NEWS
author wenzelm
Tue May 03 22:27:32 2011 +0200 (2011-05-03)
changeset 42669 04dfffda5671
parent 42658 8f5d5d71add0
child 42706 936cd1c493b4
permissions -rw-r--r--
more conventional naming scheme: names_long, names_short, names_unique;
     1 Isabelle NEWS -- history user-relevant changes
     2 ==============================================
     3 
     4 New in this Isabelle version
     5 ----------------------------
     6 
     7 *** General ***
     8 
     9 * Theory loader: source files are identified by content via SHA1
    10 digests.  Discontinued former path/modtime identification and optional
    11 ISABELLE_FILE_IDENT plugin scripts.
    12 
    13 * Parallelization of nested Isar proofs is subject to
    14 Goal.parallel_proofs_threshold (default 100).  See also isabelle
    15 usedir option -Q.
    16 
    17 * Discontinued support for Poly/ML 5.2, which was the last version
    18 without proper multithreading and TimeLimit implementation.
    19 
    20 * Discontinued old lib/scripts/polyml-platform, which has been
    21 obsolete since Isabelle2009-2.
    22 
    23 * Theory loader: source files are exclusively located via the master
    24 directory of each theory node (where the .thy file itself resides).
    25 The global load path (such as src/HOL/Library) is has been
    26 discontinued.  INCOMPATIBILITY.
    27 
    28 * Various optional external tools are referenced more robustly and
    29 uniformly by explicit Isabelle settings as follows:
    30 
    31   ISABELLE_CSDP   (formerly CSDP_EXE)
    32   ISABELLE_GHC    (formerly EXEC_GHC or GHC_PATH)
    33   ISABELLE_OCAML  (formerly EXEC_OCAML)
    34   ISABELLE_SWIPL  (formerly EXEC_SWIPL)
    35   ISABELLE_YAP    (formerly EXEC_YAP)
    36 
    37 Note that automated detection from the file-system or search path has
    38 been discontinued.  INCOMPATIBILITY.
    39 
    40 * Name space: former unsynchronized references are now proper
    41 configuration options, with more conventional names:
    42 
    43   long_names   ~> names_long
    44   short_names  ~> names_short
    45   unique_names ~> names_unique
    46 
    47 Minor INCOMPATIBILITY, need to declare options in context like this:
    48 
    49   declare [[names_unique = false]]
    50 
    51 * Literal facts `prop` may contain dummy patterns, e.g. `_ = _`.  Note
    52 that the result needs to be unique, which means fact specifications
    53 may have to be refined after enriching a proof context.
    54 
    55 * Isabelle/Isar reference manual provides more formal references in
    56 syntax diagrams.
    57 
    58 
    59 *** HOL ***
    60 
    61 * Nitpick:
    62   - Added "need" and "total_consts" options.
    63   - Reintroduced "show_skolems" option by popular demand.
    64   - Renamed attribute: nitpick_def ~> nitpick_unfold.
    65     INCOMPATIBILITY.
    66 
    67 * Sledgehammer:
    68   - sledgehammer available_provers ~> sledgehammer supported_provers
    69     INCOMPATIBILITY.
    70   - Added support for SNARK and ToFoF-E on SystemOnTPTP and for simply typed
    71     TPTP problems (TFF).
    72   - Added "type_sys" and "monomorphize_limit" options.
    73 
    74 * "try":
    75   - Added "simp:", "intro:", and "elim:" options.
    76 
    77 * Quickcheck:
    78   - Added "eval" option to evaluate terms for the found counterexample
    79     (currently only supported by the default (exhaustive) tester)
    80   - Added post-processing of terms to obtain readable counterexamples
    81     (currently only supported by the default (exhaustive) tester)
    82 
    83 * Function package: discontinued option "tailrec".
    84 INCOMPATIBILITY. Use partial_function instead.
    85 
    86 * HOL-Probability:
    87   - Caratheodory's extension lemma is now proved for ring_of_sets.
    88   - Infinite products of probability measures are now available.
    89   - Use extended reals instead of positive extended reals.
    90     INCOMPATIBILITY.
    91 
    92 
    93 *** Document preparation ***
    94 
    95 * Antiquotation @{rail} layouts railroad syntax diagrams; requires
    96 railsetup.sty included in the Isabelle distribution; see also isar-ref
    97 manual.
    98 
    99 * Localized \isabellestyle switch can be used within blocks or groups
   100 like this:
   101 
   102   \isabellestyle{it}  %preferred default
   103   {\isabellestylett @{text "typewriter stuff"}}
   104 
   105 * New term style "isub" as ad-hoc conversion of variables x1, y23 into
   106 subscripted form x\<^isub>1, y\<^isub>2\<^isub>3.
   107 
   108 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
   109 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
   110 
   111 
   112 *** ML ***
   113 
   114 * Structure Proof_Context follows standard naming scheme.  Old
   115 ProofContext is still available for some time as legacy alias.
   116 
   117 * Structure Timing provides various operations for timing; supersedes
   118 former start_timing/end_timing etc.
   119 
   120 * Path.print is the official way to show file-system paths to users
   121 (including quotes etc.).
   122 
   123 * Inner syntax: identifiers in parse trees of generic categories
   124 "logic", "aprop", "idt" etc. carry position information (disguised as
   125 type constraints).  Occasional INCOMPATIBILITY with non-compliant
   126 translations that choke on unexpected type constraints.  Positions can
   127 be stripped in ML translations via Syntax.strip_positions /
   128 Syntax.strip_positions_ast, or via the syntax constant
   129 "_strip_positions" within parse trees.  As last resort, positions can
   130 be disabled via the configuration option Syntax.positions, which is
   131 called "syntax_positions" in Isar attribute syntax.
   132 
   133 * Discontinued special status of various ML structures that contribute
   134 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
   135 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
   136 refer directly to Ast.Constant, Lexicon.is_identifier,
   137 Syntax_Trans.mk_binder_tr etc.
   138 
   139 * Typed print translation: discontinued show_sorts argument, which is
   140 already available via context of "advanced" translation.
   141 
   142 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
   143 goal states; body tactic needs to address all subgoals uniformly.
   144 
   145 * Slightly more special eq_list/eq_set, with shortcut involving
   146 pointer equality (assumes that eq relation is reflexive).
   147 
   148 
   149 
   150 New in Isabelle2011 (January 2011)
   151 ----------------------------------
   152 
   153 *** General ***
   154 
   155 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
   156 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
   157 useful tooltips and hyperlinks produced from its static analysis.  The
   158 bundled component provides an executable Isabelle tool that can be run
   159 like this:
   160 
   161   Isabelle2011/bin/isabelle jedit
   162 
   163 * Significantly improved Isabelle/Isar implementation manual.
   164 
   165 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
   166 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
   167 while the default heap location within that directory lacks that extra
   168 suffix.  This isolates multiple Isabelle installations from each
   169 other, avoiding problems with old settings in new versions.
   170 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
   171 
   172 * Source files are always encoded as UTF-8, instead of old-fashioned
   173 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   174 the following package declarations:
   175 
   176   \usepackage[utf8]{inputenc}
   177   \usepackage{textcomp}
   178 
   179 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   180 a Unicode character is treated as a single symbol, not a sequence of
   181 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   182 contain symbols without further backslash escapes, Unicode can now be
   183 used here as well.  Recall that Symbol.explode in ML provides a
   184 consistent view on symbols, while raw explode (or String.explode)
   185 merely give a byte-oriented representation.
   186 
   187 * Theory loader: source files are primarily located via the master
   188 directory of each theory node (where the .thy file itself resides).
   189 The global load path is still partially available as legacy feature.
   190 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   191 explicit paths, relatively to the theory.
   192 
   193 * Special treatment of ML file names has been discontinued.
   194 Historically, optional extensions .ML or .sml were added on demand --
   195 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   196 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   197 
   198 * Various options that affect pretty printing etc. are now properly
   199 handled within the context via configuration options, instead of
   200 unsynchronized references or print modes.  There are both ML Config.T
   201 entities and Isar declaration attributes to access these.
   202 
   203   ML (Config.T)                 Isar (attribute)
   204 
   205   eta_contract                  eta_contract
   206   show_brackets                 show_brackets
   207   show_sorts                    show_sorts
   208   show_types                    show_types
   209   show_question_marks           show_question_marks
   210   show_consts                   show_consts
   211   show_abbrevs                  show_abbrevs
   212 
   213   Syntax.ast_trace              syntax_ast_trace
   214   Syntax.ast_stat               syntax_ast_stat
   215   Syntax.ambiguity_level        syntax_ambiguity_level
   216 
   217   Goal_Display.goals_limit      goals_limit
   218   Goal_Display.show_main_goal   show_main_goal
   219 
   220   Method.rule_trace             rule_trace
   221 
   222   Thy_Output.display            thy_output_display
   223   Thy_Output.quotes             thy_output_quotes
   224   Thy_Output.indent             thy_output_indent
   225   Thy_Output.source             thy_output_source
   226   Thy_Output.break              thy_output_break
   227 
   228 Note that corresponding "..._default" references in ML may only be
   229 changed globally at the ROOT session setup, but *not* within a theory.
   230 The option "show_abbrevs" supersedes the former print mode
   231 "no_abbrevs" with inverted meaning.
   232 
   233 * More systematic naming of some configuration options.
   234 INCOMPATIBILITY.
   235 
   236   trace_simp  ~>  simp_trace
   237   debug_simp  ~>  simp_debug
   238 
   239 * Support for real valued configuration options, using simplistic
   240 floating-point notation that coincides with the inner syntax for
   241 float_token.
   242 
   243 * Support for real valued preferences (with approximative PGIP type):
   244 front-ends need to accept "pgint" values in float notation.
   245 INCOMPATIBILITY.
   246 
   247 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   248 DejaVu Sans.
   249 
   250 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   251 
   252 
   253 *** Pure ***
   254 
   255 * Command 'type_synonym' (with single argument) replaces somewhat
   256 outdated 'types', which is still available as legacy feature for some
   257 time.
   258 
   259 * Command 'nonterminal' (with 'and' separated list of arguments)
   260 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   261 
   262 * Command 'notepad' replaces former 'example_proof' for
   263 experimentation in Isar without any result.  INCOMPATIBILITY.
   264 
   265 * Locale interpretation commands 'interpret' and 'sublocale' accept
   266 lists of equations to map definitions in a locale to appropriate
   267 entities in the context of the interpretation.  The 'interpretation'
   268 command already provided this functionality.
   269 
   270 * Diagnostic command 'print_dependencies' prints the locale instances
   271 that would be activated if the specified expression was interpreted in
   272 the current context.  Variant "print_dependencies!" assumes a context
   273 without interpretations.
   274 
   275 * Diagnostic command 'print_interps' prints interpretations in proofs
   276 in addition to interpretations in theories.
   277 
   278 * Discontinued obsolete 'global' and 'local' commands to manipulate
   279 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   280 Sign.root_path and Sign.local_path may be applied directly where this
   281 feature is still required for historical reasons.
   282 
   283 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   284 'definition' instead.
   285 
   286 * The "prems" fact, which refers to the accidental collection of
   287 foundational premises in the context, is now explicitly marked as
   288 legacy feature and will be discontinued soon.  Consider using "assms"
   289 of the head statement or reference facts by explicit names.
   290 
   291 * Document antiquotations @{class} and @{type} print classes and type
   292 constructors.
   293 
   294 * Document antiquotation @{file} checks file/directory entries within
   295 the local file system.
   296 
   297 
   298 *** HOL ***
   299 
   300 * Coercive subtyping: functions can be declared as coercions and type
   301 inference will add them as necessary upon input of a term.  Theory
   302 Complex_Main declares real :: nat => real and real :: int => real as
   303 coercions. A coercion function f is declared like this:
   304 
   305   declare [[coercion f]]
   306 
   307 To lift coercions through type constructors (e.g. from nat => real to
   308 nat list => real list), map functions can be declared, e.g.
   309 
   310   declare [[coercion_map map]]
   311 
   312 Currently coercion inference is activated only in theories including
   313 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   314 the configuration option "coercion_enabled", e.g. it can be enabled in
   315 other theories like this:
   316 
   317   declare [[coercion_enabled]]
   318 
   319 * Command 'partial_function' provides basic support for recursive
   320 function definitions over complete partial orders.  Concrete instances
   321 are provided for i) the option type, ii) tail recursion on arbitrary
   322 types, and iii) the heap monad of Imperative_HOL.  See
   323 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   324 for examples.
   325 
   326 * Function package: f.psimps rules are no longer implicitly declared
   327 as [simp].  INCOMPATIBILITY.
   328 
   329 * Datatype package: theorems generated for executable equality (class
   330 "eq") carry proper names and are treated as default code equations.
   331 
   332 * Inductive package: now offers command 'inductive_simps' to
   333 automatically derive instantiated and simplified equations for
   334 inductive predicates, similar to 'inductive_cases'.
   335 
   336 * Command 'enriched_type' allows to register properties of the
   337 functorial structure of types.
   338 
   339 * Improved infrastructure for term evaluation using code generator
   340 techniques, in particular static evaluation conversions.
   341 
   342 * Code generator: Scala (2.8 or higher) has been added to the target
   343 languages.
   344 
   345 * Code generator: globbing constant expressions "*" and "Theory.*"
   346 have been replaced by the more idiomatic "_" and "Theory._".
   347 INCOMPATIBILITY.
   348 
   349 * Code generator: export_code without explicit file declaration prints
   350 to standard output.  INCOMPATIBILITY.
   351 
   352 * Code generator: do not print function definitions for case
   353 combinators any longer.
   354 
   355 * Code generator: simplification with rules determined with
   356 src/Tools/Code/code_simp.ML and method "code_simp".
   357 
   358 * Code generator for records: more idiomatic representation of record
   359 types.  Warning: records are not covered by ancient SML code
   360 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   361 rep_datatype declaration helps to succeed then:
   362 
   363   record 'a foo = ...
   364   ...
   365   rep_datatype foo_ext ...
   366 
   367 * Records: logical foundation type for records does not carry a
   368 '_type' suffix any longer (obsolete due to authentic syntax).
   369 INCOMPATIBILITY.
   370 
   371 * Quickcheck now by default uses exhaustive testing instead of random
   372 testing.  Random testing can be invoked by "quickcheck [random]",
   373 exhaustive testing by "quickcheck [exhaustive]".
   374 
   375 * Quickcheck instantiates polymorphic types with small finite
   376 datatypes by default. This enables a simple execution mechanism to
   377 handle quantifiers and function equality over the finite datatypes.
   378 
   379 * Quickcheck random generator has been renamed from "code" to
   380 "random".  INCOMPATIBILITY.
   381 
   382 * Quickcheck now has a configurable time limit which is set to 30
   383 seconds by default. This can be changed by adding [timeout = n] to the
   384 quickcheck command. The time limit for Auto Quickcheck is still set
   385 independently.
   386 
   387 * Quickcheck in locales considers interpretations of that locale for
   388 counter example search.
   389 
   390 * Sledgehammer:
   391   - Added "smt" and "remote_smt" provers based on the "smt" proof
   392     method. See the Sledgehammer manual for details ("isabelle doc
   393     sledgehammer").
   394   - Renamed commands:
   395     sledgehammer atp_info ~> sledgehammer running_provers
   396     sledgehammer atp_kill ~> sledgehammer kill_provers
   397     sledgehammer available_atps ~> sledgehammer available_provers
   398     INCOMPATIBILITY.
   399   - Renamed options:
   400     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   401     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   402     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   403     (and "ms" and "min" are no longer supported)
   404     INCOMPATIBILITY.
   405 
   406 * Nitpick:
   407   - Renamed options:
   408     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   409     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   410     INCOMPATIBILITY.
   411   - Added support for partial quotient types.
   412   - Added local versions of the "Nitpick.register_xxx" functions.
   413   - Added "whack" option.
   414   - Allow registration of quotient types as codatatypes.
   415   - Improved "merge_type_vars" option to merge more types.
   416   - Removed unsound "fast_descrs" option.
   417   - Added custom symmetry breaking for datatypes, making it possible to reach
   418     higher cardinalities.
   419   - Prevent the expansion of too large definitions.
   420 
   421 * Proof methods "metis" and "meson" now have configuration options
   422 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   423 to diagnose these tools. E.g.
   424 
   425     using [[metis_trace = true]]
   426 
   427 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   428 manually as command 'solve_direct'.
   429 
   430 * The default SMT solver Z3 must be enabled explicitly (due to
   431 licensing issues) by setting the environment variable
   432 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   433 commercial applications, the SMT solver CVC3 is provided as fall-back;
   434 changing the SMT solver is done via the configuration option
   435 "smt_solver".
   436 
   437 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   438 i.e. "remote_cvc3" and "remote_z3".
   439 
   440 * Added basic SMT support for datatypes, records, and typedefs using
   441 the oracle mode (no proofs).  Direct support of pairs has been dropped
   442 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   443 support for a similar behavior).  Minor INCOMPATIBILITY.
   444 
   445 * Changed SMT configuration options:
   446   - Renamed:
   447     z3_proofs ~> smt_oracle (with inverted meaning)
   448     z3_trace_assms ~> smt_trace_used_facts
   449     INCOMPATIBILITY.
   450   - Added:
   451     smt_verbose
   452     smt_random_seed
   453     smt_datatypes
   454     smt_infer_triggers
   455     smt_monomorph_limit
   456     cvc3_options
   457     remote_cvc3_options
   458     remote_z3_options
   459     yices_options
   460 
   461 * Boogie output files (.b2i files) need to be declared in the theory
   462 header.
   463 
   464 * Simplification procedure "list_to_set_comprehension" rewrites list
   465 comprehensions applied to List.set to set comprehensions.  Occasional
   466 INCOMPATIBILITY, may be deactivated like this:
   467 
   468   declare [[simproc del: list_to_set_comprehension]]
   469 
   470 * Removed old version of primrec package.  INCOMPATIBILITY.
   471 
   472 * Removed simplifier congruence rule of "prod_case", as has for long
   473 been the case with "split".  INCOMPATIBILITY.
   474 
   475 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   476 
   477 * Removed [split_format ... and ... and ...] version of
   478 [split_format].  Potential INCOMPATIBILITY.
   479 
   480 * Predicate "sorted" now defined inductively, with nice induction
   481 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   482 
   483 * Constant "contents" renamed to "the_elem", to free the generic name
   484 contents for other uses.  INCOMPATIBILITY.
   485 
   486 * Renamed class eq and constant eq (for code generation) to class
   487 equal and constant equal, plus renaming of related facts and various
   488 tuning.  INCOMPATIBILITY.
   489 
   490 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   491 
   492 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   493 INCOMPATIBILITY.
   494 
   495 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   496 avoid confusion with finite sets.  INCOMPATIBILITY.
   497 
   498 * Abandoned locales equiv, congruent and congruent2 for equivalence
   499 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   500 for congruent(2)).
   501 
   502 * Some previously unqualified names have been qualified:
   503 
   504   types
   505     bool ~> HOL.bool
   506     nat ~> Nat.nat
   507 
   508   constants
   509     Trueprop ~> HOL.Trueprop
   510     True ~> HOL.True
   511     False ~> HOL.False
   512     op & ~> HOL.conj
   513     op | ~> HOL.disj
   514     op --> ~> HOL.implies
   515     op = ~> HOL.eq
   516     Not ~> HOL.Not
   517     The ~> HOL.The
   518     All ~> HOL.All
   519     Ex ~> HOL.Ex
   520     Ex1 ~> HOL.Ex1
   521     Let ~> HOL.Let
   522     If ~> HOL.If
   523     Ball ~> Set.Ball
   524     Bex ~> Set.Bex
   525     Suc ~> Nat.Suc
   526     Pair ~> Product_Type.Pair
   527     fst ~> Product_Type.fst
   528     snd ~> Product_Type.snd
   529     curry ~> Product_Type.curry
   530     op : ~> Set.member
   531     Collect ~> Set.Collect
   532 
   533 INCOMPATIBILITY.
   534 
   535 * More canonical naming convention for some fundamental definitions:
   536 
   537     bot_bool_eq ~> bot_bool_def
   538     top_bool_eq ~> top_bool_def
   539     inf_bool_eq ~> inf_bool_def
   540     sup_bool_eq ~> sup_bool_def
   541     bot_fun_eq  ~> bot_fun_def
   542     top_fun_eq  ~> top_fun_def
   543     inf_fun_eq  ~> inf_fun_def
   544     sup_fun_eq  ~> sup_fun_def
   545 
   546 INCOMPATIBILITY.
   547 
   548 * More stylized fact names:
   549 
   550   expand_fun_eq ~> fun_eq_iff
   551   expand_set_eq ~> set_eq_iff
   552   set_ext       ~> set_eqI
   553   nat_number    ~> eval_nat_numeral
   554 
   555 INCOMPATIBILITY.
   556 
   557 * Refactoring of code-generation specific operations in theory List:
   558 
   559   constants
   560     null ~> List.null
   561 
   562   facts
   563     mem_iff ~> member_def
   564     null_empty ~> null_def
   565 
   566 INCOMPATIBILITY.  Note that these were not supposed to be used
   567 regularly unless for striking reasons; their main purpose was code
   568 generation.
   569 
   570 Various operations from the Haskell prelude are used for generating
   571 Haskell code.
   572 
   573 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   574 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   575 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   576 
   577 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   578 "*" and "+" respectively.  INCOMPATIBILITY.
   579 
   580 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   581 "Sum_Type.Plus" instead.
   582 
   583 * Constant "split" has been merged with constant "prod_case"; names of
   584 ML functions, facts etc. involving split have been retained so far,
   585 though.  INCOMPATIBILITY.
   586 
   587 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   588 instead.  INCOMPATIBILITY.
   589 
   590 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   591 INCOMPATIBILITY.
   592 
   593 * Former theory Library/Enum is now part of the HOL-Main image.
   594 INCOMPATIBILITY: all constants of the Enum theory now have to be
   595 referred to by its qualified name.
   596 
   597   enum    ~>  Enum.enum
   598   nlists  ~>  Enum.nlists
   599   product ~>  Enum.product
   600 
   601 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   602 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   603 INCOMPATIBILITY.
   604 
   605 * Theory Library/SetsAndFunctions has been split into
   606 Library/Function_Algebras and Library/Set_Algebras; canonical names
   607 for instance definitions for functions; various improvements.
   608 INCOMPATIBILITY.
   609 
   610 * Theory Library/Multiset provides stable quicksort implementation of
   611 sort_key.
   612 
   613 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   614 INCOMPATIBILITY.
   615 
   616 * Session Multivariate_Analysis: introduced a type class for euclidean
   617 space.  Most theorems are now stated in terms of euclidean spaces
   618 instead of finite cartesian products.
   619 
   620   types
   621     real ^ 'n ~>  'a::real_vector
   622               ~>  'a::euclidean_space
   623               ~>  'a::ordered_euclidean_space
   624         (depends on your needs)
   625 
   626   constants
   627      _ $ _        ~> _ $$ _
   628      \<chi> x. _  ~> \<chi>\<chi> x. _
   629      CARD('n)     ~> DIM('a)
   630 
   631 Also note that the indices are now natural numbers and not from some
   632 finite type. Finite cartesian products of euclidean spaces, products
   633 of euclidean spaces the real and complex numbers are instantiated to
   634 be euclidean_spaces.  INCOMPATIBILITY.
   635 
   636 * Session Probability: introduced pextreal as positive extended real
   637 numbers.  Use pextreal as value for measures.  Introduce the
   638 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   639 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   640 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   641 
   642 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   643 INCOMPATIBILITY.
   644 
   645 * Session SPARK (with image HOL-SPARK) provides commands to load and
   646 prove verification conditions generated by the SPARK Ada program
   647 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   648 
   649 
   650 *** HOL-Algebra ***
   651 
   652 * Theorems for additive ring operations (locale abelian_monoid and
   653 descendants) are generated by interpretation from their multiplicative
   654 counterparts.  Names (in particular theorem names) have the mandatory
   655 qualifier 'add'.  Previous theorem names are redeclared for
   656 compatibility.
   657 
   658 * Structure "int_ring" is now an abbreviation (previously a
   659 definition).  This fits more natural with advanced interpretations.
   660 
   661 
   662 *** HOLCF ***
   663 
   664 * The domain package now runs in definitional mode by default: The
   665 former command 'new_domain' is now called 'domain'.  To use the domain
   666 package in its original axiomatic mode, use 'domain (unsafe)'.
   667 INCOMPATIBILITY.
   668 
   669 * The new class "domain" is now the default sort.  Class "predomain"
   670 is an unpointed version of "domain". Theories can be updated by
   671 replacing sort annotations as shown below.  INCOMPATIBILITY.
   672 
   673   'a::type ~> 'a::countable
   674   'a::cpo  ~> 'a::predomain
   675   'a::pcpo ~> 'a::domain
   676 
   677 * The old type class "rep" has been superseded by class "domain".
   678 Accordingly, users of the definitional package must remove any
   679 "default_sort rep" declarations.  INCOMPATIBILITY.
   680 
   681 * The domain package (definitional mode) now supports unpointed
   682 predomain argument types, as long as they are marked 'lazy'. (Strict
   683 arguments must be in class "domain".) For example, the following
   684 domain definition now works:
   685 
   686   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   687 
   688 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   689 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   690 'a option, and 'a list.  Additionally, it configures fixrec and the
   691 domain package to work with these types.  For example:
   692 
   693   fixrec isInl :: "('a + 'b) u -> tr"
   694     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   695 
   696   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   697 
   698 * The "(permissive)" option of fixrec has been replaced with a
   699 per-equation "(unchecked)" option. See
   700 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
   701 
   702 * The "bifinite" class no longer fixes a constant "approx"; the class
   703 now just asserts that such a function exists.  INCOMPATIBILITY.
   704 
   705 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
   706 defines an embedding of type 'a defl into udom by default; instances
   707 of "bifinite" and "domain" classes are available in
   708 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
   709 
   710 * The syntax "REP('a)" has been replaced with "DEFL('a)".
   711 
   712 * The predicate "directed" has been removed.  INCOMPATIBILITY.
   713 
   714 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
   715 
   716 * The function "cprod_map" has been renamed to "prod_map".
   717 INCOMPATIBILITY.
   718 
   719 * The monadic bind operator on each powerdomain has new binder syntax
   720 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
   721 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
   722 
   723 * The infix syntax for binary union on each powerdomain has changed
   724 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
   725 syntax.  INCOMPATIBILITY.
   726 
   727 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
   728 still supported as an input translation.
   729 
   730 * Renamed some theorems (the original names are also still available).
   731 
   732   expand_fun_below   ~> fun_below_iff
   733   below_fun_ext      ~> fun_belowI
   734   expand_cfun_eq     ~> cfun_eq_iff
   735   ext_cfun           ~> cfun_eqI
   736   expand_cfun_below  ~> cfun_below_iff
   737   below_cfun_ext     ~> cfun_belowI
   738   cont2cont_Rep_CFun ~> cont2cont_APP
   739 
   740 * The Abs and Rep functions for various types have changed names.
   741 Related theorem names have also changed to match. INCOMPATIBILITY.
   742 
   743   Rep_CFun  ~> Rep_cfun
   744   Abs_CFun  ~> Abs_cfun
   745   Rep_Sprod ~> Rep_sprod
   746   Abs_Sprod ~> Abs_sprod
   747   Rep_Ssum  ~> Rep_ssum
   748   Abs_Ssum  ~> Abs_ssum
   749 
   750 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   751 been renamed to *_bottom_iff.  INCOMPATIBILITY.
   752 
   753 * Various changes to bisimulation/coinduction with domain package:
   754 
   755   - Definitions of "bisim" constants no longer mention definedness.
   756   - With mutual recursion, "bisim" predicate is now curried.
   757   - With mutual recursion, each type gets a separate coind theorem.
   758   - Variable names in bisim_def and coinduct rules have changed.
   759 
   760 INCOMPATIBILITY.
   761 
   762 * Case combinators generated by the domain package for type "foo" are
   763 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
   764 
   765 * Several theorems have been renamed to more accurately reflect the
   766 names of constants and types involved.  INCOMPATIBILITY.
   767 
   768   thelub_const    ~> lub_const
   769   lub_const       ~> is_lub_const
   770   thelubI         ~> lub_eqI
   771   is_lub_lub      ~> is_lubD2
   772   lubI            ~> is_lub_lub
   773   unique_lub      ~> is_lub_unique
   774   is_ub_lub       ~> is_lub_rangeD1
   775   lub_bin_chain   ~> is_lub_bin_chain
   776   lub_fun         ~> is_lub_fun
   777   thelub_fun      ~> lub_fun
   778   thelub_cfun     ~> lub_cfun
   779   thelub_Pair     ~> lub_Pair
   780   lub_cprod       ~> is_lub_prod
   781   thelub_cprod    ~> lub_prod
   782   minimal_cprod   ~> minimal_prod
   783   inst_cprod_pcpo ~> inst_prod_pcpo
   784   UU_I            ~> bottomI
   785   compact_UU      ~> compact_bottom
   786   deflation_UU    ~> deflation_bottom
   787   finite_deflation_UU ~> finite_deflation_bottom
   788 
   789 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
   790 
   791   sq_ord_less_eq_trans ~> below_eq_trans
   792   sq_ord_eq_less_trans ~> eq_below_trans
   793   refl_less            ~> below_refl
   794   trans_less           ~> below_trans
   795   antisym_less         ~> below_antisym
   796   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
   797   box_less             ~> box_below
   798   rev_trans_less       ~> rev_below_trans
   799   not_less2not_eq      ~> not_below2not_eq
   800   less_UU_iff          ~> below_UU_iff
   801   flat_less_iff        ~> flat_below_iff
   802   adm_less             ~> adm_below
   803   adm_not_less         ~> adm_not_below
   804   adm_compact_not_less ~> adm_compact_not_below
   805   less_fun_def         ~> below_fun_def
   806   expand_fun_less      ~> fun_below_iff
   807   less_fun_ext         ~> fun_belowI
   808   less_discr_def       ~> below_discr_def
   809   discr_less_eq        ~> discr_below_eq
   810   less_unit_def        ~> below_unit_def
   811   less_cprod_def       ~> below_prod_def
   812   prod_lessI           ~> prod_belowI
   813   Pair_less_iff        ~> Pair_below_iff
   814   fst_less_iff         ~> fst_below_iff
   815   snd_less_iff         ~> snd_below_iff
   816   expand_cfun_less     ~> cfun_below_iff
   817   less_cfun_ext        ~> cfun_belowI
   818   injection_less       ~> injection_below
   819   less_up_def          ~> below_up_def
   820   not_Iup_less         ~> not_Iup_below
   821   Iup_less             ~> Iup_below
   822   up_less              ~> up_below
   823   Def_inject_less_eq   ~> Def_below_Def
   824   Def_less_is_eq       ~> Def_below_iff
   825   spair_less_iff       ~> spair_below_iff
   826   less_sprod           ~> below_sprod
   827   spair_less           ~> spair_below
   828   sfst_less_iff        ~> sfst_below_iff
   829   ssnd_less_iff        ~> ssnd_below_iff
   830   fix_least_less       ~> fix_least_below
   831   dist_less_one        ~> dist_below_one
   832   less_ONE             ~> below_ONE
   833   ONE_less_iff         ~> ONE_below_iff
   834   less_sinlD           ~> below_sinlD
   835   less_sinrD           ~> below_sinrD
   836 
   837 
   838 *** FOL and ZF ***
   839 
   840 * All constant names are now qualified internally and use proper
   841 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
   842 
   843 
   844 *** ML ***
   845 
   846 * Antiquotation @{assert} inlines a function bool -> unit that raises
   847 Fail if the argument is false.  Due to inlining the source position of
   848 failed assertions is included in the error output.
   849 
   850 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
   851 text is in practice always evaluated with a stable theory checkpoint.
   852 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
   853 
   854 * Antiquotation @{theory A} refers to theory A from the ancestry of
   855 the current context, not any accidental theory loader state as before.
   856 Potential INCOMPATIBILITY, subtle change in semantics.
   857 
   858 * Syntax.pretty_priority (default 0) configures the required priority
   859 of pretty-printed output and thus affects insertion of parentheses.
   860 
   861 * Syntax.default_root (default "any") configures the inner syntax
   862 category (nonterminal symbol) for parsing of terms.
   863 
   864 * Former exception Library.UnequalLengths now coincides with
   865 ListPair.UnequalLengths.
   866 
   867 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
   868 main functionality is provided by structure Simplifier.
   869 
   870 * Renamed raw "explode" function to "raw_explode" to emphasize its
   871 meaning.  Note that internally to Isabelle, Symbol.explode is used in
   872 almost all situations.
   873 
   874 * Discontinued obsolete function sys_error and exception SYS_ERROR.
   875 See implementation manual for further details on exceptions in
   876 Isabelle/ML.
   877 
   878 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   879 meaning.
   880 
   881 * Renamed structure PureThy to Pure_Thy and moved most of its
   882 operations to structure Global_Theory, to emphasize that this is
   883 rarely-used global-only stuff.
   884 
   885 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
   886 instead (or tracing for high-volume output).
   887 
   888 * Configuration option show_question_marks only affects regular pretty
   889 printing of types and terms, not raw Term.string_of_vname.
   890 
   891 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
   892 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
   893 @{thms} for most purposes.
   894 
   895 * ML structure Unsynchronized is never opened, not even in Isar
   896 interaction mode as before.  Old Unsynchronized.set etc. have been
   897 discontinued -- use plain := instead.  This should be *rare* anyway,
   898 since modern tools always work via official context data, notably
   899 configuration options.
   900 
   901 * Parallel and asynchronous execution requires special care concerning
   902 interrupts.  Structure Exn provides some convenience functions that
   903 avoid working directly with raw Interrupt.  User code must not absorb
   904 interrupts -- intermediate handling (for cleanup etc.) needs to be
   905 followed by re-raising of the original exception.  Another common
   906 source of mistakes are "handle _" patterns, which make the meaning of
   907 the program subject to physical effects of the environment.
   908 
   909 
   910 
   911 New in Isabelle2009-2 (June 2010)
   912 ---------------------------------
   913 
   914 *** General ***
   915 
   916 * Authentic syntax for *all* logical entities (type classes, type
   917 constructors, term constants): provides simple and robust
   918 correspondence between formal entities and concrete syntax.  Within
   919 the parse tree / AST representations, "constants" are decorated by
   920 their category (class, type, const) and spelled out explicitly with
   921 their full internal name.
   922 
   923 Substantial INCOMPATIBILITY concerning low-level syntax declarations
   924 and translations (translation rules and translation functions in ML).
   925 Some hints on upgrading:
   926 
   927   - Many existing uses of 'syntax' and 'translations' can be replaced
   928     by more modern 'type_notation', 'notation' and 'abbreviation',
   929     which are independent of this issue.
   930 
   931   - 'translations' require markup within the AST; the term syntax
   932     provides the following special forms:
   933 
   934       CONST c   -- produces syntax version of constant c from context
   935       XCONST c  -- literally c, checked as constant from context
   936       c         -- literally c, if declared by 'syntax'
   937 
   938     Plain identifiers are treated as AST variables -- occasionally the
   939     system indicates accidental variables via the error "rhs contains
   940     extra variables".
   941 
   942     Type classes and type constructors are marked according to their
   943     concrete syntax.  Some old translations rules need to be written
   944     for the "type" category, using type constructor application
   945     instead of pseudo-term application of the default category
   946     "logic".
   947 
   948   - 'parse_translation' etc. in ML may use the following
   949     antiquotations:
   950 
   951       @{class_syntax c}   -- type class c within parse tree / AST
   952       @{term_syntax c}    -- type constructor c within parse tree / AST
   953       @{const_syntax c}   -- ML version of "CONST c" above
   954       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
   955 
   956   - Literal types within 'typed_print_translations', i.e. those *not*
   957     represented as pseudo-terms are represented verbatim.  Use @{class
   958     c} or @{type_name c} here instead of the above syntax
   959     antiquotations.
   960 
   961 Note that old non-authentic syntax was based on unqualified base
   962 names, so all of the above "constant" names would coincide.  Recall
   963 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
   964 diagnose syntax problems.
   965 
   966 * Type constructors admit general mixfix syntax, not just infix.
   967 
   968 * Concrete syntax may be attached to local entities without a proof
   969 body, too.  This works via regular mixfix annotations for 'fix',
   970 'def', 'obtain' etc. or via the explicit 'write' command, which is
   971 similar to the 'notation' command in theory specifications.
   972 
   973 * Discontinued unnamed infix syntax (legacy feature for many years) --
   974 need to specify constant name and syntax separately.  Internal ML
   975 datatype constructors have been renamed from InfixName to Infix etc.
   976 Minor INCOMPATIBILITY.
   977 
   978 * Schematic theorem statements need to be explicitly markup as such,
   979 via commands 'schematic_lemma', 'schematic_theorem',
   980 'schematic_corollary'.  Thus the relevance of the proof is made
   981 syntactically clear, which impacts performance in a parallel or
   982 asynchronous interactive environment.  Minor INCOMPATIBILITY.
   983 
   984 * Use of cumulative prems via "!" in some proof methods has been
   985 discontinued (old legacy feature).
   986 
   987 * References 'trace_simp' and 'debug_simp' have been replaced by
   988 configuration options stored in the context. Enabling tracing (the
   989 case of debugging is similar) in proofs works via
   990 
   991   using [[trace_simp = true]]
   992 
   993 Tracing is then active for all invocations of the simplifier in
   994 subsequent goal refinement steps. Tracing may also still be enabled or
   995 disabled via the ProofGeneral settings menu.
   996 
   997 * Separate commands 'hide_class', 'hide_type', 'hide_const',
   998 'hide_fact' replace the former 'hide' KIND command.  Minor
   999 INCOMPATIBILITY.
  1000 
  1001 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  1002 more efficient than combinations with -q1 or -q2.
  1003 
  1004 
  1005 *** Pure ***
  1006 
  1007 * Proofterms record type-class reasoning explicitly, using the
  1008 "unconstrain" operation internally.  This eliminates all sort
  1009 constraints from a theorem and proof, introducing explicit
  1010 OFCLASS-premises.  On the proof term level, this operation is
  1011 automatically applied at theorem boundaries, such that closed proofs
  1012 are always free of sort constraints.  INCOMPATIBILITY for tools that
  1013 inspect proof terms.
  1014 
  1015 * Local theory specifications may depend on extra type variables that
  1016 are not present in the result type -- arguments TYPE('a) :: 'a itself
  1017 are added internally.  For example:
  1018 
  1019   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  1020 
  1021 * Predicates of locales introduced by classes carry a mandatory
  1022 "class" prefix.  INCOMPATIBILITY.
  1023 
  1024 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  1025 
  1026 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  1027 'class' instead.
  1028 
  1029 * Command 'code_reflect' allows to incorporate generated ML code into
  1030 runtime environment; replaces immature code_datatype antiquotation.
  1031 INCOMPATIBILITY.
  1032 
  1033 * Code generator: simple concept for abstract datatypes obeying
  1034 invariants.
  1035 
  1036 * Code generator: details of internal data cache have no impact on the
  1037 user space functionality any longer.
  1038 
  1039 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1040 subgoals.  This is more appropriate for interpretations with 'where'.
  1041 INCOMPATIBILITY.
  1042 
  1043 * Command 'example_proof' opens an empty proof body.  This allows to
  1044 experiment with Isar, without producing any persistent result.
  1045 
  1046 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1047 within a local theory context, with explicit checking of the
  1048 constructors involved (in contrast to the raw 'syntax' versions).
  1049 
  1050 * Commands 'types' and 'typedecl' now work within a local theory
  1051 context -- without introducing dependencies on parameters or
  1052 assumptions, which is not possible in Isabelle/Pure.
  1053 
  1054 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1055 within a local theory context.  Minor INCOMPATIBILITY.
  1056 
  1057 
  1058 *** HOL ***
  1059 
  1060 * Command 'typedef' now works within a local theory context -- without
  1061 introducing dependencies on parameters or assumptions, which is not
  1062 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1063 contain multiple interpretations of local typedefs (with different
  1064 non-emptiness proofs), even in a global theory context.
  1065 
  1066 * New package for quotient types.  Commands 'quotient_type' and
  1067 'quotient_definition' may be used for defining types and constants by
  1068 quotient constructions.  An example is the type of integers created by
  1069 quotienting pairs of natural numbers:
  1070 
  1071   fun
  1072     intrel :: "(nat * nat) => (nat * nat) => bool"
  1073   where
  1074     "intrel (x, y) (u, v) = (x + v = u + y)"
  1075 
  1076   quotient_type int = "nat * nat" / intrel
  1077     by (auto simp add: equivp_def expand_fun_eq)
  1078 
  1079   quotient_definition
  1080     "0::int" is "(0::nat, 0::nat)"
  1081 
  1082 The method "lifting" can be used to lift of theorems from the
  1083 underlying "raw" type to the quotient type.  The example
  1084 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1085 construction and provides a reasoning infrastructure for finite sets.
  1086 
  1087 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1088 clash with new theory Quotient in Main HOL.
  1089 
  1090 * Moved the SMT binding into the main HOL session, eliminating
  1091 separate HOL-SMT session.
  1092 
  1093 * List membership infix mem operation is only an input abbreviation.
  1094 INCOMPATIBILITY.
  1095 
  1096 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1097 for future developements; former Library/Word.thy is still present in
  1098 the AFP entry RSAPPS.
  1099 
  1100 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1101 longer shadowed.  INCOMPATIBILITY.
  1102 
  1103 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1104 INCOMPATIBILITY.
  1105 
  1106 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1107 INCOMPATIBILITY.
  1108 
  1109 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1110 instead.  INCOMPATIBILITY.
  1111 
  1112 * Dropped several real-specific versions of lemmas about floor and
  1113 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1114 instead.  INCOMPATIBILITY.
  1115 
  1116   floor_number_of_eq         ~> floor_number_of
  1117   le_floor_eq_number_of      ~> number_of_le_floor
  1118   le_floor_eq_zero           ~> zero_le_floor
  1119   le_floor_eq_one            ~> one_le_floor
  1120   floor_less_eq_number_of    ~> floor_less_number_of
  1121   floor_less_eq_zero         ~> floor_less_zero
  1122   floor_less_eq_one          ~> floor_less_one
  1123   less_floor_eq_number_of    ~> number_of_less_floor
  1124   less_floor_eq_zero         ~> zero_less_floor
  1125   less_floor_eq_one          ~> one_less_floor
  1126   floor_le_eq_number_of      ~> floor_le_number_of
  1127   floor_le_eq_zero           ~> floor_le_zero
  1128   floor_le_eq_one            ~> floor_le_one
  1129   floor_subtract_number_of   ~> floor_diff_number_of
  1130   floor_subtract_one         ~> floor_diff_one
  1131   ceiling_number_of_eq       ~> ceiling_number_of
  1132   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1133   ceiling_le_zero_eq         ~> ceiling_le_zero
  1134   ceiling_le_eq_one          ~> ceiling_le_one
  1135   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1136   less_ceiling_eq_zero       ~> zero_less_ceiling
  1137   less_ceiling_eq_one        ~> one_less_ceiling
  1138   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1139   ceiling_less_eq_zero       ~> ceiling_less_zero
  1140   ceiling_less_eq_one        ~> ceiling_less_one
  1141   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1142   le_ceiling_eq_zero         ~> zero_le_ceiling
  1143   le_ceiling_eq_one          ~> one_le_ceiling
  1144   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1145   ceiling_subtract_one       ~> ceiling_diff_one
  1146 
  1147 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1148 application of the various fold combinators on finite sets.
  1149 
  1150 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1151 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1152 implementation.  INCOMPATIBILTY.
  1153 
  1154 * Theory Library/Coinductive_List has been removed -- superseded by
  1155 AFP/thys/Coinductive.
  1156 
  1157 * Theory PReal, including the type "preal" and related operations, has
  1158 been removed.  INCOMPATIBILITY.
  1159 
  1160 * Real: new development using Cauchy Sequences.
  1161 
  1162 * Split off theory "Big_Operators" containing setsum, setprod,
  1163 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1164 
  1165 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1166 "Int" etc.  INCOMPATIBILITY.
  1167 
  1168 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1169 
  1170 * New set of rules "ac_simps" provides combined assoc / commute
  1171 rewrites for all interpretations of the appropriate generic locales.
  1172 
  1173 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1174 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1175 appropriate and more consistent names suitable for name prefixes
  1176 within the HOL theories.  INCOMPATIBILITY.
  1177 
  1178 * Some generic constants have been put to appropriate theories:
  1179   - less_eq, less: Orderings
  1180   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1181   - inverse, divide: Rings
  1182 INCOMPATIBILITY.
  1183 
  1184 * More consistent naming of type classes involving orderings (and
  1185 lattices):
  1186 
  1187     lower_semilattice                   ~> semilattice_inf
  1188     upper_semilattice                   ~> semilattice_sup
  1189 
  1190     dense_linear_order                  ~> dense_linorder
  1191 
  1192     pordered_ab_group_add               ~> ordered_ab_group_add
  1193     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1194     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1195     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1196     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1197     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1198     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1199     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1200     pordered_comm_ring                  ~> ordered_comm_ring
  1201     pordered_comm_semiring              ~> ordered_comm_semiring
  1202     pordered_ring                       ~> ordered_ring
  1203     pordered_ring_abs                   ~> ordered_ring_abs
  1204     pordered_semiring                   ~> ordered_semiring
  1205 
  1206     ordered_ab_group_add                ~> linordered_ab_group_add
  1207     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1208     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1209     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1210     ordered_field                       ~> linordered_field
  1211     ordered_field_no_lb                 ~> linordered_field_no_lb
  1212     ordered_field_no_ub                 ~> linordered_field_no_ub
  1213     ordered_field_dense_linear_order    ~> dense_linordered_field
  1214     ordered_idom                        ~> linordered_idom
  1215     ordered_ring                        ~> linordered_ring
  1216     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1217     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1218     ordered_ring_strict                 ~> linordered_ring_strict
  1219     ordered_semidom                     ~> linordered_semidom
  1220     ordered_semiring                    ~> linordered_semiring
  1221     ordered_semiring_1                  ~> linordered_semiring_1
  1222     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1223     ordered_semiring_strict             ~> linordered_semiring_strict
  1224 
  1225   The following slightly odd type classes have been moved to a
  1226   separate theory Library/Lattice_Algebras:
  1227 
  1228     lordered_ab_group_add               ~> lattice_ab_group_add
  1229     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1230     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1231     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1232     lordered_ring                       ~> lattice_ring
  1233 
  1234 INCOMPATIBILITY.
  1235 
  1236 * Refined field classes:
  1237   - classes division_ring_inverse_zero, field_inverse_zero,
  1238     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1239     subsumes former division_by_zero class;
  1240   - numerous lemmas have been ported from field to division_ring.
  1241 INCOMPATIBILITY.
  1242 
  1243 * Refined algebra theorem collections:
  1244   - dropped theorem group group_simps, use algebra_simps instead;
  1245   - dropped theorem group ring_simps, use field_simps instead;
  1246   - proper theorem collection field_simps subsumes former theorem
  1247     groups field_eq_simps and field_simps;
  1248   - dropped lemma eq_minus_self_iff which is a duplicate for
  1249     equal_neg_zero.
  1250 INCOMPATIBILITY.
  1251 
  1252 * Theory Finite_Set and List: some lemmas have been generalized from
  1253 sets to lattices:
  1254 
  1255   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1256   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1257   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1258   union_Union_fold_union        ~> sup_Sup_fold_sup
  1259   Inter_fold_inter              ~> Inf_fold_inf
  1260   Union_fold_union              ~> Sup_fold_sup
  1261   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1262   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1263   INTER_fold_inter              ~> INFI_fold_inf
  1264   UNION_fold_union              ~> SUPR_fold_sup
  1265 
  1266 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1267 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1268 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1269 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1270 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1271 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1272 
  1273 * Reorganized theory Multiset: swapped notation of pointwise and
  1274 multiset order:
  1275 
  1276   - pointwise ordering is instance of class order with standard syntax
  1277     <= and <;
  1278   - multiset ordering has syntax <=# and <#; partial order properties
  1279     are provided by means of interpretation with prefix
  1280     multiset_order;
  1281   - less duplication, less historical organization of sections,
  1282     conversion from associations lists to multisets, rudimentary code
  1283     generation;
  1284   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1285     if needed.
  1286 
  1287 Renamed:
  1288 
  1289   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1290   multi_count_ext  ~>  multiset_ext
  1291   diff_union_inverse2  ~>  diff_union_cancelR
  1292 
  1293 INCOMPATIBILITY.
  1294 
  1295 * Theory Permutation: replaced local "remove" by List.remove1.
  1296 
  1297 * Code generation: ML and OCaml code is decorated with signatures.
  1298 
  1299 * Theory List: added transpose.
  1300 
  1301 * Library/Nat_Bijection.thy is a collection of bijective functions
  1302 between nat and other types, which supersedes the older libraries
  1303 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1304 
  1305   Constants:
  1306   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1307   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1308   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1309   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1310   Countable.pair_encode           ~> prod_encode
  1311   NatIso.prod2nat                 ~> prod_encode
  1312   NatIso.nat2prod                 ~> prod_decode
  1313   NatIso.sum2nat                  ~> sum_encode
  1314   NatIso.nat2sum                  ~> sum_decode
  1315   NatIso.list2nat                 ~> list_encode
  1316   NatIso.nat2list                 ~> list_decode
  1317   NatIso.set2nat                  ~> set_encode
  1318   NatIso.nat2set                  ~> set_decode
  1319 
  1320   Lemmas:
  1321   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1322   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1323   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1324   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1325   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1326   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1327   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1328   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1329   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1330   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1331   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1332   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1333   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1334 
  1335 * Sledgehammer:
  1336   - Renamed ATP commands:
  1337     atp_info     ~> sledgehammer running_atps
  1338     atp_kill     ~> sledgehammer kill_atps
  1339     atp_messages ~> sledgehammer messages
  1340     atp_minimize ~> sledgehammer minimize
  1341     print_atps   ~> sledgehammer available_atps
  1342     INCOMPATIBILITY.
  1343   - Added user's manual ("isabelle doc sledgehammer").
  1344   - Added option syntax and "sledgehammer_params" to customize
  1345     Sledgehammer's behavior.  See the manual for details.
  1346   - Modified the Isar proof reconstruction code so that it produces
  1347     direct proofs rather than proofs by contradiction.  (This feature
  1348     is still experimental.)
  1349   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1350     full-typed mode.
  1351   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1352 
  1353 * Nitpick:
  1354   - Added and implemented "binary_ints" and "bits" options.
  1355   - Added "std" option and implemented support for nonstandard models.
  1356   - Added and implemented "finitize" option to improve the precision
  1357     of infinite datatypes based on a monotonicity analysis.
  1358   - Added support for quotient types.
  1359   - Added support for "specification" and "ax_specification"
  1360     constructs.
  1361   - Added support for local definitions (for "function" and
  1362     "termination" proofs).
  1363   - Added support for term postprocessors.
  1364   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1365   - Improved efficiency of "destroy_constrs" optimization.
  1366   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1367     record getters.
  1368   - Fixed soundness bug related to higher-order constructors.
  1369   - Fixed soundness bug when "full_descrs" is enabled.
  1370   - Improved precision of set constructs.
  1371   - Added "atoms" option.
  1372   - Added cache to speed up repeated Kodkod invocations on the same
  1373     problems.
  1374   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1375     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1376     "SAT4J_Light".  INCOMPATIBILITY.
  1377   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1378     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1379   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1380 
  1381 * Method "induct" now takes instantiations of the form t, where t is not
  1382   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1383   If this is not intended, t has to be enclosed in parentheses.
  1384   By default, the equalities generated by definitional instantiations
  1385   are pre-simplified, which may cause parameters of inductive cases
  1386   to disappear, or may even delete some of the inductive cases.
  1387   Use "induct (no_simp)" instead of "induct" to restore the old
  1388   behaviour. The (no_simp) option is also understood by the "cases"
  1389   and "nominal_induct" methods, which now perform pre-simplification, too.
  1390   INCOMPATIBILITY.
  1391 
  1392 
  1393 *** HOLCF ***
  1394 
  1395 * Variable names in lemmas generated by the domain package have
  1396 changed; the naming scheme is now consistent with the HOL datatype
  1397 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1398 
  1399 * The domain package no longer defines the function "foo_copy" for
  1400 recursive domain "foo".  The reach lemma is now stated directly in
  1401 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1402 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1403 
  1404 * Most definedness lemmas generated by the domain package (previously
  1405 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1406 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1407 Proofs that used definedness lemmas as intro rules may break,
  1408 potential INCOMPATIBILITY.
  1409 
  1410 * Induction and casedist rules generated by the domain package now
  1411 declare proper case_names (one called "bottom", and one named for each
  1412 constructor).  INCOMPATIBILITY.
  1413 
  1414 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1415 rules are generated for each domain, INCOMPATIBILITY.
  1416 
  1417   foo_bar.reach       ~> foo.reach  bar.reach
  1418   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1419 
  1420 * Some lemmas generated by the domain package have been renamed for
  1421 consistency with the datatype package, INCOMPATIBILITY.
  1422 
  1423   foo.ind        ~> foo.induct
  1424   foo.finite_ind ~> foo.finite_induct
  1425   foo.coind      ~> foo.coinduct
  1426   foo.casedist   ~> foo.exhaust
  1427   foo.exhaust    ~> foo.nchotomy
  1428 
  1429 * For consistency with other definition packages, the fixrec package
  1430 now generates qualified theorem names, INCOMPATIBILITY.
  1431 
  1432   foo_simps  ~> foo.simps
  1433   foo_unfold ~> foo.unfold
  1434   foo_induct ~> foo.induct
  1435 
  1436 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1437 method and internal fixrec proofs now use the default simpset instead.
  1438 INCOMPATIBILITY.
  1439 
  1440 * The "contlub" predicate has been removed.  Proof scripts should use
  1441 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1442 
  1443 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1444 
  1445 * The constants cpair, cfst, and csnd have been removed in favor of
  1446 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1447 
  1448 
  1449 *** ML ***
  1450 
  1451 * Antiquotations for basic formal entities:
  1452 
  1453     @{class NAME}         -- type class
  1454     @{class_syntax NAME}  -- syntax representation of the above
  1455 
  1456     @{type_name NAME}     -- logical type
  1457     @{type_abbrev NAME}   -- type abbreviation
  1458     @{nonterminal NAME}   -- type of concrete syntactic category
  1459     @{type_syntax NAME}   -- syntax representation of any of the above
  1460 
  1461     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1462     @{const_abbrev NAME}  -- abbreviated constant
  1463     @{const_syntax NAME}  -- syntax representation of any of the above
  1464 
  1465 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1466 syntax constant (cf. 'syntax' command).
  1467 
  1468 * Antiquotation @{make_string} inlines a function to print arbitrary
  1469 values similar to the ML toplevel.  The result is compiler dependent
  1470 and may fall back on "?" in certain situations.
  1471 
  1472 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1473 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1474 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1475 not work with the asynchronous Isar document model.
  1476 
  1477 * Configuration options now admit dynamic default values, depending on
  1478 the context or even global references.
  1479 
  1480 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1481 uses an efficient external library if available (for Poly/ML).
  1482 
  1483 * Renamed some important ML structures, while keeping the old names
  1484 for some time as aliases within the structure Legacy:
  1485 
  1486   OuterKeyword  ~>  Keyword
  1487   OuterLex      ~>  Token
  1488   OuterParse    ~>  Parse
  1489   OuterSyntax   ~>  Outer_Syntax
  1490   PrintMode     ~>  Print_Mode
  1491   SpecParse     ~>  Parse_Spec
  1492   ThyInfo       ~>  Thy_Info
  1493   ThyLoad       ~>  Thy_Load
  1494   ThyOutput     ~>  Thy_Output
  1495   TypeInfer     ~>  Type_Infer
  1496 
  1497 Note that "open Legacy" simplifies porting of sources, but forgetting
  1498 to remove it again will complicate porting again in the future.
  1499 
  1500 * Most operations that refer to a global context are named
  1501 accordingly, e.g. Simplifier.global_context or
  1502 ProofContext.init_global.  There are some situations where a global
  1503 context actually works, but under normal circumstances one needs to
  1504 pass the proper local context through the code!
  1505 
  1506 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1507 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1508 Pretty.pp argument to merge, which is absent in the standard
  1509 Theory_Data version.
  1510 
  1511 * Sorts.certify_sort and derived "cert" operations for types and terms
  1512 no longer minimize sorts.  Thus certification at the boundary of the
  1513 inference kernel becomes invariant under addition of class relations,
  1514 which is an important monotonicity principle.  Sorts are now minimized
  1515 in the syntax layer only, at the boundary between the end-user and the
  1516 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1517 explicitly in rare situations.
  1518 
  1519 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1520 emphasize that this is in no way a standard operation.
  1521 INCOMPATIBILITY.
  1522 
  1523 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1524 usual for resolution.  Rare INCOMPATIBILITY.
  1525 
  1526 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1527 to emphasize that these only work in a global situation (which is
  1528 quite rare).
  1529 
  1530 * Curried take and drop in library.ML; negative length is interpreted
  1531 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1532 
  1533 * Proof terms: type substitutions on proof constants now use canonical
  1534 order of type variables.  INCOMPATIBILITY for tools working with proof
  1535 terms.
  1536 
  1537 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1538 may no longer carry premises.  User-level specifications are
  1539 transformed accordingly by Thm.add_axiom/add_def.
  1540 
  1541 
  1542 *** System ***
  1543 
  1544 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1545 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1546 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1547 
  1548 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1549 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1550 respectively.
  1551 
  1552 * Old lib/scripts/polyml-platform is superseded by the
  1553 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1554 variant, even on a 64 bit machine.  The following example setting
  1555 prefers 64 bit if available:
  1556 
  1557   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1558 
  1559 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1560 Isabelle/Scala layer for advanced prover interaction and integration.
  1561 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1562 component.
  1563 
  1564 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1565 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1566 similar to the default assignment of the document preparation system
  1567 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1568 provides some operations for direct access to the font without asking
  1569 the user for manual installation.
  1570 
  1571 
  1572 
  1573 New in Isabelle2009-1 (December 2009)
  1574 -------------------------------------
  1575 
  1576 *** General ***
  1577 
  1578 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1579 one backslash should be used, even in ML sources.
  1580 
  1581 
  1582 *** Pure ***
  1583 
  1584 * Locale interpretation propagates mixins along the locale hierarchy.
  1585 The currently only available mixins are the equations used to map
  1586 local definitions to terms of the target domain of an interpretation.
  1587 
  1588 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1589 loc" to print all interpretations of locale "loc" in the theory.
  1590 Interpretations in proofs are not shown.
  1591 
  1592 * Thoroughly revised locales tutorial.  New section on conditional
  1593 interpretation.
  1594 
  1595 * On instantiation of classes, remaining undefined class parameters
  1596 are formally declared.  INCOMPATIBILITY.
  1597 
  1598 
  1599 *** Document preparation ***
  1600 
  1601 * New generalized style concept for printing terms: @{foo (style) ...}
  1602 instead of @{foo_style style ...}  (old form is still retained for
  1603 backward compatibility).  Styles can be also applied for
  1604 antiquotations prop, term_type and typeof.
  1605 
  1606 
  1607 *** HOL ***
  1608 
  1609 * New proof method "smt" for a combination of first-order logic with
  1610 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1611 fixed-size bitvectors; there is also basic support for higher-order
  1612 features (esp. lambda abstractions).  It is an incomplete decision
  1613 procedure based on external SMT solvers using the oracle mechanism;
  1614 for the SMT solver Z3, this method is proof-producing.  Certificates
  1615 are provided to avoid calling the external solvers solely for
  1616 re-checking proofs.  Due to a remote SMT service there is no need for
  1617 installing SMT solvers locally.  See src/HOL/SMT.
  1618 
  1619 * New commands to load and prove verification conditions generated by
  1620 the Boogie program verifier or derived systems (e.g. the Verifying C
  1621 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1622 
  1623 * New counterexample generator tool 'nitpick' based on the Kodkod
  1624 relational model finder.  See src/HOL/Tools/Nitpick and
  1625 src/HOL/Nitpick_Examples.
  1626 
  1627 * New commands 'code_pred' and 'values' to invoke the predicate
  1628 compiler and to enumerate values of inductive predicates.
  1629 
  1630 * A tabled implementation of the reflexive transitive closure.
  1631 
  1632 * New implementation of quickcheck uses generic code generator;
  1633 default generators are provided for all suitable HOL types, records
  1634 and datatypes.  Old quickcheck can be re-activated importing theory
  1635 Library/SML_Quickcheck.
  1636 
  1637 * New testing tool Mirabelle for automated proof tools.  Applies
  1638 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1639 every proof step in a theory.  To be used in batch mode via the
  1640 "mirabelle" utility.
  1641 
  1642 * New proof method "sos" (sum of squares) for nonlinear real
  1643 arithmetic (originally due to John Harison). It requires theory
  1644 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1645 works well in practice on quantifier-free real arithmetic with +, -,
  1646 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1647 inequalities between polynomials.  It makes use of external
  1648 semidefinite programming solvers.  Method "sos" generates a
  1649 certificate that can be pasted into the proof thus avoiding the need
  1650 to call an external tool every time the proof is checked.  See
  1651 src/HOL/Library/Sum_Of_Squares.
  1652 
  1653 * New method "linarith" invokes existing linear arithmetic decision
  1654 procedure only.
  1655 
  1656 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1657 
  1658 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1659 Causes full type information to be output to the ATPs.  This slows
  1660 ATPs down considerably but eliminates a source of unsound "proofs"
  1661 that fail later.
  1662 
  1663 * New method "metisFT": A version of metis that uses full type
  1664 information in order to avoid failures of proof reconstruction.
  1665 
  1666 * New evaluator "approximate" approximates an real valued term using
  1667 the same method as the approximation method.
  1668 
  1669 * Method "approximate" now supports arithmetic expressions as
  1670 boundaries of intervals and implements interval splitting and Taylor
  1671 series expansion.
  1672 
  1673 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1674 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1675 
  1676 * New theory SupInf of the supremum and infimum operators for sets of
  1677 reals.
  1678 
  1679 * New theory Probability, which contains a development of measure
  1680 theory, eventually leading to Lebesgue integration and probability.
  1681 
  1682 * Extended Multivariate Analysis to include derivation and Brouwer's
  1683 fixpoint theorem.
  1684 
  1685 * Reorganization of number theory, INCOMPATIBILITY:
  1686   - new number theory development for nat and int, in theories Divides
  1687     and GCD as well as in new session Number_Theory
  1688   - some constants and facts now suffixed with _nat and _int
  1689     accordingly
  1690   - former session NumberTheory now named Old_Number_Theory, including
  1691     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1692   - moved theory Pocklington from src/HOL/Library to
  1693     src/HOL/Old_Number_Theory
  1694 
  1695 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1696 lcm of finite and infinite sets. It is shown that they form a complete
  1697 lattice.
  1698 
  1699 * Class semiring_div requires superclass no_zero_divisors and proof of
  1700 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1701 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1702 generalized to class semiring_div, subsuming former theorems
  1703 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1704 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1705 INCOMPATIBILITY.
  1706 
  1707 * Refinements to lattice classes and sets:
  1708   - less default intro/elim rules in locale variant, more default
  1709     intro/elim rules in class variant: more uniformity
  1710   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1711     le_inf_iff
  1712   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1713     sup_aci)
  1714   - renamed ACI to inf_sup_aci
  1715   - new class "boolean_algebra"
  1716   - class "complete_lattice" moved to separate theory
  1717     "Complete_Lattice"; corresponding constants (and abbreviations)
  1718     renamed and with authentic syntax:
  1719     Set.Inf ~>    Complete_Lattice.Inf
  1720     Set.Sup ~>    Complete_Lattice.Sup
  1721     Set.INFI ~>   Complete_Lattice.INFI
  1722     Set.SUPR ~>   Complete_Lattice.SUPR
  1723     Set.Inter ~>  Complete_Lattice.Inter
  1724     Set.Union ~>  Complete_Lattice.Union
  1725     Set.INTER ~>  Complete_Lattice.INTER
  1726     Set.UNION ~>  Complete_Lattice.UNION
  1727   - authentic syntax for
  1728     Set.Pow
  1729     Set.image
  1730   - mere abbreviations:
  1731     Set.empty               (for bot)
  1732     Set.UNIV                (for top)
  1733     Set.inter               (for inf, formerly Set.Int)
  1734     Set.union               (for sup, formerly Set.Un)
  1735     Complete_Lattice.Inter  (for Inf)
  1736     Complete_Lattice.Union  (for Sup)
  1737     Complete_Lattice.INTER  (for INFI)
  1738     Complete_Lattice.UNION  (for SUPR)
  1739   - object-logic definitions as far as appropriate
  1740 
  1741 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1742 Un_subset_iff are explicitly deleted as default simp rules; then also
  1743 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1744 deleted to achieve the desired effect.
  1745 
  1746 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1747 rules by default any longer; the same applies to min_max.inf_absorb1
  1748 etc.  INCOMPATIBILITY.
  1749 
  1750 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1751 pred_set_conv by default.  INCOMPATIBILITY.
  1752 
  1753 * Power operations on relations and functions are now one dedicated
  1754 constant "compow" with infix syntax "^^".  Power operation on
  1755 multiplicative monoids retains syntax "^" and is now defined generic
  1756 in class power.  INCOMPATIBILITY.
  1757 
  1758 * Relation composition "R O S" now has a more standard argument order:
  1759 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1760 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1761 break, since the O_assoc rule was not rewritten like this.  Fix using
  1762 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1763 
  1764 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1765 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1766 INCOMPATIBILITY.
  1767 
  1768 * Most rules produced by inductive and datatype package have mandatory
  1769 prefixes.  INCOMPATIBILITY.
  1770 
  1771 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1772 the attribute of the same name.  Each of the theorems in the list
  1773 DERIV_intros assumes composition with an additional function and
  1774 matches a variable to the derivative, which has to be solved by the
  1775 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1776 of most elementary terms.  Former Maclauren.DERIV_tac and
  1777 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1778 INCOMPATIBILITY.
  1779 
  1780 * Code generator attributes follow the usual underscore convention:
  1781     code_unfold     replaces    code unfold
  1782     code_post       replaces    code post
  1783     etc.
  1784   INCOMPATIBILITY.
  1785 
  1786 * Renamed methods:
  1787     sizechange -> size_change
  1788     induct_scheme -> induction_schema
  1789   INCOMPATIBILITY.
  1790 
  1791 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1792 INCOMPATIBILITY, use "undefined" directly.
  1793 
  1794 * Renamed theorems:
  1795     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1796     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1797     Suc_plus1 -> Suc_eq_plus1
  1798     *anti_sym -> *antisym*
  1799     vector_less_eq_def -> vector_le_def
  1800   INCOMPATIBILITY.
  1801 
  1802 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1803 INCOMPATIBILITY.
  1804 
  1805 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1806 INCOMPATIBILITY.
  1807 
  1808 
  1809 *** HOLCF ***
  1810 
  1811 * Theory Representable defines a class "rep" of domains that are
  1812 representable (via an ep-pair) in the universal domain type "udom".
  1813 Instances are provided for all type constructors defined in HOLCF.
  1814 
  1815 * The 'new_domain' command is a purely definitional version of the
  1816 domain package, for representable domains.  Syntax is identical to the
  1817 old domain package.  The 'new_domain' package also supports indirect
  1818 recursion using previously-defined type constructors.  See
  1819 src/HOLCF/ex/New_Domain.thy for examples.
  1820 
  1821 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1822 on the left-hand side of an equation, and then performs
  1823 simplification.  Rewriting is done using rules declared with the
  1824 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1825 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1826 
  1827 * The pattern-match compiler in 'fixrec' can now handle constructors
  1828 with HOL function types.  Pattern-match combinators for the Pair
  1829 constructor are pre-configured.
  1830 
  1831 * The 'fixrec' package now produces better fixed-point induction rules
  1832 for mutually-recursive definitions:  Induction rules have conclusions
  1833 of the form "P foo bar" instead of "P <foo, bar>".
  1834 
  1835 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1836 been renamed to "below".  The name "below" now replaces "less" in many
  1837 theorem names.  (Legacy theorem names using "less" are still supported
  1838 as well.)
  1839 
  1840 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1841 patterns can be used to generate strictness rules, or to make
  1842 functions more strict (much like the bang-patterns supported by the
  1843 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1844 examples.
  1845 
  1846 
  1847 *** ML ***
  1848 
  1849 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1850 errors and run-time exceptions, including detailed source positions.
  1851 
  1852 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1853 identified entries, with some additional information such as source
  1854 position, logical grouping etc.
  1855 
  1856 * Theory and context data is now introduced by the simplified and
  1857 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1858 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1859 copy operation) is still available for some time.
  1860 
  1861 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1862 provides a high-level programming interface to synchronized state
  1863 variables with atomic update.  This works via pure function
  1864 application within a critical section -- its runtime should be as
  1865 short as possible; beware of deadlocks if critical code is nested,
  1866 either directly or indirectly via other synchronized variables!
  1867 
  1868 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1869 wraps raw ML references, explicitly indicating their non-thread-safe
  1870 behaviour.  The Isar toplevel keeps this structure open, to
  1871 accommodate Proof General as well as quick and dirty interactive
  1872 experiments with references.
  1873 
  1874 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1875 parallel tactical reasoning.
  1876 
  1877 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1878 are similar to SUBPROOF, but are slightly more flexible: only the
  1879 specified parts of the subgoal are imported into the context, and the
  1880 body tactic may introduce new subgoals and schematic variables.
  1881 
  1882 * Old tactical METAHYPS, which does not observe the proof context, has
  1883 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1884 or Subgoal.FOCUS etc.
  1885 
  1886 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1887 functors have their own ML name space there is no point to mark them
  1888 separately.)  Minor INCOMPATIBILITY.
  1889 
  1890 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1891 
  1892 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1893 INCOMPATIBILITY.
  1894 
  1895 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1896 mode, which avoids critical setmp.
  1897 
  1898 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1899 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1900 Attrib/Method.setup introduced in Isabelle2009.
  1901 
  1902 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1903 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1904 last resort.  INCOMPATIBILITY.
  1905 
  1906 * Display.pretty_thm now requires a proper context (cf. former
  1907 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1908 or even Display.pretty_thm_without_context as last resort.
  1909 INCOMPATIBILITY.
  1910 
  1911 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1912 Syntax.pretty_typ/term directly, preferably with proper context
  1913 instead of global theory.
  1914 
  1915 
  1916 *** System ***
  1917 
  1918 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1919 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1920 usedir option -q.
  1921 
  1922 * Support for additional "Isabelle components" via etc/components, see
  1923 also the system manual.
  1924 
  1925 * The isabelle makeall tool now operates on all components with
  1926 IsaMakefile, not just hardwired "logics".
  1927 
  1928 * Removed "compress" option from isabelle-process and isabelle usedir;
  1929 this is always enabled.
  1930 
  1931 * Discontinued support for Poly/ML 4.x versions.
  1932 
  1933 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  1934 on a given logic image.  This requires the lighttpd webserver and is
  1935 currently supported on Linux only.
  1936 
  1937 
  1938 
  1939 New in Isabelle2009 (April 2009)
  1940 --------------------------------
  1941 
  1942 *** General ***
  1943 
  1944 * Simplified main Isabelle executables, with less surprises on
  1945 case-insensitive file-systems (such as Mac OS).
  1946 
  1947   - The main Isabelle tool wrapper is now called "isabelle" instead of
  1948     "isatool."
  1949 
  1950   - The former "isabelle" alias for "isabelle-process" has been
  1951     removed (should rarely occur to regular users).
  1952 
  1953   - The former "isabelle-interface" and its alias "Isabelle" have been
  1954     removed (interfaces are now regular Isabelle tools).
  1955 
  1956 Within scripts and make files, the Isabelle environment variables
  1957 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  1958 respectively.  (The latter are still available as legacy feature.)
  1959 
  1960 The old isabelle-interface wrapper could react in confusing ways if
  1961 the interface was uninstalled or changed otherwise.  Individual
  1962 interface tool configuration is now more explicit, see also the
  1963 Isabelle system manual.  In particular, Proof General is now available
  1964 via "isabelle emacs".
  1965 
  1966 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  1967 purge installed copies of Isabelle executables and re-run "isabelle
  1968 install -p ...", or use symlinks.
  1969 
  1970 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  1971 old ~/isabelle, which was slightly non-standard and apt to cause
  1972 surprises on case-insensitive file-systems (such as Mac OS).
  1973 
  1974 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  1975 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  1976 care is required when using older releases of Isabelle.  Note that
  1977 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  1978 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  1979 
  1980 * Proofs of fully specified statements are run in parallel on
  1981 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  1982 a regular 4-core machine, if the initial heap space is made reasonably
  1983 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  1984 
  1985 * The main reference manuals ("isar-ref", "implementation", and
  1986 "system") have been updated and extended.  Formally checked references
  1987 as hyperlinks are now available uniformly.
  1988 
  1989 
  1990 *** Pure ***
  1991 
  1992 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  1993 respects.  The most important changes are listed below.  See the
  1994 Tutorial on Locales ("locales" manual) for details.
  1995 
  1996 - In locale expressions, instantiation replaces renaming.  Parameters
  1997 must be declared in a for clause.  To aid compatibility with previous
  1998 parameter inheritance, in locale declarations, parameters that are not
  1999 'touched' (instantiation position "_" or omitted) are implicitly added
  2000 with their syntax at the beginning of the for clause.
  2001 
  2002 - Syntax from abbreviations and definitions in locales is available in
  2003 locale expressions and context elements.  The latter is particularly
  2004 useful in locale declarations.
  2005 
  2006 - More flexible mechanisms to qualify names generated by locale
  2007 expressions.  Qualifiers (prefixes) may be specified in locale
  2008 expressions, and can be marked as mandatory (syntax: "name!:") or
  2009 optional (syntax "name?:").  The default depends for plain "name:"
  2010 depends on the situation where a locale expression is used: in
  2011 commands 'locale' and 'sublocale' prefixes are optional, in
  2012 'interpretation' and 'interpret' prefixes are mandatory.  The old
  2013 implicit qualifiers derived from the parameter names of a locale are
  2014 no longer generated.
  2015 
  2016 - Command "sublocale l < e" replaces "interpretation l < e".  The
  2017 instantiation clause in "interpretation" and "interpret" (square
  2018 brackets) is no longer available.  Use locale expressions.
  2019 
  2020 - When converting proof scripts, mandatory qualifiers in
  2021 'interpretation' and 'interpret' should be retained by default, even
  2022 if this is an INCOMPATIBILITY compared to former behavior.  In the
  2023 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  2024 in locale expressions range over a single locale instance only.
  2025 
  2026 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  2027 In existing theorem specifications replace the includes element by the
  2028 respective context elements of the included locale, omitting those
  2029 that are already present in the theorem specification.  Multiple
  2030 assume elements of a locale should be replaced by a single one
  2031 involving the locale predicate.  In the proof body, declarations (most
  2032 notably theorems) may be regained by interpreting the respective
  2033 locales in the proof context as required (command "interpret").
  2034 
  2035 If using "includes" in replacement of a target solely because the
  2036 parameter types in the theorem are not as general as in the target,
  2037 consider declaring a new locale with additional type constraints on
  2038 the parameters (context element "constrains").
  2039 
  2040 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2041 
  2042 - Locale interpretation commands no longer attempt to simplify goal.
  2043 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2044 methods intro_locales and unfold_locales to clarify.
  2045 
  2046 - Locale interpretation commands no longer accept interpretation
  2047 attributes.  INCOMPATIBILITY.
  2048 
  2049 * Class declaration: so-called "base sort" must not be given in import
  2050 list any longer, but is inferred from the specification.  Particularly
  2051 in HOL, write
  2052 
  2053     class foo = ...
  2054 
  2055 instead of
  2056 
  2057     class foo = type + ...
  2058 
  2059 * Class target: global versions of theorems stemming do not carry a
  2060 parameter prefix any longer.  INCOMPATIBILITY.
  2061 
  2062 * Class 'instance' command no longer accepts attached definitions.
  2063 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2064 
  2065 * Recovered hiding of consts, which was accidentally broken in
  2066 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2067 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2068 
  2069 * Slightly more coherent Pure syntax, with updated documentation in
  2070 isar-ref manual.  Removed locales meta_term_syntax and
  2071 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2072 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2073 directly in regular applications.
  2074 
  2075 * There is a new syntactic category "float_const" for signed decimal
  2076 fractions (e.g. 123.45 or -123.45).
  2077 
  2078 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2079 interface with 'setup' command instead.
  2080 
  2081 * Command 'local_setup' is similar to 'setup', but operates on a local
  2082 theory context.
  2083 
  2084 * The 'axiomatization' command now only works within a global theory
  2085 context.  INCOMPATIBILITY.
  2086 
  2087 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2088 hypotheses.  Sorts required in the course of reasoning need to be
  2089 covered by the constraints in the initial statement, completed by the
  2090 type instance information of the background theory.  Non-trivial sort
  2091 hypotheses, which rarely occur in practice, may be specified via
  2092 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2093 
  2094   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2095 
  2096 The result contains an implicit sort hypotheses as before --
  2097 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2098 normalization.
  2099 
  2100 * Generalized Isar history, with support for linear undo, direct state
  2101 addressing etc.
  2102 
  2103 * Changed defaults for unify configuration options:
  2104 
  2105   unify_trace_bound = 50 (formerly 25)
  2106   unify_search_bound = 60 (formerly 30)
  2107 
  2108 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2109 
  2110   a) On theory merge, the last set of code equations for a particular
  2111      constant is taken (in accordance with the policy applied by other
  2112      parts of the code generator framework).
  2113 
  2114   b) Code equations stemming from explicit declarations (e.g. code
  2115      attribute) gain priority over default code equations stemming
  2116      from definition, primrec, fun etc.
  2117 
  2118 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2119 
  2120 * Unified theorem tables for both code generators.  Thus [code
  2121 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2122 
  2123 * Command 'find_consts' searches for constants based on type and name
  2124 patterns, e.g.
  2125 
  2126     find_consts "_ => bool"
  2127 
  2128 By default, matching is against subtypes, but it may be restricted to
  2129 the whole type.  Searching by name is possible.  Multiple queries are
  2130 conjunctive and queries may be negated by prefixing them with a
  2131 hyphen:
  2132 
  2133     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2134 
  2135 * New 'find_theorems' criterion "solves" matches theorems that
  2136 directly solve the current goal (modulo higher-order unification).
  2137 
  2138 * Auto solve feature for main theorem statements: whenever a new goal
  2139 is stated, "find_theorems solves" is called; any theorems that could
  2140 solve the lemma directly are listed as part of the goal state.
  2141 Cf. associated options in Proof General Isabelle settings menu,
  2142 enabled by default, with reasonable timeout for pathological cases of
  2143 higher-order unification.
  2144 
  2145 
  2146 *** Document preparation ***
  2147 
  2148 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2149 demanding keyword 'by' and supporting the full method expression
  2150 syntax just like the Isar command 'by'.
  2151 
  2152 
  2153 *** HOL ***
  2154 
  2155 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2156 points Main and Complex_Main remain as before.
  2157 
  2158 * Logic image HOL-Plain provides a minimal HOL with the most important
  2159 tools available (inductive, datatype, primrec, ...).  This facilitates
  2160 experimentation and tool development.  Note that user applications
  2161 (and library theories) should never refer to anything below theory
  2162 Main, as before.
  2163 
  2164 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2165 experimentation due to shorter build times.
  2166 
  2167 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2168 were previously part of former HOL-Complex.  Entry point Hyperreal
  2169 remains valid, but theories formerly using Complex_Main should now use
  2170 new entry point Hypercomplex.
  2171 
  2172 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2173 Posix processes.  Avoids potentially expensive forking of the ML
  2174 process.  New thread-based implementation also works on non-Unix
  2175 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2176 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2177 commands are covered in the isar-ref manual.
  2178 
  2179 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2180 sledgehammer without local ATP installation (Vampire etc.). Other
  2181 provers may be included via suitable ML wrappers, see also
  2182 src/HOL/ATP_Linkup.thy.
  2183 
  2184 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2185 menu.
  2186 
  2187 * The metis method no longer fails because the theorem is too trivial
  2188 (contains the empty clause).
  2189 
  2190 * The metis method now fails in the usual manner, rather than raising
  2191 an exception, if it determines that it cannot prove the theorem.
  2192 
  2193 * Method "coherent" implements a prover for coherent logic (see also
  2194 src/Tools/coherent.ML).
  2195 
  2196 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2197 "undefined" is the right choice to replace "arbitrary", though
  2198 logically there is no difference.  INCOMPATIBILITY.
  2199 
  2200 * Command "value" now integrates different evaluation mechanisms.  The
  2201 result of the first successful evaluation mechanism is printed.  In
  2202 square brackets a particular named evaluation mechanisms may be
  2203 specified (currently, [SML], [code] or [nbe]).  See further
  2204 src/HOL/ex/Eval_Examples.thy.
  2205 
  2206 * Normalization by evaluation now allows non-leftlinear equations.
  2207 Declare with attribute [code nbe].
  2208 
  2209 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2210 as the structured Isar versions "cases" and "induct", cf. the
  2211 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2212 are now presented as a list of individual projections
  2213 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2214 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2215 rare situations a different rule is selected --- notably nested tuple
  2216 elimination instead of former prod.exhaust: use explicit (case_tac t
  2217 rule: prod.exhaust) here.
  2218 
  2219 * Attributes "cases", "induct", "coinduct" support "del" option.
  2220 
  2221 * Removed fact "case_split_thm", which duplicates "case_split".
  2222 
  2223 * The option datatype has been moved to a new theory Option.  Renamed
  2224 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2225 
  2226 * New predicate "strict_mono" classifies strict functions on partial
  2227 orders.  With strict functions on linear orders, reasoning about
  2228 (in)equalities is facilitated by theorems "strict_mono_eq",
  2229 "strict_mono_less_eq" and "strict_mono_less".
  2230 
  2231 * Some set operations are now proper qualified constants with
  2232 authentic syntax.  INCOMPATIBILITY:
  2233 
  2234     op Int ~>   Set.Int
  2235     op Un ~>    Set.Un
  2236     INTER ~>    Set.INTER
  2237     UNION ~>    Set.UNION
  2238     Inter ~>    Set.Inter
  2239     Union ~>    Set.Union
  2240     {} ~>       Set.empty
  2241     UNIV ~>     Set.UNIV
  2242 
  2243 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2244 theory Set.
  2245 
  2246 * Auxiliary class "itself" has disappeared -- classes without any
  2247 parameter are treated as expected by the 'class' command.
  2248 
  2249 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2250 
  2251 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2252 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2253 
  2254 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2255 method "approximation".  It proves formulas on real values by using
  2256 interval arithmetic.  In the formulas are also the transcendental
  2257 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2258 allowed. For examples see
  2259 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2260 
  2261 * Theory "Reflection" now resides in HOL/Library.
  2262 
  2263 * Entry point to Word library now simply named "Word".
  2264 INCOMPATIBILITY.
  2265 
  2266 * Made source layout more coherent with logical distribution
  2267 structure:
  2268 
  2269     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2270     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2271     src/HOL/Library/GCD.thy ~> src/HOL/
  2272     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2273     src/HOL/Library/Parity.thy ~> src/HOL/
  2274     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2275     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2276     src/HOL/Real/Lubs.thy ~> src/HOL/
  2277     src/HOL/Real/PReal.thy ~> src/HOL/
  2278     src/HOL/Real/Rational.thy ~> src/HOL/
  2279     src/HOL/Real/RComplete.thy ~> src/HOL/
  2280     src/HOL/Real/RealDef.thy ~> src/HOL/
  2281     src/HOL/Real/RealPow.thy ~> src/HOL/
  2282     src/HOL/Real/Real.thy ~> src/HOL/
  2283     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2284     src/HOL/Complex/Complex.thy ~> src/HOL/
  2285     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2286     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2287     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2288     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2289     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2290     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2291     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2292     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2293     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2294     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2295     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2296     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2297     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2298     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2299     src/HOL/Real/Float ~> src/HOL/Library/
  2300     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2301     src/HOL/Real/RealVector.thy ~> src/HOL/
  2302 
  2303     src/HOL/arith_data.ML ~> src/HOL/Tools
  2304     src/HOL/hologic.ML ~> src/HOL/Tools
  2305     src/HOL/simpdata.ML ~> src/HOL/Tools
  2306     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2307     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2308     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2309     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2310     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2311     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2312     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2313 
  2314     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2315     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2316     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2317     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2318     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2319     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2320 
  2321 * If methods "eval" and "evaluation" encounter a structured proof
  2322 state with !!/==>, only the conclusion is evaluated to True (if
  2323 possible), avoiding strange error messages.
  2324 
  2325 * Method "sizechange" automates termination proofs using (a
  2326 modification of) the size-change principle.  Requires SAT solver.  See
  2327 src/HOL/ex/Termination.thy for examples.
  2328 
  2329 * Simplifier: simproc for let expressions now unfolds if bound
  2330 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2331 
  2332 * Method "arith": Linear arithmetic now ignores all inequalities when
  2333 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2334 
  2335 * New attribute "arith" for facts that should always be used
  2336 automatically by arithmetic. It is intended to be used locally in
  2337 proofs, e.g.
  2338 
  2339   assumes [arith]: "x > 0"
  2340 
  2341 Global usage is discouraged because of possible performance impact.
  2342 
  2343 * New classes "top" and "bot" with corresponding operations "top" and
  2344 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2345 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2346 
  2347 * Changed definition lemma "less_fun_def" in order to provide an
  2348 instance for preorders on functions; use lemma "less_le" instead.
  2349 INCOMPATIBILITY.
  2350 
  2351 * Theory Orderings: class "wellorder" moved here, with explicit
  2352 induction rule "less_induct" as assumption.  For instantiation of
  2353 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2354 INCOMPATIBILITY.
  2355 
  2356 * Theory Orderings: added class "preorder" as superclass of "order".
  2357 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2358 etc. slightly changed.  Some theorems named order_class.* now named
  2359 preorder_class.*.
  2360 
  2361 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2362 "diag" to "Id_on".
  2363 
  2364 * Theory Finite_Set: added a new fold combinator of type
  2365 
  2366   ('a => 'b => 'b) => 'b => 'a set => 'b
  2367 
  2368 Occasionally this is more convenient than the old fold combinator
  2369 which is now defined in terms of the new one and renamed to
  2370 fold_image.
  2371 
  2372 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2373 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2374 extended with further lemmas!).  At the moment both still exist but
  2375 the former will disappear at some point.
  2376 
  2377 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2378 class recpower.  Type-specific simp rules for various recpower types
  2379 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2380 
  2381 rat_power_0    -> power_0
  2382 rat_power_Suc  -> power_Suc
  2383 realpow_0      -> power_0
  2384 realpow_Suc    -> power_Suc
  2385 complexpow_0   -> power_0
  2386 complexpow_Suc -> power_Suc
  2387 power_poly_0   -> power_0
  2388 power_poly_Suc -> power_Suc
  2389 
  2390 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2391 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2392 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2393 of lemmas from Divides has been generalized from nat to class
  2394 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2395 renames resulting from duplicate elimination:
  2396 
  2397     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2398     zero_dvd_iff ~>         dvd_0_left_iff
  2399     dvd_0 ~>                dvd_0_right
  2400     DIVISION_BY_ZERO_DIV ~> div_by_0
  2401     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2402     mult_div ~>             div_mult_self2_is_id
  2403     mult_mod ~>             mod_mult_self2_is_0
  2404 
  2405 * Theory IntDiv: removed many lemmas that are instances of class-based
  2406 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2407 rename old lemmas as follows:
  2408 
  2409 dvd_diff               -> nat_dvd_diff
  2410 dvd_zminus_iff         -> dvd_minus_iff
  2411 mod_add1_eq            -> mod_add_eq
  2412 mod_mult1_eq           -> mod_mult_right_eq
  2413 mod_mult1_eq'          -> mod_mult_left_eq
  2414 mod_mult_distrib_mod   -> mod_mult_eq
  2415 nat_mod_add_left_eq    -> mod_add_left_eq
  2416 nat_mod_add_right_eq   -> mod_add_right_eq
  2417 nat_mod_div_trivial    -> mod_div_trivial
  2418 nat_mod_mod_trivial    -> mod_mod_trivial
  2419 zdiv_zadd_self1        -> div_add_self1
  2420 zdiv_zadd_self2        -> div_add_self2
  2421 zdiv_zmult_self1       -> div_mult_self2_is_id
  2422 zdiv_zmult_self2       -> div_mult_self1_is_id
  2423 zdvd_triv_left         -> dvd_triv_left
  2424 zdvd_triv_right        -> dvd_triv_right
  2425 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2426 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2427 zmod_zadd_left_eq      -> mod_add_left_eq
  2428 zmod_zadd_right_eq     -> mod_add_right_eq
  2429 zmod_zadd_self1        -> mod_add_self1
  2430 zmod_zadd_self2        -> mod_add_self2
  2431 zmod_zadd1_eq          -> mod_add_eq
  2432 zmod_zdiff1_eq         -> mod_diff_eq
  2433 zmod_zdvd_zmod         -> mod_mod_cancel
  2434 zmod_zmod_cancel       -> mod_mod_cancel
  2435 zmod_zmult_self1       -> mod_mult_self2_is_0
  2436 zmod_zmult_self2       -> mod_mult_self1_is_0
  2437 zmod_1                 -> mod_by_1
  2438 zdiv_1                 -> div_by_1
  2439 zdvd_abs1              -> abs_dvd_iff
  2440 zdvd_abs2              -> dvd_abs_iff
  2441 zdvd_refl              -> dvd_refl
  2442 zdvd_trans             -> dvd_trans
  2443 zdvd_zadd              -> dvd_add
  2444 zdvd_zdiff             -> dvd_diff
  2445 zdvd_zminus_iff        -> dvd_minus_iff
  2446 zdvd_zminus2_iff       -> minus_dvd_iff
  2447 zdvd_zmultD            -> dvd_mult_right
  2448 zdvd_zmultD2           -> dvd_mult_left
  2449 zdvd_zmult_mono        -> mult_dvd_mono
  2450 zdvd_0_right           -> dvd_0_right
  2451 zdvd_0_left            -> dvd_0_left_iff
  2452 zdvd_1_left            -> one_dvd
  2453 zminus_dvd_iff         -> minus_dvd_iff
  2454 
  2455 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2456 
  2457 * The real numbers offer decimal input syntax: 12.34 is translated
  2458 into 1234/10^2. This translation is not reversed upon output.
  2459 
  2460 * Theory Library/Polynomial defines an abstract type 'a poly of
  2461 univariate polynomials with coefficients of type 'a.  In addition to
  2462 the standard ring operations, it also supports div and mod.  Code
  2463 generation is also supported, using list-style constructors.
  2464 
  2465 * Theory Library/Inner_Product defines a class of real_inner for real
  2466 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2467 => real.  Class real_inner is a subclass of real_normed_vector from
  2468 theory RealVector.
  2469 
  2470 * Theory Library/Product_Vector provides instances for the product
  2471 type 'a * 'b of several classes from RealVector and Inner_Product.
  2472 Definitions of addition, subtraction, scalar multiplication, norms,
  2473 and inner products are included.
  2474 
  2475 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2476 addition to the field operations, numerals and case syntax are also
  2477 supported.
  2478 
  2479 * Theory Library/Diagonalize provides constructive version of Cantor's
  2480 first diagonalization argument.
  2481 
  2482 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2483 zlcm (for int); carried together from various gcd/lcm developements in
  2484 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2485 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2486 may recover tupled syntax as follows:
  2487 
  2488     hide (open) const gcd
  2489     abbreviation gcd where
  2490       "gcd == (%(a, b). GCD.gcd a b)"
  2491     notation (output)
  2492       GCD.gcd ("gcd '(_, _')")
  2493 
  2494 The same works for lcm, zgcd, zlcm.
  2495 
  2496 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2497 instantiations for algebraic structures.  Removed some duplicate
  2498 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2499 
  2500 * ML antiquotation @{code} takes a constant as argument and generates
  2501 corresponding code in background and inserts name of the corresponding
  2502 resulting ML value/function/datatype constructor binding in place.
  2503 All occurrences of @{code} with a single ML block are generated
  2504 simultaneously.  Provides a generic and safe interface for
  2505 instrumentalizing code generation.  See
  2506 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2507 In future you ought to refrain from ad-hoc compiling generated SML
  2508 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2509 cannot refer to constants for which user-defined serializations are
  2510 set.  Refer to the corresponding ML counterpart directly in that
  2511 cases.
  2512 
  2513 * Command 'rep_datatype': instead of theorem names the command now
  2514 takes a list of terms denoting the constructors of the type to be
  2515 represented as datatype.  The characteristic theorems have to be
  2516 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2517 have disappeared in favour of existing ones:
  2518 
  2519     unit_induct                 ~> unit.induct
  2520     prod_induct                 ~> prod.induct
  2521     sum_induct                  ~> sum.induct
  2522     Suc_Suc_eq                  ~> nat.inject
  2523     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2524 
  2525 
  2526 *** HOL-Algebra ***
  2527 
  2528 * New locales for orders and lattices where the equivalence relation
  2529 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2530 locales use a record structure with field eq for the equivalence.
  2531 
  2532 * New theory of factorial domains.
  2533 
  2534 * Units_l_inv and Units_r_inv are now simp rules by default.
  2535 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2536 and/or r_inv will now also require deletion of these lemmas.
  2537 
  2538 * Renamed the following theorems, INCOMPATIBILITY:
  2539 
  2540 UpperD ~> Upper_memD
  2541 LowerD ~> Lower_memD
  2542 least_carrier ~> least_closed
  2543 greatest_carrier ~> greatest_closed
  2544 greatest_Lower_above ~> greatest_Lower_below
  2545 one_zero ~> carrier_one_zero
  2546 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2547 
  2548 
  2549 *** HOL-Nominal ***
  2550 
  2551 * Nominal datatypes can now contain type-variables.
  2552 
  2553 * Commands 'nominal_inductive' and 'equivariance' work with local
  2554 theory targets.
  2555 
  2556 * Nominal primrec can now works with local theory targets and its
  2557 specification syntax now conforms to the general format as seen in
  2558 'inductive' etc.
  2559 
  2560 * Method "perm_simp" honours the standard simplifier attributes
  2561 (no_asm), (no_asm_use) etc.
  2562 
  2563 * The new predicate #* is defined like freshness, except that on the
  2564 left hand side can be a set or list of atoms.
  2565 
  2566 * Experimental command 'nominal_inductive2' derives strong induction
  2567 principles for inductive definitions.  In contrast to
  2568 'nominal_inductive', which can only deal with a fixed number of
  2569 binders, it can deal with arbitrary expressions standing for sets of
  2570 atoms to be avoided.  The only inductive definition we have at the
  2571 moment that needs this generalisation is the typing rule for Lets in
  2572 the algorithm W:
  2573 
  2574  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2575  -----------------------------------------------------------------
  2576          Gamma |- Let x be t1 in t2 : T2
  2577 
  2578 In this rule one wants to avoid all the binders that are introduced by
  2579 "close Gamma T1".  We are looking for other examples where this
  2580 feature might be useful.  Please let us know.
  2581 
  2582 
  2583 *** HOLCF ***
  2584 
  2585 * Reimplemented the simplification procedure for proving continuity
  2586 subgoals.  The new simproc is extensible; users can declare additional
  2587 continuity introduction rules with the attribute [cont2cont].
  2588 
  2589 * The continuity simproc now uses a different introduction rule for
  2590 solving continuity subgoals on terms with lambda abstractions.  In
  2591 some rare cases the new simproc may fail to solve subgoals that the
  2592 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2593 Potential INCOMPATIBILITY.
  2594 
  2595 * Command 'fixrec': specification syntax now conforms to the general
  2596 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2597 examples.  INCOMPATIBILITY.
  2598 
  2599 
  2600 *** ZF ***
  2601 
  2602 * Proof of Zorn's Lemma for partial orders.
  2603 
  2604 
  2605 *** ML ***
  2606 
  2607 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2608 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2609 depends on multithreading, so timouts will not work before Poly/ML
  2610 5.2.1!
  2611 
  2612 * High-level support for concurrent ML programming, see
  2613 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2614 particularly convenient to organize independent functional
  2615 computations.  The concept of "synchronized variables" provides a
  2616 higher-order interface for components with shared state, avoiding the
  2617 delicate details of mutexes and condition variables.  (Requires
  2618 Poly/ML 5.2.1 or later.)
  2619 
  2620 * ML bindings produced via Isar commands are stored within the Isar
  2621 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2622 become thread-safe and work with undo as expected (concerning
  2623 top-level bindings, not side-effects on global references).
  2624 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2625 compiler at runtime; really global bindings need to be given outside a
  2626 theory.  (Requires Poly/ML 5.2 or later.)
  2627 
  2628 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2629 context.  Top-level ML bindings are stored within the proof context in
  2630 a purely sequential fashion, disregarding the nested proof structure.
  2631 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2632 proof.  (Requires Poly/ML 5.2 or later.)
  2633 
  2634 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2635 and Method.setup, as well as Isar commands 'attribute_setup' and
  2636 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2637 existing code accordingly, or use plain 'setup' together with old
  2638 Method.add_method.
  2639 
  2640 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2641 to 'a -> thm, while results are always tagged with an authentic oracle
  2642 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2643 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2644 accordingly.  Note that extra performance may be gained by producing
  2645 the cterm carefully, avoiding slow Thm.cterm_of.
  2646 
  2647 * Simplified interface for defining document antiquotations via
  2648 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2649 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2650 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2651 examples.
  2652 
  2653 * More systematic treatment of long names, abstract name bindings, and
  2654 name space operations.  Basic operations on qualified names have been
  2655 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2656 Long_Name.append.  Old type bstring has been mostly replaced by
  2657 abstract type binding (see structure Binding), which supports precise
  2658 qualification by packages and local theory targets, as well as proper
  2659 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2660 bstring values into Binding.name, or better pass through abstract
  2661 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2662 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2663 
  2664 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2665 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2666 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2667 
  2668 * Disposed old type and term read functions (Sign.read_def_typ,
  2669 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2670 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2671 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2672 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2673 resort for legacy applications.
  2674 
  2675 * Disposed old declarations, tactics, tactic combinators that refer to
  2676 the simpset or claset of an implicit theory (such as Addsimps,
  2677 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2678 embedded ML text, or local_simpset_of with a proper context passed as
  2679 explicit runtime argument.
  2680 
  2681 * Rules and tactics that read instantiations (read_instantiate,
  2682 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2683 context, which is required for parsing and type-checking.  Moreover,
  2684 the variables are specified as plain indexnames, not string encodings
  2685 thereof.  INCOMPATIBILITY.
  2686 
  2687 * Generic Toplevel.add_hook interface allows to analyze the result of
  2688 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2689 for theorem dependency output of transactions resulting in a new
  2690 theory state.
  2691 
  2692 * ML antiquotations: block-structured compilation context indicated by
  2693 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2694 
  2695   @{binding name}                         - basic name binding
  2696   @{let ?pat = term}                      - term abbreviation (HO matching)
  2697   @{note name = fact}                     - fact abbreviation
  2698   @{thm fact}                             - singleton fact (with attributes)
  2699   @{thms fact}                            - general fact (with attributes)
  2700   @{lemma prop by method}                 - singleton goal
  2701   @{lemma prop by meth1 meth2}            - singleton goal
  2702   @{lemma prop1 ... propN by method}      - general goal
  2703   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2704   @{lemma (open) ...}                     - open derivation
  2705 
  2706 
  2707 *** System ***
  2708 
  2709 * The Isabelle "emacs" tool provides a specific interface to invoke
  2710 Proof General / Emacs, with more explicit failure if that is not
  2711 installed (the old isabelle-interface script silently falls back on
  2712 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2713 installation location of the Proof General distribution.
  2714 
  2715 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2716 the Isabelle process into a JVM/Scala application.  See
  2717 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2718 process wrapper has been discontinued.)
  2719 
  2720 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2721 
  2722 * Various status messages (with exact source position information) are
  2723 emitted, if proper markup print mode is enabled.  This allows
  2724 user-interface components to provide detailed feedback on internal
  2725 prover operations.
  2726 
  2727 
  2728 
  2729 New in Isabelle2008 (June 2008)
  2730 -------------------------------
  2731 
  2732 *** General ***
  2733 
  2734 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2735 and updated, with formally checked references as hyperlinks.
  2736 
  2737 * Theory loader: use_thy (and similar operations) no longer set the
  2738 implicit ML context, which was occasionally hard to predict and in
  2739 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2740 provides a proper context already.
  2741 
  2742 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2743 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2744 'use' within a theory file will do the job.
  2745 
  2746 * Name space merge now observes canonical order, i.e. the second space
  2747 is inserted into the first one, while existing entries in the first
  2748 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2749 swap theory imports.
  2750 
  2751 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2752 INCOMPATIBILITY in identifier syntax etc.
  2753 
  2754 * Outer syntax: string tokens no longer admit escaped white space,
  2755 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2756 white space without escapes.
  2757 
  2758 * Outer syntax: string tokens may contain arbitrary character codes
  2759 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2760 "foo_bar".
  2761 
  2762 
  2763 *** Pure ***
  2764 
  2765 * Context-dependent token translations.  Default setup reverts locally
  2766 fixed variables, and adds hilite markup for undeclared frees.
  2767 
  2768 * Unused theorems can be found using the new command 'unused_thms'.
  2769 There are three ways of invoking it:
  2770 
  2771 (1) unused_thms
  2772      Only finds unused theorems in the current theory.
  2773 
  2774 (2) unused_thms thy_1 ... thy_n -
  2775      Finds unused theorems in the current theory and all of its ancestors,
  2776      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2777 
  2778 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2779      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2780      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2781      their ancestors.
  2782 
  2783 In order to increase the readability of the list produced by
  2784 unused_thms, theorems that have been created by a particular instance
  2785 of a theory command such as 'inductive' or 'function' are considered
  2786 to belong to the same "group", meaning that if at least one theorem in
  2787 this group is used, the other theorems in the same group are no longer
  2788 reported as unused.  Moreover, if all theorems in the group are
  2789 unused, only one theorem in the group is displayed.
  2790 
  2791 Note that proof objects have to be switched on in order for
  2792 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2793 usually the case when using Proof General with the default settings).
  2794 
  2795 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2796 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2797 duplicate fact bindings, or even accidental fact duplications.  Note
  2798 that tools may maintain dynamically scoped facts systematically, using
  2799 PureThy.add_thms_dynamic.
  2800 
  2801 * Command 'hide' now allows to hide from "fact" name space as well.
  2802 
  2803 * Eliminated destructive theorem database, simpset, claset, and
  2804 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2805 update of theories within ML code.
  2806 
  2807 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2808 INCOMPATIBILITY, object-logics depending on former Pure require
  2809 additional setup PureThy.old_appl_syntax_setup; object-logics
  2810 depending on former CPure need to refer to Pure.
  2811 
  2812 * Commands 'use' and 'ML' are now purely functional, operating on
  2813 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2814 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2815 INCOMPATIBILITY.
  2816 
  2817 * Command 'setup': discontinued implicit version with ML reference.
  2818 
  2819 * Instantiation target allows for simultaneous specification of class
  2820 instance operations together with an instantiation proof.
  2821 Type-checking phase allows to refer to class operations uniformly.
  2822 See src/HOL/Complex/Complex.thy for an Isar example and
  2823 src/HOL/Library/Eval.thy for an ML example.
  2824 
  2825 * Indexing of literal facts: be more serious about including only
  2826 facts from the visible specification/proof context, but not the
  2827 background context (locale etc.).  Affects `prop` notation and method
  2828 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2829 situations.
  2830 
  2831 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2832 "(open)" option, which used to expose internal bound variables to the
  2833 proof text.
  2834 
  2835 * Isar statements: removed obsolete case "rule_context".
  2836 INCOMPATIBILITY, better use explicit fixes/assumes.
  2837 
  2838 * Locale proofs: default proof step now includes 'unfold_locales';
  2839 hence 'proof' without argument may be used to unfold locale
  2840 predicates.
  2841 
  2842 
  2843 *** Document preparation ***
  2844 
  2845 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2846 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2847 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2848 spot); renamed link color from "darkblue" to "linkcolor" (default
  2849 value unchanged, can be redefined via \definecolor); no longer sets
  2850 "a4paper" option (unnecessary or even intrusive).
  2851 
  2852 * Antiquotation @{lemma A method} proves proposition A by the given
  2853 method (either a method name or a method name plus (optional) method
  2854 arguments in parentheses) and prints A just like @{prop A}.
  2855 
  2856 
  2857 *** HOL ***
  2858 
  2859 * New primrec package.  Specification syntax conforms in style to
  2860 definition/function/....  No separate induction rule is provided.  The
  2861 "primrec" command distinguishes old-style and new-style specifications
  2862 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2863 When adjusting theories, beware: constants stemming from new-style
  2864 primrec specifications have authentic syntax.
  2865 
  2866 * Metis prover is now an order of magnitude faster, and also works
  2867 with multithreading.
  2868 
  2869 * Metis: the maximum number of clauses that can be produced from a
  2870 theorem is now given by the attribute max_clauses.  Theorems that
  2871 exceed this number are ignored, with a warning printed.
  2872 
  2873 * Sledgehammer no longer produces structured proofs by default. To
  2874 enable, declare [[sledgehammer_full = true]].  Attributes
  2875 reconstruction_modulus, reconstruction_sorts renamed
  2876 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2877 
  2878 * Method "induct_scheme" derives user-specified induction rules
  2879 from well-founded induction and completeness of patterns. This factors
  2880 out some operations that are done internally by the function package
  2881 and makes them available separately.  See
  2882 src/HOL/ex/Induction_Scheme.thy for examples.
  2883 
  2884 * More flexible generation of measure functions for termination
  2885 proofs: Measure functions can be declared by proving a rule of the
  2886 form "is_measure f" and giving it the [measure_function] attribute.
  2887 The "is_measure" predicate is logically meaningless (always true), and
  2888 just guides the heuristic.  To find suitable measure functions, the
  2889 termination prover sets up the goal "is_measure ?f" of the appropriate
  2890 type and generates all solutions by prolog-style backwards proof using
  2891 the declared rules.
  2892 
  2893 This setup also deals with rules like 
  2894 
  2895   "is_measure f ==> is_measure (list_size f)"
  2896 
  2897 which accommodates nested datatypes that recurse through lists.
  2898 Similar rules are predeclared for products and option types.
  2899 
  2900 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2901 
  2902   INCOMPATIBILITIES:
  2903 
  2904   - Definitions of overloaded constants on sets have to be replaced by
  2905     definitions on => and bool.
  2906 
  2907   - Some definitions of overloaded operators on sets can now be proved
  2908     using the definitions of the operators on => and bool.  Therefore,
  2909     the following theorems have been renamed:
  2910 
  2911       subset_def   -> subset_eq
  2912       psubset_def  -> psubset_eq
  2913       set_diff_def -> set_diff_eq
  2914       Compl_def    -> Compl_eq
  2915       Sup_set_def  -> Sup_set_eq
  2916       Inf_set_def  -> Inf_set_eq
  2917       sup_set_def  -> sup_set_eq
  2918       inf_set_def  -> inf_set_eq
  2919 
  2920   - Due to the incompleteness of the HO unification algorithm, some
  2921     rules such as subst may require manual instantiation, if some of
  2922     the unknowns in the rule is a set.
  2923 
  2924   - Higher order unification and forward proofs:
  2925     The proof pattern
  2926 
  2927       have "P (S::'a set)" <...>
  2928       then have "EX S. P S" ..
  2929 
  2930     no longer works (due to the incompleteness of the HO unification
  2931     algorithm) and must be replaced by the pattern
  2932 
  2933       have "EX S. P S"
  2934       proof
  2935         show "P S" <...>
  2936       qed
  2937 
  2938   - Calculational reasoning with subst (or similar rules):
  2939     The proof pattern
  2940 
  2941       have "P (S::'a set)" <...>
  2942       also have "S = T" <...>
  2943       finally have "P T" .
  2944 
  2945     no longer works (for similar reasons as the previous example) and
  2946     must be replaced by something like
  2947 
  2948       have "P (S::'a set)" <...>
  2949       moreover have "S = T" <...>
  2950       ultimately have "P T" by simp
  2951 
  2952   - Tactics or packages written in ML code:
  2953     Code performing pattern matching on types via
  2954 
  2955       Type ("set", [T]) => ...
  2956 
  2957     must be rewritten. Moreover, functions like strip_type or
  2958     binder_types no longer return the right value when applied to a
  2959     type of the form
  2960 
  2961       T1 => ... => Tn => U => bool
  2962 
  2963     rather than
  2964 
  2965       T1 => ... => Tn => U set
  2966 
  2967 * Merged theories Wellfounded_Recursion, Accessible_Part and
  2968 Wellfounded_Relations to theory Wellfounded.
  2969 
  2970 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  2971 
  2972 * Class finite no longer treats UNIV as class parameter.  Use class
  2973 enum from theory Library/Enum instead to achieve a similar effect.
  2974 INCOMPATIBILITY.
  2975 
  2976 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  2977 and "Cons".  INCOMPATIBILITY.
  2978 
  2979 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  2980 Potential INCOMPATIBILITY.
  2981 
  2982 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  2983 injective_fst_snd removed, use split_eta and prod_eqI instead.
  2984 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  2985 
  2986 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  2987 the same name in theory Orderings:
  2988 
  2989   less_trans
  2990   less_linear
  2991   le_imp_less_or_eq
  2992   le_less_trans
  2993   less_le_trans
  2994   less_not_sym
  2995   less_asym
  2996 
  2997 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  2998 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  2999 and different variable names.
  3000 
  3001 * Library/Option_ord.thy: Canonical order on option type.
  3002 
  3003 * Library/RBT.thy: Red-black trees, an efficient implementation of
  3004 finite maps.
  3005 
  3006 * Library/Countable.thy: Type class for countable types.
  3007 
  3008 * Theory Int: The representation of numerals has changed.  The infix
  3009 operator BIT and the bit datatype with constructors B0 and B1 have
  3010 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  3011 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  3012 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  3013 accordingly.
  3014 
  3015 * Theory Nat: definition of <= and < on natural numbers no longer
  3016 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  3017 le_def and less_def have disappeared.  Consider lemmas not_less
  3018 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  3019 
  3020 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  3021 (whose purpose mainly is for various fold_set functionals) have been
  3022 abandoned in favor of the existing algebraic classes
  3023 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  3024 lower_semilattice (resp. upper_semilattice) and linorder.
  3025 INCOMPATIBILITY.
  3026 
  3027 * Theory Transitive_Closure: induct and cases rules now declare proper
  3028 case_names ("base" and "step").  INCOMPATIBILITY.
  3029 
  3030 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  3031 lattices.  The form set-specific version is available as
  3032 Inductive.lfp_ordinal_induct_set.
  3033 
  3034 * Renamed theorems "power.simps" to "power_int.simps".
  3035 INCOMPATIBILITY.
  3036 
  3037 * Class semiring_div provides basic abstract properties of semirings
  3038 with division and modulo operations.  Subsumes former class dvd_mod.
  3039 
  3040 * Merged theories IntDef, Numeral and IntArith into unified theory
  3041 Int.  INCOMPATIBILITY.
  3042 
  3043 * Theory Library/Code_Index: type "index" now represents natural
  3044 numbers rather than integers.  INCOMPATIBILITY.
  3045 
  3046 * New class "uminus" with operation "uminus" (split of from class
  3047 "minus" which now only has operation "minus", binary).
  3048 INCOMPATIBILITY.
  3049 
  3050 * Constants "card", "internal_split", "option_map" now with authentic
  3051 syntax.  INCOMPATIBILITY.
  3052 
  3053 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3054 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3055 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3056 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3057 Sup_set_def, le_def, less_def, option_map_def now with object
  3058 equality.  INCOMPATIBILITY.
  3059 
  3060 * Records. Removed K_record, and replaced it by pure lambda term
  3061 %x. c. The simplifier setup is now more robust against eta expansion.
  3062 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3063 
  3064 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3065 
  3066 * Library/ListVector: new theory of arithmetic vector operations.
  3067 
  3068 * Library/Order_Relation: new theory of various orderings as sets of
  3069 pairs.  Defines preorders, partial orders, linear orders and
  3070 well-orders on sets and on types.
  3071 
  3072 
  3073 *** ZF ***
  3074 
  3075 * Renamed some theories to allow to loading both ZF and HOL in the
  3076 same session:
  3077 
  3078   Datatype  -> Datatype_ZF
  3079   Inductive -> Inductive_ZF
  3080   Int       -> Int_ZF
  3081   IntDiv    -> IntDiv_ZF
  3082   Nat       -> Nat_ZF
  3083   List      -> List_ZF
  3084   Main      -> Main_ZF
  3085 
  3086 INCOMPATIBILITY: ZF theories that import individual theories below
  3087 Main might need to be adapted.  Regular theory Main is still
  3088 available, as trivial extension of Main_ZF.
  3089 
  3090 
  3091 *** ML ***
  3092 
  3093 * ML within Isar: antiquotation @{const name} or @{const
  3094 name(typargs)} produces statically-checked Const term.
  3095 
  3096 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3097 (of the same name).  Removed obsolete print command.
  3098 
  3099 * Removed obsolete "use_legacy_bindings" function.
  3100 
  3101 * The ``print mode'' is now a thread-local value derived from a global
  3102 template (the former print_mode reference), thus access becomes
  3103 non-critical.  The global print_mode reference is for session
  3104 management only; user-code should use print_mode_value,
  3105 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3106 
  3107 * Functions system/system_out provide a robust way to invoke external
  3108 shell commands, with propagation of interrupts (requires Poly/ML
  3109 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3110 
  3111 
  3112 *** System ***
  3113 
  3114 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3115 in accordance with Proof General 3.7, which prefers GNU emacs.
  3116 
  3117 * isatool tty runs Isabelle process with plain tty interaction;
  3118 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3119 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3120 
  3121 * isatool browser now works with Cygwin as well, using general
  3122 "javapath" function defined in Isabelle process environment.
  3123 
  3124 * YXML notation provides a simple and efficient alternative to
  3125 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3126 isatool yxml as described in the Isabelle system manual.
  3127 
  3128 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3129 provides general wrapper for managing an Isabelle process in a robust
  3130 fashion, with ``cooked'' output from stdin/stderr.
  3131 
  3132 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3133 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3134 
  3135 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3136 way of changing the user's settings is via
  3137 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3138 script.
  3139 
  3140 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3141 cores of the underlying machine, which is a good starting point for
  3142 optimal performance tuning.  The corresponding usedir option -M allows
  3143 "max" as an alias for "0".  WARNING: does not work on certain versions
  3144 of Mac OS (with Poly/ML 5.1).
  3145 
  3146 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3147 adverse effect of Isabelle flooding interactive front-ends (notably
  3148 ProofGeneral / XEmacs).
  3149 
  3150 
  3151 
  3152 New in Isabelle2007 (November 2007)
  3153 -----------------------------------
  3154 
  3155 *** General ***
  3156 
  3157 * More uniform information about legacy features, notably a
  3158 warning/error of "Legacy feature: ...", depending on the state of the
  3159 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3160 legacy features will disappear eventually.
  3161 
  3162 * Theory syntax: the header format ``theory A = B + C:'' has been
  3163 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3164 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3165 
  3166 * Theory syntax: the old non-Isar theory file format has been
  3167 discontinued altogether.  Note that ML proof scripts may still be used
  3168 with Isar theories; migration is usually quite simple with the ML
  3169 function use_legacy_bindings.  INCOMPATIBILITY.
  3170 
  3171 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3172 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3173 quotes.
  3174 
  3175 * Theory loader: be more serious about observing the static theory
  3176 header specifications (including optional directories), but not the
  3177 accidental file locations of previously successful loads.  The strict
  3178 update policy of former update_thy is now already performed by
  3179 use_thy, so the former has been removed; use_thys updates several
  3180 theories simultaneously, just as 'imports' within a theory header
  3181 specification, but without merging the results.  Potential
  3182 INCOMPATIBILITY: may need to refine theory headers and commands
  3183 ROOT.ML which depend on load order.
  3184 
  3185 * Theory loader: optional support for content-based file
  3186 identification, instead of the traditional scheme of full physical
  3187 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3188 (cf. the system manual).  The new scheme allows to work with
  3189 non-finished theories in persistent session images, such that source
  3190 files may be moved later on without requiring reloads.
  3191 
  3192 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3193 file (with the same base name as the theory) are considered a legacy
  3194 feature, which will disappear eventually. Even now, the theory loader
  3195 no longer maintains dependencies on such files.
  3196 
  3197 * Syntax: the scope for resolving ambiguities via type-inference is
  3198 now limited to individual terms, instead of whole simultaneous
  3199 specifications as before. This greatly reduces the complexity of the
  3200 syntax module and improves flexibility by separating parsing and
  3201 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3202 'fixes' etc.) are required in rare situations.
  3203 
  3204 * Syntax: constants introduced by new-style packages ('definition',
  3205 'abbreviation' etc.) are passed through the syntax module in
  3206 ``authentic mode''. This means that associated mixfix annotations
  3207 really stick to such constants, independently of potential name space
  3208 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3209 trees are represented slightly differently, may need to adapt syntax
  3210 translations accordingly. Use CONST marker in 'translations' and
  3211 @{const_syntax} antiquotation in 'parse_translation' etc.
  3212 
  3213 * Legacy goal package: reduced interface to the bare minimum required
  3214 to keep existing proof scripts running.  Most other user-level
  3215 functions are now part of the OldGoals structure, which is *not* open
  3216 by default (consider isatool expandshort before open OldGoals).
  3217 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3218 these tend to cause confusion about the actual goal (!) context being
  3219 used here, which is not necessarily the same as the_context().
  3220 
  3221 * Command 'find_theorems': supports "*" wild-card in "name:"
  3222 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3223 support a specific search form (see ProofGeneral/CHANGES).
  3224 
  3225 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3226 by default, which means that "prems" (and also "fixed variables") are
  3227 suppressed from proof state output.  Note that the ProofGeneral
  3228 settings mechanism allows to change and save options persistently, but
  3229 older versions of Isabelle will fail to start up if a negative prems
  3230 limit is imposed.
  3231 
  3232 * Local theory targets may be specified by non-nested blocks of
  3233 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3234 contain definitions, theorems etc., including any derived mechanism
  3235 that has been implemented on top of these primitives.  This concept
  3236 generalizes the existing ``theorem (in ...)'' towards more versatility
  3237 and scalability.
  3238 
  3239 * Proof General interface: proper undo of final 'end' command;
  3240 discontinued Isabelle/classic mode (ML proof scripts).
  3241 
  3242 
  3243 *** Document preparation ***
  3244 
  3245 * Added antiquotation @{theory name} which prints the given name,
  3246 after checking that it refers to a valid ancestor theory in the
  3247 current context.
  3248 
  3249 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3250 check the given source text as ML type/structure, printing verbatim.
  3251 
  3252 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3253 "c args == rhs" given in the current context.  (Any number of
  3254 arguments may be given on the LHS.)
  3255 
  3256 
  3257 *** Pure ***
  3258 
  3259 * The 'class' package offers a combination of axclass and locale to
  3260 achieve Haskell-like type classes in Isabelle.  Definitions and
  3261 theorems within a class context produce both relative results (with
  3262 implicit parameters according to the locale context), and polymorphic
  3263 constants with qualified polymorphism (according to the class
  3264 context).  Within the body context of a 'class' target, a separate
  3265 syntax layer ("user space type system") takes care of converting
  3266 between global polymorphic consts and internal locale representation.
  3267 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3268 "isatool doc classes" provides a tutorial.
  3269 
  3270 * Generic code generator framework allows to generate executable
  3271 code for ML and Haskell (including Isabelle classes).  A short usage
  3272 sketch:
  3273 
  3274     internal compilation:
  3275         export_code <list of constants (term syntax)> in SML
  3276     writing SML code to a file:
  3277         export_code <list of constants (term syntax)> in SML <filename>
  3278     writing OCaml code to a file:
  3279         export_code <list of constants (term syntax)> in OCaml <filename>
  3280     writing Haskell code to a bunch of files:
  3281         export_code <list of constants (term syntax)> in Haskell <filename>
  3282 
  3283     evaluating closed propositions to True/False using code generation:
  3284         method ``eval''
  3285 
  3286 Reasonable default setup of framework in HOL.
  3287 
  3288 Theorem attributs for selecting and transforming function equations theorems:
  3289 
  3290     [code fun]:        select a theorem as function equation for a specific constant
  3291     [code fun del]:    deselect a theorem as function equation for a specific constant
  3292     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3293     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3294 
  3295 User-defined serializations (target in {SML, OCaml, Haskell}):
  3296 
  3297     code_const <and-list of constants (term syntax)>
  3298       {(target) <and-list of const target syntax>}+
  3299 
  3300     code_type <and-list of type constructors>
  3301       {(target) <and-list of type target syntax>}+
  3302 
  3303     code_instance <and-list of instances>
  3304       {(target)}+
  3305         where instance ::= <type constructor> :: <class>
  3306 
  3307     code_class <and_list of classes>
  3308       {(target) <and-list of class target syntax>}+
  3309         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3310 
  3311 code_instance and code_class only are effective to target Haskell.
  3312 
  3313 For example usage see src/HOL/ex/Codegenerator.thy and
  3314 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3315 generation from Isabelle/HOL theories is available via "isatool doc
  3316 codegen".
  3317 
  3318 * Code generator: consts in 'consts_code' Isar commands are now
  3319 referred to by usual term syntax (including optional type
  3320 annotations).
  3321 
  3322 * Command 'no_translations' removes translation rules from theory
  3323 syntax.
  3324 
  3325 * Overloaded definitions are now actually checked for acyclic
  3326 dependencies.  The overloading scheme is slightly more general than
  3327 that of Haskell98, although Isabelle does not demand an exact
  3328 correspondence to type class and instance declarations.
  3329 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3330 exotic versions of overloading -- at the discretion of the user!
  3331 
  3332 Polymorphic constants are represented via type arguments, i.e. the
  3333 instantiation that matches an instance against the most general
  3334 declaration given in the signature.  For example, with the declaration
  3335 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3336 as c(nat).  Overloading is essentially simultaneous structural
  3337 recursion over such type arguments.  Incomplete specification patterns
  3338 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3339 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3340 Command 'print_theory' outputs the normalized system of recursive
  3341 equations, see section "definitions".
  3342 
  3343 * Configuration options are maintained within the theory or proof
  3344 context (with name and type bool/int/string), providing a very simple
  3345 interface to a poor-man's version of general context data.  Tools may
  3346 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3347 these values using Config.get etc.  Users may change options via an
  3348 associated attribute of the same name.  This form of context
  3349 declaration works particularly well with commands 'declare' or
  3350 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3351 very easy to avoid global references, which would not observe Isar
  3352 toplevel undo/redo and fail to work with multithreading.
  3353 
  3354 Various global ML references of Pure and HOL have been turned into
  3355 configuration options:
  3356 
  3357   Unify.search_bound		unify_search_bound
  3358   Unify.trace_bound		unify_trace_bound
  3359   Unify.trace_simp		unify_trace_simp
  3360   Unify.trace_types		unify_trace_types
  3361   Simplifier.simp_depth_limit	simp_depth_limit
  3362   Blast.depth_limit		blast_depth_limit
  3363   DatatypeProp.dtK		datatype_distinctness_limit
  3364   fast_arith_neq_limit  	fast_arith_neq_limit
  3365   fast_arith_split_limit	fast_arith_split_limit
  3366 
  3367 * Named collections of theorems may be easily installed as context
  3368 data using the functor NamedThmsFun (see also
  3369 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3370 attributes; there is also a toplevel print command.  This facility is
  3371 just a common case of general context data, which is the preferred way
  3372 for anything more complex than just a list of facts in canonical
  3373 order.
  3374 
  3375 * Isar: command 'declaration' augments a local theory by generic
  3376 declaration functions written in ML.  This enables arbitrary content
  3377 being added to the context, depending on a morphism that tells the
  3378 difference of the original declaration context wrt. the application
  3379 context encountered later on.
  3380 
  3381 * Isar: proper interfaces for simplification procedures.  Command
  3382 'simproc_setup' declares named simprocs (with match patterns, and body
  3383 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3384 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3385 
  3386 * Isar: an extra pair of brackets around attribute declarations
  3387 abbreviates a theorem reference involving an internal dummy fact,
  3388 which will be ignored later --- only the effect of the attribute on
  3389 the background context will persist.  This form of in-place
  3390 declarations is particularly useful with commands like 'declare' and
  3391 'using', for example ``have A using [[simproc a]] by simp''.
  3392 
  3393 * Isar: method "assumption" (and implicit closing of subproofs) now
  3394 takes simple non-atomic goal assumptions into account: after applying
  3395 an assumption as a rule the resulting subgoals are solved by atomic
  3396 assumption steps.  This is particularly useful to finish 'obtain'
  3397 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3398 without referring to the original premise "!!x. P x ==> thesis" in the
  3399 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3400 more permissive.
  3401 
  3402 * Isar: implicit use of prems from the Isar proof context is
  3403 considered a legacy feature.  Common applications like ``have A .''
  3404 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3405 referencing facts explicitly here improves readability and
  3406 maintainability of proof texts.
  3407 
  3408 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3409 the obtained context from the course of reasoning!  For example:
  3410 
  3411   assume "EX x y. A x & B y"   -- "any previous fact"
  3412   then guess x and y by clarify
  3413 
  3414 This technique is potentially adventurous, depending on the facts and
  3415 proof tools being involved here.
  3416 
  3417 * Isar: known facts from the proof context may be specified as literal
  3418 propositions, using ASCII back-quote syntax.  This works wherever
  3419 named facts used to be allowed so far, in proof commands, proof
  3420 methods, attributes etc.  Literal facts are retrieved from the context
  3421 according to unification of type and term parameters.  For example,
  3422 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3423 theorems in the current context, then these are valid literal facts:
  3424 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3425 
  3426 There is also a proof method "fact" which does the same composition
  3427 for explicit goal states, e.g. the following proof texts coincide with
  3428 certain special cases of literal facts:
  3429 
  3430   have "A" by fact                 ==  note `A`
  3431   have "A ==> B" by fact           ==  note `A ==> B`
  3432   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3433   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3434 
  3435 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3436 outer syntax.  Thus symbolic identifiers may be used without
  3437 additional white space in declarations like this: ``assume *: A''.
  3438 
  3439 * Isar: 'print_facts' prints all local facts of the current context,
  3440 both named and unnamed ones.
  3441 
  3442 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3443 
  3444   def x == "t" and y == "u"
  3445 
  3446 * Isar: added command 'unfolding', which is structurally similar to
  3447 'using', but affects both the goal state and facts by unfolding given
  3448 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3449 'unfolded' attribute may be replaced by first-class proof text.
  3450 
  3451 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3452 and command 'unfolding' now all support object-level equalities
  3453 (potentially conditional).  The underlying notion of rewrite rule is
  3454 analogous to the 'rule_format' attribute, but *not* that of the
  3455 Simplifier (which is usually more generous).
  3456 
  3457 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3458 premises of a theorem by n. Useful in conjunction with drule.
  3459 
  3460 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3461 method expression within a sandbox consisting of the first N
  3462 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3463 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3464 simplifies all new goals that emerge from applying rule foo to the
  3465 originally first one.
  3466 
  3467 * Isar: schematic goals are no longer restricted to higher-order
  3468 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3469 expected.
  3470 
  3471 * Isar: the conclusion of a long theorem statement is now either
  3472 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3473 (essentially a disjunction of cases with local parameters and
  3474 assumptions).  The latter allows to express general elimination rules
  3475 adequately; in this notation common elimination rules look like this:
  3476 
  3477   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3478     assumes "EX x. P x"
  3479     obtains x where "P x"
  3480 
  3481   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3482     assumes "A & B"
  3483     obtains A and B
  3484 
  3485   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3486     assumes "A | B"
  3487     obtains
  3488       A
  3489     | B
  3490 
  3491 The subsequent classical rules even refer to the formal "thesis"
  3492 explicitly:
  3493 
  3494   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3495     obtains "~ thesis"
  3496 
  3497   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3498     obtains "thesis ==> something"
  3499 
  3500 The actual proof of an 'obtains' statement is analogous to that of the
  3501 Isar proof element 'obtain', only that there may be several cases.
  3502 Optional case names may be specified in parentheses; these will be
  3503 available both in the present proof and as annotations in the
  3504 resulting rule, for later use with the 'cases' method (cf. attribute
  3505 case_names).
  3506 
  3507 * Isar: the assumptions of a long theorem statement are available as
  3508 "assms" fact in the proof context.  This is more appropriate than the
  3509 (historical) "prems", which refers to all assumptions of the current
  3510 context, including those from the target locale, proof body etc.
  3511 
  3512 * Isar: 'print_statement' prints theorems from the current theory or
  3513 proof context in long statement form, according to the syntax of a
  3514 top-level lemma.
  3515 
  3516 * Isar: 'obtain' takes an optional case name for the local context
  3517 introduction rule (default "that").
  3518 
  3519 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3520 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3521 to occur.
  3522 
  3523 * Pure: syntax "CONST name" produces a fully internalized constant
  3524 according to the current context.  This is particularly useful for
  3525 syntax translations that should refer to internal constant
  3526 representations independently of name spaces.
  3527 
  3528 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3529 instead of "FOO ". This allows multiple binder declarations to coexist
  3530 in the same context.  INCOMPATIBILITY.
  3531 
  3532 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3533 primitive that also works in a locale context (both for constants and
  3534 fixed variables). Type declaration and internal syntactic representation
  3535 of given constants retrieved from the context. Likewise, the
  3536 'no_notation' command allows to remove given syntax annotations from the
  3537 current context.
  3538 
  3539 * Isar/locales: new derived specification elements 'axiomatization',
  3540 'definition', 'abbreviation', which support type-inference, admit
  3541 object-level specifications (equality, equivalence).  See also the
  3542 isar-ref manual.  Examples:
  3543 
  3544   axiomatization
  3545     eq  (infix "===" 50) where
  3546     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3547 
  3548   definition "f x y = x + y + 1"
  3549   definition g where "g x = f x x"
  3550 
  3551   abbreviation
  3552     neq  (infix "=!=" 50) where
  3553     "x =!= y == ~ (x === y)"
  3554 
  3555 These specifications may be also used in a locale context.  Then the
  3556 constants being introduced depend on certain fixed parameters, and the
  3557 constant name is qualified by the locale base name.  An internal
  3558 abbreviation takes care for convenient input and output, making the
  3559 parameters implicit and using the original short name.  See also
  3560 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3561 entities from a monomorphic theory.
  3562 
  3563 Presently, abbreviations are only available 'in' a target locale, but
  3564 not inherited by general import expressions.  Also note that
  3565 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3566 'translations' in common applications.  The "no_abbrevs" print mode
  3567 prevents folding of abbreviations in term output.
  3568 
  3569 Concrete syntax is attached to specified constants in internal form,
  3570 independently of name spaces.  The parse tree representation is
  3571 slightly different -- use 'notation' instead of raw 'syntax', and
  3572 'translations' with explicit "CONST" markup to accommodate this.
  3573 
  3574 * Pure/Isar: unified syntax for new-style specification mechanisms
  3575 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3576 full type inference and dummy patterns ("_").  For example:
  3577 
  3578   definition "K x _ = x"
  3579 
  3580   inductive conj for A B
  3581   where "A ==> B ==> conj A B"
  3582 
  3583 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3584 the current context.  Print mode "no_abbrevs" prevents inversion of
  3585 abbreviations on output.
  3586 
  3587 * Isar/locales: improved parameter handling: use of locales "var" and
  3588 "struct" no longer necessary; - parameter renamings are no longer
  3589 required to be injective.  For example, this allows to define
  3590 endomorphisms as locale endom = homom mult mult h.
  3591 
  3592 * Isar/locales: changed the way locales with predicates are defined.
  3593 Instead of accumulating the specification, the imported expression is
  3594 now an interpretation.  INCOMPATIBILITY: different normal form of
  3595 locale expressions.  In particular, in interpretations of locales with
  3596 predicates, goals repesenting already interpreted fragments are not
  3597 removed automatically.  Use methods `intro_locales' and
  3598 `unfold_locales'; see below.
  3599 
  3600 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3601 provide backward reasoning on locales predicates.  The methods are
  3602 aware of interpretations and discharge corresponding goals.
  3603 `intro_locales' is less aggressive then `unfold_locales' and does not
  3604 unfold predicates to assumptions.
  3605 
  3606 * Isar/locales: the order in which locale fragments are accumulated
  3607 has changed.  This enables to override declarations from fragments due
  3608 to interpretations -- for example, unwanted simp rules.
  3609 
  3610 * Isar/locales: interpretation in theories and proof contexts has been
  3611 extended.  One may now specify (and prove) equations, which are
  3612 unfolded in interpreted theorems.  This is useful for replacing
  3613 defined concepts (constants depending on locale parameters) by
  3614 concepts already existing in the target context.  Example:
  3615 
  3616   interpretation partial_order ["op <= :: [int, int] => bool"]
  3617     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3618 
  3619 Typically, the constant `partial_order.less' is created by a
  3620 definition specification element in the context of locale
  3621 partial_order.
  3622 
  3623 * Method "induct": improved internal context management to support
  3624 local fixes and defines on-the-fly. Thus explicit meta-level
  3625 connectives !!  and ==> are rarely required anymore in inductive goals
  3626 (using object-logic connectives for this purpose has been long
  3627 obsolete anyway). Common proof patterns are explained in
  3628 src/HOL/Induct/Common_Patterns.thy, see also
  3629 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3630 examples.
  3631 
  3632 * Method "induct": improved handling of simultaneous goals. Instead of
  3633 introducing object-level conjunction, the statement is now split into
  3634 several conclusions, while the corresponding symbolic cases are nested
  3635 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3636 see src/HOL/Induct/Common_Patterns.thy, for example.
  3637 
  3638 * Method "induct": mutual induction rules are now specified as a list
  3639 of rule sharing the same induction cases. HOL packages usually provide
  3640 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3641 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3642 mutual induction rules differently, i.e. like this:
  3643 
  3644   (induct rule: foo_bar.inducts)
  3645   (induct set: foo bar)
  3646   (induct pred: foo bar)
  3647   (induct type: foo bar)
  3648 
  3649 The ML function ProjectRule.projections turns old-style rules into the
  3650 new format.
  3651 
  3652 * Method "coinduct": dual of induction, see
  3653 src/HOL/Library/Coinductive_List.thy for various examples.
  3654 
  3655 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3656 considered a legacy feature.
  3657 
  3658 * Attribute "symmetric" produces result with standardized schematic
  3659 variables (index 0).  Potential INCOMPATIBILITY.
  3660 
  3661 * Simplifier: by default the simplifier trace only shows top level
  3662 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3663 default. Thus there is less danger of being flooded by the trace. The
  3664 trace indicates where parts have been suppressed.
  3665   
  3666 * Provers/classical: removed obsolete classical version of elim_format
  3667 attribute; classical elim/dest rules are now treated uniformly when
  3668 manipulating the claset.
  3669 
  3670 * Provers/classical: stricter checks to ensure that supplied intro,
  3671 dest and elim rules are well-formed; dest and elim rules must have at
  3672 least one premise.
  3673 
  3674 * Provers/classical: attributes dest/elim/intro take an optional
  3675 weight argument for the rule (just as the Pure versions).  Weights are
  3676 ignored by automated tools, but determine the search order of single
  3677 rule steps.
  3678 
  3679 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3680 where the body does not mention the bound variable.  Note that dummy
  3681 patterns implicitly depend on their context of bounds, which makes
  3682 "{_. _}" match any set comprehension as expected.  Potential
  3683 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3684 constant "_idtdummy" in the binding position.
  3685 
  3686 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3687 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3688 for example "A -> B" => "Pi A (%_. B)".
  3689 
  3690 * Pure: 'class_deps' command visualizes the subclass relation, using
  3691 the graph browser tool.
  3692 
  3693 * Pure: 'print_theory' now suppresses certain internal declarations by
  3694 default; use '!' option for full details.
  3695 
  3696 
  3697 *** HOL ***
  3698 
  3699 * Method "metis" proves goals by applying the Metis general-purpose
  3700 resolution prover (see also http://gilith.com/software/metis/).
  3701 Examples are in the directory MetisExamples.  WARNING: the
  3702 Isabelle/HOL-Metis integration does not yet work properly with
  3703 multi-threading.
  3704   
  3705 * Command 'sledgehammer' invokes external automatic theorem provers as
  3706 background processes.  It generates calls to the "metis" method if
  3707 successful. These can be pasted into the proof.  Users do not have to
  3708 wait for the automatic provers to return.  WARNING: does not really
  3709 work with multi-threading.
  3710 
  3711 * New "auto_quickcheck" feature tests outermost goal statements for
  3712 potential counter-examples.  Controlled by ML references
  3713 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3714 5000 milliseconds).  Fails silently if statements is outside of
  3715 executable fragment, or any other codgenerator problem occurs.
  3716 
  3717 * New constant "undefined" with axiom "undefined x = undefined".
  3718 
  3719 * Added class "HOL.eq", allowing for code generation with polymorphic
  3720 equality.
  3721 
  3722 * Some renaming of class constants due to canonical name prefixing in
  3723 the new 'class' package:
  3724 
  3725     HOL.abs ~> HOL.abs_class.abs
  3726     HOL.divide ~> HOL.divide_class.divide
  3727     0 ~> HOL.zero_class.zero
  3728     1 ~> HOL.one_class.one
  3729     op + ~> HOL.plus_class.plus
  3730     op - ~> HOL.minus_class.minus
  3731     uminus ~> HOL.minus_class.uminus
  3732     op * ~> HOL.times_class.times
  3733     op < ~> HOL.ord_class.less
  3734     op <= > HOL.ord_class.less_eq
  3735     Nat.power ~> Power.power_class.power
  3736     Nat.size ~> Nat.size_class.size
  3737     Numeral.number_of ~> Numeral.number_class.number_of
  3738     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3739     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3740     Orderings.min ~> Orderings.ord_class.min
  3741     Orderings.max ~> Orderings.ord_class.max
  3742     Divides.op div ~> Divides.div_class.div
  3743     Divides.op mod ~> Divides.div_class.mod
  3744     Divides.op dvd ~> Divides.div_class.dvd
  3745 
  3746 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3747 
  3748 a) User-defined constants using any of the names "plus", "minus",
  3749 "times", "less" or "less_eq". The standard syntax translations for
  3750 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3751 names.
  3752 
  3753 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3754 INCOMPATIBILITY: use more specific names.
  3755 
  3756 c) Permutative equations (e.g. "a + b = b + a")
  3757 Since the change of names also changes the order of terms, permutative
  3758 rewrite rules may get applied in a different order. Experience shows
  3759 that this is rarely the case (only two adaptions in the whole Isabelle
  3760 distribution).  INCOMPATIBILITY: rewrite proofs
  3761 
  3762 d) ML code directly refering to constant names
  3763 This in general only affects hand-written proof tactics, simprocs and
  3764 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3765 Consider using @{const_name} antiquotation.
  3766 
  3767 * New class "default" with associated constant "default".
  3768 
  3769 * Function "sgn" is now overloaded and available on int, real, complex
  3770 (and other numeric types), using class "sgn".  Two possible defs of
  3771 sgn are given as equational assumptions in the classes sgn_if and
  3772 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3773 INCOMPATIBILITY.
  3774 
  3775 * Locale "partial_order" now unified with class "order" (cf. theory
  3776 Orderings), added parameter "less".  INCOMPATIBILITY.
  3777 
  3778 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3779 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3780 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3781 
  3782 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3783 changed order of proof goals in instance proofs.
  3784 
  3785 * The transitivity reasoner for partial and linear orders is set up
  3786 for classes "order" and "linorder".  Instances of the reasoner are available
  3787 in all contexts importing or interpreting the corresponding locales.
  3788 Method "order" invokes the reasoner separately; the reasoner
  3789 is also integrated with the Simplifier as a solver.  Diagnostic
  3790 command 'print_orders' shows the available instances of the reasoner
  3791 in the current context.
  3792 
  3793 * Localized monotonicity predicate in theory "Orderings"; integrated
  3794 lemmas max_of_mono and min_of_mono with this predicate.
  3795 INCOMPATIBILITY.
  3796 
  3797 * Formulation of theorem "dense" changed slightly due to integration
  3798 with new class dense_linear_order.
  3799 
  3800 * Uniform lattice theory development in HOL.
  3801 
  3802     constants "meet" and "join" now named "inf" and "sup"
  3803     constant "Meet" now named "Inf"
  3804 
  3805     classes "meet_semilorder" and "join_semilorder" now named
  3806       "lower_semilattice" and "upper_semilattice"
  3807     class "lorder" now named "lattice"
  3808     class "comp_lat" now named "complete_lattice"
  3809 
  3810     Instantiation of lattice classes allows explicit definitions
  3811     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3812 
  3813   INCOMPATIBILITY.  Theorem renames:
  3814 
  3815     meet_left_le            ~> inf_le1
  3816     meet_right_le           ~> inf_le2
  3817     join_left_le            ~> sup_ge1
  3818     join_right_le           ~> sup_ge2
  3819     meet_join_le            ~> inf_sup_ord
  3820     le_meetI                ~> le_infI
  3821     join_leI                ~> le_supI
  3822     le_meet                 ~> le_inf_iff
  3823     le_join                 ~> ge_sup_conv
  3824     meet_idempotent         ~> inf_idem
  3825     join_idempotent         ~> sup_idem
  3826     meet_comm               ~> inf_commute
  3827     join_comm               ~> sup_commute
  3828     meet_leI1               ~> le_infI1
  3829     meet_leI2               ~> le_infI2
  3830     le_joinI1               ~> le_supI1
  3831     le_joinI2               ~> le_supI2
  3832     meet_assoc              ~> inf_assoc
  3833     join_assoc              ~> sup_assoc
  3834     meet_left_comm          ~> inf_left_commute
  3835     meet_left_idempotent    ~> inf_left_idem
  3836     join_left_comm          ~> sup_left_commute
  3837     join_left_idempotent    ~> sup_left_idem
  3838     meet_aci                ~> inf_aci
  3839     join_aci                ~> sup_aci
  3840     le_def_meet             ~> le_iff_inf
  3841     le_def_join             ~> le_iff_sup
  3842     join_absorp2            ~> sup_absorb2
  3843     join_absorp1            ~> sup_absorb1
  3844     meet_absorp1            ~> inf_absorb1
  3845     meet_absorp2            ~> inf_absorb2
  3846     meet_join_absorp        ~> inf_sup_absorb
  3847     join_meet_absorp        ~> sup_inf_absorb
  3848     distrib_join_le         ~> distrib_sup_le
  3849     distrib_meet_le         ~> distrib_inf_le
  3850 
  3851     add_meet_distrib_left   ~> add_inf_distrib_left
  3852     add_join_distrib_left   ~> add_sup_distrib_left
  3853     is_join_neg_meet        ~> is_join_neg_inf
  3854     is_meet_neg_join        ~> is_meet_neg_sup
  3855     add_meet_distrib_right  ~> add_inf_distrib_right
  3856     add_join_distrib_right  ~> add_sup_distrib_right
  3857     add_meet_join_distribs  ~> add_sup_inf_distribs
  3858     join_eq_neg_meet        ~> sup_eq_neg_inf
  3859     meet_eq_neg_join        ~> inf_eq_neg_sup
  3860     add_eq_meet_join        ~> add_eq_inf_sup
  3861     meet_0_imp_0            ~> inf_0_imp_0
  3862     join_0_imp_0            ~> sup_0_imp_0
  3863     meet_0_eq_0             ~> inf_0_eq_0
  3864     join_0_eq_0             ~> sup_0_eq_0
  3865     neg_meet_eq_join        ~> neg_inf_eq_sup
  3866     neg_join_eq_meet        ~> neg_sup_eq_inf
  3867     join_eq_if              ~> sup_eq_if
  3868 
  3869     mono_meet               ~> mono_inf
  3870     mono_join               ~> mono_sup
  3871     meet_bool_eq            ~> inf_bool_eq
  3872     join_bool_eq            ~> sup_bool_eq
  3873     meet_fun_eq             ~> inf_fun_eq
  3874     join_fun_eq             ~> sup_fun_eq
  3875     meet_set_eq             ~> inf_set_eq
  3876     join_set_eq             ~> sup_set_eq
  3877     meet1_iff               ~> inf1_iff
  3878     meet2_iff               ~> inf2_iff
  3879     meet1I                  ~> inf1I
  3880     meet2I                  ~> inf2I
  3881     meet1D1                 ~> inf1D1
  3882     meet2D1                 ~> inf2D1
  3883     meet1D2                 ~> inf1D2
  3884     meet2D2                 ~> inf2D2
  3885     meet1E                  ~> inf1E
  3886     meet2E                  ~> inf2E
  3887     join1_iff               ~> sup1_iff
  3888     join2_iff               ~> sup2_iff
  3889     join1I1                 ~> sup1I1
  3890     join2I1                 ~> sup2I1
  3891     join1I1                 ~> sup1I1
  3892     join2I2                 ~> sup1I2
  3893     join1CI                 ~> sup1CI
  3894     join2CI                 ~> sup2CI
  3895     join1E                  ~> sup1E
  3896     join2E                  ~> sup2E
  3897 
  3898     is_meet_Meet            ~> is_meet_Inf
  3899     Meet_bool_def           ~> Inf_bool_def
  3900     Meet_fun_def            ~> Inf_fun_def
  3901     Meet_greatest           ~> Inf_greatest
  3902     Meet_lower              ~> Inf_lower
  3903     Meet_set_def            ~> Inf_set_def
  3904 
  3905     Sup_def                 ~> Sup_Inf
  3906     Sup_bool_eq             ~> Sup_bool_def
  3907     Sup_fun_eq              ~> Sup_fun_def
  3908     Sup_set_eq              ~> Sup_set_def
  3909 
  3910     listsp_meetI            ~> listsp_infI
  3911     listsp_meet_eq          ~> listsp_inf_eq
  3912 
  3913     meet_min                ~> inf_min
  3914     join_max                ~> sup_max
  3915 
  3916 * Added syntactic class "size"; overloaded constant "size" now has
  3917 type "'a::size ==> bool"
  3918 
  3919 * Internal reorganisation of `size' of datatypes: size theorems
  3920 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3921 simplification rules by default!); theorems "prod.size" now named
  3922 "*.size".
  3923 
  3924 * Class "div" now inherits from class "times" rather than "type".
  3925 INCOMPATIBILITY.
  3926 
  3927 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  3928 Linorder etc.  have disappeared; operations defined in terms of
  3929 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  3930 
  3931 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  3932 
  3933 * HOL-Word: New extensive library and type for generic, fixed size
  3934 machine words, with arithemtic, bit-wise, shifting and rotating
  3935 operations, reflection into int, nat, and bool lists, automation for
  3936 linear arithmetic (by automatic reflection into nat or int), including
  3937 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  3938 arithmetic type classes, supporting automatic simplification of
  3939 numerals on all operations.
  3940 
  3941 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  3942 
  3943 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  3944 
  3945 * Code generator library theories:
  3946   - Code_Integer represents HOL integers by big integer literals in target
  3947     languages.
  3948   - Code_Char represents HOL characters by character literals in target
  3949     languages.
  3950   - Code_Char_chr like Code_Char, but also offers treatment of character
  3951     codes; includes Code_Integer.
  3952   - Executable_Set allows to generate code for finite sets using lists.
  3953   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  3954     denominator).
  3955   - Executable_Real implements a subset of real numbers, namly those
  3956     representable by rational numbers.
  3957   - Efficient_Nat implements natural numbers by integers, which in general will
  3958     result in higher efficency; pattern matching with 0/Suc is eliminated;
  3959     includes Code_Integer.
  3960   - Code_Index provides an additional datatype index which is mapped to
  3961     target-language built-in integers.
  3962   - Code_Message provides an additional datatype message_string which is isomorphic to
  3963     strings; messages are mapped to target-language strings.
  3964 
  3965 * New package for inductive predicates
  3966 
  3967   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  3968 
  3969     inductive
  3970       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3971       for z_1 :: U_1 and ... and z_n :: U_m
  3972     where
  3973       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3974     | ...
  3975 
  3976   with full support for type-inference, rather than
  3977 
  3978     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3979 
  3980     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3981     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3982 
  3983     inductive "s z_1 ... z_m"
  3984     intros
  3985       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3986       ...
  3987 
  3988   For backward compatibility, there is a wrapper allowing inductive
  3989   sets to be defined with the new package via
  3990 
  3991     inductive_set
  3992       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3993       for z_1 :: U_1 and ... and z_n :: U_m
  3994     where
  3995       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3996     | ...
  3997 
  3998   or
  3999 
  4000     inductive_set
  4001       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4002       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4003       for z_1 :: U_1 and ... and z_n :: U_m
  4004     where
  4005       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4006     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4007     | ...
  4008 
  4009   if the additional syntax "p ..." is required.
  4010 
  4011   Numerous examples can be found in the subdirectories src/HOL/Auth,
  4012   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  4013 
  4014   INCOMPATIBILITIES:
  4015 
  4016   - Since declaration and definition of inductive sets or predicates
  4017     is no longer separated, abbreviations involving the newly
  4018     introduced sets or predicates must be specified together with the
  4019     introduction rules after the 'where' keyword (see above), rather
  4020     than before the actual inductive definition.
  4021 
  4022   - The variables in induction and elimination rules are now
  4023     quantified in the order of their occurrence in the introduction
  4024     rules, rather than in alphabetical order. Since this may break
  4025     some proofs, these proofs either have to be repaired, e.g. by
  4026     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  4027     statements of the form
  4028 
  4029       case (rule_i a_i_1 ... a_i_{k_i})
  4030 
  4031     or the old order of quantification has to be restored by explicitly adding
  4032     meta-level quantifiers in the introduction rules, i.e.
  4033 
  4034       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  4035 
  4036   - The format of the elimination rules is now
  4037 
  4038       p z_1 ... z_m x_1 ... x_n ==>
  4039         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4040         ==> ... ==> P
  4041 
  4042     for predicates and
  4043 
  4044       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4045         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4046         ==> ... ==> P
  4047 
  4048     for sets rather than
  4049 
  4050       x : s z_1 ... z_m ==>
  4051         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4052         ==> ... ==> P
  4053 
  4054     This may require terms in goals to be expanded to n-tuples
  4055     (e.g. using case_tac or simplification with the split_paired_all
  4056     rule) before the above elimination rule is applicable.
  4057 
  4058   - The elimination or case analysis rules for (mutually) inductive
  4059     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4060     list of rules "p_1_..._p_k.elims" is no longer available.
  4061 
  4062 * New package "function"/"fun" for general recursive functions,
  4063 supporting mutual and nested recursion, definitions in local contexts,
  4064 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4065 for small examples, and the separate tutorial on the function
  4066 package. The old recdef "package" is still available as before, but
  4067 users are encouraged to use the new package.
  4068 
  4069 * Method "lexicographic_order" automatically synthesizes termination
  4070 relations as lexicographic combinations of size measures. 
  4071 
  4072 * Case-expressions allow arbitrary constructor-patterns (including
  4073 "_") and take their order into account, like in functional
  4074 programming.  Internally, this is translated into nested
  4075 case-expressions; missing cases are added and mapped to the predefined
  4076 constant "undefined". In complicated cases printing may no longer show
  4077 the original input but the internal form. Lambda-abstractions allow
  4078 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4079 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4080 variable.
  4081 
  4082 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4083 is an abbreviation for "of_nat :: nat => int". The simplification
  4084 rules for "of_nat" have been changed to work like "int" did
  4085 previously.  Potential INCOMPATIBILITY:
  4086   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4087   - of_nat_diff and of_nat_mult are no longer default simp rules
  4088 
  4089 * Method "algebra" solves polynomial equations over (semi)rings using
  4090 Groebner bases. The (semi)ring structure is defined by locales and the
  4091 tool setup depends on that generic context. Installing the method for
  4092 a specific type involves instantiating the locale and possibly adding
  4093 declarations for computation on the coefficients.  The method is
  4094 already instantiated for natural numbers and for the axiomatic class
  4095 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4096 CALCULEMUS 2007 for the general principles underlying this
  4097 architecture of context-aware proof-tools.
  4098 
  4099 * Method "ferrack" implements quantifier elimination over
  4100 special-purpose dense linear orders using locales (analogous to
  4101 "algebra"). The method is already installed for class
  4102 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4103 rat, etc.
  4104 
  4105 * Former constant "List.op @" now named "List.append".  Use ML
  4106 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4107 circumvent possible incompatibilities when working on ML level.
  4108 
  4109 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4110 
  4111 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4112 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4113 
  4114 * New syntax for Haskell-like list comprehension (input only), eg.
  4115 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4116 
  4117 * The special syntax for function "filter" has changed from [x :
  4118 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4119 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4120 
  4121 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4122 defined on nat only, as an abbreviation for [a..<Suc b]
  4123 INCOMPATIBILITY.
  4124 
  4125 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4126 
  4127 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4128 
  4129 * New lemma collection field_simps (an extension of ring_simps) for
  4130 manipulating (in)equations involving division. Multiplies with all
  4131 denominators that can be proved to be non-zero (in equations) or
  4132 positive/negative (in inequations).
  4133 
  4134 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4135 have been improved and renamed to ring_simps, group_simps and
  4136 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4137 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4138 
  4139 * Theory Library/Commutative_Ring: switched from recdef to function
  4140 package; constants add, mul, pow now curried.  Infix syntax for
  4141 algebraic operations.
  4142 
  4143 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4144 INCOMPATIBILITY.
  4145 
  4146 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4147 INCOMPATIBILITY.
  4148 
  4149 * HOL/records: generalised field-update to take a function on the
  4150 field rather than the new value: r(|A := x|) is translated to A_update
  4151 (K x) r The K-combinator that is internally used is called K_record.
  4152 INCOMPATIBILITY: Usage of the plain update functions has to be
  4153 adapted.
  4154  
  4155 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4156 * x = 0, which are required for a semiring.  Richer structures do not
  4157 inherit from semiring_0 anymore, because this property is a theorem
  4158 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4159 there is more to prove, but this is mostly trivial.
  4160 
  4161 * Class "recpower" is generalized to arbitrary monoids, not just
  4162 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4163 commutativity or semiring properties additionally.
  4164 
  4165 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4166 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4167 better use 'abbreviation'.
  4168 
  4169 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4170 
  4171 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4172 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4173 significant changes for setting up numeral syntax for types:
  4174   - New constants Numeral.pred and Numeral.succ instead
  4175       of former Numeral.bin_pred and Numeral.bin_succ.
  4176   - Use integer operations instead of bin_add, bin_mult and so on.
  4177   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4178   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4179 
  4180 See src/HOL/Integ/IntArith.thy for an example setup.
  4181 
  4182 * Command 'normal_form' computes the normal form of a term that may
  4183 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4184 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4185 heavy-duty computations because the functions are compiled to ML
  4186 first.  Correspondingly, a method "normalization" is provided.  See
  4187 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4188 
  4189 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4190 25 like -->); output depends on the "iff" print_mode, the default is
  4191 "A = B" (with priority 50).
  4192 
  4193 * Relations less (<) and less_eq (<=) are also available on type bool.
  4194 Modified syntax to disallow nesting without explicit parentheses,
  4195 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4196 INCOMPATIBILITY.
  4197 
  4198 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4199 
  4200 * Relation composition operator "op O" now has precedence 75 and binds
  4201 stronger than union and intersection. INCOMPATIBILITY.
  4202 
  4203 * The old set interval syntax "{m..n(}" (and relatives) has been
  4204 removed.  Use "{m..<n}" (and relatives) instead.
  4205 
  4206 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4207 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4208 ``declare [[simproc del: neq]]''.
  4209 
  4210 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4211 True/False.
  4212 
  4213 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4214 
  4215 * Theorem setsum_mult renamed to setsum_right_distrib.
  4216 
  4217 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4218 ``rule'' method.
  4219 
  4220 * Reimplemented methods "sat" and "satx", with several improvements:
  4221 goals no longer need to be stated as "<prems> ==> False", equivalences
  4222 (i.e. "=" on type bool) are handled, variable names of the form
  4223 "lit_<n>" are no longer reserved, significant speedup.
  4224 
  4225 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4226 zChaff is still supported as well.
  4227 
  4228 * 'inductive' and 'datatype': provide projections of mutual rules,
  4229 bundled as foo_bar.inducts;
  4230 
  4231 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4232 Library.
  4233 
  4234 * Library: moved theory Accessible_Part to main HOL.
  4235 
  4236 * Library: added theory Coinductive_List of potentially infinite lists
  4237 as greatest fixed-point.
  4238 
  4239 * Library: added theory AssocList which implements (finite) maps as
  4240 association lists.
  4241 
  4242 * Method "evaluation" solves goals (i.e. a boolean expression)
  4243 efficiently by compiling it to ML.  The goal is "proved" (via an
  4244 oracle) if it evaluates to True.
  4245 
  4246 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4247 also when invoked by the simplifier.  This results in the Simplifier
  4248 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4249 Configuration option fast_arith_split_limit=0 recovers the old
  4250 behavior.
  4251 
  4252 * Support for hex (0x20) and binary (0b1001) numerals.
  4253 
  4254 * New method: reify eqs (t), where eqs are equations for an
  4255 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4256 parameter, computes a term s::'b and a list xs::'a list and proves the
  4257 theorem I xs s = t. This is also known as reification or quoting. The
  4258 resulting theorem is applied to the subgoal to substitute t with I xs
  4259 s.  If t is omitted, the subgoal itself is reified.
  4260 
  4261 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4262 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4263 where f is supposed to be a computable function (in the sense of code
  4264 generattion). The method uses reify to compute s and xs as above then
  4265 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4266 r and finally gets the theorem t = r, which is again applied to the
  4267 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4268 
  4269 * Reflection: Automatic reification now handels binding, an example is
  4270 available in src/HOL/ex/ReflectionEx.thy
  4271 
  4272 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4273 command 'statespace' that is similar to 'record', but introduces an
  4274 abstract specification based on the locale infrastructure instead of
  4275 HOL types.  This leads to extra flexibility in composing state spaces,
  4276 in particular multiple inheritance and renaming of components.
  4277 
  4278 
  4279 *** HOL-Complex ***
  4280 
  4281 * Hyperreal: Functions root and sqrt are now defined on negative real
  4282 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4283 Nonnegativity side conditions have been removed from many lemmas, so
  4284 that more subgoals may now be solved by simplification; potential
  4285 INCOMPATIBILITY.
  4286 
  4287 * Real: new type classes formalize real normed vector spaces and
  4288 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4289 and norm :: 'a => real.
  4290 
  4291 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4292 reals into other types. The overloaded constant Reals :: 'a set is now
  4293 defined as range of_real; potential INCOMPATIBILITY.
  4294 
  4295 * Real: proper support for ML code generation, including 'quickcheck'.
  4296 Reals are implemented as arbitrary precision rationals.
  4297 
  4298 * Hyperreal: Several constants that previously worked only for the
  4299 reals have been generalized, so they now work over arbitrary vector
  4300 spaces. Type annotations may need to be added in some cases; potential
  4301 INCOMPATIBILITY.
  4302 
  4303   Infinitesimal  :: ('a::real_normed_vector) star set
  4304   HFinite        :: ('a::real_normed_vector) star set
  4305   HInfinite      :: ('a::real_normed_vector) star set
  4306   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4307   monad          :: ('a::real_normed_vector) star => 'a star set
  4308   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4309   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4310   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4311   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4312   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4313   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4314   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4315   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4316   sgn            :: 'a::real_normed_vector => 'a
  4317   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4318 
  4319 * Complex: Some complex-specific constants are now abbreviations for
  4320 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4321 hnorm.  Other constants have been entirely removed in favor of the
  4322 polymorphic versions (INCOMPATIBILITY):
  4323 
  4324   approx        <-- capprox
  4325   HFinite       <-- CFinite
  4326   HInfinite     <-- CInfinite
  4327   Infinitesimal <-- CInfinitesimal
  4328   monad         <-- cmonad
  4329   galaxy        <-- cgalaxy
  4330   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4331   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4332   (ns)deriv     <-- (ns)cderiv
  4333 
  4334 
  4335 *** HOL-Algebra ***
  4336 
  4337 * Formalisation of ideals and the quotient construction over rings.
  4338 
  4339 * Order and lattice theory no longer based on records.
  4340 INCOMPATIBILITY.
  4341 
  4342 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4343 greatest_closed.  INCOMPATIBILITY.
  4344 
  4345 * Method algebra is now set up via an attribute.  For examples see
  4346 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4347 of algebraic structures.
  4348 
  4349 * Renamed theory CRing to Ring.
  4350 
  4351 
  4352 *** HOL-Nominal ***
  4353 
  4354 * Substantial, yet incomplete support for nominal datatypes (binding
  4355 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4356 src/HOL/Nominal/Examples.  Prospective users should consult
  4357 http://isabelle.in.tum.de/nominal/
  4358 
  4359 
  4360 *** ML ***
  4361 
  4362 * ML basics: just one true type int, which coincides with IntInf.int
  4363 (even on SML/NJ).
  4364 
  4365 * ML within Isar: antiquotations allow to embed statically-checked
  4366 formal entities in the source, referring to the context available at
  4367 compile-time.  For example:
  4368 
  4369 ML {* @{sort "{zero,one}"} *}
  4370 ML {* @{typ "'a => 'b"} *}
  4371 ML {* @{term "%x. x"} *}
  4372 ML {* @{prop "x == y"} *}
  4373 ML {* @{ctyp "'a => 'b"} *}
  4374 ML {* @{cterm "%x. x"} *}
  4375 ML {* @{cprop "x == y"} *}
  4376 ML {* @{thm asm_rl} *}
  4377 ML {* @{thms asm_rl} *}
  4378 ML {* @{type_name c} *}
  4379 ML {* @{type_syntax c} *}
  4380 ML {* @{const_name c} *}
  4381 ML {* @{const_syntax c} *}
  4382 ML {* @{context} *}
  4383 ML {* @{theory} *}
  4384 ML {* @{theory Pure} *}
  4385 ML {* @{theory_ref} *}
  4386 ML {* @{theory_ref Pure} *}
  4387 ML {* @{simpset} *}
  4388 ML {* @{claset} *}
  4389 ML {* @{clasimpset} *}
  4390 
  4391 The same works for sources being ``used'' within an Isar context.
  4392 
  4393 * ML in Isar: improved error reporting; extra verbosity with
  4394 ML_Context.trace enabled.
  4395 
  4396 * Pure/General/table.ML: the join operations now works via exceptions
  4397 DUP/SAME instead of type option. This is simpler in simple cases, and
  4398 admits slightly more efficient complex applications.
  4399 
  4400 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4401 use Context.generic instead of just theory.
  4402 
  4403 * Pure: datatype Context.generic joins theory/Proof.context and
  4404 provides some facilities for code that works in either kind of
  4405 context, notably GenericDataFun for uniform theory and proof data.
  4406 
  4407 * Pure: simplified internal attribute type, which is now always
  4408 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4409 local (Proof.context) attributes have been discontinued, while
  4410 minimizing code duplication. Thm.rule_attribute and
  4411 Thm.declaration_attribute build canonical attributes; see also structure
  4412 Context for further operations on Context.generic, notably
  4413 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4414 declarations and definitions.
  4415 
  4416 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4417 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4418 init only required for impure data. INCOMPATIBILITY: empty really need
  4419 to be empty (no dependencies on theory content!)
  4420 
  4421 * Pure/kernel: consts certification ignores sort constraints given in
  4422 signature declarations. (This information is not relevant to the
  4423 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4424 potential INCOMPATIBILITY.
  4425 
  4426 * Pure: axiomatic type classes are now purely definitional, with
  4427 explicit proofs of class axioms and super class relations performed
  4428 internally. See Pure/axclass.ML for the main internal interfaces --
  4429 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4430 AxClass.axiomatize_class/classrel/arity supersede
  4431 Sign.add_classes/classrel/arities.
  4432 
  4433 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4434 global/local versions on theory vs. Proof.context have been
  4435 discontinued; Attrib.syntax and Method.syntax have been adapted
  4436 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4437 attributes, methods, etc.
  4438 
  4439 * Pure: several functions of signature "... -> theory -> theory * ..."
  4440 have been reoriented to "... -> theory -> ... * theory" in order to
  4441 allow natural usage in combination with the ||>, ||>>, |-> and
  4442 fold_map combinators.
  4443 
  4444 * Pure: official theorem names (closed derivations) and additional
  4445 comments (tags) are now strictly separate.  Name hints -- which are
  4446 maintained as tags -- may be attached any time without affecting the
  4447 derivation.
  4448 
  4449 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4450 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4451 achieve the old behaviour.
  4452 
  4453 * Pure: the "Goal" constant is now called "prop", supporting a
  4454 slightly more general idea of ``protecting'' meta-level rule
  4455 statements.
  4456 
  4457 * Pure: Logic.(un)varify only works in a global context, which is now
  4458 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4459 Logic.legacy_(un)varify as temporary workaround.
  4460 
  4461 * Pure: structure Name provides scalable operations for generating
  4462 internal variable names, notably Name.variants etc.  This replaces
  4463 some popular functions from term.ML:
  4464 
  4465   Term.variant		->  Name.variant
  4466   Term.variantlist	->  Name.variant_list
  4467   Term.invent_names	->  Name.invent_list
  4468 
  4469 Note that low-level renaming rarely occurs in new code -- operations
  4470 from structure Variable are used instead (see below).
  4471 
  4472 * Pure: structure Variable provides fundamental operations for proper
  4473 treatment of fixed/schematic variables in a context.  For example,
  4474 Variable.import introduces fixes for schematics of given facts and
  4475 Variable.export reverses the effect (up to renaming) -- this replaces
  4476 various freeze_thaw operations.
  4477 
  4478 * Pure: structure Goal provides simple interfaces for
  4479 init/conclude/finish and tactical prove operations (replacing former
  4480 Tactic.prove).  Goal.prove is the canonical way to prove results
  4481 within a given context; Goal.prove_global is a degraded version for
  4482 theory level goals, including a global Drule.standard.  Note that
  4483 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4484 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4485 in a locale context).
  4486 
  4487 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4488 and type checking (Syntax.check_term etc.), with common combinations
  4489 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4490 which are considered legacy and await removal.
  4491 
  4492 * Pure/Syntax: generic interfaces for type unchecking
  4493 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4494 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4495 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4496 available for convenience, but refer to the very same operations using
  4497 a mere theory instead of a full context.
  4498 
  4499 * Isar: simplified treatment of user-level errors, using exception
  4500 ERROR of string uniformly.  Function error now merely raises ERROR,
  4501 without any side effect on output channels.  The Isar toplevel takes
  4502 care of proper display of ERROR exceptions.  ML code may use plain
  4503 handle/can/try; cat_error may be used to concatenate errors like this:
  4504 
  4505   ... handle ERROR msg => cat_error msg "..."
  4506 
  4507 Toplevel ML code (run directly or through the Isar toplevel) may be
  4508 embedded into the Isar toplevel with exception display/debug like
  4509 this:
  4510 
  4511   Isar.toplevel (fn () => ...)
  4512 
  4513 INCOMPATIBILITY, removed special transform_error facilities, removed
  4514 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4515 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4516 -- use plain ERROR instead.
  4517 
  4518 * Isar: theory setup now has type (theory -> theory), instead of a
  4519 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4520 
  4521 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4522 ProofContext.debug/verbose flags.
  4523 
  4524 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4525 theory before entering a proof state.  Transactions now always see a
  4526 quasi-functional intermediate checkpoint, both in interactive and
  4527 batch mode.
  4528 
  4529 * Isar: simplified interfaces for outer syntax.  Renamed
  4530 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4531 OuterSyntax.add_parsers -- this functionality is now included in
  4532 OuterSyntax.command etc.  INCOMPATIBILITY.
  4533 
  4534 * Simplifier: the simpset of a running simplification process now
  4535 contains a proof context (cf. Simplifier.the_context), which is the
  4536 very context that the initial simpset has been retrieved from (by
  4537 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4538 (solver, looper etc.) may depend on arbitrary proof data.
  4539 
  4540 * Simplifier.inherit_context inherits the proof context (plus the
  4541 local bounds) of the current simplification process; any simproc
  4542 etc. that calls the Simplifier recursively should do this!  Removed
  4543 former Simplifier.inherit_bounds, which is already included here --
  4544 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4545 specify an explicit context using Simplifier.context/theory_context.
  4546 
  4547 * Simplifier/Classical Reasoner: more abstract interfaces
  4548 change_simpset/claset for modifying the simpset/claset reference of a
  4549 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4550 INCOMPATIBILITY.
  4551 
  4552 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4553 "Trueprop" etc.
  4554 
  4555 
  4556 *** System ***
  4557 
  4558 * settings: the default heap location within ISABELLE_HOME_USER now
  4559 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4560 Isabelle installations.
  4561 
  4562 * isabelle-process: option -S (secure mode) disables some critical
  4563 operations, notably runtime compilation and evaluation of ML source
  4564 code.
  4565 
  4566 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4567 
  4568 * Support for parallel execution, using native multicore support of
  4569 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4570 independent theories, according to the given theory header
  4571 specifications. The maximum number of worker threads is specified via
  4572 usedir option -M or the "max-threads" setting in Proof General. A
  4573 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4574 to 6 on a 8-core machine.  User-code needs to observe certain
  4575 guidelines for thread-safe programming, see appendix A in the Isar
  4576 Implementation manual.
  4577 
  4578 
  4579 
  4580 New in Isabelle2005 (October 2005)
  4581 ----------------------------------
  4582 
  4583 *** General ***
  4584 
  4585 * Theory headers: the new header syntax for Isar theories is
  4586 
  4587   theory <name>
  4588   imports <theory1> ... <theoryN>
  4589   uses <file1> ... <fileM>
  4590   begin
  4591 
  4592 where the 'uses' part is optional.  The previous syntax
  4593 
  4594   theory <name> = <theory1> + ... + <theoryN>:
  4595 
  4596 will disappear in the next release.  Use isatool fixheaders to convert
  4597 existing theory files.  Note that there is no change in ancient
  4598 non-Isar theories now, but these will disappear soon.
  4599 
  4600 * Theory loader: parent theories can now also be referred to via
  4601 relative and absolute paths.
  4602 
  4603 * Command 'find_theorems' searches for a list of criteria instead of a
  4604 list of constants. Known criteria are: intro, elim, dest, name:string,
  4605 simp:term, and any term. Criteria can be preceded by '-' to select
  4606 theorems that do not match. Intro, elim, dest select theorems that
  4607 match the current goal, name:s selects theorems whose fully qualified
  4608 name contain s, and simp:term selects all simplification rules whose
  4609 lhs match term.  Any other term is interpreted as pattern and selects
  4610 all theorems matching the pattern. Available in ProofGeneral under
  4611 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4612 
  4613   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4614 
  4615 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4616 matching the current goal as introduction rule and not having "HOL."
  4617 in their name (i.e. not being defined in theory HOL).
  4618 
  4619 * Command 'thms_containing' has been discontinued in favour of
  4620 'find_theorems'; INCOMPATIBILITY.
  4621 
  4622 * Communication with Proof General is now 8bit clean, which means that
  4623 Unicode text in UTF-8 encoding may be used within theory texts (both
  4624 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4625 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4626 
  4627   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4628   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4629 
  4630 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4631 Classical Reasoner.  Typical big applications run around 2 times
  4632 faster.
  4633 
  4634 
  4635 *** Document preparation ***
  4636 
  4637 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4638 of raw sources.  Only those symbols that do not require additional
  4639 LaTeX packages (depending on comments in isabellesym.sty) are
  4640 displayed properly, everything else is left verbatim.  isatool display
  4641 and isatool print are used as front ends (these are subject to the
  4642 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4643 
  4644 * Command tags control specific markup of certain regions of text,
  4645 notably folding and hiding.  Predefined tags include "theory" (for
  4646 theory begin and end), "proof" for proof commands, and "ML" for
  4647 commands involving ML code; the additional tags "visible" and
  4648 "invisible" are unused by default.  Users may give explicit tag
  4649 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4650 interpretation of tags is determined by the LaTeX job during document
  4651 preparation: see option -V of isatool usedir, or options -n and -t of
  4652 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4653 \isadroptag.
  4654 
  4655 Several document versions may be produced at the same time via isatool
  4656 usedir (the generated index.html will link all of them).  Typical
  4657 specifications include ''-V document=theory,proof,ML'' to present
  4658 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4659 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4660 these parts without any formal replacement text.  The Isabelle site
  4661 default settings produce ''document'' and ''outline'' versions as
  4662 specified above.
  4663 
  4664 * Several new antiquotations:
  4665 
  4666   @{term_type term} prints a term with its type annotated;
  4667 
  4668   @{typeof term} prints the type of a term;
  4669 
  4670   @{const const} is the same as @{term const}, but checks that the
  4671   argument is a known logical constant;
  4672 
  4673   @{term_style style term} and @{thm_style style thm} print a term or
  4674   theorem applying a "style" to it
  4675 
  4676   @{ML text}
  4677 
  4678 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4679 definitions, equations, inequations etc., 'concl' printing only the
  4680 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4681 to print the specified premise.  TermStyle.add_style provides an ML
  4682 interface for introducing further styles.  See also the "LaTeX Sugar"
  4683 document practical applications.  The ML antiquotation prints
  4684 type-checked ML expressions verbatim.
  4685 
  4686 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4687 and 'text' support optional locale specification '(in loc)', which
  4688 specifies the default context for interpreting antiquotations.  For
  4689 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4690 
  4691 * Option 'locale=NAME' of antiquotations specifies an alternative
  4692 context interpreting the subsequent argument.  For example: @{thm
  4693 [locale=lattice] inf_assoc}.
  4694 
  4695 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4696 a proof context.
  4697 
  4698 * Proper output of antiquotations for theory commands involving a
  4699 proof context (such as 'locale' or 'theorem (in loc) ...').
  4700 
  4701 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4702 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4703 
  4704 * isatool usedir: new option -C (default true) controls whether option
  4705 -D should include a copy of the original document directory; -C false
  4706 prevents unwanted effects such as copying of administrative CVS data.
  4707 
  4708 
  4709 *** Pure ***
  4710 
  4711 * Considerably improved version of 'constdefs' command.  Now performs
  4712 automatic type-inference of declared constants; additional support for
  4713 local structure declarations (cf. locales and HOL records), see also
  4714 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4715 sequential dependencies of definitions within a single 'constdefs'
  4716 section; moreover, the declared name needs to be an identifier.  If
  4717 all fails, consider to fall back on 'consts' and 'defs' separately.
  4718 
  4719 * Improved indexed syntax and implicit structures.  First of all,
  4720 indexed syntax provides a notational device for subscripted
  4721 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4722 expressions.  Secondly, in a local context with structure
  4723 declarations, number indexes \<^sub>n or the empty index (default
  4724 number 1) refer to a certain fixed variable implicitly; option
  4725 show_structs controls printing of implicit structures.  Typical
  4726 applications of these concepts involve record types and locales.
  4727 
  4728 * New command 'no_syntax' removes grammar declarations (and
  4729 translations) resulting from the given syntax specification, which is
  4730 interpreted in the same manner as for the 'syntax' command.
  4731 
  4732 * 'Advanced' translation functions (parse_translation etc.) may depend
  4733 on the signature of the theory context being presently used for
  4734 parsing/printing, see also isar-ref manual.
  4735 
  4736 * Improved 'oracle' command provides a type-safe interface to turn an
  4737 ML expression of type theory -> T -> term into a primitive rule of
  4738 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4739 is already included here); see also FOL/ex/IffExample.thy;
  4740 INCOMPATIBILITY.
  4741 
  4742 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4743 before); "cI" is no longer bound, use "c.intro" instead.
  4744 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4745 axclasses vs. locales.
  4746 
  4747 * Improved internal renaming of symbolic identifiers -- attach primes
  4748 instead of base 26 numbers.
  4749 
  4750 * New flag show_question_marks controls printing of leading question
  4751 marks in schematic variable names.
  4752 
  4753 * In schematic variable names, *any* symbol following \<^isub> or
  4754 \<^isup> is now treated as part of the base name.  For example, the
  4755 following works without printing of awkward ".0" indexes:
  4756 
  4757   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4758     by simp
  4759 
  4760 * Inner syntax includes (*(*nested*) comments*).
  4761 
  4762 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4763 annotations as "(00...)".
  4764 
  4765 * Clear separation of logical types and nonterminals, where the latter
  4766 may only occur in 'syntax' specifications or type abbreviations.
  4767 Before that distinction was only partially implemented via type class
  4768 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4769 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4770 exotic syntax specifications may require further adaption
  4771 (e.g. Cube/Cube.thy).
  4772 
  4773 * Removed obsolete type class "logic", use the top sort {} instead.
  4774 Note that non-logical types should be declared as 'nonterminals'
  4775 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4776 specifications.
  4777 
  4778 * Attributes 'induct' and 'cases': type or set names may now be
  4779 locally fixed variables as well.
  4780 
  4781 * Simplifier: can now control the depth to which conditional rewriting
  4782 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4783 Limit.
  4784 
  4785 * Simplifier: simplification procedures may now take the current
  4786 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4787 interface), which is very useful for calling the Simplifier
  4788 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4789 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4790 low-level mk_simproc no longer applies Logic.varify internally, to
  4791 allow for use in a context of fixed variables.
  4792 
  4793 * thin_tac now works even if the assumption being deleted contains !!
  4794 or ==>.  More generally, erule now works even if the major premise of
  4795 the elimination rule contains !! or ==>.
  4796 
  4797 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4798 
  4799 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4800 from Pure, which contains all common declarations already.  Both
  4801 theories are defined via plain Isabelle/Isar .thy files.
  4802 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4803 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4804 use isatool fixcpure to adapt your theory and ML sources.
  4805 
  4806 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4807 selections of theorems in named facts via index ranges.
  4808 
  4809 * 'print_theorems': in theory mode, really print the difference
  4810 wrt. the last state (works for interactive theory development only),
  4811 in proof mode print all local facts (cf. 'print_facts');
  4812 
  4813 * 'hide': option '(open)' hides only base names.
  4814 
  4815 * More efficient treatment of intermediate checkpoints in interactive
  4816 theory development.
  4817 
  4818 * Code generator is now invoked via code_module (incremental code
  4819 generation) and code_library (modular code generation, ML structures
  4820 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4821 must be quoted when used as identifiers.
  4822 
  4823 * New 'value' command for reading, evaluating and printing terms using
  4824 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4825 quoted when used as identifier.
  4826 
  4827 
  4828 *** Locales ***
  4829 
  4830 * New commands for the interpretation of locale expressions in
  4831 theories (1), locales (2) and proof contexts (3).  These generate
  4832 proof obligations from the expression specification.  After the
  4833 obligations have been discharged, theorems of the expression are added
  4834 to the theory, target locale or proof context.  The synopsis of the
  4835 commands is a follows:
  4836 
  4837   (1) interpretation expr inst
  4838   (2) interpretation target < expr
  4839   (3) interpret expr inst
  4840 
  4841 Interpretation in theories and proof contexts require a parameter
  4842 instantiation of terms from the current context.  This is applied to
  4843 specifications and theorems of the interpreted expression.
  4844 Interpretation in locales only permits parameter renaming through the
  4845 locale expression.  Interpretation is smart in that interpretations
  4846 that are active already do not occur in proof obligations, neither are
  4847 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4848 inspect active interpretations of a particular locale.  For details,
  4849 see the Isar Reference manual.  Examples can be found in
  4850 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4851 
  4852 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4853 'interpret' instead.
  4854 
  4855 * New context element 'constrains' for adding type constraints to
  4856 parameters.
  4857 
  4858 * Context expressions: renaming of parameters with syntax
  4859 redeclaration.
  4860 
  4861 * Locale declaration: 'includes' disallowed.
  4862 
  4863 * Proper static binding of attribute syntax -- i.e. types / terms /
  4864 facts mentioned as arguments are always those of the locale definition
  4865 context, independently of the context of later invocations.  Moreover,
  4866 locale operations (renaming and type / term instantiation) are applied
  4867 to attribute arguments as expected.
  4868 
  4869 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4870 actual attributes; rare situations may require Attrib.attribute to
  4871 embed those attributes into Attrib.src that lack concrete syntax.
  4872 Attribute implementations need to cooperate properly with the static
  4873 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4874 Attrib.XXX_thm etc. already do the right thing without further
  4875 intervention.  Only unusual applications -- such as "where" or "of"
  4876 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4877 on the context and the facts involved -- may have to assign parsed
  4878 values to argument tokens explicitly.
  4879 
  4880 * Changed parameter management in theorem generation for long goal
  4881 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4882 theorem statement in rare situations.
  4883 
  4884 * Locale inspection command 'print_locale' omits notes elements.  Use
  4885 'print_locale!' to have them included in the output.
  4886 
  4887 
  4888 *** Provers ***
  4889 
  4890 * Provers/hypsubst.ML: improved version of the subst method, for
  4891 single-step rewriting: it now works in bound variable contexts. New is
  4892 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4893 rewrite a different subterm than the original subst method, which is
  4894 still available as 'simplesubst'.
  4895 
  4896 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4897 and quasi orders.
  4898 
  4899 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4900 reflexive-transitive closure of relations.
  4901 
  4902 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4903 limit (previously hard-coded with a value of 20) user-definable.
  4904 
  4905 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4906 is peformed already.  Object-logics merely need to finish their
  4907 initial simpset configuration as before.  INCOMPATIBILITY.
  4908 
  4909 
  4910 *** HOL ***
  4911 
  4912 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4913 
  4914   syntax (epsilon)
  4915     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4916 
  4917 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4918 and x-symbol; use option '-m epsilon' to get it actually printed.
  4919 Moreover, the mathematically important symbolic identifier \<epsilon>
  4920 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4921 
  4922 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  4923 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  4924 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  4925 support corresponding Isar calculations.
  4926 
  4927 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  4928 instead of ":".
  4929 
  4930 * theory SetInterval: changed the syntax for open intervals:
  4931 
  4932   Old       New
  4933   {..n(}    {..<n}
  4934   {)n..}    {n<..}
  4935   {m..n(}   {m..<n}
  4936   {)m..n}   {m<..n}
  4937   {)m..n(}  {m<..<n}
  4938 
  4939 The old syntax is still supported but will disappear in the next
  4940 release.  For conversion use the following Emacs search and replace
  4941 patterns (these are not perfect but work quite well):
  4942 
  4943   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  4944   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  4945 
  4946 * Theory Commutative_Ring (in Library): method comm_ring for proving
  4947 equalities in commutative rings; method 'algebra' provides a generic
  4948 interface.
  4949 
  4950 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  4951 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  4952 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  4953 be a tuple pattern.
  4954 
  4955 Some new syntax forms are available:
  4956 
  4957   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  4958   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  4959   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  4960   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  4961 
  4962 The latter form "\<Sum>x < k. e" used to be based on a separate
  4963 function "Summation", which has been discontinued.
  4964 
  4965 * theory Finite_Set: in structured induction proofs, the insert case
  4966 is now 'case (insert x F)' instead of the old counterintuitive 'case
  4967 (insert F x)'.
  4968 
  4969 * The 'refute' command has been extended to support a much larger
  4970 fragment of HOL, including axiomatic type classes, constdefs and
  4971 typedefs, inductive datatypes and recursion.
  4972 
  4973 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  4974 Requires zChaff with proof generation to be installed.  See
  4975 HOL/ex/SAT_Examples.thy for examples.
  4976 
  4977 * Datatype induction via method 'induct' now preserves the name of the
  4978 induction variable. For example, when proving P(xs::'a list) by
  4979 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  4980 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  4981 in unstructured proof scripts.
  4982 
  4983 * Reworked implementation of records.  Improved scalability for
  4984 records with many fields, avoiding performance problems for type
  4985 inference. Records are no longer composed of nested field types, but
  4986 of nested extension types. Therefore the record type only grows linear
  4987 in the number of extensions and not in the number of fields.  The
  4988 top-level (users) view on records is preserved.  Potential
  4989 INCOMPATIBILITY only in strange cases, where the theory depends on the
  4990 old record representation. The type generated for a record is called
  4991 <record_name>_ext_type.
  4992 
  4993 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  4994 proofs triggered by a record definition or a simproc (if
  4995 quick_and_dirty is enabled).  Definitions of large records can take
  4996 quite long.
  4997 
  4998 New simproc record_upd_simproc for simplification of multiple record
  4999 updates enabled by default.  Moreover, trivial updates are also
  5000 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  5001 occasionally, since simplification is more powerful by default.
  5002 
  5003 * typedef: proper support for polymorphic sets, which contain extra
  5004 type-variables in the term.
  5005 
  5006 * Simplifier: automatically reasons about transitivity chains
  5007 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  5008 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  5009 old proofs break occasionally as simplification may now solve more
  5010 goals than previously.
  5011 
  5012 * Simplifier: converts x <= y into x = y if assumption y <= x is
  5013 present.  Works for all partial orders (class "order"), in particular
  5014 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  5015 just like y <= x.
  5016 
  5017 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  5018 bound variable or a constant then the let is unfolded.  Otherwise
  5019 first a is simplified to b, and then f b is simplified to g. If
  5020 possible we abstract b from g arriving at "let x = b in h x",
  5021 otherwise we unfold the let and arrive at g.  The simproc can be
  5022 enabled/disabled by the reference use_let_simproc.  Potential
  5023 INCOMPATIBILITY since simplification is more powerful by default.
  5024 
  5025 * Classical reasoning: the meson method now accepts theorems as arguments.
  5026 
  5027 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  5028 jobs to provide advice on the provability of subgoals.
  5029 
  5030 * Theory OrderedGroup and Ring_and_Field: various additions and
  5031 improvements to faciliate calculations involving equalities and
  5032 inequalities.
  5033 
  5034 The following theorems have been eliminated or modified
  5035 (INCOMPATIBILITY):
  5036 
  5037   abs_eq             now named abs_of_nonneg
  5038   abs_of_ge_0        now named abs_of_nonneg
  5039   abs_minus_eq       now named abs_of_nonpos
  5040   imp_abs_id         now named abs_of_nonneg
  5041   imp_abs_neg_id     now named abs_of_nonpos
  5042   mult_pos           now named mult_pos_pos
  5043   mult_pos_le        now named mult_nonneg_nonneg
  5044   mult_pos_neg_le    now named mult_nonneg_nonpos
  5045   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5046   mult_neg           now named mult_neg_neg
  5047   mult_neg_le        now named mult_nonpos_nonpos
  5048 
  5049 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5050      
  5051      zero_le_square
  5052      not_square_less_zero 
  5053 
  5054   The following lemmas have been deleted from Real/RealPow:
  5055   
  5056      realpow_zero_zero
  5057      realpow_two
  5058      realpow_less
  5059      zero_le_power
  5060      realpow_two_le
  5061      abs_realpow_two
  5062      realpow_two_abs     
  5063 
  5064 * Theory Parity: added rules for simplifying exponents.
  5065 
  5066 * Theory List:
  5067 
  5068 The following theorems have been eliminated or modified
  5069 (INCOMPATIBILITY):
  5070 
  5071   list_all_Nil       now named list_all.simps(1)
  5072   list_all_Cons      now named list_all.simps(2)
  5073   list_all_conv      now named list_all_iff
  5074   set_mem_eq         now named mem_iff
  5075 
  5076 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5077 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5078 
  5079 
  5080 *** HOL-Complex ***
  5081 
  5082 * Theory RealDef: better support for embedding natural numbers and
  5083 integers in the reals.
  5084 
  5085 The following theorems have been eliminated or modified
  5086 (INCOMPATIBILITY):
  5087 
  5088   exp_ge_add_one_self  now requires no hypotheses
  5089   real_of_int_add      reversed direction of equality (use [symmetric])
  5090   real_of_int_minus    reversed direction of equality (use [symmetric])
  5091   real_of_int_diff     reversed direction of equality (use [symmetric])
  5092   real_of_int_mult     reversed direction of equality (use [symmetric])
  5093 
  5094 * Theory RComplete: expanded support for floor and ceiling functions.
  5095 
  5096 * Theory Ln is new, with properties of the natural logarithm
  5097 
  5098 * Hyperreal: There is a new type constructor "star" for making
  5099 nonstandard types.  The old type names are now type synonyms:
  5100 
  5101   hypreal = real star
  5102   hypnat = nat star
  5103   hcomplex = complex star
  5104 
  5105 * Hyperreal: Many groups of similarly-defined constants have been
  5106 replaced by polymorphic versions (INCOMPATIBILITY):
  5107 
  5108   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5109 
  5110   starset      <-- starsetNat, starsetC
  5111   *s*          <-- *sNat*, *sc*
  5112   starset_n    <-- starsetNat_n, starsetC_n
  5113   *sn*         <-- *sNatn*, *scn*
  5114   InternalSets <-- InternalNatSets, InternalCSets
  5115 
  5116   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5117   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5118   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5119   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5120   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5121 
  5122 * Hyperreal: Many type-specific theorems have been removed in favor of
  5123 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5124 
  5125   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5126   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5127   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5128   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5129   right_minus <-- hypreal_add_minus
  5130   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5131   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5132   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5133   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5134   mult_1_right <-- hcomplex_mult_one_right
  5135   mult_zero_left <-- hcomplex_mult_zero_left
  5136   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5137   right_distrib <-- hypnat_add_mult_distrib2
  5138   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5139   right_inverse <-- hypreal_mult_inverse
  5140   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5141   order_refl <-- {hypreal,hypnat}_le_refl
  5142   order_trans <-- {hypreal,hypnat}_le_trans
  5143   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5144   order_less_le <-- {hypreal,hypnat}_less_le
  5145   linorder_linear <-- {hypreal,hypnat}_le_linear
  5146   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5147   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5148   add_nonneg_nonneg <-- hypreal_le_add_order
  5149 
  5150 * Hyperreal: Separate theorems having to do with type-specific
  5151 versions of constants have been merged into theorems that apply to the
  5152 new polymorphic constants (INCOMPATIBILITY):
  5153 
  5154   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5155   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5156   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5157   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5158   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5159   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5160   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5161   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5162   STAR_diff <-- {STAR,STARC}_diff
  5163   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5164     STARC_hcomplex_of_complex}_image_subset
  5165   starset_n_Un <-- starset{Nat,C}_n_Un
  5166   starset_n_Int <-- starset{Nat,C}_n_Int
  5167   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5168   starset_n_diff <-- starset{Nat,C}_n_diff
  5169   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5170   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5171   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5172   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5173   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5174   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5175   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5176   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5177   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5178   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5179   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5180   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5181   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5182   starfun_diff <-- starfun{C,RC,CR}_diff
  5183   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5184   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5185   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5186   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5187   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5188   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5189   starfun_Id <-- starfunC_Id
  5190   starfun_approx <-- starfun{Nat,CR}_approx
  5191   starfun_capprox <-- starfun{C,RC}_capprox
  5192   starfun_abs <-- starfunNat_rabs
  5193   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5194   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5195   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5196   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5197   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5198   starfun_add_approx <-- starfunCR_add_approx
  5199   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5200   starfun_divide <-- starfun{C,CR,RC}_divide
  5201   starfun_n <-- starfun{Nat,C}_n
  5202   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5203   starfun_n_add <-- starfun{Nat,C}_n_add
  5204   starfun_n_add_minus <-- starfunNat_n_add_minus
  5205   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5206   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5207   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5208 
  5209   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5210   star_n_minus <-- {hypreal,hcomplex}_minus
  5211   star_n_diff <-- {hypreal,hcomplex}_diff
  5212   star_n_mult <-- {hypreal,hcomplex}_mult
  5213   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5214   star_n_le <-- {hypreal,hypnat}_le
  5215   star_n_less <-- {hypreal,hypnat}_less
  5216   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5217   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5218   star_n_abs <-- hypreal_hrabs
  5219   star_n_divide <-- hcomplex_divide
  5220 
  5221   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5222   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5223   star_of_diff <-- hypreal_of_real_diff
  5224   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5225   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5226   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5227   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5228   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5229   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5230   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5231   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5232   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5233   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5234   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5235   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5236   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5237   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5238   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5239   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5240   star_of_power <-- hypreal_of_real_power
  5241   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5242 
  5243 * Hyperreal: new method "transfer" that implements the transfer
  5244 principle of nonstandard analysis. With a subgoal that mentions
  5245 nonstandard types like "'a star", the command "apply transfer"
  5246 replaces it with an equivalent one that mentions only standard types.
  5247 To be successful, all free variables must have standard types; non-
  5248 standard variables must have explicit universal quantifiers.
  5249 
  5250 * Hyperreal: A theory of Taylor series.
  5251 
  5252 
  5253 *** HOLCF ***
  5254 
  5255 * Discontinued special version of 'constdefs' (which used to support
  5256 continuous functions) in favor of the general Pure one with full
  5257 type-inference.
  5258 
  5259 * New simplification procedure for solving continuity conditions; it
  5260 is much faster on terms with many nested lambda abstractions (cubic
  5261 instead of exponential time).
  5262 
  5263 * New syntax for domain package: selector names are now optional.
  5264 Parentheses should be omitted unless argument is lazy, for example:
  5265 
  5266   domain 'a stream = cons "'a" (lazy "'a stream")
  5267 
  5268 * New command 'fixrec' for defining recursive functions with pattern
  5269 matching; defining multiple functions with mutual recursion is also
  5270 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5271 sinr, or any data constructor defined by the domain package. The given
  5272 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5273 syntax and examples.
  5274 
  5275 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5276 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5277 but the proof obligation additionally includes an admissibility
  5278 requirement. The packages generate instances of class cpo or pcpo,
  5279 with continuity and strictness theorems for Rep and Abs.
  5280 
  5281 * HOLCF: Many theorems have been renamed according to a more standard naming
  5282 scheme (INCOMPATIBILITY):
  5283 
  5284   foo_inject:  "foo$x = foo$y ==> x = y"
  5285   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5286   foo_less:    "(foo$x << foo$y) = (x << y)"
  5287   foo_strict:  "foo$UU = UU"
  5288   foo_defined: "... ==> foo$x ~= UU"
  5289   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5290 
  5291 
  5292 *** ZF ***
  5293 
  5294 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5295 including the First Isomorphism Theorem (on quotienting by the kernel
  5296 of a homomorphism).
  5297 
  5298 * ZF/Simplifier: install second copy of type solver that actually
  5299 makes use of TC rules declared to Isar proof contexts (or locales);
  5300 the old version is still required for ML proof scripts.
  5301 
  5302 
  5303 *** Cube ***
  5304 
  5305 * Converted to Isar theory format; use locales instead of axiomatic
  5306 theories.
  5307 
  5308 
  5309 *** ML ***
  5310 
  5311 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5312 for ||>, ||>>, |>>,
  5313 
  5314 * Pure/library.ML no longer defines its own option datatype, but uses
  5315 that of the SML basis, which has constructors NONE and SOME instead of
  5316 None and Some, as well as exception Option.Option instead of OPTION.
  5317 The functions the, if_none, is_some, is_none have been adapted
  5318 accordingly, while Option.map replaces apsome.
  5319 
  5320 * Pure/library.ML: the exception LIST has been given up in favour of
  5321 the standard exceptions Empty and Subscript, as well as
  5322 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5323 superceded by the standard hd and tl functions etc.
  5324 
  5325 A number of basic list functions are no longer exported to the ML
  5326 toplevel, as they are variants of predefined functions.  The following
  5327 suggests how one can translate existing code:
  5328 
  5329     rev_append xs ys = List.revAppend (xs, ys)
  5330     nth_elem (i, xs) = List.nth (xs, i)
  5331     last_elem xs = List.last xs
  5332     flat xss = List.concat xss
  5333     seq fs = List.app fs
  5334     partition P xs = List.partition P xs
  5335     mapfilter f xs = List.mapPartial f xs
  5336 
  5337 * Pure/library.ML: several combinators for linear functional
  5338 transformations, notably reverse application and composition:
  5339 
  5340   x |> f                f #> g
  5341   (x, y) |-> f          f #-> g
  5342 
  5343 * Pure/library.ML: introduced/changed precedence of infix operators:
  5344 
  5345   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5346   infix 2 ?;
  5347   infix 3 o oo ooo oooo;
  5348   infix 4 ~~ upto downto;
  5349 
  5350 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5351 infix operators.
  5352 
  5353 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5354 fold_map support linear functional transformations and nesting.  For
  5355 example:
  5356 
  5357   fold f [x1, ..., xN] y =
  5358     y |> f x1 |> ... |> f xN
  5359 
  5360   (fold o fold) f [xs1, ..., xsN] y =
  5361     y |> fold f xs1 |> ... |> fold f xsN
  5362 
  5363   fold f [x1, ..., xN] =
  5364     f x1 #> ... #> f xN
  5365 
  5366   (fold o fold) f [xs1, ..., xsN] =
  5367     fold f xs1 #> ... #> fold f xsN
  5368 
  5369 * Pure/library.ML: the following selectors on type 'a option are
  5370 available:
  5371 
  5372   the:               'a option -> 'a  (*partial*)
  5373   these:             'a option -> 'a  where 'a = 'b list
  5374   the_default: 'a -> 'a option -> 'a
  5375   the_list:          'a option -> 'a list
  5376 
  5377 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5378 basic operations for association lists, following natural argument
  5379 order; moreover the explicit equality predicate passed here avoids
  5380 potentially expensive polymorphic runtime equality checks.
  5381 The old functions may be expressed as follows:
  5382 
  5383   assoc = uncurry (AList.lookup (op =))
  5384   assocs = these oo AList.lookup (op =)
  5385   overwrite = uncurry (AList.update (op =)) o swap
  5386 
  5387 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5388 
  5389   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5390   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5391 
  5392 replacing make_keylist and keyfilter (occassionally used)
  5393 Naive rewrites:
  5394 
  5395   make_keylist = AList.make
  5396   keyfilter = AList.find (op =)
  5397 
  5398 * eq_fst and eq_snd now take explicit equality parameter, thus
  5399   avoiding eqtypes. Naive rewrites:
  5400 
  5401     eq_fst = eq_fst (op =)
  5402     eq_snd = eq_snd (op =)
  5403 
  5404 * Removed deprecated apl and apr (rarely used).
  5405   Naive rewrites:
  5406 
  5407     apl (n, op) =>>= curry op n
  5408     apr (op, m) =>>= fn n => op (n, m)
  5409 
  5410 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5411 provides a reasonably efficient light-weight implementation of sets as
  5412 lists.
  5413 
  5414 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5415 few new operations; existing lookup and update are now curried to
  5416 follow natural argument order (for use with fold etc.);
  5417 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5418 
  5419 * Pure/General: output via the Isabelle channels of
  5420 writeln/warning/error etc. is now passed through Output.output, with a
  5421 hook for arbitrary transformations depending on the print_mode
  5422 (cf. Output.add_mode -- the first active mode that provides a output
  5423 function wins).  Already formatted output may be embedded into further
  5424 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5425 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5426 accommodate easy composition of diagnostic messages etc.  Programmers
  5427 rarely need to care about Output.output or Output.raw at all, with
  5428 some notable exceptions: Output.output is required when bypassing the
  5429 standard channels (writeln etc.), or in token translations to produce
  5430 properly formatted results; Output.raw is required when capturing
  5431 already output material that will eventually be presented to the user
  5432 a second time.  For the default print mode, both Output.output and
  5433 Output.raw have no effect.
  5434 
  5435 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5436 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5437 cumulative results are displayed at the end of a batch session.
  5438 
  5439 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5440 replaced by File.platform_path and File.shell_path (with appropriate
  5441 hooks).  This provides a clean interface for unusual systems where the
  5442 internal and external process view of file names are different.
  5443 
  5444 * Pure: more efficient orders for basic syntactic entities: added
  5445 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5446 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5447 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5448 orders now -- potential INCOMPATIBILITY for code that depends on a
  5449 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5450 Library.sort_strings on result).
  5451 
  5452 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5453 fold_types traverse types/terms from left to right, observing natural
  5454 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5455 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5456 
  5457 * Pure: name spaces have been refined, with significant changes of the
  5458 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5459 to extern(_table).  The plain name entry path is superceded by a
  5460 general 'naming' context, which also includes the 'policy' to produce
  5461 a fully qualified name and external accesses of a fully qualified
  5462 name; NameSpace.extend is superceded by context dependent
  5463 Sign.declare_name.  Several theory and proof context operations modify
  5464 the naming context.  Especially note Theory.restore_naming and
  5465 ProofContext.restore_naming to get back to a sane state; note that
  5466 Theory.add_path is no longer sufficient to recover from
  5467 Theory.absolute_path in particular.
  5468 
  5469 * Pure: new flags short_names (default false) and unique_names
  5470 (default true) for controlling output of qualified names.  If
  5471 short_names is set, names are printed unqualified.  If unique_names is
  5472 reset, the name prefix is reduced to the minimum required to achieve
  5473 the original result when interning again, even if there is an overlap
  5474 with earlier declarations.
  5475 
  5476 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5477 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5478 (useful for printing error messages).  INCOMPATIBILITY.
  5479 
  5480 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5481 Theory.theory are now identified, referring to the universal
  5482 Context.theory (see Pure/context.ML).  Actual signature and theory
  5483 content is managed as theory data.  The old code and interfaces were
  5484 spread over many files and structures; the new arrangement introduces
  5485 considerable INCOMPATIBILITY to gain more clarity:
  5486 
  5487   Context -- theory management operations (name, identity, inclusion,
  5488     parents, ancestors, merge, etc.), plus generic theory data;
  5489 
  5490   Sign -- logical signature and syntax operations (declaring consts,
  5491     types, etc.), plus certify/read for common entities;
  5492 
  5493   Theory -- logical theory operations (stating axioms, definitions,
  5494     oracles), plus a copy of logical signature operations (consts,
  5495     types, etc.); also a few basic management operations (Theory.copy,
  5496     Theory.merge, etc.)
  5497 
  5498 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5499 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5500 for convenience -- they merely return the theory.
  5501 
  5502 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5503 
  5504 * Pure: the Isar proof context type is already defined early in Pure
  5505 as Context.proof (note that ProofContext.context and Proof.context are
  5506 aliases, where the latter is the preferred name).  This enables other
  5507 Isabelle components to refer to that type even before Isar is present.
  5508 
  5509 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5510 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5511 any of these kinds.  For example, Sign.intern typeK is now
  5512 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5513 Theory.hide_types.  Also note that former
  5514 Theory.hide_classes/types/consts are now
  5515 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5516 internalize their arguments!  INCOMPATIBILITY.
  5517 
  5518 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5519 datatype thmref (with constructors Name and NameSelection) instead of
  5520 plain string -- INCOMPATIBILITY;
  5521 
  5522 * Pure: cases produced by proof methods specify options, where NONE
  5523 means to remove case bindings -- INCOMPATIBILITY in
  5524 (RAW_)METHOD_CASES.
  5525 
  5526 * Pure: the following operations retrieve axioms or theorems from a
  5527 theory node or theory hierarchy, respectively:
  5528 
  5529   Theory.axioms_of: theory -> (string * term) list
  5530   Theory.all_axioms_of: theory -> (string * term) list
  5531   PureThy.thms_of: theory -> (string * thm) list
  5532   PureThy.all_thms_of: theory -> (string * thm) list
  5533 
  5534 * Pure: print_tac now outputs the goal through the trace channel.
  5535 
  5536 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5537 Reference Toplevel.debug (default false) controls detailed printing
  5538 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5539 controls execution profiling -- set to 1 for time and 2 for space
  5540 (both increase the runtime).
  5541 
  5542 * Isar session: The initial use of ROOT.ML is now always timed,
  5543 i.e. the log will show the actual process times, in contrast to the
  5544 elapsed wall-clock time that the outer shell wrapper produces.
  5545 
  5546 * Simplifier: improved handling of bound variables (nameless
  5547 representation, avoid allocating new strings).  Simprocs that invoke
  5548 the Simplifier recursively should use Simplifier.inherit_bounds to
  5549 avoid local name clashes.  Failure to do so produces warnings
  5550 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5551 for further details.
  5552 
  5553 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5554 bindings for all theorems stored within a given theory; this may help
  5555 in porting non-Isar theories to Isar ones, while keeping ML proof
  5556 scripts for the time being.
  5557 
  5558 * ML operator HTML.with_charset specifies the charset begin used for
  5559 generated HTML files.  For example:
  5560 
  5561   HTML.with_charset "utf-8" use_thy "Hebrew";
  5562   HTML.with_charset "utf-8" use_thy "Chinese";
  5563 
  5564 
  5565 *** System ***
  5566 
  5567 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5568 isabelle, isatool etc.).
  5569 
  5570 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5571 isatool doc, isatool mkdir, display_drafts etc.).
  5572 
  5573 * isatool usedir: option -f allows specification of the ML file to be
  5574 used by Isabelle; default is ROOT.ML.
  5575 
  5576 * New isatool version outputs the version identifier of the Isabelle
  5577 distribution being used.
  5578 
  5579 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5580 (containing Boolean satisfiability problems) into Isabelle/HOL
  5581 theories.
  5582 
  5583 
  5584 
  5585 New in Isabelle2004 (April 2004)
  5586 --------------------------------
  5587 
  5588 *** General ***
  5589 
  5590 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5591   Replaces linorder.ML.
  5592 
  5593 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5594   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5595   (\<a>...\<z>), are now considered normal letters, and can therefore
  5596   be used anywhere where an ASCII letter (a...zA...Z) has until
  5597   now. COMPATIBILITY: This obviously changes the parsing of some
  5598   terms, especially where a symbol has been used as a binder, say
  5599   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5600   as an identifier.  Fix it by inserting a space around former
  5601   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5602   existing theory and ML files.
  5603 
  5604 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5605 
  5606 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5607   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5608   a normal (but invisible) letter. For multiple letter subscripts repeat
  5609   \<^isub> like this: x\<^isub>1\<^isub>2.
  5610 
  5611 * Pure: There are now sub-/superscripts that can span more than one
  5612   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5613   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5614   superscript. The new control characters are not identifier parts.
  5615 
  5616 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5617   content of "..." to the latex file instead of \isacntrl... . The "..."
  5618   may consist of any printable characters excluding the end bracket >.
  5619 
  5620 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5621   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5622   declare constants "final", which prevents their being given a definition
  5623   later.  It is useful for constants whose behaviour is fixed axiomatically
  5624   rather than definitionally, such as the meta-logic connectives.
  5625 
  5626 * Pure: 'instance' now handles general arities with general sorts
  5627   (i.e. intersections of classes),
  5628 
  5629 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5630   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5631   It can be changed to alter the colors/layout of generated pages.
  5632 
  5633 
  5634 *** Isar ***
  5635 
  5636 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5637   cut_tac, subgoal_tac and thin_tac:
  5638   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5639     locales are no longer forced to write Isar proof scripts.
  5640     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5641     emulations.
  5642   - INCOMPATIBILITY: names of variables to be instantiated may no
  5643     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5644     This is consistent with the instantiation attribute "where".
  5645 
  5646 * Attributes "where" and "of":
  5647   - Now take type variables of instantiated theorem into account when reading
  5648     the instantiation string.  This fixes a bug that caused instantiated
  5649     theorems to have too special types in some circumstances.
  5650   - "where" permits explicit instantiations of type variables.
  5651 
  5652 * Calculation commands "moreover" and "also" no longer interfere with
  5653   current facts ("this"), admitting arbitrary combinations with "then"
  5654   and derived forms.
  5655 
  5656 * Locales:
  5657   - Goal statements involving the context element "includes" no longer
  5658     generate theorems with internal delta predicates (those ending on
  5659     "_axioms") in the premise.
  5660     Resolve particular premise with <locale>.intro to obtain old form.
  5661   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5662     specification and "includes" elements in goal statement.
  5663   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5664     [intro?] and [elim?] (respectively) by default.
  5665   - Experimental command for instantiation of locales in proof contexts:
  5666         instantiate <label>[<attrs>]: <loc>
  5667     Instantiates locale <loc> and adds all its theorems to the current context
  5668     taking into account their attributes.  Label and attrs are optional
  5669     modifiers, like in theorem declarations.  If present, names of
  5670     instantiated theorems are qualified with <label>, and the attributes
  5671     <attrs> are applied after any attributes these theorems might have already.
  5672       If the locale has assumptions, a chained fact of the form
  5673     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5674     are derived.  The command does not support old-style locales declared
  5675     with "locale (open)".
  5676       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5677 
  5678 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5679   (Isar) contexts.
  5680 
  5681 
  5682 *** HOL ***
  5683 
  5684 * Proof import: new image HOL4 contains the imported library from
  5685   the HOL4 system with about 2500 theorems. It is imported by
  5686   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5687   can be used like any other Isabelle image.  See
  5688   HOL/Import/HOL/README for more information.
  5689 
  5690 * Simplifier:
  5691   - Much improved handling of linear and partial orders.
  5692     Reasoners for linear and partial orders are set up for type classes
  5693     "linorder" and "order" respectively, and are added to the default simpset
  5694     as solvers.  This means that the simplifier can build transitivity chains
  5695     to solve goals from the assumptions.
  5696   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5697     of blast or auto after simplification become unnecessary because the goal
  5698     is solved by simplification already.
  5699 
  5700 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5701     all proved in axiomatic type classes for semirings, rings and fields.
  5702 
  5703 * Numerics:
  5704   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5705     now formalized using the Ring_and_Field theory mentioned above.
  5706   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5707     than before, because now they are set up once in a generic manner.
  5708   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5709     Look for the general versions in Ring_and_Field (and Power if they concern
  5710     exponentiation).
  5711 
  5712 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5713 
  5714 * Records:
  5715   - Record types are now by default printed with their type abbreviation
  5716     instead of the list of all field types. This can be configured via
  5717     the reference "print_record_type_abbr".
  5718   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5719     (not enabled by default).
  5720   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5721     EX x. x = sel r to True (not enabled by default).
  5722   - Tactic "record_split_simp_tac" to split and simplify records added.
  5723 
  5724 * 'specification' command added, allowing for definition by
  5725   specification.  There is also an 'ax_specification' command that
  5726   introduces the new constants axiomatically.
  5727 
  5728 * arith(_tac) is now able to generate counterexamples for reals as well.
  5729 
  5730 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5731 
  5732 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5733   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5734 
  5735 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5736   matrix theory to linear programming.
  5737 
  5738 * Unions and Intersections:
  5739   The latex output syntax of UN and INT has been changed
  5740   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5741   i.e. the index formulae has become a subscript.
  5742   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5743 
  5744 * Unions and Intersections over Intervals:
  5745   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5746   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5747   like in normal math, and corresponding versions for < and for intersection.
  5748 
  5749 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5750   lexicographic dictonary ordering has been added as "lexord".
  5751 
  5752 * ML: the legacy theory structures Int and List have been removed. They had
  5753   conflicted with ML Basis Library structures having the same names.
  5754 
  5755 * 'refute' command added to search for (finite) countermodels.  Only works
  5756   for a fragment of HOL.  The installation of an external SAT solver is
  5757   highly recommended.  See "HOL/Refute.thy" for details.
  5758 
  5759 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5760   formulae under an assignment of free variables to random values.
  5761   In contrast to 'refute', it can deal with inductive datatypes,
  5762   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5763   for examples.
  5764 
  5765 
  5766 *** HOLCF ***
  5767 
  5768 * Streams now come with concatenation and are part of the HOLCF image
  5769 
  5770 
  5771 
  5772 New in Isabelle2003 (May 2003)
  5773 ------------------------------
  5774 
  5775 *** General ***
  5776 
  5777 * Provers/simplifier:
  5778 
  5779   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5780     Assumptions are now subject to complete mutual simplification,
  5781     not just from left to right. The simplifier now preserves
  5782     the order of assumptions.
  5783 
  5784     Potential INCOMPATIBILITY:
  5785 
  5786     -- simp sometimes diverges where the old version did
  5787        not, e.g. invoking simp on the goal
  5788 
  5789         [| P (f x); y = x; f x = f y |] ==> Q
  5790 
  5791        now gives rise to the infinite reduction sequence
  5792 
  5793         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5794 
  5795        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5796        kind of problem.
  5797 
  5798     -- Tactics combining classical reasoner and simplification (such as auto)
  5799        are also affected by this change, because many of them rely on
  5800        simp. They may sometimes diverge as well or yield a different numbers
  5801        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5802        in case of problems. Sometimes subsequent calls to the classical
  5803        reasoner will fail because a preceeding call to the simplifier too
  5804        eagerly simplified the goal, e.g. deleted redundant premises.
  5805 
  5806   - The simplifier trace now shows the names of the applied rewrite rules
  5807 
  5808   - You can limit the number of recursive invocations of the simplifier
  5809     during conditional rewriting (where the simplifie tries to solve the
  5810     conditions before applying the rewrite rule):
  5811     ML "simp_depth_limit := n"
  5812     where n is an integer. Thus you can force termination where previously
  5813     the simplifier would diverge.
  5814 
  5815   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5816 
  5817   - No longer aborts on failed congruence proof.  Instead, the
  5818     congruence is ignored.
  5819 
  5820 * Pure: New generic framework for extracting programs from constructive
  5821   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5822   as HOL/Extraction for some case studies.
  5823 
  5824 * Pure: The main goal of the proof state is no longer shown by default, only
  5825 the subgoals. This behaviour is controlled by a new flag.
  5826    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5827 (ML: Proof.show_main_goal).
  5828 
  5829 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5830 rules whose conclusion matches subgoal 1:
  5831       PG menu: Isabelle/Isar -> Show me -> matching rules
  5832 The rules are ordered by how closely they match the subgoal.
  5833 In particular, rules that solve a subgoal outright are displayed first
  5834 (or rather last, the way they are printed).
  5835 (ML: ProofGeneral.print_intros())
  5836 
  5837 * Pure: New flag trace_unify_fail causes unification to print
  5838 diagnostic information (PG: in trace buffer) when it fails. This is
  5839 useful for figuring out why single step proofs like rule, erule or
  5840 assumption failed.
  5841 
  5842 * Pure: Locale specifications now produce predicate definitions
  5843 according to the body of text (covering assumptions modulo local
  5844 definitions); predicate "loc_axioms" covers newly introduced text,
  5845 while "loc" is cumulative wrt. all included locale expressions; the
  5846 latter view is presented only on export into the global theory
  5847 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5848 on the old view without predicates;
  5849 
  5850 * Pure: predefined locales "var" and "struct" are useful for sharing
  5851 parameters (as in CASL, for example); just specify something like
  5852 ``var x + var y + struct M'' as import;
  5853 
  5854 * Pure: improved thms_containing: proper indexing of facts instead of
  5855 raw theorems; check validity of results wrt. current name space;
  5856 include local facts of proof configuration (also covers active
  5857 locales), cover fixed variables in index; may use "_" in term
  5858 specification; an optional limit for the number of printed facts may
  5859 be given (the default is 40);
  5860 
  5861 * Pure: disallow duplicate fact bindings within new-style theory files
  5862 (batch-mode only);
  5863 
  5864 * Provers: improved induct method: assumptions introduced by case
  5865 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5866 the goal statement); "foo" still refers to all facts collectively;
  5867 
  5868 * Provers: the function blast.overloaded has been removed: all constants
  5869 are regarded as potentially overloaded, which improves robustness in exchange
  5870 for slight decrease in efficiency;
  5871 
  5872 * Provers/linorder: New generic prover for transitivity reasoning over
  5873 linear orders.  Note: this prover is not efficient!
  5874 
  5875 * Isar: preview of problems to finish 'show' now produce an error
  5876 rather than just a warning (in interactive mode);
  5877 
  5878 
  5879 *** HOL ***
  5880 
  5881 * arith(_tac)
  5882 
  5883  - Produces a counter example if it cannot prove a goal.
  5884    Note that the counter example may be spurious if the goal is not a formula
  5885    of quantifier-free linear arithmetic.
  5886    In ProofGeneral the counter example appears in the trace buffer.
  5887 
  5888  - Knows about div k and mod k where k is a numeral of type nat or int.
  5889 
  5890  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5891    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5892    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5893 
  5894 * simp's arithmetic capabilities have been enhanced a bit: it now
  5895 takes ~= in premises into account (by performing a case split);
  5896 
  5897 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5898 are distributed over a sum of terms;
  5899 
  5900 * New tactic "trans_tac" and method "trans" instantiate
  5901 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5902 "<=", "<" and "=").
  5903 
  5904 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5905 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5906 
  5907 * 'typedef' command has new option "open" to suppress the set
  5908 definition;
  5909 
  5910 * functions Min and Max on finite sets have been introduced (theory
  5911 Finite_Set);
  5912 
  5913 * attribute [symmetric] now works for relations as well; it turns
  5914 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5915 
  5916 * induct over a !!-quantified statement (say !!x1..xn):
  5917   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5918 
  5919 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5920 %x. None. Warning: empty_def now refers to the previously hidden definition
  5921 of the empty set.
  5922 
  5923 * Algebra: formalization of classical algebra.  Intended as base for
  5924 any algebraic development in Isabelle.  Currently covers group theory
  5925 (up to Sylow's theorem) and ring theory (Universal Property of
  5926 Univariate Polynomials).  Contributions welcome;
  5927 
  5928 * GroupTheory: deleted, since its material has been moved to Algebra;
  5929 
  5930 * Complex: new directory of the complex numbers with numeric constants,
  5931 nonstandard complex numbers, and some complex analysis, standard and
  5932 nonstandard (Jacques Fleuriot);
  5933 
  5934 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  5935 
  5936 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  5937 Fleuriot);
  5938 
  5939 * Real/HahnBanach: updated and adapted to locales;
  5940 
  5941 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  5942 Gray and Kramer);
  5943 
  5944 * UNITY: added the Meier-Sanders theory of progress sets;
  5945 
  5946 * MicroJava: bytecode verifier and lightweight bytecode verifier
  5947 as abstract algorithms, instantiated to the JVM;
  5948 
  5949 * Bali: Java source language formalization. Type system, operational
  5950 semantics, axiomatic semantics. Supported language features:
  5951 classes, interfaces, objects,virtual methods, static methods,
  5952 static/instance fields, arrays, access modifiers, definite
  5953 assignment, exceptions.
  5954 
  5955 
  5956 *** ZF ***
  5957 
  5958 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  5959 universe, etc.);
  5960 
  5961 * Main ZF: virtually all theories converted to new-style format;
  5962 
  5963 
  5964 *** ML ***
  5965 
  5966 * Pure: Tactic.prove provides sane interface for internal proofs;
  5967 omits the infamous "standard" operation, so this is more appropriate
  5968 than prove_goalw_cterm in many situations (e.g. in simprocs);
  5969 
  5970 * Pure: improved error reporting of simprocs;
  5971 
  5972 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  5973 up simprocs;
  5974 
  5975 
  5976 *** Document preparation ***
  5977 
  5978 * uses \par instead of \\ for line breaks in theory text. This may
  5979 shift some page breaks in large documents. To get the old behaviour
  5980 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  5981 
  5982 * minimized dependencies of isabelle.sty and isabellesym.sty on
  5983 other packages
  5984 
  5985 * \<euro> now needs package babel/greek instead of marvosym (which
  5986 broke \Rightarrow)
  5987 
  5988 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  5989 textcomp package)
  5990 
  5991 
  5992 
  5993 New in Isabelle2002 (March 2002)
  5994 --------------------------------
  5995 
  5996 *** Document preparation ***
  5997 
  5998 * greatly simplified document preparation setup, including more
  5999 graceful interpretation of isatool usedir -i/-d/-D options, and more
  6000 instructive isatool mkdir; users should basically be able to get
  6001 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  6002 users may run a separate document processing stage manually like this:
  6003 "isatool usedir -D output HOL Test && isatool document Test/output";
  6004 
  6005 * theory dependency graph may now be incorporated into documents;
  6006 isatool usedir -g true will produce session_graph.eps/.pdf for use
  6007 with \includegraphics of LaTeX;
  6008 
  6009 * proper spacing of consecutive markup elements, especially text
  6010 blocks after section headings;
  6011 
  6012 * support bold style (for single symbols only), input syntax is like
  6013 this: "\<^bold>\<alpha>" or "\<^bold>A";
  6014 
  6015 * \<bullet> is now output as bold \cdot by default, which looks much
  6016 better in printed text;
  6017 
  6018 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  6019 note that these symbols are currently unavailable in Proof General /
  6020 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  6021 
  6022 * isatool latex no longer depends on changed TEXINPUTS, instead
  6023 isatool document copies the Isabelle style files to the target
  6024 location;
  6025 
  6026 
  6027 *** Isar ***
  6028 
  6029 * Pure/Provers: improved proof by cases and induction;
  6030   - 'case' command admits impromptu naming of parameters (such as
  6031     "case (Suc n)");
  6032   - 'induct' method divinates rule instantiation from the inductive
  6033     claim; no longer requires excessive ?P bindings for proper
  6034     instantiation of cases;
  6035   - 'induct' method properly enumerates all possibilities of set/type
  6036     rules; as a consequence facts may be also passed through *type*
  6037     rules without further ado;
  6038   - 'induct' method now derives symbolic cases from the *rulified*
  6039     rule (before it used to rulify cases stemming from the internal
  6040     atomized version); this means that the context of a non-atomic
  6041     statement becomes is included in the hypothesis, avoiding the
  6042     slightly cumbersome show "PROP ?case" form;
  6043   - 'induct' may now use elim-style induction rules without chaining
  6044     facts, using ``missing'' premises from the goal state; this allows
  6045     rules stemming from inductive sets to be applied in unstructured
  6046     scripts, while still benefitting from proper handling of non-atomic
  6047     statements; NB: major inductive premises need to be put first, all
  6048     the rest of the goal is passed through the induction;
  6049   - 'induct' proper support for mutual induction involving non-atomic
  6050     rule statements (uses the new concept of simultaneous goals, see
  6051     below);
  6052   - append all possible rule selections, but only use the first
  6053     success (no backtracking);
  6054   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  6055   - undeclared rule case names default to numbers 1, 2, 3, ...;
  6056   - added 'print_induct_rules' (covered by help item in recent Proof
  6057     General versions);
  6058   - moved induct/cases attributes to Pure, methods to Provers;
  6059   - generic method setup instantiated for FOL and HOL;
  6060 
  6061 * Pure: support multiple simultaneous goal statements, for example
  6062 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  6063 meta-level mechanism, this acts as if several individual goals had
  6064 been stated separately; in particular common proof methods need to be
  6065 repeated in order to cover all claims; note that a single elimination
  6066 step is *not* sufficient to establish the two conjunctions, so this
  6067 fails:
  6068 
  6069   assume "A & B" then have A and B ..   (*".." fails*)
  6070 
  6071 better use "obtain" in situations as above; alternative refer to
  6072 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  6073 
  6074 * Pure: proper integration with ``locales''; unlike the original
  6075 version by Florian Kammller, Isar locales package high-level proof
  6076 contexts rather than raw logical ones (e.g. we admit to include
  6077 attributes everywhere); operations on locales include merge and
  6078 rename; support for implicit arguments (``structures''); simultaneous
  6079 type-inference over imports and text; see also HOL/ex/Locales.thy for
  6080 some examples;
  6081 
  6082 * Pure: the following commands have been ``localized'', supporting a
  6083 target locale specification "(in name)": 'lemma', 'theorem',
  6084 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  6085 stored both within the locale and at the theory level (exported and
  6086 qualified by the locale name);
  6087 
  6088 * Pure: theory goals may now be specified in ``long'' form, with
  6089 ad-hoc contexts consisting of arbitrary locale elements. for example
  6090 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  6091 definitions may be given, too); the result is a meta-level rule with
  6092 the context elements being discharged in the obvious way;
  6093 
  6094 * Pure: new proof command 'using' allows to augment currently used
  6095 facts after a goal statement ('using' is syntactically analogous to
  6096 'apply', but acts on the goal's facts only); this allows chained facts
  6097 to be separated into parts given before and after a claim, as in
  6098 ``from a and b have C using d and e <proof>'';
  6099 
  6100 * Pure: renamed "antecedent" case to "rule_context";
  6101 
  6102 * Pure: new 'judgment' command records explicit information about the
  6103 object-logic embedding (used by several tools internally); no longer
  6104 use hard-wired "Trueprop";
  6105 
  6106 * Pure: added 'corollary' command;
  6107 
  6108 * Pure: fixed 'token_translation' command;
  6109 
  6110 * Pure: removed obsolete 'exported' attribute;
  6111 
  6112 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  6113 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  6114 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  6115 
  6116 * Pure: method 'atomize' presents local goal premises as object-level
  6117 statements (atomic meta-level propositions); setup controlled via
  6118 rewrite rules declarations of 'atomize' attribute; example
  6119 application: 'induct' method with proper rule statements in improper
  6120 proof *scripts*;
  6121 
  6122 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  6123 now consider the syntactic context of assumptions, giving a better
  6124 chance to get type-inference of the arguments right (this is
  6125 especially important for locales);
  6126 
  6127 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  6128 mode;
  6129 
  6130 * Pure/obtain: the formal conclusion "thesis", being marked as
  6131 ``internal'', may no longer be reference directly in the text;
  6132 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  6133 situations;
  6134 
  6135 * Pure: generic 'sym' attribute which declares a rule both as pure
  6136 'elim?' and for the 'symmetric' operation;
  6137 
  6138 * Pure: marginal comments ``--'' may now occur just anywhere in the
  6139 text; the fixed correlation with particular command syntax has been
  6140 discontinued;
  6141 
  6142 * Pure: new method 'rules' is particularly well-suited for proof
  6143 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  6144 but often produces more compact proof terms with less detours;
  6145 
  6146 * Pure/Provers/classical: simplified integration with pure rule
  6147 attributes and methods; the classical "intro?/elim?/dest?"
  6148 declarations coincide with the pure ones; the "rule" method no longer
  6149 includes classically swapped intros; "intro" and "elim" methods no
  6150 longer pick rules from the context; also got rid of ML declarations
  6151 AddXIs/AddXEs/AddXDs; all of this has some potential for
  6152 INCOMPATIBILITY;
  6153 
  6154 * Provers/classical: attribute 'swapped' produces classical inversions
  6155 of introduction rules;
  6156 
  6157 * Provers/simplifier: 'simplified' attribute may refer to explicit
  6158 rules instead of full simplifier context; 'iff' attribute handles
  6159 conditional rules;
  6160 
  6161 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  6162 
  6163 * HOL: 'recdef' now fails on unfinished automated proofs, use
  6164 "(permissive)" option to recover old behavior;
  6165 
  6166 * HOL: 'inductive' no longer features separate (collective) attributes
  6167 for 'intros' (was found too confusing);
  6168 
  6169 * HOL: properly declared induction rules less_induct and
  6170 wf_induct_rule;
  6171 
  6172 
  6173 *** HOL ***
  6174 
  6175 * HOL: moved over to sane numeral syntax; the new policy is as
  6176 follows:
  6177 
  6178   - 0 and 1 are polymorphic constants, which are defined on any
  6179   numeric type (nat, int, real etc.);
  6180 
  6181   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  6182   binary representation internally;
  6183 
  6184   - type nat has special constructor Suc, and generally prefers Suc 0
  6185   over 1::nat and Suc (Suc 0) over 2::nat;
  6186 
  6187 This change may cause significant problems of INCOMPATIBILITY; here
  6188 are some hints on converting existing sources:
  6189 
  6190   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  6191   entities, so expressions involving "-" (unary or binary minus) need
  6192   to be spaced properly;
  6193 
  6194   - existing occurrences of "1" may need to be constraint "1::nat" or
  6195   even replaced by Suc 0; similar for old "2";
  6196 
  6197   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  6198 
  6199   - remove all special provisions on numerals in proofs;
  6200 
  6201 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  6202 representation (depends on bin_arith_simps in the default context);
  6203 
  6204 * HOL: symbolic syntax for x^2 (numeral 2);
  6205 
  6206 * HOL: the class of all HOL types is now called "type" rather than
  6207 "term"; INCOMPATIBILITY, need to adapt references to this type class
  6208 in axclass/classes, instance/arities, and (usually rare) occurrences
  6209 in typings (of consts etc.); internally the class is called
  6210 "HOL.type", ML programs should refer to HOLogic.typeS;
  6211 
  6212 * HOL/record package improvements:
  6213   - new derived operations "fields" to build a partial record section,
  6214     "extend" to promote a fixed record to a record scheme, and
  6215     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  6216     declared as simp by default;
  6217   - shared operations ("more", "fields", etc.) now need to be always
  6218     qualified) --- potential INCOMPATIBILITY;
  6219   - removed "make_scheme" operations (use "make" with "extend") --
  6220     INCOMPATIBILITY;
  6221   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  6222   - provides cases/induct rules for use with corresponding Isar
  6223     methods (for concrete records, record schemes, concrete more
  6224     parts, and schematic more parts -- in that order);
  6225   - internal definitions directly based on a light-weight abstract
  6226     theory of product types over typedef rather than datatype;
  6227 
  6228 * HOL: generic code generator for generating executable ML code from
  6229 specifications; specific support for HOL constructs such as inductive
  6230 datatypes and sets, as well as recursive functions; can be invoked
  6231 via 'generate_code' theory section;