NEWS
author wenzelm
Sun Jul 10 21:46:41 2011 +0200 (2011-07-10)
changeset 43743 8786e36b8142
parent 43737 592b32eb18a6
parent 43731 70072780e095
child 43752 0517a69de5d6
permissions -rw-r--r--
merged;
     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) has been discontinued.
    26 Note that the path element ~~ may be used to reference theories in the
    27 Isabelle home folder -- for instance, "~~/src/HOL/Library/FuncSet".
    28 INCOMPATIBILITY.
    29 
    30 * Various optional external tools are referenced more robustly and
    31 uniformly by explicit Isabelle settings as follows:
    32 
    33   ISABELLE_CSDP   (formerly CSDP_EXE)
    34   ISABELLE_GHC    (formerly EXEC_GHC or GHC_PATH)
    35   ISABELLE_OCAML  (formerly EXEC_OCAML)
    36   ISABELLE_SWIPL  (formerly EXEC_SWIPL)
    37   ISABELLE_YAP    (formerly EXEC_YAP)
    38 
    39 Note that automated detection from the file-system or search path has
    40 been discontinued.  INCOMPATIBILITY.
    41 
    42 * Name space: former unsynchronized references are now proper
    43 configuration options, with more conventional names:
    44 
    45   long_names   ~> names_long
    46   short_names  ~> names_short
    47   unique_names ~> names_unique
    48 
    49 Minor INCOMPATIBILITY, need to declare options in context like this:
    50 
    51   declare [[names_unique = false]]
    52 
    53 * Literal facts `prop` may contain dummy patterns, e.g. `_ = _`.  Note
    54 that the result needs to be unique, which means fact specifications
    55 may have to be refined after enriching a proof context.
    56 
    57 * Isabelle/Isar reference manual provides more formal references in
    58 syntax diagrams.
    59 
    60 
    61 *** HOL ***
    62 
    63 * Archimedian_Field.thy:
    64     floor now is defined as parameter of a separate type class floor_ceiling.
    65  
    66 * Finite_Set.thy: more coherent development of fold_set locales:
    67 
    68     locale fun_left_comm ~> locale comp_fun_commute
    69     locale fun_left_comm_idem ~> locale comp_fun_idem
    70     
    71 Both use point-free characterisation; interpretation proofs may need adjustment.
    72 INCOMPATIBILITY.
    73 
    74 * Code generation:
    75   - theory Library/Code_Char_ord provides native ordering of characters
    76     in the target language.
    77     
    78 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
    79 
    80 * Nitpick:
    81   - Added "need" and "total_consts" options.
    82   - Reintroduced "show_skolems" option by popular demand.
    83   - Renamed attribute: nitpick_def ~> nitpick_unfold.
    84     INCOMPATIBILITY.
    85 
    86 * Sledgehammer:
    87   - sledgehammer available_provers ~> sledgehammer supported_provers.
    88     INCOMPATIBILITY.
    89   - Added support for SNARK and ToFoF-E on SystemOnTPTP and for simply typed
    90     TPTP problems (TFF).
    91   - Added "preplay_timeout", "slicing", "type_enc", "sound", "max_mono_iters",
    92     and "max_new_mono_instances" options.
    93   - Removed "explicit_apply" and "full_types" options as well as "Full Types"
    94     Proof General menu item. INCOMPATIBILITY.
    95 
    96 * Metis:
    97   - Removed "metisF" -- use "metis" instead. INCOMPATIBILITY.
    98   - Obsoleted "metisFT" -- use "metis (full_types)" instead. INCOMPATIBILITY.
    99 
   100 * "try":
   101   - Renamed "try_methods" and added "simp:", "intro:", "dest:", and "elim:"
   102     options. INCOMPATIBILITY.
   103   - Introduced "try" that not only runs "try_methods" but also "solve_direct",
   104     "sledgehammer", "quickcheck", and "nitpick".
   105 
   106 * Quickcheck:
   107   - Added "eval" option to evaluate terms for the found counterexample
   108     (currently only supported by the default (exhaustive) tester)
   109   - Added post-processing of terms to obtain readable counterexamples
   110     (currently only supported by the default (exhaustive) tester)
   111   - New counterexample generator quickcheck[narrowing] enables
   112     narrowing-based testing.
   113     It requires that the Glasgow Haskell compiler is installed and
   114     its location is known to Isabelle with the environment variable
   115     ISABELLE_GHC.
   116 
   117 * Function package: discontinued option "tailrec".
   118 INCOMPATIBILITY. Use partial_function instead.
   119 
   120 * HOL-Probability:
   121   - Caratheodory's extension lemma is now proved for ring_of_sets.
   122   - Infinite products of probability measures are now available.
   123   - Use extended reals instead of positive extended reals.
   124     INCOMPATIBILITY.
   125 
   126 
   127 *** Document preparation ***
   128 
   129 * Discontinued special treatment of hard tabulators, which are better
   130 avoided in the first place.  Implicit tab-width is 1.
   131 
   132 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
   133 isar-ref manual.
   134 
   135 * Antiquotation @{value} evaluates the given term and presents its result.
   136 
   137 * Localized \isabellestyle switch can be used within blocks or groups
   138 like this:
   139 
   140   \isabellestyle{it}  %preferred default
   141   {\isabellestylett @{text "typewriter stuff"}}
   142 
   143 * New term style "isub" as ad-hoc conversion of variables x1, y23 into
   144 subscripted form x\<^isub>1, y\<^isub>2\<^isub>3.
   145 
   146 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
   147 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
   148 
   149 
   150 *** ML ***
   151 
   152 * The inner syntax of sort/type/term/prop supports inlined YXML
   153 representations within quoted string tokens.  By encoding logical
   154 entities via Term_XML (in ML or Scala) concrete syntax can be
   155 bypassed, which is particularly useful for producing bits of text
   156 under external program control.
   157 
   158 * Antiquotations for ML and document preparation are managed as theory
   159 data, which requires explicit setup.
   160 
   161 * Isabelle_Process.is_active allows tools to check if the official
   162 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
   163 (better known as Proof General).
   164 
   165 * Structure Proof_Context follows standard naming scheme.  Old
   166 ProofContext is still available for some time as legacy alias.
   167 
   168 * Structure Timing provides various operations for timing; supersedes
   169 former start_timing/end_timing etc.
   170 
   171 * Path.print is the official way to show file-system paths to users
   172 (including quotes etc.).
   173 
   174 * Inner syntax: identifiers in parse trees of generic categories
   175 "logic", "aprop", "idt" etc. carry position information (disguised as
   176 type constraints).  Occasional INCOMPATIBILITY with non-compliant
   177 translations that choke on unexpected type constraints.  Positions can
   178 be stripped in ML translations via Syntax.strip_positions /
   179 Syntax.strip_positions_ast, or via the syntax constant
   180 "_strip_positions" within parse trees.  As last resort, positions can
   181 be disabled via the configuration option Syntax.positions, which is
   182 called "syntax_positions" in Isar attribute syntax.
   183 
   184 * Discontinued special status of various ML structures that contribute
   185 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
   186 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
   187 refer directly to Ast.Constant, Lexicon.is_identifier,
   188 Syntax_Trans.mk_binder_tr etc.
   189 
   190 * Typed print translation: discontinued show_sorts argument, which is
   191 already available via context of "advanced" translation.
   192 
   193 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
   194 goal states; body tactic needs to address all subgoals uniformly.
   195 
   196 * Slightly more special eq_list/eq_set, with shortcut involving
   197 pointer equality (assumes that eq relation is reflexive).
   198 
   199 * Classical tactics use proper Proof.context instead of historic types
   200 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
   201 operate directly on Proof.context.  Raw type claset retains its use as
   202 snapshot of the classical context, which can be recovered via
   203 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
   204 INCOMPATIBILITY, classical tactics and derived proof methods require
   205 proper Proof.context.
   206 
   207 
   208 
   209 New in Isabelle2011 (January 2011)
   210 ----------------------------------
   211 
   212 *** General ***
   213 
   214 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
   215 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
   216 useful tooltips and hyperlinks produced from its static analysis.  The
   217 bundled component provides an executable Isabelle tool that can be run
   218 like this:
   219 
   220   Isabelle2011/bin/isabelle jedit
   221 
   222 * Significantly improved Isabelle/Isar implementation manual.
   223 
   224 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
   225 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
   226 while the default heap location within that directory lacks that extra
   227 suffix.  This isolates multiple Isabelle installations from each
   228 other, avoiding problems with old settings in new versions.
   229 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
   230 
   231 * Source files are always encoded as UTF-8, instead of old-fashioned
   232 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   233 the following package declarations:
   234 
   235   \usepackage[utf8]{inputenc}
   236   \usepackage{textcomp}
   237 
   238 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   239 a Unicode character is treated as a single symbol, not a sequence of
   240 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   241 contain symbols without further backslash escapes, Unicode can now be
   242 used here as well.  Recall that Symbol.explode in ML provides a
   243 consistent view on symbols, while raw explode (or String.explode)
   244 merely give a byte-oriented representation.
   245 
   246 * Theory loader: source files are primarily located via the master
   247 directory of each theory node (where the .thy file itself resides).
   248 The global load path is still partially available as legacy feature.
   249 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   250 explicit paths, relatively to the theory.
   251 
   252 * Special treatment of ML file names has been discontinued.
   253 Historically, optional extensions .ML or .sml were added on demand --
   254 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   255 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   256 
   257 * Various options that affect pretty printing etc. are now properly
   258 handled within the context via configuration options, instead of
   259 unsynchronized references or print modes.  There are both ML Config.T
   260 entities and Isar declaration attributes to access these.
   261 
   262   ML (Config.T)                 Isar (attribute)
   263 
   264   eta_contract                  eta_contract
   265   show_brackets                 show_brackets
   266   show_sorts                    show_sorts
   267   show_types                    show_types
   268   show_question_marks           show_question_marks
   269   show_consts                   show_consts
   270   show_abbrevs                  show_abbrevs
   271 
   272   Syntax.ast_trace              syntax_ast_trace
   273   Syntax.ast_stat               syntax_ast_stat
   274   Syntax.ambiguity_level        syntax_ambiguity_level
   275 
   276   Goal_Display.goals_limit      goals_limit
   277   Goal_Display.show_main_goal   show_main_goal
   278 
   279   Method.rule_trace             rule_trace
   280 
   281   Thy_Output.display            thy_output_display
   282   Thy_Output.quotes             thy_output_quotes
   283   Thy_Output.indent             thy_output_indent
   284   Thy_Output.source             thy_output_source
   285   Thy_Output.break              thy_output_break
   286 
   287 Note that corresponding "..._default" references in ML may only be
   288 changed globally at the ROOT session setup, but *not* within a theory.
   289 The option "show_abbrevs" supersedes the former print mode
   290 "no_abbrevs" with inverted meaning.
   291 
   292 * More systematic naming of some configuration options.
   293 INCOMPATIBILITY.
   294 
   295   trace_simp  ~>  simp_trace
   296   debug_simp  ~>  simp_debug
   297 
   298 * Support for real valued configuration options, using simplistic
   299 floating-point notation that coincides with the inner syntax for
   300 float_token.
   301 
   302 * Support for real valued preferences (with approximative PGIP type):
   303 front-ends need to accept "pgint" values in float notation.
   304 INCOMPATIBILITY.
   305 
   306 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   307 DejaVu Sans.
   308 
   309 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   310 
   311 
   312 *** Pure ***
   313 
   314 * Command 'type_synonym' (with single argument) replaces somewhat
   315 outdated 'types', which is still available as legacy feature for some
   316 time.
   317 
   318 * Command 'nonterminal' (with 'and' separated list of arguments)
   319 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   320 
   321 * Command 'notepad' replaces former 'example_proof' for
   322 experimentation in Isar without any result.  INCOMPATIBILITY.
   323 
   324 * Locale interpretation commands 'interpret' and 'sublocale' accept
   325 lists of equations to map definitions in a locale to appropriate
   326 entities in the context of the interpretation.  The 'interpretation'
   327 command already provided this functionality.
   328 
   329 * Diagnostic command 'print_dependencies' prints the locale instances
   330 that would be activated if the specified expression was interpreted in
   331 the current context.  Variant "print_dependencies!" assumes a context
   332 without interpretations.
   333 
   334 * Diagnostic command 'print_interps' prints interpretations in proofs
   335 in addition to interpretations in theories.
   336 
   337 * Discontinued obsolete 'global' and 'local' commands to manipulate
   338 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   339 Sign.root_path and Sign.local_path may be applied directly where this
   340 feature is still required for historical reasons.
   341 
   342 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   343 'definition' instead.
   344 
   345 * The "prems" fact, which refers to the accidental collection of
   346 foundational premises in the context, is now explicitly marked as
   347 legacy feature and will be discontinued soon.  Consider using "assms"
   348 of the head statement or reference facts by explicit names.
   349 
   350 * Document antiquotations @{class} and @{type} print classes and type
   351 constructors.
   352 
   353 * Document antiquotation @{file} checks file/directory entries within
   354 the local file system.
   355 
   356 
   357 *** HOL ***
   358 
   359 * Coercive subtyping: functions can be declared as coercions and type
   360 inference will add them as necessary upon input of a term.  Theory
   361 Complex_Main declares real :: nat => real and real :: int => real as
   362 coercions. A coercion function f is declared like this:
   363 
   364   declare [[coercion f]]
   365 
   366 To lift coercions through type constructors (e.g. from nat => real to
   367 nat list => real list), map functions can be declared, e.g.
   368 
   369   declare [[coercion_map map]]
   370 
   371 Currently coercion inference is activated only in theories including
   372 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   373 the configuration option "coercion_enabled", e.g. it can be enabled in
   374 other theories like this:
   375 
   376   declare [[coercion_enabled]]
   377 
   378 * Command 'partial_function' provides basic support for recursive
   379 function definitions over complete partial orders.  Concrete instances
   380 are provided for i) the option type, ii) tail recursion on arbitrary
   381 types, and iii) the heap monad of Imperative_HOL.  See
   382 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   383 for examples.
   384 
   385 * Function package: f.psimps rules are no longer implicitly declared
   386 as [simp].  INCOMPATIBILITY.
   387 
   388 * Datatype package: theorems generated for executable equality (class
   389 "eq") carry proper names and are treated as default code equations.
   390 
   391 * Inductive package: now offers command 'inductive_simps' to
   392 automatically derive instantiated and simplified equations for
   393 inductive predicates, similar to 'inductive_cases'.
   394 
   395 * Command 'enriched_type' allows to register properties of the
   396 functorial structure of types.
   397 
   398 * Improved infrastructure for term evaluation using code generator
   399 techniques, in particular static evaluation conversions.
   400 
   401 * Code generator: Scala (2.8 or higher) has been added to the target
   402 languages.
   403 
   404 * Code generator: globbing constant expressions "*" and "Theory.*"
   405 have been replaced by the more idiomatic "_" and "Theory._".
   406 INCOMPATIBILITY.
   407 
   408 * Code generator: export_code without explicit file declaration prints
   409 to standard output.  INCOMPATIBILITY.
   410 
   411 * Code generator: do not print function definitions for case
   412 combinators any longer.
   413 
   414 * Code generator: simplification with rules determined with
   415 src/Tools/Code/code_simp.ML and method "code_simp".
   416 
   417 * Code generator for records: more idiomatic representation of record
   418 types.  Warning: records are not covered by ancient SML code
   419 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   420 rep_datatype declaration helps to succeed then:
   421 
   422   record 'a foo = ...
   423   ...
   424   rep_datatype foo_ext ...
   425 
   426 * Records: logical foundation type for records does not carry a
   427 '_type' suffix any longer (obsolete due to authentic syntax).
   428 INCOMPATIBILITY.
   429 
   430 * Quickcheck now by default uses exhaustive testing instead of random
   431 testing.  Random testing can be invoked by "quickcheck [random]",
   432 exhaustive testing by "quickcheck [exhaustive]".
   433 
   434 * Quickcheck instantiates polymorphic types with small finite
   435 datatypes by default. This enables a simple execution mechanism to
   436 handle quantifiers and function equality over the finite datatypes.
   437 
   438 * Quickcheck random generator has been renamed from "code" to
   439 "random".  INCOMPATIBILITY.
   440 
   441 * Quickcheck now has a configurable time limit which is set to 30
   442 seconds by default. This can be changed by adding [timeout = n] to the
   443 quickcheck command. The time limit for Auto Quickcheck is still set
   444 independently.
   445 
   446 * Quickcheck in locales considers interpretations of that locale for
   447 counter example search.
   448 
   449 * Sledgehammer:
   450   - Added "smt" and "remote_smt" provers based on the "smt" proof
   451     method. See the Sledgehammer manual for details ("isabelle doc
   452     sledgehammer").
   453   - Renamed commands:
   454     sledgehammer atp_info ~> sledgehammer running_provers
   455     sledgehammer atp_kill ~> sledgehammer kill_provers
   456     sledgehammer available_atps ~> sledgehammer available_provers
   457     INCOMPATIBILITY.
   458   - Renamed options:
   459     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   460     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   461     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   462     (and "ms" and "min" are no longer supported)
   463     INCOMPATIBILITY.
   464 
   465 * Nitpick:
   466   - Renamed options:
   467     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   468     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   469     INCOMPATIBILITY.
   470   - Added support for partial quotient types.
   471   - Added local versions of the "Nitpick.register_xxx" functions.
   472   - Added "whack" option.
   473   - Allow registration of quotient types as codatatypes.
   474   - Improved "merge_type_vars" option to merge more types.
   475   - Removed unsound "fast_descrs" option.
   476   - Added custom symmetry breaking for datatypes, making it possible to reach
   477     higher cardinalities.
   478   - Prevent the expansion of too large definitions.
   479 
   480 * Proof methods "metis" and "meson" now have configuration options
   481 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   482 to diagnose these tools. E.g.
   483 
   484     using [[metis_trace = true]]
   485 
   486 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   487 manually as command 'solve_direct'.
   488 
   489 * The default SMT solver Z3 must be enabled explicitly (due to
   490 licensing issues) by setting the environment variable
   491 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   492 commercial applications, the SMT solver CVC3 is provided as fall-back;
   493 changing the SMT solver is done via the configuration option
   494 "smt_solver".
   495 
   496 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   497 i.e. "remote_cvc3" and "remote_z3".
   498 
   499 * Added basic SMT support for datatypes, records, and typedefs using
   500 the oracle mode (no proofs).  Direct support of pairs has been dropped
   501 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   502 support for a similar behavior).  Minor INCOMPATIBILITY.
   503 
   504 * Changed SMT configuration options:
   505   - Renamed:
   506     z3_proofs ~> smt_oracle (with inverted meaning)
   507     z3_trace_assms ~> smt_trace_used_facts
   508     INCOMPATIBILITY.
   509   - Added:
   510     smt_verbose
   511     smt_random_seed
   512     smt_datatypes
   513     smt_infer_triggers
   514     smt_monomorph_limit
   515     cvc3_options
   516     remote_cvc3_options
   517     remote_z3_options
   518     yices_options
   519 
   520 * Boogie output files (.b2i files) need to be declared in the theory
   521 header.
   522 
   523 * Simplification procedure "list_to_set_comprehension" rewrites list
   524 comprehensions applied to List.set to set comprehensions.  Occasional
   525 INCOMPATIBILITY, may be deactivated like this:
   526 
   527   declare [[simproc del: list_to_set_comprehension]]
   528 
   529 * Removed old version of primrec package.  INCOMPATIBILITY.
   530 
   531 * Removed simplifier congruence rule of "prod_case", as has for long
   532 been the case with "split".  INCOMPATIBILITY.
   533 
   534 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   535 
   536 * Removed [split_format ... and ... and ...] version of
   537 [split_format].  Potential INCOMPATIBILITY.
   538 
   539 * Predicate "sorted" now defined inductively, with nice induction
   540 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   541 
   542 * Constant "contents" renamed to "the_elem", to free the generic name
   543 contents for other uses.  INCOMPATIBILITY.
   544 
   545 * Renamed class eq and constant eq (for code generation) to class
   546 equal and constant equal, plus renaming of related facts and various
   547 tuning.  INCOMPATIBILITY.
   548 
   549 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   550 
   551 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   552 INCOMPATIBILITY.
   553 
   554 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   555 avoid confusion with finite sets.  INCOMPATIBILITY.
   556 
   557 * Abandoned locales equiv, congruent and congruent2 for equivalence
   558 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   559 for congruent(2)).
   560 
   561 * Some previously unqualified names have been qualified:
   562 
   563   types
   564     bool ~> HOL.bool
   565     nat ~> Nat.nat
   566 
   567   constants
   568     Trueprop ~> HOL.Trueprop
   569     True ~> HOL.True
   570     False ~> HOL.False
   571     op & ~> HOL.conj
   572     op | ~> HOL.disj
   573     op --> ~> HOL.implies
   574     op = ~> HOL.eq
   575     Not ~> HOL.Not
   576     The ~> HOL.The
   577     All ~> HOL.All
   578     Ex ~> HOL.Ex
   579     Ex1 ~> HOL.Ex1
   580     Let ~> HOL.Let
   581     If ~> HOL.If
   582     Ball ~> Set.Ball
   583     Bex ~> Set.Bex
   584     Suc ~> Nat.Suc
   585     Pair ~> Product_Type.Pair
   586     fst ~> Product_Type.fst
   587     snd ~> Product_Type.snd
   588     curry ~> Product_Type.curry
   589     op : ~> Set.member
   590     Collect ~> Set.Collect
   591 
   592 INCOMPATIBILITY.
   593 
   594 * More canonical naming convention for some fundamental definitions:
   595 
   596     bot_bool_eq ~> bot_bool_def
   597     top_bool_eq ~> top_bool_def
   598     inf_bool_eq ~> inf_bool_def
   599     sup_bool_eq ~> sup_bool_def
   600     bot_fun_eq  ~> bot_fun_def
   601     top_fun_eq  ~> top_fun_def
   602     inf_fun_eq  ~> inf_fun_def
   603     sup_fun_eq  ~> sup_fun_def
   604 
   605 INCOMPATIBILITY.
   606 
   607 * More stylized fact names:
   608 
   609   expand_fun_eq ~> fun_eq_iff
   610   expand_set_eq ~> set_eq_iff
   611   set_ext       ~> set_eqI
   612   nat_number    ~> eval_nat_numeral
   613 
   614 INCOMPATIBILITY.
   615 
   616 * Refactoring of code-generation specific operations in theory List:
   617 
   618   constants
   619     null ~> List.null
   620 
   621   facts
   622     mem_iff ~> member_def
   623     null_empty ~> null_def
   624 
   625 INCOMPATIBILITY.  Note that these were not supposed to be used
   626 regularly unless for striking reasons; their main purpose was code
   627 generation.
   628 
   629 Various operations from the Haskell prelude are used for generating
   630 Haskell code.
   631 
   632 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   633 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   634 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   635 
   636 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   637 "*" and "+" respectively.  INCOMPATIBILITY.
   638 
   639 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   640 "Sum_Type.Plus" instead.
   641 
   642 * Constant "split" has been merged with constant "prod_case"; names of
   643 ML functions, facts etc. involving split have been retained so far,
   644 though.  INCOMPATIBILITY.
   645 
   646 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   647 instead.  INCOMPATIBILITY.
   648 
   649 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   650 INCOMPATIBILITY.
   651 
   652 * Former theory Library/Enum is now part of the HOL-Main image.
   653 INCOMPATIBILITY: all constants of the Enum theory now have to be
   654 referred to by its qualified name.
   655 
   656   enum    ~>  Enum.enum
   657   nlists  ~>  Enum.nlists
   658   product ~>  Enum.product
   659 
   660 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   661 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   662 INCOMPATIBILITY.
   663 
   664 * Theory Library/SetsAndFunctions has been split into
   665 Library/Function_Algebras and Library/Set_Algebras; canonical names
   666 for instance definitions for functions; various improvements.
   667 INCOMPATIBILITY.
   668 
   669 * Theory Library/Multiset provides stable quicksort implementation of
   670 sort_key.
   671 
   672 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   673 INCOMPATIBILITY.
   674 
   675 * Session Multivariate_Analysis: introduced a type class for euclidean
   676 space.  Most theorems are now stated in terms of euclidean spaces
   677 instead of finite cartesian products.
   678 
   679   types
   680     real ^ 'n ~>  'a::real_vector
   681               ~>  'a::euclidean_space
   682               ~>  'a::ordered_euclidean_space
   683         (depends on your needs)
   684 
   685   constants
   686      _ $ _        ~> _ $$ _
   687      \<chi> x. _  ~> \<chi>\<chi> x. _
   688      CARD('n)     ~> DIM('a)
   689 
   690 Also note that the indices are now natural numbers and not from some
   691 finite type. Finite cartesian products of euclidean spaces, products
   692 of euclidean spaces the real and complex numbers are instantiated to
   693 be euclidean_spaces.  INCOMPATIBILITY.
   694 
   695 * Session Probability: introduced pextreal as positive extended real
   696 numbers.  Use pextreal as value for measures.  Introduce the
   697 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   698 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   699 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   700 
   701 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   702 INCOMPATIBILITY.
   703 
   704 * Session SPARK (with image HOL-SPARK) provides commands to load and
   705 prove verification conditions generated by the SPARK Ada program
   706 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   707 
   708 
   709 *** HOL-Algebra ***
   710 
   711 * Theorems for additive ring operations (locale abelian_monoid and
   712 descendants) are generated by interpretation from their multiplicative
   713 counterparts.  Names (in particular theorem names) have the mandatory
   714 qualifier 'add'.  Previous theorem names are redeclared for
   715 compatibility.
   716 
   717 * Structure "int_ring" is now an abbreviation (previously a
   718 definition).  This fits more natural with advanced interpretations.
   719 
   720 
   721 *** HOLCF ***
   722 
   723 * The domain package now runs in definitional mode by default: The
   724 former command 'new_domain' is now called 'domain'.  To use the domain
   725 package in its original axiomatic mode, use 'domain (unsafe)'.
   726 INCOMPATIBILITY.
   727 
   728 * The new class "domain" is now the default sort.  Class "predomain"
   729 is an unpointed version of "domain". Theories can be updated by
   730 replacing sort annotations as shown below.  INCOMPATIBILITY.
   731 
   732   'a::type ~> 'a::countable
   733   'a::cpo  ~> 'a::predomain
   734   'a::pcpo ~> 'a::domain
   735 
   736 * The old type class "rep" has been superseded by class "domain".
   737 Accordingly, users of the definitional package must remove any
   738 "default_sort rep" declarations.  INCOMPATIBILITY.
   739 
   740 * The domain package (definitional mode) now supports unpointed
   741 predomain argument types, as long as they are marked 'lazy'. (Strict
   742 arguments must be in class "domain".) For example, the following
   743 domain definition now works:
   744 
   745   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   746 
   747 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   748 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   749 'a option, and 'a list.  Additionally, it configures fixrec and the
   750 domain package to work with these types.  For example:
   751 
   752   fixrec isInl :: "('a + 'b) u -> tr"
   753     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   754 
   755   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   756 
   757 * The "(permissive)" option of fixrec has been replaced with a
   758 per-equation "(unchecked)" option. See
   759 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
   760 
   761 * The "bifinite" class no longer fixes a constant "approx"; the class
   762 now just asserts that such a function exists.  INCOMPATIBILITY.
   763 
   764 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
   765 defines an embedding of type 'a defl into udom by default; instances
   766 of "bifinite" and "domain" classes are available in
   767 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
   768 
   769 * The syntax "REP('a)" has been replaced with "DEFL('a)".
   770 
   771 * The predicate "directed" has been removed.  INCOMPATIBILITY.
   772 
   773 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
   774 
   775 * The function "cprod_map" has been renamed to "prod_map".
   776 INCOMPATIBILITY.
   777 
   778 * The monadic bind operator on each powerdomain has new binder syntax
   779 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
   780 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
   781 
   782 * The infix syntax for binary union on each powerdomain has changed
   783 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
   784 syntax.  INCOMPATIBILITY.
   785 
   786 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
   787 still supported as an input translation.
   788 
   789 * Renamed some theorems (the original names are also still available).
   790 
   791   expand_fun_below   ~> fun_below_iff
   792   below_fun_ext      ~> fun_belowI
   793   expand_cfun_eq     ~> cfun_eq_iff
   794   ext_cfun           ~> cfun_eqI
   795   expand_cfun_below  ~> cfun_below_iff
   796   below_cfun_ext     ~> cfun_belowI
   797   cont2cont_Rep_CFun ~> cont2cont_APP
   798 
   799 * The Abs and Rep functions for various types have changed names.
   800 Related theorem names have also changed to match. INCOMPATIBILITY.
   801 
   802   Rep_CFun  ~> Rep_cfun
   803   Abs_CFun  ~> Abs_cfun
   804   Rep_Sprod ~> Rep_sprod
   805   Abs_Sprod ~> Abs_sprod
   806   Rep_Ssum  ~> Rep_ssum
   807   Abs_Ssum  ~> Abs_ssum
   808 
   809 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   810 been renamed to *_bottom_iff.  INCOMPATIBILITY.
   811 
   812 * Various changes to bisimulation/coinduction with domain package:
   813 
   814   - Definitions of "bisim" constants no longer mention definedness.
   815   - With mutual recursion, "bisim" predicate is now curried.
   816   - With mutual recursion, each type gets a separate coind theorem.
   817   - Variable names in bisim_def and coinduct rules have changed.
   818 
   819 INCOMPATIBILITY.
   820 
   821 * Case combinators generated by the domain package for type "foo" are
   822 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
   823 
   824 * Several theorems have been renamed to more accurately reflect the
   825 names of constants and types involved.  INCOMPATIBILITY.
   826 
   827   thelub_const    ~> lub_const
   828   lub_const       ~> is_lub_const
   829   thelubI         ~> lub_eqI
   830   is_lub_lub      ~> is_lubD2
   831   lubI            ~> is_lub_lub
   832   unique_lub      ~> is_lub_unique
   833   is_ub_lub       ~> is_lub_rangeD1
   834   lub_bin_chain   ~> is_lub_bin_chain
   835   lub_fun         ~> is_lub_fun
   836   thelub_fun      ~> lub_fun
   837   thelub_cfun     ~> lub_cfun
   838   thelub_Pair     ~> lub_Pair
   839   lub_cprod       ~> is_lub_prod
   840   thelub_cprod    ~> lub_prod
   841   minimal_cprod   ~> minimal_prod
   842   inst_cprod_pcpo ~> inst_prod_pcpo
   843   UU_I            ~> bottomI
   844   compact_UU      ~> compact_bottom
   845   deflation_UU    ~> deflation_bottom
   846   finite_deflation_UU ~> finite_deflation_bottom
   847 
   848 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
   849 
   850   sq_ord_less_eq_trans ~> below_eq_trans
   851   sq_ord_eq_less_trans ~> eq_below_trans
   852   refl_less            ~> below_refl
   853   trans_less           ~> below_trans
   854   antisym_less         ~> below_antisym
   855   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
   856   box_less             ~> box_below
   857   rev_trans_less       ~> rev_below_trans
   858   not_less2not_eq      ~> not_below2not_eq
   859   less_UU_iff          ~> below_UU_iff
   860   flat_less_iff        ~> flat_below_iff
   861   adm_less             ~> adm_below
   862   adm_not_less         ~> adm_not_below
   863   adm_compact_not_less ~> adm_compact_not_below
   864   less_fun_def         ~> below_fun_def
   865   expand_fun_less      ~> fun_below_iff
   866   less_fun_ext         ~> fun_belowI
   867   less_discr_def       ~> below_discr_def
   868   discr_less_eq        ~> discr_below_eq
   869   less_unit_def        ~> below_unit_def
   870   less_cprod_def       ~> below_prod_def
   871   prod_lessI           ~> prod_belowI
   872   Pair_less_iff        ~> Pair_below_iff
   873   fst_less_iff         ~> fst_below_iff
   874   snd_less_iff         ~> snd_below_iff
   875   expand_cfun_less     ~> cfun_below_iff
   876   less_cfun_ext        ~> cfun_belowI
   877   injection_less       ~> injection_below
   878   less_up_def          ~> below_up_def
   879   not_Iup_less         ~> not_Iup_below
   880   Iup_less             ~> Iup_below
   881   up_less              ~> up_below
   882   Def_inject_less_eq   ~> Def_below_Def
   883   Def_less_is_eq       ~> Def_below_iff
   884   spair_less_iff       ~> spair_below_iff
   885   less_sprod           ~> below_sprod
   886   spair_less           ~> spair_below
   887   sfst_less_iff        ~> sfst_below_iff
   888   ssnd_less_iff        ~> ssnd_below_iff
   889   fix_least_less       ~> fix_least_below
   890   dist_less_one        ~> dist_below_one
   891   less_ONE             ~> below_ONE
   892   ONE_less_iff         ~> ONE_below_iff
   893   less_sinlD           ~> below_sinlD
   894   less_sinrD           ~> below_sinrD
   895 
   896 
   897 *** FOL and ZF ***
   898 
   899 * All constant names are now qualified internally and use proper
   900 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
   901 
   902 
   903 *** ML ***
   904 
   905 * Antiquotation @{assert} inlines a function bool -> unit that raises
   906 Fail if the argument is false.  Due to inlining the source position of
   907 failed assertions is included in the error output.
   908 
   909 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
   910 text is in practice always evaluated with a stable theory checkpoint.
   911 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
   912 
   913 * Antiquotation @{theory A} refers to theory A from the ancestry of
   914 the current context, not any accidental theory loader state as before.
   915 Potential INCOMPATIBILITY, subtle change in semantics.
   916 
   917 * Syntax.pretty_priority (default 0) configures the required priority
   918 of pretty-printed output and thus affects insertion of parentheses.
   919 
   920 * Syntax.default_root (default "any") configures the inner syntax
   921 category (nonterminal symbol) for parsing of terms.
   922 
   923 * Former exception Library.UnequalLengths now coincides with
   924 ListPair.UnequalLengths.
   925 
   926 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
   927 main functionality is provided by structure Simplifier.
   928 
   929 * Renamed raw "explode" function to "raw_explode" to emphasize its
   930 meaning.  Note that internally to Isabelle, Symbol.explode is used in
   931 almost all situations.
   932 
   933 * Discontinued obsolete function sys_error and exception SYS_ERROR.
   934 See implementation manual for further details on exceptions in
   935 Isabelle/ML.
   936 
   937 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   938 meaning.
   939 
   940 * Renamed structure PureThy to Pure_Thy and moved most of its
   941 operations to structure Global_Theory, to emphasize that this is
   942 rarely-used global-only stuff.
   943 
   944 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
   945 instead (or tracing for high-volume output).
   946 
   947 * Configuration option show_question_marks only affects regular pretty
   948 printing of types and terms, not raw Term.string_of_vname.
   949 
   950 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
   951 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
   952 @{thms} for most purposes.
   953 
   954 * ML structure Unsynchronized is never opened, not even in Isar
   955 interaction mode as before.  Old Unsynchronized.set etc. have been
   956 discontinued -- use plain := instead.  This should be *rare* anyway,
   957 since modern tools always work via official context data, notably
   958 configuration options.
   959 
   960 * Parallel and asynchronous execution requires special care concerning
   961 interrupts.  Structure Exn provides some convenience functions that
   962 avoid working directly with raw Interrupt.  User code must not absorb
   963 interrupts -- intermediate handling (for cleanup etc.) needs to be
   964 followed by re-raising of the original exception.  Another common
   965 source of mistakes are "handle _" patterns, which make the meaning of
   966 the program subject to physical effects of the environment.
   967 
   968 
   969 
   970 New in Isabelle2009-2 (June 2010)
   971 ---------------------------------
   972 
   973 *** General ***
   974 
   975 * Authentic syntax for *all* logical entities (type classes, type
   976 constructors, term constants): provides simple and robust
   977 correspondence between formal entities and concrete syntax.  Within
   978 the parse tree / AST representations, "constants" are decorated by
   979 their category (class, type, const) and spelled out explicitly with
   980 their full internal name.
   981 
   982 Substantial INCOMPATIBILITY concerning low-level syntax declarations
   983 and translations (translation rules and translation functions in ML).
   984 Some hints on upgrading:
   985 
   986   - Many existing uses of 'syntax' and 'translations' can be replaced
   987     by more modern 'type_notation', 'notation' and 'abbreviation',
   988     which are independent of this issue.
   989 
   990   - 'translations' require markup within the AST; the term syntax
   991     provides the following special forms:
   992 
   993       CONST c   -- produces syntax version of constant c from context
   994       XCONST c  -- literally c, checked as constant from context
   995       c         -- literally c, if declared by 'syntax'
   996 
   997     Plain identifiers are treated as AST variables -- occasionally the
   998     system indicates accidental variables via the error "rhs contains
   999     extra variables".
  1000 
  1001     Type classes and type constructors are marked according to their
  1002     concrete syntax.  Some old translations rules need to be written
  1003     for the "type" category, using type constructor application
  1004     instead of pseudo-term application of the default category
  1005     "logic".
  1006 
  1007   - 'parse_translation' etc. in ML may use the following
  1008     antiquotations:
  1009 
  1010       @{class_syntax c}   -- type class c within parse tree / AST
  1011       @{term_syntax c}    -- type constructor c within parse tree / AST
  1012       @{const_syntax c}   -- ML version of "CONST c" above
  1013       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
  1014 
  1015   - Literal types within 'typed_print_translations', i.e. those *not*
  1016     represented as pseudo-terms are represented verbatim.  Use @{class
  1017     c} or @{type_name c} here instead of the above syntax
  1018     antiquotations.
  1019 
  1020 Note that old non-authentic syntax was based on unqualified base
  1021 names, so all of the above "constant" names would coincide.  Recall
  1022 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
  1023 diagnose syntax problems.
  1024 
  1025 * Type constructors admit general mixfix syntax, not just infix.
  1026 
  1027 * Concrete syntax may be attached to local entities without a proof
  1028 body, too.  This works via regular mixfix annotations for 'fix',
  1029 'def', 'obtain' etc. or via the explicit 'write' command, which is
  1030 similar to the 'notation' command in theory specifications.
  1031 
  1032 * Discontinued unnamed infix syntax (legacy feature for many years) --
  1033 need to specify constant name and syntax separately.  Internal ML
  1034 datatype constructors have been renamed from InfixName to Infix etc.
  1035 Minor INCOMPATIBILITY.
  1036 
  1037 * Schematic theorem statements need to be explicitly markup as such,
  1038 via commands 'schematic_lemma', 'schematic_theorem',
  1039 'schematic_corollary'.  Thus the relevance of the proof is made
  1040 syntactically clear, which impacts performance in a parallel or
  1041 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  1042 
  1043 * Use of cumulative prems via "!" in some proof methods has been
  1044 discontinued (old legacy feature).
  1045 
  1046 * References 'trace_simp' and 'debug_simp' have been replaced by
  1047 configuration options stored in the context. Enabling tracing (the
  1048 case of debugging is similar) in proofs works via
  1049 
  1050   using [[trace_simp = true]]
  1051 
  1052 Tracing is then active for all invocations of the simplifier in
  1053 subsequent goal refinement steps. Tracing may also still be enabled or
  1054 disabled via the ProofGeneral settings menu.
  1055 
  1056 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  1057 'hide_fact' replace the former 'hide' KIND command.  Minor
  1058 INCOMPATIBILITY.
  1059 
  1060 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  1061 more efficient than combinations with -q1 or -q2.
  1062 
  1063 
  1064 *** Pure ***
  1065 
  1066 * Proofterms record type-class reasoning explicitly, using the
  1067 "unconstrain" operation internally.  This eliminates all sort
  1068 constraints from a theorem and proof, introducing explicit
  1069 OFCLASS-premises.  On the proof term level, this operation is
  1070 automatically applied at theorem boundaries, such that closed proofs
  1071 are always free of sort constraints.  INCOMPATIBILITY for tools that
  1072 inspect proof terms.
  1073 
  1074 * Local theory specifications may depend on extra type variables that
  1075 are not present in the result type -- arguments TYPE('a) :: 'a itself
  1076 are added internally.  For example:
  1077 
  1078   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  1079 
  1080 * Predicates of locales introduced by classes carry a mandatory
  1081 "class" prefix.  INCOMPATIBILITY.
  1082 
  1083 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  1084 
  1085 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  1086 'class' instead.
  1087 
  1088 * Command 'code_reflect' allows to incorporate generated ML code into
  1089 runtime environment; replaces immature code_datatype antiquotation.
  1090 INCOMPATIBILITY.
  1091 
  1092 * Code generator: simple concept for abstract datatypes obeying
  1093 invariants.
  1094 
  1095 * Code generator: details of internal data cache have no impact on the
  1096 user space functionality any longer.
  1097 
  1098 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1099 subgoals.  This is more appropriate for interpretations with 'where'.
  1100 INCOMPATIBILITY.
  1101 
  1102 * Command 'example_proof' opens an empty proof body.  This allows to
  1103 experiment with Isar, without producing any persistent result.
  1104 
  1105 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1106 within a local theory context, with explicit checking of the
  1107 constructors involved (in contrast to the raw 'syntax' versions).
  1108 
  1109 * Commands 'types' and 'typedecl' now work within a local theory
  1110 context -- without introducing dependencies on parameters or
  1111 assumptions, which is not possible in Isabelle/Pure.
  1112 
  1113 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1114 within a local theory context.  Minor INCOMPATIBILITY.
  1115 
  1116 
  1117 *** HOL ***
  1118 
  1119 * Command 'typedef' now works within a local theory context -- without
  1120 introducing dependencies on parameters or assumptions, which is not
  1121 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1122 contain multiple interpretations of local typedefs (with different
  1123 non-emptiness proofs), even in a global theory context.
  1124 
  1125 * New package for quotient types.  Commands 'quotient_type' and
  1126 'quotient_definition' may be used for defining types and constants by
  1127 quotient constructions.  An example is the type of integers created by
  1128 quotienting pairs of natural numbers:
  1129 
  1130   fun
  1131     intrel :: "(nat * nat) => (nat * nat) => bool"
  1132   where
  1133     "intrel (x, y) (u, v) = (x + v = u + y)"
  1134 
  1135   quotient_type int = "nat * nat" / intrel
  1136     by (auto simp add: equivp_def expand_fun_eq)
  1137 
  1138   quotient_definition
  1139     "0::int" is "(0::nat, 0::nat)"
  1140 
  1141 The method "lifting" can be used to lift of theorems from the
  1142 underlying "raw" type to the quotient type.  The example
  1143 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1144 construction and provides a reasoning infrastructure for finite sets.
  1145 
  1146 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1147 clash with new theory Quotient in Main HOL.
  1148 
  1149 * Moved the SMT binding into the main HOL session, eliminating
  1150 separate HOL-SMT session.
  1151 
  1152 * List membership infix mem operation is only an input abbreviation.
  1153 INCOMPATIBILITY.
  1154 
  1155 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1156 for future developements; former Library/Word.thy is still present in
  1157 the AFP entry RSAPPS.
  1158 
  1159 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1160 longer shadowed.  INCOMPATIBILITY.
  1161 
  1162 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1163 INCOMPATIBILITY.
  1164 
  1165 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1166 INCOMPATIBILITY.
  1167 
  1168 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1169 instead.  INCOMPATIBILITY.
  1170 
  1171 * Dropped several real-specific versions of lemmas about floor and
  1172 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1173 instead.  INCOMPATIBILITY.
  1174 
  1175   floor_number_of_eq         ~> floor_number_of
  1176   le_floor_eq_number_of      ~> number_of_le_floor
  1177   le_floor_eq_zero           ~> zero_le_floor
  1178   le_floor_eq_one            ~> one_le_floor
  1179   floor_less_eq_number_of    ~> floor_less_number_of
  1180   floor_less_eq_zero         ~> floor_less_zero
  1181   floor_less_eq_one          ~> floor_less_one
  1182   less_floor_eq_number_of    ~> number_of_less_floor
  1183   less_floor_eq_zero         ~> zero_less_floor
  1184   less_floor_eq_one          ~> one_less_floor
  1185   floor_le_eq_number_of      ~> floor_le_number_of
  1186   floor_le_eq_zero           ~> floor_le_zero
  1187   floor_le_eq_one            ~> floor_le_one
  1188   floor_subtract_number_of   ~> floor_diff_number_of
  1189   floor_subtract_one         ~> floor_diff_one
  1190   ceiling_number_of_eq       ~> ceiling_number_of
  1191   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1192   ceiling_le_zero_eq         ~> ceiling_le_zero
  1193   ceiling_le_eq_one          ~> ceiling_le_one
  1194   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1195   less_ceiling_eq_zero       ~> zero_less_ceiling
  1196   less_ceiling_eq_one        ~> one_less_ceiling
  1197   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1198   ceiling_less_eq_zero       ~> ceiling_less_zero
  1199   ceiling_less_eq_one        ~> ceiling_less_one
  1200   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1201   le_ceiling_eq_zero         ~> zero_le_ceiling
  1202   le_ceiling_eq_one          ~> one_le_ceiling
  1203   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1204   ceiling_subtract_one       ~> ceiling_diff_one
  1205 
  1206 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1207 application of the various fold combinators on finite sets.
  1208 
  1209 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1210 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1211 implementation.  INCOMPATIBILTY.
  1212 
  1213 * Theory Library/Coinductive_List has been removed -- superseded by
  1214 AFP/thys/Coinductive.
  1215 
  1216 * Theory PReal, including the type "preal" and related operations, has
  1217 been removed.  INCOMPATIBILITY.
  1218 
  1219 * Real: new development using Cauchy Sequences.
  1220 
  1221 * Split off theory "Big_Operators" containing setsum, setprod,
  1222 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1223 
  1224 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1225 "Int" etc.  INCOMPATIBILITY.
  1226 
  1227 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1228 
  1229 * New set of rules "ac_simps" provides combined assoc / commute
  1230 rewrites for all interpretations of the appropriate generic locales.
  1231 
  1232 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1233 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1234 appropriate and more consistent names suitable for name prefixes
  1235 within the HOL theories.  INCOMPATIBILITY.
  1236 
  1237 * Some generic constants have been put to appropriate theories:
  1238   - less_eq, less: Orderings
  1239   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1240   - inverse, divide: Rings
  1241 INCOMPATIBILITY.
  1242 
  1243 * More consistent naming of type classes involving orderings (and
  1244 lattices):
  1245 
  1246     lower_semilattice                   ~> semilattice_inf
  1247     upper_semilattice                   ~> semilattice_sup
  1248 
  1249     dense_linear_order                  ~> dense_linorder
  1250 
  1251     pordered_ab_group_add               ~> ordered_ab_group_add
  1252     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1253     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1254     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1255     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1256     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1257     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1258     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1259     pordered_comm_ring                  ~> ordered_comm_ring
  1260     pordered_comm_semiring              ~> ordered_comm_semiring
  1261     pordered_ring                       ~> ordered_ring
  1262     pordered_ring_abs                   ~> ordered_ring_abs
  1263     pordered_semiring                   ~> ordered_semiring
  1264 
  1265     ordered_ab_group_add                ~> linordered_ab_group_add
  1266     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1267     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1268     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1269     ordered_field                       ~> linordered_field
  1270     ordered_field_no_lb                 ~> linordered_field_no_lb
  1271     ordered_field_no_ub                 ~> linordered_field_no_ub
  1272     ordered_field_dense_linear_order    ~> dense_linordered_field
  1273     ordered_idom                        ~> linordered_idom
  1274     ordered_ring                        ~> linordered_ring
  1275     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1276     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1277     ordered_ring_strict                 ~> linordered_ring_strict
  1278     ordered_semidom                     ~> linordered_semidom
  1279     ordered_semiring                    ~> linordered_semiring
  1280     ordered_semiring_1                  ~> linordered_semiring_1
  1281     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1282     ordered_semiring_strict             ~> linordered_semiring_strict
  1283 
  1284   The following slightly odd type classes have been moved to a
  1285   separate theory Library/Lattice_Algebras:
  1286 
  1287     lordered_ab_group_add               ~> lattice_ab_group_add
  1288     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1289     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1290     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1291     lordered_ring                       ~> lattice_ring
  1292 
  1293 INCOMPATIBILITY.
  1294 
  1295 * Refined field classes:
  1296   - classes division_ring_inverse_zero, field_inverse_zero,
  1297     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1298     subsumes former division_by_zero class;
  1299   - numerous lemmas have been ported from field to division_ring.
  1300 INCOMPATIBILITY.
  1301 
  1302 * Refined algebra theorem collections:
  1303   - dropped theorem group group_simps, use algebra_simps instead;
  1304   - dropped theorem group ring_simps, use field_simps instead;
  1305   - proper theorem collection field_simps subsumes former theorem
  1306     groups field_eq_simps and field_simps;
  1307   - dropped lemma eq_minus_self_iff which is a duplicate for
  1308     equal_neg_zero.
  1309 INCOMPATIBILITY.
  1310 
  1311 * Theory Finite_Set and List: some lemmas have been generalized from
  1312 sets to lattices:
  1313 
  1314   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1315   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1316   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1317   union_Union_fold_union        ~> sup_Sup_fold_sup
  1318   Inter_fold_inter              ~> Inf_fold_inf
  1319   Union_fold_union              ~> Sup_fold_sup
  1320   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1321   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1322   INTER_fold_inter              ~> INFI_fold_inf
  1323   UNION_fold_union              ~> SUPR_fold_sup
  1324 
  1325 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1326 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1327 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1328 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1329 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1330 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1331 
  1332 * Reorganized theory Multiset: swapped notation of pointwise and
  1333 multiset order:
  1334 
  1335   - pointwise ordering is instance of class order with standard syntax
  1336     <= and <;
  1337   - multiset ordering has syntax <=# and <#; partial order properties
  1338     are provided by means of interpretation with prefix
  1339     multiset_order;
  1340   - less duplication, less historical organization of sections,
  1341     conversion from associations lists to multisets, rudimentary code
  1342     generation;
  1343   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1344     if needed.
  1345 
  1346 Renamed:
  1347 
  1348   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1349   multi_count_ext  ~>  multiset_ext
  1350   diff_union_inverse2  ~>  diff_union_cancelR
  1351 
  1352 INCOMPATIBILITY.
  1353 
  1354 * Theory Permutation: replaced local "remove" by List.remove1.
  1355 
  1356 * Code generation: ML and OCaml code is decorated with signatures.
  1357 
  1358 * Theory List: added transpose.
  1359 
  1360 * Library/Nat_Bijection.thy is a collection of bijective functions
  1361 between nat and other types, which supersedes the older libraries
  1362 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1363 
  1364   Constants:
  1365   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1366   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1367   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1368   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1369   Countable.pair_encode           ~> prod_encode
  1370   NatIso.prod2nat                 ~> prod_encode
  1371   NatIso.nat2prod                 ~> prod_decode
  1372   NatIso.sum2nat                  ~> sum_encode
  1373   NatIso.nat2sum                  ~> sum_decode
  1374   NatIso.list2nat                 ~> list_encode
  1375   NatIso.nat2list                 ~> list_decode
  1376   NatIso.set2nat                  ~> set_encode
  1377   NatIso.nat2set                  ~> set_decode
  1378 
  1379   Lemmas:
  1380   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1381   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1382   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1383   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1384   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1385   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1386   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1387   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1388   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1389   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1390   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1391   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1392   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1393 
  1394 * Sledgehammer:
  1395   - Renamed ATP commands:
  1396     atp_info     ~> sledgehammer running_atps
  1397     atp_kill     ~> sledgehammer kill_atps
  1398     atp_messages ~> sledgehammer messages
  1399     atp_minimize ~> sledgehammer minimize
  1400     print_atps   ~> sledgehammer available_atps
  1401     INCOMPATIBILITY.
  1402   - Added user's manual ("isabelle doc sledgehammer").
  1403   - Added option syntax and "sledgehammer_params" to customize
  1404     Sledgehammer's behavior.  See the manual for details.
  1405   - Modified the Isar proof reconstruction code so that it produces
  1406     direct proofs rather than proofs by contradiction.  (This feature
  1407     is still experimental.)
  1408   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1409     full-typed mode.
  1410   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1411 
  1412 * Nitpick:
  1413   - Added and implemented "binary_ints" and "bits" options.
  1414   - Added "std" option and implemented support for nonstandard models.
  1415   - Added and implemented "finitize" option to improve the precision
  1416     of infinite datatypes based on a monotonicity analysis.
  1417   - Added support for quotient types.
  1418   - Added support for "specification" and "ax_specification"
  1419     constructs.
  1420   - Added support for local definitions (for "function" and
  1421     "termination" proofs).
  1422   - Added support for term postprocessors.
  1423   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1424   - Improved efficiency of "destroy_constrs" optimization.
  1425   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1426     record getters.
  1427   - Fixed soundness bug related to higher-order constructors.
  1428   - Fixed soundness bug when "full_descrs" is enabled.
  1429   - Improved precision of set constructs.
  1430   - Added "atoms" option.
  1431   - Added cache to speed up repeated Kodkod invocations on the same
  1432     problems.
  1433   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1434     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1435     "SAT4J_Light".  INCOMPATIBILITY.
  1436   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1437     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1438   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1439 
  1440 * Method "induct" now takes instantiations of the form t, where t is not
  1441   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1442   If this is not intended, t has to be enclosed in parentheses.
  1443   By default, the equalities generated by definitional instantiations
  1444   are pre-simplified, which may cause parameters of inductive cases
  1445   to disappear, or may even delete some of the inductive cases.
  1446   Use "induct (no_simp)" instead of "induct" to restore the old
  1447   behaviour. The (no_simp) option is also understood by the "cases"
  1448   and "nominal_induct" methods, which now perform pre-simplification, too.
  1449   INCOMPATIBILITY.
  1450 
  1451 
  1452 *** HOLCF ***
  1453 
  1454 * Variable names in lemmas generated by the domain package have
  1455 changed; the naming scheme is now consistent with the HOL datatype
  1456 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1457 
  1458 * The domain package no longer defines the function "foo_copy" for
  1459 recursive domain "foo".  The reach lemma is now stated directly in
  1460 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1461 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1462 
  1463 * Most definedness lemmas generated by the domain package (previously
  1464 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1465 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1466 Proofs that used definedness lemmas as intro rules may break,
  1467 potential INCOMPATIBILITY.
  1468 
  1469 * Induction and casedist rules generated by the domain package now
  1470 declare proper case_names (one called "bottom", and one named for each
  1471 constructor).  INCOMPATIBILITY.
  1472 
  1473 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1474 rules are generated for each domain, INCOMPATIBILITY.
  1475 
  1476   foo_bar.reach       ~> foo.reach  bar.reach
  1477   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1478 
  1479 * Some lemmas generated by the domain package have been renamed for
  1480 consistency with the datatype package, INCOMPATIBILITY.
  1481 
  1482   foo.ind        ~> foo.induct
  1483   foo.finite_ind ~> foo.finite_induct
  1484   foo.coind      ~> foo.coinduct
  1485   foo.casedist   ~> foo.exhaust
  1486   foo.exhaust    ~> foo.nchotomy
  1487 
  1488 * For consistency with other definition packages, the fixrec package
  1489 now generates qualified theorem names, INCOMPATIBILITY.
  1490 
  1491   foo_simps  ~> foo.simps
  1492   foo_unfold ~> foo.unfold
  1493   foo_induct ~> foo.induct
  1494 
  1495 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1496 method and internal fixrec proofs now use the default simpset instead.
  1497 INCOMPATIBILITY.
  1498 
  1499 * The "contlub" predicate has been removed.  Proof scripts should use
  1500 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1501 
  1502 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1503 
  1504 * The constants cpair, cfst, and csnd have been removed in favor of
  1505 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1506 
  1507 
  1508 *** ML ***
  1509 
  1510 * Antiquotations for basic formal entities:
  1511 
  1512     @{class NAME}         -- type class
  1513     @{class_syntax NAME}  -- syntax representation of the above
  1514 
  1515     @{type_name NAME}     -- logical type
  1516     @{type_abbrev NAME}   -- type abbreviation
  1517     @{nonterminal NAME}   -- type of concrete syntactic category
  1518     @{type_syntax NAME}   -- syntax representation of any of the above
  1519 
  1520     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1521     @{const_abbrev NAME}  -- abbreviated constant
  1522     @{const_syntax NAME}  -- syntax representation of any of the above
  1523 
  1524 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1525 syntax constant (cf. 'syntax' command).
  1526 
  1527 * Antiquotation @{make_string} inlines a function to print arbitrary
  1528 values similar to the ML toplevel.  The result is compiler dependent
  1529 and may fall back on "?" in certain situations.
  1530 
  1531 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1532 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1533 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1534 not work with the asynchronous Isar document model.
  1535 
  1536 * Configuration options now admit dynamic default values, depending on
  1537 the context or even global references.
  1538 
  1539 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1540 uses an efficient external library if available (for Poly/ML).
  1541 
  1542 * Renamed some important ML structures, while keeping the old names
  1543 for some time as aliases within the structure Legacy:
  1544 
  1545   OuterKeyword  ~>  Keyword
  1546   OuterLex      ~>  Token
  1547   OuterParse    ~>  Parse
  1548   OuterSyntax   ~>  Outer_Syntax
  1549   PrintMode     ~>  Print_Mode
  1550   SpecParse     ~>  Parse_Spec
  1551   ThyInfo       ~>  Thy_Info
  1552   ThyLoad       ~>  Thy_Load
  1553   ThyOutput     ~>  Thy_Output
  1554   TypeInfer     ~>  Type_Infer
  1555 
  1556 Note that "open Legacy" simplifies porting of sources, but forgetting
  1557 to remove it again will complicate porting again in the future.
  1558 
  1559 * Most operations that refer to a global context are named
  1560 accordingly, e.g. Simplifier.global_context or
  1561 ProofContext.init_global.  There are some situations where a global
  1562 context actually works, but under normal circumstances one needs to
  1563 pass the proper local context through the code!
  1564 
  1565 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1566 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1567 Pretty.pp argument to merge, which is absent in the standard
  1568 Theory_Data version.
  1569 
  1570 * Sorts.certify_sort and derived "cert" operations for types and terms
  1571 no longer minimize sorts.  Thus certification at the boundary of the
  1572 inference kernel becomes invariant under addition of class relations,
  1573 which is an important monotonicity principle.  Sorts are now minimized
  1574 in the syntax layer only, at the boundary between the end-user and the
  1575 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1576 explicitly in rare situations.
  1577 
  1578 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1579 emphasize that this is in no way a standard operation.
  1580 INCOMPATIBILITY.
  1581 
  1582 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1583 usual for resolution.  Rare INCOMPATIBILITY.
  1584 
  1585 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1586 to emphasize that these only work in a global situation (which is
  1587 quite rare).
  1588 
  1589 * Curried take and drop in library.ML; negative length is interpreted
  1590 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1591 
  1592 * Proof terms: type substitutions on proof constants now use canonical
  1593 order of type variables.  INCOMPATIBILITY for tools working with proof
  1594 terms.
  1595 
  1596 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1597 may no longer carry premises.  User-level specifications are
  1598 transformed accordingly by Thm.add_axiom/add_def.
  1599 
  1600 
  1601 *** System ***
  1602 
  1603 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1604 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1605 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1606 
  1607 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1608 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1609 respectively.
  1610 
  1611 * Old lib/scripts/polyml-platform is superseded by the
  1612 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1613 variant, even on a 64 bit machine.  The following example setting
  1614 prefers 64 bit if available:
  1615 
  1616   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1617 
  1618 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1619 Isabelle/Scala layer for advanced prover interaction and integration.
  1620 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1621 component.
  1622 
  1623 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1624 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1625 similar to the default assignment of the document preparation system
  1626 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1627 provides some operations for direct access to the font without asking
  1628 the user for manual installation.
  1629 
  1630 
  1631 
  1632 New in Isabelle2009-1 (December 2009)
  1633 -------------------------------------
  1634 
  1635 *** General ***
  1636 
  1637 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1638 one backslash should be used, even in ML sources.
  1639 
  1640 
  1641 *** Pure ***
  1642 
  1643 * Locale interpretation propagates mixins along the locale hierarchy.
  1644 The currently only available mixins are the equations used to map
  1645 local definitions to terms of the target domain of an interpretation.
  1646 
  1647 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1648 loc" to print all interpretations of locale "loc" in the theory.
  1649 Interpretations in proofs are not shown.
  1650 
  1651 * Thoroughly revised locales tutorial.  New section on conditional
  1652 interpretation.
  1653 
  1654 * On instantiation of classes, remaining undefined class parameters
  1655 are formally declared.  INCOMPATIBILITY.
  1656 
  1657 
  1658 *** Document preparation ***
  1659 
  1660 * New generalized style concept for printing terms: @{foo (style) ...}
  1661 instead of @{foo_style style ...}  (old form is still retained for
  1662 backward compatibility).  Styles can be also applied for
  1663 antiquotations prop, term_type and typeof.
  1664 
  1665 
  1666 *** HOL ***
  1667 
  1668 * New proof method "smt" for a combination of first-order logic with
  1669 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1670 fixed-size bitvectors; there is also basic support for higher-order
  1671 features (esp. lambda abstractions).  It is an incomplete decision
  1672 procedure based on external SMT solvers using the oracle mechanism;
  1673 for the SMT solver Z3, this method is proof-producing.  Certificates
  1674 are provided to avoid calling the external solvers solely for
  1675 re-checking proofs.  Due to a remote SMT service there is no need for
  1676 installing SMT solvers locally.  See src/HOL/SMT.
  1677 
  1678 * New commands to load and prove verification conditions generated by
  1679 the Boogie program verifier or derived systems (e.g. the Verifying C
  1680 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1681 
  1682 * New counterexample generator tool 'nitpick' based on the Kodkod
  1683 relational model finder.  See src/HOL/Tools/Nitpick and
  1684 src/HOL/Nitpick_Examples.
  1685 
  1686 * New commands 'code_pred' and 'values' to invoke the predicate
  1687 compiler and to enumerate values of inductive predicates.
  1688 
  1689 * A tabled implementation of the reflexive transitive closure.
  1690 
  1691 * New implementation of quickcheck uses generic code generator;
  1692 default generators are provided for all suitable HOL types, records
  1693 and datatypes.  Old quickcheck can be re-activated importing theory
  1694 Library/SML_Quickcheck.
  1695 
  1696 * New testing tool Mirabelle for automated proof tools.  Applies
  1697 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1698 every proof step in a theory.  To be used in batch mode via the
  1699 "mirabelle" utility.
  1700 
  1701 * New proof method "sos" (sum of squares) for nonlinear real
  1702 arithmetic (originally due to John Harison). It requires theory
  1703 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1704 works well in practice on quantifier-free real arithmetic with +, -,
  1705 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1706 inequalities between polynomials.  It makes use of external
  1707 semidefinite programming solvers.  Method "sos" generates a
  1708 certificate that can be pasted into the proof thus avoiding the need
  1709 to call an external tool every time the proof is checked.  See
  1710 src/HOL/Library/Sum_Of_Squares.
  1711 
  1712 * New method "linarith" invokes existing linear arithmetic decision
  1713 procedure only.
  1714 
  1715 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1716 
  1717 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1718 Causes full type information to be output to the ATPs.  This slows
  1719 ATPs down considerably but eliminates a source of unsound "proofs"
  1720 that fail later.
  1721 
  1722 * New method "metisFT": A version of metis that uses full type
  1723 information in order to avoid failures of proof reconstruction.
  1724 
  1725 * New evaluator "approximate" approximates an real valued term using
  1726 the same method as the approximation method.
  1727 
  1728 * Method "approximate" now supports arithmetic expressions as
  1729 boundaries of intervals and implements interval splitting and Taylor
  1730 series expansion.
  1731 
  1732 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1733 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1734 
  1735 * New theory SupInf of the supremum and infimum operators for sets of
  1736 reals.
  1737 
  1738 * New theory Probability, which contains a development of measure
  1739 theory, eventually leading to Lebesgue integration and probability.
  1740 
  1741 * Extended Multivariate Analysis to include derivation and Brouwer's
  1742 fixpoint theorem.
  1743 
  1744 * Reorganization of number theory, INCOMPATIBILITY:
  1745   - new number theory development for nat and int, in theories Divides
  1746     and GCD as well as in new session Number_Theory
  1747   - some constants and facts now suffixed with _nat and _int
  1748     accordingly
  1749   - former session NumberTheory now named Old_Number_Theory, including
  1750     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1751   - moved theory Pocklington from src/HOL/Library to
  1752     src/HOL/Old_Number_Theory
  1753 
  1754 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1755 lcm of finite and infinite sets. It is shown that they form a complete
  1756 lattice.
  1757 
  1758 * Class semiring_div requires superclass no_zero_divisors and proof of
  1759 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1760 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1761 generalized to class semiring_div, subsuming former theorems
  1762 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1763 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1764 INCOMPATIBILITY.
  1765 
  1766 * Refinements to lattice classes and sets:
  1767   - less default intro/elim rules in locale variant, more default
  1768     intro/elim rules in class variant: more uniformity
  1769   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1770     le_inf_iff
  1771   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1772     sup_aci)
  1773   - renamed ACI to inf_sup_aci
  1774   - new class "boolean_algebra"
  1775   - class "complete_lattice" moved to separate theory
  1776     "Complete_Lattice"; corresponding constants (and abbreviations)
  1777     renamed and with authentic syntax:
  1778     Set.Inf ~>    Complete_Lattice.Inf
  1779     Set.Sup ~>    Complete_Lattice.Sup
  1780     Set.INFI ~>   Complete_Lattice.INFI
  1781     Set.SUPR ~>   Complete_Lattice.SUPR
  1782     Set.Inter ~>  Complete_Lattice.Inter
  1783     Set.Union ~>  Complete_Lattice.Union
  1784     Set.INTER ~>  Complete_Lattice.INTER
  1785     Set.UNION ~>  Complete_Lattice.UNION
  1786   - authentic syntax for
  1787     Set.Pow
  1788     Set.image
  1789   - mere abbreviations:
  1790     Set.empty               (for bot)
  1791     Set.UNIV                (for top)
  1792     Set.inter               (for inf, formerly Set.Int)
  1793     Set.union               (for sup, formerly Set.Un)
  1794     Complete_Lattice.Inter  (for Inf)
  1795     Complete_Lattice.Union  (for Sup)
  1796     Complete_Lattice.INTER  (for INFI)
  1797     Complete_Lattice.UNION  (for SUPR)
  1798   - object-logic definitions as far as appropriate
  1799 
  1800 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1801 Un_subset_iff are explicitly deleted as default simp rules; then also
  1802 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1803 deleted to achieve the desired effect.
  1804 
  1805 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1806 rules by default any longer; the same applies to min_max.inf_absorb1
  1807 etc.  INCOMPATIBILITY.
  1808 
  1809 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1810 pred_set_conv by default.  INCOMPATIBILITY.
  1811 
  1812 * Power operations on relations and functions are now one dedicated
  1813 constant "compow" with infix syntax "^^".  Power operation on
  1814 multiplicative monoids retains syntax "^" and is now defined generic
  1815 in class power.  INCOMPATIBILITY.
  1816 
  1817 * Relation composition "R O S" now has a more standard argument order:
  1818 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1819 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1820 break, since the O_assoc rule was not rewritten like this.  Fix using
  1821 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1822 
  1823 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1824 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1825 INCOMPATIBILITY.
  1826 
  1827 * Most rules produced by inductive and datatype package have mandatory
  1828 prefixes.  INCOMPATIBILITY.
  1829 
  1830 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1831 the attribute of the same name.  Each of the theorems in the list
  1832 DERIV_intros assumes composition with an additional function and
  1833 matches a variable to the derivative, which has to be solved by the
  1834 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1835 of most elementary terms.  Former Maclauren.DERIV_tac and
  1836 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1837 INCOMPATIBILITY.
  1838 
  1839 * Code generator attributes follow the usual underscore convention:
  1840     code_unfold     replaces    code unfold
  1841     code_post       replaces    code post
  1842     etc.
  1843   INCOMPATIBILITY.
  1844 
  1845 * Renamed methods:
  1846     sizechange -> size_change
  1847     induct_scheme -> induction_schema
  1848   INCOMPATIBILITY.
  1849 
  1850 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1851 INCOMPATIBILITY, use "undefined" directly.
  1852 
  1853 * Renamed theorems:
  1854     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1855     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1856     Suc_plus1 -> Suc_eq_plus1
  1857     *anti_sym -> *antisym*
  1858     vector_less_eq_def -> vector_le_def
  1859   INCOMPATIBILITY.
  1860 
  1861 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1862 INCOMPATIBILITY.
  1863 
  1864 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1865 INCOMPATIBILITY.
  1866 
  1867 
  1868 *** HOLCF ***
  1869 
  1870 * Theory Representable defines a class "rep" of domains that are
  1871 representable (via an ep-pair) in the universal domain type "udom".
  1872 Instances are provided for all type constructors defined in HOLCF.
  1873 
  1874 * The 'new_domain' command is a purely definitional version of the
  1875 domain package, for representable domains.  Syntax is identical to the
  1876 old domain package.  The 'new_domain' package also supports indirect
  1877 recursion using previously-defined type constructors.  See
  1878 src/HOLCF/ex/New_Domain.thy for examples.
  1879 
  1880 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1881 on the left-hand side of an equation, and then performs
  1882 simplification.  Rewriting is done using rules declared with the
  1883 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1884 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1885 
  1886 * The pattern-match compiler in 'fixrec' can now handle constructors
  1887 with HOL function types.  Pattern-match combinators for the Pair
  1888 constructor are pre-configured.
  1889 
  1890 * The 'fixrec' package now produces better fixed-point induction rules
  1891 for mutually-recursive definitions:  Induction rules have conclusions
  1892 of the form "P foo bar" instead of "P <foo, bar>".
  1893 
  1894 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1895 been renamed to "below".  The name "below" now replaces "less" in many
  1896 theorem names.  (Legacy theorem names using "less" are still supported
  1897 as well.)
  1898 
  1899 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1900 patterns can be used to generate strictness rules, or to make
  1901 functions more strict (much like the bang-patterns supported by the
  1902 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1903 examples.
  1904 
  1905 
  1906 *** ML ***
  1907 
  1908 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1909 errors and run-time exceptions, including detailed source positions.
  1910 
  1911 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1912 identified entries, with some additional information such as source
  1913 position, logical grouping etc.
  1914 
  1915 * Theory and context data is now introduced by the simplified and
  1916 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1917 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1918 copy operation) is still available for some time.
  1919 
  1920 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1921 provides a high-level programming interface to synchronized state
  1922 variables with atomic update.  This works via pure function
  1923 application within a critical section -- its runtime should be as
  1924 short as possible; beware of deadlocks if critical code is nested,
  1925 either directly or indirectly via other synchronized variables!
  1926 
  1927 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1928 wraps raw ML references, explicitly indicating their non-thread-safe
  1929 behaviour.  The Isar toplevel keeps this structure open, to
  1930 accommodate Proof General as well as quick and dirty interactive
  1931 experiments with references.
  1932 
  1933 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1934 parallel tactical reasoning.
  1935 
  1936 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1937 are similar to SUBPROOF, but are slightly more flexible: only the
  1938 specified parts of the subgoal are imported into the context, and the
  1939 body tactic may introduce new subgoals and schematic variables.
  1940 
  1941 * Old tactical METAHYPS, which does not observe the proof context, has
  1942 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1943 or Subgoal.FOCUS etc.
  1944 
  1945 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1946 functors have their own ML name space there is no point to mark them
  1947 separately.)  Minor INCOMPATIBILITY.
  1948 
  1949 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1950 
  1951 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1952 INCOMPATIBILITY.
  1953 
  1954 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1955 mode, which avoids critical setmp.
  1956 
  1957 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1958 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1959 Attrib/Method.setup introduced in Isabelle2009.
  1960 
  1961 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1962 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1963 last resort.  INCOMPATIBILITY.
  1964 
  1965 * Display.pretty_thm now requires a proper context (cf. former
  1966 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1967 or even Display.pretty_thm_without_context as last resort.
  1968 INCOMPATIBILITY.
  1969 
  1970 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1971 Syntax.pretty_typ/term directly, preferably with proper context
  1972 instead of global theory.
  1973 
  1974 
  1975 *** System ***
  1976 
  1977 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1978 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1979 usedir option -q.
  1980 
  1981 * Support for additional "Isabelle components" via etc/components, see
  1982 also the system manual.
  1983 
  1984 * The isabelle makeall tool now operates on all components with
  1985 IsaMakefile, not just hardwired "logics".
  1986 
  1987 * Removed "compress" option from isabelle-process and isabelle usedir;
  1988 this is always enabled.
  1989 
  1990 * Discontinued support for Poly/ML 4.x versions.
  1991 
  1992 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  1993 on a given logic image.  This requires the lighttpd webserver and is
  1994 currently supported on Linux only.
  1995 
  1996 
  1997 
  1998 New in Isabelle2009 (April 2009)
  1999 --------------------------------
  2000 
  2001 *** General ***
  2002 
  2003 * Simplified main Isabelle executables, with less surprises on
  2004 case-insensitive file-systems (such as Mac OS).
  2005 
  2006   - The main Isabelle tool wrapper is now called "isabelle" instead of
  2007     "isatool."
  2008 
  2009   - The former "isabelle" alias for "isabelle-process" has been
  2010     removed (should rarely occur to regular users).
  2011 
  2012   - The former "isabelle-interface" and its alias "Isabelle" have been
  2013     removed (interfaces are now regular Isabelle tools).
  2014 
  2015 Within scripts and make files, the Isabelle environment variables
  2016 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  2017 respectively.  (The latter are still available as legacy feature.)
  2018 
  2019 The old isabelle-interface wrapper could react in confusing ways if
  2020 the interface was uninstalled or changed otherwise.  Individual
  2021 interface tool configuration is now more explicit, see also the
  2022 Isabelle system manual.  In particular, Proof General is now available
  2023 via "isabelle emacs".
  2024 
  2025 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  2026 purge installed copies of Isabelle executables and re-run "isabelle
  2027 install -p ...", or use symlinks.
  2028 
  2029 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  2030 old ~/isabelle, which was slightly non-standard and apt to cause
  2031 surprises on case-insensitive file-systems (such as Mac OS).
  2032 
  2033 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  2034 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  2035 care is required when using older releases of Isabelle.  Note that
  2036 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  2037 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  2038 
  2039 * Proofs of fully specified statements are run in parallel on
  2040 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  2041 a regular 4-core machine, if the initial heap space is made reasonably
  2042 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  2043 
  2044 * The main reference manuals ("isar-ref", "implementation", and
  2045 "system") have been updated and extended.  Formally checked references
  2046 as hyperlinks are now available uniformly.
  2047 
  2048 
  2049 *** Pure ***
  2050 
  2051 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  2052 respects.  The most important changes are listed below.  See the
  2053 Tutorial on Locales ("locales" manual) for details.
  2054 
  2055 - In locale expressions, instantiation replaces renaming.  Parameters
  2056 must be declared in a for clause.  To aid compatibility with previous
  2057 parameter inheritance, in locale declarations, parameters that are not
  2058 'touched' (instantiation position "_" or omitted) are implicitly added
  2059 with their syntax at the beginning of the for clause.
  2060 
  2061 - Syntax from abbreviations and definitions in locales is available in
  2062 locale expressions and context elements.  The latter is particularly
  2063 useful in locale declarations.
  2064 
  2065 - More flexible mechanisms to qualify names generated by locale
  2066 expressions.  Qualifiers (prefixes) may be specified in locale
  2067 expressions, and can be marked as mandatory (syntax: "name!:") or
  2068 optional (syntax "name?:").  The default depends for plain "name:"
  2069 depends on the situation where a locale expression is used: in
  2070 commands 'locale' and 'sublocale' prefixes are optional, in
  2071 'interpretation' and 'interpret' prefixes are mandatory.  The old
  2072 implicit qualifiers derived from the parameter names of a locale are
  2073 no longer generated.
  2074 
  2075 - Command "sublocale l < e" replaces "interpretation l < e".  The
  2076 instantiation clause in "interpretation" and "interpret" (square
  2077 brackets) is no longer available.  Use locale expressions.
  2078 
  2079 - When converting proof scripts, mandatory qualifiers in
  2080 'interpretation' and 'interpret' should be retained by default, even
  2081 if this is an INCOMPATIBILITY compared to former behavior.  In the
  2082 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  2083 in locale expressions range over a single locale instance only.
  2084 
  2085 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  2086 In existing theorem specifications replace the includes element by the
  2087 respective context elements of the included locale, omitting those
  2088 that are already present in the theorem specification.  Multiple
  2089 assume elements of a locale should be replaced by a single one
  2090 involving the locale predicate.  In the proof body, declarations (most
  2091 notably theorems) may be regained by interpreting the respective
  2092 locales in the proof context as required (command "interpret").
  2093 
  2094 If using "includes" in replacement of a target solely because the
  2095 parameter types in the theorem are not as general as in the target,
  2096 consider declaring a new locale with additional type constraints on
  2097 the parameters (context element "constrains").
  2098 
  2099 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2100 
  2101 - Locale interpretation commands no longer attempt to simplify goal.
  2102 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2103 methods intro_locales and unfold_locales to clarify.
  2104 
  2105 - Locale interpretation commands no longer accept interpretation
  2106 attributes.  INCOMPATIBILITY.
  2107 
  2108 * Class declaration: so-called "base sort" must not be given in import
  2109 list any longer, but is inferred from the specification.  Particularly
  2110 in HOL, write
  2111 
  2112     class foo = ...
  2113 
  2114 instead of
  2115 
  2116     class foo = type + ...
  2117 
  2118 * Class target: global versions of theorems stemming do not carry a
  2119 parameter prefix any longer.  INCOMPATIBILITY.
  2120 
  2121 * Class 'instance' command no longer accepts attached definitions.
  2122 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2123 
  2124 * Recovered hiding of consts, which was accidentally broken in
  2125 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2126 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2127 
  2128 * Slightly more coherent Pure syntax, with updated documentation in
  2129 isar-ref manual.  Removed locales meta_term_syntax and
  2130 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2131 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2132 directly in regular applications.
  2133 
  2134 * There is a new syntactic category "float_const" for signed decimal
  2135 fractions (e.g. 123.45 or -123.45).
  2136 
  2137 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2138 interface with 'setup' command instead.
  2139 
  2140 * Command 'local_setup' is similar to 'setup', but operates on a local
  2141 theory context.
  2142 
  2143 * The 'axiomatization' command now only works within a global theory
  2144 context.  INCOMPATIBILITY.
  2145 
  2146 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2147 hypotheses.  Sorts required in the course of reasoning need to be
  2148 covered by the constraints in the initial statement, completed by the
  2149 type instance information of the background theory.  Non-trivial sort
  2150 hypotheses, which rarely occur in practice, may be specified via
  2151 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2152 
  2153   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2154 
  2155 The result contains an implicit sort hypotheses as before --
  2156 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2157 normalization.
  2158 
  2159 * Generalized Isar history, with support for linear undo, direct state
  2160 addressing etc.
  2161 
  2162 * Changed defaults for unify configuration options:
  2163 
  2164   unify_trace_bound = 50 (formerly 25)
  2165   unify_search_bound = 60 (formerly 30)
  2166 
  2167 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2168 
  2169   a) On theory merge, the last set of code equations for a particular
  2170      constant is taken (in accordance with the policy applied by other
  2171      parts of the code generator framework).
  2172 
  2173   b) Code equations stemming from explicit declarations (e.g. code
  2174      attribute) gain priority over default code equations stemming
  2175      from definition, primrec, fun etc.
  2176 
  2177 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2178 
  2179 * Unified theorem tables for both code generators.  Thus [code
  2180 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2181 
  2182 * Command 'find_consts' searches for constants based on type and name
  2183 patterns, e.g.
  2184 
  2185     find_consts "_ => bool"
  2186 
  2187 By default, matching is against subtypes, but it may be restricted to
  2188 the whole type.  Searching by name is possible.  Multiple queries are
  2189 conjunctive and queries may be negated by prefixing them with a
  2190 hyphen:
  2191 
  2192     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2193 
  2194 * New 'find_theorems' criterion "solves" matches theorems that
  2195 directly solve the current goal (modulo higher-order unification).
  2196 
  2197 * Auto solve feature for main theorem statements: whenever a new goal
  2198 is stated, "find_theorems solves" is called; any theorems that could
  2199 solve the lemma directly are listed as part of the goal state.
  2200 Cf. associated options in Proof General Isabelle settings menu,
  2201 enabled by default, with reasonable timeout for pathological cases of
  2202 higher-order unification.
  2203 
  2204 
  2205 *** Document preparation ***
  2206 
  2207 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2208 demanding keyword 'by' and supporting the full method expression
  2209 syntax just like the Isar command 'by'.
  2210 
  2211 
  2212 *** HOL ***
  2213 
  2214 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2215 points Main and Complex_Main remain as before.
  2216 
  2217 * Logic image HOL-Plain provides a minimal HOL with the most important
  2218 tools available (inductive, datatype, primrec, ...).  This facilitates
  2219 experimentation and tool development.  Note that user applications
  2220 (and library theories) should never refer to anything below theory
  2221 Main, as before.
  2222 
  2223 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2224 experimentation due to shorter build times.
  2225 
  2226 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2227 were previously part of former HOL-Complex.  Entry point Hyperreal
  2228 remains valid, but theories formerly using Complex_Main should now use
  2229 new entry point Hypercomplex.
  2230 
  2231 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2232 Posix processes.  Avoids potentially expensive forking of the ML
  2233 process.  New thread-based implementation also works on non-Unix
  2234 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2235 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2236 commands are covered in the isar-ref manual.
  2237 
  2238 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2239 sledgehammer without local ATP installation (Vampire etc.). Other
  2240 provers may be included via suitable ML wrappers, see also
  2241 src/HOL/ATP_Linkup.thy.
  2242 
  2243 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2244 menu.
  2245 
  2246 * The metis method no longer fails because the theorem is too trivial
  2247 (contains the empty clause).
  2248 
  2249 * The metis method now fails in the usual manner, rather than raising
  2250 an exception, if it determines that it cannot prove the theorem.
  2251 
  2252 * Method "coherent" implements a prover for coherent logic (see also
  2253 src/Tools/coherent.ML).
  2254 
  2255 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2256 "undefined" is the right choice to replace "arbitrary", though
  2257 logically there is no difference.  INCOMPATIBILITY.
  2258 
  2259 * Command "value" now integrates different evaluation mechanisms.  The
  2260 result of the first successful evaluation mechanism is printed.  In
  2261 square brackets a particular named evaluation mechanisms may be
  2262 specified (currently, [SML], [code] or [nbe]).  See further
  2263 src/HOL/ex/Eval_Examples.thy.
  2264 
  2265 * Normalization by evaluation now allows non-leftlinear equations.
  2266 Declare with attribute [code nbe].
  2267 
  2268 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2269 as the structured Isar versions "cases" and "induct", cf. the
  2270 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2271 are now presented as a list of individual projections
  2272 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2273 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2274 rare situations a different rule is selected --- notably nested tuple
  2275 elimination instead of former prod.exhaust: use explicit (case_tac t
  2276 rule: prod.exhaust) here.
  2277 
  2278 * Attributes "cases", "induct", "coinduct" support "del" option.
  2279 
  2280 * Removed fact "case_split_thm", which duplicates "case_split".
  2281 
  2282 * The option datatype has been moved to a new theory Option.  Renamed
  2283 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2284 
  2285 * New predicate "strict_mono" classifies strict functions on partial
  2286 orders.  With strict functions on linear orders, reasoning about
  2287 (in)equalities is facilitated by theorems "strict_mono_eq",
  2288 "strict_mono_less_eq" and "strict_mono_less".
  2289 
  2290 * Some set operations are now proper qualified constants with
  2291 authentic syntax.  INCOMPATIBILITY:
  2292 
  2293     op Int ~>   Set.Int
  2294     op Un ~>    Set.Un
  2295     INTER ~>    Set.INTER
  2296     UNION ~>    Set.UNION
  2297     Inter ~>    Set.Inter
  2298     Union ~>    Set.Union
  2299     {} ~>       Set.empty
  2300     UNIV ~>     Set.UNIV
  2301 
  2302 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2303 theory Set.
  2304 
  2305 * Auxiliary class "itself" has disappeared -- classes without any
  2306 parameter are treated as expected by the 'class' command.
  2307 
  2308 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2309 
  2310 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2311 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2312 
  2313 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2314 method "approximation".  It proves formulas on real values by using
  2315 interval arithmetic.  In the formulas are also the transcendental
  2316 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2317 allowed. For examples see
  2318 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2319 
  2320 * Theory "Reflection" now resides in HOL/Library.
  2321 
  2322 * Entry point to Word library now simply named "Word".
  2323 INCOMPATIBILITY.
  2324 
  2325 * Made source layout more coherent with logical distribution
  2326 structure:
  2327 
  2328     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2329     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2330     src/HOL/Library/GCD.thy ~> src/HOL/
  2331     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2332     src/HOL/Library/Parity.thy ~> src/HOL/
  2333     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2334     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2335     src/HOL/Real/Lubs.thy ~> src/HOL/
  2336     src/HOL/Real/PReal.thy ~> src/HOL/
  2337     src/HOL/Real/Rational.thy ~> src/HOL/
  2338     src/HOL/Real/RComplete.thy ~> src/HOL/
  2339     src/HOL/Real/RealDef.thy ~> src/HOL/
  2340     src/HOL/Real/RealPow.thy ~> src/HOL/
  2341     src/HOL/Real/Real.thy ~> src/HOL/
  2342     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2343     src/HOL/Complex/Complex.thy ~> src/HOL/
  2344     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2345     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2346     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2347     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2348     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2349     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2350     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2351     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2352     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2353     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2354     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2355     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2356     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2357     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2358     src/HOL/Real/Float ~> src/HOL/Library/
  2359     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2360     src/HOL/Real/RealVector.thy ~> src/HOL/
  2361 
  2362     src/HOL/arith_data.ML ~> src/HOL/Tools
  2363     src/HOL/hologic.ML ~> src/HOL/Tools
  2364     src/HOL/simpdata.ML ~> src/HOL/Tools
  2365     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2366     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2367     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2368     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2369     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2370     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2371     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2372 
  2373     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2374     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2375     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2376     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2377     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2378     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2379 
  2380 * If methods "eval" and "evaluation" encounter a structured proof
  2381 state with !!/==>, only the conclusion is evaluated to True (if
  2382 possible), avoiding strange error messages.
  2383 
  2384 * Method "sizechange" automates termination proofs using (a
  2385 modification of) the size-change principle.  Requires SAT solver.  See
  2386 src/HOL/ex/Termination.thy for examples.
  2387 
  2388 * Simplifier: simproc for let expressions now unfolds if bound
  2389 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2390 
  2391 * Method "arith": Linear arithmetic now ignores all inequalities when
  2392 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2393 
  2394 * New attribute "arith" for facts that should always be used
  2395 automatically by arithmetic. It is intended to be used locally in
  2396 proofs, e.g.
  2397 
  2398   assumes [arith]: "x > 0"
  2399 
  2400 Global usage is discouraged because of possible performance impact.
  2401 
  2402 * New classes "top" and "bot" with corresponding operations "top" and
  2403 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2404 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2405 
  2406 * Changed definition lemma "less_fun_def" in order to provide an
  2407 instance for preorders on functions; use lemma "less_le" instead.
  2408 INCOMPATIBILITY.
  2409 
  2410 * Theory Orderings: class "wellorder" moved here, with explicit
  2411 induction rule "less_induct" as assumption.  For instantiation of
  2412 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2413 INCOMPATIBILITY.
  2414 
  2415 * Theory Orderings: added class "preorder" as superclass of "order".
  2416 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2417 etc. slightly changed.  Some theorems named order_class.* now named
  2418 preorder_class.*.
  2419 
  2420 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2421 "diag" to "Id_on".
  2422 
  2423 * Theory Finite_Set: added a new fold combinator of type
  2424 
  2425   ('a => 'b => 'b) => 'b => 'a set => 'b
  2426 
  2427 Occasionally this is more convenient than the old fold combinator
  2428 which is now defined in terms of the new one and renamed to
  2429 fold_image.
  2430 
  2431 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2432 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2433 extended with further lemmas!).  At the moment both still exist but
  2434 the former will disappear at some point.
  2435 
  2436 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2437 class recpower.  Type-specific simp rules for various recpower types
  2438 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2439 
  2440 rat_power_0    -> power_0
  2441 rat_power_Suc  -> power_Suc
  2442 realpow_0      -> power_0
  2443 realpow_Suc    -> power_Suc
  2444 complexpow_0   -> power_0
  2445 complexpow_Suc -> power_Suc
  2446 power_poly_0   -> power_0
  2447 power_poly_Suc -> power_Suc
  2448 
  2449 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2450 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2451 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2452 of lemmas from Divides has been generalized from nat to class
  2453 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2454 renames resulting from duplicate elimination:
  2455 
  2456     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2457     zero_dvd_iff ~>         dvd_0_left_iff
  2458     dvd_0 ~>                dvd_0_right
  2459     DIVISION_BY_ZERO_DIV ~> div_by_0
  2460     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2461     mult_div ~>             div_mult_self2_is_id
  2462     mult_mod ~>             mod_mult_self2_is_0
  2463 
  2464 * Theory IntDiv: removed many lemmas that are instances of class-based
  2465 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2466 rename old lemmas as follows:
  2467 
  2468 dvd_diff               -> nat_dvd_diff
  2469 dvd_zminus_iff         -> dvd_minus_iff
  2470 mod_add1_eq            -> mod_add_eq
  2471 mod_mult1_eq           -> mod_mult_right_eq
  2472 mod_mult1_eq'          -> mod_mult_left_eq
  2473 mod_mult_distrib_mod   -> mod_mult_eq
  2474 nat_mod_add_left_eq    -> mod_add_left_eq
  2475 nat_mod_add_right_eq   -> mod_add_right_eq
  2476 nat_mod_div_trivial    -> mod_div_trivial
  2477 nat_mod_mod_trivial    -> mod_mod_trivial
  2478 zdiv_zadd_self1        -> div_add_self1
  2479 zdiv_zadd_self2        -> div_add_self2
  2480 zdiv_zmult_self1       -> div_mult_self2_is_id
  2481 zdiv_zmult_self2       -> div_mult_self1_is_id
  2482 zdvd_triv_left         -> dvd_triv_left
  2483 zdvd_triv_right        -> dvd_triv_right
  2484 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2485 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2486 zmod_zadd_left_eq      -> mod_add_left_eq
  2487 zmod_zadd_right_eq     -> mod_add_right_eq
  2488 zmod_zadd_self1        -> mod_add_self1
  2489 zmod_zadd_self2        -> mod_add_self2
  2490 zmod_zadd1_eq          -> mod_add_eq
  2491 zmod_zdiff1_eq         -> mod_diff_eq
  2492 zmod_zdvd_zmod         -> mod_mod_cancel
  2493 zmod_zmod_cancel       -> mod_mod_cancel
  2494 zmod_zmult_self1       -> mod_mult_self2_is_0
  2495 zmod_zmult_self2       -> mod_mult_self1_is_0
  2496 zmod_1                 -> mod_by_1
  2497 zdiv_1                 -> div_by_1
  2498 zdvd_abs1              -> abs_dvd_iff
  2499 zdvd_abs2              -> dvd_abs_iff
  2500 zdvd_refl              -> dvd_refl
  2501 zdvd_trans             -> dvd_trans
  2502 zdvd_zadd              -> dvd_add
  2503 zdvd_zdiff             -> dvd_diff
  2504 zdvd_zminus_iff        -> dvd_minus_iff
  2505 zdvd_zminus2_iff       -> minus_dvd_iff
  2506 zdvd_zmultD            -> dvd_mult_right
  2507 zdvd_zmultD2           -> dvd_mult_left
  2508 zdvd_zmult_mono        -> mult_dvd_mono
  2509 zdvd_0_right           -> dvd_0_right
  2510 zdvd_0_left            -> dvd_0_left_iff
  2511 zdvd_1_left            -> one_dvd
  2512 zminus_dvd_iff         -> minus_dvd_iff
  2513 
  2514 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2515 
  2516 * The real numbers offer decimal input syntax: 12.34 is translated
  2517 into 1234/10^2. This translation is not reversed upon output.
  2518 
  2519 * Theory Library/Polynomial defines an abstract type 'a poly of
  2520 univariate polynomials with coefficients of type 'a.  In addition to
  2521 the standard ring operations, it also supports div and mod.  Code
  2522 generation is also supported, using list-style constructors.
  2523 
  2524 * Theory Library/Inner_Product defines a class of real_inner for real
  2525 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2526 => real.  Class real_inner is a subclass of real_normed_vector from
  2527 theory RealVector.
  2528 
  2529 * Theory Library/Product_Vector provides instances for the product
  2530 type 'a * 'b of several classes from RealVector and Inner_Product.
  2531 Definitions of addition, subtraction, scalar multiplication, norms,
  2532 and inner products are included.
  2533 
  2534 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2535 addition to the field operations, numerals and case syntax are also
  2536 supported.
  2537 
  2538 * Theory Library/Diagonalize provides constructive version of Cantor's
  2539 first diagonalization argument.
  2540 
  2541 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2542 zlcm (for int); carried together from various gcd/lcm developements in
  2543 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2544 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2545 may recover tupled syntax as follows:
  2546 
  2547     hide (open) const gcd
  2548     abbreviation gcd where
  2549       "gcd == (%(a, b). GCD.gcd a b)"
  2550     notation (output)
  2551       GCD.gcd ("gcd '(_, _')")
  2552 
  2553 The same works for lcm, zgcd, zlcm.
  2554 
  2555 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2556 instantiations for algebraic structures.  Removed some duplicate
  2557 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2558 
  2559 * ML antiquotation @{code} takes a constant as argument and generates
  2560 corresponding code in background and inserts name of the corresponding
  2561 resulting ML value/function/datatype constructor binding in place.
  2562 All occurrences of @{code} with a single ML block are generated
  2563 simultaneously.  Provides a generic and safe interface for
  2564 instrumentalizing code generation.  See
  2565 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2566 In future you ought to refrain from ad-hoc compiling generated SML
  2567 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2568 cannot refer to constants for which user-defined serializations are
  2569 set.  Refer to the corresponding ML counterpart directly in that
  2570 cases.
  2571 
  2572 * Command 'rep_datatype': instead of theorem names the command now
  2573 takes a list of terms denoting the constructors of the type to be
  2574 represented as datatype.  The characteristic theorems have to be
  2575 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2576 have disappeared in favour of existing ones:
  2577 
  2578     unit_induct                 ~> unit.induct
  2579     prod_induct                 ~> prod.induct
  2580     sum_induct                  ~> sum.induct
  2581     Suc_Suc_eq                  ~> nat.inject
  2582     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2583 
  2584 
  2585 *** HOL-Algebra ***
  2586 
  2587 * New locales for orders and lattices where the equivalence relation
  2588 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2589 locales use a record structure with field eq for the equivalence.
  2590 
  2591 * New theory of factorial domains.
  2592 
  2593 * Units_l_inv and Units_r_inv are now simp rules by default.
  2594 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2595 and/or r_inv will now also require deletion of these lemmas.
  2596 
  2597 * Renamed the following theorems, INCOMPATIBILITY:
  2598 
  2599 UpperD ~> Upper_memD
  2600 LowerD ~> Lower_memD
  2601 least_carrier ~> least_closed
  2602 greatest_carrier ~> greatest_closed
  2603 greatest_Lower_above ~> greatest_Lower_below
  2604 one_zero ~> carrier_one_zero
  2605 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2606 
  2607 
  2608 *** HOL-Nominal ***
  2609 
  2610 * Nominal datatypes can now contain type-variables.
  2611 
  2612 * Commands 'nominal_inductive' and 'equivariance' work with local
  2613 theory targets.
  2614 
  2615 * Nominal primrec can now works with local theory targets and its
  2616 specification syntax now conforms to the general format as seen in
  2617 'inductive' etc.
  2618 
  2619 * Method "perm_simp" honours the standard simplifier attributes
  2620 (no_asm), (no_asm_use) etc.
  2621 
  2622 * The new predicate #* is defined like freshness, except that on the
  2623 left hand side can be a set or list of atoms.
  2624 
  2625 * Experimental command 'nominal_inductive2' derives strong induction
  2626 principles for inductive definitions.  In contrast to
  2627 'nominal_inductive', which can only deal with a fixed number of
  2628 binders, it can deal with arbitrary expressions standing for sets of
  2629 atoms to be avoided.  The only inductive definition we have at the
  2630 moment that needs this generalisation is the typing rule for Lets in
  2631 the algorithm W:
  2632 
  2633  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2634  -----------------------------------------------------------------
  2635          Gamma |- Let x be t1 in t2 : T2
  2636 
  2637 In this rule one wants to avoid all the binders that are introduced by
  2638 "close Gamma T1".  We are looking for other examples where this
  2639 feature might be useful.  Please let us know.
  2640 
  2641 
  2642 *** HOLCF ***
  2643 
  2644 * Reimplemented the simplification procedure for proving continuity
  2645 subgoals.  The new simproc is extensible; users can declare additional
  2646 continuity introduction rules with the attribute [cont2cont].
  2647 
  2648 * The continuity simproc now uses a different introduction rule for
  2649 solving continuity subgoals on terms with lambda abstractions.  In
  2650 some rare cases the new simproc may fail to solve subgoals that the
  2651 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2652 Potential INCOMPATIBILITY.
  2653 
  2654 * Command 'fixrec': specification syntax now conforms to the general
  2655 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2656 examples.  INCOMPATIBILITY.
  2657 
  2658 
  2659 *** ZF ***
  2660 
  2661 * Proof of Zorn's Lemma for partial orders.
  2662 
  2663 
  2664 *** ML ***
  2665 
  2666 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2667 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2668 depends on multithreading, so timouts will not work before Poly/ML
  2669 5.2.1!
  2670 
  2671 * High-level support for concurrent ML programming, see
  2672 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2673 particularly convenient to organize independent functional
  2674 computations.  The concept of "synchronized variables" provides a
  2675 higher-order interface for components with shared state, avoiding the
  2676 delicate details of mutexes and condition variables.  (Requires
  2677 Poly/ML 5.2.1 or later.)
  2678 
  2679 * ML bindings produced via Isar commands are stored within the Isar
  2680 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2681 become thread-safe and work with undo as expected (concerning
  2682 top-level bindings, not side-effects on global references).
  2683 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2684 compiler at runtime; really global bindings need to be given outside a
  2685 theory.  (Requires Poly/ML 5.2 or later.)
  2686 
  2687 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2688 context.  Top-level ML bindings are stored within the proof context in
  2689 a purely sequential fashion, disregarding the nested proof structure.
  2690 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2691 proof.  (Requires Poly/ML 5.2 or later.)
  2692 
  2693 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2694 and Method.setup, as well as Isar commands 'attribute_setup' and
  2695 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2696 existing code accordingly, or use plain 'setup' together with old
  2697 Method.add_method.
  2698 
  2699 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2700 to 'a -> thm, while results are always tagged with an authentic oracle
  2701 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2702 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2703 accordingly.  Note that extra performance may be gained by producing
  2704 the cterm carefully, avoiding slow Thm.cterm_of.
  2705 
  2706 * Simplified interface for defining document antiquotations via
  2707 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2708 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2709 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2710 examples.
  2711 
  2712 * More systematic treatment of long names, abstract name bindings, and
  2713 name space operations.  Basic operations on qualified names have been
  2714 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2715 Long_Name.append.  Old type bstring has been mostly replaced by
  2716 abstract type binding (see structure Binding), which supports precise
  2717 qualification by packages and local theory targets, as well as proper
  2718 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2719 bstring values into Binding.name, or better pass through abstract
  2720 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2721 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2722 
  2723 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2724 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2725 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2726 
  2727 * Disposed old type and term read functions (Sign.read_def_typ,
  2728 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2729 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2730 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2731 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2732 resort for legacy applications.
  2733 
  2734 * Disposed old declarations, tactics, tactic combinators that refer to
  2735 the simpset or claset of an implicit theory (such as Addsimps,
  2736 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2737 embedded ML text, or local_simpset_of with a proper context passed as
  2738 explicit runtime argument.
  2739 
  2740 * Rules and tactics that read instantiations (read_instantiate,
  2741 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2742 context, which is required for parsing and type-checking.  Moreover,
  2743 the variables are specified as plain indexnames, not string encodings
  2744 thereof.  INCOMPATIBILITY.
  2745 
  2746 * Generic Toplevel.add_hook interface allows to analyze the result of
  2747 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2748 for theorem dependency output of transactions resulting in a new
  2749 theory state.
  2750 
  2751 * ML antiquotations: block-structured compilation context indicated by
  2752 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2753 
  2754   @{binding name}                         - basic name binding
  2755   @{let ?pat = term}                      - term abbreviation (HO matching)
  2756   @{note name = fact}                     - fact abbreviation
  2757   @{thm fact}                             - singleton fact (with attributes)
  2758   @{thms fact}                            - general fact (with attributes)
  2759   @{lemma prop by method}                 - singleton goal
  2760   @{lemma prop by meth1 meth2}            - singleton goal
  2761   @{lemma prop1 ... propN by method}      - general goal
  2762   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2763   @{lemma (open) ...}                     - open derivation
  2764 
  2765 
  2766 *** System ***
  2767 
  2768 * The Isabelle "emacs" tool provides a specific interface to invoke
  2769 Proof General / Emacs, with more explicit failure if that is not
  2770 installed (the old isabelle-interface script silently falls back on
  2771 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2772 installation location of the Proof General distribution.
  2773 
  2774 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2775 the Isabelle process into a JVM/Scala application.  See
  2776 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2777 process wrapper has been discontinued.)
  2778 
  2779 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2780 
  2781 * Various status messages (with exact source position information) are
  2782 emitted, if proper markup print mode is enabled.  This allows
  2783 user-interface components to provide detailed feedback on internal
  2784 prover operations.
  2785 
  2786 
  2787 
  2788 New in Isabelle2008 (June 2008)
  2789 -------------------------------
  2790 
  2791 *** General ***
  2792 
  2793 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2794 and updated, with formally checked references as hyperlinks.
  2795 
  2796 * Theory loader: use_thy (and similar operations) no longer set the
  2797 implicit ML context, which was occasionally hard to predict and in
  2798 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2799 provides a proper context already.
  2800 
  2801 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2802 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2803 'use' within a theory file will do the job.
  2804 
  2805 * Name space merge now observes canonical order, i.e. the second space
  2806 is inserted into the first one, while existing entries in the first
  2807 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2808 swap theory imports.
  2809 
  2810 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2811 INCOMPATIBILITY in identifier syntax etc.
  2812 
  2813 * Outer syntax: string tokens no longer admit escaped white space,
  2814 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2815 white space without escapes.
  2816 
  2817 * Outer syntax: string tokens may contain arbitrary character codes
  2818 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2819 "foo_bar".
  2820 
  2821 
  2822 *** Pure ***
  2823 
  2824 * Context-dependent token translations.  Default setup reverts locally
  2825 fixed variables, and adds hilite markup for undeclared frees.
  2826 
  2827 * Unused theorems can be found using the new command 'unused_thms'.
  2828 There are three ways of invoking it:
  2829 
  2830 (1) unused_thms
  2831      Only finds unused theorems in the current theory.
  2832 
  2833 (2) unused_thms thy_1 ... thy_n -
  2834      Finds unused theorems in the current theory and all of its ancestors,
  2835      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2836 
  2837 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2838      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2839      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2840      their ancestors.
  2841 
  2842 In order to increase the readability of the list produced by
  2843 unused_thms, theorems that have been created by a particular instance
  2844 of a theory command such as 'inductive' or 'function' are considered
  2845 to belong to the same "group", meaning that if at least one theorem in
  2846 this group is used, the other theorems in the same group are no longer
  2847 reported as unused.  Moreover, if all theorems in the group are
  2848 unused, only one theorem in the group is displayed.
  2849 
  2850 Note that proof objects have to be switched on in order for
  2851 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2852 usually the case when using Proof General with the default settings).
  2853 
  2854 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2855 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2856 duplicate fact bindings, or even accidental fact duplications.  Note
  2857 that tools may maintain dynamically scoped facts systematically, using
  2858 PureThy.add_thms_dynamic.
  2859 
  2860 * Command 'hide' now allows to hide from "fact" name space as well.
  2861 
  2862 * Eliminated destructive theorem database, simpset, claset, and
  2863 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2864 update of theories within ML code.
  2865 
  2866 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2867 INCOMPATIBILITY, object-logics depending on former Pure require
  2868 additional setup PureThy.old_appl_syntax_setup; object-logics
  2869 depending on former CPure need to refer to Pure.
  2870 
  2871 * Commands 'use' and 'ML' are now purely functional, operating on
  2872 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2873 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2874 INCOMPATIBILITY.
  2875 
  2876 * Command 'setup': discontinued implicit version with ML reference.
  2877 
  2878 * Instantiation target allows for simultaneous specification of class
  2879 instance operations together with an instantiation proof.
  2880 Type-checking phase allows to refer to class operations uniformly.
  2881 See src/HOL/Complex/Complex.thy for an Isar example and
  2882 src/HOL/Library/Eval.thy for an ML example.
  2883 
  2884 * Indexing of literal facts: be more serious about including only
  2885 facts from the visible specification/proof context, but not the
  2886 background context (locale etc.).  Affects `prop` notation and method
  2887 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2888 situations.
  2889 
  2890 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2891 "(open)" option, which used to expose internal bound variables to the
  2892 proof text.
  2893 
  2894 * Isar statements: removed obsolete case "rule_context".
  2895 INCOMPATIBILITY, better use explicit fixes/assumes.
  2896 
  2897 * Locale proofs: default proof step now includes 'unfold_locales';
  2898 hence 'proof' without argument may be used to unfold locale
  2899 predicates.
  2900 
  2901 
  2902 *** Document preparation ***
  2903 
  2904 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2905 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2906 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2907 spot); renamed link color from "darkblue" to "linkcolor" (default
  2908 value unchanged, can be redefined via \definecolor); no longer sets
  2909 "a4paper" option (unnecessary or even intrusive).
  2910 
  2911 * Antiquotation @{lemma A method} proves proposition A by the given
  2912 method (either a method name or a method name plus (optional) method
  2913 arguments in parentheses) and prints A just like @{prop A}.
  2914 
  2915 
  2916 *** HOL ***
  2917 
  2918 * New primrec package.  Specification syntax conforms in style to
  2919 definition/function/....  No separate induction rule is provided.  The
  2920 "primrec" command distinguishes old-style and new-style specifications
  2921 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2922 When adjusting theories, beware: constants stemming from new-style
  2923 primrec specifications have authentic syntax.
  2924 
  2925 * Metis prover is now an order of magnitude faster, and also works
  2926 with multithreading.
  2927 
  2928 * Metis: the maximum number of clauses that can be produced from a
  2929 theorem is now given by the attribute max_clauses.  Theorems that
  2930 exceed this number are ignored, with a warning printed.
  2931 
  2932 * Sledgehammer no longer produces structured proofs by default. To
  2933 enable, declare [[sledgehammer_full = true]].  Attributes
  2934 reconstruction_modulus, reconstruction_sorts renamed
  2935 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2936 
  2937 * Method "induct_scheme" derives user-specified induction rules
  2938 from well-founded induction and completeness of patterns. This factors
  2939 out some operations that are done internally by the function package
  2940 and makes them available separately.  See
  2941 src/HOL/ex/Induction_Scheme.thy for examples.
  2942 
  2943 * More flexible generation of measure functions for termination
  2944 proofs: Measure functions can be declared by proving a rule of the
  2945 form "is_measure f" and giving it the [measure_function] attribute.
  2946 The "is_measure" predicate is logically meaningless (always true), and
  2947 just guides the heuristic.  To find suitable measure functions, the
  2948 termination prover sets up the goal "is_measure ?f" of the appropriate
  2949 type and generates all solutions by prolog-style backwards proof using
  2950 the declared rules.
  2951 
  2952 This setup also deals with rules like 
  2953 
  2954   "is_measure f ==> is_measure (list_size f)"
  2955 
  2956 which accommodates nested datatypes that recurse through lists.
  2957 Similar rules are predeclared for products and option types.
  2958 
  2959 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2960 
  2961   INCOMPATIBILITIES:
  2962 
  2963   - Definitions of overloaded constants on sets have to be replaced by
  2964     definitions on => and bool.
  2965 
  2966   - Some definitions of overloaded operators on sets can now be proved
  2967     using the definitions of the operators on => and bool.  Therefore,
  2968     the following theorems have been renamed:
  2969 
  2970       subset_def   -> subset_eq
  2971       psubset_def  -> psubset_eq
  2972       set_diff_def -> set_diff_eq
  2973       Compl_def    -> Compl_eq
  2974       Sup_set_def  -> Sup_set_eq
  2975       Inf_set_def  -> Inf_set_eq
  2976       sup_set_def  -> sup_set_eq
  2977       inf_set_def  -> inf_set_eq
  2978 
  2979   - Due to the incompleteness of the HO unification algorithm, some
  2980     rules such as subst may require manual instantiation, if some of
  2981     the unknowns in the rule is a set.
  2982 
  2983   - Higher order unification and forward proofs:
  2984     The proof pattern
  2985 
  2986       have "P (S::'a set)" <...>
  2987       then have "EX S. P S" ..
  2988 
  2989     no longer works (due to the incompleteness of the HO unification
  2990     algorithm) and must be replaced by the pattern
  2991 
  2992       have "EX S. P S"
  2993       proof
  2994         show "P S" <...>
  2995       qed
  2996 
  2997   - Calculational reasoning with subst (or similar rules):
  2998     The proof pattern
  2999 
  3000       have "P (S::'a set)" <...>
  3001       also have "S = T" <...>
  3002       finally have "P T" .
  3003 
  3004     no longer works (for similar reasons as the previous example) and
  3005     must be replaced by something like
  3006 
  3007       have "P (S::'a set)" <...>
  3008       moreover have "S = T" <...>
  3009       ultimately have "P T" by simp
  3010 
  3011   - Tactics or packages written in ML code:
  3012     Code performing pattern matching on types via
  3013 
  3014       Type ("set", [T]) => ...
  3015 
  3016     must be rewritten. Moreover, functions like strip_type or
  3017     binder_types no longer return the right value when applied to a
  3018     type of the form
  3019 
  3020       T1 => ... => Tn => U => bool
  3021 
  3022     rather than
  3023 
  3024       T1 => ... => Tn => U set
  3025 
  3026 * Merged theories Wellfounded_Recursion, Accessible_Part and
  3027 Wellfounded_Relations to theory Wellfounded.
  3028 
  3029 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  3030 
  3031 * Class finite no longer treats UNIV as class parameter.  Use class
  3032 enum from theory Library/Enum instead to achieve a similar effect.
  3033 INCOMPATIBILITY.
  3034 
  3035 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  3036 and "Cons".  INCOMPATIBILITY.
  3037 
  3038 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  3039 Potential INCOMPATIBILITY.
  3040 
  3041 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  3042 injective_fst_snd removed, use split_eta and prod_eqI instead.
  3043 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  3044 
  3045 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  3046 the same name in theory Orderings:
  3047 
  3048   less_trans
  3049   less_linear
  3050   le_imp_less_or_eq
  3051   le_less_trans
  3052   less_le_trans
  3053   less_not_sym
  3054   less_asym
  3055 
  3056 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  3057 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  3058 and different variable names.
  3059 
  3060 * Library/Option_ord.thy: Canonical order on option type.
  3061 
  3062 * Library/RBT.thy: Red-black trees, an efficient implementation of
  3063 finite maps.
  3064 
  3065 * Library/Countable.thy: Type class for countable types.
  3066 
  3067 * Theory Int: The representation of numerals has changed.  The infix
  3068 operator BIT and the bit datatype with constructors B0 and B1 have
  3069 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  3070 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  3071 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  3072 accordingly.
  3073 
  3074 * Theory Nat: definition of <= and < on natural numbers no longer
  3075 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  3076 le_def and less_def have disappeared.  Consider lemmas not_less
  3077 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  3078 
  3079 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  3080 (whose purpose mainly is for various fold_set functionals) have been
  3081 abandoned in favor of the existing algebraic classes
  3082 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  3083 lower_semilattice (resp. upper_semilattice) and linorder.
  3084 INCOMPATIBILITY.
  3085 
  3086 * Theory Transitive_Closure: induct and cases rules now declare proper
  3087 case_names ("base" and "step").  INCOMPATIBILITY.
  3088 
  3089 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  3090 lattices.  The form set-specific version is available as
  3091 Inductive.lfp_ordinal_induct_set.
  3092 
  3093 * Renamed theorems "power.simps" to "power_int.simps".
  3094 INCOMPATIBILITY.
  3095 
  3096 * Class semiring_div provides basic abstract properties of semirings
  3097 with division and modulo operations.  Subsumes former class dvd_mod.
  3098 
  3099 * Merged theories IntDef, Numeral and IntArith into unified theory
  3100 Int.  INCOMPATIBILITY.
  3101 
  3102 * Theory Library/Code_Index: type "index" now represents natural
  3103 numbers rather than integers.  INCOMPATIBILITY.
  3104 
  3105 * New class "uminus" with operation "uminus" (split of from class
  3106 "minus" which now only has operation "minus", binary).
  3107 INCOMPATIBILITY.
  3108 
  3109 * Constants "card", "internal_split", "option_map" now with authentic
  3110 syntax.  INCOMPATIBILITY.
  3111 
  3112 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3113 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3114 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3115 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3116 Sup_set_def, le_def, less_def, option_map_def now with object
  3117 equality.  INCOMPATIBILITY.
  3118 
  3119 * Records. Removed K_record, and replaced it by pure lambda term
  3120 %x. c. The simplifier setup is now more robust against eta expansion.
  3121 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3122 
  3123 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3124 
  3125 * Library/ListVector: new theory of arithmetic vector operations.
  3126 
  3127 * Library/Order_Relation: new theory of various orderings as sets of
  3128 pairs.  Defines preorders, partial orders, linear orders and
  3129 well-orders on sets and on types.
  3130 
  3131 
  3132 *** ZF ***
  3133 
  3134 * Renamed some theories to allow to loading both ZF and HOL in the
  3135 same session:
  3136 
  3137   Datatype  -> Datatype_ZF
  3138   Inductive -> Inductive_ZF
  3139   Int       -> Int_ZF
  3140   IntDiv    -> IntDiv_ZF
  3141   Nat       -> Nat_ZF
  3142   List      -> List_ZF
  3143   Main      -> Main_ZF
  3144 
  3145 INCOMPATIBILITY: ZF theories that import individual theories below
  3146 Main might need to be adapted.  Regular theory Main is still
  3147 available, as trivial extension of Main_ZF.
  3148 
  3149 
  3150 *** ML ***
  3151 
  3152 * ML within Isar: antiquotation @{const name} or @{const
  3153 name(typargs)} produces statically-checked Const term.
  3154 
  3155 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3156 (of the same name).  Removed obsolete print command.
  3157 
  3158 * Removed obsolete "use_legacy_bindings" function.
  3159 
  3160 * The ``print mode'' is now a thread-local value derived from a global
  3161 template (the former print_mode reference), thus access becomes
  3162 non-critical.  The global print_mode reference is for session
  3163 management only; user-code should use print_mode_value,
  3164 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3165 
  3166 * Functions system/system_out provide a robust way to invoke external
  3167 shell commands, with propagation of interrupts (requires Poly/ML
  3168 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3169 
  3170 
  3171 *** System ***
  3172 
  3173 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3174 in accordance with Proof General 3.7, which prefers GNU emacs.
  3175 
  3176 * isatool tty runs Isabelle process with plain tty interaction;
  3177 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3178 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3179 
  3180 * isatool browser now works with Cygwin as well, using general
  3181 "javapath" function defined in Isabelle process environment.
  3182 
  3183 * YXML notation provides a simple and efficient alternative to
  3184 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3185 isatool yxml as described in the Isabelle system manual.
  3186 
  3187 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3188 provides general wrapper for managing an Isabelle process in a robust
  3189 fashion, with ``cooked'' output from stdin/stderr.
  3190 
  3191 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3192 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3193 
  3194 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3195 way of changing the user's settings is via
  3196 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3197 script.
  3198 
  3199 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3200 cores of the underlying machine, which is a good starting point for
  3201 optimal performance tuning.  The corresponding usedir option -M allows
  3202 "max" as an alias for "0".  WARNING: does not work on certain versions
  3203 of Mac OS (with Poly/ML 5.1).
  3204 
  3205 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3206 adverse effect of Isabelle flooding interactive front-ends (notably
  3207 ProofGeneral / XEmacs).
  3208 
  3209 
  3210 
  3211 New in Isabelle2007 (November 2007)
  3212 -----------------------------------
  3213 
  3214 *** General ***
  3215 
  3216 * More uniform information about legacy features, notably a
  3217 warning/error of "Legacy feature: ...", depending on the state of the
  3218 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3219 legacy features will disappear eventually.
  3220 
  3221 * Theory syntax: the header format ``theory A = B + C:'' has been
  3222 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3223 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3224 
  3225 * Theory syntax: the old non-Isar theory file format has been
  3226 discontinued altogether.  Note that ML proof scripts may still be used
  3227 with Isar theories; migration is usually quite simple with the ML
  3228 function use_legacy_bindings.  INCOMPATIBILITY.
  3229 
  3230 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3231 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3232 quotes.
  3233 
  3234 * Theory loader: be more serious about observing the static theory
  3235 header specifications (including optional directories), but not the
  3236 accidental file locations of previously successful loads.  The strict
  3237 update policy of former update_thy is now already performed by
  3238 use_thy, so the former has been removed; use_thys updates several
  3239 theories simultaneously, just as 'imports' within a theory header
  3240 specification, but without merging the results.  Potential
  3241 INCOMPATIBILITY: may need to refine theory headers and commands
  3242 ROOT.ML which depend on load order.
  3243 
  3244 * Theory loader: optional support for content-based file
  3245 identification, instead of the traditional scheme of full physical
  3246 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3247 (cf. the system manual).  The new scheme allows to work with
  3248 non-finished theories in persistent session images, such that source
  3249 files may be moved later on without requiring reloads.
  3250 
  3251 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3252 file (with the same base name as the theory) are considered a legacy
  3253 feature, which will disappear eventually. Even now, the theory loader
  3254 no longer maintains dependencies on such files.
  3255 
  3256 * Syntax: the scope for resolving ambiguities via type-inference is
  3257 now limited to individual terms, instead of whole simultaneous
  3258 specifications as before. This greatly reduces the complexity of the
  3259 syntax module and improves flexibility by separating parsing and
  3260 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3261 'fixes' etc.) are required in rare situations.
  3262 
  3263 * Syntax: constants introduced by new-style packages ('definition',
  3264 'abbreviation' etc.) are passed through the syntax module in
  3265 ``authentic mode''. This means that associated mixfix annotations
  3266 really stick to such constants, independently of potential name space
  3267 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3268 trees are represented slightly differently, may need to adapt syntax
  3269 translations accordingly. Use CONST marker in 'translations' and
  3270 @{const_syntax} antiquotation in 'parse_translation' etc.
  3271 
  3272 * Legacy goal package: reduced interface to the bare minimum required
  3273 to keep existing proof scripts running.  Most other user-level
  3274 functions are now part of the OldGoals structure, which is *not* open
  3275 by default (consider isatool expandshort before open OldGoals).
  3276 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3277 these tend to cause confusion about the actual goal (!) context being
  3278 used here, which is not necessarily the same as the_context().
  3279 
  3280 * Command 'find_theorems': supports "*" wild-card in "name:"
  3281 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3282 support a specific search form (see ProofGeneral/CHANGES).
  3283 
  3284 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3285 by default, which means that "prems" (and also "fixed variables") are
  3286 suppressed from proof state output.  Note that the ProofGeneral
  3287 settings mechanism allows to change and save options persistently, but
  3288 older versions of Isabelle will fail to start up if a negative prems
  3289 limit is imposed.
  3290 
  3291 * Local theory targets may be specified by non-nested blocks of
  3292 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3293 contain definitions, theorems etc., including any derived mechanism
  3294 that has been implemented on top of these primitives.  This concept
  3295 generalizes the existing ``theorem (in ...)'' towards more versatility
  3296 and scalability.
  3297 
  3298 * Proof General interface: proper undo of final 'end' command;
  3299 discontinued Isabelle/classic mode (ML proof scripts).
  3300 
  3301 
  3302 *** Document preparation ***
  3303 
  3304 * Added antiquotation @{theory name} which prints the given name,
  3305 after checking that it refers to a valid ancestor theory in the
  3306 current context.
  3307 
  3308 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3309 check the given source text as ML type/structure, printing verbatim.
  3310 
  3311 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3312 "c args == rhs" given in the current context.  (Any number of
  3313 arguments may be given on the LHS.)
  3314 
  3315 
  3316 *** Pure ***
  3317 
  3318 * The 'class' package offers a combination of axclass and locale to
  3319 achieve Haskell-like type classes in Isabelle.  Definitions and
  3320 theorems within a class context produce both relative results (with
  3321 implicit parameters according to the locale context), and polymorphic
  3322 constants with qualified polymorphism (according to the class
  3323 context).  Within the body context of a 'class' target, a separate
  3324 syntax layer ("user space type system") takes care of converting
  3325 between global polymorphic consts and internal locale representation.
  3326 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3327 "isatool doc classes" provides a tutorial.
  3328 
  3329 * Generic code generator framework allows to generate executable
  3330 code for ML and Haskell (including Isabelle classes).  A short usage
  3331 sketch:
  3332 
  3333     internal compilation:
  3334         export_code <list of constants (term syntax)> in SML
  3335     writing SML code to a file:
  3336         export_code <list of constants (term syntax)> in SML <filename>
  3337     writing OCaml code to a file:
  3338         export_code <list of constants (term syntax)> in OCaml <filename>
  3339     writing Haskell code to a bunch of files:
  3340         export_code <list of constants (term syntax)> in Haskell <filename>
  3341 
  3342     evaluating closed propositions to True/False using code generation:
  3343         method ``eval''
  3344 
  3345 Reasonable default setup of framework in HOL.
  3346 
  3347 Theorem attributs for selecting and transforming function equations theorems:
  3348 
  3349     [code fun]:        select a theorem as function equation for a specific constant
  3350     [code fun del]:    deselect a theorem as function equation for a specific constant
  3351     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3352     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3353 
  3354 User-defined serializations (target in {SML, OCaml, Haskell}):
  3355 
  3356     code_const <and-list of constants (term syntax)>
  3357       {(target) <and-list of const target syntax>}+
  3358 
  3359     code_type <and-list of type constructors>
  3360       {(target) <and-list of type target syntax>}+
  3361 
  3362     code_instance <and-list of instances>
  3363       {(target)}+
  3364         where instance ::= <type constructor> :: <class>
  3365 
  3366     code_class <and_list of classes>
  3367       {(target) <and-list of class target syntax>}+
  3368         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3369 
  3370 code_instance and code_class only are effective to target Haskell.
  3371 
  3372 For example usage see src/HOL/ex/Codegenerator.thy and
  3373 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3374 generation from Isabelle/HOL theories is available via "isatool doc
  3375 codegen".
  3376 
  3377 * Code generator: consts in 'consts_code' Isar commands are now
  3378 referred to by usual term syntax (including optional type
  3379 annotations).
  3380 
  3381 * Command 'no_translations' removes translation rules from theory
  3382 syntax.
  3383 
  3384 * Overloaded definitions are now actually checked for acyclic
  3385 dependencies.  The overloading scheme is slightly more general than
  3386 that of Haskell98, although Isabelle does not demand an exact
  3387 correspondence to type class and instance declarations.
  3388 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3389 exotic versions of overloading -- at the discretion of the user!
  3390 
  3391 Polymorphic constants are represented via type arguments, i.e. the
  3392 instantiation that matches an instance against the most general
  3393 declaration given in the signature.  For example, with the declaration
  3394 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3395 as c(nat).  Overloading is essentially simultaneous structural
  3396 recursion over such type arguments.  Incomplete specification patterns
  3397 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3398 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3399 Command 'print_theory' outputs the normalized system of recursive
  3400 equations, see section "definitions".
  3401 
  3402 * Configuration options are maintained within the theory or proof
  3403 context (with name and type bool/int/string), providing a very simple
  3404 interface to a poor-man's version of general context data.  Tools may
  3405 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3406 these values using Config.get etc.  Users may change options via an
  3407 associated attribute of the same name.  This form of context
  3408 declaration works particularly well with commands 'declare' or
  3409 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3410 very easy to avoid global references, which would not observe Isar
  3411 toplevel undo/redo and fail to work with multithreading.
  3412 
  3413 Various global ML references of Pure and HOL have been turned into
  3414 configuration options:
  3415 
  3416   Unify.search_bound		unify_search_bound
  3417   Unify.trace_bound		unify_trace_bound
  3418   Unify.trace_simp		unify_trace_simp
  3419   Unify.trace_types		unify_trace_types
  3420   Simplifier.simp_depth_limit	simp_depth_limit
  3421   Blast.depth_limit		blast_depth_limit
  3422   DatatypeProp.dtK		datatype_distinctness_limit
  3423   fast_arith_neq_limit  	fast_arith_neq_limit
  3424   fast_arith_split_limit	fast_arith_split_limit
  3425 
  3426 * Named collections of theorems may be easily installed as context
  3427 data using the functor NamedThmsFun (see also
  3428 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3429 attributes; there is also a toplevel print command.  This facility is
  3430 just a common case of general context data, which is the preferred way
  3431 for anything more complex than just a list of facts in canonical
  3432 order.
  3433 
  3434 * Isar: command 'declaration' augments a local theory by generic
  3435 declaration functions written in ML.  This enables arbitrary content
  3436 being added to the context, depending on a morphism that tells the
  3437 difference of the original declaration context wrt. the application
  3438 context encountered later on.
  3439 
  3440 * Isar: proper interfaces for simplification procedures.  Command
  3441 'simproc_setup' declares named simprocs (with match patterns, and body
  3442 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3443 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3444 
  3445 * Isar: an extra pair of brackets around attribute declarations
  3446 abbreviates a theorem reference involving an internal dummy fact,
  3447 which will be ignored later --- only the effect of the attribute on
  3448 the background context will persist.  This form of in-place
  3449 declarations is particularly useful with commands like 'declare' and
  3450 'using', for example ``have A using [[simproc a]] by simp''.
  3451 
  3452 * Isar: method "assumption" (and implicit closing of subproofs) now
  3453 takes simple non-atomic goal assumptions into account: after applying
  3454 an assumption as a rule the resulting subgoals are solved by atomic
  3455 assumption steps.  This is particularly useful to finish 'obtain'
  3456 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3457 without referring to the original premise "!!x. P x ==> thesis" in the
  3458 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3459 more permissive.
  3460 
  3461 * Isar: implicit use of prems from the Isar proof context is
  3462 considered a legacy feature.  Common applications like ``have A .''
  3463 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3464 referencing facts explicitly here improves readability and
  3465 maintainability of proof texts.
  3466 
  3467 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3468 the obtained context from the course of reasoning!  For example:
  3469 
  3470   assume "EX x y. A x & B y"   -- "any previous fact"
  3471   then guess x and y by clarify
  3472 
  3473 This technique is potentially adventurous, depending on the facts and
  3474 proof tools being involved here.
  3475 
  3476 * Isar: known facts from the proof context may be specified as literal
  3477 propositions, using ASCII back-quote syntax.  This works wherever
  3478 named facts used to be allowed so far, in proof commands, proof
  3479 methods, attributes etc.  Literal facts are retrieved from the context
  3480 according to unification of type and term parameters.  For example,
  3481 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3482 theorems in the current context, then these are valid literal facts:
  3483 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3484 
  3485 There is also a proof method "fact" which does the same composition
  3486 for explicit goal states, e.g. the following proof texts coincide with
  3487 certain special cases of literal facts:
  3488 
  3489   have "A" by fact                 ==  note `A`
  3490   have "A ==> B" by fact           ==  note `A ==> B`
  3491   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3492   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3493 
  3494 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3495 outer syntax.  Thus symbolic identifiers may be used without
  3496 additional white space in declarations like this: ``assume *: A''.
  3497 
  3498 * Isar: 'print_facts' prints all local facts of the current context,
  3499 both named and unnamed ones.
  3500 
  3501 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3502 
  3503   def x == "t" and y == "u"
  3504 
  3505 * Isar: added command 'unfolding', which is structurally similar to
  3506 'using', but affects both the goal state and facts by unfolding given
  3507 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3508 'unfolded' attribute may be replaced by first-class proof text.
  3509 
  3510 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3511 and command 'unfolding' now all support object-level equalities
  3512 (potentially conditional).  The underlying notion of rewrite rule is
  3513 analogous to the 'rule_format' attribute, but *not* that of the
  3514 Simplifier (which is usually more generous).
  3515 
  3516 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3517 premises of a theorem by n. Useful in conjunction with drule.
  3518 
  3519 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3520 method expression within a sandbox consisting of the first N
  3521 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3522 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3523 simplifies all new goals that emerge from applying rule foo to the
  3524 originally first one.
  3525 
  3526 * Isar: schematic goals are no longer restricted to higher-order
  3527 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3528 expected.
  3529 
  3530 * Isar: the conclusion of a long theorem statement is now either
  3531 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3532 (essentially a disjunction of cases with local parameters and
  3533 assumptions).  The latter allows to express general elimination rules
  3534 adequately; in this notation common elimination rules look like this:
  3535 
  3536   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3537     assumes "EX x. P x"
  3538     obtains x where "P x"
  3539 
  3540   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3541     assumes "A & B"
  3542     obtains A and B
  3543 
  3544   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3545     assumes "A | B"
  3546     obtains
  3547       A
  3548     | B
  3549 
  3550 The subsequent classical rules even refer to the formal "thesis"
  3551 explicitly:
  3552 
  3553   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3554     obtains "~ thesis"
  3555 
  3556   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3557     obtains "thesis ==> something"
  3558 
  3559 The actual proof of an 'obtains' statement is analogous to that of the
  3560 Isar proof element 'obtain', only that there may be several cases.
  3561 Optional case names may be specified in parentheses; these will be
  3562 available both in the present proof and as annotations in the
  3563 resulting rule, for later use with the 'cases' method (cf. attribute
  3564 case_names).
  3565 
  3566 * Isar: the assumptions of a long theorem statement are available as
  3567 "assms" fact in the proof context.  This is more appropriate than the
  3568 (historical) "prems", which refers to all assumptions of the current
  3569 context, including those from the target locale, proof body etc.
  3570 
  3571 * Isar: 'print_statement' prints theorems from the current theory or
  3572 proof context in long statement form, according to the syntax of a
  3573 top-level lemma.
  3574 
  3575 * Isar: 'obtain' takes an optional case name for the local context
  3576 introduction rule (default "that").
  3577 
  3578 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3579 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3580 to occur.
  3581 
  3582 * Pure: syntax "CONST name" produces a fully internalized constant
  3583 according to the current context.  This is particularly useful for
  3584 syntax translations that should refer to internal constant
  3585 representations independently of name spaces.
  3586 
  3587 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3588 instead of "FOO ". This allows multiple binder declarations to coexist
  3589 in the same context.  INCOMPATIBILITY.
  3590 
  3591 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3592 primitive that also works in a locale context (both for constants and
  3593 fixed variables). Type declaration and internal syntactic representation
  3594 of given constants retrieved from the context. Likewise, the
  3595 'no_notation' command allows to remove given syntax annotations from the
  3596 current context.
  3597 
  3598 * Isar/locales: new derived specification elements 'axiomatization',
  3599 'definition', 'abbreviation', which support type-inference, admit
  3600 object-level specifications (equality, equivalence).  See also the
  3601 isar-ref manual.  Examples:
  3602 
  3603   axiomatization
  3604     eq  (infix "===" 50) where
  3605     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3606 
  3607   definition "f x y = x + y + 1"
  3608   definition g where "g x = f x x"
  3609 
  3610   abbreviation
  3611     neq  (infix "=!=" 50) where
  3612     "x =!= y == ~ (x === y)"
  3613 
  3614 These specifications may be also used in a locale context.  Then the
  3615 constants being introduced depend on certain fixed parameters, and the
  3616 constant name is qualified by the locale base name.  An internal
  3617 abbreviation takes care for convenient input and output, making the
  3618 parameters implicit and using the original short name.  See also
  3619 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3620 entities from a monomorphic theory.
  3621 
  3622 Presently, abbreviations are only available 'in' a target locale, but
  3623 not inherited by general import expressions.  Also note that
  3624 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3625 'translations' in common applications.  The "no_abbrevs" print mode
  3626 prevents folding of abbreviations in term output.
  3627 
  3628 Concrete syntax is attached to specified constants in internal form,
  3629 independently of name spaces.  The parse tree representation is
  3630 slightly different -- use 'notation' instead of raw 'syntax', and
  3631 'translations' with explicit "CONST" markup to accommodate this.
  3632 
  3633 * Pure/Isar: unified syntax for new-style specification mechanisms
  3634 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3635 full type inference and dummy patterns ("_").  For example:
  3636 
  3637   definition "K x _ = x"
  3638 
  3639   inductive conj for A B
  3640   where "A ==> B ==> conj A B"
  3641 
  3642 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3643 the current context.  Print mode "no_abbrevs" prevents inversion of
  3644 abbreviations on output.
  3645 
  3646 * Isar/locales: improved parameter handling: use of locales "var" and
  3647 "struct" no longer necessary; - parameter renamings are no longer
  3648 required to be injective.  For example, this allows to define
  3649 endomorphisms as locale endom = homom mult mult h.
  3650 
  3651 * Isar/locales: changed the way locales with predicates are defined.
  3652 Instead of accumulating the specification, the imported expression is
  3653 now an interpretation.  INCOMPATIBILITY: different normal form of
  3654 locale expressions.  In particular, in interpretations of locales with
  3655 predicates, goals repesenting already interpreted fragments are not
  3656 removed automatically.  Use methods `intro_locales' and
  3657 `unfold_locales'; see below.
  3658 
  3659 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3660 provide backward reasoning on locales predicates.  The methods are
  3661 aware of interpretations and discharge corresponding goals.
  3662 `intro_locales' is less aggressive then `unfold_locales' and does not
  3663 unfold predicates to assumptions.
  3664 
  3665 * Isar/locales: the order in which locale fragments are accumulated
  3666 has changed.  This enables to override declarations from fragments due
  3667 to interpretations -- for example, unwanted simp rules.
  3668 
  3669 * Isar/locales: interpretation in theories and proof contexts has been
  3670 extended.  One may now specify (and prove) equations, which are
  3671 unfolded in interpreted theorems.  This is useful for replacing
  3672 defined concepts (constants depending on locale parameters) by
  3673 concepts already existing in the target context.  Example:
  3674 
  3675   interpretation partial_order ["op <= :: [int, int] => bool"]
  3676     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3677 
  3678 Typically, the constant `partial_order.less' is created by a
  3679 definition specification element in the context of locale
  3680 partial_order.
  3681 
  3682 * Method "induct": improved internal context management to support
  3683 local fixes and defines on-the-fly. Thus explicit meta-level
  3684 connectives !!  and ==> are rarely required anymore in inductive goals
  3685 (using object-logic connectives for this purpose has been long
  3686 obsolete anyway). Common proof patterns are explained in
  3687 src/HOL/Induct/Common_Patterns.thy, see also
  3688 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3689 examples.
  3690 
  3691 * Method "induct": improved handling of simultaneous goals. Instead of
  3692 introducing object-level conjunction, the statement is now split into
  3693 several conclusions, while the corresponding symbolic cases are nested
  3694 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3695 see src/HOL/Induct/Common_Patterns.thy, for example.
  3696 
  3697 * Method "induct": mutual induction rules are now specified as a list
  3698 of rule sharing the same induction cases. HOL packages usually provide
  3699 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3700 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3701 mutual induction rules differently, i.e. like this:
  3702 
  3703   (induct rule: foo_bar.inducts)
  3704   (induct set: foo bar)
  3705   (induct pred: foo bar)
  3706   (induct type: foo bar)
  3707 
  3708 The ML function ProjectRule.projections turns old-style rules into the
  3709 new format.
  3710 
  3711 * Method "coinduct": dual of induction, see
  3712 src/HOL/Library/Coinductive_List.thy for various examples.
  3713 
  3714 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3715 considered a legacy feature.
  3716 
  3717 * Attribute "symmetric" produces result with standardized schematic
  3718 variables (index 0).  Potential INCOMPATIBILITY.
  3719 
  3720 * Simplifier: by default the simplifier trace only shows top level
  3721 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3722 default. Thus there is less danger of being flooded by the trace. The
  3723 trace indicates where parts have been suppressed.
  3724   
  3725 * Provers/classical: removed obsolete classical version of elim_format
  3726 attribute; classical elim/dest rules are now treated uniformly when
  3727 manipulating the claset.
  3728 
  3729 * Provers/classical: stricter checks to ensure that supplied intro,
  3730 dest and elim rules are well-formed; dest and elim rules must have at
  3731 least one premise.
  3732 
  3733 * Provers/classical: attributes dest/elim/intro take an optional
  3734 weight argument for the rule (just as the Pure versions).  Weights are
  3735 ignored by automated tools, but determine the search order of single
  3736 rule steps.
  3737 
  3738 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3739 where the body does not mention the bound variable.  Note that dummy
  3740 patterns implicitly depend on their context of bounds, which makes
  3741 "{_. _}" match any set comprehension as expected.  Potential
  3742 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3743 constant "_idtdummy" in the binding position.
  3744 
  3745 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3746 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3747 for example "A -> B" => "Pi A (%_. B)".
  3748 
  3749 * Pure: 'class_deps' command visualizes the subclass relation, using
  3750 the graph browser tool.
  3751 
  3752 * Pure: 'print_theory' now suppresses certain internal declarations by
  3753 default; use '!' option for full details.
  3754 
  3755 
  3756 *** HOL ***
  3757 
  3758 * Method "metis" proves goals by applying the Metis general-purpose
  3759 resolution prover (see also http://gilith.com/software/metis/).
  3760 Examples are in the directory MetisExamples.  WARNING: the
  3761 Isabelle/HOL-Metis integration does not yet work properly with
  3762 multi-threading.
  3763   
  3764 * Command 'sledgehammer' invokes external automatic theorem provers as
  3765 background processes.  It generates calls to the "metis" method if
  3766 successful. These can be pasted into the proof.  Users do not have to
  3767 wait for the automatic provers to return.  WARNING: does not really
  3768 work with multi-threading.
  3769 
  3770 * New "auto_quickcheck" feature tests outermost goal statements for
  3771 potential counter-examples.  Controlled by ML references
  3772 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3773 5000 milliseconds).  Fails silently if statements is outside of
  3774 executable fragment, or any other codgenerator problem occurs.
  3775 
  3776 * New constant "undefined" with axiom "undefined x = undefined".
  3777 
  3778 * Added class "HOL.eq", allowing for code generation with polymorphic
  3779 equality.
  3780 
  3781 * Some renaming of class constants due to canonical name prefixing in
  3782 the new 'class' package:
  3783 
  3784     HOL.abs ~> HOL.abs_class.abs
  3785     HOL.divide ~> HOL.divide_class.divide
  3786     0 ~> HOL.zero_class.zero
  3787     1 ~> HOL.one_class.one
  3788     op + ~> HOL.plus_class.plus
  3789     op - ~> HOL.minus_class.minus
  3790     uminus ~> HOL.minus_class.uminus
  3791     op * ~> HOL.times_class.times
  3792     op < ~> HOL.ord_class.less
  3793     op <= > HOL.ord_class.less_eq
  3794     Nat.power ~> Power.power_class.power
  3795     Nat.size ~> Nat.size_class.size
  3796     Numeral.number_of ~> Numeral.number_class.number_of
  3797     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3798     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3799     Orderings.min ~> Orderings.ord_class.min
  3800     Orderings.max ~> Orderings.ord_class.max
  3801     Divides.op div ~> Divides.div_class.div
  3802     Divides.op mod ~> Divides.div_class.mod
  3803     Divides.op dvd ~> Divides.div_class.dvd
  3804 
  3805 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3806 
  3807 a) User-defined constants using any of the names "plus", "minus",
  3808 "times", "less" or "less_eq". The standard syntax translations for
  3809 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3810 names.
  3811 
  3812 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3813 INCOMPATIBILITY: use more specific names.
  3814 
  3815 c) Permutative equations (e.g. "a + b = b + a")
  3816 Since the change of names also changes the order of terms, permutative
  3817 rewrite rules may get applied in a different order. Experience shows
  3818 that this is rarely the case (only two adaptions in the whole Isabelle
  3819 distribution).  INCOMPATIBILITY: rewrite proofs
  3820 
  3821 d) ML code directly refering to constant names
  3822 This in general only affects hand-written proof tactics, simprocs and
  3823 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3824 Consider using @{const_name} antiquotation.
  3825 
  3826 * New class "default" with associated constant "default".
  3827 
  3828 * Function "sgn" is now overloaded and available on int, real, complex
  3829 (and other numeric types), using class "sgn".  Two possible defs of
  3830 sgn are given as equational assumptions in the classes sgn_if and
  3831 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3832 INCOMPATIBILITY.
  3833 
  3834 * Locale "partial_order" now unified with class "order" (cf. theory
  3835 Orderings), added parameter "less".  INCOMPATIBILITY.
  3836 
  3837 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3838 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3839 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3840 
  3841 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3842 changed order of proof goals in instance proofs.
  3843 
  3844 * The transitivity reasoner for partial and linear orders is set up
  3845 for classes "order" and "linorder".  Instances of the reasoner are available
  3846 in all contexts importing or interpreting the corresponding locales.
  3847 Method "order" invokes the reasoner separately; the reasoner
  3848 is also integrated with the Simplifier as a solver.  Diagnostic
  3849 command 'print_orders' shows the available instances of the reasoner
  3850 in the current context.
  3851 
  3852 * Localized monotonicity predicate in theory "Orderings"; integrated
  3853 lemmas max_of_mono and min_of_mono with this predicate.
  3854 INCOMPATIBILITY.
  3855 
  3856 * Formulation of theorem "dense" changed slightly due to integration
  3857 with new class dense_linear_order.
  3858 
  3859 * Uniform lattice theory development in HOL.
  3860 
  3861     constants "meet" and "join" now named "inf" and "sup"
  3862     constant "Meet" now named "Inf"
  3863 
  3864     classes "meet_semilorder" and "join_semilorder" now named
  3865       "lower_semilattice" and "upper_semilattice"
  3866     class "lorder" now named "lattice"
  3867     class "comp_lat" now named "complete_lattice"
  3868 
  3869     Instantiation of lattice classes allows explicit definitions
  3870     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3871 
  3872   INCOMPATIBILITY.  Theorem renames:
  3873 
  3874     meet_left_le            ~> inf_le1
  3875     meet_right_le           ~> inf_le2
  3876     join_left_le            ~> sup_ge1
  3877     join_right_le           ~> sup_ge2
  3878     meet_join_le            ~> inf_sup_ord
  3879     le_meetI                ~> le_infI
  3880     join_leI                ~> le_supI
  3881     le_meet                 ~> le_inf_iff
  3882     le_join                 ~> ge_sup_conv
  3883     meet_idempotent         ~> inf_idem
  3884     join_idempotent         ~> sup_idem
  3885     meet_comm               ~> inf_commute
  3886     join_comm               ~> sup_commute
  3887     meet_leI1               ~> le_infI1
  3888     meet_leI2               ~> le_infI2
  3889     le_joinI1               ~> le_supI1
  3890     le_joinI2               ~> le_supI2
  3891     meet_assoc              ~> inf_assoc
  3892     join_assoc              ~> sup_assoc
  3893     meet_left_comm          ~> inf_left_commute
  3894     meet_left_idempotent    ~> inf_left_idem
  3895     join_left_comm          ~> sup_left_commute
  3896     join_left_idempotent    ~> sup_left_idem
  3897     meet_aci                ~> inf_aci
  3898     join_aci                ~> sup_aci
  3899     le_def_meet             ~> le_iff_inf
  3900     le_def_join             ~> le_iff_sup
  3901     join_absorp2            ~> sup_absorb2
  3902     join_absorp1            ~> sup_absorb1
  3903     meet_absorp1            ~> inf_absorb1
  3904     meet_absorp2            ~> inf_absorb2
  3905     meet_join_absorp        ~> inf_sup_absorb
  3906     join_meet_absorp        ~> sup_inf_absorb
  3907     distrib_join_le         ~> distrib_sup_le
  3908     distrib_meet_le         ~> distrib_inf_le
  3909 
  3910     add_meet_distrib_left   ~> add_inf_distrib_left
  3911     add_join_distrib_left   ~> add_sup_distrib_left
  3912     is_join_neg_meet        ~> is_join_neg_inf
  3913     is_meet_neg_join        ~> is_meet_neg_sup
  3914     add_meet_distrib_right  ~> add_inf_distrib_right
  3915     add_join_distrib_right  ~> add_sup_distrib_right
  3916     add_meet_join_distribs  ~> add_sup_inf_distribs
  3917     join_eq_neg_meet        ~> sup_eq_neg_inf
  3918     meet_eq_neg_join        ~> inf_eq_neg_sup
  3919     add_eq_meet_join        ~> add_eq_inf_sup
  3920     meet_0_imp_0            ~> inf_0_imp_0
  3921     join_0_imp_0            ~> sup_0_imp_0
  3922     meet_0_eq_0             ~> inf_0_eq_0
  3923     join_0_eq_0             ~> sup_0_eq_0
  3924     neg_meet_eq_join        ~> neg_inf_eq_sup
  3925     neg_join_eq_meet        ~> neg_sup_eq_inf
  3926     join_eq_if              ~> sup_eq_if
  3927 
  3928     mono_meet               ~> mono_inf
  3929     mono_join               ~> mono_sup
  3930     meet_bool_eq            ~> inf_bool_eq
  3931     join_bool_eq            ~> sup_bool_eq
  3932     meet_fun_eq             ~> inf_fun_eq
  3933     join_fun_eq             ~> sup_fun_eq
  3934     meet_set_eq             ~> inf_set_eq
  3935     join_set_eq             ~> sup_set_eq
  3936     meet1_iff               ~> inf1_iff
  3937     meet2_iff               ~> inf2_iff
  3938     meet1I                  ~> inf1I
  3939     meet2I                  ~> inf2I
  3940     meet1D1                 ~> inf1D1
  3941     meet2D1                 ~> inf2D1
  3942     meet1D2                 ~> inf1D2
  3943     meet2D2                 ~> inf2D2
  3944     meet1E                  ~> inf1E
  3945     meet2E                  ~> inf2E
  3946     join1_iff               ~> sup1_iff
  3947     join2_iff               ~> sup2_iff
  3948     join1I1                 ~> sup1I1
  3949     join2I1                 ~> sup2I1
  3950     join1I1                 ~> sup1I1
  3951     join2I2                 ~> sup1I2
  3952     join1CI                 ~> sup1CI
  3953     join2CI                 ~> sup2CI
  3954     join1E                  ~> sup1E
  3955     join2E                  ~> sup2E
  3956 
  3957     is_meet_Meet            ~> is_meet_Inf
  3958     Meet_bool_def           ~> Inf_bool_def
  3959     Meet_fun_def            ~> Inf_fun_def
  3960     Meet_greatest           ~> Inf_greatest
  3961     Meet_lower              ~> Inf_lower
  3962     Meet_set_def            ~> Inf_set_def
  3963 
  3964     Sup_def                 ~> Sup_Inf
  3965     Sup_bool_eq             ~> Sup_bool_def
  3966     Sup_fun_eq              ~> Sup_fun_def
  3967     Sup_set_eq              ~> Sup_set_def
  3968 
  3969     listsp_meetI            ~> listsp_infI
  3970     listsp_meet_eq          ~> listsp_inf_eq
  3971 
  3972     meet_min                ~> inf_min
  3973     join_max                ~> sup_max
  3974 
  3975 * Added syntactic class "size"; overloaded constant "size" now has
  3976 type "'a::size ==> bool"
  3977 
  3978 * Internal reorganisation of `size' of datatypes: size theorems
  3979 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3980 simplification rules by default!); theorems "prod.size" now named
  3981 "*.size".
  3982 
  3983 * Class "div" now inherits from class "times" rather than "type".
  3984 INCOMPATIBILITY.
  3985 
  3986 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  3987 Linorder etc.  have disappeared; operations defined in terms of
  3988 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  3989 
  3990 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  3991 
  3992 * HOL-Word: New extensive library and type for generic, fixed size
  3993 machine words, with arithemtic, bit-wise, shifting and rotating
  3994 operations, reflection into int, nat, and bool lists, automation for
  3995 linear arithmetic (by automatic reflection into nat or int), including
  3996 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  3997 arithmetic type classes, supporting automatic simplification of
  3998 numerals on all operations.
  3999 
  4000 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  4001 
  4002 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  4003 
  4004 * Code generator library theories:
  4005   - Code_Integer represents HOL integers by big integer literals in target
  4006     languages.
  4007   - Code_Char represents HOL characters by character literals in target
  4008     languages.
  4009   - Code_Char_chr like Code_Char, but also offers treatment of character
  4010     codes; includes Code_Integer.
  4011   - Executable_Set allows to generate code for finite sets using lists.
  4012   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  4013     denominator).
  4014   - Executable_Real implements a subset of real numbers, namly those
  4015     representable by rational numbers.
  4016   - Efficient_Nat implements natural numbers by integers, which in general will
  4017     result in higher efficency; pattern matching with 0/Suc is eliminated;
  4018     includes Code_Integer.
  4019   - Code_Index provides an additional datatype index which is mapped to
  4020     target-language built-in integers.
  4021   - Code_Message provides an additional datatype message_string which is isomorphic to
  4022     strings; messages are mapped to target-language strings.
  4023 
  4024 * New package for inductive predicates
  4025 
  4026   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  4027 
  4028     inductive
  4029       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4030       for z_1 :: U_1 and ... and z_n :: U_m
  4031     where
  4032       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4033     | ...
  4034 
  4035   with full support for type-inference, rather than
  4036 
  4037     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4038 
  4039     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4040     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4041 
  4042     inductive "s z_1 ... z_m"
  4043     intros
  4044       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4045       ...
  4046 
  4047   For backward compatibility, there is a wrapper allowing inductive
  4048   sets to be defined with the new package via
  4049 
  4050     inductive_set
  4051       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4052       for z_1 :: U_1 and ... and z_n :: U_m
  4053     where
  4054       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4055     | ...
  4056 
  4057   or
  4058 
  4059     inductive_set
  4060       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4061       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4062       for z_1 :: U_1 and ... and z_n :: U_m
  4063     where
  4064       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4065     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4066     | ...
  4067 
  4068   if the additional syntax "p ..." is required.
  4069 
  4070   Numerous examples can be found in the subdirectories src/HOL/Auth,
  4071   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  4072 
  4073   INCOMPATIBILITIES:
  4074 
  4075   - Since declaration and definition of inductive sets or predicates
  4076     is no longer separated, abbreviations involving the newly
  4077     introduced sets or predicates must be specified together with the
  4078     introduction rules after the 'where' keyword (see above), rather
  4079     than before the actual inductive definition.
  4080 
  4081   - The variables in induction and elimination rules are now
  4082     quantified in the order of their occurrence in the introduction
  4083     rules, rather than in alphabetical order. Since this may break
  4084     some proofs, these proofs either have to be repaired, e.g. by
  4085     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  4086     statements of the form
  4087 
  4088       case (rule_i a_i_1 ... a_i_{k_i})
  4089 
  4090     or the old order of quantification has to be restored by explicitly adding
  4091     meta-level quantifiers in the introduction rules, i.e.
  4092 
  4093       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  4094 
  4095   - The format of the elimination rules is now
  4096 
  4097       p z_1 ... z_m x_1 ... x_n ==>
  4098         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4099         ==> ... ==> P
  4100 
  4101     for predicates and
  4102 
  4103       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4104         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4105         ==> ... ==> P
  4106 
  4107     for sets rather than
  4108 
  4109       x : s z_1 ... z_m ==>
  4110         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4111         ==> ... ==> P
  4112 
  4113     This may require terms in goals to be expanded to n-tuples
  4114     (e.g. using case_tac or simplification with the split_paired_all
  4115     rule) before the above elimination rule is applicable.
  4116 
  4117   - The elimination or case analysis rules for (mutually) inductive
  4118     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4119     list of rules "p_1_..._p_k.elims" is no longer available.
  4120 
  4121 * New package "function"/"fun" for general recursive functions,
  4122 supporting mutual and nested recursion, definitions in local contexts,
  4123 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4124 for small examples, and the separate tutorial on the function
  4125 package. The old recdef "package" is still available as before, but
  4126 users are encouraged to use the new package.
  4127 
  4128 * Method "lexicographic_order" automatically synthesizes termination
  4129 relations as lexicographic combinations of size measures. 
  4130 
  4131 * Case-expressions allow arbitrary constructor-patterns (including
  4132 "_") and take their order into account, like in functional
  4133 programming.  Internally, this is translated into nested
  4134 case-expressions; missing cases are added and mapped to the predefined
  4135 constant "undefined". In complicated cases printing may no longer show
  4136 the original input but the internal form. Lambda-abstractions allow
  4137 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4138 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4139 variable.
  4140 
  4141 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4142 is an abbreviation for "of_nat :: nat => int". The simplification
  4143 rules for "of_nat" have been changed to work like "int" did
  4144 previously.  Potential INCOMPATIBILITY:
  4145   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4146   - of_nat_diff and of_nat_mult are no longer default simp rules
  4147 
  4148 * Method "algebra" solves polynomial equations over (semi)rings using
  4149 Groebner bases. The (semi)ring structure is defined by locales and the
  4150 tool setup depends on that generic context. Installing the method for
  4151 a specific type involves instantiating the locale and possibly adding
  4152 declarations for computation on the coefficients.  The method is
  4153 already instantiated for natural numbers and for the axiomatic class
  4154 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4155 CALCULEMUS 2007 for the general principles underlying this
  4156 architecture of context-aware proof-tools.
  4157 
  4158 * Method "ferrack" implements quantifier elimination over
  4159 special-purpose dense linear orders using locales (analogous to
  4160 "algebra"). The method is already installed for class
  4161 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4162 rat, etc.
  4163 
  4164 * Former constant "List.op @" now named "List.append".  Use ML
  4165 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4166 circumvent possible incompatibilities when working on ML level.
  4167 
  4168 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4169 
  4170 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4171 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4172 
  4173 * New syntax for Haskell-like list comprehension (input only), eg.
  4174 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4175 
  4176 * The special syntax for function "filter" has changed from [x :
  4177 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4178 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4179 
  4180 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4181 defined on nat only, as an abbreviation for [a..<Suc b]
  4182 INCOMPATIBILITY.
  4183 
  4184 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4185 
  4186 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4187 
  4188 * New lemma collection field_simps (an extension of ring_simps) for
  4189 manipulating (in)equations involving division. Multiplies with all
  4190 denominators that can be proved to be non-zero (in equations) or
  4191 positive/negative (in inequations).
  4192 
  4193 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4194 have been improved and renamed to ring_simps, group_simps and
  4195 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4196 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4197 
  4198 * Theory Library/Commutative_Ring: switched from recdef to function
  4199 package; constants add, mul, pow now curried.  Infix syntax for
  4200 algebraic operations.
  4201 
  4202 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4203 INCOMPATIBILITY.
  4204 
  4205 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4206 INCOMPATIBILITY.
  4207 
  4208 * HOL/records: generalised field-update to take a function on the
  4209 field rather than the new value: r(|A := x|) is translated to A_update
  4210 (K x) r The K-combinator that is internally used is called K_record.
  4211 INCOMPATIBILITY: Usage of the plain update functions has to be
  4212 adapted.
  4213  
  4214 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4215 * x = 0, which are required for a semiring.  Richer structures do not
  4216 inherit from semiring_0 anymore, because this property is a theorem
  4217 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4218 there is more to prove, but this is mostly trivial.
  4219 
  4220 * Class "recpower" is generalized to arbitrary monoids, not just
  4221 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4222 commutativity or semiring properties additionally.
  4223 
  4224 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4225 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4226 better use 'abbreviation'.
  4227 
  4228 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4229 
  4230 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4231 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4232 significant changes for setting up numeral syntax for types:
  4233   - New constants Numeral.pred and Numeral.succ instead
  4234       of former Numeral.bin_pred and Numeral.bin_succ.
  4235   - Use integer operations instead of bin_add, bin_mult and so on.
  4236   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4237   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4238 
  4239 See src/HOL/Integ/IntArith.thy for an example setup.
  4240 
  4241 * Command 'normal_form' computes the normal form of a term that may
  4242 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4243 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4244 heavy-duty computations because the functions are compiled to ML
  4245 first.  Correspondingly, a method "normalization" is provided.  See
  4246 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4247 
  4248 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4249 25 like -->); output depends on the "iff" print_mode, the default is
  4250 "A = B" (with priority 50).
  4251 
  4252 * Relations less (<) and less_eq (<=) are also available on type bool.
  4253 Modified syntax to disallow nesting without explicit parentheses,
  4254 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4255 INCOMPATIBILITY.
  4256 
  4257 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4258 
  4259 * Relation composition operator "op O" now has precedence 75 and binds
  4260 stronger than union and intersection. INCOMPATIBILITY.
  4261 
  4262 * The old set interval syntax "{m..n(}" (and relatives) has been
  4263 removed.  Use "{m..<n}" (and relatives) instead.
  4264 
  4265 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4266 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4267 ``declare [[simproc del: neq]]''.
  4268 
  4269 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4270 True/False.
  4271 
  4272 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4273 
  4274 * Theorem setsum_mult renamed to setsum_right_distrib.
  4275 
  4276 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4277 ``rule'' method.
  4278 
  4279 * Reimplemented methods "sat" and "satx", with several improvements:
  4280 goals no longer need to be stated as "<prems> ==> False", equivalences
  4281 (i.e. "=" on type bool) are handled, variable names of the form
  4282 "lit_<n>" are no longer reserved, significant speedup.
  4283 
  4284 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4285 zChaff is still supported as well.
  4286 
  4287 * 'inductive' and 'datatype': provide projections of mutual rules,
  4288 bundled as foo_bar.inducts;
  4289 
  4290 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4291 Library.
  4292 
  4293 * Library: moved theory Accessible_Part to main HOL.
  4294 
  4295 * Library: added theory Coinductive_List of potentially infinite lists
  4296 as greatest fixed-point.
  4297 
  4298 * Library: added theory AssocList which implements (finite) maps as
  4299 association lists.
  4300 
  4301 * Method "evaluation" solves goals (i.e. a boolean expression)
  4302 efficiently by compiling it to ML.  The goal is "proved" (via an
  4303 oracle) if it evaluates to True.
  4304 
  4305 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4306 also when invoked by the simplifier.  This results in the Simplifier
  4307 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4308 Configuration option fast_arith_split_limit=0 recovers the old
  4309 behavior.
  4310 
  4311 * Support for hex (0x20) and binary (0b1001) numerals.
  4312 
  4313 * New method: reify eqs (t), where eqs are equations for an
  4314 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4315 parameter, computes a term s::'b and a list xs::'a list and proves the
  4316 theorem I xs s = t. This is also known as reification or quoting. The
  4317 resulting theorem is applied to the subgoal to substitute t with I xs
  4318 s.  If t is omitted, the subgoal itself is reified.
  4319 
  4320 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4321 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4322 where f is supposed to be a computable function (in the sense of code
  4323 generattion). The method uses reify to compute s and xs as above then
  4324 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4325 r and finally gets the theorem t = r, which is again applied to the
  4326 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4327 
  4328 * Reflection: Automatic reification now handels binding, an example is
  4329 available in src/HOL/ex/ReflectionEx.thy
  4330 
  4331 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4332 command 'statespace' that is similar to 'record', but introduces an
  4333 abstract specification based on the locale infrastructure instead of
  4334 HOL types.  This leads to extra flexibility in composing state spaces,
  4335 in particular multiple inheritance and renaming of components.
  4336 
  4337 
  4338 *** HOL-Complex ***
  4339 
  4340 * Hyperreal: Functions root and sqrt are now defined on negative real
  4341 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4342 Nonnegativity side conditions have been removed from many lemmas, so
  4343 that more subgoals may now be solved by simplification; potential
  4344 INCOMPATIBILITY.
  4345 
  4346 * Real: new type classes formalize real normed vector spaces and
  4347 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4348 and norm :: 'a => real.
  4349 
  4350 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4351 reals into other types. The overloaded constant Reals :: 'a set is now
  4352 defined as range of_real; potential INCOMPATIBILITY.
  4353 
  4354 * Real: proper support for ML code generation, including 'quickcheck'.
  4355 Reals are implemented as arbitrary precision rationals.
  4356 
  4357 * Hyperreal: Several constants that previously worked only for the
  4358 reals have been generalized, so they now work over arbitrary vector
  4359 spaces. Type annotations may need to be added in some cases; potential
  4360 INCOMPATIBILITY.
  4361 
  4362   Infinitesimal  :: ('a::real_normed_vector) star set
  4363   HFinite        :: ('a::real_normed_vector) star set
  4364   HInfinite      :: ('a::real_normed_vector) star set
  4365   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4366   monad          :: ('a::real_normed_vector) star => 'a star set
  4367   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4368   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4369   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4370   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4371   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4372   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4373   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4374   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4375   sgn            :: 'a::real_normed_vector => 'a
  4376   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4377 
  4378 * Complex: Some complex-specific constants are now abbreviations for
  4379 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4380 hnorm.  Other constants have been entirely removed in favor of the
  4381 polymorphic versions (INCOMPATIBILITY):
  4382 
  4383   approx        <-- capprox
  4384   HFinite       <-- CFinite
  4385   HInfinite     <-- CInfinite
  4386   Infinitesimal <-- CInfinitesimal
  4387   monad         <-- cmonad
  4388   galaxy        <-- cgalaxy
  4389   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4390   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4391   (ns)deriv     <-- (ns)cderiv
  4392 
  4393 
  4394 *** HOL-Algebra ***
  4395 
  4396 * Formalisation of ideals and the quotient construction over rings.
  4397 
  4398 * Order and lattice theory no longer based on records.
  4399 INCOMPATIBILITY.
  4400 
  4401 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4402 greatest_closed.  INCOMPATIBILITY.
  4403 
  4404 * Method algebra is now set up via an attribute.  For examples see
  4405 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4406 of algebraic structures.
  4407 
  4408 * Renamed theory CRing to Ring.
  4409 
  4410 
  4411 *** HOL-Nominal ***
  4412 
  4413 * Substantial, yet incomplete support for nominal datatypes (binding
  4414 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4415 src/HOL/Nominal/Examples.  Prospective users should consult
  4416 http://isabelle.in.tum.de/nominal/
  4417 
  4418 
  4419 *** ML ***
  4420 
  4421 * ML basics: just one true type int, which coincides with IntInf.int
  4422 (even on SML/NJ).
  4423 
  4424 * ML within Isar: antiquotations allow to embed statically-checked
  4425 formal entities in the source, referring to the context available at
  4426 compile-time.  For example:
  4427 
  4428 ML {* @{sort "{zero,one}"} *}
  4429 ML {* @{typ "'a => 'b"} *}
  4430 ML {* @{term "%x. x"} *}
  4431 ML {* @{prop "x == y"} *}
  4432 ML {* @{ctyp "'a => 'b"} *}
  4433 ML {* @{cterm "%x. x"} *}
  4434 ML {* @{cprop "x == y"} *}
  4435 ML {* @{thm asm_rl} *}
  4436 ML {* @{thms asm_rl} *}
  4437 ML {* @{type_name c} *}
  4438 ML {* @{type_syntax c} *}
  4439 ML {* @{const_name c} *}
  4440 ML {* @{const_syntax c} *}
  4441 ML {* @{context} *}
  4442 ML {* @{theory} *}
  4443 ML {* @{theory Pure} *}
  4444 ML {* @{theory_ref} *}
  4445 ML {* @{theory_ref Pure} *}
  4446 ML {* @{simpset} *}
  4447 ML {* @{claset} *}
  4448 ML {* @{clasimpset} *}
  4449 
  4450 The same works for sources being ``used'' within an Isar context.
  4451 
  4452 * ML in Isar: improved error reporting; extra verbosity with
  4453 ML_Context.trace enabled.
  4454 
  4455 * Pure/General/table.ML: the join operations now works via exceptions
  4456 DUP/SAME instead of type option. This is simpler in simple cases, and
  4457 admits slightly more efficient complex applications.
  4458 
  4459 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4460 use Context.generic instead of just theory.
  4461 
  4462 * Pure: datatype Context.generic joins theory/Proof.context and
  4463 provides some facilities for code that works in either kind of
  4464 context, notably GenericDataFun for uniform theory and proof data.
  4465 
  4466 * Pure: simplified internal attribute type, which is now always
  4467 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4468 local (Proof.context) attributes have been discontinued, while
  4469 minimizing code duplication. Thm.rule_attribute and
  4470 Thm.declaration_attribute build canonical attributes; see also structure
  4471 Context for further operations on Context.generic, notably
  4472 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4473 declarations and definitions.
  4474 
  4475 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4476 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4477 init only required for impure data. INCOMPATIBILITY: empty really need
  4478 to be empty (no dependencies on theory content!)
  4479 
  4480 * Pure/kernel: consts certification ignores sort constraints given in
  4481 signature declarations. (This information is not relevant to the
  4482 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4483 potential INCOMPATIBILITY.
  4484 
  4485 * Pure: axiomatic type classes are now purely definitional, with
  4486 explicit proofs of class axioms and super class relations performed
  4487 internally. See Pure/axclass.ML for the main internal interfaces --
  4488 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4489 AxClass.axiomatize_class/classrel/arity supersede
  4490 Sign.add_classes/classrel/arities.
  4491 
  4492 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4493 global/local versions on theory vs. Proof.context have been
  4494 discontinued; Attrib.syntax and Method.syntax have been adapted
  4495 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4496 attributes, methods, etc.
  4497 
  4498 * Pure: several functions of signature "... -> theory -> theory * ..."
  4499 have been reoriented to "... -> theory -> ... * theory" in order to
  4500 allow natural usage in combination with the ||>, ||>>, |-> and
  4501 fold_map combinators.
  4502 
  4503 * Pure: official theorem names (closed derivations) and additional
  4504 comments (tags) are now strictly separate.  Name hints -- which are
  4505 maintained as tags -- may be attached any time without affecting the
  4506 derivation.
  4507 
  4508 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4509 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4510 achieve the old behaviour.
  4511 
  4512 * Pure: the "Goal" constant is now called "prop", supporting a
  4513 slightly more general idea of ``protecting'' meta-level rule
  4514 statements.
  4515 
  4516 * Pure: Logic.(un)varify only works in a global context, which is now
  4517 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4518 Logic.legacy_(un)varify as temporary workaround.
  4519 
  4520 * Pure: structure Name provides scalable operations for generating
  4521 internal variable names, notably Name.variants etc.  This replaces
  4522 some popular functions from term.ML:
  4523 
  4524   Term.variant		->  Name.variant
  4525   Term.variantlist	->  Name.variant_list
  4526   Term.invent_names	->  Name.invent_list
  4527 
  4528 Note that low-level renaming rarely occurs in new code -- operations
  4529 from structure Variable are used instead (see below).
  4530 
  4531 * Pure: structure Variable provides fundamental operations for proper
  4532 treatment of fixed/schematic variables in a context.  For example,
  4533 Variable.import introduces fixes for schematics of given facts and
  4534 Variable.export reverses the effect (up to renaming) -- this replaces
  4535 various freeze_thaw operations.
  4536 
  4537 * Pure: structure Goal provides simple interfaces for
  4538 init/conclude/finish and tactical prove operations (replacing former
  4539 Tactic.prove).  Goal.prove is the canonical way to prove results
  4540 within a given context; Goal.prove_global is a degraded version for
  4541 theory level goals, including a global Drule.standard.  Note that
  4542 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4543 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4544 in a locale context).
  4545 
  4546 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4547 and type checking (Syntax.check_term etc.), with common combinations
  4548 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4549 which are considered legacy and await removal.
  4550 
  4551 * Pure/Syntax: generic interfaces for type unchecking
  4552 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4553 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4554 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4555 available for convenience, but refer to the very same operations using
  4556 a mere theory instead of a full context.
  4557 
  4558 * Isar: simplified treatment of user-level errors, using exception
  4559 ERROR of string uniformly.  Function error now merely raises ERROR,
  4560 without any side effect on output channels.  The Isar toplevel takes
  4561 care of proper display of ERROR exceptions.  ML code may use plain
  4562 handle/can/try; cat_error may be used to concatenate errors like this:
  4563 
  4564   ... handle ERROR msg => cat_error msg "..."
  4565 
  4566 Toplevel ML code (run directly or through the Isar toplevel) may be
  4567 embedded into the Isar toplevel with exception display/debug like
  4568 this:
  4569 
  4570   Isar.toplevel (fn () => ...)
  4571 
  4572 INCOMPATIBILITY, removed special transform_error facilities, removed
  4573 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4574 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4575 -- use plain ERROR instead.
  4576 
  4577 * Isar: theory setup now has type (theory -> theory), instead of a
  4578 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4579 
  4580 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4581 ProofContext.debug/verbose flags.
  4582 
  4583 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4584 theory before entering a proof state.  Transactions now always see a
  4585 quasi-functional intermediate checkpoint, both in interactive and
  4586 batch mode.
  4587 
  4588 * Isar: simplified interfaces for outer syntax.  Renamed
  4589 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4590 OuterSyntax.add_parsers -- this functionality is now included in
  4591 OuterSyntax.command etc.  INCOMPATIBILITY.
  4592 
  4593 * Simplifier: the simpset of a running simplification process now
  4594 contains a proof context (cf. Simplifier.the_context), which is the
  4595 very context that the initial simpset has been retrieved from (by
  4596 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4597 (solver, looper etc.) may depend on arbitrary proof data.
  4598 
  4599 * Simplifier.inherit_context inherits the proof context (plus the
  4600 local bounds) of the current simplification process; any simproc
  4601 etc. that calls the Simplifier recursively should do this!  Removed
  4602 former Simplifier.inherit_bounds, which is already included here --
  4603 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4604 specify an explicit context using Simplifier.context/theory_context.
  4605 
  4606 * Simplifier/Classical Reasoner: more abstract interfaces
  4607 change_simpset/claset for modifying the simpset/claset reference of a
  4608 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4609 INCOMPATIBILITY.
  4610 
  4611 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4612 "Trueprop" etc.
  4613 
  4614 
  4615 *** System ***
  4616 
  4617 * settings: the default heap location within ISABELLE_HOME_USER now
  4618 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4619 Isabelle installations.
  4620 
  4621 * isabelle-process: option -S (secure mode) disables some critical
  4622 operations, notably runtime compilation and evaluation of ML source
  4623 code.
  4624 
  4625 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4626 
  4627 * Support for parallel execution, using native multicore support of
  4628 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4629 independent theories, according to the given theory header
  4630 specifications. The maximum number of worker threads is specified via
  4631 usedir option -M or the "max-threads" setting in Proof General. A
  4632 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4633 to 6 on a 8-core machine.  User-code needs to observe certain
  4634 guidelines for thread-safe programming, see appendix A in the Isar
  4635 Implementation manual.
  4636 
  4637 
  4638 
  4639 New in Isabelle2005 (October 2005)
  4640 ----------------------------------
  4641 
  4642 *** General ***
  4643 
  4644 * Theory headers: the new header syntax for Isar theories is
  4645 
  4646   theory <name>
  4647   imports <theory1> ... <theoryN>
  4648   uses <file1> ... <fileM>
  4649   begin
  4650 
  4651 where the 'uses' part is optional.  The previous syntax
  4652 
  4653   theory <name> = <theory1> + ... + <theoryN>:
  4654 
  4655 will disappear in the next release.  Use isatool fixheaders to convert
  4656 existing theory files.  Note that there is no change in ancient
  4657 non-Isar theories now, but these will disappear soon.
  4658 
  4659 * Theory loader: parent theories can now also be referred to via
  4660 relative and absolute paths.
  4661 
  4662 * Command 'find_theorems' searches for a list of criteria instead of a
  4663 list of constants. Known criteria are: intro, elim, dest, name:string,
  4664 simp:term, and any term. Criteria can be preceded by '-' to select
  4665 theorems that do not match. Intro, elim, dest select theorems that
  4666 match the current goal, name:s selects theorems whose fully qualified
  4667 name contain s, and simp:term selects all simplification rules whose
  4668 lhs match term.  Any other term is interpreted as pattern and selects
  4669 all theorems matching the pattern. Available in ProofGeneral under
  4670 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4671 
  4672   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4673 
  4674 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4675 matching the current goal as introduction rule and not having "HOL."
  4676 in their name (i.e. not being defined in theory HOL).
  4677 
  4678 * Command 'thms_containing' has been discontinued in favour of
  4679 'find_theorems'; INCOMPATIBILITY.
  4680 
  4681 * Communication with Proof General is now 8bit clean, which means that
  4682 Unicode text in UTF-8 encoding may be used within theory texts (both
  4683 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4684 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4685 
  4686   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4687   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4688 
  4689 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4690 Classical Reasoner.  Typical big applications run around 2 times
  4691 faster.
  4692 
  4693 
  4694 *** Document preparation ***
  4695 
  4696 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4697 of raw sources.  Only those symbols that do not require additional
  4698 LaTeX packages (depending on comments in isabellesym.sty) are
  4699 displayed properly, everything else is left verbatim.  isatool display
  4700 and isatool print are used as front ends (these are subject to the
  4701 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4702 
  4703 * Command tags control specific markup of certain regions of text,
  4704 notably folding and hiding.  Predefined tags include "theory" (for
  4705 theory begin and end), "proof" for proof commands, and "ML" for
  4706 commands involving ML code; the additional tags "visible" and
  4707 "invisible" are unused by default.  Users may give explicit tag
  4708 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4709 interpretation of tags is determined by the LaTeX job during document
  4710 preparation: see option -V of isatool usedir, or options -n and -t of
  4711 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4712 \isadroptag.
  4713 
  4714 Several document versions may be produced at the same time via isatool
  4715 usedir (the generated index.html will link all of them).  Typical
  4716 specifications include ''-V document=theory,proof,ML'' to present
  4717 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4718 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4719 these parts without any formal replacement text.  The Isabelle site
  4720 default settings produce ''document'' and ''outline'' versions as
  4721 specified above.
  4722 
  4723 * Several new antiquotations:
  4724 
  4725   @{term_type term} prints a term with its type annotated;
  4726 
  4727   @{typeof term} prints the type of a term;
  4728 
  4729   @{const const} is the same as @{term const}, but checks that the
  4730   argument is a known logical constant;
  4731 
  4732   @{term_style style term} and @{thm_style style thm} print a term or
  4733   theorem applying a "style" to it
  4734 
  4735   @{ML text}
  4736 
  4737 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4738 definitions, equations, inequations etc., 'concl' printing only the
  4739 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4740 to print the specified premise.  TermStyle.add_style provides an ML
  4741 interface for introducing further styles.  See also the "LaTeX Sugar"
  4742 document practical applications.  The ML antiquotation prints
  4743 type-checked ML expressions verbatim.
  4744 
  4745 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4746 and 'text' support optional locale specification '(in loc)', which
  4747 specifies the default context for interpreting antiquotations.  For
  4748 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4749 
  4750 * Option 'locale=NAME' of antiquotations specifies an alternative
  4751 context interpreting the subsequent argument.  For example: @{thm
  4752 [locale=lattice] inf_assoc}.
  4753 
  4754 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4755 a proof context.
  4756 
  4757 * Proper output of antiquotations for theory commands involving a
  4758 proof context (such as 'locale' or 'theorem (in loc) ...').
  4759 
  4760 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4761 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4762 
  4763 * isatool usedir: new option -C (default true) controls whether option
  4764 -D should include a copy of the original document directory; -C false
  4765 prevents unwanted effects such as copying of administrative CVS data.
  4766 
  4767 
  4768 *** Pure ***
  4769 
  4770 * Considerably improved version of 'constdefs' command.  Now performs
  4771 automatic type-inference of declared constants; additional support for
  4772 local structure declarations (cf. locales and HOL records), see also
  4773 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4774 sequential dependencies of definitions within a single 'constdefs'
  4775 section; moreover, the declared name needs to be an identifier.  If
  4776 all fails, consider to fall back on 'consts' and 'defs' separately.
  4777 
  4778 * Improved indexed syntax and implicit structures.  First of all,
  4779 indexed syntax provides a notational device for subscripted
  4780 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4781 expressions.  Secondly, in a local context with structure
  4782 declarations, number indexes \<^sub>n or the empty index (default
  4783 number 1) refer to a certain fixed variable implicitly; option
  4784 show_structs controls printing of implicit structures.  Typical
  4785 applications of these concepts involve record types and locales.
  4786 
  4787 * New command 'no_syntax' removes grammar declarations (and
  4788 translations) resulting from the given syntax specification, which is
  4789 interpreted in the same manner as for the 'syntax' command.
  4790 
  4791 * 'Advanced' translation functions (parse_translation etc.) may depend
  4792 on the signature of the theory context being presently used for
  4793 parsing/printing, see also isar-ref manual.
  4794 
  4795 * Improved 'oracle' command provides a type-safe interface to turn an
  4796 ML expression of type theory -> T -> term into a primitive rule of
  4797 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4798 is already included here); see also FOL/ex/IffExample.thy;
  4799 INCOMPATIBILITY.
  4800 
  4801 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4802 before); "cI" is no longer bound, use "c.intro" instead.
  4803 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4804 axclasses vs. locales.
  4805 
  4806 * Improved internal renaming of symbolic identifiers -- attach primes
  4807 instead of base 26 numbers.
  4808 
  4809 * New flag show_question_marks controls printing of leading question
  4810 marks in schematic variable names.
  4811 
  4812 * In schematic variable names, *any* symbol following \<^isub> or
  4813 \<^isup> is now treated as part of the base name.  For example, the
  4814 following works without printing of awkward ".0" indexes:
  4815 
  4816   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4817     by simp
  4818 
  4819 * Inner syntax includes (*(*nested*) comments*).
  4820 
  4821 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4822 annotations as "(00...)".
  4823 
  4824 * Clear separation of logical types and nonterminals, where the latter
  4825 may only occur in 'syntax' specifications or type abbreviations.
  4826 Before that distinction was only partially implemented via type class
  4827 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4828 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4829 exotic syntax specifications may require further adaption
  4830 (e.g. Cube/Cube.thy).
  4831 
  4832 * Removed obsolete type class "logic", use the top sort {} instead.
  4833 Note that non-logical types should be declared as 'nonterminals'
  4834 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4835 specifications.
  4836 
  4837 * Attributes 'induct' and 'cases': type or set names may now be
  4838 locally fixed variables as well.
  4839 
  4840 * Simplifier: can now control the depth to which conditional rewriting
  4841 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4842 Limit.
  4843 
  4844 * Simplifier: simplification procedures may now take the current
  4845 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4846 interface), which is very useful for calling the Simplifier
  4847 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4848 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4849 low-level mk_simproc no longer applies Logic.varify internally, to
  4850 allow for use in a context of fixed variables.
  4851 
  4852 * thin_tac now works even if the assumption being deleted contains !!
  4853 or ==>.  More generally, erule now works even if the major premise of
  4854 the elimination rule contains !! or ==>.
  4855 
  4856 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4857 
  4858 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4859 from Pure, which contains all common declarations already.  Both
  4860 theories are defined via plain Isabelle/Isar .thy files.
  4861 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4862 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4863 use isatool fixcpure to adapt your theory and ML sources.
  4864 
  4865 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4866 selections of theorems in named facts via index ranges.
  4867 
  4868 * 'print_theorems': in theory mode, really print the difference
  4869 wrt. the last state (works for interactive theory development only),
  4870 in proof mode print all local facts (cf. 'print_facts');
  4871 
  4872 * 'hide': option '(open)' hides only base names.
  4873 
  4874 * More efficient treatment of intermediate checkpoints in interactive
  4875 theory development.
  4876 
  4877 * Code generator is now invoked via code_module (incremental code
  4878 generation) and code_library (modular code generation, ML structures
  4879 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4880 must be quoted when used as identifiers.
  4881 
  4882 * New 'value' command for reading, evaluating and printing terms using
  4883 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4884 quoted when used as identifier.
  4885 
  4886 
  4887 *** Locales ***
  4888 
  4889 * New commands for the interpretation of locale expressions in
  4890 theories (1), locales (2) and proof contexts (3).  These generate
  4891 proof obligations from the expression specification.  After the
  4892 obligations have been discharged, theorems of the expression are added
  4893 to the theory, target locale or proof context.  The synopsis of the
  4894 commands is a follows:
  4895 
  4896   (1) interpretation expr inst
  4897   (2) interpretation target < expr
  4898   (3) interpret expr inst
  4899 
  4900 Interpretation in theories and proof contexts require a parameter
  4901 instantiation of terms from the current context.  This is applied to
  4902 specifications and theorems of the interpreted expression.
  4903 Interpretation in locales only permits parameter renaming through the
  4904 locale expression.  Interpretation is smart in that interpretations
  4905 that are active already do not occur in proof obligations, neither are
  4906 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4907 inspect active interpretations of a particular locale.  For details,
  4908 see the Isar Reference manual.  Examples can be found in
  4909 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4910 
  4911 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4912 'interpret' instead.
  4913 
  4914 * New context element 'constrains' for adding type constraints to
  4915 parameters.
  4916 
  4917 * Context expressions: renaming of parameters with syntax
  4918 redeclaration.
  4919 
  4920 * Locale declaration: 'includes' disallowed.
  4921 
  4922 * Proper static binding of attribute syntax -- i.e. types / terms /
  4923 facts mentioned as arguments are always those of the locale definition
  4924 context, independently of the context of later invocations.  Moreover,
  4925 locale operations (renaming and type / term instantiation) are applied
  4926 to attribute arguments as expected.
  4927 
  4928 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4929 actual attributes; rare situations may require Attrib.attribute to
  4930 embed those attributes into Attrib.src that lack concrete syntax.
  4931 Attribute implementations need to cooperate properly with the static
  4932 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4933 Attrib.XXX_thm etc. already do the right thing without further
  4934 intervention.  Only unusual applications -- such as "where" or "of"
  4935 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4936 on the context and the facts involved -- may have to assign parsed
  4937 values to argument tokens explicitly.
  4938 
  4939 * Changed parameter management in theorem generation for long goal
  4940 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4941 theorem statement in rare situations.
  4942 
  4943 * Locale inspection command 'print_locale' omits notes elements.  Use
  4944 'print_locale!' to have them included in the output.
  4945 
  4946 
  4947 *** Provers ***
  4948 
  4949 * Provers/hypsubst.ML: improved version of the subst method, for
  4950 single-step rewriting: it now works in bound variable contexts. New is
  4951 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4952 rewrite a different subterm than the original subst method, which is
  4953 still available as 'simplesubst'.
  4954 
  4955 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4956 and quasi orders.
  4957 
  4958 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4959 reflexive-transitive closure of relations.
  4960 
  4961 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4962 limit (previously hard-coded with a value of 20) user-definable.
  4963 
  4964 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4965 is peformed already.  Object-logics merely need to finish their
  4966 initial simpset configuration as before.  INCOMPATIBILITY.
  4967 
  4968 
  4969 *** HOL ***
  4970 
  4971 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4972 
  4973   syntax (epsilon)
  4974     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4975 
  4976 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4977 and x-symbol; use option '-m epsilon' to get it actually printed.
  4978 Moreover, the mathematically important symbolic identifier \<epsilon>
  4979 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4980 
  4981 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  4982 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  4983 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  4984 support corresponding Isar calculations.
  4985 
  4986 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  4987 instead of ":".
  4988 
  4989 * theory SetInterval: changed the syntax for open intervals:
  4990 
  4991   Old       New
  4992   {..n(}    {..<n}
  4993   {)n..}    {n<..}
  4994   {m..n(}   {m..<n}
  4995   {)m..n}   {m<..n}
  4996   {)m..n(}  {m<..<n}
  4997 
  4998 The old syntax is still supported but will disappear in the next
  4999 release.  For conversion use the following Emacs search and replace
  5000 patterns (these are not perfect but work quite well):
  5001 
  5002   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  5003   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  5004 
  5005 * Theory Commutative_Ring (in Library): method comm_ring for proving
  5006 equalities in commutative rings; method 'algebra' provides a generic
  5007 interface.
  5008 
  5009 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  5010 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  5011 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  5012 be a tuple pattern.
  5013 
  5014 Some new syntax forms are available:
  5015 
  5016   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  5017   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  5018   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  5019   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  5020 
  5021 The latter form "\<Sum>x < k. e" used to be based on a separate
  5022 function "Summation", which has been discontinued.
  5023 
  5024 * theory Finite_Set: in structured induction proofs, the insert case
  5025 is now 'case (insert x F)' instead of the old counterintuitive 'case
  5026 (insert F x)'.
  5027 
  5028 * The 'refute' command has been extended to support a much larger
  5029 fragment of HOL, including axiomatic type classes, constdefs and
  5030 typedefs, inductive datatypes and recursion.
  5031 
  5032 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  5033 Requires zChaff with proof generation to be installed.  See
  5034 HOL/ex/SAT_Examples.thy for examples.
  5035 
  5036 * Datatype induction via method 'induct' now preserves the name of the
  5037 induction variable. For example, when proving P(xs::'a list) by
  5038 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  5039 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  5040 in unstructured proof scripts.
  5041 
  5042 * Reworked implementation of records.  Improved scalability for
  5043 records with many fields, avoiding performance problems for type
  5044 inference. Records are no longer composed of nested field types, but
  5045 of nested extension types. Therefore the record type only grows linear
  5046 in the number of extensions and not in the number of fields.  The
  5047 top-level (users) view on records is preserved.  Potential
  5048 INCOMPATIBILITY only in strange cases, where the theory depends on the
  5049 old record representation. The type generated for a record is called
  5050 <record_name>_ext_type.
  5051 
  5052 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  5053 proofs triggered by a record definition or a simproc (if
  5054 quick_and_dirty is enabled).  Definitions of large records can take
  5055 quite long.
  5056 
  5057 New simproc record_upd_simproc for simplification of multiple record
  5058 updates enabled by default.  Moreover, trivial updates are also
  5059 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  5060 occasionally, since simplification is more powerful by default.
  5061 
  5062 * typedef: proper support for polymorphic sets, which contain extra
  5063 type-variables in the term.
  5064 
  5065 * Simplifier: automatically reasons about transitivity chains
  5066 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  5067 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  5068 old proofs break occasionally as simplification may now solve more
  5069 goals than previously.
  5070 
  5071 * Simplifier: converts x <= y into x = y if assumption y <= x is
  5072 present.  Works for all partial orders (class "order"), in particular
  5073 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  5074 just like y <= x.
  5075 
  5076 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  5077 bound variable or a constant then the let is unfolded.  Otherwise
  5078 first a is simplified to b, and then f b is simplified to g. If
  5079 possible we abstract b from g arriving at "let x = b in h x",
  5080 otherwise we unfold the let and arrive at g.  The simproc can be
  5081 enabled/disabled by the reference use_let_simproc.  Potential
  5082 INCOMPATIBILITY since simplification is more powerful by default.
  5083 
  5084 * Classical reasoning: the meson method now accepts theorems as arguments.
  5085 
  5086 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  5087 jobs to provide advice on the provability of subgoals.
  5088 
  5089 * Theory OrderedGroup and Ring_and_Field: various additions and
  5090 improvements to faciliate calculations involving equalities and
  5091 inequalities.
  5092 
  5093 The following theorems have been eliminated or modified
  5094 (INCOMPATIBILITY):
  5095 
  5096   abs_eq             now named abs_of_nonneg
  5097   abs_of_ge_0        now named abs_of_nonneg
  5098   abs_minus_eq       now named abs_of_nonpos
  5099   imp_abs_id         now named abs_of_nonneg
  5100   imp_abs_neg_id     now named abs_of_nonpos
  5101   mult_pos           now named mult_pos_pos
  5102   mult_pos_le        now named mult_nonneg_nonneg
  5103   mult_pos_neg_le    now named mult_nonneg_nonpos
  5104   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5105   mult_neg           now named mult_neg_neg
  5106   mult_neg_le        now named mult_nonpos_nonpos
  5107 
  5108 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5109      
  5110      zero_le_square
  5111      not_square_less_zero 
  5112 
  5113   The following lemmas have been deleted from Real/RealPow:
  5114   
  5115      realpow_zero_zero
  5116      realpow_two
  5117      realpow_less
  5118      zero_le_power
  5119      realpow_two_le
  5120      abs_realpow_two
  5121      realpow_two_abs     
  5122 
  5123 * Theory Parity: added rules for simplifying exponents.
  5124 
  5125 * Theory List:
  5126 
  5127 The following theorems have been eliminated or modified
  5128 (INCOMPATIBILITY):
  5129 
  5130   list_all_Nil       now named list_all.simps(1)
  5131   list_all_Cons      now named list_all.simps(2)
  5132   list_all_conv      now named list_all_iff
  5133   set_mem_eq         now named mem_iff
  5134 
  5135 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5136 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5137 
  5138 
  5139 *** HOL-Complex ***
  5140 
  5141 * Theory RealDef: better support for embedding natural numbers and
  5142 integers in the reals.
  5143 
  5144 The following theorems have been eliminated or modified
  5145 (INCOMPATIBILITY):
  5146 
  5147   exp_ge_add_one_self  now requires no hypotheses
  5148   real_of_int_add      reversed direction of equality (use [symmetric])
  5149   real_of_int_minus    reversed direction of equality (use [symmetric])
  5150   real_of_int_diff     reversed direction of equality (use [symmetric])
  5151   real_of_int_mult     reversed direction of equality (use [symmetric])
  5152 
  5153 * Theory RComplete: expanded support for floor and ceiling functions.
  5154 
  5155 * Theory Ln is new, with properties of the natural logarithm
  5156 
  5157 * Hyperreal: There is a new type constructor "star" for making
  5158 nonstandard types.  The old type names are now type synonyms:
  5159 
  5160   hypreal = real star
  5161   hypnat = nat star
  5162   hcomplex = complex star
  5163 
  5164 * Hyperreal: Many groups of similarly-defined constants have been
  5165 replaced by polymorphic versions (INCOMPATIBILITY):
  5166 
  5167   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5168 
  5169   starset      <-- starsetNat, starsetC
  5170   *s*          <-- *sNat*, *sc*
  5171   starset_n    <-- starsetNat_n, starsetC_n
  5172   *sn*         <-- *sNatn*, *scn*
  5173   InternalSets <-- InternalNatSets, InternalCSets
  5174 
  5175   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5176   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5177   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5178   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5179   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5180 
  5181 * Hyperreal: Many type-specific theorems have been removed in favor of
  5182 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5183 
  5184   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5185   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5186   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5187   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5188   right_minus <-- hypreal_add_minus
  5189   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5190   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5191   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5192   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5193   mult_1_right <-- hcomplex_mult_one_right
  5194   mult_zero_left <-- hcomplex_mult_zero_left
  5195   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5196   right_distrib <-- hypnat_add_mult_distrib2
  5197   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5198   right_inverse <-- hypreal_mult_inverse
  5199   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5200   order_refl <-- {hypreal,hypnat}_le_refl
  5201   order_trans <-- {hypreal,hypnat}_le_trans
  5202   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5203   order_less_le <-- {hypreal,hypnat}_less_le
  5204   linorder_linear <-- {hypreal,hypnat}_le_linear
  5205   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5206   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5207   add_nonneg_nonneg <-- hypreal_le_add_order
  5208 
  5209 * Hyperreal: Separate theorems having to do with type-specific
  5210 versions of constants have been merged into theorems that apply to the
  5211 new polymorphic constants (INCOMPATIBILITY):
  5212 
  5213   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5214   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5215   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5216   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5217   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5218   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5219   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5220   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5221   STAR_diff <-- {STAR,STARC}_diff
  5222   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5223     STARC_hcomplex_of_complex}_image_subset
  5224   starset_n_Un <-- starset{Nat,C}_n_Un
  5225   starset_n_Int <-- starset{Nat,C}_n_Int
  5226   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5227   starset_n_diff <-- starset{Nat,C}_n_diff
  5228   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5229   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5230   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5231   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5232   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5233   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5234   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5235   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5236   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5237   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5238   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5239   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5240   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5241   starfun_diff <-- starfun{C,RC,CR}_diff
  5242   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5243   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5244   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5245   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5246   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5247   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5248   starfun_Id <-- starfunC_Id
  5249   starfun_approx <-- starfun{Nat,CR}_approx
  5250   starfun_capprox <-- starfun{C,RC}_capprox
  5251   starfun_abs <-- starfunNat_rabs
  5252   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5253   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5254   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5255   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5256   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5257   starfun_add_approx <-- starfunCR_add_approx
  5258   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5259   starfun_divide <-- starfun{C,CR,RC}_divide
  5260   starfun_n <-- starfun{Nat,C}_n
  5261   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5262   starfun_n_add <-- starfun{Nat,C}_n_add
  5263   starfun_n_add_minus <-- starfunNat_n_add_minus
  5264   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5265   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5266   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5267 
  5268   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5269   star_n_minus <-- {hypreal,hcomplex}_minus
  5270   star_n_diff <-- {hypreal,hcomplex}_diff
  5271   star_n_mult <-- {hypreal,hcomplex}_mult
  5272   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5273   star_n_le <-- {hypreal,hypnat}_le
  5274   star_n_less <-- {hypreal,hypnat}_less
  5275   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5276   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5277   star_n_abs <-- hypreal_hrabs
  5278   star_n_divide <-- hcomplex_divide
  5279 
  5280   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5281   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5282   star_of_diff <-- hypreal_of_real_diff
  5283   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5284   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5285   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5286   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5287   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5288   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5289   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5290   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5291   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5292   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5293   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5294   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5295   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5296   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5297   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5298   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5299   star_of_power <-- hypreal_of_real_power
  5300   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5301 
  5302 * Hyperreal: new method "transfer" that implements the transfer
  5303 principle of nonstandard analysis. With a subgoal that mentions
  5304 nonstandard types like "'a star", the command "apply transfer"
  5305 replaces it with an equivalent one that mentions only standard types.
  5306 To be successful, all free variables must have standard types; non-
  5307 standard variables must have explicit universal quantifiers.
  5308 
  5309 * Hyperreal: A theory of Taylor series.
  5310 
  5311 
  5312 *** HOLCF ***
  5313 
  5314 * Discontinued special version of 'constdefs' (which used to support
  5315 continuous functions) in favor of the general Pure one with full
  5316 type-inference.
  5317 
  5318 * New simplification procedure for solving continuity conditions; it
  5319 is much faster on terms with many nested lambda abstractions (cubic
  5320 instead of exponential time).
  5321 
  5322 * New syntax for domain package: selector names are now optional.
  5323 Parentheses should be omitted unless argument is lazy, for example:
  5324 
  5325   domain 'a stream = cons "'a" (lazy "'a stream")
  5326 
  5327 * New command 'fixrec' for defining recursive functions with pattern
  5328 matching; defining multiple functions with mutual recursion is also
  5329 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5330 sinr, or any data constructor defined by the domain package. The given
  5331 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5332 syntax and examples.
  5333 
  5334 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5335 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5336 but the proof obligation additionally includes an admissibility
  5337 requirement. The packages generate instances of class cpo or pcpo,
  5338 with continuity and strictness theorems for Rep and Abs.
  5339 
  5340 * HOLCF: Many theorems have been renamed according to a more standard naming
  5341 scheme (INCOMPATIBILITY):
  5342 
  5343   foo_inject:  "foo$x = foo$y ==> x = y"
  5344   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5345   foo_less:    "(foo$x << foo$y) = (x << y)"
  5346   foo_strict:  "foo$UU = UU"
  5347   foo_defined: "... ==> foo$x ~= UU"
  5348   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5349 
  5350 
  5351 *** ZF ***
  5352 
  5353 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5354 including the First Isomorphism Theorem (on quotienting by the kernel
  5355 of a homomorphism).
  5356 
  5357 * ZF/Simplifier: install second copy of type solver that actually
  5358 makes use of TC rules declared to Isar proof contexts (or locales);
  5359 the old version is still required for ML proof scripts.
  5360 
  5361 
  5362 *** Cube ***
  5363 
  5364 * Converted to Isar theory format; use locales instead of axiomatic
  5365 theories.
  5366 
  5367 
  5368 *** ML ***
  5369 
  5370 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5371 for ||>, ||>>, |>>,
  5372 
  5373 * Pure/library.ML no longer defines its own option datatype, but uses
  5374 that of the SML basis, which has constructors NONE and SOME instead of
  5375 None and Some, as well as exception Option.Option instead of OPTION.
  5376 The functions the, if_none, is_some, is_none have been adapted
  5377 accordingly, while Option.map replaces apsome.
  5378 
  5379 * Pure/library.ML: the exception LIST has been given up in favour of
  5380 the standard exceptions Empty and Subscript, as well as
  5381 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5382 superceded by the standard hd and tl functions etc.
  5383 
  5384 A number of basic list functions are no longer exported to the ML
  5385 toplevel, as they are variants of predefined functions.  The following
  5386 suggests how one can translate existing code:
  5387 
  5388     rev_append xs ys = List.revAppend (xs, ys)
  5389     nth_elem (i, xs) = List.nth (xs, i)
  5390     last_elem xs = List.last xs
  5391     flat xss = List.concat xss
  5392     seq fs = List.app fs
  5393     partition P xs = List.partition P xs
  5394     mapfilter f xs = List.mapPartial f xs
  5395 
  5396 * Pure/library.ML: several combinators for linear functional
  5397 transformations, notably reverse application and composition:
  5398 
  5399   x |> f                f #> g
  5400   (x, y) |-> f          f #-> g
  5401 
  5402 * Pure/library.ML: introduced/changed precedence of infix operators:
  5403 
  5404   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5405   infix 2 ?;
  5406   infix 3 o oo ooo oooo;
  5407   infix 4 ~~ upto downto;
  5408 
  5409 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5410 infix operators.
  5411 
  5412 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5413 fold_map support linear functional transformations and nesting.  For
  5414 example:
  5415 
  5416   fold f [x1, ..., xN] y =
  5417     y |> f x1 |> ... |> f xN
  5418 
  5419   (fold o fold) f [xs1, ..., xsN] y =
  5420     y |> fold f xs1 |> ... |> fold f xsN
  5421 
  5422   fold f [x1, ..., xN] =
  5423     f x1 #> ... #> f xN
  5424 
  5425   (fold o fold) f [xs1, ..., xsN] =
  5426     fold f xs1 #> ... #> fold f xsN
  5427 
  5428 * Pure/library.ML: the following selectors on type 'a option are
  5429 available:
  5430 
  5431   the:               'a option -> 'a  (*partial*)
  5432   these:             'a option -> 'a  where 'a = 'b list
  5433   the_default: 'a -> 'a option -> 'a
  5434   the_list:          'a option -> 'a list
  5435 
  5436 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5437 basic operations for association lists, following natural argument
  5438 order; moreover the explicit equality predicate passed here avoids
  5439 potentially expensive polymorphic runtime equality checks.
  5440 The old functions may be expressed as follows:
  5441 
  5442   assoc = uncurry (AList.lookup (op =))
  5443   assocs = these oo AList.lookup (op =)
  5444   overwrite = uncurry (AList.update (op =)) o swap
  5445 
  5446 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5447 
  5448   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5449   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5450 
  5451 replacing make_keylist and keyfilter (occassionally used)
  5452 Naive rewrites:
  5453 
  5454   make_keylist = AList.make
  5455   keyfilter = AList.find (op =)
  5456 
  5457 * eq_fst and eq_snd now take explicit equality parameter, thus
  5458   avoiding eqtypes. Naive rewrites:
  5459 
  5460     eq_fst = eq_fst (op =)
  5461     eq_snd = eq_snd (op =)
  5462 
  5463 * Removed deprecated apl and apr (rarely used).
  5464   Naive rewrites:
  5465 
  5466     apl (n, op) =>>= curry op n
  5467     apr (op, m) =>>= fn n => op (n, m)
  5468 
  5469 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5470 provides a reasonably efficient light-weight implementation of sets as
  5471 lists.
  5472 
  5473 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5474 few new operations; existing lookup and update are now curried to
  5475 follow natural argument order (for use with fold etc.);
  5476 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5477 
  5478 * Pure/General: output via the Isabelle channels of
  5479 writeln/warning/error etc. is now passed through Output.output, with a
  5480 hook for arbitrary transformations depending on the print_mode
  5481 (cf. Output.add_mode -- the first active mode that provides a output
  5482 function wins).  Already formatted output may be embedded into further
  5483 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5484 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5485 accommodate easy composition of diagnostic messages etc.  Programmers
  5486 rarely need to care about Output.output or Output.raw at all, with
  5487 some notable exceptions: Output.output is required when bypassing the
  5488 standard channels (writeln etc.), or in token translations to produce
  5489 properly formatted results; Output.raw is required when capturing
  5490 already output material that will eventually be presented to the user
  5491 a second time.  For the default print mode, both Output.output and
  5492 Output.raw have no effect.
  5493 
  5494 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5495 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5496 cumulative results are displayed at the end of a batch session.
  5497 
  5498 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5499 replaced by File.platform_path and File.shell_path (with appropriate
  5500 hooks).  This provides a clean interface for unusual systems where the
  5501 internal and external process view of file names are different.
  5502 
  5503 * Pure: more efficient orders for basic syntactic entities: added
  5504 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5505 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5506 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5507 orders now -- potential INCOMPATIBILITY for code that depends on a
  5508 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5509 Library.sort_strings on result).
  5510 
  5511 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5512 fold_types traverse types/terms from left to right, observing natural
  5513 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5514 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5515 
  5516 * Pure: name spaces have been refined, with significant changes of the
  5517 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5518 to extern(_table).  The plain name entry path is superceded by a
  5519 general 'naming' context, which also includes the 'policy' to produce
  5520 a fully qualified name and external accesses of a fully qualified
  5521 name; NameSpace.extend is superceded by context dependent
  5522 Sign.declare_name.  Several theory and proof context operations modify
  5523 the naming context.  Especially note Theory.restore_naming and
  5524 ProofContext.restore_naming to get back to a sane state; note that
  5525 Theory.add_path is no longer sufficient to recover from
  5526 Theory.absolute_path in particular.
  5527 
  5528 * Pure: new flags short_names (default false) and unique_names
  5529 (default true) for controlling output of qualified names.  If
  5530 short_names is set, names are printed unqualified.  If unique_names is
  5531 reset, the name prefix is reduced to the minimum required to achieve
  5532 the original result when interning again, even if there is an overlap
  5533 with earlier declarations.
  5534 
  5535 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5536 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5537 (useful for printing error messages).  INCOMPATIBILITY.
  5538 
  5539 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5540 Theory.theory are now identified, referring to the universal
  5541 Context.theory (see Pure/context.ML).  Actual signature and theory
  5542 content is managed as theory data.  The old code and interfaces were
  5543 spread over many files and structures; the new arrangement introduces
  5544 considerable INCOMPATIBILITY to gain more clarity:
  5545 
  5546   Context -- theory management operations (name, identity, inclusion,
  5547     parents, ancestors, merge, etc.), plus generic theory data;
  5548 
  5549   Sign -- logical signature and syntax operations (declaring consts,
  5550     types, etc.), plus certify/read for common entities;
  5551 
  5552   Theory -- logical theory operations (stating axioms, definitions,
  5553     oracles), plus a copy of logical signature operations (consts,
  5554     types, etc.); also a few basic management operations (Theory.copy,
  5555     Theory.merge, etc.)
  5556 
  5557 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5558 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5559 for convenience -- they merely return the theory.
  5560 
  5561 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5562 
  5563 * Pure: the Isar proof context type is already defined early in Pure
  5564 as Context.proof (note that ProofContext.context and Proof.context are
  5565 aliases, where the latter is the preferred name).  This enables other
  5566 Isabelle components to refer to that type even before Isar is present.
  5567 
  5568 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5569 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5570 any of these kinds.  For example, Sign.intern typeK is now
  5571 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5572 Theory.hide_types.  Also note that former
  5573 Theory.hide_classes/types/consts are now
  5574 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5575 internalize their arguments!  INCOMPATIBILITY.
  5576 
  5577 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5578 datatype thmref (with constructors Name and NameSelection) instead of
  5579 plain string -- INCOMPATIBILITY;
  5580 
  5581 * Pure: cases produced by proof methods specify options, where NONE
  5582 means to remove case bindings -- INCOMPATIBILITY in
  5583 (RAW_)METHOD_CASES.
  5584 
  5585 * Pure: the following operations retrieve axioms or theorems from a
  5586 theory node or theory hierarchy, respectively:
  5587 
  5588   Theory.axioms_of: theory -> (string * term) list
  5589   Theory.all_axioms_of: theory -> (string * term) list
  5590   PureThy.thms_of: theory -> (string * thm) list
  5591   PureThy.all_thms_of: theory -> (string * thm) list
  5592 
  5593 * Pure: print_tac now outputs the goal through the trace channel.
  5594 
  5595 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5596 Reference Toplevel.debug (default false) controls detailed printing
  5597 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5598 controls execution profiling -- set to 1 for time and 2 for space
  5599 (both increase the runtime).
  5600 
  5601 * Isar session: The initial use of ROOT.ML is now always timed,
  5602 i.e. the log will show the actual process times, in contrast to the
  5603 elapsed wall-clock time that the outer shell wrapper produces.
  5604 
  5605 * Simplifier: improved handling of bound variables (nameless
  5606 representation, avoid allocating new strings).  Simprocs that invoke
  5607 the Simplifier recursively should use Simplifier.inherit_bounds to
  5608 avoid local name clashes.  Failure to do so produces warnings
  5609 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5610 for further details.
  5611 
  5612 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5613 bindings for all theorems stored within a given theory; this may help
  5614 in porting non-Isar theories to Isar ones, while keeping ML proof
  5615 scripts for the time being.
  5616 
  5617 * ML operator HTML.with_charset specifies the charset begin used for
  5618 generated HTML files.  For example:
  5619 
  5620   HTML.with_charset "utf-8" use_thy "Hebrew";
  5621   HTML.with_charset "utf-8" use_thy "Chinese";
  5622 
  5623 
  5624 *** System ***
  5625 
  5626 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5627 isabelle, isatool etc.).
  5628 
  5629 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5630 isatool doc, isatool mkdir, display_drafts etc.).
  5631 
  5632 * isatool usedir: option -f allows specification of the ML file to be
  5633 used by Isabelle; default is ROOT.ML.
  5634 
  5635 * New isatool version outputs the version identifier of the Isabelle
  5636 distribution being used.
  5637 
  5638 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5639 (containing Boolean satisfiability problems) into Isabelle/HOL
  5640 theories.
  5641 
  5642 
  5643 
  5644 New in Isabelle2004 (April 2004)
  5645 --------------------------------
  5646 
  5647 *** General ***
  5648 
  5649 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5650   Replaces linorder.ML.
  5651 
  5652 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5653   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5654   (\<a>...\<z>), are now considered normal letters, and can therefore
  5655   be used anywhere where an ASCII letter (a...zA...Z) has until
  5656   now. COMPATIBILITY: This obviously changes the parsing of some
  5657   terms, especially where a symbol has been used as a binder, say
  5658   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5659   as an identifier.  Fix it by inserting a space around former
  5660   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5661   existing theory and ML files.
  5662 
  5663 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5664 
  5665 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5666   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5667   a normal (but invisible) letter. For multiple letter subscripts repeat
  5668   \<^isub> like this: x\<^isub>1\<^isub>2.
  5669 
  5670 * Pure: There are now sub-/superscripts that can span more than one
  5671   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5672   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5673   superscript. The new control characters are not identifier parts.
  5674 
  5675 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5676   content of "..." to the latex file instead of \isacntrl... . The "..."
  5677   may consist of any printable characters excluding the end bracket >.
  5678 
  5679 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5680   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5681   declare constants "final", which prevents their being given a definition
  5682   later.  It is useful for constants whose behaviour is fixed axiomatically
  5683   rather than definitionally, such as the meta-logic connectives.
  5684 
  5685 * Pure: 'instance' now handles general arities with general sorts
  5686   (i.e. intersections of classes),
  5687 
  5688 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5689   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5690   It can be changed to alter the colors/layout of generated pages.
  5691 
  5692 
  5693 *** Isar ***
  5694 
  5695 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5696   cut_tac, subgoal_tac and thin_tac:
  5697   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5698     locales are no longer forced to write Isar proof scripts.
  5699     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5700     emulations.
  5701   - INCOMPATIBILITY: names of variables to be instantiated may no
  5702     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5703     This is consistent with the instantiation attribute "where".
  5704 
  5705 * Attributes "where" and "of":
  5706   - Now take type variables of instantiated theorem into account when reading
  5707     the instantiation string.  This fixes a bug that caused instantiated
  5708     theorems to have too special types in some circumstances.
  5709   - "where" permits explicit instantiations of type variables.
  5710 
  5711 * Calculation commands "moreover" and "also" no longer interfere with
  5712   current facts ("this"), admitting arbitrary combinations with "then"
  5713   and derived forms.
  5714 
  5715 * Locales:
  5716   - Goal statements involving the context element "includes" no longer
  5717     generate theorems with internal delta predicates (those ending on
  5718     "_axioms") in the premise.
  5719     Resolve particular premise with <locale>.intro to obtain old form.
  5720   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5721     specification and "includes" elements in goal statement.
  5722   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5723     [intro?] and [elim?] (respectively) by default.
  5724   - Experimental command for instantiation of locales in proof contexts:
  5725         instantiate <label>[<attrs>]: <loc>
  5726     Instantiates locale <loc> and adds all its theorems to the current context
  5727     taking into account their attributes.  Label and attrs are optional
  5728     modifiers, like in theorem declarations.  If present, names of
  5729     instantiated theorems are qualified with <label>, and the attributes
  5730     <attrs> are applied after any attributes these theorems might have already.
  5731       If the locale has assumptions, a chained fact of the form
  5732     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5733     are derived.  The command does not support old-style locales declared
  5734     with "locale (open)".
  5735       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5736 
  5737 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5738   (Isar) contexts.
  5739 
  5740 
  5741 *** HOL ***
  5742 
  5743 * Proof import: new image HOL4 contains the imported library from
  5744   the HOL4 system with about 2500 theorems. It is imported by
  5745   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5746   can be used like any other Isabelle image.  See
  5747   HOL/Import/HOL/README for more information.
  5748 
  5749 * Simplifier:
  5750   - Much improved handling of linear and partial orders.
  5751     Reasoners for linear and partial orders are set up for type classes
  5752     "linorder" and "order" respectively, and are added to the default simpset
  5753     as solvers.  This means that the simplifier can build transitivity chains
  5754     to solve goals from the assumptions.
  5755   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5756     of blast or auto after simplification become unnecessary because the goal
  5757     is solved by simplification already.
  5758 
  5759 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5760     all proved in axiomatic type classes for semirings, rings and fields.
  5761 
  5762 * Numerics:
  5763   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5764     now formalized using the Ring_and_Field theory mentioned above.
  5765   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5766     than before, because now they are set up once in a generic manner.
  5767   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5768     Look for the general versions in Ring_and_Field (and Power if they concern
  5769     exponentiation).
  5770 
  5771 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5772 
  5773 * Records:
  5774   - Record types are now by default printed with their type abbreviation
  5775     instead of the list of all field types. This can be configured via
  5776     the reference "print_record_type_abbr".
  5777   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5778     (not enabled by default).
  5779   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5780     EX x. x = sel r to True (not enabled by default).
  5781   - Tactic "record_split_simp_tac" to split and simplify records added.
  5782 
  5783 * 'specification' command added, allowing for definition by
  5784   specification.  There is also an 'ax_specification' command that
  5785   introduces the new constants axiomatically.
  5786 
  5787 * arith(_tac) is now able to generate counterexamples for reals as well.
  5788 
  5789 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5790 
  5791 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5792   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5793 
  5794 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5795   matrix theory to linear programming.
  5796 
  5797 * Unions and Intersections:
  5798   The latex output syntax of UN and INT has been changed
  5799   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5800   i.e. the index formulae has become a subscript.
  5801   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5802 
  5803 * Unions and Intersections over Intervals:
  5804   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5805   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5806   like in normal math, and corresponding versions for < and for intersection.
  5807 
  5808 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5809   lexicographic dictonary ordering has been added as "lexord".
  5810 
  5811 * ML: the legacy theory structures Int and List have been removed. They had
  5812   conflicted with ML Basis Library structures having the same names.
  5813 
  5814 * 'refute' command added to search for (finite) countermodels.  Only works
  5815   for a fragment of HOL.  The installation of an external SAT solver is
  5816   highly recommended.  See "HOL/Refute.thy" for details.
  5817 
  5818 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5819   formulae under an assignment of free variables to random values.
  5820   In contrast to 'refute', it can deal with inductive datatypes,
  5821   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5822   for examples.
  5823 
  5824 
  5825 *** HOLCF ***
  5826 
  5827 * Streams now come with concatenation and are part of the HOLCF image
  5828 
  5829 
  5830 
  5831 New in Isabelle2003 (May 2003)
  5832 ------------------------------
  5833 
  5834 *** General ***
  5835 
  5836 * Provers/simplifier:
  5837 
  5838   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5839     Assumptions are now subject to complete mutual simplification,
  5840     not just from left to right. The simplifier now preserves
  5841     the order of assumptions.
  5842 
  5843     Potential INCOMPATIBILITY:
  5844 
  5845     -- simp sometimes diverges where the old version did
  5846        not, e.g. invoking simp on the goal
  5847 
  5848         [| P (f x); y = x; f x = f y |] ==> Q
  5849 
  5850        now gives rise to the infinite reduction sequence
  5851 
  5852         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5853 
  5854        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5855        kind of problem.
  5856 
  5857     -- Tactics combining classical reasoner and simplification (such as auto)
  5858        are also affected by this change, because many of them rely on
  5859        simp. They may sometimes diverge as well or yield a different numbers
  5860        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5861        in case of problems. Sometimes subsequent calls to the classical
  5862        reasoner will fail because a preceeding call to the simplifier too
  5863        eagerly simplified the goal, e.g. deleted redundant premises.
  5864 
  5865   - The simplifier trace now shows the names of the applied rewrite rules
  5866 
  5867   - You can limit the number of recursive invocations of the simplifier
  5868     during conditional rewriting (where the simplifie tries to solve the
  5869     conditions before applying the rewrite rule):
  5870     ML "simp_depth_limit := n"
  5871     where n is an integer. Thus you can force termination where previously
  5872     the simplifier would diverge.
  5873 
  5874   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5875 
  5876   - No longer aborts on failed congruence proof.  Instead, the
  5877     congruence is ignored.
  5878 
  5879 * Pure: New generic framework for extracting programs from constructive
  5880   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5881   as HOL/Extraction for some case studies.
  5882 
  5883 * Pure: The main goal of the proof state is no longer shown by default, only
  5884 the subgoals. This behaviour is controlled by a new flag.
  5885    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5886 (ML: Proof.show_main_goal).
  5887 
  5888 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5889 rules whose conclusion matches subgoal 1:
  5890       PG menu: Isabelle/Isar -> Show me -> matching rules
  5891 The rules are ordered by how closely they match the subgoal.
  5892 In particular, rules that solve a subgoal outright are displayed first
  5893 (or rather last, the way they are printed).
  5894 (ML: ProofGeneral.print_intros())
  5895 
  5896 * Pure: New flag trace_unify_fail causes unification to print
  5897 diagnostic information (PG: in trace buffer) when it fails. This is
  5898 useful for figuring out why single step proofs like rule, erule or
  5899 assumption failed.
  5900 
  5901 * Pure: Locale specifications now produce predicate definitions
  5902 according to the body of text (covering assumptions modulo local
  5903 definitions); predicate "loc_axioms" covers newly introduced text,
  5904 while "loc" is cumulative wrt. all included locale expressions; the
  5905 latter view is presented only on export into the global theory
  5906 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5907 on the old view without predicates;
  5908 
  5909 * Pure: predefined locales "var" and "struct" are useful for sharing
  5910 parameters (as in CASL, for example); just specify something like
  5911 ``var x + var y + struct M'' as import;
  5912 
  5913 * Pure: improved thms_containing: proper indexing of facts instead of
  5914 raw theorems; check validity of results wrt. current name space;
  5915 include local facts of proof configuration (also covers active
  5916 locales), cover fixed variables in index; may use "_" in term
  5917 specification; an optional limit for the number of printed facts may
  5918 be given (the default is 40);
  5919 
  5920 * Pure: disallow duplicate fact bindings within new-style theory files
  5921 (batch-mode only);
  5922 
  5923 * Provers: improved induct method: assumptions introduced by case
  5924 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5925 the goal statement); "foo" still refers to all facts collectively;
  5926 
  5927 * Provers: the function blast.overloaded has been removed: all constants
  5928 are regarded as potentially overloaded, which improves robustness in exchange
  5929 for slight decrease in efficiency;
  5930 
  5931 * Provers/linorder: New generic prover for transitivity reasoning over
  5932 linear orders.  Note: this prover is not efficient!
  5933 
  5934 * Isar: preview of problems to finish 'show' now produce an error
  5935 rather than just a warning (in interactive mode);
  5936 
  5937 
  5938 *** HOL ***
  5939 
  5940 * arith(_tac)
  5941 
  5942  - Produces a counter example if it cannot prove a goal.
  5943    Note that the counter example may be spurious if the goal is not a formula
  5944    of quantifier-free linear arithmetic.
  5945    In ProofGeneral the counter example appears in the trace buffer.
  5946 
  5947  - Knows about div k and mod k where k is a numeral of type nat or int.
  5948 
  5949  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5950    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5951    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5952 
  5953 * simp's arithmetic capabilities have been enhanced a bit: it now
  5954 takes ~= in premises into account (by performing a case split);
  5955 
  5956 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5957 are distributed over a sum of terms;
  5958 
  5959 * New tactic "trans_tac" and method "trans" instantiate
  5960 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5961 "<=", "<" and "=").
  5962 
  5963 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5964 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5965 
  5966 * 'typedef' command has new option "open" to suppress the set
  5967 definition;
  5968 
  5969 * functions Min and Max on finite sets have been introduced (theory
  5970 Finite_Set);
  5971 
  5972 * attribute [symmetric] now works for relations as well; it turns
  5973 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5974 
  5975 * induct over a !!-quantified statement (say !!x1..xn):
  5976   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5977 
  5978 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5979 %x. None. Warning: empty_def now refers to the previously hidden definition
  5980 of the empty set.
  5981 
  5982 * Algebra: formalization of classical algebra.  Intended as base for
  5983 any algebraic development in Isabelle.  Currently covers group theory
  5984 (up to Sylow's theorem) and ring theory (Universal Property of
  5985 Univariate Polynomials).  Contributions welcome;
  5986 
  5987 * GroupTheory: deleted, since its material has been moved to Algebra;
  5988 
  5989 * Complex: new directory of the complex numbers with numeric constants,
  5990 nonstandard complex numbers, and some complex analysis, standard and
  5991 nonstandard (Jacques Fleuriot);
  5992 
  5993 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  5994 
  5995 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  5996 Fleuriot);
  5997 
  5998 * Real/HahnBanach: updated and adapted to locales;
  5999 
  6000 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  6001 Gray and Kramer);
  6002 
  6003 * UNITY: added the Meier-Sanders theory of progress sets;
  6004 
  6005 * MicroJava: bytecode verifier and lightweight bytecode verifier
  6006 as abstract algorithms, instantiated to the JVM;
  6007 
  6008 * Bali: Java source language formalization. Type system, operational
  6009 semantics, axiomatic semantics. Supported language features:
  6010 classes, interfaces, objects,virtual methods, static methods,
  6011 static/instance fields, arrays, access modifiers, definite
  6012 assignment, exceptions.
  6013 
  6014 
  6015 *** ZF ***
  6016 
  6017 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  6018 universe, etc.);
  6019 
  6020 * Main ZF: virtually all theories converted to new-style format;
  6021 
  6022 
  6023 *** ML ***
  6024 
  6025 * Pure: Tactic.prove provides sane interface for internal proofs;
  6026 omits the infamous "standard" operation, so this is more appropriate
  6027 than prove_goalw_cterm in many situations (e.g. in simprocs);
  6028 
  6029 * Pure: improved error reporting of simprocs;
  6030 
  6031 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  6032 up simprocs;
  6033 
  6034 
  6035 *** Document preparation ***
  6036 
  6037 * uses \par instead of \\ for line breaks in theory text. This may
  6038 shift some page breaks in large documents. To get the old behaviour
  6039 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  6040 
  6041 * minimized dependencies of isabelle.sty and isabellesym.sty on
  6042 other packages
  6043 
  6044 * \<euro> now needs package babel/greek instead of marvosym (which
  6045 broke \Rightarrow)
  6046 
  6047 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  6048 textcomp package)
  6049 
  6050 
  6051 
  6052 New in Isabelle2002 (March 2002)
  6053 --------------------------------
  6054 
  6055 *** Document preparation ***
  6056 
  6057 * greatly simplified document preparation setup, including more
  6058 graceful interpretation of isatool usedir -i/-d/-D options, and more
  6059 instructive isatool mkdir; users should basically be able to get
  6060 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  6061 users may run a separate document processing stage manually like this:
  6062 "isatool usedir -D output HOL Test && isatool document Test/output";
  6063 
  6064 * theory dependency graph may now be incorporated into documents;
  6065 isatool usedir -g true will produce session_graph.eps/.pdf for use
  6066 with \includegraphics of LaTeX;
  6067 
  6068 * proper spacing of consecutive markup elements, especially text
  6069 blocks after section headings;
  6070 
  6071 * support bold style (for single symbols only), input syntax is like
  6072 this: "\<^bold>\<alpha>" or "\<^bold>A";
  6073 
  6074 * \<bullet> is now output as bold \cdot by default, which looks much
  6075 better in printed text;
  6076 
  6077 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  6078 note that these symbols are currently unavailable in Proof General /
  6079 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  6080 
  6081 * isatool latex no longer depends on changed TEXINPUTS, instead
  6082 isatool document copies the Isabelle style files to the target
  6083 location;
  6084 
  6085 
  6086 *** Isar ***
  6087 
  6088 * Pure/Provers: improved proof by cases and induction;
  6089   - 'case' command admits impromptu naming of parameters (such as
  6090     "case (Suc n)");
  6091   - 'induct' method divinates rule instantiation from the inductive
  6092     claim; no longer requires excessive ?P bindings for proper
  6093     instantiation of cases;
  6094   - 'induct' method properly enumerates all possibilities of set/type
  6095     rules; as a consequence facts may be also passed through *type*
  6096     rules without further ado;
  6097   - 'induct' method now derives symbolic cases from the *rulified*
  6098     rule (before it used to rulify cases stemming from the internal
  6099     atomized version); this means that the context of a non-atomic
  6100     statement becomes is included in the hypothesis, avoiding the
  6101     slightly cumbersome show "PROP ?case" form;
  6102   - 'induct' may now use elim-style induction rules without chaining
  6103     facts, using ``missing'' premises from the goal state; this allows
  6104     rules stemming from inductive sets to be applied in unstructured
  6105     scripts, while still benefitting from proper handling of non-atomic
  6106     statements; NB: major inductive premises need to be put first, all
  6107     the rest of the goal is passed through the induction;
  6108   - 'induct' proper support for mutual induction involving non-atomic
  6109     rule statements (uses the new concept of simultaneous goals, see
  6110     below);
  6111   - append all possible rule selections, but only use the first
  6112     success (no backtracking);
  6113   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  6114   - undeclared rule case names default to numbers 1, 2, 3, ...;
  6115   - added 'print_induct_rules' (covered by help item in recent Proof
  6116     General versions);
  6117   - moved induct/cases attributes to Pure, methods to Provers;
  6118   - generic method setup instantiated for FOL and HOL;
  6119 
  6120 * Pure: support multiple simultaneous goal statements, for example
  6121 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  6122 meta-level mechanism, this acts as if several individual goals had
  6123 been stated separately; in particular common proof methods need to be
  6124 repeated in order to cover all claims; note that a single elimination
  6125 step is *not* sufficient to establish the two conjunctions, so this
  6126 fails:
  6127 
  6128   assume "A & B" then have A and B ..   (*".." fails*)
  6129 
  6130 better use "obtain" in situations as above; alternative refer to
  6131 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  6132 
  6133 * Pure: proper integration with ``locales''; unlike the original
  6134 version by Florian Kammller, Isar locales package high-level proof
  6135 contexts rather than raw logical ones (e.g. we admit to include
  6136 attributes everywhere); operations on locales include merge and
  6137 rename; support for implicit arguments (``structures''); simultaneous
  6138 type-inference over imports and text; see also HOL/ex/Locales.thy for
  6139 some examples;
  6140 
  6141 * Pure: the following commands have been ``localized'', supporting a
  6142 target locale specification "(in name)": 'lemma', 'theorem',
  6143 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  6144 stored both within the locale and at the theory level (exported and
  6145 qualified by the locale name);
  6146 
  6147 * Pure: theory goals may now be specified in ``long'' form, with
  6148 ad-hoc contexts consisting of arbitrary locale elements. for example
  6149 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  6150 definitions may be given, too); the result is a meta-level rule with
  6151 the context elements being discharged in the obvious way;
  6152 
  6153 * Pure: new proof command 'using' allows to augment currently used
  6154 facts after a goal statement ('using' is syntactically analogous to
  6155 'apply', but acts on the goal's facts only); this allows chained facts
  6156 to be separated into parts given before and after a claim, as in
  6157 ``from a and b have C using d and e <proof>'';
  6158 
  6159 * Pure: renamed "antecedent" case to "rule_context";
  6160 
  6161 * Pure: new 'judgment' command records explicit information about the
  6162 object-logic embedding (used by several tools internally); no longer
  6163 use hard-wired "Trueprop";
  6164 
  6165 * Pure: added 'corollary' command;
  6166 
  6167 * Pure: fixed 'token_translation' command;
  6168 
  6169 * Pure: removed obsolete 'exported' attribute;
  6170 
  6171 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  6172 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  6173 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  6174 
  6175 * Pure: method 'atomize' presents local goal premises as object-level
  6176 statements (atomic meta-level propositions); setup controlled via
  6177 rewrite rules declarations of 'atomize' attribute; example
  6178 application: 'induct' method with proper rule statements in improper
  6179 proof *scripts*;
  6180 
  6181 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  6182 now consider the syntactic context of assumptions, giving a better
  6183 chance to get type-inference of the arguments right (this is
  6184 especially important for locales);
  6185 
  6186 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  6187 mode;
  6188 
  6189 * Pure/obtain: the formal conclusion "thesis", being marked as
  6190 ``internal'', may no longer be reference directly in the text;
  6191 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  6192 situations;
  6193 
  6194 * Pure: generic 'sym' attribute which declares a rule both as pure
  6195 'elim?' and for the 'symmetric' operation;
  6196 
  6197 * Pure: marginal comments ``--'' may now occur just anywhere in the
  6198 text; the fixed correlation with particular command syntax has been
  6199 discontinued;
  6200 
  6201 * Pure: new method 'rules' is particularly well-suited for proof
  6202 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  6203 but often produces more compact proof terms with less detours;
  6204 
  6205 * Pure/Provers/classical: simplified integration with pure rule
  6206 attributes and methods; the classical "intro?/elim?/dest?"
  6207 declarations coincide with the pure ones; the "rule" method no longer
  6208 includes classically swapped intros; "intro" and "elim" methods no
  6209 longer pick rules from the context; also got rid of ML declarations
  6210 AddXIs/AddXEs/AddXDs; all of this has some potential for
  6211 INCOMPATIBILITY;
  6212 
  6213 * Provers/classical: attribute 'swapped' produces classical inversions
  6214 of introduction rules;
  6215 
  6216 * Provers/simplifier: 'simplified' attribute may refer to explicit
  6217 rules instead of full simplifier context; 'iff' attribute handles
  6218 conditional rules;
  6219 
  6220 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  6221 
  6222 * HOL: 'recdef' now fails on unfinished automated proofs, use
  6223 "(permissive)" option to recover old behavior;
  6224 
  6225 * HOL: 'inductive' no longer features separate (collective) attributes
  6226 for 'intros' (was found too confusing);
  6227 
  6228 * HOL: properly declared induction rules less_induct and
  6229 wf_induct_rule;
  6230