NEWS
author wenzelm
Sat Apr 16 13:48:45 2011 +0200 (2011-04-16)
changeset 42358 b47d41d9f4b5
parent 42290 b1f544c84040
child 42360 da8817d01e7c
permissions -rw-r--r--
Name_Space: proper configuration options long_names, short_names, unique_names instead of former unsynchronized references;
     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: proper configuration options "long_names",
    41 "short_names", "unique_names" instead of former unsynchronized
    42 references.  Minor INCOMPATIBILITY, need to declare options in context
    43 like this:
    44 
    45   declare [[unique_names = false]]
    46 
    47 
    48 *** HOL ***
    49 
    50 * Nitpick:
    51   - Added "need" and "total_consts" options.
    52   - Reintroduced "show_skolems" option by popular demand.
    53   - Renamed attribute: nitpick_def ~> nitpick_unfold.
    54     INCOMPATIBILITY.
    55 
    56 * Sledgehammer:
    57   - sledgehammer available_provers ~> sledgehammer supported_provers
    58     INCOMPATIBILITY.
    59   - Added "monomorphize", "monomorphize_limit", and "type_sys" options.
    60 
    61 * "try":
    62   - Added "simp:", "intro:", and "elim:" options.
    63 
    64 * Quickcheck:
    65   - Added "eval" option to evaluate terms for the found counterexample
    66     (currently only supported by the default (exhaustive) tester)
    67   - Added post-processing of terms to obtain readable counterexamples
    68     (currently only supported by the default (exhaustive) tester)
    69 
    70 * Function package: discontinued option "tailrec".
    71 INCOMPATIBILITY. Use partial_function instead.
    72 
    73 * HOL-Probability:
    74   - Caratheodory's extension lemma is now proved for ring_of_sets.
    75   - Infinite products of probability measures are now available.
    76   - Use extended reals instead of positive extended reals.
    77     INCOMPATIBILITY.
    78 
    79 *** Document preparation ***
    80 
    81 * New term style "isub" as ad-hoc conversion of variables x1, y23 into
    82 subscripted form x\<^isub>1, y\<^isub>2\<^isub>3.
    83 
    84 
    85 *** ML ***
    86 
    87 * Structure Timing provides various operations for timing; supersedes
    88 former start_timing/end_timing etc.
    89 
    90 * Path.print is the official way to show file-system paths to users
    91 (including quotes etc.).
    92 
    93 * Inner syntax: identifiers in parse trees of generic categories
    94 "logic", "aprop", "idt" etc. carry position information (disguised as
    95 type constraints).  Occasional INCOMPATIBILITY with non-compliant
    96 translations that choke on unexpected type constraints.  Positions can
    97 be stripped in ML translations via Syntax.strip_positions /
    98 Syntax.strip_positions_ast, or via the syntax constant
    99 "_strip_positions" within parse trees.  As last resort, positions can
   100 be disabled via the configuration option Syntax.positions, which is
   101 called "syntax_positions" in Isar attribute syntax.
   102 
   103 * Discontinued special status of various ML structures that contribute
   104 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
   105 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
   106 refer directly to Ast.Constant, Lexicon.is_identifier,
   107 Syntax_Trans.mk_binder_tr etc.
   108 
   109 * Typed print translation: discontinued show_sorts argument, which is
   110 already available via context of "advanced" translation.
   111 
   112 
   113 
   114 New in Isabelle2011 (January 2011)
   115 ----------------------------------
   116 
   117 *** General ***
   118 
   119 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
   120 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
   121 useful tooltips and hyperlinks produced from its static analysis.  The
   122 bundled component provides an executable Isabelle tool that can be run
   123 like this:
   124 
   125   Isabelle2011/bin/isabelle jedit
   126 
   127 * Significantly improved Isabelle/Isar implementation manual.
   128 
   129 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
   130 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
   131 while the default heap location within that directory lacks that extra
   132 suffix.  This isolates multiple Isabelle installations from each
   133 other, avoiding problems with old settings in new versions.
   134 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
   135 
   136 * Source files are always encoded as UTF-8, instead of old-fashioned
   137 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   138 the following package declarations:
   139 
   140   \usepackage[utf8]{inputenc}
   141   \usepackage{textcomp}
   142 
   143 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   144 a Unicode character is treated as a single symbol, not a sequence of
   145 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   146 contain symbols without further backslash escapes, Unicode can now be
   147 used here as well.  Recall that Symbol.explode in ML provides a
   148 consistent view on symbols, while raw explode (or String.explode)
   149 merely give a byte-oriented representation.
   150 
   151 * Theory loader: source files are primarily located via the master
   152 directory of each theory node (where the .thy file itself resides).
   153 The global load path is still partially available as legacy feature.
   154 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   155 explicit paths, relatively to the theory.
   156 
   157 * Special treatment of ML file names has been discontinued.
   158 Historically, optional extensions .ML or .sml were added on demand --
   159 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   160 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   161 
   162 * Various options that affect pretty printing etc. are now properly
   163 handled within the context via configuration options, instead of
   164 unsynchronized references or print modes.  There are both ML Config.T
   165 entities and Isar declaration attributes to access these.
   166 
   167   ML (Config.T)                 Isar (attribute)
   168 
   169   eta_contract                  eta_contract
   170   show_brackets                 show_brackets
   171   show_sorts                    show_sorts
   172   show_types                    show_types
   173   show_question_marks           show_question_marks
   174   show_consts                   show_consts
   175   show_abbrevs                  show_abbrevs
   176 
   177   Syntax.ast_trace              syntax_ast_trace
   178   Syntax.ast_stat               syntax_ast_stat
   179   Syntax.ambiguity_level        syntax_ambiguity_level
   180 
   181   Goal_Display.goals_limit      goals_limit
   182   Goal_Display.show_main_goal   show_main_goal
   183 
   184   Method.rule_trace             rule_trace
   185 
   186   Thy_Output.display            thy_output_display
   187   Thy_Output.quotes             thy_output_quotes
   188   Thy_Output.indent             thy_output_indent
   189   Thy_Output.source             thy_output_source
   190   Thy_Output.break              thy_output_break
   191 
   192 Note that corresponding "..._default" references in ML may only be
   193 changed globally at the ROOT session setup, but *not* within a theory.
   194 The option "show_abbrevs" supersedes the former print mode
   195 "no_abbrevs" with inverted meaning.
   196 
   197 * More systematic naming of some configuration options.
   198 INCOMPATIBILITY.
   199 
   200   trace_simp  ~>  simp_trace
   201   debug_simp  ~>  simp_debug
   202 
   203 * Support for real valued configuration options, using simplistic
   204 floating-point notation that coincides with the inner syntax for
   205 float_token.
   206 
   207 * Support for real valued preferences (with approximative PGIP type):
   208 front-ends need to accept "pgint" values in float notation.
   209 INCOMPATIBILITY.
   210 
   211 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   212 DejaVu Sans.
   213 
   214 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   215 
   216 
   217 *** Pure ***
   218 
   219 * Command 'type_synonym' (with single argument) replaces somewhat
   220 outdated 'types', which is still available as legacy feature for some
   221 time.
   222 
   223 * Command 'nonterminal' (with 'and' separated list of arguments)
   224 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   225 
   226 * Command 'notepad' replaces former 'example_proof' for
   227 experimentation in Isar without any result.  INCOMPATIBILITY.
   228 
   229 * Locale interpretation commands 'interpret' and 'sublocale' accept
   230 lists of equations to map definitions in a locale to appropriate
   231 entities in the context of the interpretation.  The 'interpretation'
   232 command already provided this functionality.
   233 
   234 * Diagnostic command 'print_dependencies' prints the locale instances
   235 that would be activated if the specified expression was interpreted in
   236 the current context.  Variant "print_dependencies!" assumes a context
   237 without interpretations.
   238 
   239 * Diagnostic command 'print_interps' prints interpretations in proofs
   240 in addition to interpretations in theories.
   241 
   242 * Discontinued obsolete 'global' and 'local' commands to manipulate
   243 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   244 Sign.root_path and Sign.local_path may be applied directly where this
   245 feature is still required for historical reasons.
   246 
   247 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   248 'definition' instead.
   249 
   250 * The "prems" fact, which refers to the accidental collection of
   251 foundational premises in the context, is now explicitly marked as
   252 legacy feature and will be discontinued soon.  Consider using "assms"
   253 of the head statement or reference facts by explicit names.
   254 
   255 * Document antiquotations @{class} and @{type} print classes and type
   256 constructors.
   257 
   258 * Document antiquotation @{file} checks file/directory entries within
   259 the local file system.
   260 
   261 
   262 *** HOL ***
   263 
   264 * Coercive subtyping: functions can be declared as coercions and type
   265 inference will add them as necessary upon input of a term.  Theory
   266 Complex_Main declares real :: nat => real and real :: int => real as
   267 coercions. A coercion function f is declared like this:
   268 
   269   declare [[coercion f]]
   270 
   271 To lift coercions through type constructors (e.g. from nat => real to
   272 nat list => real list), map functions can be declared, e.g.
   273 
   274   declare [[coercion_map map]]
   275 
   276 Currently coercion inference is activated only in theories including
   277 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   278 the configuration option "coercion_enabled", e.g. it can be enabled in
   279 other theories like this:
   280 
   281   declare [[coercion_enabled]]
   282 
   283 * Command 'partial_function' provides basic support for recursive
   284 function definitions over complete partial orders.  Concrete instances
   285 are provided for i) the option type, ii) tail recursion on arbitrary
   286 types, and iii) the heap monad of Imperative_HOL.  See
   287 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   288 for examples.
   289 
   290 * Function package: f.psimps rules are no longer implicitly declared
   291 as [simp].  INCOMPATIBILITY.
   292 
   293 * Datatype package: theorems generated for executable equality (class
   294 "eq") carry proper names and are treated as default code equations.
   295 
   296 * Inductive package: now offers command 'inductive_simps' to
   297 automatically derive instantiated and simplified equations for
   298 inductive predicates, similar to 'inductive_cases'.
   299 
   300 * Command 'enriched_type' allows to register properties of the
   301 functorial structure of types.
   302 
   303 * Improved infrastructure for term evaluation using code generator
   304 techniques, in particular static evaluation conversions.
   305 
   306 * Code generator: Scala (2.8 or higher) has been added to the target
   307 languages.
   308 
   309 * Code generator: globbing constant expressions "*" and "Theory.*"
   310 have been replaced by the more idiomatic "_" and "Theory._".
   311 INCOMPATIBILITY.
   312 
   313 * Code generator: export_code without explicit file declaration prints
   314 to standard output.  INCOMPATIBILITY.
   315 
   316 * Code generator: do not print function definitions for case
   317 combinators any longer.
   318 
   319 * Code generator: simplification with rules determined with
   320 src/Tools/Code/code_simp.ML and method "code_simp".
   321 
   322 * Code generator for records: more idiomatic representation of record
   323 types.  Warning: records are not covered by ancient SML code
   324 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   325 rep_datatype declaration helps to succeed then:
   326 
   327   record 'a foo = ...
   328   ...
   329   rep_datatype foo_ext ...
   330 
   331 * Records: logical foundation type for records does not carry a
   332 '_type' suffix any longer (obsolete due to authentic syntax).
   333 INCOMPATIBILITY.
   334 
   335 * Quickcheck now by default uses exhaustive testing instead of random
   336 testing.  Random testing can be invoked by "quickcheck [random]",
   337 exhaustive testing by "quickcheck [exhaustive]".
   338 
   339 * Quickcheck instantiates polymorphic types with small finite
   340 datatypes by default. This enables a simple execution mechanism to
   341 handle quantifiers and function equality over the finite datatypes.
   342 
   343 * Quickcheck random generator has been renamed from "code" to
   344 "random".  INCOMPATIBILITY.
   345 
   346 * Quickcheck now has a configurable time limit which is set to 30
   347 seconds by default. This can be changed by adding [timeout = n] to the
   348 quickcheck command. The time limit for Auto Quickcheck is still set
   349 independently.
   350 
   351 * Quickcheck in locales considers interpretations of that locale for
   352 counter example search.
   353 
   354 * Sledgehammer:
   355   - Added "smt" and "remote_smt" provers based on the "smt" proof
   356     method. See the Sledgehammer manual for details ("isabelle doc
   357     sledgehammer").
   358   - Renamed commands:
   359     sledgehammer atp_info ~> sledgehammer running_provers
   360     sledgehammer atp_kill ~> sledgehammer kill_provers
   361     sledgehammer available_atps ~> sledgehammer available_provers
   362     INCOMPATIBILITY.
   363   - Renamed options:
   364     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   365     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   366     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   367     (and "ms" and "min" are no longer supported)
   368     INCOMPATIBILITY.
   369 
   370 * Nitpick:
   371   - Renamed options:
   372     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   373     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   374     INCOMPATIBILITY.
   375   - Added support for partial quotient types.
   376   - Added local versions of the "Nitpick.register_xxx" functions.
   377   - Added "whack" option.
   378   - Allow registration of quotient types as codatatypes.
   379   - Improved "merge_type_vars" option to merge more types.
   380   - Removed unsound "fast_descrs" option.
   381   - Added custom symmetry breaking for datatypes, making it possible to reach
   382     higher cardinalities.
   383   - Prevent the expansion of too large definitions.
   384 
   385 * Proof methods "metis" and "meson" now have configuration options
   386 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   387 to diagnose these tools. E.g.
   388 
   389     using [[metis_trace = true]]
   390 
   391 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   392 manually as command 'solve_direct'.
   393 
   394 * The default SMT solver Z3 must be enabled explicitly (due to
   395 licensing issues) by setting the environment variable
   396 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   397 commercial applications, the SMT solver CVC3 is provided as fall-back;
   398 changing the SMT solver is done via the configuration option
   399 "smt_solver".
   400 
   401 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   402 i.e. "remote_cvc3" and "remote_z3".
   403 
   404 * Added basic SMT support for datatypes, records, and typedefs using
   405 the oracle mode (no proofs).  Direct support of pairs has been dropped
   406 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   407 support for a similar behavior).  Minor INCOMPATIBILITY.
   408 
   409 * Changed SMT configuration options:
   410   - Renamed:
   411     z3_proofs ~> smt_oracle (with inverted meaning)
   412     z3_trace_assms ~> smt_trace_used_facts
   413     INCOMPATIBILITY.
   414   - Added:
   415     smt_verbose
   416     smt_random_seed
   417     smt_datatypes
   418     smt_infer_triggers
   419     smt_monomorph_limit
   420     cvc3_options
   421     remote_cvc3_options
   422     remote_z3_options
   423     yices_options
   424 
   425 * Boogie output files (.b2i files) need to be declared in the theory
   426 header.
   427 
   428 * Simplification procedure "list_to_set_comprehension" rewrites list
   429 comprehensions applied to List.set to set comprehensions.  Occasional
   430 INCOMPATIBILITY, may be deactivated like this:
   431 
   432   declare [[simproc del: list_to_set_comprehension]]
   433 
   434 * Removed old version of primrec package.  INCOMPATIBILITY.
   435 
   436 * Removed simplifier congruence rule of "prod_case", as has for long
   437 been the case with "split".  INCOMPATIBILITY.
   438 
   439 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   440 
   441 * Removed [split_format ... and ... and ...] version of
   442 [split_format].  Potential INCOMPATIBILITY.
   443 
   444 * Predicate "sorted" now defined inductively, with nice induction
   445 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   446 
   447 * Constant "contents" renamed to "the_elem", to free the generic name
   448 contents for other uses.  INCOMPATIBILITY.
   449 
   450 * Renamed class eq and constant eq (for code generation) to class
   451 equal and constant equal, plus renaming of related facts and various
   452 tuning.  INCOMPATIBILITY.
   453 
   454 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   455 
   456 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   457 INCOMPATIBILITY.
   458 
   459 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   460 avoid confusion with finite sets.  INCOMPATIBILITY.
   461 
   462 * Abandoned locales equiv, congruent and congruent2 for equivalence
   463 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   464 for congruent(2)).
   465 
   466 * Some previously unqualified names have been qualified:
   467 
   468   types
   469     bool ~> HOL.bool
   470     nat ~> Nat.nat
   471 
   472   constants
   473     Trueprop ~> HOL.Trueprop
   474     True ~> HOL.True
   475     False ~> HOL.False
   476     op & ~> HOL.conj
   477     op | ~> HOL.disj
   478     op --> ~> HOL.implies
   479     op = ~> HOL.eq
   480     Not ~> HOL.Not
   481     The ~> HOL.The
   482     All ~> HOL.All
   483     Ex ~> HOL.Ex
   484     Ex1 ~> HOL.Ex1
   485     Let ~> HOL.Let
   486     If ~> HOL.If
   487     Ball ~> Set.Ball
   488     Bex ~> Set.Bex
   489     Suc ~> Nat.Suc
   490     Pair ~> Product_Type.Pair
   491     fst ~> Product_Type.fst
   492     snd ~> Product_Type.snd
   493     curry ~> Product_Type.curry
   494     op : ~> Set.member
   495     Collect ~> Set.Collect
   496 
   497 INCOMPATIBILITY.
   498 
   499 * More canonical naming convention for some fundamental definitions:
   500 
   501     bot_bool_eq ~> bot_bool_def
   502     top_bool_eq ~> top_bool_def
   503     inf_bool_eq ~> inf_bool_def
   504     sup_bool_eq ~> sup_bool_def
   505     bot_fun_eq  ~> bot_fun_def
   506     top_fun_eq  ~> top_fun_def
   507     inf_fun_eq  ~> inf_fun_def
   508     sup_fun_eq  ~> sup_fun_def
   509 
   510 INCOMPATIBILITY.
   511 
   512 * More stylized fact names:
   513 
   514   expand_fun_eq ~> fun_eq_iff
   515   expand_set_eq ~> set_eq_iff
   516   set_ext       ~> set_eqI
   517   nat_number    ~> eval_nat_numeral
   518 
   519 INCOMPATIBILITY.
   520 
   521 * Refactoring of code-generation specific operations in theory List:
   522 
   523   constants
   524     null ~> List.null
   525 
   526   facts
   527     mem_iff ~> member_def
   528     null_empty ~> null_def
   529 
   530 INCOMPATIBILITY.  Note that these were not supposed to be used
   531 regularly unless for striking reasons; their main purpose was code
   532 generation.
   533 
   534 Various operations from the Haskell prelude are used for generating
   535 Haskell code.
   536 
   537 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   538 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   539 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   540 
   541 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   542 "*" and "+" respectively.  INCOMPATIBILITY.
   543 
   544 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   545 "Sum_Type.Plus" instead.
   546 
   547 * Constant "split" has been merged with constant "prod_case"; names of
   548 ML functions, facts etc. involving split have been retained so far,
   549 though.  INCOMPATIBILITY.
   550 
   551 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   552 instead.  INCOMPATIBILITY.
   553 
   554 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   555 INCOMPATIBILITY.
   556 
   557 * Former theory Library/Enum is now part of the HOL-Main image.
   558 INCOMPATIBILITY: all constants of the Enum theory now have to be
   559 referred to by its qualified name.
   560 
   561   enum    ~>  Enum.enum
   562   nlists  ~>  Enum.nlists
   563   product ~>  Enum.product
   564 
   565 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   566 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   567 INCOMPATIBILITY.
   568 
   569 * Theory Library/SetsAndFunctions has been split into
   570 Library/Function_Algebras and Library/Set_Algebras; canonical names
   571 for instance definitions for functions; various improvements.
   572 INCOMPATIBILITY.
   573 
   574 * Theory Library/Multiset provides stable quicksort implementation of
   575 sort_key.
   576 
   577 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   578 INCOMPATIBILITY.
   579 
   580 * Session Multivariate_Analysis: introduced a type class for euclidean
   581 space.  Most theorems are now stated in terms of euclidean spaces
   582 instead of finite cartesian products.
   583 
   584   types
   585     real ^ 'n ~>  'a::real_vector
   586               ~>  'a::euclidean_space
   587               ~>  'a::ordered_euclidean_space
   588         (depends on your needs)
   589 
   590   constants
   591      _ $ _        ~> _ $$ _
   592      \<chi> x. _  ~> \<chi>\<chi> x. _
   593      CARD('n)     ~> DIM('a)
   594 
   595 Also note that the indices are now natural numbers and not from some
   596 finite type. Finite cartesian products of euclidean spaces, products
   597 of euclidean spaces the real and complex numbers are instantiated to
   598 be euclidean_spaces.  INCOMPATIBILITY.
   599 
   600 * Session Probability: introduced pextreal as positive extended real
   601 numbers.  Use pextreal as value for measures.  Introduce the
   602 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   603 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   604 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   605 
   606 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   607 INCOMPATIBILITY.
   608 
   609 * Session SPARK (with image HOL-SPARK) provides commands to load and
   610 prove verification conditions generated by the SPARK Ada program
   611 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   612 
   613 
   614 *** HOL-Algebra ***
   615 
   616 * Theorems for additive ring operations (locale abelian_monoid and
   617 descendants) are generated by interpretation from their multiplicative
   618 counterparts.  Names (in particular theorem names) have the mandatory
   619 qualifier 'add'.  Previous theorem names are redeclared for
   620 compatibility.
   621 
   622 * Structure "int_ring" is now an abbreviation (previously a
   623 definition).  This fits more natural with advanced interpretations.
   624 
   625 
   626 *** HOLCF ***
   627 
   628 * The domain package now runs in definitional mode by default: The
   629 former command 'new_domain' is now called 'domain'.  To use the domain
   630 package in its original axiomatic mode, use 'domain (unsafe)'.
   631 INCOMPATIBILITY.
   632 
   633 * The new class "domain" is now the default sort.  Class "predomain"
   634 is an unpointed version of "domain". Theories can be updated by
   635 replacing sort annotations as shown below.  INCOMPATIBILITY.
   636 
   637   'a::type ~> 'a::countable
   638   'a::cpo  ~> 'a::predomain
   639   'a::pcpo ~> 'a::domain
   640 
   641 * The old type class "rep" has been superseded by class "domain".
   642 Accordingly, users of the definitional package must remove any
   643 "default_sort rep" declarations.  INCOMPATIBILITY.
   644 
   645 * The domain package (definitional mode) now supports unpointed
   646 predomain argument types, as long as they are marked 'lazy'. (Strict
   647 arguments must be in class "domain".) For example, the following
   648 domain definition now works:
   649 
   650   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   651 
   652 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   653 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   654 'a option, and 'a list.  Additionally, it configures fixrec and the
   655 domain package to work with these types.  For example:
   656 
   657   fixrec isInl :: "('a + 'b) u -> tr"
   658     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   659 
   660   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   661 
   662 * The "(permissive)" option of fixrec has been replaced with a
   663 per-equation "(unchecked)" option. See
   664 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
   665 
   666 * The "bifinite" class no longer fixes a constant "approx"; the class
   667 now just asserts that such a function exists.  INCOMPATIBILITY.
   668 
   669 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
   670 defines an embedding of type 'a defl into udom by default; instances
   671 of "bifinite" and "domain" classes are available in
   672 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
   673 
   674 * The syntax "REP('a)" has been replaced with "DEFL('a)".
   675 
   676 * The predicate "directed" has been removed.  INCOMPATIBILITY.
   677 
   678 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
   679 
   680 * The function "cprod_map" has been renamed to "prod_map".
   681 INCOMPATIBILITY.
   682 
   683 * The monadic bind operator on each powerdomain has new binder syntax
   684 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
   685 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
   686 
   687 * The infix syntax for binary union on each powerdomain has changed
   688 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
   689 syntax.  INCOMPATIBILITY.
   690 
   691 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
   692 still supported as an input translation.
   693 
   694 * Renamed some theorems (the original names are also still available).
   695 
   696   expand_fun_below   ~> fun_below_iff
   697   below_fun_ext      ~> fun_belowI
   698   expand_cfun_eq     ~> cfun_eq_iff
   699   ext_cfun           ~> cfun_eqI
   700   expand_cfun_below  ~> cfun_below_iff
   701   below_cfun_ext     ~> cfun_belowI
   702   cont2cont_Rep_CFun ~> cont2cont_APP
   703 
   704 * The Abs and Rep functions for various types have changed names.
   705 Related theorem names have also changed to match. INCOMPATIBILITY.
   706 
   707   Rep_CFun  ~> Rep_cfun
   708   Abs_CFun  ~> Abs_cfun
   709   Rep_Sprod ~> Rep_sprod
   710   Abs_Sprod ~> Abs_sprod
   711   Rep_Ssum  ~> Rep_ssum
   712   Abs_Ssum  ~> Abs_ssum
   713 
   714 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   715 been renamed to *_bottom_iff.  INCOMPATIBILITY.
   716 
   717 * Various changes to bisimulation/coinduction with domain package:
   718 
   719   - Definitions of "bisim" constants no longer mention definedness.
   720   - With mutual recursion, "bisim" predicate is now curried.
   721   - With mutual recursion, each type gets a separate coind theorem.
   722   - Variable names in bisim_def and coinduct rules have changed.
   723 
   724 INCOMPATIBILITY.
   725 
   726 * Case combinators generated by the domain package for type "foo" are
   727 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
   728 
   729 * Several theorems have been renamed to more accurately reflect the
   730 names of constants and types involved.  INCOMPATIBILITY.
   731 
   732   thelub_const    ~> lub_const
   733   lub_const       ~> is_lub_const
   734   thelubI         ~> lub_eqI
   735   is_lub_lub      ~> is_lubD2
   736   lubI            ~> is_lub_lub
   737   unique_lub      ~> is_lub_unique
   738   is_ub_lub       ~> is_lub_rangeD1
   739   lub_bin_chain   ~> is_lub_bin_chain
   740   lub_fun         ~> is_lub_fun
   741   thelub_fun      ~> lub_fun
   742   thelub_cfun     ~> lub_cfun
   743   thelub_Pair     ~> lub_Pair
   744   lub_cprod       ~> is_lub_prod
   745   thelub_cprod    ~> lub_prod
   746   minimal_cprod   ~> minimal_prod
   747   inst_cprod_pcpo ~> inst_prod_pcpo
   748   UU_I            ~> bottomI
   749   compact_UU      ~> compact_bottom
   750   deflation_UU    ~> deflation_bottom
   751   finite_deflation_UU ~> finite_deflation_bottom
   752 
   753 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
   754 
   755   sq_ord_less_eq_trans ~> below_eq_trans
   756   sq_ord_eq_less_trans ~> eq_below_trans
   757   refl_less            ~> below_refl
   758   trans_less           ~> below_trans
   759   antisym_less         ~> below_antisym
   760   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
   761   box_less             ~> box_below
   762   rev_trans_less       ~> rev_below_trans
   763   not_less2not_eq      ~> not_below2not_eq
   764   less_UU_iff          ~> below_UU_iff
   765   flat_less_iff        ~> flat_below_iff
   766   adm_less             ~> adm_below
   767   adm_not_less         ~> adm_not_below
   768   adm_compact_not_less ~> adm_compact_not_below
   769   less_fun_def         ~> below_fun_def
   770   expand_fun_less      ~> fun_below_iff
   771   less_fun_ext         ~> fun_belowI
   772   less_discr_def       ~> below_discr_def
   773   discr_less_eq        ~> discr_below_eq
   774   less_unit_def        ~> below_unit_def
   775   less_cprod_def       ~> below_prod_def
   776   prod_lessI           ~> prod_belowI
   777   Pair_less_iff        ~> Pair_below_iff
   778   fst_less_iff         ~> fst_below_iff
   779   snd_less_iff         ~> snd_below_iff
   780   expand_cfun_less     ~> cfun_below_iff
   781   less_cfun_ext        ~> cfun_belowI
   782   injection_less       ~> injection_below
   783   less_up_def          ~> below_up_def
   784   not_Iup_less         ~> not_Iup_below
   785   Iup_less             ~> Iup_below
   786   up_less              ~> up_below
   787   Def_inject_less_eq   ~> Def_below_Def
   788   Def_less_is_eq       ~> Def_below_iff
   789   spair_less_iff       ~> spair_below_iff
   790   less_sprod           ~> below_sprod
   791   spair_less           ~> spair_below
   792   sfst_less_iff        ~> sfst_below_iff
   793   ssnd_less_iff        ~> ssnd_below_iff
   794   fix_least_less       ~> fix_least_below
   795   dist_less_one        ~> dist_below_one
   796   less_ONE             ~> below_ONE
   797   ONE_less_iff         ~> ONE_below_iff
   798   less_sinlD           ~> below_sinlD
   799   less_sinrD           ~> below_sinrD
   800 
   801 
   802 *** FOL and ZF ***
   803 
   804 * All constant names are now qualified internally and use proper
   805 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
   806 
   807 
   808 *** ML ***
   809 
   810 * Antiquotation @{assert} inlines a function bool -> unit that raises
   811 Fail if the argument is false.  Due to inlining the source position of
   812 failed assertions is included in the error output.
   813 
   814 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
   815 text is in practice always evaluated with a stable theory checkpoint.
   816 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
   817 
   818 * Antiquotation @{theory A} refers to theory A from the ancestry of
   819 the current context, not any accidental theory loader state as before.
   820 Potential INCOMPATIBILITY, subtle change in semantics.
   821 
   822 * Syntax.pretty_priority (default 0) configures the required priority
   823 of pretty-printed output and thus affects insertion of parentheses.
   824 
   825 * Syntax.default_root (default "any") configures the inner syntax
   826 category (nonterminal symbol) for parsing of terms.
   827 
   828 * Former exception Library.UnequalLengths now coincides with
   829 ListPair.UnequalLengths.
   830 
   831 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
   832 main functionality is provided by structure Simplifier.
   833 
   834 * Renamed raw "explode" function to "raw_explode" to emphasize its
   835 meaning.  Note that internally to Isabelle, Symbol.explode is used in
   836 almost all situations.
   837 
   838 * Discontinued obsolete function sys_error and exception SYS_ERROR.
   839 See implementation manual for further details on exceptions in
   840 Isabelle/ML.
   841 
   842 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   843 meaning.
   844 
   845 * Renamed structure PureThy to Pure_Thy and moved most of its
   846 operations to structure Global_Theory, to emphasize that this is
   847 rarely-used global-only stuff.
   848 
   849 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
   850 instead (or tracing for high-volume output).
   851 
   852 * Configuration option show_question_marks only affects regular pretty
   853 printing of types and terms, not raw Term.string_of_vname.
   854 
   855 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
   856 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
   857 @{thms} for most purposes.
   858 
   859 * ML structure Unsynchronized is never opened, not even in Isar
   860 interaction mode as before.  Old Unsynchronized.set etc. have been
   861 discontinued -- use plain := instead.  This should be *rare* anyway,
   862 since modern tools always work via official context data, notably
   863 configuration options.
   864 
   865 * Parallel and asynchronous execution requires special care concerning
   866 interrupts.  Structure Exn provides some convenience functions that
   867 avoid working directly with raw Interrupt.  User code must not absorb
   868 interrupts -- intermediate handling (for cleanup etc.) needs to be
   869 followed by re-raising of the original exception.  Another common
   870 source of mistakes are "handle _" patterns, which make the meaning of
   871 the program subject to physical effects of the environment.
   872 
   873 
   874 
   875 New in Isabelle2009-2 (June 2010)
   876 ---------------------------------
   877 
   878 *** General ***
   879 
   880 * Authentic syntax for *all* logical entities (type classes, type
   881 constructors, term constants): provides simple and robust
   882 correspondence between formal entities and concrete syntax.  Within
   883 the parse tree / AST representations, "constants" are decorated by
   884 their category (class, type, const) and spelled out explicitly with
   885 their full internal name.
   886 
   887 Substantial INCOMPATIBILITY concerning low-level syntax declarations
   888 and translations (translation rules and translation functions in ML).
   889 Some hints on upgrading:
   890 
   891   - Many existing uses of 'syntax' and 'translations' can be replaced
   892     by more modern 'type_notation', 'notation' and 'abbreviation',
   893     which are independent of this issue.
   894 
   895   - 'translations' require markup within the AST; the term syntax
   896     provides the following special forms:
   897 
   898       CONST c   -- produces syntax version of constant c from context
   899       XCONST c  -- literally c, checked as constant from context
   900       c         -- literally c, if declared by 'syntax'
   901 
   902     Plain identifiers are treated as AST variables -- occasionally the
   903     system indicates accidental variables via the error "rhs contains
   904     extra variables".
   905 
   906     Type classes and type constructors are marked according to their
   907     concrete syntax.  Some old translations rules need to be written
   908     for the "type" category, using type constructor application
   909     instead of pseudo-term application of the default category
   910     "logic".
   911 
   912   - 'parse_translation' etc. in ML may use the following
   913     antiquotations:
   914 
   915       @{class_syntax c}   -- type class c within parse tree / AST
   916       @{term_syntax c}    -- type constructor c within parse tree / AST
   917       @{const_syntax c}   -- ML version of "CONST c" above
   918       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
   919 
   920   - Literal types within 'typed_print_translations', i.e. those *not*
   921     represented as pseudo-terms are represented verbatim.  Use @{class
   922     c} or @{type_name c} here instead of the above syntax
   923     antiquotations.
   924 
   925 Note that old non-authentic syntax was based on unqualified base
   926 names, so all of the above "constant" names would coincide.  Recall
   927 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
   928 diagnose syntax problems.
   929 
   930 * Type constructors admit general mixfix syntax, not just infix.
   931 
   932 * Concrete syntax may be attached to local entities without a proof
   933 body, too.  This works via regular mixfix annotations for 'fix',
   934 'def', 'obtain' etc. or via the explicit 'write' command, which is
   935 similar to the 'notation' command in theory specifications.
   936 
   937 * Discontinued unnamed infix syntax (legacy feature for many years) --
   938 need to specify constant name and syntax separately.  Internal ML
   939 datatype constructors have been renamed from InfixName to Infix etc.
   940 Minor INCOMPATIBILITY.
   941 
   942 * Schematic theorem statements need to be explicitly markup as such,
   943 via commands 'schematic_lemma', 'schematic_theorem',
   944 'schematic_corollary'.  Thus the relevance of the proof is made
   945 syntactically clear, which impacts performance in a parallel or
   946 asynchronous interactive environment.  Minor INCOMPATIBILITY.
   947 
   948 * Use of cumulative prems via "!" in some proof methods has been
   949 discontinued (old legacy feature).
   950 
   951 * References 'trace_simp' and 'debug_simp' have been replaced by
   952 configuration options stored in the context. Enabling tracing (the
   953 case of debugging is similar) in proofs works via
   954 
   955   using [[trace_simp = true]]
   956 
   957 Tracing is then active for all invocations of the simplifier in
   958 subsequent goal refinement steps. Tracing may also still be enabled or
   959 disabled via the ProofGeneral settings menu.
   960 
   961 * Separate commands 'hide_class', 'hide_type', 'hide_const',
   962 'hide_fact' replace the former 'hide' KIND command.  Minor
   963 INCOMPATIBILITY.
   964 
   965 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
   966 more efficient than combinations with -q1 or -q2.
   967 
   968 
   969 *** Pure ***
   970 
   971 * Proofterms record type-class reasoning explicitly, using the
   972 "unconstrain" operation internally.  This eliminates all sort
   973 constraints from a theorem and proof, introducing explicit
   974 OFCLASS-premises.  On the proof term level, this operation is
   975 automatically applied at theorem boundaries, such that closed proofs
   976 are always free of sort constraints.  INCOMPATIBILITY for tools that
   977 inspect proof terms.
   978 
   979 * Local theory specifications may depend on extra type variables that
   980 are not present in the result type -- arguments TYPE('a) :: 'a itself
   981 are added internally.  For example:
   982 
   983   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
   984 
   985 * Predicates of locales introduced by classes carry a mandatory
   986 "class" prefix.  INCOMPATIBILITY.
   987 
   988 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
   989 
   990 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
   991 'class' instead.
   992 
   993 * Command 'code_reflect' allows to incorporate generated ML code into
   994 runtime environment; replaces immature code_datatype antiquotation.
   995 INCOMPATIBILITY.
   996 
   997 * Code generator: simple concept for abstract datatypes obeying
   998 invariants.
   999 
  1000 * Code generator: details of internal data cache have no impact on the
  1001 user space functionality any longer.
  1002 
  1003 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1004 subgoals.  This is more appropriate for interpretations with 'where'.
  1005 INCOMPATIBILITY.
  1006 
  1007 * Command 'example_proof' opens an empty proof body.  This allows to
  1008 experiment with Isar, without producing any persistent result.
  1009 
  1010 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1011 within a local theory context, with explicit checking of the
  1012 constructors involved (in contrast to the raw 'syntax' versions).
  1013 
  1014 * Commands 'types' and 'typedecl' now work within a local theory
  1015 context -- without introducing dependencies on parameters or
  1016 assumptions, which is not possible in Isabelle/Pure.
  1017 
  1018 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1019 within a local theory context.  Minor INCOMPATIBILITY.
  1020 
  1021 
  1022 *** HOL ***
  1023 
  1024 * Command 'typedef' now works within a local theory context -- without
  1025 introducing dependencies on parameters or assumptions, which is not
  1026 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1027 contain multiple interpretations of local typedefs (with different
  1028 non-emptiness proofs), even in a global theory context.
  1029 
  1030 * New package for quotient types.  Commands 'quotient_type' and
  1031 'quotient_definition' may be used for defining types and constants by
  1032 quotient constructions.  An example is the type of integers created by
  1033 quotienting pairs of natural numbers:
  1034 
  1035   fun
  1036     intrel :: "(nat * nat) => (nat * nat) => bool"
  1037   where
  1038     "intrel (x, y) (u, v) = (x + v = u + y)"
  1039 
  1040   quotient_type int = "nat * nat" / intrel
  1041     by (auto simp add: equivp_def expand_fun_eq)
  1042 
  1043   quotient_definition
  1044     "0::int" is "(0::nat, 0::nat)"
  1045 
  1046 The method "lifting" can be used to lift of theorems from the
  1047 underlying "raw" type to the quotient type.  The example
  1048 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1049 construction and provides a reasoning infrastructure for finite sets.
  1050 
  1051 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1052 clash with new theory Quotient in Main HOL.
  1053 
  1054 * Moved the SMT binding into the main HOL session, eliminating
  1055 separate HOL-SMT session.
  1056 
  1057 * List membership infix mem operation is only an input abbreviation.
  1058 INCOMPATIBILITY.
  1059 
  1060 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1061 for future developements; former Library/Word.thy is still present in
  1062 the AFP entry RSAPPS.
  1063 
  1064 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1065 longer shadowed.  INCOMPATIBILITY.
  1066 
  1067 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1068 INCOMPATIBILITY.
  1069 
  1070 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1071 INCOMPATIBILITY.
  1072 
  1073 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1074 instead.  INCOMPATIBILITY.
  1075 
  1076 * Dropped several real-specific versions of lemmas about floor and
  1077 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1078 instead.  INCOMPATIBILITY.
  1079 
  1080   floor_number_of_eq         ~> floor_number_of
  1081   le_floor_eq_number_of      ~> number_of_le_floor
  1082   le_floor_eq_zero           ~> zero_le_floor
  1083   le_floor_eq_one            ~> one_le_floor
  1084   floor_less_eq_number_of    ~> floor_less_number_of
  1085   floor_less_eq_zero         ~> floor_less_zero
  1086   floor_less_eq_one          ~> floor_less_one
  1087   less_floor_eq_number_of    ~> number_of_less_floor
  1088   less_floor_eq_zero         ~> zero_less_floor
  1089   less_floor_eq_one          ~> one_less_floor
  1090   floor_le_eq_number_of      ~> floor_le_number_of
  1091   floor_le_eq_zero           ~> floor_le_zero
  1092   floor_le_eq_one            ~> floor_le_one
  1093   floor_subtract_number_of   ~> floor_diff_number_of
  1094   floor_subtract_one         ~> floor_diff_one
  1095   ceiling_number_of_eq       ~> ceiling_number_of
  1096   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1097   ceiling_le_zero_eq         ~> ceiling_le_zero
  1098   ceiling_le_eq_one          ~> ceiling_le_one
  1099   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1100   less_ceiling_eq_zero       ~> zero_less_ceiling
  1101   less_ceiling_eq_one        ~> one_less_ceiling
  1102   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1103   ceiling_less_eq_zero       ~> ceiling_less_zero
  1104   ceiling_less_eq_one        ~> ceiling_less_one
  1105   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1106   le_ceiling_eq_zero         ~> zero_le_ceiling
  1107   le_ceiling_eq_one          ~> one_le_ceiling
  1108   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1109   ceiling_subtract_one       ~> ceiling_diff_one
  1110 
  1111 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1112 application of the various fold combinators on finite sets.
  1113 
  1114 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1115 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1116 implementation.  INCOMPATIBILTY.
  1117 
  1118 * Theory Library/Coinductive_List has been removed -- superseded by
  1119 AFP/thys/Coinductive.
  1120 
  1121 * Theory PReal, including the type "preal" and related operations, has
  1122 been removed.  INCOMPATIBILITY.
  1123 
  1124 * Real: new development using Cauchy Sequences.
  1125 
  1126 * Split off theory "Big_Operators" containing setsum, setprod,
  1127 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1128 
  1129 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1130 "Int" etc.  INCOMPATIBILITY.
  1131 
  1132 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1133 
  1134 * New set of rules "ac_simps" provides combined assoc / commute
  1135 rewrites for all interpretations of the appropriate generic locales.
  1136 
  1137 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1138 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1139 appropriate and more consistent names suitable for name prefixes
  1140 within the HOL theories.  INCOMPATIBILITY.
  1141 
  1142 * Some generic constants have been put to appropriate theories:
  1143   - less_eq, less: Orderings
  1144   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1145   - inverse, divide: Rings
  1146 INCOMPATIBILITY.
  1147 
  1148 * More consistent naming of type classes involving orderings (and
  1149 lattices):
  1150 
  1151     lower_semilattice                   ~> semilattice_inf
  1152     upper_semilattice                   ~> semilattice_sup
  1153 
  1154     dense_linear_order                  ~> dense_linorder
  1155 
  1156     pordered_ab_group_add               ~> ordered_ab_group_add
  1157     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1158     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1159     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1160     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1161     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1162     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1163     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1164     pordered_comm_ring                  ~> ordered_comm_ring
  1165     pordered_comm_semiring              ~> ordered_comm_semiring
  1166     pordered_ring                       ~> ordered_ring
  1167     pordered_ring_abs                   ~> ordered_ring_abs
  1168     pordered_semiring                   ~> ordered_semiring
  1169 
  1170     ordered_ab_group_add                ~> linordered_ab_group_add
  1171     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1172     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1173     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1174     ordered_field                       ~> linordered_field
  1175     ordered_field_no_lb                 ~> linordered_field_no_lb
  1176     ordered_field_no_ub                 ~> linordered_field_no_ub
  1177     ordered_field_dense_linear_order    ~> dense_linordered_field
  1178     ordered_idom                        ~> linordered_idom
  1179     ordered_ring                        ~> linordered_ring
  1180     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1181     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1182     ordered_ring_strict                 ~> linordered_ring_strict
  1183     ordered_semidom                     ~> linordered_semidom
  1184     ordered_semiring                    ~> linordered_semiring
  1185     ordered_semiring_1                  ~> linordered_semiring_1
  1186     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1187     ordered_semiring_strict             ~> linordered_semiring_strict
  1188 
  1189   The following slightly odd type classes have been moved to a
  1190   separate theory Library/Lattice_Algebras:
  1191 
  1192     lordered_ab_group_add               ~> lattice_ab_group_add
  1193     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1194     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1195     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1196     lordered_ring                       ~> lattice_ring
  1197 
  1198 INCOMPATIBILITY.
  1199 
  1200 * Refined field classes:
  1201   - classes division_ring_inverse_zero, field_inverse_zero,
  1202     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1203     subsumes former division_by_zero class;
  1204   - numerous lemmas have been ported from field to division_ring.
  1205 INCOMPATIBILITY.
  1206 
  1207 * Refined algebra theorem collections:
  1208   - dropped theorem group group_simps, use algebra_simps instead;
  1209   - dropped theorem group ring_simps, use field_simps instead;
  1210   - proper theorem collection field_simps subsumes former theorem
  1211     groups field_eq_simps and field_simps;
  1212   - dropped lemma eq_minus_self_iff which is a duplicate for
  1213     equal_neg_zero.
  1214 INCOMPATIBILITY.
  1215 
  1216 * Theory Finite_Set and List: some lemmas have been generalized from
  1217 sets to lattices:
  1218 
  1219   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1220   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1221   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1222   union_Union_fold_union        ~> sup_Sup_fold_sup
  1223   Inter_fold_inter              ~> Inf_fold_inf
  1224   Union_fold_union              ~> Sup_fold_sup
  1225   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1226   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1227   INTER_fold_inter              ~> INFI_fold_inf
  1228   UNION_fold_union              ~> SUPR_fold_sup
  1229 
  1230 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1231 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1232 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1233 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1234 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1235 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1236 
  1237 * Reorganized theory Multiset: swapped notation of pointwise and
  1238 multiset order:
  1239 
  1240   - pointwise ordering is instance of class order with standard syntax
  1241     <= and <;
  1242   - multiset ordering has syntax <=# and <#; partial order properties
  1243     are provided by means of interpretation with prefix
  1244     multiset_order;
  1245   - less duplication, less historical organization of sections,
  1246     conversion from associations lists to multisets, rudimentary code
  1247     generation;
  1248   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1249     if needed.
  1250 
  1251 Renamed:
  1252 
  1253   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1254   multi_count_ext  ~>  multiset_ext
  1255   diff_union_inverse2  ~>  diff_union_cancelR
  1256 
  1257 INCOMPATIBILITY.
  1258 
  1259 * Theory Permutation: replaced local "remove" by List.remove1.
  1260 
  1261 * Code generation: ML and OCaml code is decorated with signatures.
  1262 
  1263 * Theory List: added transpose.
  1264 
  1265 * Library/Nat_Bijection.thy is a collection of bijective functions
  1266 between nat and other types, which supersedes the older libraries
  1267 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1268 
  1269   Constants:
  1270   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1271   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1272   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1273   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1274   Countable.pair_encode           ~> prod_encode
  1275   NatIso.prod2nat                 ~> prod_encode
  1276   NatIso.nat2prod                 ~> prod_decode
  1277   NatIso.sum2nat                  ~> sum_encode
  1278   NatIso.nat2sum                  ~> sum_decode
  1279   NatIso.list2nat                 ~> list_encode
  1280   NatIso.nat2list                 ~> list_decode
  1281   NatIso.set2nat                  ~> set_encode
  1282   NatIso.nat2set                  ~> set_decode
  1283 
  1284   Lemmas:
  1285   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1286   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1287   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1288   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1289   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1290   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1291   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1292   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1293   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1294   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1295   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1296   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1297   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1298 
  1299 * Sledgehammer:
  1300   - Renamed ATP commands:
  1301     atp_info     ~> sledgehammer running_atps
  1302     atp_kill     ~> sledgehammer kill_atps
  1303     atp_messages ~> sledgehammer messages
  1304     atp_minimize ~> sledgehammer minimize
  1305     print_atps   ~> sledgehammer available_atps
  1306     INCOMPATIBILITY.
  1307   - Added user's manual ("isabelle doc sledgehammer").
  1308   - Added option syntax and "sledgehammer_params" to customize
  1309     Sledgehammer's behavior.  See the manual for details.
  1310   - Modified the Isar proof reconstruction code so that it produces
  1311     direct proofs rather than proofs by contradiction.  (This feature
  1312     is still experimental.)
  1313   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1314     full-typed mode.
  1315   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1316 
  1317 * Nitpick:
  1318   - Added and implemented "binary_ints" and "bits" options.
  1319   - Added "std" option and implemented support for nonstandard models.
  1320   - Added and implemented "finitize" option to improve the precision
  1321     of infinite datatypes based on a monotonicity analysis.
  1322   - Added support for quotient types.
  1323   - Added support for "specification" and "ax_specification"
  1324     constructs.
  1325   - Added support for local definitions (for "function" and
  1326     "termination" proofs).
  1327   - Added support for term postprocessors.
  1328   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1329   - Improved efficiency of "destroy_constrs" optimization.
  1330   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1331     record getters.
  1332   - Fixed soundness bug related to higher-order constructors.
  1333   - Fixed soundness bug when "full_descrs" is enabled.
  1334   - Improved precision of set constructs.
  1335   - Added "atoms" option.
  1336   - Added cache to speed up repeated Kodkod invocations on the same
  1337     problems.
  1338   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1339     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1340     "SAT4J_Light".  INCOMPATIBILITY.
  1341   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1342     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1343   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1344 
  1345 * Method "induct" now takes instantiations of the form t, where t is not
  1346   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1347   If this is not intended, t has to be enclosed in parentheses.
  1348   By default, the equalities generated by definitional instantiations
  1349   are pre-simplified, which may cause parameters of inductive cases
  1350   to disappear, or may even delete some of the inductive cases.
  1351   Use "induct (no_simp)" instead of "induct" to restore the old
  1352   behaviour. The (no_simp) option is also understood by the "cases"
  1353   and "nominal_induct" methods, which now perform pre-simplification, too.
  1354   INCOMPATIBILITY.
  1355 
  1356 
  1357 *** HOLCF ***
  1358 
  1359 * Variable names in lemmas generated by the domain package have
  1360 changed; the naming scheme is now consistent with the HOL datatype
  1361 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1362 
  1363 * The domain package no longer defines the function "foo_copy" for
  1364 recursive domain "foo".  The reach lemma is now stated directly in
  1365 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1366 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1367 
  1368 * Most definedness lemmas generated by the domain package (previously
  1369 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1370 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1371 Proofs that used definedness lemmas as intro rules may break,
  1372 potential INCOMPATIBILITY.
  1373 
  1374 * Induction and casedist rules generated by the domain package now
  1375 declare proper case_names (one called "bottom", and one named for each
  1376 constructor).  INCOMPATIBILITY.
  1377 
  1378 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1379 rules are generated for each domain, INCOMPATIBILITY.
  1380 
  1381   foo_bar.reach       ~> foo.reach  bar.reach
  1382   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1383 
  1384 * Some lemmas generated by the domain package have been renamed for
  1385 consistency with the datatype package, INCOMPATIBILITY.
  1386 
  1387   foo.ind        ~> foo.induct
  1388   foo.finite_ind ~> foo.finite_induct
  1389   foo.coind      ~> foo.coinduct
  1390   foo.casedist   ~> foo.exhaust
  1391   foo.exhaust    ~> foo.nchotomy
  1392 
  1393 * For consistency with other definition packages, the fixrec package
  1394 now generates qualified theorem names, INCOMPATIBILITY.
  1395 
  1396   foo_simps  ~> foo.simps
  1397   foo_unfold ~> foo.unfold
  1398   foo_induct ~> foo.induct
  1399 
  1400 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1401 method and internal fixrec proofs now use the default simpset instead.
  1402 INCOMPATIBILITY.
  1403 
  1404 * The "contlub" predicate has been removed.  Proof scripts should use
  1405 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1406 
  1407 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1408 
  1409 * The constants cpair, cfst, and csnd have been removed in favor of
  1410 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1411 
  1412 
  1413 *** ML ***
  1414 
  1415 * Antiquotations for basic formal entities:
  1416 
  1417     @{class NAME}         -- type class
  1418     @{class_syntax NAME}  -- syntax representation of the above
  1419 
  1420     @{type_name NAME}     -- logical type
  1421     @{type_abbrev NAME}   -- type abbreviation
  1422     @{nonterminal NAME}   -- type of concrete syntactic category
  1423     @{type_syntax NAME}   -- syntax representation of any of the above
  1424 
  1425     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1426     @{const_abbrev NAME}  -- abbreviated constant
  1427     @{const_syntax NAME}  -- syntax representation of any of the above
  1428 
  1429 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1430 syntax constant (cf. 'syntax' command).
  1431 
  1432 * Antiquotation @{make_string} inlines a function to print arbitrary
  1433 values similar to the ML toplevel.  The result is compiler dependent
  1434 and may fall back on "?" in certain situations.
  1435 
  1436 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1437 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1438 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1439 not work with the asynchronous Isar document model.
  1440 
  1441 * Configuration options now admit dynamic default values, depending on
  1442 the context or even global references.
  1443 
  1444 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1445 uses an efficient external library if available (for Poly/ML).
  1446 
  1447 * Renamed some important ML structures, while keeping the old names
  1448 for some time as aliases within the structure Legacy:
  1449 
  1450   OuterKeyword  ~>  Keyword
  1451   OuterLex      ~>  Token
  1452   OuterParse    ~>  Parse
  1453   OuterSyntax   ~>  Outer_Syntax
  1454   PrintMode     ~>  Print_Mode
  1455   SpecParse     ~>  Parse_Spec
  1456   ThyInfo       ~>  Thy_Info
  1457   ThyLoad       ~>  Thy_Load
  1458   ThyOutput     ~>  Thy_Output
  1459   TypeInfer     ~>  Type_Infer
  1460 
  1461 Note that "open Legacy" simplifies porting of sources, but forgetting
  1462 to remove it again will complicate porting again in the future.
  1463 
  1464 * Most operations that refer to a global context are named
  1465 accordingly, e.g. Simplifier.global_context or
  1466 ProofContext.init_global.  There are some situations where a global
  1467 context actually works, but under normal circumstances one needs to
  1468 pass the proper local context through the code!
  1469 
  1470 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1471 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1472 Pretty.pp argument to merge, which is absent in the standard
  1473 Theory_Data version.
  1474 
  1475 * Sorts.certify_sort and derived "cert" operations for types and terms
  1476 no longer minimize sorts.  Thus certification at the boundary of the
  1477 inference kernel becomes invariant under addition of class relations,
  1478 which is an important monotonicity principle.  Sorts are now minimized
  1479 in the syntax layer only, at the boundary between the end-user and the
  1480 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1481 explicitly in rare situations.
  1482 
  1483 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1484 emphasize that this is in no way a standard operation.
  1485 INCOMPATIBILITY.
  1486 
  1487 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1488 usual for resolution.  Rare INCOMPATIBILITY.
  1489 
  1490 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1491 to emphasize that these only work in a global situation (which is
  1492 quite rare).
  1493 
  1494 * Curried take and drop in library.ML; negative length is interpreted
  1495 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1496 
  1497 * Proof terms: type substitutions on proof constants now use canonical
  1498 order of type variables.  INCOMPATIBILITY for tools working with proof
  1499 terms.
  1500 
  1501 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1502 may no longer carry premises.  User-level specifications are
  1503 transformed accordingly by Thm.add_axiom/add_def.
  1504 
  1505 
  1506 *** System ***
  1507 
  1508 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1509 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1510 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1511 
  1512 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1513 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1514 respectively.
  1515 
  1516 * Old lib/scripts/polyml-platform is superseded by the
  1517 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1518 variant, even on a 64 bit machine.  The following example setting
  1519 prefers 64 bit if available:
  1520 
  1521   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1522 
  1523 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1524 Isabelle/Scala layer for advanced prover interaction and integration.
  1525 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1526 component.
  1527 
  1528 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1529 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1530 similar to the default assignment of the document preparation system
  1531 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1532 provides some operations for direct access to the font without asking
  1533 the user for manual installation.
  1534 
  1535 
  1536 
  1537 New in Isabelle2009-1 (December 2009)
  1538 -------------------------------------
  1539 
  1540 *** General ***
  1541 
  1542 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1543 one backslash should be used, even in ML sources.
  1544 
  1545 
  1546 *** Pure ***
  1547 
  1548 * Locale interpretation propagates mixins along the locale hierarchy.
  1549 The currently only available mixins are the equations used to map
  1550 local definitions to terms of the target domain of an interpretation.
  1551 
  1552 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1553 loc" to print all interpretations of locale "loc" in the theory.
  1554 Interpretations in proofs are not shown.
  1555 
  1556 * Thoroughly revised locales tutorial.  New section on conditional
  1557 interpretation.
  1558 
  1559 * On instantiation of classes, remaining undefined class parameters
  1560 are formally declared.  INCOMPATIBILITY.
  1561 
  1562 
  1563 *** Document preparation ***
  1564 
  1565 * New generalized style concept for printing terms: @{foo (style) ...}
  1566 instead of @{foo_style style ...}  (old form is still retained for
  1567 backward compatibility).  Styles can be also applied for
  1568 antiquotations prop, term_type and typeof.
  1569 
  1570 
  1571 *** HOL ***
  1572 
  1573 * New proof method "smt" for a combination of first-order logic with
  1574 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1575 fixed-size bitvectors; there is also basic support for higher-order
  1576 features (esp. lambda abstractions).  It is an incomplete decision
  1577 procedure based on external SMT solvers using the oracle mechanism;
  1578 for the SMT solver Z3, this method is proof-producing.  Certificates
  1579 are provided to avoid calling the external solvers solely for
  1580 re-checking proofs.  Due to a remote SMT service there is no need for
  1581 installing SMT solvers locally.  See src/HOL/SMT.
  1582 
  1583 * New commands to load and prove verification conditions generated by
  1584 the Boogie program verifier or derived systems (e.g. the Verifying C
  1585 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1586 
  1587 * New counterexample generator tool 'nitpick' based on the Kodkod
  1588 relational model finder.  See src/HOL/Tools/Nitpick and
  1589 src/HOL/Nitpick_Examples.
  1590 
  1591 * New commands 'code_pred' and 'values' to invoke the predicate
  1592 compiler and to enumerate values of inductive predicates.
  1593 
  1594 * A tabled implementation of the reflexive transitive closure.
  1595 
  1596 * New implementation of quickcheck uses generic code generator;
  1597 default generators are provided for all suitable HOL types, records
  1598 and datatypes.  Old quickcheck can be re-activated importing theory
  1599 Library/SML_Quickcheck.
  1600 
  1601 * New testing tool Mirabelle for automated proof tools.  Applies
  1602 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1603 every proof step in a theory.  To be used in batch mode via the
  1604 "mirabelle" utility.
  1605 
  1606 * New proof method "sos" (sum of squares) for nonlinear real
  1607 arithmetic (originally due to John Harison). It requires theory
  1608 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1609 works well in practice on quantifier-free real arithmetic with +, -,
  1610 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1611 inequalities between polynomials.  It makes use of external
  1612 semidefinite programming solvers.  Method "sos" generates a
  1613 certificate that can be pasted into the proof thus avoiding the need
  1614 to call an external tool every time the proof is checked.  See
  1615 src/HOL/Library/Sum_Of_Squares.
  1616 
  1617 * New method "linarith" invokes existing linear arithmetic decision
  1618 procedure only.
  1619 
  1620 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1621 
  1622 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1623 Causes full type information to be output to the ATPs.  This slows
  1624 ATPs down considerably but eliminates a source of unsound "proofs"
  1625 that fail later.
  1626 
  1627 * New method "metisFT": A version of metis that uses full type
  1628 information in order to avoid failures of proof reconstruction.
  1629 
  1630 * New evaluator "approximate" approximates an real valued term using
  1631 the same method as the approximation method.
  1632 
  1633 * Method "approximate" now supports arithmetic expressions as
  1634 boundaries of intervals and implements interval splitting and Taylor
  1635 series expansion.
  1636 
  1637 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1638 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1639 
  1640 * New theory SupInf of the supremum and infimum operators for sets of
  1641 reals.
  1642 
  1643 * New theory Probability, which contains a development of measure
  1644 theory, eventually leading to Lebesgue integration and probability.
  1645 
  1646 * Extended Multivariate Analysis to include derivation and Brouwer's
  1647 fixpoint theorem.
  1648 
  1649 * Reorganization of number theory, INCOMPATIBILITY:
  1650   - new number theory development for nat and int, in theories Divides
  1651     and GCD as well as in new session Number_Theory
  1652   - some constants and facts now suffixed with _nat and _int
  1653     accordingly
  1654   - former session NumberTheory now named Old_Number_Theory, including
  1655     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1656   - moved theory Pocklington from src/HOL/Library to
  1657     src/HOL/Old_Number_Theory
  1658 
  1659 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1660 lcm of finite and infinite sets. It is shown that they form a complete
  1661 lattice.
  1662 
  1663 * Class semiring_div requires superclass no_zero_divisors and proof of
  1664 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1665 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1666 generalized to class semiring_div, subsuming former theorems
  1667 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1668 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1669 INCOMPATIBILITY.
  1670 
  1671 * Refinements to lattice classes and sets:
  1672   - less default intro/elim rules in locale variant, more default
  1673     intro/elim rules in class variant: more uniformity
  1674   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1675     le_inf_iff
  1676   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1677     sup_aci)
  1678   - renamed ACI to inf_sup_aci
  1679   - new class "boolean_algebra"
  1680   - class "complete_lattice" moved to separate theory
  1681     "Complete_Lattice"; corresponding constants (and abbreviations)
  1682     renamed and with authentic syntax:
  1683     Set.Inf ~>    Complete_Lattice.Inf
  1684     Set.Sup ~>    Complete_Lattice.Sup
  1685     Set.INFI ~>   Complete_Lattice.INFI
  1686     Set.SUPR ~>   Complete_Lattice.SUPR
  1687     Set.Inter ~>  Complete_Lattice.Inter
  1688     Set.Union ~>  Complete_Lattice.Union
  1689     Set.INTER ~>  Complete_Lattice.INTER
  1690     Set.UNION ~>  Complete_Lattice.UNION
  1691   - authentic syntax for
  1692     Set.Pow
  1693     Set.image
  1694   - mere abbreviations:
  1695     Set.empty               (for bot)
  1696     Set.UNIV                (for top)
  1697     Set.inter               (for inf, formerly Set.Int)
  1698     Set.union               (for sup, formerly Set.Un)
  1699     Complete_Lattice.Inter  (for Inf)
  1700     Complete_Lattice.Union  (for Sup)
  1701     Complete_Lattice.INTER  (for INFI)
  1702     Complete_Lattice.UNION  (for SUPR)
  1703   - object-logic definitions as far as appropriate
  1704 
  1705 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1706 Un_subset_iff are explicitly deleted as default simp rules; then also
  1707 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1708 deleted to achieve the desired effect.
  1709 
  1710 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1711 rules by default any longer; the same applies to min_max.inf_absorb1
  1712 etc.  INCOMPATIBILITY.
  1713 
  1714 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1715 pred_set_conv by default.  INCOMPATIBILITY.
  1716 
  1717 * Power operations on relations and functions are now one dedicated
  1718 constant "compow" with infix syntax "^^".  Power operation on
  1719 multiplicative monoids retains syntax "^" and is now defined generic
  1720 in class power.  INCOMPATIBILITY.
  1721 
  1722 * Relation composition "R O S" now has a more standard argument order:
  1723 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1724 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1725 break, since the O_assoc rule was not rewritten like this.  Fix using
  1726 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1727 
  1728 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1729 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1730 INCOMPATIBILITY.
  1731 
  1732 * Most rules produced by inductive and datatype package have mandatory
  1733 prefixes.  INCOMPATIBILITY.
  1734 
  1735 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1736 the attribute of the same name.  Each of the theorems in the list
  1737 DERIV_intros assumes composition with an additional function and
  1738 matches a variable to the derivative, which has to be solved by the
  1739 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1740 of most elementary terms.  Former Maclauren.DERIV_tac and
  1741 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1742 INCOMPATIBILITY.
  1743 
  1744 * Code generator attributes follow the usual underscore convention:
  1745     code_unfold     replaces    code unfold
  1746     code_post       replaces    code post
  1747     etc.
  1748   INCOMPATIBILITY.
  1749 
  1750 * Renamed methods:
  1751     sizechange -> size_change
  1752     induct_scheme -> induction_schema
  1753   INCOMPATIBILITY.
  1754 
  1755 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1756 INCOMPATIBILITY, use "undefined" directly.
  1757 
  1758 * Renamed theorems:
  1759     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1760     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1761     Suc_plus1 -> Suc_eq_plus1
  1762     *anti_sym -> *antisym*
  1763     vector_less_eq_def -> vector_le_def
  1764   INCOMPATIBILITY.
  1765 
  1766 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1767 INCOMPATIBILITY.
  1768 
  1769 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1770 INCOMPATIBILITY.
  1771 
  1772 
  1773 *** HOLCF ***
  1774 
  1775 * Theory Representable defines a class "rep" of domains that are
  1776 representable (via an ep-pair) in the universal domain type "udom".
  1777 Instances are provided for all type constructors defined in HOLCF.
  1778 
  1779 * The 'new_domain' command is a purely definitional version of the
  1780 domain package, for representable domains.  Syntax is identical to the
  1781 old domain package.  The 'new_domain' package also supports indirect
  1782 recursion using previously-defined type constructors.  See
  1783 src/HOLCF/ex/New_Domain.thy for examples.
  1784 
  1785 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1786 on the left-hand side of an equation, and then performs
  1787 simplification.  Rewriting is done using rules declared with the
  1788 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1789 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1790 
  1791 * The pattern-match compiler in 'fixrec' can now handle constructors
  1792 with HOL function types.  Pattern-match combinators for the Pair
  1793 constructor are pre-configured.
  1794 
  1795 * The 'fixrec' package now produces better fixed-point induction rules
  1796 for mutually-recursive definitions:  Induction rules have conclusions
  1797 of the form "P foo bar" instead of "P <foo, bar>".
  1798 
  1799 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1800 been renamed to "below".  The name "below" now replaces "less" in many
  1801 theorem names.  (Legacy theorem names using "less" are still supported
  1802 as well.)
  1803 
  1804 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1805 patterns can be used to generate strictness rules, or to make
  1806 functions more strict (much like the bang-patterns supported by the
  1807 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1808 examples.
  1809 
  1810 
  1811 *** ML ***
  1812 
  1813 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1814 errors and run-time exceptions, including detailed source positions.
  1815 
  1816 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1817 identified entries, with some additional information such as source
  1818 position, logical grouping etc.
  1819 
  1820 * Theory and context data is now introduced by the simplified and
  1821 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1822 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1823 copy operation) is still available for some time.
  1824 
  1825 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1826 provides a high-level programming interface to synchronized state
  1827 variables with atomic update.  This works via pure function
  1828 application within a critical section -- its runtime should be as
  1829 short as possible; beware of deadlocks if critical code is nested,
  1830 either directly or indirectly via other synchronized variables!
  1831 
  1832 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1833 wraps raw ML references, explicitly indicating their non-thread-safe
  1834 behaviour.  The Isar toplevel keeps this structure open, to
  1835 accommodate Proof General as well as quick and dirty interactive
  1836 experiments with references.
  1837 
  1838 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1839 parallel tactical reasoning.
  1840 
  1841 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1842 are similar to SUBPROOF, but are slightly more flexible: only the
  1843 specified parts of the subgoal are imported into the context, and the
  1844 body tactic may introduce new subgoals and schematic variables.
  1845 
  1846 * Old tactical METAHYPS, which does not observe the proof context, has
  1847 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1848 or Subgoal.FOCUS etc.
  1849 
  1850 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1851 functors have their own ML name space there is no point to mark them
  1852 separately.)  Minor INCOMPATIBILITY.
  1853 
  1854 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1855 
  1856 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1857 INCOMPATIBILITY.
  1858 
  1859 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1860 mode, which avoids critical setmp.
  1861 
  1862 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1863 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1864 Attrib/Method.setup introduced in Isabelle2009.
  1865 
  1866 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1867 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1868 last resort.  INCOMPATIBILITY.
  1869 
  1870 * Display.pretty_thm now requires a proper context (cf. former
  1871 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1872 or even Display.pretty_thm_without_context as last resort.
  1873 INCOMPATIBILITY.
  1874 
  1875 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1876 Syntax.pretty_typ/term directly, preferably with proper context
  1877 instead of global theory.
  1878 
  1879 
  1880 *** System ***
  1881 
  1882 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1883 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1884 usedir option -q.
  1885 
  1886 * Support for additional "Isabelle components" via etc/components, see
  1887 also the system manual.
  1888 
  1889 * The isabelle makeall tool now operates on all components with
  1890 IsaMakefile, not just hardwired "logics".
  1891 
  1892 * Removed "compress" option from isabelle-process and isabelle usedir;
  1893 this is always enabled.
  1894 
  1895 * Discontinued support for Poly/ML 4.x versions.
  1896 
  1897 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  1898 on a given logic image.  This requires the lighttpd webserver and is
  1899 currently supported on Linux only.
  1900 
  1901 
  1902 
  1903 New in Isabelle2009 (April 2009)
  1904 --------------------------------
  1905 
  1906 *** General ***
  1907 
  1908 * Simplified main Isabelle executables, with less surprises on
  1909 case-insensitive file-systems (such as Mac OS).
  1910 
  1911   - The main Isabelle tool wrapper is now called "isabelle" instead of
  1912     "isatool."
  1913 
  1914   - The former "isabelle" alias for "isabelle-process" has been
  1915     removed (should rarely occur to regular users).
  1916 
  1917   - The former "isabelle-interface" and its alias "Isabelle" have been
  1918     removed (interfaces are now regular Isabelle tools).
  1919 
  1920 Within scripts and make files, the Isabelle environment variables
  1921 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  1922 respectively.  (The latter are still available as legacy feature.)
  1923 
  1924 The old isabelle-interface wrapper could react in confusing ways if
  1925 the interface was uninstalled or changed otherwise.  Individual
  1926 interface tool configuration is now more explicit, see also the
  1927 Isabelle system manual.  In particular, Proof General is now available
  1928 via "isabelle emacs".
  1929 
  1930 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  1931 purge installed copies of Isabelle executables and re-run "isabelle
  1932 install -p ...", or use symlinks.
  1933 
  1934 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  1935 old ~/isabelle, which was slightly non-standard and apt to cause
  1936 surprises on case-insensitive file-systems (such as Mac OS).
  1937 
  1938 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  1939 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  1940 care is required when using older releases of Isabelle.  Note that
  1941 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  1942 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  1943 
  1944 * Proofs of fully specified statements are run in parallel on
  1945 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  1946 a regular 4-core machine, if the initial heap space is made reasonably
  1947 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  1948 
  1949 * The main reference manuals ("isar-ref", "implementation", and
  1950 "system") have been updated and extended.  Formally checked references
  1951 as hyperlinks are now available uniformly.
  1952 
  1953 
  1954 *** Pure ***
  1955 
  1956 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  1957 respects.  The most important changes are listed below.  See the
  1958 Tutorial on Locales ("locales" manual) for details.
  1959 
  1960 - In locale expressions, instantiation replaces renaming.  Parameters
  1961 must be declared in a for clause.  To aid compatibility with previous
  1962 parameter inheritance, in locale declarations, parameters that are not
  1963 'touched' (instantiation position "_" or omitted) are implicitly added
  1964 with their syntax at the beginning of the for clause.
  1965 
  1966 - Syntax from abbreviations and definitions in locales is available in
  1967 locale expressions and context elements.  The latter is particularly
  1968 useful in locale declarations.
  1969 
  1970 - More flexible mechanisms to qualify names generated by locale
  1971 expressions.  Qualifiers (prefixes) may be specified in locale
  1972 expressions, and can be marked as mandatory (syntax: "name!:") or
  1973 optional (syntax "name?:").  The default depends for plain "name:"
  1974 depends on the situation where a locale expression is used: in
  1975 commands 'locale' and 'sublocale' prefixes are optional, in
  1976 'interpretation' and 'interpret' prefixes are mandatory.  The old
  1977 implicit qualifiers derived from the parameter names of a locale are
  1978 no longer generated.
  1979 
  1980 - Command "sublocale l < e" replaces "interpretation l < e".  The
  1981 instantiation clause in "interpretation" and "interpret" (square
  1982 brackets) is no longer available.  Use locale expressions.
  1983 
  1984 - When converting proof scripts, mandatory qualifiers in
  1985 'interpretation' and 'interpret' should be retained by default, even
  1986 if this is an INCOMPATIBILITY compared to former behavior.  In the
  1987 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  1988 in locale expressions range over a single locale instance only.
  1989 
  1990 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  1991 In existing theorem specifications replace the includes element by the
  1992 respective context elements of the included locale, omitting those
  1993 that are already present in the theorem specification.  Multiple
  1994 assume elements of a locale should be replaced by a single one
  1995 involving the locale predicate.  In the proof body, declarations (most
  1996 notably theorems) may be regained by interpreting the respective
  1997 locales in the proof context as required (command "interpret").
  1998 
  1999 If using "includes" in replacement of a target solely because the
  2000 parameter types in the theorem are not as general as in the target,
  2001 consider declaring a new locale with additional type constraints on
  2002 the parameters (context element "constrains").
  2003 
  2004 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2005 
  2006 - Locale interpretation commands no longer attempt to simplify goal.
  2007 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2008 methods intro_locales and unfold_locales to clarify.
  2009 
  2010 - Locale interpretation commands no longer accept interpretation
  2011 attributes.  INCOMPATIBILITY.
  2012 
  2013 * Class declaration: so-called "base sort" must not be given in import
  2014 list any longer, but is inferred from the specification.  Particularly
  2015 in HOL, write
  2016 
  2017     class foo = ...
  2018 
  2019 instead of
  2020 
  2021     class foo = type + ...
  2022 
  2023 * Class target: global versions of theorems stemming do not carry a
  2024 parameter prefix any longer.  INCOMPATIBILITY.
  2025 
  2026 * Class 'instance' command no longer accepts attached definitions.
  2027 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2028 
  2029 * Recovered hiding of consts, which was accidentally broken in
  2030 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2031 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2032 
  2033 * Slightly more coherent Pure syntax, with updated documentation in
  2034 isar-ref manual.  Removed locales meta_term_syntax and
  2035 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2036 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2037 directly in regular applications.
  2038 
  2039 * There is a new syntactic category "float_const" for signed decimal
  2040 fractions (e.g. 123.45 or -123.45).
  2041 
  2042 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2043 interface with 'setup' command instead.
  2044 
  2045 * Command 'local_setup' is similar to 'setup', but operates on a local
  2046 theory context.
  2047 
  2048 * The 'axiomatization' command now only works within a global theory
  2049 context.  INCOMPATIBILITY.
  2050 
  2051 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2052 hypotheses.  Sorts required in the course of reasoning need to be
  2053 covered by the constraints in the initial statement, completed by the
  2054 type instance information of the background theory.  Non-trivial sort
  2055 hypotheses, which rarely occur in practice, may be specified via
  2056 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2057 
  2058   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2059 
  2060 The result contains an implicit sort hypotheses as before --
  2061 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2062 normalization.
  2063 
  2064 * Generalized Isar history, with support for linear undo, direct state
  2065 addressing etc.
  2066 
  2067 * Changed defaults for unify configuration options:
  2068 
  2069   unify_trace_bound = 50 (formerly 25)
  2070   unify_search_bound = 60 (formerly 30)
  2071 
  2072 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2073 
  2074   a) On theory merge, the last set of code equations for a particular
  2075      constant is taken (in accordance with the policy applied by other
  2076      parts of the code generator framework).
  2077 
  2078   b) Code equations stemming from explicit declarations (e.g. code
  2079      attribute) gain priority over default code equations stemming
  2080      from definition, primrec, fun etc.
  2081 
  2082 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2083 
  2084 * Unified theorem tables for both code generators.  Thus [code
  2085 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2086 
  2087 * Command 'find_consts' searches for constants based on type and name
  2088 patterns, e.g.
  2089 
  2090     find_consts "_ => bool"
  2091 
  2092 By default, matching is against subtypes, but it may be restricted to
  2093 the whole type.  Searching by name is possible.  Multiple queries are
  2094 conjunctive and queries may be negated by prefixing them with a
  2095 hyphen:
  2096 
  2097     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2098 
  2099 * New 'find_theorems' criterion "solves" matches theorems that
  2100 directly solve the current goal (modulo higher-order unification).
  2101 
  2102 * Auto solve feature for main theorem statements: whenever a new goal
  2103 is stated, "find_theorems solves" is called; any theorems that could
  2104 solve the lemma directly are listed as part of the goal state.
  2105 Cf. associated options in Proof General Isabelle settings menu,
  2106 enabled by default, with reasonable timeout for pathological cases of
  2107 higher-order unification.
  2108 
  2109 
  2110 *** Document preparation ***
  2111 
  2112 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2113 demanding keyword 'by' and supporting the full method expression
  2114 syntax just like the Isar command 'by'.
  2115 
  2116 
  2117 *** HOL ***
  2118 
  2119 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2120 points Main and Complex_Main remain as before.
  2121 
  2122 * Logic image HOL-Plain provides a minimal HOL with the most important
  2123 tools available (inductive, datatype, primrec, ...).  This facilitates
  2124 experimentation and tool development.  Note that user applications
  2125 (and library theories) should never refer to anything below theory
  2126 Main, as before.
  2127 
  2128 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2129 experimentation due to shorter build times.
  2130 
  2131 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2132 were previously part of former HOL-Complex.  Entry point Hyperreal
  2133 remains valid, but theories formerly using Complex_Main should now use
  2134 new entry point Hypercomplex.
  2135 
  2136 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2137 Posix processes.  Avoids potentially expensive forking of the ML
  2138 process.  New thread-based implementation also works on non-Unix
  2139 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2140 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2141 commands are covered in the isar-ref manual.
  2142 
  2143 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2144 sledgehammer without local ATP installation (Vampire etc.). Other
  2145 provers may be included via suitable ML wrappers, see also
  2146 src/HOL/ATP_Linkup.thy.
  2147 
  2148 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2149 menu.
  2150 
  2151 * The metis method no longer fails because the theorem is too trivial
  2152 (contains the empty clause).
  2153 
  2154 * The metis method now fails in the usual manner, rather than raising
  2155 an exception, if it determines that it cannot prove the theorem.
  2156 
  2157 * Method "coherent" implements a prover for coherent logic (see also
  2158 src/Tools/coherent.ML).
  2159 
  2160 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2161 "undefined" is the right choice to replace "arbitrary", though
  2162 logically there is no difference.  INCOMPATIBILITY.
  2163 
  2164 * Command "value" now integrates different evaluation mechanisms.  The
  2165 result of the first successful evaluation mechanism is printed.  In
  2166 square brackets a particular named evaluation mechanisms may be
  2167 specified (currently, [SML], [code] or [nbe]).  See further
  2168 src/HOL/ex/Eval_Examples.thy.
  2169 
  2170 * Normalization by evaluation now allows non-leftlinear equations.
  2171 Declare with attribute [code nbe].
  2172 
  2173 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2174 as the structured Isar versions "cases" and "induct", cf. the
  2175 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2176 are now presented as a list of individual projections
  2177 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2178 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2179 rare situations a different rule is selected --- notably nested tuple
  2180 elimination instead of former prod.exhaust: use explicit (case_tac t
  2181 rule: prod.exhaust) here.
  2182 
  2183 * Attributes "cases", "induct", "coinduct" support "del" option.
  2184 
  2185 * Removed fact "case_split_thm", which duplicates "case_split".
  2186 
  2187 * The option datatype has been moved to a new theory Option.  Renamed
  2188 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2189 
  2190 * New predicate "strict_mono" classifies strict functions on partial
  2191 orders.  With strict functions on linear orders, reasoning about
  2192 (in)equalities is facilitated by theorems "strict_mono_eq",
  2193 "strict_mono_less_eq" and "strict_mono_less".
  2194 
  2195 * Some set operations are now proper qualified constants with
  2196 authentic syntax.  INCOMPATIBILITY:
  2197 
  2198     op Int ~>   Set.Int
  2199     op Un ~>    Set.Un
  2200     INTER ~>    Set.INTER
  2201     UNION ~>    Set.UNION
  2202     Inter ~>    Set.Inter
  2203     Union ~>    Set.Union
  2204     {} ~>       Set.empty
  2205     UNIV ~>     Set.UNIV
  2206 
  2207 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2208 theory Set.
  2209 
  2210 * Auxiliary class "itself" has disappeared -- classes without any
  2211 parameter are treated as expected by the 'class' command.
  2212 
  2213 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2214 
  2215 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2216 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2217 
  2218 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2219 method "approximation".  It proves formulas on real values by using
  2220 interval arithmetic.  In the formulas are also the transcendental
  2221 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2222 allowed. For examples see
  2223 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2224 
  2225 * Theory "Reflection" now resides in HOL/Library.
  2226 
  2227 * Entry point to Word library now simply named "Word".
  2228 INCOMPATIBILITY.
  2229 
  2230 * Made source layout more coherent with logical distribution
  2231 structure:
  2232 
  2233     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2234     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2235     src/HOL/Library/GCD.thy ~> src/HOL/
  2236     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2237     src/HOL/Library/Parity.thy ~> src/HOL/
  2238     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2239     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2240     src/HOL/Real/Lubs.thy ~> src/HOL/
  2241     src/HOL/Real/PReal.thy ~> src/HOL/
  2242     src/HOL/Real/Rational.thy ~> src/HOL/
  2243     src/HOL/Real/RComplete.thy ~> src/HOL/
  2244     src/HOL/Real/RealDef.thy ~> src/HOL/
  2245     src/HOL/Real/RealPow.thy ~> src/HOL/
  2246     src/HOL/Real/Real.thy ~> src/HOL/
  2247     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2248     src/HOL/Complex/Complex.thy ~> src/HOL/
  2249     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2250     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2251     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2252     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2253     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2254     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2255     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2256     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2257     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2258     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2259     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2260     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2261     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2262     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2263     src/HOL/Real/Float ~> src/HOL/Library/
  2264     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2265     src/HOL/Real/RealVector.thy ~> src/HOL/
  2266 
  2267     src/HOL/arith_data.ML ~> src/HOL/Tools
  2268     src/HOL/hologic.ML ~> src/HOL/Tools
  2269     src/HOL/simpdata.ML ~> src/HOL/Tools
  2270     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2271     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2272     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2273     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2274     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2275     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2276     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2277 
  2278     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2279     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2280     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2281     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2282     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2283     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2284 
  2285 * If methods "eval" and "evaluation" encounter a structured proof
  2286 state with !!/==>, only the conclusion is evaluated to True (if
  2287 possible), avoiding strange error messages.
  2288 
  2289 * Method "sizechange" automates termination proofs using (a
  2290 modification of) the size-change principle.  Requires SAT solver.  See
  2291 src/HOL/ex/Termination.thy for examples.
  2292 
  2293 * Simplifier: simproc for let expressions now unfolds if bound
  2294 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2295 
  2296 * Method "arith": Linear arithmetic now ignores all inequalities when
  2297 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2298 
  2299 * New attribute "arith" for facts that should always be used
  2300 automatically by arithmetic. It is intended to be used locally in
  2301 proofs, e.g.
  2302 
  2303   assumes [arith]: "x > 0"
  2304 
  2305 Global usage is discouraged because of possible performance impact.
  2306 
  2307 * New classes "top" and "bot" with corresponding operations "top" and
  2308 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2309 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2310 
  2311 * Changed definition lemma "less_fun_def" in order to provide an
  2312 instance for preorders on functions; use lemma "less_le" instead.
  2313 INCOMPATIBILITY.
  2314 
  2315 * Theory Orderings: class "wellorder" moved here, with explicit
  2316 induction rule "less_induct" as assumption.  For instantiation of
  2317 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2318 INCOMPATIBILITY.
  2319 
  2320 * Theory Orderings: added class "preorder" as superclass of "order".
  2321 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2322 etc. slightly changed.  Some theorems named order_class.* now named
  2323 preorder_class.*.
  2324 
  2325 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2326 "diag" to "Id_on".
  2327 
  2328 * Theory Finite_Set: added a new fold combinator of type
  2329 
  2330   ('a => 'b => 'b) => 'b => 'a set => 'b
  2331 
  2332 Occasionally this is more convenient than the old fold combinator
  2333 which is now defined in terms of the new one and renamed to
  2334 fold_image.
  2335 
  2336 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2337 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2338 extended with further lemmas!).  At the moment both still exist but
  2339 the former will disappear at some point.
  2340 
  2341 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2342 class recpower.  Type-specific simp rules for various recpower types
  2343 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2344 
  2345 rat_power_0    -> power_0
  2346 rat_power_Suc  -> power_Suc
  2347 realpow_0      -> power_0
  2348 realpow_Suc    -> power_Suc
  2349 complexpow_0   -> power_0
  2350 complexpow_Suc -> power_Suc
  2351 power_poly_0   -> power_0
  2352 power_poly_Suc -> power_Suc
  2353 
  2354 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2355 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2356 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2357 of lemmas from Divides has been generalized from nat to class
  2358 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2359 renames resulting from duplicate elimination:
  2360 
  2361     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2362     zero_dvd_iff ~>         dvd_0_left_iff
  2363     dvd_0 ~>                dvd_0_right
  2364     DIVISION_BY_ZERO_DIV ~> div_by_0
  2365     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2366     mult_div ~>             div_mult_self2_is_id
  2367     mult_mod ~>             mod_mult_self2_is_0
  2368 
  2369 * Theory IntDiv: removed many lemmas that are instances of class-based
  2370 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2371 rename old lemmas as follows:
  2372 
  2373 dvd_diff               -> nat_dvd_diff
  2374 dvd_zminus_iff         -> dvd_minus_iff
  2375 mod_add1_eq            -> mod_add_eq
  2376 mod_mult1_eq           -> mod_mult_right_eq
  2377 mod_mult1_eq'          -> mod_mult_left_eq
  2378 mod_mult_distrib_mod   -> mod_mult_eq
  2379 nat_mod_add_left_eq    -> mod_add_left_eq
  2380 nat_mod_add_right_eq   -> mod_add_right_eq
  2381 nat_mod_div_trivial    -> mod_div_trivial
  2382 nat_mod_mod_trivial    -> mod_mod_trivial
  2383 zdiv_zadd_self1        -> div_add_self1
  2384 zdiv_zadd_self2        -> div_add_self2
  2385 zdiv_zmult_self1       -> div_mult_self2_is_id
  2386 zdiv_zmult_self2       -> div_mult_self1_is_id
  2387 zdvd_triv_left         -> dvd_triv_left
  2388 zdvd_triv_right        -> dvd_triv_right
  2389 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2390 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2391 zmod_zadd_left_eq      -> mod_add_left_eq
  2392 zmod_zadd_right_eq     -> mod_add_right_eq
  2393 zmod_zadd_self1        -> mod_add_self1
  2394 zmod_zadd_self2        -> mod_add_self2
  2395 zmod_zadd1_eq          -> mod_add_eq
  2396 zmod_zdiff1_eq         -> mod_diff_eq
  2397 zmod_zdvd_zmod         -> mod_mod_cancel
  2398 zmod_zmod_cancel       -> mod_mod_cancel
  2399 zmod_zmult_self1       -> mod_mult_self2_is_0
  2400 zmod_zmult_self2       -> mod_mult_self1_is_0
  2401 zmod_1                 -> mod_by_1
  2402 zdiv_1                 -> div_by_1
  2403 zdvd_abs1              -> abs_dvd_iff
  2404 zdvd_abs2              -> dvd_abs_iff
  2405 zdvd_refl              -> dvd_refl
  2406 zdvd_trans             -> dvd_trans
  2407 zdvd_zadd              -> dvd_add
  2408 zdvd_zdiff             -> dvd_diff
  2409 zdvd_zminus_iff        -> dvd_minus_iff
  2410 zdvd_zminus2_iff       -> minus_dvd_iff
  2411 zdvd_zmultD            -> dvd_mult_right
  2412 zdvd_zmultD2           -> dvd_mult_left
  2413 zdvd_zmult_mono        -> mult_dvd_mono
  2414 zdvd_0_right           -> dvd_0_right
  2415 zdvd_0_left            -> dvd_0_left_iff
  2416 zdvd_1_left            -> one_dvd
  2417 zminus_dvd_iff         -> minus_dvd_iff
  2418 
  2419 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2420 
  2421 * The real numbers offer decimal input syntax: 12.34 is translated
  2422 into 1234/10^2. This translation is not reversed upon output.
  2423 
  2424 * Theory Library/Polynomial defines an abstract type 'a poly of
  2425 univariate polynomials with coefficients of type 'a.  In addition to
  2426 the standard ring operations, it also supports div and mod.  Code
  2427 generation is also supported, using list-style constructors.
  2428 
  2429 * Theory Library/Inner_Product defines a class of real_inner for real
  2430 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2431 => real.  Class real_inner is a subclass of real_normed_vector from
  2432 theory RealVector.
  2433 
  2434 * Theory Library/Product_Vector provides instances for the product
  2435 type 'a * 'b of several classes from RealVector and Inner_Product.
  2436 Definitions of addition, subtraction, scalar multiplication, norms,
  2437 and inner products are included.
  2438 
  2439 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2440 addition to the field operations, numerals and case syntax are also
  2441 supported.
  2442 
  2443 * Theory Library/Diagonalize provides constructive version of Cantor's
  2444 first diagonalization argument.
  2445 
  2446 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2447 zlcm (for int); carried together from various gcd/lcm developements in
  2448 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2449 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2450 may recover tupled syntax as follows:
  2451 
  2452     hide (open) const gcd
  2453     abbreviation gcd where
  2454       "gcd == (%(a, b). GCD.gcd a b)"
  2455     notation (output)
  2456       GCD.gcd ("gcd '(_, _')")
  2457 
  2458 The same works for lcm, zgcd, zlcm.
  2459 
  2460 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2461 instantiations for algebraic structures.  Removed some duplicate
  2462 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2463 
  2464 * ML antiquotation @{code} takes a constant as argument and generates
  2465 corresponding code in background and inserts name of the corresponding
  2466 resulting ML value/function/datatype constructor binding in place.
  2467 All occurrences of @{code} with a single ML block are generated
  2468 simultaneously.  Provides a generic and safe interface for
  2469 instrumentalizing code generation.  See
  2470 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2471 In future you ought to refrain from ad-hoc compiling generated SML
  2472 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2473 cannot refer to constants for which user-defined serializations are
  2474 set.  Refer to the corresponding ML counterpart directly in that
  2475 cases.
  2476 
  2477 * Command 'rep_datatype': instead of theorem names the command now
  2478 takes a list of terms denoting the constructors of the type to be
  2479 represented as datatype.  The characteristic theorems have to be
  2480 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2481 have disappeared in favour of existing ones:
  2482 
  2483     unit_induct                 ~> unit.induct
  2484     prod_induct                 ~> prod.induct
  2485     sum_induct                  ~> sum.induct
  2486     Suc_Suc_eq                  ~> nat.inject
  2487     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2488 
  2489 
  2490 *** HOL-Algebra ***
  2491 
  2492 * New locales for orders and lattices where the equivalence relation
  2493 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2494 locales use a record structure with field eq for the equivalence.
  2495 
  2496 * New theory of factorial domains.
  2497 
  2498 * Units_l_inv and Units_r_inv are now simp rules by default.
  2499 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2500 and/or r_inv will now also require deletion of these lemmas.
  2501 
  2502 * Renamed the following theorems, INCOMPATIBILITY:
  2503 
  2504 UpperD ~> Upper_memD
  2505 LowerD ~> Lower_memD
  2506 least_carrier ~> least_closed
  2507 greatest_carrier ~> greatest_closed
  2508 greatest_Lower_above ~> greatest_Lower_below
  2509 one_zero ~> carrier_one_zero
  2510 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2511 
  2512 
  2513 *** HOL-Nominal ***
  2514 
  2515 * Nominal datatypes can now contain type-variables.
  2516 
  2517 * Commands 'nominal_inductive' and 'equivariance' work with local
  2518 theory targets.
  2519 
  2520 * Nominal primrec can now works with local theory targets and its
  2521 specification syntax now conforms to the general format as seen in
  2522 'inductive' etc.
  2523 
  2524 * Method "perm_simp" honours the standard simplifier attributes
  2525 (no_asm), (no_asm_use) etc.
  2526 
  2527 * The new predicate #* is defined like freshness, except that on the
  2528 left hand side can be a set or list of atoms.
  2529 
  2530 * Experimental command 'nominal_inductive2' derives strong induction
  2531 principles for inductive definitions.  In contrast to
  2532 'nominal_inductive', which can only deal with a fixed number of
  2533 binders, it can deal with arbitrary expressions standing for sets of
  2534 atoms to be avoided.  The only inductive definition we have at the
  2535 moment that needs this generalisation is the typing rule for Lets in
  2536 the algorithm W:
  2537 
  2538  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2539  -----------------------------------------------------------------
  2540          Gamma |- Let x be t1 in t2 : T2
  2541 
  2542 In this rule one wants to avoid all the binders that are introduced by
  2543 "close Gamma T1".  We are looking for other examples where this
  2544 feature might be useful.  Please let us know.
  2545 
  2546 
  2547 *** HOLCF ***
  2548 
  2549 * Reimplemented the simplification procedure for proving continuity
  2550 subgoals.  The new simproc is extensible; users can declare additional
  2551 continuity introduction rules with the attribute [cont2cont].
  2552 
  2553 * The continuity simproc now uses a different introduction rule for
  2554 solving continuity subgoals on terms with lambda abstractions.  In
  2555 some rare cases the new simproc may fail to solve subgoals that the
  2556 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2557 Potential INCOMPATIBILITY.
  2558 
  2559 * Command 'fixrec': specification syntax now conforms to the general
  2560 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2561 examples.  INCOMPATIBILITY.
  2562 
  2563 
  2564 *** ZF ***
  2565 
  2566 * Proof of Zorn's Lemma for partial orders.
  2567 
  2568 
  2569 *** ML ***
  2570 
  2571 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2572 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2573 depends on multithreading, so timouts will not work before Poly/ML
  2574 5.2.1!
  2575 
  2576 * High-level support for concurrent ML programming, see
  2577 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2578 particularly convenient to organize independent functional
  2579 computations.  The concept of "synchronized variables" provides a
  2580 higher-order interface for components with shared state, avoiding the
  2581 delicate details of mutexes and condition variables.  (Requires
  2582 Poly/ML 5.2.1 or later.)
  2583 
  2584 * ML bindings produced via Isar commands are stored within the Isar
  2585 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2586 become thread-safe and work with undo as expected (concerning
  2587 top-level bindings, not side-effects on global references).
  2588 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2589 compiler at runtime; really global bindings need to be given outside a
  2590 theory.  (Requires Poly/ML 5.2 or later.)
  2591 
  2592 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2593 context.  Top-level ML bindings are stored within the proof context in
  2594 a purely sequential fashion, disregarding the nested proof structure.
  2595 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2596 proof.  (Requires Poly/ML 5.2 or later.)
  2597 
  2598 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2599 and Method.setup, as well as Isar commands 'attribute_setup' and
  2600 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2601 existing code accordingly, or use plain 'setup' together with old
  2602 Method.add_method.
  2603 
  2604 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2605 to 'a -> thm, while results are always tagged with an authentic oracle
  2606 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2607 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2608 accordingly.  Note that extra performance may be gained by producing
  2609 the cterm carefully, avoiding slow Thm.cterm_of.
  2610 
  2611 * Simplified interface for defining document antiquotations via
  2612 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2613 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2614 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2615 examples.
  2616 
  2617 * More systematic treatment of long names, abstract name bindings, and
  2618 name space operations.  Basic operations on qualified names have been
  2619 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2620 Long_Name.append.  Old type bstring has been mostly replaced by
  2621 abstract type binding (see structure Binding), which supports precise
  2622 qualification by packages and local theory targets, as well as proper
  2623 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2624 bstring values into Binding.name, or better pass through abstract
  2625 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2626 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2627 
  2628 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2629 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2630 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2631 
  2632 * Disposed old type and term read functions (Sign.read_def_typ,
  2633 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2634 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2635 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2636 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2637 resort for legacy applications.
  2638 
  2639 * Disposed old declarations, tactics, tactic combinators that refer to
  2640 the simpset or claset of an implicit theory (such as Addsimps,
  2641 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2642 embedded ML text, or local_simpset_of with a proper context passed as
  2643 explicit runtime argument.
  2644 
  2645 * Rules and tactics that read instantiations (read_instantiate,
  2646 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2647 context, which is required for parsing and type-checking.  Moreover,
  2648 the variables are specified as plain indexnames, not string encodings
  2649 thereof.  INCOMPATIBILITY.
  2650 
  2651 * Generic Toplevel.add_hook interface allows to analyze the result of
  2652 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2653 for theorem dependency output of transactions resulting in a new
  2654 theory state.
  2655 
  2656 * ML antiquotations: block-structured compilation context indicated by
  2657 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2658 
  2659   @{binding name}                         - basic name binding
  2660   @{let ?pat = term}                      - term abbreviation (HO matching)
  2661   @{note name = fact}                     - fact abbreviation
  2662   @{thm fact}                             - singleton fact (with attributes)
  2663   @{thms fact}                            - general fact (with attributes)
  2664   @{lemma prop by method}                 - singleton goal
  2665   @{lemma prop by meth1 meth2}            - singleton goal
  2666   @{lemma prop1 ... propN by method}      - general goal
  2667   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2668   @{lemma (open) ...}                     - open derivation
  2669 
  2670 
  2671 *** System ***
  2672 
  2673 * The Isabelle "emacs" tool provides a specific interface to invoke
  2674 Proof General / Emacs, with more explicit failure if that is not
  2675 installed (the old isabelle-interface script silently falls back on
  2676 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2677 installation location of the Proof General distribution.
  2678 
  2679 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2680 the Isabelle process into a JVM/Scala application.  See
  2681 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2682 process wrapper has been discontinued.)
  2683 
  2684 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2685 
  2686 * Various status messages (with exact source position information) are
  2687 emitted, if proper markup print mode is enabled.  This allows
  2688 user-interface components to provide detailed feedback on internal
  2689 prover operations.
  2690 
  2691 
  2692 
  2693 New in Isabelle2008 (June 2008)
  2694 -------------------------------
  2695 
  2696 *** General ***
  2697 
  2698 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2699 and updated, with formally checked references as hyperlinks.
  2700 
  2701 * Theory loader: use_thy (and similar operations) no longer set the
  2702 implicit ML context, which was occasionally hard to predict and in
  2703 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2704 provides a proper context already.
  2705 
  2706 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2707 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2708 'use' within a theory file will do the job.
  2709 
  2710 * Name space merge now observes canonical order, i.e. the second space
  2711 is inserted into the first one, while existing entries in the first
  2712 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2713 swap theory imports.
  2714 
  2715 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2716 INCOMPATIBILITY in identifier syntax etc.
  2717 
  2718 * Outer syntax: string tokens no longer admit escaped white space,
  2719 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2720 white space without escapes.
  2721 
  2722 * Outer syntax: string tokens may contain arbitrary character codes
  2723 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2724 "foo_bar".
  2725 
  2726 
  2727 *** Pure ***
  2728 
  2729 * Context-dependent token translations.  Default setup reverts locally
  2730 fixed variables, and adds hilite markup for undeclared frees.
  2731 
  2732 * Unused theorems can be found using the new command 'unused_thms'.
  2733 There are three ways of invoking it:
  2734 
  2735 (1) unused_thms
  2736      Only finds unused theorems in the current theory.
  2737 
  2738 (2) unused_thms thy_1 ... thy_n -
  2739      Finds unused theorems in the current theory and all of its ancestors,
  2740      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2741 
  2742 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2743      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2744      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2745      their ancestors.
  2746 
  2747 In order to increase the readability of the list produced by
  2748 unused_thms, theorems that have been created by a particular instance
  2749 of a theory command such as 'inductive' or 'function' are considered
  2750 to belong to the same "group", meaning that if at least one theorem in
  2751 this group is used, the other theorems in the same group are no longer
  2752 reported as unused.  Moreover, if all theorems in the group are
  2753 unused, only one theorem in the group is displayed.
  2754 
  2755 Note that proof objects have to be switched on in order for
  2756 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2757 usually the case when using Proof General with the default settings).
  2758 
  2759 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2760 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2761 duplicate fact bindings, or even accidental fact duplications.  Note
  2762 that tools may maintain dynamically scoped facts systematically, using
  2763 PureThy.add_thms_dynamic.
  2764 
  2765 * Command 'hide' now allows to hide from "fact" name space as well.
  2766 
  2767 * Eliminated destructive theorem database, simpset, claset, and
  2768 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2769 update of theories within ML code.
  2770 
  2771 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2772 INCOMPATIBILITY, object-logics depending on former Pure require
  2773 additional setup PureThy.old_appl_syntax_setup; object-logics
  2774 depending on former CPure need to refer to Pure.
  2775 
  2776 * Commands 'use' and 'ML' are now purely functional, operating on
  2777 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2778 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2779 INCOMPATIBILITY.
  2780 
  2781 * Command 'setup': discontinued implicit version with ML reference.
  2782 
  2783 * Instantiation target allows for simultaneous specification of class
  2784 instance operations together with an instantiation proof.
  2785 Type-checking phase allows to refer to class operations uniformly.
  2786 See src/HOL/Complex/Complex.thy for an Isar example and
  2787 src/HOL/Library/Eval.thy for an ML example.
  2788 
  2789 * Indexing of literal facts: be more serious about including only
  2790 facts from the visible specification/proof context, but not the
  2791 background context (locale etc.).  Affects `prop` notation and method
  2792 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2793 situations.
  2794 
  2795 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2796 "(open)" option, which used to expose internal bound variables to the
  2797 proof text.
  2798 
  2799 * Isar statements: removed obsolete case "rule_context".
  2800 INCOMPATIBILITY, better use explicit fixes/assumes.
  2801 
  2802 * Locale proofs: default proof step now includes 'unfold_locales';
  2803 hence 'proof' without argument may be used to unfold locale
  2804 predicates.
  2805 
  2806 
  2807 *** Document preparation ***
  2808 
  2809 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2810 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2811 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2812 spot); renamed link color from "darkblue" to "linkcolor" (default
  2813 value unchanged, can be redefined via \definecolor); no longer sets
  2814 "a4paper" option (unnecessary or even intrusive).
  2815 
  2816 * Antiquotation @{lemma A method} proves proposition A by the given
  2817 method (either a method name or a method name plus (optional) method
  2818 arguments in parentheses) and prints A just like @{prop A}.
  2819 
  2820 
  2821 *** HOL ***
  2822 
  2823 * New primrec package.  Specification syntax conforms in style to
  2824 definition/function/....  No separate induction rule is provided.  The
  2825 "primrec" command distinguishes old-style and new-style specifications
  2826 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2827 When adjusting theories, beware: constants stemming from new-style
  2828 primrec specifications have authentic syntax.
  2829 
  2830 * Metis prover is now an order of magnitude faster, and also works
  2831 with multithreading.
  2832 
  2833 * Metis: the maximum number of clauses that can be produced from a
  2834 theorem is now given by the attribute max_clauses.  Theorems that
  2835 exceed this number are ignored, with a warning printed.
  2836 
  2837 * Sledgehammer no longer produces structured proofs by default. To
  2838 enable, declare [[sledgehammer_full = true]].  Attributes
  2839 reconstruction_modulus, reconstruction_sorts renamed
  2840 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2841 
  2842 * Method "induct_scheme" derives user-specified induction rules
  2843 from well-founded induction and completeness of patterns. This factors
  2844 out some operations that are done internally by the function package
  2845 and makes them available separately.  See
  2846 src/HOL/ex/Induction_Scheme.thy for examples.
  2847 
  2848 * More flexible generation of measure functions for termination
  2849 proofs: Measure functions can be declared by proving a rule of the
  2850 form "is_measure f" and giving it the [measure_function] attribute.
  2851 The "is_measure" predicate is logically meaningless (always true), and
  2852 just guides the heuristic.  To find suitable measure functions, the
  2853 termination prover sets up the goal "is_measure ?f" of the appropriate
  2854 type and generates all solutions by prolog-style backwards proof using
  2855 the declared rules.
  2856 
  2857 This setup also deals with rules like 
  2858 
  2859   "is_measure f ==> is_measure (list_size f)"
  2860 
  2861 which accommodates nested datatypes that recurse through lists.
  2862 Similar rules are predeclared for products and option types.
  2863 
  2864 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2865 
  2866   INCOMPATIBILITIES:
  2867 
  2868   - Definitions of overloaded constants on sets have to be replaced by
  2869     definitions on => and bool.
  2870 
  2871   - Some definitions of overloaded operators on sets can now be proved
  2872     using the definitions of the operators on => and bool.  Therefore,
  2873     the following theorems have been renamed:
  2874 
  2875       subset_def   -> subset_eq
  2876       psubset_def  -> psubset_eq
  2877       set_diff_def -> set_diff_eq
  2878       Compl_def    -> Compl_eq
  2879       Sup_set_def  -> Sup_set_eq
  2880       Inf_set_def  -> Inf_set_eq
  2881       sup_set_def  -> sup_set_eq
  2882       inf_set_def  -> inf_set_eq
  2883 
  2884   - Due to the incompleteness of the HO unification algorithm, some
  2885     rules such as subst may require manual instantiation, if some of
  2886     the unknowns in the rule is a set.
  2887 
  2888   - Higher order unification and forward proofs:
  2889     The proof pattern
  2890 
  2891       have "P (S::'a set)" <...>
  2892       then have "EX S. P S" ..
  2893 
  2894     no longer works (due to the incompleteness of the HO unification
  2895     algorithm) and must be replaced by the pattern
  2896 
  2897       have "EX S. P S"
  2898       proof
  2899         show "P S" <...>
  2900       qed
  2901 
  2902   - Calculational reasoning with subst (or similar rules):
  2903     The proof pattern
  2904 
  2905       have "P (S::'a set)" <...>
  2906       also have "S = T" <...>
  2907       finally have "P T" .
  2908 
  2909     no longer works (for similar reasons as the previous example) and
  2910     must be replaced by something like
  2911 
  2912       have "P (S::'a set)" <...>
  2913       moreover have "S = T" <...>
  2914       ultimately have "P T" by simp
  2915 
  2916   - Tactics or packages written in ML code:
  2917     Code performing pattern matching on types via
  2918 
  2919       Type ("set", [T]) => ...
  2920 
  2921     must be rewritten. Moreover, functions like strip_type or
  2922     binder_types no longer return the right value when applied to a
  2923     type of the form
  2924 
  2925       T1 => ... => Tn => U => bool
  2926 
  2927     rather than
  2928 
  2929       T1 => ... => Tn => U set
  2930 
  2931 * Merged theories Wellfounded_Recursion, Accessible_Part and
  2932 Wellfounded_Relations to theory Wellfounded.
  2933 
  2934 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  2935 
  2936 * Class finite no longer treats UNIV as class parameter.  Use class
  2937 enum from theory Library/Enum instead to achieve a similar effect.
  2938 INCOMPATIBILITY.
  2939 
  2940 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  2941 and "Cons".  INCOMPATIBILITY.
  2942 
  2943 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  2944 Potential INCOMPATIBILITY.
  2945 
  2946 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  2947 injective_fst_snd removed, use split_eta and prod_eqI instead.
  2948 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  2949 
  2950 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  2951 the same name in theory Orderings:
  2952 
  2953   less_trans
  2954   less_linear
  2955   le_imp_less_or_eq
  2956   le_less_trans
  2957   less_le_trans
  2958   less_not_sym
  2959   less_asym
  2960 
  2961 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  2962 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  2963 and different variable names.
  2964 
  2965 * Library/Option_ord.thy: Canonical order on option type.
  2966 
  2967 * Library/RBT.thy: Red-black trees, an efficient implementation of
  2968 finite maps.
  2969 
  2970 * Library/Countable.thy: Type class for countable types.
  2971 
  2972 * Theory Int: The representation of numerals has changed.  The infix
  2973 operator BIT and the bit datatype with constructors B0 and B1 have
  2974 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  2975 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  2976 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  2977 accordingly.
  2978 
  2979 * Theory Nat: definition of <= and < on natural numbers no longer
  2980 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  2981 le_def and less_def have disappeared.  Consider lemmas not_less
  2982 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  2983 
  2984 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  2985 (whose purpose mainly is for various fold_set functionals) have been
  2986 abandoned in favor of the existing algebraic classes
  2987 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  2988 lower_semilattice (resp. upper_semilattice) and linorder.
  2989 INCOMPATIBILITY.
  2990 
  2991 * Theory Transitive_Closure: induct and cases rules now declare proper
  2992 case_names ("base" and "step").  INCOMPATIBILITY.
  2993 
  2994 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  2995 lattices.  The form set-specific version is available as
  2996 Inductive.lfp_ordinal_induct_set.
  2997 
  2998 * Renamed theorems "power.simps" to "power_int.simps".
  2999 INCOMPATIBILITY.
  3000 
  3001 * Class semiring_div provides basic abstract properties of semirings
  3002 with division and modulo operations.  Subsumes former class dvd_mod.
  3003 
  3004 * Merged theories IntDef, Numeral and IntArith into unified theory
  3005 Int.  INCOMPATIBILITY.
  3006 
  3007 * Theory Library/Code_Index: type "index" now represents natural
  3008 numbers rather than integers.  INCOMPATIBILITY.
  3009 
  3010 * New class "uminus" with operation "uminus" (split of from class
  3011 "minus" which now only has operation "minus", binary).
  3012 INCOMPATIBILITY.
  3013 
  3014 * Constants "card", "internal_split", "option_map" now with authentic
  3015 syntax.  INCOMPATIBILITY.
  3016 
  3017 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3018 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3019 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3020 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3021 Sup_set_def, le_def, less_def, option_map_def now with object
  3022 equality.  INCOMPATIBILITY.
  3023 
  3024 * Records. Removed K_record, and replaced it by pure lambda term
  3025 %x. c. The simplifier setup is now more robust against eta expansion.
  3026 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3027 
  3028 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3029 
  3030 * Library/ListVector: new theory of arithmetic vector operations.
  3031 
  3032 * Library/Order_Relation: new theory of various orderings as sets of
  3033 pairs.  Defines preorders, partial orders, linear orders and
  3034 well-orders on sets and on types.
  3035 
  3036 
  3037 *** ZF ***
  3038 
  3039 * Renamed some theories to allow to loading both ZF and HOL in the
  3040 same session:
  3041 
  3042   Datatype  -> Datatype_ZF
  3043   Inductive -> Inductive_ZF
  3044   Int       -> Int_ZF
  3045   IntDiv    -> IntDiv_ZF
  3046   Nat       -> Nat_ZF
  3047   List      -> List_ZF
  3048   Main      -> Main_ZF
  3049 
  3050 INCOMPATIBILITY: ZF theories that import individual theories below
  3051 Main might need to be adapted.  Regular theory Main is still
  3052 available, as trivial extension of Main_ZF.
  3053 
  3054 
  3055 *** ML ***
  3056 
  3057 * ML within Isar: antiquotation @{const name} or @{const
  3058 name(typargs)} produces statically-checked Const term.
  3059 
  3060 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3061 (of the same name).  Removed obsolete print command.
  3062 
  3063 * Removed obsolete "use_legacy_bindings" function.
  3064 
  3065 * The ``print mode'' is now a thread-local value derived from a global
  3066 template (the former print_mode reference), thus access becomes
  3067 non-critical.  The global print_mode reference is for session
  3068 management only; user-code should use print_mode_value,
  3069 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3070 
  3071 * Functions system/system_out provide a robust way to invoke external
  3072 shell commands, with propagation of interrupts (requires Poly/ML
  3073 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3074 
  3075 
  3076 *** System ***
  3077 
  3078 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3079 in accordance with Proof General 3.7, which prefers GNU emacs.
  3080 
  3081 * isatool tty runs Isabelle process with plain tty interaction;
  3082 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3083 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3084 
  3085 * isatool browser now works with Cygwin as well, using general
  3086 "javapath" function defined in Isabelle process environment.
  3087 
  3088 * YXML notation provides a simple and efficient alternative to
  3089 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3090 isatool yxml as described in the Isabelle system manual.
  3091 
  3092 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3093 provides general wrapper for managing an Isabelle process in a robust
  3094 fashion, with ``cooked'' output from stdin/stderr.
  3095 
  3096 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3097 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3098 
  3099 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3100 way of changing the user's settings is via
  3101 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3102 script.
  3103 
  3104 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3105 cores of the underlying machine, which is a good starting point for
  3106 optimal performance tuning.  The corresponding usedir option -M allows
  3107 "max" as an alias for "0".  WARNING: does not work on certain versions
  3108 of Mac OS (with Poly/ML 5.1).
  3109 
  3110 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3111 adverse effect of Isabelle flooding interactive front-ends (notably
  3112 ProofGeneral / XEmacs).
  3113 
  3114 
  3115 
  3116 New in Isabelle2007 (November 2007)
  3117 -----------------------------------
  3118 
  3119 *** General ***
  3120 
  3121 * More uniform information about legacy features, notably a
  3122 warning/error of "Legacy feature: ...", depending on the state of the
  3123 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3124 legacy features will disappear eventually.
  3125 
  3126 * Theory syntax: the header format ``theory A = B + C:'' has been
  3127 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3128 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3129 
  3130 * Theory syntax: the old non-Isar theory file format has been
  3131 discontinued altogether.  Note that ML proof scripts may still be used
  3132 with Isar theories; migration is usually quite simple with the ML
  3133 function use_legacy_bindings.  INCOMPATIBILITY.
  3134 
  3135 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3136 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3137 quotes.
  3138 
  3139 * Theory loader: be more serious about observing the static theory
  3140 header specifications (including optional directories), but not the
  3141 accidental file locations of previously successful loads.  The strict
  3142 update policy of former update_thy is now already performed by
  3143 use_thy, so the former has been removed; use_thys updates several
  3144 theories simultaneously, just as 'imports' within a theory header
  3145 specification, but without merging the results.  Potential
  3146 INCOMPATIBILITY: may need to refine theory headers and commands
  3147 ROOT.ML which depend on load order.
  3148 
  3149 * Theory loader: optional support for content-based file
  3150 identification, instead of the traditional scheme of full physical
  3151 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3152 (cf. the system manual).  The new scheme allows to work with
  3153 non-finished theories in persistent session images, such that source
  3154 files may be moved later on without requiring reloads.
  3155 
  3156 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3157 file (with the same base name as the theory) are considered a legacy
  3158 feature, which will disappear eventually. Even now, the theory loader
  3159 no longer maintains dependencies on such files.
  3160 
  3161 * Syntax: the scope for resolving ambiguities via type-inference is
  3162 now limited to individual terms, instead of whole simultaneous
  3163 specifications as before. This greatly reduces the complexity of the
  3164 syntax module and improves flexibility by separating parsing and
  3165 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3166 'fixes' etc.) are required in rare situations.
  3167 
  3168 * Syntax: constants introduced by new-style packages ('definition',
  3169 'abbreviation' etc.) are passed through the syntax module in
  3170 ``authentic mode''. This means that associated mixfix annotations
  3171 really stick to such constants, independently of potential name space
  3172 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3173 trees are represented slightly differently, may need to adapt syntax
  3174 translations accordingly. Use CONST marker in 'translations' and
  3175 @{const_syntax} antiquotation in 'parse_translation' etc.
  3176 
  3177 * Legacy goal package: reduced interface to the bare minimum required
  3178 to keep existing proof scripts running.  Most other user-level
  3179 functions are now part of the OldGoals structure, which is *not* open
  3180 by default (consider isatool expandshort before open OldGoals).
  3181 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3182 these tend to cause confusion about the actual goal (!) context being
  3183 used here, which is not necessarily the same as the_context().
  3184 
  3185 * Command 'find_theorems': supports "*" wild-card in "name:"
  3186 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3187 support a specific search form (see ProofGeneral/CHANGES).
  3188 
  3189 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3190 by default, which means that "prems" (and also "fixed variables") are
  3191 suppressed from proof state output.  Note that the ProofGeneral
  3192 settings mechanism allows to change and save options persistently, but
  3193 older versions of Isabelle will fail to start up if a negative prems
  3194 limit is imposed.
  3195 
  3196 * Local theory targets may be specified by non-nested blocks of
  3197 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3198 contain definitions, theorems etc., including any derived mechanism
  3199 that has been implemented on top of these primitives.  This concept
  3200 generalizes the existing ``theorem (in ...)'' towards more versatility
  3201 and scalability.
  3202 
  3203 * Proof General interface: proper undo of final 'end' command;
  3204 discontinued Isabelle/classic mode (ML proof scripts).
  3205 
  3206 
  3207 *** Document preparation ***
  3208 
  3209 * Added antiquotation @{theory name} which prints the given name,
  3210 after checking that it refers to a valid ancestor theory in the
  3211 current context.
  3212 
  3213 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3214 check the given source text as ML type/structure, printing verbatim.
  3215 
  3216 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3217 "c args == rhs" given in the current context.  (Any number of
  3218 arguments may be given on the LHS.)
  3219 
  3220 
  3221 *** Pure ***
  3222 
  3223 * The 'class' package offers a combination of axclass and locale to
  3224 achieve Haskell-like type classes in Isabelle.  Definitions and
  3225 theorems within a class context produce both relative results (with
  3226 implicit parameters according to the locale context), and polymorphic
  3227 constants with qualified polymorphism (according to the class
  3228 context).  Within the body context of a 'class' target, a separate
  3229 syntax layer ("user space type system") takes care of converting
  3230 between global polymorphic consts and internal locale representation.
  3231 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3232 "isatool doc classes" provides a tutorial.
  3233 
  3234 * Generic code generator framework allows to generate executable
  3235 code for ML and Haskell (including Isabelle classes).  A short usage
  3236 sketch:
  3237 
  3238     internal compilation:
  3239         export_code <list of constants (term syntax)> in SML
  3240     writing SML code to a file:
  3241         export_code <list of constants (term syntax)> in SML <filename>
  3242     writing OCaml code to a file:
  3243         export_code <list of constants (term syntax)> in OCaml <filename>
  3244     writing Haskell code to a bunch of files:
  3245         export_code <list of constants (term syntax)> in Haskell <filename>
  3246 
  3247     evaluating closed propositions to True/False using code generation:
  3248         method ``eval''
  3249 
  3250 Reasonable default setup of framework in HOL.
  3251 
  3252 Theorem attributs for selecting and transforming function equations theorems:
  3253 
  3254     [code fun]:        select a theorem as function equation for a specific constant
  3255     [code fun del]:    deselect a theorem as function equation for a specific constant
  3256     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3257     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3258 
  3259 User-defined serializations (target in {SML, OCaml, Haskell}):
  3260 
  3261     code_const <and-list of constants (term syntax)>
  3262       {(target) <and-list of const target syntax>}+
  3263 
  3264     code_type <and-list of type constructors>
  3265       {(target) <and-list of type target syntax>}+
  3266 
  3267     code_instance <and-list of instances>
  3268       {(target)}+
  3269         where instance ::= <type constructor> :: <class>
  3270 
  3271     code_class <and_list of classes>
  3272       {(target) <and-list of class target syntax>}+
  3273         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3274 
  3275 code_instance and code_class only are effective to target Haskell.
  3276 
  3277 For example usage see src/HOL/ex/Codegenerator.thy and
  3278 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3279 generation from Isabelle/HOL theories is available via "isatool doc
  3280 codegen".
  3281 
  3282 * Code generator: consts in 'consts_code' Isar commands are now
  3283 referred to by usual term syntax (including optional type
  3284 annotations).
  3285 
  3286 * Command 'no_translations' removes translation rules from theory
  3287 syntax.
  3288 
  3289 * Overloaded definitions are now actually checked for acyclic
  3290 dependencies.  The overloading scheme is slightly more general than
  3291 that of Haskell98, although Isabelle does not demand an exact
  3292 correspondence to type class and instance declarations.
  3293 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3294 exotic versions of overloading -- at the discretion of the user!
  3295 
  3296 Polymorphic constants are represented via type arguments, i.e. the
  3297 instantiation that matches an instance against the most general
  3298 declaration given in the signature.  For example, with the declaration
  3299 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3300 as c(nat).  Overloading is essentially simultaneous structural
  3301 recursion over such type arguments.  Incomplete specification patterns
  3302 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3303 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3304 Command 'print_theory' outputs the normalized system of recursive
  3305 equations, see section "definitions".
  3306 
  3307 * Configuration options are maintained within the theory or proof
  3308 context (with name and type bool/int/string), providing a very simple
  3309 interface to a poor-man's version of general context data.  Tools may
  3310 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3311 these values using Config.get etc.  Users may change options via an
  3312 associated attribute of the same name.  This form of context
  3313 declaration works particularly well with commands 'declare' or
  3314 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3315 very easy to avoid global references, which would not observe Isar
  3316 toplevel undo/redo and fail to work with multithreading.
  3317 
  3318 Various global ML references of Pure and HOL have been turned into
  3319 configuration options:
  3320 
  3321   Unify.search_bound		unify_search_bound
  3322   Unify.trace_bound		unify_trace_bound
  3323   Unify.trace_simp		unify_trace_simp
  3324   Unify.trace_types		unify_trace_types
  3325   Simplifier.simp_depth_limit	simp_depth_limit
  3326   Blast.depth_limit		blast_depth_limit
  3327   DatatypeProp.dtK		datatype_distinctness_limit
  3328   fast_arith_neq_limit  	fast_arith_neq_limit
  3329   fast_arith_split_limit	fast_arith_split_limit
  3330 
  3331 * Named collections of theorems may be easily installed as context
  3332 data using the functor NamedThmsFun (see also
  3333 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3334 attributes; there is also a toplevel print command.  This facility is
  3335 just a common case of general context data, which is the preferred way
  3336 for anything more complex than just a list of facts in canonical
  3337 order.
  3338 
  3339 * Isar: command 'declaration' augments a local theory by generic
  3340 declaration functions written in ML.  This enables arbitrary content
  3341 being added to the context, depending on a morphism that tells the
  3342 difference of the original declaration context wrt. the application
  3343 context encountered later on.
  3344 
  3345 * Isar: proper interfaces for simplification procedures.  Command
  3346 'simproc_setup' declares named simprocs (with match patterns, and body
  3347 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3348 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3349 
  3350 * Isar: an extra pair of brackets around attribute declarations
  3351 abbreviates a theorem reference involving an internal dummy fact,
  3352 which will be ignored later --- only the effect of the attribute on
  3353 the background context will persist.  This form of in-place
  3354 declarations is particularly useful with commands like 'declare' and
  3355 'using', for example ``have A using [[simproc a]] by simp''.
  3356 
  3357 * Isar: method "assumption" (and implicit closing of subproofs) now
  3358 takes simple non-atomic goal assumptions into account: after applying
  3359 an assumption as a rule the resulting subgoals are solved by atomic
  3360 assumption steps.  This is particularly useful to finish 'obtain'
  3361 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3362 without referring to the original premise "!!x. P x ==> thesis" in the
  3363 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3364 more permissive.
  3365 
  3366 * Isar: implicit use of prems from the Isar proof context is
  3367 considered a legacy feature.  Common applications like ``have A .''
  3368 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3369 referencing facts explicitly here improves readability and
  3370 maintainability of proof texts.
  3371 
  3372 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3373 the obtained context from the course of reasoning!  For example:
  3374 
  3375   assume "EX x y. A x & B y"   -- "any previous fact"
  3376   then guess x and y by clarify
  3377 
  3378 This technique is potentially adventurous, depending on the facts and
  3379 proof tools being involved here.
  3380 
  3381 * Isar: known facts from the proof context may be specified as literal
  3382 propositions, using ASCII back-quote syntax.  This works wherever
  3383 named facts used to be allowed so far, in proof commands, proof
  3384 methods, attributes etc.  Literal facts are retrieved from the context
  3385 according to unification of type and term parameters.  For example,
  3386 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3387 theorems in the current context, then these are valid literal facts:
  3388 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3389 
  3390 There is also a proof method "fact" which does the same composition
  3391 for explicit goal states, e.g. the following proof texts coincide with
  3392 certain special cases of literal facts:
  3393 
  3394   have "A" by fact                 ==  note `A`
  3395   have "A ==> B" by fact           ==  note `A ==> B`
  3396   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3397   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3398 
  3399 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3400 outer syntax.  Thus symbolic identifiers may be used without
  3401 additional white space in declarations like this: ``assume *: A''.
  3402 
  3403 * Isar: 'print_facts' prints all local facts of the current context,
  3404 both named and unnamed ones.
  3405 
  3406 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3407 
  3408   def x == "t" and y == "u"
  3409 
  3410 * Isar: added command 'unfolding', which is structurally similar to
  3411 'using', but affects both the goal state and facts by unfolding given
  3412 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3413 'unfolded' attribute may be replaced by first-class proof text.
  3414 
  3415 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3416 and command 'unfolding' now all support object-level equalities
  3417 (potentially conditional).  The underlying notion of rewrite rule is
  3418 analogous to the 'rule_format' attribute, but *not* that of the
  3419 Simplifier (which is usually more generous).
  3420 
  3421 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3422 premises of a theorem by n. Useful in conjunction with drule.
  3423 
  3424 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3425 method expression within a sandbox consisting of the first N
  3426 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3427 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3428 simplifies all new goals that emerge from applying rule foo to the
  3429 originally first one.
  3430 
  3431 * Isar: schematic goals are no longer restricted to higher-order
  3432 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3433 expected.
  3434 
  3435 * Isar: the conclusion of a long theorem statement is now either
  3436 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3437 (essentially a disjunction of cases with local parameters and
  3438 assumptions).  The latter allows to express general elimination rules
  3439 adequately; in this notation common elimination rules look like this:
  3440 
  3441   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3442     assumes "EX x. P x"
  3443     obtains x where "P x"
  3444 
  3445   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3446     assumes "A & B"
  3447     obtains A and B
  3448 
  3449   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3450     assumes "A | B"
  3451     obtains
  3452       A
  3453     | B
  3454 
  3455 The subsequent classical rules even refer to the formal "thesis"
  3456 explicitly:
  3457 
  3458   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3459     obtains "~ thesis"
  3460 
  3461   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3462     obtains "thesis ==> something"
  3463 
  3464 The actual proof of an 'obtains' statement is analogous to that of the
  3465 Isar proof element 'obtain', only that there may be several cases.
  3466 Optional case names may be specified in parentheses; these will be
  3467 available both in the present proof and as annotations in the
  3468 resulting rule, for later use with the 'cases' method (cf. attribute
  3469 case_names).
  3470 
  3471 * Isar: the assumptions of a long theorem statement are available as
  3472 "assms" fact in the proof context.  This is more appropriate than the
  3473 (historical) "prems", which refers to all assumptions of the current
  3474 context, including those from the target locale, proof body etc.
  3475 
  3476 * Isar: 'print_statement' prints theorems from the current theory or
  3477 proof context in long statement form, according to the syntax of a
  3478 top-level lemma.
  3479 
  3480 * Isar: 'obtain' takes an optional case name for the local context
  3481 introduction rule (default "that").
  3482 
  3483 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3484 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3485 to occur.
  3486 
  3487 * Pure: syntax "CONST name" produces a fully internalized constant
  3488 according to the current context.  This is particularly useful for
  3489 syntax translations that should refer to internal constant
  3490 representations independently of name spaces.
  3491 
  3492 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3493 instead of "FOO ". This allows multiple binder declarations to coexist
  3494 in the same context.  INCOMPATIBILITY.
  3495 
  3496 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3497 primitive that also works in a locale context (both for constants and
  3498 fixed variables). Type declaration and internal syntactic representation
  3499 of given constants retrieved from the context. Likewise, the
  3500 'no_notation' command allows to remove given syntax annotations from the
  3501 current context.
  3502 
  3503 * Isar/locales: new derived specification elements 'axiomatization',
  3504 'definition', 'abbreviation', which support type-inference, admit
  3505 object-level specifications (equality, equivalence).  See also the
  3506 isar-ref manual.  Examples:
  3507 
  3508   axiomatization
  3509     eq  (infix "===" 50) where
  3510     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3511 
  3512   definition "f x y = x + y + 1"
  3513   definition g where "g x = f x x"
  3514 
  3515   abbreviation
  3516     neq  (infix "=!=" 50) where
  3517     "x =!= y == ~ (x === y)"
  3518 
  3519 These specifications may be also used in a locale context.  Then the
  3520 constants being introduced depend on certain fixed parameters, and the
  3521 constant name is qualified by the locale base name.  An internal
  3522 abbreviation takes care for convenient input and output, making the
  3523 parameters implicit and using the original short name.  See also
  3524 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3525 entities from a monomorphic theory.
  3526 
  3527 Presently, abbreviations are only available 'in' a target locale, but
  3528 not inherited by general import expressions.  Also note that
  3529 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3530 'translations' in common applications.  The "no_abbrevs" print mode
  3531 prevents folding of abbreviations in term output.
  3532 
  3533 Concrete syntax is attached to specified constants in internal form,
  3534 independently of name spaces.  The parse tree representation is
  3535 slightly different -- use 'notation' instead of raw 'syntax', and
  3536 'translations' with explicit "CONST" markup to accommodate this.
  3537 
  3538 * Pure/Isar: unified syntax for new-style specification mechanisms
  3539 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3540 full type inference and dummy patterns ("_").  For example:
  3541 
  3542   definition "K x _ = x"
  3543 
  3544   inductive conj for A B
  3545   where "A ==> B ==> conj A B"
  3546 
  3547 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3548 the current context.  Print mode "no_abbrevs" prevents inversion of
  3549 abbreviations on output.
  3550 
  3551 * Isar/locales: improved parameter handling: use of locales "var" and
  3552 "struct" no longer necessary; - parameter renamings are no longer
  3553 required to be injective.  For example, this allows to define
  3554 endomorphisms as locale endom = homom mult mult h.
  3555 
  3556 * Isar/locales: changed the way locales with predicates are defined.
  3557 Instead of accumulating the specification, the imported expression is
  3558 now an interpretation.  INCOMPATIBILITY: different normal form of
  3559 locale expressions.  In particular, in interpretations of locales with
  3560 predicates, goals repesenting already interpreted fragments are not
  3561 removed automatically.  Use methods `intro_locales' and
  3562 `unfold_locales'; see below.
  3563 
  3564 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3565 provide backward reasoning on locales predicates.  The methods are
  3566 aware of interpretations and discharge corresponding goals.
  3567 `intro_locales' is less aggressive then `unfold_locales' and does not
  3568 unfold predicates to assumptions.
  3569 
  3570 * Isar/locales: the order in which locale fragments are accumulated
  3571 has changed.  This enables to override declarations from fragments due
  3572 to interpretations -- for example, unwanted simp rules.
  3573 
  3574 * Isar/locales: interpretation in theories and proof contexts has been
  3575 extended.  One may now specify (and prove) equations, which are
  3576 unfolded in interpreted theorems.  This is useful for replacing
  3577 defined concepts (constants depending on locale parameters) by
  3578 concepts already existing in the target context.  Example:
  3579 
  3580   interpretation partial_order ["op <= :: [int, int] => bool"]
  3581     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3582 
  3583 Typically, the constant `partial_order.less' is created by a
  3584 definition specification element in the context of locale
  3585 partial_order.
  3586 
  3587 * Method "induct": improved internal context management to support
  3588 local fixes and defines on-the-fly. Thus explicit meta-level
  3589 connectives !!  and ==> are rarely required anymore in inductive goals
  3590 (using object-logic connectives for this purpose has been long
  3591 obsolete anyway). Common proof patterns are explained in
  3592 src/HOL/Induct/Common_Patterns.thy, see also
  3593 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3594 examples.
  3595 
  3596 * Method "induct": improved handling of simultaneous goals. Instead of
  3597 introducing object-level conjunction, the statement is now split into
  3598 several conclusions, while the corresponding symbolic cases are nested
  3599 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3600 see src/HOL/Induct/Common_Patterns.thy, for example.
  3601 
  3602 * Method "induct": mutual induction rules are now specified as a list
  3603 of rule sharing the same induction cases. HOL packages usually provide
  3604 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3605 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3606 mutual induction rules differently, i.e. like this:
  3607 
  3608   (induct rule: foo_bar.inducts)
  3609   (induct set: foo bar)
  3610   (induct pred: foo bar)
  3611   (induct type: foo bar)
  3612 
  3613 The ML function ProjectRule.projections turns old-style rules into the
  3614 new format.
  3615 
  3616 * Method "coinduct": dual of induction, see
  3617 src/HOL/Library/Coinductive_List.thy for various examples.
  3618 
  3619 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3620 considered a legacy feature.
  3621 
  3622 * Attribute "symmetric" produces result with standardized schematic
  3623 variables (index 0).  Potential INCOMPATIBILITY.
  3624 
  3625 * Simplifier: by default the simplifier trace only shows top level
  3626 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3627 default. Thus there is less danger of being flooded by the trace. The
  3628 trace indicates where parts have been suppressed.
  3629   
  3630 * Provers/classical: removed obsolete classical version of elim_format
  3631 attribute; classical elim/dest rules are now treated uniformly when
  3632 manipulating the claset.
  3633 
  3634 * Provers/classical: stricter checks to ensure that supplied intro,
  3635 dest and elim rules are well-formed; dest and elim rules must have at
  3636 least one premise.
  3637 
  3638 * Provers/classical: attributes dest/elim/intro take an optional
  3639 weight argument for the rule (just as the Pure versions).  Weights are
  3640 ignored by automated tools, but determine the search order of single
  3641 rule steps.
  3642 
  3643 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3644 where the body does not mention the bound variable.  Note that dummy
  3645 patterns implicitly depend on their context of bounds, which makes
  3646 "{_. _}" match any set comprehension as expected.  Potential
  3647 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3648 constant "_idtdummy" in the binding position.
  3649 
  3650 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3651 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3652 for example "A -> B" => "Pi A (%_. B)".
  3653 
  3654 * Pure: 'class_deps' command visualizes the subclass relation, using
  3655 the graph browser tool.
  3656 
  3657 * Pure: 'print_theory' now suppresses certain internal declarations by
  3658 default; use '!' option for full details.
  3659 
  3660 
  3661 *** HOL ***
  3662 
  3663 * Method "metis" proves goals by applying the Metis general-purpose
  3664 resolution prover (see also http://gilith.com/software/metis/).
  3665 Examples are in the directory MetisExamples.  WARNING: the
  3666 Isabelle/HOL-Metis integration does not yet work properly with
  3667 multi-threading.
  3668   
  3669 * Command 'sledgehammer' invokes external automatic theorem provers as
  3670 background processes.  It generates calls to the "metis" method if
  3671 successful. These can be pasted into the proof.  Users do not have to
  3672 wait for the automatic provers to return.  WARNING: does not really
  3673 work with multi-threading.
  3674 
  3675 * New "auto_quickcheck" feature tests outermost goal statements for
  3676 potential counter-examples.  Controlled by ML references
  3677 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3678 5000 milliseconds).  Fails silently if statements is outside of
  3679 executable fragment, or any other codgenerator problem occurs.
  3680 
  3681 * New constant "undefined" with axiom "undefined x = undefined".
  3682 
  3683 * Added class "HOL.eq", allowing for code generation with polymorphic
  3684 equality.
  3685 
  3686 * Some renaming of class constants due to canonical name prefixing in
  3687 the new 'class' package:
  3688 
  3689     HOL.abs ~> HOL.abs_class.abs
  3690     HOL.divide ~> HOL.divide_class.divide
  3691     0 ~> HOL.zero_class.zero
  3692     1 ~> HOL.one_class.one
  3693     op + ~> HOL.plus_class.plus
  3694     op - ~> HOL.minus_class.minus
  3695     uminus ~> HOL.minus_class.uminus
  3696     op * ~> HOL.times_class.times
  3697     op < ~> HOL.ord_class.less
  3698     op <= > HOL.ord_class.less_eq
  3699     Nat.power ~> Power.power_class.power
  3700     Nat.size ~> Nat.size_class.size
  3701     Numeral.number_of ~> Numeral.number_class.number_of
  3702     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3703     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3704     Orderings.min ~> Orderings.ord_class.min
  3705     Orderings.max ~> Orderings.ord_class.max
  3706     Divides.op div ~> Divides.div_class.div
  3707     Divides.op mod ~> Divides.div_class.mod
  3708     Divides.op dvd ~> Divides.div_class.dvd
  3709 
  3710 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3711 
  3712 a) User-defined constants using any of the names "plus", "minus",
  3713 "times", "less" or "less_eq". The standard syntax translations for
  3714 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3715 names.
  3716 
  3717 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3718 INCOMPATIBILITY: use more specific names.
  3719 
  3720 c) Permutative equations (e.g. "a + b = b + a")
  3721 Since the change of names also changes the order of terms, permutative
  3722 rewrite rules may get applied in a different order. Experience shows
  3723 that this is rarely the case (only two adaptions in the whole Isabelle
  3724 distribution).  INCOMPATIBILITY: rewrite proofs
  3725 
  3726 d) ML code directly refering to constant names
  3727 This in general only affects hand-written proof tactics, simprocs and
  3728 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3729 Consider using @{const_name} antiquotation.
  3730 
  3731 * New class "default" with associated constant "default".
  3732 
  3733 * Function "sgn" is now overloaded and available on int, real, complex
  3734 (and other numeric types), using class "sgn".  Two possible defs of
  3735 sgn are given as equational assumptions in the classes sgn_if and
  3736 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3737 INCOMPATIBILITY.
  3738 
  3739 * Locale "partial_order" now unified with class "order" (cf. theory
  3740 Orderings), added parameter "less".  INCOMPATIBILITY.
  3741 
  3742 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3743 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3744 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3745 
  3746 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3747 changed order of proof goals in instance proofs.
  3748 
  3749 * The transitivity reasoner for partial and linear orders is set up
  3750 for classes "order" and "linorder".  Instances of the reasoner are available
  3751 in all contexts importing or interpreting the corresponding locales.
  3752 Method "order" invokes the reasoner separately; the reasoner
  3753 is also integrated with the Simplifier as a solver.  Diagnostic
  3754 command 'print_orders' shows the available instances of the reasoner
  3755 in the current context.
  3756 
  3757 * Localized monotonicity predicate in theory "Orderings"; integrated
  3758 lemmas max_of_mono and min_of_mono with this predicate.
  3759 INCOMPATIBILITY.
  3760 
  3761 * Formulation of theorem "dense" changed slightly due to integration
  3762 with new class dense_linear_order.
  3763 
  3764 * Uniform lattice theory development in HOL.
  3765 
  3766     constants "meet" and "join" now named "inf" and "sup"
  3767     constant "Meet" now named "Inf"
  3768 
  3769     classes "meet_semilorder" and "join_semilorder" now named
  3770       "lower_semilattice" and "upper_semilattice"
  3771     class "lorder" now named "lattice"
  3772     class "comp_lat" now named "complete_lattice"
  3773 
  3774     Instantiation of lattice classes allows explicit definitions
  3775     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3776 
  3777   INCOMPATIBILITY.  Theorem renames:
  3778 
  3779     meet_left_le            ~> inf_le1
  3780     meet_right_le           ~> inf_le2
  3781     join_left_le            ~> sup_ge1
  3782     join_right_le           ~> sup_ge2
  3783     meet_join_le            ~> inf_sup_ord
  3784     le_meetI                ~> le_infI
  3785     join_leI                ~> le_supI
  3786     le_meet                 ~> le_inf_iff
  3787     le_join                 ~> ge_sup_conv
  3788     meet_idempotent         ~> inf_idem
  3789     join_idempotent         ~> sup_idem
  3790     meet_comm               ~> inf_commute
  3791     join_comm               ~> sup_commute
  3792     meet_leI1               ~> le_infI1
  3793     meet_leI2               ~> le_infI2
  3794     le_joinI1               ~> le_supI1
  3795     le_joinI2               ~> le_supI2
  3796     meet_assoc              ~> inf_assoc
  3797     join_assoc              ~> sup_assoc
  3798     meet_left_comm          ~> inf_left_commute
  3799     meet_left_idempotent    ~> inf_left_idem
  3800     join_left_comm          ~> sup_left_commute
  3801     join_left_idempotent    ~> sup_left_idem
  3802     meet_aci                ~> inf_aci
  3803     join_aci                ~> sup_aci
  3804     le_def_meet             ~> le_iff_inf
  3805     le_def_join             ~> le_iff_sup
  3806     join_absorp2            ~> sup_absorb2
  3807     join_absorp1            ~> sup_absorb1
  3808     meet_absorp1            ~> inf_absorb1
  3809     meet_absorp2            ~> inf_absorb2
  3810     meet_join_absorp        ~> inf_sup_absorb
  3811     join_meet_absorp        ~> sup_inf_absorb
  3812     distrib_join_le         ~> distrib_sup_le
  3813     distrib_meet_le         ~> distrib_inf_le
  3814 
  3815     add_meet_distrib_left   ~> add_inf_distrib_left
  3816     add_join_distrib_left   ~> add_sup_distrib_left
  3817     is_join_neg_meet        ~> is_join_neg_inf
  3818     is_meet_neg_join        ~> is_meet_neg_sup
  3819     add_meet_distrib_right  ~> add_inf_distrib_right
  3820     add_join_distrib_right  ~> add_sup_distrib_right
  3821     add_meet_join_distribs  ~> add_sup_inf_distribs
  3822     join_eq_neg_meet        ~> sup_eq_neg_inf
  3823     meet_eq_neg_join        ~> inf_eq_neg_sup
  3824     add_eq_meet_join        ~> add_eq_inf_sup
  3825     meet_0_imp_0            ~> inf_0_imp_0
  3826     join_0_imp_0            ~> sup_0_imp_0
  3827     meet_0_eq_0             ~> inf_0_eq_0
  3828     join_0_eq_0             ~> sup_0_eq_0
  3829     neg_meet_eq_join        ~> neg_inf_eq_sup
  3830     neg_join_eq_meet        ~> neg_sup_eq_inf
  3831     join_eq_if              ~> sup_eq_if
  3832 
  3833     mono_meet               ~> mono_inf
  3834     mono_join               ~> mono_sup
  3835     meet_bool_eq            ~> inf_bool_eq
  3836     join_bool_eq            ~> sup_bool_eq
  3837     meet_fun_eq             ~> inf_fun_eq
  3838     join_fun_eq             ~> sup_fun_eq
  3839     meet_set_eq             ~> inf_set_eq
  3840     join_set_eq             ~> sup_set_eq
  3841     meet1_iff               ~> inf1_iff
  3842     meet2_iff               ~> inf2_iff
  3843     meet1I                  ~> inf1I
  3844     meet2I                  ~> inf2I
  3845     meet1D1                 ~> inf1D1
  3846     meet2D1                 ~> inf2D1
  3847     meet1D2                 ~> inf1D2
  3848     meet2D2                 ~> inf2D2
  3849     meet1E                  ~> inf1E
  3850     meet2E                  ~> inf2E
  3851     join1_iff               ~> sup1_iff
  3852     join2_iff               ~> sup2_iff
  3853     join1I1                 ~> sup1I1
  3854     join2I1                 ~> sup2I1
  3855     join1I1                 ~> sup1I1
  3856     join2I2                 ~> sup1I2
  3857     join1CI                 ~> sup1CI
  3858     join2CI                 ~> sup2CI
  3859     join1E                  ~> sup1E
  3860     join2E                  ~> sup2E
  3861 
  3862     is_meet_Meet            ~> is_meet_Inf
  3863     Meet_bool_def           ~> Inf_bool_def
  3864     Meet_fun_def            ~> Inf_fun_def
  3865     Meet_greatest           ~> Inf_greatest
  3866     Meet_lower              ~> Inf_lower
  3867     Meet_set_def            ~> Inf_set_def
  3868 
  3869     Sup_def                 ~> Sup_Inf
  3870     Sup_bool_eq             ~> Sup_bool_def
  3871     Sup_fun_eq              ~> Sup_fun_def
  3872     Sup_set_eq              ~> Sup_set_def
  3873 
  3874     listsp_meetI            ~> listsp_infI
  3875     listsp_meet_eq          ~> listsp_inf_eq
  3876 
  3877     meet_min                ~> inf_min
  3878     join_max                ~> sup_max
  3879 
  3880 * Added syntactic class "size"; overloaded constant "size" now has
  3881 type "'a::size ==> bool"
  3882 
  3883 * Internal reorganisation of `size' of datatypes: size theorems
  3884 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3885 simplification rules by default!); theorems "prod.size" now named
  3886 "*.size".
  3887 
  3888 * Class "div" now inherits from class "times" rather than "type".
  3889 INCOMPATIBILITY.
  3890 
  3891 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  3892 Linorder etc.  have disappeared; operations defined in terms of
  3893 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  3894 
  3895 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  3896 
  3897 * HOL-Word: New extensive library and type for generic, fixed size
  3898 machine words, with arithemtic, bit-wise, shifting and rotating
  3899 operations, reflection into int, nat, and bool lists, automation for
  3900 linear arithmetic (by automatic reflection into nat or int), including
  3901 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  3902 arithmetic type classes, supporting automatic simplification of
  3903 numerals on all operations.
  3904 
  3905 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  3906 
  3907 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  3908 
  3909 * Code generator library theories:
  3910   - Code_Integer represents HOL integers by big integer literals in target
  3911     languages.
  3912   - Code_Char represents HOL characters by character literals in target
  3913     languages.
  3914   - Code_Char_chr like Code_Char, but also offers treatment of character
  3915     codes; includes Code_Integer.
  3916   - Executable_Set allows to generate code for finite sets using lists.
  3917   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  3918     denominator).
  3919   - Executable_Real implements a subset of real numbers, namly those
  3920     representable by rational numbers.
  3921   - Efficient_Nat implements natural numbers by integers, which in general will
  3922     result in higher efficency; pattern matching with 0/Suc is eliminated;
  3923     includes Code_Integer.
  3924   - Code_Index provides an additional datatype index which is mapped to
  3925     target-language built-in integers.
  3926   - Code_Message provides an additional datatype message_string which is isomorphic to
  3927     strings; messages are mapped to target-language strings.
  3928 
  3929 * New package for inductive predicates
  3930 
  3931   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  3932 
  3933     inductive
  3934       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3935       for z_1 :: U_1 and ... and z_n :: U_m
  3936     where
  3937       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3938     | ...
  3939 
  3940   with full support for type-inference, rather than
  3941 
  3942     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3943 
  3944     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3945     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3946 
  3947     inductive "s z_1 ... z_m"
  3948     intros
  3949       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3950       ...
  3951 
  3952   For backward compatibility, there is a wrapper allowing inductive
  3953   sets to be defined with the new package via
  3954 
  3955     inductive_set
  3956       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3957       for z_1 :: U_1 and ... and z_n :: U_m
  3958     where
  3959       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3960     | ...
  3961 
  3962   or
  3963 
  3964     inductive_set
  3965       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3966       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3967       for z_1 :: U_1 and ... and z_n :: U_m
  3968     where
  3969       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3970     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3971     | ...
  3972 
  3973   if the additional syntax "p ..." is required.
  3974 
  3975   Numerous examples can be found in the subdirectories src/HOL/Auth,
  3976   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  3977 
  3978   INCOMPATIBILITIES:
  3979 
  3980   - Since declaration and definition of inductive sets or predicates
  3981     is no longer separated, abbreviations involving the newly
  3982     introduced sets or predicates must be specified together with the
  3983     introduction rules after the 'where' keyword (see above), rather
  3984     than before the actual inductive definition.
  3985 
  3986   - The variables in induction and elimination rules are now
  3987     quantified in the order of their occurrence in the introduction
  3988     rules, rather than in alphabetical order. Since this may break
  3989     some proofs, these proofs either have to be repaired, e.g. by
  3990     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  3991     statements of the form
  3992 
  3993       case (rule_i a_i_1 ... a_i_{k_i})
  3994 
  3995     or the old order of quantification has to be restored by explicitly adding
  3996     meta-level quantifiers in the introduction rules, i.e.
  3997 
  3998       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  3999 
  4000   - The format of the elimination rules is now
  4001 
  4002       p z_1 ... z_m x_1 ... x_n ==>
  4003         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4004         ==> ... ==> P
  4005 
  4006     for predicates and
  4007 
  4008       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4009         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4010         ==> ... ==> P
  4011 
  4012     for sets rather than
  4013 
  4014       x : s z_1 ... z_m ==>
  4015         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4016         ==> ... ==> P
  4017 
  4018     This may require terms in goals to be expanded to n-tuples
  4019     (e.g. using case_tac or simplification with the split_paired_all
  4020     rule) before the above elimination rule is applicable.
  4021 
  4022   - The elimination or case analysis rules for (mutually) inductive
  4023     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4024     list of rules "p_1_..._p_k.elims" is no longer available.
  4025 
  4026 * New package "function"/"fun" for general recursive functions,
  4027 supporting mutual and nested recursion, definitions in local contexts,
  4028 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4029 for small examples, and the separate tutorial on the function
  4030 package. The old recdef "package" is still available as before, but
  4031 users are encouraged to use the new package.
  4032 
  4033 * Method "lexicographic_order" automatically synthesizes termination
  4034 relations as lexicographic combinations of size measures. 
  4035 
  4036 * Case-expressions allow arbitrary constructor-patterns (including
  4037 "_") and take their order into account, like in functional
  4038 programming.  Internally, this is translated into nested
  4039 case-expressions; missing cases are added and mapped to the predefined
  4040 constant "undefined". In complicated cases printing may no longer show
  4041 the original input but the internal form. Lambda-abstractions allow
  4042 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4043 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4044 variable.
  4045 
  4046 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4047 is an abbreviation for "of_nat :: nat => int". The simplification
  4048 rules for "of_nat" have been changed to work like "int" did
  4049 previously.  Potential INCOMPATIBILITY:
  4050   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4051   - of_nat_diff and of_nat_mult are no longer default simp rules
  4052 
  4053 * Method "algebra" solves polynomial equations over (semi)rings using
  4054 Groebner bases. The (semi)ring structure is defined by locales and the
  4055 tool setup depends on that generic context. Installing the method for
  4056 a specific type involves instantiating the locale and possibly adding
  4057 declarations for computation on the coefficients.  The method is
  4058 already instantiated for natural numbers and for the axiomatic class
  4059 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4060 CALCULEMUS 2007 for the general principles underlying this
  4061 architecture of context-aware proof-tools.
  4062 
  4063 * Method "ferrack" implements quantifier elimination over
  4064 special-purpose dense linear orders using locales (analogous to
  4065 "algebra"). The method is already installed for class
  4066 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4067 rat, etc.
  4068 
  4069 * Former constant "List.op @" now named "List.append".  Use ML
  4070 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4071 circumvent possible incompatibilities when working on ML level.
  4072 
  4073 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4074 
  4075 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4076 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4077 
  4078 * New syntax for Haskell-like list comprehension (input only), eg.
  4079 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4080 
  4081 * The special syntax for function "filter" has changed from [x :
  4082 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4083 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4084 
  4085 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4086 defined on nat only, as an abbreviation for [a..<Suc b]
  4087 INCOMPATIBILITY.
  4088 
  4089 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4090 
  4091 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4092 
  4093 * New lemma collection field_simps (an extension of ring_simps) for
  4094 manipulating (in)equations involving division. Multiplies with all
  4095 denominators that can be proved to be non-zero (in equations) or
  4096 positive/negative (in inequations).
  4097 
  4098 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4099 have been improved and renamed to ring_simps, group_simps and
  4100 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4101 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4102 
  4103 * Theory Library/Commutative_Ring: switched from recdef to function
  4104 package; constants add, mul, pow now curried.  Infix syntax for
  4105 algebraic operations.
  4106 
  4107 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4108 INCOMPATIBILITY.
  4109 
  4110 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4111 INCOMPATIBILITY.
  4112 
  4113 * HOL/records: generalised field-update to take a function on the
  4114 field rather than the new value: r(|A := x|) is translated to A_update
  4115 (K x) r The K-combinator that is internally used is called K_record.
  4116 INCOMPATIBILITY: Usage of the plain update functions has to be
  4117 adapted.
  4118  
  4119 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4120 * x = 0, which are required for a semiring.  Richer structures do not
  4121 inherit from semiring_0 anymore, because this property is a theorem
  4122 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4123 there is more to prove, but this is mostly trivial.
  4124 
  4125 * Class "recpower" is generalized to arbitrary monoids, not just
  4126 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4127 commutativity or semiring properties additionally.
  4128 
  4129 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4130 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4131 better use 'abbreviation'.
  4132 
  4133 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4134 
  4135 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4136 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4137 significant changes for setting up numeral syntax for types:
  4138   - New constants Numeral.pred and Numeral.succ instead
  4139       of former Numeral.bin_pred and Numeral.bin_succ.
  4140   - Use integer operations instead of bin_add, bin_mult and so on.
  4141   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4142   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4143 
  4144 See src/HOL/Integ/IntArith.thy for an example setup.
  4145 
  4146 * Command 'normal_form' computes the normal form of a term that may
  4147 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4148 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4149 heavy-duty computations because the functions are compiled to ML
  4150 first.  Correspondingly, a method "normalization" is provided.  See
  4151 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4152 
  4153 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4154 25 like -->); output depends on the "iff" print_mode, the default is
  4155 "A = B" (with priority 50).
  4156 
  4157 * Relations less (<) and less_eq (<=) are also available on type bool.
  4158 Modified syntax to disallow nesting without explicit parentheses,
  4159 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4160 INCOMPATIBILITY.
  4161 
  4162 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4163 
  4164 * Relation composition operator "op O" now has precedence 75 and binds
  4165 stronger than union and intersection. INCOMPATIBILITY.
  4166 
  4167 * The old set interval syntax "{m..n(}" (and relatives) has been
  4168 removed.  Use "{m..<n}" (and relatives) instead.
  4169 
  4170 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4171 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4172 ``declare [[simproc del: neq]]''.
  4173 
  4174 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4175 True/False.
  4176 
  4177 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4178 
  4179 * Theorem setsum_mult renamed to setsum_right_distrib.
  4180 
  4181 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4182 ``rule'' method.
  4183 
  4184 * Reimplemented methods "sat" and "satx", with several improvements:
  4185 goals no longer need to be stated as "<prems> ==> False", equivalences
  4186 (i.e. "=" on type bool) are handled, variable names of the form
  4187 "lit_<n>" are no longer reserved, significant speedup.
  4188 
  4189 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4190 zChaff is still supported as well.
  4191 
  4192 * 'inductive' and 'datatype': provide projections of mutual rules,
  4193 bundled as foo_bar.inducts;
  4194 
  4195 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4196 Library.
  4197 
  4198 * Library: moved theory Accessible_Part to main HOL.
  4199 
  4200 * Library: added theory Coinductive_List of potentially infinite lists
  4201 as greatest fixed-point.
  4202 
  4203 * Library: added theory AssocList which implements (finite) maps as
  4204 association lists.
  4205 
  4206 * Method "evaluation" solves goals (i.e. a boolean expression)
  4207 efficiently by compiling it to ML.  The goal is "proved" (via an
  4208 oracle) if it evaluates to True.
  4209 
  4210 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4211 also when invoked by the simplifier.  This results in the Simplifier
  4212 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4213 Configuration option fast_arith_split_limit=0 recovers the old
  4214 behavior.
  4215 
  4216 * Support for hex (0x20) and binary (0b1001) numerals.
  4217 
  4218 * New method: reify eqs (t), where eqs are equations for an
  4219 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4220 parameter, computes a term s::'b and a list xs::'a list and proves the
  4221 theorem I xs s = t. This is also known as reification or quoting. The
  4222 resulting theorem is applied to the subgoal to substitute t with I xs
  4223 s.  If t is omitted, the subgoal itself is reified.
  4224 
  4225 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4226 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4227 where f is supposed to be a computable function (in the sense of code
  4228 generattion). The method uses reify to compute s and xs as above then
  4229 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4230 r and finally gets the theorem t = r, which is again applied to the
  4231 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4232 
  4233 * Reflection: Automatic reification now handels binding, an example is
  4234 available in src/HOL/ex/ReflectionEx.thy
  4235 
  4236 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4237 command 'statespace' that is similar to 'record', but introduces an
  4238 abstract specification based on the locale infrastructure instead of
  4239 HOL types.  This leads to extra flexibility in composing state spaces,
  4240 in particular multiple inheritance and renaming of components.
  4241 
  4242 
  4243 *** HOL-Complex ***
  4244 
  4245 * Hyperreal: Functions root and sqrt are now defined on negative real
  4246 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4247 Nonnegativity side conditions have been removed from many lemmas, so
  4248 that more subgoals may now be solved by simplification; potential
  4249 INCOMPATIBILITY.
  4250 
  4251 * Real: new type classes formalize real normed vector spaces and
  4252 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4253 and norm :: 'a => real.
  4254 
  4255 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4256 reals into other types. The overloaded constant Reals :: 'a set is now
  4257 defined as range of_real; potential INCOMPATIBILITY.
  4258 
  4259 * Real: proper support for ML code generation, including 'quickcheck'.
  4260 Reals are implemented as arbitrary precision rationals.
  4261 
  4262 * Hyperreal: Several constants that previously worked only for the
  4263 reals have been generalized, so they now work over arbitrary vector
  4264 spaces. Type annotations may need to be added in some cases; potential
  4265 INCOMPATIBILITY.
  4266 
  4267   Infinitesimal  :: ('a::real_normed_vector) star set
  4268   HFinite        :: ('a::real_normed_vector) star set
  4269   HInfinite      :: ('a::real_normed_vector) star set
  4270   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4271   monad          :: ('a::real_normed_vector) star => 'a star set
  4272   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4273   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4274   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4275   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4276   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4277   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4278   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4279   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4280   sgn            :: 'a::real_normed_vector => 'a
  4281   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4282 
  4283 * Complex: Some complex-specific constants are now abbreviations for
  4284 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4285 hnorm.  Other constants have been entirely removed in favor of the
  4286 polymorphic versions (INCOMPATIBILITY):
  4287 
  4288   approx        <-- capprox
  4289   HFinite       <-- CFinite
  4290   HInfinite     <-- CInfinite
  4291   Infinitesimal <-- CInfinitesimal
  4292   monad         <-- cmonad
  4293   galaxy        <-- cgalaxy
  4294   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4295   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4296   (ns)deriv     <-- (ns)cderiv
  4297 
  4298 
  4299 *** HOL-Algebra ***
  4300 
  4301 * Formalisation of ideals and the quotient construction over rings.
  4302 
  4303 * Order and lattice theory no longer based on records.
  4304 INCOMPATIBILITY.
  4305 
  4306 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4307 greatest_closed.  INCOMPATIBILITY.
  4308 
  4309 * Method algebra is now set up via an attribute.  For examples see
  4310 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4311 of algebraic structures.
  4312 
  4313 * Renamed theory CRing to Ring.
  4314 
  4315 
  4316 *** HOL-Nominal ***
  4317 
  4318 * Substantial, yet incomplete support for nominal datatypes (binding
  4319 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4320 src/HOL/Nominal/Examples.  Prospective users should consult
  4321 http://isabelle.in.tum.de/nominal/
  4322 
  4323 
  4324 *** ML ***
  4325 
  4326 * ML basics: just one true type int, which coincides with IntInf.int
  4327 (even on SML/NJ).
  4328 
  4329 * ML within Isar: antiquotations allow to embed statically-checked
  4330 formal entities in the source, referring to the context available at
  4331 compile-time.  For example:
  4332 
  4333 ML {* @{sort "{zero,one}"} *}
  4334 ML {* @{typ "'a => 'b"} *}
  4335 ML {* @{term "%x. x"} *}
  4336 ML {* @{prop "x == y"} *}
  4337 ML {* @{ctyp "'a => 'b"} *}
  4338 ML {* @{cterm "%x. x"} *}
  4339 ML {* @{cprop "x == y"} *}
  4340 ML {* @{thm asm_rl} *}
  4341 ML {* @{thms asm_rl} *}
  4342 ML {* @{type_name c} *}
  4343 ML {* @{type_syntax c} *}
  4344 ML {* @{const_name c} *}
  4345 ML {* @{const_syntax c} *}
  4346 ML {* @{context} *}
  4347 ML {* @{theory} *}
  4348 ML {* @{theory Pure} *}
  4349 ML {* @{theory_ref} *}
  4350 ML {* @{theory_ref Pure} *}
  4351 ML {* @{simpset} *}
  4352 ML {* @{claset} *}
  4353 ML {* @{clasimpset} *}
  4354 
  4355 The same works for sources being ``used'' within an Isar context.
  4356 
  4357 * ML in Isar: improved error reporting; extra verbosity with
  4358 ML_Context.trace enabled.
  4359 
  4360 * Pure/General/table.ML: the join operations now works via exceptions
  4361 DUP/SAME instead of type option. This is simpler in simple cases, and
  4362 admits slightly more efficient complex applications.
  4363 
  4364 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4365 use Context.generic instead of just theory.
  4366 
  4367 * Pure: datatype Context.generic joins theory/Proof.context and
  4368 provides some facilities for code that works in either kind of
  4369 context, notably GenericDataFun for uniform theory and proof data.
  4370 
  4371 * Pure: simplified internal attribute type, which is now always
  4372 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4373 local (Proof.context) attributes have been discontinued, while
  4374 minimizing code duplication. Thm.rule_attribute and
  4375 Thm.declaration_attribute build canonical attributes; see also structure
  4376 Context for further operations on Context.generic, notably
  4377 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4378 declarations and definitions.
  4379 
  4380 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4381 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4382 init only required for impure data. INCOMPATIBILITY: empty really need
  4383 to be empty (no dependencies on theory content!)
  4384 
  4385 * Pure/kernel: consts certification ignores sort constraints given in
  4386 signature declarations. (This information is not relevant to the
  4387 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4388 potential INCOMPATIBILITY.
  4389 
  4390 * Pure: axiomatic type classes are now purely definitional, with
  4391 explicit proofs of class axioms and super class relations performed
  4392 internally. See Pure/axclass.ML for the main internal interfaces --
  4393 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4394 AxClass.axiomatize_class/classrel/arity supersede
  4395 Sign.add_classes/classrel/arities.
  4396 
  4397 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4398 global/local versions on theory vs. Proof.context have been
  4399 discontinued; Attrib.syntax and Method.syntax have been adapted
  4400 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4401 attributes, methods, etc.
  4402 
  4403 * Pure: several functions of signature "... -> theory -> theory * ..."
  4404 have been reoriented to "... -> theory -> ... * theory" in order to
  4405 allow natural usage in combination with the ||>, ||>>, |-> and
  4406 fold_map combinators.
  4407 
  4408 * Pure: official theorem names (closed derivations) and additional
  4409 comments (tags) are now strictly separate.  Name hints -- which are
  4410 maintained as tags -- may be attached any time without affecting the
  4411 derivation.
  4412 
  4413 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4414 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4415 achieve the old behaviour.
  4416 
  4417 * Pure: the "Goal" constant is now called "prop", supporting a
  4418 slightly more general idea of ``protecting'' meta-level rule
  4419 statements.
  4420 
  4421 * Pure: Logic.(un)varify only works in a global context, which is now
  4422 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4423 Logic.legacy_(un)varify as temporary workaround.
  4424 
  4425 * Pure: structure Name provides scalable operations for generating
  4426 internal variable names, notably Name.variants etc.  This replaces
  4427 some popular functions from term.ML:
  4428 
  4429   Term.variant		->  Name.variant
  4430   Term.variantlist	->  Name.variant_list
  4431   Term.invent_names	->  Name.invent_list
  4432 
  4433 Note that low-level renaming rarely occurs in new code -- operations
  4434 from structure Variable are used instead (see below).
  4435 
  4436 * Pure: structure Variable provides fundamental operations for proper
  4437 treatment of fixed/schematic variables in a context.  For example,
  4438 Variable.import introduces fixes for schematics of given facts and
  4439 Variable.export reverses the effect (up to renaming) -- this replaces
  4440 various freeze_thaw operations.
  4441 
  4442 * Pure: structure Goal provides simple interfaces for
  4443 init/conclude/finish and tactical prove operations (replacing former
  4444 Tactic.prove).  Goal.prove is the canonical way to prove results
  4445 within a given context; Goal.prove_global is a degraded version for
  4446 theory level goals, including a global Drule.standard.  Note that
  4447 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4448 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4449 in a locale context).
  4450 
  4451 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4452 and type checking (Syntax.check_term etc.), with common combinations
  4453 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4454 which are considered legacy and await removal.
  4455 
  4456 * Pure/Syntax: generic interfaces for type unchecking
  4457 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4458 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4459 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4460 available for convenience, but refer to the very same operations using
  4461 a mere theory instead of a full context.
  4462 
  4463 * Isar: simplified treatment of user-level errors, using exception
  4464 ERROR of string uniformly.  Function error now merely raises ERROR,
  4465 without any side effect on output channels.  The Isar toplevel takes
  4466 care of proper display of ERROR exceptions.  ML code may use plain
  4467 handle/can/try; cat_error may be used to concatenate errors like this:
  4468 
  4469   ... handle ERROR msg => cat_error msg "..."
  4470 
  4471 Toplevel ML code (run directly or through the Isar toplevel) may be
  4472 embedded into the Isar toplevel with exception display/debug like
  4473 this:
  4474 
  4475   Isar.toplevel (fn () => ...)
  4476 
  4477 INCOMPATIBILITY, removed special transform_error facilities, removed
  4478 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4479 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4480 -- use plain ERROR instead.
  4481 
  4482 * Isar: theory setup now has type (theory -> theory), instead of a
  4483 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4484 
  4485 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4486 ProofContext.debug/verbose flags.
  4487 
  4488 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4489 theory before entering a proof state.  Transactions now always see a
  4490 quasi-functional intermediate checkpoint, both in interactive and
  4491 batch mode.
  4492 
  4493 * Isar: simplified interfaces for outer syntax.  Renamed
  4494 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4495 OuterSyntax.add_parsers -- this functionality is now included in
  4496 OuterSyntax.command etc.  INCOMPATIBILITY.
  4497 
  4498 * Simplifier: the simpset of a running simplification process now
  4499 contains a proof context (cf. Simplifier.the_context), which is the
  4500 very context that the initial simpset has been retrieved from (by
  4501 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4502 (solver, looper etc.) may depend on arbitrary proof data.
  4503 
  4504 * Simplifier.inherit_context inherits the proof context (plus the
  4505 local bounds) of the current simplification process; any simproc
  4506 etc. that calls the Simplifier recursively should do this!  Removed
  4507 former Simplifier.inherit_bounds, which is already included here --
  4508 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4509 specify an explicit context using Simplifier.context/theory_context.
  4510 
  4511 * Simplifier/Classical Reasoner: more abstract interfaces
  4512 change_simpset/claset for modifying the simpset/claset reference of a
  4513 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4514 INCOMPATIBILITY.
  4515 
  4516 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4517 "Trueprop" etc.
  4518 
  4519 
  4520 *** System ***
  4521 
  4522 * settings: the default heap location within ISABELLE_HOME_USER now
  4523 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4524 Isabelle installations.
  4525 
  4526 * isabelle-process: option -S (secure mode) disables some critical
  4527 operations, notably runtime compilation and evaluation of ML source
  4528 code.
  4529 
  4530 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4531 
  4532 * Support for parallel execution, using native multicore support of
  4533 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4534 independent theories, according to the given theory header
  4535 specifications. The maximum number of worker threads is specified via
  4536 usedir option -M or the "max-threads" setting in Proof General. A
  4537 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4538 to 6 on a 8-core machine.  User-code needs to observe certain
  4539 guidelines for thread-safe programming, see appendix A in the Isar
  4540 Implementation manual.
  4541 
  4542 
  4543 
  4544 New in Isabelle2005 (October 2005)
  4545 ----------------------------------
  4546 
  4547 *** General ***
  4548 
  4549 * Theory headers: the new header syntax for Isar theories is
  4550 
  4551   theory <name>
  4552   imports <theory1> ... <theoryN>
  4553   uses <file1> ... <fileM>
  4554   begin
  4555 
  4556 where the 'uses' part is optional.  The previous syntax
  4557 
  4558   theory <name> = <theory1> + ... + <theoryN>:
  4559 
  4560 will disappear in the next release.  Use isatool fixheaders to convert
  4561 existing theory files.  Note that there is no change in ancient
  4562 non-Isar theories now, but these will disappear soon.
  4563 
  4564 * Theory loader: parent theories can now also be referred to via
  4565 relative and absolute paths.
  4566 
  4567 * Command 'find_theorems' searches for a list of criteria instead of a
  4568 list of constants. Known criteria are: intro, elim, dest, name:string,
  4569 simp:term, and any term. Criteria can be preceded by '-' to select
  4570 theorems that do not match. Intro, elim, dest select theorems that
  4571 match the current goal, name:s selects theorems whose fully qualified
  4572 name contain s, and simp:term selects all simplification rules whose
  4573 lhs match term.  Any other term is interpreted as pattern and selects
  4574 all theorems matching the pattern. Available in ProofGeneral under
  4575 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4576 
  4577   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4578 
  4579 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4580 matching the current goal as introduction rule and not having "HOL."
  4581 in their name (i.e. not being defined in theory HOL).
  4582 
  4583 * Command 'thms_containing' has been discontinued in favour of
  4584 'find_theorems'; INCOMPATIBILITY.
  4585 
  4586 * Communication with Proof General is now 8bit clean, which means that
  4587 Unicode text in UTF-8 encoding may be used within theory texts (both
  4588 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4589 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4590 
  4591   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4592   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4593 
  4594 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4595 Classical Reasoner.  Typical big applications run around 2 times
  4596 faster.
  4597 
  4598 
  4599 *** Document preparation ***
  4600 
  4601 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4602 of raw sources.  Only those symbols that do not require additional
  4603 LaTeX packages (depending on comments in isabellesym.sty) are
  4604 displayed properly, everything else is left verbatim.  isatool display
  4605 and isatool print are used as front ends (these are subject to the
  4606 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4607 
  4608 * Command tags control specific markup of certain regions of text,
  4609 notably folding and hiding.  Predefined tags include "theory" (for
  4610 theory begin and end), "proof" for proof commands, and "ML" for
  4611 commands involving ML code; the additional tags "visible" and
  4612 "invisible" are unused by default.  Users may give explicit tag
  4613 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4614 interpretation of tags is determined by the LaTeX job during document
  4615 preparation: see option -V of isatool usedir, or options -n and -t of
  4616 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4617 \isadroptag.
  4618 
  4619 Several document versions may be produced at the same time via isatool
  4620 usedir (the generated index.html will link all of them).  Typical
  4621 specifications include ''-V document=theory,proof,ML'' to present
  4622 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4623 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4624 these parts without any formal replacement text.  The Isabelle site
  4625 default settings produce ''document'' and ''outline'' versions as
  4626 specified above.
  4627 
  4628 * Several new antiquotations:
  4629 
  4630   @{term_type term} prints a term with its type annotated;
  4631 
  4632   @{typeof term} prints the type of a term;
  4633 
  4634   @{const const} is the same as @{term const}, but checks that the
  4635   argument is a known logical constant;
  4636 
  4637   @{term_style style term} and @{thm_style style thm} print a term or
  4638   theorem applying a "style" to it
  4639 
  4640   @{ML text}
  4641 
  4642 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4643 definitions, equations, inequations etc., 'concl' printing only the
  4644 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4645 to print the specified premise.  TermStyle.add_style provides an ML
  4646 interface for introducing further styles.  See also the "LaTeX Sugar"
  4647 document practical applications.  The ML antiquotation prints
  4648 type-checked ML expressions verbatim.
  4649 
  4650 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4651 and 'text' support optional locale specification '(in loc)', which
  4652 specifies the default context for interpreting antiquotations.  For
  4653 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4654 
  4655 * Option 'locale=NAME' of antiquotations specifies an alternative
  4656 context interpreting the subsequent argument.  For example: @{thm
  4657 [locale=lattice] inf_assoc}.
  4658 
  4659 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4660 a proof context.
  4661 
  4662 * Proper output of antiquotations for theory commands involving a
  4663 proof context (such as 'locale' or 'theorem (in loc) ...').
  4664 
  4665 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4666 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4667 
  4668 * isatool usedir: new option -C (default true) controls whether option
  4669 -D should include a copy of the original document directory; -C false
  4670 prevents unwanted effects such as copying of administrative CVS data.
  4671 
  4672 
  4673 *** Pure ***
  4674 
  4675 * Considerably improved version of 'constdefs' command.  Now performs
  4676 automatic type-inference of declared constants; additional support for
  4677 local structure declarations (cf. locales and HOL records), see also
  4678 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4679 sequential dependencies of definitions within a single 'constdefs'
  4680 section; moreover, the declared name needs to be an identifier.  If
  4681 all fails, consider to fall back on 'consts' and 'defs' separately.
  4682 
  4683 * Improved indexed syntax and implicit structures.  First of all,
  4684 indexed syntax provides a notational device for subscripted
  4685 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4686 expressions.  Secondly, in a local context with structure
  4687 declarations, number indexes \<^sub>n or the empty index (default
  4688 number 1) refer to a certain fixed variable implicitly; option
  4689 show_structs controls printing of implicit structures.  Typical
  4690 applications of these concepts involve record types and locales.
  4691 
  4692 * New command 'no_syntax' removes grammar declarations (and
  4693 translations) resulting from the given syntax specification, which is
  4694 interpreted in the same manner as for the 'syntax' command.
  4695 
  4696 * 'Advanced' translation functions (parse_translation etc.) may depend
  4697 on the signature of the theory context being presently used for
  4698 parsing/printing, see also isar-ref manual.
  4699 
  4700 * Improved 'oracle' command provides a type-safe interface to turn an
  4701 ML expression of type theory -> T -> term into a primitive rule of
  4702 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4703 is already included here); see also FOL/ex/IffExample.thy;
  4704 INCOMPATIBILITY.
  4705 
  4706 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4707 before); "cI" is no longer bound, use "c.intro" instead.
  4708 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4709 axclasses vs. locales.
  4710 
  4711 * Improved internal renaming of symbolic identifiers -- attach primes
  4712 instead of base 26 numbers.
  4713 
  4714 * New flag show_question_marks controls printing of leading question
  4715 marks in schematic variable names.
  4716 
  4717 * In schematic variable names, *any* symbol following \<^isub> or
  4718 \<^isup> is now treated as part of the base name.  For example, the
  4719 following works without printing of awkward ".0" indexes:
  4720 
  4721   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4722     by simp
  4723 
  4724 * Inner syntax includes (*(*nested*) comments*).
  4725 
  4726 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4727 annotations as "(00...)".
  4728 
  4729 * Clear separation of logical types and nonterminals, where the latter
  4730 may only occur in 'syntax' specifications or type abbreviations.
  4731 Before that distinction was only partially implemented via type class
  4732 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4733 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4734 exotic syntax specifications may require further adaption
  4735 (e.g. Cube/Cube.thy).
  4736 
  4737 * Removed obsolete type class "logic", use the top sort {} instead.
  4738 Note that non-logical types should be declared as 'nonterminals'
  4739 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4740 specifications.
  4741 
  4742 * Attributes 'induct' and 'cases': type or set names may now be
  4743 locally fixed variables as well.
  4744 
  4745 * Simplifier: can now control the depth to which conditional rewriting
  4746 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4747 Limit.
  4748 
  4749 * Simplifier: simplification procedures may now take the current
  4750 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4751 interface), which is very useful for calling the Simplifier
  4752 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4753 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4754 low-level mk_simproc no longer applies Logic.varify internally, to
  4755 allow for use in a context of fixed variables.
  4756 
  4757 * thin_tac now works even if the assumption being deleted contains !!
  4758 or ==>.  More generally, erule now works even if the major premise of
  4759 the elimination rule contains !! or ==>.
  4760 
  4761 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4762 
  4763 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4764 from Pure, which contains all common declarations already.  Both
  4765 theories are defined via plain Isabelle/Isar .thy files.
  4766 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4767 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4768 use isatool fixcpure to adapt your theory and ML sources.
  4769 
  4770 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4771 selections of theorems in named facts via index ranges.
  4772 
  4773 * 'print_theorems': in theory mode, really print the difference
  4774 wrt. the last state (works for interactive theory development only),
  4775 in proof mode print all local facts (cf. 'print_facts');
  4776 
  4777 * 'hide': option '(open)' hides only base names.
  4778 
  4779 * More efficient treatment of intermediate checkpoints in interactive
  4780 theory development.
  4781 
  4782 * Code generator is now invoked via code_module (incremental code
  4783 generation) and code_library (modular code generation, ML structures
  4784 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4785 must be quoted when used as identifiers.
  4786 
  4787 * New 'value' command for reading, evaluating and printing terms using
  4788 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4789 quoted when used as identifier.
  4790 
  4791 
  4792 *** Locales ***
  4793 
  4794 * New commands for the interpretation of locale expressions in
  4795 theories (1), locales (2) and proof contexts (3).  These generate
  4796 proof obligations from the expression specification.  After the
  4797 obligations have been discharged, theorems of the expression are added
  4798 to the theory, target locale or proof context.  The synopsis of the
  4799 commands is a follows:
  4800 
  4801   (1) interpretation expr inst
  4802   (2) interpretation target < expr
  4803   (3) interpret expr inst
  4804 
  4805 Interpretation in theories and proof contexts require a parameter
  4806 instantiation of terms from the current context.  This is applied to
  4807 specifications and theorems of the interpreted expression.
  4808 Interpretation in locales only permits parameter renaming through the
  4809 locale expression.  Interpretation is smart in that interpretations
  4810 that are active already do not occur in proof obligations, neither are
  4811 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4812 inspect active interpretations of a particular locale.  For details,
  4813 see the Isar Reference manual.  Examples can be found in
  4814 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4815 
  4816 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4817 'interpret' instead.
  4818 
  4819 * New context element 'constrains' for adding type constraints to
  4820 parameters.
  4821 
  4822 * Context expressions: renaming of parameters with syntax
  4823 redeclaration.
  4824 
  4825 * Locale declaration: 'includes' disallowed.
  4826 
  4827 * Proper static binding of attribute syntax -- i.e. types / terms /
  4828 facts mentioned as arguments are always those of the locale definition
  4829 context, independently of the context of later invocations.  Moreover,
  4830 locale operations (renaming and type / term instantiation) are applied
  4831 to attribute arguments as expected.
  4832 
  4833 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4834 actual attributes; rare situations may require Attrib.attribute to
  4835 embed those attributes into Attrib.src that lack concrete syntax.
  4836 Attribute implementations need to cooperate properly with the static
  4837 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4838 Attrib.XXX_thm etc. already do the right thing without further
  4839 intervention.  Only unusual applications -- such as "where" or "of"
  4840 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4841 on the context and the facts involved -- may have to assign parsed
  4842 values to argument tokens explicitly.
  4843 
  4844 * Changed parameter management in theorem generation for long goal
  4845 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4846 theorem statement in rare situations.
  4847 
  4848 * Locale inspection command 'print_locale' omits notes elements.  Use
  4849 'print_locale!' to have them included in the output.
  4850 
  4851 
  4852 *** Provers ***
  4853 
  4854 * Provers/hypsubst.ML: improved version of the subst method, for
  4855 single-step rewriting: it now works in bound variable contexts. New is
  4856 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4857 rewrite a different subterm than the original subst method, which is
  4858 still available as 'simplesubst'.
  4859 
  4860 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4861 and quasi orders.
  4862 
  4863 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4864 reflexive-transitive closure of relations.
  4865 
  4866 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4867 limit (previously hard-coded with a value of 20) user-definable.
  4868 
  4869 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4870 is peformed already.  Object-logics merely need to finish their
  4871 initial simpset configuration as before.  INCOMPATIBILITY.
  4872 
  4873 
  4874 *** HOL ***
  4875 
  4876 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4877 
  4878   syntax (epsilon)
  4879     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4880 
  4881 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4882 and x-symbol; use option '-m epsilon' to get it actually printed.
  4883 Moreover, the mathematically important symbolic identifier \<epsilon>
  4884 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4885 
  4886 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  4887 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  4888 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  4889 support corresponding Isar calculations.
  4890 
  4891 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  4892 instead of ":".
  4893 
  4894 * theory SetInterval: changed the syntax for open intervals:
  4895 
  4896   Old       New
  4897   {..n(}    {..<n}
  4898   {)n..}    {n<..}
  4899   {m..n(}   {m..<n}
  4900   {)m..n}   {m<..n}
  4901   {)m..n(}  {m<..<n}
  4902 
  4903 The old syntax is still supported but will disappear in the next
  4904 release.  For conversion use the following Emacs search and replace
  4905 patterns (these are not perfect but work quite well):
  4906 
  4907   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  4908   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  4909 
  4910 * Theory Commutative_Ring (in Library): method comm_ring for proving
  4911 equalities in commutative rings; method 'algebra' provides a generic
  4912 interface.
  4913 
  4914 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  4915 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  4916 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  4917 be a tuple pattern.
  4918 
  4919 Some new syntax forms are available:
  4920 
  4921   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  4922   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  4923   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  4924   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  4925 
  4926 The latter form "\<Sum>x < k. e" used to be based on a separate
  4927 function "Summation", which has been discontinued.
  4928 
  4929 * theory Finite_Set: in structured induction proofs, the insert case
  4930 is now 'case (insert x F)' instead of the old counterintuitive 'case
  4931 (insert F x)'.
  4932 
  4933 * The 'refute' command has been extended to support a much larger
  4934 fragment of HOL, including axiomatic type classes, constdefs and
  4935 typedefs, inductive datatypes and recursion.
  4936 
  4937 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  4938 Requires zChaff with proof generation to be installed.  See
  4939 HOL/ex/SAT_Examples.thy for examples.
  4940 
  4941 * Datatype induction via method 'induct' now preserves the name of the
  4942 induction variable. For example, when proving P(xs::'a list) by
  4943 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  4944 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  4945 in unstructured proof scripts.
  4946 
  4947 * Reworked implementation of records.  Improved scalability for
  4948 records with many fields, avoiding performance problems for type
  4949 inference. Records are no longer composed of nested field types, but
  4950 of nested extension types. Therefore the record type only grows linear
  4951 in the number of extensions and not in the number of fields.  The
  4952 top-level (users) view on records is preserved.  Potential
  4953 INCOMPATIBILITY only in strange cases, where the theory depends on the
  4954 old record representation. The type generated for a record is called
  4955 <record_name>_ext_type.
  4956 
  4957 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  4958 proofs triggered by a record definition or a simproc (if
  4959 quick_and_dirty is enabled).  Definitions of large records can take
  4960 quite long.
  4961 
  4962 New simproc record_upd_simproc for simplification of multiple record
  4963 updates enabled by default.  Moreover, trivial updates are also
  4964 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  4965 occasionally, since simplification is more powerful by default.
  4966 
  4967 * typedef: proper support for polymorphic sets, which contain extra
  4968 type-variables in the term.
  4969 
  4970 * Simplifier: automatically reasons about transitivity chains
  4971 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  4972 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  4973 old proofs break occasionally as simplification may now solve more
  4974 goals than previously.
  4975 
  4976 * Simplifier: converts x <= y into x = y if assumption y <= x is
  4977 present.  Works for all partial orders (class "order"), in particular
  4978 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  4979 just like y <= x.
  4980 
  4981 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  4982 bound variable or a constant then the let is unfolded.  Otherwise
  4983 first a is simplified to b, and then f b is simplified to g. If
  4984 possible we abstract b from g arriving at "let x = b in h x",
  4985 otherwise we unfold the let and arrive at g.  The simproc can be
  4986 enabled/disabled by the reference use_let_simproc.  Potential
  4987 INCOMPATIBILITY since simplification is more powerful by default.
  4988 
  4989 * Classical reasoning: the meson method now accepts theorems as arguments.
  4990 
  4991 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  4992 jobs to provide advice on the provability of subgoals.
  4993 
  4994 * Theory OrderedGroup and Ring_and_Field: various additions and
  4995 improvements to faciliate calculations involving equalities and
  4996 inequalities.
  4997 
  4998 The following theorems have been eliminated or modified
  4999 (INCOMPATIBILITY):
  5000 
  5001   abs_eq             now named abs_of_nonneg
  5002   abs_of_ge_0        now named abs_of_nonneg
  5003   abs_minus_eq       now named abs_of_nonpos
  5004   imp_abs_id         now named abs_of_nonneg
  5005   imp_abs_neg_id     now named abs_of_nonpos
  5006   mult_pos           now named mult_pos_pos
  5007   mult_pos_le        now named mult_nonneg_nonneg
  5008   mult_pos_neg_le    now named mult_nonneg_nonpos
  5009   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5010   mult_neg           now named mult_neg_neg
  5011   mult_neg_le        now named mult_nonpos_nonpos
  5012 
  5013 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5014      
  5015      zero_le_square
  5016      not_square_less_zero 
  5017 
  5018   The following lemmas have been deleted from Real/RealPow:
  5019   
  5020      realpow_zero_zero
  5021      realpow_two
  5022      realpow_less
  5023      zero_le_power
  5024      realpow_two_le
  5025      abs_realpow_two
  5026      realpow_two_abs     
  5027 
  5028 * Theory Parity: added rules for simplifying exponents.
  5029 
  5030 * Theory List:
  5031 
  5032 The following theorems have been eliminated or modified
  5033 (INCOMPATIBILITY):
  5034 
  5035   list_all_Nil       now named list_all.simps(1)
  5036   list_all_Cons      now named list_all.simps(2)
  5037   list_all_conv      now named list_all_iff
  5038   set_mem_eq         now named mem_iff
  5039 
  5040 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5041 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5042 
  5043 
  5044 *** HOL-Complex ***
  5045 
  5046 * Theory RealDef: better support for embedding natural numbers and
  5047 integers in the reals.
  5048 
  5049 The following theorems have been eliminated or modified
  5050 (INCOMPATIBILITY):
  5051 
  5052   exp_ge_add_one_self  now requires no hypotheses
  5053   real_of_int_add      reversed direction of equality (use [symmetric])
  5054   real_of_int_minus    reversed direction of equality (use [symmetric])
  5055   real_of_int_diff     reversed direction of equality (use [symmetric])
  5056   real_of_int_mult     reversed direction of equality (use [symmetric])
  5057 
  5058 * Theory RComplete: expanded support for floor and ceiling functions.
  5059 
  5060 * Theory Ln is new, with properties of the natural logarithm
  5061 
  5062 * Hyperreal: There is a new type constructor "star" for making
  5063 nonstandard types.  The old type names are now type synonyms:
  5064 
  5065   hypreal = real star
  5066   hypnat = nat star
  5067   hcomplex = complex star
  5068 
  5069 * Hyperreal: Many groups of similarly-defined constants have been
  5070 replaced by polymorphic versions (INCOMPATIBILITY):
  5071 
  5072   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5073 
  5074   starset      <-- starsetNat, starsetC
  5075   *s*          <-- *sNat*, *sc*
  5076   starset_n    <-- starsetNat_n, starsetC_n
  5077   *sn*         <-- *sNatn*, *scn*
  5078   InternalSets <-- InternalNatSets, InternalCSets
  5079 
  5080   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5081   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5082   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5083   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5084   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5085 
  5086 * Hyperreal: Many type-specific theorems have been removed in favor of
  5087 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5088 
  5089   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5090   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5091   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5092   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5093   right_minus <-- hypreal_add_minus
  5094   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5095   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5096   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5097   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5098   mult_1_right <-- hcomplex_mult_one_right
  5099   mult_zero_left <-- hcomplex_mult_zero_left
  5100   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5101   right_distrib <-- hypnat_add_mult_distrib2
  5102   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5103   right_inverse <-- hypreal_mult_inverse
  5104   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5105   order_refl <-- {hypreal,hypnat}_le_refl
  5106   order_trans <-- {hypreal,hypnat}_le_trans
  5107   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5108   order_less_le <-- {hypreal,hypnat}_less_le
  5109   linorder_linear <-- {hypreal,hypnat}_le_linear
  5110   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5111   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5112   add_nonneg_nonneg <-- hypreal_le_add_order
  5113 
  5114 * Hyperreal: Separate theorems having to do with type-specific
  5115 versions of constants have been merged into theorems that apply to the
  5116 new polymorphic constants (INCOMPATIBILITY):
  5117 
  5118   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5119   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5120   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5121   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5122   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5123   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5124   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5125   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5126   STAR_diff <-- {STAR,STARC}_diff
  5127   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5128     STARC_hcomplex_of_complex}_image_subset
  5129   starset_n_Un <-- starset{Nat,C}_n_Un
  5130   starset_n_Int <-- starset{Nat,C}_n_Int
  5131   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5132   starset_n_diff <-- starset{Nat,C}_n_diff
  5133   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5134   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5135   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5136   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5137   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5138   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5139   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5140   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5141   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5142   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5143   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5144   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5145   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5146   starfun_diff <-- starfun{C,RC,CR}_diff
  5147   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5148   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5149   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5150   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5151   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5152   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5153   starfun_Id <-- starfunC_Id
  5154   starfun_approx <-- starfun{Nat,CR}_approx
  5155   starfun_capprox <-- starfun{C,RC}_capprox
  5156   starfun_abs <-- starfunNat_rabs
  5157   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5158   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5159   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5160   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5161   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5162   starfun_add_approx <-- starfunCR_add_approx
  5163   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5164   starfun_divide <-- starfun{C,CR,RC}_divide
  5165   starfun_n <-- starfun{Nat,C}_n
  5166   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5167   starfun_n_add <-- starfun{Nat,C}_n_add
  5168   starfun_n_add_minus <-- starfunNat_n_add_minus
  5169   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5170   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5171   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5172 
  5173   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5174   star_n_minus <-- {hypreal,hcomplex}_minus
  5175   star_n_diff <-- {hypreal,hcomplex}_diff
  5176   star_n_mult <-- {hypreal,hcomplex}_mult
  5177   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5178   star_n_le <-- {hypreal,hypnat}_le
  5179   star_n_less <-- {hypreal,hypnat}_less
  5180   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5181   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5182   star_n_abs <-- hypreal_hrabs
  5183   star_n_divide <-- hcomplex_divide
  5184 
  5185   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5186   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5187   star_of_diff <-- hypreal_of_real_diff
  5188   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5189   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5190   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5191   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5192   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5193   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5194   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5195   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5196   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5197   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5198   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5199   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5200   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5201   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5202   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5203   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5204   star_of_power <-- hypreal_of_real_power
  5205   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5206 
  5207 * Hyperreal: new method "transfer" that implements the transfer
  5208 principle of nonstandard analysis. With a subgoal that mentions
  5209 nonstandard types like "'a star", the command "apply transfer"
  5210 replaces it with an equivalent one that mentions only standard types.
  5211 To be successful, all free variables must have standard types; non-
  5212 standard variables must have explicit universal quantifiers.
  5213 
  5214 * Hyperreal: A theory of Taylor series.
  5215 
  5216 
  5217 *** HOLCF ***
  5218 
  5219 * Discontinued special version of 'constdefs' (which used to support
  5220 continuous functions) in favor of the general Pure one with full
  5221 type-inference.
  5222 
  5223 * New simplification procedure for solving continuity conditions; it
  5224 is much faster on terms with many nested lambda abstractions (cubic
  5225 instead of exponential time).
  5226 
  5227 * New syntax for domain package: selector names are now optional.
  5228 Parentheses should be omitted unless argument is lazy, for example:
  5229 
  5230   domain 'a stream = cons "'a" (lazy "'a stream")
  5231 
  5232 * New command 'fixrec' for defining recursive functions with pattern
  5233 matching; defining multiple functions with mutual recursion is also
  5234 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5235 sinr, or any data constructor defined by the domain package. The given
  5236 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5237 syntax and examples.
  5238 
  5239 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5240 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5241 but the proof obligation additionally includes an admissibility
  5242 requirement. The packages generate instances of class cpo or pcpo,
  5243 with continuity and strictness theorems for Rep and Abs.
  5244 
  5245 * HOLCF: Many theorems have been renamed according to a more standard naming
  5246 scheme (INCOMPATIBILITY):
  5247 
  5248   foo_inject:  "foo$x = foo$y ==> x = y"
  5249   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5250   foo_less:    "(foo$x << foo$y) = (x << y)"
  5251   foo_strict:  "foo$UU = UU"
  5252   foo_defined: "... ==> foo$x ~= UU"
  5253   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5254 
  5255 
  5256 *** ZF ***
  5257 
  5258 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5259 including the First Isomorphism Theorem (on quotienting by the kernel
  5260 of a homomorphism).
  5261 
  5262 * ZF/Simplifier: install second copy of type solver that actually
  5263 makes use of TC rules declared to Isar proof contexts (or locales);
  5264 the old version is still required for ML proof scripts.
  5265 
  5266 
  5267 *** Cube ***
  5268 
  5269 * Converted to Isar theory format; use locales instead of axiomatic
  5270 theories.
  5271 
  5272 
  5273 *** ML ***
  5274 
  5275 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5276 for ||>, ||>>, |>>,
  5277 
  5278 * Pure/library.ML no longer defines its own option datatype, but uses
  5279 that of the SML basis, which has constructors NONE and SOME instead of
  5280 None and Some, as well as exception Option.Option instead of OPTION.
  5281 The functions the, if_none, is_some, is_none have been adapted
  5282 accordingly, while Option.map replaces apsome.
  5283 
  5284 * Pure/library.ML: the exception LIST has been given up in favour of
  5285 the standard exceptions Empty and Subscript, as well as
  5286 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5287 superceded by the standard hd and tl functions etc.
  5288 
  5289 A number of basic list functions are no longer exported to the ML
  5290 toplevel, as they are variants of predefined functions.  The following
  5291 suggests how one can translate existing code:
  5292 
  5293     rev_append xs ys = List.revAppend (xs, ys)
  5294     nth_elem (i, xs) = List.nth (xs, i)
  5295     last_elem xs = List.last xs
  5296     flat xss = List.concat xss
  5297     seq fs = List.app fs
  5298     partition P xs = List.partition P xs
  5299     mapfilter f xs = List.mapPartial f xs
  5300 
  5301 * Pure/library.ML: several combinators for linear functional
  5302 transformations, notably reverse application and composition:
  5303 
  5304   x |> f                f #> g
  5305   (x, y) |-> f          f #-> g
  5306 
  5307 * Pure/library.ML: introduced/changed precedence of infix operators:
  5308 
  5309   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5310   infix 2 ?;
  5311   infix 3 o oo ooo oooo;
  5312   infix 4 ~~ upto downto;
  5313 
  5314 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5315 infix operators.
  5316 
  5317 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5318 fold_map support linear functional transformations and nesting.  For
  5319 example:
  5320 
  5321   fold f [x1, ..., xN] y =
  5322     y |> f x1 |> ... |> f xN
  5323 
  5324   (fold o fold) f [xs1, ..., xsN] y =
  5325     y |> fold f xs1 |> ... |> fold f xsN
  5326 
  5327   fold f [x1, ..., xN] =
  5328     f x1 #> ... #> f xN
  5329 
  5330   (fold o fold) f [xs1, ..., xsN] =
  5331     fold f xs1 #> ... #> fold f xsN
  5332 
  5333 * Pure/library.ML: the following selectors on type 'a option are
  5334 available:
  5335 
  5336   the:               'a option -> 'a  (*partial*)
  5337   these:             'a option -> 'a  where 'a = 'b list
  5338   the_default: 'a -> 'a option -> 'a
  5339   the_list:          'a option -> 'a list
  5340 
  5341 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5342 basic operations for association lists, following natural argument
  5343 order; moreover the explicit equality predicate passed here avoids
  5344 potentially expensive polymorphic runtime equality checks.
  5345 The old functions may be expressed as follows:
  5346 
  5347   assoc = uncurry (AList.lookup (op =))
  5348   assocs = these oo AList.lookup (op =)
  5349   overwrite = uncurry (AList.update (op =)) o swap
  5350 
  5351 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5352 
  5353   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5354   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5355 
  5356 replacing make_keylist and keyfilter (occassionally used)
  5357 Naive rewrites:
  5358 
  5359   make_keylist = AList.make
  5360   keyfilter = AList.find (op =)
  5361 
  5362 * eq_fst and eq_snd now take explicit equality parameter, thus
  5363   avoiding eqtypes. Naive rewrites:
  5364 
  5365     eq_fst = eq_fst (op =)
  5366     eq_snd = eq_snd (op =)
  5367 
  5368 * Removed deprecated apl and apr (rarely used).
  5369   Naive rewrites:
  5370 
  5371     apl (n, op) =>>= curry op n
  5372     apr (op, m) =>>= fn n => op (n, m)
  5373 
  5374 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5375 provides a reasonably efficient light-weight implementation of sets as
  5376 lists.
  5377 
  5378 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5379 few new operations; existing lookup and update are now curried to
  5380 follow natural argument order (for use with fold etc.);
  5381 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5382 
  5383 * Pure/General: output via the Isabelle channels of
  5384 writeln/warning/error etc. is now passed through Output.output, with a
  5385 hook for arbitrary transformations depending on the print_mode
  5386 (cf. Output.add_mode -- the first active mode that provides a output
  5387 function wins).  Already formatted output may be embedded into further
  5388 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5389 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5390 accommodate easy composition of diagnostic messages etc.  Programmers
  5391 rarely need to care about Output.output or Output.raw at all, with
  5392 some notable exceptions: Output.output is required when bypassing the
  5393 standard channels (writeln etc.), or in token translations to produce
  5394 properly formatted results; Output.raw is required when capturing
  5395 already output material that will eventually be presented to the user
  5396 a second time.  For the default print mode, both Output.output and
  5397 Output.raw have no effect.
  5398 
  5399 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5400 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5401 cumulative results are displayed at the end of a batch session.
  5402 
  5403 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5404 replaced by File.platform_path and File.shell_path (with appropriate
  5405 hooks).  This provides a clean interface for unusual systems where the
  5406 internal and external process view of file names are different.
  5407 
  5408 * Pure: more efficient orders for basic syntactic entities: added
  5409 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5410 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5411 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5412 orders now -- potential INCOMPATIBILITY for code that depends on a
  5413 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5414 Library.sort_strings on result).
  5415 
  5416 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5417 fold_types traverse types/terms from left to right, observing natural
  5418 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5419 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5420 
  5421 * Pure: name spaces have been refined, with significant changes of the
  5422 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5423 to extern(_table).  The plain name entry path is superceded by a
  5424 general 'naming' context, which also includes the 'policy' to produce
  5425 a fully qualified name and external accesses of a fully qualified
  5426 name; NameSpace.extend is superceded by context dependent
  5427 Sign.declare_name.  Several theory and proof context operations modify
  5428 the naming context.  Especially note Theory.restore_naming and
  5429 ProofContext.restore_naming to get back to a sane state; note that
  5430 Theory.add_path is no longer sufficient to recover from
  5431 Theory.absolute_path in particular.
  5432 
  5433 * Pure: new flags short_names (default false) and unique_names
  5434 (default true) for controlling output of qualified names.  If
  5435 short_names is set, names are printed unqualified.  If unique_names is
  5436 reset, the name prefix is reduced to the minimum required to achieve
  5437 the original result when interning again, even if there is an overlap
  5438 with earlier declarations.
  5439 
  5440 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5441 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5442 (useful for printing error messages).  INCOMPATIBILITY.
  5443 
  5444 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5445 Theory.theory are now identified, referring to the universal
  5446 Context.theory (see Pure/context.ML).  Actual signature and theory
  5447 content is managed as theory data.  The old code and interfaces were
  5448 spread over many files and structures; the new arrangement introduces
  5449 considerable INCOMPATIBILITY to gain more clarity:
  5450 
  5451   Context -- theory management operations (name, identity, inclusion,
  5452     parents, ancestors, merge, etc.), plus generic theory data;
  5453 
  5454   Sign -- logical signature and syntax operations (declaring consts,
  5455     types, etc.), plus certify/read for common entities;
  5456 
  5457   Theory -- logical theory operations (stating axioms, definitions,
  5458     oracles), plus a copy of logical signature operations (consts,
  5459     types, etc.); also a few basic management operations (Theory.copy,
  5460     Theory.merge, etc.)
  5461 
  5462 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5463 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5464 for convenience -- they merely return the theory.
  5465 
  5466 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5467 
  5468 * Pure: the Isar proof context type is already defined early in Pure
  5469 as Context.proof (note that ProofContext.context and Proof.context are
  5470 aliases, where the latter is the preferred name).  This enables other
  5471 Isabelle components to refer to that type even before Isar is present.
  5472 
  5473 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5474 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5475 any of these kinds.  For example, Sign.intern typeK is now
  5476 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5477 Theory.hide_types.  Also note that former
  5478 Theory.hide_classes/types/consts are now
  5479 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5480 internalize their arguments!  INCOMPATIBILITY.
  5481 
  5482 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5483 datatype thmref (with constructors Name and NameSelection) instead of
  5484 plain string -- INCOMPATIBILITY;
  5485 
  5486 * Pure: cases produced by proof methods specify options, where NONE
  5487 means to remove case bindings -- INCOMPATIBILITY in
  5488 (RAW_)METHOD_CASES.
  5489 
  5490 * Pure: the following operations retrieve axioms or theorems from a
  5491 theory node or theory hierarchy, respectively:
  5492 
  5493   Theory.axioms_of: theory -> (string * term) list
  5494   Theory.all_axioms_of: theory -> (string * term) list
  5495   PureThy.thms_of: theory -> (string * thm) list
  5496   PureThy.all_thms_of: theory -> (string * thm) list
  5497 
  5498 * Pure: print_tac now outputs the goal through the trace channel.
  5499 
  5500 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5501 Reference Toplevel.debug (default false) controls detailed printing
  5502 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5503 controls execution profiling -- set to 1 for time and 2 for space
  5504 (both increase the runtime).
  5505 
  5506 * Isar session: The initial use of ROOT.ML is now always timed,
  5507 i.e. the log will show the actual process times, in contrast to the
  5508 elapsed wall-clock time that the outer shell wrapper produces.
  5509 
  5510 * Simplifier: improved handling of bound variables (nameless
  5511 representation, avoid allocating new strings).  Simprocs that invoke
  5512 the Simplifier recursively should use Simplifier.inherit_bounds to
  5513 avoid local name clashes.  Failure to do so produces warnings
  5514 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5515 for further details.
  5516 
  5517 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5518 bindings for all theorems stored within a given theory; this may help
  5519 in porting non-Isar theories to Isar ones, while keeping ML proof
  5520 scripts for the time being.
  5521 
  5522 * ML operator HTML.with_charset specifies the charset begin used for
  5523 generated HTML files.  For example:
  5524 
  5525   HTML.with_charset "utf-8" use_thy "Hebrew";
  5526   HTML.with_charset "utf-8" use_thy "Chinese";
  5527 
  5528 
  5529 *** System ***
  5530 
  5531 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5532 isabelle, isatool etc.).
  5533 
  5534 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5535 isatool doc, isatool mkdir, display_drafts etc.).
  5536 
  5537 * isatool usedir: option -f allows specification of the ML file to be
  5538 used by Isabelle; default is ROOT.ML.
  5539 
  5540 * New isatool version outputs the version identifier of the Isabelle
  5541 distribution being used.
  5542 
  5543 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5544 (containing Boolean satisfiability problems) into Isabelle/HOL
  5545 theories.
  5546 
  5547 
  5548 
  5549 New in Isabelle2004 (April 2004)
  5550 --------------------------------
  5551 
  5552 *** General ***
  5553 
  5554 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5555   Replaces linorder.ML.
  5556 
  5557 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5558   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5559   (\<a>...\<z>), are now considered normal letters, and can therefore
  5560   be used anywhere where an ASCII letter (a...zA...Z) has until
  5561   now. COMPATIBILITY: This obviously changes the parsing of some
  5562   terms, especially where a symbol has been used as a binder, say
  5563   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5564   as an identifier.  Fix it by inserting a space around former
  5565   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5566   existing theory and ML files.
  5567 
  5568 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5569 
  5570 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5571   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5572   a normal (but invisible) letter. For multiple letter subscripts repeat
  5573   \<^isub> like this: x\<^isub>1\<^isub>2.
  5574 
  5575 * Pure: There are now sub-/superscripts that can span more than one
  5576   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5577   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5578   superscript. The new control characters are not identifier parts.
  5579 
  5580 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5581   content of "..." to the latex file instead of \isacntrl... . The "..."
  5582   may consist of any printable characters excluding the end bracket >.
  5583 
  5584 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5585   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5586   declare constants "final", which prevents their being given a definition
  5587   later.  It is useful for constants whose behaviour is fixed axiomatically
  5588   rather than definitionally, such as the meta-logic connectives.
  5589 
  5590 * Pure: 'instance' now handles general arities with general sorts
  5591   (i.e. intersections of classes),
  5592 
  5593 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5594   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5595   It can be changed to alter the colors/layout of generated pages.
  5596 
  5597 
  5598 *** Isar ***
  5599 
  5600 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5601   cut_tac, subgoal_tac and thin_tac:
  5602   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5603     locales are no longer forced to write Isar proof scripts.
  5604     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5605     emulations.
  5606   - INCOMPATIBILITY: names of variables to be instantiated may no
  5607     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5608     This is consistent with the instantiation attribute "where".
  5609 
  5610 * Attributes "where" and "of":
  5611   - Now take type variables of instantiated theorem into account when reading
  5612     the instantiation string.  This fixes a bug that caused instantiated
  5613     theorems to have too special types in some circumstances.
  5614   - "where" permits explicit instantiations of type variables.
  5615 
  5616 * Calculation commands "moreover" and "also" no longer interfere with
  5617   current facts ("this"), admitting arbitrary combinations with "then"
  5618   and derived forms.
  5619 
  5620 * Locales:
  5621   - Goal statements involving the context element "includes" no longer
  5622     generate theorems with internal delta predicates (those ending on
  5623     "_axioms") in the premise.
  5624     Resolve particular premise with <locale>.intro to obtain old form.
  5625   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5626     specification and "includes" elements in goal statement.
  5627   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5628     [intro?] and [elim?] (respectively) by default.
  5629   - Experimental command for instantiation of locales in proof contexts:
  5630         instantiate <label>[<attrs>]: <loc>
  5631     Instantiates locale <loc> and adds all its theorems to the current context
  5632     taking into account their attributes.  Label and attrs are optional
  5633     modifiers, like in theorem declarations.  If present, names of
  5634     instantiated theorems are qualified with <label>, and the attributes
  5635     <attrs> are applied after any attributes these theorems might have already.
  5636       If the locale has assumptions, a chained fact of the form
  5637     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5638     are derived.  The command does not support old-style locales declared
  5639     with "locale (open)".
  5640       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5641 
  5642 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5643   (Isar) contexts.
  5644 
  5645 
  5646 *** HOL ***
  5647 
  5648 * Proof import: new image HOL4 contains the imported library from
  5649   the HOL4 system with about 2500 theorems. It is imported by
  5650   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5651   can be used like any other Isabelle image.  See
  5652   HOL/Import/HOL/README for more information.
  5653 
  5654 * Simplifier:
  5655   - Much improved handling of linear and partial orders.
  5656     Reasoners for linear and partial orders are set up for type classes
  5657     "linorder" and "order" respectively, and are added to the default simpset
  5658     as solvers.  This means that the simplifier can build transitivity chains
  5659     to solve goals from the assumptions.
  5660   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5661     of blast or auto after simplification become unnecessary because the goal
  5662     is solved by simplification already.
  5663 
  5664 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5665     all proved in axiomatic type classes for semirings, rings and fields.
  5666 
  5667 * Numerics:
  5668   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5669     now formalized using the Ring_and_Field theory mentioned above.
  5670   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5671     than before, because now they are set up once in a generic manner.
  5672   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5673     Look for the general versions in Ring_and_Field (and Power if they concern
  5674     exponentiation).
  5675 
  5676 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5677 
  5678 * Records:
  5679   - Record types are now by default printed with their type abbreviation
  5680     instead of the list of all field types. This can be configured via
  5681     the reference "print_record_type_abbr".
  5682   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5683     (not enabled by default).
  5684   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5685     EX x. x = sel r to True (not enabled by default).
  5686   - Tactic "record_split_simp_tac" to split and simplify records added.
  5687 
  5688 * 'specification' command added, allowing for definition by
  5689   specification.  There is also an 'ax_specification' command that
  5690   introduces the new constants axiomatically.
  5691 
  5692 * arith(_tac) is now able to generate counterexamples for reals as well.
  5693 
  5694 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5695 
  5696 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5697   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5698 
  5699 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5700   matrix theory to linear programming.
  5701 
  5702 * Unions and Intersections:
  5703   The latex output syntax of UN and INT has been changed
  5704   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5705   i.e. the index formulae has become a subscript.
  5706   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5707 
  5708 * Unions and Intersections over Intervals:
  5709   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5710   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5711   like in normal math, and corresponding versions for < and for intersection.
  5712 
  5713 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5714   lexicographic dictonary ordering has been added as "lexord".
  5715 
  5716 * ML: the legacy theory structures Int and List have been removed. They had
  5717   conflicted with ML Basis Library structures having the same names.
  5718 
  5719 * 'refute' command added to search for (finite) countermodels.  Only works
  5720   for a fragment of HOL.  The installation of an external SAT solver is
  5721   highly recommended.  See "HOL/Refute.thy" for details.
  5722 
  5723 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5724   formulae under an assignment of free variables to random values.
  5725   In contrast to 'refute', it can deal with inductive datatypes,
  5726   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5727   for examples.
  5728 
  5729 
  5730 *** HOLCF ***
  5731 
  5732 * Streams now come with concatenation and are part of the HOLCF image
  5733 
  5734 
  5735 
  5736 New in Isabelle2003 (May 2003)
  5737 ------------------------------
  5738 
  5739 *** General ***
  5740 
  5741 * Provers/simplifier:
  5742 
  5743   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5744     Assumptions are now subject to complete mutual simplification,
  5745     not just from left to right. The simplifier now preserves
  5746     the order of assumptions.
  5747 
  5748     Potential INCOMPATIBILITY:
  5749 
  5750     -- simp sometimes diverges where the old version did
  5751        not, e.g. invoking simp on the goal
  5752 
  5753         [| P (f x); y = x; f x = f y |] ==> Q
  5754 
  5755        now gives rise to the infinite reduction sequence
  5756 
  5757         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5758 
  5759        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5760        kind of problem.
  5761 
  5762     -- Tactics combining classical reasoner and simplification (such as auto)
  5763        are also affected by this change, because many of them rely on
  5764        simp. They may sometimes diverge as well or yield a different numbers
  5765        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5766        in case of problems. Sometimes subsequent calls to the classical
  5767        reasoner will fail because a preceeding call to the simplifier too
  5768        eagerly simplified the goal, e.g. deleted redundant premises.
  5769 
  5770   - The simplifier trace now shows the names of the applied rewrite rules
  5771 
  5772   - You can limit the number of recursive invocations of the simplifier
  5773     during conditional rewriting (where the simplifie tries to solve the
  5774     conditions before applying the rewrite rule):
  5775     ML "simp_depth_limit := n"
  5776     where n is an integer. Thus you can force termination where previously
  5777     the simplifier would diverge.
  5778 
  5779   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5780 
  5781   - No longer aborts on failed congruence proof.  Instead, the
  5782     congruence is ignored.
  5783 
  5784 * Pure: New generic framework for extracting programs from constructive
  5785   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5786   as HOL/Extraction for some case studies.
  5787 
  5788 * Pure: The main goal of the proof state is no longer shown by default, only
  5789 the subgoals. This behaviour is controlled by a new flag.
  5790    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5791 (ML: Proof.show_main_goal).
  5792 
  5793 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5794 rules whose conclusion matches subgoal 1:
  5795       PG menu: Isabelle/Isar -> Show me -> matching rules
  5796 The rules are ordered by how closely they match the subgoal.
  5797 In particular, rules that solve a subgoal outright are displayed first
  5798 (or rather last, the way they are printed).
  5799 (ML: ProofGeneral.print_intros())
  5800 
  5801 * Pure: New flag trace_unify_fail causes unification to print
  5802 diagnostic information (PG: in trace buffer) when it fails. This is
  5803 useful for figuring out why single step proofs like rule, erule or
  5804 assumption failed.
  5805 
  5806 * Pure: Locale specifications now produce predicate definitions
  5807 according to the body of text (covering assumptions modulo local
  5808 definitions); predicate "loc_axioms" covers newly introduced text,
  5809 while "loc" is cumulative wrt. all included locale expressions; the
  5810 latter view is presented only on export into the global theory
  5811 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5812 on the old view without predicates;
  5813 
  5814 * Pure: predefined locales "var" and "struct" are useful for sharing
  5815 parameters (as in CASL, for example); just specify something like
  5816 ``var x + var y + struct M'' as import;
  5817 
  5818 * Pure: improved thms_containing: proper indexing of facts instead of
  5819 raw theorems; check validity of results wrt. current name space;
  5820 include local facts of proof configuration (also covers active
  5821 locales), cover fixed variables in index; may use "_" in term
  5822 specification; an optional limit for the number of printed facts may
  5823 be given (the default is 40);
  5824 
  5825 * Pure: disallow duplicate fact bindings within new-style theory files
  5826 (batch-mode only);
  5827 
  5828 * Provers: improved induct method: assumptions introduced by case
  5829 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5830 the goal statement); "foo" still refers to all facts collectively;
  5831 
  5832 * Provers: the function blast.overloaded has been removed: all constants
  5833 are regarded as potentially overloaded, which improves robustness in exchange
  5834 for slight decrease in efficiency;
  5835 
  5836 * Provers/linorder: New generic prover for transitivity reasoning over
  5837 linear orders.  Note: this prover is not efficient!
  5838 
  5839 * Isar: preview of problems to finish 'show' now produce an error
  5840 rather than just a warning (in interactive mode);
  5841 
  5842 
  5843 *** HOL ***
  5844 
  5845 * arith(_tac)
  5846 
  5847  - Produces a counter example if it cannot prove a goal.
  5848    Note that the counter example may be spurious if the goal is not a formula
  5849    of quantifier-free linear arithmetic.
  5850    In ProofGeneral the counter example appears in the trace buffer.
  5851 
  5852  - Knows about div k and mod k where k is a numeral of type nat or int.
  5853 
  5854  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5855    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5856    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5857 
  5858 * simp's arithmetic capabilities have been enhanced a bit: it now
  5859 takes ~= in premises into account (by performing a case split);
  5860 
  5861 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5862 are distributed over a sum of terms;
  5863 
  5864 * New tactic "trans_tac" and method "trans" instantiate
  5865 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5866 "<=", "<" and "=").
  5867 
  5868 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5869 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5870 
  5871 * 'typedef' command has new option "open" to suppress the set
  5872 definition;
  5873 
  5874 * functions Min and Max on finite sets have been introduced (theory
  5875 Finite_Set);
  5876 
  5877 * attribute [symmetric] now works for relations as well; it turns
  5878 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5879 
  5880 * induct over a !!-quantified statement (say !!x1..xn):
  5881   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5882 
  5883 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5884 %x. None. Warning: empty_def now refers to the previously hidden definition
  5885 of the empty set.
  5886 
  5887 * Algebra: formalization of classical algebra.  Intended as base for
  5888 any algebraic development in Isabelle.  Currently covers group theory
  5889 (up to Sylow's theorem) and ring theory (Universal Property of
  5890 Univariate Polynomials).  Contributions welcome;
  5891 
  5892 * GroupTheory: deleted, since its material has been moved to Algebra;
  5893 
  5894 * Complex: new directory of the complex numbers with numeric constants,
  5895 nonstandard complex numbers, and some complex analysis, standard and
  5896 nonstandard (Jacques Fleuriot);
  5897 
  5898 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  5899 
  5900 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  5901 Fleuriot);
  5902 
  5903 * Real/HahnBanach: updated and adapted to locales;
  5904 
  5905 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  5906 Gray and Kramer);
  5907 
  5908 * UNITY: added the Meier-Sanders theory of progress sets;
  5909 
  5910 * MicroJava: bytecode verifier and lightweight bytecode verifier
  5911 as abstract algorithms, instantiated to the JVM;
  5912 
  5913 * Bali: Java source language formalization. Type system, operational
  5914 semantics, axiomatic semantics. Supported language features:
  5915 classes, interfaces, objects,virtual methods, static methods,
  5916 static/instance fields, arrays, access modifiers, definite
  5917 assignment, exceptions.
  5918 
  5919 
  5920 *** ZF ***
  5921 
  5922 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  5923 universe, etc.);
  5924 
  5925 * Main ZF: virtually all theories converted to new-style format;
  5926 
  5927 
  5928 *** ML ***
  5929 
  5930 * Pure: Tactic.prove provides sane interface for internal proofs;
  5931 omits the infamous "standard" operation, so this is more appropriate
  5932 than prove_goalw_cterm in many situations (e.g. in simprocs);
  5933 
  5934 * Pure: improved error reporting of simprocs;
  5935 
  5936 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  5937 up simprocs;
  5938 
  5939 
  5940 *** Document preparation ***
  5941 
  5942 * uses \par instead of \\ for line breaks in theory text. This may
  5943 shift some page breaks in large documents. To get the old behaviour
  5944 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  5945 
  5946 * minimized dependencies of isabelle.sty and isabellesym.sty on
  5947 other packages
  5948 
  5949 * \<euro> now needs package babel/greek instead of marvosym (which
  5950 broke \Rightarrow)
  5951 
  5952 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  5953 textcomp package)
  5954 
  5955 
  5956 
  5957 New in Isabelle2002 (March 2002)
  5958 --------------------------------
  5959 
  5960 *** Document preparation ***
  5961 
  5962 * greatly simplified document preparation setup, including more
  5963 graceful interpretation of isatool usedir -i/-d/-D options, and more
  5964 instructive isatool mkdir; users should basically be able to get
  5965 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  5966 users may run a separate document processing stage manually like this:
  5967 "isatool usedir -D output HOL Test && isatool document Test/output";
  5968 
  5969 * theory dependency graph may now be incorporated into documents;
  5970 isatool usedir -g true will produce session_graph.eps/.pdf for use
  5971 with \includegraphics of LaTeX;
  5972 
  5973 * proper spacing of consecutive markup elements, especially text
  5974 blocks after section headings;
  5975 
  5976 * support bold style (for single symbols only), input syntax is like
  5977 this: "\<^bold>\<alpha>" or "\<^bold>A";
  5978 
  5979 * \<bullet> is now output as bold \cdot by default, which looks much
  5980 better in printed text;
  5981 
  5982 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  5983 note that these symbols are currently unavailable in Proof General /
  5984 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  5985 
  5986 * isatool latex no longer depends on changed TEXINPUTS, instead
  5987 isatool document copies the Isabelle style files to the target
  5988 location;
  5989 
  5990 
  5991 *** Isar ***
  5992 
  5993 * Pure/Provers: improved proof by cases and induction;
  5994   - 'case' command admits impromptu naming of parameters (such as
  5995     "case (Suc n)");
  5996   - 'induct' method divinates rule instantiation from the inductive
  5997     claim; no longer requires excessive ?P bindings for proper
  5998     instantiation of cases;
  5999   - 'induct' method properly enumerates all possibilities of set/type
  6000     rules; as a consequence facts may be also passed through *type*
  6001     rules without further ado;
  6002   - 'induct' method now derives symbolic cases from the *rulified*
  6003     rule (before it used to rulify cases stemming from the internal
  6004     atomized version); this means that the context of a non-atomic
  6005     statement becomes is included in the hypothesis, avoiding the
  6006     slightly cumbersome show "PROP ?case" form;
  6007   - 'induct' may now use elim-style induction rules without chaining
  6008     facts, using ``missing'' premises from the goal state; this allows
  6009     rules stemming from inductive sets to be applied in unstructured
  6010     scripts, while still benefitting from proper handling of non-atomic
  6011     statements; NB: major inductive premises need to be put first, all
  6012     the rest of the goal is passed through the induction;
  6013   - 'induct' proper support for mutual induction involving non-atomic
  6014     rule statements (uses the new concept of simultaneous goals, see
  6015     below);
  6016   - append all possible rule selections, but only use the first
  6017     success (no backtracking);
  6018   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  6019   - undeclared rule case names default to numbers 1, 2, 3, ...;
  6020   - added 'print_induct_rules' (covered by help item in recent Proof
  6021     General versions);
  6022   - moved induct/cases attributes to Pure, methods to Provers;
  6023   - generic method setup instantiated for FOL and HOL;
  6024 
  6025 * Pure: support multiple simultaneous goal statements, for example
  6026 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  6027 meta-level mechanism, this acts as if several individual goals had
  6028 been stated separately; in particular common proof methods need to be
  6029 repeated in order to cover all claims; note that a single elimination
  6030 step is *not* sufficient to establish the two conjunctions, so this
  6031 fails:
  6032 
  6033   assume "A & B" then have A and B ..   (*".." fails*)
  6034 
  6035 better use "obtain" in situations as above; alternative refer to
  6036 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  6037 
  6038 * Pure: proper integration with ``locales''; unlike the original
  6039 version by Florian Kammller, Isar locales package high-level proof
  6040 contexts rather than raw logical ones (e.g. we admit to include
  6041 attributes everywhere); operations on locales include merge and
  6042 rename; support for implicit arguments (``structures''); simultaneous
  6043 type-inference over imports and text; see also HOL/ex/Locales.thy for
  6044 some examples;
  6045 
  6046 * Pure: the following commands have been ``localized'', supporting a
  6047 target locale specification "(in name)": 'lemma', 'theorem',
  6048 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  6049 stored both within the locale and at the theory level (exported and
  6050 qualified by the locale name);
  6051 
  6052 * Pure: theory goals may now be specified in ``long'' form, with
  6053 ad-hoc contexts consisting of arbitrary locale elements. for example
  6054 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  6055 definitions may be given, too); the result is a meta-level rule with
  6056 the context elements being discharged in the obvious way;
  6057 
  6058 * Pure: new proof command 'using' allows to augment currently used
  6059 facts after a goal statement ('using' is syntactically analogous to
  6060 'apply', but acts on the goal's facts only); this allows chained facts
  6061 to be separated into parts given before and after a claim, as in
  6062 ``from a and b have C using d and e <proof>'';
  6063 
  6064 * Pure: renamed "antecedent" case to "rule_context";
  6065 
  6066 * Pure: new 'judgment' command records explicit information about the
  6067 object-logic embedding (used by several tools internally); no longer
  6068 use hard-wired "Trueprop";
  6069 
  6070 * Pure: added 'corollary' command;
  6071 
  6072 * Pure: fixed 'token_translation' command;
  6073 
  6074 * Pure: removed obsolete 'exported' attribute;
  6075 
  6076 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  6077 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  6078 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  6079 
  6080 * Pure: method 'atomize' presents local goal premises as object-level
  6081 statements (atomic meta-level propositions); setup controlled via
  6082 rewrite rules declarations of 'atomize' attribute; example
  6083 application: 'induct' method with proper rule statements in improper
  6084 proof *scripts*;
  6085 
  6086 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  6087 now consider the syntactic context of assumptions, giving a better
  6088 chance to get type-inference of the arguments right (this is
  6089 especially important for locales);
  6090 
  6091 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  6092 mode;
  6093 
  6094 * Pure/obtain: the formal conclusion "thesis", being marked as
  6095 ``internal'', may no longer be reference directly in the text;
  6096 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  6097 situations;
  6098 
  6099 * Pure: generic 'sym' attribute which declares a rule both as pure
  6100 'elim?' and for the 'symmetric' operation;
  6101 
  6102 * Pure: marginal comments ``--'' may now occur just anywhere in the
  6103 text; the fixed correlation with particular command syntax has been
  6104 discontinued;
  6105 
  6106 * Pure: new method 'rules' is particularly well-suited for proof
  6107 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  6108 but often produces more compact proof terms with less detours;
  6109 
  6110 * Pure/Provers/classical: simplified integration with pure rule
  6111 attributes and methods; the classical "intro?/elim?/dest?"
  6112 declarations coincide with the pure ones; the "rule" method no longer
  6113 includes classically swapped intros; "intro" and "elim" methods no
  6114 longer pick rules from the context; also got rid of ML declarations
  6115 AddXIs/AddXEs/AddXDs; all of this has some potential for
  6116 INCOMPATIBILITY;
  6117 
  6118 * Provers/classical: attribute 'swapped' produces classical inversions
  6119 of introduction rules;
  6120 
  6121 * Provers/simplifier: 'simplified' attribute may refer to explicit
  6122 rules instead of full simplifier context; 'iff' attribute handles
  6123 conditional rules;
  6124 
  6125 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  6126 
  6127 * HOL: 'recdef' now fails on unfinished automated proofs, use
  6128 "(permissive)" option to recover old behavior;
  6129 
  6130 * HOL: 'inductive' no longer features separate (collective) attributes
  6131 for 'intros' (was found too confusing);
  6132 
  6133 * HOL: properly declared induction rules less_induct and
  6134 wf_induct_rule;
  6135 
  6136 
  6137 *** HOL ***
  6138 
  6139 * HOL: moved over to sane numeral syntax; the new policy is as
  6140 follows:
  6141 
  6142   - 0 and 1 are polymorphic constants, which are defined on any
  6143   numeric type (nat, int, real etc.);
  6144 
  6145   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  6146   binary representation internally;
  6147 
  6148   - type nat has special constructor Suc, and generally prefers Suc 0
  6149   over 1::nat and Suc (Suc 0) over 2::nat;
  6150 
  6151 This change may cause significant problems of INCOMPATIBILITY; here
  6152 are some hints on converting existing sources:
  6153 
  6154   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  6155   entities, so expressions involving "-" (unary or binary minus) need
  6156   to be spaced properly;
  6157 
  6158   - existing occurrences of "1" may need to be constraint "1::nat" or
  6159   even replaced by Suc 0; similar for old "2";
  6160 
  6161   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  6162 
  6163   - remove all special provisions on numerals in proofs;
  6164 
  6165 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  6166 representation (depends on bin_arith_simps in the default context);
  6167 
  6168 * HOL: symbolic syntax for x^2 (numeral 2);
  6169 
  6170 * HOL: the class of all HOL types is now called "type" rather than
  6171 "term"; INCOMPATIBILITY, need to adapt references to this type class
  6172 in axclass/classes, instance/arities, and (usually rare) occurrences
  6173 in typings (of consts etc.); internally the class is called
  6174 "HOL.type", ML programs should refer to HOLogic.typeS;
  6175 
  6176 * HOL/record package improvements:
  6177   - new derived operations "fields" to build a partial record section,
  6178     "extend" to promote a fixed record to a record scheme, and
  6179     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  6180     declared as simp by default;
  6181   - shared operations ("more", "fields", etc.) now need to be always
  6182     qualified) --- potential INCOMPATIBILITY;
  6183   - removed "make_scheme" operations (use "make" with "extend") --
  6184     INCOMPATIBILITY;
  6185   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  6186   - provides cases/induct rules for use with corresponding Isar
  6187     methods (for concrete records, record schemes, concrete more
  6188     parts, and schematic more parts -- in that order);
  6189   - internal definitions directly based on a light-weight abstract
  6190     theory of product types over typedef rather than datatype;
  6191 
  6192 * HOL: generic code generator for generating executable ML code from
  6193 specifications; specific support for HOL constructs such as inductive
  6194 datatypes and sets, as well as recursive functions; can be invoked
  6195 via 'generate_code' theory section;
  6196 
  6197 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  6198 
  6199 * HOL: consolidated and renamed several theories.  In particular:
  6200         Ord.thy has been absorbed into HOL.thy
  6201         String.thy has been absorbed into List.thy
  6202 
  6203 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  6204 (beware of argument permutation!);
  6205 
  6206 * HOL: linorder_less_split superseded by linorder_cases;
  6207 
  6208 * HOL/List: "nodups" renamed to "distinct";
  6209 
  6210 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  6211 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  6212   - Ex_def has changed, now need to use some_eq_ex
  6213 
  6214 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  6215 in this (rare) case use:
  6216 
  6217   delSWrapper "split_all_tac"
  6218   addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
  6219 
  6220 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
  6221 MAY FAIL;
  6222 
  6223 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
  6224 Isabelle's type classes, ^ on functions and relations has too general
  6225 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be
  6226 necessary to attach explicit type constraints;
  6227 
  6228 * HOL/Relation: the prefix name of the infix "O" has been changed from
  6229 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been