592 regularly unless for striking reasons; their main purpose was code
   593 generation.
   594 
   595 Various operations from the Haskell prelude are used for generating
   596 Haskell code.
   597 
   598 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   599 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   600 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   601 
   602 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   603 "*" and "+" respectively.  INCOMPATIBILITY.
   604 
   605 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   606 "Sum_Type.Plus" instead.
   607 
   608 * Constant "split" has been merged with constant "prod_case"; names of
   609 ML functions, facts etc. involving split have been retained so far,
   610 though.  INCOMPATIBILITY.
   611 
   612 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   613 instead.  INCOMPATIBILITY.
   614 
   615 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   616 INCOMPATIBILITY.
   617 
   618 * Former theory Library/Enum is now part of the HOL-Main image.
   619 INCOMPATIBILITY: all constants of the Enum theory now have to be
   620 referred to by its qualified name.
   621 
   622   enum    ~>  Enum.enum
   623   nlists  ~>  Enum.nlists
   624   product ~>  Enum.product
   625 
   626 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   627 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   628 INCOMPATIBILITY.
   629 
   630 * Theory Library/SetsAndFunctions has been split into
   631 Library/Function_Algebras and Library/Set_Algebras; canonical names
   632 for instance definitions for functions; various improvements.
   633 INCOMPATIBILITY.
   634 
   635 * Theory Library/Multiset provides stable quicksort implementation of
   636 sort_key.
   637 
   638 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   639 INCOMPATIBILITY.
   640 
   641 * Session Multivariate_Analysis: introduced a type class for euclidean
   642 space.  Most theorems are now stated in terms of euclidean spaces
   643 instead of finite cartesian products.
   644 
   645   types
   646     real ^ 'n ~>  'a::real_vector
   647               ~>  'a::euclidean_space
   648               ~>  'a::ordered_euclidean_space
   649         (depends on your needs)
   650 
   651   constants
   652      _ $ _        ~> _ $$ _
   653      \<chi> x. _  ~> \<chi>\<chi> x. _
   654      CARD('n)     ~> DIM('a)
   655 
   656 Also note that the indices are now natural numbers and not from some
   657 finite type. Finite cartesian products of euclidean spaces, products
   658 of euclidean spaces the real and complex numbers are instantiated to
   659 be euclidean_spaces.  INCOMPATIBILITY.
   660 
   661 * Session Probability: introduced pextreal as positive extended real
   662 numbers.  Use pextreal as value for measures.  Introduce the
   663 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   664 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   665 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   666 
   667 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   668 INCOMPATIBILITY.
   669 
   670 * Session SPARK (with image HOL-SPARK) provides commands to load and
   671 prove verification conditions generated by the SPARK Ada program
   672 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   673 
   674 
   675 *** HOL-Algebra ***
   676 
   677 * Theorems for additive ring operations (locale abelian_monoid and
   678 descendants) are generated by interpretation from their multiplicative
   679 counterparts.  Names (in particular theorem names) have the mandatory
   680 qualifier 'add'.  Previous theorem names are redeclared for
   681 compatibility.
   682 
   683 * Structure "int_ring" is now an abbreviation (previously a
   684 definition).  This fits more natural with advanced interpretations.
   685 
   686 
   687 *** HOLCF ***
   688 
   689 * The domain package now runs in definitional mode by default: The
   690 former command 'new_domain' is now called 'domain'.  To use the domain
   691 package in its original axiomatic mode, use 'domain (unsafe)'.
   692 INCOMPATIBILITY.
   693 
   694 * The new class "domain" is now the default sort.  Class "predomain"
   695 is an unpointed version of "domain". Theories can be updated by
   696 replacing sort annotations as shown below.  INCOMPATIBILITY.
   697 
   698   'a::type ~> 'a::countable
   699   'a::cpo  ~> 'a::predomain
   700   'a::pcpo ~> 'a::domain
   701 
   702 * The old type class "rep" has been superseded by class "domain".
   703 Accordingly, users of the definitional package must remove any
   704 "default_sort rep" declarations.  INCOMPATIBILITY.
   705 
   706 * The domain package (definitional mode) now supports unpointed
   707 predomain argument types, as long as they are marked 'lazy'. (Strict
   708 arguments must be in class "domain".) For example, the following
   709 domain definition now works:
   710 
   711   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   712 
   713 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   714 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   715 'a option, and 'a list.  Additionally, it configures fixrec and the
   716 domain package to work with these types.  For example:
   717 
   718   fixrec isInl :: "('a + 'b) u -> tr"
   719     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   720 
   721   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   722 
   723 * The "(permissive)" option of fixrec has been replaced with a
   724 per-equation "(unchecked)" option. See
   725 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
   726 
   727 * The "bifinite" class no longer fixes a constant "approx"; the class
   728 now just asserts that such a function exists.  INCOMPATIBILITY.
   729 
   730 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
   731 defines an embedding of type 'a defl into udom by default; instances
   732 of "bifinite" and "domain" classes are available in
   733 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
   734 
   735 * The syntax "REP('a)" has been replaced with "DEFL('a)".
   736 
   737 * The predicate "directed" has been removed.  INCOMPATIBILITY.
   738 
   739 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
   740 
   741 * The function "cprod_map" has been renamed to "prod_map".
   742 INCOMPATIBILITY.
   743 
   744 * The monadic bind operator on each powerdomain has new binder syntax
   745 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
   746 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
   747 
   748 * The infix syntax for binary union on each powerdomain has changed
   749 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
   750 syntax.  INCOMPATIBILITY.
   751 
   752 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
   753 still supported as an input translation.
   754 
   755 * Renamed some theorems (the original names are also still available).
   756 
   757   expand_fun_below   ~> fun_below_iff
   758   below_fun_ext      ~> fun_belowI
   759   expand_cfun_eq     ~> cfun_eq_iff
   760   ext_cfun           ~> cfun_eqI
   761   expand_cfun_below  ~> cfun_below_iff
   762   below_cfun_ext     ~> cfun_belowI
   763   cont2cont_Rep_CFun ~> cont2cont_APP
   764 
   765 * The Abs and Rep functions for various types have changed names.
   766 Related theorem names have also changed to match. INCOMPATIBILITY.
   767 
   768   Rep_CFun  ~> Rep_cfun
   769   Abs_CFun  ~> Abs_cfun
   770   Rep_Sprod ~> Rep_sprod
   771   Abs_Sprod ~> Abs_sprod
   772   Rep_Ssum  ~> Rep_ssum
   773   Abs_Ssum  ~> Abs_ssum
   774 
   775 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   776 been renamed to *_bottom_iff.  INCOMPATIBILITY.
   777 
   778 * Various changes to bisimulation/coinduction with domain package:
   779 
   780   - Definitions of "bisim" constants no longer mention definedness.
   781   - With mutual recursion, "bisim" predicate is now curried.
   782   - With mutual recursion, each type gets a separate coind theorem.
   783   - Variable names in bisim_def and coinduct rules have changed.
   784 
   785 INCOMPATIBILITY.
   786 
   787 * Case combinators generated by the domain package for type "foo" are
   788 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
   789 
   790 * Several theorems have been renamed to more accurately reflect the
   791 names of constants and types involved.  INCOMPATIBILITY.
   792 
   793   thelub_const    ~> lub_const
   794   lub_const       ~> is_lub_const
   795   thelubI         ~> lub_eqI
   796   is_lub_lub      ~> is_lubD2
   797   lubI            ~> is_lub_lub
   798   unique_lub      ~> is_lub_unique
   799   is_ub_lub       ~> is_lub_rangeD1
   800   lub_bin_chain   ~> is_lub_bin_chain
   801   lub_fun         ~> is_lub_fun
   802   thelub_fun      ~> lub_fun
   803   thelub_cfun     ~> lub_cfun
   804   thelub_Pair     ~> lub_Pair
   805   lub_cprod       ~> is_lub_prod
   806   thelub_cprod    ~> lub_prod
   807   minimal_cprod   ~> minimal_prod
   808   inst_cprod_pcpo ~> inst_prod_pcpo
   809   UU_I            ~> bottomI
   810   compact_UU      ~> compact_bottom
   811   deflation_UU    ~> deflation_bottom
   812   finite_deflation_UU ~> finite_deflation_bottom
   813 
   814 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
   815 
   816   sq_ord_less_eq_trans ~> below_eq_trans
   817   sq_ord_eq_less_trans ~> eq_below_trans
   818   refl_less            ~> below_refl
   819   trans_less           ~> below_trans
   820   antisym_less         ~> below_antisym
   821   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
   822   box_less             ~> box_below
   823   rev_trans_less       ~> rev_below_trans
   824   not_less2not_eq      ~> not_below2not_eq
   825   less_UU_iff          ~> below_UU_iff
   826   flat_less_iff        ~> flat_below_iff
   827   adm_less             ~> adm_below
   828   adm_not_less         ~> adm_not_below
   829   adm_compact_not_less ~> adm_compact_not_below
   830   less_fun_def         ~> below_fun_def
   831   expand_fun_less      ~> fun_below_iff
   832   less_fun_ext         ~> fun_belowI
   833   less_discr_def       ~> below_discr_def
   834   discr_less_eq        ~> discr_below_eq
   835   less_unit_def        ~> below_unit_def
   836   less_cprod_def       ~> below_prod_def
   837   prod_lessI           ~> prod_belowI
   838   Pair_less_iff        ~> Pair_below_iff
   839   fst_less_iff         ~> fst_below_iff
   840   snd_less_iff         ~> snd_below_iff
   841   expand_cfun_less     ~> cfun_below_iff
   842   less_cfun_ext        ~> cfun_belowI
   843   injection_less       ~> injection_below
   844   less_up_def          ~> below_up_def
   845   not_Iup_less         ~> not_Iup_below
   846   Iup_less             ~> Iup_below
   847   up_less              ~> up_below
   848   Def_inject_less_eq   ~> Def_below_Def
   849   Def_less_is_eq       ~> Def_below_iff
   850   spair_less_iff       ~> spair_below_iff
   851   less_sprod           ~> below_sprod
   852   spair_less           ~> spair_below
   853   sfst_less_iff        ~> sfst_below_iff
   854   ssnd_less_iff        ~> ssnd_below_iff
   855   fix_least_less       ~> fix_least_below
   856   dist_less_one        ~> dist_below_one
   857   less_ONE             ~> below_ONE
   858   ONE_less_iff         ~> ONE_below_iff
   859   less_sinlD           ~> below_sinlD
   860   less_sinrD           ~> below_sinrD
   861 
   862 
   863 *** FOL and ZF ***
   864 
   865 * All constant names are now qualified internally and use proper
   866 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
   867 
   868 
   869 *** ML ***
   870 
   871 * Antiquotation @{assert} inlines a function bool -> unit that raises
   872 Fail if the argument is false.  Due to inlining the source position of
   873 failed assertions is included in the error output.
   874 
   875 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
   876 text is in practice always evaluated with a stable theory checkpoint.
   877 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
   878 
   879 * Antiquotation @{theory A} refers to theory A from the ancestry of
   880 the current context, not any accidental theory loader state as before.
   881 Potential INCOMPATIBILITY, subtle change in semantics.
   882 
   883 * Syntax.pretty_priority (default 0) configures the required priority
   884 of pretty-printed output and thus affects insertion of parentheses.
   885 
   886 * Syntax.default_root (default "any") configures the inner syntax
   887 category (nonterminal symbol) for parsing of terms.
   888 
   889 * Former exception Library.UnequalLengths now coincides with
   890 ListPair.UnequalLengths.
   891 
   892 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
   893 main functionality is provided by structure Simplifier.
   894 
   895 * Renamed raw "explode" function to "raw_explode" to emphasize its
   896 meaning.  Note that internally to Isabelle, Symbol.explode is used in
   897 almost all situations.
   898 
   899 * Discontinued obsolete function sys_error and exception SYS_ERROR.
   900 See implementation manual for further details on exceptions in
   901 Isabelle/ML.
   902 
   903 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   904 meaning.
   905 
   906 * Renamed structure PureThy to Pure_Thy and moved most of its
   907 operations to structure Global_Theory, to emphasize that this is
   908 rarely-used global-only stuff.
   909 
   910 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
   911 instead (or tracing for high-volume output).
   912 
   913 * Configuration option show_question_marks only affects regular pretty
   914 printing of types and terms, not raw Term.string_of_vname.
   915 
   916 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
   917 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
   918 @{thms} for most purposes.
   919 
   920 * ML structure Unsynchronized is never opened, not even in Isar
   921 interaction mode as before.  Old Unsynchronized.set etc. have been
   922 discontinued -- use plain := instead.  This should be *rare* anyway,
   923 since modern tools always work via official context data, notably
   924 configuration options.
   925 
   926 * Parallel and asynchronous execution requires special care concerning
   927 interrupts.  Structure Exn provides some convenience functions that
   928 avoid working directly with raw Interrupt.  User code must not absorb
   929 interrupts -- intermediate handling (for cleanup etc.) needs to be
   930 followed by re-raising of the original exception.  Another common
   931 source of mistakes are "handle _" patterns, which make the meaning of
   932 the program subject to physical effects of the environment.
   933 
   934 
   935 
   936 New in Isabelle2009-2 (June 2010)
   937 ---------------------------------
   938 
   939 *** General ***
   940 
   941 * Authentic syntax for *all* logical entities (type classes, type
   942 constructors, term constants): provides simple and robust
   943 correspondence between formal entities and concrete syntax.  Within
   944 the parse tree / AST representations, "constants" are decorated by
   945 their category (class, type, const) and spelled out explicitly with
   946 their full internal name.
   947 
   948 Substantial INCOMPATIBILITY concerning low-level syntax declarations
   949 and translations (translation rules and translation functions in ML).
   950 Some hints on upgrading:
   951 
   952   - Many existing uses of 'syntax' and 'translations' can be replaced
   953     by more modern 'type_notation', 'notation' and 'abbreviation',
   954     which are independent of this issue.
   955 
   956   - 'translations' require markup within the AST; the term syntax
   957     provides the following special forms:
   958 
   959       CONST c   -- produces syntax version of constant c from context
   960       XCONST c  -- literally c, checked as constant from context
   961       c         -- literally c, if declared by 'syntax'
   962 
   963     Plain identifiers are treated as AST variables -- occasionally the
   964     system indicates accidental variables via the error "rhs contains
   965     extra variables".
   966 
   967     Type classes and type constructors are marked according to their
   968     concrete syntax.  Some old translations rules need to be written
   969     for the "type" category, using type constructor application
   970     instead of pseudo-term application of the default category
   971     "logic".
   972 
   973   - 'parse_translation' etc. in ML may use the following
   974     antiquotations:
   975 
   976       @{class_syntax c}   -- type class c within parse tree / AST
   977       @{term_syntax c}    -- type constructor c within parse tree / AST
   978       @{const_syntax c}   -- ML version of "CONST c" above
   979       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
   980 
   981   - Literal types within 'typed_print_translations', i.e. those *not*
   982     represented as pseudo-terms are represented verbatim.  Use @{class
   983     c} or @{type_name c} here instead of the above syntax
   984     antiquotations.
   985 
   986 Note that old non-authentic syntax was based on unqualified base
   987 names, so all of the above "constant" names would coincide.  Recall
   988 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
   989 diagnose syntax problems.
   990 
   991 * Type constructors admit general mixfix syntax, not just infix.
   992 
   993 * Concrete syntax may be attached to local entities without a proof
   994 body, too.  This works via regular mixfix annotations for 'fix',
   995 'def', 'obtain' etc. or via the explicit 'write' command, which is
   996 similar to the 'notation' command in theory specifications.
   997 
   998 * Discontinued unnamed infix syntax (legacy feature for many years) --
   999 need to specify constant name and syntax separately.  Internal ML
  1000 datatype constructors have been renamed from InfixName to Infix etc.
  1001 Minor INCOMPATIBILITY.
  1002 
  1003 * Schematic theorem statements need to be explicitly markup as such,
  1004 via commands 'schematic_lemma', 'schematic_theorem',
  1005 'schematic_corollary'.  Thus the relevance of the proof is made
  1006 syntactically clear, which impacts performance in a parallel or
  1007 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  1008 
  1009 * Use of cumulative prems via "!" in some proof methods has been
  1010 discontinued (old legacy feature).
  1011 
  1012 * References 'trace_simp' and 'debug_simp' have been replaced by
  1013 configuration options stored in the context. Enabling tracing (the
  1014 case of debugging is similar) in proofs works via
  1015 
  1016   using [[trace_simp = true]]
  1017 
  1018 Tracing is then active for all invocations of the simplifier in
  1019 subsequent goal refinement steps. Tracing may also still be enabled or
  1020 disabled via the ProofGeneral settings menu.
  1021 
  1022 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  1023 'hide_fact' replace the former 'hide' KIND command.  Minor
  1024 INCOMPATIBILITY.
  1025 
  1026 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  1027 more efficient than combinations with -q1 or -q2.
  1028 
  1029 
  1030 *** Pure ***
  1031 
  1032 * Proofterms record type-class reasoning explicitly, using the
  1033 "unconstrain" operation internally.  This eliminates all sort
  1034 constraints from a theorem and proof, introducing explicit
  1035 OFCLASS-premises.  On the proof term level, this operation is
  1036 automatically applied at theorem boundaries, such that closed proofs
  1037 are always free of sort constraints.  INCOMPATIBILITY for tools that
  1038 inspect proof terms.
  1039 
  1040 * Local theory specifications may depend on extra type variables that
  1041 are not present in the result type -- arguments TYPE('a) :: 'a itself
  1042 are added internally.  For example:
  1043 
  1044   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  1045 
  1046 * Predicates of locales introduced by classes carry a mandatory
  1047 "class" prefix.  INCOMPATIBILITY.
  1048 
  1049 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  1050 
  1051 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  1052 'class' instead.
  1053 
  1054 * Command 'code_reflect' allows to incorporate generated ML code into
  1055 runtime environment; replaces immature code_datatype antiquotation.
  1056 INCOMPATIBILITY.
  1057 
  1058 * Code generator: simple concept for abstract datatypes obeying
  1059 invariants.
  1060 
  1061 * Code generator: details of internal data cache have no impact on the
  1062 user space functionality any longer.
  1063 
  1064 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1065 subgoals.  This is more appropriate for interpretations with 'where'.
  1066 INCOMPATIBILITY.
  1067 
  1068 * Command 'example_proof' opens an empty proof body.  This allows to
  1069 experiment with Isar, without producing any persistent result.
  1070 
  1071 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1072 within a local theory context, with explicit checking of the
  1073 constructors involved (in contrast to the raw 'syntax' versions).
  1074 
  1075 * Commands 'types' and 'typedecl' now work within a local theory
  1076 context -- without introducing dependencies on parameters or
  1077 assumptions, which is not possible in Isabelle/Pure.
  1078 
  1079 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1080 within a local theory context.  Minor INCOMPATIBILITY.
  1081 
  1082 
  1083 *** HOL ***
  1084 
  1085 * Command 'typedef' now works within a local theory context -- without
  1086 introducing dependencies on parameters or assumptions, which is not
  1087 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1088 contain multiple interpretations of local typedefs (with different
  1089 non-emptiness proofs), even in a global theory context.
  1090 
  1091 * New package for quotient types.  Commands 'quotient_type' and
  1092 'quotient_definition' may be used for defining types and constants by
  1093 quotient constructions.  An example is the type of integers created by
  1094 quotienting pairs of natural numbers:
  1095 
  1096   fun
  1097     intrel :: "(nat * nat) => (nat * nat) => bool"
  1098   where
  1099     "intrel (x, y) (u, v) = (x + v = u + y)"
  1100 
  1101   quotient_type int = "nat * nat" / intrel
  1102     by (auto simp add: equivp_def expand_fun_eq)
  1103 
  1104   quotient_definition
  1105     "0::int" is "(0::nat, 0::nat)"
  1106 
  1107 The method "lifting" can be used to lift of theorems from the
  1108 underlying "raw" type to the quotient type.  The example
  1109 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1110 construction and provides a reasoning infrastructure for finite sets.
  1111 
  1112 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1113 clash with new theory Quotient in Main HOL.
  1114 
  1115 * Moved the SMT binding into the main HOL session, eliminating
  1116 separate HOL-SMT session.
  1117 
  1118 * List membership infix mem operation is only an input abbreviation.
  1119 INCOMPATIBILITY.
  1120 
  1121 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1122 for future developements; former Library/Word.thy is still present in
  1123 the AFP entry RSAPPS.
  1124 
  1125 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1126 longer shadowed.  INCOMPATIBILITY.
  1127 
  1128 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1129 INCOMPATIBILITY.
  1130 
  1131 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1132 INCOMPATIBILITY.
  1133 
  1134 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1135 instead.  INCOMPATIBILITY.
  1136 
  1137 * Dropped several real-specific versions of lemmas about floor and
  1138 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1139 instead.  INCOMPATIBILITY.
  1140 
  1141   floor_number_of_eq         ~> floor_number_of
  1142   le_floor_eq_number_of      ~> number_of_le_floor
  1143   le_floor_eq_zero           ~> zero_le_floor
  1144   le_floor_eq_one            ~> one_le_floor
  1145   floor_less_eq_number_of    ~> floor_less_number_of
  1146   floor_less_eq_zero         ~> floor_less_zero
  1147   floor_less_eq_one          ~> floor_less_one
  1148   less_floor_eq_number_of    ~> number_of_less_floor
  1149   less_floor_eq_zero         ~> zero_less_floor
  1150   less_floor_eq_one          ~> one_less_floor
  1151   floor_le_eq_number_of      ~> floor_le_number_of
  1152   floor_le_eq_zero           ~> floor_le_zero
  1153   floor_le_eq_one            ~> floor_le_one
  1154   floor_subtract_number_of   ~> floor_diff_number_of
  1155   floor_subtract_one         ~> floor_diff_one
  1156   ceiling_number_of_eq       ~> ceiling_number_of
  1157   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1158   ceiling_le_zero_eq         ~> ceiling_le_zero
  1159   ceiling_le_eq_one          ~> ceiling_le_one
  1160   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1161   less_ceiling_eq_zero       ~> zero_less_ceiling
  1162   less_ceiling_eq_one        ~> one_less_ceiling
  1163   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1164   ceiling_less_eq_zero       ~> ceiling_less_zero
  1165   ceiling_less_eq_one        ~> ceiling_less_one
  1166   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1167   le_ceiling_eq_zero         ~> zero_le_ceiling
  1168   le_ceiling_eq_one          ~> one_le_ceiling
  1169   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1170   ceiling_subtract_one       ~> ceiling_diff_one
  1171 
  1172 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1173 application of the various fold combinators on finite sets.
  1174 
  1175 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1176 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1177 implementation.  INCOMPATIBILTY.
  1178 
  1179 * Theory Library/Coinductive_List has been removed -- superseded by
  1180 AFP/thys/Coinductive.
  1181 
  1182 * Theory PReal, including the type "preal" and related operations, has
  1183 been removed.  INCOMPATIBILITY.
  1184 
  1185 * Real: new development using Cauchy Sequences.
  1186 
  1187 * Split off theory "Big_Operators" containing setsum, setprod,
  1188 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1189 
  1190 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1191 "Int" etc.  INCOMPATIBILITY.
  1192 
  1193 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1194 
  1195 * New set of rules "ac_simps" provides combined assoc / commute
  1196 rewrites for all interpretations of the appropriate generic locales.
  1197 
  1198 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1199 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1200 appropriate and more consistent names suitable for name prefixes
  1201 within the HOL theories.  INCOMPATIBILITY.
  1202 
  1203 * Some generic constants have been put to appropriate theories:
  1204   - less_eq, less: Orderings
  1205   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1206   - inverse, divide: Rings
  1207 INCOMPATIBILITY.
  1208 
  1209 * More consistent naming of type classes involving orderings (and
  1210 lattices):
  1211 
  1212     lower_semilattice                   ~> semilattice_inf
  1213     upper_semilattice                   ~> semilattice_sup
  1214 
  1215     dense_linear_order                  ~> dense_linorder
  1216 
  1217     pordered_ab_group_add               ~> ordered_ab_group_add
  1218     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1219     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1220     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1221     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1222     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1223     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1224     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1225     pordered_comm_ring                  ~> ordered_comm_ring
  1226     pordered_comm_semiring              ~> ordered_comm_semiring
  1227     pordered_ring                       ~> ordered_ring
  1228     pordered_ring_abs                   ~> ordered_ring_abs
  1229     pordered_semiring                   ~> ordered_semiring
  1230 
  1231     ordered_ab_group_add                ~> linordered_ab_group_add
  1232     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1233     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1234     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1235     ordered_field                       ~> linordered_field
  1236     ordered_field_no_lb                 ~> linordered_field_no_lb
  1237     ordered_field_no_ub                 ~> linordered_field_no_ub
  1238     ordered_field_dense_linear_order    ~> dense_linordered_field
  1239     ordered_idom                        ~> linordered_idom
  1240     ordered_ring                        ~> linordered_ring
  1241     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1242     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1243     ordered_ring_strict                 ~> linordered_ring_strict
  1244     ordered_semidom                     ~> linordered_semidom
  1245     ordered_semiring                    ~> linordered_semiring
  1246     ordered_semiring_1                  ~> linordered_semiring_1
  1247     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1248     ordered_semiring_strict             ~> linordered_semiring_strict
  1249 
  1250   The following slightly odd type classes have been moved to a
  1251   separate theory Library/Lattice_Algebras:
  1252 
  1253     lordered_ab_group_add               ~> lattice_ab_group_add
  1254     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1255     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1256     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1257     lordered_ring                       ~> lattice_ring
  1258 
  1259 INCOMPATIBILITY.
  1260 
  1261 * Refined field classes:
  1262   - classes division_ring_inverse_zero, field_inverse_zero,
  1263     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1264     subsumes former division_by_zero class;
  1265   - numerous lemmas have been ported from field to division_ring.
  1266 INCOMPATIBILITY.
  1267 
  1268 * Refined algebra theorem collections:
  1269   - dropped theorem group group_simps, use algebra_simps instead;
  1270   - dropped theorem group ring_simps, use field_simps instead;
  1271   - proper theorem collection field_simps subsumes former theorem
  1272     groups field_eq_simps and field_simps;
  1273   - dropped lemma eq_minus_self_iff which is a duplicate for
  1274     equal_neg_zero.
  1275 INCOMPATIBILITY.
  1276 
  1277 * Theory Finite_Set and List: some lemmas have been generalized from
  1278 sets to lattices:
  1279 
  1280   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1281   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1282   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1283   union_Union_fold_union        ~> sup_Sup_fold_sup
  1284   Inter_fold_inter              ~> Inf_fold_inf
  1285   Union_fold_union              ~> Sup_fold_sup
  1286   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1287   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1288   INTER_fold_inter              ~> INFI_fold_inf
  1289   UNION_fold_union              ~> SUPR_fold_sup
  1290 
  1291 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1292 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1293 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1294 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1295 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1296 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1297 
  1298 * Reorganized theory Multiset: swapped notation of pointwise and
  1299 multiset order:
  1300 
  1301   - pointwise ordering is instance of class order with standard syntax
  1302     <= and <;
  1303   - multiset ordering has syntax <=# and <#; partial order properties
  1304     are provided by means of interpretation with prefix
  1305     multiset_order;
  1306   - less duplication, less historical organization of sections,
  1307     conversion from associations lists to multisets, rudimentary code
  1308     generation;
  1309   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1310     if needed.
  1311 
  1312 Renamed:
  1313 
  1314   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1315   multi_count_ext  ~>  multiset_ext
  1316   diff_union_inverse2  ~>  diff_union_cancelR
  1317 
  1318 INCOMPATIBILITY.
  1319 
  1320 * Theory Permutation: replaced local "remove" by List.remove1.
  1321 
  1322 * Code generation: ML and OCaml code is decorated with signatures.
  1323 
  1324 * Theory List: added transpose.
  1325 
  1326 * Library/Nat_Bijection.thy is a collection of bijective functions
  1327 between nat and other types, which supersedes the older libraries
  1328 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1329 
  1330   Constants:
  1331   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1332   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1333   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1334   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1335   Countable.pair_encode           ~> prod_encode
  1336   NatIso.prod2nat                 ~> prod_encode
  1337   NatIso.nat2prod                 ~> prod_decode
  1338   NatIso.sum2nat                  ~> sum_encode
  1339   NatIso.nat2sum                  ~> sum_decode
  1340   NatIso.list2nat                 ~> list_encode
  1341   NatIso.nat2list                 ~> list_decode
  1342   NatIso.set2nat                  ~> set_encode
  1343   NatIso.nat2set                  ~> set_decode
  1344 
  1345   Lemmas:
  1346   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1347   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1348   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1349   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1350   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1351   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1352   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1353   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1354   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1355   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1356   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1357   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1358   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1359 
  1360 * Sledgehammer:
  1361   - Renamed ATP commands:
  1362     atp_info     ~> sledgehammer running_atps
  1363     atp_kill     ~> sledgehammer kill_atps
  1364     atp_messages ~> sledgehammer messages
  1365     atp_minimize ~> sledgehammer minimize
  1366     print_atps   ~> sledgehammer available_atps
  1367     INCOMPATIBILITY.
  1368   - Added user's manual ("isabelle doc sledgehammer").
  1369   - Added option syntax and "sledgehammer_params" to customize
  1370     Sledgehammer's behavior.  See the manual for details.
  1371   - Modified the Isar proof reconstruction code so that it produces
  1372     direct proofs rather than proofs by contradiction.  (This feature
  1373     is still experimental.)
  1374   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1375     full-typed mode.
  1376   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1377 
  1378 * Nitpick:
  1379   - Added and implemented "binary_ints" and "bits" options.
  1380   - Added "std" option and implemented support for nonstandard models.
  1381   - Added and implemented "finitize" option to improve the precision
  1382     of infinite datatypes based on a monotonicity analysis.
  1383   - Added support for quotient types.
  1384   - Added support for "specification" and "ax_specification"
  1385     constructs.
  1386   - Added support for local definitions (for "function" and
  1387     "termination" proofs).
  1388   - Added support for term postprocessors.
  1389   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1390   - Improved efficiency of "destroy_constrs" optimization.
  1391   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1392     record getters.
  1393   - Fixed soundness bug related to higher-order constructors.
  1394   - Fixed soundness bug when "full_descrs" is enabled.
  1395   - Improved precision of set constructs.
  1396   - Added "atoms" option.
  1397   - Added cache to speed up repeated Kodkod invocations on the same
  1398     problems.
  1399   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1400     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1401     "SAT4J_Light".  INCOMPATIBILITY.
  1402   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1403     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1404   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1405 
  1406 * Method "induct" now takes instantiations of the form t, where t is not
  1407   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1408   If this is not intended, t has to be enclosed in parentheses.
  1409   By default, the equalities generated by definitional instantiations
  1410   are pre-simplified, which may cause parameters of inductive cases
  1411   to disappear, or may even delete some of the inductive cases.
  1412   Use "induct (no_simp)" instead of "induct" to restore the old
  1413   behaviour. The (no_simp) option is also understood by the "cases"
  1414   and "nominal_induct" methods, which now perform pre-simplification, too.
  1415   INCOMPATIBILITY.
  1416 
  1417 
  1418 *** HOLCF ***
  1419 
  1420 * Variable names in lemmas generated by the domain package have
  1421 changed; the naming scheme is now consistent with the HOL datatype
  1422 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1423 
  1424 * The domain package no longer defines the function "foo_copy" for
  1425 recursive domain "foo".  The reach lemma is now stated directly in
  1426 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1427 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1428 
  1429 * Most definedness lemmas generated by the domain package (previously
  1430 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1431 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1432 Proofs that used definedness lemmas as intro rules may break,
  1433 potential INCOMPATIBILITY.
  1434 
  1435 * Induction and casedist rules generated by the domain package now
  1436 declare proper case_names (one called "bottom", and one named for each
  1437 constructor).  INCOMPATIBILITY.
  1438 
  1439 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1440 rules are generated for each domain, INCOMPATIBILITY.
  1441 
  1442   foo_bar.reach       ~> foo.reach  bar.reach
  1443   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1444 
  1445 * Some lemmas generated by the domain package have been renamed for
  1446 consistency with the datatype package, INCOMPATIBILITY.
  1447 
  1448   foo.ind        ~> foo.induct
  1449   foo.finite_ind ~> foo.finite_induct
  1450   foo.coind      ~> foo.coinduct
  1451   foo.casedist   ~> foo.exhaust
  1452   foo.exhaust    ~> foo.nchotomy
  1453 
  1454 * For consistency with other definition packages, the fixrec package
  1455 now generates qualified theorem names, INCOMPATIBILITY.
  1456 
  1457   foo_simps  ~> foo.simps
  1458   foo_unfold ~> foo.unfold
  1459   foo_induct ~> foo.induct
  1460 
  1461 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1462 method and internal fixrec proofs now use the default simpset instead.
  1463 INCOMPATIBILITY.
  1464 
  1465 * The "contlub" predicate has been removed.  Proof scripts should use
  1466 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1467 
  1468 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1469 
  1470 * The constants cpair, cfst, and csnd have been removed in favor of
  1471 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1472 
  1473 
  1474 *** ML ***
  1475 
  1476 * Antiquotations for basic formal entities:
  1477 
  1478     @{class NAME}         -- type class
  1479     @{class_syntax NAME}  -- syntax representation of the above
  1480 
  1481     @{type_name NAME}     -- logical type
  1482     @{type_abbrev NAME}   -- type abbreviation
  1483     @{nonterminal NAME}   -- type of concrete syntactic category
  1484     @{type_syntax NAME}   -- syntax representation of any of the above
  1485 
  1486     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1487     @{const_abbrev NAME}  -- abbreviated constant
  1488     @{const_syntax NAME}  -- syntax representation of any of the above
  1489 
  1490 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1491 syntax constant (cf. 'syntax' command).
  1492 
  1493 * Antiquotation @{make_string} inlines a function to print arbitrary
  1494 values similar to the ML toplevel.  The result is compiler dependent
  1495 and may fall back on "?" in certain situations.
  1496 
  1497 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1498 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1499 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1500 not work with the asynchronous Isar document model.
  1501 
  1502 * Configuration options now admit dynamic default values, depending on
  1503 the context or even global references.
  1504 
  1505 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1506 uses an efficient external library if available (for Poly/ML).
  1507 
  1508 * Renamed some important ML structures, while keeping the old names
  1509 for some time as aliases within the structure Legacy:
  1510 
  1511   OuterKeyword  ~>  Keyword
  1512   OuterLex      ~>  Token
  1513   OuterParse    ~>  Parse
  1514   OuterSyntax   ~>  Outer_Syntax
  1515   PrintMode     ~>  Print_Mode
  1516   SpecParse     ~>  Parse_Spec
  1517   ThyInfo       ~>  Thy_Info
  1518   ThyLoad       ~>  Thy_Load
  1519   ThyOutput     ~>  Thy_Output
  1520   TypeInfer     ~>  Type_Infer
  1521 
  1522 Note that "open Legacy" simplifies porting of sources, but forgetting
  1523 to remove it again will complicate porting again in the future.
  1524 
  1525 * Most operations that refer to a global context are named
  1526 accordingly, e.g. Simplifier.global_context or
  1527 ProofContext.init_global.  There are some situations where a global
  1528 context actually works, but under normal circumstances one needs to
  1529 pass the proper local context through the code!
  1530 
  1531 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1532 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1533 Pretty.pp argument to merge, which is absent in the standard
  1534 Theory_Data version.
  1535 
  1536 * Sorts.certify_sort and derived "cert" operations for types and terms
  1537 no longer minimize sorts.  Thus certification at the boundary of the
  1538 inference kernel becomes invariant under addition of class relations,
  1539 which is an important monotonicity principle.  Sorts are now minimized
  1540 in the syntax layer only, at the boundary between the end-user and the
  1541 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1542 explicitly in rare situations.
  1543 
  1544 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1545 emphasize that this is in no way a standard operation.
  1546 INCOMPATIBILITY.
  1547 
  1548 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1549 usual for resolution.  Rare INCOMPATIBILITY.
  1550 
  1551 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1552 to emphasize that these only work in a global situation (which is
  1553 quite rare).
  1554 
  1555 * Curried take and drop in library.ML; negative length is interpreted
  1556 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1557 
  1558 * Proof terms: type substitutions on proof constants now use canonical
  1559 order of type variables.  INCOMPATIBILITY for tools working with proof
  1560 terms.
  1561 
  1562 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1563 may no longer carry premises.  User-level specifications are
  1564 transformed accordingly by Thm.add_axiom/add_def.
  1565 
  1566 
  1567 *** System ***
  1568 
  1569 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1570 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1571 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1572 
  1573 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1574 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1575 respectively.
  1576 
  1577 * Old lib/scripts/polyml-platform is superseded by the
  1578 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1579 variant, even on a 64 bit machine.  The following example setting
  1580 prefers 64 bit if available:
  1581 
  1582   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1583 
  1584 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1585 Isabelle/Scala layer for advanced prover interaction and integration.
  1586 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1587 component.
  1588 
  1589 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1590 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1591 similar to the default assignment of the document preparation system
  1592 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1593 provides some operations for direct access to the font without asking
  1594 the user for manual installation.
  1595 
  1596 
  1597 
  1598 New in Isabelle2009-1 (December 2009)
  1599 -------------------------------------
  1600 
  1601 *** General ***
  1602 
  1603 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1604 one backslash should be used, even in ML sources.
  1605 
  1606 
  1607 *** Pure ***
  1608 
  1609 * Locale interpretation propagates mixins along the locale hierarchy.
  1610 The currently only available mixins are the equations used to map
  1611 local definitions to terms of the target domain of an interpretation.
  1612 
  1613 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1614 loc" to print all interpretations of locale "loc" in the theory.
  1615 Interpretations in proofs are not shown.
  1616 
  1617 * Thoroughly revised locales tutorial.  New section on conditional
  1618 interpretation.
  1619 
  1620 * On instantiation of classes, remaining undefined class parameters
  1621 are formally declared.  INCOMPATIBILITY.
  1622 
  1623 
  1624 *** Document preparation ***
  1625 
  1626 * New generalized style concept for printing terms: @{foo (style) ...}
  1627 instead of @{foo_style style ...}  (old form is still retained for
  1628 backward compatibility).  Styles can be also applied for
  1629 antiquotations prop, term_type and typeof.
  1630 
  1631 
  1632 *** HOL ***
  1633 
  1634 * New proof method "smt" for a combination of first-order logic with
  1635 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1636 fixed-size bitvectors; there is also basic support for higher-order
  1637 features (esp. lambda abstractions).  It is an incomplete decision
  1638 procedure based on external SMT solvers using the oracle mechanism;
  1639 for the SMT solver Z3, this method is proof-producing.  Certificates
  1640 are provided to avoid calling the external solvers solely for
  1641 re-checking proofs.  Due to a remote SMT service there is no need for
  1642 installing SMT solvers locally.  See src/HOL/SMT.
  1643 
  1644 * New commands to load and prove verification conditions generated by
  1645 the Boogie program verifier or derived systems (e.g. the Verifying C
  1646 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1647 
  1648 * New counterexample generator tool 'nitpick' based on the Kodkod
  1649 relational model finder.  See src/HOL/Tools/Nitpick and
  1650 src/HOL/Nitpick_Examples.
  1651 
  1652 * New commands 'code_pred' and 'values' to invoke the predicate
  1653 compiler and to enumerate values of inductive predicates.
  1654 
  1655 * A tabled implementation of the reflexive transitive closure.
  1656 
  1657 * New implementation of quickcheck uses generic code generator;
  1658 default generators are provided for all suitable HOL types, records
  1659 and datatypes.  Old quickcheck can be re-activated importing theory
  1660 Library/SML_Quickcheck.
  1661 
  1662 * New testing tool Mirabelle for automated proof tools.  Applies
  1663 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1664 every proof step in a theory.  To be used in batch mode via the
  1665 "mirabelle" utility.
  1666 
  1667 * New proof method "sos" (sum of squares) for nonlinear real
  1668 arithmetic (originally due to John Harison). It requires theory
  1669 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1670 works well in practice on quantifier-free real arithmetic with +, -,
  1671 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1672 inequalities between polynomials.  It makes use of external
  1673 semidefinite programming solvers.  Method "sos" generates a
  1674 certificate that can be pasted into the proof thus avoiding the need
  1675 to call an external tool every time the proof is checked.  See
  1676 src/HOL/Library/Sum_Of_Squares.
  1677 
  1678 * New method "linarith" invokes existing linear arithmetic decision
  1679 procedure only.
  1680 
  1681 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1682 
  1683 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1684 Causes full type information to be output to the ATPs.  This slows
  1685 ATPs down considerably but eliminates a source of unsound "proofs"
  1686 that fail later.
  1687 
  1688 * New method "metisFT": A version of metis that uses full type
  1689 information in order to avoid failures of proof reconstruction.
  1690 
  1691 * New evaluator "approximate" approximates an real valued term using
  1692 the same method as the approximation method.
  1693 
  1694 * Method "approximate" now supports arithmetic expressions as
  1695 boundaries of intervals and implements interval splitting and Taylor
  1696 series expansion.
  1697 
  1698 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1699 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1700 
  1701 * New theory SupInf of the supremum and infimum operators for sets of
  1702 reals.
  1703 
  1704 * New theory Probability, which contains a development of measure
  1705 theory, eventually leading to Lebesgue integration and probability.
  1706 
  1707 * Extended Multivariate Analysis to include derivation and Brouwer's
  1708 fixpoint theorem.
  1709 
  1710 * Reorganization of number theory, INCOMPATIBILITY:
  1711   - new number theory development for nat and int, in theories Divides
  1712     and GCD as well as in new session Number_Theory
  1713   - some constants and facts now suffixed with _nat and _int
  1714     accordingly
  1715   - former session NumberTheory now named Old_Number_Theory, including
  1716     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1717   - moved theory Pocklington from src/HOL/Library to
  1718     src/HOL/Old_Number_Theory
  1719 
  1720 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1721 lcm of finite and infinite sets. It is shown that they form a complete
  1722 lattice.
  1723 
  1724 * Class semiring_div requires superclass no_zero_divisors and proof of
  1725 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1726 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1727 generalized to class semiring_div, subsuming former theorems
  1728 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1729 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1730 INCOMPATIBILITY.
  1731 
  1732 * Refinements to lattice classes and sets:
  1733   - less default intro/elim rules in locale variant, more default
  1734     intro/elim rules in class variant: more uniformity
  1735   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1736     le_inf_iff
  1737   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1738     sup_aci)
  1739   - renamed ACI to inf_sup_aci
  1740   - new class "boolean_algebra"
  1741   - class "complete_lattice" moved to separate theory
  1742     "Complete_Lattice"; corresponding constants (and abbreviations)
  1743     renamed and with authentic syntax:
  1744     Set.Inf ~>    Complete_Lattice.Inf
  1745     Set.Sup ~>    Complete_Lattice.Sup
  1746     Set.INFI ~>   Complete_Lattice.INFI
  1747     Set.SUPR ~>   Complete_Lattice.SUPR
  1748     Set.Inter ~>  Complete_Lattice.Inter
  1749     Set.Union ~>  Complete_Lattice.Union
  1750     Set.INTER ~>  Complete_Lattice.INTER
  1751     Set.UNION ~>  Complete_Lattice.UNION
  1752   - authentic syntax for
  1753     Set.Pow
  1754     Set.image
  1755   - mere abbreviations:
  1756     Set.empty               (for bot)
  1757     Set.UNIV                (for top)
  1758     Set.inter               (for inf, formerly Set.Int)
  1759     Set.union               (for sup, formerly Set.Un)
  1760     Complete_Lattice.Inter  (for Inf)
  1761     Complete_Lattice.Union  (for Sup)
  1762     Complete_Lattice.INTER  (for INFI)
  1763     Complete_Lattice.UNION  (for SUPR)
  1764   - object-logic definitions as far as appropriate
  1765 
  1766 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1767 Un_subset_iff are explicitly deleted as default simp rules; then also
  1768 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1769 deleted to achieve the desired effect.
  1770 
  1771 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1772 rules by default any longer; the same applies to min_max.inf_absorb1
  1773 etc.  INCOMPATIBILITY.
  1774 
  1775 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1776 pred_set_conv by default.  INCOMPATIBILITY.
  1777 
  1778 * Power operations on relations and functions are now one dedicated
  1779 constant "compow" with infix syntax "^^".  Power operation on
  1780 multiplicative monoids retains syntax "^" and is now defined generic
  1781 in class power.  INCOMPATIBILITY.
  1782 
  1783 * Relation composition "R O S" now has a more standard argument order:
  1784 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1785 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1786 break, since the O_assoc rule was not rewritten like this.  Fix using
  1787 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1788 
  1789 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1790 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1791 INCOMPATIBILITY.
  1792 
  1793 * Most rules produced by inductive and datatype package have mandatory
  1794 prefixes.  INCOMPATIBILITY.
  1795 
  1796 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1797 the attribute of the same name.  Each of the theorems in the list
  1798 DERIV_intros assumes composition with an additional function and
  1799 matches a variable to the derivative, which has to be solved by the
  1800 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1801 of most elementary terms.  Former Maclauren.DERIV_tac and
  1802 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1803 INCOMPATIBILITY.
  1804 
  1805 * Code generator attributes follow the usual underscore convention:
  1806     code_unfold     replaces    code unfold
  1807     code_post       replaces    code post
  1808     etc.
  1809   INCOMPATIBILITY.
  1810 
  1811 * Renamed methods:
  1812     sizechange -> size_change
  1813     induct_scheme -> induction_schema
  1814   INCOMPATIBILITY.
  1815 
  1816 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1817 INCOMPATIBILITY, use "undefined" directly.
  1818 
  1819 * Renamed theorems:
  1820     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1821     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1822     Suc_plus1 -> Suc_eq_plus1
  1823     *anti_sym -> *antisym*
  1824     vector_less_eq_def -> vector_le_def
  1825   INCOMPATIBILITY.
  1826 
  1827 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1828 INCOMPATIBILITY.
  1829 
  1830 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1831 INCOMPATIBILITY.
  1832 
  1833 
  1834 *** HOLCF ***
  1835 
  1836 * Theory Representable defines a class "rep" of domains that are
  1837 representable (via an ep-pair) in the universal domain type "udom".
  1838 Instances are provided for all type constructors defined in HOLCF.
  1839 
  1840 * The 'new_domain' command is a purely definitional version of the
  1841 domain package, for representable domains.  Syntax is identical to the
  1842 old domain package.  The 'new_domain' package also supports indirect
  1843 recursion using previously-defined type constructors.  See
  1844 src/HOLCF/ex/New_Domain.thy for examples.
  1845 
  1846 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1847 on the left-hand side of an equation, and then performs
  1848 simplification.  Rewriting is done using rules declared with the
  1849 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1850 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1851 
  1852 * The pattern-match compiler in 'fixrec' can now handle constructors
  1853 with HOL function types.  Pattern-match combinators for the Pair
  1854 constructor are pre-configured.
  1855 
  1856 * The 'fixrec' package now produces better fixed-point induction rules
  1857 for mutually-recursive definitions:  Induction rules have conclusions
  1858 of the form "P foo bar" instead of "P <foo, bar>".
  1859 
  1860 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1861 been renamed to "below".  The name "below" now replaces "less" in many
  1862 theorem names.  (Legacy theorem names using "less" are still supported
  1863 as well.)
  1864 
  1865 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1866 patterns can be used to generate strictness rules, or to make
  1867 functions more strict (much like the bang-patterns supported by the
  1868 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1869 examples.
  1870 
  1871 
  1872 *** ML ***
  1873 
  1874 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1875 errors and run-time exceptions, including detailed source positions.
  1876 
  1877 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1878 identified entries, with some additional information such as source
  1879 position, logical grouping etc.
  1880 
  1881 * Theory and context data is now introduced by the simplified and
  1882 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1883 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1884 copy operation) is still available for some time.
  1885 
  1886 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1887 provides a high-level programming interface to synchronized state
  1888 variables with atomic update.  This works via pure function
  1889 application within a critical section -- its runtime should be as
  1890 short as possible; beware of deadlocks if critical code is nested,
  1891 either directly or indirectly via other synchronized variables!
  1892 
  1893 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1894 wraps raw ML references, explicitly indicating their non-thread-safe
  1895 behaviour.  The Isar toplevel keeps this structure open, to
  1896 accommodate Proof General as well as quick and dirty interactive
  1897 experiments with references.
  1898 
  1899 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1900 parallel tactical reasoning.
  1901 
  1902 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1903 are similar to SUBPROOF, but are slightly more flexible: only the
  1904 specified parts of the subgoal are imported into the context, and the
  1905 body tactic may introduce new subgoals and schematic variables.
  1906 
  1907 * Old tactical METAHYPS, which does not observe the proof context, has
  1908 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1909 or Subgoal.FOCUS etc.
  1910 
  1911 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1912 functors have their own ML name space there is no point to mark them
  1913 separately.)  Minor INCOMPATIBILITY.
  1914 
  1915 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1916 
  1917 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1918 INCOMPATIBILITY.
  1919 
  1920 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1921 mode, which avoids critical setmp.
  1922 
  1923 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1924 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1925 Attrib/Method.setup introduced in Isabelle2009.
  1926 
  1927 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1928 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1929 last resort.  INCOMPATIBILITY.
  1930 
  1931 * Display.pretty_thm now requires a proper context (cf. former
  1932 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1933 or even Display.pretty_thm_without_context as last resort.
  1934 INCOMPATIBILITY.
  1935 
  1936 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1937 Syntax.pretty_typ/term directly, preferably with proper context
  1938 instead of global theory.
  1939 
  1940 
  1941 *** System ***
  1942 
  1943 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1944 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1945 usedir option -q.
  1946 
  1947 * Support for additional "Isabelle components" via etc/components, see
  1948 also the system manual.
  1949 
  1950 * The isabelle makeall tool now operates on all components with
  1951 IsaMakefile, not just hardwired "logics".
  1952 
  1953 * Removed "compress" option from isabelle-process and isabelle usedir;
  1954 this is always enabled.
  1955 
  1956 * Discontinued support for Poly/ML 4.x versions.
  1957 
  1958 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  1959 on a given logic image.  This requires the lighttpd webserver and is
  1960 currently supported on Linux only.
  1961 
  1962 
  1963 
  1964 New in Isabelle2009 (April 2009)
  1965 --------------------------------
  1966 
  1967 *** General ***
  1968 
  1969 * Simplified main Isabelle executables, with less surprises on
  1970 case-insensitive file-systems (such as Mac OS).
  1971 
  1972   - The main Isabelle tool wrapper is now called "isabelle" instead of
  1973     "isatool."
  1974 
  1975   - The former "isabelle" alias for "isabelle-process" has been
  1976     removed (should rarely occur to regular users).
  1977 
  1978   - The former "isabelle-interface" and its alias "Isabelle" have been
  1979     removed (interfaces are now regular Isabelle tools).
  1980 
  1981 Within scripts and make files, the Isabelle environment variables
  1982 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  1983 respectively.  (The latter are still available as legacy feature.)
  1984 
  1985 The old isabelle-interface wrapper could react in confusing ways if
  1986 the interface was uninstalled or changed otherwise.  Individual
  1987 interface tool configuration is now more explicit, see also the
  1988 Isabelle system manual.  In particular, Proof General is now available
  1989 via "isabelle emacs".
  1990 
  1991 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  1992 purge installed copies of Isabelle executables and re-run "isabelle
  1993 install -p ...", or use symlinks.
  1994 
  1995 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  1996 old ~/isabelle, which was slightly non-standard and apt to cause
  1997 surprises on case-insensitive file-systems (such as Mac OS).
  1998 
  1999 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  2000 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  2001 care is required when using older releases of Isabelle.  Note that
  2002 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  2003 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  2004 
  2005 * Proofs of fully specified statements are run in parallel on
  2006 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  2007 a regular 4-core machine, if the initial heap space is made reasonably
  2008 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  2009 
  2010 * The main reference manuals ("isar-ref", "implementation", and
  2011 "system") have been updated and extended.  Formally checked references
  2012 as hyperlinks are now available uniformly.
  2013 
  2014 
  2015 *** Pure ***
  2016 
  2017 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  2018 respects.  The most important changes are listed below.  See the
  2019 Tutorial on Locales ("locales" manual) for details.
  2020 
  2021 - In locale expressions, instantiation replaces renaming.  Parameters
  2022 must be declared in a for clause.  To aid compatibility with previous
  2023 parameter inheritance, in locale declarations, parameters that are not
  2024 'touched' (instantiation position "_" or omitted) are implicitly added
  2025 with their syntax at the beginning of the for clause.
  2026 
  2027 - Syntax from abbreviations and definitions in locales is available in
  2028 locale expressions and context elements.  The latter is particularly
  2029 useful in locale declarations.
  2030 
  2031 - More flexible mechanisms to qualify names generated by locale
  2032 expressions.  Qualifiers (prefixes) may be specified in locale
  2033 expressions, and can be marked as mandatory (syntax: "name!:") or
  2034 optional (syntax "name?:").  The default depends for plain "name:"
  2035 depends on the situation where a locale expression is used: in
  2036 commands 'locale' and 'sublocale' prefixes are optional, in
  2037 'interpretation' and 'interpret' prefixes are mandatory.  The old
  2038 implicit qualifiers derived from the parameter names of a locale are
  2039 no longer generated.
  2040 
  2041 - Command "sublocale l < e" replaces "interpretation l < e".  The
  2042 instantiation clause in "interpretation" and "interpret" (square
  2043 brackets) is no longer available.  Use locale expressions.
  2044 
  2045 - When converting proof scripts, mandatory qualifiers in
  2046 'interpretation' and 'interpret' should be retained by default, even
  2047 if this is an INCOMPATIBILITY compared to former behavior.  In the
  2048 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  2049 in locale expressions range over a single locale instance only.
  2050 
  2051 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  2052 In existing theorem specifications replace the includes element by the
  2053 respective context elements of the included locale, omitting those
  2054 that are already present in the theorem specification.  Multiple
  2055 assume elements of a locale should be replaced by a single one
  2056 involving the locale predicate.  In the proof body, declarations (most
  2057 notably theorems) may be regained by interpreting the respective
  2058 locales in the proof context as required (command "interpret").
  2059 
  2060 If using "includes" in replacement of a target solely because the
  2061 parameter types in the theorem are not as general as in the target,
  2062 consider declaring a new locale with additional type constraints on
  2063 the parameters (context element "constrains").
  2064 
  2065 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2066 
  2067 - Locale interpretation commands no longer attempt to simplify goal.
  2068 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2069 methods intro_locales and unfold_locales to clarify.
  2070 
  2071 - Locale interpretation commands no longer accept interpretation
  2072 attributes.  INCOMPATIBILITY.
  2073 
  2074 * Class declaration: so-called "base sort" must not be given in import
  2075 list any longer, but is inferred from the specification.  Particularly
  2076 in HOL, write
  2077 
  2078     class foo = ...
  2079 
  2080 instead of
  2081 
  2082     class foo = type + ...
  2083 
  2084 * Class target: global versions of theorems stemming do not carry a
  2085 parameter prefix any longer.  INCOMPATIBILITY.
  2086 
  2087 * Class 'instance' command no longer accepts attached definitions.
  2088 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2089 
  2090 * Recovered hiding of consts, which was accidentally broken in
  2091 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2092 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2093 
  2094 * Slightly more coherent Pure syntax, with updated documentation in
  2095 isar-ref manual.  Removed locales meta_term_syntax and
  2096 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2097 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2098 directly in regular applications.
  2099 
  2100 * There is a new syntactic category "float_const" for signed decimal
  2101 fractions (e.g. 123.45 or -123.45).
  2102 
  2103 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2104 interface with 'setup' command instead.
  2105 
  2106 * Command 'local_setup' is similar to 'setup', but operates on a local
  2107 theory context.
  2108 
  2109 * The 'axiomatization' command now only works within a global theory
  2110 context.  INCOMPATIBILITY.
  2111 
  2112 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2113 hypotheses.  Sorts required in the course of reasoning need to be
  2114 covered by the constraints in the initial statement, completed by the
  2115 type instance information of the background theory.  Non-trivial sort
  2116 hypotheses, which rarely occur in practice, may be specified via
  2117 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2118 
  2119   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2120 
  2121 The result contains an implicit sort hypotheses as before --
  2122 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2123 normalization.
  2124 
  2125 * Generalized Isar history, with support for linear undo, direct state
  2126 addressing etc.
  2127 
  2128 * Changed defaults for unify configuration options:
  2129 
  2130   unify_trace_bound = 50 (formerly 25)
  2131   unify_search_bound = 60 (formerly 30)
  2132 
  2133 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2134 
  2135   a) On theory merge, the last set of code equations for a particular
  2136      constant is taken (in accordance with the policy applied by other
  2137      parts of the code generator framework).
  2138 
  2139   b) Code equations stemming from explicit declarations (e.g. code
  2140      attribute) gain priority over default code equations stemming
  2141      from definition, primrec, fun etc.
  2142 
  2143 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2144 
  2145 * Unified theorem tables for both code generators.  Thus [code
  2146 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2147 
  2148 * Command 'find_consts' searches for constants based on type and name
  2149 patterns, e.g.
  2150 
  2151     find_consts "_ => bool"
  2152 
  2153 By default, matching is against subtypes, but it may be restricted to
  2154 the whole type.  Searching by name is possible.  Multiple queries are
  2155 conjunctive and queries may be negated by prefixing them with a
  2156 hyphen:
  2157 
  2158     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2159 
  2160 * New 'find_theorems' criterion "solves" matches theorems that
  2161 directly solve the current goal (modulo higher-order unification).
  2162 
  2163 * Auto solve feature for main theorem statements: whenever a new goal
  2164 is stated, "find_theorems solves" is called; any theorems that could
  2165 solve the lemma directly are listed as part of the goal state.
  2166 Cf. associated options in Proof General Isabelle settings menu,
  2167 enabled by default, with reasonable timeout for pathological cases of
  2168 higher-order unification.
  2169 
  2170 
  2171 *** Document preparation ***
  2172 
  2173 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2174 demanding keyword 'by' and supporting the full method expression
  2175 syntax just like the Isar command 'by'.
  2176 
  2177 
  2178 *** HOL ***
  2179 
  2180 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2181 points Main and Complex_Main remain as before.
  2182 
  2183 * Logic image HOL-Plain provides a minimal HOL with the most important
  2184 tools available (inductive, datatype, primrec, ...).  This facilitates
  2185 experimentation and tool development.  Note that user applications
  2186 (and library theories) should never refer to anything below theory
  2187 Main, as before.
  2188 
  2189 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2190 experimentation due to shorter build times.
  2191 
  2192 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2193 were previously part of former HOL-Complex.  Entry point Hyperreal
  2194 remains valid, but theories formerly using Complex_Main should now use
  2195 new entry point Hypercomplex.
  2196 
  2197 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2198 Posix processes.  Avoids potentially expensive forking of the ML
  2199 process.  New thread-based implementation also works on non-Unix
  2200 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2201 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2202 commands are covered in the isar-ref manual.
  2203 
  2204 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2205 sledgehammer without local ATP installation (Vampire etc.). Other
  2206 provers may be included via suitable ML wrappers, see also
  2207 src/HOL/ATP_Linkup.thy.
  2208 
  2209 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2210 menu.
  2211 
  2212 * The metis method no longer fails because the theorem is too trivial
  2213 (contains the empty clause).
  2214 
  2215 * The metis method now fails in the usual manner, rather than raising
  2216 an exception, if it determines that it cannot prove the theorem.
  2217 
  2218 * Method "coherent" implements a prover for coherent logic (see also
  2219 src/Tools/coherent.ML).
  2220 
  2221 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2222 "undefined" is the right choice to replace "arbitrary", though
  2223 logically there is no difference.  INCOMPATIBILITY.
  2224 
  2225 * Command "value" now integrates different evaluation mechanisms.  The
  2226 result of the first successful evaluation mechanism is printed.  In
  2227 square brackets a particular named evaluation mechanisms may be
  2228 specified (currently, [SML], [code] or [nbe]).  See further
  2229 src/HOL/ex/Eval_Examples.thy.
  2230 
  2231 * Normalization by evaluation now allows non-leftlinear equations.
  2232 Declare with attribute [code nbe].
  2233 
  2234 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2235 as the structured Isar versions "cases" and "induct", cf. the
  2236 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2237 are now presented as a list of individual projections
  2238 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2239 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2240 rare situations a different rule is selected --- notably nested tuple
  2241 elimination instead of former prod.exhaust: use explicit (case_tac t
  2242 rule: prod.exhaust) here.
  2243 
  2244 * Attributes "cases", "induct", "coinduct" support "del" option.
  2245 
  2246 * Removed fact "case_split_thm", which duplicates "case_split".
  2247 
  2248 * The option datatype has been moved to a new theory Option.  Renamed
  2249 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2250 
  2251 * New predicate "strict_mono" classifies strict functions on partial
  2252 orders.  With strict functions on linear orders, reasoning about
  2253 (in)equalities is facilitated by theorems "strict_mono_eq",
  2254 "strict_mono_less_eq" and "strict_mono_less".
  2255 
  2256 * Some set operations are now proper qualified constants with
  2257 authentic syntax.  INCOMPATIBILITY:
  2258 
  2259     op Int ~>   Set.Int
  2260     op Un ~>    Set.Un
  2261     INTER ~>    Set.INTER
  2262     UNION ~>    Set.UNION
  2263     Inter ~>    Set.Inter
  2264     Union ~>    Set.Union
  2265     {} ~>       Set.empty
  2266     UNIV ~>     Set.UNIV
  2267 
  2268 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2269 theory Set.
  2270 
  2271 * Auxiliary class "itself" has disappeared -- classes without any
  2272 parameter are treated as expected by the 'class' command.
  2273 
  2274 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2275 
  2276 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2277 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2278 
  2279 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2280 method "approximation".  It proves formulas on real values by using
  2281 interval arithmetic.  In the formulas are also the transcendental
  2282 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2283 allowed. For examples see
  2284 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2285 
  2286 * Theory "Reflection" now resides in HOL/Library.
  2287 
  2288 * Entry point to Word library now simply named "Word".
  2289 INCOMPATIBILITY.
  2290 
  2291 * Made source layout more coherent with logical distribution
  2292 structure:
  2293 
  2294     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2295     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2296     src/HOL/Library/GCD.thy ~> src/HOL/
  2297     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2298     src/HOL/Library/Parity.thy ~> src/HOL/
  2299     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2300     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2301     src/HOL/Real/Lubs.thy ~> src/HOL/
  2302     src/HOL/Real/PReal.thy ~> src/HOL/
  2303     src/HOL/Real/Rational.thy ~> src/HOL/
  2304     src/HOL/Real/RComplete.thy ~> src/HOL/
  2305     src/HOL/Real/RealDef.thy ~> src/HOL/
  2306     src/HOL/Real/RealPow.thy ~> src/HOL/
  2307     src/HOL/Real/Real.thy ~> src/HOL/
  2308     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2309     src/HOL/Complex/Complex.thy ~> src/HOL/
  2310     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2311     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2312     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2313     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2314     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2315     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2316     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2317     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2318     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2319     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2320     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2321     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2322     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2323     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2324     src/HOL/Real/Float ~> src/HOL/Library/
  2325     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2326     src/HOL/Real/RealVector.thy ~> src/HOL/
  2327 
  2328     src/HOL/arith_data.ML ~> src/HOL/Tools
  2329     src/HOL/hologic.ML ~> src/HOL/Tools
  2330     src/HOL/simpdata.ML ~> src/HOL/Tools
  2331     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2332     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2333     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2334     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2335     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2336     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2337     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2338 
  2339     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2340     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2341     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2342     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2343     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2344     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2345 
  2346 * If methods "eval" and "evaluation" encounter a structured proof
  2347 state with !!/==>, only the conclusion is evaluated to True (if
  2348 possible), avoiding strange error messages.
  2349 
  2350 * Method "sizechange" automates termination proofs using (a
  2351 modification of) the size-change principle.  Requires SAT solver.  See
  2352 src/HOL/ex/Termination.thy for examples.
  2353 
  2354 * Simplifier: simproc for let expressions now unfolds if bound
  2355 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2356 
  2357 * Method "arith": Linear arithmetic now ignores all inequalities when
  2358 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2359 
  2360 * New attribute "arith" for facts that should always be used
  2361 automatically by arithmetic. It is intended to be used locally in
  2362 proofs, e.g.
  2363 
  2364   assumes [arith]: "x > 0"
  2365 
  2366 Global usage is discouraged because of possible performance impact.
  2367 
  2368 * New classes "top" and "bot" with corresponding operations "top" and
  2369 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2370 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2371 
  2372 * Changed definition lemma "less_fun_def" in order to provide an
  2373 instance for preorders on functions; use lemma "less_le" instead.
  2374 INCOMPATIBILITY.
  2375 
  2376 * Theory Orderings: class "wellorder" moved here, with explicit
  2377 induction rule "less_induct" as assumption.  For instantiation of
  2378 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2379 INCOMPATIBILITY.
  2380 
  2381 * Theory Orderings: added class "preorder" as superclass of "order".
  2382 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2383 etc. slightly changed.  Some theorems named order_class.* now named
  2384 preorder_class.*.
  2385 
  2386 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2387 "diag" to "Id_on".
  2388 
  2389 * Theory Finite_Set: added a new fold combinator of type
  2390 
  2391   ('a => 'b => 'b) => 'b => 'a set => 'b
  2392 
  2393 Occasionally this is more convenient than the old fold combinator
  2394 which is now defined in terms of the new one and renamed to
  2395 fold_image.
  2396 
  2397 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2398 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2399 extended with further lemmas!).  At the moment both still exist but
  2400 the former will disappear at some point.
  2401 
  2402 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2403 class recpower.  Type-specific simp rules for various recpower types
  2404 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2405 
  2406 rat_power_0    -> power_0
  2407 rat_power_Suc  -> power_Suc
  2408 realpow_0      -> power_0
  2409 realpow_Suc    -> power_Suc
  2410 complexpow_0   -> power_0
  2411 complexpow_Suc -> power_Suc
  2412 power_poly_0   -> power_0
  2413 power_poly_Suc -> power_Suc
  2414 
  2415 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2416 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2417 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2418 of lemmas from Divides has been generalized from nat to class
  2419 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2420 renames resulting from duplicate elimination:
  2421 
  2422     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2423     zero_dvd_iff ~>         dvd_0_left_iff
  2424     dvd_0 ~>                dvd_0_right
  2425     DIVISION_BY_ZERO_DIV ~> div_by_0
  2426     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2427     mult_div ~>             div_mult_self2_is_id
  2428     mult_mod ~>             mod_mult_self2_is_0
  2429 
  2430 * Theory IntDiv: removed many lemmas that are instances of class-based
  2431 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2432 rename old lemmas as follows:
  2433 
  2434 dvd_diff               -> nat_dvd_diff
  2435 dvd_zminus_iff         -> dvd_minus_iff
  2436 mod_add1_eq            -> mod_add_eq
  2437 mod_mult1_eq           -> mod_mult_right_eq
  2438 mod_mult1_eq'          -> mod_mult_left_eq
  2439 mod_mult_distrib_mod   -> mod_mult_eq
  2440 nat_mod_add_left_eq    -> mod_add_left_eq
  2441 nat_mod_add_right_eq   -> mod_add_right_eq
  2442 nat_mod_div_trivial    -> mod_div_trivial
  2443 nat_mod_mod_trivial    -> mod_mod_trivial
  2444 zdiv_zadd_self1        -> div_add_self1
  2445 zdiv_zadd_self2        -> div_add_self2
  2446 zdiv_zmult_self1       -> div_mult_self2_is_id
  2447 zdiv_zmult_self2       -> div_mult_self1_is_id
  2448 zdvd_triv_left         -> dvd_triv_left
  2449 zdvd_triv_right        -> dvd_triv_right
  2450 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2451 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2452 zmod_zadd_left_eq      -> mod_add_left_eq
  2453 zmod_zadd_right_eq     -> mod_add_right_eq
  2454 zmod_zadd_self1        -> mod_add_self1
  2455 zmod_zadd_self2        -> mod_add_self2
  2456 zmod_zadd1_eq          -> mod_add_eq
  2457 zmod_zdiff1_eq         -> mod_diff_eq
  2458 zmod_zdvd_zmod         -> mod_mod_cancel
  2459 zmod_zmod_cancel       -> mod_mod_cancel
  2460 zmod_zmult_self1       -> mod_mult_self2_is_0
  2461 zmod_zmult_self2       -> mod_mult_self1_is_0
  2462 zmod_1                 -> mod_by_1
  2463 zdiv_1                 -> div_by_1
  2464 zdvd_abs1              -> abs_dvd_iff
  2465 zdvd_abs2              -> dvd_abs_iff
  2466 zdvd_refl              -> dvd_refl
  2467 zdvd_trans             -> dvd_trans
  2468 zdvd_zadd              -> dvd_add
  2469 zdvd_zdiff             -> dvd_diff
  2470 zdvd_zminus_iff        -> dvd_minus_iff
  2471 zdvd_zminus2_iff       -> minus_dvd_iff
  2472 zdvd_zmultD            -> dvd_mult_right
  2473 zdvd_zmultD2           -> dvd_mult_left
  2474 zdvd_zmult_mono        -> mult_dvd_mono
  2475 zdvd_0_right           -> dvd_0_right
  2476 zdvd_0_left            -> dvd_0_left_iff
  2477 zdvd_1_left            -> one_dvd
  2478 zminus_dvd_iff         -> minus_dvd_iff
  2479 
  2480 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2481 
  2482 * The real numbers offer decimal input syntax: 12.34 is translated
  2483 into 1234/10^2. This translation is not reversed upon output.
  2484 
  2485 * Theory Library/Polynomial defines an abstract type 'a poly of
  2486 univariate polynomials with coefficients of type 'a.  In addition to
  2487 the standard ring operations, it also supports div and mod.  Code
  2488 generation is also supported, using list-style constructors.
  2489 
  2490 * Theory Library/Inner_Product defines a class of real_inner for real
  2491 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2492 => real.  Class real_inner is a subclass of real_normed_vector from
  2493 theory RealVector.
  2494 
  2495 * Theory Library/Product_Vector provides instances for the product
  2496 type 'a * 'b of several classes from RealVector and Inner_Product.
  2497 Definitions of addition, subtraction, scalar multiplication, norms,
  2498 and inner products are included.
  2499 
  2500 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2501 addition to the field operations, numerals and case syntax are also
  2502 supported.
  2503 
  2504 * Theory Library/Diagonalize provides constructive version of Cantor's
  2505 first diagonalization argument.
  2506 
  2507 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2508 zlcm (for int); carried together from various gcd/lcm developements in
  2509 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2510 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2511 may recover tupled syntax as follows:
  2512 
  2513     hide (open) const gcd
  2514     abbreviation gcd where
  2515       "gcd == (%(a, b). GCD.gcd a b)"
  2516     notation (output)
  2517       GCD.gcd ("gcd '(_, _')")
  2518 
  2519 The same works for lcm, zgcd, zlcm.
  2520 
  2521 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2522 instantiations for algebraic structures.  Removed some duplicate
  2523 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2524 
  2525 * ML antiquotation @{code} takes a constant as argument and generates
  2526 corresponding code in background and inserts name of the corresponding
  2527 resulting ML value/function/datatype constructor binding in place.
  2528 All occurrences of @{code} with a single ML block are generated
  2529 simultaneously.  Provides a generic and safe interface for
  2530 instrumentalizing code generation.  See
  2531 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2532 In future you ought to refrain from ad-hoc compiling generated SML
  2533 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2534 cannot refer to constants for which user-defined serializations are
  2535 set.  Refer to the corresponding ML counterpart directly in that
  2536 cases.
  2537 
  2538 * Command 'rep_datatype': instead of theorem names the command now
  2539 takes a list of terms denoting the constructors of the type to be
  2540 represented as datatype.  The characteristic theorems have to be
  2541 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2542 have disappeared in favour of existing ones:
  2543 
  2544     unit_induct                 ~> unit.induct
  2545     prod_induct                 ~> prod.induct
  2546     sum_induct                  ~> sum.induct
  2547     Suc_Suc_eq                  ~> nat.inject
  2548     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2549 
  2550 
  2551 *** HOL-Algebra ***
  2552 
  2553 * New locales for orders and lattices where the equivalence relation
  2554 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2555 locales use a record structure with field eq for the equivalence.
  2556 
  2557 * New theory of factorial domains.
  2558 
  2559 * Units_l_inv and Units_r_inv are now simp rules by default.
  2560 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2561 and/or r_inv will now also require deletion of these lemmas.
  2562 
  2563 * Renamed the following theorems, INCOMPATIBILITY:
  2564 
  2565 UpperD ~> Upper_memD
  2566 LowerD ~> Lower_memD
  2567 least_carrier ~> least_closed
  2568 greatest_carrier ~> greatest_closed
  2569 greatest_Lower_above ~> greatest_Lower_below
  2570 one_zero ~> carrier_one_zero
  2571 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2572 
  2573 
  2574 *** HOL-Nominal ***
  2575 
  2576 * Nominal datatypes can now contain type-variables.
  2577 
  2578 * Commands 'nominal_inductive' and 'equivariance' work with local
  2579 theory targets.
  2580 
  2581 * Nominal primrec can now works with local theory targets and its
  2582 specification syntax now conforms to the general format as seen in
  2583 'inductive' etc.
  2584 
  2585 * Method "perm_simp" honours the standard simplifier attributes
  2586 (no_asm), (no_asm_use) etc.
  2587 
  2588 * The new predicate #* is defined like freshness, except that on the
  2589 left hand side can be a set or list of atoms.
  2590 
  2591 * Experimental command 'nominal_inductive2' derives strong induction
  2592 principles for inductive definitions.  In contrast to
  2593 'nominal_inductive', which can only deal with a fixed number of
  2594 binders, it can deal with arbitrary expressions standing for sets of
  2595 atoms to be avoided.  The only inductive definition we have at the
  2596 moment that needs this generalisation is the typing rule for Lets in
  2597 the algorithm W:
  2598 
  2599  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2600  -----------------------------------------------------------------
  2601          Gamma |- Let x be t1 in t2 : T2
  2602 
  2603 In this rule one wants to avoid all the binders that are introduced by
  2604 "close Gamma T1".  We are looking for other examples where this
  2605 feature might be useful.  Please let us know.
  2606 
  2607 
  2608 *** HOLCF ***
  2609 
  2610 * Reimplemented the simplification procedure for proving continuity
  2611 subgoals.  The new simproc is extensible; users can declare additional
  2612 continuity introduction rules with the attribute [cont2cont].
  2613 
  2614 * The continuity simproc now uses a different introduction rule for
  2615 solving continuity subgoals on terms with lambda abstractions.  In
  2616 some rare cases the new simproc may fail to solve subgoals that the
  2617 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2618 Potential INCOMPATIBILITY.
  2619 
  2620 * Command 'fixrec': specification syntax now conforms to the general
  2621 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2622 examples.  INCOMPATIBILITY.
  2623 
  2624 
  2625 *** ZF ***
  2626 
  2627 * Proof of Zorn's Lemma for partial orders.
  2628 
  2629 
  2630 *** ML ***
  2631 
  2632 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2633 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2634 depends on multithreading, so timouts will not work before Poly/ML
  2635 5.2.1!
  2636 
  2637 * High-level support for concurrent ML programming, see
  2638 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2639 particularly convenient to organize independent functional
  2640 computations.  The concept of "synchronized variables" provides a
  2641 higher-order interface for components with shared state, avoiding the
  2642 delicate details of mutexes and condition variables.  (Requires
  2643 Poly/ML 5.2.1 or later.)
  2644 
  2645 * ML bindings produced via Isar commands are stored within the Isar
  2646 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2647 become thread-safe and work with undo as expected (concerning
  2648 top-level bindings, not side-effects on global references).
  2649 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2650 compiler at runtime; really global bindings need to be given outside a
  2651 theory.  (Requires Poly/ML 5.2 or later.)
  2652 
  2653 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2654 context.  Top-level ML bindings are stored within the proof context in
  2655 a purely sequential fashion, disregarding the nested proof structure.
  2656 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2657 proof.  (Requires Poly/ML 5.2 or later.)
  2658 
  2659 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2660 and Method.setup, as well as Isar commands 'attribute_setup' and
  2661 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2662 existing code accordingly, or use plain 'setup' together with old
  2663 Method.add_method.
  2664 
  2665 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2666 to 'a -> thm, while results are always tagged with an authentic oracle
  2667 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2668 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2669 accordingly.  Note that extra performance may be gained by producing
  2670 the cterm carefully, avoiding slow Thm.cterm_of.
  2671 
  2672 * Simplified interface for defining document antiquotations via
  2673 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2674 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2675 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2676 examples.
  2677 
  2678 * More systematic treatment of long names, abstract name bindings, and
  2679 name space operations.  Basic operations on qualified names have been
  2680 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2681 Long_Name.append.  Old type bstring has been mostly replaced by
  2682 abstract type binding (see structure Binding), which supports precise
  2683 qualification by packages and local theory targets, as well as proper
  2684 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2685 bstring values into Binding.name, or better pass through abstract
  2686 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2687 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2688 
  2689 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2690 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2691 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2692 
  2693 * Disposed old type and term read functions (Sign.read_def_typ,
  2694 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2695 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2696 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2697 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2698 resort for legacy applications.
  2699 
  2700 * Disposed old declarations, tactics, tactic combinators that refer to
  2701 the simpset or claset of an implicit theory (such as Addsimps,
  2702 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2703 embedded ML text, or local_simpset_of with a proper context passed as
  2704 explicit runtime argument.
  2705 
  2706 * Rules and tactics that read instantiations (read_instantiate,
  2707 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2708 context, which is required for parsing and type-checking.  Moreover,
  2709 the variables are specified as plain indexnames, not string encodings
  2710 thereof.  INCOMPATIBILITY.
  2711 
  2712 * Generic Toplevel.add_hook interface allows to analyze the result of
  2713 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2714 for theorem dependency output of transactions resulting in a new
  2715 theory state.
  2716 
  2717 * ML antiquotations: block-structured compilation context indicated by
  2718 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2719 
  2720   @{binding name}                         - basic name binding
  2721   @{let ?pat = term}                      - term abbreviation (HO matching)
  2722   @{note name = fact}                     - fact abbreviation
  2723   @{thm fact}                             - singleton fact (with attributes)
  2724   @{thms fact}                            - general fact (with attributes)
  2725   @{lemma prop by method}                 - singleton goal
  2726   @{lemma prop by meth1 meth2}            - singleton goal
  2727   @{lemma prop1 ... propN by method}      - general goal
  2728   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2729   @{lemma (open) ...}                     - open derivation
  2730 
  2731 
  2732 *** System ***
  2733 
  2734 * The Isabelle "emacs" tool provides a specific interface to invoke
  2735 Proof General / Emacs, with more explicit failure if that is not
  2736 installed (the old isabelle-interface script silently falls back on
  2737 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2738 installation location of the Proof General distribution.
  2739 
  2740 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2741 the Isabelle process into a JVM/Scala application.  See
  2742 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2743 process wrapper has been discontinued.)
  2744 
  2745 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2746 
  2747 * Various status messages (with exact source position information) are
  2748 emitted, if proper markup print mode is enabled.  This allows
  2749 user-interface components to provide detailed feedback on internal
  2750 prover operations.
  2751 
  2752 
  2753 
  2754 New in Isabelle2008 (June 2008)
  2755 -------------------------------
  2756 
  2757 *** General ***
  2758 
  2759 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2760 and updated, with formally checked references as hyperlinks.
  2761 
  2762 * Theory loader: use_thy (and similar operations) no longer set the
  2763 implicit ML context, which was occasionally hard to predict and in
  2764 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2765 provides a proper context already.
  2766 
  2767 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2768 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2769 'use' within a theory file will do the job.
  2770 
  2771 * Name space merge now observes canonical order, i.e. the second space
  2772 is inserted into the first one, while existing entries in the first
  2773 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2774 swap theory imports.
  2775 
  2776 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2777 INCOMPATIBILITY in identifier syntax etc.
  2778 
  2779 * Outer syntax: string tokens no longer admit escaped white space,
  2780 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2781 white space without escapes.
  2782 
  2783 * Outer syntax: string tokens may contain arbitrary character codes
  2784 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2785 "foo_bar".
  2786 
  2787 
  2788 *** Pure ***
  2789 
  2790 * Context-dependent token translations.  Default setup reverts locally
  2791 fixed variables, and adds hilite markup for undeclared frees.
  2792 
  2793 * Unused theorems can be found using the new command 'unused_thms'.
  2794 There are three ways of invoking it:
  2795 
  2796 (1) unused_thms
  2797      Only finds unused theorems in the current theory.
  2798 
  2799 (2) unused_thms thy_1 ... thy_n -
  2800      Finds unused theorems in the current theory and all of its ancestors,
  2801      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2802 
  2803 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2804      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2805      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2806      their ancestors.
  2807 
  2808 In order to increase the readability of the list produced by
  2809 unused_thms, theorems that have been created by a particular instance
  2810 of a theory command such as 'inductive' or 'function' are considered
  2811 to belong to the same "group", meaning that if at least one theorem in
  2812 this group is used, the other theorems in the same group are no longer
  2813 reported as unused.  Moreover, if all theorems in the group are
  2814 unused, only one theorem in the group is displayed.
  2815 
  2816 Note that proof objects have to be switched on in order for
  2817 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2818 usually the case when using Proof General with the default settings).
  2819 
  2820 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2821 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2822 duplicate fact bindings, or even accidental fact duplications.  Note
  2823 that tools may maintain dynamically scoped facts systematically, using
  2824 PureThy.add_thms_dynamic.
  2825 
  2826 * Command 'hide' now allows to hide from "fact" name space as well.
  2827 
  2828 * Eliminated destructive theorem database, simpset, claset, and
  2829 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2830 update of theories within ML code.
  2831 
  2832 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2833 INCOMPATIBILITY, object-logics depending on former Pure require
  2834 additional setup PureThy.old_appl_syntax_setup; object-logics
  2835 depending on former CPure need to refer to Pure.
  2836 
  2837 * Commands 'use' and 'ML' are now purely functional, operating on
  2838 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2839 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2840 INCOMPATIBILITY.
  2841 
  2842 * Command 'setup': discontinued implicit version with ML reference.
  2843 
  2844 * Instantiation target allows for simultaneous specification of class
  2845 instance operations together with an instantiation proof.
  2846 Type-checking phase allows to refer to class operations uniformly.
  2847 See src/HOL/Complex/Complex.thy for an Isar example and
  2848 src/HOL/Library/Eval.thy for an ML example.
  2849 
  2850 * Indexing of literal facts: be more serious about including only
  2851 facts from the visible specification/proof context, but not the
  2852 background context (locale etc.).  Affects `prop` notation and method
  2853 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2854 situations.
  2855 
  2856 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2857 "(open)" option, which used to expose internal bound variables to the
  2858 proof text.
  2859 
  2860 * Isar statements: removed obsolete case "rule_context".
  2861 INCOMPATIBILITY, better use explicit fixes/assumes.
  2862 
  2863 * Locale proofs: default proof step now includes 'unfold_locales';
  2864 hence 'proof' without argument may be used to unfold locale
  2865 predicates.
  2866 
  2867 
  2868 *** Document preparation ***
  2869 
  2870 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2871 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2872 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2873 spot); renamed link color from "darkblue" to "linkcolor" (default
  2874 value unchanged, can be redefined via \definecolor); no longer sets
  2875 "a4paper" option (unnecessary or even intrusive).
  2876 
  2877 * Antiquotation @{lemma A method} proves proposition A by the given
  2878 method (either a method name or a method name plus (optional) method
  2879 arguments in parentheses) and prints A just like @{prop A}.
  2880 
  2881 
  2882 *** HOL ***
  2883 
  2884 * New primrec package.  Specification syntax conforms in style to
  2885 definition/function/....  No separate induction rule is provided.  The
  2886 "primrec" command distinguishes old-style and new-style specifications
  2887 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2888 When adjusting theories, beware: constants stemming from new-style
  2889 primrec specifications have authentic syntax.
  2890 
  2891 * Metis prover is now an order of magnitude faster, and also works
  2892 with multithreading.
  2893 
  2894 * Metis: the maximum number of clauses that can be produced from a
  2895 theorem is now given by the attribute max_clauses.  Theorems that
  2896 exceed this number are ignored, with a warning printed.
  2897 
  2898 * Sledgehammer no longer produces structured proofs by default. To
  2899 enable, declare [[sledgehammer_full = true]].  Attributes
  2900 reconstruction_modulus, reconstruction_sorts renamed
  2901 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2902 
  2903 * Method "induct_scheme" derives user-specified induction rules
  2904 from well-founded induction and completeness of patterns. This factors
  2905 out some operations that are done internally by the function package
  2906 and makes them available separately.  See
  2907 src/HOL/ex/Induction_Scheme.thy for examples.
  2908 
  2909 * More flexible generation of measure functions for termination
  2910 proofs: Measure functions can be declared by proving a rule of the
  2911 form "is_measure f" and giving it the [measure_function] attribute.
  2912 The "is_measure" predicate is logically meaningless (always true), and
  2913 just guides the heuristic.  To find suitable measure functions, the
  2914 termination prover sets up the goal "is_measure ?f" of the appropriate
  2915 type and generates all solutions by prolog-style backwards proof using
  2916 the declared rules.
  2917 
  2918 This setup also deals with rules like 
  2919 
  2920   "is_measure f ==> is_measure (list_size f)"
  2921 
  2922 which accommodates nested datatypes that recurse through lists.
  2923 Similar rules are predeclared for products and option types.
  2924 
  2925 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2926 
  2927   INCOMPATIBILITIES:
  2928 
  2929   - Definitions of overloaded constants on sets have to be replaced by
  2930     definitions on => and bool.
  2931 
  2932   - Some definitions of overloaded operators on sets can now be proved
  2933     using the definitions of the operators on => and bool.  Therefore,
  2934     the following theorems have been renamed:
  2935 
  2936       subset_def   -> subset_eq
  2937       psubset_def  -> psubset_eq
  2938       set_diff_def -> set_diff_eq
  2939       Compl_def    -> Compl_eq
  2940       Sup_set_def  -> Sup_set_eq
  2941       Inf_set_def  -> Inf_set_eq
  2942       sup_set_def  -> sup_set_eq
  2943       inf_set_def  -> inf_set_eq
  2944 
  2945   - Due to the incompleteness of the HO unification algorithm, some
  2946     rules such as subst may require manual instantiation, if some of
  2947     the unknowns in the rule is a set.
  2948 
  2949   - Higher order unification and forward proofs:
  2950     The proof pattern
  2951 
  2952       have "P (S::'a set)" <...>
  2953       then have "EX S. P S" ..
  2954 
  2955     no longer works (due to the incompleteness of the HO unification
  2956     algorithm) and must be replaced by the pattern
  2957 
  2958       have "EX S. P S"
  2959       proof
  2960         show "P S" <...>
  2961       qed
  2962 
  2963   - Calculational reasoning with subst (or similar rules):
  2964     The proof pattern
  2965 
  2966       have "P (S::'a set)" <...>
  2967       also have "S = T" <...>
  2968       finally have "P T" .
  2969 
  2970     no longer works (for similar reasons as the previous example) and
  2971     must be replaced by something like
  2972 
  2973       have "P (S::'a set)" <...>
  2974       moreover have "S = T" <...>
  2975       ultimately have "P T" by simp
  2976 
  2977   - Tactics or packages written in ML code:
  2978     Code performing pattern matching on types via
  2979 
  2980       Type ("set", [T]) => ...
  2981 
  2982     must be rewritten. Moreover, functions like strip_type or
  2983     binder_types no longer return the right value when applied to a
  2984     type of the form
  2985 
  2986       T1 => ... => Tn => U => bool
  2987 
  2988     rather than
  2989 
  2990       T1 => ... => Tn => U set
  2991 
  2992 * Merged theories Wellfounded_Recursion, Accessible_Part and
  2993 Wellfounded_Relations to theory Wellfounded.
  2994 
  2995 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  2996 
  2997 * Class finite no longer treats UNIV as class parameter.  Use class
  2998 enum from theory Library/Enum instead to achieve a similar effect.
  2999 INCOMPATIBILITY.
  3000 
  3001 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  3002 and "Cons".  INCOMPATIBILITY.
  3003 
  3004 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  3005 Potential INCOMPATIBILITY.
  3006 
  3007 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  3008 injective_fst_snd removed, use split_eta and prod_eqI instead.
  3009 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  3010 
  3011 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  3012 the same name in theory Orderings:
  3013 
  3014   less_trans
  3015   less_linear
  3016   le_imp_less_or_eq
  3017   le_less_trans
  3018   less_le_trans
  3019   less_not_sym
  3020   less_asym
  3021 
  3022 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  3023 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  3024 and different variable names.
  3025 
  3026 * Library/Option_ord.thy: Canonical order on option type.
  3027 
  3028 * Library/RBT.thy: Red-black trees, an efficient implementation of
  3029 finite maps.
  3030 
  3031 * Library/Countable.thy: Type class for countable types.
  3032 
  3033 * Theory Int: The representation of numerals has changed.  The infix
  3034 operator BIT and the bit datatype with constructors B0 and B1 have
  3035 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  3036 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  3037 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  3038 accordingly.
  3039 
  3040 * Theory Nat: definition of <= and < on natural numbers no longer
  3041 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  3042 le_def and less_def have disappeared.  Consider lemmas not_less
  3043 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  3044 
  3045 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  3046 (whose purpose mainly is for various fold_set functionals) have been
  3047 abandoned in favor of the existing algebraic classes
  3048 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  3049 lower_semilattice (resp. upper_semilattice) and linorder.
  3050 INCOMPATIBILITY.
  3051 
  3052 * Theory Transitive_Closure: induct and cases rules now declare proper
  3053 case_names ("base" and "step").  INCOMPATIBILITY.
  3054 
  3055 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  3056 lattices.  The form set-specific version is available as
  3057 Inductive.lfp_ordinal_induct_set.
  3058 
  3059 * Renamed theorems "power.simps" to "power_int.simps".
  3060 INCOMPATIBILITY.
  3061 
  3062 * Class semiring_div provides basic abstract properties of semirings
  3063 with division and modulo operations.  Subsumes former class dvd_mod.
  3064 
  3065 * Merged theories IntDef, Numeral and IntArith into unified theory
  3066 Int.  INCOMPATIBILITY.
  3067 
  3068 * Theory Library/Code_Index: type "index" now represents natural
  3069 numbers rather than integers.  INCOMPATIBILITY.
  3070 
  3071 * New class "uminus" with operation "uminus" (split of from class
  3072 "minus" which now only has operation "minus", binary).
  3073 INCOMPATIBILITY.
  3074 
  3075 * Constants "card", "internal_split", "option_map" now with authentic
  3076 syntax.  INCOMPATIBILITY.
  3077 
  3078 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3079 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3080 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3081 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3082 Sup_set_def, le_def, less_def, option_map_def now with object
  3083 equality.  INCOMPATIBILITY.
  3084 
  3085 * Records. Removed K_record, and replaced it by pure lambda term
  3086 %x. c. The simplifier setup is now more robust against eta expansion.
  3087 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3088 
  3089 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3090 
  3091 * Library/ListVector: new theory of arithmetic vector operations.
  3092 
  3093 * Library/Order_Relation: new theory of various orderings as sets of
  3094 pairs.  Defines preorders, partial orders, linear orders and
  3095 well-orders on sets and on types.
  3096 
  3097 
  3098 *** ZF ***
  3099 
  3100 * Renamed some theories to allow to loading both ZF and HOL in the
  3101 same session:
  3102 
  3103   Datatype  -> Datatype_ZF
  3104   Inductive -> Inductive_ZF
  3105   Int       -> Int_ZF
  3106   IntDiv    -> IntDiv_ZF
  3107   Nat       -> Nat_ZF
  3108   List      -> List_ZF
  3109   Main      -> Main_ZF
  3110 
  3111 INCOMPATIBILITY: ZF theories that import individual theories below
  3112 Main might need to be adapted.  Regular theory Main is still
  3113 available, as trivial extension of Main_ZF.
  3114 
  3115 
  3116 *** ML ***
  3117 
  3118 * ML within Isar: antiquotation @{const name} or @{const
  3119 name(typargs)} produces statically-checked Const term.
  3120 
  3121 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3122 (of the same name).  Removed obsolete print command.
  3123 
  3124 * Removed obsolete "use_legacy_bindings" function.
  3125 
  3126 * The ``print mode'' is now a thread-local value derived from a global
  3127 template (the former print_mode reference), thus access becomes
  3128 non-critical.  The global print_mode reference is for session
  3129 management only; user-code should use print_mode_value,
  3130 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3131 
  3132 * Functions system/system_out provide a robust way to invoke external
  3133 shell commands, with propagation of interrupts (requires Poly/ML
  3134 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3135 
  3136 
  3137 *** System ***
  3138 
  3139 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3140 in accordance with Proof General 3.7, which prefers GNU emacs.
  3141 
  3142 * isatool tty runs Isabelle process with plain tty interaction;
  3143 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3144 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3145 
  3146 * isatool browser now works with Cygwin as well, using general
  3147 "javapath" function defined in Isabelle process environment.
  3148 
  3149 * YXML notation provides a simple and efficient alternative to
  3150 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3151 isatool yxml as described in the Isabelle system manual.
  3152 
  3153 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3154 provides general wrapper for managing an Isabelle process in a robust
  3155 fashion, with ``cooked'' output from stdin/stderr.
  3156 
  3157 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3158 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3159 
  3160 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3161 way of changing the user's settings is via
  3162 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3163 script.
  3164 
  3165 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3166 cores of the underlying machine, which is a good starting point for
  3167 optimal performance tuning.  The corresponding usedir option -M allows
  3168 "max" as an alias for "0".  WARNING: does not work on certain versions
  3169 of Mac OS (with Poly/ML 5.1).
  3170 
  3171 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3172 adverse effect of Isabelle flooding interactive front-ends (notably
  3173 ProofGeneral / XEmacs).
  3174 
  3175 
  3176 
  3177 New in Isabelle2007 (November 2007)
  3178 -----------------------------------
  3179 
  3180 *** General ***
  3181 
  3182 * More uniform information about legacy features, notably a
  3183 warning/error of "Legacy feature: ...", depending on the state of the
  3184 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3185 legacy features will disappear eventually.
  3186 
  3187 * Theory syntax: the header format ``theory A = B + C:'' has been
  3188 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3189 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3190 
  3191 * Theory syntax: the old non-Isar theory file format has been
  3192 discontinued altogether.  Note that ML proof scripts may still be used
  3193 with Isar theories; migration is usually quite simple with the ML
  3194 function use_legacy_bindings.  INCOMPATIBILITY.
  3195 
  3196 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3197 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3198 quotes.
  3199 
  3200 * Theory loader: be more serious about observing the static theory
  3201 header specifications (including optional directories), but not the
  3202 accidental file locations of previously successful loads.  The strict
  3203 update policy of former update_thy is now already performed by
  3204 use_thy, so the former has been removed; use_thys updates several
  3205 theories simultaneously, just as 'imports' within a theory header
  3206 specification, but without merging the results.  Potential
  3207 INCOMPATIBILITY: may need to refine theory headers and commands
  3208 ROOT.ML which depend on load order.
  3209 
  3210 * Theory loader: optional support for content-based file
  3211 identification, instead of the traditional scheme of full physical
  3212 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3213 (cf. the system manual).  The new scheme allows to work with
  3214 non-finished theories in persistent session images, such that source
  3215 files may be moved later on without requiring reloads.
  3216 
  3217 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3218 file (with the same base name as the theory) are considered a legacy
  3219 feature, which will disappear eventually. Even now, the theory loader
  3220 no longer maintains dependencies on such files.
  3221 
  3222 * Syntax: the scope for resolving ambiguities via type-inference is
  3223 now limited to individual terms, instead of whole simultaneous
  3224 specifications as before. This greatly reduces the complexity of the
  3225 syntax module and improves flexibility by separating parsing and
  3226 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3227 'fixes' etc.) are required in rare situations.
  3228 
  3229 * Syntax: constants introduced by new-style packages ('definition',
  3230 'abbreviation' etc.) are passed through the syntax module in
  3231 ``authentic mode''. This means that associated mixfix annotations
  3232 really stick to such constants, independently of potential name space
  3233 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3234 trees are represented slightly differently, may need to adapt syntax
  3235 translations accordingly. Use CONST marker in 'translations' and
  3236 @{const_syntax} antiquotation in 'parse_translation' etc.
  3237 
  3238 * Legacy goal package: reduced interface to the bare minimum required
  3239 to keep existing proof scripts running.  Most other user-level
  3240 functions are now part of the OldGoals structure, which is *not* open
  3241 by default (consider isatool expandshort before open OldGoals).
  3242 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3243 these tend to cause confusion about the actual goal (!) context being
  3244 used here, which is not necessarily the same as the_context().
  3245 
  3246 * Command 'find_theorems': supports "*" wild-card in "name:"
  3247 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3248 support a specific search form (see ProofGeneral/CHANGES).
  3249 
  3250 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3251 by default, which means that "prems" (and also "fixed variables") are
  3252 suppressed from proof state output.  Note that the ProofGeneral
  3253 settings mechanism allows to change and save options persistently, but
  3254 older versions of Isabelle will fail to start up if a negative prems
  3255 limit is imposed.
  3256 
  3257 * Local theory targets may be specified by non-nested blocks of
  3258 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3259 contain definitions, theorems etc., including any derived mechanism
  3260 that has been implemented on top of these primitives.  This concept
  3261 generalizes the existing ``theorem (in ...)'' towards more versatility
  3262 and scalability.
  3263 
  3264 * Proof General interface: proper undo of final 'end' command;
  3265 discontinued Isabelle/classic mode (ML proof scripts).
  3266 
  3267 
  3268 *** Document preparation ***
  3269 
  3270 * Added antiquotation @{theory name} which prints the given name,
  3271 after checking that it refers to a valid ancestor theory in the
  3272 current context.
  3273 
  3274 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3275 check the given source text as ML type/structure, printing verbatim.
  3276 
  3277 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3278 "c args == rhs" given in the current context.  (Any number of
  3279 arguments may be given on the LHS.)
  3280 
  3281 
  3282 *** Pure ***
  3283 
  3284 * The 'class' package offers a combination of axclass and locale to
  3285 achieve Haskell-like type classes in Isabelle.  Definitions and
  3286 theorems within a class context produce both relative results (with
  3287 implicit parameters according to the locale context), and polymorphic
  3288 constants with qualified polymorphism (according to the class
  3289 context).  Within the body context of a 'class' target, a separate
  3290 syntax layer ("user space type system") takes care of converting
  3291 between global polymorphic consts and internal locale representation.
  3292 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3293 "isatool doc classes" provides a tutorial.
  3294 
  3295 * Generic code generator framework allows to generate executable
  3296 code for ML and Haskell (including Isabelle classes).  A short usage
  3297 sketch:
  3298 
  3299     internal compilation:
  3300         export_code <list of constants (term syntax)> in SML
  3301     writing SML code to a file:
  3302         export_code <list of constants (term syntax)> in SML <filename>
  3303     writing OCaml code to a file:
  3304         export_code <list of constants (term syntax)> in OCaml <filename>
  3305     writing Haskell code to a bunch of files:
  3306         export_code <list of constants (term syntax)> in Haskell <filename>
  3307 
  3308     evaluating closed propositions to True/False using code generation:
  3309         method ``eval''
  3310 
  3311 Reasonable default setup of framework in HOL.
  3312 
  3313 Theorem attributs for selecting and transforming function equations theorems:
  3314 
  3315     [code fun]:        select a theorem as function equation for a specific constant
  3316     [code fun del]:    deselect a theorem as function equation for a specific constant
  3317     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3318     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3319 
  3320 User-defined serializations (target in {SML, OCaml, Haskell}):
  3321 
  3322     code_const <and-list of constants (term syntax)>
  3323       {(target) <and-list of const target syntax>}+
  3324 
  3325     code_type <and-list of type constructors>
  3326       {(target) <and-list of type target syntax>}+
  3327 
  3328     code_instance <and-list of instances>
  3329       {(target)}+
  3330         where instance ::= <type constructor> :: <class>
  3331 
  3332     code_class <and_list of classes>
  3333       {(target) <and-list of class target syntax>}+
  3334         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3335 
  3336 code_instance and code_class only are effective to target Haskell.
  3337 
  3338 For example usage see src/HOL/ex/Codegenerator.thy and
  3339 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3340 generation from Isabelle/HOL theories is available via "isatool doc
  3341 codegen".
  3342 
  3343 * Code generator: consts in 'consts_code' Isar commands are now
  3344 referred to by usual term syntax (including optional type
  3345 annotations).
  3346 
  3347 * Command 'no_translations' removes translation rules from theory
  3348 syntax.
  3349 
  3350 * Overloaded definitions are now actually checked for acyclic
  3351 dependencies.  The overloading scheme is slightly more general than
  3352 that of Haskell98, although Isabelle does not demand an exact
  3353 correspondence to type class and instance declarations.
  3354 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3355 exotic versions of overloading -- at the discretion of the user!
  3356 
  3357 Polymorphic constants are represented via type arguments, i.e. the
  3358 instantiation that matches an instance against the most general
  3359 declaration given in the signature.  For example, with the declaration
  3360 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3361 as c(nat).  Overloading is essentially simultaneous structural
  3362 recursion over such type arguments.  Incomplete specification patterns
  3363 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3364 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3365 Command 'print_theory' outputs the normalized system of recursive
  3366 equations, see section "definitions".
  3367 
  3368 * Configuration options are maintained within the theory or proof
  3369 context (with name and type bool/int/string), providing a very simple
  3370 interface to a poor-man's version of general context data.  Tools may
  3371 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3372 these values using Config.get etc.  Users may change options via an
  3373 associated attribute of the same name.  This form of context
  3374 declaration works particularly well with commands 'declare' or
  3375 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3376 very easy to avoid global references, which would not observe Isar
  3377 toplevel undo/redo and fail to work with multithreading.
  3378 
  3379 Various global ML references of Pure and HOL have been turned into
  3380 configuration options:
  3381 
  3382   Unify.search_bound		unify_search_bound
  3383   Unify.trace_bound		unify_trace_bound
  3384   Unify.trace_simp		unify_trace_simp
  3385   Unify.trace_types		unify_trace_types
  3386   Simplifier.simp_depth_limit	simp_depth_limit
  3387   Blast.depth_limit		blast_depth_limit
  3388   DatatypeProp.dtK		datatype_distinctness_limit
  3389   fast_arith_neq_limit  	fast_arith_neq_limit
  3390   fast_arith_split_limit	fast_arith_split_limit
  3391 
  3392 * Named collections of theorems may be easily installed as context
  3393 data using the functor NamedThmsFun (see also
  3394 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3395 attributes; there is also a toplevel print command.  This facility is
  3396 just a common case of general context data, which is the preferred way
  3397 for anything more complex than just a list of facts in canonical
  3398 order.
  3399 
  3400 * Isar: command 'declaration' augments a local theory by generic
  3401 declaration functions written in ML.  This enables arbitrary content
  3402 being added to the context, depending on a morphism that tells the
  3403 difference of the original declaration context wrt. the application
  3404 context encountered later on.
  3405 
  3406 * Isar: proper interfaces for simplification procedures.  Command
  3407 'simproc_setup' declares named simprocs (with match patterns, and body
  3408 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3409 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3410 
  3411 * Isar: an extra pair of brackets around attribute declarations
  3412 abbreviates a theorem reference involving an internal dummy fact,
  3413 which will be ignored later --- only the effect of the attribute on
  3414 the background context will persist.  This form of in-place
  3415 declarations is particularly useful with commands like 'declare' and
  3416 'using', for example ``have A using [[simproc a]] by simp''.
  3417 
  3418 * Isar: method "assumption" (and implicit closing of subproofs) now
  3419 takes simple non-atomic goal assumptions into account: after applying
  3420 an assumption as a rule the resulting subgoals are solved by atomic
  3421 assumption steps.  This is particularly useful to finish 'obtain'
  3422 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3423 without referring to the original premise "!!x. P x ==> thesis" in the
  3424 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3425 more permissive.
  3426 
  3427 * Isar: implicit use of prems from the Isar proof context is
  3428 considered a legacy feature.  Common applications like ``have A .''
  3429 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3430 referencing facts explicitly here improves readability and
  3431 maintainability of proof texts.
  3432 
  3433 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3434 the obtained context from the course of reasoning!  For example:
  3435 
  3436   assume "EX x y. A x & B y"   -- "any previous fact"
  3437   then guess x and y by clarify
  3438 
  3439 This technique is potentially adventurous, depending on the facts and
  3440 proof tools being involved here.
  3441 
  3442 * Isar: known facts from the proof context may be specified as literal
  3443 propositions, using ASCII back-quote syntax.  This works wherever
  3444 named facts used to be allowed so far, in proof commands, proof
  3445 methods, attributes etc.  Literal facts are retrieved from the context
  3446 according to unification of type and term parameters.  For example,
  3447 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3448 theorems in the current context, then these are valid literal facts:
  3449 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3450 
  3451 There is also a proof method "fact" which does the same composition
  3452 for explicit goal states, e.g. the following proof texts coincide with
  3453 certain special cases of literal facts:
  3454 
  3455   have "A" by fact                 ==  note `A`
  3456   have "A ==> B" by fact           ==  note `A ==> B`
  3457   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3458   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3459 
  3460 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3461 outer syntax.  Thus symbolic identifiers may be used without
  3462 additional white space in declarations like this: ``assume *: A''.
  3463 
  3464 * Isar: 'print_facts' prints all local facts of the current context,
  3465 both named and unnamed ones.
  3466 
  3467 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3468 
  3469   def x == "t" and y == "u"
  3470 
  3471 * Isar: added command 'unfolding', which is structurally similar to
  3472 'using', but affects both the goal state and facts by unfolding given
  3473 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3474 'unfolded' attribute may be replaced by first-class proof text.
  3475 
  3476 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3477 and command 'unfolding' now all support object-level equalities
  3478 (potentially conditional).  The underlying notion of rewrite rule is
  3479 analogous to the 'rule_format' attribute, but *not* that of the
  3480 Simplifier (which is usually more generous).
  3481 
  3482 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3483 premises of a theorem by n. Useful in conjunction with drule.
  3484 
  3485 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3486 method expression within a sandbox consisting of the first N
  3487 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3488 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3489 simplifies all new goals that emerge from applying rule foo to the
  3490 originally first one.
  3491 
  3492 * Isar: schematic goals are no longer restricted to higher-order
  3493 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3494 expected.
  3495 
  3496 * Isar: the conclusion of a long theorem statement is now either
  3497 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3498 (essentially a disjunction of cases with local parameters and
  3499 assumptions).  The latter allows to express general elimination rules
  3500 adequately; in this notation common elimination rules look like this:
  3501 
  3502   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3503     assumes "EX x. P x"
  3504     obtains x where "P x"
  3505 
  3506   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3507     assumes "A & B"
  3508     obtains A and B
  3509 
  3510   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3511     assumes "A | B"
  3512     obtains
  3513       A
  3514     | B
  3515 
  3516 The subsequent classical rules even refer to the formal "thesis"
  3517 explicitly:
  3518 
  3519   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3520     obtains "~ thesis"
  3521 
  3522   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3523     obtains "thesis ==> something"
  3524 
  3525 The actual proof of an 'obtains' statement is analogous to that of the
  3526 Isar proof element 'obtain', only that there may be several cases.
  3527 Optional case names may be specified in parentheses; these will be
  3528 available both in the present proof and as annotations in the
  3529 resulting rule, for later use with the 'cases' method (cf. attribute
  3530 case_names).
  3531 
  3532 * Isar: the assumptions of a long theorem statement are available as
  3533 "assms" fact in the proof context.  This is more appropriate than the
  3534 (historical) "prems", which refers to all assumptions of the current
  3535 context, including those from the target locale, proof body etc.
  3536 
  3537 * Isar: 'print_statement' prints theorems from the current theory or
  3538 proof context in long statement form, according to the syntax of a
  3539 top-level lemma.
  3540 
  3541 * Isar: 'obtain' takes an optional case name for the local context
  3542 introduction rule (default "that").
  3543 
  3544 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3545 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3546 to occur.
  3547 
  3548 * Pure: syntax "CONST name" produces a fully internalized constant
  3549 according to the current context.  This is particularly useful for
  3550 syntax translations that should refer to internal constant
  3551 representations independently of name spaces.
  3552 
  3553 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3554 instead of "FOO ". This allows multiple binder declarations to coexist
  3555 in the same context.  INCOMPATIBILITY.
  3556 
  3557 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3558 primitive that also works in a locale context (both for constants and
  3559 fixed variables). Type declaration and internal syntactic representation
  3560 of given constants retrieved from the context. Likewise, the
  3561 'no_notation' command allows to remove given syntax annotations from the
  3562 current context.
  3563 
  3564 * Isar/locales: new derived specification elements 'axiomatization',
  3565 'definition', 'abbreviation', which support type-inference, admit
  3566 object-level specifications (equality, equivalence).  See also the
  3567 isar-ref manual.  Examples:
  3568 
  3569   axiomatization
  3570     eq  (infix "===" 50) where
  3571     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3572 
  3573   definition "f x y = x + y + 1"
  3574   definition g where "g x = f x x"
  3575 
  3576   abbreviation
  3577     neq  (infix "=!=" 50) where
  3578     "x =!= y == ~ (x === y)"
  3579 
  3580 These specifications may be also used in a locale context.  Then the
  3581 constants being introduced depend on certain fixed parameters, and the
  3582 constant name is qualified by the locale base name.  An internal
  3583 abbreviation takes care for convenient input and output, making the
  3584 parameters implicit and using the original short name.  See also
  3585 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3586 entities from a monomorphic theory.
  3587 
  3588 Presently, abbreviations are only available 'in' a target locale, but
  3589 not inherited by general import expressions.  Also note that
  3590 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3591 'translations' in common applications.  The "no_abbrevs" print mode
  3592 prevents folding of abbreviations in term output.
  3593 
  3594 Concrete syntax is attached to specified constants in internal form,
  3595 independently of name spaces.  The parse tree representation is
  3596 slightly different -- use 'notation' instead of raw 'syntax', and
  3597 'translations' with explicit "CONST" markup to accommodate this.
  3598 
  3599 * Pure/Isar: unified syntax for new-style specification mechanisms
  3600 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3601 full type inference and dummy patterns ("_").  For example:
  3602 
  3603   definition "K x _ = x"
  3604 
  3605   inductive conj for A B
  3606   where "A ==> B ==> conj A B"
  3607 
  3608 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3609 the current context.  Print mode "no_abbrevs" prevents inversion of
  3610 abbreviations on output.
  3611 
  3612 * Isar/locales: improved parameter handling: use of locales "var" and
  3613 "struct" no longer necessary; - parameter renamings are no longer
  3614 required to be injective.  For example, this allows to define
  3615 endomorphisms as locale endom = homom mult mult h.
  3616 
  3617 * Isar/locales: changed the way locales with predicates are defined.
  3618 Instead of accumulating the specification, the imported expression is
  3619 now an interpretation.  INCOMPATIBILITY: different normal form of
  3620 locale expressions.  In particular, in interpretations of locales with
  3621 predicates, goals repesenting already interpreted fragments are not
  3622 removed automatically.  Use methods `intro_locales' and
  3623 `unfold_locales'; see below.
  3624 
  3625 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3626 provide backward reasoning on locales predicates.  The methods are
  3627 aware of interpretations and discharge corresponding goals.
  3628 `intro_locales' is less aggressive then `unfold_locales' and does not
  3629 unfold predicates to assumptions.
  3630 
  3631 * Isar/locales: the order in which locale fragments are accumulated
  3632 has changed.  This enables to override declarations from fragments due
  3633 to interpretations -- for example, unwanted simp rules.
  3634 
  3635 * Isar/locales: interpretation in theories and proof contexts has been
  3636 extended.  One may now specify (and prove) equations, which are
  3637 unfolded in interpreted theorems.  This is useful for replacing
  3638 defined concepts (constants depending on locale parameters) by
  3639 concepts already existing in the target context.  Example:
  3640 
  3641   interpretation partial_order ["op <= :: [int, int] => bool"]
  3642     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3643 
  3644 Typically, the constant `partial_order.less' is created by a
  3645 definition specification element in the context of locale
  3646 partial_order.
  3647 
  3648 * Method "induct": improved internal context management to support
  3649 local fixes and defines on-the-fly. Thus explicit meta-level
  3650 connectives !!  and ==> are rarely required anymore in inductive goals
  3651 (using object-logic connectives for this purpose has been long
  3652 obsolete anyway). Common proof patterns are explained in
  3653 src/HOL/Induct/Common_Patterns.thy, see also
  3654 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3655 examples.
  3656 
  3657 * Method "induct": improved handling of simultaneous goals. Instead of
  3658 introducing object-level conjunction, the statement is now split into
  3659 several conclusions, while the corresponding symbolic cases are nested
  3660 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3661 see src/HOL/Induct/Common_Patterns.thy, for example.
  3662 
  3663 * Method "induct": mutual induction rules are now specified as a list
  3664 of rule sharing the same induction cases. HOL packages usually provide
  3665 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3666 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3667 mutual induction rules differently, i.e. like this:
  3668 
  3669   (induct rule: foo_bar.inducts)
  3670   (induct set: foo bar)
  3671   (induct pred: foo bar)
  3672   (induct type: foo bar)
  3673 
  3674 The ML function ProjectRule.projections turns old-style rules into the
  3675 new format.
  3676 
  3677 * Method "coinduct": dual of induction, see
  3678 src/HOL/Library/Coinductive_List.thy for various examples.
  3679 
  3680 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3681 considered a legacy feature.
  3682 
  3683 * Attribute "symmetric" produces result with standardized schematic
  3684 variables (index 0).  Potential INCOMPATIBILITY.
  3685 
  3686 * Simplifier: by default the simplifier trace only shows top level
  3687 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3688 default. Thus there is less danger of being flooded by the trace. The
  3689 trace indicates where parts have been suppressed.
  3690   
  3691 * Provers/classical: removed obsolete classical version of elim_format
  3692 attribute; classical elim/dest rules are now treated uniformly when
  3693 manipulating the claset.
  3694 
  3695 * Provers/classical: stricter checks to ensure that supplied intro,
  3696 dest and elim rules are well-formed; dest and elim rules must have at
  3697 least one premise.
  3698 
  3699 * Provers/classical: attributes dest/elim/intro take an optional
  3700 weight argument for the rule (just as the Pure versions).  Weights are
  3701 ignored by automated tools, but determine the search order of single
  3702 rule steps.
  3703 
  3704 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3705 where the body does not mention the bound variable.  Note that dummy
  3706 patterns implicitly depend on their context of bounds, which makes
  3707 "{_. _}" match any set comprehension as expected.  Potential
  3708 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3709 constant "_idtdummy" in the binding position.
  3710 
  3711 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3712 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3713 for example "A -> B" => "Pi A (%_. B)".
  3714 
  3715 * Pure: 'class_deps' command visualizes the subclass relation, using
  3716 the graph browser tool.
  3717 
  3718 * Pure: 'print_theory' now suppresses certain internal declarations by
  3719 default; use '!' option for full details.
  3720 
  3721 
  3722 *** HOL ***
  3723 
  3724 * Method "metis" proves goals by applying the Metis general-purpose
  3725 resolution prover (see also http://gilith.com/software/metis/).
  3726 Examples are in the directory MetisExamples.  WARNING: the
  3727 Isabelle/HOL-Metis integration does not yet work properly with
  3728 multi-threading.
  3729   
  3730 * Command 'sledgehammer' invokes external automatic theorem provers as
  3731 background processes.  It generates calls to the "metis" method if
  3732 successful. These can be pasted into the proof.  Users do not have to
  3733 wait for the automatic provers to return.  WARNING: does not really
  3734 work with multi-threading.
  3735 
  3736 * New "auto_quickcheck" feature tests outermost goal statements for
  3737 potential counter-examples.  Controlled by ML references
  3738 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3739 5000 milliseconds).  Fails silently if statements is outside of
  3740 executable fragment, or any other codgenerator problem occurs.
  3741 
  3742 * New constant "undefined" with axiom "undefined x = undefined".
  3743 
  3744 * Added class "HOL.eq", allowing for code generation with polymorphic
  3745 equality.
  3746 
  3747 * Some renaming of class constants due to canonical name prefixing in
  3748 the new 'class' package:
  3749 
  3750     HOL.abs ~> HOL.abs_class.abs
  3751     HOL.divide ~> HOL.divide_class.divide
  3752     0 ~> HOL.zero_class.zero
  3753     1 ~> HOL.one_class.one
  3754     op + ~> HOL.plus_class.plus
  3755     op - ~> HOL.minus_class.minus
  3756     uminus ~> HOL.minus_class.uminus
  3757     op * ~> HOL.times_class.times
  3758     op < ~> HOL.ord_class.less
  3759     op <= > HOL.ord_class.less_eq
  3760     Nat.power ~> Power.power_class.power
  3761     Nat.size ~> Nat.size_class.size
  3762     Numeral.number_of ~> Numeral.number_class.number_of
  3763     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3764     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3765     Orderings.min ~> Orderings.ord_class.min
  3766     Orderings.max ~> Orderings.ord_class.max
  3767     Divides.op div ~> Divides.div_class.div
  3768     Divides.op mod ~> Divides.div_class.mod
  3769     Divides.op dvd ~> Divides.div_class.dvd
  3770 
  3771 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3772 
  3773 a) User-defined constants using any of the names "plus", "minus",
  3774 "times", "less" or "less_eq". The standard syntax translations for
  3775 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3776 names.
  3777 
  3778 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3779 INCOMPATIBILITY: use more specific names.
  3780 
  3781 c) Permutative equations (e.g. "a + b = b + a")
  3782 Since the change of names also changes the order of terms, permutative
  3783 rewrite rules may get applied in a different order. Experience shows
  3784 that this is rarely the case (only two adaptions in the whole Isabelle
  3785 distribution).  INCOMPATIBILITY: rewrite proofs
  3786 
  3787 d) ML code directly refering to constant names
  3788 This in general only affects hand-written proof tactics, simprocs and
  3789 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3790 Consider using @{const_name} antiquotation.
  3791 
  3792 * New class "default" with associated constant "default".
  3793 
  3794 * Function "sgn" is now overloaded and available on int, real, complex
  3795 (and other numeric types), using class "sgn".  Two possible defs of
  3796 sgn are given as equational assumptions in the classes sgn_if and
  3797 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3798 INCOMPATIBILITY.
  3799 
  3800 * Locale "partial_order" now unified with class "order" (cf. theory
  3801 Orderings), added parameter "less".  INCOMPATIBILITY.
  3802 
  3803 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3804 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3805 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3806 
  3807 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3808 changed order of proof goals in instance proofs.
  3809 
  3810 * The transitivity reasoner for partial and linear orders is set up
  3811 for classes "order" and "linorder".  Instances of the reasoner are available
  3812 in all contexts importing or interpreting the corresponding locales.
  3813 Method "order" invokes the reasoner separately; the reasoner
  3814 is also integrated with the Simplifier as a solver.  Diagnostic
  3815 command 'print_orders' shows the available instances of the reasoner
  3816 in the current context.
  3817 
  3818 * Localized monotonicity predicate in theory "Orderings"; integrated
  3819 lemmas max_of_mono and min_of_mono with this predicate.
  3820 INCOMPATIBILITY.
  3821 
  3822 * Formulation of theorem "dense" changed slightly due to integration
  3823 with new class dense_linear_order.
  3824 
  3825 * Uniform lattice theory development in HOL.
  3826 
  3827     constants "meet" and "join" now named "inf" and "sup"
  3828     constant "Meet" now named "Inf"
  3829 
  3830     classes "meet_semilorder" and "join_semilorder" now named
  3831       "lower_semilattice" and "upper_semilattice"
  3832     class "lorder" now named "lattice"
  3833     class "comp_lat" now named "complete_lattice"
  3834 
  3835     Instantiation of lattice classes allows explicit definitions
  3836     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3837 
  3838   INCOMPATIBILITY.  Theorem renames:
  3839 
  3840     meet_left_le            ~> inf_le1
  3841     meet_right_le           ~> inf_le2
  3842     join_left_le            ~> sup_ge1
  3843     join_right_le           ~> sup_ge2
  3844     meet_join_le            ~> inf_sup_ord
  3845     le_meetI                ~> le_infI
  3846     join_leI                ~> le_supI
  3847     le_meet                 ~> le_inf_iff
  3848     le_join                 ~> ge_sup_conv
  3849     meet_idempotent         ~> inf_idem
  3850     join_idempotent         ~> sup_idem
  3851     meet_comm               ~> inf_commute
  3852     join_comm               ~> sup_commute
  3853     meet_leI1               ~> le_infI1
  3854     meet_leI2               ~> le_infI2
  3855     le_joinI1               ~> le_supI1
  3856     le_joinI2               ~> le_supI2
  3857     meet_assoc              ~> inf_assoc
  3858     join_assoc              ~> sup_assoc
  3859     meet_left_comm          ~> inf_left_commute
  3860     meet_left_idempotent    ~> inf_left_idem
  3861     join_left_comm          ~> sup_left_commute
  3862     join_left_idempotent    ~> sup_left_idem
  3863     meet_aci                ~> inf_aci
  3864     join_aci                ~> sup_aci
  3865     le_def_meet             ~> le_iff_inf
  3866     le_def_join             ~> le_iff_sup
  3867     join_absorp2            ~> sup_absorb2
  3868     join_absorp1            ~> sup_absorb1
  3869     meet_absorp1            ~> inf_absorb1
  3870     meet_absorp2            ~> inf_absorb2
  3871     meet_join_absorp        ~> inf_sup_absorb
  3872     join_meet_absorp        ~> sup_inf_absorb
  3873     distrib_join_le         ~> distrib_sup_le
  3874     distrib_meet_le         ~> distrib_inf_le
  3875 
  3876     add_meet_distrib_left   ~> add_inf_distrib_left
  3877     add_join_distrib_left   ~> add_sup_distrib_left
  3878     is_join_neg_meet        ~> is_join_neg_inf
  3879     is_meet_neg_join        ~> is_meet_neg_sup
  3880     add_meet_distrib_right  ~> add_inf_distrib_right
  3881     add_join_distrib_right  ~> add_sup_distrib_right
  3882     add_meet_join_distribs  ~> add_sup_inf_distribs
  3883     join_eq_neg_meet        ~> sup_eq_neg_inf
  3884     meet_eq_neg_join        ~> inf_eq_neg_sup
  3885     add_eq_meet_join        ~> add_eq_inf_sup
  3886     meet_0_imp_0            ~> inf_0_imp_0
  3887     join_0_imp_0            ~> sup_0_imp_0
  3888     meet_0_eq_0             ~> inf_0_eq_0
  3889     join_0_eq_0             ~> sup_0_eq_0
  3890     neg_meet_eq_join        ~> neg_inf_eq_sup
  3891     neg_join_eq_meet        ~> neg_sup_eq_inf
  3892     join_eq_if              ~> sup_eq_if
  3893 
  3894     mono_meet               ~> mono_inf
  3895     mono_join               ~> mono_sup
  3896     meet_bool_eq            ~> inf_bool_eq
  3897     join_bool_eq            ~> sup_bool_eq
  3898     meet_fun_eq             ~> inf_fun_eq
  3899     join_fun_eq             ~> sup_fun_eq
  3900     meet_set_eq             ~> inf_set_eq
  3901     join_set_eq             ~> sup_set_eq
  3902     meet1_iff               ~> inf1_iff
  3903     meet2_iff               ~> inf2_iff
  3904     meet1I                  ~> inf1I
  3905     meet2I                  ~> inf2I
  3906     meet1D1                 ~> inf1D1
  3907     meet2D1                 ~> inf2D1
  3908     meet1D2                 ~> inf1D2
  3909     meet2D2                 ~> inf2D2
  3910     meet1E                  ~> inf1E
  3911     meet2E                  ~> inf2E
  3912     join1_iff               ~> sup1_iff
  3913     join2_iff               ~> sup2_iff
  3914     join1I1                 ~> sup1I1
  3915     join2I1                 ~> sup2I1
  3916     join1I1                 ~> sup1I1
  3917     join2I2                 ~> sup1I2
  3918     join1CI                 ~> sup1CI
  3919     join2CI                 ~> sup2CI
  3920     join1E                  ~> sup1E
  3921     join2E                  ~> sup2E
  3922 
  3923     is_meet_Meet            ~> is_meet_Inf
  3924     Meet_bool_def           ~> Inf_bool_def
  3925     Meet_fun_def            ~> Inf_fun_def
  3926     Meet_greatest           ~> Inf_greatest
  3927     Meet_lower              ~> Inf_lower
  3928     Meet_set_def            ~> Inf_set_def
  3929 
  3930     Sup_def                 ~> Sup_Inf
  3931     Sup_bool_eq             ~> Sup_bool_def
  3932     Sup_fun_eq              ~> Sup_fun_def
  3933     Sup_set_eq              ~> Sup_set_def
  3934 
  3935     listsp_meetI            ~> listsp_infI
  3936     listsp_meet_eq          ~> listsp_inf_eq
  3937 
  3938     meet_min                ~> inf_min
  3939     join_max                ~> sup_max
  3940 
  3941 * Added syntactic class "size"; overloaded constant "size" now has
  3942 type "'a::size ==> bool"
  3943 
  3944 * Internal reorganisation of `size' of datatypes: size theorems
  3945 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3946 simplification rules by default!); theorems "prod.size" now named
  3947 "*.size".
  3948 
  3949 * Class "div" now inherits from class "times" rather than "type".
  3950 INCOMPATIBILITY.
  3951 
  3952 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  3953 Linorder etc.  have disappeared; operations defined in terms of
  3954 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  3955 
  3956 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  3957 
  3958 * HOL-Word: New extensive library and type for generic, fixed size
  3959 machine words, with arithemtic, bit-wise, shifting and rotating
  3960 operations, reflection into int, nat, and bool lists, automation for
  3961 linear arithmetic (by automatic reflection into nat or int), including
  3962 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  3963 arithmetic type classes, supporting automatic simplification of
  3964 numerals on all operations.
  3965 
  3966 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  3967 
  3968 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  3969 
  3970 * Code generator library theories:
  3971   - Code_Integer represents HOL integers by big integer literals in target
  3972     languages.
  3973   - Code_Char represents HOL characters by character literals in target
  3974     languages.
  3975   - Code_Char_chr like Code_Char, but also offers treatment of character
  3976     codes; includes Code_Integer.
  3977   - Executable_Set allows to generate code for finite sets using lists.
  3978   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  3979     denominator).
  3980   - Executable_Real implements a subset of real numbers, namly those
  3981     representable by rational numbers.
  3982   - Efficient_Nat implements natural numbers by integers, which in general will
  3983     result in higher efficency; pattern matching with 0/Suc is eliminated;
  3984     includes Code_Integer.
  3985   - Code_Index provides an additional datatype index which is mapped to
  3986     target-language built-in integers.
  3987   - Code_Message provides an additional datatype message_string which is isomorphic to
  3988     strings; messages are mapped to target-language strings.
  3989 
  3990 * New package for inductive predicates
  3991 
  3992   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  3993 
  3994     inductive
  3995       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3996       for z_1 :: U_1 and ... and z_n :: U_m
  3997     where
  3998       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3999     | ...
  4000 
  4001   with full support for type-inference, rather than
  4002 
  4003     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4004 
  4005     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4006     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4007 
  4008     inductive "s z_1 ... z_m"
  4009     intros
  4010       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4011       ...
  4012 
  4013   For backward compatibility, there is a wrapper allowing inductive
  4014   sets to be defined with the new package via
  4015 
  4016     inductive_set
  4017       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4018       for z_1 :: U_1 and ... and z_n :: U_m
  4019     where
  4020       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4021     | ...
  4022 
  4023   or
  4024 
  4025     inductive_set
  4026       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4027       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4028       for z_1 :: U_1 and ... and z_n :: U_m
  4029     where
  4030       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4031     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4032     | ...
  4033 
  4034   if the additional syntax "p ..." is required.
  4035 
  4036   Numerous examples can be found in the subdirectories src/HOL/Auth,
  4037   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  4038 
  4039   INCOMPATIBILITIES:
  4040 
  4041   - Since declaration and definition of inductive sets or predicates
  4042     is no longer separated, abbreviations involving the newly
  4043     introduced sets or predicates must be specified together with the
  4044     introduction rules after the 'where' keyword (see above), rather
  4045     than before the actual inductive definition.
  4046 
  4047   - The variables in induction and elimination rules are now
  4048     quantified in the order of their occurrence in the introduction
  4049     rules, rather than in alphabetical order. Since this may break
  4050     some proofs, these proofs either have to be repaired, e.g. by
  4051     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  4052     statements of the form
  4053 
  4054       case (rule_i a_i_1 ... a_i_{k_i})
  4055 
  4056     or the old order of quantification has to be restored by explicitly adding
  4057     meta-level quantifiers in the introduction rules, i.e.
  4058 
  4059       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  4060 
  4061   - The format of the elimination rules is now
  4062 
  4063       p z_1 ... z_m x_1 ... x_n ==>
  4064         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4065         ==> ... ==> P
  4066 
  4067     for predicates and
  4068 
  4069       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4070         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4071         ==> ... ==> P
  4072 
  4073     for sets rather than
  4074 
  4075       x : s z_1 ... z_m ==>
  4076         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4077         ==> ... ==> P
  4078 
  4079     This may require terms in goals to be expanded to n-tuples
  4080     (e.g. using case_tac or simplification with the split_paired_all
  4081     rule) before the above elimination rule is applicable.
  4082 
  4083   - The elimination or case analysis rules for (mutually) inductive
  4084     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4085     list of rules "p_1_..._p_k.elims" is no longer available.
  4086 
  4087 * New package "function"/"fun" for general recursive functions,
  4088 supporting mutual and nested recursion, definitions in local contexts,
  4089 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4090 for small examples, and the separate tutorial on the function
  4091 package. The old recdef "package" is still available as before, but
  4092 users are encouraged to use the new package.
  4093 
  4094 * Method "lexicographic_order" automatically synthesizes termination
  4095 relations as lexicographic combinations of size measures. 
  4096 
  4097 * Case-expressions allow arbitrary constructor-patterns (including
  4098 "_") and take their order into account, like in functional
  4099 programming.  Internally, this is translated into nested
  4100 case-expressions; missing cases are added and mapped to the predefined
  4101 constant "undefined". In complicated cases printing may no longer show
  4102 the original input but the internal form. Lambda-abstractions allow
  4103 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4104 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4105 variable.
  4106 
  4107 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4108 is an abbreviation for "of_nat :: nat => int". The simplification
  4109 rules for "of_nat" have been changed to work like "int" did
  4110 previously.  Potential INCOMPATIBILITY:
  4111   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4112   - of_nat_diff and of_nat_mult are no longer default simp rules
  4113 
  4114 * Method "algebra" solves polynomial equations over (semi)rings using
  4115 Groebner bases. The (semi)ring structure is defined by locales and the
  4116 tool setup depends on that generic context. Installing the method for
  4117 a specific type involves instantiating the locale and possibly adding
  4118 declarations for computation on the coefficients.  The method is
  4119 already instantiated for natural numbers and for the axiomatic class
  4120 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4121 CALCULEMUS 2007 for the general principles underlying this
  4122 architecture of context-aware proof-tools.
  4123 
  4124 * Method "ferrack" implements quantifier elimination over
  4125 special-purpose dense linear orders using locales (analogous to
  4126 "algebra"). The method is already installed for class
  4127 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4128 rat, etc.
  4129 
  4130 * Former constant "List.op @" now named "List.append".  Use ML
  4131 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4132 circumvent possible incompatibilities when working on ML level.
  4133 
  4134 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4135 
  4136 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4137 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4138 
  4139 * New syntax for Haskell-like list comprehension (input only), eg.
  4140 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4141 
  4142 * The special syntax for function "filter" has changed from [x :
  4143 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4144 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4145 
  4146 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4147 defined on nat only, as an abbreviation for [a..<Suc b]
  4148 INCOMPATIBILITY.
  4149 
  4150 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4151 
  4152 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4153 
  4154 * New lemma collection field_simps (an extension of ring_simps) for
  4155 manipulating (in)equations involving division. Multiplies with all
  4156 denominators that can be proved to be non-zero (in equations) or
  4157 positive/negative (in inequations).
  4158 
  4159 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4160 have been improved and renamed to ring_simps, group_simps and
  4161 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4162 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4163 
  4164 * Theory Library/Commutative_Ring: switched from recdef to function
  4165 package; constants add, mul, pow now curried.  Infix syntax for
  4166 algebraic operations.
  4167 
  4168 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4169 INCOMPATIBILITY.
  4170 
  4171 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4172 INCOMPATIBILITY.
  4173 
  4174 * HOL/records: generalised field-update to take a function on the
  4175 field rather than the new value: r(|A := x|) is translated to A_update
  4176 (K x) r The K-combinator that is internally used is called K_record.
  4177 INCOMPATIBILITY: Usage of the plain update functions has to be
  4178 adapted.
  4179  
  4180 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4181 * x = 0, which are required for a semiring.  Richer structures do not
  4182 inherit from semiring_0 anymore, because this property is a theorem
  4183 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4184 there is more to prove, but this is mostly trivial.
  4185 
  4186 * Class "recpower" is generalized to arbitrary monoids, not just
  4187 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4188 commutativity or semiring properties additionally.
  4189 
  4190 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4191 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4192 better use 'abbreviation'.
  4193 
  4194 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4195 
  4196 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4197 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4198 significant changes for setting up numeral syntax for types:
  4199   - New constants Numeral.pred and Numeral.succ instead
  4200       of former Numeral.bin_pred and Numeral.bin_succ.
  4201   - Use integer operations instead of bin_add, bin_mult and so on.
  4202   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4203   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4204 
  4205 See src/HOL/Integ/IntArith.thy for an example setup.
  4206 
  4207 * Command 'normal_form' computes the normal form of a term that may
  4208 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4209 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4210 heavy-duty computations because the functions are compiled to ML
  4211 first.  Correspondingly, a method "normalization" is provided.  See
  4212 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4213 
  4214 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4215 25 like -->); output depends on the "iff" print_mode, the default is
  4216 "A = B" (with priority 50).
  4217 
  4218 * Relations less (<) and less_eq (<=) are also available on type bool.
  4219 Modified syntax to disallow nesting without explicit parentheses,
  4220 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4221 INCOMPATIBILITY.
  4222 
  4223 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4224 
  4225 * Relation composition operator "op O" now has precedence 75 and binds
  4226 stronger than union and intersection. INCOMPATIBILITY.
  4227 
  4228 * The old set interval syntax "{m..n(}" (and relatives) has been
  4229 removed.  Use "{m..<n}" (and relatives) instead.
  4230 
  4231 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4232 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4233 ``declare [[simproc del: neq]]''.
  4234 
  4235 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4236 True/False.
  4237 
  4238 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4239 
  4240 * Theorem setsum_mult renamed to setsum_right_distrib.
  4241 
  4242 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4243 ``rule'' method.
  4244 
  4245 * Reimplemented methods "sat" and "satx", with several improvements:
  4246 goals no longer need to be stated as "<prems> ==> False", equivalences
  4247 (i.e. "=" on type bool) are handled, variable names of the form
  4248 "lit_<n>" are no longer reserved, significant speedup.
  4249 
  4250 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4251 zChaff is still supported as well.
  4252 
  4253 * 'inductive' and 'datatype': provide projections of mutual rules,
  4254 bundled as foo_bar.inducts;
  4255 
  4256 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4257 Library.
  4258 
  4259 * Library: moved theory Accessible_Part to main HOL.
  4260 
  4261 * Library: added theory Coinductive_List of potentially infinite lists
  4262 as greatest fixed-point.
  4263 
  4264 * Library: added theory AssocList which implements (finite) maps as
  4265 association lists.
  4266 
  4267 * Method "evaluation" solves goals (i.e. a boolean expression)
  4268 efficiently by compiling it to ML.  The goal is "proved" (via an
  4269 oracle) if it evaluates to True.
  4270 
  4271 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4272 also when invoked by the simplifier.  This results in the Simplifier
  4273 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4274 Configuration option fast_arith_split_limit=0 recovers the old
  4275 behavior.
  4276 
  4277 * Support for hex (0x20) and binary (0b1001) numerals.
  4278 
  4279 * New method: reify eqs (t), where eqs are equations for an
  4280 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4281 parameter, computes a term s::'b and a list xs::'a list and proves the
  4282 theorem I xs s = t. This is also known as reification or quoting. The
  4283 resulting theorem is applied to the subgoal to substitute t with I xs
  4284 s.  If t is omitted, the subgoal itself is reified.
  4285 
  4286 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4287 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4288 where f is supposed to be a computable function (in the sense of code
  4289 generattion). The method uses reify to compute s and xs as above then
  4290 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4291 r and finally gets the theorem t = r, which is again applied to the
  4292 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4293 
  4294 * Reflection: Automatic reification now handels binding, an example is
  4295 available in src/HOL/ex/ReflectionEx.thy
  4296 
  4297 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4298 command 'statespace' that is similar to 'record', but introduces an
  4299 abstract specification based on the locale infrastructure instead of
  4300 HOL types.  This leads to extra flexibility in composing state spaces,
  4301 in particular multiple inheritance and renaming of components.
  4302 
  4303 
  4304 *** HOL-Complex ***
  4305 
  4306 * Hyperreal: Functions root and sqrt are now defined on negative real
  4307 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4308 Nonnegativity side conditions have been removed from many lemmas, so
  4309 that more subgoals may now be solved by simplification; potential
  4310 INCOMPATIBILITY.
  4311 
  4312 * Real: new type classes formalize real normed vector spaces and
  4313 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4314 and norm :: 'a => real.
  4315 
  4316 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4317 reals into other types. The overloaded constant Reals :: 'a set is now
  4318 defined as range of_real; potential INCOMPATIBILITY.
  4319 
  4320 * Real: proper support for ML code generation, including 'quickcheck'.
  4321 Reals are implemented as arbitrary precision rationals.
  4322 
  4323 * Hyperreal: Several constants that previously worked only for the
  4324 reals have been generalized, so they now work over arbitrary vector
  4325 spaces. Type annotations may need to be added in some cases; potential
  4326 INCOMPATIBILITY.
  4327 
  4328   Infinitesimal  :: ('a::real_normed_vector) star set
  4329   HFinite        :: ('a::real_normed_vector) star set
  4330   HInfinite      :: ('a::real_normed_vector) star set
  4331   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4332   monad          :: ('a::real_normed_vector) star => 'a star set
  4333   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4334   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4335   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4336   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4337   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4338   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4339   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4340   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4341   sgn            :: 'a::real_normed_vector => 'a
  4342   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4343 
  4344 * Complex: Some complex-specific constants are now abbreviations for
  4345 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4346 hnorm.  Other constants have been entirely removed in favor of the
  4347 polymorphic versions (INCOMPATIBILITY):
  4348 
  4349   approx        <-- capprox
  4350   HFinite       <-- CFinite
  4351   HInfinite     <-- CInfinite
  4352   Infinitesimal <-- CInfinitesimal
  4353   monad         <-- cmonad
  4354   galaxy        <-- cgalaxy
  4355   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4356   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4357   (ns)deriv     <-- (ns)cderiv
  4358 
  4359 
  4360 *** HOL-Algebra ***
  4361 
  4362 * Formalisation of ideals and the quotient construction over rings.
  4363 
  4364 * Order and lattice theory no longer based on records.
  4365 INCOMPATIBILITY.
  4366 
  4367 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4368 greatest_closed.  INCOMPATIBILITY.
  4369 
  4370 * Method algebra is now set up via an attribute.  For examples see
  4371 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4372 of algebraic structures.
  4373 
  4374 * Renamed theory CRing to Ring.
  4375 
  4376 
  4377 *** HOL-Nominal ***
  4378 
  4379 * Substantial, yet incomplete support for nominal datatypes (binding
  4380 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4381 src/HOL/Nominal/Examples.  Prospective users should consult
  4382 http://isabelle.in.tum.de/nominal/
  4383 
  4384 
  4385 *** ML ***
  4386 
  4387 * ML basics: just one true type int, which coincides with IntInf.int
  4388 (even on SML/NJ).
  4389 
  4390 * ML within Isar: antiquotations allow to embed statically-checked
  4391 formal entities in the source, referring to the context available at
  4392 compile-time.  For example:
  4393 
  4394 ML {* @{sort "{zero,one}"} *}
  4395 ML {* @{typ "'a => 'b"} *}
  4396 ML {* @{term "%x. x"} *}
  4397 ML {* @{prop "x == y"} *}
  4398 ML {* @{ctyp "'a => 'b"} *}
  4399 ML {* @{cterm "%x. x"} *}
  4400 ML {* @{cprop "x == y"} *}
  4401 ML {* @{thm asm_rl} *}
  4402 ML {* @{thms asm_rl} *}
  4403 ML {* @{type_name c} *}
  4404 ML {* @{type_syntax c} *}
  4405 ML {* @{const_name c} *}
  4406 ML {* @{const_syntax c} *}
  4407 ML {* @{context} *}
  4408 ML {* @{theory} *}
  4409 ML {* @{theory Pure} *}
  4410 ML {* @{theory_ref} *}
  4411 ML {* @{theory_ref Pure} *}
  4412 ML {* @{simpset} *}
  4413 ML {* @{claset} *}
  4414 ML {* @{clasimpset} *}
  4415 
  4416 The same works for sources being ``used'' within an Isar context.
  4417 
  4418 * ML in Isar: improved error reporting; extra verbosity with
  4419 ML_Context.trace enabled.
  4420 
  4421 * Pure/General/table.ML: the join operations now works via exceptions
  4422 DUP/SAME instead of type option. This is simpler in simple cases, and
  4423 admits slightly more efficient complex applications.
  4424 
  4425 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4426 use Context.generic instead of just theory.
  4427 
  4428 * Pure: datatype Context.generic joins theory/Proof.context and
  4429 provides some facilities for code that works in either kind of
  4430 context, notably GenericDataFun for uniform theory and proof data.
  4431 
  4432 * Pure: simplified internal attribute type, which is now always
  4433 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4434 local (Proof.context) attributes have been discontinued, while
  4435 minimizing code duplication. Thm.rule_attribute and
  4436 Thm.declaration_attribute build canonical attributes; see also structure
  4437 Context for further operations on Context.generic, notably
  4438 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4439 declarations and definitions.
  4440 
  4441 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4442 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4443 init only required for impure data. INCOMPATIBILITY: empty really need
  4444 to be empty (no dependencies on theory content!)
  4445 
  4446 * Pure/kernel: consts certification ignores sort constraints given in
  4447 signature declarations. (This information is not relevant to the
  4448 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4449 potential INCOMPATIBILITY.
  4450 
  4451 * Pure: axiomatic type classes are now purely definitional, with
  4452 explicit proofs of class axioms and super class relations performed
  4453 internally. See Pure/axclass.ML for the main internal interfaces --
  4454 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4455 AxClass.axiomatize_class/classrel/arity supersede
  4456 Sign.add_classes/classrel/arities.
  4457 
  4458 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4459 global/local versions on theory vs. Proof.context have been
  4460 discontinued; Attrib.syntax and Method.syntax have been adapted
  4461 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4462 attributes, methods, etc.
  4463 
  4464 * Pure: several functions of signature "... -> theory -> theory * ..."
  4465 have been reoriented to "... -> theory -> ... * theory" in order to
  4466 allow natural usage in combination with the ||>, ||>>, |-> and
  4467 fold_map combinators.
  4468 
  4469 * Pure: official theorem names (closed derivations) and additional
  4470 comments (tags) are now strictly separate.  Name hints -- which are
  4471 maintained as tags -- may be attached any time without affecting the
  4472 derivation.
  4473 
  4474 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4475 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4476 achieve the old behaviour.
  4477 
  4478 * Pure: the "Goal" constant is now called "prop", supporting a
  4479 slightly more general idea of ``protecting'' meta-level rule
  4480 statements.
  4481 
  4482 * Pure: Logic.(un)varify only works in a global context, which is now
  4483 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4484 Logic.legacy_(un)varify as temporary workaround.
  4485 
  4486 * Pure: structure Name provides scalable operations for generating
  4487 internal variable names, notably Name.variants etc.  This replaces
  4488 some popular functions from term.ML:
  4489 
  4490   Term.variant		->  Name.variant
  4491   Term.variantlist	->  Name.variant_list
  4492   Term.invent_names	->  Name.invent_list
  4493 
  4494 Note that low-level renaming rarely occurs in new code -- operations
  4495 from structure Variable are used instead (see below).
  4496 
  4497 * Pure: structure Variable provides fundamental operations for proper
  4498 treatment of fixed/schematic variables in a context.  For example,
  4499 Variable.import introduces fixes for schematics of given facts and
  4500 Variable.export reverses the effect (up to renaming) -- this replaces
  4501 various freeze_thaw operations.
  4502 
  4503 * Pure: structure Goal provides simple interfaces for
  4504 init/conclude/finish and tactical prove operations (replacing former
  4505 Tactic.prove).  Goal.prove is the canonical way to prove results
  4506 within a given context; Goal.prove_global is a degraded version for
  4507 theory level goals, including a global Drule.standard.  Note that
  4508 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4509 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4510 in a locale context).
  4511 
  4512 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4513 and type checking (Syntax.check_term etc.), with common combinations
  4514 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4515 which are considered legacy and await removal.
  4516 
  4517 * Pure/Syntax: generic interfaces for type unchecking
  4518 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4519 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4520 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4521 available for convenience, but refer to the very same operations using
  4522 a mere theory instead of a full context.
  4523 
  4524 * Isar: simplified treatment of user-level errors, using exception
  4525 ERROR of string uniformly.  Function error now merely raises ERROR,
  4526 without any side effect on output channels.  The Isar toplevel takes
  4527 care of proper display of ERROR exceptions.  ML code may use plain
  4528 handle/can/try; cat_error may be used to concatenate errors like this:
  4529 
  4530   ... handle ERROR msg => cat_error msg "..."
  4531 
  4532 Toplevel ML code (run directly or through the Isar toplevel) may be
  4533 embedded into the Isar toplevel with exception display/debug like
  4534 this:
  4535 
  4536   Isar.toplevel (fn () => ...)
  4537 
  4538 INCOMPATIBILITY, removed special transform_error facilities, removed
  4539 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4540 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4541 -- use plain ERROR instead.
  4542 
  4543 * Isar: theory setup now has type (theory -> theory), instead of a
  4544 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4545 
  4546 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4547 ProofContext.debug/verbose flags.
  4548 
  4549 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4550 theory before entering a proof state.  Transactions now always see a
  4551 quasi-functional intermediate checkpoint, both in interactive and
  4552 batch mode.
  4553 
  4554 * Isar: simplified interfaces for outer syntax.  Renamed
  4555 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4556 OuterSyntax.add_parsers -- this functionality is now included in
  4557 OuterSyntax.command etc.  INCOMPATIBILITY.
  4558 
  4559 * Simplifier: the simpset of a running simplification process now
  4560 contains a proof context (cf. Simplifier.the_context), which is the
  4561 very context that the initial simpset has been retrieved from (by
  4562 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4563 (solver, looper etc.) may depend on arbitrary proof data.
  4564 
  4565 * Simplifier.inherit_context inherits the proof context (plus the
  4566 local bounds) of the current simplification process; any simproc
  4567 etc. that calls the Simplifier recursively should do this!  Removed
  4568 former Simplifier.inherit_bounds, which is already included here --
  4569 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4570 specify an explicit context using Simplifier.context/theory_context.
  4571 
  4572 * Simplifier/Classical Reasoner: more abstract interfaces
  4573 change_simpset/claset for modifying the simpset/claset reference of a
  4574 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4575 INCOMPATIBILITY.
  4576 
  4577 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4578 "Trueprop" etc.
  4579 
  4580 
  4581 *** System ***
  4582 
  4583 * settings: the default heap location within ISABELLE_HOME_USER now
  4584 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4585 Isabelle installations.
  4586 
  4587 * isabelle-process: option -S (secure mode) disables some critical
  4588 operations, notably runtime compilation and evaluation of ML source
  4589 code.
  4590 
  4591 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4592 
  4593 * Support for parallel execution, using native multicore support of
  4594 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4595 independent theories, according to the given theory header
  4596 specifications. The maximum number of worker threads is specified via
  4597 usedir option -M or the "max-threads" setting in Proof General. A
  4598 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4599 to 6 on a 8-core machine.  User-code needs to observe certain
  4600 guidelines for thread-safe programming, see appendix A in the Isar
  4601 Implementation manual.
  4602 
  4603 
  4604 
  4605 New in Isabelle2005 (October 2005)
  4606 ----------------------------------
  4607 
  4608 *** General ***
  4609 
  4610 * Theory headers: the new header syntax for Isar theories is
  4611 
  4612   theory <name>
  4613   imports <theory1> ... <theoryN>
  4614   uses <file1> ... <fileM>
  4615   begin
  4616 
  4617 where the 'uses' part is optional.  The previous syntax
  4618 
  4619   theory <name> = <theory1> + ... + <theoryN>:
  4620 
  4621 will disappear in the next release.  Use isatool fixheaders to convert
  4622 existing theory files.  Note that there is no change in ancient
  4623 non-Isar theories now, but these will disappear soon.
  4624 
  4625 * Theory loader: parent theories can now also be referred to via
  4626 relative and absolute paths.
  4627 
  4628 * Command 'find_theorems' searches for a list of criteria instead of a
  4629 list of constants. Known criteria are: intro, elim, dest, name:string,
  4630 simp:term, and any term. Criteria can be preceded by '-' to select
  4631 theorems that do not match. Intro, elim, dest select theorems that
  4632 match the current goal, name:s selects theorems whose fully qualified
  4633 name contain s, and simp:term selects all simplification rules whose
  4634 lhs match term.  Any other term is interpreted as pattern and selects
  4635 all theorems matching the pattern. Available in ProofGeneral under
  4636 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4637 
  4638   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4639 
  4640 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4641 matching the current goal as introduction rule and not having "HOL."
  4642 in their name (i.e. not being defined in theory HOL).
  4643 
  4644 * Command 'thms_containing' has been discontinued in favour of
  4645 'find_theorems'; INCOMPATIBILITY.
  4646 
  4647 * Communication with Proof General is now 8bit clean, which means that
  4648 Unicode text in UTF-8 encoding may be used within theory texts (both
  4649 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4650 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4651 
  4652   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4653   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4654 
  4655 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4656 Classical Reasoner.  Typical big applications run around 2 times
  4657 faster.
  4658 
  4659 
  4660 *** Document preparation ***
  4661 
  4662 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4663 of raw sources.  Only those symbols that do not require additional
  4664 LaTeX packages (depending on comments in isabellesym.sty) are
  4665 displayed properly, everything else is left verbatim.  isatool display
  4666 and isatool print are used as front ends (these are subject to the
  4667 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4668 
  4669 * Command tags control specific markup of certain regions of text,
  4670 notably folding and hiding.  Predefined tags include "theory" (for
  4671 theory begin and end), "proof" for proof commands, and "ML" for
  4672 commands involving ML code; the additional tags "visible" and
  4673 "invisible" are unused by default.  Users may give explicit tag
  4674 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4675 interpretation of tags is determined by the LaTeX job during document
  4676 preparation: see option -V of isatool usedir, or options -n and -t of
  4677 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4678 \isadroptag.
  4679 
  4680 Several document versions may be produced at the same time via isatool
  4681 usedir (the generated index.html will link all of them).  Typical
  4682 specifications include ''-V document=theory,proof,ML'' to present
  4683 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4684 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4685 these parts without any formal replacement text.  The Isabelle site
  4686 default settings produce ''document'' and ''outline'' versions as
  4687 specified above.
  4688 
  4689 * Several new antiquotations:
  4690 
  4691   @{term_type term} prints a term with its type annotated;
  4692 
  4693   @{typeof term} prints the type of a term;
  4694 
  4695   @{const const} is the same as @{term const}, but checks that the
  4696   argument is a known logical constant;
  4697 
  4698   @{term_style style term} and @{thm_style style thm} print a term or
  4699   theorem applying a "style" to it
  4700 
  4701   @{ML text}
  4702 
  4703 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4704 definitions, equations, inequations etc., 'concl' printing only the
  4705 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4706 to print the specified premise.  TermStyle.add_style provides an ML
  4707 interface for introducing further styles.  See also the "LaTeX Sugar"
  4708 document practical applications.  The ML antiquotation prints
  4709 type-checked ML expressions verbatim.
  4710 
  4711 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4712 and 'text' support optional locale specification '(in loc)', which
  4713 specifies the default context for interpreting antiquotations.  For
  4714 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4715 
  4716 * Option 'locale=NAME' of antiquotations specifies an alternative
  4717 context interpreting the subsequent argument.  For example: @{thm
  4718 [locale=lattice] inf_assoc}.
  4719 
  4720 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4721 a proof context.
  4722 
  4723 * Proper output of antiquotations for theory commands involving a
  4724 proof context (such as 'locale' or 'theorem (in loc) ...').
  4725 
  4726 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4727 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4728 
  4729 * isatool usedir: new option -C (default true) controls whether option
  4730 -D should include a copy of the original document directory; -C false
  4731 prevents unwanted effects such as copying of administrative CVS data.
  4732 
  4733 
  4734 *** Pure ***
  4735 
  4736 * Considerably improved version of 'constdefs' command.  Now performs
  4737 automatic type-inference of declared constants; additional support for
  4738 local structure declarations (cf. locales and HOL records), see also
  4739 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4740 sequential dependencies of definitions within a single 'constdefs'
  4741 section; moreover, the declared name needs to be an identifier.  If
  4742 all fails, consider to fall back on 'consts' and 'defs' separately.
  4743 
  4744 * Improved indexed syntax and implicit structures.  First of all,
  4745 indexed syntax provides a notational device for subscripted
  4746 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4747 expressions.  Secondly, in a local context with structure
  4748 declarations, number indexes \<^sub>n or the empty index (default
  4749 number 1) refer to a certain fixed variable implicitly; option
  4750 show_structs controls printing of implicit structures.  Typical
  4751 applications of these concepts involve record types and locales.
  4752 
  4753 * New command 'no_syntax' removes grammar declarations (and
  4754 translations) resulting from the given syntax specification, which is
  4755 interpreted in the same manner as for the 'syntax' command.
  4756 
  4757 * 'Advanced' translation functions (parse_translation etc.) may depend
  4758 on the signature of the theory context being presently used for
  4759 parsing/printing, see also isar-ref manual.
  4760 
  4761 * Improved 'oracle' command provides a type-safe interface to turn an
  4762 ML expression of type theory -> T -> term into a primitive rule of
  4763 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4764 is already included here); see also FOL/ex/IffExample.thy;
  4765 INCOMPATIBILITY.
  4766 
  4767 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4768 before); "cI" is no longer bound, use "c.intro" instead.
  4769 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4770 axclasses vs. locales.
  4771 
  4772 * Improved internal renaming of symbolic identifiers -- attach primes
  4773 instead of base 26 numbers.
  4774 
  4775 * New flag show_question_marks controls printing of leading question
  4776 marks in schematic variable names.
  4777 
  4778 * In schematic variable names, *any* symbol following \<^isub> or
  4779 \<^isup> is now treated as part of the base name.  For example, the
  4780 following works without printing of awkward ".0" indexes:
  4781 
  4782   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4783     by simp
  4784 
  4785 * Inner syntax includes (*(*nested*) comments*).
  4786 
  4787 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4788 annotations as "(00...)".
  4789 
  4790 * Clear separation of logical types and nonterminals, where the latter
  4791 may only occur in 'syntax' specifications or type abbreviations.
  4792 Before that distinction was only partially implemented via type class
  4793 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4794 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4795 exotic syntax specifications may require further adaption
  4796 (e.g. Cube/Cube.thy).
  4797 
  4798 * Removed obsolete type class "logic", use the top sort {} instead.
  4799 Note that non-logical types should be declared as 'nonterminals'
  4800 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4801 specifications.
  4802 
  4803 * Attributes 'induct' and 'cases': type or set names may now be
  4804 locally fixed variables as well.
  4805 
  4806 * Simplifier: can now control the depth to which conditional rewriting
  4807 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4808 Limit.
  4809 
  4810 * Simplifier: simplification procedures may now take the current
  4811 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4812 interface), which is very useful for calling the Simplifier
  4813 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4814 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4815 low-level mk_simproc no longer applies Logic.varify internally, to
  4816 allow for use in a context of fixed variables.
  4817 
  4818 * thin_tac now works even if the assumption being deleted contains !!
  4819 or ==>.  More generally, erule now works even if the major premise of
  4820 the elimination rule contains !! or ==>.
  4821 
  4822 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4823 
  4824 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4825 from Pure, which contains all common declarations already.  Both
  4826 theories are defined via plain Isabelle/Isar .thy files.
  4827 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4828 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4829 use isatool fixcpure to adapt your theory and ML sources.
  4830 
  4831 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4832 selections of theorems in named facts via index ranges.
  4833 
  4834 * 'print_theorems': in theory mode, really print the difference
  4835 wrt. the last state (works for interactive theory development only),
  4836 in proof mode print all local facts (cf. 'print_facts');
  4837 
  4838 * 'hide': option '(open)' hides only base names.
  4839 
  4840 * More efficient treatment of intermediate checkpoints in interactive
  4841 theory development.
  4842 
  4843 * Code generator is now invoked via code_module (incremental code
  4844 generation) and code_library (modular code generation, ML structures
  4845 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4846 must be quoted when used as identifiers.
  4847 
  4848 * New 'value' command for reading, evaluating and printing terms using
  4849 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4850 quoted when used as identifier.
  4851 
  4852 
  4853 *** Locales ***
  4854 
  4855 * New commands for the interpretation of locale expressions in
  4856 theories (1), locales (2) and proof contexts (3).  These generate
  4857 proof obligations from the expression specification.  After the
  4858 obligations have been discharged, theorems of the expression are added
  4859 to the theory, target locale or proof context.  The synopsis of the
  4860 commands is a follows:
  4861 
  4862   (1) interpretation expr inst
  4863   (2) interpretation target < expr
  4864   (3) interpret expr inst
  4865 
  4866 Interpretation in theories and proof contexts require a parameter
  4867 instantiation of terms from the current context.  This is applied to
  4868 specifications and theorems of the interpreted expression.
  4869 Interpretation in locales only permits parameter renaming through the
  4870 locale expression.  Interpretation is smart in that interpretations
  4871 that are active already do not occur in proof obligations, neither are
  4872 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4873 inspect active interpretations of a particular locale.  For details,
  4874 see the Isar Reference manual.  Examples can be found in
  4875 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4876 
  4877 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4878 'interpret' instead.
  4879 
  4880 * New context element 'constrains' for adding type constraints to
  4881 parameters.
  4882 
  4883 * Context expressions: renaming of parameters with syntax
  4884 redeclaration.
  4885 
  4886 * Locale declaration: 'includes' disallowed.
  4887 
  4888 * Proper static binding of attribute syntax -- i.e. types / terms /
  4889 facts mentioned as arguments are always those of the locale definition
  4890 context, independently of the context of later invocations.  Moreover,
  4891 locale operations (renaming and type / term instantiation) are applied
  4892 to attribute arguments as expected.
  4893 
  4894 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4895 actual attributes; rare situations may require Attrib.attribute to
  4896 embed those attributes into Attrib.src that lack concrete syntax.
  4897 Attribute implementations need to cooperate properly with the static
  4898 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4899 Attrib.XXX_thm etc. already do the right thing without further
  4900 intervention.  Only unusual applications -- such as "where" or "of"
  4901 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4902 on the context and the facts involved -- may have to assign parsed
  4903 values to argument tokens explicitly.
  4904 
  4905 * Changed parameter management in theorem generation for long goal
  4906 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4907 theorem statement in rare situations.
  4908 
  4909 * Locale inspection command 'print_locale' omits notes elements.  Use
  4910 'print_locale!' to have them included in the output.
  4911 
  4912 
  4913 *** Provers ***
  4914 
  4915 * Provers/hypsubst.ML: improved version of the subst method, for
  4916 single-step rewriting: it now works in bound variable contexts. New is
  4917 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4918 rewrite a different subterm than the original subst method, which is
  4919 still available as 'simplesubst'.
  4920 
  4921 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4922 and quasi orders.
  4923 
  4924 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4925 reflexive-transitive closure of relations.
  4926 
  4927 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4928 limit (previously hard-coded with a value of 20) user-definable.
  4929 
  4930 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4931 is peformed already.  Object-logics merely need to finish their
  4932 initial simpset configuration as before.  INCOMPATIBILITY.
  4933 
  4934 
  4935 *** HOL ***
  4936 
  4937 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4938 
  4939   syntax (epsilon)
  4940     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4941 
  4942 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4943 and x-symbol; use option '-m epsilon' to get it actually printed.
  4944 Moreover, the mathematically important symbolic identifier \<epsilon>
  4945 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4946 
  4947 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  4948 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  4949 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  4950 support corresponding Isar calculations.
  4951 
  4952 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  4953 instead of ":".
  4954 
  4955 * theory SetInterval: changed the syntax for open intervals:
  4956 
  4957   Old       New
  4958   {..n(}    {..<n}
  4959   {)n..}    {n<..}
  4960   {m..n(}   {m..<n}
  4961   {)m..n}   {m<..n}
  4962   {)m..n(}  {m<..<n}
  4963 
  4964 The old syntax is still supported but will disappear in the next
  4965 release.  For conversion use the following Emacs search and replace
  4966 patterns (these are not perfect but work quite well):
  4967 
  4968   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  4969   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  4970 
  4971 * Theory Commutative_Ring (in Library): method comm_ring for proving
  4972 equalities in commutative rings; method 'algebra' provides a generic
  4973 interface.
  4974 
  4975 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  4976 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  4977 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  4978 be a tuple pattern.
  4979 
  4980 Some new syntax forms are available:
  4981 
  4982   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  4983   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  4984   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  4985   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  4986 
  4987 The latter form "\<Sum>x < k. e" used to be based on a separate
  4988 function "Summation", which has been discontinued.
  4989 
  4990 * theory Finite_Set: in structured induction proofs, the insert case
  4991 is now 'case (insert x F)' instead of the old counterintuitive 'case
  4992 (insert F x)'.
  4993 
  4994 * The 'refute' command has been extended to support a much larger
  4995 fragment of HOL, including axiomatic type classes, constdefs and
  4996 typedefs, inductive datatypes and recursion.
  4997 
  4998 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  4999 Requires zChaff with proof generation to be installed.  See
  5000 HOL/ex/SAT_Examples.thy for examples.
  5001 
  5002 * Datatype induction via method 'induct' now preserves the name of the
  5003 induction variable. For example, when proving P(xs::'a list) by
  5004 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  5005 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  5006 in unstructured proof scripts.
  5007 
  5008 * Reworked implementation of records.  Improved scalability for
  5009 records with many fields, avoiding performance problems for type
  5010 inference. Records are no longer composed of nested field types, but
  5011 of nested extension types. Therefore the record type only grows linear
  5012 in the number of extensions and not in the number of fields.  The
  5013 top-level (users) view on records is preserved.  Potential
  5014 INCOMPATIBILITY only in strange cases, where the theory depends on the
  5015 old record representation. The type generated for a record is called
  5016 <record_name>_ext_type.
  5017 
  5018 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  5019 proofs triggered by a record definition or a simproc (if
  5020 quick_and_dirty is enabled).  Definitions of large records can take
  5021 quite long.
  5022 
  5023 New simproc record_upd_simproc for simplification of multiple record
  5024 updates enabled by default.  Moreover, trivial updates are also
  5025 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  5026 occasionally, since simplification is more powerful by default.
  5027 
  5028 * typedef: proper support for polymorphic sets, which contain extra
  5029 type-variables in the term.
  5030 
  5031 * Simplifier: automatically reasons about transitivity chains
  5032 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  5033 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  5034 old proofs break occasionally as simplification may now solve more
  5035 goals than previously.
  5036 
  5037 * Simplifier: converts x <= y into x = y if assumption y <= x is
  5038 present.  Works for all partial orders (class "order"), in particular
  5039 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  5040 just like y <= x.
  5041 
  5042 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  5043 bound variable or a constant then the let is unfolded.  Otherwise
  5044 first a is simplified to b, and then f b is simplified to g. If
  5045 possible we abstract b from g arriving at "let x = b in h x",
  5046 otherwise we unfold the let and arrive at g.  The simproc can be
  5047 enabled/disabled by the reference use_let_simproc.  Potential
  5048 INCOMPATIBILITY since simplification is more powerful by default.
  5049 
  5050 * Classical reasoning: the meson method now accepts theorems as arguments.
  5051 
  5052 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  5053 jobs to provide advice on the provability of subgoals.
  5054 
  5055 * Theory OrderedGroup and Ring_and_Field: various additions and
  5056 improvements to faciliate calculations involving equalities and
  5057 inequalities.
  5058 
  5059 The following theorems have been eliminated or modified
  5060 (INCOMPATIBILITY):
  5061 
  5062   abs_eq             now named abs_of_nonneg
  5063   abs_of_ge_0        now named abs_of_nonneg
  5064   abs_minus_eq       now named abs_of_nonpos
  5065   imp_abs_id         now named abs_of_nonneg
  5066   imp_abs_neg_id     now named abs_of_nonpos
  5067   mult_pos           now named mult_pos_pos
  5068   mult_pos_le        now named mult_nonneg_nonneg
  5069   mult_pos_neg_le    now named mult_nonneg_nonpos
  5070   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5071   mult_neg           now named mult_neg_neg
  5072   mult_neg_le        now named mult_nonpos_nonpos
  5073 
  5074 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5075      
  5076      zero_le_square
  5077      not_square_less_zero 
  5078 
  5079   The following lemmas have been deleted from Real/RealPow:
  5080   
  5081      realpow_zero_zero
  5082      realpow_two
  5083      realpow_less
  5084      zero_le_power
  5085      realpow_two_le
  5086      abs_realpow_two
  5087      realpow_two_abs     
  5088 
  5089 * Theory Parity: added rules for simplifying exponents.
  5090 
  5091 * Theory List:
  5092 
  5093 The following theorems have been eliminated or modified
  5094 (INCOMPATIBILITY):
  5095 
  5096   list_all_Nil       now named list_all.simps(1)
  5097   list_all_Cons      now named list_all.simps(2)
  5098   list_all_conv      now named list_all_iff
  5099   set_mem_eq         now named mem_iff
  5100 
  5101 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5102 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5103 
  5104 
  5105 *** HOL-Complex ***
  5106 
  5107 * Theory RealDef: better support for embedding natural numbers and
  5108 integers in the reals.
  5109 
  5110 The following theorems have been eliminated or modified
  5111 (INCOMPATIBILITY):
  5112 
  5113   exp_ge_add_one_self  now requires no hypotheses
  5114   real_of_int_add      reversed direction of equality (use [symmetric])
  5115   real_of_int_minus    reversed direction of equality (use [symmetric])
  5116   real_of_int_diff     reversed direction of equality (use [symmetric])
  5117   real_of_int_mult     reversed direction of equality (use [symmetric])
  5118 
  5119 * Theory RComplete: expanded support for floor and ceiling functions.
  5120 
  5121 * Theory Ln is new, with properties of the natural logarithm
  5122 
  5123 * Hyperreal: There is a new type constructor "star" for making
  5124 nonstandard types.  The old type names are now type synonyms:
  5125 
  5126   hypreal = real star
  5127   hypnat = nat star
  5128   hcomplex = complex star
  5129 
  5130 * Hyperreal: Many groups of similarly-defined constants have been
  5131 replaced by polymorphic versions (INCOMPATIBILITY):
  5132 
  5133   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5134 
  5135   starset      <-- starsetNat, starsetC
  5136   *s*          <-- *sNat*, *sc*
  5137   starset_n    <-- starsetNat_n, starsetC_n
  5138   *sn*         <-- *sNatn*, *scn*
  5139   InternalSets <-- InternalNatSets, InternalCSets
  5140 
  5141   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5142   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5143   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5144   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5145   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5146 
  5147 * Hyperreal: Many type-specific theorems have been removed in favor of
  5148 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5149 
  5150   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5151   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5152   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5153   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5154   right_minus <-- hypreal_add_minus
  5155   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5156   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5157   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5158   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5159   mult_1_right <-- hcomplex_mult_one_right
  5160   mult_zero_left <-- hcomplex_mult_zero_left
  5161   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5162   right_distrib <-- hypnat_add_mult_distrib2
  5163   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5164   right_inverse <-- hypreal_mult_inverse
  5165   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5166   order_refl <-- {hypreal,hypnat}_le_refl
  5167   order_trans <-- {hypreal,hypnat}_le_trans
  5168   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5169   order_less_le <-- {hypreal,hypnat}_less_le
  5170   linorder_linear <-- {hypreal,hypnat}_le_linear
  5171   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5172   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5173   add_nonneg_nonneg <-- hypreal_le_add_order
  5174 
  5175 * Hyperreal: Separate theorems having to do with type-specific
  5176 versions of constants have been merged into theorems that apply to the
  5177 new polymorphic constants (INCOMPATIBILITY):
  5178 
  5179   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5180   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5181   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5182   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5183   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5184   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5185   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5186   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5187   STAR_diff <-- {STAR,STARC}_diff
  5188   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5189     STARC_hcomplex_of_complex}_image_subset
  5190   starset_n_Un <-- starset{Nat,C}_n_Un
  5191   starset_n_Int <-- starset{Nat,C}_n_Int
  5192   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5193   starset_n_diff <-- starset{Nat,C}_n_diff
  5194   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5195   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5196   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5197   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5198   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5199   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5200   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5201   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5202   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5203   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5204   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5205   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5206   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5207   starfun_diff <-- starfun{C,RC,CR}_diff
  5208   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5209   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5210   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5211   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5212   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5213   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5214   starfun_Id <-- starfunC_Id
  5215   starfun_approx <-- starfun{Nat,CR}_approx
  5216   starfun_capprox <-- starfun{C,RC}_capprox
  5217   starfun_abs <-- starfunNat_rabs
  5218   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5219   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5220   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5221   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5222   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5223   starfun_add_approx <-- starfunCR_add_approx
  5224   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5225   starfun_divide <-- starfun{C,CR,RC}_divide
  5226   starfun_n <-- starfun{Nat,C}_n
  5227   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5228   starfun_n_add <-- starfun{Nat,C}_n_add
  5229   starfun_n_add_minus <-- starfunNat_n_add_minus
  5230   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5231   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5232   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5233 
  5234   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5235   star_n_minus <-- {hypreal,hcomplex}_minus
  5236   star_n_diff <-- {hypreal,hcomplex}_diff
  5237   star_n_mult <-- {hypreal,hcomplex}_mult
  5238   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5239   star_n_le <-- {hypreal,hypnat}_le
  5240   star_n_less <-- {hypreal,hypnat}_less
  5241   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5242   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5243   star_n_abs <-- hypreal_hrabs
  5244   star_n_divide <-- hcomplex_divide
  5245 
  5246   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5247   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5248   star_of_diff <-- hypreal_of_real_diff
  5249   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5250   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5251   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5252   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5253   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5254   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5255   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5256   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5257   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5258   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5259   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5260   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5261   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5262   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5263   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5264   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5265   star_of_power <-- hypreal_of_real_power
  5266   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5267 
  5268 * Hyperreal: new method "transfer" that implements the transfer
  5269 principle of nonstandard analysis. With a subgoal that mentions
  5270 nonstandard types like "'a star", the command "apply transfer"
  5271 replaces it with an equivalent one that mentions only standard types.
  5272 To be successful, all free variables must have standard types; non-
  5273 standard variables must have explicit universal quantifiers.
  5274 
  5275 * Hyperreal: A theory of Taylor series.
  5276 
  5277 
  5278 *** HOLCF ***
  5279 
  5280 * Discontinued special version of 'constdefs' (which used to support
  5281 continuous functions) in favor of the general Pure one with full
  5282 type-inference.
  5283 
  5284 * New simplification procedure for solving continuity conditions; it
  5285 is much faster on terms with many nested lambda abstractions (cubic
  5286 instead of exponential time).
  5287 
  5288 * New syntax for domain package: selector names are now optional.
  5289 Parentheses should be omitted unless argument is lazy, for example:
  5290 
  5291   domain 'a stream = cons "'a" (lazy "'a stream")
  5292 
  5293 * New command 'fixrec' for defining recursive functions with pattern
  5294 matching; defining multiple functions with mutual recursion is also
  5295 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5296 sinr, or any data constructor defined by the domain package. The given
  5297 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5298 syntax and examples.
  5299 
  5300 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5301 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5302 but the proof obligation additionally includes an admissibility
  5303 requirement. The packages generate instances of class cpo or pcpo,
  5304 with continuity and strictness theorems for Rep and Abs.
  5305 
  5306 * HOLCF: Many theorems have been renamed according to a more standard naming
  5307 scheme (INCOMPATIBILITY):
  5308 
  5309   foo_inject:  "foo$x = foo$y ==> x = y"
  5310   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5311   foo_less:    "(foo$x << foo$y) = (x << y)"
  5312   foo_strict:  "foo$UU = UU"
  5313   foo_defined: "... ==> foo$x ~= UU"
  5314   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5315 
  5316 
  5317 *** ZF ***
  5318 
  5319 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5320 including the First Isomorphism Theorem (on quotienting by the kernel
  5321 of a homomorphism).
  5322 
  5323 * ZF/Simplifier: install second copy of type solver that actually
  5324 makes use of TC rules declared to Isar proof contexts (or locales);
  5325 the old version is still required for ML proof scripts.
  5326 
  5327 
  5328 *** Cube ***
  5329 
  5330 * Converted to Isar theory format; use locales instead of axiomatic
  5331 theories.
  5332 
  5333 
  5334 *** ML ***
  5335 
  5336 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5337 for ||>, ||>>, |>>,
  5338 
  5339 * Pure/library.ML no longer defines its own option datatype, but uses
  5340 that of the SML basis, which has constructors NONE and SOME instead of
  5341 None and Some, as well as exception Option.Option instead of OPTION.
  5342 The functions the, if_none, is_some, is_none have been adapted
  5343 accordingly, while Option.map replaces apsome.
  5344 
  5345 * Pure/library.ML: the exception LIST has been given up in favour of
  5346 the standard exceptions Empty and Subscript, as well as
  5347 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5348 superceded by the standard hd and tl functions etc.
  5349 
  5350 A number of basic list functions are no longer exported to the ML
  5351 toplevel, as they are variants of predefined functions.  The following
  5352 suggests how one can translate existing code:
  5353 
  5354     rev_append xs ys = List.revAppend (xs, ys)
  5355     nth_elem (i, xs) = List.nth (xs, i)
  5356     last_elem xs = List.last xs
  5357     flat xss = List.concat xss
  5358     seq fs = List.app fs
  5359     partition P xs = List.partition P xs
  5360     mapfilter f xs = List.mapPartial f xs
  5361 
  5362 * Pure/library.ML: several combinators for linear functional
  5363 transformations, notably reverse application and composition:
  5364 
  5365   x |> f                f #> g
  5366   (x, y) |-> f          f #-> g
  5367 
  5368 * Pure/library.ML: introduced/changed precedence of infix operators:
  5369 
  5370   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5371   infix 2 ?;
  5372   infix 3 o oo ooo oooo;
  5373   infix 4 ~~ upto downto;
  5374 
  5375 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5376 infix operators.
  5377 
  5378 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5379 fold_map support linear functional transformations and nesting.  For
  5380 example:
  5381 
  5382   fold f [x1, ..., xN] y =
  5383     y |> f x1 |> ... |> f xN
  5384 
  5385   (fold o fold) f [xs1, ..., xsN] y =
  5386     y |> fold f xs1 |> ... |> fold f xsN
  5387 
  5388   fold f [x1, ..., xN] =
  5389     f x1 #> ... #> f xN
  5390 
  5391   (fold o fold) f [xs1, ..., xsN] =
  5392     fold f xs1 #> ... #> fold f xsN
  5393 
  5394 * Pure/library.ML: the following selectors on type 'a option are
  5395 available:
  5396 
  5397   the:               'a option -> 'a  (*partial*)
  5398   these:             'a option -> 'a  where 'a = 'b list
  5399   the_default: 'a -> 'a option -> 'a
  5400   the_list:          'a option -> 'a list
  5401 
  5402 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5403 basic operations for association lists, following natural argument
  5404 order; moreover the explicit equality predicate passed here avoids
  5405 potentially expensive polymorphic runtime equality checks.
  5406 The old functions may be expressed as follows:
  5407 
  5408   assoc = uncurry (AList.lookup (op =))
  5409   assocs = these oo AList.lookup (op =)
  5410   overwrite = uncurry (AList.update (op =)) o swap
  5411 
  5412 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5413 
  5414   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5415   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5416 
  5417 replacing make_keylist and keyfilter (occassionally used)
  5418 Naive rewrites:
  5419 
  5420   make_keylist = AList.make
  5421   keyfilter = AList.find (op =)
  5422 
  5423 * eq_fst and eq_snd now take explicit equality parameter, thus
  5424   avoiding eqtypes. Naive rewrites:
  5425 
  5426     eq_fst = eq_fst (op =)
  5427     eq_snd = eq_snd (op =)
  5428 
  5429 * Removed deprecated apl and apr (rarely used).
  5430   Naive rewrites:
  5431 
  5432     apl (n, op) =>>= curry op n
  5433     apr (op, m) =>>= fn n => op (n, m)
  5434 
  5435 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5436 provides a reasonably efficient light-weight implementation of sets as
  5437 lists.
  5438 
  5439 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5440 few new operations; existing lookup and update are now curried to
  5441 follow natural argument order (for use with fold etc.);
  5442 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5443 
  5444 * Pure/General: output via the Isabelle channels of
  5445 writeln/warning/error etc. is now passed through Output.output, with a
  5446 hook for arbitrary transformations depending on the print_mode
  5447 (cf. Output.add_mode -- the first active mode that provides a output
  5448 function wins).  Already formatted output may be embedded into further
  5449 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5450 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5451 accommodate easy composition of diagnostic messages etc.  Programmers
  5452 rarely need to care about Output.output or Output.raw at all, with
  5453 some notable exceptions: Output.output is required when bypassing the
  5454 standard channels (writeln etc.), or in token translations to produce
  5455 properly formatted results; Output.raw is required when capturing
  5456 already output material that will eventually be presented to the user
  5457 a second time.  For the default print mode, both Output.output and
  5458 Output.raw have no effect.
  5459 
  5460 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5461 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5462 cumulative results are displayed at the end of a batch session.
  5463 
  5464 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5465 replaced by File.platform_path and File.shell_path (with appropriate
  5466 hooks).  This provides a clean interface for unusual systems where the
  5467 internal and external process view of file names are different.
  5468 
  5469 * Pure: more efficient orders for basic syntactic entities: added
  5470 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5471 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5472 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5473 orders now -- potential INCOMPATIBILITY for code that depends on a
  5474 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5475 Library.sort_strings on result).
  5476 
  5477 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5478 fold_types traverse types/terms from left to right, observing natural
  5479 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5480 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5481 
  5482 * Pure: name spaces have been refined, with significant changes of the
  5483 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5484 to extern(_table).  The plain name entry path is superceded by a
  5485 general 'naming' context, which also includes the 'policy' to produce
  5486 a fully qualified name and external accesses of a fully qualified
  5487 name; NameSpace.extend is superceded by context dependent
  5488 Sign.declare_name.  Several theory and proof context operations modify
  5489 the naming context.  Especially note Theory.restore_naming and
  5490 ProofContext.restore_naming to get back to a sane state; note that
  5491 Theory.add_path is no longer sufficient to recover from
  5492 Theory.absolute_path in particular.
  5493 
  5494 * Pure: new flags short_names (default false) and unique_names
  5495 (default true) for controlling output of qualified names.  If
  5496 short_names is set, names are printed unqualified.  If unique_names is
  5497 reset, the name prefix is reduced to the minimum required to achieve
  5498 the original result when interning again, even if there is an overlap
  5499 with earlier declarations.
  5500 
  5501 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5502 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5503 (useful for printing error messages).  INCOMPATIBILITY.
  5504 
  5505 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5506 Theory.theory are now identified, referring to the universal
  5507 Context.theory (see Pure/context.ML).  Actual signature and theory
  5508 content is managed as theory data.  The old code and interfaces were
  5509 spread over many files and structures; the new arrangement introduces
  5510 considerable INCOMPATIBILITY to gain more clarity:
  5511 
  5512   Context -- theory management operations (name, identity, inclusion,
  5513     parents, ancestors, merge, etc.), plus generic theory data;
  5514 
  5515   Sign -- logical signature and syntax operations (declaring consts,
  5516     types, etc.), plus certify/read for common entities;
  5517 
  5518   Theory -- logical theory operations (stating axioms, definitions,
  5519     oracles), plus a copy of logical signature operations (consts,
  5520     types, etc.); also a few basic management operations (Theory.copy,
  5521     Theory.merge, etc.)
  5522 
  5523 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5524 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5525 for convenience -- they merely return the theory.
  5526 
  5527 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5528 
  5529 * Pure: the Isar proof context type is already defined early in Pure
  5530 as Context.proof (note that ProofContext.context and Proof.context are
  5531 aliases, where the latter is the preferred name).  This enables other
  5532 Isabelle components to refer to that type even before Isar is present.
  5533 
  5534 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5535 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5536 any of these kinds.  For example, Sign.intern typeK is now
  5537 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5538 Theory.hide_types.  Also note that former
  5539 Theory.hide_classes/types/consts are now
  5540 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5541 internalize their arguments!  INCOMPATIBILITY.
  5542 
  5543 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5544 datatype thmref (with constructors Name and NameSelection) instead of
  5545 plain string -- INCOMPATIBILITY;
  5546 
  5547 * Pure: cases produced by proof methods specify options, where NONE
  5548 means to remove case bindings -- INCOMPATIBILITY in
  5549 (RAW_)METHOD_CASES.
  5550 
  5551 * Pure: the following operations retrieve axioms or theorems from a
  5552 theory node or theory hierarchy, respectively:
  5553 
  5554   Theory.axioms_of: theory -> (string * term) list
  5555   Theory.all_axioms_of: theory -> (string * term) list
  5556   PureThy.thms_of: theory -> (string * thm) list
  5557   PureThy.all_thms_of: theory -> (string * thm) list
  5558 
  5559 * Pure: print_tac now outputs the goal through the trace channel.
  5560 
  5561 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5562 Reference Toplevel.debug (default false) controls detailed printing
  5563 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5564 controls execution profiling -- set to 1 for time and 2 for space
  5565 (both increase the runtime).
  5566 
  5567 * Isar session: The initial use of ROOT.ML is now always timed,
  5568 i.e. the log will show the actual process times, in contrast to the
  5569 elapsed wall-clock time that the outer shell wrapper produces.
  5570 
  5571 * Simplifier: improved handling of bound variables (nameless
  5572 representation, avoid allocating new strings).  Simprocs that invoke
  5573 the Simplifier recursively should use Simplifier.inherit_bounds to
  5574 avoid local name clashes.  Failure to do so produces warnings
  5575 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5576 for further details.
  5577 
  5578 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5579 bindings for all theorems stored within a given theory; this may help
  5580 in porting non-Isar theories to Isar ones, while keeping ML proof
  5581 scripts for the time being.
  5582 
  5583 * ML operator HTML.with_charset specifies the charset begin used for
  5584 generated HTML files.  For example:
  5585 
  5586   HTML.with_charset "utf-8" use_thy "Hebrew";
  5587   HTML.with_charset "utf-8" use_thy "Chinese";
  5588 
  5589 
  5590 *** System ***
  5591 
  5592 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5593 isabelle, isatool etc.).
  5594 
  5595 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5596 isatool doc, isatool mkdir, display_drafts etc.).
  5597 
  5598 * isatool usedir: option -f allows specification of the ML file to be
  5599 used by Isabelle; default is ROOT.ML.
  5600 
  5601 * New isatool version outputs the version identifier of the Isabelle
  5602 distribution being used.
  5603 
  5604 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5605 (containing Boolean satisfiability problems) into Isabelle/HOL
  5606 theories.
  5607 
  5608 
  5609 
  5610 New in Isabelle2004 (April 2004)
  5611 --------------------------------
  5612 
  5613 *** General ***
  5614 
  5615 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5616   Replaces linorder.ML.
  5617 
  5618 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5619   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5620   (\<a>...\<z>), are now considered normal letters, and can therefore
  5621   be used anywhere where an ASCII letter (a...zA...Z) has until
  5622   now. COMPATIBILITY: This obviously changes the parsing of some
  5623   terms, especially where a symbol has been used as a binder, say
  5624   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5625   as an identifier.  Fix it by inserting a space around former
  5626   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5627   existing theory and ML files.
  5628 
  5629 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5630 
  5631 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5632   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5633   a normal (but invisible) letter. For multiple letter subscripts repeat
  5634   \<^isub> like this: x\<^isub>1\<^isub>2.
  5635 
  5636 * Pure: There are now sub-/superscripts that can span more than one
  5637   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5638   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5639   superscript. The new control characters are not identifier parts.
  5640 
  5641 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5642   content of "..." to the latex file instead of \isacntrl... . The "..."
  5643   may consist of any printable characters excluding the end bracket >.
  5644 
  5645 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5646   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5647   declare constants "final", which prevents their being given a definition
  5648   later.  It is useful for constants whose behaviour is fixed axiomatically
  5649   rather than definitionally, such as the meta-logic connectives.
  5650 
  5651 * Pure: 'instance' now handles general arities with general sorts
  5652   (i.e. intersections of classes),
  5653 
  5654 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5655   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5656   It can be changed to alter the colors/layout of generated pages.
  5657 
  5658 
  5659 *** Isar ***
  5660 
  5661 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5662   cut_tac, subgoal_tac and thin_tac:
  5663   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5664     locales are no longer forced to write Isar proof scripts.
  5665     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5666     emulations.
  5667   - INCOMPATIBILITY: names of variables to be instantiated may no
  5668     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5669     This is consistent with the instantiation attribute "where".
  5670 
  5671 * Attributes "where" and "of":
  5672   - Now take type variables of instantiated theorem into account when reading
  5673     the instantiation string.  This fixes a bug that caused instantiated
  5674     theorems to have too special types in some circumstances.
  5675   - "where" permits explicit instantiations of type variables.
  5676 
  5677 * Calculation commands "moreover" and "also" no longer interfere with
  5678   current facts ("this"), admitting arbitrary combinations with "then"
  5679   and derived forms.
  5680 
  5681 * Locales:
  5682   - Goal statements involving the context element "includes" no longer
  5683     generate theorems with internal delta predicates (those ending on
  5684     "_axioms") in the premise.
  5685     Resolve particular premise with <locale>.intro to obtain old form.
  5686   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5687     specification and "includes" elements in goal statement.
  5688   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5689     [intro?] and [elim?] (respectively) by default.
  5690   - Experimental command for instantiation of locales in proof contexts:
  5691         instantiate <label>[<attrs>]: <loc>
  5692     Instantiates locale <loc> and adds all its theorems to the current context
  5693     taking into account their attributes.  Label and attrs are optional
  5694     modifiers, like in theorem declarations.  If present, names of
  5695     instantiated theorems are qualified with <label>, and the attributes
  5696     <attrs> are applied after any attributes these theorems might have already.
  5697       If the locale has assumptions, a chained fact of the form
  5698     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5699     are derived.  The command does not support old-style locales declared
  5700     with "locale (open)".
  5701       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5702 
  5703 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5704   (Isar) contexts.
  5705 
  5706 
  5707 *** HOL ***
  5708 
  5709 * Proof import: new image HOL4 contains the imported library from
  5710   the HOL4 system with about 2500 theorems. It is imported by
  5711   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5712   can be used like any other Isabelle image.  See
  5713   HOL/Import/HOL/README for more information.
  5714 
  5715 * Simplifier:
  5716   - Much improved handling of linear and partial orders.
  5717     Reasoners for linear and partial orders are set up for type classes
  5718     "linorder" and "order" respectively, and are added to the default simpset
  5719     as solvers.  This means that the simplifier can build transitivity chains
  5720     to solve goals from the assumptions.
  5721   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5722     of blast or auto after simplification become unnecessary because the goal
  5723     is solved by simplification already.
  5724 
  5725 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5726     all proved in axiomatic type classes for semirings, rings and fields.
  5727 
  5728 * Numerics:
  5729   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5730     now formalized using the Ring_and_Field theory mentioned above.
  5731   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5732     than before, because now they are set up once in a generic manner.
  5733   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5734     Look for the general versions in Ring_and_Field (and Power if they concern
  5735     exponentiation).
  5736 
  5737 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5738 
  5739 * Records:
  5740   - Record types are now by default printed with their type abbreviation
  5741     instead of the list of all field types. This can be configured via
  5742     the reference "print_record_type_abbr".
  5743   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5744     (not enabled by default).
  5745   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5746     EX x. x = sel r to True (not enabled by default).
  5747   - Tactic "record_split_simp_tac" to split and simplify records added.
  5748 
  5749 * 'specification' command added, allowing for definition by
  5750   specification.  There is also an 'ax_specification' command that
  5751   introduces the new constants axiomatically.
  5752 
  5753 * arith(_tac) is now able to generate counterexamples for reals as well.
  5754 
  5755 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5756 
  5757 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5758   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5759 
  5760 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5761   matrix theory to linear programming.
  5762 
  5763 * Unions and Intersections:
  5764   The latex output syntax of UN and INT has been changed
  5765   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5766   i.e. the index formulae has become a subscript.
  5767   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5768 
  5769 * Unions and Intersections over Intervals:
  5770   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5771   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5772   like in normal math, and corresponding versions for < and for intersection.
  5773 
  5774 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5775   lexicographic dictonary ordering has been added as "lexord".
  5776 
  5777 * ML: the legacy theory structures Int and List have been removed. They had
  5778   conflicted with ML Basis Library structures having the same names.
  5779 
  5780 * 'refute' command added to search for (finite) countermodels.  Only works
  5781   for a fragment of HOL.  The installation of an external SAT solver is
  5782   highly recommended.  See "HOL/Refute.thy" for details.
  5783 
  5784 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5785   formulae under an assignment of free variables to random values.
  5786   In contrast to 'refute', it can deal with inductive datatypes,
  5787   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5788   for examples.
  5789 
  5790 
  5791 *** HOLCF ***
  5792 
  5793 * Streams now come with concatenation and are part of the HOLCF image
  5794 
  5795 
  5796 
  5797 New in Isabelle2003 (May 2003)
  5798 ------------------------------
  5799 
  5800 *** General ***
  5801 
  5802 * Provers/simplifier:
  5803 
  5804   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5805     Assumptions are now subject to complete mutual simplification,
  5806     not just from left to right. The simplifier now preserves
  5807     the order of assumptions.
  5808 
  5809     Potential INCOMPATIBILITY:
  5810 
  5811     -- simp sometimes diverges where the old version did
  5812        not, e.g. invoking simp on the goal
  5813 
  5814         [| P (f x); y = x; f x = f y |] ==> Q
  5815 
  5816        now gives rise to the infinite reduction sequence
  5817 
  5818         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5819 
  5820        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5821        kind of problem.
  5822 
  5823     -- Tactics combining classical reasoner and simplification (such as auto)
  5824        are also affected by this change, because many of them rely on
  5825        simp. They may sometimes diverge as well or yield a different numbers
  5826        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5827        in case of problems. Sometimes subsequent calls to the classical
  5828        reasoner will fail because a preceeding call to the simplifier too
  5829        eagerly simplified the goal, e.g. deleted redundant premises.
  5830 
  5831   - The simplifier trace now shows the names of the applied rewrite rules
  5832 
  5833   - You can limit the number of recursive invocations of the simplifier
  5834     during conditional rewriting (where the simplifie tries to solve the
  5835     conditions before applying the rewrite rule):
  5836     ML "simp_depth_limit := n"
  5837     where n is an integer. Thus you can force termination where previously
  5838     the simplifier would diverge.
  5839 
  5840   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5841 
  5842   - No longer aborts on failed congruence proof.  Instead, the
  5843     congruence is ignored.
  5844 
  5845 * Pure: New generic framework for extracting programs from constructive
  5846   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5847   as HOL/Extraction for some case studies.
  5848 
  5849 * Pure: The main goal of the proof state is no longer shown by default, only
  5850 the subgoals. This behaviour is controlled by a new flag.
  5851    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5852 (ML: Proof.show_main_goal).
  5853 
  5854 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5855 rules whose conclusion matches subgoal 1:
  5856       PG menu: Isabelle/Isar -> Show me -> matching rules
  5857 The rules are ordered by how closely they match the subgoal.
  5858 In particular, rules that solve a subgoal outright are displayed first
  5859 (or rather last, the way they are printed).
  5860 (ML: ProofGeneral.print_intros())
  5861 
  5862 * Pure: New flag trace_unify_fail causes unification to print
  5863 diagnostic information (PG: in trace buffer) when it fails. This is
  5864 useful for figuring out why single step proofs like rule, erule or
  5865 assumption failed.
  5866 
  5867 * Pure: Locale specifications now produce predicate definitions
  5868 according to the body of text (covering assumptions modulo local
  5869 definitions); predicate "loc_axioms" covers newly introduced text,
  5870 while "loc" is cumulative wrt. all included locale expressions; the
  5871 latter view is presented only on export into the global theory
  5872 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5873 on the old view without predicates;
  5874 
  5875 * Pure: predefined locales "var" and "struct" are useful for sharing
  5876 parameters (as in CASL, for example); just specify something like
  5877 ``var x + var y + struct M'' as import;
  5878 
  5879 * Pure: improved thms_containing: proper indexing of facts instead of
  5880 raw theorems; check validity of results wrt. current name space;
  5881 include local facts of proof configuration (also covers active
  5882 locales), cover fixed variables in index; may use "_" in term
  5883 specification; an optional limit for the number of printed facts may
  5884 be given (the default is 40);
  5885 
  5886 * Pure: disallow duplicate fact bindings within new-style theory files
  5887 (batch-mode only);
  5888 
  5889 * Provers: improved induct method: assumptions introduced by case
  5890 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5891 the goal statement); "foo" still refers to all facts collectively;
  5892 
  5893 * Provers: the function blast.overloaded has been removed: all constants
  5894 are regarded as potentially overloaded, which improves robustness in exchange
  5895 for slight decrease in efficiency;
  5896 
  5897 * Provers/linorder: New generic prover for transitivity reasoning over
  5898 linear orders.  Note: this prover is not efficient!
  5899 
  5900 * Isar: preview of problems to finish 'show' now produce an error
  5901 rather than just a warning (in interactive mode);
  5902 
  5903 
  5904 *** HOL ***
  5905 
  5906 * arith(_tac)
  5907 
  5908  - Produces a counter example if it cannot prove a goal.
  5909    Note that the counter example may be spurious if the goal is not a formula
  5910    of quantifier-free linear arithmetic.
  5911    In ProofGeneral the counter example appears in the trace buffer.
  5912 
  5913  - Knows about div k and mod k where k is a numeral of type nat or int.
  5914 
  5915  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5916    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5917    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5918 
  5919 * simp's arithmetic capabilities have been enhanced a bit: it now
  5920 takes ~= in premises into account (by performing a case split);
  5921 
  5922 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5923 are distributed over a sum of terms;
  5924 
  5925 * New tactic "trans_tac" and method "trans" instantiate
  5926 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5927 "<=", "<" and "=").
  5928 
  5929 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5930 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5931 
  5932 * 'typedef' command has new option "open" to suppress the set
  5933 definition;
  5934 
  5935 * functions Min and Max on finite sets have been introduced (theory
  5936 Finite_Set);
  5937 
  5938 * attribute [symmetric] now works for relations as well; it turns
  5939 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5940 
  5941 * induct over a !!-quantified statement (say !!x1..xn):
  5942   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5943 
  5944 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5945 %x. None. Warning: empty_def now refers to the previously hidden definition
  5946 of the empty set.
  5947 
  5948 * Algebra: formalization of classical algebra.  Intended as base for
  5949 any algebraic development in Isabelle.  Currently covers group theory
  5950 (up to Sylow's theorem) and ring theory (Universal Property of
  5951 Univariate Polynomials).  Contributions welcome;
  5952 
  5953 * GroupTheory: deleted, since its material has been moved to Algebra;
  5954 
  5955 * Complex: new directory of the complex numbers with numeric constants,
  5956 nonstandard complex numbers, and some complex analysis, standard and
  5957 nonstandard (Jacques Fleuriot);
  5958 
  5959 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  5960 
  5961 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  5962 Fleuriot);
  5963 
  5964 * Real/HahnBanach: updated and adapted to locales;
  5965 
  5966 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  5967 Gray and Kramer);
  5968 
  5969 * UNITY: added the Meier-Sanders theory of progress sets;
  5970 
  5971 * MicroJava: bytecode verifier and lightweight bytecode verifier
  5972 as abstract algorithms, instantiated to the JVM;
  5973 
  5974 * Bali: Java source language formalization. Type system, operational
  5975 semantics, axiomatic semantics. Supported language features:
  5976 classes, interfaces, objects,virtual methods, static methods,
  5977 static/instance fields, arrays, access modifiers, definite
  5978 assignment, exceptions.
  5979 
  5980 
  5981 *** ZF ***
  5982 
  5983 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  5984 universe, etc.);
  5985 
  5986 * Main ZF: virtually all theories converted to new-style format;
  5987 
  5988 
  5989 *** ML ***
  5990 
  5991 * Pure: Tactic.prove provides sane interface for internal proofs;
  5992 omits the infamous "standard" operation, so this is more appropriate
  5993 than prove_goalw_cterm in many situations (e.g. in simprocs);
  5994 
  5995 * Pure: improved error reporting of simprocs;
  5996 
  5997 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  5998 up simprocs;
  5999 
  6000 
  6001 *** Document preparation ***
  6002 
  6003 * uses \par instead of \\ for line breaks in theory text. This may
  6004 shift some page breaks in large documents. To get the old behaviour
  6005 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  6006 
  6007 * minimized dependencies of isabelle.sty and isabellesym.sty on
  6008 other packages
  6009 
  6010 * \<euro> now needs package babel/greek instead of marvosym (which
  6011 broke \Rightarrow)
  6012 
  6013 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  6014 textcomp package)
  6015 
  6016 
  6017 
  6018 New in Isabelle2002 (March 2002)
  6019 --------------------------------
  6020 
  6021 *** Document preparation ***
  6022 
  6023 * greatly simplified document preparation setup, including more
  6024 graceful interpretation of isatool usedir -i/-d/-D options, and more
  6025 instructive isatool mkdir; users should basically be able to get
  6026 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  6027 users may run a separate document processing stage manually like this:
  6028 "isatool usedir -D output HOL Test && isatool document Test/output";
  6029 
  6030 * theory dependency graph may now be incorporated into documents;
  6031 isatool usedir -g true will produce session_graph.eps/.pdf for use
  6032 with \includegraphics of LaTeX;
  6033 
  6034 * proper spacing of consecutive markup elements, especially text
  6035 blocks after section headings;
  6036 
  6037 * support bold style (for single symbols only), input syntax is like
  6038 this: "\<^bold>\<alpha>" or "\<^bold>A";
  6039 
  6040 * \<bullet> is now output as bold \cdot by default, which looks much
  6041 better in printed text;
  6042 
  6043 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  6044 note that these symbols are currently unavailable in Proof General /
  6045 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  6046 
  6047 * isatool latex no longer depends on changed TEXINPUTS, instead
  6048 isatool document copies the Isabelle style files to the target
  6049 location;
  6050 
  6051 
  6052 *** Isar ***
  6053 
  6054 * Pure/Provers: improved proof by cases and induction;
  6055   - 'case' command admits impromptu naming of parameters (such as
  6056     "case (Suc n)");
  6057   - 'induct' method divinates rule instantiation from the inductive
  6058     claim; no longer requires excessive ?P bindings for proper
  6059     instantiation of cases;
  6060   - 'induct' method properly enumerates all possibilities of set/type
  6061     rules; as a consequence facts may be also passed through *type*
  6062     rules without further ado;
  6063   - 'induct' method now derives symbolic cases from the *rulified*
  6064     rule (before it used to rulify cases stemming from the internal
  6065     atomized version); this means that the context of a non-atomic
  6066     statement becomes is included in the hypothesis, avoiding the
  6067     slightly cumbersome show "PROP ?case" form;
  6068   - 'induct' may now use elim-style induction rules without chaining
  6069     facts, using ``missing'' premises from the goal state; this allows
  6070     rules stemming from inductive sets to be applied in unstructured
  6071     scripts, while still benefitting from proper handling of non-atomic
  6072     statements; NB: major inductive premises need to be put first, all
  6073     the rest of the goal is passed through the induction;
  6074   - 'induct' proper support for mutual induction involving non-atomic
  6075     rule statements (uses the new concept of simultaneous goals, see
  6076     below);
  6077   - append all possible rule selections, but only use the first
  6078     success (no backtracking);
  6079   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  6080   - undeclared rule case names default to numbers 1, 2, 3, ...;
  6081   - added 'print_induct_rules' (covered by help item in recent Proof
  6082     General versions);
  6083   - moved induct/cases attributes to Pure, methods to Provers;
  6084   - generic method setup instantiated for FOL and HOL;
  6085 
  6086 * Pure: support multiple simultaneous goal statements, for example
  6087 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  6088 meta-level mechanism, this acts as if several individual goals had
  6089 been stated separately; in particular common proof methods need to be
  6090 repeated in order to cover all claims; note that a single elimination
  6091 step is *not* sufficient to establish the two conjunctions, so this
  6092 fails:
  6093 
  6094   assume "A & B" then have A and B ..   (*".." fails*)
  6095 
  6096 better use "obtain" in situations as above; alternative refer to
  6097 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  6098 
  6099 * Pure: proper integration with ``locales''; unlike the original
  6100 version by Florian Kammller, Isar locales package high-level proof
  6101 contexts rather than raw logical ones (e.g. we admit to include
  6102 attributes everywhere); operations on locales include merge and
  6103 rename; support for implicit arguments (``structures''); simultaneous
  6104 type-inference over imports and text; see also HOL/ex/Locales.thy for
  6105 some examples;
  6106 
  6107 * Pure: the following commands have been ``localized'', supporting a
  6108 target locale specification "(in name)": 'lemma', 'theorem',
  6109 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  6110 stored both within the locale and at the theory level (exported and
  6111 qualified by the locale name);
  6112 
  6113 * Pure: theory goals may now be specified in ``long'' form, with
  6114 ad-hoc contexts consisting of arbitrary locale elements. for example
  6115 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  6116 definitions may be given, too); the result is a meta-level rule with
  6117 the context elements being discharged in the obvious way;
  6118 
  6119 * Pure: new proof command 'using' allows to augment currently used
  6120 facts after a goal statement ('using' is syntactically analogous to
  6121 'apply', but acts on the goal's facts only); this allows chained facts
  6122 to be separated into parts given before and after a claim, as in
  6123 ``from a and b have C using d and e <proof>'';
  6124 
  6125 * Pure: renamed "antecedent" case to "rule_context";
  6126 
  6127 * Pure: new 'judgment' command records explicit information about the
  6128 object-logic embedding (used by several tools internally); no longer
  6129 use hard-wired "Trueprop";
  6130 
  6131 * Pure: added 'corollary' command;
  6132 
  6133 * Pure: fixed 'token_translation' command;
  6134 
  6135 * Pure: removed obsolete 'exported' attribute;
  6136 
  6137 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  6138 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  6139 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  6140 
  6141 * Pure: method 'atomize' presents local goal premises as object-level
  6142 statements (atomic meta-level propositions); setup controlled via
  6143 rewrite rules declarations of 'atomize' attribute; example
  6144 application: 'induct' method with proper rule statements in improper
  6145 proof *scripts*;
  6146 
  6147 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  6148 now consider the syntactic context of assumptions, giving a better
  6149 chance to get type-inference of the arguments right (this is
  6150 especially important for locales);
  6151 
  6152 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  6153 mode;
  6154 
  6155 * Pure/obtain: the formal conclusion "thesis", being marked as
  6156 ``internal'', may no longer be reference directly in the text;
  6157 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  6158 situations;
  6159 
  6160 * Pure: generic 'sym' attribute which declares a rule both as pure
  6161 'elim?' and for the 'symmetric' operation;
  6162 
  6163 * Pure: marginal comments ``--'' may now occur just anywhere in the
  6164 text; the fixed correlation with particular command syntax has been
  6165 discontinued;
  6166 
  6167 * Pure: new method 'rules' is particularly well-suited for proof
  6168 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  6169 but often produces more compact proof terms with less detours;
  6170 
  6171 * Pure/Provers/classical: simplified integration with pure rule
  6172 attributes and methods; the classical "intro?/elim?/dest?"
  6173 declarations coincide with the pure ones; the "rule" method no longer
  6174 includes classically swapped intros; "intro" and "elim" methods no
  6175 longer pick rules from the context; also got rid of ML declarations
  6176 AddXIs/AddXEs/AddXDs; all of this has some potential for
  6177 INCOMPATIBILITY;
  6178 
  6179 * Provers/classical: attribute 'swapped' produces classical inversions
  6180 of introduction rules;
  6181 
  6182 * Provers/simplifier: 'simplified' attribute may refer to explicit
  6183 rules instead of full simplifier context; 'iff' attribute handles
  6184 conditional rules;
  6185 
  6186 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  6187 
  6188 * HOL: 'recdef' now fails on unfinished automated proofs, use
  6189 "(permissive)" option to recover old behavior;
  6190 
  6191 * HOL: 'inductive' no longer features separate (collective) attributes
  6192 for 'intros' (was found too confusing);
  6193 
  6194 * HOL: properly declared induction rules less_induct and
  6195 wf_induct_rule;
  6196 
  6197 
  6198 *** HOL ***
  6199 
  6200 * HOL: moved over to sane numeral syntax; the new policy is as
  6201 follows:
  6202 
  6203   - 0 and 1 are polymorphic constants, which are defined on any
  6204   numeric type (nat, int, real etc.);
  6205 
  6206   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  6207   binary representation internally;
  6208 
  6209   - type nat has special constructor Suc, and generally prefers Suc 0
  6210   over 1::nat and Suc (Suc 0) over 2::nat;
  6211 
  6212 This change may cause significant problems of INCOMPATIBILITY; here
  6213 are some hints on converting existing sources:
  6214 
  6215   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  6216   entities, so expressions involving "-" (unary or binary minus) need
  6217   to be spaced properly;
  6218 
  6219   - existing occurrences of "1" may need to be constraint "1::nat" or
  6220   even replaced by Suc 0; similar for old "2";
  6221 
  6222   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  6223 
  6224   - remove all special provisions on numerals in proofs;
  6225 
  6226 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  6227 representation (depends on bin_arith_simps in the default context);
  6228 
  6229 * HOL: symbolic syntax for x^2 (numeral 2);
  6230 
  6231 * HOL: the class of all HOL types is now called "type" rather than
  6232 "term"; INCOMPATIBILITY, need to adapt references to this type class
  6233 in axclass/classes, instance/arities, and (usually rare) occurrences
  6234 in typings (of consts etc.); internally the class is called
  6235 "HOL.type", ML programs should refer to HOLogic.typeS;
  6236 
  6237 * HOL/record package improvements:
  6238   - new derived operations "fields" to build a partial record section,
  6239     "extend" to promote a fixed record to a record scheme, and
  6240     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  6241     declared as simp by default;
  6242   - shared operations ("more", "fields", etc.) now need to be always
  6243     qualified) --- potential INCOMPATIBILITY;
  6244   - removed "make_scheme" operations (use "make" with "extend") --
  6245     INCOMPATIBILITY;
  6246   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  6247   - provides cases/induct rules for use with corresponding Isar
  6248     methods (for concrete records, record schemes, concrete more
  6249     parts, and schematic more parts -- in that order);
  6250   - internal definitions directly based on a light-weight abstract
  6251     theory of product types over typedef rather than datatype;
  6252 
  6253 * HOL: generic code generator for generating executable ML code from
  6254 specifications; specific support for HOL constructs such as inductive
  6255 datatypes and sets, as well as recursive functions; can be invoked
  6256 via 'generate_code' theory section;
  6257 
  6258 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  6259 
  6260 * HOL: consolidated and renamed several theories.  In particular:
  6261         Ord.thy has been absorbed into HOL.thy
  6262         String.thy has been absorbed into List.thy
  6263 
  6264 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  6265 (beware of argument permutation!);
  6266 
  6267 * HOL: linorder_less_split superseded by linorder_cases;
  6268 
  6269 * HOL/List: "nodups" renamed to "distinct";
  6270 
  6271 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  6272 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  6273   - Ex_def has changed, now need to use some_eq_ex
  6274 
  6275 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  6276 in this (rare) case use:
  6277 
  6278   delSWrapper "split_all_tac"
  6279   addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
  6280 
  6281 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
  6282 MAY FAIL;
  6283 
  6284 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
  6285 Isabelle's type classes, ^ on functions and relations has too general
  6286 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be
  6287 necessary to attach explicit type constraints;
  6288 
  6289 * HOL/Relation: the prefix name of the infix "O" has been changed from
  6290 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been
  6291 renamed accordingly (eg "compI" -> "rel_compI").
  6292 
  6293 * HOL: syntax translations now work properly with numerals and records
  6294 expressions;
  6295 
  6296 * HOL: bounded abstraction now uses syntax "%" / "\<lambda>" instead
  6297 of "lam" -- INCOMPATIBILITY;
  6298 
  6299 * HOL: got rid of some global declarations (potential INCOMPATIBILITY
  6300 for ML tools): const "()" renamed "Product_Type.Unity", type "unit"
  6301 renamed "Product_Type.unit";
  6302 
  6303 * HOL: renamed rtrancl_into_rtrancl2 to converse_rtrancl_into_rtrancl
  6304 
  6305 * HOL: removed obsolete theorem "optionE" (use "option.exhaust", or
  6306 the "cases" method);
  6307 
  6308 * HOL/GroupTheory: group theory examples including Sylow's theorem (by
  6309 Florian Kammller);
  6310 
  6311 * HOL/IMP: updated and converted to new-style theory format; several
  6312 parts turned into readable document, with proper Isar proof texts and
  6313 some explanations (by Gerwin Klein);
  6314 
  6315 * HOL-Real: added Complex_Numbers (by Gertrud Bauer);
  6316 
  6317 * HOL-Hyperreal is now a logic image;
  6318 
  6319 
  6320 *** HOLCF ***
  6321 
  6322 * Isar: consts/constdefs supports mixfix syntax for continuous
  6323 operations;
  6324 
  6325 * Isar: domain package adapted to new-style theory format, e.g. see
  6326 HOLCF/ex/Dnat.thy;
  6327 
  6328 * theory Lift: proper use of rep_datatype lift instead of ML hacks --
  6329 potential INCOMPATIBILITY; now use plain induct_tac instead of former
  6330 lift.induct_tac, always use UU instead of Undef;
  6331 
  6332 * HOLCF/IMP: updated and converted to new-style theory;
  6333 
  6334 
  6335 *** ZF ***
  6336 
  6337 * Isar: proper integration of logic-specific tools and packages,
  6338 including theory commands '(co)inductive', '(co)datatype',
  6339 'rep_datatype', 'inductive_cases', as well as methods 'ind_cases',
  6340 'induct_tac', 'case_tac', and 'typecheck' (with attribute 'TC');
  6341 
  6342 * theory Main no longer includes AC; for the Axiom of Choice, base
  6343 your theory on Main_ZFC;
  6344 
  6345 * the integer library now covers quotients and remainders, with many
  6346 laws relating division to addition, multiplication, etc.;
  6347 
  6348 * ZF/UNITY: Chandy and Misra's UNITY is now available in ZF, giving a
  6349 typeless version of the formalism;
  6350 
  6351 * ZF/AC, Coind, IMP, Resid: updated and converted to new-style theory
  6352 format;
  6353 
  6354 * ZF/Induct: new directory for examples of inductive definitions,
  6355 including theory Multiset for multiset orderings; converted to
  6356 new-style theory format;
  6357 
  6358 * ZF: many new theorems about lists, ordinals, etc.;
  6359 
  6360 
  6361 *** General ***
  6362 
  6363 * Pure/kernel: meta-level proof terms (by Stefan Berghofer); reference
  6364 variable proof controls level of detail: 0 = no proofs (only oracle
  6365 dependencies), 1 = lemma dependencies, 2 = compact proof terms; see
  6366 also ref manual for further ML interfaces;
  6367 
  6368 * Pure/axclass: removed obsolete ML interface
  6369 goal_subclass/goal_arity;
  6370 
  6371 * Pure/syntax: new token syntax "num" for plain numerals (without "#"
  6372 of "xnum"); potential INCOMPATIBILITY, since -0, -1 etc. are now
  6373 separate tokens, so expressions involving minus need to be spaced
  6374 properly;
  6375 
  6376 * Pure/syntax: support non-oriented infixes, using keyword "infix"
  6377 rather than "infixl" or "infixr";
  6378 
  6379 * Pure/syntax: concrete syntax for dummy type variables admits genuine
  6380 sort constraint specifications in type inference; e.g. "x::_::foo"
  6381 ensures that the type of "x" is of sort "foo" (but not necessarily a
  6382 type variable);
  6383 
  6384 * Pure/syntax: print modes "type_brackets" and "no_type_brackets"
  6385 control output of nested => (types); the default behavior is
  6386 "type_brackets";
  6387 
  6388 * Pure/syntax: builtin parse translation for "_constify" turns valued
  6389 tokens into AST constants;
  6390 
  6391 * Pure/syntax: prefer later declarations of translations and print
  6392 translation functions; potential INCOMPATIBILITY: need to reverse
  6393 multiple declarations for same syntax element constant;
  6394 
  6395 * Pure/show_hyps reset by default (in accordance to existing Isar
  6396 practice);
  6397 
  6398 * Provers/classical: renamed addaltern to addafter, addSaltern to
  6399 addSafter;
  6400 
  6401 * Provers/clasimp: ``iff'' declarations now handle conditional rules
  6402 as well;
  6403 
  6404 * system: tested support for MacOS X; should be able to get Isabelle +
  6405 Proof General to work in a plain Terminal after installing Poly/ML
  6406 (e.g. from the Isabelle distribution area) and GNU bash alone
  6407 (e.g. from http://www.apple.com); full X11, XEmacs and X-Symbol
  6408 support requires further installations, e.g. from
  6409 http://fink.sourceforge.net/);
  6410 
  6411 * system: support Poly/ML 4.1.1 (able to manage larger heaps);
  6412 
  6413 * system: reduced base memory usage by Poly/ML (approx. 20 MB instead
  6414 of 40 MB), cf. ML_OPTIONS;
  6415 
  6416 * system: Proof General keywords specification is now part of the
  6417 Isabelle distribution (see etc/isar-keywords.el);
  6418 
  6419 * system: support for persistent Proof General sessions (refrain from
  6420 outdating all loaded theories on startup); user may create writable
  6421 logic images like this: ``isabelle -q HOL Test'';
  6422 
  6423 * system: smart selection of Isabelle process versus Isabelle
  6424 interface, accommodates case-insensitive file systems (e.g. HFS+); may
  6425 run both "isabelle" and "Isabelle" even if file names are badly
  6426 damaged (executable inspects the case of the first letter of its own
  6427 name); added separate "isabelle-process" and "isabelle-interface";
  6428 
  6429 * system: refrain from any attempt at filtering input streams; no
  6430 longer support ``8bit'' encoding of old isabelle font, instead proper
  6431 iso-latin characters may now be used; the related isatools
  6432 "symbolinput" and "nonascii" have disappeared as well;
  6433 
  6434 * system: removed old "xterm" interface (the print modes "xterm" and
  6435 "xterm_color" are still available for direct use in a suitable
  6436 terminal);
  6437 
  6438 
  6439 
  6440 New in Isabelle99-2 (February 2001)
  6441 -----------------------------------
  6442 
  6443 *** Overview of INCOMPATIBILITIES ***
  6444 
  6445 * HOL: please note that theories in the Library and elsewhere often use the
  6446 new-style (Isar) format; to refer to their theorems in an ML script you must
  6447 bind them to ML identifers by e.g.      val thm_name = thm "thm_name";
  6448 
  6449 * HOL: inductive package no longer splits induction rule aggressively,
  6450 but only as far as specified by the introductions given; the old
  6451 format may be recovered via ML function complete_split_rule or attribute
  6452 'split_rule (complete)';
  6453 
  6454 * HOL: induct renamed to lfp_induct, lfp_Tarski to lfp_unfold,
  6455 gfp_Tarski to gfp_unfold;
  6456 
  6457 * HOL: contrapos, contrapos2 renamed to contrapos_nn, contrapos_pp;
  6458 
  6459 * HOL: infix "dvd" now has priority 50 rather than 70 (because it is a
  6460 relation); infix "^^" has been renamed "``"; infix "``" has been
  6461 renamed "`"; "univalent" has been renamed "single_valued";
  6462 
  6463 * HOL/Real: "rinv" and "hrinv" replaced by overloaded "inverse"
  6464 operation;
  6465 
  6466 * HOLCF: infix "`" has been renamed "$"; the symbol syntax is \<cdot>;
  6467 
  6468 * Isar: 'obtain' no longer declares "that" fact as simp/intro;
  6469 
  6470 * Isar/HOL: method 'induct' now handles non-atomic goals; as a
  6471 consequence, it is no longer monotonic wrt. the local goal context
  6472 (which is now passed through the inductive cases);
  6473 
  6474 * Document preparation: renamed standard symbols \<ll> to \<lless> and
  6475 \<gg> to \<ggreater>;
  6476 
  6477 
  6478 *** Document preparation ***
  6479 
  6480 * \isabellestyle{NAME} selects version of Isabelle output (currently
  6481 available: are "it" for near math-mode best-style output, "sl" for
  6482 slanted text style, and "tt" for plain type-writer; if no
  6483 \isabellestyle command is given, output is according to slanted
  6484 type-writer);
  6485 
  6486 * support sub/super scripts (for single symbols only), input syntax is
  6487 like this: "A\<^sup>*" or "A\<^sup>\<star>";
  6488 
  6489 * some more standard symbols; see Appendix A of the system manual for
  6490 the complete list of symbols defined in isabellesym.sty;
  6491 
  6492 * improved isabelle style files; more abstract symbol implementation
  6493 (should now use \isamath{...} and \isatext{...} in custom symbol
  6494 definitions);
  6495 
  6496 * antiquotation @{goals} and @{subgoals} for output of *dynamic* goals
  6497 state; Note that presentation of goal states does not conform to
  6498 actual human-readable proof documents.  Please do not include goal
  6499 states into document output unless you really know what you are doing!
  6500 
  6501 * proper indentation of antiquoted output with proportional LaTeX
  6502 fonts;
  6503 
  6504 * no_document ML operator temporarily disables LaTeX document
  6505 generation;
  6506 
  6507 * isatool unsymbolize tunes sources for plain ASCII communication;
  6508 
  6509 
  6510 *** Isar ***
  6511 
  6512 * Pure: Isar now suffers initial goal statements to contain unbound
  6513 schematic variables (this does not conform to actual readable proof
  6514 documents, due to unpredictable outcome and non-compositional proof
  6515 checking); users who know what they are doing may use schematic goals
  6516 for Prolog-style synthesis of proven results;
  6517 
  6518 * Pure: assumption method (an implicit finishing) now handles actual
  6519 rules as well;
  6520 
  6521 * Pure: improved 'obtain' --- moved to Pure, insert "that" into
  6522 initial goal, declare "that" only as Pure intro (only for single
  6523 steps); the "that" rule assumption may now be involved in implicit
  6524 finishing, thus ".." becomes a feasible for trivial obtains;
  6525 
  6526 * Pure: default proof step now includes 'intro_classes'; thus trivial
  6527 instance proofs may be performed by "..";
  6528 
  6529 * Pure: ?thesis / ?this / "..." now work for pure meta-level
  6530 statements as well;
  6531 
  6532 * Pure: more robust selection of calculational rules;
  6533 
  6534 * Pure: the builtin notion of 'finished' goal now includes the ==-refl
  6535 rule (as well as the assumption rule);
  6536 
  6537 * Pure: 'thm_deps' command visualizes dependencies of theorems and
  6538 lemmas, using the graph browser tool;
  6539 
  6540 * Pure: predict failure of "show" in interactive mode;
  6541 
  6542 * Pure: 'thms_containing' now takes actual terms as arguments;
  6543 
  6544 * HOL: improved method 'induct' --- now handles non-atomic goals
  6545 (potential INCOMPATIBILITY); tuned error handling;
  6546 
  6547 * HOL: cases and induct rules now provide explicit hints about the
  6548 number of facts to be consumed (0 for "type" and 1 for "set" rules);
  6549 any remaining facts are inserted into the goal verbatim;
  6550 
  6551 * HOL: local contexts (aka cases) may now contain term bindings as
  6552 well; the 'cases' and 'induct' methods new provide a ?case binding for
  6553 the result to be shown in each case;
  6554 
  6555 * HOL: added 'recdef_tc' command;
  6556 
  6557 * isatool convert assists in eliminating legacy ML scripts;
  6558 
  6559 
  6560 *** HOL ***
  6561 
  6562 * HOL/Library: a collection of generic theories to be used together
  6563 with main HOL; the theory loader path already includes this directory
  6564 by default; the following existing theories have been moved here:
  6565 HOL/Induct/Multiset, HOL/Induct/Acc (as Accessible_Part), HOL/While
  6566 (as While_Combinator), HOL/Lex/Prefix (as List_Prefix);
  6567 
  6568 * HOL/Unix: "Some aspects of Unix file-system security", a typical
  6569 modelling and verification task performed in Isabelle/HOL +
  6570 Isabelle/Isar + Isabelle document preparation (by Markus Wenzel).
  6571 
  6572 * HOL/Algebra: special summation operator SUM no longer exists, it has
  6573 been replaced by setsum; infix 'assoc' now has priority 50 (like
  6574 'dvd'); axiom 'one_not_zero' has been moved from axclass 'ring' to
  6575 'domain', this makes the theory consistent with mathematical
  6576 literature;
  6577 
  6578 * HOL basics: added overloaded operations "inverse" and "divide"
  6579 (infix "/"), syntax for generic "abs" operation, generic summation
  6580 operator \<Sum>;
  6581 
  6582 * HOL/typedef: simplified package, provide more useful rules (see also
  6583 HOL/subset.thy);
  6584 
  6585 * HOL/datatype: induction rule for arbitrarily branching datatypes is
  6586 now expressed as a proper nested rule (old-style tactic scripts may
  6587 require atomize_strip_tac to cope with non-atomic premises);
  6588 
  6589 * HOL: renamed theory "Prod" to "Product_Type", renamed "split" rule
  6590 to "split_conv" (old name still available for compatibility);
  6591 
  6592 * HOL: improved concrete syntax for strings (e.g. allows translation
  6593 rules with string literals);
  6594 
  6595 * HOL-Real-Hyperreal: this extends HOL-Real with the hyperreals
  6596  and Fleuriot's mechanization of analysis, including the transcendental
  6597  functions for the reals;
  6598 
  6599 * HOL/Real, HOL/Hyperreal: improved arithmetic simplification;
  6600 
  6601 
  6602 *** CTT ***
  6603 
  6604 * CTT: x-symbol support for Pi, Sigma, -->, : (membership); note that
  6605 "lam" is displayed as TWO lambda-symbols
  6606 
  6607 * CTT: theory Main now available, containing everything (that is, Bool
  6608 and Arith);
  6609 
  6610 
  6611 *** General ***
  6612 
  6613 * Pure: the Simplifier has been implemented properly as a derived rule
  6614 outside of the actual kernel (at last!); the overall performance
  6615 penalty in practical applications is about 50%, while reliability of
  6616 the Isabelle inference kernel has been greatly improved;
  6617 
  6618 * print modes "brackets" and "no_brackets" control output of nested =>
  6619 (types) and ==> (props); the default behaviour is "brackets";
  6620 
  6621 * Provers: fast_tac (and friends) now handle actual object-logic rules
  6622 as assumptions as well;
  6623 
  6624 * system: support Poly/ML 4.0;
  6625 
  6626 * system: isatool install handles KDE version 1 or 2;
  6627 
  6628 
  6629 
  6630 New in Isabelle99-1 (October 2000)
  6631 ----------------------------------
  6632 
  6633 *** Overview of INCOMPATIBILITIES ***
  6634 
  6635 * HOL: simplification of natural numbers is much changed; to partly
  6636 recover the old behaviour (e.g. to prevent n+n rewriting to #2*n)
  6637 issue the following ML commands:
  6638 
  6639   Delsimprocs Nat_Numeral_Simprocs.cancel_numerals;
  6640   Delsimprocs [Nat_Numeral_Simprocs.combine_numerals];
  6641 
  6642 * HOL: simplification no longer dives into case-expressions; this is
  6643 controlled by "t.weak_case_cong" for each datatype t;
  6644 
  6645 * HOL: nat_less_induct renamed to less_induct;
  6646 
  6647 * HOL: systematic renaming of the SOME (Eps) rules, may use isatool
  6648 fixsome to patch .thy and .ML sources automatically;
  6649 
  6650   select_equality  -> some_equality
  6651   select_eq_Ex     -> some_eq_ex
  6652   selectI2EX       -> someI2_ex
  6653   selectI2         -> someI2
  6654   selectI          -> someI
  6655   select1_equality -> some1_equality
  6656   Eps_sym_eq       -> some_sym_eq_trivial
  6657   Eps_eq           -> some_eq_trivial
  6658 
  6659 * HOL: exhaust_tac on datatypes superceded by new generic case_tac;
  6660 
  6661 * HOL: removed obsolete theorem binding expand_if (refer to split_if
  6662 instead);
  6663 
  6664 * HOL: the recursion equations generated by 'recdef' are now called
  6665 f.simps instead of f.rules;
  6666 
  6667 * HOL: qed_spec_mp now also handles bounded ALL as well;
  6668 
  6669 * HOL: 0 is now overloaded, so the type constraint ":: nat" may
  6670 sometimes be needed;
  6671 
  6672 * HOL: the constant for "f``x" is now "image" rather than "op ``";
  6673 
  6674 * HOL: the constant for "f-``x" is now "vimage" rather than "op -``";
  6675 
  6676 * HOL: the disjoint sum is now "<+>" instead of "Plus"; the cartesian
  6677 product is now "<*>" instead of "Times"; the lexicographic product is
  6678 now "<*lex*>" instead of "**";
  6679 
  6680 * HOL: theory Sexp is now in HOL/Induct examples (it used to be part
  6681 of main HOL, but was unused); better use HOL's datatype package;
  6682 
  6683 * HOL: removed "symbols" syntax for constant "override" of theory Map;
  6684 the old syntax may be recovered as follows:
  6685 
  6686   syntax (symbols)
  6687     override  :: "('a ~=> 'b) => ('a ~=> 'b) => ('a ~=> 'b)"
  6688       (infixl "\\<oplus>" 100)
  6689 
  6690 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  6691 
  6692 * HOL/ML: even fewer consts are declared as global (see theories Ord,
  6693 Lfp, Gfp, WF); this only affects ML packages that refer to const names
  6694 internally;
  6695 
  6696 * HOL and ZF: syntax for quotienting wrt an equivalence relation
  6697 changed from A/r to A//r;
  6698 
  6699 * ZF: new treatment of arithmetic (nat & int) may break some old
  6700 proofs;
  6701 
  6702 * Isar: renamed some attributes (RS -> THEN, simplify -> simplified,
  6703 rulify -> rule_format, elimify -> elim_format, ...);
  6704 
  6705 * Isar/Provers: intro/elim/dest attributes changed; renamed
  6706 intro/intro!/intro!! flags to intro!/intro/intro? (in most cases, one
  6707 should have to change intro!! to intro? only); replaced "delrule" by
  6708 "rule del";
  6709 
  6710 * Isar/HOL: renamed "intrs" to "intros" in inductive definitions;
  6711 
  6712 * Provers: strengthened force_tac by using new first_best_tac;
  6713 
  6714 * LaTeX document preparation: several changes of isabelle.sty (see
  6715 lib/texinputs);
  6716 
  6717 
  6718 *** Document preparation ***
  6719 
  6720 * formal comments (text blocks etc.) in new-style theories may now
  6721 contain antiquotations of thm/prop/term/typ/text to be presented
  6722 according to latex print mode; concrete syntax is like this:
  6723 @{term[show_types] "f(x) = a + x"};
  6724 
  6725 * isatool mkdir provides easy setup of Isabelle session directories,
  6726 including proper document sources;
  6727 
  6728 * generated LaTeX sources are now deleted after successful run
  6729 (isatool document -c); may retain a copy somewhere else via -D option
  6730 of isatool usedir;
  6731 
  6732 * isatool usedir -D now lets isatool latex -o sty update the Isabelle
  6733 style files, achieving self-contained LaTeX sources and simplifying
  6734 LaTeX debugging;
  6735 
  6736 * old-style theories now produce (crude) LaTeX output as well;
  6737 
  6738 * browser info session directories are now self-contained (may be put
  6739 on WWW server seperately); improved graphs of nested sessions; removed
  6740 graph for 'all sessions';
  6741 
  6742 * several improvements in isabelle style files; \isabellestyle{it}
  6743 produces fake math mode output; \isamarkupheader is now \section by
  6744 default; see lib/texinputs/isabelle.sty etc.;
  6745 
  6746 
  6747 *** Isar ***
  6748 
  6749 * Isar/Pure: local results and corresponding term bindings are now
  6750 subject to Hindley-Milner polymorphism (similar to ML); this
  6751 accommodates incremental type-inference very nicely;
  6752 
  6753 * Isar/Pure: new derived language element 'obtain' supports
  6754 generalized existence reasoning;
  6755 
  6756 * Isar/Pure: new calculational elements 'moreover' and 'ultimately'
  6757 support accumulation of results, without applying any rules yet;
  6758 useful to collect intermediate results without explicit name
  6759 references, and for use with transitivity rules with more than 2
  6760 premises;
  6761 
  6762 * Isar/Pure: scalable support for case-analysis type proofs: new
  6763 'case' language element refers to local contexts symbolically, as
  6764 produced by certain proof methods; internally, case names are attached
  6765 to theorems as "tags";
  6766 
  6767 * Isar/Pure: theory command 'hide' removes declarations from
  6768 class/type/const name spaces;
  6769 
  6770 * Isar/Pure: theory command 'defs' supports option "(overloaded)" to
  6771 indicate potential overloading;
  6772 
  6773 * Isar/Pure: changed syntax of local blocks from {{ }} to { };
  6774 
  6775 * Isar/Pure: syntax of sorts made 'inner', i.e. have to write
  6776 "{a,b,c}" instead of {a,b,c};
  6777 
  6778 * Isar/Pure now provides its own version of intro/elim/dest
  6779 attributes; useful for building new logics, but beware of confusion
  6780 with the version in Provers/classical;
  6781 
  6782 * Isar/Pure: the local context of (non-atomic) goals is provided via
  6783 case name 'antecedent';
  6784 
  6785 * Isar/Pure: removed obsolete 'transfer' attribute (transfer of thms
  6786 to the current context is now done automatically);
  6787 
  6788 * Isar/Pure: theory command 'method_setup' provides a simple interface
  6789 for definining proof methods in ML;
  6790 
  6791 * Isar/Provers: intro/elim/dest attributes changed; renamed
  6792 intro/intro!/intro!! flags to intro!/intro/intro? (INCOMPATIBILITY, in
  6793 most cases, one should have to change intro!! to intro? only);
  6794 replaced "delrule" by "rule del";
  6795 
  6796 * Isar/Provers: new 'hypsubst' method, plain 'subst' method and
  6797 'symmetric' attribute (the latter supercedes [RS sym]);
  6798 
  6799 * Isar/Provers: splitter support (via 'split' attribute and 'simp'
  6800 method modifier); 'simp' method: 'only:' modifier removes loopers as
  6801 well (including splits);
  6802 
  6803 * Isar/Provers: Simplifier and Classical methods now support all kind
  6804 of modifiers used in the past, including 'cong', 'iff', etc.
  6805 
  6806 * Isar/Provers: added 'fastsimp' and 'clarsimp' methods (combination
  6807 of Simplifier and Classical reasoner);
  6808 
  6809 * Isar/HOL: new proof method 'cases' and improved version of 'induct'
  6810 now support named cases; major packages (inductive, datatype, primrec,
  6811 recdef) support case names and properly name parameters;
  6812 
  6813 * Isar/HOL: new transitivity rules for substitution in inequalities --
  6814 monotonicity conditions are extracted to be proven at end of
  6815 calculations;
  6816 
  6817 * Isar/HOL: removed 'case_split' thm binding, should use 'cases' proof
  6818 method anyway;
  6819 
  6820 * Isar/HOL: removed old expand_if = split_if; theorems if_splits =
  6821 split_if split_if_asm; datatype package provides theorems foo.splits =
  6822 foo.split foo.split_asm for each datatype;
  6823 
  6824 * Isar/HOL: tuned inductive package, rename "intrs" to "intros"
  6825 (potential INCOMPATIBILITY), emulation of mk_cases feature for proof
  6826 scripts: new 'inductive_cases' command and 'ind_cases' method; (Note:
  6827 use "(cases (simplified))" method in proper proof texts);
  6828 
  6829 * Isar/HOL: added global 'arith_split' attribute for 'arith' method;
  6830 
  6831 * Isar: names of theorems etc. may be natural numbers as well;
  6832 
  6833 * Isar: 'pr' command: optional arguments for goals_limit and
  6834 ProofContext.prems_limit; no longer prints theory contexts, but only
  6835 proof states;
  6836 
  6837 * Isar: diagnostic commands 'pr', 'thm', 'prop', 'term', 'typ' admit
  6838 additional print modes to be specified; e.g. "pr(latex)" will print
  6839 proof state according to the Isabelle LaTeX style;
  6840 
  6841 * Isar: improved support for emulating tactic scripts, including proof
  6842 methods 'rule_tac' etc., 'cut_tac', 'thin_tac', 'subgoal_tac',
  6843 'rename_tac', 'rotate_tac', 'tactic', and 'case_tac' / 'induct_tac'
  6844 (for HOL datatypes);
  6845 
  6846 * Isar: simplified (more robust) goal selection of proof methods: 1st
  6847 goal, all goals, or explicit goal specifier (tactic emulation); thus
  6848 'proof method scripts' have to be in depth-first order;
  6849 
  6850 * Isar: tuned 'let' syntax: replaced 'as' keyword by 'and';
  6851 
  6852 * Isar: removed 'help' command, which hasn't been too helpful anyway;
  6853 should instead use individual commands for printing items
  6854 (print_commands, print_methods etc.);
  6855 
  6856 * Isar: added 'nothing' --- the empty list of theorems;
  6857 
  6858 
  6859 *** HOL ***
  6860 
  6861 * HOL/MicroJava: formalization of a fragment of Java, together with a
  6862 corresponding virtual machine and a specification of its bytecode
  6863 verifier and a lightweight bytecode verifier, including proofs of
  6864 type-safety; by Gerwin Klein, Tobias Nipkow, David von Oheimb, and
  6865 Cornelia Pusch (see also the homepage of project Bali at
  6866 http://isabelle.in.tum.de/Bali/);
  6867 
  6868 * HOL/Algebra: new theory of rings and univariate polynomials, by
  6869 Clemens Ballarin;
  6870 
  6871 * HOL/NumberTheory: fundamental Theorem of Arithmetic, Chinese
  6872 Remainder Theorem, Fermat/Euler Theorem, Wilson's Theorem, by Thomas M
  6873 Rasmussen;
  6874 
  6875 * HOL/Lattice: fundamental concepts of lattice theory and order
  6876 structures, including duals, properties of bounds versus algebraic
  6877 laws, lattice operations versus set-theoretic ones, the Knaster-Tarski
  6878 Theorem for complete lattices etc.; may also serve as a demonstration
  6879 for abstract algebraic reasoning using axiomatic type classes, and
  6880 mathematics-style proof in Isabelle/Isar; by Markus Wenzel;
  6881 
  6882 * HOL/Prolog: a (bare-bones) implementation of Lambda-Prolog, by David
  6883 von Oheimb;
  6884 
  6885 * HOL/IMPP: extension of IMP with local variables and mutually
  6886 recursive procedures, by David von Oheimb;
  6887 
  6888 * HOL/Lambda: converted into new-style theory and document;
  6889 
  6890 * HOL/ex/Multiquote: example of multiple nested quotations and
  6891 anti-quotations -- basically a generalized version of de-Bruijn
  6892 representation; very useful in avoiding lifting of operations;
  6893 
  6894 * HOL/record: added general record equality rule to simpset; fixed
  6895 select-update simplification procedure to handle extended records as
  6896 well; admit "r" as field name;
  6897 
  6898 * HOL: 0 is now overloaded over the new sort "zero", allowing its use with
  6899 other numeric types and also as the identity of groups, rings, etc.;
  6900 
  6901 * HOL: new axclass plus_ac0 for addition with the AC-laws and 0 as identity.
  6902 Types nat and int belong to this axclass;
  6903 
  6904 * HOL: greatly improved simplification involving numerals of type nat, int, real:
  6905    (i + #8 + j) = Suc k simplifies to  #7 + (i + j) = k
  6906    i*j + k + j*#3*i     simplifies to  #4*(i*j) + k
  6907   two terms #m*u and #n*u are replaced by #(m+n)*u
  6908     (where #m, #n and u can implicitly be 1; this is simproc combine_numerals)
  6909   and the term/formula #m*u+x ~~ #n*u+y simplifies simplifies to #(m-n)+x ~~ y
  6910     or x ~~ #(n-m)+y, where ~~ is one of = < <= or - (simproc cancel_numerals);
  6911 
  6912 * HOL: meson_tac is available (previously in ex/meson.ML); it is a
  6913 powerful prover for predicate logic but knows nothing of clasets; see
  6914 ex/mesontest.ML and ex/mesontest2.ML for example applications;
  6915 
  6916 * HOL: new version of "case_tac" subsumes both boolean case split and
  6917 "exhaust_tac" on datatypes; INCOMPATIBILITY: exhaust_tac no longer
  6918 exists, may define val exhaust_tac = case_tac for ad-hoc portability;
  6919 
  6920 * HOL: simplification no longer dives into case-expressions: only the
  6921 selector expression is simplified, but not the remaining arms; to
  6922 enable full simplification of case-expressions for datatype t, you may
  6923 remove t.weak_case_cong from the simpset, either globally (Delcongs
  6924 [thm"t.weak_case_cong"];) or locally (delcongs [...]).
  6925 
  6926 * HOL/recdef: the recursion equations generated by 'recdef' for
  6927 function 'f' are now called f.simps instead of f.rules; if all
  6928 termination conditions are proved automatically, these simplification
  6929 rules are added to the simpset, as in primrec; rules may be named
  6930 individually as well, resulting in a separate list of theorems for
  6931 each equation;
  6932 
  6933 * HOL/While is a new theory that provides a while-combinator. It
  6934 permits the definition of tail-recursive functions without the
  6935 provision of a termination measure. The latter is necessary once the
  6936 invariant proof rule for while is applied.
  6937 
  6938 * HOL: new (overloaded) notation for the set of elements below/above
  6939 some element: {..u}, {..u(}, {l..}, {)l..}. See theory SetInterval.
  6940 
  6941 * HOL: theorems impI, allI, ballI bound as "strip";
  6942 
  6943 * HOL: new tactic induct_thm_tac: thm -> string -> int -> tactic
  6944 induct_tac th "x1 ... xn" expects th to have a conclusion of the form
  6945 P v1 ... vn and abbreviates res_inst_tac [("v1","x1"),...,("vn","xn")] th;
  6946 
  6947 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  6948 
  6949 * HOL: theory Sexp now in HOL/Induct examples (it used to be part of
  6950 main HOL, but was unused);
  6951 
  6952 * HOL: fewer consts declared as global (e.g. have to refer to
  6953 "Lfp.lfp" instead of "lfp" internally; affects ML packages only);
  6954 
  6955 * HOL: tuned AST representation of nested pairs, avoiding bogus output
  6956 in case of overlap with user translations (e.g. judgements over
  6957 tuples); (note that the underlying logical represenation is still
  6958 bogus);
  6959 
  6960 
  6961 *** ZF ***
  6962 
  6963 * ZF: simplification automatically cancels common terms in arithmetic
  6964 expressions over nat and int;
  6965 
  6966 * ZF: new treatment of nat to minimize type-checking: all operators
  6967 coerce their operands to a natural number using the function natify,
  6968 making the algebraic laws unconditional;
  6969 
  6970 * ZF: as above, for int: operators coerce their operands to an integer
  6971 using the function intify;
  6972 
  6973 * ZF: the integer library now contains many of the usual laws for the
  6974 orderings, including $<=, and monotonicity laws for $+ and $*;
  6975 
  6976 * ZF: new example ZF/ex/NatSum to demonstrate integer arithmetic
  6977 simplification;
  6978 
  6979 * FOL and ZF: AddIffs now available, giving theorems of the form P<->Q
  6980 to the simplifier and classical reasoner simultaneously;
  6981 
  6982 
  6983 *** General ***
  6984 
  6985 * Provers: blast_tac now handles actual object-logic rules as
  6986 assumptions; note that auto_tac uses blast_tac internally as well;
  6987 
  6988 * Provers: new functions rulify/rulify_no_asm: thm -> thm for turning
  6989 outer -->/All/Ball into ==>/!!; qed_spec_mp now uses rulify_no_asm;
  6990 
  6991 * Provers: delrules now handles destruct rules as well (no longer need
  6992 explicit make_elim);
  6993 
  6994 * Provers: Blast_tac now warns of and ignores "weak elimination rules" e.g.
  6995   [| inj ?f;          ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  6996 use instead the strong form,
  6997   [| inj ?f; ~ ?W ==> ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  6998 in HOL, FOL and ZF the function cla_make_elim will create such rules
  6999 from destruct-rules;
  7000 
  7001 * Provers: Simplifier.easy_setup provides a fast path to basic
  7002 Simplifier setup for new object-logics;
  7003 
  7004 * Pure: AST translation rules no longer require constant head on LHS;
  7005 
  7006 * Pure: improved name spaces: ambiguous output is qualified; support
  7007 for hiding of names;
  7008 
  7009 * system: smart setup of canonical ML_HOME, ISABELLE_INTERFACE, and
  7010 XSYMBOL_HOME; no longer need to do manual configuration in most
  7011 situations;
  7012 
  7013 * system: compression of ML heaps images may now be controlled via -c
  7014 option of isabelle and isatool usedir (currently only observed by
  7015 Poly/ML);
  7016 
  7017 * system: isatool installfonts may handle X-Symbol fonts as well (very
  7018 useful for remote X11);
  7019 
  7020 * system: provide TAGS file for Isabelle sources;
  7021 
  7022 * ML: infix 'OF' is a version of 'MRS' with more appropriate argument
  7023 order;
  7024 
  7025 * ML: renamed flags Syntax.trace_norm_ast to Syntax.trace_ast; global
  7026 timing flag supersedes proof_timing and Toplevel.trace;
  7027 
  7028 * ML: new combinators |>> and |>>> for incremental transformations
  7029 with secondary results (e.g. certain theory extensions):
  7030 
  7031 * ML: PureThy.add_defs gets additional argument to indicate potential
  7032 overloading (usually false);
  7033 
  7034 * ML: PureThy.add_thms/add_axioms/add_defs now return theorems as
  7035 results;
  7036 
  7037 
  7038 
  7039 New in Isabelle99 (October 1999)
  7040 --------------------------------
  7041 
  7042 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  7043 
  7044 * HOL: The THEN and ELSE parts of conditional expressions (if P then x else y)
  7045 are no longer simplified.  (This allows the simplifier to unfold recursive
  7046 functional programs.)  To restore the old behaviour, declare
  7047 
  7048     Delcongs [if_weak_cong];
  7049 
  7050 * HOL: Removed the obsolete syntax "Compl A"; use -A for set
  7051 complement;
  7052 
  7053 * HOL: the predicate "inj" is now defined by translation to "inj_on";
  7054 
  7055 * HOL/datatype: mutual_induct_tac no longer exists --
  7056   use induct_tac "x_1 ... x_n" instead of mutual_induct_tac ["x_1", ..., "x_n"]
  7057 
  7058 * HOL/typedef: fixed type inference for representing set; type
  7059 arguments now have to occur explicitly on the rhs as type constraints;
  7060 
  7061 * ZF: The con_defs part of an inductive definition may no longer refer
  7062 to constants declared in the same theory;
  7063 
  7064 * HOL, ZF: the function mk_cases, generated by the inductive
  7065 definition package, has lost an argument.  To simplify its result, it
  7066 uses the default simpset instead of a supplied list of theorems.
  7067 
  7068 * HOL/List: the constructors of type list are now Nil and Cons;
  7069 
  7070 * Simplifier: the type of the infix ML functions
  7071         setSSolver addSSolver setSolver addSolver
  7072 is now  simpset * solver -> simpset  where `solver' is a new abstract type
  7073 for packaging solvers. A solver is created via
  7074         mk_solver: string -> (thm list -> int -> tactic) -> solver
  7075 where the string argument is only a comment.
  7076 
  7077 
  7078 *** Proof tools ***
  7079 
  7080 * Provers/Arith/fast_lin_arith.ML contains a functor for creating a
  7081 decision procedure for linear arithmetic. Currently it is used for
  7082 types `nat', `int', and `real' in HOL (see below); it can, should and
  7083 will be instantiated for other types and logics as well.
  7084 
  7085 * The simplifier now accepts rewrite rules with flexible heads, eg
  7086      hom ?f ==> ?f(?x+?y) = ?f ?x + ?f ?y
  7087   They are applied like any rule with a non-pattern lhs, i.e. by first-order
  7088   matching.
  7089 
  7090 
  7091 *** General ***
  7092 
  7093 * New Isabelle/Isar subsystem provides an alternative to traditional
  7094 tactical theorem proving; together with the ProofGeneral/isar user
  7095 interface it offers an interactive environment for developing human
  7096 readable proof documents (Isar == Intelligible semi-automated
  7097 reasoning); for further information see isatool doc isar-ref,
  7098 src/HOL/Isar_examples and http://isabelle.in.tum.de/Isar/
  7099 
  7100 * improved and simplified presentation of theories: better HTML markup
  7101 (including colors), graph views in several sizes; isatool usedir now
  7102 provides a proper interface for user theories (via -P option); actual
  7103 document preparation based on (PDF)LaTeX is available as well (for
  7104 new-style theories only); see isatool doc system for more information;
  7105 
  7106 * native support for Proof General, both for classic Isabelle and
  7107 Isabelle/Isar;
  7108 
  7109 * ML function thm_deps visualizes dependencies of theorems and lemmas,
  7110 using the graph browser tool;
  7111 
  7112 * Isabelle manuals now also available as PDF;
  7113 
  7114 * theory loader rewritten from scratch (may not be fully
  7115 bug-compatible); old loadpath variable has been replaced by show_path,
  7116 add_path, del_path, reset_path functions; new operations such as
  7117 update_thy, touch_thy, remove_thy, use/update_thy_only (see also
  7118 isatool doc ref);
  7119 
  7120 * improved isatool install: option -k creates KDE application icon,
  7121 option -p DIR installs standalone binaries;
  7122 
  7123 * added ML_PLATFORM setting (useful for cross-platform installations);
  7124 more robust handling of platform specific ML images for SML/NJ;
  7125 
  7126 * the settings environment is now statically scoped, i.e. it is never
  7127 created again in sub-processes invoked from isabelle, isatool, or
  7128 Isabelle;
  7129 
  7130 * path element specification '~~' refers to '$ISABELLE_HOME';
  7131 
  7132 * in locales, the "assumes" and "defines" parts may be omitted if
  7133 empty;
  7134 
  7135 * new print_mode "xsymbols" for extended symbol support (e.g. genuine
  7136 long arrows);
  7137 
  7138 * new print_mode "HTML";
  7139 
  7140 * new flag show_tags controls display of tags of theorems (which are
  7141 basically just comments that may be attached by some tools);
  7142 
  7143 * Isamode 2.6 requires patch to accomodate change of Isabelle font
  7144 mode and goal output format:
  7145 
  7146 diff -r Isamode-2.6/elisp/isa-load.el Isamode/elisp/isa-load.el
  7147 244c244
  7148 <       (list (isa-getenv "ISABELLE") "-msymbols" logic-name)
  7149 ---
  7150 >       (list (isa-getenv "ISABELLE") "-misabelle_font" "-msymbols" logic-name)
  7151 diff -r Isabelle-2.6/elisp/isa-proofstate.el Isamode/elisp/isa-proofstate.el
  7152 181c181
  7153 < (defconst proofstate-proofstart-regexp "^Level [0-9]+$"
  7154 ---
  7155 > (defconst proofstate-proofstart-regexp "^Level [0-9]+"
  7156 
  7157 * function bind_thms stores lists of theorems (cf. bind_thm);
  7158 
  7159 * new shorthand tactics ftac, eatac, datac, fatac;
  7160 
  7161 * qed (and friends) now accept "" as result name; in that case the
  7162 theorem is not stored, but proper checks and presentation of the
  7163 result still apply;
  7164 
  7165 * theorem database now also indexes constants "Trueprop", "all",
  7166 "==>", "=="; thus thms_containing, findI etc. may retrieve more rules;
  7167 
  7168 
  7169 *** HOL ***
  7170 
  7171 ** HOL arithmetic **
  7172 
  7173 * There are now decision procedures for linear arithmetic over nat and
  7174 int:
  7175 
  7176 1. arith_tac copes with arbitrary formulae involving `=', `<', `<=',
  7177 `+', `-', `Suc', `min', `max' and numerical constants; other subterms
  7178 are treated as atomic; subformulae not involving type `nat' or `int'
  7179 are ignored; quantified subformulae are ignored unless they are
  7180 positive universal or negative existential. The tactic has to be
  7181 invoked by hand and can be a little bit slow. In particular, the
  7182 running time is exponential in the number of occurrences of `min' and
  7183 `max', and `-' on `nat'.
  7184 
  7185 2. fast_arith_tac is a cut-down version of arith_tac: it only takes
  7186 (negated) (in)equalities among the premises and the conclusion into
  7187 account (i.e. no compound formulae) and does not know about `min' and
  7188 `max', and `-' on `nat'. It is fast and is used automatically by the
  7189 simplifier.
  7190 
  7191 NB: At the moment, these decision procedures do not cope with mixed
  7192 nat/int formulae where the two parts interact, such as `m < n ==>
  7193 int(m) < int(n)'.
  7194 
  7195 * HOL/Numeral provides a generic theory of numerals (encoded
  7196 efficiently as bit strings); setup for types nat/int/real is in place;
  7197 INCOMPATIBILITY: since numeral syntax is now polymorphic, rather than
  7198 int, existing theories and proof scripts may require a few additional
  7199 type constraints;
  7200 
  7201 * integer division and remainder can now be performed on constant
  7202 arguments;
  7203 
  7204 * many properties of integer multiplication, division and remainder
  7205 are now available;
  7206 
  7207 * An interface to the Stanford Validity Checker (SVC) is available through the
  7208 tactic svc_tac.  Propositional tautologies and theorems of linear arithmetic
  7209 are proved automatically.  SVC must be installed separately, and its results
  7210 must be TAKEN ON TRUST (Isabelle does not check the proofs, but tags any
  7211 invocation of the underlying oracle).  For SVC see
  7212   http://verify.stanford.edu/SVC
  7213 
  7214 * IsaMakefile: the HOL-Real target now builds an actual image;
  7215 
  7216 
  7217 ** HOL misc **
  7218 
  7219 * HOL/Real/HahnBanach: the Hahn-Banach theorem for real vector spaces
  7220 (in Isabelle/Isar) -- by Gertrud Bauer;
  7221 
  7222 * HOL/BCV: generic model of bytecode verification, i.e. data-flow
  7223 analysis for assembly languages with subtypes;
  7224 
  7225 * HOL/TLA (Lamport's Temporal Logic of Actions): major reorganization
  7226 -- avoids syntactic ambiguities and treats state, transition, and
  7227 temporal levels more uniformly; introduces INCOMPATIBILITIES due to
  7228 changed syntax and (many) tactics;
  7229 
  7230 * HOL/inductive: Now also handles more general introduction rules such
  7231   as "ALL y. (y, x) : r --> y : acc r ==> x : acc r"; monotonicity
  7232   theorems are now maintained within the theory (maintained via the
  7233   "mono" attribute);
  7234 
  7235 * HOL/datatype: Now also handles arbitrarily branching datatypes
  7236   (using function types) such as
  7237 
  7238   datatype 'a tree = Atom 'a | Branch "nat => 'a tree"
  7239 
  7240 * HOL/record: record_simproc (part of the default simpset) takes care
  7241 of selectors applied to updated records; record_split_tac is no longer
  7242 part of the default claset; update_defs may now be removed from the
  7243 simpset in many cases; COMPATIBILITY: old behavior achieved by
  7244 
  7245   claset_ref () := claset() addSWrapper record_split_wrapper;
  7246   Delsimprocs [record_simproc]
  7247 
  7248 * HOL/typedef: fixed type inference for representing set; type
  7249 arguments now have to occur explicitly on the rhs as type constraints;
  7250 
  7251 * HOL/recdef (TFL): 'congs' syntax now expects comma separated list of theorem
  7252 names rather than an ML expression;
  7253 
  7254 * HOL/defer_recdef (TFL): like recdef but the well-founded relation can be
  7255 supplied later.  Program schemes can be defined, such as
  7256     "While B C s = (if B s then While B C (C s) else s)"
  7257 where the well-founded relation can be chosen after B and C have been given.
  7258 
  7259 * HOL/List: the constructors of type list are now Nil and Cons;
  7260 INCOMPATIBILITY: while [] and infix # syntax is still there, of
  7261 course, ML tools referring to List.list.op # etc. have to be adapted;
  7262 
  7263 * HOL_quantifiers flag superseded by "HOL" print mode, which is
  7264 disabled by default; run isabelle with option -m HOL to get back to
  7265 the original Gordon/HOL-style output;
  7266 
  7267 * HOL/Ord.thy: new bounded quantifier syntax (input only): ALL x<y. P,
  7268 ALL x<=y. P, EX x<y. P, EX x<=y. P;
  7269 
  7270 * HOL basic syntax simplified (more orthogonal): all variants of
  7271 All/Ex now support plain / symbolic / HOL notation; plain syntax for
  7272 Eps operator is provided as well: "SOME x. P[x]";
  7273 
  7274 * HOL/Sum.thy: sum_case has been moved to HOL/Datatype;
  7275 
  7276 * HOL/Univ.thy: infix syntax <*>, <+>, <**>, <+> eliminated and made
  7277 thus available for user theories;
  7278 
  7279 * HOLCF/IOA/Sequents: renamed 'Cons' to 'Consq' to avoid clash with
  7280 HOL/List; hardly an INCOMPATIBILITY since '>>' syntax is used all the
  7281 time;
  7282 
  7283 * HOL: new tactic smp_tac: int -> int -> tactic, which applies spec
  7284 several times and then mp;
  7285 
  7286 
  7287 *** LK ***
  7288 
  7289 * the notation <<...>> is now available as a notation for sequences of
  7290 formulas;
  7291 
  7292 * the simplifier is now installed
  7293 
  7294 * the axiom system has been generalized (thanks to Soren Heilmann)
  7295 
  7296 * the classical reasoner now has a default rule database
  7297 
  7298 
  7299 *** ZF ***
  7300 
  7301 * new primrec section allows primitive recursive functions to be given
  7302 directly (as in HOL) over datatypes and the natural numbers;
  7303 
  7304 * new tactics induct_tac and exhaust_tac for induction (or case
  7305 analysis) over datatypes and the natural numbers;
  7306 
  7307 * the datatype declaration of type T now defines the recursor T_rec;
  7308 
  7309 * simplification automatically does freeness reasoning for datatype
  7310 constructors;
  7311 
  7312 * automatic type-inference, with AddTCs command to insert new
  7313 type-checking rules;
  7314 
  7315 * datatype introduction rules are now added as Safe Introduction rules
  7316 to the claset;
  7317 
  7318 * the syntax "if P then x else y" is now available in addition to
  7319 if(P,x,y);
  7320 
  7321 
  7322 *** Internal programming interfaces ***
  7323 
  7324 * tuned simplifier trace output; new flag debug_simp;
  7325 
  7326 * structures Vartab / Termtab (instances of TableFun) offer efficient
  7327 tables indexed by indexname_ord / term_ord (compatible with aconv);
  7328 
  7329 * AxClass.axclass_tac lost the theory argument;
  7330 
  7331 * tuned current_goals_markers semantics: begin / end goal avoids
  7332 printing empty lines;
  7333 
  7334 * removed prs and prs_fn hook, which was broken because it did not
  7335 include \n in its semantics, forcing writeln to add one
  7336 uncoditionally; replaced prs_fn by writeln_fn; consider std_output:
  7337 string -> unit if you really want to output text without newline;
  7338 
  7339 * Symbol.output subject to print mode; INCOMPATIBILITY: defaults to
  7340 plain output, interface builders may have to enable 'isabelle_font'
  7341 mode to get Isabelle font glyphs as before;
  7342 
  7343 * refined token_translation interface; INCOMPATIBILITY: output length
  7344 now of type real instead of int;
  7345 
  7346 * theory loader actions may be traced via new ThyInfo.add_hook
  7347 interface (see src/Pure/Thy/thy_info.ML); example application: keep
  7348 your own database of information attached to *whole* theories -- as
  7349 opposed to intra-theory data slots offered via TheoryDataFun;
  7350 
  7351 * proper handling of dangling sort hypotheses (at last!);
  7352 Thm.strip_shyps and Drule.strip_shyps_warning take care of removing
  7353 extra sort hypotheses that can be witnessed from the type signature;
  7354 the force_strip_shyps flag is gone, any remaining shyps are simply
  7355 left in the theorem (with a warning issued by strip_shyps_warning);
  7356 
  7357 
  7358 
  7359 New in Isabelle98-1 (October 1998)
  7360 ----------------------------------
  7361 
  7362 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  7363 
  7364 * several changes of automated proof tools;
  7365 
  7366 * HOL: major changes to the inductive and datatype packages, including
  7367 some minor incompatibilities of theory syntax;
  7368 
  7369 * HOL: renamed r^-1 to 'converse' from 'inverse'; 'inj_onto' is now
  7370 called `inj_on';
  7371 
  7372 * HOL: removed duplicate thms in Arith:
  7373   less_imp_add_less  should be replaced by  trans_less_add1
  7374   le_imp_add_le      should be replaced by  trans_le_add1
  7375 
  7376 * HOL: unary minus is now overloaded (new type constraints may be
  7377 required);
  7378 
  7379 * HOL and ZF: unary minus for integers is now #- instead of #~.  In
  7380 ZF, expressions such as n#-1 must be changed to n#- 1, since #-1 is
  7381 now taken as an integer constant.
  7382 
  7383 * Pure: ML function 'theory_of' renamed to 'theory';
  7384 
  7385 
  7386 *** Proof tools ***
  7387 
  7388 * Simplifier:
  7389   1. Asm_full_simp_tac is now more aggressive.
  7390      1. It will sometimes reorient premises if that increases their power to
  7391         simplify.
  7392      2. It does no longer proceed strictly from left to right but may also
  7393         rotate premises to achieve further simplification.
  7394      For compatibility reasons there is now Asm_lr_simp_tac which is like the
  7395      old Asm_full_simp_tac in that it does not rotate premises.
  7396   2. The simplifier now knows a little bit about nat-arithmetic.
  7397 
  7398 * Classical reasoner: wrapper mechanism for the classical reasoner now
  7399 allows for selected deletion of wrappers, by introduction of names for
  7400 wrapper functionals.  This implies that addbefore, addSbefore,
  7401 addaltern, and addSaltern now take a pair (name, tactic) as argument,
  7402 and that adding two tactics with the same name overwrites the first
  7403 one (emitting a warning).
  7404   type wrapper = (int -> tactic) -> (int -> tactic)
  7405   setWrapper, setSWrapper, compWrapper and compSWrapper are replaced by
  7406   addWrapper, addSWrapper: claset * (string * wrapper) -> claset
  7407   delWrapper, delSWrapper: claset *  string            -> claset
  7408   getWrapper is renamed to appWrappers, getSWrapper to appSWrappers;
  7409 
  7410 * Classical reasoner: addbefore/addSbefore now have APPEND/ORELSE
  7411 semantics; addbefore now affects only the unsafe part of step_tac
  7412 etc.; this affects addss/auto_tac/force_tac, so EXISTING PROOFS MAY
  7413 FAIL, but proofs should be fixable easily, e.g. by replacing Auto_tac
  7414 by Force_tac;
  7415 
  7416 * Classical reasoner: setwrapper to setWrapper and compwrapper to
  7417 compWrapper; added safe wrapper (and access functions for it);
  7418 
  7419 * HOL/split_all_tac is now much faster and fails if there is nothing
  7420 to split.  Some EXISTING PROOFS MAY REQUIRE ADAPTION because the order
  7421 and the names of the automatically generated variables have changed.
  7422 split_all_tac has moved within claset() from unsafe wrappers to safe
  7423 wrappers, which means that !!-bound variables are split much more
  7424 aggressively, and safe_tac and clarify_tac now split such variables.
  7425 If this splitting is not appropriate, use delSWrapper "split_all_tac".
  7426 Note: the same holds for record_split_tac, which does the job of
  7427 split_all_tac for record fields.
  7428 
  7429 * HOL/Simplifier: Rewrite rules for case distinctions can now be added
  7430 permanently to the default simpset using Addsplits just like
  7431 Addsimps. They can be removed via Delsplits just like
  7432 Delsimps. Lower-case versions are also available.
  7433 
  7434 * HOL/Simplifier: The rule split_if is now part of the default
  7435 simpset. This means that the simplifier will eliminate all occurrences
  7436 of if-then-else in the conclusion of a goal. To prevent this, you can
  7437 either remove split_if completely from the default simpset by
  7438 `Delsplits [split_if]' or remove it in a specific call of the
  7439 simplifier using `... delsplits [split_if]'.  You can also add/delete
  7440 other case splitting rules to/from the default simpset: every datatype
  7441 generates suitable rules `split_t_case' and `split_t_case_asm' (where
  7442 t is the name of the datatype).
  7443 
  7444 * Classical reasoner / Simplifier combination: new force_tac (and
  7445 derivatives Force_tac, force) combines rewriting and classical
  7446 reasoning (and whatever other tools) similarly to auto_tac, but is
  7447 aimed to solve the given subgoal completely.
  7448 
  7449 
  7450 *** General ***
  7451 
  7452 * new top-level commands `Goal' and `Goalw' that improve upon `goal'
  7453 and `goalw': the theory is no longer needed as an explicit argument -
  7454 the current theory context is used; assumptions are no longer returned
  7455 at the ML-level unless one of them starts with ==> or !!; it is
  7456 recommended to convert to these new commands using isatool fixgoal
  7457 (backup your sources first!);
  7458 
  7459 * new top-level commands 'thm' and 'thms' for retrieving theorems from
  7460 the current theory context, and 'theory' to lookup stored theories;
  7461 
  7462 * new theory section 'locale' for declaring constants, assumptions and
  7463 definitions that have local scope;
  7464 
  7465 * new theory section 'nonterminals' for purely syntactic types;
  7466 
  7467 * new theory section 'setup' for generic ML setup functions
  7468 (e.g. package initialization);
  7469 
  7470 * the distribution now includes Isabelle icons: see
  7471 lib/logo/isabelle-{small,tiny}.xpm;
  7472 
  7473 * isatool install - install binaries with absolute references to
  7474 ISABELLE_HOME/bin;
  7475 
  7476 * isatool logo -- create instances of the Isabelle logo (as EPS);
  7477 
  7478 * print mode 'emacs' reserved for Isamode;
  7479 
  7480 * support multiple print (ast) translations per constant name;
  7481 
  7482 * theorems involving oracles are now printed with a suffixed [!];
  7483 
  7484 
  7485 *** HOL ***
  7486 
  7487 * there is now a tutorial on Isabelle/HOL (do 'isatool doc tutorial');
  7488 
  7489 * HOL/inductive package reorganized and improved: now supports mutual
  7490 definitions such as
  7491 
  7492   inductive EVEN ODD
  7493     intrs
  7494       null "0 : EVEN"
  7495       oddI "n : EVEN ==> Suc n : ODD"
  7496       evenI "n : ODD ==> Suc n : EVEN"
  7497 
  7498 new theorem list "elims" contains an elimination rule for each of the
  7499 recursive sets; inductive definitions now handle disjunctive premises
  7500 correctly (also ZF);
  7501 
  7502 INCOMPATIBILITIES: requires Inductive as an ancestor; component
  7503 "mutual_induct" no longer exists - the induction rule is always
  7504 contained in "induct";
  7505 
  7506 
  7507 * HOL/datatype package re-implemented and greatly improved: now
  7508 supports mutually recursive datatypes such as
  7509 
  7510   datatype
  7511     'a aexp = IF_THEN_ELSE ('a bexp) ('a aexp) ('a aexp)
  7512             | SUM ('a aexp) ('a aexp)
  7513             | DIFF ('a aexp) ('a aexp)
  7514             | NUM 'a
  7515   and
  7516     'a bexp = LESS ('a aexp) ('a aexp)
  7517             | AND ('a bexp) ('a bexp)
  7518             | OR ('a bexp) ('a bexp)
  7519 
  7520 as well as indirectly recursive datatypes such as
  7521 
  7522   datatype
  7523     ('a, 'b) term = Var 'a
  7524                   | App 'b ((('a, 'b) term) list)
  7525 
  7526 The new tactic  mutual_induct_tac [<var_1>, ..., <var_n>] i  performs
  7527 induction on mutually / indirectly recursive datatypes.
  7528 
  7529 Primrec equations are now stored in theory and can be accessed via
  7530 <function_name>.simps.
  7531 
  7532 INCOMPATIBILITIES:
  7533 
  7534   - Theories using datatypes must now have theory Datatype as an
  7535     ancestor.
  7536   - The specific <typename>.induct_tac no longer exists - use the
  7537     generic induct_tac instead.
  7538   - natE has been renamed to nat.exhaust - use exhaust_tac
  7539     instead of res_inst_tac ... natE. Note that the variable
  7540     names in nat.exhaust differ from the names in natE, this
  7541     may cause some "fragile" proofs to fail.
  7542   - The theorems split_<typename>_case and split_<typename>_case_asm
  7543     have been renamed to <typename>.split and <typename>.split_asm.
  7544   - Since default sorts of type variables are now handled correctly,
  7545     some datatype definitions may have to be annotated with explicit
  7546     sort constraints.
  7547   - Primrec definitions no longer require function name and type
  7548     of recursive argument.
  7549 
  7550 Consider using isatool fixdatatype to adapt your theories and proof
  7551 scripts to the new package (backup your sources first!).
  7552 
  7553 
  7554 * HOL/record package: considerably improved implementation; now
  7555 includes concrete syntax for record types, terms, updates; theorems
  7556 for surjective pairing and splitting !!-bound record variables; proof
  7557 support is as follows:
  7558 
  7559   1) standard conversions (selectors or updates applied to record
  7560 constructor terms) are part of the standard simpset;
  7561 
  7562   2) inject equations of the form ((x, y) = (x', y')) == x=x' & y=y' are
  7563 made part of standard simpset and claset via addIffs;
  7564 
  7565   3) a tactic for record field splitting (record_split_tac) is part of
  7566 the standard claset (addSWrapper);
  7567 
  7568 To get a better idea about these rules you may retrieve them via
  7569 something like 'thms "foo.simps"' or 'thms "foo.iffs"', where "foo" is
  7570 the name of your record type.
  7571 
  7572 The split tactic 3) conceptually simplifies by the following rule:
  7573 
  7574   "(!!x. PROP ?P x) == (!!a b. PROP ?P (a, b))"
  7575 
  7576 Thus any record variable that is bound by meta-all will automatically
  7577 blow up into some record constructor term, consequently the
  7578 simplifications of 1), 2) apply.  Thus force_tac, auto_tac etc. shall
  7579 solve record problems automatically.
  7580 
  7581 
  7582 * reorganized the main HOL image: HOL/Integ and String loaded by
  7583 default; theory Main includes everything;
  7584 
  7585 * automatic simplification of integer sums and comparisons, using cancellation;
  7586 
  7587 * added option_map_eq_Some and not_Some_eq to the default simpset and claset;
  7588 
  7589 * added disj_not1 = "(~P | Q) = (P --> Q)" to the default simpset;
  7590 
  7591 * many new identities for unions, intersections, set difference, etc.;
  7592 
  7593 * expand_if, expand_split, expand_sum_case and expand_nat_case are now
  7594 called split_if, split_split, split_sum_case and split_nat_case (to go
  7595 with add/delsplits);
  7596 
  7597 * HOL/Prod introduces simplification procedure unit_eq_proc rewriting
  7598 (?x::unit) = (); this is made part of the default simpset, which COULD
  7599 MAKE EXISTING PROOFS FAIL under rare circumstances (consider
  7600 'Delsimprocs [unit_eq_proc];' as last resort); also note that
  7601 unit_abs_eta_conv is added in order to counter the effect of
  7602 unit_eq_proc on (%u::unit. f u), replacing it by f rather than by
  7603 %u.f();
  7604 
  7605 * HOL/Fun INCOMPATIBILITY: `inj_onto' is now called `inj_on' (which
  7606 makes more sense);
  7607 
  7608 * HOL/Set INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  7609   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  7610   disjointness reasoning but breaking a few old proofs.
  7611 
  7612 * HOL/Relation INCOMPATIBILITY: renamed the relational operator r^-1
  7613 to 'converse' from 'inverse' (for compatibility with ZF and some
  7614 literature);
  7615 
  7616 * HOL/recdef can now declare non-recursive functions, with {} supplied as
  7617 the well-founded relation;
  7618 
  7619 * HOL/Set INCOMPATIBILITY: the complement of set A is now written -A instead of
  7620     Compl A.  The "Compl" syntax remains available as input syntax for this
  7621     release ONLY.
  7622 
  7623 * HOL/Update: new theory of function updates:
  7624     f(a:=b) == %x. if x=a then b else f x
  7625 may also be iterated as in f(a:=b,c:=d,...);
  7626 
  7627 * HOL/Vimage: new theory for inverse image of a function, syntax f-``B;
  7628 
  7629 * HOL/List:
  7630   - new function list_update written xs[i:=v] that updates the i-th
  7631     list position. May also be iterated as in xs[i:=a,j:=b,...].
  7632   - new function `upt' written [i..j(] which generates the list
  7633     [i,i+1,...,j-1], i.e. the upper bound is excluded. To include the upper
  7634     bound write [i..j], which is a shorthand for [i..j+1(].
  7635   - new lexicographic orderings and corresponding wellfoundedness theorems.
  7636 
  7637 * HOL/Arith:
  7638   - removed 'pred' (predecessor) function;
  7639   - generalized some theorems about n-1;
  7640   - many new laws about "div" and "mod";
  7641   - new laws about greatest common divisors (see theory ex/Primes);
  7642 
  7643 * HOL/Relation: renamed the relational operator r^-1 "converse"
  7644 instead of "inverse";
  7645 
  7646 * HOL/Induct/Multiset: a theory of multisets, including the wellfoundedness
  7647   of the multiset ordering;
  7648 
  7649 * directory HOL/Real: a construction of the reals using Dedekind cuts
  7650   (not included by default);
  7651 
  7652 * directory HOL/UNITY: Chandy and Misra's UNITY formalism;
  7653 
  7654 * directory HOL/Hoare: a new version of Hoare logic which permits many-sorted
  7655   programs, i.e. different program variables may have different types.
  7656 
  7657 * calling (stac rew i) now fails if "rew" has no effect on the goal
  7658   [previously, this check worked only if the rewrite rule was unconditional]
  7659   Now rew can involve either definitions or equalities (either == or =).
  7660 
  7661 
  7662 *** ZF ***
  7663 
  7664 * theory Main includes everything; INCOMPATIBILITY: theory ZF.thy contains
  7665   only the theorems proved on ZF.ML;
  7666 
  7667 * ZF INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  7668   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  7669   disjointness reasoning but breaking a few old proofs.
  7670 
  7671 * ZF/Update: new theory of function updates
  7672     with default rewrite rule  f(x:=y) ` z = if(z=x, y, f`z)
  7673   may also be iterated as in f(a:=b,c:=d,...);
  7674 
  7675 * in  let x=t in u(x), neither t nor u(x) has to be an FOL term.
  7676 
  7677 * calling (stac rew i) now fails if "rew" has no effect on the goal
  7678   [previously, this check worked only if the rewrite rule was unconditional]
  7679   Now rew can involve either definitions or equalities (either == or =).
  7680 
  7681 * case_tac provided for compatibility with HOL
  7682     (like the old excluded_middle_tac, but with subgoals swapped)
  7683 
  7684 
  7685 *** Internal programming interfaces ***
  7686 
  7687 * Pure: several new basic modules made available for general use, see
  7688 also src/Pure/README;
  7689 
  7690 * improved the theory data mechanism to support encapsulation (data
  7691 kind name replaced by private Object.kind, acting as authorization
  7692 key); new type-safe user interface via functor TheoryDataFun; generic
  7693 print_data function becomes basically useless;
  7694 
  7695 * removed global_names compatibility flag -- all theory declarations
  7696 are qualified by default;
  7697 
  7698 * module Pure/Syntax now offers quote / antiquote translation
  7699 functions (useful for Hoare logic etc. with implicit dependencies);
  7700 see HOL/ex/Antiquote for an example use;
  7701 
  7702 * Simplifier now offers conversions (asm_)(full_)rewrite: simpset ->
  7703 cterm -> thm;
  7704 
  7705 * new tactical CHANGED_GOAL for checking that a tactic modifies a
  7706 subgoal;
  7707 
  7708 * Display.print_goals function moved to Locale.print_goals;
  7709 
  7710 * standard print function for goals supports current_goals_markers
  7711 variable for marking begin of proof, end of proof, start of goal; the
  7712 default is ("", "", ""); setting current_goals_markers := ("<proof>",
  7713 "</proof>", "<goal>") causes SGML like tagged proof state printing,
  7714 for example;
  7715 
  7716 
  7717 
  7718 New in Isabelle98 (January 1998)
  7719 --------------------------------
  7720 
  7721 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  7722 
  7723 * changed lexical syntax of terms / types: dots made part of long
  7724 identifiers, e.g. "%x.x" no longer possible, should be "%x. x";
  7725 
  7726 * simpset (and claset) reference variable replaced by functions
  7727 simpset / simpset_ref;
  7728 
  7729 * no longer supports theory aliases (via merge) and non-trivial
  7730 implicit merge of thms' signatures;
  7731 
  7732 * most internal names of constants changed due to qualified names;
  7733 
  7734 * changed Pure/Sequence interface (see Pure/seq.ML);
  7735 
  7736 
  7737 *** General Changes ***
  7738 
  7739 * hierachically structured name spaces (for consts, types, axms, thms
  7740 etc.); new lexical class 'longid' (e.g. Foo.bar.x) may render much of
  7741 old input syntactically incorrect (e.g. "%x.x"); COMPATIBILITY:
  7742 isatool fixdots ensures space after dots (e.g. "%x. x"); set
  7743 long_names for fully qualified output names; NOTE: ML programs
  7744 (special tactics, packages etc.) referring to internal names may have
  7745 to be adapted to cope with fully qualified names; in case of severe
  7746 backward campatibility problems try setting 'global_names' at compile
  7747 time to have enrything declared within a flat name space; one may also
  7748 fine tune name declarations in theories via the 'global' and 'local'
  7749 section;
  7750 
  7751 * reimplemented the implicit simpset and claset using the new anytype
  7752 data filed in signatures; references simpset:simpset ref etc. are
  7753 replaced by functions simpset:unit->simpset and
  7754 simpset_ref:unit->simpset ref; COMPATIBILITY: use isatool fixclasimp
  7755 to patch your ML files accordingly;
  7756 
  7757 * HTML output now includes theory graph data for display with Java
  7758 applet or isatool browser; data generated automatically via isatool
  7759 usedir (see -i option, ISABELLE_USEDIR_OPTIONS);
  7760 
  7761 * defs may now be conditional; improved rewrite_goals_tac to handle
  7762 conditional equations;
  7763 
  7764 * defs now admits additional type arguments, using TYPE('a) syntax;
  7765 
  7766 * theory aliases via merge (e.g. M=A+B+C) no longer supported, always
  7767 creates a new theory node; implicit merge of thms' signatures is
  7768 restricted to 'trivial' ones; COMPATIBILITY: one may have to use
  7769 transfer:theory->thm->thm in (rare) cases;
  7770 
  7771 * improved handling of draft signatures / theories; draft thms (and
  7772 ctyps, cterms) are automatically promoted to real ones;
  7773 
  7774 * slightly changed interfaces for oracles: admit many per theory, named
  7775 (e.g. oracle foo = mlfun), additional name argument for invoke_oracle;
  7776 
  7777 * print_goals: optional output of const types (set show_consts and
  7778 show_types);
  7779 
  7780 * improved output of warnings (###) and errors (***);
  7781 
  7782 * subgoal_tac displays a warning if the new subgoal has type variables;
  7783 
  7784 * removed old README and Makefiles;
  7785 
  7786 * replaced print_goals_ref hook by print_current_goals_fn and result_error_fn;
  7787 
  7788 * removed obsolete init_pps and init_database;
  7789 
  7790 * deleted the obsolete tactical STATE, which was declared by
  7791     fun STATE tacfun st = tacfun st st;
  7792 
  7793 * cd and use now support path variables, e.g. $ISABELLE_HOME, or ~
  7794 (which abbreviates $HOME);
  7795 
  7796 * changed Pure/Sequence interface (see Pure/seq.ML); COMPATIBILITY:
  7797 use isatool fixseq to adapt your ML programs (this works for fully
  7798 qualified references to the Sequence structure only!);
  7799 
  7800 * use_thy no longer requires writable current directory; it always
  7801 reloads .ML *and* .thy file, if either one is out of date;
  7802 
  7803 
  7804 *** Classical Reasoner ***
  7805 
  7806 * Clarify_tac, clarify_tac, clarify_step_tac, Clarify_step_tac: new
  7807 tactics that use classical reasoning to simplify a subgoal without
  7808 splitting it into several subgoals;
  7809 
  7810 * Safe_tac: like safe_tac but uses the default claset;
  7811 
  7812 
  7813 *** Simplifier ***
  7814 
  7815 * added simplification meta rules:
  7816     (asm_)(full_)simplify: simpset -> thm -> thm;
  7817 
  7818 * simplifier.ML no longer part of Pure -- has to be loaded by object
  7819 logics (again);
  7820 
  7821 * added prems argument to simplification procedures;
  7822 
  7823 * HOL, FOL, ZF: added infix function `addsplits':
  7824   instead of `<simpset> setloop (split_tac <thms>)'
  7825   you can simply write `<simpset> addsplits <thms>'
  7826 
  7827 
  7828 *** Syntax ***
  7829 
  7830 * TYPE('a) syntax for type reflection terms;
  7831 
  7832 * no longer handles consts with name "" -- declare as 'syntax' instead;
  7833 
  7834 * pretty printer: changed order of mixfix annotation preference (again!);
  7835 
  7836 * Pure: fixed idt/idts vs. pttrn/pttrns syntactic categories;
  7837 
  7838 
  7839 *** HOL ***
  7840 
  7841 * HOL: there is a new splitter `split_asm_tac' that can be used e.g.
  7842   with `addloop' of the simplifier to faciliate case splitting in premises.
  7843 
  7844 * HOL/TLA: Stephan Merz's formalization of Lamport's Temporal Logic of Actions;
  7845 
  7846 * HOL/Auth: new protocol proofs including some for the Internet
  7847   protocol TLS;
  7848 
  7849 * HOL/Map: new theory of `maps' a la VDM;
  7850 
  7851 * HOL/simplifier: simplification procedures nat_cancel_sums for
  7852 cancelling out common nat summands from =, <, <= (in)equalities, or
  7853 differences; simplification procedures nat_cancel_factor for
  7854 cancelling common factor from =, <, <= (in)equalities over natural
  7855 sums; nat_cancel contains both kinds of procedures, it is installed by
  7856 default in Arith.thy -- this COULD MAKE EXISTING PROOFS FAIL;
  7857 
  7858 * HOL/simplifier: terms of the form
  7859   `? x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x)'  (or t=x)
  7860   are rewritten to
  7861   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t)',
  7862   and those of the form
  7863   `! x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x) --> R(x)'  (or t=x)
  7864   are rewritten to
  7865   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t) --> R(t)',
  7866 
  7867 * HOL/datatype
  7868   Each datatype `t' now comes with a theorem `split_t_case' of the form
  7869 
  7870   P(t_case f1 ... fn x) =
  7871      ( (!y1 ... ym1. x = C1 y1 ... ym1 --> P(f1 y1 ... ym1)) &
  7872         ...
  7873        (!y1 ... ymn. x = Cn y1 ... ymn --> P(f1 y1 ... ymn))
  7874      )
  7875 
  7876   and a theorem `split_t_case_asm' of the form
  7877 
  7878   P(t_case f1 ... fn x) =
  7879     ~( (? y1 ... ym1. x = C1 y1 ... ym1 & ~P(f1 y1 ... ym1)) |
  7880         ...
  7881        (? y1 ... ymn. x = Cn y1 ... ymn & ~P(f1 y1 ... ymn))
  7882      )
  7883   which can be added to a simpset via `addsplits'. The existing theorems
  7884   expand_list_case and expand_option_case have been renamed to
  7885   split_list_case and split_option_case.
  7886 
  7887 * HOL/Arithmetic:
  7888   - `pred n' is automatically converted to `n-1'.
  7889     Users are strongly encouraged not to use `pred' any longer,
  7890     because it will disappear altogether at some point.
  7891   - Users are strongly encouraged to write "0 < n" rather than
  7892     "n ~= 0". Theorems and proof tools have been modified towards this
  7893     `standard'.
  7894 
  7895 * HOL/Lists:
  7896   the function "set_of_list" has been renamed "set" (and its theorems too);
  7897   the function "nth" now takes its arguments in the reverse order and
  7898   has acquired the infix notation "!" as in "xs!n".
  7899 
  7900 * HOL/Set: UNIV is now a constant and is no longer translated to Compl{};
  7901 
  7902 * HOL/Set: The operator (UN x.B x) now abbreviates (UN x:UNIV. B x) and its
  7903   specialist theorems (like UN1_I) are gone.  Similarly for (INT x.B x);
  7904 
  7905 * HOL/record: extensible records with schematic structural subtyping
  7906 (single inheritance); EXPERIMENTAL version demonstrating the encoding,
  7907 still lacks various theorems and concrete record syntax;
  7908 
  7909 
  7910 *** HOLCF ***
  7911 
  7912 * removed "axioms" and "generated by" sections;
  7913 
  7914 * replaced "ops" section by extended "consts" section, which is capable of
  7915   handling the continuous function space "->" directly;
  7916 
  7917 * domain package:
  7918   . proves theorems immediately and stores them in the theory,
  7919   . creates hierachical name space,
  7920   . now uses normal mixfix annotations (instead of cinfix...),
  7921   . minor changes to some names and values (for consistency),
  7922   . e.g. cases -> casedist, dists_eq -> dist_eqs, [take_lemma] -> take_lemmas,
  7923   . separator between mutual domain defs: changed "," to "and",
  7924   . improved handling of sort constraints;  now they have to
  7925     appear on the left-hand side of the equations only;
  7926 
  7927 * fixed LAM <x,y,zs>.b syntax;
  7928 
  7929 * added extended adm_tac to simplifier in HOLCF -- can now discharge
  7930 adm (%x. P (t x)), where P is chainfinite and t continuous;
  7931 
  7932 
  7933 *** FOL and ZF ***
  7934 
  7935 * FOL: there is a new splitter `split_asm_tac' that can be used e.g.
  7936   with `addloop' of the simplifier to faciliate case splitting in premises.
  7937 
  7938 * qed_spec_mp, qed_goal_spec_mp, qed_goalw_spec_mp are available, as
  7939 in HOL, they strip ALL and --> from proved theorems;
  7940 
  7941 
  7942 
  7943 New in Isabelle94-8 (May 1997)
  7944 ------------------------------
  7945 
  7946 *** General Changes ***
  7947 
  7948 * new utilities to build / run / maintain Isabelle etc. (in parts
  7949 still somewhat experimental); old Makefiles etc. still functional;
  7950 
  7951 * new 'Isabelle System Manual';
  7952 
  7953 * INSTALL text, together with ./configure and ./build scripts;
  7954 
  7955 * reimplemented type inference for greater efficiency, better error
  7956 messages and clean internal interface;
  7957 
  7958 * prlim command for dealing with lots of subgoals (an easier way of
  7959 setting goals_limit);
  7960 
  7961 
  7962 *** Syntax ***
  7963 
  7964 * supports alternative (named) syntax tables (parser and pretty
  7965 printer); internal interface is provided by add_modesyntax(_i);
  7966 
  7967 * Pure, FOL, ZF, HOL, HOLCF now support symbolic input and output; to
  7968 be used in conjunction with the Isabelle symbol font; uses the
  7969 "symbols" syntax table;
  7970 
  7971 * added token_translation interface (may translate name tokens in
  7972 arbitrary ways, dependent on their type (free, bound, tfree, ...) and
  7973 the current print_mode); IMPORTANT: user print translation functions
  7974 are responsible for marking newly introduced bounds
  7975 (Syntax.mark_boundT);
  7976 
  7977 * token translations for modes "xterm" and "xterm_color" that display
  7978 names in bold, underline etc. or colors (which requires a color
  7979 version of xterm);
  7980 
  7981 * infixes may now be declared with names independent of their syntax;
  7982 
  7983 * added typed_print_translation (like print_translation, but may
  7984 access type of constant);
  7985 
  7986 
  7987 *** Classical Reasoner ***
  7988 
  7989 Blast_tac: a new tactic!  It is often more powerful than fast_tac, but has
  7990 some limitations.  Blast_tac...
  7991   + ignores addss, addbefore, addafter; this restriction is intrinsic
  7992   + ignores elimination rules that don't have the correct format
  7993         (the conclusion MUST be a formula variable)
  7994   + ignores types, which can make HOL proofs fail
  7995   + rules must not require higher-order unification, e.g. apply_type in ZF
  7996     [message "Function Var's argument not a bound variable" relates to this]
  7997   + its proof strategy is more general but can actually be slower
  7998 
  7999 * substitution with equality assumptions no longer permutes other
  8000 assumptions;
  8001 
  8002 * minor changes in semantics of addafter (now called addaltern); renamed
  8003 setwrapper to setWrapper and compwrapper to compWrapper; added safe wrapper
  8004 (and access functions for it);
  8005 
  8006 * improved combination of classical reasoner and simplifier:
  8007   + functions for handling clasimpsets
  8008   + improvement of addss: now the simplifier is called _after_ the
  8009     safe steps.
  8010   + safe variant of addss called addSss: uses safe simplifications
  8011     _during_ the safe steps. It is more complete as it allows multiple
  8012     instantiations of unknowns (e.g. with slow_tac).
  8013 
  8014 *** Simplifier ***
  8015 
  8016 * added interface for simplification procedures (functions that
  8017 produce *proven* rewrite rules on the fly, depending on current
  8018 redex);
  8019 
  8020 * ordering on terms as parameter (used for ordered rewriting);
  8021 
  8022 * new functions delcongs, deleqcongs, and Delcongs. richer rep_ss;
  8023 
  8024 * the solver is now split into a safe and an unsafe part.
  8025 This should be invisible for the normal user, except that the
  8026 functions setsolver and addsolver have been renamed to setSolver and
  8027 addSolver; added safe_asm_full_simp_tac;
  8028 
  8029 
  8030 *** HOL ***
  8031 
  8032 * a generic induction tactic `induct_tac' which works for all datatypes and
  8033 also for type `nat';
  8034 
  8035 * a generic case distinction tactic `exhaust_tac' which works for all
  8036 datatypes and also for type `nat';
  8037 
  8038 * each datatype comes with a function `size';
  8039 
  8040 * patterns in case expressions allow tuple patterns as arguments to
  8041 constructors, for example `case x of [] => ... | (x,y,z)#ps => ...';
  8042 
  8043 * primrec now also works with type nat;
  8044 
  8045 * recdef: a new declaration form, allows general recursive functions to be
  8046 defined in theory files.  See HOL/ex/Fib, HOL/ex/Primes, HOL/Subst/Unify.
  8047 
  8048 * the constant for negation has been renamed from "not" to "Not" to
  8049 harmonize with FOL, ZF, LK, etc.;
  8050 
  8051 * HOL/ex/LFilter theory of a corecursive "filter" functional for
  8052 infinite lists;
  8053 
  8054 * HOL/Modelcheck demonstrates invocation of model checker oracle;
  8055 
  8056 * HOL/ex/Ring.thy declares cring_simp, which solves equational
  8057 problems in commutative rings, using axiomatic type classes for + and *;
  8058 
  8059 * more examples in HOL/MiniML and HOL/Auth;
  8060 
  8061 * more default rewrite rules for quantifiers, union/intersection;
  8062 
  8063 * a new constant `arbitrary == @x.False';
  8064 
  8065 * HOLCF/IOA replaces old HOL/IOA;
  8066 
  8067 * HOLCF changes: derived all rules and arities
  8068   + axiomatic type classes instead of classes
  8069   + typedef instead of faking type definitions
  8070   + eliminated the internal constants less_fun, less_cfun, UU_fun, UU_cfun etc.
  8071   + new axclasses cpo, chfin, flat with flat < chfin < pcpo < cpo < po
  8072   + eliminated the types void, one, tr
  8073   + use unit lift and bool lift (with translations) instead of one and tr
  8074   + eliminated blift from Lift3.thy (use Def instead of blift)
  8075   all eliminated rules are derived as theorems --> no visible changes ;
  8076 
  8077 
  8078 *** ZF ***
  8079 
  8080 * ZF now has Fast_tac, Simp_tac and Auto_tac.  Union_iff is a now a default
  8081 rewrite rule; this may affect some proofs.  eq_cs is gone but can be put back
  8082 as ZF_cs addSIs [equalityI];
  8083 
  8084 
  8085 
  8086 New in Isabelle94-7 (November 96)
  8087 ---------------------------------
  8088 
  8089 * allowing negative levels (as offsets) in prlev and choplev;
  8090 
  8091 * super-linear speedup for large simplifications;
  8092 
  8093 * FOL, ZF and HOL now use miniscoping: rewriting pushes
  8094 quantifications in as far as possible (COULD MAKE EXISTING PROOFS
  8095 FAIL); can suppress it using the command Delsimps (ex_simps @
  8096 all_simps); De Morgan laws are also now included, by default;
  8097 
  8098 * improved printing of ==>  :  ~:
  8099 
  8100 * new object-logic "Sequents" adds linear logic, while replacing LK
  8101 and Modal (thanks to Sara Kalvala);
  8102 
  8103 * HOL/Auth: correctness proofs for authentication protocols;
  8104 
  8105 * HOL: new auto_tac combines rewriting and classical reasoning (many
  8106 examples on HOL/Auth);
  8107 
  8108 * HOL: new command AddIffs for declaring theorems of the form P=Q to
  8109 the rewriter and classical reasoner simultaneously;
  8110 
  8111 * function uresult no longer returns theorems in "standard" format;
  8112 regain previous version by: val uresult = standard o uresult;
  8113 
  8114 
  8115 
  8116 New in Isabelle94-6
  8117 -------------------
  8118 
  8119 * oracles -- these establish an interface between Isabelle and trusted
  8120 external reasoners, which may deliver results as theorems;
  8121 
  8122 * proof objects (in particular record all uses of oracles);
  8123 
  8124 * Simp_tac, Fast_tac, etc. that refer to implicit simpset / claset;
  8125 
  8126 * "constdefs" section in theory files;
  8127 
  8128 * "primrec" section (HOL) no longer requires names;
  8129 
  8130 * internal type "tactic" now simply "thm -> thm Sequence.seq";
  8131 
  8132 
  8133 
  8134 New in Isabelle94-5
  8135 -------------------
  8136 
  8137 * reduced space requirements;
  8138 
  8139 * automatic HTML generation from theories;
  8140 
  8141 * theory files no longer require "..." (quotes) around most types;
  8142 
  8143 * new examples, including two proofs of the Church-Rosser theorem;
  8144 
  8145 * non-curried (1994) version of HOL is no longer distributed;
  8146 
  8147 
  8148 
  8149 New in Isabelle94-4
  8150 -------------------
  8151 
  8152 * greatly reduced space requirements;
  8153 
  8154 * theory files (.thy) no longer require \...\ escapes at line breaks;
  8155 
  8156 * searchable theorem database (see the section "Retrieving theorems" on
  8157 page 8 of the Reference Manual);
  8158 
  8159 * new examples, including Grabczewski's monumental case study of the
  8160 Axiom of Choice;
  8161 
  8162 * The previous version of HOL renamed to Old_HOL;
  8163 
  8164 * The new version of HOL (previously called CHOL) uses a curried syntax
  8165 for functions.  Application looks like f a b instead of f(a,b);
  8166 
  8167 * Mutually recursive inductive definitions finally work in HOL;
  8168 
  8169 * In ZF, pattern-matching on tuples is now available in all abstractions and
  8170 translates to the operator "split";
  8171 
  8172 
  8173 
  8174 New in Isabelle94-3
  8175 -------------------
  8176 
  8177 * new infix operator, addss, allowing the classical reasoner to
  8178 perform simplification at each step of its search.  Example:
  8179         fast_tac (cs addss ss)
  8180 
  8181 * a new logic, CHOL, the same as HOL, but with a curried syntax
  8182 for functions.  Application looks like f a b instead of f(a,b).  Also pairs
  8183 look like (a,b) instead of <a,b>;
  8184 
  8185 * PLEASE NOTE: CHOL will eventually replace HOL!
  8186 
  8187 * In CHOL, pattern-matching on tuples is now available in all abstractions.
  8188 It translates to the operator "split".  A new theory of integers is available;
  8189 
  8190 * In ZF, integer numerals now denote two's-complement binary integers.
  8191 Arithmetic operations can be performed by rewriting.  See ZF/ex/Bin.ML;
  8192 
  8193 * Many new examples: I/O automata, Church-Rosser theorem, equivalents
  8194 of the Axiom of Choice;
  8195 
  8196 
  8197 
  8198 New in Isabelle94-2
  8199 -------------------
  8200 
  8201 * Significantly faster resolution;
  8202 
  8203 * the different sections in a .thy file can now be mixed and repeated
  8204 freely;
  8205 
  8206 * Database of theorems for FOL, HOL and ZF.  New
  8207 commands including qed, qed_goal and bind_thm store theorems in the database.
  8208 
  8209 * Simple database queries: return a named theorem (get_thm) or all theorems of
  8210 a given theory (thms_of), or find out what theory a theorem was proved in
  8211 (theory_of_thm);
  8212 
  8213 * Bugs fixed in the inductive definition and datatype packages;
  8214 
  8215 * The classical reasoner provides deepen_tac and depth_tac, making FOL_dup_cs
  8216 and HOL_dup_cs obsolete;
  8217 
  8218 * Syntactic ambiguities caused by the new treatment of syntax in Isabelle94-1
  8219 have been removed;
  8220 
  8221 * Simpler definition of function space in ZF;
  8222 
  8223 * new results about cardinal and ordinal arithmetic in ZF;
  8224 
  8225 * 'subtype' facility in HOL for introducing new types as subsets of existing
  8226 types;
  8227 
  8228 :mode=text:wrap=hard:maxLineLen=72: