NEWS
author wenzelm
Sun May 15 18:00:08 2011 +0200 (2011-05-15)
changeset 42815 61668e617a3b
parent 42809 5b45125b15ba
child 42843 0e594ba0b324
permissions -rw-r--r--
NEWS (cf. 4e8483cc2cc5);
     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 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
    62 
    63 * Finite_Set.thy: locale fun_left_comm uses point-free characterisation;
    64 interpretation proofs may need adjustment.  INCOMPATIBILITY.
    65 
    66 * Nitpick:
    67   - Added "need" and "total_consts" options.
    68   - Reintroduced "show_skolems" option by popular demand.
    69   - Renamed attribute: nitpick_def ~> nitpick_unfold.
    70     INCOMPATIBILITY.
    71 
    72 * Sledgehammer:
    73   - sledgehammer available_provers ~> sledgehammer supported_provers
    74     INCOMPATIBILITY.
    75   - Added support for SNARK and ToFoF-E on SystemOnTPTP and for simply typed
    76     TPTP problems (TFF).
    77   - Added "type_sys", "max_mono_iters", and "max_new_mono_instances" options.
    78 
    79 * "try":
    80   - Added "simp:", "intro:", and "elim:" options.
    81 
    82 * Quickcheck:
    83   - Added "eval" option to evaluate terms for the found counterexample
    84     (currently only supported by the default (exhaustive) tester)
    85   - Added post-processing of terms to obtain readable counterexamples
    86     (currently only supported by the default (exhaustive) tester)
    87 
    88 * Function package: discontinued option "tailrec".
    89 INCOMPATIBILITY. Use partial_function instead.
    90 
    91 * HOL-Probability:
    92   - Caratheodory's extension lemma is now proved for ring_of_sets.
    93   - Infinite products of probability measures are now available.
    94   - Use extended reals instead of positive extended reals.
    95     INCOMPATIBILITY.
    96 
    97 
    98 *** Document preparation ***
    99 
   100 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
   101 isar-ref manual.
   102 
   103 * Localized \isabellestyle switch can be used within blocks or groups
   104 like this:
   105 
   106   \isabellestyle{it}  %preferred default
   107   {\isabellestylett @{text "typewriter stuff"}}
   108 
   109 * New term style "isub" as ad-hoc conversion of variables x1, y23 into
   110 subscripted form x\<^isub>1, y\<^isub>2\<^isub>3.
   111 
   112 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
   113 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
   114 
   115 
   116 *** ML ***
   117 
   118 * Structure Proof_Context follows standard naming scheme.  Old
   119 ProofContext is still available for some time as legacy alias.
   120 
   121 * Structure Timing provides various operations for timing; supersedes
   122 former start_timing/end_timing etc.
   123 
   124 * Path.print is the official way to show file-system paths to users
   125 (including quotes etc.).
   126 
   127 * Inner syntax: identifiers in parse trees of generic categories
   128 "logic", "aprop", "idt" etc. carry position information (disguised as
   129 type constraints).  Occasional INCOMPATIBILITY with non-compliant
   130 translations that choke on unexpected type constraints.  Positions can
   131 be stripped in ML translations via Syntax.strip_positions /
   132 Syntax.strip_positions_ast, or via the syntax constant
   133 "_strip_positions" within parse trees.  As last resort, positions can
   134 be disabled via the configuration option Syntax.positions, which is
   135 called "syntax_positions" in Isar attribute syntax.
   136 
   137 * Discontinued special status of various ML structures that contribute
   138 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
   139 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
   140 refer directly to Ast.Constant, Lexicon.is_identifier,
   141 Syntax_Trans.mk_binder_tr etc.
   142 
   143 * Typed print translation: discontinued show_sorts argument, which is
   144 already available via context of "advanced" translation.
   145 
   146 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
   147 goal states; body tactic needs to address all subgoals uniformly.
   148 
   149 * Slightly more special eq_list/eq_set, with shortcut involving
   150 pointer equality (assumes that eq relation is reflexive).
   151 
   152 * Classical tactics use proper Proof.context instead of historic types
   153 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
   154 operate directly on Proof.context.  Raw type claset retains its use as
   155 snapshot of the classical context, which can be recovered via
   156 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
   157 INCOMPATIBILITY, classical tactics and derived proof methods require
   158 proper Proof.context.
   159 
   160 
   161 
   162 New in Isabelle2011 (January 2011)
   163 ----------------------------------
   164 
   165 *** General ***
   166 
   167 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
   168 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
   169 useful tooltips and hyperlinks produced from its static analysis.  The
   170 bundled component provides an executable Isabelle tool that can be run
   171 like this:
   172 
   173   Isabelle2011/bin/isabelle jedit
   174 
   175 * Significantly improved Isabelle/Isar implementation manual.
   176 
   177 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
   178 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
   179 while the default heap location within that directory lacks that extra
   180 suffix.  This isolates multiple Isabelle installations from each
   181 other, avoiding problems with old settings in new versions.
   182 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
   183 
   184 * Source files are always encoded as UTF-8, instead of old-fashioned
   185 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   186 the following package declarations:
   187 
   188   \usepackage[utf8]{inputenc}
   189   \usepackage{textcomp}
   190 
   191 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   192 a Unicode character is treated as a single symbol, not a sequence of
   193 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   194 contain symbols without further backslash escapes, Unicode can now be
   195 used here as well.  Recall that Symbol.explode in ML provides a
   196 consistent view on symbols, while raw explode (or String.explode)
   197 merely give a byte-oriented representation.
   198 
   199 * Theory loader: source files are primarily located via the master
   200 directory of each theory node (where the .thy file itself resides).
   201 The global load path is still partially available as legacy feature.
   202 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   203 explicit paths, relatively to the theory.
   204 
   205 * Special treatment of ML file names has been discontinued.
   206 Historically, optional extensions .ML or .sml were added on demand --
   207 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   208 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   209 
   210 * Various options that affect pretty printing etc. are now properly
   211 handled within the context via configuration options, instead of
   212 unsynchronized references or print modes.  There are both ML Config.T
   213 entities and Isar declaration attributes to access these.
   214 
   215   ML (Config.T)                 Isar (attribute)
   216 
   217   eta_contract                  eta_contract
   218   show_brackets                 show_brackets
   219   show_sorts                    show_sorts
   220   show_types                    show_types
   221   show_question_marks           show_question_marks
   222   show_consts                   show_consts
   223   show_abbrevs                  show_abbrevs
   224 
   225   Syntax.ast_trace              syntax_ast_trace
   226   Syntax.ast_stat               syntax_ast_stat
   227   Syntax.ambiguity_level        syntax_ambiguity_level
   228 
   229   Goal_Display.goals_limit      goals_limit
   230   Goal_Display.show_main_goal   show_main_goal
   231 
   232   Method.rule_trace             rule_trace
   233 
   234   Thy_Output.display            thy_output_display
   235   Thy_Output.quotes             thy_output_quotes
   236   Thy_Output.indent             thy_output_indent
   237   Thy_Output.source             thy_output_source
   238   Thy_Output.break              thy_output_break
   239 
   240 Note that corresponding "..._default" references in ML may only be
   241 changed globally at the ROOT session setup, but *not* within a theory.
   242 The option "show_abbrevs" supersedes the former print mode
   243 "no_abbrevs" with inverted meaning.
   244 
   245 * More systematic naming of some configuration options.
   246 INCOMPATIBILITY.
   247 
   248   trace_simp  ~>  simp_trace
   249   debug_simp  ~>  simp_debug
   250 
   251 * Support for real valued configuration options, using simplistic
   252 floating-point notation that coincides with the inner syntax for
   253 float_token.
   254 
   255 * Support for real valued preferences (with approximative PGIP type):
   256 front-ends need to accept "pgint" values in float notation.
   257 INCOMPATIBILITY.
   258 
   259 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   260 DejaVu Sans.
   261 
   262 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   263 
   264 
   265 *** Pure ***
   266 
   267 * Command 'type_synonym' (with single argument) replaces somewhat
   268 outdated 'types', which is still available as legacy feature for some
   269 time.
   270 
   271 * Command 'nonterminal' (with 'and' separated list of arguments)
   272 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   273 
   274 * Command 'notepad' replaces former 'example_proof' for
   275 experimentation in Isar without any result.  INCOMPATIBILITY.
   276 
   277 * Locale interpretation commands 'interpret' and 'sublocale' accept
   278 lists of equations to map definitions in a locale to appropriate
   279 entities in the context of the interpretation.  The 'interpretation'
   280 command already provided this functionality.
   281 
   282 * Diagnostic command 'print_dependencies' prints the locale instances
   283 that would be activated if the specified expression was interpreted in
   284 the current context.  Variant "print_dependencies!" assumes a context
   285 without interpretations.
   286 
   287 * Diagnostic command 'print_interps' prints interpretations in proofs
   288 in addition to interpretations in theories.
   289 
   290 * Discontinued obsolete 'global' and 'local' commands to manipulate
   291 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   292 Sign.root_path and Sign.local_path may be applied directly where this
   293 feature is still required for historical reasons.
   294 
   295 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   296 'definition' instead.
   297 
   298 * The "prems" fact, which refers to the accidental collection of
   299 foundational premises in the context, is now explicitly marked as
   300 legacy feature and will be discontinued soon.  Consider using "assms"
   301 of the head statement or reference facts by explicit names.
   302 
   303 * Document antiquotations @{class} and @{type} print classes and type
   304 constructors.
   305 
   306 * Document antiquotation @{file} checks file/directory entries within
   307 the local file system.
   308 
   309 
   310 *** HOL ***
   311 
   312 * Coercive subtyping: functions can be declared as coercions and type
   313 inference will add them as necessary upon input of a term.  Theory
   314 Complex_Main declares real :: nat => real and real :: int => real as
   315 coercions. A coercion function f is declared like this:
   316 
   317   declare [[coercion f]]
   318 
   319 To lift coercions through type constructors (e.g. from nat => real to
   320 nat list => real list), map functions can be declared, e.g.
   321 
   322   declare [[coercion_map map]]
   323 
   324 Currently coercion inference is activated only in theories including
   325 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   326 the configuration option "coercion_enabled", e.g. it can be enabled in
   327 other theories like this:
   328 
   329   declare [[coercion_enabled]]
   330 
   331 * Command 'partial_function' provides basic support for recursive
   332 function definitions over complete partial orders.  Concrete instances
   333 are provided for i) the option type, ii) tail recursion on arbitrary
   334 types, and iii) the heap monad of Imperative_HOL.  See
   335 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   336 for examples.
   337 
   338 * Function package: f.psimps rules are no longer implicitly declared
   339 as [simp].  INCOMPATIBILITY.
   340 
   341 * Datatype package: theorems generated for executable equality (class
   342 "eq") carry proper names and are treated as default code equations.
   343 
   344 * Inductive package: now offers command 'inductive_simps' to
   345 automatically derive instantiated and simplified equations for
   346 inductive predicates, similar to 'inductive_cases'.
   347 
   348 * Command 'enriched_type' allows to register properties of the
   349 functorial structure of types.
   350 
   351 * Improved infrastructure for term evaluation using code generator
   352 techniques, in particular static evaluation conversions.
   353 
   354 * Code generator: Scala (2.8 or higher) has been added to the target
   355 languages.
   356 
   357 * Code generator: globbing constant expressions "*" and "Theory.*"
   358 have been replaced by the more idiomatic "_" and "Theory._".
   359 INCOMPATIBILITY.
   360 
   361 * Code generator: export_code without explicit file declaration prints
   362 to standard output.  INCOMPATIBILITY.
   363 
   364 * Code generator: do not print function definitions for case
   365 combinators any longer.
   366 
   367 * Code generator: simplification with rules determined with
   368 src/Tools/Code/code_simp.ML and method "code_simp".
   369 
   370 * Code generator for records: more idiomatic representation of record
   371 types.  Warning: records are not covered by ancient SML code
   372 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   373 rep_datatype declaration helps to succeed then:
   374 
   375   record 'a foo = ...
   376   ...
   377   rep_datatype foo_ext ...
   378 
   379 * Records: logical foundation type for records does not carry a
   380 '_type' suffix any longer (obsolete due to authentic syntax).
   381 INCOMPATIBILITY.
   382 
   383 * Quickcheck now by default uses exhaustive testing instead of random
   384 testing.  Random testing can be invoked by "quickcheck [random]",
   385 exhaustive testing by "quickcheck [exhaustive]".
   386 
   387 * Quickcheck instantiates polymorphic types with small finite
   388 datatypes by default. This enables a simple execution mechanism to
   389 handle quantifiers and function equality over the finite datatypes.
   390 
   391 * Quickcheck random generator has been renamed from "code" to
   392 "random".  INCOMPATIBILITY.
   393 
   394 * Quickcheck now has a configurable time limit which is set to 30
   395 seconds by default. This can be changed by adding [timeout = n] to the
   396 quickcheck command. The time limit for Auto Quickcheck is still set
   397 independently.
   398 
   399 * Quickcheck in locales considers interpretations of that locale for
   400 counter example search.
   401 
   402 * Sledgehammer:
   403   - Added "smt" and "remote_smt" provers based on the "smt" proof
   404     method. See the Sledgehammer manual for details ("isabelle doc
   405     sledgehammer").
   406   - Renamed commands:
   407     sledgehammer atp_info ~> sledgehammer running_provers
   408     sledgehammer atp_kill ~> sledgehammer kill_provers
   409     sledgehammer available_atps ~> sledgehammer available_provers
   410     INCOMPATIBILITY.
   411   - Renamed options:
   412     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   413     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   414     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   415     (and "ms" and "min" are no longer supported)
   416     INCOMPATIBILITY.
   417 
   418 * Nitpick:
   419   - Renamed options:
   420     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   421     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   422     INCOMPATIBILITY.
   423   - Added support for partial quotient types.
   424   - Added local versions of the "Nitpick.register_xxx" functions.
   425   - Added "whack" option.
   426   - Allow registration of quotient types as codatatypes.
   427   - Improved "merge_type_vars" option to merge more types.
   428   - Removed unsound "fast_descrs" option.
   429   - Added custom symmetry breaking for datatypes, making it possible to reach
   430     higher cardinalities.
   431   - Prevent the expansion of too large definitions.
   432 
   433 * Proof methods "metis" and "meson" now have configuration options
   434 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   435 to diagnose these tools. E.g.
   436 
   437     using [[metis_trace = true]]
   438 
   439 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   440 manually as command 'solve_direct'.
   441 
   442 * The default SMT solver Z3 must be enabled explicitly (due to
   443 licensing issues) by setting the environment variable
   444 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   445 commercial applications, the SMT solver CVC3 is provided as fall-back;
   446 changing the SMT solver is done via the configuration option
   447 "smt_solver".
   448 
   449 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   450 i.e. "remote_cvc3" and "remote_z3".
   451 
   452 * Added basic SMT support for datatypes, records, and typedefs using
   453 the oracle mode (no proofs).  Direct support of pairs has been dropped
   454 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   455 support for a similar behavior).  Minor INCOMPATIBILITY.
   456 
   457 * Changed SMT configuration options:
   458   - Renamed:
   459     z3_proofs ~> smt_oracle (with inverted meaning)
   460     z3_trace_assms ~> smt_trace_used_facts
   461     INCOMPATIBILITY.
   462   - Added:
   463     smt_verbose
   464     smt_random_seed
   465     smt_datatypes
   466     smt_infer_triggers
   467     smt_monomorph_limit
   468     cvc3_options
   469     remote_cvc3_options
   470     remote_z3_options
   471     yices_options
   472 
   473 * Boogie output files (.b2i files) need to be declared in the theory
   474 header.
   475 
   476 * Simplification procedure "list_to_set_comprehension" rewrites list
   477 comprehensions applied to List.set to set comprehensions.  Occasional
   478 INCOMPATIBILITY, may be deactivated like this:
   479 
   480   declare [[simproc del: list_to_set_comprehension]]
   481 
   482 * Removed old version of primrec package.  INCOMPATIBILITY.
   483 
   484 * Removed simplifier congruence rule of "prod_case", as has for long
   485 been the case with "split".  INCOMPATIBILITY.
   486 
   487 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   488 
   489 * Removed [split_format ... and ... and ...] version of
   490 [split_format].  Potential INCOMPATIBILITY.
   491 
   492 * Predicate "sorted" now defined inductively, with nice induction
   493 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   494 
   495 * Constant "contents" renamed to "the_elem", to free the generic name
   496 contents for other uses.  INCOMPATIBILITY.
   497 
   498 * Renamed class eq and constant eq (for code generation) to class
   499 equal and constant equal, plus renaming of related facts and various
   500 tuning.  INCOMPATIBILITY.
   501 
   502 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   503 
   504 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   505 INCOMPATIBILITY.
   506 
   507 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   508 avoid confusion with finite sets.  INCOMPATIBILITY.
   509 
   510 * Abandoned locales equiv, congruent and congruent2 for equivalence
   511 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   512 for congruent(2)).
   513 
   514 * Some previously unqualified names have been qualified:
   515 
   516   types
   517     bool ~> HOL.bool
   518     nat ~> Nat.nat
   519 
   520   constants
   521     Trueprop ~> HOL.Trueprop
   522     True ~> HOL.True
   523     False ~> HOL.False
   524     op & ~> HOL.conj
   525     op | ~> HOL.disj
   526     op --> ~> HOL.implies
   527     op = ~> HOL.eq
   528     Not ~> HOL.Not
   529     The ~> HOL.The
   530     All ~> HOL.All
   531     Ex ~> HOL.Ex
   532     Ex1 ~> HOL.Ex1
   533     Let ~> HOL.Let
   534     If ~> HOL.If
   535     Ball ~> Set.Ball
   536     Bex ~> Set.Bex
   537     Suc ~> Nat.Suc
   538     Pair ~> Product_Type.Pair
   539     fst ~> Product_Type.fst
   540     snd ~> Product_Type.snd
   541     curry ~> Product_Type.curry
   542     op : ~> Set.member
   543     Collect ~> Set.Collect
   544 
   545 INCOMPATIBILITY.
   546 
   547 * More canonical naming convention for some fundamental definitions:
   548 
   549     bot_bool_eq ~> bot_bool_def
   550     top_bool_eq ~> top_bool_def
   551     inf_bool_eq ~> inf_bool_def
   552     sup_bool_eq ~> sup_bool_def
   553     bot_fun_eq  ~> bot_fun_def
   554     top_fun_eq  ~> top_fun_def
   555     inf_fun_eq  ~> inf_fun_def
   556     sup_fun_eq  ~> sup_fun_def
   557 
   558 INCOMPATIBILITY.
   559 
   560 * More stylized fact names:
   561 
   562   expand_fun_eq ~> fun_eq_iff
   563   expand_set_eq ~> set_eq_iff
   564   set_ext       ~> set_eqI
   565   nat_number    ~> eval_nat_numeral
   566 
   567 INCOMPATIBILITY.
   568 
   569 * Refactoring of code-generation specific operations in theory List:
   570 
   571   constants
   572     null ~> List.null
   573 
   574   facts
   575     mem_iff ~> member_def
   576     null_empty ~> null_def
   577 
   578 INCOMPATIBILITY.  Note that these were not supposed to be used
   579 regularly unless for striking reasons; their main purpose was code
   580 generation.
   581 
   582 Various operations from the Haskell prelude are used for generating
   583 Haskell code.
   584 
   585 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   586 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   587 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   588 
   589 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   590 "*" and "+" respectively.  INCOMPATIBILITY.
   591 
   592 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   593 "Sum_Type.Plus" instead.
   594 
   595 * Constant "split" has been merged with constant "prod_case"; names of
   596 ML functions, facts etc. involving split have been retained so far,
   597 though.  INCOMPATIBILITY.
   598 
   599 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   600 instead.  INCOMPATIBILITY.
   601 
   602 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   603 INCOMPATIBILITY.
   604 
   605 * Former theory Library/Enum is now part of the HOL-Main image.
   606 INCOMPATIBILITY: all constants of the Enum theory now have to be
   607 referred to by its qualified name.
   608 
   609   enum    ~>  Enum.enum
   610   nlists  ~>  Enum.nlists
   611   product ~>  Enum.product
   612 
   613 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   614 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   615 INCOMPATIBILITY.
   616 
   617 * Theory Library/SetsAndFunctions has been split into
   618 Library/Function_Algebras and Library/Set_Algebras; canonical names
   619 for instance definitions for functions; various improvements.
   620 INCOMPATIBILITY.
   621 
   622 * Theory Library/Multiset provides stable quicksort implementation of
   623 sort_key.
   624 
   625 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   626 INCOMPATIBILITY.
   627 
   628 * Session Multivariate_Analysis: introduced a type class for euclidean
   629 space.  Most theorems are now stated in terms of euclidean spaces
   630 instead of finite cartesian products.
   631 
   632   types
   633     real ^ 'n ~>  'a::real_vector
   634               ~>  'a::euclidean_space
   635               ~>  'a::ordered_euclidean_space
   636         (depends on your needs)
   637 
   638   constants
   639      _ $ _        ~> _ $$ _
   640      \<chi> x. _  ~> \<chi>\<chi> x. _
   641      CARD('n)     ~> DIM('a)
   642 
   643 Also note that the indices are now natural numbers and not from some
   644 finite type. Finite cartesian products of euclidean spaces, products
   645 of euclidean spaces the real and complex numbers are instantiated to
   646 be euclidean_spaces.  INCOMPATIBILITY.
   647 
   648 * Session Probability: introduced pextreal as positive extended real
   649 numbers.  Use pextreal as value for measures.  Introduce the
   650 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   651 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   652 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   653 
   654 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   655 INCOMPATIBILITY.
   656 
   657 * Session SPARK (with image HOL-SPARK) provides commands to load and
   658 prove verification conditions generated by the SPARK Ada program
   659 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   660 
   661 
   662 *** HOL-Algebra ***
   663 
   664 * Theorems for additive ring operations (locale abelian_monoid and
   665 descendants) are generated by interpretation from their multiplicative
   666 counterparts.  Names (in particular theorem names) have the mandatory
   667 qualifier 'add'.  Previous theorem names are redeclared for
   668 compatibility.
   669 
   670 * Structure "int_ring" is now an abbreviation (previously a
   671 definition).  This fits more natural with advanced interpretations.
   672 
   673 
   674 *** HOLCF ***
   675 
   676 * The domain package now runs in definitional mode by default: The
   677 former command 'new_domain' is now called 'domain'.  To use the domain
   678 package in its original axiomatic mode, use 'domain (unsafe)'.
   679 INCOMPATIBILITY.
   680 
   681 * The new class "domain" is now the default sort.  Class "predomain"
   682 is an unpointed version of "domain". Theories can be updated by
   683 replacing sort annotations as shown below.  INCOMPATIBILITY.
   684 
   685   'a::type ~> 'a::countable
   686   'a::cpo  ~> 'a::predomain
   687   'a::pcpo ~> 'a::domain
   688 
   689 * The old type class "rep" has been superseded by class "domain".
   690 Accordingly, users of the definitional package must remove any
   691 "default_sort rep" declarations.  INCOMPATIBILITY.
   692 
   693 * The domain package (definitional mode) now supports unpointed
   694 predomain argument types, as long as they are marked 'lazy'. (Strict
   695 arguments must be in class "domain".) For example, the following
   696 domain definition now works:
   697 
   698   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   699 
   700 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   701 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   702 'a option, and 'a list.  Additionally, it configures fixrec and the
   703 domain package to work with these types.  For example:
   704 
   705   fixrec isInl :: "('a + 'b) u -> tr"
   706     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   707 
   708   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   709 
   710 * The "(permissive)" option of fixrec has been replaced with a
   711 per-equation "(unchecked)" option. See
   712 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
   713 
   714 * The "bifinite" class no longer fixes a constant "approx"; the class
   715 now just asserts that such a function exists.  INCOMPATIBILITY.
   716 
   717 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
   718 defines an embedding of type 'a defl into udom by default; instances
   719 of "bifinite" and "domain" classes are available in
   720 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
   721 
   722 * The syntax "REP('a)" has been replaced with "DEFL('a)".
   723 
   724 * The predicate "directed" has been removed.  INCOMPATIBILITY.
   725 
   726 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
   727 
   728 * The function "cprod_map" has been renamed to "prod_map".
   729 INCOMPATIBILITY.
   730 
   731 * The monadic bind operator on each powerdomain has new binder syntax
   732 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
   733 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
   734 
   735 * The infix syntax for binary union on each powerdomain has changed
   736 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
   737 syntax.  INCOMPATIBILITY.
   738 
   739 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
   740 still supported as an input translation.
   741 
   742 * Renamed some theorems (the original names are also still available).
   743 
   744   expand_fun_below   ~> fun_below_iff
   745   below_fun_ext      ~> fun_belowI
   746   expand_cfun_eq     ~> cfun_eq_iff
   747   ext_cfun           ~> cfun_eqI
   748   expand_cfun_below  ~> cfun_below_iff
   749   below_cfun_ext     ~> cfun_belowI
   750   cont2cont_Rep_CFun ~> cont2cont_APP
   751 
   752 * The Abs and Rep functions for various types have changed names.
   753 Related theorem names have also changed to match. INCOMPATIBILITY.
   754 
   755   Rep_CFun  ~> Rep_cfun
   756   Abs_CFun  ~> Abs_cfun
   757   Rep_Sprod ~> Rep_sprod
   758   Abs_Sprod ~> Abs_sprod
   759   Rep_Ssum  ~> Rep_ssum
   760   Abs_Ssum  ~> Abs_ssum
   761 
   762 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   763 been renamed to *_bottom_iff.  INCOMPATIBILITY.
   764 
   765 * Various changes to bisimulation/coinduction with domain package:
   766 
   767   - Definitions of "bisim" constants no longer mention definedness.
   768   - With mutual recursion, "bisim" predicate is now curried.
   769   - With mutual recursion, each type gets a separate coind theorem.
   770   - Variable names in bisim_def and coinduct rules have changed.
   771 
   772 INCOMPATIBILITY.
   773 
   774 * Case combinators generated by the domain package for type "foo" are
   775 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
   776 
   777 * Several theorems have been renamed to more accurately reflect the
   778 names of constants and types involved.  INCOMPATIBILITY.
   779 
   780   thelub_const    ~> lub_const
   781   lub_const       ~> is_lub_const
   782   thelubI         ~> lub_eqI
   783   is_lub_lub      ~> is_lubD2
   784   lubI            ~> is_lub_lub
   785   unique_lub      ~> is_lub_unique
   786   is_ub_lub       ~> is_lub_rangeD1
   787   lub_bin_chain   ~> is_lub_bin_chain
   788   lub_fun         ~> is_lub_fun
   789   thelub_fun      ~> lub_fun
   790   thelub_cfun     ~> lub_cfun
   791   thelub_Pair     ~> lub_Pair
   792   lub_cprod       ~> is_lub_prod
   793   thelub_cprod    ~> lub_prod
   794   minimal_cprod   ~> minimal_prod
   795   inst_cprod_pcpo ~> inst_prod_pcpo
   796   UU_I            ~> bottomI
   797   compact_UU      ~> compact_bottom
   798   deflation_UU    ~> deflation_bottom
   799   finite_deflation_UU ~> finite_deflation_bottom
   800 
   801 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
   802 
   803   sq_ord_less_eq_trans ~> below_eq_trans
   804   sq_ord_eq_less_trans ~> eq_below_trans
   805   refl_less            ~> below_refl
   806   trans_less           ~> below_trans
   807   antisym_less         ~> below_antisym
   808   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
   809   box_less             ~> box_below
   810   rev_trans_less       ~> rev_below_trans
   811   not_less2not_eq      ~> not_below2not_eq
   812   less_UU_iff          ~> below_UU_iff
   813   flat_less_iff        ~> flat_below_iff
   814   adm_less             ~> adm_below
   815   adm_not_less         ~> adm_not_below
   816   adm_compact_not_less ~> adm_compact_not_below
   817   less_fun_def         ~> below_fun_def
   818   expand_fun_less      ~> fun_below_iff
   819   less_fun_ext         ~> fun_belowI
   820   less_discr_def       ~> below_discr_def
   821   discr_less_eq        ~> discr_below_eq
   822   less_unit_def        ~> below_unit_def
   823   less_cprod_def       ~> below_prod_def
   824   prod_lessI           ~> prod_belowI
   825   Pair_less_iff        ~> Pair_below_iff
   826   fst_less_iff         ~> fst_below_iff
   827   snd_less_iff         ~> snd_below_iff
   828   expand_cfun_less     ~> cfun_below_iff
   829   less_cfun_ext        ~> cfun_belowI
   830   injection_less       ~> injection_below
   831   less_up_def          ~> below_up_def
   832   not_Iup_less         ~> not_Iup_below
   833   Iup_less             ~> Iup_below
   834   up_less              ~> up_below
   835   Def_inject_less_eq   ~> Def_below_Def
   836   Def_less_is_eq       ~> Def_below_iff
   837   spair_less_iff       ~> spair_below_iff
   838   less_sprod           ~> below_sprod
   839   spair_less           ~> spair_below
   840   sfst_less_iff        ~> sfst_below_iff
   841   ssnd_less_iff        ~> ssnd_below_iff
   842   fix_least_less       ~> fix_least_below
   843   dist_less_one        ~> dist_below_one
   844   less_ONE             ~> below_ONE
   845   ONE_less_iff         ~> ONE_below_iff
   846   less_sinlD           ~> below_sinlD
   847   less_sinrD           ~> below_sinrD
   848 
   849 
   850 *** FOL and ZF ***
   851 
   852 * All constant names are now qualified internally and use proper
   853 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
   854 
   855 
   856 *** ML ***
   857 
   858 * Antiquotation @{assert} inlines a function bool -> unit that raises
   859 Fail if the argument is false.  Due to inlining the source position of
   860 failed assertions is included in the error output.
   861 
   862 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
   863 text is in practice always evaluated with a stable theory checkpoint.
   864 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
   865 
   866 * Antiquotation @{theory A} refers to theory A from the ancestry of
   867 the current context, not any accidental theory loader state as before.
   868 Potential INCOMPATIBILITY, subtle change in semantics.
   869 
   870 * Syntax.pretty_priority (default 0) configures the required priority
   871 of pretty-printed output and thus affects insertion of parentheses.
   872 
   873 * Syntax.default_root (default "any") configures the inner syntax
   874 category (nonterminal symbol) for parsing of terms.
   875 
   876 * Former exception Library.UnequalLengths now coincides with
   877 ListPair.UnequalLengths.
   878 
   879 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
   880 main functionality is provided by structure Simplifier.
   881 
   882 * Renamed raw "explode" function to "raw_explode" to emphasize its
   883 meaning.  Note that internally to Isabelle, Symbol.explode is used in
   884 almost all situations.
   885 
   886 * Discontinued obsolete function sys_error and exception SYS_ERROR.
   887 See implementation manual for further details on exceptions in
   888 Isabelle/ML.
   889 
   890 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   891 meaning.
   892 
   893 * Renamed structure PureThy to Pure_Thy and moved most of its
   894 operations to structure Global_Theory, to emphasize that this is
   895 rarely-used global-only stuff.
   896 
   897 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
   898 instead (or tracing for high-volume output).
   899 
   900 * Configuration option show_question_marks only affects regular pretty
   901 printing of types and terms, not raw Term.string_of_vname.
   902 
   903 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
   904 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
   905 @{thms} for most purposes.
   906 
   907 * ML structure Unsynchronized is never opened, not even in Isar
   908 interaction mode as before.  Old Unsynchronized.set etc. have been
   909 discontinued -- use plain := instead.  This should be *rare* anyway,
   910 since modern tools always work via official context data, notably
   911 configuration options.
   912 
   913 * Parallel and asynchronous execution requires special care concerning
   914 interrupts.  Structure Exn provides some convenience functions that
   915 avoid working directly with raw Interrupt.  User code must not absorb
   916 interrupts -- intermediate handling (for cleanup etc.) needs to be
   917 followed by re-raising of the original exception.  Another common
   918 source of mistakes are "handle _" patterns, which make the meaning of
   919 the program subject to physical effects of the environment.
   920 
   921 
   922 
   923 New in Isabelle2009-2 (June 2010)
   924 ---------------------------------
   925 
   926 *** General ***
   927 
   928 * Authentic syntax for *all* logical entities (type classes, type
   929 constructors, term constants): provides simple and robust
   930 correspondence between formal entities and concrete syntax.  Within
   931 the parse tree / AST representations, "constants" are decorated by
   932 their category (class, type, const) and spelled out explicitly with
   933 their full internal name.
   934 
   935 Substantial INCOMPATIBILITY concerning low-level syntax declarations
   936 and translations (translation rules and translation functions in ML).
   937 Some hints on upgrading:
   938 
   939   - Many existing uses of 'syntax' and 'translations' can be replaced
   940     by more modern 'type_notation', 'notation' and 'abbreviation',
   941     which are independent of this issue.
   942 
   943   - 'translations' require markup within the AST; the term syntax
   944     provides the following special forms:
   945 
   946       CONST c   -- produces syntax version of constant c from context
   947       XCONST c  -- literally c, checked as constant from context
   948       c         -- literally c, if declared by 'syntax'
   949 
   950     Plain identifiers are treated as AST variables -- occasionally the
   951     system indicates accidental variables via the error "rhs contains
   952     extra variables".
   953 
   954     Type classes and type constructors are marked according to their
   955     concrete syntax.  Some old translations rules need to be written
   956     for the "type" category, using type constructor application
   957     instead of pseudo-term application of the default category
   958     "logic".
   959 
   960   - 'parse_translation' etc. in ML may use the following
   961     antiquotations:
   962 
   963       @{class_syntax c}   -- type class c within parse tree / AST
   964       @{term_syntax c}    -- type constructor c within parse tree / AST
   965       @{const_syntax c}   -- ML version of "CONST c" above
   966       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
   967 
   968   - Literal types within 'typed_print_translations', i.e. those *not*
   969     represented as pseudo-terms are represented verbatim.  Use @{class
   970     c} or @{type_name c} here instead of the above syntax
   971     antiquotations.
   972 
   973 Note that old non-authentic syntax was based on unqualified base
   974 names, so all of the above "constant" names would coincide.  Recall
   975 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
   976 diagnose syntax problems.
   977 
   978 * Type constructors admit general mixfix syntax, not just infix.
   979 
   980 * Concrete syntax may be attached to local entities without a proof
   981 body, too.  This works via regular mixfix annotations for 'fix',
   982 'def', 'obtain' etc. or via the explicit 'write' command, which is
   983 similar to the 'notation' command in theory specifications.
   984 
   985 * Discontinued unnamed infix syntax (legacy feature for many years) --
   986 need to specify constant name and syntax separately.  Internal ML
   987 datatype constructors have been renamed from InfixName to Infix etc.
   988 Minor INCOMPATIBILITY.
   989 
   990 * Schematic theorem statements need to be explicitly markup as such,
   991 via commands 'schematic_lemma', 'schematic_theorem',
   992 'schematic_corollary'.  Thus the relevance of the proof is made
   993 syntactically clear, which impacts performance in a parallel or
   994 asynchronous interactive environment.  Minor INCOMPATIBILITY.
   995 
   996 * Use of cumulative prems via "!" in some proof methods has been
   997 discontinued (old legacy feature).
   998 
   999 * References 'trace_simp' and 'debug_simp' have been replaced by
  1000 configuration options stored in the context. Enabling tracing (the
  1001 case of debugging is similar) in proofs works via
  1002 
  1003   using [[trace_simp = true]]
  1004 
  1005 Tracing is then active for all invocations of the simplifier in
  1006 subsequent goal refinement steps. Tracing may also still be enabled or
  1007 disabled via the ProofGeneral settings menu.
  1008 
  1009 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  1010 'hide_fact' replace the former 'hide' KIND command.  Minor
  1011 INCOMPATIBILITY.
  1012 
  1013 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  1014 more efficient than combinations with -q1 or -q2.
  1015 
  1016 
  1017 *** Pure ***
  1018 
  1019 * Proofterms record type-class reasoning explicitly, using the
  1020 "unconstrain" operation internally.  This eliminates all sort
  1021 constraints from a theorem and proof, introducing explicit
  1022 OFCLASS-premises.  On the proof term level, this operation is
  1023 automatically applied at theorem boundaries, such that closed proofs
  1024 are always free of sort constraints.  INCOMPATIBILITY for tools that
  1025 inspect proof terms.
  1026 
  1027 * Local theory specifications may depend on extra type variables that
  1028 are not present in the result type -- arguments TYPE('a) :: 'a itself
  1029 are added internally.  For example:
  1030 
  1031   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  1032 
  1033 * Predicates of locales introduced by classes carry a mandatory
  1034 "class" prefix.  INCOMPATIBILITY.
  1035 
  1036 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  1037 
  1038 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  1039 'class' instead.
  1040 
  1041 * Command 'code_reflect' allows to incorporate generated ML code into
  1042 runtime environment; replaces immature code_datatype antiquotation.
  1043 INCOMPATIBILITY.
  1044 
  1045 * Code generator: simple concept for abstract datatypes obeying
  1046 invariants.
  1047 
  1048 * Code generator: details of internal data cache have no impact on the
  1049 user space functionality any longer.
  1050 
  1051 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1052 subgoals.  This is more appropriate for interpretations with 'where'.
  1053 INCOMPATIBILITY.
  1054 
  1055 * Command 'example_proof' opens an empty proof body.  This allows to
  1056 experiment with Isar, without producing any persistent result.
  1057 
  1058 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1059 within a local theory context, with explicit checking of the
  1060 constructors involved (in contrast to the raw 'syntax' versions).
  1061 
  1062 * Commands 'types' and 'typedecl' now work within a local theory
  1063 context -- without introducing dependencies on parameters or
  1064 assumptions, which is not possible in Isabelle/Pure.
  1065 
  1066 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1067 within a local theory context.  Minor INCOMPATIBILITY.
  1068 
  1069 
  1070 *** HOL ***
  1071 
  1072 * Command 'typedef' now works within a local theory context -- without
  1073 introducing dependencies on parameters or assumptions, which is not
  1074 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1075 contain multiple interpretations of local typedefs (with different
  1076 non-emptiness proofs), even in a global theory context.
  1077 
  1078 * New package for quotient types.  Commands 'quotient_type' and
  1079 'quotient_definition' may be used for defining types and constants by
  1080 quotient constructions.  An example is the type of integers created by
  1081 quotienting pairs of natural numbers:
  1082 
  1083   fun
  1084     intrel :: "(nat * nat) => (nat * nat) => bool"
  1085   where
  1086     "intrel (x, y) (u, v) = (x + v = u + y)"
  1087 
  1088   quotient_type int = "nat * nat" / intrel
  1089     by (auto simp add: equivp_def expand_fun_eq)
  1090 
  1091   quotient_definition
  1092     "0::int" is "(0::nat, 0::nat)"
  1093 
  1094 The method "lifting" can be used to lift of theorems from the
  1095 underlying "raw" type to the quotient type.  The example
  1096 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1097 construction and provides a reasoning infrastructure for finite sets.
  1098 
  1099 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1100 clash with new theory Quotient in Main HOL.
  1101 
  1102 * Moved the SMT binding into the main HOL session, eliminating
  1103 separate HOL-SMT session.
  1104 
  1105 * List membership infix mem operation is only an input abbreviation.
  1106 INCOMPATIBILITY.
  1107 
  1108 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1109 for future developements; former Library/Word.thy is still present in
  1110 the AFP entry RSAPPS.
  1111 
  1112 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1113 longer shadowed.  INCOMPATIBILITY.
  1114 
  1115 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1116 INCOMPATIBILITY.
  1117 
  1118 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1119 INCOMPATIBILITY.
  1120 
  1121 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1122 instead.  INCOMPATIBILITY.
  1123 
  1124 * Dropped several real-specific versions of lemmas about floor and
  1125 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1126 instead.  INCOMPATIBILITY.
  1127 
  1128   floor_number_of_eq         ~> floor_number_of
  1129   le_floor_eq_number_of      ~> number_of_le_floor
  1130   le_floor_eq_zero           ~> zero_le_floor
  1131   le_floor_eq_one            ~> one_le_floor
  1132   floor_less_eq_number_of    ~> floor_less_number_of
  1133   floor_less_eq_zero         ~> floor_less_zero
  1134   floor_less_eq_one          ~> floor_less_one
  1135   less_floor_eq_number_of    ~> number_of_less_floor
  1136   less_floor_eq_zero         ~> zero_less_floor
  1137   less_floor_eq_one          ~> one_less_floor
  1138   floor_le_eq_number_of      ~> floor_le_number_of
  1139   floor_le_eq_zero           ~> floor_le_zero
  1140   floor_le_eq_one            ~> floor_le_one
  1141   floor_subtract_number_of   ~> floor_diff_number_of
  1142   floor_subtract_one         ~> floor_diff_one
  1143   ceiling_number_of_eq       ~> ceiling_number_of
  1144   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1145   ceiling_le_zero_eq         ~> ceiling_le_zero
  1146   ceiling_le_eq_one          ~> ceiling_le_one
  1147   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1148   less_ceiling_eq_zero       ~> zero_less_ceiling
  1149   less_ceiling_eq_one        ~> one_less_ceiling
  1150   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1151   ceiling_less_eq_zero       ~> ceiling_less_zero
  1152   ceiling_less_eq_one        ~> ceiling_less_one
  1153   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1154   le_ceiling_eq_zero         ~> zero_le_ceiling
  1155   le_ceiling_eq_one          ~> one_le_ceiling
  1156   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1157   ceiling_subtract_one       ~> ceiling_diff_one
  1158 
  1159 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1160 application of the various fold combinators on finite sets.
  1161 
  1162 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1163 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1164 implementation.  INCOMPATIBILTY.
  1165 
  1166 * Theory Library/Coinductive_List has been removed -- superseded by
  1167 AFP/thys/Coinductive.
  1168 
  1169 * Theory PReal, including the type "preal" and related operations, has
  1170 been removed.  INCOMPATIBILITY.
  1171 
  1172 * Real: new development using Cauchy Sequences.
  1173 
  1174 * Split off theory "Big_Operators" containing setsum, setprod,
  1175 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1176 
  1177 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1178 "Int" etc.  INCOMPATIBILITY.
  1179 
  1180 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1181 
  1182 * New set of rules "ac_simps" provides combined assoc / commute
  1183 rewrites for all interpretations of the appropriate generic locales.
  1184 
  1185 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1186 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1187 appropriate and more consistent names suitable for name prefixes
  1188 within the HOL theories.  INCOMPATIBILITY.
  1189 
  1190 * Some generic constants have been put to appropriate theories:
  1191   - less_eq, less: Orderings
  1192   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1193   - inverse, divide: Rings
  1194 INCOMPATIBILITY.
  1195 
  1196 * More consistent naming of type classes involving orderings (and
  1197 lattices):
  1198 
  1199     lower_semilattice                   ~> semilattice_inf
  1200     upper_semilattice                   ~> semilattice_sup
  1201 
  1202     dense_linear_order                  ~> dense_linorder
  1203 
  1204     pordered_ab_group_add               ~> ordered_ab_group_add
  1205     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1206     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1207     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1208     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1209     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1210     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1211     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1212     pordered_comm_ring                  ~> ordered_comm_ring
  1213     pordered_comm_semiring              ~> ordered_comm_semiring
  1214     pordered_ring                       ~> ordered_ring
  1215     pordered_ring_abs                   ~> ordered_ring_abs
  1216     pordered_semiring                   ~> ordered_semiring
  1217 
  1218     ordered_ab_group_add                ~> linordered_ab_group_add
  1219     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1220     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1221     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1222     ordered_field                       ~> linordered_field
  1223     ordered_field_no_lb                 ~> linordered_field_no_lb
  1224     ordered_field_no_ub                 ~> linordered_field_no_ub
  1225     ordered_field_dense_linear_order    ~> dense_linordered_field
  1226     ordered_idom                        ~> linordered_idom
  1227     ordered_ring                        ~> linordered_ring
  1228     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1229     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1230     ordered_ring_strict                 ~> linordered_ring_strict
  1231     ordered_semidom                     ~> linordered_semidom
  1232     ordered_semiring                    ~> linordered_semiring
  1233     ordered_semiring_1                  ~> linordered_semiring_1
  1234     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1235     ordered_semiring_strict             ~> linordered_semiring_strict
  1236 
  1237   The following slightly odd type classes have been moved to a
  1238   separate theory Library/Lattice_Algebras:
  1239 
  1240     lordered_ab_group_add               ~> lattice_ab_group_add
  1241     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1242     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1243     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1244     lordered_ring                       ~> lattice_ring
  1245 
  1246 INCOMPATIBILITY.
  1247 
  1248 * Refined field classes:
  1249   - classes division_ring_inverse_zero, field_inverse_zero,
  1250     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1251     subsumes former division_by_zero class;
  1252   - numerous lemmas have been ported from field to division_ring.
  1253 INCOMPATIBILITY.
  1254 
  1255 * Refined algebra theorem collections:
  1256   - dropped theorem group group_simps, use algebra_simps instead;
  1257   - dropped theorem group ring_simps, use field_simps instead;
  1258   - proper theorem collection field_simps subsumes former theorem
  1259     groups field_eq_simps and field_simps;
  1260   - dropped lemma eq_minus_self_iff which is a duplicate for
  1261     equal_neg_zero.
  1262 INCOMPATIBILITY.
  1263 
  1264 * Theory Finite_Set and List: some lemmas have been generalized from
  1265 sets to lattices:
  1266 
  1267   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1268   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1269   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1270   union_Union_fold_union        ~> sup_Sup_fold_sup
  1271   Inter_fold_inter              ~> Inf_fold_inf
  1272   Union_fold_union              ~> Sup_fold_sup
  1273   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1274   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1275   INTER_fold_inter              ~> INFI_fold_inf
  1276   UNION_fold_union              ~> SUPR_fold_sup
  1277 
  1278 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1279 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1280 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1281 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1282 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1283 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1284 
  1285 * Reorganized theory Multiset: swapped notation of pointwise and
  1286 multiset order:
  1287 
  1288   - pointwise ordering is instance of class order with standard syntax
  1289     <= and <;
  1290   - multiset ordering has syntax <=# and <#; partial order properties
  1291     are provided by means of interpretation with prefix
  1292     multiset_order;
  1293   - less duplication, less historical organization of sections,
  1294     conversion from associations lists to multisets, rudimentary code
  1295     generation;
  1296   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1297     if needed.
  1298 
  1299 Renamed:
  1300 
  1301   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1302   multi_count_ext  ~>  multiset_ext
  1303   diff_union_inverse2  ~>  diff_union_cancelR
  1304 
  1305 INCOMPATIBILITY.
  1306 
  1307 * Theory Permutation: replaced local "remove" by List.remove1.
  1308 
  1309 * Code generation: ML and OCaml code is decorated with signatures.
  1310 
  1311 * Theory List: added transpose.
  1312 
  1313 * Library/Nat_Bijection.thy is a collection of bijective functions
  1314 between nat and other types, which supersedes the older libraries
  1315 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1316 
  1317   Constants:
  1318   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1319   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1320   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1321   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1322   Countable.pair_encode           ~> prod_encode
  1323   NatIso.prod2nat                 ~> prod_encode
  1324   NatIso.nat2prod                 ~> prod_decode
  1325   NatIso.sum2nat                  ~> sum_encode
  1326   NatIso.nat2sum                  ~> sum_decode
  1327   NatIso.list2nat                 ~> list_encode
  1328   NatIso.nat2list                 ~> list_decode
  1329   NatIso.set2nat                  ~> set_encode
  1330   NatIso.nat2set                  ~> set_decode
  1331 
  1332   Lemmas:
  1333   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1334   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1335   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1336   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1337   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1338   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1339   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1340   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1341   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1342   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1343   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1344   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1345   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1346 
  1347 * Sledgehammer:
  1348   - Renamed ATP commands:
  1349     atp_info     ~> sledgehammer running_atps
  1350     atp_kill     ~> sledgehammer kill_atps
  1351     atp_messages ~> sledgehammer messages
  1352     atp_minimize ~> sledgehammer minimize
  1353     print_atps   ~> sledgehammer available_atps
  1354     INCOMPATIBILITY.
  1355   - Added user's manual ("isabelle doc sledgehammer").
  1356   - Added option syntax and "sledgehammer_params" to customize
  1357     Sledgehammer's behavior.  See the manual for details.
  1358   - Modified the Isar proof reconstruction code so that it produces
  1359     direct proofs rather than proofs by contradiction.  (This feature
  1360     is still experimental.)
  1361   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1362     full-typed mode.
  1363   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1364 
  1365 * Nitpick:
  1366   - Added and implemented "binary_ints" and "bits" options.
  1367   - Added "std" option and implemented support for nonstandard models.
  1368   - Added and implemented "finitize" option to improve the precision
  1369     of infinite datatypes based on a monotonicity analysis.
  1370   - Added support for quotient types.
  1371   - Added support for "specification" and "ax_specification"
  1372     constructs.
  1373   - Added support for local definitions (for "function" and
  1374     "termination" proofs).
  1375   - Added support for term postprocessors.
  1376   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1377   - Improved efficiency of "destroy_constrs" optimization.
  1378   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1379     record getters.
  1380   - Fixed soundness bug related to higher-order constructors.
  1381   - Fixed soundness bug when "full_descrs" is enabled.
  1382   - Improved precision of set constructs.
  1383   - Added "atoms" option.
  1384   - Added cache to speed up repeated Kodkod invocations on the same
  1385     problems.
  1386   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1387     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1388     "SAT4J_Light".  INCOMPATIBILITY.
  1389   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1390     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1391   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1392 
  1393 * Method "induct" now takes instantiations of the form t, where t is not
  1394   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1395   If this is not intended, t has to be enclosed in parentheses.
  1396   By default, the equalities generated by definitional instantiations
  1397   are pre-simplified, which may cause parameters of inductive cases
  1398   to disappear, or may even delete some of the inductive cases.
  1399   Use "induct (no_simp)" instead of "induct" to restore the old
  1400   behaviour. The (no_simp) option is also understood by the "cases"
  1401   and "nominal_induct" methods, which now perform pre-simplification, too.
  1402   INCOMPATIBILITY.
  1403 
  1404 
  1405 *** HOLCF ***
  1406 
  1407 * Variable names in lemmas generated by the domain package have
  1408 changed; the naming scheme is now consistent with the HOL datatype
  1409 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1410 
  1411 * The domain package no longer defines the function "foo_copy" for
  1412 recursive domain "foo".  The reach lemma is now stated directly in
  1413 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1414 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1415 
  1416 * Most definedness lemmas generated by the domain package (previously
  1417 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1418 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1419 Proofs that used definedness lemmas as intro rules may break,
  1420 potential INCOMPATIBILITY.
  1421 
  1422 * Induction and casedist rules generated by the domain package now
  1423 declare proper case_names (one called "bottom", and one named for each
  1424 constructor).  INCOMPATIBILITY.
  1425 
  1426 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1427 rules are generated for each domain, INCOMPATIBILITY.
  1428 
  1429   foo_bar.reach       ~> foo.reach  bar.reach
  1430   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1431 
  1432 * Some lemmas generated by the domain package have been renamed for
  1433 consistency with the datatype package, INCOMPATIBILITY.
  1434 
  1435   foo.ind        ~> foo.induct
  1436   foo.finite_ind ~> foo.finite_induct
  1437   foo.coind      ~> foo.coinduct
  1438   foo.casedist   ~> foo.exhaust
  1439   foo.exhaust    ~> foo.nchotomy
  1440 
  1441 * For consistency with other definition packages, the fixrec package
  1442 now generates qualified theorem names, INCOMPATIBILITY.
  1443 
  1444   foo_simps  ~> foo.simps
  1445   foo_unfold ~> foo.unfold
  1446   foo_induct ~> foo.induct
  1447 
  1448 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1449 method and internal fixrec proofs now use the default simpset instead.
  1450 INCOMPATIBILITY.
  1451 
  1452 * The "contlub" predicate has been removed.  Proof scripts should use
  1453 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1454 
  1455 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1456 
  1457 * The constants cpair, cfst, and csnd have been removed in favor of
  1458 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1459 
  1460 
  1461 *** ML ***
  1462 
  1463 * Antiquotations for basic formal entities:
  1464 
  1465     @{class NAME}         -- type class
  1466     @{class_syntax NAME}  -- syntax representation of the above
  1467 
  1468     @{type_name NAME}     -- logical type
  1469     @{type_abbrev NAME}   -- type abbreviation
  1470     @{nonterminal NAME}   -- type of concrete syntactic category
  1471     @{type_syntax NAME}   -- syntax representation of any of the above
  1472 
  1473     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1474     @{const_abbrev NAME}  -- abbreviated constant
  1475     @{const_syntax NAME}  -- syntax representation of any of the above
  1476 
  1477 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1478 syntax constant (cf. 'syntax' command).
  1479 
  1480 * Antiquotation @{make_string} inlines a function to print arbitrary
  1481 values similar to the ML toplevel.  The result is compiler dependent
  1482 and may fall back on "?" in certain situations.
  1483 
  1484 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1485 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1486 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1487 not work with the asynchronous Isar document model.
  1488 
  1489 * Configuration options now admit dynamic default values, depending on
  1490 the context or even global references.
  1491 
  1492 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1493 uses an efficient external library if available (for Poly/ML).
  1494 
  1495 * Renamed some important ML structures, while keeping the old names
  1496 for some time as aliases within the structure Legacy:
  1497 
  1498   OuterKeyword  ~>  Keyword
  1499   OuterLex      ~>  Token
  1500   OuterParse    ~>  Parse
  1501   OuterSyntax   ~>  Outer_Syntax
  1502   PrintMode     ~>  Print_Mode
  1503   SpecParse     ~>  Parse_Spec
  1504   ThyInfo       ~>  Thy_Info
  1505   ThyLoad       ~>  Thy_Load
  1506   ThyOutput     ~>  Thy_Output
  1507   TypeInfer     ~>  Type_Infer
  1508 
  1509 Note that "open Legacy" simplifies porting of sources, but forgetting
  1510 to remove it again will complicate porting again in the future.
  1511 
  1512 * Most operations that refer to a global context are named
  1513 accordingly, e.g. Simplifier.global_context or
  1514 ProofContext.init_global.  There are some situations where a global
  1515 context actually works, but under normal circumstances one needs to
  1516 pass the proper local context through the code!
  1517 
  1518 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1519 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1520 Pretty.pp argument to merge, which is absent in the standard
  1521 Theory_Data version.
  1522 
  1523 * Sorts.certify_sort and derived "cert" operations for types and terms
  1524 no longer minimize sorts.  Thus certification at the boundary of the
  1525 inference kernel becomes invariant under addition of class relations,
  1526 which is an important monotonicity principle.  Sorts are now minimized
  1527 in the syntax layer only, at the boundary between the end-user and the
  1528 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1529 explicitly in rare situations.
  1530 
  1531 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1532 emphasize that this is in no way a standard operation.
  1533 INCOMPATIBILITY.
  1534 
  1535 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1536 usual for resolution.  Rare INCOMPATIBILITY.
  1537 
  1538 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1539 to emphasize that these only work in a global situation (which is
  1540 quite rare).
  1541 
  1542 * Curried take and drop in library.ML; negative length is interpreted
  1543 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1544 
  1545 * Proof terms: type substitutions on proof constants now use canonical
  1546 order of type variables.  INCOMPATIBILITY for tools working with proof
  1547 terms.
  1548 
  1549 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1550 may no longer carry premises.  User-level specifications are
  1551 transformed accordingly by Thm.add_axiom/add_def.
  1552 
  1553 
  1554 *** System ***
  1555 
  1556 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1557 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1558 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1559 
  1560 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1561 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1562 respectively.
  1563 
  1564 * Old lib/scripts/polyml-platform is superseded by the
  1565 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1566 variant, even on a 64 bit machine.  The following example setting
  1567 prefers 64 bit if available:
  1568 
  1569   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1570 
  1571 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1572 Isabelle/Scala layer for advanced prover interaction and integration.
  1573 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1574 component.
  1575 
  1576 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1577 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1578 similar to the default assignment of the document preparation system
  1579 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1580 provides some operations for direct access to the font without asking
  1581 the user for manual installation.
  1582 
  1583 
  1584 
  1585 New in Isabelle2009-1 (December 2009)
  1586 -------------------------------------
  1587 
  1588 *** General ***
  1589 
  1590 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1591 one backslash should be used, even in ML sources.
  1592 
  1593 
  1594 *** Pure ***
  1595 
  1596 * Locale interpretation propagates mixins along the locale hierarchy.
  1597 The currently only available mixins are the equations used to map
  1598 local definitions to terms of the target domain of an interpretation.
  1599 
  1600 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1601 loc" to print all interpretations of locale "loc" in the theory.
  1602 Interpretations in proofs are not shown.
  1603 
  1604 * Thoroughly revised locales tutorial.  New section on conditional
  1605 interpretation.
  1606 
  1607 * On instantiation of classes, remaining undefined class parameters
  1608 are formally declared.  INCOMPATIBILITY.
  1609 
  1610 
  1611 *** Document preparation ***
  1612 
  1613 * New generalized style concept for printing terms: @{foo (style) ...}
  1614 instead of @{foo_style style ...}  (old form is still retained for
  1615 backward compatibility).  Styles can be also applied for
  1616 antiquotations prop, term_type and typeof.
  1617 
  1618 
  1619 *** HOL ***
  1620 
  1621 * New proof method "smt" for a combination of first-order logic with
  1622 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1623 fixed-size bitvectors; there is also basic support for higher-order
  1624 features (esp. lambda abstractions).  It is an incomplete decision
  1625 procedure based on external SMT solvers using the oracle mechanism;
  1626 for the SMT solver Z3, this method is proof-producing.  Certificates
  1627 are provided to avoid calling the external solvers solely for
  1628 re-checking proofs.  Due to a remote SMT service there is no need for
  1629 installing SMT solvers locally.  See src/HOL/SMT.
  1630 
  1631 * New commands to load and prove verification conditions generated by
  1632 the Boogie program verifier or derived systems (e.g. the Verifying C
  1633 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1634 
  1635 * New counterexample generator tool 'nitpick' based on the Kodkod
  1636 relational model finder.  See src/HOL/Tools/Nitpick and
  1637 src/HOL/Nitpick_Examples.
  1638 
  1639 * New commands 'code_pred' and 'values' to invoke the predicate
  1640 compiler and to enumerate values of inductive predicates.
  1641 
  1642 * A tabled implementation of the reflexive transitive closure.
  1643 
  1644 * New implementation of quickcheck uses generic code generator;
  1645 default generators are provided for all suitable HOL types, records
  1646 and datatypes.  Old quickcheck can be re-activated importing theory
  1647 Library/SML_Quickcheck.
  1648 
  1649 * New testing tool Mirabelle for automated proof tools.  Applies
  1650 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1651 every proof step in a theory.  To be used in batch mode via the
  1652 "mirabelle" utility.
  1653 
  1654 * New proof method "sos" (sum of squares) for nonlinear real
  1655 arithmetic (originally due to John Harison). It requires theory
  1656 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1657 works well in practice on quantifier-free real arithmetic with +, -,
  1658 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1659 inequalities between polynomials.  It makes use of external
  1660 semidefinite programming solvers.  Method "sos" generates a
  1661 certificate that can be pasted into the proof thus avoiding the need
  1662 to call an external tool every time the proof is checked.  See
  1663 src/HOL/Library/Sum_Of_Squares.
  1664 
  1665 * New method "linarith" invokes existing linear arithmetic decision
  1666 procedure only.
  1667 
  1668 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1669 
  1670 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1671 Causes full type information to be output to the ATPs.  This slows
  1672 ATPs down considerably but eliminates a source of unsound "proofs"
  1673 that fail later.
  1674 
  1675 * New method "metisFT": A version of metis that uses full type
  1676 information in order to avoid failures of proof reconstruction.
  1677 
  1678 * New evaluator "approximate" approximates an real valued term using
  1679 the same method as the approximation method.
  1680 
  1681 * Method "approximate" now supports arithmetic expressions as
  1682 boundaries of intervals and implements interval splitting and Taylor
  1683 series expansion.
  1684 
  1685 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1686 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1687 
  1688 * New theory SupInf of the supremum and infimum operators for sets of
  1689 reals.
  1690 
  1691 * New theory Probability, which contains a development of measure
  1692 theory, eventually leading to Lebesgue integration and probability.
  1693 
  1694 * Extended Multivariate Analysis to include derivation and Brouwer's
  1695 fixpoint theorem.
  1696 
  1697 * Reorganization of number theory, INCOMPATIBILITY:
  1698   - new number theory development for nat and int, in theories Divides
  1699     and GCD as well as in new session Number_Theory
  1700   - some constants and facts now suffixed with _nat and _int
  1701     accordingly
  1702   - former session NumberTheory now named Old_Number_Theory, including
  1703     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1704   - moved theory Pocklington from src/HOL/Library to
  1705     src/HOL/Old_Number_Theory
  1706 
  1707 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1708 lcm of finite and infinite sets. It is shown that they form a complete
  1709 lattice.
  1710 
  1711 * Class semiring_div requires superclass no_zero_divisors and proof of
  1712 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1713 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1714 generalized to class semiring_div, subsuming former theorems
  1715 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1716 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1717 INCOMPATIBILITY.
  1718 
  1719 * Refinements to lattice classes and sets:
  1720   - less default intro/elim rules in locale variant, more default
  1721     intro/elim rules in class variant: more uniformity
  1722   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1723     le_inf_iff
  1724   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1725     sup_aci)
  1726   - renamed ACI to inf_sup_aci
  1727   - new class "boolean_algebra"
  1728   - class "complete_lattice" moved to separate theory
  1729     "Complete_Lattice"; corresponding constants (and abbreviations)
  1730     renamed and with authentic syntax:
  1731     Set.Inf ~>    Complete_Lattice.Inf
  1732     Set.Sup ~>    Complete_Lattice.Sup
  1733     Set.INFI ~>   Complete_Lattice.INFI
  1734     Set.SUPR ~>   Complete_Lattice.SUPR
  1735     Set.Inter ~>  Complete_Lattice.Inter
  1736     Set.Union ~>  Complete_Lattice.Union
  1737     Set.INTER ~>  Complete_Lattice.INTER
  1738     Set.UNION ~>  Complete_Lattice.UNION
  1739   - authentic syntax for
  1740     Set.Pow
  1741     Set.image
  1742   - mere abbreviations:
  1743     Set.empty               (for bot)
  1744     Set.UNIV                (for top)
  1745     Set.inter               (for inf, formerly Set.Int)
  1746     Set.union               (for sup, formerly Set.Un)
  1747     Complete_Lattice.Inter  (for Inf)
  1748     Complete_Lattice.Union  (for Sup)
  1749     Complete_Lattice.INTER  (for INFI)
  1750     Complete_Lattice.UNION  (for SUPR)
  1751   - object-logic definitions as far as appropriate
  1752 
  1753 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1754 Un_subset_iff are explicitly deleted as default simp rules; then also
  1755 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1756 deleted to achieve the desired effect.
  1757 
  1758 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1759 rules by default any longer; the same applies to min_max.inf_absorb1
  1760 etc.  INCOMPATIBILITY.
  1761 
  1762 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1763 pred_set_conv by default.  INCOMPATIBILITY.
  1764 
  1765 * Power operations on relations and functions are now one dedicated
  1766 constant "compow" with infix syntax "^^".  Power operation on
  1767 multiplicative monoids retains syntax "^" and is now defined generic
  1768 in class power.  INCOMPATIBILITY.
  1769 
  1770 * Relation composition "R O S" now has a more standard argument order:
  1771 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1772 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1773 break, since the O_assoc rule was not rewritten like this.  Fix using
  1774 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1775 
  1776 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1777 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1778 INCOMPATIBILITY.
  1779 
  1780 * Most rules produced by inductive and datatype package have mandatory
  1781 prefixes.  INCOMPATIBILITY.
  1782 
  1783 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1784 the attribute of the same name.  Each of the theorems in the list
  1785 DERIV_intros assumes composition with an additional function and
  1786 matches a variable to the derivative, which has to be solved by the
  1787 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1788 of most elementary terms.  Former Maclauren.DERIV_tac and
  1789 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1790 INCOMPATIBILITY.
  1791 
  1792 * Code generator attributes follow the usual underscore convention:
  1793     code_unfold     replaces    code unfold
  1794     code_post       replaces    code post
  1795     etc.
  1796   INCOMPATIBILITY.
  1797 
  1798 * Renamed methods:
  1799     sizechange -> size_change
  1800     induct_scheme -> induction_schema
  1801   INCOMPATIBILITY.
  1802 
  1803 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1804 INCOMPATIBILITY, use "undefined" directly.
  1805 
  1806 * Renamed theorems:
  1807     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1808     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1809     Suc_plus1 -> Suc_eq_plus1
  1810     *anti_sym -> *antisym*
  1811     vector_less_eq_def -> vector_le_def
  1812   INCOMPATIBILITY.
  1813 
  1814 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1815 INCOMPATIBILITY.
  1816 
  1817 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1818 INCOMPATIBILITY.
  1819 
  1820 
  1821 *** HOLCF ***
  1822 
  1823 * Theory Representable defines a class "rep" of domains that are
  1824 representable (via an ep-pair) in the universal domain type "udom".
  1825 Instances are provided for all type constructors defined in HOLCF.
  1826 
  1827 * The 'new_domain' command is a purely definitional version of the
  1828 domain package, for representable domains.  Syntax is identical to the
  1829 old domain package.  The 'new_domain' package also supports indirect
  1830 recursion using previously-defined type constructors.  See
  1831 src/HOLCF/ex/New_Domain.thy for examples.
  1832 
  1833 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1834 on the left-hand side of an equation, and then performs
  1835 simplification.  Rewriting is done using rules declared with the
  1836 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1837 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1838 
  1839 * The pattern-match compiler in 'fixrec' can now handle constructors
  1840 with HOL function types.  Pattern-match combinators for the Pair
  1841 constructor are pre-configured.
  1842 
  1843 * The 'fixrec' package now produces better fixed-point induction rules
  1844 for mutually-recursive definitions:  Induction rules have conclusions
  1845 of the form "P foo bar" instead of "P <foo, bar>".
  1846 
  1847 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1848 been renamed to "below".  The name "below" now replaces "less" in many
  1849 theorem names.  (Legacy theorem names using "less" are still supported
  1850 as well.)
  1851 
  1852 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1853 patterns can be used to generate strictness rules, or to make
  1854 functions more strict (much like the bang-patterns supported by the
  1855 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1856 examples.
  1857 
  1858 
  1859 *** ML ***
  1860 
  1861 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1862 errors and run-time exceptions, including detailed source positions.
  1863 
  1864 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1865 identified entries, with some additional information such as source
  1866 position, logical grouping etc.
  1867 
  1868 * Theory and context data is now introduced by the simplified and
  1869 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1870 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1871 copy operation) is still available for some time.
  1872 
  1873 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1874 provides a high-level programming interface to synchronized state
  1875 variables with atomic update.  This works via pure function
  1876 application within a critical section -- its runtime should be as
  1877 short as possible; beware of deadlocks if critical code is nested,
  1878 either directly or indirectly via other synchronized variables!
  1879 
  1880 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1881 wraps raw ML references, explicitly indicating their non-thread-safe
  1882 behaviour.  The Isar toplevel keeps this structure open, to
  1883 accommodate Proof General as well as quick and dirty interactive
  1884 experiments with references.
  1885 
  1886 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1887 parallel tactical reasoning.
  1888 
  1889 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1890 are similar to SUBPROOF, but are slightly more flexible: only the
  1891 specified parts of the subgoal are imported into the context, and the
  1892 body tactic may introduce new subgoals and schematic variables.
  1893 
  1894 * Old tactical METAHYPS, which does not observe the proof context, has
  1895 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1896 or Subgoal.FOCUS etc.
  1897 
  1898 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1899 functors have their own ML name space there is no point to mark them
  1900 separately.)  Minor INCOMPATIBILITY.
  1901 
  1902 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1903 
  1904 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1905 INCOMPATIBILITY.
  1906 
  1907 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1908 mode, which avoids critical setmp.
  1909 
  1910 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1911 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1912 Attrib/Method.setup introduced in Isabelle2009.
  1913 
  1914 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1915 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1916 last resort.  INCOMPATIBILITY.
  1917 
  1918 * Display.pretty_thm now requires a proper context (cf. former
  1919 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1920 or even Display.pretty_thm_without_context as last resort.
  1921 INCOMPATIBILITY.
  1922 
  1923 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1924 Syntax.pretty_typ/term directly, preferably with proper context
  1925 instead of global theory.
  1926 
  1927 
  1928 *** System ***
  1929 
  1930 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1931 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1932 usedir option -q.
  1933 
  1934 * Support for additional "Isabelle components" via etc/components, see
  1935 also the system manual.
  1936 
  1937 * The isabelle makeall tool now operates on all components with
  1938 IsaMakefile, not just hardwired "logics".
  1939 
  1940 * Removed "compress" option from isabelle-process and isabelle usedir;
  1941 this is always enabled.
  1942 
  1943 * Discontinued support for Poly/ML 4.x versions.
  1944 
  1945 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  1946 on a given logic image.  This requires the lighttpd webserver and is
  1947 currently supported on Linux only.
  1948 
  1949 
  1950 
  1951 New in Isabelle2009 (April 2009)
  1952 --------------------------------
  1953 
  1954 *** General ***
  1955 
  1956 * Simplified main Isabelle executables, with less surprises on
  1957 case-insensitive file-systems (such as Mac OS).
  1958 
  1959   - The main Isabelle tool wrapper is now called "isabelle" instead of
  1960     "isatool."
  1961 
  1962   - The former "isabelle" alias for "isabelle-process" has been
  1963     removed (should rarely occur to regular users).
  1964 
  1965   - The former "isabelle-interface" and its alias "Isabelle" have been
  1966     removed (interfaces are now regular Isabelle tools).
  1967 
  1968 Within scripts and make files, the Isabelle environment variables
  1969 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  1970 respectively.  (The latter are still available as legacy feature.)
  1971 
  1972 The old isabelle-interface wrapper could react in confusing ways if
  1973 the interface was uninstalled or changed otherwise.  Individual
  1974 interface tool configuration is now more explicit, see also the
  1975 Isabelle system manual.  In particular, Proof General is now available
  1976 via "isabelle emacs".
  1977 
  1978 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  1979 purge installed copies of Isabelle executables and re-run "isabelle
  1980 install -p ...", or use symlinks.
  1981 
  1982 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  1983 old ~/isabelle, which was slightly non-standard and apt to cause
  1984 surprises on case-insensitive file-systems (such as Mac OS).
  1985 
  1986 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  1987 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  1988 care is required when using older releases of Isabelle.  Note that
  1989 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  1990 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  1991 
  1992 * Proofs of fully specified statements are run in parallel on
  1993 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  1994 a regular 4-core machine, if the initial heap space is made reasonably
  1995 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  1996 
  1997 * The main reference manuals ("isar-ref", "implementation", and
  1998 "system") have been updated and extended.  Formally checked references
  1999 as hyperlinks are now available uniformly.
  2000 
  2001 
  2002 *** Pure ***
  2003 
  2004 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  2005 respects.  The most important changes are listed below.  See the
  2006 Tutorial on Locales ("locales" manual) for details.
  2007 
  2008 - In locale expressions, instantiation replaces renaming.  Parameters
  2009 must be declared in a for clause.  To aid compatibility with previous
  2010 parameter inheritance, in locale declarations, parameters that are not
  2011 'touched' (instantiation position "_" or omitted) are implicitly added
  2012 with their syntax at the beginning of the for clause.
  2013 
  2014 - Syntax from abbreviations and definitions in locales is available in
  2015 locale expressions and context elements.  The latter is particularly
  2016 useful in locale declarations.
  2017 
  2018 - More flexible mechanisms to qualify names generated by locale
  2019 expressions.  Qualifiers (prefixes) may be specified in locale
  2020 expressions, and can be marked as mandatory (syntax: "name!:") or
  2021 optional (syntax "name?:").  The default depends for plain "name:"
  2022 depends on the situation where a locale expression is used: in
  2023 commands 'locale' and 'sublocale' prefixes are optional, in
  2024 'interpretation' and 'interpret' prefixes are mandatory.  The old
  2025 implicit qualifiers derived from the parameter names of a locale are
  2026 no longer generated.
  2027 
  2028 - Command "sublocale l < e" replaces "interpretation l < e".  The
  2029 instantiation clause in "interpretation" and "interpret" (square
  2030 brackets) is no longer available.  Use locale expressions.
  2031 
  2032 - When converting proof scripts, mandatory qualifiers in
  2033 'interpretation' and 'interpret' should be retained by default, even
  2034 if this is an INCOMPATIBILITY compared to former behavior.  In the
  2035 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  2036 in locale expressions range over a single locale instance only.
  2037 
  2038 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  2039 In existing theorem specifications replace the includes element by the
  2040 respective context elements of the included locale, omitting those
  2041 that are already present in the theorem specification.  Multiple
  2042 assume elements of a locale should be replaced by a single one
  2043 involving the locale predicate.  In the proof body, declarations (most
  2044 notably theorems) may be regained by interpreting the respective
  2045 locales in the proof context as required (command "interpret").
  2046 
  2047 If using "includes" in replacement of a target solely because the
  2048 parameter types in the theorem are not as general as in the target,
  2049 consider declaring a new locale with additional type constraints on
  2050 the parameters (context element "constrains").
  2051 
  2052 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2053 
  2054 - Locale interpretation commands no longer attempt to simplify goal.
  2055 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2056 methods intro_locales and unfold_locales to clarify.
  2057 
  2058 - Locale interpretation commands no longer accept interpretation
  2059 attributes.  INCOMPATIBILITY.
  2060 
  2061 * Class declaration: so-called "base sort" must not be given in import
  2062 list any longer, but is inferred from the specification.  Particularly
  2063 in HOL, write
  2064 
  2065     class foo = ...
  2066 
  2067 instead of
  2068 
  2069     class foo = type + ...
  2070 
  2071 * Class target: global versions of theorems stemming do not carry a
  2072 parameter prefix any longer.  INCOMPATIBILITY.
  2073 
  2074 * Class 'instance' command no longer accepts attached definitions.
  2075 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2076 
  2077 * Recovered hiding of consts, which was accidentally broken in
  2078 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2079 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2080 
  2081 * Slightly more coherent Pure syntax, with updated documentation in
  2082 isar-ref manual.  Removed locales meta_term_syntax and
  2083 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2084 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2085 directly in regular applications.
  2086 
  2087 * There is a new syntactic category "float_const" for signed decimal
  2088 fractions (e.g. 123.45 or -123.45).
  2089 
  2090 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2091 interface with 'setup' command instead.
  2092 
  2093 * Command 'local_setup' is similar to 'setup', but operates on a local
  2094 theory context.
  2095 
  2096 * The 'axiomatization' command now only works within a global theory
  2097 context.  INCOMPATIBILITY.
  2098 
  2099 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2100 hypotheses.  Sorts required in the course of reasoning need to be
  2101 covered by the constraints in the initial statement, completed by the
  2102 type instance information of the background theory.  Non-trivial sort
  2103 hypotheses, which rarely occur in practice, may be specified via
  2104 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2105 
  2106   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2107 
  2108 The result contains an implicit sort hypotheses as before --
  2109 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2110 normalization.
  2111 
  2112 * Generalized Isar history, with support for linear undo, direct state
  2113 addressing etc.
  2114 
  2115 * Changed defaults for unify configuration options:
  2116 
  2117   unify_trace_bound = 50 (formerly 25)
  2118   unify_search_bound = 60 (formerly 30)
  2119 
  2120 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2121 
  2122   a) On theory merge, the last set of code equations for a particular
  2123      constant is taken (in accordance with the policy applied by other
  2124      parts of the code generator framework).
  2125 
  2126   b) Code equations stemming from explicit declarations (e.g. code
  2127      attribute) gain priority over default code equations stemming
  2128      from definition, primrec, fun etc.
  2129 
  2130 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2131 
  2132 * Unified theorem tables for both code generators.  Thus [code
  2133 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2134 
  2135 * Command 'find_consts' searches for constants based on type and name
  2136 patterns, e.g.
  2137 
  2138     find_consts "_ => bool"
  2139 
  2140 By default, matching is against subtypes, but it may be restricted to
  2141 the whole type.  Searching by name is possible.  Multiple queries are
  2142 conjunctive and queries may be negated by prefixing them with a
  2143 hyphen:
  2144 
  2145     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2146 
  2147 * New 'find_theorems' criterion "solves" matches theorems that
  2148 directly solve the current goal (modulo higher-order unification).
  2149 
  2150 * Auto solve feature for main theorem statements: whenever a new goal
  2151 is stated, "find_theorems solves" is called; any theorems that could
  2152 solve the lemma directly are listed as part of the goal state.
  2153 Cf. associated options in Proof General Isabelle settings menu,
  2154 enabled by default, with reasonable timeout for pathological cases of
  2155 higher-order unification.
  2156 
  2157 
  2158 *** Document preparation ***
  2159 
  2160 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2161 demanding keyword 'by' and supporting the full method expression
  2162 syntax just like the Isar command 'by'.
  2163 
  2164 
  2165 *** HOL ***
  2166 
  2167 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2168 points Main and Complex_Main remain as before.
  2169 
  2170 * Logic image HOL-Plain provides a minimal HOL with the most important
  2171 tools available (inductive, datatype, primrec, ...).  This facilitates
  2172 experimentation and tool development.  Note that user applications
  2173 (and library theories) should never refer to anything below theory
  2174 Main, as before.
  2175 
  2176 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2177 experimentation due to shorter build times.
  2178 
  2179 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2180 were previously part of former HOL-Complex.  Entry point Hyperreal
  2181 remains valid, but theories formerly using Complex_Main should now use
  2182 new entry point Hypercomplex.
  2183 
  2184 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2185 Posix processes.  Avoids potentially expensive forking of the ML
  2186 process.  New thread-based implementation also works on non-Unix
  2187 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2188 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2189 commands are covered in the isar-ref manual.
  2190 
  2191 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2192 sledgehammer without local ATP installation (Vampire etc.). Other
  2193 provers may be included via suitable ML wrappers, see also
  2194 src/HOL/ATP_Linkup.thy.
  2195 
  2196 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2197 menu.
  2198 
  2199 * The metis method no longer fails because the theorem is too trivial
  2200 (contains the empty clause).
  2201 
  2202 * The metis method now fails in the usual manner, rather than raising
  2203 an exception, if it determines that it cannot prove the theorem.
  2204 
  2205 * Method "coherent" implements a prover for coherent logic (see also
  2206 src/Tools/coherent.ML).
  2207 
  2208 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2209 "undefined" is the right choice to replace "arbitrary", though
  2210 logically there is no difference.  INCOMPATIBILITY.
  2211 
  2212 * Command "value" now integrates different evaluation mechanisms.  The
  2213 result of the first successful evaluation mechanism is printed.  In
  2214 square brackets a particular named evaluation mechanisms may be
  2215 specified (currently, [SML], [code] or [nbe]).  See further
  2216 src/HOL/ex/Eval_Examples.thy.
  2217 
  2218 * Normalization by evaluation now allows non-leftlinear equations.
  2219 Declare with attribute [code nbe].
  2220 
  2221 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2222 as the structured Isar versions "cases" and "induct", cf. the
  2223 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2224 are now presented as a list of individual projections
  2225 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2226 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2227 rare situations a different rule is selected --- notably nested tuple
  2228 elimination instead of former prod.exhaust: use explicit (case_tac t
  2229 rule: prod.exhaust) here.
  2230 
  2231 * Attributes "cases", "induct", "coinduct" support "del" option.
  2232 
  2233 * Removed fact "case_split_thm", which duplicates "case_split".
  2234 
  2235 * The option datatype has been moved to a new theory Option.  Renamed
  2236 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2237 
  2238 * New predicate "strict_mono" classifies strict functions on partial
  2239 orders.  With strict functions on linear orders, reasoning about
  2240 (in)equalities is facilitated by theorems "strict_mono_eq",
  2241 "strict_mono_less_eq" and "strict_mono_less".
  2242 
  2243 * Some set operations are now proper qualified constants with
  2244 authentic syntax.  INCOMPATIBILITY:
  2245 
  2246     op Int ~>   Set.Int
  2247     op Un ~>    Set.Un
  2248     INTER ~>    Set.INTER
  2249     UNION ~>    Set.UNION
  2250     Inter ~>    Set.Inter
  2251     Union ~>    Set.Union
  2252     {} ~>       Set.empty
  2253     UNIV ~>     Set.UNIV
  2254 
  2255 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2256 theory Set.
  2257 
  2258 * Auxiliary class "itself" has disappeared -- classes without any
  2259 parameter are treated as expected by the 'class' command.
  2260 
  2261 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2262 
  2263 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2264 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2265 
  2266 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2267 method "approximation".  It proves formulas on real values by using
  2268 interval arithmetic.  In the formulas are also the transcendental
  2269 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2270 allowed. For examples see
  2271 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2272 
  2273 * Theory "Reflection" now resides in HOL/Library.
  2274 
  2275 * Entry point to Word library now simply named "Word".
  2276 INCOMPATIBILITY.
  2277 
  2278 * Made source layout more coherent with logical distribution
  2279 structure:
  2280 
  2281     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2282     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2283     src/HOL/Library/GCD.thy ~> src/HOL/
  2284     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2285     src/HOL/Library/Parity.thy ~> src/HOL/
  2286     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2287     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2288     src/HOL/Real/Lubs.thy ~> src/HOL/
  2289     src/HOL/Real/PReal.thy ~> src/HOL/
  2290     src/HOL/Real/Rational.thy ~> src/HOL/
  2291     src/HOL/Real/RComplete.thy ~> src/HOL/
  2292     src/HOL/Real/RealDef.thy ~> src/HOL/
  2293     src/HOL/Real/RealPow.thy ~> src/HOL/
  2294     src/HOL/Real/Real.thy ~> src/HOL/
  2295     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2296     src/HOL/Complex/Complex.thy ~> src/HOL/
  2297     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2298     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2299     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2300     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2301     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2302     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2303     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2304     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2305     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2306     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2307     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2308     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2309     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2310     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2311     src/HOL/Real/Float ~> src/HOL/Library/
  2312     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2313     src/HOL/Real/RealVector.thy ~> src/HOL/
  2314 
  2315     src/HOL/arith_data.ML ~> src/HOL/Tools
  2316     src/HOL/hologic.ML ~> src/HOL/Tools
  2317     src/HOL/simpdata.ML ~> src/HOL/Tools
  2318     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2319     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2320     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2321     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2322     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2323     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2324     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2325 
  2326     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2327     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2328     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2329     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2330     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2331     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2332 
  2333 * If methods "eval" and "evaluation" encounter a structured proof
  2334 state with !!/==>, only the conclusion is evaluated to True (if
  2335 possible), avoiding strange error messages.
  2336 
  2337 * Method "sizechange" automates termination proofs using (a
  2338 modification of) the size-change principle.  Requires SAT solver.  See
  2339 src/HOL/ex/Termination.thy for examples.
  2340 
  2341 * Simplifier: simproc for let expressions now unfolds if bound
  2342 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2343 
  2344 * Method "arith": Linear arithmetic now ignores all inequalities when
  2345 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2346 
  2347 * New attribute "arith" for facts that should always be used
  2348 automatically by arithmetic. It is intended to be used locally in
  2349 proofs, e.g.
  2350 
  2351   assumes [arith]: "x > 0"
  2352 
  2353 Global usage is discouraged because of possible performance impact.
  2354 
  2355 * New classes "top" and "bot" with corresponding operations "top" and
  2356 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2357 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2358 
  2359 * Changed definition lemma "less_fun_def" in order to provide an
  2360 instance for preorders on functions; use lemma "less_le" instead.
  2361 INCOMPATIBILITY.
  2362 
  2363 * Theory Orderings: class "wellorder" moved here, with explicit
  2364 induction rule "less_induct" as assumption.  For instantiation of
  2365 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2366 INCOMPATIBILITY.
  2367 
  2368 * Theory Orderings: added class "preorder" as superclass of "order".
  2369 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2370 etc. slightly changed.  Some theorems named order_class.* now named
  2371 preorder_class.*.
  2372 
  2373 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2374 "diag" to "Id_on".
  2375 
  2376 * Theory Finite_Set: added a new fold combinator of type
  2377 
  2378   ('a => 'b => 'b) => 'b => 'a set => 'b
  2379 
  2380 Occasionally this is more convenient than the old fold combinator
  2381 which is now defined in terms of the new one and renamed to
  2382 fold_image.
  2383 
  2384 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2385 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2386 extended with further lemmas!).  At the moment both still exist but
  2387 the former will disappear at some point.
  2388 
  2389 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2390 class recpower.  Type-specific simp rules for various recpower types
  2391 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2392 
  2393 rat_power_0    -> power_0
  2394 rat_power_Suc  -> power_Suc
  2395 realpow_0      -> power_0
  2396 realpow_Suc    -> power_Suc
  2397 complexpow_0   -> power_0
  2398 complexpow_Suc -> power_Suc
  2399 power_poly_0   -> power_0
  2400 power_poly_Suc -> power_Suc
  2401 
  2402 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2403 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2404 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2405 of lemmas from Divides has been generalized from nat to class
  2406 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2407 renames resulting from duplicate elimination:
  2408 
  2409     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2410     zero_dvd_iff ~>         dvd_0_left_iff
  2411     dvd_0 ~>                dvd_0_right
  2412     DIVISION_BY_ZERO_DIV ~> div_by_0
  2413     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2414     mult_div ~>             div_mult_self2_is_id
  2415     mult_mod ~>             mod_mult_self2_is_0
  2416 
  2417 * Theory IntDiv: removed many lemmas that are instances of class-based
  2418 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2419 rename old lemmas as follows:
  2420 
  2421 dvd_diff               -> nat_dvd_diff
  2422 dvd_zminus_iff         -> dvd_minus_iff
  2423 mod_add1_eq            -> mod_add_eq
  2424 mod_mult1_eq           -> mod_mult_right_eq
  2425 mod_mult1_eq'          -> mod_mult_left_eq
  2426 mod_mult_distrib_mod   -> mod_mult_eq
  2427 nat_mod_add_left_eq    -> mod_add_left_eq
  2428 nat_mod_add_right_eq   -> mod_add_right_eq
  2429 nat_mod_div_trivial    -> mod_div_trivial
  2430 nat_mod_mod_trivial    -> mod_mod_trivial
  2431 zdiv_zadd_self1        -> div_add_self1
  2432 zdiv_zadd_self2        -> div_add_self2
  2433 zdiv_zmult_self1       -> div_mult_self2_is_id
  2434 zdiv_zmult_self2       -> div_mult_self1_is_id
  2435 zdvd_triv_left         -> dvd_triv_left
  2436 zdvd_triv_right        -> dvd_triv_right
  2437 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2438 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2439 zmod_zadd_left_eq      -> mod_add_left_eq
  2440 zmod_zadd_right_eq     -> mod_add_right_eq
  2441 zmod_zadd_self1        -> mod_add_self1
  2442 zmod_zadd_self2        -> mod_add_self2
  2443 zmod_zadd1_eq          -> mod_add_eq
  2444 zmod_zdiff1_eq         -> mod_diff_eq
  2445 zmod_zdvd_zmod         -> mod_mod_cancel
  2446 zmod_zmod_cancel       -> mod_mod_cancel
  2447 zmod_zmult_self1       -> mod_mult_self2_is_0
  2448 zmod_zmult_self2       -> mod_mult_self1_is_0
  2449 zmod_1                 -> mod_by_1
  2450 zdiv_1                 -> div_by_1
  2451 zdvd_abs1              -> abs_dvd_iff
  2452 zdvd_abs2              -> dvd_abs_iff
  2453 zdvd_refl              -> dvd_refl
  2454 zdvd_trans             -> dvd_trans
  2455 zdvd_zadd              -> dvd_add
  2456 zdvd_zdiff             -> dvd_diff
  2457 zdvd_zminus_iff        -> dvd_minus_iff
  2458 zdvd_zminus2_iff       -> minus_dvd_iff
  2459 zdvd_zmultD            -> dvd_mult_right
  2460 zdvd_zmultD2           -> dvd_mult_left
  2461 zdvd_zmult_mono        -> mult_dvd_mono
  2462 zdvd_0_right           -> dvd_0_right
  2463 zdvd_0_left            -> dvd_0_left_iff
  2464 zdvd_1_left            -> one_dvd
  2465 zminus_dvd_iff         -> minus_dvd_iff
  2466 
  2467 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2468 
  2469 * The real numbers offer decimal input syntax: 12.34 is translated
  2470 into 1234/10^2. This translation is not reversed upon output.
  2471 
  2472 * Theory Library/Polynomial defines an abstract type 'a poly of
  2473 univariate polynomials with coefficients of type 'a.  In addition to
  2474 the standard ring operations, it also supports div and mod.  Code
  2475 generation is also supported, using list-style constructors.
  2476 
  2477 * Theory Library/Inner_Product defines a class of real_inner for real
  2478 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2479 => real.  Class real_inner is a subclass of real_normed_vector from
  2480 theory RealVector.
  2481 
  2482 * Theory Library/Product_Vector provides instances for the product
  2483 type 'a * 'b of several classes from RealVector and Inner_Product.
  2484 Definitions of addition, subtraction, scalar multiplication, norms,
  2485 and inner products are included.
  2486 
  2487 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2488 addition to the field operations, numerals and case syntax are also
  2489 supported.
  2490 
  2491 * Theory Library/Diagonalize provides constructive version of Cantor's
  2492 first diagonalization argument.
  2493 
  2494 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2495 zlcm (for int); carried together from various gcd/lcm developements in
  2496 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2497 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2498 may recover tupled syntax as follows:
  2499 
  2500     hide (open) const gcd
  2501     abbreviation gcd where
  2502       "gcd == (%(a, b). GCD.gcd a b)"
  2503     notation (output)
  2504       GCD.gcd ("gcd '(_, _')")
  2505 
  2506 The same works for lcm, zgcd, zlcm.
  2507 
  2508 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2509 instantiations for algebraic structures.  Removed some duplicate
  2510 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2511 
  2512 * ML antiquotation @{code} takes a constant as argument and generates
  2513 corresponding code in background and inserts name of the corresponding
  2514 resulting ML value/function/datatype constructor binding in place.
  2515 All occurrences of @{code} with a single ML block are generated
  2516 simultaneously.  Provides a generic and safe interface for
  2517 instrumentalizing code generation.  See
  2518 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2519 In future you ought to refrain from ad-hoc compiling generated SML
  2520 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2521 cannot refer to constants for which user-defined serializations are
  2522 set.  Refer to the corresponding ML counterpart directly in that
  2523 cases.
  2524 
  2525 * Command 'rep_datatype': instead of theorem names the command now
  2526 takes a list of terms denoting the constructors of the type to be
  2527 represented as datatype.  The characteristic theorems have to be
  2528 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2529 have disappeared in favour of existing ones:
  2530 
  2531     unit_induct                 ~> unit.induct
  2532     prod_induct                 ~> prod.induct
  2533     sum_induct                  ~> sum.induct
  2534     Suc_Suc_eq                  ~> nat.inject
  2535     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2536 
  2537 
  2538 *** HOL-Algebra ***
  2539 
  2540 * New locales for orders and lattices where the equivalence relation
  2541 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2542 locales use a record structure with field eq for the equivalence.
  2543 
  2544 * New theory of factorial domains.
  2545 
  2546 * Units_l_inv and Units_r_inv are now simp rules by default.
  2547 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2548 and/or r_inv will now also require deletion of these lemmas.
  2549 
  2550 * Renamed the following theorems, INCOMPATIBILITY:
  2551 
  2552 UpperD ~> Upper_memD
  2553 LowerD ~> Lower_memD
  2554 least_carrier ~> least_closed
  2555 greatest_carrier ~> greatest_closed
  2556 greatest_Lower_above ~> greatest_Lower_below
  2557 one_zero ~> carrier_one_zero
  2558 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2559 
  2560 
  2561 *** HOL-Nominal ***
  2562 
  2563 * Nominal datatypes can now contain type-variables.
  2564 
  2565 * Commands 'nominal_inductive' and 'equivariance' work with local
  2566 theory targets.
  2567 
  2568 * Nominal primrec can now works with local theory targets and its
  2569 specification syntax now conforms to the general format as seen in
  2570 'inductive' etc.
  2571 
  2572 * Method "perm_simp" honours the standard simplifier attributes
  2573 (no_asm), (no_asm_use) etc.
  2574 
  2575 * The new predicate #* is defined like freshness, except that on the
  2576 left hand side can be a set or list of atoms.
  2577 
  2578 * Experimental command 'nominal_inductive2' derives strong induction
  2579 principles for inductive definitions.  In contrast to
  2580 'nominal_inductive', which can only deal with a fixed number of
  2581 binders, it can deal with arbitrary expressions standing for sets of
  2582 atoms to be avoided.  The only inductive definition we have at the
  2583 moment that needs this generalisation is the typing rule for Lets in
  2584 the algorithm W:
  2585 
  2586  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2587  -----------------------------------------------------------------
  2588          Gamma |- Let x be t1 in t2 : T2
  2589 
  2590 In this rule one wants to avoid all the binders that are introduced by
  2591 "close Gamma T1".  We are looking for other examples where this
  2592 feature might be useful.  Please let us know.
  2593 
  2594 
  2595 *** HOLCF ***
  2596 
  2597 * Reimplemented the simplification procedure for proving continuity
  2598 subgoals.  The new simproc is extensible; users can declare additional
  2599 continuity introduction rules with the attribute [cont2cont].
  2600 
  2601 * The continuity simproc now uses a different introduction rule for
  2602 solving continuity subgoals on terms with lambda abstractions.  In
  2603 some rare cases the new simproc may fail to solve subgoals that the
  2604 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2605 Potential INCOMPATIBILITY.
  2606 
  2607 * Command 'fixrec': specification syntax now conforms to the general
  2608 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2609 examples.  INCOMPATIBILITY.
  2610 
  2611 
  2612 *** ZF ***
  2613 
  2614 * Proof of Zorn's Lemma for partial orders.
  2615 
  2616 
  2617 *** ML ***
  2618 
  2619 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2620 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2621 depends on multithreading, so timouts will not work before Poly/ML
  2622 5.2.1!
  2623 
  2624 * High-level support for concurrent ML programming, see
  2625 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2626 particularly convenient to organize independent functional
  2627 computations.  The concept of "synchronized variables" provides a
  2628 higher-order interface for components with shared state, avoiding the
  2629 delicate details of mutexes and condition variables.  (Requires
  2630 Poly/ML 5.2.1 or later.)
  2631 
  2632 * ML bindings produced via Isar commands are stored within the Isar
  2633 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2634 become thread-safe and work with undo as expected (concerning
  2635 top-level bindings, not side-effects on global references).
  2636 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2637 compiler at runtime; really global bindings need to be given outside a
  2638 theory.  (Requires Poly/ML 5.2 or later.)
  2639 
  2640 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2641 context.  Top-level ML bindings are stored within the proof context in
  2642 a purely sequential fashion, disregarding the nested proof structure.
  2643 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2644 proof.  (Requires Poly/ML 5.2 or later.)
  2645 
  2646 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2647 and Method.setup, as well as Isar commands 'attribute_setup' and
  2648 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2649 existing code accordingly, or use plain 'setup' together with old
  2650 Method.add_method.
  2651 
  2652 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2653 to 'a -> thm, while results are always tagged with an authentic oracle
  2654 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2655 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2656 accordingly.  Note that extra performance may be gained by producing
  2657 the cterm carefully, avoiding slow Thm.cterm_of.
  2658 
  2659 * Simplified interface for defining document antiquotations via
  2660 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2661 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2662 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2663 examples.
  2664 
  2665 * More systematic treatment of long names, abstract name bindings, and
  2666 name space operations.  Basic operations on qualified names have been
  2667 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2668 Long_Name.append.  Old type bstring has been mostly replaced by
  2669 abstract type binding (see structure Binding), which supports precise
  2670 qualification by packages and local theory targets, as well as proper
  2671 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2672 bstring values into Binding.name, or better pass through abstract
  2673 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2674 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2675 
  2676 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2677 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2678 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2679 
  2680 * Disposed old type and term read functions (Sign.read_def_typ,
  2681 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2682 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2683 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2684 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2685 resort for legacy applications.
  2686 
  2687 * Disposed old declarations, tactics, tactic combinators that refer to
  2688 the simpset or claset of an implicit theory (such as Addsimps,
  2689 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2690 embedded ML text, or local_simpset_of with a proper context passed as
  2691 explicit runtime argument.
  2692 
  2693 * Rules and tactics that read instantiations (read_instantiate,
  2694 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2695 context, which is required for parsing and type-checking.  Moreover,
  2696 the variables are specified as plain indexnames, not string encodings
  2697 thereof.  INCOMPATIBILITY.
  2698 
  2699 * Generic Toplevel.add_hook interface allows to analyze the result of
  2700 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2701 for theorem dependency output of transactions resulting in a new
  2702 theory state.
  2703 
  2704 * ML antiquotations: block-structured compilation context indicated by
  2705 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2706 
  2707   @{binding name}                         - basic name binding
  2708   @{let ?pat = term}                      - term abbreviation (HO matching)
  2709   @{note name = fact}                     - fact abbreviation
  2710   @{thm fact}                             - singleton fact (with attributes)
  2711   @{thms fact}                            - general fact (with attributes)
  2712   @{lemma prop by method}                 - singleton goal
  2713   @{lemma prop by meth1 meth2}            - singleton goal
  2714   @{lemma prop1 ... propN by method}      - general goal
  2715   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2716   @{lemma (open) ...}                     - open derivation
  2717 
  2718 
  2719 *** System ***
  2720 
  2721 * The Isabelle "emacs" tool provides a specific interface to invoke
  2722 Proof General / Emacs, with more explicit failure if that is not
  2723 installed (the old isabelle-interface script silently falls back on
  2724 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2725 installation location of the Proof General distribution.
  2726 
  2727 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2728 the Isabelle process into a JVM/Scala application.  See
  2729 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2730 process wrapper has been discontinued.)
  2731 
  2732 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2733 
  2734 * Various status messages (with exact source position information) are
  2735 emitted, if proper markup print mode is enabled.  This allows
  2736 user-interface components to provide detailed feedback on internal
  2737 prover operations.
  2738 
  2739 
  2740 
  2741 New in Isabelle2008 (June 2008)
  2742 -------------------------------
  2743 
  2744 *** General ***
  2745 
  2746 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2747 and updated, with formally checked references as hyperlinks.
  2748 
  2749 * Theory loader: use_thy (and similar operations) no longer set the
  2750 implicit ML context, which was occasionally hard to predict and in
  2751 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2752 provides a proper context already.
  2753 
  2754 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2755 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2756 'use' within a theory file will do the job.
  2757 
  2758 * Name space merge now observes canonical order, i.e. the second space
  2759 is inserted into the first one, while existing entries in the first
  2760 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2761 swap theory imports.
  2762 
  2763 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2764 INCOMPATIBILITY in identifier syntax etc.
  2765 
  2766 * Outer syntax: string tokens no longer admit escaped white space,
  2767 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2768 white space without escapes.
  2769 
  2770 * Outer syntax: string tokens may contain arbitrary character codes
  2771 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2772 "foo_bar".
  2773 
  2774 
  2775 *** Pure ***
  2776 
  2777 * Context-dependent token translations.  Default setup reverts locally
  2778 fixed variables, and adds hilite markup for undeclared frees.
  2779 
  2780 * Unused theorems can be found using the new command 'unused_thms'.
  2781 There are three ways of invoking it:
  2782 
  2783 (1) unused_thms
  2784      Only finds unused theorems in the current theory.
  2785 
  2786 (2) unused_thms thy_1 ... thy_n -
  2787      Finds unused theorems in the current theory and all of its ancestors,
  2788      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2789 
  2790 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2791      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2792      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2793      their ancestors.
  2794 
  2795 In order to increase the readability of the list produced by
  2796 unused_thms, theorems that have been created by a particular instance
  2797 of a theory command such as 'inductive' or 'function' are considered
  2798 to belong to the same "group", meaning that if at least one theorem in
  2799 this group is used, the other theorems in the same group are no longer
  2800 reported as unused.  Moreover, if all theorems in the group are
  2801 unused, only one theorem in the group is displayed.
  2802 
  2803 Note that proof objects have to be switched on in order for
  2804 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2805 usually the case when using Proof General with the default settings).
  2806 
  2807 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2808 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2809 duplicate fact bindings, or even accidental fact duplications.  Note
  2810 that tools may maintain dynamically scoped facts systematically, using
  2811 PureThy.add_thms_dynamic.
  2812 
  2813 * Command 'hide' now allows to hide from "fact" name space as well.
  2814 
  2815 * Eliminated destructive theorem database, simpset, claset, and
  2816 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2817 update of theories within ML code.
  2818 
  2819 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2820 INCOMPATIBILITY, object-logics depending on former Pure require
  2821 additional setup PureThy.old_appl_syntax_setup; object-logics
  2822 depending on former CPure need to refer to Pure.
  2823 
  2824 * Commands 'use' and 'ML' are now purely functional, operating on
  2825 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2826 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2827 INCOMPATIBILITY.
  2828 
  2829 * Command 'setup': discontinued implicit version with ML reference.
  2830 
  2831 * Instantiation target allows for simultaneous specification of class
  2832 instance operations together with an instantiation proof.
  2833 Type-checking phase allows to refer to class operations uniformly.
  2834 See src/HOL/Complex/Complex.thy for an Isar example and
  2835 src/HOL/Library/Eval.thy for an ML example.
  2836 
  2837 * Indexing of literal facts: be more serious about including only
  2838 facts from the visible specification/proof context, but not the
  2839 background context (locale etc.).  Affects `prop` notation and method
  2840 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2841 situations.
  2842 
  2843 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2844 "(open)" option, which used to expose internal bound variables to the
  2845 proof text.
  2846 
  2847 * Isar statements: removed obsolete case "rule_context".
  2848 INCOMPATIBILITY, better use explicit fixes/assumes.
  2849 
  2850 * Locale proofs: default proof step now includes 'unfold_locales';
  2851 hence 'proof' without argument may be used to unfold locale
  2852 predicates.
  2853 
  2854 
  2855 *** Document preparation ***
  2856 
  2857 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2858 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2859 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2860 spot); renamed link color from "darkblue" to "linkcolor" (default
  2861 value unchanged, can be redefined via \definecolor); no longer sets
  2862 "a4paper" option (unnecessary or even intrusive).
  2863 
  2864 * Antiquotation @{lemma A method} proves proposition A by the given
  2865 method (either a method name or a method name plus (optional) method
  2866 arguments in parentheses) and prints A just like @{prop A}.
  2867 
  2868 
  2869 *** HOL ***
  2870 
  2871 * New primrec package.  Specification syntax conforms in style to
  2872 definition/function/....  No separate induction rule is provided.  The
  2873 "primrec" command distinguishes old-style and new-style specifications
  2874 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2875 When adjusting theories, beware: constants stemming from new-style
  2876 primrec specifications have authentic syntax.
  2877 
  2878 * Metis prover is now an order of magnitude faster, and also works
  2879 with multithreading.
  2880 
  2881 * Metis: the maximum number of clauses that can be produced from a
  2882 theorem is now given by the attribute max_clauses.  Theorems that
  2883 exceed this number are ignored, with a warning printed.
  2884 
  2885 * Sledgehammer no longer produces structured proofs by default. To
  2886 enable, declare [[sledgehammer_full = true]].  Attributes
  2887 reconstruction_modulus, reconstruction_sorts renamed
  2888 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2889 
  2890 * Method "induct_scheme" derives user-specified induction rules
  2891 from well-founded induction and completeness of patterns. This factors
  2892 out some operations that are done internally by the function package
  2893 and makes them available separately.  See
  2894 src/HOL/ex/Induction_Scheme.thy for examples.
  2895 
  2896 * More flexible generation of measure functions for termination
  2897 proofs: Measure functions can be declared by proving a rule of the
  2898 form "is_measure f" and giving it the [measure_function] attribute.
  2899 The "is_measure" predicate is logically meaningless (always true), and
  2900 just guides the heuristic.  To find suitable measure functions, the
  2901 termination prover sets up the goal "is_measure ?f" of the appropriate
  2902 type and generates all solutions by prolog-style backwards proof using
  2903 the declared rules.
  2904 
  2905 This setup also deals with rules like 
  2906 
  2907   "is_measure f ==> is_measure (list_size f)"
  2908 
  2909 which accommodates nested datatypes that recurse through lists.
  2910 Similar rules are predeclared for products and option types.
  2911 
  2912 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2913 
  2914   INCOMPATIBILITIES:
  2915 
  2916   - Definitions of overloaded constants on sets have to be replaced by
  2917     definitions on => and bool.
  2918 
  2919   - Some definitions of overloaded operators on sets can now be proved
  2920     using the definitions of the operators on => and bool.  Therefore,
  2921     the following theorems have been renamed:
  2922 
  2923       subset_def   -> subset_eq
  2924       psubset_def  -> psubset_eq
  2925       set_diff_def -> set_diff_eq
  2926       Compl_def    -> Compl_eq
  2927       Sup_set_def  -> Sup_set_eq
  2928       Inf_set_def  -> Inf_set_eq
  2929       sup_set_def  -> sup_set_eq
  2930       inf_set_def  -> inf_set_eq
  2931 
  2932   - Due to the incompleteness of the HO unification algorithm, some
  2933     rules such as subst may require manual instantiation, if some of
  2934     the unknowns in the rule is a set.
  2935 
  2936   - Higher order unification and forward proofs:
  2937     The proof pattern
  2938 
  2939       have "P (S::'a set)" <...>
  2940       then have "EX S. P S" ..
  2941 
  2942     no longer works (due to the incompleteness of the HO unification
  2943     algorithm) and must be replaced by the pattern
  2944 
  2945       have "EX S. P S"
  2946       proof
  2947         show "P S" <...>
  2948       qed
  2949 
  2950   - Calculational reasoning with subst (or similar rules):
  2951     The proof pattern
  2952 
  2953       have "P (S::'a set)" <...>
  2954       also have "S = T" <...>
  2955       finally have "P T" .
  2956 
  2957     no longer works (for similar reasons as the previous example) and
  2958     must be replaced by something like
  2959 
  2960       have "P (S::'a set)" <...>
  2961       moreover have "S = T" <...>
  2962       ultimately have "P T" by simp
  2963 
  2964   - Tactics or packages written in ML code:
  2965     Code performing pattern matching on types via
  2966 
  2967       Type ("set", [T]) => ...
  2968 
  2969     must be rewritten. Moreover, functions like strip_type or
  2970     binder_types no longer return the right value when applied to a
  2971     type of the form
  2972 
  2973       T1 => ... => Tn => U => bool
  2974 
  2975     rather than
  2976 
  2977       T1 => ... => Tn => U set
  2978 
  2979 * Merged theories Wellfounded_Recursion, Accessible_Part and
  2980 Wellfounded_Relations to theory Wellfounded.
  2981 
  2982 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  2983 
  2984 * Class finite no longer treats UNIV as class parameter.  Use class
  2985 enum from theory Library/Enum instead to achieve a similar effect.
  2986 INCOMPATIBILITY.
  2987 
  2988 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  2989 and "Cons".  INCOMPATIBILITY.
  2990 
  2991 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  2992 Potential INCOMPATIBILITY.
  2993 
  2994 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  2995 injective_fst_snd removed, use split_eta and prod_eqI instead.
  2996 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  2997 
  2998 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  2999 the same name in theory Orderings:
  3000 
  3001   less_trans
  3002   less_linear
  3003   le_imp_less_or_eq
  3004   le_less_trans
  3005   less_le_trans
  3006   less_not_sym
  3007   less_asym
  3008 
  3009 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  3010 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  3011 and different variable names.
  3012 
  3013 * Library/Option_ord.thy: Canonical order on option type.
  3014 
  3015 * Library/RBT.thy: Red-black trees, an efficient implementation of
  3016 finite maps.
  3017 
  3018 * Library/Countable.thy: Type class for countable types.
  3019 
  3020 * Theory Int: The representation of numerals has changed.  The infix
  3021 operator BIT and the bit datatype with constructors B0 and B1 have
  3022 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  3023 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  3024 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  3025 accordingly.
  3026 
  3027 * Theory Nat: definition of <= and < on natural numbers no longer
  3028 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  3029 le_def and less_def have disappeared.  Consider lemmas not_less
  3030 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  3031 
  3032 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  3033 (whose purpose mainly is for various fold_set functionals) have been
  3034 abandoned in favor of the existing algebraic classes
  3035 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  3036 lower_semilattice (resp. upper_semilattice) and linorder.
  3037 INCOMPATIBILITY.
  3038 
  3039 * Theory Transitive_Closure: induct and cases rules now declare proper
  3040 case_names ("base" and "step").  INCOMPATIBILITY.
  3041 
  3042 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  3043 lattices.  The form set-specific version is available as
  3044 Inductive.lfp_ordinal_induct_set.
  3045 
  3046 * Renamed theorems "power.simps" to "power_int.simps".
  3047 INCOMPATIBILITY.
  3048 
  3049 * Class semiring_div provides basic abstract properties of semirings
  3050 with division and modulo operations.  Subsumes former class dvd_mod.
  3051 
  3052 * Merged theories IntDef, Numeral and IntArith into unified theory
  3053 Int.  INCOMPATIBILITY.
  3054 
  3055 * Theory Library/Code_Index: type "index" now represents natural
  3056 numbers rather than integers.  INCOMPATIBILITY.
  3057 
  3058 * New class "uminus" with operation "uminus" (split of from class
  3059 "minus" which now only has operation "minus", binary).
  3060 INCOMPATIBILITY.
  3061 
  3062 * Constants "card", "internal_split", "option_map" now with authentic
  3063 syntax.  INCOMPATIBILITY.
  3064 
  3065 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3066 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3067 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3068 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3069 Sup_set_def, le_def, less_def, option_map_def now with object
  3070 equality.  INCOMPATIBILITY.
  3071 
  3072 * Records. Removed K_record, and replaced it by pure lambda term
  3073 %x. c. The simplifier setup is now more robust against eta expansion.
  3074 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3075 
  3076 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3077 
  3078 * Library/ListVector: new theory of arithmetic vector operations.
  3079 
  3080 * Library/Order_Relation: new theory of various orderings as sets of
  3081 pairs.  Defines preorders, partial orders, linear orders and
  3082 well-orders on sets and on types.
  3083 
  3084 
  3085 *** ZF ***
  3086 
  3087 * Renamed some theories to allow to loading both ZF and HOL in the
  3088 same session:
  3089 
  3090   Datatype  -> Datatype_ZF
  3091   Inductive -> Inductive_ZF
  3092   Int       -> Int_ZF
  3093   IntDiv    -> IntDiv_ZF
  3094   Nat       -> Nat_ZF
  3095   List      -> List_ZF
  3096   Main      -> Main_ZF
  3097 
  3098 INCOMPATIBILITY: ZF theories that import individual theories below
  3099 Main might need to be adapted.  Regular theory Main is still
  3100 available, as trivial extension of Main_ZF.
  3101 
  3102 
  3103 *** ML ***
  3104 
  3105 * ML within Isar: antiquotation @{const name} or @{const
  3106 name(typargs)} produces statically-checked Const term.
  3107 
  3108 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3109 (of the same name).  Removed obsolete print command.
  3110 
  3111 * Removed obsolete "use_legacy_bindings" function.
  3112 
  3113 * The ``print mode'' is now a thread-local value derived from a global
  3114 template (the former print_mode reference), thus access becomes
  3115 non-critical.  The global print_mode reference is for session
  3116 management only; user-code should use print_mode_value,
  3117 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3118 
  3119 * Functions system/system_out provide a robust way to invoke external
  3120 shell commands, with propagation of interrupts (requires Poly/ML
  3121 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3122 
  3123 
  3124 *** System ***
  3125 
  3126 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3127 in accordance with Proof General 3.7, which prefers GNU emacs.
  3128 
  3129 * isatool tty runs Isabelle process with plain tty interaction;
  3130 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3131 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3132 
  3133 * isatool browser now works with Cygwin as well, using general
  3134 "javapath" function defined in Isabelle process environment.
  3135 
  3136 * YXML notation provides a simple and efficient alternative to
  3137 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3138 isatool yxml as described in the Isabelle system manual.
  3139 
  3140 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3141 provides general wrapper for managing an Isabelle process in a robust
  3142 fashion, with ``cooked'' output from stdin/stderr.
  3143 
  3144 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3145 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3146 
  3147 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3148 way of changing the user's settings is via
  3149 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3150 script.
  3151 
  3152 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3153 cores of the underlying machine, which is a good starting point for
  3154 optimal performance tuning.  The corresponding usedir option -M allows
  3155 "max" as an alias for "0".  WARNING: does not work on certain versions
  3156 of Mac OS (with Poly/ML 5.1).
  3157 
  3158 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3159 adverse effect of Isabelle flooding interactive front-ends (notably
  3160 ProofGeneral / XEmacs).
  3161 
  3162 
  3163 
  3164 New in Isabelle2007 (November 2007)
  3165 -----------------------------------
  3166 
  3167 *** General ***
  3168 
  3169 * More uniform information about legacy features, notably a
  3170 warning/error of "Legacy feature: ...", depending on the state of the
  3171 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3172 legacy features will disappear eventually.
  3173 
  3174 * Theory syntax: the header format ``theory A = B + C:'' has been
  3175 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3176 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3177 
  3178 * Theory syntax: the old non-Isar theory file format has been
  3179 discontinued altogether.  Note that ML proof scripts may still be used
  3180 with Isar theories; migration is usually quite simple with the ML
  3181 function use_legacy_bindings.  INCOMPATIBILITY.
  3182 
  3183 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3184 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3185 quotes.
  3186 
  3187 * Theory loader: be more serious about observing the static theory
  3188 header specifications (including optional directories), but not the
  3189 accidental file locations of previously successful loads.  The strict
  3190 update policy of former update_thy is now already performed by
  3191 use_thy, so the former has been removed; use_thys updates several
  3192 theories simultaneously, just as 'imports' within a theory header
  3193 specification, but without merging the results.  Potential
  3194 INCOMPATIBILITY: may need to refine theory headers and commands
  3195 ROOT.ML which depend on load order.
  3196 
  3197 * Theory loader: optional support for content-based file
  3198 identification, instead of the traditional scheme of full physical
  3199 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3200 (cf. the system manual).  The new scheme allows to work with
  3201 non-finished theories in persistent session images, such that source
  3202 files may be moved later on without requiring reloads.
  3203 
  3204 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3205 file (with the same base name as the theory) are considered a legacy
  3206 feature, which will disappear eventually. Even now, the theory loader
  3207 no longer maintains dependencies on such files.
  3208 
  3209 * Syntax: the scope for resolving ambiguities via type-inference is
  3210 now limited to individual terms, instead of whole simultaneous
  3211 specifications as before. This greatly reduces the complexity of the
  3212 syntax module and improves flexibility by separating parsing and
  3213 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3214 'fixes' etc.) are required in rare situations.
  3215 
  3216 * Syntax: constants introduced by new-style packages ('definition',
  3217 'abbreviation' etc.) are passed through the syntax module in
  3218 ``authentic mode''. This means that associated mixfix annotations
  3219 really stick to such constants, independently of potential name space
  3220 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3221 trees are represented slightly differently, may need to adapt syntax
  3222 translations accordingly. Use CONST marker in 'translations' and
  3223 @{const_syntax} antiquotation in 'parse_translation' etc.
  3224 
  3225 * Legacy goal package: reduced interface to the bare minimum required
  3226 to keep existing proof scripts running.  Most other user-level
  3227 functions are now part of the OldGoals structure, which is *not* open
  3228 by default (consider isatool expandshort before open OldGoals).
  3229 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3230 these tend to cause confusion about the actual goal (!) context being
  3231 used here, which is not necessarily the same as the_context().
  3232 
  3233 * Command 'find_theorems': supports "*" wild-card in "name:"
  3234 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3235 support a specific search form (see ProofGeneral/CHANGES).
  3236 
  3237 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3238 by default, which means that "prems" (and also "fixed variables") are
  3239 suppressed from proof state output.  Note that the ProofGeneral
  3240 settings mechanism allows to change and save options persistently, but
  3241 older versions of Isabelle will fail to start up if a negative prems
  3242 limit is imposed.
  3243 
  3244 * Local theory targets may be specified by non-nested blocks of
  3245 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3246 contain definitions, theorems etc., including any derived mechanism
  3247 that has been implemented on top of these primitives.  This concept
  3248 generalizes the existing ``theorem (in ...)'' towards more versatility
  3249 and scalability.
  3250 
  3251 * Proof General interface: proper undo of final 'end' command;
  3252 discontinued Isabelle/classic mode (ML proof scripts).
  3253 
  3254 
  3255 *** Document preparation ***
  3256 
  3257 * Added antiquotation @{theory name} which prints the given name,
  3258 after checking that it refers to a valid ancestor theory in the
  3259 current context.
  3260 
  3261 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3262 check the given source text as ML type/structure, printing verbatim.
  3263 
  3264 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3265 "c args == rhs" given in the current context.  (Any number of
  3266 arguments may be given on the LHS.)
  3267 
  3268 
  3269 *** Pure ***
  3270 
  3271 * The 'class' package offers a combination of axclass and locale to
  3272 achieve Haskell-like type classes in Isabelle.  Definitions and
  3273 theorems within a class context produce both relative results (with
  3274 implicit parameters according to the locale context), and polymorphic
  3275 constants with qualified polymorphism (according to the class
  3276 context).  Within the body context of a 'class' target, a separate
  3277 syntax layer ("user space type system") takes care of converting
  3278 between global polymorphic consts and internal locale representation.
  3279 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3280 "isatool doc classes" provides a tutorial.
  3281 
  3282 * Generic code generator framework allows to generate executable
  3283 code for ML and Haskell (including Isabelle classes).  A short usage
  3284 sketch:
  3285 
  3286     internal compilation:
  3287         export_code <list of constants (term syntax)> in SML
  3288     writing SML code to a file:
  3289         export_code <list of constants (term syntax)> in SML <filename>
  3290     writing OCaml code to a file:
  3291         export_code <list of constants (term syntax)> in OCaml <filename>
  3292     writing Haskell code to a bunch of files:
  3293         export_code <list of constants (term syntax)> in Haskell <filename>
  3294 
  3295     evaluating closed propositions to True/False using code generation:
  3296         method ``eval''
  3297 
  3298 Reasonable default setup of framework in HOL.
  3299 
  3300 Theorem attributs for selecting and transforming function equations theorems:
  3301 
  3302     [code fun]:        select a theorem as function equation for a specific constant
  3303     [code fun del]:    deselect a theorem as function equation for a specific constant
  3304     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3305     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3306 
  3307 User-defined serializations (target in {SML, OCaml, Haskell}):
  3308 
  3309     code_const <and-list of constants (term syntax)>
  3310       {(target) <and-list of const target syntax>}+
  3311 
  3312     code_type <and-list of type constructors>
  3313       {(target) <and-list of type target syntax>}+
  3314 
  3315     code_instance <and-list of instances>
  3316       {(target)}+
  3317         where instance ::= <type constructor> :: <class>
  3318 
  3319     code_class <and_list of classes>
  3320       {(target) <and-list of class target syntax>}+
  3321         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3322 
  3323 code_instance and code_class only are effective to target Haskell.
  3324 
  3325 For example usage see src/HOL/ex/Codegenerator.thy and
  3326 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3327 generation from Isabelle/HOL theories is available via "isatool doc
  3328 codegen".
  3329 
  3330 * Code generator: consts in 'consts_code' Isar commands are now
  3331 referred to by usual term syntax (including optional type
  3332 annotations).
  3333 
  3334 * Command 'no_translations' removes translation rules from theory
  3335 syntax.
  3336 
  3337 * Overloaded definitions are now actually checked for acyclic
  3338 dependencies.  The overloading scheme is slightly more general than
  3339 that of Haskell98, although Isabelle does not demand an exact
  3340 correspondence to type class and instance declarations.
  3341 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3342 exotic versions of overloading -- at the discretion of the user!
  3343 
  3344 Polymorphic constants are represented via type arguments, i.e. the
  3345 instantiation that matches an instance against the most general
  3346 declaration given in the signature.  For example, with the declaration
  3347 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3348 as c(nat).  Overloading is essentially simultaneous structural
  3349 recursion over such type arguments.  Incomplete specification patterns
  3350 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3351 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3352 Command 'print_theory' outputs the normalized system of recursive
  3353 equations, see section "definitions".
  3354 
  3355 * Configuration options are maintained within the theory or proof
  3356 context (with name and type bool/int/string), providing a very simple
  3357 interface to a poor-man's version of general context data.  Tools may
  3358 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3359 these values using Config.get etc.  Users may change options via an
  3360 associated attribute of the same name.  This form of context
  3361 declaration works particularly well with commands 'declare' or
  3362 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3363 very easy to avoid global references, which would not observe Isar
  3364 toplevel undo/redo and fail to work with multithreading.
  3365 
  3366 Various global ML references of Pure and HOL have been turned into
  3367 configuration options:
  3368 
  3369   Unify.search_bound		unify_search_bound
  3370   Unify.trace_bound		unify_trace_bound
  3371   Unify.trace_simp		unify_trace_simp
  3372   Unify.trace_types		unify_trace_types
  3373   Simplifier.simp_depth_limit	simp_depth_limit
  3374   Blast.depth_limit		blast_depth_limit
  3375   DatatypeProp.dtK		datatype_distinctness_limit
  3376   fast_arith_neq_limit  	fast_arith_neq_limit
  3377   fast_arith_split_limit	fast_arith_split_limit
  3378 
  3379 * Named collections of theorems may be easily installed as context
  3380 data using the functor NamedThmsFun (see also
  3381 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3382 attributes; there is also a toplevel print command.  This facility is
  3383 just a common case of general context data, which is the preferred way
  3384 for anything more complex than just a list of facts in canonical
  3385 order.
  3386 
  3387 * Isar: command 'declaration' augments a local theory by generic
  3388 declaration functions written in ML.  This enables arbitrary content
  3389 being added to the context, depending on a morphism that tells the
  3390 difference of the original declaration context wrt. the application
  3391 context encountered later on.
  3392 
  3393 * Isar: proper interfaces for simplification procedures.  Command
  3394 'simproc_setup' declares named simprocs (with match patterns, and body
  3395 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3396 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3397 
  3398 * Isar: an extra pair of brackets around attribute declarations
  3399 abbreviates a theorem reference involving an internal dummy fact,
  3400 which will be ignored later --- only the effect of the attribute on
  3401 the background context will persist.  This form of in-place
  3402 declarations is particularly useful with commands like 'declare' and
  3403 'using', for example ``have A using [[simproc a]] by simp''.
  3404 
  3405 * Isar: method "assumption" (and implicit closing of subproofs) now
  3406 takes simple non-atomic goal assumptions into account: after applying
  3407 an assumption as a rule the resulting subgoals are solved by atomic
  3408 assumption steps.  This is particularly useful to finish 'obtain'
  3409 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3410 without referring to the original premise "!!x. P x ==> thesis" in the
  3411 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3412 more permissive.
  3413 
  3414 * Isar: implicit use of prems from the Isar proof context is
  3415 considered a legacy feature.  Common applications like ``have A .''
  3416 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3417 referencing facts explicitly here improves readability and
  3418 maintainability of proof texts.
  3419 
  3420 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3421 the obtained context from the course of reasoning!  For example:
  3422 
  3423   assume "EX x y. A x & B y"   -- "any previous fact"
  3424   then guess x and y by clarify
  3425 
  3426 This technique is potentially adventurous, depending on the facts and
  3427 proof tools being involved here.
  3428 
  3429 * Isar: known facts from the proof context may be specified as literal
  3430 propositions, using ASCII back-quote syntax.  This works wherever
  3431 named facts used to be allowed so far, in proof commands, proof
  3432 methods, attributes etc.  Literal facts are retrieved from the context
  3433 according to unification of type and term parameters.  For example,
  3434 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3435 theorems in the current context, then these are valid literal facts:
  3436 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3437 
  3438 There is also a proof method "fact" which does the same composition
  3439 for explicit goal states, e.g. the following proof texts coincide with
  3440 certain special cases of literal facts:
  3441 
  3442   have "A" by fact                 ==  note `A`
  3443   have "A ==> B" by fact           ==  note `A ==> B`
  3444   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3445   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3446 
  3447 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3448 outer syntax.  Thus symbolic identifiers may be used without
  3449 additional white space in declarations like this: ``assume *: A''.
  3450 
  3451 * Isar: 'print_facts' prints all local facts of the current context,
  3452 both named and unnamed ones.
  3453 
  3454 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3455 
  3456   def x == "t" and y == "u"
  3457 
  3458 * Isar: added command 'unfolding', which is structurally similar to
  3459 'using', but affects both the goal state and facts by unfolding given
  3460 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3461 'unfolded' attribute may be replaced by first-class proof text.
  3462 
  3463 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3464 and command 'unfolding' now all support object-level equalities
  3465 (potentially conditional).  The underlying notion of rewrite rule is
  3466 analogous to the 'rule_format' attribute, but *not* that of the
  3467 Simplifier (which is usually more generous).
  3468 
  3469 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3470 premises of a theorem by n. Useful in conjunction with drule.
  3471 
  3472 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3473 method expression within a sandbox consisting of the first N
  3474 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3475 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3476 simplifies all new goals that emerge from applying rule foo to the
  3477 originally first one.
  3478 
  3479 * Isar: schematic goals are no longer restricted to higher-order
  3480 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3481 expected.
  3482 
  3483 * Isar: the conclusion of a long theorem statement is now either
  3484 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3485 (essentially a disjunction of cases with local parameters and
  3486 assumptions).  The latter allows to express general elimination rules
  3487 adequately; in this notation common elimination rules look like this:
  3488 
  3489   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3490     assumes "EX x. P x"
  3491     obtains x where "P x"
  3492 
  3493   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3494     assumes "A & B"
  3495     obtains A and B
  3496 
  3497   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3498     assumes "A | B"
  3499     obtains
  3500       A
  3501     | B
  3502 
  3503 The subsequent classical rules even refer to the formal "thesis"
  3504 explicitly:
  3505 
  3506   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3507     obtains "~ thesis"
  3508 
  3509   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3510     obtains "thesis ==> something"
  3511 
  3512 The actual proof of an 'obtains' statement is analogous to that of the
  3513 Isar proof element 'obtain', only that there may be several cases.
  3514 Optional case names may be specified in parentheses; these will be
  3515 available both in the present proof and as annotations in the
  3516 resulting rule, for later use with the 'cases' method (cf. attribute
  3517 case_names).
  3518 
  3519 * Isar: the assumptions of a long theorem statement are available as
  3520 "assms" fact in the proof context.  This is more appropriate than the
  3521 (historical) "prems", which refers to all assumptions of the current
  3522 context, including those from the target locale, proof body etc.
  3523 
  3524 * Isar: 'print_statement' prints theorems from the current theory or
  3525 proof context in long statement form, according to the syntax of a
  3526 top-level lemma.
  3527 
  3528 * Isar: 'obtain' takes an optional case name for the local context
  3529 introduction rule (default "that").
  3530 
  3531 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3532 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3533 to occur.
  3534 
  3535 * Pure: syntax "CONST name" produces a fully internalized constant
  3536 according to the current context.  This is particularly useful for
  3537 syntax translations that should refer to internal constant
  3538 representations independently of name spaces.
  3539 
  3540 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3541 instead of "FOO ". This allows multiple binder declarations to coexist
  3542 in the same context.  INCOMPATIBILITY.
  3543 
  3544 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3545 primitive that also works in a locale context (both for constants and
  3546 fixed variables). Type declaration and internal syntactic representation
  3547 of given constants retrieved from the context. Likewise, the
  3548 'no_notation' command allows to remove given syntax annotations from the
  3549 current context.
  3550 
  3551 * Isar/locales: new derived specification elements 'axiomatization',
  3552 'definition', 'abbreviation', which support type-inference, admit
  3553 object-level specifications (equality, equivalence).  See also the
  3554 isar-ref manual.  Examples:
  3555 
  3556   axiomatization
  3557     eq  (infix "===" 50) where
  3558     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3559 
  3560   definition "f x y = x + y + 1"
  3561   definition g where "g x = f x x"
  3562 
  3563   abbreviation
  3564     neq  (infix "=!=" 50) where
  3565     "x =!= y == ~ (x === y)"
  3566 
  3567 These specifications may be also used in a locale context.  Then the
  3568 constants being introduced depend on certain fixed parameters, and the
  3569 constant name is qualified by the locale base name.  An internal
  3570 abbreviation takes care for convenient input and output, making the
  3571 parameters implicit and using the original short name.  See also
  3572 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3573 entities from a monomorphic theory.
  3574 
  3575 Presently, abbreviations are only available 'in' a target locale, but
  3576 not inherited by general import expressions.  Also note that
  3577 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3578 'translations' in common applications.  The "no_abbrevs" print mode
  3579 prevents folding of abbreviations in term output.
  3580 
  3581 Concrete syntax is attached to specified constants in internal form,
  3582 independently of name spaces.  The parse tree representation is
  3583 slightly different -- use 'notation' instead of raw 'syntax', and
  3584 'translations' with explicit "CONST" markup to accommodate this.
  3585 
  3586 * Pure/Isar: unified syntax for new-style specification mechanisms
  3587 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3588 full type inference and dummy patterns ("_").  For example:
  3589 
  3590   definition "K x _ = x"
  3591 
  3592   inductive conj for A B
  3593   where "A ==> B ==> conj A B"
  3594 
  3595 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3596 the current context.  Print mode "no_abbrevs" prevents inversion of
  3597 abbreviations on output.
  3598 
  3599 * Isar/locales: improved parameter handling: use of locales "var" and
  3600 "struct" no longer necessary; - parameter renamings are no longer
  3601 required to be injective.  For example, this allows to define
  3602 endomorphisms as locale endom = homom mult mult h.
  3603 
  3604 * Isar/locales: changed the way locales with predicates are defined.
  3605 Instead of accumulating the specification, the imported expression is
  3606 now an interpretation.  INCOMPATIBILITY: different normal form of
  3607 locale expressions.  In particular, in interpretations of locales with
  3608 predicates, goals repesenting already interpreted fragments are not
  3609 removed automatically.  Use methods `intro_locales' and
  3610 `unfold_locales'; see below.
  3611 
  3612 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3613 provide backward reasoning on locales predicates.  The methods are
  3614 aware of interpretations and discharge corresponding goals.
  3615 `intro_locales' is less aggressive then `unfold_locales' and does not
  3616 unfold predicates to assumptions.
  3617 
  3618 * Isar/locales: the order in which locale fragments are accumulated
  3619 has changed.  This enables to override declarations from fragments due
  3620 to interpretations -- for example, unwanted simp rules.
  3621 
  3622 * Isar/locales: interpretation in theories and proof contexts has been
  3623 extended.  One may now specify (and prove) equations, which are
  3624 unfolded in interpreted theorems.  This is useful for replacing
  3625 defined concepts (constants depending on locale parameters) by
  3626 concepts already existing in the target context.  Example:
  3627 
  3628   interpretation partial_order ["op <= :: [int, int] => bool"]
  3629     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3630 
  3631 Typically, the constant `partial_order.less' is created by a
  3632 definition specification element in the context of locale
  3633 partial_order.
  3634 
  3635 * Method "induct": improved internal context management to support
  3636 local fixes and defines on-the-fly. Thus explicit meta-level
  3637 connectives !!  and ==> are rarely required anymore in inductive goals
  3638 (using object-logic connectives for this purpose has been long
  3639 obsolete anyway). Common proof patterns are explained in
  3640 src/HOL/Induct/Common_Patterns.thy, see also
  3641 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3642 examples.
  3643 
  3644 * Method "induct": improved handling of simultaneous goals. Instead of
  3645 introducing object-level conjunction, the statement is now split into
  3646 several conclusions, while the corresponding symbolic cases are nested
  3647 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3648 see src/HOL/Induct/Common_Patterns.thy, for example.
  3649 
  3650 * Method "induct": mutual induction rules are now specified as a list
  3651 of rule sharing the same induction cases. HOL packages usually provide
  3652 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3653 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3654 mutual induction rules differently, i.e. like this:
  3655 
  3656   (induct rule: foo_bar.inducts)
  3657   (induct set: foo bar)
  3658   (induct pred: foo bar)
  3659   (induct type: foo bar)
  3660 
  3661 The ML function ProjectRule.projections turns old-style rules into the
  3662 new format.
  3663 
  3664 * Method "coinduct": dual of induction, see
  3665 src/HOL/Library/Coinductive_List.thy for various examples.
  3666 
  3667 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3668 considered a legacy feature.
  3669 
  3670 * Attribute "symmetric" produces result with standardized schematic
  3671 variables (index 0).  Potential INCOMPATIBILITY.
  3672 
  3673 * Simplifier: by default the simplifier trace only shows top level
  3674 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3675 default. Thus there is less danger of being flooded by the trace. The
  3676 trace indicates where parts have been suppressed.
  3677   
  3678 * Provers/classical: removed obsolete classical version of elim_format
  3679 attribute; classical elim/dest rules are now treated uniformly when
  3680 manipulating the claset.
  3681 
  3682 * Provers/classical: stricter checks to ensure that supplied intro,
  3683 dest and elim rules are well-formed; dest and elim rules must have at
  3684 least one premise.
  3685 
  3686 * Provers/classical: attributes dest/elim/intro take an optional
  3687 weight argument for the rule (just as the Pure versions).  Weights are
  3688 ignored by automated tools, but determine the search order of single
  3689 rule steps.
  3690 
  3691 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3692 where the body does not mention the bound variable.  Note that dummy
  3693 patterns implicitly depend on their context of bounds, which makes
  3694 "{_. _}" match any set comprehension as expected.  Potential
  3695 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3696 constant "_idtdummy" in the binding position.
  3697 
  3698 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3699 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3700 for example "A -> B" => "Pi A (%_. B)".
  3701 
  3702 * Pure: 'class_deps' command visualizes the subclass relation, using
  3703 the graph browser tool.
  3704 
  3705 * Pure: 'print_theory' now suppresses certain internal declarations by
  3706 default; use '!' option for full details.
  3707 
  3708 
  3709 *** HOL ***
  3710 
  3711 * Method "metis" proves goals by applying the Metis general-purpose
  3712 resolution prover (see also http://gilith.com/software/metis/).
  3713 Examples are in the directory MetisExamples.  WARNING: the
  3714 Isabelle/HOL-Metis integration does not yet work properly with
  3715 multi-threading.
  3716   
  3717 * Command 'sledgehammer' invokes external automatic theorem provers as
  3718 background processes.  It generates calls to the "metis" method if
  3719 successful. These can be pasted into the proof.  Users do not have to
  3720 wait for the automatic provers to return.  WARNING: does not really
  3721 work with multi-threading.
  3722 
  3723 * New "auto_quickcheck" feature tests outermost goal statements for
  3724 potential counter-examples.  Controlled by ML references
  3725 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3726 5000 milliseconds).  Fails silently if statements is outside of
  3727 executable fragment, or any other codgenerator problem occurs.
  3728 
  3729 * New constant "undefined" with axiom "undefined x = undefined".
  3730 
  3731 * Added class "HOL.eq", allowing for code generation with polymorphic
  3732 equality.
  3733 
  3734 * Some renaming of class constants due to canonical name prefixing in
  3735 the new 'class' package:
  3736 
  3737     HOL.abs ~> HOL.abs_class.abs
  3738     HOL.divide ~> HOL.divide_class.divide
  3739     0 ~> HOL.zero_class.zero
  3740     1 ~> HOL.one_class.one
  3741     op + ~> HOL.plus_class.plus
  3742     op - ~> HOL.minus_class.minus
  3743     uminus ~> HOL.minus_class.uminus
  3744     op * ~> HOL.times_class.times
  3745     op < ~> HOL.ord_class.less
  3746     op <= > HOL.ord_class.less_eq
  3747     Nat.power ~> Power.power_class.power
  3748     Nat.size ~> Nat.size_class.size
  3749     Numeral.number_of ~> Numeral.number_class.number_of
  3750     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3751     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3752     Orderings.min ~> Orderings.ord_class.min
  3753     Orderings.max ~> Orderings.ord_class.max
  3754     Divides.op div ~> Divides.div_class.div
  3755     Divides.op mod ~> Divides.div_class.mod
  3756     Divides.op dvd ~> Divides.div_class.dvd
  3757 
  3758 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3759 
  3760 a) User-defined constants using any of the names "plus", "minus",
  3761 "times", "less" or "less_eq". The standard syntax translations for
  3762 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3763 names.
  3764 
  3765 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3766 INCOMPATIBILITY: use more specific names.
  3767 
  3768 c) Permutative equations (e.g. "a + b = b + a")
  3769 Since the change of names also changes the order of terms, permutative
  3770 rewrite rules may get applied in a different order. Experience shows
  3771 that this is rarely the case (only two adaptions in the whole Isabelle
  3772 distribution).  INCOMPATIBILITY: rewrite proofs
  3773 
  3774 d) ML code directly refering to constant names
  3775 This in general only affects hand-written proof tactics, simprocs and
  3776 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3777 Consider using @{const_name} antiquotation.
  3778 
  3779 * New class "default" with associated constant "default".
  3780 
  3781 * Function "sgn" is now overloaded and available on int, real, complex
  3782 (and other numeric types), using class "sgn".  Two possible defs of
  3783 sgn are given as equational assumptions in the classes sgn_if and
  3784 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3785 INCOMPATIBILITY.
  3786 
  3787 * Locale "partial_order" now unified with class "order" (cf. theory
  3788 Orderings), added parameter "less".  INCOMPATIBILITY.
  3789 
  3790 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3791 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3792 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3793 
  3794 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3795 changed order of proof goals in instance proofs.
  3796 
  3797 * The transitivity reasoner for partial and linear orders is set up
  3798 for classes "order" and "linorder".  Instances of the reasoner are available
  3799 in all contexts importing or interpreting the corresponding locales.
  3800 Method "order" invokes the reasoner separately; the reasoner
  3801 is also integrated with the Simplifier as a solver.  Diagnostic
  3802 command 'print_orders' shows the available instances of the reasoner
  3803 in the current context.
  3804 
  3805 * Localized monotonicity predicate in theory "Orderings"; integrated
  3806 lemmas max_of_mono and min_of_mono with this predicate.
  3807 INCOMPATIBILITY.
  3808 
  3809 * Formulation of theorem "dense" changed slightly due to integration
  3810 with new class dense_linear_order.
  3811 
  3812 * Uniform lattice theory development in HOL.
  3813 
  3814     constants "meet" and "join" now named "inf" and "sup"
  3815     constant "Meet" now named "Inf"
  3816 
  3817     classes "meet_semilorder" and "join_semilorder" now named
  3818       "lower_semilattice" and "upper_semilattice"
  3819     class "lorder" now named "lattice"
  3820     class "comp_lat" now named "complete_lattice"
  3821 
  3822     Instantiation of lattice classes allows explicit definitions
  3823     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3824 
  3825   INCOMPATIBILITY.  Theorem renames:
  3826 
  3827     meet_left_le            ~> inf_le1
  3828     meet_right_le           ~> inf_le2
  3829     join_left_le            ~> sup_ge1
  3830     join_right_le           ~> sup_ge2
  3831     meet_join_le            ~> inf_sup_ord
  3832     le_meetI                ~> le_infI
  3833     join_leI                ~> le_supI
  3834     le_meet                 ~> le_inf_iff
  3835     le_join                 ~> ge_sup_conv
  3836     meet_idempotent         ~> inf_idem
  3837     join_idempotent         ~> sup_idem
  3838     meet_comm               ~> inf_commute
  3839     join_comm               ~> sup_commute
  3840     meet_leI1               ~> le_infI1
  3841     meet_leI2               ~> le_infI2
  3842     le_joinI1               ~> le_supI1
  3843     le_joinI2               ~> le_supI2
  3844     meet_assoc              ~> inf_assoc
  3845     join_assoc              ~> sup_assoc
  3846     meet_left_comm          ~> inf_left_commute
  3847     meet_left_idempotent    ~> inf_left_idem
  3848     join_left_comm          ~> sup_left_commute
  3849     join_left_idempotent    ~> sup_left_idem
  3850     meet_aci                ~> inf_aci
  3851     join_aci                ~> sup_aci
  3852     le_def_meet             ~> le_iff_inf
  3853     le_def_join             ~> le_iff_sup
  3854     join_absorp2            ~> sup_absorb2
  3855     join_absorp1            ~> sup_absorb1
  3856     meet_absorp1            ~> inf_absorb1
  3857     meet_absorp2            ~> inf_absorb2
  3858     meet_join_absorp        ~> inf_sup_absorb
  3859     join_meet_absorp        ~> sup_inf_absorb
  3860     distrib_join_le         ~> distrib_sup_le
  3861     distrib_meet_le         ~> distrib_inf_le
  3862 
  3863     add_meet_distrib_left   ~> add_inf_distrib_left
  3864     add_join_distrib_left   ~> add_sup_distrib_left
  3865     is_join_neg_meet        ~> is_join_neg_inf
  3866     is_meet_neg_join        ~> is_meet_neg_sup
  3867     add_meet_distrib_right  ~> add_inf_distrib_right
  3868     add_join_distrib_right  ~> add_sup_distrib_right
  3869     add_meet_join_distribs  ~> add_sup_inf_distribs
  3870     join_eq_neg_meet        ~> sup_eq_neg_inf
  3871     meet_eq_neg_join        ~> inf_eq_neg_sup
  3872     add_eq_meet_join        ~> add_eq_inf_sup
  3873     meet_0_imp_0            ~> inf_0_imp_0
  3874     join_0_imp_0            ~> sup_0_imp_0
  3875     meet_0_eq_0             ~> inf_0_eq_0
  3876     join_0_eq_0             ~> sup_0_eq_0
  3877     neg_meet_eq_join        ~> neg_inf_eq_sup
  3878     neg_join_eq_meet        ~> neg_sup_eq_inf
  3879     join_eq_if              ~> sup_eq_if
  3880 
  3881     mono_meet               ~> mono_inf
  3882     mono_join               ~> mono_sup
  3883     meet_bool_eq            ~> inf_bool_eq
  3884     join_bool_eq            ~> sup_bool_eq
  3885     meet_fun_eq             ~> inf_fun_eq
  3886     join_fun_eq             ~> sup_fun_eq
  3887     meet_set_eq             ~> inf_set_eq
  3888     join_set_eq             ~> sup_set_eq
  3889     meet1_iff               ~> inf1_iff
  3890     meet2_iff               ~> inf2_iff
  3891     meet1I                  ~> inf1I
  3892     meet2I                  ~> inf2I
  3893     meet1D1                 ~> inf1D1
  3894     meet2D1                 ~> inf2D1
  3895     meet1D2                 ~> inf1D2
  3896     meet2D2                 ~> inf2D2
  3897     meet1E                  ~> inf1E
  3898     meet2E                  ~> inf2E
  3899     join1_iff               ~> sup1_iff
  3900     join2_iff               ~> sup2_iff
  3901     join1I1                 ~> sup1I1
  3902     join2I1                 ~> sup2I1
  3903     join1I1                 ~> sup1I1
  3904     join2I2                 ~> sup1I2
  3905     join1CI                 ~> sup1CI
  3906     join2CI                 ~> sup2CI
  3907     join1E                  ~> sup1E
  3908     join2E                  ~> sup2E
  3909 
  3910     is_meet_Meet            ~> is_meet_Inf
  3911     Meet_bool_def           ~> Inf_bool_def
  3912     Meet_fun_def            ~> Inf_fun_def
  3913     Meet_greatest           ~> Inf_greatest
  3914     Meet_lower              ~> Inf_lower
  3915     Meet_set_def            ~> Inf_set_def
  3916 
  3917     Sup_def                 ~> Sup_Inf
  3918     Sup_bool_eq             ~> Sup_bool_def
  3919     Sup_fun_eq              ~> Sup_fun_def
  3920     Sup_set_eq              ~> Sup_set_def
  3921 
  3922     listsp_meetI            ~> listsp_infI
  3923     listsp_meet_eq          ~> listsp_inf_eq
  3924 
  3925     meet_min                ~> inf_min
  3926     join_max                ~> sup_max
  3927 
  3928 * Added syntactic class "size"; overloaded constant "size" now has
  3929 type "'a::size ==> bool"
  3930 
  3931 * Internal reorganisation of `size' of datatypes: size theorems
  3932 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3933 simplification rules by default!); theorems "prod.size" now named
  3934 "*.size".
  3935 
  3936 * Class "div" now inherits from class "times" rather than "type".
  3937 INCOMPATIBILITY.
  3938 
  3939 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  3940 Linorder etc.  have disappeared; operations defined in terms of
  3941 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  3942 
  3943 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  3944 
  3945 * HOL-Word: New extensive library and type for generic, fixed size
  3946 machine words, with arithemtic, bit-wise, shifting and rotating
  3947 operations, reflection into int, nat, and bool lists, automation for
  3948 linear arithmetic (by automatic reflection into nat or int), including
  3949 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  3950 arithmetic type classes, supporting automatic simplification of
  3951 numerals on all operations.
  3952 
  3953 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  3954 
  3955 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  3956 
  3957 * Code generator library theories:
  3958   - Code_Integer represents HOL integers by big integer literals in target
  3959     languages.
  3960   - Code_Char represents HOL characters by character literals in target
  3961     languages.
  3962   - Code_Char_chr like Code_Char, but also offers treatment of character
  3963     codes; includes Code_Integer.
  3964   - Executable_Set allows to generate code for finite sets using lists.
  3965   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  3966     denominator).
  3967   - Executable_Real implements a subset of real numbers, namly those
  3968     representable by rational numbers.
  3969   - Efficient_Nat implements natural numbers by integers, which in general will
  3970     result in higher efficency; pattern matching with 0/Suc is eliminated;
  3971     includes Code_Integer.
  3972   - Code_Index provides an additional datatype index which is mapped to
  3973     target-language built-in integers.
  3974   - Code_Message provides an additional datatype message_string which is isomorphic to
  3975     strings; messages are mapped to target-language strings.
  3976 
  3977 * New package for inductive predicates
  3978 
  3979   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  3980 
  3981     inductive
  3982       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3983       for z_1 :: U_1 and ... and z_n :: U_m
  3984     where
  3985       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3986     | ...
  3987 
  3988   with full support for type-inference, rather than
  3989 
  3990     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3991 
  3992     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3993     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3994 
  3995     inductive "s z_1 ... z_m"
  3996     intros
  3997       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3998       ...
  3999 
  4000   For backward compatibility, there is a wrapper allowing inductive
  4001   sets to be defined with the new package via
  4002 
  4003     inductive_set
  4004       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4005       for z_1 :: U_1 and ... and z_n :: U_m
  4006     where
  4007       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4008     | ...
  4009 
  4010   or
  4011 
  4012     inductive_set
  4013       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4014       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4015       for z_1 :: U_1 and ... and z_n :: U_m
  4016     where
  4017       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4018     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4019     | ...
  4020 
  4021   if the additional syntax "p ..." is required.
  4022 
  4023   Numerous examples can be found in the subdirectories src/HOL/Auth,
  4024   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  4025 
  4026   INCOMPATIBILITIES:
  4027 
  4028   - Since declaration and definition of inductive sets or predicates
  4029     is no longer separated, abbreviations involving the newly
  4030     introduced sets or predicates must be specified together with the
  4031     introduction rules after the 'where' keyword (see above), rather
  4032     than before the actual inductive definition.
  4033 
  4034   - The variables in induction and elimination rules are now
  4035     quantified in the order of their occurrence in the introduction
  4036     rules, rather than in alphabetical order. Since this may break
  4037     some proofs, these proofs either have to be repaired, e.g. by
  4038     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  4039     statements of the form
  4040 
  4041       case (rule_i a_i_1 ... a_i_{k_i})
  4042 
  4043     or the old order of quantification has to be restored by explicitly adding
  4044     meta-level quantifiers in the introduction rules, i.e.
  4045 
  4046       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  4047 
  4048   - The format of the elimination rules is now
  4049 
  4050       p z_1 ... z_m x_1 ... x_n ==>
  4051         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4052         ==> ... ==> P
  4053 
  4054     for predicates and
  4055 
  4056       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4057         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4058         ==> ... ==> P
  4059 
  4060     for sets rather than
  4061 
  4062       x : s z_1 ... z_m ==>
  4063         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4064         ==> ... ==> P
  4065 
  4066     This may require terms in goals to be expanded to n-tuples
  4067     (e.g. using case_tac or simplification with the split_paired_all
  4068     rule) before the above elimination rule is applicable.
  4069 
  4070   - The elimination or case analysis rules for (mutually) inductive
  4071     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4072     list of rules "p_1_..._p_k.elims" is no longer available.
  4073 
  4074 * New package "function"/"fun" for general recursive functions,
  4075 supporting mutual and nested recursion, definitions in local contexts,
  4076 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4077 for small examples, and the separate tutorial on the function
  4078 package. The old recdef "package" is still available as before, but
  4079 users are encouraged to use the new package.
  4080 
  4081 * Method "lexicographic_order" automatically synthesizes termination
  4082 relations as lexicographic combinations of size measures. 
  4083 
  4084 * Case-expressions allow arbitrary constructor-patterns (including
  4085 "_") and take their order into account, like in functional
  4086 programming.  Internally, this is translated into nested
  4087 case-expressions; missing cases are added and mapped to the predefined
  4088 constant "undefined". In complicated cases printing may no longer show
  4089 the original input but the internal form. Lambda-abstractions allow
  4090 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4091 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4092 variable.
  4093 
  4094 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4095 is an abbreviation for "of_nat :: nat => int". The simplification
  4096 rules for "of_nat" have been changed to work like "int" did
  4097 previously.  Potential INCOMPATIBILITY:
  4098   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4099   - of_nat_diff and of_nat_mult are no longer default simp rules
  4100 
  4101 * Method "algebra" solves polynomial equations over (semi)rings using
  4102 Groebner bases. The (semi)ring structure is defined by locales and the
  4103 tool setup depends on that generic context. Installing the method for
  4104 a specific type involves instantiating the locale and possibly adding
  4105 declarations for computation on the coefficients.  The method is
  4106 already instantiated for natural numbers and for the axiomatic class
  4107 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4108 CALCULEMUS 2007 for the general principles underlying this
  4109 architecture of context-aware proof-tools.
  4110 
  4111 * Method "ferrack" implements quantifier elimination over
  4112 special-purpose dense linear orders using locales (analogous to
  4113 "algebra"). The method is already installed for class
  4114 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4115 rat, etc.
  4116 
  4117 * Former constant "List.op @" now named "List.append".  Use ML
  4118 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4119 circumvent possible incompatibilities when working on ML level.
  4120 
  4121 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4122 
  4123 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4124 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4125 
  4126 * New syntax for Haskell-like list comprehension (input only), eg.
  4127 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4128 
  4129 * The special syntax for function "filter" has changed from [x :
  4130 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4131 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4132 
  4133 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4134 defined on nat only, as an abbreviation for [a..<Suc b]
  4135 INCOMPATIBILITY.
  4136 
  4137 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4138 
  4139 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4140 
  4141 * New lemma collection field_simps (an extension of ring_simps) for
  4142 manipulating (in)equations involving division. Multiplies with all
  4143 denominators that can be proved to be non-zero (in equations) or
  4144 positive/negative (in inequations).
  4145 
  4146 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4147 have been improved and renamed to ring_simps, group_simps and
  4148 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4149 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4150 
  4151 * Theory Library/Commutative_Ring: switched from recdef to function
  4152 package; constants add, mul, pow now curried.  Infix syntax for
  4153 algebraic operations.
  4154 
  4155 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4156 INCOMPATIBILITY.
  4157 
  4158 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4159 INCOMPATIBILITY.
  4160 
  4161 * HOL/records: generalised field-update to take a function on the
  4162 field rather than the new value: r(|A := x|) is translated to A_update
  4163 (K x) r The K-combinator that is internally used is called K_record.
  4164 INCOMPATIBILITY: Usage of the plain update functions has to be
  4165 adapted.
  4166  
  4167 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4168 * x = 0, which are required for a semiring.  Richer structures do not
  4169 inherit from semiring_0 anymore, because this property is a theorem
  4170 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4171 there is more to prove, but this is mostly trivial.
  4172 
  4173 * Class "recpower" is generalized to arbitrary monoids, not just
  4174 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4175 commutativity or semiring properties additionally.
  4176 
  4177 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4178 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4179 better use 'abbreviation'.
  4180 
  4181 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4182 
  4183 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4184 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4185 significant changes for setting up numeral syntax for types:
  4186   - New constants Numeral.pred and Numeral.succ instead
  4187       of former Numeral.bin_pred and Numeral.bin_succ.
  4188   - Use integer operations instead of bin_add, bin_mult and so on.
  4189   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4190   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4191 
  4192 See src/HOL/Integ/IntArith.thy for an example setup.
  4193 
  4194 * Command 'normal_form' computes the normal form of a term that may
  4195 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4196 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4197 heavy-duty computations because the functions are compiled to ML
  4198 first.  Correspondingly, a method "normalization" is provided.  See
  4199 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4200 
  4201 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4202 25 like -->); output depends on the "iff" print_mode, the default is
  4203 "A = B" (with priority 50).
  4204 
  4205 * Relations less (<) and less_eq (<=) are also available on type bool.
  4206 Modified syntax to disallow nesting without explicit parentheses,
  4207 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4208 INCOMPATIBILITY.
  4209 
  4210 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4211 
  4212 * Relation composition operator "op O" now has precedence 75 and binds
  4213 stronger than union and intersection. INCOMPATIBILITY.
  4214 
  4215 * The old set interval syntax "{m..n(}" (and relatives) has been
  4216 removed.  Use "{m..<n}" (and relatives) instead.
  4217 
  4218 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4219 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4220 ``declare [[simproc del: neq]]''.
  4221 
  4222 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4223 True/False.
  4224 
  4225 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4226 
  4227 * Theorem setsum_mult renamed to setsum_right_distrib.
  4228 
  4229 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4230 ``rule'' method.
  4231 
  4232 * Reimplemented methods "sat" and "satx", with several improvements:
  4233 goals no longer need to be stated as "<prems> ==> False", equivalences
  4234 (i.e. "=" on type bool) are handled, variable names of the form
  4235 "lit_<n>" are no longer reserved, significant speedup.
  4236 
  4237 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4238 zChaff is still supported as well.
  4239 
  4240 * 'inductive' and 'datatype': provide projections of mutual rules,
  4241 bundled as foo_bar.inducts;
  4242 
  4243 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4244 Library.
  4245 
  4246 * Library: moved theory Accessible_Part to main HOL.
  4247 
  4248 * Library: added theory Coinductive_List of potentially infinite lists
  4249 as greatest fixed-point.
  4250 
  4251 * Library: added theory AssocList which implements (finite) maps as
  4252 association lists.
  4253 
  4254 * Method "evaluation" solves goals (i.e. a boolean expression)
  4255 efficiently by compiling it to ML.  The goal is "proved" (via an
  4256 oracle) if it evaluates to True.
  4257 
  4258 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4259 also when invoked by the simplifier.  This results in the Simplifier
  4260 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4261 Configuration option fast_arith_split_limit=0 recovers the old
  4262 behavior.
  4263 
  4264 * Support for hex (0x20) and binary (0b1001) numerals.
  4265 
  4266 * New method: reify eqs (t), where eqs are equations for an
  4267 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4268 parameter, computes a term s::'b and a list xs::'a list and proves the
  4269 theorem I xs s = t. This is also known as reification or quoting. The
  4270 resulting theorem is applied to the subgoal to substitute t with I xs
  4271 s.  If t is omitted, the subgoal itself is reified.
  4272 
  4273 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4274 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4275 where f is supposed to be a computable function (in the sense of code
  4276 generattion). The method uses reify to compute s and xs as above then
  4277 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4278 r and finally gets the theorem t = r, which is again applied to the
  4279 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4280 
  4281 * Reflection: Automatic reification now handels binding, an example is
  4282 available in src/HOL/ex/ReflectionEx.thy
  4283 
  4284 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4285 command 'statespace' that is similar to 'record', but introduces an
  4286 abstract specification based on the locale infrastructure instead of
  4287 HOL types.  This leads to extra flexibility in composing state spaces,
  4288 in particular multiple inheritance and renaming of components.
  4289 
  4290 
  4291 *** HOL-Complex ***
  4292 
  4293 * Hyperreal: Functions root and sqrt are now defined on negative real
  4294 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4295 Nonnegativity side conditions have been removed from many lemmas, so
  4296 that more subgoals may now be solved by simplification; potential
  4297 INCOMPATIBILITY.
  4298 
  4299 * Real: new type classes formalize real normed vector spaces and
  4300 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4301 and norm :: 'a => real.
  4302 
  4303 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4304 reals into other types. The overloaded constant Reals :: 'a set is now
  4305 defined as range of_real; potential INCOMPATIBILITY.
  4306 
  4307 * Real: proper support for ML code generation, including 'quickcheck'.
  4308 Reals are implemented as arbitrary precision rationals.
  4309 
  4310 * Hyperreal: Several constants that previously worked only for the
  4311 reals have been generalized, so they now work over arbitrary vector
  4312 spaces. Type annotations may need to be added in some cases; potential
  4313 INCOMPATIBILITY.
  4314 
  4315   Infinitesimal  :: ('a::real_normed_vector) star set
  4316   HFinite        :: ('a::real_normed_vector) star set
  4317   HInfinite      :: ('a::real_normed_vector) star set
  4318   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4319   monad          :: ('a::real_normed_vector) star => 'a star set
  4320   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4321   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4322   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4323   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4324   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4325   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4326   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4327   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4328   sgn            :: 'a::real_normed_vector => 'a
  4329   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4330 
  4331 * Complex: Some complex-specific constants are now abbreviations for
  4332 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4333 hnorm.  Other constants have been entirely removed in favor of the
  4334 polymorphic versions (INCOMPATIBILITY):
  4335 
  4336   approx        <-- capprox
  4337   HFinite       <-- CFinite
  4338   HInfinite     <-- CInfinite
  4339   Infinitesimal <-- CInfinitesimal
  4340   monad         <-- cmonad
  4341   galaxy        <-- cgalaxy
  4342   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4343   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4344   (ns)deriv     <-- (ns)cderiv
  4345 
  4346 
  4347 *** HOL-Algebra ***
  4348 
  4349 * Formalisation of ideals and the quotient construction over rings.
  4350 
  4351 * Order and lattice theory no longer based on records.
  4352 INCOMPATIBILITY.
  4353 
  4354 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4355 greatest_closed.  INCOMPATIBILITY.
  4356 
  4357 * Method algebra is now set up via an attribute.  For examples see
  4358 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4359 of algebraic structures.
  4360 
  4361 * Renamed theory CRing to Ring.
  4362 
  4363 
  4364 *** HOL-Nominal ***
  4365 
  4366 * Substantial, yet incomplete support for nominal datatypes (binding
  4367 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4368 src/HOL/Nominal/Examples.  Prospective users should consult
  4369 http://isabelle.in.tum.de/nominal/
  4370 
  4371 
  4372 *** ML ***
  4373 
  4374 * ML basics: just one true type int, which coincides with IntInf.int
  4375 (even on SML/NJ).
  4376 
  4377 * ML within Isar: antiquotations allow to embed statically-checked
  4378 formal entities in the source, referring to the context available at
  4379 compile-time.  For example:
  4380 
  4381 ML {* @{sort "{zero,one}"} *}
  4382 ML {* @{typ "'a => 'b"} *}
  4383 ML {* @{term "%x. x"} *}
  4384 ML {* @{prop "x == y"} *}
  4385 ML {* @{ctyp "'a => 'b"} *}
  4386 ML {* @{cterm "%x. x"} *}
  4387 ML {* @{cprop "x == y"} *}
  4388 ML {* @{thm asm_rl} *}
  4389 ML {* @{thms asm_rl} *}
  4390 ML {* @{type_name c} *}
  4391 ML {* @{type_syntax c} *}
  4392 ML {* @{const_name c} *}
  4393 ML {* @{const_syntax c} *}
  4394 ML {* @{context} *}
  4395 ML {* @{theory} *}
  4396 ML {* @{theory Pure} *}
  4397 ML {* @{theory_ref} *}
  4398 ML {* @{theory_ref Pure} *}
  4399 ML {* @{simpset} *}
  4400 ML {* @{claset} *}
  4401 ML {* @{clasimpset} *}
  4402 
  4403 The same works for sources being ``used'' within an Isar context.
  4404 
  4405 * ML in Isar: improved error reporting; extra verbosity with
  4406 ML_Context.trace enabled.
  4407 
  4408 * Pure/General/table.ML: the join operations now works via exceptions
  4409 DUP/SAME instead of type option. This is simpler in simple cases, and
  4410 admits slightly more efficient complex applications.
  4411 
  4412 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4413 use Context.generic instead of just theory.
  4414 
  4415 * Pure: datatype Context.generic joins theory/Proof.context and
  4416 provides some facilities for code that works in either kind of
  4417 context, notably GenericDataFun for uniform theory and proof data.
  4418 
  4419 * Pure: simplified internal attribute type, which is now always
  4420 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4421 local (Proof.context) attributes have been discontinued, while
  4422 minimizing code duplication. Thm.rule_attribute and
  4423 Thm.declaration_attribute build canonical attributes; see also structure
  4424 Context for further operations on Context.generic, notably
  4425 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4426 declarations and definitions.
  4427 
  4428 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4429 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4430 init only required for impure data. INCOMPATIBILITY: empty really need
  4431 to be empty (no dependencies on theory content!)
  4432 
  4433 * Pure/kernel: consts certification ignores sort constraints given in
  4434 signature declarations. (This information is not relevant to the
  4435 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4436 potential INCOMPATIBILITY.
  4437 
  4438 * Pure: axiomatic type classes are now purely definitional, with
  4439 explicit proofs of class axioms and super class relations performed
  4440 internally. See Pure/axclass.ML for the main internal interfaces --
  4441 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4442 AxClass.axiomatize_class/classrel/arity supersede
  4443 Sign.add_classes/classrel/arities.
  4444 
  4445 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4446 global/local versions on theory vs. Proof.context have been
  4447 discontinued; Attrib.syntax and Method.syntax have been adapted
  4448 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4449 attributes, methods, etc.
  4450 
  4451 * Pure: several functions of signature "... -> theory -> theory * ..."
  4452 have been reoriented to "... -> theory -> ... * theory" in order to
  4453 allow natural usage in combination with the ||>, ||>>, |-> and
  4454 fold_map combinators.
  4455 
  4456 * Pure: official theorem names (closed derivations) and additional
  4457 comments (tags) are now strictly separate.  Name hints -- which are
  4458 maintained as tags -- may be attached any time without affecting the
  4459 derivation.
  4460 
  4461 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4462 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4463 achieve the old behaviour.
  4464 
  4465 * Pure: the "Goal" constant is now called "prop", supporting a
  4466 slightly more general idea of ``protecting'' meta-level rule
  4467 statements.
  4468 
  4469 * Pure: Logic.(un)varify only works in a global context, which is now
  4470 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4471 Logic.legacy_(un)varify as temporary workaround.
  4472 
  4473 * Pure: structure Name provides scalable operations for generating
  4474 internal variable names, notably Name.variants etc.  This replaces
  4475 some popular functions from term.ML:
  4476 
  4477   Term.variant		->  Name.variant
  4478   Term.variantlist	->  Name.variant_list
  4479   Term.invent_names	->  Name.invent_list
  4480 
  4481 Note that low-level renaming rarely occurs in new code -- operations
  4482 from structure Variable are used instead (see below).
  4483 
  4484 * Pure: structure Variable provides fundamental operations for proper
  4485 treatment of fixed/schematic variables in a context.  For example,
  4486 Variable.import introduces fixes for schematics of given facts and
  4487 Variable.export reverses the effect (up to renaming) -- this replaces
  4488 various freeze_thaw operations.
  4489 
  4490 * Pure: structure Goal provides simple interfaces for
  4491 init/conclude/finish and tactical prove operations (replacing former
  4492 Tactic.prove).  Goal.prove is the canonical way to prove results
  4493 within a given context; Goal.prove_global is a degraded version for
  4494 theory level goals, including a global Drule.standard.  Note that
  4495 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4496 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4497 in a locale context).
  4498 
  4499 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4500 and type checking (Syntax.check_term etc.), with common combinations
  4501 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4502 which are considered legacy and await removal.
  4503 
  4504 * Pure/Syntax: generic interfaces for type unchecking
  4505 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4506 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4507 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4508 available for convenience, but refer to the very same operations using
  4509 a mere theory instead of a full context.
  4510 
  4511 * Isar: simplified treatment of user-level errors, using exception
  4512 ERROR of string uniformly.  Function error now merely raises ERROR,
  4513 without any side effect on output channels.  The Isar toplevel takes
  4514 care of proper display of ERROR exceptions.  ML code may use plain
  4515 handle/can/try; cat_error may be used to concatenate errors like this:
  4516 
  4517   ... handle ERROR msg => cat_error msg "..."
  4518 
  4519 Toplevel ML code (run directly or through the Isar toplevel) may be
  4520 embedded into the Isar toplevel with exception display/debug like
  4521 this:
  4522 
  4523   Isar.toplevel (fn () => ...)
  4524 
  4525 INCOMPATIBILITY, removed special transform_error facilities, removed
  4526 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4527 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4528 -- use plain ERROR instead.
  4529 
  4530 * Isar: theory setup now has type (theory -> theory), instead of a
  4531 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4532 
  4533 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4534 ProofContext.debug/verbose flags.
  4535 
  4536 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4537 theory before entering a proof state.  Transactions now always see a
  4538 quasi-functional intermediate checkpoint, both in interactive and
  4539 batch mode.
  4540 
  4541 * Isar: simplified interfaces for outer syntax.  Renamed
  4542 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4543 OuterSyntax.add_parsers -- this functionality is now included in
  4544 OuterSyntax.command etc.  INCOMPATIBILITY.
  4545 
  4546 * Simplifier: the simpset of a running simplification process now
  4547 contains a proof context (cf. Simplifier.the_context), which is the
  4548 very context that the initial simpset has been retrieved from (by
  4549 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4550 (solver, looper etc.) may depend on arbitrary proof data.
  4551 
  4552 * Simplifier.inherit_context inherits the proof context (plus the
  4553 local bounds) of the current simplification process; any simproc
  4554 etc. that calls the Simplifier recursively should do this!  Removed
  4555 former Simplifier.inherit_bounds, which is already included here --
  4556 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4557 specify an explicit context using Simplifier.context/theory_context.
  4558 
  4559 * Simplifier/Classical Reasoner: more abstract interfaces
  4560 change_simpset/claset for modifying the simpset/claset reference of a
  4561 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4562 INCOMPATIBILITY.
  4563 
  4564 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4565 "Trueprop" etc.
  4566 
  4567 
  4568 *** System ***
  4569 
  4570 * settings: the default heap location within ISABELLE_HOME_USER now
  4571 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4572 Isabelle installations.
  4573 
  4574 * isabelle-process: option -S (secure mode) disables some critical
  4575 operations, notably runtime compilation and evaluation of ML source
  4576 code.
  4577 
  4578 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4579 
  4580 * Support for parallel execution, using native multicore support of
  4581 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4582 independent theories, according to the given theory header
  4583 specifications. The maximum number of worker threads is specified via
  4584 usedir option -M or the "max-threads" setting in Proof General. A
  4585 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4586 to 6 on a 8-core machine.  User-code needs to observe certain
  4587 guidelines for thread-safe programming, see appendix A in the Isar
  4588 Implementation manual.
  4589 
  4590 
  4591 
  4592 New in Isabelle2005 (October 2005)
  4593 ----------------------------------
  4594 
  4595 *** General ***
  4596 
  4597 * Theory headers: the new header syntax for Isar theories is
  4598 
  4599   theory <name>
  4600   imports <theory1> ... <theoryN>
  4601   uses <file1> ... <fileM>
  4602   begin
  4603 
  4604 where the 'uses' part is optional.  The previous syntax
  4605 
  4606   theory <name> = <theory1> + ... + <theoryN>:
  4607 
  4608 will disappear in the next release.  Use isatool fixheaders to convert
  4609 existing theory files.  Note that there is no change in ancient
  4610 non-Isar theories now, but these will disappear soon.
  4611 
  4612 * Theory loader: parent theories can now also be referred to via
  4613 relative and absolute paths.
  4614 
  4615 * Command 'find_theorems' searches for a list of criteria instead of a
  4616 list of constants. Known criteria are: intro, elim, dest, name:string,
  4617 simp:term, and any term. Criteria can be preceded by '-' to select
  4618 theorems that do not match. Intro, elim, dest select theorems that
  4619 match the current goal, name:s selects theorems whose fully qualified
  4620 name contain s, and simp:term selects all simplification rules whose
  4621 lhs match term.  Any other term is interpreted as pattern and selects
  4622 all theorems matching the pattern. Available in ProofGeneral under
  4623 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4624 
  4625   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4626 
  4627 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4628 matching the current goal as introduction rule and not having "HOL."
  4629 in their name (i.e. not being defined in theory HOL).
  4630 
  4631 * Command 'thms_containing' has been discontinued in favour of
  4632 'find_theorems'; INCOMPATIBILITY.
  4633 
  4634 * Communication with Proof General is now 8bit clean, which means that
  4635 Unicode text in UTF-8 encoding may be used within theory texts (both
  4636 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4637 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4638 
  4639   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4640   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4641 
  4642 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4643 Classical Reasoner.  Typical big applications run around 2 times
  4644 faster.
  4645 
  4646 
  4647 *** Document preparation ***
  4648 
  4649 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4650 of raw sources.  Only those symbols that do not require additional
  4651 LaTeX packages (depending on comments in isabellesym.sty) are
  4652 displayed properly, everything else is left verbatim.  isatool display
  4653 and isatool print are used as front ends (these are subject to the
  4654 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4655 
  4656 * Command tags control specific markup of certain regions of text,
  4657 notably folding and hiding.  Predefined tags include "theory" (for
  4658 theory begin and end), "proof" for proof commands, and "ML" for
  4659 commands involving ML code; the additional tags "visible" and
  4660 "invisible" are unused by default.  Users may give explicit tag
  4661 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4662 interpretation of tags is determined by the LaTeX job during document
  4663 preparation: see option -V of isatool usedir, or options -n and -t of
  4664 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4665 \isadroptag.
  4666 
  4667 Several document versions may be produced at the same time via isatool
  4668 usedir (the generated index.html will link all of them).  Typical
  4669 specifications include ''-V document=theory,proof,ML'' to present
  4670 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4671 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4672 these parts without any formal replacement text.  The Isabelle site
  4673 default settings produce ''document'' and ''outline'' versions as
  4674 specified above.
  4675 
  4676 * Several new antiquotations:
  4677 
  4678   @{term_type term} prints a term with its type annotated;
  4679 
  4680   @{typeof term} prints the type of a term;
  4681 
  4682   @{const const} is the same as @{term const}, but checks that the
  4683   argument is a known logical constant;
  4684 
  4685   @{term_style style term} and @{thm_style style thm} print a term or
  4686   theorem applying a "style" to it
  4687 
  4688   @{ML text}
  4689 
  4690 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4691 definitions, equations, inequations etc., 'concl' printing only the
  4692 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4693 to print the specified premise.  TermStyle.add_style provides an ML
  4694 interface for introducing further styles.  See also the "LaTeX Sugar"
  4695 document practical applications.  The ML antiquotation prints
  4696 type-checked ML expressions verbatim.
  4697 
  4698 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4699 and 'text' support optional locale specification '(in loc)', which
  4700 specifies the default context for interpreting antiquotations.  For
  4701 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4702 
  4703 * Option 'locale=NAME' of antiquotations specifies an alternative
  4704 context interpreting the subsequent argument.  For example: @{thm
  4705 [locale=lattice] inf_assoc}.
  4706 
  4707 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4708 a proof context.
  4709 
  4710 * Proper output of antiquotations for theory commands involving a
  4711 proof context (such as 'locale' or 'theorem (in loc) ...').
  4712 
  4713 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4714 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4715 
  4716 * isatool usedir: new option -C (default true) controls whether option
  4717 -D should include a copy of the original document directory; -C false
  4718 prevents unwanted effects such as copying of administrative CVS data.
  4719 
  4720 
  4721 *** Pure ***
  4722 
  4723 * Considerably improved version of 'constdefs' command.  Now performs
  4724 automatic type-inference of declared constants; additional support for
  4725 local structure declarations (cf. locales and HOL records), see also
  4726 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4727 sequential dependencies of definitions within a single 'constdefs'
  4728 section; moreover, the declared name needs to be an identifier.  If
  4729 all fails, consider to fall back on 'consts' and 'defs' separately.
  4730 
  4731 * Improved indexed syntax and implicit structures.  First of all,
  4732 indexed syntax provides a notational device for subscripted
  4733 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4734 expressions.  Secondly, in a local context with structure
  4735 declarations, number indexes \<^sub>n or the empty index (default
  4736 number 1) refer to a certain fixed variable implicitly; option
  4737 show_structs controls printing of implicit structures.  Typical
  4738 applications of these concepts involve record types and locales.
  4739 
  4740 * New command 'no_syntax' removes grammar declarations (and
  4741 translations) resulting from the given syntax specification, which is
  4742 interpreted in the same manner as for the 'syntax' command.
  4743 
  4744 * 'Advanced' translation functions (parse_translation etc.) may depend
  4745 on the signature of the theory context being presently used for
  4746 parsing/printing, see also isar-ref manual.
  4747 
  4748 * Improved 'oracle' command provides a type-safe interface to turn an
  4749 ML expression of type theory -> T -> term into a primitive rule of
  4750 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4751 is already included here); see also FOL/ex/IffExample.thy;
  4752 INCOMPATIBILITY.
  4753 
  4754 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4755 before); "cI" is no longer bound, use "c.intro" instead.
  4756 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4757 axclasses vs. locales.
  4758 
  4759 * Improved internal renaming of symbolic identifiers -- attach primes
  4760 instead of base 26 numbers.
  4761 
  4762 * New flag show_question_marks controls printing of leading question
  4763 marks in schematic variable names.
  4764 
  4765 * In schematic variable names, *any* symbol following \<^isub> or
  4766 \<^isup> is now treated as part of the base name.  For example, the
  4767 following works without printing of awkward ".0" indexes:
  4768 
  4769   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4770     by simp
  4771 
  4772 * Inner syntax includes (*(*nested*) comments*).
  4773 
  4774 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4775 annotations as "(00...)".
  4776 
  4777 * Clear separation of logical types and nonterminals, where the latter
  4778 may only occur in 'syntax' specifications or type abbreviations.
  4779 Before that distinction was only partially implemented via type class
  4780 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4781 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4782 exotic syntax specifications may require further adaption
  4783 (e.g. Cube/Cube.thy).
  4784 
  4785 * Removed obsolete type class "logic", use the top sort {} instead.
  4786 Note that non-logical types should be declared as 'nonterminals'
  4787 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4788 specifications.
  4789 
  4790 * Attributes 'induct' and 'cases': type or set names may now be
  4791 locally fixed variables as well.
  4792 
  4793 * Simplifier: can now control the depth to which conditional rewriting
  4794 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4795 Limit.
  4796 
  4797 * Simplifier: simplification procedures may now take the current
  4798 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4799 interface), which is very useful for calling the Simplifier
  4800 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4801 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4802 low-level mk_simproc no longer applies Logic.varify internally, to
  4803 allow for use in a context of fixed variables.
  4804 
  4805 * thin_tac now works even if the assumption being deleted contains !!
  4806 or ==>.  More generally, erule now works even if the major premise of
  4807 the elimination rule contains !! or ==>.
  4808 
  4809 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4810 
  4811 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4812 from Pure, which contains all common declarations already.  Both
  4813 theories are defined via plain Isabelle/Isar .thy files.
  4814 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4815 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4816 use isatool fixcpure to adapt your theory and ML sources.
  4817 
  4818 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4819 selections of theorems in named facts via index ranges.
  4820 
  4821 * 'print_theorems': in theory mode, really print the difference
  4822 wrt. the last state (works for interactive theory development only),
  4823 in proof mode print all local facts (cf. 'print_facts');
  4824 
  4825 * 'hide': option '(open)' hides only base names.
  4826 
  4827 * More efficient treatment of intermediate checkpoints in interactive
  4828 theory development.
  4829 
  4830 * Code generator is now invoked via code_module (incremental code
  4831 generation) and code_library (modular code generation, ML structures
  4832 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4833 must be quoted when used as identifiers.
  4834 
  4835 * New 'value' command for reading, evaluating and printing terms using
  4836 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4837 quoted when used as identifier.
  4838 
  4839 
  4840 *** Locales ***
  4841 
  4842 * New commands for the interpretation of locale expressions in
  4843 theories (1), locales (2) and proof contexts (3).  These generate
  4844 proof obligations from the expression specification.  After the
  4845 obligations have been discharged, theorems of the expression are added
  4846 to the theory, target locale or proof context.  The synopsis of the
  4847 commands is a follows:
  4848 
  4849   (1) interpretation expr inst
  4850   (2) interpretation target < expr
  4851   (3) interpret expr inst
  4852 
  4853 Interpretation in theories and proof contexts require a parameter
  4854 instantiation of terms from the current context.  This is applied to
  4855 specifications and theorems of the interpreted expression.
  4856 Interpretation in locales only permits parameter renaming through the
  4857 locale expression.  Interpretation is smart in that interpretations
  4858 that are active already do not occur in proof obligations, neither are
  4859 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4860 inspect active interpretations of a particular locale.  For details,
  4861 see the Isar Reference manual.  Examples can be found in
  4862 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4863 
  4864 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4865 'interpret' instead.
  4866 
  4867 * New context element 'constrains' for adding type constraints to
  4868 parameters.
  4869 
  4870 * Context expressions: renaming of parameters with syntax
  4871 redeclaration.
  4872 
  4873 * Locale declaration: 'includes' disallowed.
  4874 
  4875 * Proper static binding of attribute syntax -- i.e. types / terms /
  4876 facts mentioned as arguments are always those of the locale definition
  4877 context, independently of the context of later invocations.  Moreover,
  4878 locale operations (renaming and type / term instantiation) are applied
  4879 to attribute arguments as expected.
  4880 
  4881 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4882 actual attributes; rare situations may require Attrib.attribute to
  4883 embed those attributes into Attrib.src that lack concrete syntax.
  4884 Attribute implementations need to cooperate properly with the static
  4885 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4886 Attrib.XXX_thm etc. already do the right thing without further
  4887 intervention.  Only unusual applications -- such as "where" or "of"
  4888 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4889 on the context and the facts involved -- may have to assign parsed
  4890 values to argument tokens explicitly.
  4891 
  4892 * Changed parameter management in theorem generation for long goal
  4893 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4894 theorem statement in rare situations.
  4895 
  4896 * Locale inspection command 'print_locale' omits notes elements.  Use
  4897 'print_locale!' to have them included in the output.
  4898 
  4899 
  4900 *** Provers ***
  4901 
  4902 * Provers/hypsubst.ML: improved version of the subst method, for
  4903 single-step rewriting: it now works in bound variable contexts. New is
  4904 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4905 rewrite a different subterm than the original subst method, which is
  4906 still available as 'simplesubst'.
  4907 
  4908 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4909 and quasi orders.
  4910 
  4911 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4912 reflexive-transitive closure of relations.
  4913 
  4914 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4915 limit (previously hard-coded with a value of 20) user-definable.
  4916 
  4917 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4918 is peformed already.  Object-logics merely need to finish their
  4919 initial simpset configuration as before.  INCOMPATIBILITY.
  4920 
  4921 
  4922 *** HOL ***
  4923 
  4924 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4925 
  4926   syntax (epsilon)
  4927     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4928 
  4929 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4930 and x-symbol; use option '-m epsilon' to get it actually printed.
  4931 Moreover, the mathematically important symbolic identifier \<epsilon>
  4932 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4933 
  4934 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  4935 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  4936 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  4937 support corresponding Isar calculations.
  4938 
  4939 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  4940 instead of ":".
  4941 
  4942 * theory SetInterval: changed the syntax for open intervals:
  4943 
  4944   Old       New
  4945   {..n(}    {..<n}
  4946   {)n..}    {n<..}
  4947   {m..n(}   {m..<n}
  4948   {)m..n}   {m<..n}
  4949   {)m..n(}  {m<..<n}
  4950 
  4951 The old syntax is still supported but will disappear in the next
  4952 release.  For conversion use the following Emacs search and replace
  4953 patterns (these are not perfect but work quite well):
  4954 
  4955   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  4956   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  4957 
  4958 * Theory Commutative_Ring (in Library): method comm_ring for proving
  4959 equalities in commutative rings; method 'algebra' provides a generic
  4960 interface.
  4961 
  4962 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  4963 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  4964 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  4965 be a tuple pattern.
  4966 
  4967 Some new syntax forms are available:
  4968 
  4969   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  4970   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  4971   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  4972   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  4973 
  4974 The latter form "\<Sum>x < k. e" used to be based on a separate
  4975 function "Summation", which has been discontinued.
  4976 
  4977 * theory Finite_Set: in structured induction proofs, the insert case
  4978 is now 'case (insert x F)' instead of the old counterintuitive 'case
  4979 (insert F x)'.
  4980 
  4981 * The 'refute' command has been extended to support a much larger
  4982 fragment of HOL, including axiomatic type classes, constdefs and
  4983 typedefs, inductive datatypes and recursion.
  4984 
  4985 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  4986 Requires zChaff with proof generation to be installed.  See
  4987 HOL/ex/SAT_Examples.thy for examples.
  4988 
  4989 * Datatype induction via method 'induct' now preserves the name of the
  4990 induction variable. For example, when proving P(xs::'a list) by
  4991 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  4992 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  4993 in unstructured proof scripts.
  4994 
  4995 * Reworked implementation of records.  Improved scalability for
  4996 records with many fields, avoiding performance problems for type
  4997 inference. Records are no longer composed of nested field types, but
  4998 of nested extension types. Therefore the record type only grows linear
  4999 in the number of extensions and not in the number of fields.  The
  5000 top-level (users) view on records is preserved.  Potential
  5001 INCOMPATIBILITY only in strange cases, where the theory depends on the
  5002 old record representation. The type generated for a record is called
  5003 <record_name>_ext_type.
  5004 
  5005 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  5006 proofs triggered by a record definition or a simproc (if
  5007 quick_and_dirty is enabled).  Definitions of large records can take
  5008 quite long.
  5009 
  5010 New simproc record_upd_simproc for simplification of multiple record
  5011 updates enabled by default.  Moreover, trivial updates are also
  5012 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  5013 occasionally, since simplification is more powerful by default.
  5014 
  5015 * typedef: proper support for polymorphic sets, which contain extra
  5016 type-variables in the term.
  5017 
  5018 * Simplifier: automatically reasons about transitivity chains
  5019 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  5020 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  5021 old proofs break occasionally as simplification may now solve more
  5022 goals than previously.
  5023 
  5024 * Simplifier: converts x <= y into x = y if assumption y <= x is
  5025 present.  Works for all partial orders (class "order"), in particular
  5026 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  5027 just like y <= x.
  5028 
  5029 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  5030 bound variable or a constant then the let is unfolded.  Otherwise
  5031 first a is simplified to b, and then f b is simplified to g. If
  5032 possible we abstract b from g arriving at "let x = b in h x",
  5033 otherwise we unfold the let and arrive at g.  The simproc can be
  5034 enabled/disabled by the reference use_let_simproc.  Potential
  5035 INCOMPATIBILITY since simplification is more powerful by default.
  5036 
  5037 * Classical reasoning: the meson method now accepts theorems as arguments.
  5038 
  5039 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  5040 jobs to provide advice on the provability of subgoals.
  5041 
  5042 * Theory OrderedGroup and Ring_and_Field: various additions and
  5043 improvements to faciliate calculations involving equalities and
  5044 inequalities.
  5045 
  5046 The following theorems have been eliminated or modified
  5047 (INCOMPATIBILITY):
  5048 
  5049   abs_eq             now named abs_of_nonneg
  5050   abs_of_ge_0        now named abs_of_nonneg
  5051   abs_minus_eq       now named abs_of_nonpos
  5052   imp_abs_id         now named abs_of_nonneg
  5053   imp_abs_neg_id     now named abs_of_nonpos
  5054   mult_pos           now named mult_pos_pos
  5055   mult_pos_le        now named mult_nonneg_nonneg
  5056   mult_pos_neg_le    now named mult_nonneg_nonpos
  5057   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5058   mult_neg           now named mult_neg_neg
  5059   mult_neg_le        now named mult_nonpos_nonpos
  5060 
  5061 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5062      
  5063      zero_le_square
  5064      not_square_less_zero 
  5065 
  5066   The following lemmas have been deleted from Real/RealPow:
  5067   
  5068      realpow_zero_zero
  5069      realpow_two
  5070      realpow_less
  5071      zero_le_power
  5072      realpow_two_le
  5073      abs_realpow_two
  5074      realpow_two_abs     
  5075 
  5076 * Theory Parity: added rules for simplifying exponents.
  5077 
  5078 * Theory List:
  5079 
  5080 The following theorems have been eliminated or modified
  5081 (INCOMPATIBILITY):
  5082 
  5083   list_all_Nil       now named list_all.simps(1)
  5084   list_all_Cons      now named list_all.simps(2)
  5085   list_all_conv      now named list_all_iff
  5086   set_mem_eq         now named mem_iff
  5087 
  5088 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5089 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5090 
  5091 
  5092 *** HOL-Complex ***
  5093 
  5094 * Theory RealDef: better support for embedding natural numbers and
  5095 integers in the reals.
  5096 
  5097 The following theorems have been eliminated or modified
  5098 (INCOMPATIBILITY):
  5099 
  5100   exp_ge_add_one_self  now requires no hypotheses
  5101   real_of_int_add      reversed direction of equality (use [symmetric])
  5102   real_of_int_minus    reversed direction of equality (use [symmetric])
  5103   real_of_int_diff     reversed direction of equality (use [symmetric])
  5104   real_of_int_mult     reversed direction of equality (use [symmetric])
  5105 
  5106 * Theory RComplete: expanded support for floor and ceiling functions.
  5107 
  5108 * Theory Ln is new, with properties of the natural logarithm
  5109 
  5110 * Hyperreal: There is a new type constructor "star" for making
  5111 nonstandard types.  The old type names are now type synonyms:
  5112 
  5113   hypreal = real star
  5114   hypnat = nat star
  5115   hcomplex = complex star
  5116 
  5117 * Hyperreal: Many groups of similarly-defined constants have been
  5118 replaced by polymorphic versions (INCOMPATIBILITY):
  5119 
  5120   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5121 
  5122   starset      <-- starsetNat, starsetC
  5123   *s*          <-- *sNat*, *sc*
  5124   starset_n    <-- starsetNat_n, starsetC_n
  5125   *sn*         <-- *sNatn*, *scn*
  5126   InternalSets <-- InternalNatSets, InternalCSets
  5127 
  5128   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5129   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5130   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5131   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5132   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5133 
  5134 * Hyperreal: Many type-specific theorems have been removed in favor of
  5135 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5136 
  5137   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5138   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5139   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5140   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5141   right_minus <-- hypreal_add_minus
  5142   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5143   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5144   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5145   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5146   mult_1_right <-- hcomplex_mult_one_right
  5147   mult_zero_left <-- hcomplex_mult_zero_left
  5148   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5149   right_distrib <-- hypnat_add_mult_distrib2
  5150   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5151   right_inverse <-- hypreal_mult_inverse
  5152   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5153   order_refl <-- {hypreal,hypnat}_le_refl
  5154   order_trans <-- {hypreal,hypnat}_le_trans
  5155   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5156   order_less_le <-- {hypreal,hypnat}_less_le
  5157   linorder_linear <-- {hypreal,hypnat}_le_linear
  5158   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5159   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5160   add_nonneg_nonneg <-- hypreal_le_add_order
  5161 
  5162 * Hyperreal: Separate theorems having to do with type-specific
  5163 versions of constants have been merged into theorems that apply to the
  5164 new polymorphic constants (INCOMPATIBILITY):
  5165 
  5166   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5167   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5168   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5169   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5170   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5171   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5172   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5173   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5174   STAR_diff <-- {STAR,STARC}_diff
  5175   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5176     STARC_hcomplex_of_complex}_image_subset
  5177   starset_n_Un <-- starset{Nat,C}_n_Un
  5178   starset_n_Int <-- starset{Nat,C}_n_Int
  5179   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5180   starset_n_diff <-- starset{Nat,C}_n_diff
  5181   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5182   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5183   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5184   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5185   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5186   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5187   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5188   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5189   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5190   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5191   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5192   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5193   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5194   starfun_diff <-- starfun{C,RC,CR}_diff
  5195   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5196   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5197   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5198   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5199   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5200   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5201   starfun_Id <-- starfunC_Id
  5202   starfun_approx <-- starfun{Nat,CR}_approx
  5203   starfun_capprox <-- starfun{C,RC}_capprox
  5204   starfun_abs <-- starfunNat_rabs
  5205   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5206   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5207   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5208   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5209   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5210   starfun_add_approx <-- starfunCR_add_approx
  5211   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5212   starfun_divide <-- starfun{C,CR,RC}_divide
  5213   starfun_n <-- starfun{Nat,C}_n
  5214   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5215   starfun_n_add <-- starfun{Nat,C}_n_add
  5216   starfun_n_add_minus <-- starfunNat_n_add_minus
  5217   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5218   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5219   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5220 
  5221   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5222   star_n_minus <-- {hypreal,hcomplex}_minus
  5223   star_n_diff <-- {hypreal,hcomplex}_diff
  5224   star_n_mult <-- {hypreal,hcomplex}_mult
  5225   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5226   star_n_le <-- {hypreal,hypnat}_le
  5227   star_n_less <-- {hypreal,hypnat}_less
  5228   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5229   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5230   star_n_abs <-- hypreal_hrabs
  5231   star_n_divide <-- hcomplex_divide
  5232 
  5233   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5234   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5235   star_of_diff <-- hypreal_of_real_diff
  5236   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5237   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5238   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5239   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5240   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5241   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5242   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5243   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5244   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5245   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5246   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5247   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5248   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5249   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5250   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5251   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5252   star_of_power <-- hypreal_of_real_power
  5253   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5254 
  5255 * Hyperreal: new method "transfer" that implements the transfer
  5256 principle of nonstandard analysis. With a subgoal that mentions
  5257 nonstandard types like "'a star", the command "apply transfer"
  5258 replaces it with an equivalent one that mentions only standard types.
  5259 To be successful, all free variables must have standard types; non-
  5260 standard variables must have explicit universal quantifiers.
  5261 
  5262 * Hyperreal: A theory of Taylor series.
  5263 
  5264 
  5265 *** HOLCF ***
  5266 
  5267 * Discontinued special version of 'constdefs' (which used to support
  5268 continuous functions) in favor of the general Pure one with full
  5269 type-inference.
  5270 
  5271 * New simplification procedure for solving continuity conditions; it
  5272 is much faster on terms with many nested lambda abstractions (cubic
  5273 instead of exponential time).
  5274 
  5275 * New syntax for domain package: selector names are now optional.
  5276 Parentheses should be omitted unless argument is lazy, for example:
  5277 
  5278   domain 'a stream = cons "'a" (lazy "'a stream")
  5279 
  5280 * New command 'fixrec' for defining recursive functions with pattern
  5281 matching; defining multiple functions with mutual recursion is also
  5282 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5283 sinr, or any data constructor defined by the domain package. The given
  5284 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5285 syntax and examples.
  5286 
  5287 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5288 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5289 but the proof obligation additionally includes an admissibility
  5290 requirement. The packages generate instances of class cpo or pcpo,
  5291 with continuity and strictness theorems for Rep and Abs.
  5292 
  5293 * HOLCF: Many theorems have been renamed according to a more standard naming
  5294 scheme (INCOMPATIBILITY):
  5295 
  5296   foo_inject:  "foo$x = foo$y ==> x = y"
  5297   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5298   foo_less:    "(foo$x << foo$y) = (x << y)"
  5299   foo_strict:  "foo$UU = UU"
  5300   foo_defined: "... ==> foo$x ~= UU"
  5301   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5302 
  5303 
  5304 *** ZF ***
  5305 
  5306 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5307 including the First Isomorphism Theorem (on quotienting by the kernel
  5308 of a homomorphism).
  5309 
  5310 * ZF/Simplifier: install second copy of type solver that actually
  5311 makes use of TC rules declared to Isar proof contexts (or locales);
  5312 the old version is still required for ML proof scripts.
  5313 
  5314 
  5315 *** Cube ***
  5316 
  5317 * Converted to Isar theory format; use locales instead of axiomatic
  5318 theories.
  5319 
  5320 
  5321 *** ML ***
  5322 
  5323 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5324 for ||>, ||>>, |>>,
  5325 
  5326 * Pure/library.ML no longer defines its own option datatype, but uses
  5327 that of the SML basis, which has constructors NONE and SOME instead of
  5328 None and Some, as well as exception Option.Option instead of OPTION.
  5329 The functions the, if_none, is_some, is_none have been adapted
  5330 accordingly, while Option.map replaces apsome.
  5331 
  5332 * Pure/library.ML: the exception LIST has been given up in favour of
  5333 the standard exceptions Empty and Subscript, as well as
  5334 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5335 superceded by the standard hd and tl functions etc.
  5336 
  5337 A number of basic list functions are no longer exported to the ML
  5338 toplevel, as they are variants of predefined functions.  The following
  5339 suggests how one can translate existing code:
  5340 
  5341     rev_append xs ys = List.revAppend (xs, ys)
  5342     nth_elem (i, xs) = List.nth (xs, i)
  5343     last_elem xs = List.last xs
  5344     flat xss = List.concat xss
  5345     seq fs = List.app fs
  5346     partition P xs = List.partition P xs
  5347     mapfilter f xs = List.mapPartial f xs
  5348 
  5349 * Pure/library.ML: several combinators for linear functional
  5350 transformations, notably reverse application and composition:
  5351 
  5352   x |> f                f #> g
  5353   (x, y) |-> f          f #-> g
  5354 
  5355 * Pure/library.ML: introduced/changed precedence of infix operators:
  5356 
  5357   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5358   infix 2 ?;
  5359   infix 3 o oo ooo oooo;
  5360   infix 4 ~~ upto downto;
  5361 
  5362 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5363 infix operators.
  5364 
  5365 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5366 fold_map support linear functional transformations and nesting.  For
  5367 example:
  5368 
  5369   fold f [x1, ..., xN] y =
  5370     y |> f x1 |> ... |> f xN
  5371 
  5372   (fold o fold) f [xs1, ..., xsN] y =
  5373     y |> fold f xs1 |> ... |> fold f xsN
  5374 
  5375   fold f [x1, ..., xN] =
  5376     f x1 #> ... #> f xN
  5377 
  5378   (fold o fold) f [xs1, ..., xsN] =
  5379     fold f xs1 #> ... #> fold f xsN
  5380 
  5381 * Pure/library.ML: the following selectors on type 'a option are
  5382 available:
  5383 
  5384   the:               'a option -> 'a  (*partial*)
  5385   these:             'a option -> 'a  where 'a = 'b list
  5386   the_default: 'a -> 'a option -> 'a
  5387   the_list:          'a option -> 'a list
  5388 
  5389 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5390 basic operations for association lists, following natural argument
  5391 order; moreover the explicit equality predicate passed here avoids
  5392 potentially expensive polymorphic runtime equality checks.
  5393 The old functions may be expressed as follows:
  5394 
  5395   assoc = uncurry (AList.lookup (op =))
  5396   assocs = these oo AList.lookup (op =)
  5397   overwrite = uncurry (AList.update (op =)) o swap
  5398 
  5399 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5400 
  5401   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5402   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5403 
  5404 replacing make_keylist and keyfilter (occassionally used)
  5405 Naive rewrites:
  5406 
  5407   make_keylist = AList.make
  5408   keyfilter = AList.find (op =)
  5409 
  5410 * eq_fst and eq_snd now take explicit equality parameter, thus
  5411   avoiding eqtypes. Naive rewrites:
  5412 
  5413     eq_fst = eq_fst (op =)
  5414     eq_snd = eq_snd (op =)
  5415 
  5416 * Removed deprecated apl and apr (rarely used).
  5417   Naive rewrites:
  5418 
  5419     apl (n, op) =>>= curry op n
  5420     apr (op, m) =>>= fn n => op (n, m)
  5421 
  5422 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5423 provides a reasonably efficient light-weight implementation of sets as
  5424 lists.
  5425 
  5426 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5427 few new operations; existing lookup and update are now curried to
  5428 follow natural argument order (for use with fold etc.);
  5429 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5430 
  5431 * Pure/General: output via the Isabelle channels of
  5432 writeln/warning/error etc. is now passed through Output.output, with a
  5433 hook for arbitrary transformations depending on the print_mode
  5434 (cf. Output.add_mode -- the first active mode that provides a output
  5435 function wins).  Already formatted output may be embedded into further
  5436 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5437 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5438 accommodate easy composition of diagnostic messages etc.  Programmers
  5439 rarely need to care about Output.output or Output.raw at all, with
  5440 some notable exceptions: Output.output is required when bypassing the
  5441 standard channels (writeln etc.), or in token translations to produce
  5442 properly formatted results; Output.raw is required when capturing
  5443 already output material that will eventually be presented to the user
  5444 a second time.  For the default print mode, both Output.output and
  5445 Output.raw have no effect.
  5446 
  5447 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5448 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5449 cumulative results are displayed at the end of a batch session.
  5450 
  5451 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5452 replaced by File.platform_path and File.shell_path (with appropriate
  5453 hooks).  This provides a clean interface for unusual systems where the
  5454 internal and external process view of file names are different.
  5455 
  5456 * Pure: more efficient orders for basic syntactic entities: added
  5457 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5458 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5459 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5460 orders now -- potential INCOMPATIBILITY for code that depends on a
  5461 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5462 Library.sort_strings on result).
  5463 
  5464 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5465 fold_types traverse types/terms from left to right, observing natural
  5466 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5467 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5468 
  5469 * Pure: name spaces have been refined, with significant changes of the
  5470 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5471 to extern(_table).  The plain name entry path is superceded by a
  5472 general 'naming' context, which also includes the 'policy' to produce
  5473 a fully qualified name and external accesses of a fully qualified
  5474 name; NameSpace.extend is superceded by context dependent
  5475 Sign.declare_name.  Several theory and proof context operations modify
  5476 the naming context.  Especially note Theory.restore_naming and
  5477 ProofContext.restore_naming to get back to a sane state; note that
  5478 Theory.add_path is no longer sufficient to recover from
  5479 Theory.absolute_path in particular.
  5480 
  5481 * Pure: new flags short_names (default false) and unique_names
  5482 (default true) for controlling output of qualified names.  If
  5483 short_names is set, names are printed unqualified.  If unique_names is
  5484 reset, the name prefix is reduced to the minimum required to achieve
  5485 the original result when interning again, even if there is an overlap
  5486 with earlier declarations.
  5487 
  5488 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5489 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5490 (useful for printing error messages).  INCOMPATIBILITY.
  5491 
  5492 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5493 Theory.theory are now identified, referring to the universal
  5494 Context.theory (see Pure/context.ML).  Actual signature and theory
  5495 content is managed as theory data.  The old code and interfaces were
  5496 spread over many files and structures; the new arrangement introduces
  5497 considerable INCOMPATIBILITY to gain more clarity:
  5498 
  5499   Context -- theory management operations (name, identity, inclusion,
  5500     parents, ancestors, merge, etc.), plus generic theory data;
  5501 
  5502   Sign -- logical signature and syntax operations (declaring consts,
  5503     types, etc.), plus certify/read for common entities;
  5504 
  5505   Theory -- logical theory operations (stating axioms, definitions,
  5506     oracles), plus a copy of logical signature operations (consts,
  5507     types, etc.); also a few basic management operations (Theory.copy,
  5508     Theory.merge, etc.)
  5509 
  5510 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5511 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5512 for convenience -- they merely return the theory.
  5513 
  5514 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5515 
  5516 * Pure: the Isar proof context type is already defined early in Pure
  5517 as Context.proof (note that ProofContext.context and Proof.context are
  5518 aliases, where the latter is the preferred name).  This enables other
  5519 Isabelle components to refer to that type even before Isar is present.
  5520 
  5521 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5522 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5523 any of these kinds.  For example, Sign.intern typeK is now
  5524 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5525 Theory.hide_types.  Also note that former
  5526 Theory.hide_classes/types/consts are now
  5527 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5528 internalize their arguments!  INCOMPATIBILITY.
  5529 
  5530 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5531 datatype thmref (with constructors Name and NameSelection) instead of
  5532 plain string -- INCOMPATIBILITY;
  5533 
  5534 * Pure: cases produced by proof methods specify options, where NONE
  5535 means to remove case bindings -- INCOMPATIBILITY in
  5536 (RAW_)METHOD_CASES.
  5537 
  5538 * Pure: the following operations retrieve axioms or theorems from a
  5539 theory node or theory hierarchy, respectively:
  5540 
  5541   Theory.axioms_of: theory -> (string * term) list
  5542   Theory.all_axioms_of: theory -> (string * term) list
  5543   PureThy.thms_of: theory -> (string * thm) list
  5544   PureThy.all_thms_of: theory -> (string * thm) list
  5545 
  5546 * Pure: print_tac now outputs the goal through the trace channel.
  5547 
  5548 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5549 Reference Toplevel.debug (default false) controls detailed printing
  5550 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5551 controls execution profiling -- set to 1 for time and 2 for space
  5552 (both increase the runtime).
  5553 
  5554 * Isar session: The initial use of ROOT.ML is now always timed,
  5555 i.e. the log will show the actual process times, in contrast to the
  5556 elapsed wall-clock time that the outer shell wrapper produces.
  5557 
  5558 * Simplifier: improved handling of bound variables (nameless
  5559 representation, avoid allocating new strings).  Simprocs that invoke
  5560 the Simplifier recursively should use Simplifier.inherit_bounds to
  5561 avoid local name clashes.  Failure to do so produces warnings
  5562 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5563 for further details.
  5564 
  5565 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5566 bindings for all theorems stored within a given theory; this may help
  5567 in porting non-Isar theories to Isar ones, while keeping ML proof
  5568 scripts for the time being.
  5569 
  5570 * ML operator HTML.with_charset specifies the charset begin used for
  5571 generated HTML files.  For example:
  5572 
  5573   HTML.with_charset "utf-8" use_thy "Hebrew";
  5574   HTML.with_charset "utf-8" use_thy "Chinese";
  5575 
  5576 
  5577 *** System ***
  5578 
  5579 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5580 isabelle, isatool etc.).
  5581 
  5582 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5583 isatool doc, isatool mkdir, display_drafts etc.).
  5584 
  5585 * isatool usedir: option -f allows specification of the ML file to be
  5586 used by Isabelle; default is ROOT.ML.
  5587 
  5588 * New isatool version outputs the version identifier of the Isabelle
  5589 distribution being used.
  5590 
  5591 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5592 (containing Boolean satisfiability problems) into Isabelle/HOL
  5593 theories.
  5594 
  5595 
  5596 
  5597 New in Isabelle2004 (April 2004)
  5598 --------------------------------
  5599 
  5600 *** General ***
  5601 
  5602 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5603   Replaces linorder.ML.
  5604 
  5605 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5606   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5607   (\<a>...\<z>), are now considered normal letters, and can therefore
  5608   be used anywhere where an ASCII letter (a...zA...Z) has until
  5609   now. COMPATIBILITY: This obviously changes the parsing of some
  5610   terms, especially where a symbol has been used as a binder, say
  5611   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5612   as an identifier.  Fix it by inserting a space around former
  5613   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5614   existing theory and ML files.
  5615 
  5616 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5617 
  5618 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5619   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5620   a normal (but invisible) letter. For multiple letter subscripts repeat
  5621   \<^isub> like this: x\<^isub>1\<^isub>2.
  5622 
  5623 * Pure: There are now sub-/superscripts that can span more than one
  5624   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5625   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5626   superscript. The new control characters are not identifier parts.
  5627 
  5628 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5629   content of "..." to the latex file instead of \isacntrl... . The "..."
  5630   may consist of any printable characters excluding the end bracket >.
  5631 
  5632 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5633   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5634   declare constants "final", which prevents their being given a definition
  5635   later.  It is useful for constants whose behaviour is fixed axiomatically
  5636   rather than definitionally, such as the meta-logic connectives.
  5637 
  5638 * Pure: 'instance' now handles general arities with general sorts
  5639   (i.e. intersections of classes),
  5640 
  5641 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5642   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5643   It can be changed to alter the colors/layout of generated pages.
  5644 
  5645 
  5646 *** Isar ***
  5647 
  5648 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5649   cut_tac, subgoal_tac and thin_tac:
  5650   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5651     locales are no longer forced to write Isar proof scripts.
  5652     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5653     emulations.
  5654   - INCOMPATIBILITY: names of variables to be instantiated may no
  5655     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5656     This is consistent with the instantiation attribute "where".
  5657 
  5658 * Attributes "where" and "of":
  5659   - Now take type variables of instantiated theorem into account when reading
  5660     the instantiation string.  This fixes a bug that caused instantiated
  5661     theorems to have too special types in some circumstances.
  5662   - "where" permits explicit instantiations of type variables.
  5663 
  5664 * Calculation commands "moreover" and "also" no longer interfere with
  5665   current facts ("this"), admitting arbitrary combinations with "then"
  5666   and derived forms.
  5667 
  5668 * Locales:
  5669   - Goal statements involving the context element "includes" no longer
  5670     generate theorems with internal delta predicates (those ending on
  5671     "_axioms") in the premise.
  5672     Resolve particular premise with <locale>.intro to obtain old form.
  5673   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5674     specification and "includes" elements in goal statement.
  5675   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5676     [intro?] and [elim?] (respectively) by default.
  5677   - Experimental command for instantiation of locales in proof contexts:
  5678         instantiate <label>[<attrs>]: <loc>
  5679     Instantiates locale <loc> and adds all its theorems to the current context
  5680     taking into account their attributes.  Label and attrs are optional
  5681     modifiers, like in theorem declarations.  If present, names of
  5682     instantiated theorems are qualified with <label>, and the attributes
  5683     <attrs> are applied after any attributes these theorems might have already.
  5684       If the locale has assumptions, a chained fact of the form
  5685     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5686     are derived.  The command does not support old-style locales declared
  5687     with "locale (open)".
  5688       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5689 
  5690 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5691   (Isar) contexts.
  5692 
  5693 
  5694 *** HOL ***
  5695 
  5696 * Proof import: new image HOL4 contains the imported library from
  5697   the HOL4 system with about 2500 theorems. It is imported by
  5698   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5699   can be used like any other Isabelle image.  See
  5700   HOL/Import/HOL/README for more information.
  5701 
  5702 * Simplifier:
  5703   - Much improved handling of linear and partial orders.
  5704     Reasoners for linear and partial orders are set up for type classes
  5705     "linorder" and "order" respectively, and are added to the default simpset
  5706     as solvers.  This means that the simplifier can build transitivity chains
  5707     to solve goals from the assumptions.
  5708   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5709     of blast or auto after simplification become unnecessary because the goal
  5710     is solved by simplification already.
  5711 
  5712 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5713     all proved in axiomatic type classes for semirings, rings and fields.
  5714 
  5715 * Numerics:
  5716   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5717     now formalized using the Ring_and_Field theory mentioned above.
  5718   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5719     than before, because now they are set up once in a generic manner.
  5720   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5721     Look for the general versions in Ring_and_Field (and Power if they concern
  5722     exponentiation).
  5723 
  5724 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5725 
  5726 * Records:
  5727   - Record types are now by default printed with their type abbreviation
  5728     instead of the list of all field types. This can be configured via
  5729     the reference "print_record_type_abbr".
  5730   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5731     (not enabled by default).
  5732   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5733     EX x. x = sel r to True (not enabled by default).
  5734   - Tactic "record_split_simp_tac" to split and simplify records added.
  5735 
  5736 * 'specification' command added, allowing for definition by
  5737   specification.  There is also an 'ax_specification' command that
  5738   introduces the new constants axiomatically.
  5739 
  5740 * arith(_tac) is now able to generate counterexamples for reals as well.
  5741 
  5742 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5743 
  5744 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5745   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5746 
  5747 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5748   matrix theory to linear programming.
  5749 
  5750 * Unions and Intersections:
  5751   The latex output syntax of UN and INT has been changed
  5752   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5753   i.e. the index formulae has become a subscript.
  5754   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5755 
  5756 * Unions and Intersections over Intervals:
  5757   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5758   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5759   like in normal math, and corresponding versions for < and for intersection.
  5760 
  5761 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5762   lexicographic dictonary ordering has been added as "lexord".
  5763 
  5764 * ML: the legacy theory structures Int and List have been removed. They had
  5765   conflicted with ML Basis Library structures having the same names.
  5766 
  5767 * 'refute' command added to search for (finite) countermodels.  Only works
  5768   for a fragment of HOL.  The installation of an external SAT solver is
  5769   highly recommended.  See "HOL/Refute.thy" for details.
  5770 
  5771 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5772   formulae under an assignment of free variables to random values.
  5773   In contrast to 'refute', it can deal with inductive datatypes,
  5774   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5775   for examples.
  5776 
  5777 
  5778 *** HOLCF ***
  5779 
  5780 * Streams now come with concatenation and are part of the HOLCF image
  5781 
  5782 
  5783 
  5784 New in Isabelle2003 (May 2003)
  5785 ------------------------------
  5786 
  5787 *** General ***
  5788 
  5789 * Provers/simplifier:
  5790 
  5791   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5792     Assumptions are now subject to complete mutual simplification,
  5793     not just from left to right. The simplifier now preserves
  5794     the order of assumptions.
  5795 
  5796     Potential INCOMPATIBILITY:
  5797 
  5798     -- simp sometimes diverges where the old version did
  5799        not, e.g. invoking simp on the goal
  5800 
  5801         [| P (f x); y = x; f x = f y |] ==> Q
  5802 
  5803        now gives rise to the infinite reduction sequence
  5804 
  5805         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5806 
  5807        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5808        kind of problem.
  5809 
  5810     -- Tactics combining classical reasoner and simplification (such as auto)
  5811        are also affected by this change, because many of them rely on
  5812        simp. They may sometimes diverge as well or yield a different numbers
  5813        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5814        in case of problems. Sometimes subsequent calls to the classical
  5815        reasoner will fail because a preceeding call to the simplifier too
  5816        eagerly simplified the goal, e.g. deleted redundant premises.
  5817 
  5818   - The simplifier trace now shows the names of the applied rewrite rules
  5819 
  5820   - You can limit the number of recursive invocations of the simplifier
  5821     during conditional rewriting (where the simplifie tries to solve the
  5822     conditions before applying the rewrite rule):
  5823     ML "simp_depth_limit := n"
  5824     where n is an integer. Thus you can force termination where previously
  5825     the simplifier would diverge.
  5826 
  5827   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5828 
  5829   - No longer aborts on failed congruence proof.  Instead, the
  5830     congruence is ignored.
  5831 
  5832 * Pure: New generic framework for extracting programs from constructive
  5833   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5834   as HOL/Extraction for some case studies.
  5835 
  5836 * Pure: The main goal of the proof state is no longer shown by default, only
  5837 the subgoals. This behaviour is controlled by a new flag.
  5838    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5839 (ML: Proof.show_main_goal).
  5840 
  5841 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5842 rules whose conclusion matches subgoal 1:
  5843       PG menu: Isabelle/Isar -> Show me -> matching rules
  5844 The rules are ordered by how closely they match the subgoal.
  5845 In particular, rules that solve a subgoal outright are displayed first
  5846 (or rather last, the way they are printed).
  5847 (ML: ProofGeneral.print_intros())
  5848 
  5849 * Pure: New flag trace_unify_fail causes unification to print
  5850 diagnostic information (PG: in trace buffer) when it fails. This is
  5851 useful for figuring out why single step proofs like rule, erule or
  5852 assumption failed.
  5853 
  5854 * Pure: Locale specifications now produce predicate definitions
  5855 according to the body of text (covering assumptions modulo local
  5856 definitions); predicate "loc_axioms" covers newly introduced text,
  5857 while "loc" is cumulative wrt. all included locale expressions; the
  5858 latter view is presented only on export into the global theory
  5859 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5860 on the old view without predicates;
  5861 
  5862 * Pure: predefined locales "var" and "struct" are useful for sharing
  5863 parameters (as in CASL, for example); just specify something like
  5864 ``var x + var y + struct M'' as import;
  5865 
  5866 * Pure: improved thms_containing: proper indexing of facts instead of
  5867 raw theorems; check validity of results wrt. current name space;
  5868 include local facts of proof configuration (also covers active
  5869 locales), cover fixed variables in index; may use "_" in term
  5870 specification; an optional limit for the number of printed facts may
  5871 be given (the default is 40);
  5872 
  5873 * Pure: disallow duplicate fact bindings within new-style theory files
  5874 (batch-mode only);
  5875 
  5876 * Provers: improved induct method: assumptions introduced by case
  5877 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5878 the goal statement); "foo" still refers to all facts collectively;
  5879 
  5880 * Provers: the function blast.overloaded has been removed: all constants
  5881 are regarded as potentially overloaded, which improves robustness in exchange
  5882 for slight decrease in efficiency;
  5883 
  5884 * Provers/linorder: New generic prover for transitivity reasoning over
  5885 linear orders.  Note: this prover is not efficient!
  5886 
  5887 * Isar: preview of problems to finish 'show' now produce an error
  5888 rather than just a warning (in interactive mode);
  5889 
  5890 
  5891 *** HOL ***
  5892 
  5893 * arith(_tac)
  5894 
  5895  - Produces a counter example if it cannot prove a goal.
  5896    Note that the counter example may be spurious if the goal is not a formula
  5897    of quantifier-free linear arithmetic.
  5898    In ProofGeneral the counter example appears in the trace buffer.
  5899 
  5900  - Knows about div k and mod k where k is a numeral of type nat or int.
  5901 
  5902  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5903    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5904    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5905 
  5906 * simp's arithmetic capabilities have been enhanced a bit: it now
  5907 takes ~= in premises into account (by performing a case split);
  5908 
  5909 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5910 are distributed over a sum of terms;
  5911 
  5912 * New tactic "trans_tac" and method "trans" instantiate
  5913 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5914 "<=", "<" and "=").
  5915 
  5916 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5917 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5918 
  5919 * 'typedef' command has new option "open" to suppress the set
  5920 definition;
  5921 
  5922 * functions Min and Max on finite sets have been introduced (theory
  5923 Finite_Set);
  5924 
  5925 * attribute [symmetric] now works for relations as well; it turns
  5926 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5927 
  5928 * induct over a !!-quantified statement (say !!x1..xn):
  5929   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5930 
  5931 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5932 %x. None. Warning: empty_def now refers to the previously hidden definition
  5933 of the empty set.
  5934 
  5935 * Algebra: formalization of classical algebra.  Intended as base for
  5936 any algebraic development in Isabelle.  Currently covers group theory
  5937 (up to Sylow's theorem) and ring theory (Universal Property of
  5938 Univariate Polynomials).  Contributions welcome;
  5939 
  5940 * GroupTheory: deleted, since its material has been moved to Algebra;
  5941 
  5942 * Complex: new directory of the complex numbers with numeric constants,
  5943 nonstandard complex numbers, and some complex analysis, standard and
  5944 nonstandard (Jacques Fleuriot);
  5945 
  5946 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  5947 
  5948 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  5949 Fleuriot);
  5950 
  5951 * Real/HahnBanach: updated and adapted to locales;
  5952 
  5953 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  5954 Gray and Kramer);
  5955 
  5956 * UNITY: added the Meier-Sanders theory of progress sets;
  5957 
  5958 * MicroJava: bytecode verifier and lightweight bytecode verifier
  5959 as abstract algorithms, instantiated to the JVM;
  5960 
  5961 * Bali: Java source language formalization. Type system, operational
  5962 semantics, axiomatic semantics. Supported language features:
  5963 classes, interfaces, objects,virtual methods, static methods,
  5964 static/instance fields, arrays, access modifiers, definite
  5965 assignment, exceptions.
  5966 
  5967 
  5968 *** ZF ***
  5969 
  5970 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  5971 universe, etc.);
  5972 
  5973 * Main ZF: virtually all theories converted to new-style format;
  5974 
  5975 
  5976 *** ML ***
  5977 
  5978 * Pure: Tactic.prove provides sane interface for internal proofs;
  5979 omits the infamous "standard" operation, so this is more appropriate
  5980 than prove_goalw_cterm in many situations (e.g. in simprocs);
  5981 
  5982 * Pure: improved error reporting of simprocs;
  5983 
  5984 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  5985 up simprocs;
  5986 
  5987 
  5988 *** Document preparation ***
  5989 
  5990 * uses \par instead of \\ for line breaks in theory text. This may
  5991 shift some page breaks in large documents. To get the old behaviour
  5992 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  5993 
  5994 * minimized dependencies of isabelle.sty and isabellesym.sty on
  5995 other packages
  5996 
  5997 * \<euro> now needs package babel/greek instead of marvosym (which
  5998 broke \Rightarrow)
  5999 
  6000 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  6001 textcomp package)
  6002 
  6003 
  6004 
  6005 New in Isabelle2002 (March 2002)
  6006 --------------------------------
  6007 
  6008 *** Document preparation ***
  6009 
  6010 * greatly simplified document preparation setup, including more
  6011 graceful interpretation of isatool usedir -i/-d/-D options, and more
  6012 instructive isatool mkdir; users should basically be able to get
  6013 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  6014 users may run a separate document processing stage manually like this:
  6015 "isatool usedir -D output HOL Test && isatool document Test/output";
  6016 
  6017 * theory dependency graph may now be incorporated into documents;
  6018 isatool usedir -g true will produce session_graph.eps/.pdf for use
  6019 with \includegraphics of LaTeX;
  6020 
  6021 * proper spacing of consecutive markup elements, especially text
  6022 blocks after section headings;
  6023 
  6024 * support bold style (for single symbols only), input syntax is like
  6025 this: "\<^bold>\<alpha>" or "\<^bold>A";
  6026 
  6027 * \<bullet> is now output as bold \cdot by default, which looks much
  6028 better in printed text;
  6029 
  6030 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  6031 note that these symbols are currently unavailable in Proof General /
  6032 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  6033 
  6034 * isatool latex no longer depends on changed TEXINPUTS, instead
  6035 isatool document copies the Isabelle style files to the target
  6036 location;
  6037 
  6038 
  6039 *** Isar ***
  6040 
  6041 * Pure/Provers: improved proof by cases and induction;
  6042   - 'case' command admits impromptu naming of parameters (such as
  6043     "case (Suc n)");
  6044   - 'induct' method divinates rule instantiation from the inductive
  6045     claim; no longer requires excessive ?P bindings for proper
  6046     instantiation of cases;
  6047   - 'induct' method properly enumerates all possibilities of set/type
  6048     rules; as a consequence facts may be also passed through *type*
  6049     rules without further ado;
  6050   - 'induct' method now derives symbolic cases from the *rulified*
  6051     rule (before it used to rulify cases stemming from the internal
  6052     atomized version); this means that the context of a non-atomic
  6053     statement becomes is included in the hypothesis, avoiding the
  6054     slightly cumbersome show "PROP ?case" form;
  6055   - 'induct' may now use elim-style induction rules without chaining
  6056     facts, using ``missing'' premises from the goal state; this allows
  6057     rules stemming from inductive sets to be applied in unstructured
  6058     scripts, while still benefitting from proper handling of non-atomic
  6059     statements; NB: major inductive premises need to be put first, all
  6060     the rest of the goal is passed through the induction;
  6061   - 'induct' proper support for mutual induction involving non-atomic
  6062     rule statements (uses the new concept of simultaneous goals, see
  6063     below);
  6064   - append all possible rule selections, but only use the first
  6065     success (no backtracking);
  6066   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  6067   - undeclared rule case names default to numbers 1, 2, 3, ...;
  6068   - added 'print_induct_rules' (covered by help item in recent Proof
  6069     General versions);
  6070   - moved induct/cases attributes to Pure, methods to Provers;
  6071   - generic method setup instantiated for FOL and HOL;
  6072 
  6073 * Pure: support multiple simultaneous goal statements, for example
  6074 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  6075 meta-level mechanism, this acts as if several individual goals had
  6076 been stated separately; in particular common proof methods need to be
  6077 repeated in order to cover all claims; note that a single elimination
  6078 step is *not* sufficient to establish the two conjunctions, so this
  6079 fails:
  6080 
  6081   assume "A & B" then have A and B ..   (*".." fails*)
  6082 
  6083 better use "obtain" in situations as above; alternative refer to
  6084 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  6085 
  6086 * Pure: proper integration with ``locales''; unlike the original
  6087 version by Florian Kammller, Isar locales package high-level proof
  6088 contexts rather than raw logical ones (e.g. we admit to include
  6089 attributes everywhere); operations on locales include merge and
  6090 rename; support for implicit arguments (``structures''); simultaneous
  6091 type-inference over imports and text; see also HOL/ex/Locales.thy for
  6092 some examples;
  6093 
  6094 * Pure: the following commands have been ``localized'', supporting a
  6095 target locale specification "(in name)": 'lemma', 'theorem',
  6096 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  6097 stored both within the locale and at the theory level (exported and
  6098 qualified by the locale name);
  6099 
  6100 * Pure: theory goals may now be specified in ``long'' form, with
  6101 ad-hoc contexts consisting of arbitrary locale elements. for example
  6102 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  6103 definitions may be given, too); the result is a meta-level rule with
  6104 the context elements being discharged in the obvious way;
  6105 
  6106 * Pure: new proof command 'using' allows to augment currently used
  6107 facts after a goal statement ('using' is syntactically analogous to
  6108 'apply', but acts on the goal's facts only); this allows chained facts
  6109 to be separated into parts given before and after a claim, as in
  6110 ``from a and b have C using d and e <proof>'';
  6111 
  6112 * Pure: renamed "antecedent" case to "rule_context";
  6113 
  6114 * Pure: new 'judgment' command records explicit information about the
  6115 object-logic embedding (used by several tools internally); no longer
  6116 use hard-wired "Trueprop";
  6117 
  6118 * Pure: added 'corollary' command;
  6119 
  6120 * Pure: fixed 'token_translation' command;
  6121 
  6122 * Pure: removed obsolete 'exported' attribute;
  6123 
  6124 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  6125 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  6126 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  6127 
  6128 * Pure: method 'atomize' presents local goal premises as object-level
  6129 statements (atomic meta-level propositions); setup controlled via
  6130 rewrite rules declarations of 'atomize' attribute; example
  6131 application: 'induct' method with proper rule statements in improper
  6132 proof *scripts*;
  6133 
  6134 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  6135 now consider the syntactic context of assumptions, giving a better
  6136 chance to get type-inference of the arguments right (this is
  6137 especially important for locales);
  6138 
  6139 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  6140 mode;
  6141 
  6142 * Pure/obtain: the formal conclusion "thesis", being marked as
  6143 ``internal'', may no longer be reference directly in the text;
  6144 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  6145 situations;
  6146 
  6147 * Pure: generic 'sym' attribute which declares a rule both as pure
  6148 'elim?' and for the 'symmetric' operation;
  6149 
  6150 * Pure: marginal comments ``--'' may now occur just anywhere in the
  6151 text; the fixed correlation with particular command syntax has been
  6152 discontinued;
  6153 
  6154 * Pure: new method 'rules' is particularly well-suited for proof
  6155 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  6156 but often produces more compact proof terms with less detours;
  6157 
  6158 * Pure/Provers/classical: simplified integration with pure rule
  6159 attributes and methods; the classical "intro?/elim?/dest?"
  6160 declarations coincide with the pure ones; the "rule" method no longer
  6161 includes classically swapped intros; "intro" and "elim" methods no
  6162 longer pick rules from the context; also got rid of ML declarations
  6163 AddXIs/AddXEs/AddXDs; all of this has some potential for
  6164 INCOMPATIBILITY;
  6165 
  6166 * Provers/classical: attribute 'swapped' produces classical inversions
  6167 of introduction rules;
  6168 
  6169 * Provers/simplifier: 'simplified' attribute may refer to explicit
  6170 rules instead of full simplifier context; 'iff' attribute handles
  6171 conditional rules;
  6172 
  6173 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  6174 
  6175 * HOL: 'recdef' now fails on unfinished automated proofs, use
  6176 "(permissive)" option to recover old behavior;
  6177 
  6178 * HOL: 'inductive' no longer features separate (collective) attributes
  6179 for 'intros' (was found too confusing);
  6180 
  6181 * HOL: properly declared induction rules less_induct and
  6182 wf_induct_rule;
  6183 
  6184 
  6185 *** HOL ***
  6186 
  6187 * HOL: moved over to sane numeral syntax; the new policy is as
  6188 follows:
  6189 
  6190   - 0 and 1 are polymorphic constants, which are defined on any
  6191   numeric type (nat, int, real etc.);
  6192 
  6193   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  6194   binary representation internally;
  6195 
  6196   - type nat has special constructor Suc, and generally prefers Suc 0
  6197   over 1::nat and Suc (Suc 0) over 2::nat;
  6198 
  6199 This change may cause significant problems of INCOMPATIBILITY; here
  6200 are some hints on converting existing sources:
  6201 
  6202   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  6203   entities, so expressions involving "-" (unary or binary minus) need
  6204   to be spaced properly;
  6205 
  6206   - existing occurrences of "1" may need to be constraint "1::nat" or
  6207   even replaced by Suc 0; similar for old "2";
  6208 
  6209   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  6210 
  6211   - remove all special provisions on numerals in proofs;
  6212 
  6213 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  6214 representation (depends on bin_arith_simps in the default context);
  6215 
  6216 * HOL: symbolic syntax for x^2 (numeral 2);
  6217 
  6218 * HOL: the class of all HOL types is now called "type" rather than
  6219 "term"; INCOMPATIBILITY, need to adapt references to this type class
  6220 in axclass/classes, instance/arities, and (usually rare) occurrences
  6221 in typings (of consts etc.); internally the class is called
  6222 "HOL.type", ML programs should refer to HOLogic.typeS;
  6223 
  6224 * HOL/record package improvements:
  6225   - new derived operations "fields" to build a partial record section,
  6226     "extend" to promote a fixed record to a record scheme, and
  6227     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  6228     declared as simp by default;
  6229   - shared operations ("more", "fields", etc.) now need to be always
  6230     qualified) --- potential INCOMPATIBILITY;
  6231   - removed "make_scheme" operations (use "make" with "extend") --
  6232     INCOMPATIBILITY;