NEWS
author wenzelm
Thu Jun 09 17:46:25 2011 +0200 (2011-06-09)
changeset 43325 4384f4ae0574
parent 43319 048c7eea1a71
child 43527 1aacef7471c2
permissions -rw-r--r--
some attempts at robust \isaspacing so that \isa{...} can be used in section headings etc. (need to avoid `\? for some reason);
     1 Isabelle NEWS -- history user-relevant changes
     2 ==============================================
     3 
     4 New in this Isabelle version
     5 ----------------------------
     6 
     7 *** General ***
     8 
     9 * Theory loader: source files are identified by content via SHA1
    10 digests.  Discontinued former path/modtime identification and optional
    11 ISABELLE_FILE_IDENT plugin scripts.
    12 
    13 * Parallelization of nested Isar proofs is subject to
    14 Goal.parallel_proofs_threshold (default 100).  See also isabelle
    15 usedir option -Q.
    16 
    17 * Discontinued support for Poly/ML 5.2, which was the last version
    18 without proper multithreading and TimeLimit implementation.
    19 
    20 * Discontinued old lib/scripts/polyml-platform, which has been
    21 obsolete since Isabelle2009-2.
    22 
    23 * Theory loader: source files are exclusively located via the master
    24 directory of each theory node (where the .thy file itself resides).
    25 The global load path (such as src/HOL/Library) is has been
    26 discontinued.  INCOMPATIBILITY.
    27 
    28 * Various optional external tools are referenced more robustly and
    29 uniformly by explicit Isabelle settings as follows:
    30 
    31   ISABELLE_CSDP   (formerly CSDP_EXE)
    32   ISABELLE_GHC    (formerly EXEC_GHC or GHC_PATH)
    33   ISABELLE_OCAML  (formerly EXEC_OCAML)
    34   ISABELLE_SWIPL  (formerly EXEC_SWIPL)
    35   ISABELLE_YAP    (formerly EXEC_YAP)
    36 
    37 Note that automated detection from the file-system or search path has
    38 been discontinued.  INCOMPATIBILITY.
    39 
    40 * Name space: former unsynchronized references are now proper
    41 configuration options, with more conventional names:
    42 
    43   long_names   ~> names_long
    44   short_names  ~> names_short
    45   unique_names ~> names_unique
    46 
    47 Minor INCOMPATIBILITY, need to declare options in context like this:
    48 
    49   declare [[names_unique = false]]
    50 
    51 * Literal facts `prop` may contain dummy patterns, e.g. `_ = _`.  Note
    52 that the result needs to be unique, which means fact specifications
    53 may have to be refined after enriching a proof context.
    54 
    55 * Isabelle/Isar reference manual provides more formal references in
    56 syntax diagrams.
    57 
    58 
    59 *** HOL ***
    60 
    61 * Finite_Set.thy: more coherent development of fold_set locales:
    62 
    63     locale fun_left_comm ~> locale comp_fun_commute
    64     locale fun_left_comm_idem ~> locale comp_fun_idem
    65     
    66 Both use point-free characterisation; interpretation proofs may need adjustment.
    67 INCOMPATIBILITY.
    68 
    69 * Code generation:
    70   - theory Library/Code_Char_ord provides native ordering of characters
    71     in the target language.
    72     
    73 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
    74 
    75 * Nitpick:
    76   - Added "need" and "total_consts" options.
    77   - Reintroduced "show_skolems" option by popular demand.
    78   - Renamed attribute: nitpick_def ~> nitpick_unfold.
    79     INCOMPATIBILITY.
    80 
    81 * Sledgehammer:
    82   - sledgehammer available_provers ~> sledgehammer supported_provers
    83     INCOMPATIBILITY.
    84   - Added support for SNARK and ToFoF-E on SystemOnTPTP and for simply typed
    85     TPTP problems (TFF).
    86   - Added "type_sys", "max_mono_iters", and "max_new_mono_instances" options.
    87 
    88 * Metis:
    89   - Removed "metisF" -- use "metis" instead.
    90   - Obsoleted "metisFT" -- use "metis (full_types)" instead.
    91 
    92 * "try":
    93   - Added "simp:", "intro:", and "elim:" options.
    94 
    95 * Quickcheck:
    96   - Added "eval" option to evaluate terms for the found counterexample
    97     (currently only supported by the default (exhaustive) tester)
    98   - Added post-processing of terms to obtain readable counterexamples
    99     (currently only supported by the default (exhaustive) tester)
   100   - New counterexample generator quickcheck[narrowing] enables
   101     narrowing-based testing.
   102     It requires that the Glasgow Haskell compiler is installed and
   103     its location is known to Isabelle with the environment variable
   104     ISABELLE_GHC.
   105 
   106 * Function package: discontinued option "tailrec".
   107 INCOMPATIBILITY. Use partial_function instead.
   108 
   109 * HOL-Probability:
   110   - Caratheodory's extension lemma is now proved for ring_of_sets.
   111   - Infinite products of probability measures are now available.
   112   - Use extended reals instead of positive extended reals.
   113     INCOMPATIBILITY.
   114 
   115 
   116 *** Document preparation ***
   117 
   118 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
   119 isar-ref manual.
   120 
   121 * Localized \isabellestyle switch can be used within blocks or groups
   122 like this:
   123 
   124   \isabellestyle{it}  %preferred default
   125   {\isabellestylett @{text "typewriter stuff"}}
   126 
   127 * New term style "isub" as ad-hoc conversion of variables x1, y23 into
   128 subscripted form x\<^isub>1, y\<^isub>2\<^isub>3.
   129 
   130 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
   131 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
   132 
   133 
   134 *** ML ***
   135 
   136 * Isabelle_Process.is_active allows tools to check if the official
   137 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
   138 (better known as Proof General).
   139 
   140 * Structure Proof_Context follows standard naming scheme.  Old
   141 ProofContext is still available for some time as legacy alias.
   142 
   143 * Structure Timing provides various operations for timing; supersedes
   144 former start_timing/end_timing etc.
   145 
   146 * Path.print is the official way to show file-system paths to users
   147 (including quotes etc.).
   148 
   149 * Inner syntax: identifiers in parse trees of generic categories
   150 "logic", "aprop", "idt" etc. carry position information (disguised as
   151 type constraints).  Occasional INCOMPATIBILITY with non-compliant
   152 translations that choke on unexpected type constraints.  Positions can
   153 be stripped in ML translations via Syntax.strip_positions /
   154 Syntax.strip_positions_ast, or via the syntax constant
   155 "_strip_positions" within parse trees.  As last resort, positions can
   156 be disabled via the configuration option Syntax.positions, which is
   157 called "syntax_positions" in Isar attribute syntax.
   158 
   159 * Discontinued special status of various ML structures that contribute
   160 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
   161 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
   162 refer directly to Ast.Constant, Lexicon.is_identifier,
   163 Syntax_Trans.mk_binder_tr etc.
   164 
   165 * Typed print translation: discontinued show_sorts argument, which is
   166 already available via context of "advanced" translation.
   167 
   168 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
   169 goal states; body tactic needs to address all subgoals uniformly.
   170 
   171 * Slightly more special eq_list/eq_set, with shortcut involving
   172 pointer equality (assumes that eq relation is reflexive).
   173 
   174 * Classical tactics use proper Proof.context instead of historic types
   175 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
   176 operate directly on Proof.context.  Raw type claset retains its use as
   177 snapshot of the classical context, which can be recovered via
   178 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
   179 INCOMPATIBILITY, classical tactics and derived proof methods require
   180 proper Proof.context.
   181 
   182 
   183 
   184 New in Isabelle2011 (January 2011)
   185 ----------------------------------
   186 
   187 *** General ***
   188 
   189 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
   190 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
   191 useful tooltips and hyperlinks produced from its static analysis.  The
   192 bundled component provides an executable Isabelle tool that can be run
   193 like this:
   194 
   195   Isabelle2011/bin/isabelle jedit
   196 
   197 * Significantly improved Isabelle/Isar implementation manual.
   198 
   199 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
   200 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
   201 while the default heap location within that directory lacks that extra
   202 suffix.  This isolates multiple Isabelle installations from each
   203 other, avoiding problems with old settings in new versions.
   204 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
   205 
   206 * Source files are always encoded as UTF-8, instead of old-fashioned
   207 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   208 the following package declarations:
   209 
   210   \usepackage[utf8]{inputenc}
   211   \usepackage{textcomp}
   212 
   213 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   214 a Unicode character is treated as a single symbol, not a sequence of
   215 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   216 contain symbols without further backslash escapes, Unicode can now be
   217 used here as well.  Recall that Symbol.explode in ML provides a
   218 consistent view on symbols, while raw explode (or String.explode)
   219 merely give a byte-oriented representation.
   220 
   221 * Theory loader: source files are primarily located via the master
   222 directory of each theory node (where the .thy file itself resides).
   223 The global load path is still partially available as legacy feature.
   224 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   225 explicit paths, relatively to the theory.
   226 
   227 * Special treatment of ML file names has been discontinued.
   228 Historically, optional extensions .ML or .sml were added on demand --
   229 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   230 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   231 
   232 * Various options that affect pretty printing etc. are now properly
   233 handled within the context via configuration options, instead of
   234 unsynchronized references or print modes.  There are both ML Config.T
   235 entities and Isar declaration attributes to access these.
   236 
   237   ML (Config.T)                 Isar (attribute)
   238 
   239   eta_contract                  eta_contract
   240   show_brackets                 show_brackets
   241   show_sorts                    show_sorts
   242   show_types                    show_types
   243   show_question_marks           show_question_marks
   244   show_consts                   show_consts
   245   show_abbrevs                  show_abbrevs
   246 
   247   Syntax.ast_trace              syntax_ast_trace
   248   Syntax.ast_stat               syntax_ast_stat
   249   Syntax.ambiguity_level        syntax_ambiguity_level
   250 
   251   Goal_Display.goals_limit      goals_limit
   252   Goal_Display.show_main_goal   show_main_goal
   253 
   254   Method.rule_trace             rule_trace
   255 
   256   Thy_Output.display            thy_output_display
   257   Thy_Output.quotes             thy_output_quotes
   258   Thy_Output.indent             thy_output_indent
   259   Thy_Output.source             thy_output_source
   260   Thy_Output.break              thy_output_break
   261 
   262 Note that corresponding "..._default" references in ML may only be
   263 changed globally at the ROOT session setup, but *not* within a theory.
   264 The option "show_abbrevs" supersedes the former print mode
   265 "no_abbrevs" with inverted meaning.
   266 
   267 * More systematic naming of some configuration options.
   268 INCOMPATIBILITY.
   269 
   270   trace_simp  ~>  simp_trace
   271   debug_simp  ~>  simp_debug
   272 
   273 * Support for real valued configuration options, using simplistic
   274 floating-point notation that coincides with the inner syntax for
   275 float_token.
   276 
   277 * Support for real valued preferences (with approximative PGIP type):
   278 front-ends need to accept "pgint" values in float notation.
   279 INCOMPATIBILITY.
   280 
   281 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   282 DejaVu Sans.
   283 
   284 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   285 
   286 
   287 *** Pure ***
   288 
   289 * Command 'type_synonym' (with single argument) replaces somewhat
   290 outdated 'types', which is still available as legacy feature for some
   291 time.
   292 
   293 * Command 'nonterminal' (with 'and' separated list of arguments)
   294 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   295 
   296 * Command 'notepad' replaces former 'example_proof' for
   297 experimentation in Isar without any result.  INCOMPATIBILITY.
   298 
   299 * Locale interpretation commands 'interpret' and 'sublocale' accept
   300 lists of equations to map definitions in a locale to appropriate
   301 entities in the context of the interpretation.  The 'interpretation'
   302 command already provided this functionality.
   303 
   304 * Diagnostic command 'print_dependencies' prints the locale instances
   305 that would be activated if the specified expression was interpreted in
   306 the current context.  Variant "print_dependencies!" assumes a context
   307 without interpretations.
   308 
   309 * Diagnostic command 'print_interps' prints interpretations in proofs
   310 in addition to interpretations in theories.
   311 
   312 * Discontinued obsolete 'global' and 'local' commands to manipulate
   313 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   314 Sign.root_path and Sign.local_path may be applied directly where this
   315 feature is still required for historical reasons.
   316 
   317 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   318 'definition' instead.
   319 
   320 * The "prems" fact, which refers to the accidental collection of
   321 foundational premises in the context, is now explicitly marked as
   322 legacy feature and will be discontinued soon.  Consider using "assms"
   323 of the head statement or reference facts by explicit names.
   324 
   325 * Document antiquotations @{class} and @{type} print classes and type
   326 constructors.
   327 
   328 * Document antiquotation @{file} checks file/directory entries within
   329 the local file system.
   330 
   331 
   332 *** HOL ***
   333 
   334 * Coercive subtyping: functions can be declared as coercions and type
   335 inference will add them as necessary upon input of a term.  Theory
   336 Complex_Main declares real :: nat => real and real :: int => real as
   337 coercions. A coercion function f is declared like this:
   338 
   339   declare [[coercion f]]
   340 
   341 To lift coercions through type constructors (e.g. from nat => real to
   342 nat list => real list), map functions can be declared, e.g.
   343 
   344   declare [[coercion_map map]]
   345 
   346 Currently coercion inference is activated only in theories including
   347 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   348 the configuration option "coercion_enabled", e.g. it can be enabled in
   349 other theories like this:
   350 
   351   declare [[coercion_enabled]]
   352 
   353 * Command 'partial_function' provides basic support for recursive
   354 function definitions over complete partial orders.  Concrete instances
   355 are provided for i) the option type, ii) tail recursion on arbitrary
   356 types, and iii) the heap monad of Imperative_HOL.  See
   357 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   358 for examples.
   359 
   360 * Function package: f.psimps rules are no longer implicitly declared
   361 as [simp].  INCOMPATIBILITY.
   362 
   363 * Datatype package: theorems generated for executable equality (class
   364 "eq") carry proper names and are treated as default code equations.
   365 
   366 * Inductive package: now offers command 'inductive_simps' to
   367 automatically derive instantiated and simplified equations for
   368 inductive predicates, similar to 'inductive_cases'.
   369 
   370 * Command 'enriched_type' allows to register properties of the
   371 functorial structure of types.
   372 
   373 * Improved infrastructure for term evaluation using code generator
   374 techniques, in particular static evaluation conversions.
   375 
   376 * Code generator: Scala (2.8 or higher) has been added to the target
   377 languages.
   378 
   379 * Code generator: globbing constant expressions "*" and "Theory.*"
   380 have been replaced by the more idiomatic "_" and "Theory._".
   381 INCOMPATIBILITY.
   382 
   383 * Code generator: export_code without explicit file declaration prints
   384 to standard output.  INCOMPATIBILITY.
   385 
   386 * Code generator: do not print function definitions for case
   387 combinators any longer.
   388 
   389 * Code generator: simplification with rules determined with
   390 src/Tools/Code/code_simp.ML and method "code_simp".
   391 
   392 * Code generator for records: more idiomatic representation of record
   393 types.  Warning: records are not covered by ancient SML code
   394 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   395 rep_datatype declaration helps to succeed then:
   396 
   397   record 'a foo = ...
   398   ...
   399   rep_datatype foo_ext ...
   400 
   401 * Records: logical foundation type for records does not carry a
   402 '_type' suffix any longer (obsolete due to authentic syntax).
   403 INCOMPATIBILITY.
   404 
   405 * Quickcheck now by default uses exhaustive testing instead of random
   406 testing.  Random testing can be invoked by "quickcheck [random]",
   407 exhaustive testing by "quickcheck [exhaustive]".
   408 
   409 * Quickcheck instantiates polymorphic types with small finite
   410 datatypes by default. This enables a simple execution mechanism to
   411 handle quantifiers and function equality over the finite datatypes.
   412 
   413 * Quickcheck random generator has been renamed from "code" to
   414 "random".  INCOMPATIBILITY.
   415 
   416 * Quickcheck now has a configurable time limit which is set to 30
   417 seconds by default. This can be changed by adding [timeout = n] to the
   418 quickcheck command. The time limit for Auto Quickcheck is still set
   419 independently.
   420 
   421 * Quickcheck in locales considers interpretations of that locale for
   422 counter example search.
   423 
   424 * Sledgehammer:
   425   - Added "smt" and "remote_smt" provers based on the "smt" proof
   426     method. See the Sledgehammer manual for details ("isabelle doc
   427     sledgehammer").
   428   - Renamed commands:
   429     sledgehammer atp_info ~> sledgehammer running_provers
   430     sledgehammer atp_kill ~> sledgehammer kill_provers
   431     sledgehammer available_atps ~> sledgehammer available_provers
   432     INCOMPATIBILITY.
   433   - Renamed options:
   434     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   435     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   436     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   437     (and "ms" and "min" are no longer supported)
   438     INCOMPATIBILITY.
   439 
   440 * Nitpick:
   441   - Renamed options:
   442     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   443     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   444     INCOMPATIBILITY.
   445   - Added support for partial quotient types.
   446   - Added local versions of the "Nitpick.register_xxx" functions.
   447   - Added "whack" option.
   448   - Allow registration of quotient types as codatatypes.
   449   - Improved "merge_type_vars" option to merge more types.
   450   - Removed unsound "fast_descrs" option.
   451   - Added custom symmetry breaking for datatypes, making it possible to reach
   452     higher cardinalities.
   453   - Prevent the expansion of too large definitions.
   454 
   455 * Proof methods "metis" and "meson" now have configuration options
   456 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   457 to diagnose these tools. E.g.
   458 
   459     using [[metis_trace = true]]
   460 
   461 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   462 manually as command 'solve_direct'.
   463 
   464 * The default SMT solver Z3 must be enabled explicitly (due to
   465 licensing issues) by setting the environment variable
   466 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   467 commercial applications, the SMT solver CVC3 is provided as fall-back;
   468 changing the SMT solver is done via the configuration option
   469 "smt_solver".
   470 
   471 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   472 i.e. "remote_cvc3" and "remote_z3".
   473 
   474 * Added basic SMT support for datatypes, records, and typedefs using
   475 the oracle mode (no proofs).  Direct support of pairs has been dropped
   476 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   477 support for a similar behavior).  Minor INCOMPATIBILITY.
   478 
   479 * Changed SMT configuration options:
   480   - Renamed:
   481     z3_proofs ~> smt_oracle (with inverted meaning)
   482     z3_trace_assms ~> smt_trace_used_facts
   483     INCOMPATIBILITY.
   484   - Added:
   485     smt_verbose
   486     smt_random_seed
   487     smt_datatypes
   488     smt_infer_triggers
   489     smt_monomorph_limit
   490     cvc3_options
   491     remote_cvc3_options
   492     remote_z3_options
   493     yices_options
   494 
   495 * Boogie output files (.b2i files) need to be declared in the theory
   496 header.
   497 
   498 * Simplification procedure "list_to_set_comprehension" rewrites list
   499 comprehensions applied to List.set to set comprehensions.  Occasional
   500 INCOMPATIBILITY, may be deactivated like this:
   501 
   502   declare [[simproc del: list_to_set_comprehension]]
   503 
   504 * Removed old version of primrec package.  INCOMPATIBILITY.
   505 
   506 * Removed simplifier congruence rule of "prod_case", as has for long
   507 been the case with "split".  INCOMPATIBILITY.
   508 
   509 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   510 
   511 * Removed [split_format ... and ... and ...] version of
   512 [split_format].  Potential INCOMPATIBILITY.
   513 
   514 * Predicate "sorted" now defined inductively, with nice induction
   515 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   516 
   517 * Constant "contents" renamed to "the_elem", to free the generic name
   518 contents for other uses.  INCOMPATIBILITY.
   519 
   520 * Renamed class eq and constant eq (for code generation) to class
   521 equal and constant equal, plus renaming of related facts and various
   522 tuning.  INCOMPATIBILITY.
   523 
   524 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   525 
   526 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   527 INCOMPATIBILITY.
   528 
   529 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   530 avoid confusion with finite sets.  INCOMPATIBILITY.
   531 
   532 * Abandoned locales equiv, congruent and congruent2 for equivalence
   533 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   534 for congruent(2)).
   535 
   536 * Some previously unqualified names have been qualified:
   537 
   538   types
   539     bool ~> HOL.bool
   540     nat ~> Nat.nat
   541 
   542   constants
   543     Trueprop ~> HOL.Trueprop
   544     True ~> HOL.True
   545     False ~> HOL.False
   546     op & ~> HOL.conj
   547     op | ~> HOL.disj
   548     op --> ~> HOL.implies
   549     op = ~> HOL.eq
   550     Not ~> HOL.Not
   551     The ~> HOL.The
   552     All ~> HOL.All
   553     Ex ~> HOL.Ex
   554     Ex1 ~> HOL.Ex1
   555     Let ~> HOL.Let
   556     If ~> HOL.If
   557     Ball ~> Set.Ball
   558     Bex ~> Set.Bex
   559     Suc ~> Nat.Suc
   560     Pair ~> Product_Type.Pair
   561     fst ~> Product_Type.fst
   562     snd ~> Product_Type.snd
   563     curry ~> Product_Type.curry
   564     op : ~> Set.member
   565     Collect ~> Set.Collect
   566 
   567 INCOMPATIBILITY.
   568 
   569 * More canonical naming convention for some fundamental definitions:
   570 
   571     bot_bool_eq ~> bot_bool_def
   572     top_bool_eq ~> top_bool_def
   573     inf_bool_eq ~> inf_bool_def
   574     sup_bool_eq ~> sup_bool_def
   575     bot_fun_eq  ~> bot_fun_def
   576     top_fun_eq  ~> top_fun_def
   577     inf_fun_eq  ~> inf_fun_def
   578     sup_fun_eq  ~> sup_fun_def
   579 
   580 INCOMPATIBILITY.
   581 
   582 * More stylized fact names:
   583 
   584   expand_fun_eq ~> fun_eq_iff
   585   expand_set_eq ~> set_eq_iff
   586   set_ext       ~> set_eqI
   587   nat_number    ~> eval_nat_numeral
   588 
   589 INCOMPATIBILITY.
   590 
   591 * Refactoring of code-generation specific operations in theory List:
   592 
   593   constants
   594     null ~> List.null
   595 
   596   facts
   597     mem_iff ~> member_def
   598     null_empty ~> null_def
   599 
   600 INCOMPATIBILITY.  Note that these were not supposed to be used
   601 regularly unless for striking reasons; their main purpose was code
   602 generation.
   603 
   604 Various operations from the Haskell prelude are used for generating
   605 Haskell code.
   606 
   607 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   608 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   609 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   610 
   611 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   612 "*" and "+" respectively.  INCOMPATIBILITY.
   613 
   614 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   615 "Sum_Type.Plus" instead.
   616 
   617 * Constant "split" has been merged with constant "prod_case"; names of
   618 ML functions, facts etc. involving split have been retained so far,
   619 though.  INCOMPATIBILITY.
   620 
   621 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   622 instead.  INCOMPATIBILITY.
   623 
   624 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   625 INCOMPATIBILITY.
   626 
   627 * Former theory Library/Enum is now part of the HOL-Main image.
   628 INCOMPATIBILITY: all constants of the Enum theory now have to be
   629 referred to by its qualified name.
   630 
   631   enum    ~>  Enum.enum
   632   nlists  ~>  Enum.nlists
   633   product ~>  Enum.product
   634 
   635 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   636 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   637 INCOMPATIBILITY.
   638 
   639 * Theory Library/SetsAndFunctions has been split into
   640 Library/Function_Algebras and Library/Set_Algebras; canonical names
   641 for instance definitions for functions; various improvements.
   642 INCOMPATIBILITY.
   643 
   644 * Theory Library/Multiset provides stable quicksort implementation of
   645 sort_key.
   646 
   647 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   648 INCOMPATIBILITY.
   649 
   650 * Session Multivariate_Analysis: introduced a type class for euclidean
   651 space.  Most theorems are now stated in terms of euclidean spaces
   652 instead of finite cartesian products.
   653 
   654   types
   655     real ^ 'n ~>  'a::real_vector
   656               ~>  'a::euclidean_space
   657               ~>  'a::ordered_euclidean_space
   658         (depends on your needs)
   659 
   660   constants
   661      _ $ _        ~> _ $$ _
   662      \<chi> x. _  ~> \<chi>\<chi> x. _
   663      CARD('n)     ~> DIM('a)
   664 
   665 Also note that the indices are now natural numbers and not from some
   666 finite type. Finite cartesian products of euclidean spaces, products
   667 of euclidean spaces the real and complex numbers are instantiated to
   668 be euclidean_spaces.  INCOMPATIBILITY.
   669 
   670 * Session Probability: introduced pextreal as positive extended real
   671 numbers.  Use pextreal as value for measures.  Introduce the
   672 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   673 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   674 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   675 
   676 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   677 INCOMPATIBILITY.
   678 
   679 * Session SPARK (with image HOL-SPARK) provides commands to load and
   680 prove verification conditions generated by the SPARK Ada program
   681 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   682 
   683 
   684 *** HOL-Algebra ***
   685 
   686 * Theorems for additive ring operations (locale abelian_monoid and
   687 descendants) are generated by interpretation from their multiplicative
   688 counterparts.  Names (in particular theorem names) have the mandatory
   689 qualifier 'add'.  Previous theorem names are redeclared for
   690 compatibility.
   691 
   692 * Structure "int_ring" is now an abbreviation (previously a
   693 definition).  This fits more natural with advanced interpretations.
   694 
   695 
   696 *** HOLCF ***
   697 
   698 * The domain package now runs in definitional mode by default: The
   699 former command 'new_domain' is now called 'domain'.  To use the domain
   700 package in its original axiomatic mode, use 'domain (unsafe)'.
   701 INCOMPATIBILITY.
   702 
   703 * The new class "domain" is now the default sort.  Class "predomain"
   704 is an unpointed version of "domain". Theories can be updated by
   705 replacing sort annotations as shown below.  INCOMPATIBILITY.
   706 
   707   'a::type ~> 'a::countable
   708   'a::cpo  ~> 'a::predomain
   709   'a::pcpo ~> 'a::domain
   710 
   711 * The old type class "rep" has been superseded by class "domain".
   712 Accordingly, users of the definitional package must remove any
   713 "default_sort rep" declarations.  INCOMPATIBILITY.
   714 
   715 * The domain package (definitional mode) now supports unpointed
   716 predomain argument types, as long as they are marked 'lazy'. (Strict
   717 arguments must be in class "domain".) For example, the following
   718 domain definition now works:
   719 
   720   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   721 
   722 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   723 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   724 'a option, and 'a list.  Additionally, it configures fixrec and the
   725 domain package to work with these types.  For example:
   726 
   727   fixrec isInl :: "('a + 'b) u -> tr"
   728     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   729 
   730   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   731 
   732 * The "(permissive)" option of fixrec has been replaced with a
   733 per-equation "(unchecked)" option. See
   734 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
   735 
   736 * The "bifinite" class no longer fixes a constant "approx"; the class
   737 now just asserts that such a function exists.  INCOMPATIBILITY.
   738 
   739 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
   740 defines an embedding of type 'a defl into udom by default; instances
   741 of "bifinite" and "domain" classes are available in
   742 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
   743 
   744 * The syntax "REP('a)" has been replaced with "DEFL('a)".
   745 
   746 * The predicate "directed" has been removed.  INCOMPATIBILITY.
   747 
   748 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
   749 
   750 * The function "cprod_map" has been renamed to "prod_map".
   751 INCOMPATIBILITY.
   752 
   753 * The monadic bind operator on each powerdomain has new binder syntax
   754 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
   755 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
   756 
   757 * The infix syntax for binary union on each powerdomain has changed
   758 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
   759 syntax.  INCOMPATIBILITY.
   760 
   761 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
   762 still supported as an input translation.
   763 
   764 * Renamed some theorems (the original names are also still available).
   765 
   766   expand_fun_below   ~> fun_below_iff
   767   below_fun_ext      ~> fun_belowI
   768   expand_cfun_eq     ~> cfun_eq_iff
   769   ext_cfun           ~> cfun_eqI
   770   expand_cfun_below  ~> cfun_below_iff
   771   below_cfun_ext     ~> cfun_belowI
   772   cont2cont_Rep_CFun ~> cont2cont_APP
   773 
   774 * The Abs and Rep functions for various types have changed names.
   775 Related theorem names have also changed to match. INCOMPATIBILITY.
   776 
   777   Rep_CFun  ~> Rep_cfun
   778   Abs_CFun  ~> Abs_cfun
   779   Rep_Sprod ~> Rep_sprod
   780   Abs_Sprod ~> Abs_sprod
   781   Rep_Ssum  ~> Rep_ssum
   782   Abs_Ssum  ~> Abs_ssum
   783 
   784 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   785 been renamed to *_bottom_iff.  INCOMPATIBILITY.
   786 
   787 * Various changes to bisimulation/coinduction with domain package:
   788 
   789   - Definitions of "bisim" constants no longer mention definedness.
   790   - With mutual recursion, "bisim" predicate is now curried.
   791   - With mutual recursion, each type gets a separate coind theorem.
   792   - Variable names in bisim_def and coinduct rules have changed.
   793 
   794 INCOMPATIBILITY.
   795 
   796 * Case combinators generated by the domain package for type "foo" are
   797 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
   798 
   799 * Several theorems have been renamed to more accurately reflect the
   800 names of constants and types involved.  INCOMPATIBILITY.
   801 
   802   thelub_const    ~> lub_const
   803   lub_const       ~> is_lub_const
   804   thelubI         ~> lub_eqI
   805   is_lub_lub      ~> is_lubD2
   806   lubI            ~> is_lub_lub
   807   unique_lub      ~> is_lub_unique
   808   is_ub_lub       ~> is_lub_rangeD1
   809   lub_bin_chain   ~> is_lub_bin_chain
   810   lub_fun         ~> is_lub_fun
   811   thelub_fun      ~> lub_fun
   812   thelub_cfun     ~> lub_cfun
   813   thelub_Pair     ~> lub_Pair
   814   lub_cprod       ~> is_lub_prod
   815   thelub_cprod    ~> lub_prod
   816   minimal_cprod   ~> minimal_prod
   817   inst_cprod_pcpo ~> inst_prod_pcpo
   818   UU_I            ~> bottomI
   819   compact_UU      ~> compact_bottom
   820   deflation_UU    ~> deflation_bottom
   821   finite_deflation_UU ~> finite_deflation_bottom
   822 
   823 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
   824 
   825   sq_ord_less_eq_trans ~> below_eq_trans
   826   sq_ord_eq_less_trans ~> eq_below_trans
   827   refl_less            ~> below_refl
   828   trans_less           ~> below_trans
   829   antisym_less         ~> below_antisym
   830   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
   831   box_less             ~> box_below
   832   rev_trans_less       ~> rev_below_trans
   833   not_less2not_eq      ~> not_below2not_eq
   834   less_UU_iff          ~> below_UU_iff
   835   flat_less_iff        ~> flat_below_iff
   836   adm_less             ~> adm_below
   837   adm_not_less         ~> adm_not_below
   838   adm_compact_not_less ~> adm_compact_not_below
   839   less_fun_def         ~> below_fun_def
   840   expand_fun_less      ~> fun_below_iff
   841   less_fun_ext         ~> fun_belowI
   842   less_discr_def       ~> below_discr_def
   843   discr_less_eq        ~> discr_below_eq
   844   less_unit_def        ~> below_unit_def
   845   less_cprod_def       ~> below_prod_def
   846   prod_lessI           ~> prod_belowI
   847   Pair_less_iff        ~> Pair_below_iff
   848   fst_less_iff         ~> fst_below_iff
   849   snd_less_iff         ~> snd_below_iff
   850   expand_cfun_less     ~> cfun_below_iff
   851   less_cfun_ext        ~> cfun_belowI
   852   injection_less       ~> injection_below
   853   less_up_def          ~> below_up_def
   854   not_Iup_less         ~> not_Iup_below
   855   Iup_less             ~> Iup_below
   856   up_less              ~> up_below
   857   Def_inject_less_eq   ~> Def_below_Def
   858   Def_less_is_eq       ~> Def_below_iff
   859   spair_less_iff       ~> spair_below_iff
   860   less_sprod           ~> below_sprod
   861   spair_less           ~> spair_below
   862   sfst_less_iff        ~> sfst_below_iff
   863   ssnd_less_iff        ~> ssnd_below_iff
   864   fix_least_less       ~> fix_least_below
   865   dist_less_one        ~> dist_below_one
   866   less_ONE             ~> below_ONE
   867   ONE_less_iff         ~> ONE_below_iff
   868   less_sinlD           ~> below_sinlD
   869   less_sinrD           ~> below_sinrD
   870 
   871 
   872 *** FOL and ZF ***
   873 
   874 * All constant names are now qualified internally and use proper
   875 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
   876 
   877 
   878 *** ML ***
   879 
   880 * Antiquotation @{assert} inlines a function bool -> unit that raises
   881 Fail if the argument is false.  Due to inlining the source position of
   882 failed assertions is included in the error output.
   883 
   884 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
   885 text is in practice always evaluated with a stable theory checkpoint.
   886 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
   887 
   888 * Antiquotation @{theory A} refers to theory A from the ancestry of
   889 the current context, not any accidental theory loader state as before.
   890 Potential INCOMPATIBILITY, subtle change in semantics.
   891 
   892 * Syntax.pretty_priority (default 0) configures the required priority
   893 of pretty-printed output and thus affects insertion of parentheses.
   894 
   895 * Syntax.default_root (default "any") configures the inner syntax
   896 category (nonterminal symbol) for parsing of terms.
   897 
   898 * Former exception Library.UnequalLengths now coincides with
   899 ListPair.UnequalLengths.
   900 
   901 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
   902 main functionality is provided by structure Simplifier.
   903 
   904 * Renamed raw "explode" function to "raw_explode" to emphasize its
   905 meaning.  Note that internally to Isabelle, Symbol.explode is used in
   906 almost all situations.
   907 
   908 * Discontinued obsolete function sys_error and exception SYS_ERROR.
   909 See implementation manual for further details on exceptions in
   910 Isabelle/ML.
   911 
   912 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   913 meaning.
   914 
   915 * Renamed structure PureThy to Pure_Thy and moved most of its
   916 operations to structure Global_Theory, to emphasize that this is
   917 rarely-used global-only stuff.
   918 
   919 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
   920 instead (or tracing for high-volume output).
   921 
   922 * Configuration option show_question_marks only affects regular pretty
   923 printing of types and terms, not raw Term.string_of_vname.
   924 
   925 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
   926 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
   927 @{thms} for most purposes.
   928 
   929 * ML structure Unsynchronized is never opened, not even in Isar
   930 interaction mode as before.  Old Unsynchronized.set etc. have been
   931 discontinued -- use plain := instead.  This should be *rare* anyway,
   932 since modern tools always work via official context data, notably
   933 configuration options.
   934 
   935 * Parallel and asynchronous execution requires special care concerning
   936 interrupts.  Structure Exn provides some convenience functions that
   937 avoid working directly with raw Interrupt.  User code must not absorb
   938 interrupts -- intermediate handling (for cleanup etc.) needs to be
   939 followed by re-raising of the original exception.  Another common
   940 source of mistakes are "handle _" patterns, which make the meaning of
   941 the program subject to physical effects of the environment.
   942 
   943 
   944 
   945 New in Isabelle2009-2 (June 2010)
   946 ---------------------------------
   947 
   948 *** General ***
   949 
   950 * Authentic syntax for *all* logical entities (type classes, type
   951 constructors, term constants): provides simple and robust
   952 correspondence between formal entities and concrete syntax.  Within
   953 the parse tree / AST representations, "constants" are decorated by
   954 their category (class, type, const) and spelled out explicitly with
   955 their full internal name.
   956 
   957 Substantial INCOMPATIBILITY concerning low-level syntax declarations
   958 and translations (translation rules and translation functions in ML).
   959 Some hints on upgrading:
   960 
   961   - Many existing uses of 'syntax' and 'translations' can be replaced
   962     by more modern 'type_notation', 'notation' and 'abbreviation',
   963     which are independent of this issue.
   964 
   965   - 'translations' require markup within the AST; the term syntax
   966     provides the following special forms:
   967 
   968       CONST c   -- produces syntax version of constant c from context
   969       XCONST c  -- literally c, checked as constant from context
   970       c         -- literally c, if declared by 'syntax'
   971 
   972     Plain identifiers are treated as AST variables -- occasionally the
   973     system indicates accidental variables via the error "rhs contains
   974     extra variables".
   975 
   976     Type classes and type constructors are marked according to their
   977     concrete syntax.  Some old translations rules need to be written
   978     for the "type" category, using type constructor application
   979     instead of pseudo-term application of the default category
   980     "logic".
   981 
   982   - 'parse_translation' etc. in ML may use the following
   983     antiquotations:
   984 
   985       @{class_syntax c}   -- type class c within parse tree / AST
   986       @{term_syntax c}    -- type constructor c within parse tree / AST
   987       @{const_syntax c}   -- ML version of "CONST c" above
   988       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
   989 
   990   - Literal types within 'typed_print_translations', i.e. those *not*
   991     represented as pseudo-terms are represented verbatim.  Use @{class
   992     c} or @{type_name c} here instead of the above syntax
   993     antiquotations.
   994 
   995 Note that old non-authentic syntax was based on unqualified base
   996 names, so all of the above "constant" names would coincide.  Recall
   997 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
   998 diagnose syntax problems.
   999 
  1000 * Type constructors admit general mixfix syntax, not just infix.
  1001 
  1002 * Concrete syntax may be attached to local entities without a proof
  1003 body, too.  This works via regular mixfix annotations for 'fix',
  1004 'def', 'obtain' etc. or via the explicit 'write' command, which is
  1005 similar to the 'notation' command in theory specifications.
  1006 
  1007 * Discontinued unnamed infix syntax (legacy feature for many years) --
  1008 need to specify constant name and syntax separately.  Internal ML
  1009 datatype constructors have been renamed from InfixName to Infix etc.
  1010 Minor INCOMPATIBILITY.
  1011 
  1012 * Schematic theorem statements need to be explicitly markup as such,
  1013 via commands 'schematic_lemma', 'schematic_theorem',
  1014 'schematic_corollary'.  Thus the relevance of the proof is made
  1015 syntactically clear, which impacts performance in a parallel or
  1016 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  1017 
  1018 * Use of cumulative prems via "!" in some proof methods has been
  1019 discontinued (old legacy feature).
  1020 
  1021 * References 'trace_simp' and 'debug_simp' have been replaced by
  1022 configuration options stored in the context. Enabling tracing (the
  1023 case of debugging is similar) in proofs works via
  1024 
  1025   using [[trace_simp = true]]
  1026 
  1027 Tracing is then active for all invocations of the simplifier in
  1028 subsequent goal refinement steps. Tracing may also still be enabled or
  1029 disabled via the ProofGeneral settings menu.
  1030 
  1031 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  1032 'hide_fact' replace the former 'hide' KIND command.  Minor
  1033 INCOMPATIBILITY.
  1034 
  1035 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  1036 more efficient than combinations with -q1 or -q2.
  1037 
  1038 
  1039 *** Pure ***
  1040 
  1041 * Proofterms record type-class reasoning explicitly, using the
  1042 "unconstrain" operation internally.  This eliminates all sort
  1043 constraints from a theorem and proof, introducing explicit
  1044 OFCLASS-premises.  On the proof term level, this operation is
  1045 automatically applied at theorem boundaries, such that closed proofs
  1046 are always free of sort constraints.  INCOMPATIBILITY for tools that
  1047 inspect proof terms.
  1048 
  1049 * Local theory specifications may depend on extra type variables that
  1050 are not present in the result type -- arguments TYPE('a) :: 'a itself
  1051 are added internally.  For example:
  1052 
  1053   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  1054 
  1055 * Predicates of locales introduced by classes carry a mandatory
  1056 "class" prefix.  INCOMPATIBILITY.
  1057 
  1058 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  1059 
  1060 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  1061 'class' instead.
  1062 
  1063 * Command 'code_reflect' allows to incorporate generated ML code into
  1064 runtime environment; replaces immature code_datatype antiquotation.
  1065 INCOMPATIBILITY.
  1066 
  1067 * Code generator: simple concept for abstract datatypes obeying
  1068 invariants.
  1069 
  1070 * Code generator: details of internal data cache have no impact on the
  1071 user space functionality any longer.
  1072 
  1073 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1074 subgoals.  This is more appropriate for interpretations with 'where'.
  1075 INCOMPATIBILITY.
  1076 
  1077 * Command 'example_proof' opens an empty proof body.  This allows to
  1078 experiment with Isar, without producing any persistent result.
  1079 
  1080 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1081 within a local theory context, with explicit checking of the
  1082 constructors involved (in contrast to the raw 'syntax' versions).
  1083 
  1084 * Commands 'types' and 'typedecl' now work within a local theory
  1085 context -- without introducing dependencies on parameters or
  1086 assumptions, which is not possible in Isabelle/Pure.
  1087 
  1088 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1089 within a local theory context.  Minor INCOMPATIBILITY.
  1090 
  1091 
  1092 *** HOL ***
  1093 
  1094 * Command 'typedef' now works within a local theory context -- without
  1095 introducing dependencies on parameters or assumptions, which is not
  1096 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1097 contain multiple interpretations of local typedefs (with different
  1098 non-emptiness proofs), even in a global theory context.
  1099 
  1100 * New package for quotient types.  Commands 'quotient_type' and
  1101 'quotient_definition' may be used for defining types and constants by
  1102 quotient constructions.  An example is the type of integers created by
  1103 quotienting pairs of natural numbers:
  1104 
  1105   fun
  1106     intrel :: "(nat * nat) => (nat * nat) => bool"
  1107   where
  1108     "intrel (x, y) (u, v) = (x + v = u + y)"
  1109 
  1110   quotient_type int = "nat * nat" / intrel
  1111     by (auto simp add: equivp_def expand_fun_eq)
  1112 
  1113   quotient_definition
  1114     "0::int" is "(0::nat, 0::nat)"
  1115 
  1116 The method "lifting" can be used to lift of theorems from the
  1117 underlying "raw" type to the quotient type.  The example
  1118 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1119 construction and provides a reasoning infrastructure for finite sets.
  1120 
  1121 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1122 clash with new theory Quotient in Main HOL.
  1123 
  1124 * Moved the SMT binding into the main HOL session, eliminating
  1125 separate HOL-SMT session.
  1126 
  1127 * List membership infix mem operation is only an input abbreviation.
  1128 INCOMPATIBILITY.
  1129 
  1130 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1131 for future developements; former Library/Word.thy is still present in
  1132 the AFP entry RSAPPS.
  1133 
  1134 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1135 longer shadowed.  INCOMPATIBILITY.
  1136 
  1137 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1138 INCOMPATIBILITY.
  1139 
  1140 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1141 INCOMPATIBILITY.
  1142 
  1143 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1144 instead.  INCOMPATIBILITY.
  1145 
  1146 * Dropped several real-specific versions of lemmas about floor and
  1147 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1148 instead.  INCOMPATIBILITY.
  1149 
  1150   floor_number_of_eq         ~> floor_number_of
  1151   le_floor_eq_number_of      ~> number_of_le_floor
  1152   le_floor_eq_zero           ~> zero_le_floor
  1153   le_floor_eq_one            ~> one_le_floor
  1154   floor_less_eq_number_of    ~> floor_less_number_of
  1155   floor_less_eq_zero         ~> floor_less_zero
  1156   floor_less_eq_one          ~> floor_less_one
  1157   less_floor_eq_number_of    ~> number_of_less_floor
  1158   less_floor_eq_zero         ~> zero_less_floor
  1159   less_floor_eq_one          ~> one_less_floor
  1160   floor_le_eq_number_of      ~> floor_le_number_of
  1161   floor_le_eq_zero           ~> floor_le_zero
  1162   floor_le_eq_one            ~> floor_le_one
  1163   floor_subtract_number_of   ~> floor_diff_number_of
  1164   floor_subtract_one         ~> floor_diff_one
  1165   ceiling_number_of_eq       ~> ceiling_number_of
  1166   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1167   ceiling_le_zero_eq         ~> ceiling_le_zero
  1168   ceiling_le_eq_one          ~> ceiling_le_one
  1169   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1170   less_ceiling_eq_zero       ~> zero_less_ceiling
  1171   less_ceiling_eq_one        ~> one_less_ceiling
  1172   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1173   ceiling_less_eq_zero       ~> ceiling_less_zero
  1174   ceiling_less_eq_one        ~> ceiling_less_one
  1175   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1176   le_ceiling_eq_zero         ~> zero_le_ceiling
  1177   le_ceiling_eq_one          ~> one_le_ceiling
  1178   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1179   ceiling_subtract_one       ~> ceiling_diff_one
  1180 
  1181 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1182 application of the various fold combinators on finite sets.
  1183 
  1184 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1185 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1186 implementation.  INCOMPATIBILTY.
  1187 
  1188 * Theory Library/Coinductive_List has been removed -- superseded by
  1189 AFP/thys/Coinductive.
  1190 
  1191 * Theory PReal, including the type "preal" and related operations, has
  1192 been removed.  INCOMPATIBILITY.
  1193 
  1194 * Real: new development using Cauchy Sequences.
  1195 
  1196 * Split off theory "Big_Operators" containing setsum, setprod,
  1197 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1198 
  1199 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1200 "Int" etc.  INCOMPATIBILITY.
  1201 
  1202 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1203 
  1204 * New set of rules "ac_simps" provides combined assoc / commute
  1205 rewrites for all interpretations of the appropriate generic locales.
  1206 
  1207 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1208 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1209 appropriate and more consistent names suitable for name prefixes
  1210 within the HOL theories.  INCOMPATIBILITY.
  1211 
  1212 * Some generic constants have been put to appropriate theories:
  1213   - less_eq, less: Orderings
  1214   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1215   - inverse, divide: Rings
  1216 INCOMPATIBILITY.
  1217 
  1218 * More consistent naming of type classes involving orderings (and
  1219 lattices):
  1220 
  1221     lower_semilattice                   ~> semilattice_inf
  1222     upper_semilattice                   ~> semilattice_sup
  1223 
  1224     dense_linear_order                  ~> dense_linorder
  1225 
  1226     pordered_ab_group_add               ~> ordered_ab_group_add
  1227     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1228     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1229     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1230     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1231     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1232     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1233     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1234     pordered_comm_ring                  ~> ordered_comm_ring
  1235     pordered_comm_semiring              ~> ordered_comm_semiring
  1236     pordered_ring                       ~> ordered_ring
  1237     pordered_ring_abs                   ~> ordered_ring_abs
  1238     pordered_semiring                   ~> ordered_semiring
  1239 
  1240     ordered_ab_group_add                ~> linordered_ab_group_add
  1241     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1242     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1243     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1244     ordered_field                       ~> linordered_field
  1245     ordered_field_no_lb                 ~> linordered_field_no_lb
  1246     ordered_field_no_ub                 ~> linordered_field_no_ub
  1247     ordered_field_dense_linear_order    ~> dense_linordered_field
  1248     ordered_idom                        ~> linordered_idom
  1249     ordered_ring                        ~> linordered_ring
  1250     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1251     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1252     ordered_ring_strict                 ~> linordered_ring_strict
  1253     ordered_semidom                     ~> linordered_semidom
  1254     ordered_semiring                    ~> linordered_semiring
  1255     ordered_semiring_1                  ~> linordered_semiring_1
  1256     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1257     ordered_semiring_strict             ~> linordered_semiring_strict
  1258 
  1259   The following slightly odd type classes have been moved to a
  1260   separate theory Library/Lattice_Algebras:
  1261 
  1262     lordered_ab_group_add               ~> lattice_ab_group_add
  1263     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1264     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1265     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1266     lordered_ring                       ~> lattice_ring
  1267 
  1268 INCOMPATIBILITY.
  1269 
  1270 * Refined field classes:
  1271   - classes division_ring_inverse_zero, field_inverse_zero,
  1272     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1273     subsumes former division_by_zero class;
  1274   - numerous lemmas have been ported from field to division_ring.
  1275 INCOMPATIBILITY.
  1276 
  1277 * Refined algebra theorem collections:
  1278   - dropped theorem group group_simps, use algebra_simps instead;
  1279   - dropped theorem group ring_simps, use field_simps instead;
  1280   - proper theorem collection field_simps subsumes former theorem
  1281     groups field_eq_simps and field_simps;
  1282   - dropped lemma eq_minus_self_iff which is a duplicate for
  1283     equal_neg_zero.
  1284 INCOMPATIBILITY.
  1285 
  1286 * Theory Finite_Set and List: some lemmas have been generalized from
  1287 sets to lattices:
  1288 
  1289   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1290   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1291   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1292   union_Union_fold_union        ~> sup_Sup_fold_sup
  1293   Inter_fold_inter              ~> Inf_fold_inf
  1294   Union_fold_union              ~> Sup_fold_sup
  1295   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1296   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1297   INTER_fold_inter              ~> INFI_fold_inf
  1298   UNION_fold_union              ~> SUPR_fold_sup
  1299 
  1300 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1301 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1302 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1303 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1304 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1305 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1306 
  1307 * Reorganized theory Multiset: swapped notation of pointwise and
  1308 multiset order:
  1309 
  1310   - pointwise ordering is instance of class order with standard syntax
  1311     <= and <;
  1312   - multiset ordering has syntax <=# and <#; partial order properties
  1313     are provided by means of interpretation with prefix
  1314     multiset_order;
  1315   - less duplication, less historical organization of sections,
  1316     conversion from associations lists to multisets, rudimentary code
  1317     generation;
  1318   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1319     if needed.
  1320 
  1321 Renamed:
  1322 
  1323   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1324   multi_count_ext  ~>  multiset_ext
  1325   diff_union_inverse2  ~>  diff_union_cancelR
  1326 
  1327 INCOMPATIBILITY.
  1328 
  1329 * Theory Permutation: replaced local "remove" by List.remove1.
  1330 
  1331 * Code generation: ML and OCaml code is decorated with signatures.
  1332 
  1333 * Theory List: added transpose.
  1334 
  1335 * Library/Nat_Bijection.thy is a collection of bijective functions
  1336 between nat and other types, which supersedes the older libraries
  1337 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1338 
  1339   Constants:
  1340   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1341   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1342   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1343   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1344   Countable.pair_encode           ~> prod_encode
  1345   NatIso.prod2nat                 ~> prod_encode
  1346   NatIso.nat2prod                 ~> prod_decode
  1347   NatIso.sum2nat                  ~> sum_encode
  1348   NatIso.nat2sum                  ~> sum_decode
  1349   NatIso.list2nat                 ~> list_encode
  1350   NatIso.nat2list                 ~> list_decode
  1351   NatIso.set2nat                  ~> set_encode
  1352   NatIso.nat2set                  ~> set_decode
  1353 
  1354   Lemmas:
  1355   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1356   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1357   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1358   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1359   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1360   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1361   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1362   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1363   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1364   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1365   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1366   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1367   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1368 
  1369 * Sledgehammer:
  1370   - Renamed ATP commands:
  1371     atp_info     ~> sledgehammer running_atps
  1372     atp_kill     ~> sledgehammer kill_atps
  1373     atp_messages ~> sledgehammer messages
  1374     atp_minimize ~> sledgehammer minimize
  1375     print_atps   ~> sledgehammer available_atps
  1376     INCOMPATIBILITY.
  1377   - Added user's manual ("isabelle doc sledgehammer").
  1378   - Added option syntax and "sledgehammer_params" to customize
  1379     Sledgehammer's behavior.  See the manual for details.
  1380   - Modified the Isar proof reconstruction code so that it produces
  1381     direct proofs rather than proofs by contradiction.  (This feature
  1382     is still experimental.)
  1383   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1384     full-typed mode.
  1385   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1386 
  1387 * Nitpick:
  1388   - Added and implemented "binary_ints" and "bits" options.
  1389   - Added "std" option and implemented support for nonstandard models.
  1390   - Added and implemented "finitize" option to improve the precision
  1391     of infinite datatypes based on a monotonicity analysis.
  1392   - Added support for quotient types.
  1393   - Added support for "specification" and "ax_specification"
  1394     constructs.
  1395   - Added support for local definitions (for "function" and
  1396     "termination" proofs).
  1397   - Added support for term postprocessors.
  1398   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1399   - Improved efficiency of "destroy_constrs" optimization.
  1400   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1401     record getters.
  1402   - Fixed soundness bug related to higher-order constructors.
  1403   - Fixed soundness bug when "full_descrs" is enabled.
  1404   - Improved precision of set constructs.
  1405   - Added "atoms" option.
  1406   - Added cache to speed up repeated Kodkod invocations on the same
  1407     problems.
  1408   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1409     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1410     "SAT4J_Light".  INCOMPATIBILITY.
  1411   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1412     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1413   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1414 
  1415 * Method "induct" now takes instantiations of the form t, where t is not
  1416   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1417   If this is not intended, t has to be enclosed in parentheses.
  1418   By default, the equalities generated by definitional instantiations
  1419   are pre-simplified, which may cause parameters of inductive cases
  1420   to disappear, or may even delete some of the inductive cases.
  1421   Use "induct (no_simp)" instead of "induct" to restore the old
  1422   behaviour. The (no_simp) option is also understood by the "cases"
  1423   and "nominal_induct" methods, which now perform pre-simplification, too.
  1424   INCOMPATIBILITY.
  1425 
  1426 
  1427 *** HOLCF ***
  1428 
  1429 * Variable names in lemmas generated by the domain package have
  1430 changed; the naming scheme is now consistent with the HOL datatype
  1431 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1432 
  1433 * The domain package no longer defines the function "foo_copy" for
  1434 recursive domain "foo".  The reach lemma is now stated directly in
  1435 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1436 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1437 
  1438 * Most definedness lemmas generated by the domain package (previously
  1439 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1440 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1441 Proofs that used definedness lemmas as intro rules may break,
  1442 potential INCOMPATIBILITY.
  1443 
  1444 * Induction and casedist rules generated by the domain package now
  1445 declare proper case_names (one called "bottom", and one named for each
  1446 constructor).  INCOMPATIBILITY.
  1447 
  1448 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1449 rules are generated for each domain, INCOMPATIBILITY.
  1450 
  1451   foo_bar.reach       ~> foo.reach  bar.reach
  1452   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1453 
  1454 * Some lemmas generated by the domain package have been renamed for
  1455 consistency with the datatype package, INCOMPATIBILITY.
  1456 
  1457   foo.ind        ~> foo.induct
  1458   foo.finite_ind ~> foo.finite_induct
  1459   foo.coind      ~> foo.coinduct
  1460   foo.casedist   ~> foo.exhaust
  1461   foo.exhaust    ~> foo.nchotomy
  1462 
  1463 * For consistency with other definition packages, the fixrec package
  1464 now generates qualified theorem names, INCOMPATIBILITY.
  1465 
  1466   foo_simps  ~> foo.simps
  1467   foo_unfold ~> foo.unfold
  1468   foo_induct ~> foo.induct
  1469 
  1470 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1471 method and internal fixrec proofs now use the default simpset instead.
  1472 INCOMPATIBILITY.
  1473 
  1474 * The "contlub" predicate has been removed.  Proof scripts should use
  1475 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1476 
  1477 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1478 
  1479 * The constants cpair, cfst, and csnd have been removed in favor of
  1480 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1481 
  1482 
  1483 *** ML ***
  1484 
  1485 * Antiquotations for basic formal entities:
  1486 
  1487     @{class NAME}         -- type class
  1488     @{class_syntax NAME}  -- syntax representation of the above
  1489 
  1490     @{type_name NAME}     -- logical type
  1491     @{type_abbrev NAME}   -- type abbreviation
  1492     @{nonterminal NAME}   -- type of concrete syntactic category
  1493     @{type_syntax NAME}   -- syntax representation of any of the above
  1494 
  1495     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1496     @{const_abbrev NAME}  -- abbreviated constant
  1497     @{const_syntax NAME}  -- syntax representation of any of the above
  1498 
  1499 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1500 syntax constant (cf. 'syntax' command).
  1501 
  1502 * Antiquotation @{make_string} inlines a function to print arbitrary
  1503 values similar to the ML toplevel.  The result is compiler dependent
  1504 and may fall back on "?" in certain situations.
  1505 
  1506 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1507 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1508 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1509 not work with the asynchronous Isar document model.
  1510 
  1511 * Configuration options now admit dynamic default values, depending on
  1512 the context or even global references.
  1513 
  1514 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1515 uses an efficient external library if available (for Poly/ML).
  1516 
  1517 * Renamed some important ML structures, while keeping the old names
  1518 for some time as aliases within the structure Legacy:
  1519 
  1520   OuterKeyword  ~>  Keyword
  1521   OuterLex      ~>  Token
  1522   OuterParse    ~>  Parse
  1523   OuterSyntax   ~>  Outer_Syntax
  1524   PrintMode     ~>  Print_Mode
  1525   SpecParse     ~>  Parse_Spec
  1526   ThyInfo       ~>  Thy_Info
  1527   ThyLoad       ~>  Thy_Load
  1528   ThyOutput     ~>  Thy_Output
  1529   TypeInfer     ~>  Type_Infer
  1530 
  1531 Note that "open Legacy" simplifies porting of sources, but forgetting
  1532 to remove it again will complicate porting again in the future.
  1533 
  1534 * Most operations that refer to a global context are named
  1535 accordingly, e.g. Simplifier.global_context or
  1536 ProofContext.init_global.  There are some situations where a global
  1537 context actually works, but under normal circumstances one needs to
  1538 pass the proper local context through the code!
  1539 
  1540 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1541 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1542 Pretty.pp argument to merge, which is absent in the standard
  1543 Theory_Data version.
  1544 
  1545 * Sorts.certify_sort and derived "cert" operations for types and terms
  1546 no longer minimize sorts.  Thus certification at the boundary of the
  1547 inference kernel becomes invariant under addition of class relations,
  1548 which is an important monotonicity principle.  Sorts are now minimized
  1549 in the syntax layer only, at the boundary between the end-user and the
  1550 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1551 explicitly in rare situations.
  1552 
  1553 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1554 emphasize that this is in no way a standard operation.
  1555 INCOMPATIBILITY.
  1556 
  1557 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1558 usual for resolution.  Rare INCOMPATIBILITY.
  1559 
  1560 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1561 to emphasize that these only work in a global situation (which is
  1562 quite rare).
  1563 
  1564 * Curried take and drop in library.ML; negative length is interpreted
  1565 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1566 
  1567 * Proof terms: type substitutions on proof constants now use canonical
  1568 order of type variables.  INCOMPATIBILITY for tools working with proof
  1569 terms.
  1570 
  1571 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1572 may no longer carry premises.  User-level specifications are
  1573 transformed accordingly by Thm.add_axiom/add_def.
  1574 
  1575 
  1576 *** System ***
  1577 
  1578 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1579 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1580 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1581 
  1582 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1583 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1584 respectively.
  1585 
  1586 * Old lib/scripts/polyml-platform is superseded by the
  1587 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1588 variant, even on a 64 bit machine.  The following example setting
  1589 prefers 64 bit if available:
  1590 
  1591   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1592 
  1593 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1594 Isabelle/Scala layer for advanced prover interaction and integration.
  1595 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1596 component.
  1597 
  1598 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1599 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1600 similar to the default assignment of the document preparation system
  1601 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1602 provides some operations for direct access to the font without asking
  1603 the user for manual installation.
  1604 
  1605 
  1606 
  1607 New in Isabelle2009-1 (December 2009)
  1608 -------------------------------------
  1609 
  1610 *** General ***
  1611 
  1612 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1613 one backslash should be used, even in ML sources.
  1614 
  1615 
  1616 *** Pure ***
  1617 
  1618 * Locale interpretation propagates mixins along the locale hierarchy.
  1619 The currently only available mixins are the equations used to map
  1620 local definitions to terms of the target domain of an interpretation.
  1621 
  1622 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1623 loc" to print all interpretations of locale "loc" in the theory.
  1624 Interpretations in proofs are not shown.
  1625 
  1626 * Thoroughly revised locales tutorial.  New section on conditional
  1627 interpretation.
  1628 
  1629 * On instantiation of classes, remaining undefined class parameters
  1630 are formally declared.  INCOMPATIBILITY.
  1631 
  1632 
  1633 *** Document preparation ***
  1634 
  1635 * New generalized style concept for printing terms: @{foo (style) ...}
  1636 instead of @{foo_style style ...}  (old form is still retained for
  1637 backward compatibility).  Styles can be also applied for
  1638 antiquotations prop, term_type and typeof.
  1639 
  1640 
  1641 *** HOL ***
  1642 
  1643 * New proof method "smt" for a combination of first-order logic with
  1644 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1645 fixed-size bitvectors; there is also basic support for higher-order
  1646 features (esp. lambda abstractions).  It is an incomplete decision
  1647 procedure based on external SMT solvers using the oracle mechanism;
  1648 for the SMT solver Z3, this method is proof-producing.  Certificates
  1649 are provided to avoid calling the external solvers solely for
  1650 re-checking proofs.  Due to a remote SMT service there is no need for
  1651 installing SMT solvers locally.  See src/HOL/SMT.
  1652 
  1653 * New commands to load and prove verification conditions generated by
  1654 the Boogie program verifier or derived systems (e.g. the Verifying C
  1655 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1656 
  1657 * New counterexample generator tool 'nitpick' based on the Kodkod
  1658 relational model finder.  See src/HOL/Tools/Nitpick and
  1659 src/HOL/Nitpick_Examples.
  1660 
  1661 * New commands 'code_pred' and 'values' to invoke the predicate
  1662 compiler and to enumerate values of inductive predicates.
  1663 
  1664 * A tabled implementation of the reflexive transitive closure.
  1665 
  1666 * New implementation of quickcheck uses generic code generator;
  1667 default generators are provided for all suitable HOL types, records
  1668 and datatypes.  Old quickcheck can be re-activated importing theory
  1669 Library/SML_Quickcheck.
  1670 
  1671 * New testing tool Mirabelle for automated proof tools.  Applies
  1672 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1673 every proof step in a theory.  To be used in batch mode via the
  1674 "mirabelle" utility.
  1675 
  1676 * New proof method "sos" (sum of squares) for nonlinear real
  1677 arithmetic (originally due to John Harison). It requires theory
  1678 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1679 works well in practice on quantifier-free real arithmetic with +, -,
  1680 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1681 inequalities between polynomials.  It makes use of external
  1682 semidefinite programming solvers.  Method "sos" generates a
  1683 certificate that can be pasted into the proof thus avoiding the need
  1684 to call an external tool every time the proof is checked.  See
  1685 src/HOL/Library/Sum_Of_Squares.
  1686 
  1687 * New method "linarith" invokes existing linear arithmetic decision
  1688 procedure only.
  1689 
  1690 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1691 
  1692 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1693 Causes full type information to be output to the ATPs.  This slows
  1694 ATPs down considerably but eliminates a source of unsound "proofs"
  1695 that fail later.
  1696 
  1697 * New method "metisFT": A version of metis that uses full type
  1698 information in order to avoid failures of proof reconstruction.
  1699 
  1700 * New evaluator "approximate" approximates an real valued term using
  1701 the same method as the approximation method.
  1702 
  1703 * Method "approximate" now supports arithmetic expressions as
  1704 boundaries of intervals and implements interval splitting and Taylor
  1705 series expansion.
  1706 
  1707 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1708 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1709 
  1710 * New theory SupInf of the supremum and infimum operators for sets of
  1711 reals.
  1712 
  1713 * New theory Probability, which contains a development of measure
  1714 theory, eventually leading to Lebesgue integration and probability.
  1715 
  1716 * Extended Multivariate Analysis to include derivation and Brouwer's
  1717 fixpoint theorem.
  1718 
  1719 * Reorganization of number theory, INCOMPATIBILITY:
  1720   - new number theory development for nat and int, in theories Divides
  1721     and GCD as well as in new session Number_Theory
  1722   - some constants and facts now suffixed with _nat and _int
  1723     accordingly
  1724   - former session NumberTheory now named Old_Number_Theory, including
  1725     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1726   - moved theory Pocklington from src/HOL/Library to
  1727     src/HOL/Old_Number_Theory
  1728 
  1729 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1730 lcm of finite and infinite sets. It is shown that they form a complete
  1731 lattice.
  1732 
  1733 * Class semiring_div requires superclass no_zero_divisors and proof of
  1734 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1735 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1736 generalized to class semiring_div, subsuming former theorems
  1737 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1738 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1739 INCOMPATIBILITY.
  1740 
  1741 * Refinements to lattice classes and sets:
  1742   - less default intro/elim rules in locale variant, more default
  1743     intro/elim rules in class variant: more uniformity
  1744   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1745     le_inf_iff
  1746   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1747     sup_aci)
  1748   - renamed ACI to inf_sup_aci
  1749   - new class "boolean_algebra"
  1750   - class "complete_lattice" moved to separate theory
  1751     "Complete_Lattice"; corresponding constants (and abbreviations)
  1752     renamed and with authentic syntax:
  1753     Set.Inf ~>    Complete_Lattice.Inf
  1754     Set.Sup ~>    Complete_Lattice.Sup
  1755     Set.INFI ~>   Complete_Lattice.INFI
  1756     Set.SUPR ~>   Complete_Lattice.SUPR
  1757     Set.Inter ~>  Complete_Lattice.Inter
  1758     Set.Union ~>  Complete_Lattice.Union
  1759     Set.INTER ~>  Complete_Lattice.INTER
  1760     Set.UNION ~>  Complete_Lattice.UNION
  1761   - authentic syntax for
  1762     Set.Pow
  1763     Set.image
  1764   - mere abbreviations:
  1765     Set.empty               (for bot)
  1766     Set.UNIV                (for top)
  1767     Set.inter               (for inf, formerly Set.Int)
  1768     Set.union               (for sup, formerly Set.Un)
  1769     Complete_Lattice.Inter  (for Inf)
  1770     Complete_Lattice.Union  (for Sup)
  1771     Complete_Lattice.INTER  (for INFI)
  1772     Complete_Lattice.UNION  (for SUPR)
  1773   - object-logic definitions as far as appropriate
  1774 
  1775 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1776 Un_subset_iff are explicitly deleted as default simp rules; then also
  1777 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1778 deleted to achieve the desired effect.
  1779 
  1780 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1781 rules by default any longer; the same applies to min_max.inf_absorb1
  1782 etc.  INCOMPATIBILITY.
  1783 
  1784 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1785 pred_set_conv by default.  INCOMPATIBILITY.
  1786 
  1787 * Power operations on relations and functions are now one dedicated
  1788 constant "compow" with infix syntax "^^".  Power operation on
  1789 multiplicative monoids retains syntax "^" and is now defined generic
  1790 in class power.  INCOMPATIBILITY.
  1791 
  1792 * Relation composition "R O S" now has a more standard argument order:
  1793 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1794 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1795 break, since the O_assoc rule was not rewritten like this.  Fix using
  1796 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1797 
  1798 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1799 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1800 INCOMPATIBILITY.
  1801 
  1802 * Most rules produced by inductive and datatype package have mandatory
  1803 prefixes.  INCOMPATIBILITY.
  1804 
  1805 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1806 the attribute of the same name.  Each of the theorems in the list
  1807 DERIV_intros assumes composition with an additional function and
  1808 matches a variable to the derivative, which has to be solved by the
  1809 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1810 of most elementary terms.  Former Maclauren.DERIV_tac and
  1811 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1812 INCOMPATIBILITY.
  1813 
  1814 * Code generator attributes follow the usual underscore convention:
  1815     code_unfold     replaces    code unfold
  1816     code_post       replaces    code post
  1817     etc.
  1818   INCOMPATIBILITY.
  1819 
  1820 * Renamed methods:
  1821     sizechange -> size_change
  1822     induct_scheme -> induction_schema
  1823   INCOMPATIBILITY.
  1824 
  1825 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1826 INCOMPATIBILITY, use "undefined" directly.
  1827 
  1828 * Renamed theorems:
  1829     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1830     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1831     Suc_plus1 -> Suc_eq_plus1
  1832     *anti_sym -> *antisym*
  1833     vector_less_eq_def -> vector_le_def
  1834   INCOMPATIBILITY.
  1835 
  1836 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1837 INCOMPATIBILITY.
  1838 
  1839 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1840 INCOMPATIBILITY.
  1841 
  1842 
  1843 *** HOLCF ***
  1844 
  1845 * Theory Representable defines a class "rep" of domains that are
  1846 representable (via an ep-pair) in the universal domain type "udom".
  1847 Instances are provided for all type constructors defined in HOLCF.
  1848 
  1849 * The 'new_domain' command is a purely definitional version of the
  1850 domain package, for representable domains.  Syntax is identical to the
  1851 old domain package.  The 'new_domain' package also supports indirect
  1852 recursion using previously-defined type constructors.  See
  1853 src/HOLCF/ex/New_Domain.thy for examples.
  1854 
  1855 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1856 on the left-hand side of an equation, and then performs
  1857 simplification.  Rewriting is done using rules declared with the
  1858 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1859 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1860 
  1861 * The pattern-match compiler in 'fixrec' can now handle constructors
  1862 with HOL function types.  Pattern-match combinators for the Pair
  1863 constructor are pre-configured.
  1864 
  1865 * The 'fixrec' package now produces better fixed-point induction rules
  1866 for mutually-recursive definitions:  Induction rules have conclusions
  1867 of the form "P foo bar" instead of "P <foo, bar>".
  1868 
  1869 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1870 been renamed to "below".  The name "below" now replaces "less" in many
  1871 theorem names.  (Legacy theorem names using "less" are still supported
  1872 as well.)
  1873 
  1874 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1875 patterns can be used to generate strictness rules, or to make
  1876 functions more strict (much like the bang-patterns supported by the
  1877 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1878 examples.
  1879 
  1880 
  1881 *** ML ***
  1882 
  1883 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1884 errors and run-time exceptions, including detailed source positions.
  1885 
  1886 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1887 identified entries, with some additional information such as source
  1888 position, logical grouping etc.
  1889 
  1890 * Theory and context data is now introduced by the simplified and
  1891 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1892 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1893 copy operation) is still available for some time.
  1894 
  1895 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1896 provides a high-level programming interface to synchronized state
  1897 variables with atomic update.  This works via pure function
  1898 application within a critical section -- its runtime should be as
  1899 short as possible; beware of deadlocks if critical code is nested,
  1900 either directly or indirectly via other synchronized variables!
  1901 
  1902 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1903 wraps raw ML references, explicitly indicating their non-thread-safe
  1904 behaviour.  The Isar toplevel keeps this structure open, to
  1905 accommodate Proof General as well as quick and dirty interactive
  1906 experiments with references.
  1907 
  1908 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1909 parallel tactical reasoning.
  1910 
  1911 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1912 are similar to SUBPROOF, but are slightly more flexible: only the
  1913 specified parts of the subgoal are imported into the context, and the
  1914 body tactic may introduce new subgoals and schematic variables.
  1915 
  1916 * Old tactical METAHYPS, which does not observe the proof context, has
  1917 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1918 or Subgoal.FOCUS etc.
  1919 
  1920 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1921 functors have their own ML name space there is no point to mark them
  1922 separately.)  Minor INCOMPATIBILITY.
  1923 
  1924 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1925 
  1926 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1927 INCOMPATIBILITY.
  1928 
  1929 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1930 mode, which avoids critical setmp.
  1931 
  1932 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1933 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1934 Attrib/Method.setup introduced in Isabelle2009.
  1935 
  1936 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1937 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1938 last resort.  INCOMPATIBILITY.
  1939 
  1940 * Display.pretty_thm now requires a proper context (cf. former
  1941 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1942 or even Display.pretty_thm_without_context as last resort.
  1943 INCOMPATIBILITY.
  1944 
  1945 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1946 Syntax.pretty_typ/term directly, preferably with proper context
  1947 instead of global theory.
  1948 
  1949 
  1950 *** System ***
  1951 
  1952 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1953 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1954 usedir option -q.
  1955 
  1956 * Support for additional "Isabelle components" via etc/components, see
  1957 also the system manual.
  1958 
  1959 * The isabelle makeall tool now operates on all components with
  1960 IsaMakefile, not just hardwired "logics".
  1961 
  1962 * Removed "compress" option from isabelle-process and isabelle usedir;
  1963 this is always enabled.
  1964 
  1965 * Discontinued support for Poly/ML 4.x versions.
  1966 
  1967 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  1968 on a given logic image.  This requires the lighttpd webserver and is
  1969 currently supported on Linux only.
  1970 
  1971 
  1972 
  1973 New in Isabelle2009 (April 2009)
  1974 --------------------------------
  1975 
  1976 *** General ***
  1977 
  1978 * Simplified main Isabelle executables, with less surprises on
  1979 case-insensitive file-systems (such as Mac OS).
  1980 
  1981   - The main Isabelle tool wrapper is now called "isabelle" instead of
  1982     "isatool."
  1983 
  1984   - The former "isabelle" alias for "isabelle-process" has been
  1985     removed (should rarely occur to regular users).
  1986 
  1987   - The former "isabelle-interface" and its alias "Isabelle" have been
  1988     removed (interfaces are now regular Isabelle tools).
  1989 
  1990 Within scripts and make files, the Isabelle environment variables
  1991 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  1992 respectively.  (The latter are still available as legacy feature.)
  1993 
  1994 The old isabelle-interface wrapper could react in confusing ways if
  1995 the interface was uninstalled or changed otherwise.  Individual
  1996 interface tool configuration is now more explicit, see also the
  1997 Isabelle system manual.  In particular, Proof General is now available
  1998 via "isabelle emacs".
  1999 
  2000 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  2001 purge installed copies of Isabelle executables and re-run "isabelle
  2002 install -p ...", or use symlinks.
  2003 
  2004 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  2005 old ~/isabelle, which was slightly non-standard and apt to cause
  2006 surprises on case-insensitive file-systems (such as Mac OS).
  2007 
  2008 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  2009 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  2010 care is required when using older releases of Isabelle.  Note that
  2011 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  2012 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  2013 
  2014 * Proofs of fully specified statements are run in parallel on
  2015 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  2016 a regular 4-core machine, if the initial heap space is made reasonably
  2017 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  2018 
  2019 * The main reference manuals ("isar-ref", "implementation", and
  2020 "system") have been updated and extended.  Formally checked references
  2021 as hyperlinks are now available uniformly.
  2022 
  2023 
  2024 *** Pure ***
  2025 
  2026 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  2027 respects.  The most important changes are listed below.  See the
  2028 Tutorial on Locales ("locales" manual) for details.
  2029 
  2030 - In locale expressions, instantiation replaces renaming.  Parameters
  2031 must be declared in a for clause.  To aid compatibility with previous
  2032 parameter inheritance, in locale declarations, parameters that are not
  2033 'touched' (instantiation position "_" or omitted) are implicitly added
  2034 with their syntax at the beginning of the for clause.
  2035 
  2036 - Syntax from abbreviations and definitions in locales is available in
  2037 locale expressions and context elements.  The latter is particularly
  2038 useful in locale declarations.
  2039 
  2040 - More flexible mechanisms to qualify names generated by locale
  2041 expressions.  Qualifiers (prefixes) may be specified in locale
  2042 expressions, and can be marked as mandatory (syntax: "name!:") or
  2043 optional (syntax "name?:").  The default depends for plain "name:"
  2044 depends on the situation where a locale expression is used: in
  2045 commands 'locale' and 'sublocale' prefixes are optional, in
  2046 'interpretation' and 'interpret' prefixes are mandatory.  The old
  2047 implicit qualifiers derived from the parameter names of a locale are
  2048 no longer generated.
  2049 
  2050 - Command "sublocale l < e" replaces "interpretation l < e".  The
  2051 instantiation clause in "interpretation" and "interpret" (square
  2052 brackets) is no longer available.  Use locale expressions.
  2053 
  2054 - When converting proof scripts, mandatory qualifiers in
  2055 'interpretation' and 'interpret' should be retained by default, even
  2056 if this is an INCOMPATIBILITY compared to former behavior.  In the
  2057 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  2058 in locale expressions range over a single locale instance only.
  2059 
  2060 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  2061 In existing theorem specifications replace the includes element by the
  2062 respective context elements of the included locale, omitting those
  2063 that are already present in the theorem specification.  Multiple
  2064 assume elements of a locale should be replaced by a single one
  2065 involving the locale predicate.  In the proof body, declarations (most
  2066 notably theorems) may be regained by interpreting the respective
  2067 locales in the proof context as required (command "interpret").
  2068 
  2069 If using "includes" in replacement of a target solely because the
  2070 parameter types in the theorem are not as general as in the target,
  2071 consider declaring a new locale with additional type constraints on
  2072 the parameters (context element "constrains").
  2073 
  2074 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2075 
  2076 - Locale interpretation commands no longer attempt to simplify goal.
  2077 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2078 methods intro_locales and unfold_locales to clarify.
  2079 
  2080 - Locale interpretation commands no longer accept interpretation
  2081 attributes.  INCOMPATIBILITY.
  2082 
  2083 * Class declaration: so-called "base sort" must not be given in import
  2084 list any longer, but is inferred from the specification.  Particularly
  2085 in HOL, write
  2086 
  2087     class foo = ...
  2088 
  2089 instead of
  2090 
  2091     class foo = type + ...
  2092 
  2093 * Class target: global versions of theorems stemming do not carry a
  2094 parameter prefix any longer.  INCOMPATIBILITY.
  2095 
  2096 * Class 'instance' command no longer accepts attached definitions.
  2097 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2098 
  2099 * Recovered hiding of consts, which was accidentally broken in
  2100 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2101 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2102 
  2103 * Slightly more coherent Pure syntax, with updated documentation in
  2104 isar-ref manual.  Removed locales meta_term_syntax and
  2105 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2106 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2107 directly in regular applications.
  2108 
  2109 * There is a new syntactic category "float_const" for signed decimal
  2110 fractions (e.g. 123.45 or -123.45).
  2111 
  2112 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2113 interface with 'setup' command instead.
  2114 
  2115 * Command 'local_setup' is similar to 'setup', but operates on a local
  2116 theory context.
  2117 
  2118 * The 'axiomatization' command now only works within a global theory
  2119 context.  INCOMPATIBILITY.
  2120 
  2121 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2122 hypotheses.  Sorts required in the course of reasoning need to be
  2123 covered by the constraints in the initial statement, completed by the
  2124 type instance information of the background theory.  Non-trivial sort
  2125 hypotheses, which rarely occur in practice, may be specified via
  2126 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2127 
  2128   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2129 
  2130 The result contains an implicit sort hypotheses as before --
  2131 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2132 normalization.
  2133 
  2134 * Generalized Isar history, with support for linear undo, direct state
  2135 addressing etc.
  2136 
  2137 * Changed defaults for unify configuration options:
  2138 
  2139   unify_trace_bound = 50 (formerly 25)
  2140   unify_search_bound = 60 (formerly 30)
  2141 
  2142 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2143 
  2144   a) On theory merge, the last set of code equations for a particular
  2145      constant is taken (in accordance with the policy applied by other
  2146      parts of the code generator framework).
  2147 
  2148   b) Code equations stemming from explicit declarations (e.g. code
  2149      attribute) gain priority over default code equations stemming
  2150      from definition, primrec, fun etc.
  2151 
  2152 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2153 
  2154 * Unified theorem tables for both code generators.  Thus [code
  2155 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2156 
  2157 * Command 'find_consts' searches for constants based on type and name
  2158 patterns, e.g.
  2159 
  2160     find_consts "_ => bool"
  2161 
  2162 By default, matching is against subtypes, but it may be restricted to
  2163 the whole type.  Searching by name is possible.  Multiple queries are
  2164 conjunctive and queries may be negated by prefixing them with a
  2165 hyphen:
  2166 
  2167     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2168 
  2169 * New 'find_theorems' criterion "solves" matches theorems that
  2170 directly solve the current goal (modulo higher-order unification).
  2171 
  2172 * Auto solve feature for main theorem statements: whenever a new goal
  2173 is stated, "find_theorems solves" is called; any theorems that could
  2174 solve the lemma directly are listed as part of the goal state.
  2175 Cf. associated options in Proof General Isabelle settings menu,
  2176 enabled by default, with reasonable timeout for pathological cases of
  2177 higher-order unification.
  2178 
  2179 
  2180 *** Document preparation ***
  2181 
  2182 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2183 demanding keyword 'by' and supporting the full method expression
  2184 syntax just like the Isar command 'by'.
  2185 
  2186 
  2187 *** HOL ***
  2188 
  2189 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2190 points Main and Complex_Main remain as before.
  2191 
  2192 * Logic image HOL-Plain provides a minimal HOL with the most important
  2193 tools available (inductive, datatype, primrec, ...).  This facilitates
  2194 experimentation and tool development.  Note that user applications
  2195 (and library theories) should never refer to anything below theory
  2196 Main, as before.
  2197 
  2198 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2199 experimentation due to shorter build times.
  2200 
  2201 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2202 were previously part of former HOL-Complex.  Entry point Hyperreal
  2203 remains valid, but theories formerly using Complex_Main should now use
  2204 new entry point Hypercomplex.
  2205 
  2206 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2207 Posix processes.  Avoids potentially expensive forking of the ML
  2208 process.  New thread-based implementation also works on non-Unix
  2209 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2210 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2211 commands are covered in the isar-ref manual.
  2212 
  2213 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2214 sledgehammer without local ATP installation (Vampire etc.). Other
  2215 provers may be included via suitable ML wrappers, see also
  2216 src/HOL/ATP_Linkup.thy.
  2217 
  2218 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2219 menu.
  2220 
  2221 * The metis method no longer fails because the theorem is too trivial
  2222 (contains the empty clause).
  2223 
  2224 * The metis method now fails in the usual manner, rather than raising
  2225 an exception, if it determines that it cannot prove the theorem.
  2226 
  2227 * Method "coherent" implements a prover for coherent logic (see also
  2228 src/Tools/coherent.ML).
  2229 
  2230 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2231 "undefined" is the right choice to replace "arbitrary", though
  2232 logically there is no difference.  INCOMPATIBILITY.
  2233 
  2234 * Command "value" now integrates different evaluation mechanisms.  The
  2235 result of the first successful evaluation mechanism is printed.  In
  2236 square brackets a particular named evaluation mechanisms may be
  2237 specified (currently, [SML], [code] or [nbe]).  See further
  2238 src/HOL/ex/Eval_Examples.thy.
  2239 
  2240 * Normalization by evaluation now allows non-leftlinear equations.
  2241 Declare with attribute [code nbe].
  2242 
  2243 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2244 as the structured Isar versions "cases" and "induct", cf. the
  2245 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2246 are now presented as a list of individual projections
  2247 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2248 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2249 rare situations a different rule is selected --- notably nested tuple
  2250 elimination instead of former prod.exhaust: use explicit (case_tac t
  2251 rule: prod.exhaust) here.
  2252 
  2253 * Attributes "cases", "induct", "coinduct" support "del" option.
  2254 
  2255 * Removed fact "case_split_thm", which duplicates "case_split".
  2256 
  2257 * The option datatype has been moved to a new theory Option.  Renamed
  2258 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2259 
  2260 * New predicate "strict_mono" classifies strict functions on partial
  2261 orders.  With strict functions on linear orders, reasoning about
  2262 (in)equalities is facilitated by theorems "strict_mono_eq",
  2263 "strict_mono_less_eq" and "strict_mono_less".
  2264 
  2265 * Some set operations are now proper qualified constants with
  2266 authentic syntax.  INCOMPATIBILITY:
  2267 
  2268     op Int ~>   Set.Int
  2269     op Un ~>    Set.Un
  2270     INTER ~>    Set.INTER
  2271     UNION ~>    Set.UNION
  2272     Inter ~>    Set.Inter
  2273     Union ~>    Set.Union
  2274     {} ~>       Set.empty
  2275     UNIV ~>     Set.UNIV
  2276 
  2277 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2278 theory Set.
  2279 
  2280 * Auxiliary class "itself" has disappeared -- classes without any
  2281 parameter are treated as expected by the 'class' command.
  2282 
  2283 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2284 
  2285 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2286 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2287 
  2288 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2289 method "approximation".  It proves formulas on real values by using
  2290 interval arithmetic.  In the formulas are also the transcendental
  2291 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2292 allowed. For examples see
  2293 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2294 
  2295 * Theory "Reflection" now resides in HOL/Library.
  2296 
  2297 * Entry point to Word library now simply named "Word".
  2298 INCOMPATIBILITY.
  2299 
  2300 * Made source layout more coherent with logical distribution
  2301 structure:
  2302 
  2303     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2304     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2305     src/HOL/Library/GCD.thy ~> src/HOL/
  2306     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2307     src/HOL/Library/Parity.thy ~> src/HOL/
  2308     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2309     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2310     src/HOL/Real/Lubs.thy ~> src/HOL/
  2311     src/HOL/Real/PReal.thy ~> src/HOL/
  2312     src/HOL/Real/Rational.thy ~> src/HOL/
  2313     src/HOL/Real/RComplete.thy ~> src/HOL/
  2314     src/HOL/Real/RealDef.thy ~> src/HOL/
  2315     src/HOL/Real/RealPow.thy ~> src/HOL/
  2316     src/HOL/Real/Real.thy ~> src/HOL/
  2317     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2318     src/HOL/Complex/Complex.thy ~> src/HOL/
  2319     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2320     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2321     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2322     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2323     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2324     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2325     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2326     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2327     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2328     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2329     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2330     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2331     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2332     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2333     src/HOL/Real/Float ~> src/HOL/Library/
  2334     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2335     src/HOL/Real/RealVector.thy ~> src/HOL/
  2336 
  2337     src/HOL/arith_data.ML ~> src/HOL/Tools
  2338     src/HOL/hologic.ML ~> src/HOL/Tools
  2339     src/HOL/simpdata.ML ~> src/HOL/Tools
  2340     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2341     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2342     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2343     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2344     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2345     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2346     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2347 
  2348     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2349     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2350     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2351     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2352     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2353     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2354 
  2355 * If methods "eval" and "evaluation" encounter a structured proof
  2356 state with !!/==>, only the conclusion is evaluated to True (if
  2357 possible), avoiding strange error messages.
  2358 
  2359 * Method "sizechange" automates termination proofs using (a
  2360 modification of) the size-change principle.  Requires SAT solver.  See
  2361 src/HOL/ex/Termination.thy for examples.
  2362 
  2363 * Simplifier: simproc for let expressions now unfolds if bound
  2364 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2365 
  2366 * Method "arith": Linear arithmetic now ignores all inequalities when
  2367 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2368 
  2369 * New attribute "arith" for facts that should always be used
  2370 automatically by arithmetic. It is intended to be used locally in
  2371 proofs, e.g.
  2372 
  2373   assumes [arith]: "x > 0"
  2374 
  2375 Global usage is discouraged because of possible performance impact.
  2376 
  2377 * New classes "top" and "bot" with corresponding operations "top" and
  2378 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2379 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2380 
  2381 * Changed definition lemma "less_fun_def" in order to provide an
  2382 instance for preorders on functions; use lemma "less_le" instead.
  2383 INCOMPATIBILITY.
  2384 
  2385 * Theory Orderings: class "wellorder" moved here, with explicit
  2386 induction rule "less_induct" as assumption.  For instantiation of
  2387 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2388 INCOMPATIBILITY.
  2389 
  2390 * Theory Orderings: added class "preorder" as superclass of "order".
  2391 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2392 etc. slightly changed.  Some theorems named order_class.* now named
  2393 preorder_class.*.
  2394 
  2395 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2396 "diag" to "Id_on".
  2397 
  2398 * Theory Finite_Set: added a new fold combinator of type
  2399 
  2400   ('a => 'b => 'b) => 'b => 'a set => 'b
  2401 
  2402 Occasionally this is more convenient than the old fold combinator
  2403 which is now defined in terms of the new one and renamed to
  2404 fold_image.
  2405 
  2406 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2407 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2408 extended with further lemmas!).  At the moment both still exist but
  2409 the former will disappear at some point.
  2410 
  2411 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2412 class recpower.  Type-specific simp rules for various recpower types
  2413 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2414 
  2415 rat_power_0    -> power_0
  2416 rat_power_Suc  -> power_Suc
  2417 realpow_0      -> power_0
  2418 realpow_Suc    -> power_Suc
  2419 complexpow_0   -> power_0
  2420 complexpow_Suc -> power_Suc
  2421 power_poly_0   -> power_0
  2422 power_poly_Suc -> power_Suc
  2423 
  2424 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2425 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2426 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2427 of lemmas from Divides has been generalized from nat to class
  2428 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2429 renames resulting from duplicate elimination:
  2430 
  2431     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2432     zero_dvd_iff ~>         dvd_0_left_iff
  2433     dvd_0 ~>                dvd_0_right
  2434     DIVISION_BY_ZERO_DIV ~> div_by_0
  2435     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2436     mult_div ~>             div_mult_self2_is_id
  2437     mult_mod ~>             mod_mult_self2_is_0
  2438 
  2439 * Theory IntDiv: removed many lemmas that are instances of class-based
  2440 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2441 rename old lemmas as follows:
  2442 
  2443 dvd_diff               -> nat_dvd_diff
  2444 dvd_zminus_iff         -> dvd_minus_iff
  2445 mod_add1_eq            -> mod_add_eq
  2446 mod_mult1_eq           -> mod_mult_right_eq
  2447 mod_mult1_eq'          -> mod_mult_left_eq
  2448 mod_mult_distrib_mod   -> mod_mult_eq
  2449 nat_mod_add_left_eq    -> mod_add_left_eq
  2450 nat_mod_add_right_eq   -> mod_add_right_eq
  2451 nat_mod_div_trivial    -> mod_div_trivial
  2452 nat_mod_mod_trivial    -> mod_mod_trivial
  2453 zdiv_zadd_self1        -> div_add_self1
  2454 zdiv_zadd_self2        -> div_add_self2
  2455 zdiv_zmult_self1       -> div_mult_self2_is_id
  2456 zdiv_zmult_self2       -> div_mult_self1_is_id
  2457 zdvd_triv_left         -> dvd_triv_left
  2458 zdvd_triv_right        -> dvd_triv_right
  2459 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2460 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2461 zmod_zadd_left_eq      -> mod_add_left_eq
  2462 zmod_zadd_right_eq     -> mod_add_right_eq
  2463 zmod_zadd_self1        -> mod_add_self1
  2464 zmod_zadd_self2        -> mod_add_self2
  2465 zmod_zadd1_eq          -> mod_add_eq
  2466 zmod_zdiff1_eq         -> mod_diff_eq
  2467 zmod_zdvd_zmod         -> mod_mod_cancel
  2468 zmod_zmod_cancel       -> mod_mod_cancel
  2469 zmod_zmult_self1       -> mod_mult_self2_is_0
  2470 zmod_zmult_self2       -> mod_mult_self1_is_0
  2471 zmod_1                 -> mod_by_1
  2472 zdiv_1                 -> div_by_1
  2473 zdvd_abs1              -> abs_dvd_iff
  2474 zdvd_abs2              -> dvd_abs_iff
  2475 zdvd_refl              -> dvd_refl
  2476 zdvd_trans             -> dvd_trans
  2477 zdvd_zadd              -> dvd_add
  2478 zdvd_zdiff             -> dvd_diff
  2479 zdvd_zminus_iff        -> dvd_minus_iff
  2480 zdvd_zminus2_iff       -> minus_dvd_iff
  2481 zdvd_zmultD            -> dvd_mult_right
  2482 zdvd_zmultD2           -> dvd_mult_left
  2483 zdvd_zmult_mono        -> mult_dvd_mono
  2484 zdvd_0_right           -> dvd_0_right
  2485 zdvd_0_left            -> dvd_0_left_iff
  2486 zdvd_1_left            -> one_dvd
  2487 zminus_dvd_iff         -> minus_dvd_iff
  2488 
  2489 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2490 
  2491 * The real numbers offer decimal input syntax: 12.34 is translated
  2492 into 1234/10^2. This translation is not reversed upon output.
  2493 
  2494 * Theory Library/Polynomial defines an abstract type 'a poly of
  2495 univariate polynomials with coefficients of type 'a.  In addition to
  2496 the standard ring operations, it also supports div and mod.  Code
  2497 generation is also supported, using list-style constructors.
  2498 
  2499 * Theory Library/Inner_Product defines a class of real_inner for real
  2500 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2501 => real.  Class real_inner is a subclass of real_normed_vector from
  2502 theory RealVector.
  2503 
  2504 * Theory Library/Product_Vector provides instances for the product
  2505 type 'a * 'b of several classes from RealVector and Inner_Product.
  2506 Definitions of addition, subtraction, scalar multiplication, norms,
  2507 and inner products are included.
  2508 
  2509 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2510 addition to the field operations, numerals and case syntax are also
  2511 supported.
  2512 
  2513 * Theory Library/Diagonalize provides constructive version of Cantor's
  2514 first diagonalization argument.
  2515 
  2516 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2517 zlcm (for int); carried together from various gcd/lcm developements in
  2518 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2519 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2520 may recover tupled syntax as follows:
  2521 
  2522     hide (open) const gcd
  2523     abbreviation gcd where
  2524       "gcd == (%(a, b). GCD.gcd a b)"
  2525     notation (output)
  2526       GCD.gcd ("gcd '(_, _')")
  2527 
  2528 The same works for lcm, zgcd, zlcm.
  2529 
  2530 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2531 instantiations for algebraic structures.  Removed some duplicate
  2532 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2533 
  2534 * ML antiquotation @{code} takes a constant as argument and generates
  2535 corresponding code in background and inserts name of the corresponding
  2536 resulting ML value/function/datatype constructor binding in place.
  2537 All occurrences of @{code} with a single ML block are generated
  2538 simultaneously.  Provides a generic and safe interface for
  2539 instrumentalizing code generation.  See
  2540 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2541 In future you ought to refrain from ad-hoc compiling generated SML
  2542 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2543 cannot refer to constants for which user-defined serializations are
  2544 set.  Refer to the corresponding ML counterpart directly in that
  2545 cases.
  2546 
  2547 * Command 'rep_datatype': instead of theorem names the command now
  2548 takes a list of terms denoting the constructors of the type to be
  2549 represented as datatype.  The characteristic theorems have to be
  2550 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2551 have disappeared in favour of existing ones:
  2552 
  2553     unit_induct                 ~> unit.induct
  2554     prod_induct                 ~> prod.induct
  2555     sum_induct                  ~> sum.induct
  2556     Suc_Suc_eq                  ~> nat.inject
  2557     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2558 
  2559 
  2560 *** HOL-Algebra ***
  2561 
  2562 * New locales for orders and lattices where the equivalence relation
  2563 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2564 locales use a record structure with field eq for the equivalence.
  2565 
  2566 * New theory of factorial domains.
  2567 
  2568 * Units_l_inv and Units_r_inv are now simp rules by default.
  2569 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2570 and/or r_inv will now also require deletion of these lemmas.
  2571 
  2572 * Renamed the following theorems, INCOMPATIBILITY:
  2573 
  2574 UpperD ~> Upper_memD
  2575 LowerD ~> Lower_memD
  2576 least_carrier ~> least_closed
  2577 greatest_carrier ~> greatest_closed
  2578 greatest_Lower_above ~> greatest_Lower_below
  2579 one_zero ~> carrier_one_zero
  2580 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2581 
  2582 
  2583 *** HOL-Nominal ***
  2584 
  2585 * Nominal datatypes can now contain type-variables.
  2586 
  2587 * Commands 'nominal_inductive' and 'equivariance' work with local
  2588 theory targets.
  2589 
  2590 * Nominal primrec can now works with local theory targets and its
  2591 specification syntax now conforms to the general format as seen in
  2592 'inductive' etc.
  2593 
  2594 * Method "perm_simp" honours the standard simplifier attributes
  2595 (no_asm), (no_asm_use) etc.
  2596 
  2597 * The new predicate #* is defined like freshness, except that on the
  2598 left hand side can be a set or list of atoms.
  2599 
  2600 * Experimental command 'nominal_inductive2' derives strong induction
  2601 principles for inductive definitions.  In contrast to
  2602 'nominal_inductive', which can only deal with a fixed number of
  2603 binders, it can deal with arbitrary expressions standing for sets of
  2604 atoms to be avoided.  The only inductive definition we have at the
  2605 moment that needs this generalisation is the typing rule for Lets in
  2606 the algorithm W:
  2607 
  2608  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2609  -----------------------------------------------------------------
  2610          Gamma |- Let x be t1 in t2 : T2
  2611 
  2612 In this rule one wants to avoid all the binders that are introduced by
  2613 "close Gamma T1".  We are looking for other examples where this
  2614 feature might be useful.  Please let us know.
  2615 
  2616 
  2617 *** HOLCF ***
  2618 
  2619 * Reimplemented the simplification procedure for proving continuity
  2620 subgoals.  The new simproc is extensible; users can declare additional
  2621 continuity introduction rules with the attribute [cont2cont].
  2622 
  2623 * The continuity simproc now uses a different introduction rule for
  2624 solving continuity subgoals on terms with lambda abstractions.  In
  2625 some rare cases the new simproc may fail to solve subgoals that the
  2626 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2627 Potential INCOMPATIBILITY.
  2628 
  2629 * Command 'fixrec': specification syntax now conforms to the general
  2630 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2631 examples.  INCOMPATIBILITY.
  2632 
  2633 
  2634 *** ZF ***
  2635 
  2636 * Proof of Zorn's Lemma for partial orders.
  2637 
  2638 
  2639 *** ML ***
  2640 
  2641 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2642 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2643 depends on multithreading, so timouts will not work before Poly/ML
  2644 5.2.1!
  2645 
  2646 * High-level support for concurrent ML programming, see
  2647 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2648 particularly convenient to organize independent functional
  2649 computations.  The concept of "synchronized variables" provides a
  2650 higher-order interface for components with shared state, avoiding the
  2651 delicate details of mutexes and condition variables.  (Requires
  2652 Poly/ML 5.2.1 or later.)
  2653 
  2654 * ML bindings produced via Isar commands are stored within the Isar
  2655 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2656 become thread-safe and work with undo as expected (concerning
  2657 top-level bindings, not side-effects on global references).
  2658 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2659 compiler at runtime; really global bindings need to be given outside a
  2660 theory.  (Requires Poly/ML 5.2 or later.)
  2661 
  2662 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2663 context.  Top-level ML bindings are stored within the proof context in
  2664 a purely sequential fashion, disregarding the nested proof structure.
  2665 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2666 proof.  (Requires Poly/ML 5.2 or later.)
  2667 
  2668 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2669 and Method.setup, as well as Isar commands 'attribute_setup' and
  2670 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2671 existing code accordingly, or use plain 'setup' together with old
  2672 Method.add_method.
  2673 
  2674 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2675 to 'a -> thm, while results are always tagged with an authentic oracle
  2676 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2677 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2678 accordingly.  Note that extra performance may be gained by producing
  2679 the cterm carefully, avoiding slow Thm.cterm_of.
  2680 
  2681 * Simplified interface for defining document antiquotations via
  2682 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2683 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2684 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2685 examples.
  2686 
  2687 * More systematic treatment of long names, abstract name bindings, and
  2688 name space operations.  Basic operations on qualified names have been
  2689 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2690 Long_Name.append.  Old type bstring has been mostly replaced by
  2691 abstract type binding (see structure Binding), which supports precise
  2692 qualification by packages and local theory targets, as well as proper
  2693 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2694 bstring values into Binding.name, or better pass through abstract
  2695 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2696 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2697 
  2698 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2699 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2700 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2701 
  2702 * Disposed old type and term read functions (Sign.read_def_typ,
  2703 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2704 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2705 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2706 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2707 resort for legacy applications.
  2708 
  2709 * Disposed old declarations, tactics, tactic combinators that refer to
  2710 the simpset or claset of an implicit theory (such as Addsimps,
  2711 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2712 embedded ML text, or local_simpset_of with a proper context passed as
  2713 explicit runtime argument.
  2714 
  2715 * Rules and tactics that read instantiations (read_instantiate,
  2716 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2717 context, which is required for parsing and type-checking.  Moreover,
  2718 the variables are specified as plain indexnames, not string encodings
  2719 thereof.  INCOMPATIBILITY.
  2720 
  2721 * Generic Toplevel.add_hook interface allows to analyze the result of
  2722 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2723 for theorem dependency output of transactions resulting in a new
  2724 theory state.
  2725 
  2726 * ML antiquotations: block-structured compilation context indicated by
  2727 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2728 
  2729   @{binding name}                         - basic name binding
  2730   @{let ?pat = term}                      - term abbreviation (HO matching)
  2731   @{note name = fact}                     - fact abbreviation
  2732   @{thm fact}                             - singleton fact (with attributes)
  2733   @{thms fact}                            - general fact (with attributes)
  2734   @{lemma prop by method}                 - singleton goal
  2735   @{lemma prop by meth1 meth2}            - singleton goal
  2736   @{lemma prop1 ... propN by method}      - general goal
  2737   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2738   @{lemma (open) ...}                     - open derivation
  2739 
  2740 
  2741 *** System ***
  2742 
  2743 * The Isabelle "emacs" tool provides a specific interface to invoke
  2744 Proof General / Emacs, with more explicit failure if that is not
  2745 installed (the old isabelle-interface script silently falls back on
  2746 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2747 installation location of the Proof General distribution.
  2748 
  2749 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2750 the Isabelle process into a JVM/Scala application.  See
  2751 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2752 process wrapper has been discontinued.)
  2753 
  2754 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2755 
  2756 * Various status messages (with exact source position information) are
  2757 emitted, if proper markup print mode is enabled.  This allows
  2758 user-interface components to provide detailed feedback on internal
  2759 prover operations.
  2760 
  2761 
  2762 
  2763 New in Isabelle2008 (June 2008)
  2764 -------------------------------
  2765 
  2766 *** General ***
  2767 
  2768 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2769 and updated, with formally checked references as hyperlinks.
  2770 
  2771 * Theory loader: use_thy (and similar operations) no longer set the
  2772 implicit ML context, which was occasionally hard to predict and in
  2773 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2774 provides a proper context already.
  2775 
  2776 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2777 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2778 'use' within a theory file will do the job.
  2779 
  2780 * Name space merge now observes canonical order, i.e. the second space
  2781 is inserted into the first one, while existing entries in the first
  2782 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2783 swap theory imports.
  2784 
  2785 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2786 INCOMPATIBILITY in identifier syntax etc.
  2787 
  2788 * Outer syntax: string tokens no longer admit escaped white space,
  2789 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2790 white space without escapes.
  2791 
  2792 * Outer syntax: string tokens may contain arbitrary character codes
  2793 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2794 "foo_bar".
  2795 
  2796 
  2797 *** Pure ***
  2798 
  2799 * Context-dependent token translations.  Default setup reverts locally
  2800 fixed variables, and adds hilite markup for undeclared frees.
  2801 
  2802 * Unused theorems can be found using the new command 'unused_thms'.
  2803 There are three ways of invoking it:
  2804 
  2805 (1) unused_thms
  2806      Only finds unused theorems in the current theory.
  2807 
  2808 (2) unused_thms thy_1 ... thy_n -
  2809      Finds unused theorems in the current theory and all of its ancestors,
  2810      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2811 
  2812 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2813      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2814      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2815      their ancestors.
  2816 
  2817 In order to increase the readability of the list produced by
  2818 unused_thms, theorems that have been created by a particular instance
  2819 of a theory command such as 'inductive' or 'function' are considered
  2820 to belong to the same "group", meaning that if at least one theorem in
  2821 this group is used, the other theorems in the same group are no longer
  2822 reported as unused.  Moreover, if all theorems in the group are
  2823 unused, only one theorem in the group is displayed.
  2824 
  2825 Note that proof objects have to be switched on in order for
  2826 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2827 usually the case when using Proof General with the default settings).
  2828 
  2829 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2830 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2831 duplicate fact bindings, or even accidental fact duplications.  Note
  2832 that tools may maintain dynamically scoped facts systematically, using
  2833 PureThy.add_thms_dynamic.
  2834 
  2835 * Command 'hide' now allows to hide from "fact" name space as well.
  2836 
  2837 * Eliminated destructive theorem database, simpset, claset, and
  2838 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2839 update of theories within ML code.
  2840 
  2841 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2842 INCOMPATIBILITY, object-logics depending on former Pure require
  2843 additional setup PureThy.old_appl_syntax_setup; object-logics
  2844 depending on former CPure need to refer to Pure.
  2845 
  2846 * Commands 'use' and 'ML' are now purely functional, operating on
  2847 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2848 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2849 INCOMPATIBILITY.
  2850 
  2851 * Command 'setup': discontinued implicit version with ML reference.
  2852 
  2853 * Instantiation target allows for simultaneous specification of class
  2854 instance operations together with an instantiation proof.
  2855 Type-checking phase allows to refer to class operations uniformly.
  2856 See src/HOL/Complex/Complex.thy for an Isar example and
  2857 src/HOL/Library/Eval.thy for an ML example.
  2858 
  2859 * Indexing of literal facts: be more serious about including only
  2860 facts from the visible specification/proof context, but not the
  2861 background context (locale etc.).  Affects `prop` notation and method
  2862 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2863 situations.
  2864 
  2865 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2866 "(open)" option, which used to expose internal bound variables to the
  2867 proof text.
  2868 
  2869 * Isar statements: removed obsolete case "rule_context".
  2870 INCOMPATIBILITY, better use explicit fixes/assumes.
  2871 
  2872 * Locale proofs: default proof step now includes 'unfold_locales';
  2873 hence 'proof' without argument may be used to unfold locale
  2874 predicates.
  2875 
  2876 
  2877 *** Document preparation ***
  2878 
  2879 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2880 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2881 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2882 spot); renamed link color from "darkblue" to "linkcolor" (default
  2883 value unchanged, can be redefined via \definecolor); no longer sets
  2884 "a4paper" option (unnecessary or even intrusive).
  2885 
  2886 * Antiquotation @{lemma A method} proves proposition A by the given
  2887 method (either a method name or a method name plus (optional) method
  2888 arguments in parentheses) and prints A just like @{prop A}.
  2889 
  2890 
  2891 *** HOL ***
  2892 
  2893 * New primrec package.  Specification syntax conforms in style to
  2894 definition/function/....  No separate induction rule is provided.  The
  2895 "primrec" command distinguishes old-style and new-style specifications
  2896 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2897 When adjusting theories, beware: constants stemming from new-style
  2898 primrec specifications have authentic syntax.
  2899 
  2900 * Metis prover is now an order of magnitude faster, and also works
  2901 with multithreading.
  2902 
  2903 * Metis: the maximum number of clauses that can be produced from a
  2904 theorem is now given by the attribute max_clauses.  Theorems that
  2905 exceed this number are ignored, with a warning printed.
  2906 
  2907 * Sledgehammer no longer produces structured proofs by default. To
  2908 enable, declare [[sledgehammer_full = true]].  Attributes
  2909 reconstruction_modulus, reconstruction_sorts renamed
  2910 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2911 
  2912 * Method "induct_scheme" derives user-specified induction rules
  2913 from well-founded induction and completeness of patterns. This factors
  2914 out some operations that are done internally by the function package
  2915 and makes them available separately.  See
  2916 src/HOL/ex/Induction_Scheme.thy for examples.
  2917 
  2918 * More flexible generation of measure functions for termination
  2919 proofs: Measure functions can be declared by proving a rule of the
  2920 form "is_measure f" and giving it the [measure_function] attribute.
  2921 The "is_measure" predicate is logically meaningless (always true), and
  2922 just guides the heuristic.  To find suitable measure functions, the
  2923 termination prover sets up the goal "is_measure ?f" of the appropriate
  2924 type and generates all solutions by prolog-style backwards proof using
  2925 the declared rules.
  2926 
  2927 This setup also deals with rules like 
  2928 
  2929   "is_measure f ==> is_measure (list_size f)"
  2930 
  2931 which accommodates nested datatypes that recurse through lists.
  2932 Similar rules are predeclared for products and option types.
  2933 
  2934 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2935 
  2936   INCOMPATIBILITIES:
  2937 
  2938   - Definitions of overloaded constants on sets have to be replaced by
  2939     definitions on => and bool.
  2940 
  2941   - Some definitions of overloaded operators on sets can now be proved
  2942     using the definitions of the operators on => and bool.  Therefore,
  2943     the following theorems have been renamed:
  2944 
  2945       subset_def   -> subset_eq
  2946       psubset_def  -> psubset_eq
  2947       set_diff_def -> set_diff_eq
  2948       Compl_def    -> Compl_eq
  2949       Sup_set_def  -> Sup_set_eq
  2950       Inf_set_def  -> Inf_set_eq
  2951       sup_set_def  -> sup_set_eq
  2952       inf_set_def  -> inf_set_eq
  2953 
  2954   - Due to the incompleteness of the HO unification algorithm, some
  2955     rules such as subst may require manual instantiation, if some of
  2956     the unknowns in the rule is a set.
  2957 
  2958   - Higher order unification and forward proofs:
  2959     The proof pattern
  2960 
  2961       have "P (S::'a set)" <...>
  2962       then have "EX S. P S" ..
  2963 
  2964     no longer works (due to the incompleteness of the HO unification
  2965     algorithm) and must be replaced by the pattern
  2966 
  2967       have "EX S. P S"
  2968       proof
  2969         show "P S" <...>
  2970       qed
  2971 
  2972   - Calculational reasoning with subst (or similar rules):
  2973     The proof pattern
  2974 
  2975       have "P (S::'a set)" <...>
  2976       also have "S = T" <...>
  2977       finally have "P T" .
  2978 
  2979     no longer works (for similar reasons as the previous example) and
  2980     must be replaced by something like
  2981 
  2982       have "P (S::'a set)" <...>
  2983       moreover have "S = T" <...>
  2984       ultimately have "P T" by simp
  2985 
  2986   - Tactics or packages written in ML code:
  2987     Code performing pattern matching on types via
  2988 
  2989       Type ("set", [T]) => ...
  2990 
  2991     must be rewritten. Moreover, functions like strip_type or
  2992     binder_types no longer return the right value when applied to a
  2993     type of the form
  2994 
  2995       T1 => ... => Tn => U => bool
  2996 
  2997     rather than
  2998 
  2999       T1 => ... => Tn => U set
  3000 
  3001 * Merged theories Wellfounded_Recursion, Accessible_Part and
  3002 Wellfounded_Relations to theory Wellfounded.
  3003 
  3004 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  3005 
  3006 * Class finite no longer treats UNIV as class parameter.  Use class
  3007 enum from theory Library/Enum instead to achieve a similar effect.
  3008 INCOMPATIBILITY.
  3009 
  3010 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  3011 and "Cons".  INCOMPATIBILITY.
  3012 
  3013 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  3014 Potential INCOMPATIBILITY.
  3015 
  3016 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  3017 injective_fst_snd removed, use split_eta and prod_eqI instead.
  3018 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  3019 
  3020 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  3021 the same name in theory Orderings:
  3022 
  3023   less_trans
  3024   less_linear
  3025   le_imp_less_or_eq
  3026   le_less_trans
  3027   less_le_trans
  3028   less_not_sym
  3029   less_asym
  3030 
  3031 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  3032 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  3033 and different variable names.
  3034 
  3035 * Library/Option_ord.thy: Canonical order on option type.
  3036 
  3037 * Library/RBT.thy: Red-black trees, an efficient implementation of
  3038 finite maps.
  3039 
  3040 * Library/Countable.thy: Type class for countable types.
  3041 
  3042 * Theory Int: The representation of numerals has changed.  The infix
  3043 operator BIT and the bit datatype with constructors B0 and B1 have
  3044 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  3045 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  3046 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  3047 accordingly.
  3048 
  3049 * Theory Nat: definition of <= and < on natural numbers no longer
  3050 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  3051 le_def and less_def have disappeared.  Consider lemmas not_less
  3052 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  3053 
  3054 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  3055 (whose purpose mainly is for various fold_set functionals) have been
  3056 abandoned in favor of the existing algebraic classes
  3057 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  3058 lower_semilattice (resp. upper_semilattice) and linorder.
  3059 INCOMPATIBILITY.
  3060 
  3061 * Theory Transitive_Closure: induct and cases rules now declare proper
  3062 case_names ("base" and "step").  INCOMPATIBILITY.
  3063 
  3064 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  3065 lattices.  The form set-specific version is available as
  3066 Inductive.lfp_ordinal_induct_set.
  3067 
  3068 * Renamed theorems "power.simps" to "power_int.simps".
  3069 INCOMPATIBILITY.
  3070 
  3071 * Class semiring_div provides basic abstract properties of semirings
  3072 with division and modulo operations.  Subsumes former class dvd_mod.
  3073 
  3074 * Merged theories IntDef, Numeral and IntArith into unified theory
  3075 Int.  INCOMPATIBILITY.
  3076 
  3077 * Theory Library/Code_Index: type "index" now represents natural
  3078 numbers rather than integers.  INCOMPATIBILITY.
  3079 
  3080 * New class "uminus" with operation "uminus" (split of from class
  3081 "minus" which now only has operation "minus", binary).
  3082 INCOMPATIBILITY.
  3083 
  3084 * Constants "card", "internal_split", "option_map" now with authentic
  3085 syntax.  INCOMPATIBILITY.
  3086 
  3087 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3088 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3089 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3090 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3091 Sup_set_def, le_def, less_def, option_map_def now with object
  3092 equality.  INCOMPATIBILITY.
  3093 
  3094 * Records. Removed K_record, and replaced it by pure lambda term
  3095 %x. c. The simplifier setup is now more robust against eta expansion.
  3096 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3097 
  3098 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3099 
  3100 * Library/ListVector: new theory of arithmetic vector operations.
  3101 
  3102 * Library/Order_Relation: new theory of various orderings as sets of
  3103 pairs.  Defines preorders, partial orders, linear orders and
  3104 well-orders on sets and on types.
  3105 
  3106 
  3107 *** ZF ***
  3108 
  3109 * Renamed some theories to allow to loading both ZF and HOL in the
  3110 same session:
  3111 
  3112   Datatype  -> Datatype_ZF
  3113   Inductive -> Inductive_ZF
  3114   Int       -> Int_ZF
  3115   IntDiv    -> IntDiv_ZF
  3116   Nat       -> Nat_ZF
  3117   List      -> List_ZF
  3118   Main      -> Main_ZF
  3119 
  3120 INCOMPATIBILITY: ZF theories that import individual theories below
  3121 Main might need to be adapted.  Regular theory Main is still
  3122 available, as trivial extension of Main_ZF.
  3123 
  3124 
  3125 *** ML ***
  3126 
  3127 * ML within Isar: antiquotation @{const name} or @{const
  3128 name(typargs)} produces statically-checked Const term.
  3129 
  3130 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3131 (of the same name).  Removed obsolete print command.
  3132 
  3133 * Removed obsolete "use_legacy_bindings" function.
  3134 
  3135 * The ``print mode'' is now a thread-local value derived from a global
  3136 template (the former print_mode reference), thus access becomes
  3137 non-critical.  The global print_mode reference is for session
  3138 management only; user-code should use print_mode_value,
  3139 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3140 
  3141 * Functions system/system_out provide a robust way to invoke external
  3142 shell commands, with propagation of interrupts (requires Poly/ML
  3143 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3144 
  3145 
  3146 *** System ***
  3147 
  3148 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3149 in accordance with Proof General 3.7, which prefers GNU emacs.
  3150 
  3151 * isatool tty runs Isabelle process with plain tty interaction;
  3152 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3153 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3154 
  3155 * isatool browser now works with Cygwin as well, using general
  3156 "javapath" function defined in Isabelle process environment.
  3157 
  3158 * YXML notation provides a simple and efficient alternative to
  3159 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3160 isatool yxml as described in the Isabelle system manual.
  3161 
  3162 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3163 provides general wrapper for managing an Isabelle process in a robust
  3164 fashion, with ``cooked'' output from stdin/stderr.
  3165 
  3166 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3167 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3168 
  3169 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3170 way of changing the user's settings is via
  3171 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3172 script.
  3173 
  3174 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3175 cores of the underlying machine, which is a good starting point for
  3176 optimal performance tuning.  The corresponding usedir option -M allows
  3177 "max" as an alias for "0".  WARNING: does not work on certain versions
  3178 of Mac OS (with Poly/ML 5.1).
  3179 
  3180 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3181 adverse effect of Isabelle flooding interactive front-ends (notably
  3182 ProofGeneral / XEmacs).
  3183 
  3184 
  3185 
  3186 New in Isabelle2007 (November 2007)
  3187 -----------------------------------
  3188 
  3189 *** General ***
  3190 
  3191 * More uniform information about legacy features, notably a
  3192 warning/error of "Legacy feature: ...", depending on the state of the
  3193 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3194 legacy features will disappear eventually.
  3195 
  3196 * Theory syntax: the header format ``theory A = B + C:'' has been
  3197 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3198 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3199 
  3200 * Theory syntax: the old non-Isar theory file format has been
  3201 discontinued altogether.  Note that ML proof scripts may still be used
  3202 with Isar theories; migration is usually quite simple with the ML
  3203 function use_legacy_bindings.  INCOMPATIBILITY.
  3204 
  3205 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3206 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3207 quotes.
  3208 
  3209 * Theory loader: be more serious about observing the static theory
  3210 header specifications (including optional directories), but not the
  3211 accidental file locations of previously successful loads.  The strict
  3212 update policy of former update_thy is now already performed by
  3213 use_thy, so the former has been removed; use_thys updates several
  3214 theories simultaneously, just as 'imports' within a theory header
  3215 specification, but without merging the results.  Potential
  3216 INCOMPATIBILITY: may need to refine theory headers and commands
  3217 ROOT.ML which depend on load order.
  3218 
  3219 * Theory loader: optional support for content-based file
  3220 identification, instead of the traditional scheme of full physical
  3221 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3222 (cf. the system manual).  The new scheme allows to work with
  3223 non-finished theories in persistent session images, such that source
  3224 files may be moved later on without requiring reloads.
  3225 
  3226 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3227 file (with the same base name as the theory) are considered a legacy
  3228 feature, which will disappear eventually. Even now, the theory loader
  3229 no longer maintains dependencies on such files.
  3230 
  3231 * Syntax: the scope for resolving ambiguities via type-inference is
  3232 now limited to individual terms, instead of whole simultaneous
  3233 specifications as before. This greatly reduces the complexity of the
  3234 syntax module and improves flexibility by separating parsing and
  3235 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3236 'fixes' etc.) are required in rare situations.
  3237 
  3238 * Syntax: constants introduced by new-style packages ('definition',
  3239 'abbreviation' etc.) are passed through the syntax module in
  3240 ``authentic mode''. This means that associated mixfix annotations
  3241 really stick to such constants, independently of potential name space
  3242 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3243 trees are represented slightly differently, may need to adapt syntax
  3244 translations accordingly. Use CONST marker in 'translations' and
  3245 @{const_syntax} antiquotation in 'parse_translation' etc.
  3246 
  3247 * Legacy goal package: reduced interface to the bare minimum required
  3248 to keep existing proof scripts running.  Most other user-level
  3249 functions are now part of the OldGoals structure, which is *not* open
  3250 by default (consider isatool expandshort before open OldGoals).
  3251 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3252 these tend to cause confusion about the actual goal (!) context being
  3253 used here, which is not necessarily the same as the_context().
  3254 
  3255 * Command 'find_theorems': supports "*" wild-card in "name:"
  3256 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3257 support a specific search form (see ProofGeneral/CHANGES).
  3258 
  3259 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3260 by default, which means that "prems" (and also "fixed variables") are
  3261 suppressed from proof state output.  Note that the ProofGeneral
  3262 settings mechanism allows to change and save options persistently, but
  3263 older versions of Isabelle will fail to start up if a negative prems
  3264 limit is imposed.
  3265 
  3266 * Local theory targets may be specified by non-nested blocks of
  3267 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3268 contain definitions, theorems etc., including any derived mechanism
  3269 that has been implemented on top of these primitives.  This concept
  3270 generalizes the existing ``theorem (in ...)'' towards more versatility
  3271 and scalability.
  3272 
  3273 * Proof General interface: proper undo of final 'end' command;
  3274 discontinued Isabelle/classic mode (ML proof scripts).
  3275 
  3276 
  3277 *** Document preparation ***
  3278 
  3279 * Added antiquotation @{theory name} which prints the given name,
  3280 after checking that it refers to a valid ancestor theory in the
  3281 current context.
  3282 
  3283 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3284 check the given source text as ML type/structure, printing verbatim.
  3285 
  3286 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3287 "c args == rhs" given in the current context.  (Any number of
  3288 arguments may be given on the LHS.)
  3289 
  3290 
  3291 *** Pure ***
  3292 
  3293 * The 'class' package offers a combination of axclass and locale to
  3294 achieve Haskell-like type classes in Isabelle.  Definitions and
  3295 theorems within a class context produce both relative results (with
  3296 implicit parameters according to the locale context), and polymorphic
  3297 constants with qualified polymorphism (according to the class
  3298 context).  Within the body context of a 'class' target, a separate
  3299 syntax layer ("user space type system") takes care of converting
  3300 between global polymorphic consts and internal locale representation.
  3301 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3302 "isatool doc classes" provides a tutorial.
  3303 
  3304 * Generic code generator framework allows to generate executable
  3305 code for ML and Haskell (including Isabelle classes).  A short usage
  3306 sketch:
  3307 
  3308     internal compilation:
  3309         export_code <list of constants (term syntax)> in SML
  3310     writing SML code to a file:
  3311         export_code <list of constants (term syntax)> in SML <filename>
  3312     writing OCaml code to a file:
  3313         export_code <list of constants (term syntax)> in OCaml <filename>
  3314     writing Haskell code to a bunch of files:
  3315         export_code <list of constants (term syntax)> in Haskell <filename>
  3316 
  3317     evaluating closed propositions to True/False using code generation:
  3318         method ``eval''
  3319 
  3320 Reasonable default setup of framework in HOL.
  3321 
  3322 Theorem attributs for selecting and transforming function equations theorems:
  3323 
  3324     [code fun]:        select a theorem as function equation for a specific constant
  3325     [code fun del]:    deselect a theorem as function equation for a specific constant
  3326     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3327     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3328 
  3329 User-defined serializations (target in {SML, OCaml, Haskell}):
  3330 
  3331     code_const <and-list of constants (term syntax)>
  3332       {(target) <and-list of const target syntax>}+
  3333 
  3334     code_type <and-list of type constructors>
  3335       {(target) <and-list of type target syntax>}+
  3336 
  3337     code_instance <and-list of instances>
  3338       {(target)}+
  3339         where instance ::= <type constructor> :: <class>
  3340 
  3341     code_class <and_list of classes>
  3342       {(target) <and-list of class target syntax>}+
  3343         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3344 
  3345 code_instance and code_class only are effective to target Haskell.
  3346 
  3347 For example usage see src/HOL/ex/Codegenerator.thy and
  3348 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3349 generation from Isabelle/HOL theories is available via "isatool doc
  3350 codegen".
  3351 
  3352 * Code generator: consts in 'consts_code' Isar commands are now
  3353 referred to by usual term syntax (including optional type
  3354 annotations).
  3355 
  3356 * Command 'no_translations' removes translation rules from theory
  3357 syntax.
  3358 
  3359 * Overloaded definitions are now actually checked for acyclic
  3360 dependencies.  The overloading scheme is slightly more general than
  3361 that of Haskell98, although Isabelle does not demand an exact
  3362 correspondence to type class and instance declarations.
  3363 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3364 exotic versions of overloading -- at the discretion of the user!
  3365 
  3366 Polymorphic constants are represented via type arguments, i.e. the
  3367 instantiation that matches an instance against the most general
  3368 declaration given in the signature.  For example, with the declaration
  3369 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3370 as c(nat).  Overloading is essentially simultaneous structural
  3371 recursion over such type arguments.  Incomplete specification patterns
  3372 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3373 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3374 Command 'print_theory' outputs the normalized system of recursive
  3375 equations, see section "definitions".
  3376 
  3377 * Configuration options are maintained within the theory or proof
  3378 context (with name and type bool/int/string), providing a very simple
  3379 interface to a poor-man's version of general context data.  Tools may
  3380 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3381 these values using Config.get etc.  Users may change options via an
  3382 associated attribute of the same name.  This form of context
  3383 declaration works particularly well with commands 'declare' or
  3384 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3385 very easy to avoid global references, which would not observe Isar
  3386 toplevel undo/redo and fail to work with multithreading.
  3387 
  3388 Various global ML references of Pure and HOL have been turned into
  3389 configuration options:
  3390 
  3391   Unify.search_bound		unify_search_bound
  3392   Unify.trace_bound		unify_trace_bound
  3393   Unify.trace_simp		unify_trace_simp
  3394   Unify.trace_types		unify_trace_types
  3395   Simplifier.simp_depth_limit	simp_depth_limit
  3396   Blast.depth_limit		blast_depth_limit
  3397   DatatypeProp.dtK		datatype_distinctness_limit
  3398   fast_arith_neq_limit  	fast_arith_neq_limit
  3399   fast_arith_split_limit	fast_arith_split_limit
  3400 
  3401 * Named collections of theorems may be easily installed as context
  3402 data using the functor NamedThmsFun (see also
  3403 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3404 attributes; there is also a toplevel print command.  This facility is
  3405 just a common case of general context data, which is the preferred way
  3406 for anything more complex than just a list of facts in canonical
  3407 order.
  3408 
  3409 * Isar: command 'declaration' augments a local theory by generic
  3410 declaration functions written in ML.  This enables arbitrary content
  3411 being added to the context, depending on a morphism that tells the
  3412 difference of the original declaration context wrt. the application
  3413 context encountered later on.
  3414 
  3415 * Isar: proper interfaces for simplification procedures.  Command
  3416 'simproc_setup' declares named simprocs (with match patterns, and body
  3417 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3418 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3419 
  3420 * Isar: an extra pair of brackets around attribute declarations
  3421 abbreviates a theorem reference involving an internal dummy fact,
  3422 which will be ignored later --- only the effect of the attribute on
  3423 the background context will persist.  This form of in-place
  3424 declarations is particularly useful with commands like 'declare' and
  3425 'using', for example ``have A using [[simproc a]] by simp''.
  3426 
  3427 * Isar: method "assumption" (and implicit closing of subproofs) now
  3428 takes simple non-atomic goal assumptions into account: after applying
  3429 an assumption as a rule the resulting subgoals are solved by atomic
  3430 assumption steps.  This is particularly useful to finish 'obtain'
  3431 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3432 without referring to the original premise "!!x. P x ==> thesis" in the
  3433 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3434 more permissive.
  3435 
  3436 * Isar: implicit use of prems from the Isar proof context is
  3437 considered a legacy feature.  Common applications like ``have A .''
  3438 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3439 referencing facts explicitly here improves readability and
  3440 maintainability of proof texts.
  3441 
  3442 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3443 the obtained context from the course of reasoning!  For example:
  3444 
  3445   assume "EX x y. A x & B y"   -- "any previous fact"
  3446   then guess x and y by clarify
  3447 
  3448 This technique is potentially adventurous, depending on the facts and
  3449 proof tools being involved here.
  3450 
  3451 * Isar: known facts from the proof context may be specified as literal
  3452 propositions, using ASCII back-quote syntax.  This works wherever
  3453 named facts used to be allowed so far, in proof commands, proof
  3454 methods, attributes etc.  Literal facts are retrieved from the context
  3455 according to unification of type and term parameters.  For example,
  3456 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3457 theorems in the current context, then these are valid literal facts:
  3458 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3459 
  3460 There is also a proof method "fact" which does the same composition
  3461 for explicit goal states, e.g. the following proof texts coincide with
  3462 certain special cases of literal facts:
  3463 
  3464   have "A" by fact                 ==  note `A`
  3465   have "A ==> B" by fact           ==  note `A ==> B`
  3466   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3467   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3468 
  3469 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3470 outer syntax.  Thus symbolic identifiers may be used without
  3471 additional white space in declarations like this: ``assume *: A''.
  3472 
  3473 * Isar: 'print_facts' prints all local facts of the current context,
  3474 both named and unnamed ones.
  3475 
  3476 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3477 
  3478   def x == "t" and y == "u"
  3479 
  3480 * Isar: added command 'unfolding', which is structurally similar to
  3481 'using', but affects both the goal state and facts by unfolding given
  3482 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3483 'unfolded' attribute may be replaced by first-class proof text.
  3484 
  3485 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3486 and command 'unfolding' now all support object-level equalities
  3487 (potentially conditional).  The underlying notion of rewrite rule is
  3488 analogous to the 'rule_format' attribute, but *not* that of the
  3489 Simplifier (which is usually more generous).
  3490 
  3491 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3492 premises of a theorem by n. Useful in conjunction with drule.
  3493 
  3494 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3495 method expression within a sandbox consisting of the first N
  3496 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3497 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3498 simplifies all new goals that emerge from applying rule foo to the
  3499 originally first one.
  3500 
  3501 * Isar: schematic goals are no longer restricted to higher-order
  3502 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3503 expected.
  3504 
  3505 * Isar: the conclusion of a long theorem statement is now either
  3506 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3507 (essentially a disjunction of cases with local parameters and
  3508 assumptions).  The latter allows to express general elimination rules
  3509 adequately; in this notation common elimination rules look like this:
  3510 
  3511   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3512     assumes "EX x. P x"
  3513     obtains x where "P x"
  3514 
  3515   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3516     assumes "A & B"
  3517     obtains A and B
  3518 
  3519   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3520     assumes "A | B"
  3521     obtains
  3522       A
  3523     | B
  3524 
  3525 The subsequent classical rules even refer to the formal "thesis"
  3526 explicitly:
  3527 
  3528   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3529     obtains "~ thesis"
  3530 
  3531   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3532     obtains "thesis ==> something"
  3533 
  3534 The actual proof of an 'obtains' statement is analogous to that of the
  3535 Isar proof element 'obtain', only that there may be several cases.
  3536 Optional case names may be specified in parentheses; these will be
  3537 available both in the present proof and as annotations in the
  3538 resulting rule, for later use with the 'cases' method (cf. attribute
  3539 case_names).
  3540 
  3541 * Isar: the assumptions of a long theorem statement are available as
  3542 "assms" fact in the proof context.  This is more appropriate than the
  3543 (historical) "prems", which refers to all assumptions of the current
  3544 context, including those from the target locale, proof body etc.
  3545 
  3546 * Isar: 'print_statement' prints theorems from the current theory or
  3547 proof context in long statement form, according to the syntax of a
  3548 top-level lemma.
  3549 
  3550 * Isar: 'obtain' takes an optional case name for the local context
  3551 introduction rule (default "that").
  3552 
  3553 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3554 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3555 to occur.
  3556 
  3557 * Pure: syntax "CONST name" produces a fully internalized constant
  3558 according to the current context.  This is particularly useful for
  3559 syntax translations that should refer to internal constant
  3560 representations independently of name spaces.
  3561 
  3562 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3563 instead of "FOO ". This allows multiple binder declarations to coexist
  3564 in the same context.  INCOMPATIBILITY.
  3565 
  3566 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3567 primitive that also works in a locale context (both for constants and
  3568 fixed variables). Type declaration and internal syntactic representation
  3569 of given constants retrieved from the context. Likewise, the
  3570 'no_notation' command allows to remove given syntax annotations from the
  3571 current context.
  3572 
  3573 * Isar/locales: new derived specification elements 'axiomatization',
  3574 'definition', 'abbreviation', which support type-inference, admit
  3575 object-level specifications (equality, equivalence).  See also the
  3576 isar-ref manual.  Examples:
  3577 
  3578   axiomatization
  3579     eq  (infix "===" 50) where
  3580     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3581 
  3582   definition "f x y = x + y + 1"
  3583   definition g where "g x = f x x"
  3584 
  3585   abbreviation
  3586     neq  (infix "=!=" 50) where
  3587     "x =!= y == ~ (x === y)"
  3588 
  3589 These specifications may be also used in a locale context.  Then the
  3590 constants being introduced depend on certain fixed parameters, and the
  3591 constant name is qualified by the locale base name.  An internal
  3592 abbreviation takes care for convenient input and output, making the
  3593 parameters implicit and using the original short name.  See also
  3594 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3595 entities from a monomorphic theory.
  3596 
  3597 Presently, abbreviations are only available 'in' a target locale, but
  3598 not inherited by general import expressions.  Also note that
  3599 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3600 'translations' in common applications.  The "no_abbrevs" print mode
  3601 prevents folding of abbreviations in term output.
  3602 
  3603 Concrete syntax is attached to specified constants in internal form,
  3604 independently of name spaces.  The parse tree representation is
  3605 slightly different -- use 'notation' instead of raw 'syntax', and
  3606 'translations' with explicit "CONST" markup to accommodate this.
  3607 
  3608 * Pure/Isar: unified syntax for new-style specification mechanisms
  3609 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3610 full type inference and dummy patterns ("_").  For example:
  3611 
  3612   definition "K x _ = x"
  3613 
  3614   inductive conj for A B
  3615   where "A ==> B ==> conj A B"
  3616 
  3617 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3618 the current context.  Print mode "no_abbrevs" prevents inversion of
  3619 abbreviations on output.
  3620 
  3621 * Isar/locales: improved parameter handling: use of locales "var" and
  3622 "struct" no longer necessary; - parameter renamings are no longer
  3623 required to be injective.  For example, this allows to define
  3624 endomorphisms as locale endom = homom mult mult h.
  3625 
  3626 * Isar/locales: changed the way locales with predicates are defined.
  3627 Instead of accumulating the specification, the imported expression is
  3628 now an interpretation.  INCOMPATIBILITY: different normal form of
  3629 locale expressions.  In particular, in interpretations of locales with
  3630 predicates, goals repesenting already interpreted fragments are not
  3631 removed automatically.  Use methods `intro_locales' and
  3632 `unfold_locales'; see below.
  3633 
  3634 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3635 provide backward reasoning on locales predicates.  The methods are
  3636 aware of interpretations and discharge corresponding goals.
  3637 `intro_locales' is less aggressive then `unfold_locales' and does not
  3638 unfold predicates to assumptions.
  3639 
  3640 * Isar/locales: the order in which locale fragments are accumulated
  3641 has changed.  This enables to override declarations from fragments due
  3642 to interpretations -- for example, unwanted simp rules.
  3643 
  3644 * Isar/locales: interpretation in theories and proof contexts has been
  3645 extended.  One may now specify (and prove) equations, which are
  3646 unfolded in interpreted theorems.  This is useful for replacing
  3647 defined concepts (constants depending on locale parameters) by
  3648 concepts already existing in the target context.  Example:
  3649 
  3650   interpretation partial_order ["op <= :: [int, int] => bool"]
  3651     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3652 
  3653 Typically, the constant `partial_order.less' is created by a
  3654 definition specification element in the context of locale
  3655 partial_order.
  3656 
  3657 * Method "induct": improved internal context management to support
  3658 local fixes and defines on-the-fly. Thus explicit meta-level
  3659 connectives !!  and ==> are rarely required anymore in inductive goals
  3660 (using object-logic connectives for this purpose has been long
  3661 obsolete anyway). Common proof patterns are explained in
  3662 src/HOL/Induct/Common_Patterns.thy, see also
  3663 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3664 examples.
  3665 
  3666 * Method "induct": improved handling of simultaneous goals. Instead of
  3667 introducing object-level conjunction, the statement is now split into
  3668 several conclusions, while the corresponding symbolic cases are nested
  3669 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3670 see src/HOL/Induct/Common_Patterns.thy, for example.
  3671 
  3672 * Method "induct": mutual induction rules are now specified as a list
  3673 of rule sharing the same induction cases. HOL packages usually provide
  3674 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3675 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3676 mutual induction rules differently, i.e. like this:
  3677 
  3678   (induct rule: foo_bar.inducts)
  3679   (induct set: foo bar)
  3680   (induct pred: foo bar)
  3681   (induct type: foo bar)
  3682 
  3683 The ML function ProjectRule.projections turns old-style rules into the
  3684 new format.
  3685 
  3686 * Method "coinduct": dual of induction, see
  3687 src/HOL/Library/Coinductive_List.thy for various examples.
  3688 
  3689 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3690 considered a legacy feature.
  3691 
  3692 * Attribute "symmetric" produces result with standardized schematic
  3693 variables (index 0).  Potential INCOMPATIBILITY.
  3694 
  3695 * Simplifier: by default the simplifier trace only shows top level
  3696 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3697 default. Thus there is less danger of being flooded by the trace. The
  3698 trace indicates where parts have been suppressed.
  3699   
  3700 * Provers/classical: removed obsolete classical version of elim_format
  3701 attribute; classical elim/dest rules are now treated uniformly when
  3702 manipulating the claset.
  3703 
  3704 * Provers/classical: stricter checks to ensure that supplied intro,
  3705 dest and elim rules are well-formed; dest and elim rules must have at
  3706 least one premise.
  3707 
  3708 * Provers/classical: attributes dest/elim/intro take an optional
  3709 weight argument for the rule (just as the Pure versions).  Weights are
  3710 ignored by automated tools, but determine the search order of single
  3711 rule steps.
  3712 
  3713 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3714 where the body does not mention the bound variable.  Note that dummy
  3715 patterns implicitly depend on their context of bounds, which makes
  3716 "{_. _}" match any set comprehension as expected.  Potential
  3717 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3718 constant "_idtdummy" in the binding position.
  3719 
  3720 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3721 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3722 for example "A -> B" => "Pi A (%_. B)".
  3723 
  3724 * Pure: 'class_deps' command visualizes the subclass relation, using
  3725 the graph browser tool.
  3726 
  3727 * Pure: 'print_theory' now suppresses certain internal declarations by
  3728 default; use '!' option for full details.
  3729 
  3730 
  3731 *** HOL ***
  3732 
  3733 * Method "metis" proves goals by applying the Metis general-purpose
  3734 resolution prover (see also http://gilith.com/software/metis/).
  3735 Examples are in the directory MetisExamples.  WARNING: the
  3736 Isabelle/HOL-Metis integration does not yet work properly with
  3737 multi-threading.
  3738   
  3739 * Command 'sledgehammer' invokes external automatic theorem provers as
  3740 background processes.  It generates calls to the "metis" method if
  3741 successful. These can be pasted into the proof.  Users do not have to
  3742 wait for the automatic provers to return.  WARNING: does not really
  3743 work with multi-threading.
  3744 
  3745 * New "auto_quickcheck" feature tests outermost goal statements for
  3746 potential counter-examples.  Controlled by ML references
  3747 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3748 5000 milliseconds).  Fails silently if statements is outside of
  3749 executable fragment, or any other codgenerator problem occurs.
  3750 
  3751 * New constant "undefined" with axiom "undefined x = undefined".
  3752 
  3753 * Added class "HOL.eq", allowing for code generation with polymorphic
  3754 equality.
  3755 
  3756 * Some renaming of class constants due to canonical name prefixing in
  3757 the new 'class' package:
  3758 
  3759     HOL.abs ~> HOL.abs_class.abs
  3760     HOL.divide ~> HOL.divide_class.divide
  3761     0 ~> HOL.zero_class.zero
  3762     1 ~> HOL.one_class.one
  3763     op + ~> HOL.plus_class.plus
  3764     op - ~> HOL.minus_class.minus
  3765     uminus ~> HOL.minus_class.uminus
  3766     op * ~> HOL.times_class.times
  3767     op < ~> HOL.ord_class.less
  3768     op <= > HOL.ord_class.less_eq
  3769     Nat.power ~> Power.power_class.power
  3770     Nat.size ~> Nat.size_class.size
  3771     Numeral.number_of ~> Numeral.number_class.number_of
  3772     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3773     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3774     Orderings.min ~> Orderings.ord_class.min
  3775     Orderings.max ~> Orderings.ord_class.max
  3776     Divides.op div ~> Divides.div_class.div
  3777     Divides.op mod ~> Divides.div_class.mod
  3778     Divides.op dvd ~> Divides.div_class.dvd
  3779 
  3780 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3781 
  3782 a) User-defined constants using any of the names "plus", "minus",
  3783 "times", "less" or "less_eq". The standard syntax translations for
  3784 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3785 names.
  3786 
  3787 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3788 INCOMPATIBILITY: use more specific names.
  3789 
  3790 c) Permutative equations (e.g. "a + b = b + a")
  3791 Since the change of names also changes the order of terms, permutative
  3792 rewrite rules may get applied in a different order. Experience shows
  3793 that this is rarely the case (only two adaptions in the whole Isabelle
  3794 distribution).  INCOMPATIBILITY: rewrite proofs
  3795 
  3796 d) ML code directly refering to constant names
  3797 This in general only affects hand-written proof tactics, simprocs and
  3798 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3799 Consider using @{const_name} antiquotation.
  3800 
  3801 * New class "default" with associated constant "default".
  3802 
  3803 * Function "sgn" is now overloaded and available on int, real, complex
  3804 (and other numeric types), using class "sgn".  Two possible defs of
  3805 sgn are given as equational assumptions in the classes sgn_if and
  3806 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3807 INCOMPATIBILITY.
  3808 
  3809 * Locale "partial_order" now unified with class "order" (cf. theory
  3810 Orderings), added parameter "less".  INCOMPATIBILITY.
  3811 
  3812 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3813 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3814 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3815 
  3816 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3817 changed order of proof goals in instance proofs.
  3818 
  3819 * The transitivity reasoner for partial and linear orders is set up
  3820 for classes "order" and "linorder".  Instances of the reasoner are available
  3821 in all contexts importing or interpreting the corresponding locales.
  3822 Method "order" invokes the reasoner separately; the reasoner
  3823 is also integrated with the Simplifier as a solver.  Diagnostic
  3824 command 'print_orders' shows the available instances of the reasoner
  3825 in the current context.
  3826 
  3827 * Localized monotonicity predicate in theory "Orderings"; integrated
  3828 lemmas max_of_mono and min_of_mono with this predicate.
  3829 INCOMPATIBILITY.
  3830 
  3831 * Formulation of theorem "dense" changed slightly due to integration
  3832 with new class dense_linear_order.
  3833 
  3834 * Uniform lattice theory development in HOL.
  3835 
  3836     constants "meet" and "join" now named "inf" and "sup"
  3837     constant "Meet" now named "Inf"
  3838 
  3839     classes "meet_semilorder" and "join_semilorder" now named
  3840       "lower_semilattice" and "upper_semilattice"
  3841     class "lorder" now named "lattice"
  3842     class "comp_lat" now named "complete_lattice"
  3843 
  3844     Instantiation of lattice classes allows explicit definitions
  3845     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3846 
  3847   INCOMPATIBILITY.  Theorem renames:
  3848 
  3849     meet_left_le            ~> inf_le1
  3850     meet_right_le           ~> inf_le2
  3851     join_left_le            ~> sup_ge1
  3852     join_right_le           ~> sup_ge2
  3853     meet_join_le            ~> inf_sup_ord
  3854     le_meetI                ~> le_infI
  3855     join_leI                ~> le_supI
  3856     le_meet                 ~> le_inf_iff
  3857     le_join                 ~> ge_sup_conv
  3858     meet_idempotent         ~> inf_idem
  3859     join_idempotent         ~> sup_idem
  3860     meet_comm               ~> inf_commute
  3861     join_comm               ~> sup_commute
  3862     meet_leI1               ~> le_infI1
  3863     meet_leI2               ~> le_infI2
  3864     le_joinI1               ~> le_supI1
  3865     le_joinI2               ~> le_supI2
  3866     meet_assoc              ~> inf_assoc
  3867     join_assoc              ~> sup_assoc
  3868     meet_left_comm          ~> inf_left_commute
  3869     meet_left_idempotent    ~> inf_left_idem
  3870     join_left_comm          ~> sup_left_commute
  3871     join_left_idempotent    ~> sup_left_idem
  3872     meet_aci                ~> inf_aci
  3873     join_aci                ~> sup_aci
  3874     le_def_meet             ~> le_iff_inf
  3875     le_def_join             ~> le_iff_sup
  3876     join_absorp2            ~> sup_absorb2
  3877     join_absorp1            ~> sup_absorb1
  3878     meet_absorp1            ~> inf_absorb1
  3879     meet_absorp2            ~> inf_absorb2
  3880     meet_join_absorp        ~> inf_sup_absorb
  3881     join_meet_absorp        ~> sup_inf_absorb
  3882     distrib_join_le         ~> distrib_sup_le
  3883     distrib_meet_le         ~> distrib_inf_le
  3884 
  3885     add_meet_distrib_left   ~> add_inf_distrib_left
  3886     add_join_distrib_left   ~> add_sup_distrib_left
  3887     is_join_neg_meet        ~> is_join_neg_inf
  3888     is_meet_neg_join        ~> is_meet_neg_sup
  3889     add_meet_distrib_right  ~> add_inf_distrib_right
  3890     add_join_distrib_right  ~> add_sup_distrib_right
  3891     add_meet_join_distribs  ~> add_sup_inf_distribs
  3892     join_eq_neg_meet        ~> sup_eq_neg_inf
  3893     meet_eq_neg_join        ~> inf_eq_neg_sup
  3894     add_eq_meet_join        ~> add_eq_inf_sup
  3895     meet_0_imp_0            ~> inf_0_imp_0
  3896     join_0_imp_0            ~> sup_0_imp_0
  3897     meet_0_eq_0             ~> inf_0_eq_0
  3898     join_0_eq_0             ~> sup_0_eq_0
  3899     neg_meet_eq_join        ~> neg_inf_eq_sup
  3900     neg_join_eq_meet        ~> neg_sup_eq_inf
  3901     join_eq_if              ~> sup_eq_if
  3902 
  3903     mono_meet               ~> mono_inf
  3904     mono_join               ~> mono_sup
  3905     meet_bool_eq            ~> inf_bool_eq
  3906     join_bool_eq            ~> sup_bool_eq
  3907     meet_fun_eq             ~> inf_fun_eq
  3908     join_fun_eq             ~> sup_fun_eq
  3909     meet_set_eq             ~> inf_set_eq
  3910     join_set_eq             ~> sup_set_eq
  3911     meet1_iff               ~> inf1_iff
  3912     meet2_iff               ~> inf2_iff
  3913     meet1I                  ~> inf1I
  3914     meet2I                  ~> inf2I
  3915     meet1D1                 ~> inf1D1
  3916     meet2D1                 ~> inf2D1
  3917     meet1D2                 ~> inf1D2
  3918     meet2D2                 ~> inf2D2
  3919     meet1E                  ~> inf1E
  3920     meet2E                  ~> inf2E
  3921     join1_iff               ~> sup1_iff
  3922     join2_iff               ~> sup2_iff
  3923     join1I1                 ~> sup1I1
  3924     join2I1                 ~> sup2I1
  3925     join1I1                 ~> sup1I1
  3926     join2I2                 ~> sup1I2
  3927     join1CI                 ~> sup1CI
  3928     join2CI                 ~> sup2CI
  3929     join1E                  ~> sup1E
  3930     join2E                  ~> sup2E
  3931 
  3932     is_meet_Meet            ~> is_meet_Inf
  3933     Meet_bool_def           ~> Inf_bool_def
  3934     Meet_fun_def            ~> Inf_fun_def
  3935     Meet_greatest           ~> Inf_greatest
  3936     Meet_lower              ~> Inf_lower
  3937     Meet_set_def            ~> Inf_set_def
  3938 
  3939     Sup_def                 ~> Sup_Inf
  3940     Sup_bool_eq             ~> Sup_bool_def
  3941     Sup_fun_eq              ~> Sup_fun_def
  3942     Sup_set_eq              ~> Sup_set_def
  3943 
  3944     listsp_meetI            ~> listsp_infI
  3945     listsp_meet_eq          ~> listsp_inf_eq
  3946 
  3947     meet_min                ~> inf_min
  3948     join_max                ~> sup_max
  3949 
  3950 * Added syntactic class "size"; overloaded constant "size" now has
  3951 type "'a::size ==> bool"
  3952 
  3953 * Internal reorganisation of `size' of datatypes: size theorems
  3954 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3955 simplification rules by default!); theorems "prod.size" now named
  3956 "*.size".
  3957 
  3958 * Class "div" now inherits from class "times" rather than "type".
  3959 INCOMPATIBILITY.
  3960 
  3961 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  3962 Linorder etc.  have disappeared; operations defined in terms of
  3963 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  3964 
  3965 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  3966 
  3967 * HOL-Word: New extensive library and type for generic, fixed size
  3968 machine words, with arithemtic, bit-wise, shifting and rotating
  3969 operations, reflection into int, nat, and bool lists, automation for
  3970 linear arithmetic (by automatic reflection into nat or int), including
  3971 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  3972 arithmetic type classes, supporting automatic simplification of
  3973 numerals on all operations.
  3974 
  3975 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  3976 
  3977 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  3978 
  3979 * Code generator library theories:
  3980   - Code_Integer represents HOL integers by big integer literals in target
  3981     languages.
  3982   - Code_Char represents HOL characters by character literals in target
  3983     languages.
  3984   - Code_Char_chr like Code_Char, but also offers treatment of character
  3985     codes; includes Code_Integer.
  3986   - Executable_Set allows to generate code for finite sets using lists.
  3987   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  3988     denominator).
  3989   - Executable_Real implements a subset of real numbers, namly those
  3990     representable by rational numbers.
  3991   - Efficient_Nat implements natural numbers by integers, which in general will
  3992     result in higher efficency; pattern matching with 0/Suc is eliminated;
  3993     includes Code_Integer.
  3994   - Code_Index provides an additional datatype index which is mapped to
  3995     target-language built-in integers.
  3996   - Code_Message provides an additional datatype message_string which is isomorphic to
  3997     strings; messages are mapped to target-language strings.
  3998 
  3999 * New package for inductive predicates
  4000 
  4001   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  4002 
  4003     inductive
  4004       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4005       for z_1 :: U_1 and ... and z_n :: U_m
  4006     where
  4007       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4008     | ...
  4009 
  4010   with full support for type-inference, rather than
  4011 
  4012     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4013 
  4014     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4015     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4016 
  4017     inductive "s z_1 ... z_m"
  4018     intros
  4019       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4020       ...
  4021 
  4022   For backward compatibility, there is a wrapper allowing inductive
  4023   sets to be defined with the new package via
  4024 
  4025     inductive_set
  4026       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4027       for z_1 :: U_1 and ... and z_n :: U_m
  4028     where
  4029       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4030     | ...
  4031 
  4032   or
  4033 
  4034     inductive_set
  4035       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4036       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4037       for z_1 :: U_1 and ... and z_n :: U_m
  4038     where
  4039       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4040     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4041     | ...
  4042 
  4043   if the additional syntax "p ..." is required.
  4044 
  4045   Numerous examples can be found in the subdirectories src/HOL/Auth,
  4046   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  4047 
  4048   INCOMPATIBILITIES:
  4049 
  4050   - Since declaration and definition of inductive sets or predicates
  4051     is no longer separated, abbreviations involving the newly
  4052     introduced sets or predicates must be specified together with the
  4053     introduction rules after the 'where' keyword (see above), rather
  4054     than before the actual inductive definition.
  4055 
  4056   - The variables in induction and elimination rules are now
  4057     quantified in the order of their occurrence in the introduction
  4058     rules, rather than in alphabetical order. Since this may break
  4059     some proofs, these proofs either have to be repaired, e.g. by
  4060     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  4061     statements of the form
  4062 
  4063       case (rule_i a_i_1 ... a_i_{k_i})
  4064 
  4065     or the old order of quantification has to be restored by explicitly adding
  4066     meta-level quantifiers in the introduction rules, i.e.
  4067 
  4068       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  4069 
  4070   - The format of the elimination rules is now
  4071 
  4072       p z_1 ... z_m x_1 ... x_n ==>
  4073         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4074         ==> ... ==> P
  4075 
  4076     for predicates and
  4077 
  4078       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4079         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4080         ==> ... ==> P
  4081 
  4082     for sets rather than
  4083 
  4084       x : s z_1 ... z_m ==>
  4085         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4086         ==> ... ==> P
  4087 
  4088     This may require terms in goals to be expanded to n-tuples
  4089     (e.g. using case_tac or simplification with the split_paired_all
  4090     rule) before the above elimination rule is applicable.
  4091 
  4092   - The elimination or case analysis rules for (mutually) inductive
  4093     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4094     list of rules "p_1_..._p_k.elims" is no longer available.
  4095 
  4096 * New package "function"/"fun" for general recursive functions,
  4097 supporting mutual and nested recursion, definitions in local contexts,
  4098 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4099 for small examples, and the separate tutorial on the function
  4100 package. The old recdef "package" is still available as before, but
  4101 users are encouraged to use the new package.
  4102 
  4103 * Method "lexicographic_order" automatically synthesizes termination
  4104 relations as lexicographic combinations of size measures. 
  4105 
  4106 * Case-expressions allow arbitrary constructor-patterns (including
  4107 "_") and take their order into account, like in functional
  4108 programming.  Internally, this is translated into nested
  4109 case-expressions; missing cases are added and mapped to the predefined
  4110 constant "undefined". In complicated cases printing may no longer show
  4111 the original input but the internal form. Lambda-abstractions allow
  4112 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4113 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4114 variable.
  4115 
  4116 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4117 is an abbreviation for "of_nat :: nat => int". The simplification
  4118 rules for "of_nat" have been changed to work like "int" did
  4119 previously.  Potential INCOMPATIBILITY:
  4120   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4121   - of_nat_diff and of_nat_mult are no longer default simp rules
  4122 
  4123 * Method "algebra" solves polynomial equations over (semi)rings using
  4124 Groebner bases. The (semi)ring structure is defined by locales and the
  4125 tool setup depends on that generic context. Installing the method for
  4126 a specific type involves instantiating the locale and possibly adding
  4127 declarations for computation on the coefficients.  The method is
  4128 already instantiated for natural numbers and for the axiomatic class
  4129 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4130 CALCULEMUS 2007 for the general principles underlying this
  4131 architecture of context-aware proof-tools.
  4132 
  4133 * Method "ferrack" implements quantifier elimination over
  4134 special-purpose dense linear orders using locales (analogous to
  4135 "algebra"). The method is already installed for class
  4136 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4137 rat, etc.
  4138 
  4139 * Former constant "List.op @" now named "List.append".  Use ML
  4140 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4141 circumvent possible incompatibilities when working on ML level.
  4142 
  4143 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4144 
  4145 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4146 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4147 
  4148 * New syntax for Haskell-like list comprehension (input only), eg.
  4149 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4150 
  4151 * The special syntax for function "filter" has changed from [x :
  4152 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4153 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4154 
  4155 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4156 defined on nat only, as an abbreviation for [a..<Suc b]
  4157 INCOMPATIBILITY.
  4158 
  4159 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4160 
  4161 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4162 
  4163 * New lemma collection field_simps (an extension of ring_simps) for
  4164 manipulating (in)equations involving division. Multiplies with all
  4165 denominators that can be proved to be non-zero (in equations) or
  4166 positive/negative (in inequations).
  4167 
  4168 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4169 have been improved and renamed to ring_simps, group_simps and
  4170 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4171 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4172 
  4173 * Theory Library/Commutative_Ring: switched from recdef to function
  4174 package; constants add, mul, pow now curried.  Infix syntax for
  4175 algebraic operations.
  4176 
  4177 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4178 INCOMPATIBILITY.
  4179 
  4180 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4181 INCOMPATIBILITY.
  4182 
  4183 * HOL/records: generalised field-update to take a function on the
  4184 field rather than the new value: r(|A := x|) is translated to A_update
  4185 (K x) r The K-combinator that is internally used is called K_record.
  4186 INCOMPATIBILITY: Usage of the plain update functions has to be
  4187 adapted.
  4188  
  4189 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4190 * x = 0, which are required for a semiring.  Richer structures do not
  4191 inherit from semiring_0 anymore, because this property is a theorem
  4192 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4193 there is more to prove, but this is mostly trivial.
  4194 
  4195 * Class "recpower" is generalized to arbitrary monoids, not just
  4196 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4197 commutativity or semiring properties additionally.
  4198 
  4199 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4200 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4201 better use 'abbreviation'.
  4202 
  4203 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4204 
  4205 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4206 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4207 significant changes for setting up numeral syntax for types:
  4208   - New constants Numeral.pred and Numeral.succ instead
  4209       of former Numeral.bin_pred and Numeral.bin_succ.
  4210   - Use integer operations instead of bin_add, bin_mult and so on.
  4211   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4212   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4213 
  4214 See src/HOL/Integ/IntArith.thy for an example setup.
  4215 
  4216 * Command 'normal_form' computes the normal form of a term that may
  4217 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4218 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4219 heavy-duty computations because the functions are compiled to ML
  4220 first.  Correspondingly, a method "normalization" is provided.  See
  4221 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4222 
  4223 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4224 25 like -->); output depends on the "iff" print_mode, the default is
  4225 "A = B" (with priority 50).
  4226 
  4227 * Relations less (<) and less_eq (<=) are also available on type bool.
  4228 Modified syntax to disallow nesting without explicit parentheses,
  4229 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4230 INCOMPATIBILITY.
  4231 
  4232 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4233 
  4234 * Relation composition operator "op O" now has precedence 75 and binds
  4235 stronger than union and intersection. INCOMPATIBILITY.
  4236 
  4237 * The old set interval syntax "{m..n(}" (and relatives) has been
  4238 removed.  Use "{m..<n}" (and relatives) instead.
  4239 
  4240 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4241 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4242 ``declare [[simproc del: neq]]''.
  4243 
  4244 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4245 True/False.
  4246 
  4247 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4248 
  4249 * Theorem setsum_mult renamed to setsum_right_distrib.
  4250 
  4251 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4252 ``rule'' method.
  4253 
  4254 * Reimplemented methods "sat" and "satx", with several improvements:
  4255 goals no longer need to be stated as "<prems> ==> False", equivalences
  4256 (i.e. "=" on type bool) are handled, variable names of the form
  4257 "lit_<n>" are no longer reserved, significant speedup.
  4258 
  4259 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4260 zChaff is still supported as well.
  4261 
  4262 * 'inductive' and 'datatype': provide projections of mutual rules,
  4263 bundled as foo_bar.inducts;
  4264 
  4265 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4266 Library.
  4267 
  4268 * Library: moved theory Accessible_Part to main HOL.
  4269 
  4270 * Library: added theory Coinductive_List of potentially infinite lists
  4271 as greatest fixed-point.
  4272 
  4273 * Library: added theory AssocList which implements (finite) maps as
  4274 association lists.
  4275 
  4276 * Method "evaluation" solves goals (i.e. a boolean expression)
  4277 efficiently by compiling it to ML.  The goal is "proved" (via an
  4278 oracle) if it evaluates to True.
  4279 
  4280 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4281 also when invoked by the simplifier.  This results in the Simplifier
  4282 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4283 Configuration option fast_arith_split_limit=0 recovers the old
  4284 behavior.
  4285 
  4286 * Support for hex (0x20) and binary (0b1001) numerals.
  4287 
  4288 * New method: reify eqs (t), where eqs are equations for an
  4289 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4290 parameter, computes a term s::'b and a list xs::'a list and proves the
  4291 theorem I xs s = t. This is also known as reification or quoting. The
  4292 resulting theorem is applied to the subgoal to substitute t with I xs
  4293 s.  If t is omitted, the subgoal itself is reified.
  4294 
  4295 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4296 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4297 where f is supposed to be a computable function (in the sense of code
  4298 generattion). The method uses reify to compute s and xs as above then
  4299 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4300 r and finally gets the theorem t = r, which is again applied to the
  4301 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4302 
  4303 * Reflection: Automatic reification now handels binding, an example is
  4304 available in src/HOL/ex/ReflectionEx.thy
  4305 
  4306 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4307 command 'statespace' that is similar to 'record', but introduces an
  4308 abstract specification based on the locale infrastructure instead of
  4309 HOL types.  This leads to extra flexibility in composing state spaces,
  4310 in particular multiple inheritance and renaming of components.
  4311 
  4312 
  4313 *** HOL-Complex ***
  4314 
  4315 * Hyperreal: Functions root and sqrt are now defined on negative real
  4316 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4317 Nonnegativity side conditions have been removed from many lemmas, so
  4318 that more subgoals may now be solved by simplification; potential
  4319 INCOMPATIBILITY.
  4320 
  4321 * Real: new type classes formalize real normed vector spaces and
  4322 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4323 and norm :: 'a => real.
  4324 
  4325 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4326 reals into other types. The overloaded constant Reals :: 'a set is now
  4327 defined as range of_real; potential INCOMPATIBILITY.
  4328 
  4329 * Real: proper support for ML code generation, including 'quickcheck'.
  4330 Reals are implemented as arbitrary precision rationals.
  4331 
  4332 * Hyperreal: Several constants that previously worked only for the
  4333 reals have been generalized, so they now work over arbitrary vector
  4334 spaces. Type annotations may need to be added in some cases; potential
  4335 INCOMPATIBILITY.
  4336 
  4337   Infinitesimal  :: ('a::real_normed_vector) star set
  4338   HFinite        :: ('a::real_normed_vector) star set
  4339   HInfinite      :: ('a::real_normed_vector) star set
  4340   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4341   monad          :: ('a::real_normed_vector) star => 'a star set
  4342   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4343   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4344   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4345   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4346   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4347   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4348   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4349   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4350   sgn            :: 'a::real_normed_vector => 'a
  4351   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4352 
  4353 * Complex: Some complex-specific constants are now abbreviations for
  4354 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4355 hnorm.  Other constants have been entirely removed in favor of the
  4356 polymorphic versions (INCOMPATIBILITY):
  4357 
  4358   approx        <-- capprox
  4359   HFinite       <-- CFinite
  4360   HInfinite     <-- CInfinite
  4361   Infinitesimal <-- CInfinitesimal
  4362   monad         <-- cmonad
  4363   galaxy        <-- cgalaxy
  4364   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4365   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4366   (ns)deriv     <-- (ns)cderiv
  4367 
  4368 
  4369 *** HOL-Algebra ***
  4370 
  4371 * Formalisation of ideals and the quotient construction over rings.
  4372 
  4373 * Order and lattice theory no longer based on records.
  4374 INCOMPATIBILITY.
  4375 
  4376 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4377 greatest_closed.  INCOMPATIBILITY.
  4378 
  4379 * Method algebra is now set up via an attribute.  For examples see
  4380 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4381 of algebraic structures.
  4382 
  4383 * Renamed theory CRing to Ring.
  4384 
  4385 
  4386 *** HOL-Nominal ***
  4387 
  4388 * Substantial, yet incomplete support for nominal datatypes (binding
  4389 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4390 src/HOL/Nominal/Examples.  Prospective users should consult
  4391 http://isabelle.in.tum.de/nominal/
  4392 
  4393 
  4394 *** ML ***
  4395 
  4396 * ML basics: just one true type int, which coincides with IntInf.int
  4397 (even on SML/NJ).
  4398 
  4399 * ML within Isar: antiquotations allow to embed statically-checked
  4400 formal entities in the source, referring to the context available at
  4401 compile-time.  For example:
  4402 
  4403 ML {* @{sort "{zero,one}"} *}
  4404 ML {* @{typ "'a => 'b"} *}
  4405 ML {* @{term "%x. x"} *}
  4406 ML {* @{prop "x == y"} *}
  4407 ML {* @{ctyp "'a => 'b"} *}
  4408 ML {* @{cterm "%x. x"} *}
  4409 ML {* @{cprop "x == y"} *}
  4410 ML {* @{thm asm_rl} *}
  4411 ML {* @{thms asm_rl} *}
  4412 ML {* @{type_name c} *}
  4413 ML {* @{type_syntax c} *}
  4414 ML {* @{const_name c} *}
  4415 ML {* @{const_syntax c} *}
  4416 ML {* @{context} *}
  4417 ML {* @{theory} *}
  4418 ML {* @{theory Pure} *}
  4419 ML {* @{theory_ref} *}
  4420 ML {* @{theory_ref Pure} *}
  4421 ML {* @{simpset} *}
  4422 ML {* @{claset} *}
  4423 ML {* @{clasimpset} *}
  4424 
  4425 The same works for sources being ``used'' within an Isar context.
  4426 
  4427 * ML in Isar: improved error reporting; extra verbosity with
  4428 ML_Context.trace enabled.
  4429 
  4430 * Pure/General/table.ML: the join operations now works via exceptions
  4431 DUP/SAME instead of type option. This is simpler in simple cases, and
  4432 admits slightly more efficient complex applications.
  4433 
  4434 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4435 use Context.generic instead of just theory.
  4436 
  4437 * Pure: datatype Context.generic joins theory/Proof.context and
  4438 provides some facilities for code that works in either kind of
  4439 context, notably GenericDataFun for uniform theory and proof data.
  4440 
  4441 * Pure: simplified internal attribute type, which is now always
  4442 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4443 local (Proof.context) attributes have been discontinued, while
  4444 minimizing code duplication. Thm.rule_attribute and
  4445 Thm.declaration_attribute build canonical attributes; see also structure
  4446 Context for further operations on Context.generic, notably
  4447 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4448 declarations and definitions.
  4449 
  4450 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4451 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4452 init only required for impure data. INCOMPATIBILITY: empty really need
  4453 to be empty (no dependencies on theory content!)
  4454 
  4455 * Pure/kernel: consts certification ignores sort constraints given in
  4456 signature declarations. (This information is not relevant to the
  4457 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4458 potential INCOMPATIBILITY.
  4459 
  4460 * Pure: axiomatic type classes are now purely definitional, with
  4461 explicit proofs of class axioms and super class relations performed
  4462 internally. See Pure/axclass.ML for the main internal interfaces --
  4463 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4464 AxClass.axiomatize_class/classrel/arity supersede
  4465 Sign.add_classes/classrel/arities.
  4466 
  4467 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4468 global/local versions on theory vs. Proof.context have been
  4469 discontinued; Attrib.syntax and Method.syntax have been adapted
  4470 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4471 attributes, methods, etc.
  4472 
  4473 * Pure: several functions of signature "... -> theory -> theory * ..."
  4474 have been reoriented to "... -> theory -> ... * theory" in order to
  4475 allow natural usage in combination with the ||>, ||>>, |-> and
  4476 fold_map combinators.
  4477 
  4478 * Pure: official theorem names (closed derivations) and additional
  4479 comments (tags) are now strictly separate.  Name hints -- which are
  4480 maintained as tags -- may be attached any time without affecting the
  4481 derivation.
  4482 
  4483 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4484 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4485 achieve the old behaviour.
  4486 
  4487 * Pure: the "Goal" constant is now called "prop", supporting a
  4488 slightly more general idea of ``protecting'' meta-level rule
  4489 statements.
  4490 
  4491 * Pure: Logic.(un)varify only works in a global context, which is now
  4492 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4493 Logic.legacy_(un)varify as temporary workaround.
  4494 
  4495 * Pure: structure Name provides scalable operations for generating
  4496 internal variable names, notably Name.variants etc.  This replaces
  4497 some popular functions from term.ML:
  4498 
  4499   Term.variant		->  Name.variant
  4500   Term.variantlist	->  Name.variant_list
  4501   Term.invent_names	->  Name.invent_list
  4502 
  4503 Note that low-level renaming rarely occurs in new code -- operations
  4504 from structure Variable are used instead (see below).
  4505 
  4506 * Pure: structure Variable provides fundamental operations for proper
  4507 treatment of fixed/schematic variables in a context.  For example,
  4508 Variable.import introduces fixes for schematics of given facts and
  4509 Variable.export reverses the effect (up to renaming) -- this replaces
  4510 various freeze_thaw operations.
  4511 
  4512 * Pure: structure Goal provides simple interfaces for
  4513 init/conclude/finish and tactical prove operations (replacing former
  4514 Tactic.prove).  Goal.prove is the canonical way to prove results
  4515 within a given context; Goal.prove_global is a degraded version for
  4516 theory level goals, including a global Drule.standard.  Note that
  4517 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4518 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4519 in a locale context).
  4520 
  4521 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4522 and type checking (Syntax.check_term etc.), with common combinations
  4523 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4524 which are considered legacy and await removal.
  4525 
  4526 * Pure/Syntax: generic interfaces for type unchecking
  4527 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4528 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4529 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4530 available for convenience, but refer to the very same operations using
  4531 a mere theory instead of a full context.
  4532 
  4533 * Isar: simplified treatment of user-level errors, using exception
  4534 ERROR of string uniformly.  Function error now merely raises ERROR,
  4535 without any side effect on output channels.  The Isar toplevel takes
  4536 care of proper display of ERROR exceptions.  ML code may use plain
  4537 handle/can/try; cat_error may be used to concatenate errors like this:
  4538 
  4539   ... handle ERROR msg => cat_error msg "..."
  4540 
  4541 Toplevel ML code (run directly or through the Isar toplevel) may be
  4542 embedded into the Isar toplevel with exception display/debug like
  4543 this:
  4544 
  4545   Isar.toplevel (fn () => ...)
  4546 
  4547 INCOMPATIBILITY, removed special transform_error facilities, removed
  4548 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4549 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4550 -- use plain ERROR instead.
  4551 
  4552 * Isar: theory setup now has type (theory -> theory), instead of a
  4553 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4554 
  4555 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4556 ProofContext.debug/verbose flags.
  4557 
  4558 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4559 theory before entering a proof state.  Transactions now always see a
  4560 quasi-functional intermediate checkpoint, both in interactive and
  4561 batch mode.
  4562 
  4563 * Isar: simplified interfaces for outer syntax.  Renamed
  4564 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4565 OuterSyntax.add_parsers -- this functionality is now included in
  4566 OuterSyntax.command etc.  INCOMPATIBILITY.
  4567 
  4568 * Simplifier: the simpset of a running simplification process now
  4569 contains a proof context (cf. Simplifier.the_context), which is the
  4570 very context that the initial simpset has been retrieved from (by
  4571 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4572 (solver, looper etc.) may depend on arbitrary proof data.
  4573 
  4574 * Simplifier.inherit_context inherits the proof context (plus the
  4575 local bounds) of the current simplification process; any simproc
  4576 etc. that calls the Simplifier recursively should do this!  Removed
  4577 former Simplifier.inherit_bounds, which is already included here --
  4578 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4579 specify an explicit context using Simplifier.context/theory_context.
  4580 
  4581 * Simplifier/Classical Reasoner: more abstract interfaces
  4582 change_simpset/claset for modifying the simpset/claset reference of a
  4583 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4584 INCOMPATIBILITY.
  4585 
  4586 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4587 "Trueprop" etc.
  4588 
  4589 
  4590 *** System ***
  4591 
  4592 * settings: the default heap location within ISABELLE_HOME_USER now
  4593 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4594 Isabelle installations.
  4595 
  4596 * isabelle-process: option -S (secure mode) disables some critical
  4597 operations, notably runtime compilation and evaluation of ML source
  4598 code.
  4599 
  4600 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4601 
  4602 * Support for parallel execution, using native multicore support of
  4603 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4604 independent theories, according to the given theory header
  4605 specifications. The maximum number of worker threads is specified via
  4606 usedir option -M or the "max-threads" setting in Proof General. A
  4607 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4608 to 6 on a 8-core machine.  User-code needs to observe certain
  4609 guidelines for thread-safe programming, see appendix A in the Isar
  4610 Implementation manual.
  4611 
  4612 
  4613 
  4614 New in Isabelle2005 (October 2005)
  4615 ----------------------------------
  4616 
  4617 *** General ***
  4618 
  4619 * Theory headers: the new header syntax for Isar theories is
  4620 
  4621   theory <name>
  4622   imports <theory1> ... <theoryN>
  4623   uses <file1> ... <fileM>
  4624   begin
  4625 
  4626 where the 'uses' part is optional.  The previous syntax
  4627 
  4628   theory <name> = <theory1> + ... + <theoryN>:
  4629 
  4630 will disappear in the next release.  Use isatool fixheaders to convert
  4631 existing theory files.  Note that there is no change in ancient
  4632 non-Isar theories now, but these will disappear soon.
  4633 
  4634 * Theory loader: parent theories can now also be referred to via
  4635 relative and absolute paths.
  4636 
  4637 * Command 'find_theorems' searches for a list of criteria instead of a
  4638 list of constants. Known criteria are: intro, elim, dest, name:string,
  4639 simp:term, and any term. Criteria can be preceded by '-' to select
  4640 theorems that do not match. Intro, elim, dest select theorems that
  4641 match the current goal, name:s selects theorems whose fully qualified
  4642 name contain s, and simp:term selects all simplification rules whose
  4643 lhs match term.  Any other term is interpreted as pattern and selects
  4644 all theorems matching the pattern. Available in ProofGeneral under
  4645 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4646 
  4647   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4648 
  4649 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4650 matching the current goal as introduction rule and not having "HOL."
  4651 in their name (i.e. not being defined in theory HOL).
  4652 
  4653 * Command 'thms_containing' has been discontinued in favour of
  4654 'find_theorems'; INCOMPATIBILITY.
  4655 
  4656 * Communication with Proof General is now 8bit clean, which means that
  4657 Unicode text in UTF-8 encoding may be used within theory texts (both
  4658 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4659 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4660 
  4661   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4662   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4663 
  4664 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4665 Classical Reasoner.  Typical big applications run around 2 times
  4666 faster.
  4667 
  4668 
  4669 *** Document preparation ***
  4670 
  4671 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4672 of raw sources.  Only those symbols that do not require additional
  4673 LaTeX packages (depending on comments in isabellesym.sty) are
  4674 displayed properly, everything else is left verbatim.  isatool display
  4675 and isatool print are used as front ends (these are subject to the
  4676 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4677 
  4678 * Command tags control specific markup of certain regions of text,
  4679 notably folding and hiding.  Predefined tags include "theory" (for
  4680 theory begin and end), "proof" for proof commands, and "ML" for
  4681 commands involving ML code; the additional tags "visible" and
  4682 "invisible" are unused by default.  Users may give explicit tag
  4683 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4684 interpretation of tags is determined by the LaTeX job during document
  4685 preparation: see option -V of isatool usedir, or options -n and -t of
  4686 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4687 \isadroptag.
  4688 
  4689 Several document versions may be produced at the same time via isatool
  4690 usedir (the generated index.html will link all of them).  Typical
  4691 specifications include ''-V document=theory,proof,ML'' to present
  4692 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4693 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4694 these parts without any formal replacement text.  The Isabelle site
  4695 default settings produce ''document'' and ''outline'' versions as
  4696 specified above.
  4697 
  4698 * Several new antiquotations:
  4699 
  4700   @{term_type term} prints a term with its type annotated;
  4701 
  4702   @{typeof term} prints the type of a term;
  4703 
  4704   @{const const} is the same as @{term const}, but checks that the
  4705   argument is a known logical constant;
  4706 
  4707   @{term_style style term} and @{thm_style style thm} print a term or
  4708   theorem applying a "style" to it
  4709 
  4710   @{ML text}
  4711 
  4712 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4713 definitions, equations, inequations etc., 'concl' printing only the
  4714 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4715 to print the specified premise.  TermStyle.add_style provides an ML
  4716 interface for introducing further styles.  See also the "LaTeX Sugar"
  4717 document practical applications.  The ML antiquotation prints
  4718 type-checked ML expressions verbatim.
  4719 
  4720 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4721 and 'text' support optional locale specification '(in loc)', which
  4722 specifies the default context for interpreting antiquotations.  For
  4723 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4724 
  4725 * Option 'locale=NAME' of antiquotations specifies an alternative
  4726 context interpreting the subsequent argument.  For example: @{thm
  4727 [locale=lattice] inf_assoc}.
  4728 
  4729 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4730 a proof context.
  4731 
  4732 * Proper output of antiquotations for theory commands involving a
  4733 proof context (such as 'locale' or 'theorem (in loc) ...').
  4734 
  4735 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4736 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4737 
  4738 * isatool usedir: new option -C (default true) controls whether option
  4739 -D should include a copy of the original document directory; -C false
  4740 prevents unwanted effects such as copying of administrative CVS data.
  4741 
  4742 
  4743 *** Pure ***
  4744 
  4745 * Considerably improved version of 'constdefs' command.  Now performs
  4746 automatic type-inference of declared constants; additional support for
  4747 local structure declarations (cf. locales and HOL records), see also
  4748 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4749 sequential dependencies of definitions within a single 'constdefs'
  4750 section; moreover, the declared name needs to be an identifier.  If
  4751 all fails, consider to fall back on 'consts' and 'defs' separately.
  4752 
  4753 * Improved indexed syntax and implicit structures.  First of all,
  4754 indexed syntax provides a notational device for subscripted
  4755 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4756 expressions.  Secondly, in a local context with structure
  4757 declarations, number indexes \<^sub>n or the empty index (default
  4758 number 1) refer to a certain fixed variable implicitly; option
  4759 show_structs controls printing of implicit structures.  Typical
  4760 applications of these concepts involve record types and locales.
  4761 
  4762 * New command 'no_syntax' removes grammar declarations (and
  4763 translations) resulting from the given syntax specification, which is
  4764 interpreted in the same manner as for the 'syntax' command.
  4765 
  4766 * 'Advanced' translation functions (parse_translation etc.) may depend
  4767 on the signature of the theory context being presently used for
  4768 parsing/printing, see also isar-ref manual.
  4769 
  4770 * Improved 'oracle' command provides a type-safe interface to turn an
  4771 ML expression of type theory -> T -> term into a primitive rule of
  4772 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4773 is already included here); see also FOL/ex/IffExample.thy;
  4774 INCOMPATIBILITY.
  4775 
  4776 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4777 before); "cI" is no longer bound, use "c.intro" instead.
  4778 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4779 axclasses vs. locales.
  4780 
  4781 * Improved internal renaming of symbolic identifiers -- attach primes
  4782 instead of base 26 numbers.
  4783 
  4784 * New flag show_question_marks controls printing of leading question
  4785 marks in schematic variable names.
  4786 
  4787 * In schematic variable names, *any* symbol following \<^isub> or
  4788 \<^isup> is now treated as part of the base name.  For example, the
  4789 following works without printing of awkward ".0" indexes:
  4790 
  4791   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4792     by simp
  4793 
  4794 * Inner syntax includes (*(*nested*) comments*).
  4795 
  4796 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4797 annotations as "(00...)".
  4798 
  4799 * Clear separation of logical types and nonterminals, where the latter
  4800 may only occur in 'syntax' specifications or type abbreviations.
  4801 Before that distinction was only partially implemented via type class
  4802 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4803 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4804 exotic syntax specifications may require further adaption
  4805 (e.g. Cube/Cube.thy).
  4806 
  4807 * Removed obsolete type class "logic", use the top sort {} instead.
  4808 Note that non-logical types should be declared as 'nonterminals'
  4809 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4810 specifications.
  4811 
  4812 * Attributes 'induct' and 'cases': type or set names may now be
  4813 locally fixed variables as well.
  4814 
  4815 * Simplifier: can now control the depth to which conditional rewriting
  4816 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4817 Limit.
  4818 
  4819 * Simplifier: simplification procedures may now take the current
  4820 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4821 interface), which is very useful for calling the Simplifier
  4822 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4823 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4824 low-level mk_simproc no longer applies Logic.varify internally, to
  4825 allow for use in a context of fixed variables.
  4826 
  4827 * thin_tac now works even if the assumption being deleted contains !!
  4828 or ==>.  More generally, erule now works even if the major premise of
  4829 the elimination rule contains !! or ==>.
  4830 
  4831 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4832 
  4833 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4834 from Pure, which contains all common declarations already.  Both
  4835 theories are defined via plain Isabelle/Isar .thy files.
  4836 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4837 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4838 use isatool fixcpure to adapt your theory and ML sources.
  4839 
  4840 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4841 selections of theorems in named facts via index ranges.
  4842 
  4843 * 'print_theorems': in theory mode, really print the difference
  4844 wrt. the last state (works for interactive theory development only),
  4845 in proof mode print all local facts (cf. 'print_facts');
  4846 
  4847 * 'hide': option '(open)' hides only base names.
  4848 
  4849 * More efficient treatment of intermediate checkpoints in interactive
  4850 theory development.
  4851 
  4852 * Code generator is now invoked via code_module (incremental code
  4853 generation) and code_library (modular code generation, ML structures
  4854 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4855 must be quoted when used as identifiers.
  4856 
  4857 * New 'value' command for reading, evaluating and printing terms using
  4858 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4859 quoted when used as identifier.
  4860 
  4861 
  4862 *** Locales ***
  4863 
  4864 * New commands for the interpretation of locale expressions in
  4865 theories (1), locales (2) and proof contexts (3).  These generate
  4866 proof obligations from the expression specification.  After the
  4867 obligations have been discharged, theorems of the expression are added
  4868 to the theory, target locale or proof context.  The synopsis of the
  4869 commands is a follows:
  4870 
  4871   (1) interpretation expr inst
  4872   (2) interpretation target < expr
  4873   (3) interpret expr inst
  4874 
  4875 Interpretation in theories and proof contexts require a parameter
  4876 instantiation of terms from the current context.  This is applied to
  4877 specifications and theorems of the interpreted expression.
  4878 Interpretation in locales only permits parameter renaming through the
  4879 locale expression.  Interpretation is smart in that interpretations
  4880 that are active already do not occur in proof obligations, neither are
  4881 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4882 inspect active interpretations of a particular locale.  For details,
  4883 see the Isar Reference manual.  Examples can be found in
  4884 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4885 
  4886 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4887 'interpret' instead.
  4888 
  4889 * New context element 'constrains' for adding type constraints to
  4890 parameters.
  4891 
  4892 * Context expressions: renaming of parameters with syntax
  4893 redeclaration.
  4894 
  4895 * Locale declaration: 'includes' disallowed.
  4896 
  4897 * Proper static binding of attribute syntax -- i.e. types / terms /
  4898 facts mentioned as arguments are always those of the locale definition
  4899 context, independently of the context of later invocations.  Moreover,
  4900 locale operations (renaming and type / term instantiation) are applied
  4901 to attribute arguments as expected.
  4902 
  4903 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4904 actual attributes; rare situations may require Attrib.attribute to
  4905 embed those attributes into Attrib.src that lack concrete syntax.
  4906 Attribute implementations need to cooperate properly with the static
  4907 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4908 Attrib.XXX_thm etc. already do the right thing without further
  4909 intervention.  Only unusual applications -- such as "where" or "of"
  4910 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4911 on the context and the facts involved -- may have to assign parsed
  4912 values to argument tokens explicitly.
  4913 
  4914 * Changed parameter management in theorem generation for long goal
  4915 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4916 theorem statement in rare situations.
  4917 
  4918 * Locale inspection command 'print_locale' omits notes elements.  Use
  4919 'print_locale!' to have them included in the output.
  4920 
  4921 
  4922 *** Provers ***
  4923 
  4924 * Provers/hypsubst.ML: improved version of the subst method, for
  4925 single-step rewriting: it now works in bound variable contexts. New is
  4926 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4927 rewrite a different subterm than the original subst method, which is
  4928 still available as 'simplesubst'.
  4929 
  4930 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4931 and quasi orders.
  4932 
  4933 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4934 reflexive-transitive closure of relations.
  4935 
  4936 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4937 limit (previously hard-coded with a value of 20) user-definable.
  4938 
  4939 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4940 is peformed already.  Object-logics merely need to finish their
  4941 initial simpset configuration as before.  INCOMPATIBILITY.
  4942 
  4943 
  4944 *** HOL ***
  4945 
  4946 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4947 
  4948   syntax (epsilon)
  4949     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4950 
  4951 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4952 and x-symbol; use option '-m epsilon' to get it actually printed.
  4953 Moreover, the mathematically important symbolic identifier \<epsilon>
  4954 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4955 
  4956 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  4957 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  4958 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  4959 support corresponding Isar calculations.
  4960 
  4961 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  4962 instead of ":".
  4963 
  4964 * theory SetInterval: changed the syntax for open intervals:
  4965 
  4966   Old       New
  4967   {..n(}    {..<n}
  4968   {)n..}    {n<..}
  4969   {m..n(}   {m..<n}
  4970   {)m..n}   {m<..n}
  4971   {)m..n(}  {m<..<n}
  4972 
  4973 The old syntax is still supported but will disappear in the next
  4974 release.  For conversion use the following Emacs search and replace
  4975 patterns (these are not perfect but work quite well):
  4976 
  4977   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  4978   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  4979 
  4980 * Theory Commutative_Ring (in Library): method comm_ring for proving
  4981 equalities in commutative rings; method 'algebra' provides a generic
  4982 interface.
  4983 
  4984 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  4985 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  4986 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  4987 be a tuple pattern.
  4988 
  4989 Some new syntax forms are available:
  4990 
  4991   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  4992   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  4993   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  4994   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  4995 
  4996 The latter form "\<Sum>x < k. e" used to be based on a separate
  4997 function "Summation", which has been discontinued.
  4998 
  4999 * theory Finite_Set: in structured induction proofs, the insert case
  5000 is now 'case (insert x F)' instead of the old counterintuitive 'case
  5001 (insert F x)'.
  5002 
  5003 * The 'refute' command has been extended to support a much larger
  5004 fragment of HOL, including axiomatic type classes, constdefs and
  5005 typedefs, inductive datatypes and recursion.
  5006 
  5007 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  5008 Requires zChaff with proof generation to be installed.  See
  5009 HOL/ex/SAT_Examples.thy for examples.
  5010 
  5011 * Datatype induction via method 'induct' now preserves the name of the
  5012 induction variable. For example, when proving P(xs::'a list) by
  5013 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  5014 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  5015 in unstructured proof scripts.
  5016 
  5017 * Reworked implementation of records.  Improved scalability for
  5018 records with many fields, avoiding performance problems for type
  5019 inference. Records are no longer composed of nested field types, but
  5020 of nested extension types. Therefore the record type only grows linear
  5021 in the number of extensions and not in the number of fields.  The
  5022 top-level (users) view on records is preserved.  Potential
  5023 INCOMPATIBILITY only in strange cases, where the theory depends on the
  5024 old record representation. The type generated for a record is called
  5025 <record_name>_ext_type.
  5026 
  5027 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  5028 proofs triggered by a record definition or a simproc (if
  5029 quick_and_dirty is enabled).  Definitions of large records can take
  5030 quite long.
  5031 
  5032 New simproc record_upd_simproc for simplification of multiple record
  5033 updates enabled by default.  Moreover, trivial updates are also
  5034 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  5035 occasionally, since simplification is more powerful by default.
  5036 
  5037 * typedef: proper support for polymorphic sets, which contain extra
  5038 type-variables in the term.
  5039 
  5040 * Simplifier: automatically reasons about transitivity chains
  5041 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  5042 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  5043 old proofs break occasionally as simplification may now solve more
  5044 goals than previously.
  5045 
  5046 * Simplifier: converts x <= y into x = y if assumption y <= x is
  5047 present.  Works for all partial orders (class "order"), in particular
  5048 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  5049 just like y <= x.
  5050 
  5051 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  5052 bound variable or a constant then the let is unfolded.  Otherwise
  5053 first a is simplified to b, and then f b is simplified to g. If
  5054 possible we abstract b from g arriving at "let x = b in h x",
  5055 otherwise we unfold the let and arrive at g.  The simproc can be
  5056 enabled/disabled by the reference use_let_simproc.  Potential
  5057 INCOMPATIBILITY since simplification is more powerful by default.
  5058 
  5059 * Classical reasoning: the meson method now accepts theorems as arguments.
  5060 
  5061 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  5062 jobs to provide advice on the provability of subgoals.
  5063 
  5064 * Theory OrderedGroup and Ring_and_Field: various additions and
  5065 improvements to faciliate calculations involving equalities and
  5066 inequalities.
  5067 
  5068 The following theorems have been eliminated or modified
  5069 (INCOMPATIBILITY):
  5070 
  5071   abs_eq             now named abs_of_nonneg
  5072   abs_of_ge_0        now named abs_of_nonneg
  5073   abs_minus_eq       now named abs_of_nonpos
  5074   imp_abs_id         now named abs_of_nonneg
  5075   imp_abs_neg_id     now named abs_of_nonpos
  5076   mult_pos           now named mult_pos_pos
  5077   mult_pos_le        now named mult_nonneg_nonneg
  5078   mult_pos_neg_le    now named mult_nonneg_nonpos
  5079   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5080   mult_neg           now named mult_neg_neg
  5081   mult_neg_le        now named mult_nonpos_nonpos
  5082 
  5083 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5084      
  5085      zero_le_square
  5086      not_square_less_zero 
  5087 
  5088   The following lemmas have been deleted from Real/RealPow:
  5089   
  5090      realpow_zero_zero
  5091      realpow_two
  5092      realpow_less
  5093      zero_le_power
  5094      realpow_two_le
  5095      abs_realpow_two
  5096      realpow_two_abs     
  5097 
  5098 * Theory Parity: added rules for simplifying exponents.
  5099 
  5100 * Theory List:
  5101 
  5102 The following theorems have been eliminated or modified
  5103 (INCOMPATIBILITY):
  5104 
  5105   list_all_Nil       now named list_all.simps(1)
  5106   list_all_Cons      now named list_all.simps(2)
  5107   list_all_conv      now named list_all_iff
  5108   set_mem_eq         now named mem_iff
  5109 
  5110 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5111 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5112 
  5113 
  5114 *** HOL-Complex ***
  5115 
  5116 * Theory RealDef: better support for embedding natural numbers and
  5117 integers in the reals.
  5118 
  5119 The following theorems have been eliminated or modified
  5120 (INCOMPATIBILITY):
  5121 
  5122   exp_ge_add_one_self  now requires no hypotheses
  5123   real_of_int_add      reversed direction of equality (use [symmetric])
  5124   real_of_int_minus    reversed direction of equality (use [symmetric])
  5125   real_of_int_diff     reversed direction of equality (use [symmetric])
  5126   real_of_int_mult     reversed direction of equality (use [symmetric])
  5127 
  5128 * Theory RComplete: expanded support for floor and ceiling functions.
  5129 
  5130 * Theory Ln is new, with properties of the natural logarithm
  5131 
  5132 * Hyperreal: There is a new type constructor "star" for making
  5133 nonstandard types.  The old type names are now type synonyms:
  5134 
  5135   hypreal = real star
  5136   hypnat = nat star
  5137   hcomplex = complex star
  5138 
  5139 * Hyperreal: Many groups of similarly-defined constants have been
  5140 replaced by polymorphic versions (INCOMPATIBILITY):
  5141 
  5142   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5143 
  5144   starset      <-- starsetNat, starsetC
  5145   *s*          <-- *sNat*, *sc*
  5146   starset_n    <-- starsetNat_n, starsetC_n
  5147   *sn*         <-- *sNatn*, *scn*
  5148   InternalSets <-- InternalNatSets, InternalCSets
  5149 
  5150   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5151   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5152   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5153   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5154   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5155 
  5156 * Hyperreal: Many type-specific theorems have been removed in favor of
  5157 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5158 
  5159   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5160   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5161   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5162   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5163   right_minus <-- hypreal_add_minus
  5164   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5165   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5166   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5167   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5168   mult_1_right <-- hcomplex_mult_one_right
  5169   mult_zero_left <-- hcomplex_mult_zero_left
  5170   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5171   right_distrib <-- hypnat_add_mult_distrib2
  5172   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5173   right_inverse <-- hypreal_mult_inverse
  5174   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5175   order_refl <-- {hypreal,hypnat}_le_refl
  5176   order_trans <-- {hypreal,hypnat}_le_trans
  5177   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5178   order_less_le <-- {hypreal,hypnat}_less_le
  5179   linorder_linear <-- {hypreal,hypnat}_le_linear
  5180   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5181   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5182   add_nonneg_nonneg <-- hypreal_le_add_order
  5183 
  5184 * Hyperreal: Separate theorems having to do with type-specific
  5185 versions of constants have been merged into theorems that apply to the
  5186 new polymorphic constants (INCOMPATIBILITY):
  5187 
  5188   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5189   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5190   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5191   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5192   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5193   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5194   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5195   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5196   STAR_diff <-- {STAR,STARC}_diff
  5197   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5198     STARC_hcomplex_of_complex}_image_subset
  5199   starset_n_Un <-- starset{Nat,C}_n_Un
  5200   starset_n_Int <-- starset{Nat,C}_n_Int
  5201   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5202   starset_n_diff <-- starset{Nat,C}_n_diff
  5203   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5204   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5205   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5206   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5207   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5208   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5209   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5210   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5211   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5212   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5213   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5214   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5215   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5216   starfun_diff <-- starfun{C,RC,CR}_diff
  5217   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5218   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5219   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5220   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5221   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5222   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5223   starfun_Id <-- starfunC_Id
  5224   starfun_approx <-- starfun{Nat,CR}_approx
  5225   starfun_capprox <-- starfun{C,RC}_capprox
  5226   starfun_abs <-- starfunNat_rabs
  5227   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5228   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5229   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5230   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5231   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5232   starfun_add_approx <-- starfunCR_add_approx
  5233   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5234   starfun_divide <-- starfun{C,CR,RC}_divide
  5235   starfun_n <-- starfun{Nat,C}_n
  5236   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5237   starfun_n_add <-- starfun{Nat,C}_n_add
  5238   starfun_n_add_minus <-- starfunNat_n_add_minus
  5239   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5240   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5241   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5242 
  5243   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5244   star_n_minus <-- {hypreal,hcomplex}_minus
  5245   star_n_diff <-- {hypreal,hcomplex}_diff
  5246   star_n_mult <-- {hypreal,hcomplex}_mult
  5247   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5248   star_n_le <-- {hypreal,hypnat}_le
  5249   star_n_less <-- {hypreal,hypnat}_less
  5250   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5251   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5252   star_n_abs <-- hypreal_hrabs
  5253   star_n_divide <-- hcomplex_divide
  5254 
  5255   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5256   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5257   star_of_diff <-- hypreal_of_real_diff
  5258   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5259   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5260   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5261   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5262   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5263   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5264   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5265   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5266   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5267   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5268   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5269   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5270   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5271   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5272   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5273   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5274   star_of_power <-- hypreal_of_real_power
  5275   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5276 
  5277 * Hyperreal: new method "transfer" that implements the transfer
  5278 principle of nonstandard analysis. With a subgoal that mentions
  5279 nonstandard types like "'a star", the command "apply transfer"
  5280 replaces it with an equivalent one that mentions only standard types.
  5281 To be successful, all free variables must have standard types; non-
  5282 standard variables must have explicit universal quantifiers.
  5283 
  5284 * Hyperreal: A theory of Taylor series.
  5285 
  5286 
  5287 *** HOLCF ***
  5288 
  5289 * Discontinued special version of 'constdefs' (which used to support
  5290 continuous functions) in favor of the general Pure one with full
  5291 type-inference.
  5292 
  5293 * New simplification procedure for solving continuity conditions; it
  5294 is much faster on terms with many nested lambda abstractions (cubic
  5295 instead of exponential time).
  5296 
  5297 * New syntax for domain package: selector names are now optional.
  5298 Parentheses should be omitted unless argument is lazy, for example:
  5299 
  5300   domain 'a stream = cons "'a" (lazy "'a stream")
  5301 
  5302 * New command 'fixrec' for defining recursive functions with pattern
  5303 matching; defining multiple functions with mutual recursion is also
  5304 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5305 sinr, or any data constructor defined by the domain package. The given
  5306 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5307 syntax and examples.
  5308 
  5309 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5310 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5311 but the proof obligation additionally includes an admissibility
  5312 requirement. The packages generate instances of class cpo or pcpo,
  5313 with continuity and strictness theorems for Rep and Abs.
  5314 
  5315 * HOLCF: Many theorems have been renamed according to a more standard naming
  5316 scheme (INCOMPATIBILITY):
  5317 
  5318   foo_inject:  "foo$x = foo$y ==> x = y"
  5319   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5320   foo_less:    "(foo$x << foo$y) = (x << y)"
  5321   foo_strict:  "foo$UU = UU"
  5322   foo_defined: "... ==> foo$x ~= UU"
  5323   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5324 
  5325 
  5326 *** ZF ***
  5327 
  5328 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5329 including the First Isomorphism Theorem (on quotienting by the kernel
  5330 of a homomorphism).
  5331 
  5332 * ZF/Simplifier: install second copy of type solver that actually
  5333 makes use of TC rules declared to Isar proof contexts (or locales);
  5334 the old version is still required for ML proof scripts.
  5335 
  5336 
  5337 *** Cube ***
  5338 
  5339 * Converted to Isar theory format; use locales instead of axiomatic
  5340 theories.
  5341 
  5342 
  5343 *** ML ***
  5344 
  5345 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5346 for ||>, ||>>, |>>,
  5347 
  5348 * Pure/library.ML no longer defines its own option datatype, but uses
  5349 that of the SML basis, which has constructors NONE and SOME instead of
  5350 None and Some, as well as exception Option.Option instead of OPTION.
  5351 The functions the, if_none, is_some, is_none have been adapted
  5352 accordingly, while Option.map replaces apsome.
  5353 
  5354 * Pure/library.ML: the exception LIST has been given up in favour of
  5355 the standard exceptions Empty and Subscript, as well as
  5356 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5357 superceded by the standard hd and tl functions etc.
  5358 
  5359 A number of basic list functions are no longer exported to the ML
  5360 toplevel, as they are variants of predefined functions.  The following
  5361 suggests how one can translate existing code:
  5362 
  5363     rev_append xs ys = List.revAppend (xs, ys)
  5364     nth_elem (i, xs) = List.nth (xs, i)
  5365     last_elem xs = List.last xs
  5366     flat xss = List.concat xss
  5367     seq fs = List.app fs
  5368     partition P xs = List.partition P xs
  5369     mapfilter f xs = List.mapPartial f xs
  5370 
  5371 * Pure/library.ML: several combinators for linear functional
  5372 transformations, notably reverse application and composition:
  5373 
  5374   x |> f                f #> g
  5375   (x, y) |-> f          f #-> g
  5376 
  5377 * Pure/library.ML: introduced/changed precedence of infix operators:
  5378 
  5379   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5380   infix 2 ?;
  5381   infix 3 o oo ooo oooo;
  5382   infix 4 ~~ upto downto;
  5383 
  5384 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5385 infix operators.
  5386 
  5387 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5388 fold_map support linear functional transformations and nesting.  For
  5389 example:
  5390 
  5391   fold f [x1, ..., xN] y =
  5392     y |> f x1 |> ... |> f xN
  5393 
  5394   (fold o fold) f [xs1, ..., xsN] y =
  5395     y |> fold f xs1 |> ... |> fold f xsN
  5396 
  5397   fold f [x1, ..., xN] =
  5398     f x1 #> ... #> f xN
  5399 
  5400   (fold o fold) f [xs1, ..., xsN] =
  5401     fold f xs1 #> ... #> fold f xsN
  5402 
  5403 * Pure/library.ML: the following selectors on type 'a option are
  5404 available:
  5405 
  5406   the:               'a option -> 'a  (*partial*)
  5407   these:             'a option -> 'a  where 'a = 'b list
  5408   the_default: 'a -> 'a option -> 'a
  5409   the_list:          'a option -> 'a list
  5410 
  5411 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5412 basic operations for association lists, following natural argument
  5413 order; moreover the explicit equality predicate passed here avoids
  5414 potentially expensive polymorphic runtime equality checks.
  5415 The old functions may be expressed as follows:
  5416 
  5417   assoc = uncurry (AList.lookup (op =))
  5418   assocs = these oo AList.lookup (op =)
  5419   overwrite = uncurry (AList.update (op =)) o swap
  5420 
  5421 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5422 
  5423   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5424   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5425 
  5426 replacing make_keylist and keyfilter (occassionally used)
  5427 Naive rewrites:
  5428 
  5429   make_keylist = AList.make
  5430   keyfilter = AList.find (op =)
  5431 
  5432 * eq_fst and eq_snd now take explicit equality parameter, thus
  5433   avoiding eqtypes. Naive rewrites:
  5434 
  5435     eq_fst = eq_fst (op =)
  5436     eq_snd = eq_snd (op =)
  5437 
  5438 * Removed deprecated apl and apr (rarely used).
  5439   Naive rewrites:
  5440 
  5441     apl (n, op) =>>= curry op n
  5442     apr (op, m) =>>= fn n => op (n, m)
  5443 
  5444 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5445 provides a reasonably efficient light-weight implementation of sets as
  5446 lists.
  5447 
  5448 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5449 few new operations; existing lookup and update are now curried to
  5450 follow natural argument order (for use with fold etc.);
  5451 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5452 
  5453 * Pure/General: output via the Isabelle channels of
  5454 writeln/warning/error etc. is now passed through Output.output, with a
  5455 hook for arbitrary transformations depending on the print_mode
  5456 (cf. Output.add_mode -- the first active mode that provides a output
  5457 function wins).  Already formatted output may be embedded into further
  5458 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5459 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5460 accommodate easy composition of diagnostic messages etc.  Programmers
  5461 rarely need to care about Output.output or Output.raw at all, with
  5462 some notable exceptions: Output.output is required when bypassing the
  5463 standard channels (writeln etc.), or in token translations to produce
  5464 properly formatted results; Output.raw is required when capturing
  5465 already output material that will eventually be presented to the user
  5466 a second time.  For the default print mode, both Output.output and
  5467 Output.raw have no effect.
  5468 
  5469 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5470 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5471 cumulative results are displayed at the end of a batch session.
  5472 
  5473 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5474 replaced by File.platform_path and File.shell_path (with appropriate
  5475 hooks).  This provides a clean interface for unusual systems where the
  5476 internal and external process view of file names are different.
  5477 
  5478 * Pure: more efficient orders for basic syntactic entities: added
  5479 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5480 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5481 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5482 orders now -- potential INCOMPATIBILITY for code that depends on a
  5483 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5484 Library.sort_strings on result).
  5485 
  5486 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5487 fold_types traverse types/terms from left to right, observing natural
  5488 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5489 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5490 
  5491 * Pure: name spaces have been refined, with significant changes of the
  5492 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5493 to extern(_table).  The plain name entry path is superceded by a
  5494 general 'naming' context, which also includes the 'policy' to produce
  5495 a fully qualified name and external accesses of a fully qualified
  5496 name; NameSpace.extend is superceded by context dependent
  5497 Sign.declare_name.  Several theory and proof context operations modify
  5498 the naming context.  Especially note Theory.restore_naming and
  5499 ProofContext.restore_naming to get back to a sane state; note that
  5500 Theory.add_path is no longer sufficient to recover from
  5501 Theory.absolute_path in particular.
  5502 
  5503 * Pure: new flags short_names (default false) and unique_names
  5504 (default true) for controlling output of qualified names.  If
  5505 short_names is set, names are printed unqualified.  If unique_names is
  5506 reset, the name prefix is reduced to the minimum required to achieve
  5507 the original result when interning again, even if there is an overlap
  5508 with earlier declarations.
  5509 
  5510 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5511 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5512 (useful for printing error messages).  INCOMPATIBILITY.
  5513 
  5514 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5515 Theory.theory are now identified, referring to the universal
  5516 Context.theory (see Pure/context.ML).  Actual signature and theory
  5517 content is managed as theory data.  The old code and interfaces were
  5518 spread over many files and structures; the new arrangement introduces
  5519 considerable INCOMPATIBILITY to gain more clarity:
  5520 
  5521   Context -- theory management operations (name, identity, inclusion,
  5522     parents, ancestors, merge, etc.), plus generic theory data;
  5523 
  5524   Sign -- logical signature and syntax operations (declaring consts,
  5525     types, etc.), plus certify/read for common entities;
  5526 
  5527   Theory -- logical theory operations (stating axioms, definitions,
  5528     oracles), plus a copy of logical signature operations (consts,
  5529     types, etc.); also a few basic management operations (Theory.copy,
  5530     Theory.merge, etc.)
  5531 
  5532 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5533 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5534 for convenience -- they merely return the theory.
  5535 
  5536 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5537 
  5538 * Pure: the Isar proof context type is already defined early in Pure
  5539 as Context.proof (note that ProofContext.context and Proof.context are
  5540 aliases, where the latter is the preferred name).  This enables other
  5541 Isabelle components to refer to that type even before Isar is present.
  5542 
  5543 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5544 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5545 any of these kinds.  For example, Sign.intern typeK is now
  5546 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5547 Theory.hide_types.  Also note that former
  5548 Theory.hide_classes/types/consts are now
  5549 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5550 internalize their arguments!  INCOMPATIBILITY.
  5551 
  5552 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5553 datatype thmref (with constructors Name and NameSelection) instead of
  5554 plain string -- INCOMPATIBILITY;
  5555 
  5556 * Pure: cases produced by proof methods specify options, where NONE
  5557 means to remove case bindings -- INCOMPATIBILITY in
  5558 (RAW_)METHOD_CASES.
  5559 
  5560 * Pure: the following operations retrieve axioms or theorems from a
  5561 theory node or theory hierarchy, respectively:
  5562 
  5563   Theory.axioms_of: theory -> (string * term) list
  5564   Theory.all_axioms_of: theory -> (string * term) list
  5565   PureThy.thms_of: theory -> (string * thm) list
  5566   PureThy.all_thms_of: theory -> (string * thm) list
  5567 
  5568 * Pure: print_tac now outputs the goal through the trace channel.
  5569 
  5570 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5571 Reference Toplevel.debug (default false) controls detailed printing
  5572 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5573 controls execution profiling -- set to 1 for time and 2 for space
  5574 (both increase the runtime).
  5575 
  5576 * Isar session: The initial use of ROOT.ML is now always timed,
  5577 i.e. the log will show the actual process times, in contrast to the
  5578 elapsed wall-clock time that the outer shell wrapper produces.
  5579 
  5580 * Simplifier: improved handling of bound variables (nameless
  5581 representation, avoid allocating new strings).  Simprocs that invoke
  5582 the Simplifier recursively should use Simplifier.inherit_bounds to
  5583 avoid local name clashes.  Failure to do so produces warnings
  5584 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5585 for further details.
  5586 
  5587 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5588 bindings for all theorems stored within a given theory; this may help
  5589 in porting non-Isar theories to Isar ones, while keeping ML proof
  5590 scripts for the time being.
  5591 
  5592 * ML operator HTML.with_charset specifies the charset begin used for
  5593 generated HTML files.  For example:
  5594 
  5595   HTML.with_charset "utf-8" use_thy "Hebrew";
  5596   HTML.with_charset "utf-8" use_thy "Chinese";
  5597 
  5598 
  5599 *** System ***
  5600 
  5601 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5602 isabelle, isatool etc.).
  5603 
  5604 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5605 isatool doc, isatool mkdir, display_drafts etc.).
  5606 
  5607 * isatool usedir: option -f allows specification of the ML file to be
  5608 used by Isabelle; default is ROOT.ML.
  5609 
  5610 * New isatool version outputs the version identifier of the Isabelle
  5611 distribution being used.
  5612 
  5613 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5614 (containing Boolean satisfiability problems) into Isabelle/HOL
  5615 theories.
  5616 
  5617 
  5618 
  5619 New in Isabelle2004 (April 2004)
  5620 --------------------------------
  5621 
  5622 *** General ***
  5623 
  5624 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5625   Replaces linorder.ML.
  5626 
  5627 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5628   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5629   (\<a>...\<z>), are now considered normal letters, and can therefore
  5630   be used anywhere where an ASCII letter (a...zA...Z) has until
  5631   now. COMPATIBILITY: This obviously changes the parsing of some
  5632   terms, especially where a symbol has been used as a binder, say
  5633   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5634   as an identifier.  Fix it by inserting a space around former
  5635   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5636   existing theory and ML files.
  5637 
  5638 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5639 
  5640 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5641   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5642   a normal (but invisible) letter. For multiple letter subscripts repeat
  5643   \<^isub> like this: x\<^isub>1\<^isub>2.
  5644 
  5645 * Pure: There are now sub-/superscripts that can span more than one
  5646   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5647   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5648   superscript. The new control characters are not identifier parts.
  5649 
  5650 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5651   content of "..." to the latex file instead of \isacntrl... . The "..."
  5652   may consist of any printable characters excluding the end bracket >.
  5653 
  5654 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5655   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5656   declare constants "final", which prevents their being given a definition
  5657   later.  It is useful for constants whose behaviour is fixed axiomatically
  5658   rather than definitionally, such as the meta-logic connectives.
  5659 
  5660 * Pure: 'instance' now handles general arities with general sorts
  5661   (i.e. intersections of classes),
  5662 
  5663 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5664   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5665   It can be changed to alter the colors/layout of generated pages.
  5666 
  5667 
  5668 *** Isar ***
  5669 
  5670 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5671   cut_tac, subgoal_tac and thin_tac:
  5672   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5673     locales are no longer forced to write Isar proof scripts.
  5674     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5675     emulations.
  5676   - INCOMPATIBILITY: names of variables to be instantiated may no
  5677     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5678     This is consistent with the instantiation attribute "where".
  5679 
  5680 * Attributes "where" and "of":
  5681   - Now take type variables of instantiated theorem into account when reading
  5682     the instantiation string.  This fixes a bug that caused instantiated
  5683     theorems to have too special types in some circumstances.
  5684   - "where" permits explicit instantiations of type variables.
  5685 
  5686 * Calculation commands "moreover" and "also" no longer interfere with
  5687   current facts ("this"), admitting arbitrary combinations with "then"
  5688   and derived forms.
  5689 
  5690 * Locales:
  5691   - Goal statements involving the context element "includes" no longer
  5692     generate theorems with internal delta predicates (those ending on
  5693     "_axioms") in the premise.
  5694     Resolve particular premise with <locale>.intro to obtain old form.
  5695   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5696     specification and "includes" elements in goal statement.
  5697   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5698     [intro?] and [elim?] (respectively) by default.
  5699   - Experimental command for instantiation of locales in proof contexts:
  5700         instantiate <label>[<attrs>]: <loc>
  5701     Instantiates locale <loc> and adds all its theorems to the current context
  5702     taking into account their attributes.  Label and attrs are optional
  5703     modifiers, like in theorem declarations.  If present, names of
  5704     instantiated theorems are qualified with <label>, and the attributes
  5705     <attrs> are applied after any attributes these theorems might have already.
  5706       If the locale has assumptions, a chained fact of the form
  5707     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5708     are derived.  The command does not support old-style locales declared
  5709     with "locale (open)".
  5710       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5711 
  5712 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5713   (Isar) contexts.
  5714 
  5715 
  5716 *** HOL ***
  5717 
  5718 * Proof import: new image HOL4 contains the imported library from
  5719   the HOL4 system with about 2500 theorems. It is imported by
  5720   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5721   can be used like any other Isabelle image.  See
  5722   HOL/Import/HOL/README for more information.
  5723 
  5724 * Simplifier:
  5725   - Much improved handling of linear and partial orders.
  5726     Reasoners for linear and partial orders are set up for type classes
  5727     "linorder" and "order" respectively, and are added to the default simpset
  5728     as solvers.  This means that the simplifier can build transitivity chains
  5729     to solve goals from the assumptions.
  5730   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5731     of blast or auto after simplification become unnecessary because the goal
  5732     is solved by simplification already.
  5733 
  5734 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5735     all proved in axiomatic type classes for semirings, rings and fields.
  5736 
  5737 * Numerics:
  5738   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5739     now formalized using the Ring_and_Field theory mentioned above.
  5740   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5741     than before, because now they are set up once in a generic manner.
  5742   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5743     Look for the general versions in Ring_and_Field (and Power if they concern
  5744     exponentiation).
  5745 
  5746 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5747 
  5748 * Records:
  5749   - Record types are now by default printed with their type abbreviation
  5750     instead of the list of all field types. This can be configured via
  5751     the reference "print_record_type_abbr".
  5752   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5753     (not enabled by default).
  5754   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5755     EX x. x = sel r to True (not enabled by default).
  5756   - Tactic "record_split_simp_tac" to split and simplify records added.
  5757 
  5758 * 'specification' command added, allowing for definition by
  5759   specification.  There is also an 'ax_specification' command that
  5760   introduces the new constants axiomatically.
  5761 
  5762 * arith(_tac) is now able to generate counterexamples for reals as well.
  5763 
  5764 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5765 
  5766 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5767   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5768 
  5769 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5770   matrix theory to linear programming.
  5771 
  5772 * Unions and Intersections:
  5773   The latex output syntax of UN and INT has been changed
  5774   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5775   i.e. the index formulae has become a subscript.
  5776   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5777 
  5778 * Unions and Intersections over Intervals:
  5779   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5780   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5781   like in normal math, and corresponding versions for < and for intersection.
  5782 
  5783 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5784   lexicographic dictonary ordering has been added as "lexord".
  5785 
  5786 * ML: the legacy theory structures Int and List have been removed. They had
  5787   conflicted with ML Basis Library structures having the same names.
  5788 
  5789 * 'refute' command added to search for (finite) countermodels.  Only works
  5790   for a fragment of HOL.  The installation of an external SAT solver is
  5791   highly recommended.  See "HOL/Refute.thy" for details.
  5792 
  5793 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5794   formulae under an assignment of free variables to random values.
  5795   In contrast to 'refute', it can deal with inductive datatypes,
  5796   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5797   for examples.
  5798 
  5799 
  5800 *** HOLCF ***
  5801 
  5802 * Streams now come with concatenation and are part of the HOLCF image
  5803 
  5804 
  5805 
  5806 New in Isabelle2003 (May 2003)
  5807 ------------------------------
  5808 
  5809 *** General ***
  5810 
  5811 * Provers/simplifier:
  5812 
  5813   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5814     Assumptions are now subject to complete mutual simplification,
  5815     not just from left to right. The simplifier now preserves
  5816     the order of assumptions.
  5817 
  5818     Potential INCOMPATIBILITY:
  5819 
  5820     -- simp sometimes diverges where the old version did
  5821        not, e.g. invoking simp on the goal
  5822 
  5823         [| P (f x); y = x; f x = f y |] ==> Q
  5824 
  5825        now gives rise to the infinite reduction sequence
  5826 
  5827         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5828 
  5829        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5830        kind of problem.
  5831 
  5832     -- Tactics combining classical reasoner and simplification (such as auto)
  5833        are also affected by this change, because many of them rely on
  5834        simp. They may sometimes diverge as well or yield a different numbers
  5835        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5836        in case of problems. Sometimes subsequent calls to the classical
  5837        reasoner will fail because a preceeding call to the simplifier too
  5838        eagerly simplified the goal, e.g. deleted redundant premises.
  5839 
  5840   - The simplifier trace now shows the names of the applied rewrite rules
  5841 
  5842   - You can limit the number of recursive invocations of the simplifier
  5843     during conditional rewriting (where the simplifie tries to solve the
  5844     conditions before applying the rewrite rule):
  5845     ML "simp_depth_limit := n"
  5846     where n is an integer. Thus you can force termination where previously
  5847     the simplifier would diverge.
  5848 
  5849   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5850 
  5851   - No longer aborts on failed congruence proof.  Instead, the
  5852     congruence is ignored.
  5853 
  5854 * Pure: New generic framework for extracting programs from constructive
  5855   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5856   as HOL/Extraction for some case studies.
  5857 
  5858 * Pure: The main goal of the proof state is no longer shown by default, only
  5859 the subgoals. This behaviour is controlled by a new flag.
  5860    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5861 (ML: Proof.show_main_goal).
  5862 
  5863 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5864 rules whose conclusion matches subgoal 1:
  5865       PG menu: Isabelle/Isar -> Show me -> matching rules
  5866 The rules are ordered by how closely they match the subgoal.
  5867 In particular, rules that solve a subgoal outright are displayed first
  5868 (or rather last, the way they are printed).
  5869 (ML: ProofGeneral.print_intros())
  5870 
  5871 * Pure: New flag trace_unify_fail causes unification to print
  5872 diagnostic information (PG: in trace buffer) when it fails. This is
  5873 useful for figuring out why single step proofs like rule, erule or
  5874 assumption failed.
  5875 
  5876 * Pure: Locale specifications now produce predicate definitions
  5877 according to the body of text (covering assumptions modulo local
  5878 definitions); predicate "loc_axioms" covers newly introduced text,
  5879 while "loc" is cumulative wrt. all included locale expressions; the
  5880 latter view is presented only on export into the global theory
  5881 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5882 on the old view without predicates;
  5883 
  5884 * Pure: predefined locales "var" and "struct" are useful for sharing
  5885 parameters (as in CASL, for example); just specify something like
  5886 ``var x + var y + struct M'' as import;
  5887 
  5888 * Pure: improved thms_containing: proper indexing of facts instead of
  5889 raw theorems; check validity of results wrt. current name space;
  5890 include local facts of proof configuration (also covers active
  5891 locales), cover fixed variables in index; may use "_" in term
  5892 specification; an optional limit for the number of printed facts may
  5893 be given (the default is 40);
  5894 
  5895 * Pure: disallow duplicate fact bindings within new-style theory files
  5896 (batch-mode only);
  5897 
  5898 * Provers: improved induct method: assumptions introduced by case
  5899 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5900 the goal statement); "foo" still refers to all facts collectively;
  5901 
  5902 * Provers: the function blast.overloaded has been removed: all constants
  5903 are regarded as potentially overloaded, which improves robustness in exchange
  5904 for slight decrease in efficiency;
  5905 
  5906 * Provers/linorder: New generic prover for transitivity reasoning over
  5907 linear orders.  Note: this prover is not efficient!
  5908 
  5909 * Isar: preview of problems to finish 'show' now produce an error
  5910 rather than just a warning (in interactive mode);
  5911 
  5912 
  5913 *** HOL ***
  5914 
  5915 * arith(_tac)
  5916 
  5917  - Produces a counter example if it cannot prove a goal.
  5918    Note that the counter example may be spurious if the goal is not a formula
  5919    of quantifier-free linear arithmetic.
  5920    In ProofGeneral the counter example appears in the trace buffer.
  5921 
  5922  - Knows about div k and mod k where k is a numeral of type nat or int.
  5923 
  5924  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5925    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5926    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5927 
  5928 * simp's arithmetic capabilities have been enhanced a bit: it now
  5929 takes ~= in premises into account (by performing a case split);
  5930 
  5931 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5932 are distributed over a sum of terms;
  5933 
  5934 * New tactic "trans_tac" and method "trans" instantiate
  5935 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5936 "<=", "<" and "=").
  5937 
  5938 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5939 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5940 
  5941 * 'typedef' command has new option "open" to suppress the set
  5942 definition;
  5943 
  5944 * functions Min and Max on finite sets have been introduced (theory
  5945 Finite_Set);
  5946 
  5947 * attribute [symmetric] now works for relations as well; it turns
  5948 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5949 
  5950 * induct over a !!-quantified statement (say !!x1..xn):
  5951   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5952 
  5953 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5954 %x. None. Warning: empty_def now refers to the previously hidden definition
  5955 of the empty set.
  5956 
  5957 * Algebra: formalization of classical algebra.  Intended as base for
  5958 any algebraic development in Isabelle.  Currently covers group theory
  5959 (up to Sylow's theorem) and ring theory (Universal Property of
  5960 Univariate Polynomials).  Contributions welcome;
  5961 
  5962 * GroupTheory: deleted, since its material has been moved to Algebra;
  5963 
  5964 * Complex: new directory of the complex numbers with numeric constants,
  5965 nonstandard complex numbers, and some complex analysis, standard and
  5966 nonstandard (Jacques Fleuriot);
  5967 
  5968 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  5969 
  5970 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  5971 Fleuriot);
  5972 
  5973 * Real/HahnBanach: updated and adapted to locales;
  5974 
  5975 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  5976 Gray and Kramer);
  5977 
  5978 * UNITY: added the Meier-Sanders theory of progress sets;
  5979 
  5980 * MicroJava: bytecode verifier and lightweight bytecode verifier
  5981 as abstract algorithms, instantiated to the JVM;
  5982 
  5983 * Bali: Java source language formalization. Type system, operational
  5984 semantics, axiomatic semantics. Supported language features:
  5985 classes, interfaces, objects,virtual methods, static methods,
  5986 static/instance fields, arrays, access modifiers, definite
  5987 assignment, exceptions.
  5988 
  5989 
  5990 *** ZF ***
  5991 
  5992 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  5993 universe, etc.);
  5994 
  5995 * Main ZF: virtually all theories converted to new-style format;
  5996 
  5997 
  5998 *** ML ***
  5999 
  6000 * Pure: Tactic.prove provides sane interface for internal proofs;
  6001 omits the infamous "standard" operation, so this is more appropriate
  6002 than prove_goalw_cterm in many situations (e.g. in simprocs);
  6003 
  6004 * Pure: improved error reporting of simprocs;
  6005 
  6006 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  6007 up simprocs;
  6008 
  6009 
  6010 *** Document preparation ***
  6011 
  6012 * uses \par instead of \\ for line breaks in theory text. This may
  6013 shift some page breaks in large documents. To get the old behaviour
  6014 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  6015 
  6016 * minimized dependencies of isabelle.sty and isabellesym.sty on
  6017 other packages
  6018 
  6019 * \<euro> now needs package babel/greek instead of marvosym (which
  6020 broke \Rightarrow)
  6021 
  6022 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  6023 textcomp package)
  6024 
  6025 
  6026 
  6027 New in Isabelle2002 (March 2002)
  6028 --------------------------------
  6029 
  6030 *** Document preparation ***
  6031 
  6032 * greatly simplified document preparation setup, including more
  6033 graceful interpretation of isatool usedir -i/-d/-D options, and more
  6034 instructive isatool mkdir; users should basically be able to get
  6035 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  6036 users may run a separate document processing stage manually like this:
  6037 "isatool usedir -D output HOL Test && isatool document Test/output";
  6038 
  6039 * theory dependency graph may now be incorporated into documents;
  6040 isatool usedir -g true will produce session_graph.eps/.pdf for use
  6041 with \includegraphics of LaTeX;
  6042 
  6043 * proper spacing of consecutive markup elements, especially text
  6044 blocks after section headings;
  6045 
  6046 * support bold style (for single symbols only), input syntax is like
  6047 this: "\<^bold>\<alpha>" or "\<^bold>A";
  6048 
  6049 * \<bullet> is now output as bold \cdot by default, which looks much
  6050 better in printed text;
  6051 
  6052 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  6053 note that these symbols are currently unavailable in Proof General /
  6054 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  6055 
  6056 * isatool latex no longer depends on changed TEXINPUTS, instead
  6057 isatool document copies the Isabelle style files to the target
  6058 location;
  6059 
  6060 
  6061 *** Isar ***
  6062 
  6063 * Pure/Provers: improved proof by cases and induction;
  6064   - 'case' command admits impromptu naming of parameters (such as
  6065     "case (Suc n)");
  6066   - 'induct' method divinates rule instantiation from the inductive
  6067     claim; no longer requires excessive ?P bindings for proper
  6068     instantiation of cases;
  6069   - 'induct' method properly enumerates all possibilities of set/type
  6070     rules; as a consequence facts may be also passed through *type*
  6071     rules without further ado;
  6072   - 'induct' method now derives symbolic cases from the *rulified*
  6073     rule (before it used to rulify cases stemming from the internal
  6074     atomized version); this means that the context of a non-atomic
  6075     statement becomes is included in the hypothesis, avoiding the
  6076     slightly cumbersome show "PROP ?case" form;
  6077   - 'induct' may now use elim-style induction rules without chaining
  6078     facts, using ``missing'' premises from the goal state; this allows
  6079     rules stemming from inductive sets to be applied in unstructured
  6080     scripts, while still benefitting from proper handling of non-atomic
  6081     statements; NB: major inductive premises need to be put first, all
  6082     the rest of the goal is passed through the induction;
  6083   - 'induct' proper support for mutual induction involving non-atomic
  6084     rule statements (uses the new concept of simultaneous goals, see
  6085     below);
  6086   - append all possible rule selections, but only use the first
  6087     success (no backtracking);
  6088   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  6089   - undeclared rule case names default to numbers 1, 2, 3, ...;
  6090   - added 'print_induct_rules' (covered by help item in recent Proof
  6091     General versions);
  6092   - moved induct/cases attributes to Pure, methods to Provers;
  6093   - generic method setup instantiated for FOL and HOL;
  6094 
  6095 * Pure: support multiple simultaneous goal statements, for example
  6096 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  6097 meta-level mechanism, this acts as if several individual goals had
  6098 been stated separately; in particular common proof methods need to be
  6099 repeated in order to cover all claims; note that a single elimination
  6100 step is *not* sufficient to establish the two conjunctions, so this
  6101 fails:
  6102 
  6103   assume "A & B" then have A and B ..   (*".." fails*)
  6104 
  6105 better use "obtain" in situations as above; alternative refer to
  6106 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  6107 
  6108 * Pure: proper integration with ``locales''; unlike the original
  6109 version by Florian Kammller, Isar locales package high-level proof
  6110 contexts rather than raw logical ones (e.g. we admit to include
  6111 attributes everywhere); operations on locales include merge and
  6112 rename; support for implicit arguments (``structures''); simultaneous
  6113 type-inference over imports and text; see also HOL/ex/Locales.thy for
  6114 some examples;
  6115 
  6116 * Pure: the following commands have been ``localized'', supporting a
  6117 target locale specification "(in name)": 'lemma', 'theorem',
  6118 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  6119 stored both within the locale and at the theory level (exported and
  6120 qualified by the locale name);
  6121 
  6122 * Pure: theory goals may now be specified in ``long'' form, with
  6123 ad-hoc contexts consisting of arbitrary locale elements. for example
  6124 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  6125 definitions may be given, too); the result is a meta-level rule with
  6126 the context elements being discharged in the obvious way;
  6127 
  6128 * Pure: new proof command 'using' allows to augment currently used
  6129 facts after a goal statement ('using' is syntactically analogous to
  6130 'apply', but acts on the goal's facts only); this allows chained facts
  6131 to be separated into parts given before and after a claim, as in
  6132 ``from a and b have C using d and e <proof>'';
  6133 
  6134 * Pure: renamed "antecedent" case to "rule_context";
  6135 
  6136 * Pure: new 'judgment' command records explicit information about the
  6137 object-logic embedding (used by several tools internally); no longer
  6138 use hard-wired "Trueprop";
  6139 
  6140 * Pure: added 'corollary' command;
  6141 
  6142 * Pure: fixed 'token_translation' command;
  6143 
  6144 * Pure: removed obsolete 'exported' attribute;
  6145 
  6146 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  6147 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  6148 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  6149 
  6150 * Pure: method 'atomize' presents local goal premises as object-level
  6151 statements (atomic meta-level propositions); setup controlled via
  6152 rewrite rules declarations of 'atomize' attribute; example
  6153 application: 'induct' method with proper rule statements in improper
  6154 proof *scripts*;
  6155 
  6156 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  6157 now consider the syntactic context of assumptions, giving a better
  6158 chance to get type-inference of the arguments right (this is
  6159 especially important for locales);
  6160 
  6161 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  6162 mode;
  6163 
  6164 * Pure/obtain: the formal conclusion "thesis", being marked as
  6165 ``internal'', may no longer be reference directly in the text;
  6166 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  6167 situations;
  6168 
  6169 * Pure: generic 'sym' attribute which declares a rule both as pure
  6170 'elim?' and for the 'symmetric' operation;
  6171 
  6172 * Pure: marginal comments ``--'' may now occur just anywhere in the
  6173 text; the fixed correlation with particular command syntax has been
  6174 discontinued;
  6175 
  6176 * Pure: new method 'rules' is particularly well-suited for proof
  6177 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  6178 but often produces more compact proof terms with less detours;
  6179 
  6180 * Pure/Provers/classical: simplified integration with pure rule
  6181 attributes and methods; the classical "intro?/elim?/dest?"
  6182 declarations coincide with the pure ones; the "rule" method no longer
  6183 includes classically swapped intros; "intro" and "elim" methods no
  6184 longer pick rules from the context; also got rid of ML declarations
  6185 AddXIs/AddXEs/AddXDs; all of this has some potential for
  6186 INCOMPATIBILITY;
  6187 
  6188 * Provers/classical: attribute 'swapped' produces classical inversions
  6189 of introduction rules;
  6190 
  6191 * Provers/simplifier: 'simplified' attribute may refer to explicit
  6192 rules instead of full simplifier context; 'iff' attribute handles
  6193 conditional rules;
  6194 
  6195 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  6196 
  6197 * HOL: 'recdef' now fails on unfinished automated proofs, use
  6198 "(permissive)" option to recover old behavior;
  6199 
  6200 * HOL: 'inductive' no longer features separate (collective) attributes
  6201 for 'intros' (was found too confusing);
  6202 
  6203 * HOL: properly declared induction rules less_induct and
  6204 wf_induct_rule;
  6205 
  6206 
  6207 *** HOL ***
  6208 
  6209 * HOL: moved over to sane numeral syntax; the new policy is as
  6210 follows:
  6211 
  6212   - 0 and 1 are polymorphic constants, which are defined on any
  6213   numeric type (nat, int, real etc.);
  6214 
  6215   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  6216   binary representation internally;
  6217 
  6218   - type nat has special constructor Suc, and generally prefers Suc 0
  6219   over 1::nat and Suc (Suc 0) over 2::nat;
  6220 
  6221 This change may cause significant problems of INCOMPATIBILITY; here
  6222 are some hints on converting existing sources:
  6223 
  6224   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  6225   entities, so expressions involving "-" (unary or binary minus) need
  6226   to be spaced properly;
  6227 
  6228   - existing occurrences of "1" may need to be constraint "1::nat" or
  6229   even replaced by Suc 0; similar for old "2";
  6230 
  6231   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  6232 
  6233   - remove all special provisions on numerals in proofs;