NEWS
author haftmann
Tue Aug 09 07:44:17 2011 +0200 (2011-08-09)
changeset 44086 c0847967a25a
parent 44081 730f7cced3a6
parent 44082 81e55342cb86
child 44103 cedaca00789f
permissions -rw-r--r--
merged
     1 Isabelle NEWS -- history user-relevant changes
     2 ==============================================
     3 
     4 New in this Isabelle version
     5 ----------------------------
     6 
     7 *** General ***
     8 
     9 * Theory loader: source files are identified by content via SHA1
    10 digests.  Discontinued former path/modtime identification and optional
    11 ISABELLE_FILE_IDENT plugin scripts.
    12 
    13 * Parallelization of nested Isar proofs is subject to
    14 Goal.parallel_proofs_threshold (default 100).  See also isabelle
    15 usedir option -Q.
    16 
    17 * Discontinued support for Poly/ML 5.2, which was the last version
    18 without proper multithreading and TimeLimit implementation.
    19 
    20 * Discontinued old lib/scripts/polyml-platform, which has been
    21 obsolete since Isabelle2009-2.
    22 
    23 * Theory loader: source files are exclusively located via the master
    24 directory of each theory node (where the .thy file itself resides).
    25 The global load path (such as src/HOL/Library) has been discontinued.
    26 Note that the path element ~~ may be used to reference theories in the
    27 Isabelle home folder -- for instance, "~~/src/HOL/Library/FuncSet".
    28 INCOMPATIBILITY.
    29 
    30 * Various optional external tools are referenced more robustly and
    31 uniformly by explicit Isabelle settings as follows:
    32 
    33   ISABELLE_CSDP   (formerly CSDP_EXE)
    34   ISABELLE_GHC    (formerly EXEC_GHC or GHC_PATH)
    35   ISABELLE_OCAML  (formerly EXEC_OCAML)
    36   ISABELLE_SWIPL  (formerly EXEC_SWIPL)
    37   ISABELLE_YAP    (formerly EXEC_YAP)
    38 
    39 Note that automated detection from the file-system or search path has
    40 been discontinued.  INCOMPATIBILITY.
    41 
    42 * Name space: former unsynchronized references are now proper
    43 configuration options, with more conventional names:
    44 
    45   long_names   ~> names_long
    46   short_names  ~> names_short
    47   unique_names ~> names_unique
    48 
    49 Minor INCOMPATIBILITY, need to declare options in context like this:
    50 
    51   declare [[names_unique = false]]
    52 
    53 * Literal facts `prop` may contain dummy patterns, e.g. `_ = _`.  Note
    54 that the result needs to be unique, which means fact specifications
    55 may have to be refined after enriching a proof context.
    56 
    57 * Isabelle/Isar reference manual provides more formal references in
    58 syntax diagrams.
    59 
    60 
    61 *** HOL ***
    62 
    63 * Classes bot and top require underlying partial order rather than preorder:
    64 uniqueness of bot and top is guaranteed.  INCOMPATIBILITY.
    65 
    66 * Class complete_lattice: generalized a couple of lemmas from sets;
    67 generalized theorems INF_cong and SUP_cong.  New type classes for complete
    68 boolean algebras and complete linear orders.  Lemmas Inf_less_iff,
    69 less_Sup_iff, INF_less_iff, less_SUP_iff now reside in class complete_linorder.
    70 Changes proposition of lemmas Inf_fun_def, Sup_fun_def, Inf_apply, Sup_apply.
    71 Redundant lemmas Inf_singleton, Sup_singleton, Inf_binary and Sup_binary have
    72 been discarded.
    73 More consistent and less misunderstandable names:
    74   INFI_def ~> INF_def
    75   SUPR_def ~> SUP_def
    76   le_SUPI ~> le_SUP_I
    77   le_SUPI2 ~> le_SUP_I2
    78   le_INFI ~> le_INF_I
    79   INFI_bool_eq ~> INF_bool_eq
    80   SUPR_bool_eq ~> SUP_bool_eq
    81   INFI_apply ~> INF_apply
    82   SUPR_apply ~> SUP_apply
    83 INCOMPATIBILITY.
    84 
    85 * Theorem collections ball_simps and bex_simps do not contain theorems referring
    86 to UNION any longer;  these have been moved to collection UN_ball_bex_simps.
    87 INCOMPATIBILITY.
    88 
    89 * Archimedean_Field.thy:
    90     floor now is defined as parameter of a separate type class floor_ceiling.
    91  
    92 * Finite_Set.thy: more coherent development of fold_set locales:
    93 
    94     locale fun_left_comm ~> locale comp_fun_commute
    95     locale fun_left_comm_idem ~> locale comp_fun_idem
    96     
    97 Both use point-free characterisation; interpretation proofs may need adjustment.
    98 INCOMPATIBILITY.
    99 
   100 * Code generation:
   101   - theory Library/Code_Char_ord provides native ordering of characters
   102     in the target language.
   103   - commands code_module and code_library are legacy, use export_code instead. 
   104   - method evaluation is legacy, use method eval instead.
   105   - legacy evaluator "SML" is deactivated by default. To activate it, add the following
   106     line in your theory:
   107       setup {* Value.add_evaluator ("SML", Codegen.eval_term) *}
   108  
   109 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
   110 
   111 * Nitpick:
   112   - Added "need" and "total_consts" options.
   113   - Reintroduced "show_skolems" option by popular demand.
   114   - Renamed attribute: nitpick_def ~> nitpick_unfold.
   115     INCOMPATIBILITY.
   116 
   117 * Sledgehammer:
   118   - sledgehammer available_provers ~> sledgehammer supported_provers.
   119     INCOMPATIBILITY.
   120   - Added support for SNARK and ToFoF-E on SystemOnTPTP and for simply typed
   121     TPTP problems (TFF).
   122   - Added "preplay_timeout", "slicing", "type_enc", "sound", "max_mono_iters",
   123     and "max_new_mono_instances" options.
   124   - Removed "explicit_apply" and "full_types" options as well as "Full Types"
   125     Proof General menu item. INCOMPATIBILITY.
   126 
   127 * Metis:
   128   - Removed "metisF" -- use "metis" instead. INCOMPATIBILITY.
   129   - Obsoleted "metisFT" -- use "metis (full_types)" instead. INCOMPATIBILITY.
   130 
   131 * "try":
   132   - Renamed "try_methods" and added "simp:", "intro:", "dest:", and "elim:"
   133     options. INCOMPATIBILITY.
   134   - Introduced "try" that not only runs "try_methods" but also "solve_direct",
   135     "sledgehammer", "quickcheck", and "nitpick".
   136 
   137 * Quickcheck:
   138   - Added "eval" option to evaluate terms for the found counterexample
   139     (currently only supported by the default (exhaustive) tester)
   140   - Added post-processing of terms to obtain readable counterexamples
   141     (currently only supported by the default (exhaustive) tester)
   142   - New counterexample generator quickcheck[narrowing] enables
   143     narrowing-based testing.
   144     It requires that the Glasgow Haskell compiler is installed and
   145     its location is known to Isabelle with the environment variable
   146     ISABELLE_GHC.
   147   - Removed quickcheck tester "SML" based on the SML code generator
   148     from HOL-Library
   149 
   150 * Function package: discontinued option "tailrec".
   151 INCOMPATIBILITY. Use partial_function instead.
   152 
   153 * HOL-Probability:
   154   - Caratheodory's extension lemma is now proved for ring_of_sets.
   155   - Infinite products of probability measures are now available.
   156   - Use extended reals instead of positive extended reals.
   157     INCOMPATIBILITY.
   158 
   159 * Old recdef package has been moved to Library/Old_Recdef.thy, where it
   160 must be loaded explicitly.  INCOMPATIBILITY.
   161 
   162 * Well-founded recursion combinator "wfrec" has been moved to
   163 Library/Wfrec.thy. INCOMPATIBILITY.
   164 
   165 * Theory Library/Nat_Infinity has been renamed to Library/Extended_Nat.
   166 The names of the following types and constants have changed:
   167   inat (type) ~> enat
   168   Fin         ~> enat
   169   Infty       ~> infinity (overloaded)
   170   iSuc        ~> eSuc
   171   the_Fin     ~> the_enat
   172 Every theorem name containing "inat", "Fin", "Infty", or "iSuc" has
   173 been renamed accordingly.
   174 
   175 * Limits.thy: Type "'a net" has been renamed to "'a filter", in
   176 accordance with standard mathematical terminology. INCOMPATIBILITY.
   177 
   178 
   179 *** Document preparation ***
   180 
   181 * Discontinued special treatment of hard tabulators, which are better
   182 avoided in the first place.  Implicit tab-width is 1.
   183 
   184 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
   185 isar-ref manual.
   186 
   187 * Antiquotation @{value} evaluates the given term and presents its result.
   188 
   189 * Localized \isabellestyle switch can be used within blocks or groups
   190 like this:
   191 
   192   \isabellestyle{it}  %preferred default
   193   {\isabellestylett @{text "typewriter stuff"}}
   194 
   195 * New term style "isub" as ad-hoc conversion of variables x1, y23 into
   196 subscripted form x\<^isub>1, y\<^isub>2\<^isub>3.
   197 
   198 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
   199 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
   200 
   201 
   202 *** ML ***
   203 
   204 * The inner syntax of sort/type/term/prop supports inlined YXML
   205 representations within quoted string tokens.  By encoding logical
   206 entities via Term_XML (in ML or Scala) concrete syntax can be
   207 bypassed, which is particularly useful for producing bits of text
   208 under external program control.
   209 
   210 * Antiquotations for ML and document preparation are managed as theory
   211 data, which requires explicit setup.
   212 
   213 * Isabelle_Process.is_active allows tools to check if the official
   214 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
   215 (better known as Proof General).
   216 
   217 * Structure Proof_Context follows standard naming scheme.  Old
   218 ProofContext is still available for some time as legacy alias.
   219 
   220 * Structure Timing provides various operations for timing; supersedes
   221 former start_timing/end_timing etc.
   222 
   223 * Path.print is the official way to show file-system paths to users
   224 (including quotes etc.).
   225 
   226 * Inner syntax: identifiers in parse trees of generic categories
   227 "logic", "aprop", "idt" etc. carry position information (disguised as
   228 type constraints).  Occasional INCOMPATIBILITY with non-compliant
   229 translations that choke on unexpected type constraints.  Positions can
   230 be stripped in ML translations via Syntax.strip_positions /
   231 Syntax.strip_positions_ast, or via the syntax constant
   232 "_strip_positions" within parse trees.  As last resort, positions can
   233 be disabled via the configuration option Syntax.positions, which is
   234 called "syntax_positions" in Isar attribute syntax.
   235 
   236 * Discontinued special status of various ML structures that contribute
   237 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
   238 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
   239 refer directly to Ast.Constant, Lexicon.is_identifier,
   240 Syntax_Trans.mk_binder_tr etc.
   241 
   242 * Typed print translation: discontinued show_sorts argument, which is
   243 already available via context of "advanced" translation.
   244 
   245 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
   246 goal states; body tactic needs to address all subgoals uniformly.
   247 
   248 * Slightly more special eq_list/eq_set, with shortcut involving
   249 pointer equality (assumes that eq relation is reflexive).
   250 
   251 * Classical tactics use proper Proof.context instead of historic types
   252 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
   253 operate directly on Proof.context.  Raw type claset retains its use as
   254 snapshot of the classical context, which can be recovered via
   255 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
   256 INCOMPATIBILITY, classical tactics and derived proof methods require
   257 proper Proof.context.
   258 
   259 * Scala layer provides JVM method invocation service for static
   260 methods of type (String)String, see Invoke_Scala.method in ML.
   261 For example:
   262 
   263   Invoke_Scala.method "java.lang.System.getProperty" "java.home"
   264 
   265 
   266 
   267 New in Isabelle2011 (January 2011)
   268 ----------------------------------
   269 
   270 *** General ***
   271 
   272 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
   273 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
   274 useful tooltips and hyperlinks produced from its static analysis.  The
   275 bundled component provides an executable Isabelle tool that can be run
   276 like this:
   277 
   278   Isabelle2011/bin/isabelle jedit
   279 
   280 * Significantly improved Isabelle/Isar implementation manual.
   281 
   282 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
   283 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
   284 while the default heap location within that directory lacks that extra
   285 suffix.  This isolates multiple Isabelle installations from each
   286 other, avoiding problems with old settings in new versions.
   287 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
   288 
   289 * Source files are always encoded as UTF-8, instead of old-fashioned
   290 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   291 the following package declarations:
   292 
   293   \usepackage[utf8]{inputenc}
   294   \usepackage{textcomp}
   295 
   296 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   297 a Unicode character is treated as a single symbol, not a sequence of
   298 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   299 contain symbols without further backslash escapes, Unicode can now be
   300 used here as well.  Recall that Symbol.explode in ML provides a
   301 consistent view on symbols, while raw explode (or String.explode)
   302 merely give a byte-oriented representation.
   303 
   304 * Theory loader: source files are primarily located via the master
   305 directory of each theory node (where the .thy file itself resides).
   306 The global load path is still partially available as legacy feature.
   307 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   308 explicit paths, relatively to the theory.
   309 
   310 * Special treatment of ML file names has been discontinued.
   311 Historically, optional extensions .ML or .sml were added on demand --
   312 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   313 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   314 
   315 * Various options that affect pretty printing etc. are now properly
   316 handled within the context via configuration options, instead of
   317 unsynchronized references or print modes.  There are both ML Config.T
   318 entities and Isar declaration attributes to access these.
   319 
   320   ML (Config.T)                 Isar (attribute)
   321 
   322   eta_contract                  eta_contract
   323   show_brackets                 show_brackets
   324   show_sorts                    show_sorts
   325   show_types                    show_types
   326   show_question_marks           show_question_marks
   327   show_consts                   show_consts
   328   show_abbrevs                  show_abbrevs
   329 
   330   Syntax.ast_trace              syntax_ast_trace
   331   Syntax.ast_stat               syntax_ast_stat
   332   Syntax.ambiguity_level        syntax_ambiguity_level
   333 
   334   Goal_Display.goals_limit      goals_limit
   335   Goal_Display.show_main_goal   show_main_goal
   336 
   337   Method.rule_trace             rule_trace
   338 
   339   Thy_Output.display            thy_output_display
   340   Thy_Output.quotes             thy_output_quotes
   341   Thy_Output.indent             thy_output_indent
   342   Thy_Output.source             thy_output_source
   343   Thy_Output.break              thy_output_break
   344 
   345 Note that corresponding "..._default" references in ML may only be
   346 changed globally at the ROOT session setup, but *not* within a theory.
   347 The option "show_abbrevs" supersedes the former print mode
   348 "no_abbrevs" with inverted meaning.
   349 
   350 * More systematic naming of some configuration options.
   351 INCOMPATIBILITY.
   352 
   353   trace_simp  ~>  simp_trace
   354   debug_simp  ~>  simp_debug
   355 
   356 * Support for real valued configuration options, using simplistic
   357 floating-point notation that coincides with the inner syntax for
   358 float_token.
   359 
   360 * Support for real valued preferences (with approximative PGIP type):
   361 front-ends need to accept "pgint" values in float notation.
   362 INCOMPATIBILITY.
   363 
   364 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   365 DejaVu Sans.
   366 
   367 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   368 
   369 
   370 *** Pure ***
   371 
   372 * Command 'type_synonym' (with single argument) replaces somewhat
   373 outdated 'types', which is still available as legacy feature for some
   374 time.
   375 
   376 * Command 'nonterminal' (with 'and' separated list of arguments)
   377 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   378 
   379 * Command 'notepad' replaces former 'example_proof' for
   380 experimentation in Isar without any result.  INCOMPATIBILITY.
   381 
   382 * Locale interpretation commands 'interpret' and 'sublocale' accept
   383 lists of equations to map definitions in a locale to appropriate
   384 entities in the context of the interpretation.  The 'interpretation'
   385 command already provided this functionality.
   386 
   387 * Diagnostic command 'print_dependencies' prints the locale instances
   388 that would be activated if the specified expression was interpreted in
   389 the current context.  Variant "print_dependencies!" assumes a context
   390 without interpretations.
   391 
   392 * Diagnostic command 'print_interps' prints interpretations in proofs
   393 in addition to interpretations in theories.
   394 
   395 * Discontinued obsolete 'global' and 'local' commands to manipulate
   396 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   397 Sign.root_path and Sign.local_path may be applied directly where this
   398 feature is still required for historical reasons.
   399 
   400 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   401 'definition' instead.
   402 
   403 * The "prems" fact, which refers to the accidental collection of
   404 foundational premises in the context, is now explicitly marked as
   405 legacy feature and will be discontinued soon.  Consider using "assms"
   406 of the head statement or reference facts by explicit names.
   407 
   408 * Document antiquotations @{class} and @{type} print classes and type
   409 constructors.
   410 
   411 * Document antiquotation @{file} checks file/directory entries within
   412 the local file system.
   413 
   414 
   415 *** HOL ***
   416 
   417 * Coercive subtyping: functions can be declared as coercions and type
   418 inference will add them as necessary upon input of a term.  Theory
   419 Complex_Main declares real :: nat => real and real :: int => real as
   420 coercions. A coercion function f is declared like this:
   421 
   422   declare [[coercion f]]
   423 
   424 To lift coercions through type constructors (e.g. from nat => real to
   425 nat list => real list), map functions can be declared, e.g.
   426 
   427   declare [[coercion_map map]]
   428 
   429 Currently coercion inference is activated only in theories including
   430 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   431 the configuration option "coercion_enabled", e.g. it can be enabled in
   432 other theories like this:
   433 
   434   declare [[coercion_enabled]]
   435 
   436 * Command 'partial_function' provides basic support for recursive
   437 function definitions over complete partial orders.  Concrete instances
   438 are provided for i) the option type, ii) tail recursion on arbitrary
   439 types, and iii) the heap monad of Imperative_HOL.  See
   440 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   441 for examples.
   442 
   443 * Function package: f.psimps rules are no longer implicitly declared
   444 as [simp].  INCOMPATIBILITY.
   445 
   446 * Datatype package: theorems generated for executable equality (class
   447 "eq") carry proper names and are treated as default code equations.
   448 
   449 * Inductive package: now offers command 'inductive_simps' to
   450 automatically derive instantiated and simplified equations for
   451 inductive predicates, similar to 'inductive_cases'.
   452 
   453 * Command 'enriched_type' allows to register properties of the
   454 functorial structure of types.
   455 
   456 * Improved infrastructure for term evaluation using code generator
   457 techniques, in particular static evaluation conversions.
   458 
   459 * Code generator: Scala (2.8 or higher) has been added to the target
   460 languages.
   461 
   462 * Code generator: globbing constant expressions "*" and "Theory.*"
   463 have been replaced by the more idiomatic "_" and "Theory._".
   464 INCOMPATIBILITY.
   465 
   466 * Code generator: export_code without explicit file declaration prints
   467 to standard output.  INCOMPATIBILITY.
   468 
   469 * Code generator: do not print function definitions for case
   470 combinators any longer.
   471 
   472 * Code generator: simplification with rules determined with
   473 src/Tools/Code/code_simp.ML and method "code_simp".
   474 
   475 * Code generator for records: more idiomatic representation of record
   476 types.  Warning: records are not covered by ancient SML code
   477 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   478 rep_datatype declaration helps to succeed then:
   479 
   480   record 'a foo = ...
   481   ...
   482   rep_datatype foo_ext ...
   483 
   484 * Records: logical foundation type for records does not carry a
   485 '_type' suffix any longer (obsolete due to authentic syntax).
   486 INCOMPATIBILITY.
   487 
   488 * Quickcheck now by default uses exhaustive testing instead of random
   489 testing.  Random testing can be invoked by "quickcheck [random]",
   490 exhaustive testing by "quickcheck [exhaustive]".
   491 
   492 * Quickcheck instantiates polymorphic types with small finite
   493 datatypes by default. This enables a simple execution mechanism to
   494 handle quantifiers and function equality over the finite datatypes.
   495 
   496 * Quickcheck random generator has been renamed from "code" to
   497 "random".  INCOMPATIBILITY.
   498 
   499 * Quickcheck now has a configurable time limit which is set to 30
   500 seconds by default. This can be changed by adding [timeout = n] to the
   501 quickcheck command. The time limit for Auto Quickcheck is still set
   502 independently.
   503 
   504 * Quickcheck in locales considers interpretations of that locale for
   505 counter example search.
   506 
   507 * Sledgehammer:
   508   - Added "smt" and "remote_smt" provers based on the "smt" proof
   509     method. See the Sledgehammer manual for details ("isabelle doc
   510     sledgehammer").
   511   - Renamed commands:
   512     sledgehammer atp_info ~> sledgehammer running_provers
   513     sledgehammer atp_kill ~> sledgehammer kill_provers
   514     sledgehammer available_atps ~> sledgehammer available_provers
   515     INCOMPATIBILITY.
   516   - Renamed options:
   517     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   518     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   519     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   520     (and "ms" and "min" are no longer supported)
   521     INCOMPATIBILITY.
   522 
   523 * Nitpick:
   524   - Renamed options:
   525     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   526     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   527     INCOMPATIBILITY.
   528   - Added support for partial quotient types.
   529   - Added local versions of the "Nitpick.register_xxx" functions.
   530   - Added "whack" option.
   531   - Allow registration of quotient types as codatatypes.
   532   - Improved "merge_type_vars" option to merge more types.
   533   - Removed unsound "fast_descrs" option.
   534   - Added custom symmetry breaking for datatypes, making it possible to reach
   535     higher cardinalities.
   536   - Prevent the expansion of too large definitions.
   537 
   538 * Proof methods "metis" and "meson" now have configuration options
   539 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   540 to diagnose these tools. E.g.
   541 
   542     using [[metis_trace = true]]
   543 
   544 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   545 manually as command 'solve_direct'.
   546 
   547 * The default SMT solver Z3 must be enabled explicitly (due to
   548 licensing issues) by setting the environment variable
   549 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   550 commercial applications, the SMT solver CVC3 is provided as fall-back;
   551 changing the SMT solver is done via the configuration option
   552 "smt_solver".
   553 
   554 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   555 i.e. "remote_cvc3" and "remote_z3".
   556 
   557 * Added basic SMT support for datatypes, records, and typedefs using
   558 the oracle mode (no proofs).  Direct support of pairs has been dropped
   559 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   560 support for a similar behavior).  Minor INCOMPATIBILITY.
   561 
   562 * Changed SMT configuration options:
   563   - Renamed:
   564     z3_proofs ~> smt_oracle (with inverted meaning)
   565     z3_trace_assms ~> smt_trace_used_facts
   566     INCOMPATIBILITY.
   567   - Added:
   568     smt_verbose
   569     smt_random_seed
   570     smt_datatypes
   571     smt_infer_triggers
   572     smt_monomorph_limit
   573     cvc3_options
   574     remote_cvc3_options
   575     remote_z3_options
   576     yices_options
   577 
   578 * Boogie output files (.b2i files) need to be declared in the theory
   579 header.
   580 
   581 * Simplification procedure "list_to_set_comprehension" rewrites list
   582 comprehensions applied to List.set to set comprehensions.  Occasional
   583 INCOMPATIBILITY, may be deactivated like this:
   584 
   585   declare [[simproc del: list_to_set_comprehension]]
   586 
   587 * Removed old version of primrec package.  INCOMPATIBILITY.
   588 
   589 * Removed simplifier congruence rule of "prod_case", as has for long
   590 been the case with "split".  INCOMPATIBILITY.
   591 
   592 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   593 
   594 * Removed [split_format ... and ... and ...] version of
   595 [split_format].  Potential INCOMPATIBILITY.
   596 
   597 * Predicate "sorted" now defined inductively, with nice induction
   598 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   599 
   600 * Constant "contents" renamed to "the_elem", to free the generic name
   601 contents for other uses.  INCOMPATIBILITY.
   602 
   603 * Renamed class eq and constant eq (for code generation) to class
   604 equal and constant equal, plus renaming of related facts and various
   605 tuning.  INCOMPATIBILITY.
   606 
   607 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   608 
   609 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   610 INCOMPATIBILITY.
   611 
   612 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   613 avoid confusion with finite sets.  INCOMPATIBILITY.
   614 
   615 * Abandoned locales equiv, congruent and congruent2 for equivalence
   616 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   617 for congruent(2)).
   618 
   619 * Some previously unqualified names have been qualified:
   620 
   621   types
   622     bool ~> HOL.bool
   623     nat ~> Nat.nat
   624 
   625   constants
   626     Trueprop ~> HOL.Trueprop
   627     True ~> HOL.True
   628     False ~> HOL.False
   629     op & ~> HOL.conj
   630     op | ~> HOL.disj
   631     op --> ~> HOL.implies
   632     op = ~> HOL.eq
   633     Not ~> HOL.Not
   634     The ~> HOL.The
   635     All ~> HOL.All
   636     Ex ~> HOL.Ex
   637     Ex1 ~> HOL.Ex1
   638     Let ~> HOL.Let
   639     If ~> HOL.If
   640     Ball ~> Set.Ball
   641     Bex ~> Set.Bex
   642     Suc ~> Nat.Suc
   643     Pair ~> Product_Type.Pair
   644     fst ~> Product_Type.fst
   645     snd ~> Product_Type.snd
   646     curry ~> Product_Type.curry
   647     op : ~> Set.member
   648     Collect ~> Set.Collect
   649 
   650 INCOMPATIBILITY.
   651 
   652 * More canonical naming convention for some fundamental definitions:
   653 
   654     bot_bool_eq ~> bot_bool_def
   655     top_bool_eq ~> top_bool_def
   656     inf_bool_eq ~> inf_bool_def
   657     sup_bool_eq ~> sup_bool_def
   658     bot_fun_eq  ~> bot_fun_def
   659     top_fun_eq  ~> top_fun_def
   660     inf_fun_eq  ~> inf_fun_def
   661     sup_fun_eq  ~> sup_fun_def
   662 
   663 INCOMPATIBILITY.
   664 
   665 * More stylized fact names:
   666 
   667   expand_fun_eq ~> fun_eq_iff
   668   expand_set_eq ~> set_eq_iff
   669   set_ext       ~> set_eqI
   670   nat_number    ~> eval_nat_numeral
   671 
   672 INCOMPATIBILITY.
   673 
   674 * Refactoring of code-generation specific operations in theory List:
   675 
   676   constants
   677     null ~> List.null
   678 
   679   facts
   680     mem_iff ~> member_def
   681     null_empty ~> null_def
   682 
   683 INCOMPATIBILITY.  Note that these were not supposed to be used
   684 regularly unless for striking reasons; their main purpose was code
   685 generation.
   686 
   687 Various operations from the Haskell prelude are used for generating
   688 Haskell code.
   689 
   690 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   691 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   692 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   693 
   694 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   695 "*" and "+" respectively.  INCOMPATIBILITY.
   696 
   697 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   698 "Sum_Type.Plus" instead.
   699 
   700 * Constant "split" has been merged with constant "prod_case"; names of
   701 ML functions, facts etc. involving split have been retained so far,
   702 though.  INCOMPATIBILITY.
   703 
   704 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   705 instead.  INCOMPATIBILITY.
   706 
   707 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   708 INCOMPATIBILITY.
   709 
   710 * Former theory Library/Enum is now part of the HOL-Main image.
   711 INCOMPATIBILITY: all constants of the Enum theory now have to be
   712 referred to by its qualified name.
   713 
   714   enum    ~>  Enum.enum
   715   nlists  ~>  Enum.nlists
   716   product ~>  Enum.product
   717 
   718 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   719 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   720 INCOMPATIBILITY.
   721 
   722 * Theory Library/SetsAndFunctions has been split into
   723 Library/Function_Algebras and Library/Set_Algebras; canonical names
   724 for instance definitions for functions; various improvements.
   725 INCOMPATIBILITY.
   726 
   727 * Theory Library/Multiset provides stable quicksort implementation of
   728 sort_key.
   729 
   730 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   731 INCOMPATIBILITY.
   732 
   733 * Session Multivariate_Analysis: introduced a type class for euclidean
   734 space.  Most theorems are now stated in terms of euclidean spaces
   735 instead of finite cartesian products.
   736 
   737   types
   738     real ^ 'n ~>  'a::real_vector
   739               ~>  'a::euclidean_space
   740               ~>  'a::ordered_euclidean_space
   741         (depends on your needs)
   742 
   743   constants
   744      _ $ _        ~> _ $$ _
   745      \<chi> x. _  ~> \<chi>\<chi> x. _
   746      CARD('n)     ~> DIM('a)
   747 
   748 Also note that the indices are now natural numbers and not from some
   749 finite type. Finite cartesian products of euclidean spaces, products
   750 of euclidean spaces the real and complex numbers are instantiated to
   751 be euclidean_spaces.  INCOMPATIBILITY.
   752 
   753 * Session Probability: introduced pextreal as positive extended real
   754 numbers.  Use pextreal as value for measures.  Introduce the
   755 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   756 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   757 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   758 
   759 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   760 INCOMPATIBILITY.
   761 
   762 * Session SPARK (with image HOL-SPARK) provides commands to load and
   763 prove verification conditions generated by the SPARK Ada program
   764 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   765 
   766 
   767 *** HOL-Algebra ***
   768 
   769 * Theorems for additive ring operations (locale abelian_monoid and
   770 descendants) are generated by interpretation from their multiplicative
   771 counterparts.  Names (in particular theorem names) have the mandatory
   772 qualifier 'add'.  Previous theorem names are redeclared for
   773 compatibility.
   774 
   775 * Structure "int_ring" is now an abbreviation (previously a
   776 definition).  This fits more natural with advanced interpretations.
   777 
   778 
   779 *** HOLCF ***
   780 
   781 * The domain package now runs in definitional mode by default: The
   782 former command 'new_domain' is now called 'domain'.  To use the domain
   783 package in its original axiomatic mode, use 'domain (unsafe)'.
   784 INCOMPATIBILITY.
   785 
   786 * The new class "domain" is now the default sort.  Class "predomain"
   787 is an unpointed version of "domain". Theories can be updated by
   788 replacing sort annotations as shown below.  INCOMPATIBILITY.
   789 
   790   'a::type ~> 'a::countable
   791   'a::cpo  ~> 'a::predomain
   792   'a::pcpo ~> 'a::domain
   793 
   794 * The old type class "rep" has been superseded by class "domain".
   795 Accordingly, users of the definitional package must remove any
   796 "default_sort rep" declarations.  INCOMPATIBILITY.
   797 
   798 * The domain package (definitional mode) now supports unpointed
   799 predomain argument types, as long as they are marked 'lazy'. (Strict
   800 arguments must be in class "domain".) For example, the following
   801 domain definition now works:
   802 
   803   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   804 
   805 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   806 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   807 'a option, and 'a list.  Additionally, it configures fixrec and the
   808 domain package to work with these types.  For example:
   809 
   810   fixrec isInl :: "('a + 'b) u -> tr"
   811     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   812 
   813   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   814 
   815 * The "(permissive)" option of fixrec has been replaced with a
   816 per-equation "(unchecked)" option. See
   817 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
   818 
   819 * The "bifinite" class no longer fixes a constant "approx"; the class
   820 now just asserts that such a function exists.  INCOMPATIBILITY.
   821 
   822 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
   823 defines an embedding of type 'a defl into udom by default; instances
   824 of "bifinite" and "domain" classes are available in
   825 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
   826 
   827 * The syntax "REP('a)" has been replaced with "DEFL('a)".
   828 
   829 * The predicate "directed" has been removed.  INCOMPATIBILITY.
   830 
   831 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
   832 
   833 * The function "cprod_map" has been renamed to "prod_map".
   834 INCOMPATIBILITY.
   835 
   836 * The monadic bind operator on each powerdomain has new binder syntax
   837 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
   838 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
   839 
   840 * The infix syntax for binary union on each powerdomain has changed
   841 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
   842 syntax.  INCOMPATIBILITY.
   843 
   844 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
   845 still supported as an input translation.
   846 
   847 * Renamed some theorems (the original names are also still available).
   848 
   849   expand_fun_below   ~> fun_below_iff
   850   below_fun_ext      ~> fun_belowI
   851   expand_cfun_eq     ~> cfun_eq_iff
   852   ext_cfun           ~> cfun_eqI
   853   expand_cfun_below  ~> cfun_below_iff
   854   below_cfun_ext     ~> cfun_belowI
   855   cont2cont_Rep_CFun ~> cont2cont_APP
   856 
   857 * The Abs and Rep functions for various types have changed names.
   858 Related theorem names have also changed to match. INCOMPATIBILITY.
   859 
   860   Rep_CFun  ~> Rep_cfun
   861   Abs_CFun  ~> Abs_cfun
   862   Rep_Sprod ~> Rep_sprod
   863   Abs_Sprod ~> Abs_sprod
   864   Rep_Ssum  ~> Rep_ssum
   865   Abs_Ssum  ~> Abs_ssum
   866 
   867 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   868 been renamed to *_bottom_iff.  INCOMPATIBILITY.
   869 
   870 * Various changes to bisimulation/coinduction with domain package:
   871 
   872   - Definitions of "bisim" constants no longer mention definedness.
   873   - With mutual recursion, "bisim" predicate is now curried.
   874   - With mutual recursion, each type gets a separate coind theorem.
   875   - Variable names in bisim_def and coinduct rules have changed.
   876 
   877 INCOMPATIBILITY.
   878 
   879 * Case combinators generated by the domain package for type "foo" are
   880 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
   881 
   882 * Several theorems have been renamed to more accurately reflect the
   883 names of constants and types involved.  INCOMPATIBILITY.
   884 
   885   thelub_const    ~> lub_const
   886   lub_const       ~> is_lub_const
   887   thelubI         ~> lub_eqI
   888   is_lub_lub      ~> is_lubD2
   889   lubI            ~> is_lub_lub
   890   unique_lub      ~> is_lub_unique
   891   is_ub_lub       ~> is_lub_rangeD1
   892   lub_bin_chain   ~> is_lub_bin_chain
   893   lub_fun         ~> is_lub_fun
   894   thelub_fun      ~> lub_fun
   895   thelub_cfun     ~> lub_cfun
   896   thelub_Pair     ~> lub_Pair
   897   lub_cprod       ~> is_lub_prod
   898   thelub_cprod    ~> lub_prod
   899   minimal_cprod   ~> minimal_prod
   900   inst_cprod_pcpo ~> inst_prod_pcpo
   901   UU_I            ~> bottomI
   902   compact_UU      ~> compact_bottom
   903   deflation_UU    ~> deflation_bottom
   904   finite_deflation_UU ~> finite_deflation_bottom
   905 
   906 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
   907 
   908   sq_ord_less_eq_trans ~> below_eq_trans
   909   sq_ord_eq_less_trans ~> eq_below_trans
   910   refl_less            ~> below_refl
   911   trans_less           ~> below_trans
   912   antisym_less         ~> below_antisym
   913   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
   914   box_less             ~> box_below
   915   rev_trans_less       ~> rev_below_trans
   916   not_less2not_eq      ~> not_below2not_eq
   917   less_UU_iff          ~> below_UU_iff
   918   flat_less_iff        ~> flat_below_iff
   919   adm_less             ~> adm_below
   920   adm_not_less         ~> adm_not_below
   921   adm_compact_not_less ~> adm_compact_not_below
   922   less_fun_def         ~> below_fun_def
   923   expand_fun_less      ~> fun_below_iff
   924   less_fun_ext         ~> fun_belowI
   925   less_discr_def       ~> below_discr_def
   926   discr_less_eq        ~> discr_below_eq
   927   less_unit_def        ~> below_unit_def
   928   less_cprod_def       ~> below_prod_def
   929   prod_lessI           ~> prod_belowI
   930   Pair_less_iff        ~> Pair_below_iff
   931   fst_less_iff         ~> fst_below_iff
   932   snd_less_iff         ~> snd_below_iff
   933   expand_cfun_less     ~> cfun_below_iff
   934   less_cfun_ext        ~> cfun_belowI
   935   injection_less       ~> injection_below
   936   less_up_def          ~> below_up_def
   937   not_Iup_less         ~> not_Iup_below
   938   Iup_less             ~> Iup_below
   939   up_less              ~> up_below
   940   Def_inject_less_eq   ~> Def_below_Def
   941   Def_less_is_eq       ~> Def_below_iff
   942   spair_less_iff       ~> spair_below_iff
   943   less_sprod           ~> below_sprod
   944   spair_less           ~> spair_below
   945   sfst_less_iff        ~> sfst_below_iff
   946   ssnd_less_iff        ~> ssnd_below_iff
   947   fix_least_less       ~> fix_least_below
   948   dist_less_one        ~> dist_below_one
   949   less_ONE             ~> below_ONE
   950   ONE_less_iff         ~> ONE_below_iff
   951   less_sinlD           ~> below_sinlD
   952   less_sinrD           ~> below_sinrD
   953 
   954 
   955 *** FOL and ZF ***
   956 
   957 * All constant names are now qualified internally and use proper
   958 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
   959 
   960 
   961 *** ML ***
   962 
   963 * Antiquotation @{assert} inlines a function bool -> unit that raises
   964 Fail if the argument is false.  Due to inlining the source position of
   965 failed assertions is included in the error output.
   966 
   967 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
   968 text is in practice always evaluated with a stable theory checkpoint.
   969 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
   970 
   971 * Antiquotation @{theory A} refers to theory A from the ancestry of
   972 the current context, not any accidental theory loader state as before.
   973 Potential INCOMPATIBILITY, subtle change in semantics.
   974 
   975 * Syntax.pretty_priority (default 0) configures the required priority
   976 of pretty-printed output and thus affects insertion of parentheses.
   977 
   978 * Syntax.default_root (default "any") configures the inner syntax
   979 category (nonterminal symbol) for parsing of terms.
   980 
   981 * Former exception Library.UnequalLengths now coincides with
   982 ListPair.UnequalLengths.
   983 
   984 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
   985 main functionality is provided by structure Simplifier.
   986 
   987 * Renamed raw "explode" function to "raw_explode" to emphasize its
   988 meaning.  Note that internally to Isabelle, Symbol.explode is used in
   989 almost all situations.
   990 
   991 * Discontinued obsolete function sys_error and exception SYS_ERROR.
   992 See implementation manual for further details on exceptions in
   993 Isabelle/ML.
   994 
   995 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   996 meaning.
   997 
   998 * Renamed structure PureThy to Pure_Thy and moved most of its
   999 operations to structure Global_Theory, to emphasize that this is
  1000 rarely-used global-only stuff.
  1001 
  1002 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
  1003 instead (or tracing for high-volume output).
  1004 
  1005 * Configuration option show_question_marks only affects regular pretty
  1006 printing of types and terms, not raw Term.string_of_vname.
  1007 
  1008 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
  1009 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
  1010 @{thms} for most purposes.
  1011 
  1012 * ML structure Unsynchronized is never opened, not even in Isar
  1013 interaction mode as before.  Old Unsynchronized.set etc. have been
  1014 discontinued -- use plain := instead.  This should be *rare* anyway,
  1015 since modern tools always work via official context data, notably
  1016 configuration options.
  1017 
  1018 * Parallel and asynchronous execution requires special care concerning
  1019 interrupts.  Structure Exn provides some convenience functions that
  1020 avoid working directly with raw Interrupt.  User code must not absorb
  1021 interrupts -- intermediate handling (for cleanup etc.) needs to be
  1022 followed by re-raising of the original exception.  Another common
  1023 source of mistakes are "handle _" patterns, which make the meaning of
  1024 the program subject to physical effects of the environment.
  1025 
  1026 
  1027 
  1028 New in Isabelle2009-2 (June 2010)
  1029 ---------------------------------
  1030 
  1031 *** General ***
  1032 
  1033 * Authentic syntax for *all* logical entities (type classes, type
  1034 constructors, term constants): provides simple and robust
  1035 correspondence between formal entities and concrete syntax.  Within
  1036 the parse tree / AST representations, "constants" are decorated by
  1037 their category (class, type, const) and spelled out explicitly with
  1038 their full internal name.
  1039 
  1040 Substantial INCOMPATIBILITY concerning low-level syntax declarations
  1041 and translations (translation rules and translation functions in ML).
  1042 Some hints on upgrading:
  1043 
  1044   - Many existing uses of 'syntax' and 'translations' can be replaced
  1045     by more modern 'type_notation', 'notation' and 'abbreviation',
  1046     which are independent of this issue.
  1047 
  1048   - 'translations' require markup within the AST; the term syntax
  1049     provides the following special forms:
  1050 
  1051       CONST c   -- produces syntax version of constant c from context
  1052       XCONST c  -- literally c, checked as constant from context
  1053       c         -- literally c, if declared by 'syntax'
  1054 
  1055     Plain identifiers are treated as AST variables -- occasionally the
  1056     system indicates accidental variables via the error "rhs contains
  1057     extra variables".
  1058 
  1059     Type classes and type constructors are marked according to their
  1060     concrete syntax.  Some old translations rules need to be written
  1061     for the "type" category, using type constructor application
  1062     instead of pseudo-term application of the default category
  1063     "logic".
  1064 
  1065   - 'parse_translation' etc. in ML may use the following
  1066     antiquotations:
  1067 
  1068       @{class_syntax c}   -- type class c within parse tree / AST
  1069       @{term_syntax c}    -- type constructor c within parse tree / AST
  1070       @{const_syntax c}   -- ML version of "CONST c" above
  1071       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
  1072 
  1073   - Literal types within 'typed_print_translations', i.e. those *not*
  1074     represented as pseudo-terms are represented verbatim.  Use @{class
  1075     c} or @{type_name c} here instead of the above syntax
  1076     antiquotations.
  1077 
  1078 Note that old non-authentic syntax was based on unqualified base
  1079 names, so all of the above "constant" names would coincide.  Recall
  1080 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
  1081 diagnose syntax problems.
  1082 
  1083 * Type constructors admit general mixfix syntax, not just infix.
  1084 
  1085 * Concrete syntax may be attached to local entities without a proof
  1086 body, too.  This works via regular mixfix annotations for 'fix',
  1087 'def', 'obtain' etc. or via the explicit 'write' command, which is
  1088 similar to the 'notation' command in theory specifications.
  1089 
  1090 * Discontinued unnamed infix syntax (legacy feature for many years) --
  1091 need to specify constant name and syntax separately.  Internal ML
  1092 datatype constructors have been renamed from InfixName to Infix etc.
  1093 Minor INCOMPATIBILITY.
  1094 
  1095 * Schematic theorem statements need to be explicitly markup as such,
  1096 via commands 'schematic_lemma', 'schematic_theorem',
  1097 'schematic_corollary'.  Thus the relevance of the proof is made
  1098 syntactically clear, which impacts performance in a parallel or
  1099 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  1100 
  1101 * Use of cumulative prems via "!" in some proof methods has been
  1102 discontinued (old legacy feature).
  1103 
  1104 * References 'trace_simp' and 'debug_simp' have been replaced by
  1105 configuration options stored in the context. Enabling tracing (the
  1106 case of debugging is similar) in proofs works via
  1107 
  1108   using [[trace_simp = true]]
  1109 
  1110 Tracing is then active for all invocations of the simplifier in
  1111 subsequent goal refinement steps. Tracing may also still be enabled or
  1112 disabled via the ProofGeneral settings menu.
  1113 
  1114 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  1115 'hide_fact' replace the former 'hide' KIND command.  Minor
  1116 INCOMPATIBILITY.
  1117 
  1118 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  1119 more efficient than combinations with -q1 or -q2.
  1120 
  1121 
  1122 *** Pure ***
  1123 
  1124 * Proofterms record type-class reasoning explicitly, using the
  1125 "unconstrain" operation internally.  This eliminates all sort
  1126 constraints from a theorem and proof, introducing explicit
  1127 OFCLASS-premises.  On the proof term level, this operation is
  1128 automatically applied at theorem boundaries, such that closed proofs
  1129 are always free of sort constraints.  INCOMPATIBILITY for tools that
  1130 inspect proof terms.
  1131 
  1132 * Local theory specifications may depend on extra type variables that
  1133 are not present in the result type -- arguments TYPE('a) :: 'a itself
  1134 are added internally.  For example:
  1135 
  1136   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  1137 
  1138 * Predicates of locales introduced by classes carry a mandatory
  1139 "class" prefix.  INCOMPATIBILITY.
  1140 
  1141 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  1142 
  1143 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  1144 'class' instead.
  1145 
  1146 * Command 'code_reflect' allows to incorporate generated ML code into
  1147 runtime environment; replaces immature code_datatype antiquotation.
  1148 INCOMPATIBILITY.
  1149 
  1150 * Code generator: simple concept for abstract datatypes obeying
  1151 invariants.
  1152 
  1153 * Code generator: details of internal data cache have no impact on the
  1154 user space functionality any longer.
  1155 
  1156 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1157 subgoals.  This is more appropriate for interpretations with 'where'.
  1158 INCOMPATIBILITY.
  1159 
  1160 * Command 'example_proof' opens an empty proof body.  This allows to
  1161 experiment with Isar, without producing any persistent result.
  1162 
  1163 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1164 within a local theory context, with explicit checking of the
  1165 constructors involved (in contrast to the raw 'syntax' versions).
  1166 
  1167 * Commands 'types' and 'typedecl' now work within a local theory
  1168 context -- without introducing dependencies on parameters or
  1169 assumptions, which is not possible in Isabelle/Pure.
  1170 
  1171 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1172 within a local theory context.  Minor INCOMPATIBILITY.
  1173 
  1174 
  1175 *** HOL ***
  1176 
  1177 * Command 'typedef' now works within a local theory context -- without
  1178 introducing dependencies on parameters or assumptions, which is not
  1179 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1180 contain multiple interpretations of local typedefs (with different
  1181 non-emptiness proofs), even in a global theory context.
  1182 
  1183 * New package for quotient types.  Commands 'quotient_type' and
  1184 'quotient_definition' may be used for defining types and constants by
  1185 quotient constructions.  An example is the type of integers created by
  1186 quotienting pairs of natural numbers:
  1187 
  1188   fun
  1189     intrel :: "(nat * nat) => (nat * nat) => bool"
  1190   where
  1191     "intrel (x, y) (u, v) = (x + v = u + y)"
  1192 
  1193   quotient_type int = "nat * nat" / intrel
  1194     by (auto simp add: equivp_def expand_fun_eq)
  1195 
  1196   quotient_definition
  1197     "0::int" is "(0::nat, 0::nat)"
  1198 
  1199 The method "lifting" can be used to lift of theorems from the
  1200 underlying "raw" type to the quotient type.  The example
  1201 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1202 construction and provides a reasoning infrastructure for finite sets.
  1203 
  1204 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1205 clash with new theory Quotient in Main HOL.
  1206 
  1207 * Moved the SMT binding into the main HOL session, eliminating
  1208 separate HOL-SMT session.
  1209 
  1210 * List membership infix mem operation is only an input abbreviation.
  1211 INCOMPATIBILITY.
  1212 
  1213 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1214 for future developements; former Library/Word.thy is still present in
  1215 the AFP entry RSAPPS.
  1216 
  1217 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1218 longer shadowed.  INCOMPATIBILITY.
  1219 
  1220 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1221 INCOMPATIBILITY.
  1222 
  1223 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1224 INCOMPATIBILITY.
  1225 
  1226 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1227 instead.  INCOMPATIBILITY.
  1228 
  1229 * Dropped several real-specific versions of lemmas about floor and
  1230 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1231 instead.  INCOMPATIBILITY.
  1232 
  1233   floor_number_of_eq         ~> floor_number_of
  1234   le_floor_eq_number_of      ~> number_of_le_floor
  1235   le_floor_eq_zero           ~> zero_le_floor
  1236   le_floor_eq_one            ~> one_le_floor
  1237   floor_less_eq_number_of    ~> floor_less_number_of
  1238   floor_less_eq_zero         ~> floor_less_zero
  1239   floor_less_eq_one          ~> floor_less_one
  1240   less_floor_eq_number_of    ~> number_of_less_floor
  1241   less_floor_eq_zero         ~> zero_less_floor
  1242   less_floor_eq_one          ~> one_less_floor
  1243   floor_le_eq_number_of      ~> floor_le_number_of
  1244   floor_le_eq_zero           ~> floor_le_zero
  1245   floor_le_eq_one            ~> floor_le_one
  1246   floor_subtract_number_of   ~> floor_diff_number_of
  1247   floor_subtract_one         ~> floor_diff_one
  1248   ceiling_number_of_eq       ~> ceiling_number_of
  1249   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1250   ceiling_le_zero_eq         ~> ceiling_le_zero
  1251   ceiling_le_eq_one          ~> ceiling_le_one
  1252   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1253   less_ceiling_eq_zero       ~> zero_less_ceiling
  1254   less_ceiling_eq_one        ~> one_less_ceiling
  1255   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1256   ceiling_less_eq_zero       ~> ceiling_less_zero
  1257   ceiling_less_eq_one        ~> ceiling_less_one
  1258   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1259   le_ceiling_eq_zero         ~> zero_le_ceiling
  1260   le_ceiling_eq_one          ~> one_le_ceiling
  1261   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1262   ceiling_subtract_one       ~> ceiling_diff_one
  1263 
  1264 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1265 application of the various fold combinators on finite sets.
  1266 
  1267 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1268 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1269 implementation.  INCOMPATIBILTY.
  1270 
  1271 * Theory Library/Coinductive_List has been removed -- superseded by
  1272 AFP/thys/Coinductive.
  1273 
  1274 * Theory PReal, including the type "preal" and related operations, has
  1275 been removed.  INCOMPATIBILITY.
  1276 
  1277 * Real: new development using Cauchy Sequences.
  1278 
  1279 * Split off theory "Big_Operators" containing setsum, setprod,
  1280 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1281 
  1282 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1283 "Int" etc.  INCOMPATIBILITY.
  1284 
  1285 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1286 
  1287 * New set of rules "ac_simps" provides combined assoc / commute
  1288 rewrites for all interpretations of the appropriate generic locales.
  1289 
  1290 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1291 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1292 appropriate and more consistent names suitable for name prefixes
  1293 within the HOL theories.  INCOMPATIBILITY.
  1294 
  1295 * Some generic constants have been put to appropriate theories:
  1296   - less_eq, less: Orderings
  1297   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1298   - inverse, divide: Rings
  1299 INCOMPATIBILITY.
  1300 
  1301 * More consistent naming of type classes involving orderings (and
  1302 lattices):
  1303 
  1304     lower_semilattice                   ~> semilattice_inf
  1305     upper_semilattice                   ~> semilattice_sup
  1306 
  1307     dense_linear_order                  ~> dense_linorder
  1308 
  1309     pordered_ab_group_add               ~> ordered_ab_group_add
  1310     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1311     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1312     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1313     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1314     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1315     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1316     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1317     pordered_comm_ring                  ~> ordered_comm_ring
  1318     pordered_comm_semiring              ~> ordered_comm_semiring
  1319     pordered_ring                       ~> ordered_ring
  1320     pordered_ring_abs                   ~> ordered_ring_abs
  1321     pordered_semiring                   ~> ordered_semiring
  1322 
  1323     ordered_ab_group_add                ~> linordered_ab_group_add
  1324     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1325     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1326     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1327     ordered_field                       ~> linordered_field
  1328     ordered_field_no_lb                 ~> linordered_field_no_lb
  1329     ordered_field_no_ub                 ~> linordered_field_no_ub
  1330     ordered_field_dense_linear_order    ~> dense_linordered_field
  1331     ordered_idom                        ~> linordered_idom
  1332     ordered_ring                        ~> linordered_ring
  1333     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1334     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1335     ordered_ring_strict                 ~> linordered_ring_strict
  1336     ordered_semidom                     ~> linordered_semidom
  1337     ordered_semiring                    ~> linordered_semiring
  1338     ordered_semiring_1                  ~> linordered_semiring_1
  1339     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1340     ordered_semiring_strict             ~> linordered_semiring_strict
  1341 
  1342   The following slightly odd type classes have been moved to a
  1343   separate theory Library/Lattice_Algebras:
  1344 
  1345     lordered_ab_group_add               ~> lattice_ab_group_add
  1346     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1347     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1348     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1349     lordered_ring                       ~> lattice_ring
  1350 
  1351 INCOMPATIBILITY.
  1352 
  1353 * Refined field classes:
  1354   - classes division_ring_inverse_zero, field_inverse_zero,
  1355     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1356     subsumes former division_by_zero class;
  1357   - numerous lemmas have been ported from field to division_ring.
  1358 INCOMPATIBILITY.
  1359 
  1360 * Refined algebra theorem collections:
  1361   - dropped theorem group group_simps, use algebra_simps instead;
  1362   - dropped theorem group ring_simps, use field_simps instead;
  1363   - proper theorem collection field_simps subsumes former theorem
  1364     groups field_eq_simps and field_simps;
  1365   - dropped lemma eq_minus_self_iff which is a duplicate for
  1366     equal_neg_zero.
  1367 INCOMPATIBILITY.
  1368 
  1369 * Theory Finite_Set and List: some lemmas have been generalized from
  1370 sets to lattices:
  1371 
  1372   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1373   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1374   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1375   union_Union_fold_union        ~> sup_Sup_fold_sup
  1376   Inter_fold_inter              ~> Inf_fold_inf
  1377   Union_fold_union              ~> Sup_fold_sup
  1378   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1379   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1380   INTER_fold_inter              ~> INFI_fold_inf
  1381   UNION_fold_union              ~> SUPR_fold_sup
  1382 
  1383 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1384 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1385 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1386 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1387 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1388 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1389 
  1390 * Reorganized theory Multiset: swapped notation of pointwise and
  1391 multiset order:
  1392 
  1393   - pointwise ordering is instance of class order with standard syntax
  1394     <= and <;
  1395   - multiset ordering has syntax <=# and <#; partial order properties
  1396     are provided by means of interpretation with prefix
  1397     multiset_order;
  1398   - less duplication, less historical organization of sections,
  1399     conversion from associations lists to multisets, rudimentary code
  1400     generation;
  1401   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1402     if needed.
  1403 
  1404 Renamed:
  1405 
  1406   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1407   multi_count_ext  ~>  multiset_ext
  1408   diff_union_inverse2  ~>  diff_union_cancelR
  1409 
  1410 INCOMPATIBILITY.
  1411 
  1412 * Theory Permutation: replaced local "remove" by List.remove1.
  1413 
  1414 * Code generation: ML and OCaml code is decorated with signatures.
  1415 
  1416 * Theory List: added transpose.
  1417 
  1418 * Library/Nat_Bijection.thy is a collection of bijective functions
  1419 between nat and other types, which supersedes the older libraries
  1420 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1421 
  1422   Constants:
  1423   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1424   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1425   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1426   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1427   Countable.pair_encode           ~> prod_encode
  1428   NatIso.prod2nat                 ~> prod_encode
  1429   NatIso.nat2prod                 ~> prod_decode
  1430   NatIso.sum2nat                  ~> sum_encode
  1431   NatIso.nat2sum                  ~> sum_decode
  1432   NatIso.list2nat                 ~> list_encode
  1433   NatIso.nat2list                 ~> list_decode
  1434   NatIso.set2nat                  ~> set_encode
  1435   NatIso.nat2set                  ~> set_decode
  1436 
  1437   Lemmas:
  1438   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1439   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1440   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1441   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1442   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1443   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1444   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1445   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1446   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1447   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1448   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1449   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1450   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1451 
  1452 * Sledgehammer:
  1453   - Renamed ATP commands:
  1454     atp_info     ~> sledgehammer running_atps
  1455     atp_kill     ~> sledgehammer kill_atps
  1456     atp_messages ~> sledgehammer messages
  1457     atp_minimize ~> sledgehammer minimize
  1458     print_atps   ~> sledgehammer available_atps
  1459     INCOMPATIBILITY.
  1460   - Added user's manual ("isabelle doc sledgehammer").
  1461   - Added option syntax and "sledgehammer_params" to customize
  1462     Sledgehammer's behavior.  See the manual for details.
  1463   - Modified the Isar proof reconstruction code so that it produces
  1464     direct proofs rather than proofs by contradiction.  (This feature
  1465     is still experimental.)
  1466   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1467     full-typed mode.
  1468   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1469 
  1470 * Nitpick:
  1471   - Added and implemented "binary_ints" and "bits" options.
  1472   - Added "std" option and implemented support for nonstandard models.
  1473   - Added and implemented "finitize" option to improve the precision
  1474     of infinite datatypes based on a monotonicity analysis.
  1475   - Added support for quotient types.
  1476   - Added support for "specification" and "ax_specification"
  1477     constructs.
  1478   - Added support for local definitions (for "function" and
  1479     "termination" proofs).
  1480   - Added support for term postprocessors.
  1481   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1482   - Improved efficiency of "destroy_constrs" optimization.
  1483   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1484     record getters.
  1485   - Fixed soundness bug related to higher-order constructors.
  1486   - Fixed soundness bug when "full_descrs" is enabled.
  1487   - Improved precision of set constructs.
  1488   - Added "atoms" option.
  1489   - Added cache to speed up repeated Kodkod invocations on the same
  1490     problems.
  1491   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1492     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1493     "SAT4J_Light".  INCOMPATIBILITY.
  1494   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1495     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1496   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1497 
  1498 * Method "induct" now takes instantiations of the form t, where t is not
  1499   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1500   If this is not intended, t has to be enclosed in parentheses.
  1501   By default, the equalities generated by definitional instantiations
  1502   are pre-simplified, which may cause parameters of inductive cases
  1503   to disappear, or may even delete some of the inductive cases.
  1504   Use "induct (no_simp)" instead of "induct" to restore the old
  1505   behaviour. The (no_simp) option is also understood by the "cases"
  1506   and "nominal_induct" methods, which now perform pre-simplification, too.
  1507   INCOMPATIBILITY.
  1508 
  1509 
  1510 *** HOLCF ***
  1511 
  1512 * Variable names in lemmas generated by the domain package have
  1513 changed; the naming scheme is now consistent with the HOL datatype
  1514 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1515 
  1516 * The domain package no longer defines the function "foo_copy" for
  1517 recursive domain "foo".  The reach lemma is now stated directly in
  1518 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1519 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1520 
  1521 * Most definedness lemmas generated by the domain package (previously
  1522 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1523 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1524 Proofs that used definedness lemmas as intro rules may break,
  1525 potential INCOMPATIBILITY.
  1526 
  1527 * Induction and casedist rules generated by the domain package now
  1528 declare proper case_names (one called "bottom", and one named for each
  1529 constructor).  INCOMPATIBILITY.
  1530 
  1531 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1532 rules are generated for each domain, INCOMPATIBILITY.
  1533 
  1534   foo_bar.reach       ~> foo.reach  bar.reach
  1535   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1536 
  1537 * Some lemmas generated by the domain package have been renamed for
  1538 consistency with the datatype package, INCOMPATIBILITY.
  1539 
  1540   foo.ind        ~> foo.induct
  1541   foo.finite_ind ~> foo.finite_induct
  1542   foo.coind      ~> foo.coinduct
  1543   foo.casedist   ~> foo.exhaust
  1544   foo.exhaust    ~> foo.nchotomy
  1545 
  1546 * For consistency with other definition packages, the fixrec package
  1547 now generates qualified theorem names, INCOMPATIBILITY.
  1548 
  1549   foo_simps  ~> foo.simps
  1550   foo_unfold ~> foo.unfold
  1551   foo_induct ~> foo.induct
  1552 
  1553 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1554 method and internal fixrec proofs now use the default simpset instead.
  1555 INCOMPATIBILITY.
  1556 
  1557 * The "contlub" predicate has been removed.  Proof scripts should use
  1558 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1559 
  1560 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1561 
  1562 * The constants cpair, cfst, and csnd have been removed in favor of
  1563 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1564 
  1565 
  1566 *** ML ***
  1567 
  1568 * Antiquotations for basic formal entities:
  1569 
  1570     @{class NAME}         -- type class
  1571     @{class_syntax NAME}  -- syntax representation of the above
  1572 
  1573     @{type_name NAME}     -- logical type
  1574     @{type_abbrev NAME}   -- type abbreviation
  1575     @{nonterminal NAME}   -- type of concrete syntactic category
  1576     @{type_syntax NAME}   -- syntax representation of any of the above
  1577 
  1578     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1579     @{const_abbrev NAME}  -- abbreviated constant
  1580     @{const_syntax NAME}  -- syntax representation of any of the above
  1581 
  1582 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1583 syntax constant (cf. 'syntax' command).
  1584 
  1585 * Antiquotation @{make_string} inlines a function to print arbitrary
  1586 values similar to the ML toplevel.  The result is compiler dependent
  1587 and may fall back on "?" in certain situations.
  1588 
  1589 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1590 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1591 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1592 not work with the asynchronous Isar document model.
  1593 
  1594 * Configuration options now admit dynamic default values, depending on
  1595 the context or even global references.
  1596 
  1597 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1598 uses an efficient external library if available (for Poly/ML).
  1599 
  1600 * Renamed some important ML structures, while keeping the old names
  1601 for some time as aliases within the structure Legacy:
  1602 
  1603   OuterKeyword  ~>  Keyword
  1604   OuterLex      ~>  Token
  1605   OuterParse    ~>  Parse
  1606   OuterSyntax   ~>  Outer_Syntax
  1607   PrintMode     ~>  Print_Mode
  1608   SpecParse     ~>  Parse_Spec
  1609   ThyInfo       ~>  Thy_Info
  1610   ThyLoad       ~>  Thy_Load
  1611   ThyOutput     ~>  Thy_Output
  1612   TypeInfer     ~>  Type_Infer
  1613 
  1614 Note that "open Legacy" simplifies porting of sources, but forgetting
  1615 to remove it again will complicate porting again in the future.
  1616 
  1617 * Most operations that refer to a global context are named
  1618 accordingly, e.g. Simplifier.global_context or
  1619 ProofContext.init_global.  There are some situations where a global
  1620 context actually works, but under normal circumstances one needs to
  1621 pass the proper local context through the code!
  1622 
  1623 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1624 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1625 Pretty.pp argument to merge, which is absent in the standard
  1626 Theory_Data version.
  1627 
  1628 * Sorts.certify_sort and derived "cert" operations for types and terms
  1629 no longer minimize sorts.  Thus certification at the boundary of the
  1630 inference kernel becomes invariant under addition of class relations,
  1631 which is an important monotonicity principle.  Sorts are now minimized
  1632 in the syntax layer only, at the boundary between the end-user and the
  1633 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1634 explicitly in rare situations.
  1635 
  1636 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1637 emphasize that this is in no way a standard operation.
  1638 INCOMPATIBILITY.
  1639 
  1640 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1641 usual for resolution.  Rare INCOMPATIBILITY.
  1642 
  1643 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1644 to emphasize that these only work in a global situation (which is
  1645 quite rare).
  1646 
  1647 * Curried take and drop in library.ML; negative length is interpreted
  1648 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1649 
  1650 * Proof terms: type substitutions on proof constants now use canonical
  1651 order of type variables.  INCOMPATIBILITY for tools working with proof
  1652 terms.
  1653 
  1654 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1655 may no longer carry premises.  User-level specifications are
  1656 transformed accordingly by Thm.add_axiom/add_def.
  1657 
  1658 
  1659 *** System ***
  1660 
  1661 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1662 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1663 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1664 
  1665 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1666 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1667 respectively.
  1668 
  1669 * Old lib/scripts/polyml-platform is superseded by the
  1670 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1671 variant, even on a 64 bit machine.  The following example setting
  1672 prefers 64 bit if available:
  1673 
  1674   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1675 
  1676 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1677 Isabelle/Scala layer for advanced prover interaction and integration.
  1678 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1679 component.
  1680 
  1681 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1682 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1683 similar to the default assignment of the document preparation system
  1684 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1685 provides some operations for direct access to the font without asking
  1686 the user for manual installation.
  1687 
  1688 
  1689 
  1690 New in Isabelle2009-1 (December 2009)
  1691 -------------------------------------
  1692 
  1693 *** General ***
  1694 
  1695 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1696 one backslash should be used, even in ML sources.
  1697 
  1698 
  1699 *** Pure ***
  1700 
  1701 * Locale interpretation propagates mixins along the locale hierarchy.
  1702 The currently only available mixins are the equations used to map
  1703 local definitions to terms of the target domain of an interpretation.
  1704 
  1705 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1706 loc" to print all interpretations of locale "loc" in the theory.
  1707 Interpretations in proofs are not shown.
  1708 
  1709 * Thoroughly revised locales tutorial.  New section on conditional
  1710 interpretation.
  1711 
  1712 * On instantiation of classes, remaining undefined class parameters
  1713 are formally declared.  INCOMPATIBILITY.
  1714 
  1715 
  1716 *** Document preparation ***
  1717 
  1718 * New generalized style concept for printing terms: @{foo (style) ...}
  1719 instead of @{foo_style style ...}  (old form is still retained for
  1720 backward compatibility).  Styles can be also applied for
  1721 antiquotations prop, term_type and typeof.
  1722 
  1723 
  1724 *** HOL ***
  1725 
  1726 * New proof method "smt" for a combination of first-order logic with
  1727 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1728 fixed-size bitvectors; there is also basic support for higher-order
  1729 features (esp. lambda abstractions).  It is an incomplete decision
  1730 procedure based on external SMT solvers using the oracle mechanism;
  1731 for the SMT solver Z3, this method is proof-producing.  Certificates
  1732 are provided to avoid calling the external solvers solely for
  1733 re-checking proofs.  Due to a remote SMT service there is no need for
  1734 installing SMT solvers locally.  See src/HOL/SMT.
  1735 
  1736 * New commands to load and prove verification conditions generated by
  1737 the Boogie program verifier or derived systems (e.g. the Verifying C
  1738 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1739 
  1740 * New counterexample generator tool 'nitpick' based on the Kodkod
  1741 relational model finder.  See src/HOL/Tools/Nitpick and
  1742 src/HOL/Nitpick_Examples.
  1743 
  1744 * New commands 'code_pred' and 'values' to invoke the predicate
  1745 compiler and to enumerate values of inductive predicates.
  1746 
  1747 * A tabled implementation of the reflexive transitive closure.
  1748 
  1749 * New implementation of quickcheck uses generic code generator;
  1750 default generators are provided for all suitable HOL types, records
  1751 and datatypes.  Old quickcheck can be re-activated importing theory
  1752 Library/SML_Quickcheck.
  1753 
  1754 * New testing tool Mirabelle for automated proof tools.  Applies
  1755 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1756 every proof step in a theory.  To be used in batch mode via the
  1757 "mirabelle" utility.
  1758 
  1759 * New proof method "sos" (sum of squares) for nonlinear real
  1760 arithmetic (originally due to John Harison). It requires theory
  1761 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1762 works well in practice on quantifier-free real arithmetic with +, -,
  1763 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1764 inequalities between polynomials.  It makes use of external
  1765 semidefinite programming solvers.  Method "sos" generates a
  1766 certificate that can be pasted into the proof thus avoiding the need
  1767 to call an external tool every time the proof is checked.  See
  1768 src/HOL/Library/Sum_Of_Squares.
  1769 
  1770 * New method "linarith" invokes existing linear arithmetic decision
  1771 procedure only.
  1772 
  1773 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1774 
  1775 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1776 Causes full type information to be output to the ATPs.  This slows
  1777 ATPs down considerably but eliminates a source of unsound "proofs"
  1778 that fail later.
  1779 
  1780 * New method "metisFT": A version of metis that uses full type
  1781 information in order to avoid failures of proof reconstruction.
  1782 
  1783 * New evaluator "approximate" approximates an real valued term using
  1784 the same method as the approximation method.
  1785 
  1786 * Method "approximate" now supports arithmetic expressions as
  1787 boundaries of intervals and implements interval splitting and Taylor
  1788 series expansion.
  1789 
  1790 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1791 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1792 
  1793 * New theory SupInf of the supremum and infimum operators for sets of
  1794 reals.
  1795 
  1796 * New theory Probability, which contains a development of measure
  1797 theory, eventually leading to Lebesgue integration and probability.
  1798 
  1799 * Extended Multivariate Analysis to include derivation and Brouwer's
  1800 fixpoint theorem.
  1801 
  1802 * Reorganization of number theory, INCOMPATIBILITY:
  1803   - new number theory development for nat and int, in theories Divides
  1804     and GCD as well as in new session Number_Theory
  1805   - some constants and facts now suffixed with _nat and _int
  1806     accordingly
  1807   - former session NumberTheory now named Old_Number_Theory, including
  1808     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1809   - moved theory Pocklington from src/HOL/Library to
  1810     src/HOL/Old_Number_Theory
  1811 
  1812 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1813 lcm of finite and infinite sets. It is shown that they form a complete
  1814 lattice.
  1815 
  1816 * Class semiring_div requires superclass no_zero_divisors and proof of
  1817 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1818 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1819 generalized to class semiring_div, subsuming former theorems
  1820 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1821 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1822 INCOMPATIBILITY.
  1823 
  1824 * Refinements to lattice classes and sets:
  1825   - less default intro/elim rules in locale variant, more default
  1826     intro/elim rules in class variant: more uniformity
  1827   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1828     le_inf_iff
  1829   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1830     sup_aci)
  1831   - renamed ACI to inf_sup_aci
  1832   - new class "boolean_algebra"
  1833   - class "complete_lattice" moved to separate theory
  1834     "Complete_Lattice"; corresponding constants (and abbreviations)
  1835     renamed and with authentic syntax:
  1836     Set.Inf ~>    Complete_Lattice.Inf
  1837     Set.Sup ~>    Complete_Lattice.Sup
  1838     Set.INFI ~>   Complete_Lattice.INFI
  1839     Set.SUPR ~>   Complete_Lattice.SUPR
  1840     Set.Inter ~>  Complete_Lattice.Inter
  1841     Set.Union ~>  Complete_Lattice.Union
  1842     Set.INTER ~>  Complete_Lattice.INTER
  1843     Set.UNION ~>  Complete_Lattice.UNION
  1844   - authentic syntax for
  1845     Set.Pow
  1846     Set.image
  1847   - mere abbreviations:
  1848     Set.empty               (for bot)
  1849     Set.UNIV                (for top)
  1850     Set.inter               (for inf, formerly Set.Int)
  1851     Set.union               (for sup, formerly Set.Un)
  1852     Complete_Lattice.Inter  (for Inf)
  1853     Complete_Lattice.Union  (for Sup)
  1854     Complete_Lattice.INTER  (for INFI)
  1855     Complete_Lattice.UNION  (for SUPR)
  1856   - object-logic definitions as far as appropriate
  1857 
  1858 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1859 Un_subset_iff are explicitly deleted as default simp rules; then also
  1860 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1861 deleted to achieve the desired effect.
  1862 
  1863 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1864 rules by default any longer; the same applies to min_max.inf_absorb1
  1865 etc.  INCOMPATIBILITY.
  1866 
  1867 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1868 pred_set_conv by default.  INCOMPATIBILITY.
  1869 
  1870 * Power operations on relations and functions are now one dedicated
  1871 constant "compow" with infix syntax "^^".  Power operation on
  1872 multiplicative monoids retains syntax "^" and is now defined generic
  1873 in class power.  INCOMPATIBILITY.
  1874 
  1875 * Relation composition "R O S" now has a more standard argument order:
  1876 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1877 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1878 break, since the O_assoc rule was not rewritten like this.  Fix using
  1879 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1880 
  1881 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1882 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1883 INCOMPATIBILITY.
  1884 
  1885 * Most rules produced by inductive and datatype package have mandatory
  1886 prefixes.  INCOMPATIBILITY.
  1887 
  1888 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1889 the attribute of the same name.  Each of the theorems in the list
  1890 DERIV_intros assumes composition with an additional function and
  1891 matches a variable to the derivative, which has to be solved by the
  1892 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1893 of most elementary terms.  Former Maclauren.DERIV_tac and
  1894 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1895 INCOMPATIBILITY.
  1896 
  1897 * Code generator attributes follow the usual underscore convention:
  1898     code_unfold     replaces    code unfold
  1899     code_post       replaces    code post
  1900     etc.
  1901   INCOMPATIBILITY.
  1902 
  1903 * Renamed methods:
  1904     sizechange -> size_change
  1905     induct_scheme -> induction_schema
  1906   INCOMPATIBILITY.
  1907 
  1908 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1909 INCOMPATIBILITY, use "undefined" directly.
  1910 
  1911 * Renamed theorems:
  1912     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1913     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1914     Suc_plus1 -> Suc_eq_plus1
  1915     *anti_sym -> *antisym*
  1916     vector_less_eq_def -> vector_le_def
  1917   INCOMPATIBILITY.
  1918 
  1919 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1920 INCOMPATIBILITY.
  1921 
  1922 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1923 INCOMPATIBILITY.
  1924 
  1925 
  1926 *** HOLCF ***
  1927 
  1928 * Theory Representable defines a class "rep" of domains that are
  1929 representable (via an ep-pair) in the universal domain type "udom".
  1930 Instances are provided for all type constructors defined in HOLCF.
  1931 
  1932 * The 'new_domain' command is a purely definitional version of the
  1933 domain package, for representable domains.  Syntax is identical to the
  1934 old domain package.  The 'new_domain' package also supports indirect
  1935 recursion using previously-defined type constructors.  See
  1936 src/HOLCF/ex/New_Domain.thy for examples.
  1937 
  1938 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1939 on the left-hand side of an equation, and then performs
  1940 simplification.  Rewriting is done using rules declared with the
  1941 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1942 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1943 
  1944 * The pattern-match compiler in 'fixrec' can now handle constructors
  1945 with HOL function types.  Pattern-match combinators for the Pair
  1946 constructor are pre-configured.
  1947 
  1948 * The 'fixrec' package now produces better fixed-point induction rules
  1949 for mutually-recursive definitions:  Induction rules have conclusions
  1950 of the form "P foo bar" instead of "P <foo, bar>".
  1951 
  1952 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1953 been renamed to "below".  The name "below" now replaces "less" in many
  1954 theorem names.  (Legacy theorem names using "less" are still supported
  1955 as well.)
  1956 
  1957 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1958 patterns can be used to generate strictness rules, or to make
  1959 functions more strict (much like the bang-patterns supported by the
  1960 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1961 examples.
  1962 
  1963 
  1964 *** ML ***
  1965 
  1966 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1967 errors and run-time exceptions, including detailed source positions.
  1968 
  1969 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1970 identified entries, with some additional information such as source
  1971 position, logical grouping etc.
  1972 
  1973 * Theory and context data is now introduced by the simplified and
  1974 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1975 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1976 copy operation) is still available for some time.
  1977 
  1978 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1979 provides a high-level programming interface to synchronized state
  1980 variables with atomic update.  This works via pure function
  1981 application within a critical section -- its runtime should be as
  1982 short as possible; beware of deadlocks if critical code is nested,
  1983 either directly or indirectly via other synchronized variables!
  1984 
  1985 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1986 wraps raw ML references, explicitly indicating their non-thread-safe
  1987 behaviour.  The Isar toplevel keeps this structure open, to
  1988 accommodate Proof General as well as quick and dirty interactive
  1989 experiments with references.
  1990 
  1991 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1992 parallel tactical reasoning.
  1993 
  1994 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1995 are similar to SUBPROOF, but are slightly more flexible: only the
  1996 specified parts of the subgoal are imported into the context, and the
  1997 body tactic may introduce new subgoals and schematic variables.
  1998 
  1999 * Old tactical METAHYPS, which does not observe the proof context, has
  2000 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  2001 or Subgoal.FOCUS etc.
  2002 
  2003 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  2004 functors have their own ML name space there is no point to mark them
  2005 separately.)  Minor INCOMPATIBILITY.
  2006 
  2007 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  2008 
  2009 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  2010 INCOMPATIBILITY.
  2011 
  2012 * Operations of structure Skip_Proof no longer require quick_and_dirty
  2013 mode, which avoids critical setmp.
  2014 
  2015 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  2016 combinators for "args".  INCOMPATIBILITY, need to use simplified
  2017 Attrib/Method.setup introduced in Isabelle2009.
  2018 
  2019 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  2020 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  2021 last resort.  INCOMPATIBILITY.
  2022 
  2023 * Display.pretty_thm now requires a proper context (cf. former
  2024 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  2025 or even Display.pretty_thm_without_context as last resort.
  2026 INCOMPATIBILITY.
  2027 
  2028 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  2029 Syntax.pretty_typ/term directly, preferably with proper context
  2030 instead of global theory.
  2031 
  2032 
  2033 *** System ***
  2034 
  2035 * Further fine tuning of parallel proof checking, scales up to 8 cores
  2036 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  2037 usedir option -q.
  2038 
  2039 * Support for additional "Isabelle components" via etc/components, see
  2040 also the system manual.
  2041 
  2042 * The isabelle makeall tool now operates on all components with
  2043 IsaMakefile, not just hardwired "logics".
  2044 
  2045 * Removed "compress" option from isabelle-process and isabelle usedir;
  2046 this is always enabled.
  2047 
  2048 * Discontinued support for Poly/ML 4.x versions.
  2049 
  2050 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  2051 on a given logic image.  This requires the lighttpd webserver and is
  2052 currently supported on Linux only.
  2053 
  2054 
  2055 
  2056 New in Isabelle2009 (April 2009)
  2057 --------------------------------
  2058 
  2059 *** General ***
  2060 
  2061 * Simplified main Isabelle executables, with less surprises on
  2062 case-insensitive file-systems (such as Mac OS).
  2063 
  2064   - The main Isabelle tool wrapper is now called "isabelle" instead of
  2065     "isatool."
  2066 
  2067   - The former "isabelle" alias for "isabelle-process" has been
  2068     removed (should rarely occur to regular users).
  2069 
  2070   - The former "isabelle-interface" and its alias "Isabelle" have been
  2071     removed (interfaces are now regular Isabelle tools).
  2072 
  2073 Within scripts and make files, the Isabelle environment variables
  2074 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  2075 respectively.  (The latter are still available as legacy feature.)
  2076 
  2077 The old isabelle-interface wrapper could react in confusing ways if
  2078 the interface was uninstalled or changed otherwise.  Individual
  2079 interface tool configuration is now more explicit, see also the
  2080 Isabelle system manual.  In particular, Proof General is now available
  2081 via "isabelle emacs".
  2082 
  2083 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  2084 purge installed copies of Isabelle executables and re-run "isabelle
  2085 install -p ...", or use symlinks.
  2086 
  2087 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  2088 old ~/isabelle, which was slightly non-standard and apt to cause
  2089 surprises on case-insensitive file-systems (such as Mac OS).
  2090 
  2091 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  2092 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  2093 care is required when using older releases of Isabelle.  Note that
  2094 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  2095 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  2096 
  2097 * Proofs of fully specified statements are run in parallel on
  2098 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  2099 a regular 4-core machine, if the initial heap space is made reasonably
  2100 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  2101 
  2102 * The main reference manuals ("isar-ref", "implementation", and
  2103 "system") have been updated and extended.  Formally checked references
  2104 as hyperlinks are now available uniformly.
  2105 
  2106 
  2107 *** Pure ***
  2108 
  2109 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  2110 respects.  The most important changes are listed below.  See the
  2111 Tutorial on Locales ("locales" manual) for details.
  2112 
  2113 - In locale expressions, instantiation replaces renaming.  Parameters
  2114 must be declared in a for clause.  To aid compatibility with previous
  2115 parameter inheritance, in locale declarations, parameters that are not
  2116 'touched' (instantiation position "_" or omitted) are implicitly added
  2117 with their syntax at the beginning of the for clause.
  2118 
  2119 - Syntax from abbreviations and definitions in locales is available in
  2120 locale expressions and context elements.  The latter is particularly
  2121 useful in locale declarations.
  2122 
  2123 - More flexible mechanisms to qualify names generated by locale
  2124 expressions.  Qualifiers (prefixes) may be specified in locale
  2125 expressions, and can be marked as mandatory (syntax: "name!:") or
  2126 optional (syntax "name?:").  The default depends for plain "name:"
  2127 depends on the situation where a locale expression is used: in
  2128 commands 'locale' and 'sublocale' prefixes are optional, in
  2129 'interpretation' and 'interpret' prefixes are mandatory.  The old
  2130 implicit qualifiers derived from the parameter names of a locale are
  2131 no longer generated.
  2132 
  2133 - Command "sublocale l < e" replaces "interpretation l < e".  The
  2134 instantiation clause in "interpretation" and "interpret" (square
  2135 brackets) is no longer available.  Use locale expressions.
  2136 
  2137 - When converting proof scripts, mandatory qualifiers in
  2138 'interpretation' and 'interpret' should be retained by default, even
  2139 if this is an INCOMPATIBILITY compared to former behavior.  In the
  2140 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  2141 in locale expressions range over a single locale instance only.
  2142 
  2143 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  2144 In existing theorem specifications replace the includes element by the
  2145 respective context elements of the included locale, omitting those
  2146 that are already present in the theorem specification.  Multiple
  2147 assume elements of a locale should be replaced by a single one
  2148 involving the locale predicate.  In the proof body, declarations (most
  2149 notably theorems) may be regained by interpreting the respective
  2150 locales in the proof context as required (command "interpret").
  2151 
  2152 If using "includes" in replacement of a target solely because the
  2153 parameter types in the theorem are not as general as in the target,
  2154 consider declaring a new locale with additional type constraints on
  2155 the parameters (context element "constrains").
  2156 
  2157 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2158 
  2159 - Locale interpretation commands no longer attempt to simplify goal.
  2160 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2161 methods intro_locales and unfold_locales to clarify.
  2162 
  2163 - Locale interpretation commands no longer accept interpretation
  2164 attributes.  INCOMPATIBILITY.
  2165 
  2166 * Class declaration: so-called "base sort" must not be given in import
  2167 list any longer, but is inferred from the specification.  Particularly
  2168 in HOL, write
  2169 
  2170     class foo = ...
  2171 
  2172 instead of
  2173 
  2174     class foo = type + ...
  2175 
  2176 * Class target: global versions of theorems stemming do not carry a
  2177 parameter prefix any longer.  INCOMPATIBILITY.
  2178 
  2179 * Class 'instance' command no longer accepts attached definitions.
  2180 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2181 
  2182 * Recovered hiding of consts, which was accidentally broken in
  2183 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2184 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2185 
  2186 * Slightly more coherent Pure syntax, with updated documentation in
  2187 isar-ref manual.  Removed locales meta_term_syntax and
  2188 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2189 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2190 directly in regular applications.
  2191 
  2192 * There is a new syntactic category "float_const" for signed decimal
  2193 fractions (e.g. 123.45 or -123.45).
  2194 
  2195 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2196 interface with 'setup' command instead.
  2197 
  2198 * Command 'local_setup' is similar to 'setup', but operates on a local
  2199 theory context.
  2200 
  2201 * The 'axiomatization' command now only works within a global theory
  2202 context.  INCOMPATIBILITY.
  2203 
  2204 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2205 hypotheses.  Sorts required in the course of reasoning need to be
  2206 covered by the constraints in the initial statement, completed by the
  2207 type instance information of the background theory.  Non-trivial sort
  2208 hypotheses, which rarely occur in practice, may be specified via
  2209 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2210 
  2211   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2212 
  2213 The result contains an implicit sort hypotheses as before --
  2214 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2215 normalization.
  2216 
  2217 * Generalized Isar history, with support for linear undo, direct state
  2218 addressing etc.
  2219 
  2220 * Changed defaults for unify configuration options:
  2221 
  2222   unify_trace_bound = 50 (formerly 25)
  2223   unify_search_bound = 60 (formerly 30)
  2224 
  2225 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2226 
  2227   a) On theory merge, the last set of code equations for a particular
  2228      constant is taken (in accordance with the policy applied by other
  2229      parts of the code generator framework).
  2230 
  2231   b) Code equations stemming from explicit declarations (e.g. code
  2232      attribute) gain priority over default code equations stemming
  2233      from definition, primrec, fun etc.
  2234 
  2235 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2236 
  2237 * Unified theorem tables for both code generators.  Thus [code
  2238 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2239 
  2240 * Command 'find_consts' searches for constants based on type and name
  2241 patterns, e.g.
  2242 
  2243     find_consts "_ => bool"
  2244 
  2245 By default, matching is against subtypes, but it may be restricted to
  2246 the whole type.  Searching by name is possible.  Multiple queries are
  2247 conjunctive and queries may be negated by prefixing them with a
  2248 hyphen:
  2249 
  2250     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2251 
  2252 * New 'find_theorems' criterion "solves" matches theorems that
  2253 directly solve the current goal (modulo higher-order unification).
  2254 
  2255 * Auto solve feature for main theorem statements: whenever a new goal
  2256 is stated, "find_theorems solves" is called; any theorems that could
  2257 solve the lemma directly are listed as part of the goal state.
  2258 Cf. associated options in Proof General Isabelle settings menu,
  2259 enabled by default, with reasonable timeout for pathological cases of
  2260 higher-order unification.
  2261 
  2262 
  2263 *** Document preparation ***
  2264 
  2265 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2266 demanding keyword 'by' and supporting the full method expression
  2267 syntax just like the Isar command 'by'.
  2268 
  2269 
  2270 *** HOL ***
  2271 
  2272 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2273 points Main and Complex_Main remain as before.
  2274 
  2275 * Logic image HOL-Plain provides a minimal HOL with the most important
  2276 tools available (inductive, datatype, primrec, ...).  This facilitates
  2277 experimentation and tool development.  Note that user applications
  2278 (and library theories) should never refer to anything below theory
  2279 Main, as before.
  2280 
  2281 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2282 experimentation due to shorter build times.
  2283 
  2284 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2285 were previously part of former HOL-Complex.  Entry point Hyperreal
  2286 remains valid, but theories formerly using Complex_Main should now use
  2287 new entry point Hypercomplex.
  2288 
  2289 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2290 Posix processes.  Avoids potentially expensive forking of the ML
  2291 process.  New thread-based implementation also works on non-Unix
  2292 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2293 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2294 commands are covered in the isar-ref manual.
  2295 
  2296 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2297 sledgehammer without local ATP installation (Vampire etc.). Other
  2298 provers may be included via suitable ML wrappers, see also
  2299 src/HOL/ATP_Linkup.thy.
  2300 
  2301 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2302 menu.
  2303 
  2304 * The metis method no longer fails because the theorem is too trivial
  2305 (contains the empty clause).
  2306 
  2307 * The metis method now fails in the usual manner, rather than raising
  2308 an exception, if it determines that it cannot prove the theorem.
  2309 
  2310 * Method "coherent" implements a prover for coherent logic (see also
  2311 src/Tools/coherent.ML).
  2312 
  2313 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2314 "undefined" is the right choice to replace "arbitrary", though
  2315 logically there is no difference.  INCOMPATIBILITY.
  2316 
  2317 * Command "value" now integrates different evaluation mechanisms.  The
  2318 result of the first successful evaluation mechanism is printed.  In
  2319 square brackets a particular named evaluation mechanisms may be
  2320 specified (currently, [SML], [code] or [nbe]).  See further
  2321 src/HOL/ex/Eval_Examples.thy.
  2322 
  2323 * Normalization by evaluation now allows non-leftlinear equations.
  2324 Declare with attribute [code nbe].
  2325 
  2326 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2327 as the structured Isar versions "cases" and "induct", cf. the
  2328 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2329 are now presented as a list of individual projections
  2330 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2331 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2332 rare situations a different rule is selected --- notably nested tuple
  2333 elimination instead of former prod.exhaust: use explicit (case_tac t
  2334 rule: prod.exhaust) here.
  2335 
  2336 * Attributes "cases", "induct", "coinduct" support "del" option.
  2337 
  2338 * Removed fact "case_split_thm", which duplicates "case_split".
  2339 
  2340 * The option datatype has been moved to a new theory Option.  Renamed
  2341 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2342 
  2343 * New predicate "strict_mono" classifies strict functions on partial
  2344 orders.  With strict functions on linear orders, reasoning about
  2345 (in)equalities is facilitated by theorems "strict_mono_eq",
  2346 "strict_mono_less_eq" and "strict_mono_less".
  2347 
  2348 * Some set operations are now proper qualified constants with
  2349 authentic syntax.  INCOMPATIBILITY:
  2350 
  2351     op Int ~>   Set.Int
  2352     op Un ~>    Set.Un
  2353     INTER ~>    Set.INTER
  2354     UNION ~>    Set.UNION
  2355     Inter ~>    Set.Inter
  2356     Union ~>    Set.Union
  2357     {} ~>       Set.empty
  2358     UNIV ~>     Set.UNIV
  2359 
  2360 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2361 theory Set.
  2362 
  2363 * Auxiliary class "itself" has disappeared -- classes without any
  2364 parameter are treated as expected by the 'class' command.
  2365 
  2366 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2367 
  2368 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2369 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2370 
  2371 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2372 method "approximation".  It proves formulas on real values by using
  2373 interval arithmetic.  In the formulas are also the transcendental
  2374 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2375 allowed. For examples see
  2376 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2377 
  2378 * Theory "Reflection" now resides in HOL/Library.
  2379 
  2380 * Entry point to Word library now simply named "Word".
  2381 INCOMPATIBILITY.
  2382 
  2383 * Made source layout more coherent with logical distribution
  2384 structure:
  2385 
  2386     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2387     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2388     src/HOL/Library/GCD.thy ~> src/HOL/
  2389     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2390     src/HOL/Library/Parity.thy ~> src/HOL/
  2391     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2392     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2393     src/HOL/Real/Lubs.thy ~> src/HOL/
  2394     src/HOL/Real/PReal.thy ~> src/HOL/
  2395     src/HOL/Real/Rational.thy ~> src/HOL/
  2396     src/HOL/Real/RComplete.thy ~> src/HOL/
  2397     src/HOL/Real/RealDef.thy ~> src/HOL/
  2398     src/HOL/Real/RealPow.thy ~> src/HOL/
  2399     src/HOL/Real/Real.thy ~> src/HOL/
  2400     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2401     src/HOL/Complex/Complex.thy ~> src/HOL/
  2402     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2403     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2404     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2405     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2406     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2407     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2408     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2409     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2410     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2411     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2412     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2413     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2414     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2415     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2416     src/HOL/Real/Float ~> src/HOL/Library/
  2417     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2418     src/HOL/Real/RealVector.thy ~> src/HOL/
  2419 
  2420     src/HOL/arith_data.ML ~> src/HOL/Tools
  2421     src/HOL/hologic.ML ~> src/HOL/Tools
  2422     src/HOL/simpdata.ML ~> src/HOL/Tools
  2423     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2424     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2425     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2426     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2427     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2428     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2429     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2430 
  2431     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2432     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2433     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2434     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2435     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2436     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2437 
  2438 * If methods "eval" and "evaluation" encounter a structured proof
  2439 state with !!/==>, only the conclusion is evaluated to True (if
  2440 possible), avoiding strange error messages.
  2441 
  2442 * Method "sizechange" automates termination proofs using (a
  2443 modification of) the size-change principle.  Requires SAT solver.  See
  2444 src/HOL/ex/Termination.thy for examples.
  2445 
  2446 * Simplifier: simproc for let expressions now unfolds if bound
  2447 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2448 
  2449 * Method "arith": Linear arithmetic now ignores all inequalities when
  2450 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2451 
  2452 * New attribute "arith" for facts that should always be used
  2453 automatically by arithmetic. It is intended to be used locally in
  2454 proofs, e.g.
  2455 
  2456   assumes [arith]: "x > 0"
  2457 
  2458 Global usage is discouraged because of possible performance impact.
  2459 
  2460 * New classes "top" and "bot" with corresponding operations "top" and
  2461 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2462 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2463 
  2464 * Changed definition lemma "less_fun_def" in order to provide an
  2465 instance for preorders on functions; use lemma "less_le" instead.
  2466 INCOMPATIBILITY.
  2467 
  2468 * Theory Orderings: class "wellorder" moved here, with explicit
  2469 induction rule "less_induct" as assumption.  For instantiation of
  2470 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2471 INCOMPATIBILITY.
  2472 
  2473 * Theory Orderings: added class "preorder" as superclass of "order".
  2474 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2475 etc. slightly changed.  Some theorems named order_class.* now named
  2476 preorder_class.*.
  2477 
  2478 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2479 "diag" to "Id_on".
  2480 
  2481 * Theory Finite_Set: added a new fold combinator of type
  2482 
  2483   ('a => 'b => 'b) => 'b => 'a set => 'b
  2484 
  2485 Occasionally this is more convenient than the old fold combinator
  2486 which is now defined in terms of the new one and renamed to
  2487 fold_image.
  2488 
  2489 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2490 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2491 extended with further lemmas!).  At the moment both still exist but
  2492 the former will disappear at some point.
  2493 
  2494 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2495 class recpower.  Type-specific simp rules for various recpower types
  2496 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2497 
  2498 rat_power_0    -> power_0
  2499 rat_power_Suc  -> power_Suc
  2500 realpow_0      -> power_0
  2501 realpow_Suc    -> power_Suc
  2502 complexpow_0   -> power_0
  2503 complexpow_Suc -> power_Suc
  2504 power_poly_0   -> power_0
  2505 power_poly_Suc -> power_Suc
  2506 
  2507 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2508 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2509 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2510 of lemmas from Divides has been generalized from nat to class
  2511 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2512 renames resulting from duplicate elimination:
  2513 
  2514     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2515     zero_dvd_iff ~>         dvd_0_left_iff
  2516     dvd_0 ~>                dvd_0_right
  2517     DIVISION_BY_ZERO_DIV ~> div_by_0
  2518     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2519     mult_div ~>             div_mult_self2_is_id
  2520     mult_mod ~>             mod_mult_self2_is_0
  2521 
  2522 * Theory IntDiv: removed many lemmas that are instances of class-based
  2523 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2524 rename old lemmas as follows:
  2525 
  2526 dvd_diff               -> nat_dvd_diff
  2527 dvd_zminus_iff         -> dvd_minus_iff
  2528 mod_add1_eq            -> mod_add_eq
  2529 mod_mult1_eq           -> mod_mult_right_eq
  2530 mod_mult1_eq'          -> mod_mult_left_eq
  2531 mod_mult_distrib_mod   -> mod_mult_eq
  2532 nat_mod_add_left_eq    -> mod_add_left_eq
  2533 nat_mod_add_right_eq   -> mod_add_right_eq
  2534 nat_mod_div_trivial    -> mod_div_trivial
  2535 nat_mod_mod_trivial    -> mod_mod_trivial
  2536 zdiv_zadd_self1        -> div_add_self1
  2537 zdiv_zadd_self2        -> div_add_self2
  2538 zdiv_zmult_self1       -> div_mult_self2_is_id
  2539 zdiv_zmult_self2       -> div_mult_self1_is_id
  2540 zdvd_triv_left         -> dvd_triv_left
  2541 zdvd_triv_right        -> dvd_triv_right
  2542 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2543 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2544 zmod_zadd_left_eq      -> mod_add_left_eq
  2545 zmod_zadd_right_eq     -> mod_add_right_eq
  2546 zmod_zadd_self1        -> mod_add_self1
  2547 zmod_zadd_self2        -> mod_add_self2
  2548 zmod_zadd1_eq          -> mod_add_eq
  2549 zmod_zdiff1_eq         -> mod_diff_eq
  2550 zmod_zdvd_zmod         -> mod_mod_cancel
  2551 zmod_zmod_cancel       -> mod_mod_cancel
  2552 zmod_zmult_self1       -> mod_mult_self2_is_0
  2553 zmod_zmult_self2       -> mod_mult_self1_is_0
  2554 zmod_1                 -> mod_by_1
  2555 zdiv_1                 -> div_by_1
  2556 zdvd_abs1              -> abs_dvd_iff
  2557 zdvd_abs2              -> dvd_abs_iff
  2558 zdvd_refl              -> dvd_refl
  2559 zdvd_trans             -> dvd_trans
  2560 zdvd_zadd              -> dvd_add
  2561 zdvd_zdiff             -> dvd_diff
  2562 zdvd_zminus_iff        -> dvd_minus_iff
  2563 zdvd_zminus2_iff       -> minus_dvd_iff
  2564 zdvd_zmultD            -> dvd_mult_right
  2565 zdvd_zmultD2           -> dvd_mult_left
  2566 zdvd_zmult_mono        -> mult_dvd_mono
  2567 zdvd_0_right           -> dvd_0_right
  2568 zdvd_0_left            -> dvd_0_left_iff
  2569 zdvd_1_left            -> one_dvd
  2570 zminus_dvd_iff         -> minus_dvd_iff
  2571 
  2572 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2573 
  2574 * The real numbers offer decimal input syntax: 12.34 is translated
  2575 into 1234/10^2. This translation is not reversed upon output.
  2576 
  2577 * Theory Library/Polynomial defines an abstract type 'a poly of
  2578 univariate polynomials with coefficients of type 'a.  In addition to
  2579 the standard ring operations, it also supports div and mod.  Code
  2580 generation is also supported, using list-style constructors.
  2581 
  2582 * Theory Library/Inner_Product defines a class of real_inner for real
  2583 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2584 => real.  Class real_inner is a subclass of real_normed_vector from
  2585 theory RealVector.
  2586 
  2587 * Theory Library/Product_Vector provides instances for the product
  2588 type 'a * 'b of several classes from RealVector and Inner_Product.
  2589 Definitions of addition, subtraction, scalar multiplication, norms,
  2590 and inner products are included.
  2591 
  2592 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2593 addition to the field operations, numerals and case syntax are also
  2594 supported.
  2595 
  2596 * Theory Library/Diagonalize provides constructive version of Cantor's
  2597 first diagonalization argument.
  2598 
  2599 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2600 zlcm (for int); carried together from various gcd/lcm developements in
  2601 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2602 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2603 may recover tupled syntax as follows:
  2604 
  2605     hide (open) const gcd
  2606     abbreviation gcd where
  2607       "gcd == (%(a, b). GCD.gcd a b)"
  2608     notation (output)
  2609       GCD.gcd ("gcd '(_, _')")
  2610 
  2611 The same works for lcm, zgcd, zlcm.
  2612 
  2613 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2614 instantiations for algebraic structures.  Removed some duplicate
  2615 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2616 
  2617 * ML antiquotation @{code} takes a constant as argument and generates
  2618 corresponding code in background and inserts name of the corresponding
  2619 resulting ML value/function/datatype constructor binding in place.
  2620 All occurrences of @{code} with a single ML block are generated
  2621 simultaneously.  Provides a generic and safe interface for
  2622 instrumentalizing code generation.  See
  2623 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2624 In future you ought to refrain from ad-hoc compiling generated SML
  2625 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2626 cannot refer to constants for which user-defined serializations are
  2627 set.  Refer to the corresponding ML counterpart directly in that
  2628 cases.
  2629 
  2630 * Command 'rep_datatype': instead of theorem names the command now
  2631 takes a list of terms denoting the constructors of the type to be
  2632 represented as datatype.  The characteristic theorems have to be
  2633 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2634 have disappeared in favour of existing ones:
  2635 
  2636     unit_induct                 ~> unit.induct
  2637     prod_induct                 ~> prod.induct
  2638     sum_induct                  ~> sum.induct
  2639     Suc_Suc_eq                  ~> nat.inject
  2640     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2641 
  2642 
  2643 *** HOL-Algebra ***
  2644 
  2645 * New locales for orders and lattices where the equivalence relation
  2646 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2647 locales use a record structure with field eq for the equivalence.
  2648 
  2649 * New theory of factorial domains.
  2650 
  2651 * Units_l_inv and Units_r_inv are now simp rules by default.
  2652 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2653 and/or r_inv will now also require deletion of these lemmas.
  2654 
  2655 * Renamed the following theorems, INCOMPATIBILITY:
  2656 
  2657 UpperD ~> Upper_memD
  2658 LowerD ~> Lower_memD
  2659 least_carrier ~> least_closed
  2660 greatest_carrier ~> greatest_closed
  2661 greatest_Lower_above ~> greatest_Lower_below
  2662 one_zero ~> carrier_one_zero
  2663 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2664 
  2665 
  2666 *** HOL-Nominal ***
  2667 
  2668 * Nominal datatypes can now contain type-variables.
  2669 
  2670 * Commands 'nominal_inductive' and 'equivariance' work with local
  2671 theory targets.
  2672 
  2673 * Nominal primrec can now works with local theory targets and its
  2674 specification syntax now conforms to the general format as seen in
  2675 'inductive' etc.
  2676 
  2677 * Method "perm_simp" honours the standard simplifier attributes
  2678 (no_asm), (no_asm_use) etc.
  2679 
  2680 * The new predicate #* is defined like freshness, except that on the
  2681 left hand side can be a set or list of atoms.
  2682 
  2683 * Experimental command 'nominal_inductive2' derives strong induction
  2684 principles for inductive definitions.  In contrast to
  2685 'nominal_inductive', which can only deal with a fixed number of
  2686 binders, it can deal with arbitrary expressions standing for sets of
  2687 atoms to be avoided.  The only inductive definition we have at the
  2688 moment that needs this generalisation is the typing rule for Lets in
  2689 the algorithm W:
  2690 
  2691  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2692  -----------------------------------------------------------------
  2693          Gamma |- Let x be t1 in t2 : T2
  2694 
  2695 In this rule one wants to avoid all the binders that are introduced by
  2696 "close Gamma T1".  We are looking for other examples where this
  2697 feature might be useful.  Please let us know.
  2698 
  2699 
  2700 *** HOLCF ***
  2701 
  2702 * Reimplemented the simplification procedure for proving continuity
  2703 subgoals.  The new simproc is extensible; users can declare additional
  2704 continuity introduction rules with the attribute [cont2cont].
  2705 
  2706 * The continuity simproc now uses a different introduction rule for
  2707 solving continuity subgoals on terms with lambda abstractions.  In
  2708 some rare cases the new simproc may fail to solve subgoals that the
  2709 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2710 Potential INCOMPATIBILITY.
  2711 
  2712 * Command 'fixrec': specification syntax now conforms to the general
  2713 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2714 examples.  INCOMPATIBILITY.
  2715 
  2716 
  2717 *** ZF ***
  2718 
  2719 * Proof of Zorn's Lemma for partial orders.
  2720 
  2721 
  2722 *** ML ***
  2723 
  2724 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2725 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2726 depends on multithreading, so timouts will not work before Poly/ML
  2727 5.2.1!
  2728 
  2729 * High-level support for concurrent ML programming, see
  2730 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2731 particularly convenient to organize independent functional
  2732 computations.  The concept of "synchronized variables" provides a
  2733 higher-order interface for components with shared state, avoiding the
  2734 delicate details of mutexes and condition variables.  (Requires
  2735 Poly/ML 5.2.1 or later.)
  2736 
  2737 * ML bindings produced via Isar commands are stored within the Isar
  2738 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2739 become thread-safe and work with undo as expected (concerning
  2740 top-level bindings, not side-effects on global references).
  2741 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2742 compiler at runtime; really global bindings need to be given outside a
  2743 theory.  (Requires Poly/ML 5.2 or later.)
  2744 
  2745 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2746 context.  Top-level ML bindings are stored within the proof context in
  2747 a purely sequential fashion, disregarding the nested proof structure.
  2748 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2749 proof.  (Requires Poly/ML 5.2 or later.)
  2750 
  2751 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2752 and Method.setup, as well as Isar commands 'attribute_setup' and
  2753 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2754 existing code accordingly, or use plain 'setup' together with old
  2755 Method.add_method.
  2756 
  2757 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2758 to 'a -> thm, while results are always tagged with an authentic oracle
  2759 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2760 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2761 accordingly.  Note that extra performance may be gained by producing
  2762 the cterm carefully, avoiding slow Thm.cterm_of.
  2763 
  2764 * Simplified interface for defining document antiquotations via
  2765 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2766 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2767 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2768 examples.
  2769 
  2770 * More systematic treatment of long names, abstract name bindings, and
  2771 name space operations.  Basic operations on qualified names have been
  2772 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2773 Long_Name.append.  Old type bstring has been mostly replaced by
  2774 abstract type binding (see structure Binding), which supports precise
  2775 qualification by packages and local theory targets, as well as proper
  2776 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2777 bstring values into Binding.name, or better pass through abstract
  2778 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2779 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2780 
  2781 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2782 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2783 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2784 
  2785 * Disposed old type and term read functions (Sign.read_def_typ,
  2786 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2787 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2788 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2789 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2790 resort for legacy applications.
  2791 
  2792 * Disposed old declarations, tactics, tactic combinators that refer to
  2793 the simpset or claset of an implicit theory (such as Addsimps,
  2794 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2795 embedded ML text, or local_simpset_of with a proper context passed as
  2796 explicit runtime argument.
  2797 
  2798 * Rules and tactics that read instantiations (read_instantiate,
  2799 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2800 context, which is required for parsing and type-checking.  Moreover,
  2801 the variables are specified as plain indexnames, not string encodings
  2802 thereof.  INCOMPATIBILITY.
  2803 
  2804 * Generic Toplevel.add_hook interface allows to analyze the result of
  2805 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2806 for theorem dependency output of transactions resulting in a new
  2807 theory state.
  2808 
  2809 * ML antiquotations: block-structured compilation context indicated by
  2810 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2811 
  2812   @{binding name}                         - basic name binding
  2813   @{let ?pat = term}                      - term abbreviation (HO matching)
  2814   @{note name = fact}                     - fact abbreviation
  2815   @{thm fact}                             - singleton fact (with attributes)
  2816   @{thms fact}                            - general fact (with attributes)
  2817   @{lemma prop by method}                 - singleton goal
  2818   @{lemma prop by meth1 meth2}            - singleton goal
  2819   @{lemma prop1 ... propN by method}      - general goal
  2820   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2821   @{lemma (open) ...}                     - open derivation
  2822 
  2823 
  2824 *** System ***
  2825 
  2826 * The Isabelle "emacs" tool provides a specific interface to invoke
  2827 Proof General / Emacs, with more explicit failure if that is not
  2828 installed (the old isabelle-interface script silently falls back on
  2829 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2830 installation location of the Proof General distribution.
  2831 
  2832 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2833 the Isabelle process into a JVM/Scala application.  See
  2834 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2835 process wrapper has been discontinued.)
  2836 
  2837 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2838 
  2839 * Various status messages (with exact source position information) are
  2840 emitted, if proper markup print mode is enabled.  This allows
  2841 user-interface components to provide detailed feedback on internal
  2842 prover operations.
  2843 
  2844 
  2845 
  2846 New in Isabelle2008 (June 2008)
  2847 -------------------------------
  2848 
  2849 *** General ***
  2850 
  2851 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2852 and updated, with formally checked references as hyperlinks.
  2853 
  2854 * Theory loader: use_thy (and similar operations) no longer set the
  2855 implicit ML context, which was occasionally hard to predict and in
  2856 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2857 provides a proper context already.
  2858 
  2859 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2860 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2861 'use' within a theory file will do the job.
  2862 
  2863 * Name space merge now observes canonical order, i.e. the second space
  2864 is inserted into the first one, while existing entries in the first
  2865 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2866 swap theory imports.
  2867 
  2868 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2869 INCOMPATIBILITY in identifier syntax etc.
  2870 
  2871 * Outer syntax: string tokens no longer admit escaped white space,
  2872 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2873 white space without escapes.
  2874 
  2875 * Outer syntax: string tokens may contain arbitrary character codes
  2876 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2877 "foo_bar".
  2878 
  2879 
  2880 *** Pure ***
  2881 
  2882 * Context-dependent token translations.  Default setup reverts locally
  2883 fixed variables, and adds hilite markup for undeclared frees.
  2884 
  2885 * Unused theorems can be found using the new command 'unused_thms'.
  2886 There are three ways of invoking it:
  2887 
  2888 (1) unused_thms
  2889      Only finds unused theorems in the current theory.
  2890 
  2891 (2) unused_thms thy_1 ... thy_n -
  2892      Finds unused theorems in the current theory and all of its ancestors,
  2893      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2894 
  2895 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2896      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2897      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2898      their ancestors.
  2899 
  2900 In order to increase the readability of the list produced by
  2901 unused_thms, theorems that have been created by a particular instance
  2902 of a theory command such as 'inductive' or 'function' are considered
  2903 to belong to the same "group", meaning that if at least one theorem in
  2904 this group is used, the other theorems in the same group are no longer
  2905 reported as unused.  Moreover, if all theorems in the group are
  2906 unused, only one theorem in the group is displayed.
  2907 
  2908 Note that proof objects have to be switched on in order for
  2909 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2910 usually the case when using Proof General with the default settings).
  2911 
  2912 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2913 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2914 duplicate fact bindings, or even accidental fact duplications.  Note
  2915 that tools may maintain dynamically scoped facts systematically, using
  2916 PureThy.add_thms_dynamic.
  2917 
  2918 * Command 'hide' now allows to hide from "fact" name space as well.
  2919 
  2920 * Eliminated destructive theorem database, simpset, claset, and
  2921 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2922 update of theories within ML code.
  2923 
  2924 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2925 INCOMPATIBILITY, object-logics depending on former Pure require
  2926 additional setup PureThy.old_appl_syntax_setup; object-logics
  2927 depending on former CPure need to refer to Pure.
  2928 
  2929 * Commands 'use' and 'ML' are now purely functional, operating on
  2930 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2931 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2932 INCOMPATIBILITY.
  2933 
  2934 * Command 'setup': discontinued implicit version with ML reference.
  2935 
  2936 * Instantiation target allows for simultaneous specification of class
  2937 instance operations together with an instantiation proof.
  2938 Type-checking phase allows to refer to class operations uniformly.
  2939 See src/HOL/Complex/Complex.thy for an Isar example and
  2940 src/HOL/Library/Eval.thy for an ML example.
  2941 
  2942 * Indexing of literal facts: be more serious about including only
  2943 facts from the visible specification/proof context, but not the
  2944 background context (locale etc.).  Affects `prop` notation and method
  2945 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2946 situations.
  2947 
  2948 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2949 "(open)" option, which used to expose internal bound variables to the
  2950 proof text.
  2951 
  2952 * Isar statements: removed obsolete case "rule_context".
  2953 INCOMPATIBILITY, better use explicit fixes/assumes.
  2954 
  2955 * Locale proofs: default proof step now includes 'unfold_locales';
  2956 hence 'proof' without argument may be used to unfold locale
  2957 predicates.
  2958 
  2959 
  2960 *** Document preparation ***
  2961 
  2962 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2963 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2964 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2965 spot); renamed link color from "darkblue" to "linkcolor" (default
  2966 value unchanged, can be redefined via \definecolor); no longer sets
  2967 "a4paper" option (unnecessary or even intrusive).
  2968 
  2969 * Antiquotation @{lemma A method} proves proposition A by the given
  2970 method (either a method name or a method name plus (optional) method
  2971 arguments in parentheses) and prints A just like @{prop A}.
  2972 
  2973 
  2974 *** HOL ***
  2975 
  2976 * New primrec package.  Specification syntax conforms in style to
  2977 definition/function/....  No separate induction rule is provided.  The
  2978 "primrec" command distinguishes old-style and new-style specifications
  2979 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2980 When adjusting theories, beware: constants stemming from new-style
  2981 primrec specifications have authentic syntax.
  2982 
  2983 * Metis prover is now an order of magnitude faster, and also works
  2984 with multithreading.
  2985 
  2986 * Metis: the maximum number of clauses that can be produced from a
  2987 theorem is now given by the attribute max_clauses.  Theorems that
  2988 exceed this number are ignored, with a warning printed.
  2989 
  2990 * Sledgehammer no longer produces structured proofs by default. To
  2991 enable, declare [[sledgehammer_full = true]].  Attributes
  2992 reconstruction_modulus, reconstruction_sorts renamed
  2993 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2994 
  2995 * Method "induct_scheme" derives user-specified induction rules
  2996 from well-founded induction and completeness of patterns. This factors
  2997 out some operations that are done internally by the function package
  2998 and makes them available separately.  See
  2999 src/HOL/ex/Induction_Scheme.thy for examples.
  3000 
  3001 * More flexible generation of measure functions for termination
  3002 proofs: Measure functions can be declared by proving a rule of the
  3003 form "is_measure f" and giving it the [measure_function] attribute.
  3004 The "is_measure" predicate is logically meaningless (always true), and
  3005 just guides the heuristic.  To find suitable measure functions, the
  3006 termination prover sets up the goal "is_measure ?f" of the appropriate
  3007 type and generates all solutions by prolog-style backwards proof using
  3008 the declared rules.
  3009 
  3010 This setup also deals with rules like 
  3011 
  3012   "is_measure f ==> is_measure (list_size f)"
  3013 
  3014 which accommodates nested datatypes that recurse through lists.
  3015 Similar rules are predeclared for products and option types.
  3016 
  3017 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  3018 
  3019   INCOMPATIBILITIES:
  3020 
  3021   - Definitions of overloaded constants on sets have to be replaced by
  3022     definitions on => and bool.
  3023 
  3024   - Some definitions of overloaded operators on sets can now be proved
  3025     using the definitions of the operators on => and bool.  Therefore,
  3026     the following theorems have been renamed:
  3027 
  3028       subset_def   -> subset_eq
  3029       psubset_def  -> psubset_eq
  3030       set_diff_def -> set_diff_eq
  3031       Compl_def    -> Compl_eq
  3032       Sup_set_def  -> Sup_set_eq
  3033       Inf_set_def  -> Inf_set_eq
  3034       sup_set_def  -> sup_set_eq
  3035       inf_set_def  -> inf_set_eq
  3036 
  3037   - Due to the incompleteness of the HO unification algorithm, some
  3038     rules such as subst may require manual instantiation, if some of
  3039     the unknowns in the rule is a set.
  3040 
  3041   - Higher order unification and forward proofs:
  3042     The proof pattern
  3043 
  3044       have "P (S::'a set)" <...>
  3045       then have "EX S. P S" ..
  3046 
  3047     no longer works (due to the incompleteness of the HO unification
  3048     algorithm) and must be replaced by the pattern
  3049 
  3050       have "EX S. P S"
  3051       proof
  3052         show "P S" <...>
  3053       qed
  3054 
  3055   - Calculational reasoning with subst (or similar rules):
  3056     The proof pattern
  3057 
  3058       have "P (S::'a set)" <...>
  3059       also have "S = T" <...>
  3060       finally have "P T" .
  3061 
  3062     no longer works (for similar reasons as the previous example) and
  3063     must be replaced by something like
  3064 
  3065       have "P (S::'a set)" <...>
  3066       moreover have "S = T" <...>
  3067       ultimately have "P T" by simp
  3068 
  3069   - Tactics or packages written in ML code:
  3070     Code performing pattern matching on types via
  3071 
  3072       Type ("set", [T]) => ...
  3073 
  3074     must be rewritten. Moreover, functions like strip_type or
  3075     binder_types no longer return the right value when applied to a
  3076     type of the form
  3077 
  3078       T1 => ... => Tn => U => bool
  3079 
  3080     rather than
  3081 
  3082       T1 => ... => Tn => U set
  3083 
  3084 * Merged theories Wellfounded_Recursion, Accessible_Part and
  3085 Wellfounded_Relations to theory Wellfounded.
  3086 
  3087 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  3088 
  3089 * Class finite no longer treats UNIV as class parameter.  Use class
  3090 enum from theory Library/Enum instead to achieve a similar effect.
  3091 INCOMPATIBILITY.
  3092 
  3093 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  3094 and "Cons".  INCOMPATIBILITY.
  3095 
  3096 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  3097 Potential INCOMPATIBILITY.
  3098 
  3099 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  3100 injective_fst_snd removed, use split_eta and prod_eqI instead.
  3101 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  3102 
  3103 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  3104 the same name in theory Orderings:
  3105 
  3106   less_trans
  3107   less_linear
  3108   le_imp_less_or_eq
  3109   le_less_trans
  3110   less_le_trans
  3111   less_not_sym
  3112   less_asym
  3113 
  3114 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  3115 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  3116 and different variable names.
  3117 
  3118 * Library/Option_ord.thy: Canonical order on option type.
  3119 
  3120 * Library/RBT.thy: Red-black trees, an efficient implementation of
  3121 finite maps.
  3122 
  3123 * Library/Countable.thy: Type class for countable types.
  3124 
  3125 * Theory Int: The representation of numerals has changed.  The infix
  3126 operator BIT and the bit datatype with constructors B0 and B1 have
  3127 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  3128 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  3129 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  3130 accordingly.
  3131 
  3132 * Theory Nat: definition of <= and < on natural numbers no longer
  3133 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  3134 le_def and less_def have disappeared.  Consider lemmas not_less
  3135 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  3136 
  3137 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  3138 (whose purpose mainly is for various fold_set functionals) have been
  3139 abandoned in favor of the existing algebraic classes
  3140 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  3141 lower_semilattice (resp. upper_semilattice) and linorder.
  3142 INCOMPATIBILITY.
  3143 
  3144 * Theory Transitive_Closure: induct and cases rules now declare proper
  3145 case_names ("base" and "step").  INCOMPATIBILITY.
  3146 
  3147 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  3148 lattices.  The form set-specific version is available as
  3149 Inductive.lfp_ordinal_induct_set.
  3150 
  3151 * Renamed theorems "power.simps" to "power_int.simps".
  3152 INCOMPATIBILITY.
  3153 
  3154 * Class semiring_div provides basic abstract properties of semirings
  3155 with division and modulo operations.  Subsumes former class dvd_mod.
  3156 
  3157 * Merged theories IntDef, Numeral and IntArith into unified theory
  3158 Int.  INCOMPATIBILITY.
  3159 
  3160 * Theory Library/Code_Index: type "index" now represents natural
  3161 numbers rather than integers.  INCOMPATIBILITY.
  3162 
  3163 * New class "uminus" with operation "uminus" (split of from class
  3164 "minus" which now only has operation "minus", binary).
  3165 INCOMPATIBILITY.
  3166 
  3167 * Constants "card", "internal_split", "option_map" now with authentic
  3168 syntax.  INCOMPATIBILITY.
  3169 
  3170 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3171 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3172 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3173 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3174 Sup_set_def, le_def, less_def, option_map_def now with object
  3175 equality.  INCOMPATIBILITY.
  3176 
  3177 * Records. Removed K_record, and replaced it by pure lambda term
  3178 %x. c. The simplifier setup is now more robust against eta expansion.
  3179 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3180 
  3181 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3182 
  3183 * Library/ListVector: new theory of arithmetic vector operations.
  3184 
  3185 * Library/Order_Relation: new theory of various orderings as sets of
  3186 pairs.  Defines preorders, partial orders, linear orders and
  3187 well-orders on sets and on types.
  3188 
  3189 
  3190 *** ZF ***
  3191 
  3192 * Renamed some theories to allow to loading both ZF and HOL in the
  3193 same session:
  3194 
  3195   Datatype  -> Datatype_ZF
  3196   Inductive -> Inductive_ZF
  3197   Int       -> Int_ZF
  3198   IntDiv    -> IntDiv_ZF
  3199   Nat       -> Nat_ZF
  3200   List      -> List_ZF
  3201   Main      -> Main_ZF
  3202 
  3203 INCOMPATIBILITY: ZF theories that import individual theories below
  3204 Main might need to be adapted.  Regular theory Main is still
  3205 available, as trivial extension of Main_ZF.
  3206 
  3207 
  3208 *** ML ***
  3209 
  3210 * ML within Isar: antiquotation @{const name} or @{const
  3211 name(typargs)} produces statically-checked Const term.
  3212 
  3213 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3214 (of the same name).  Removed obsolete print command.
  3215 
  3216 * Removed obsolete "use_legacy_bindings" function.
  3217 
  3218 * The ``print mode'' is now a thread-local value derived from a global
  3219 template (the former print_mode reference), thus access becomes
  3220 non-critical.  The global print_mode reference is for session
  3221 management only; user-code should use print_mode_value,
  3222 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3223 
  3224 * Functions system/system_out provide a robust way to invoke external
  3225 shell commands, with propagation of interrupts (requires Poly/ML
  3226 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3227 
  3228 
  3229 *** System ***
  3230 
  3231 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3232 in accordance with Proof General 3.7, which prefers GNU emacs.
  3233 
  3234 * isatool tty runs Isabelle process with plain tty interaction;
  3235 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3236 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3237 
  3238 * isatool browser now works with Cygwin as well, using general
  3239 "javapath" function defined in Isabelle process environment.
  3240 
  3241 * YXML notation provides a simple and efficient alternative to
  3242 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3243 isatool yxml as described in the Isabelle system manual.
  3244 
  3245 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3246 provides general wrapper for managing an Isabelle process in a robust
  3247 fashion, with ``cooked'' output from stdin/stderr.
  3248 
  3249 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3250 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3251 
  3252 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3253 way of changing the user's settings is via
  3254 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3255 script.
  3256 
  3257 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3258 cores of the underlying machine, which is a good starting point for
  3259 optimal performance tuning.  The corresponding usedir option -M allows
  3260 "max" as an alias for "0".  WARNING: does not work on certain versions
  3261 of Mac OS (with Poly/ML 5.1).
  3262 
  3263 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3264 adverse effect of Isabelle flooding interactive front-ends (notably
  3265 ProofGeneral / XEmacs).
  3266 
  3267 
  3268 
  3269 New in Isabelle2007 (November 2007)
  3270 -----------------------------------
  3271 
  3272 *** General ***
  3273 
  3274 * More uniform information about legacy features, notably a
  3275 warning/error of "Legacy feature: ...", depending on the state of the
  3276 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3277 legacy features will disappear eventually.
  3278 
  3279 * Theory syntax: the header format ``theory A = B + C:'' has been
  3280 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3281 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3282 
  3283 * Theory syntax: the old non-Isar theory file format has been
  3284 discontinued altogether.  Note that ML proof scripts may still be used
  3285 with Isar theories; migration is usually quite simple with the ML
  3286 function use_legacy_bindings.  INCOMPATIBILITY.
  3287 
  3288 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3289 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3290 quotes.
  3291 
  3292 * Theory loader: be more serious about observing the static theory
  3293 header specifications (including optional directories), but not the
  3294 accidental file locations of previously successful loads.  The strict
  3295 update policy of former update_thy is now already performed by
  3296 use_thy, so the former has been removed; use_thys updates several
  3297 theories simultaneously, just as 'imports' within a theory header
  3298 specification, but without merging the results.  Potential
  3299 INCOMPATIBILITY: may need to refine theory headers and commands
  3300 ROOT.ML which depend on load order.
  3301 
  3302 * Theory loader: optional support for content-based file
  3303 identification, instead of the traditional scheme of full physical
  3304 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3305 (cf. the system manual).  The new scheme allows to work with
  3306 non-finished theories in persistent session images, such that source
  3307 files may be moved later on without requiring reloads.
  3308 
  3309 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3310 file (with the same base name as the theory) are considered a legacy
  3311 feature, which will disappear eventually. Even now, the theory loader
  3312 no longer maintains dependencies on such files.
  3313 
  3314 * Syntax: the scope for resolving ambiguities via type-inference is
  3315 now limited to individual terms, instead of whole simultaneous
  3316 specifications as before. This greatly reduces the complexity of the
  3317 syntax module and improves flexibility by separating parsing and
  3318 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3319 'fixes' etc.) are required in rare situations.
  3320 
  3321 * Syntax: constants introduced by new-style packages ('definition',
  3322 'abbreviation' etc.) are passed through the syntax module in
  3323 ``authentic mode''. This means that associated mixfix annotations
  3324 really stick to such constants, independently of potential name space
  3325 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3326 trees are represented slightly differently, may need to adapt syntax
  3327 translations accordingly. Use CONST marker in 'translations' and
  3328 @{const_syntax} antiquotation in 'parse_translation' etc.
  3329 
  3330 * Legacy goal package: reduced interface to the bare minimum required
  3331 to keep existing proof scripts running.  Most other user-level
  3332 functions are now part of the OldGoals structure, which is *not* open
  3333 by default (consider isatool expandshort before open OldGoals).
  3334 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3335 these tend to cause confusion about the actual goal (!) context being
  3336 used here, which is not necessarily the same as the_context().
  3337 
  3338 * Command 'find_theorems': supports "*" wild-card in "name:"
  3339 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3340 support a specific search form (see ProofGeneral/CHANGES).
  3341 
  3342 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3343 by default, which means that "prems" (and also "fixed variables") are
  3344 suppressed from proof state output.  Note that the ProofGeneral
  3345 settings mechanism allows to change and save options persistently, but
  3346 older versions of Isabelle will fail to start up if a negative prems
  3347 limit is imposed.
  3348 
  3349 * Local theory targets may be specified by non-nested blocks of
  3350 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3351 contain definitions, theorems etc., including any derived mechanism
  3352 that has been implemented on top of these primitives.  This concept
  3353 generalizes the existing ``theorem (in ...)'' towards more versatility
  3354 and scalability.
  3355 
  3356 * Proof General interface: proper undo of final 'end' command;
  3357 discontinued Isabelle/classic mode (ML proof scripts).
  3358 
  3359 
  3360 *** Document preparation ***
  3361 
  3362 * Added antiquotation @{theory name} which prints the given name,
  3363 after checking that it refers to a valid ancestor theory in the
  3364 current context.
  3365 
  3366 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3367 check the given source text as ML type/structure, printing verbatim.
  3368 
  3369 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3370 "c args == rhs" given in the current context.  (Any number of
  3371 arguments may be given on the LHS.)
  3372 
  3373 
  3374 *** Pure ***
  3375 
  3376 * The 'class' package offers a combination of axclass and locale to
  3377 achieve Haskell-like type classes in Isabelle.  Definitions and
  3378 theorems within a class context produce both relative results (with
  3379 implicit parameters according to the locale context), and polymorphic
  3380 constants with qualified polymorphism (according to the class
  3381 context).  Within the body context of a 'class' target, a separate
  3382 syntax layer ("user space type system") takes care of converting
  3383 between global polymorphic consts and internal locale representation.
  3384 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3385 "isatool doc classes" provides a tutorial.
  3386 
  3387 * Generic code generator framework allows to generate executable
  3388 code for ML and Haskell (including Isabelle classes).  A short usage
  3389 sketch:
  3390 
  3391     internal compilation:
  3392         export_code <list of constants (term syntax)> in SML
  3393     writing SML code to a file:
  3394         export_code <list of constants (term syntax)> in SML <filename>
  3395     writing OCaml code to a file:
  3396         export_code <list of constants (term syntax)> in OCaml <filename>
  3397     writing Haskell code to a bunch of files:
  3398         export_code <list of constants (term syntax)> in Haskell <filename>
  3399 
  3400     evaluating closed propositions to True/False using code generation:
  3401         method ``eval''
  3402 
  3403 Reasonable default setup of framework in HOL.
  3404 
  3405 Theorem attributs for selecting and transforming function equations theorems:
  3406 
  3407     [code fun]:        select a theorem as function equation for a specific constant
  3408     [code fun del]:    deselect a theorem as function equation for a specific constant
  3409     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3410     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3411 
  3412 User-defined serializations (target in {SML, OCaml, Haskell}):
  3413 
  3414     code_const <and-list of constants (term syntax)>
  3415       {(target) <and-list of const target syntax>}+
  3416 
  3417     code_type <and-list of type constructors>
  3418       {(target) <and-list of type target syntax>}+
  3419 
  3420     code_instance <and-list of instances>
  3421       {(target)}+
  3422         where instance ::= <type constructor> :: <class>
  3423 
  3424     code_class <and_list of classes>
  3425       {(target) <and-list of class target syntax>}+
  3426         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3427 
  3428 code_instance and code_class only are effective to target Haskell.
  3429 
  3430 For example usage see src/HOL/ex/Codegenerator.thy and
  3431 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3432 generation from Isabelle/HOL theories is available via "isatool doc
  3433 codegen".
  3434 
  3435 * Code generator: consts in 'consts_code' Isar commands are now
  3436 referred to by usual term syntax (including optional type
  3437 annotations).
  3438 
  3439 * Command 'no_translations' removes translation rules from theory
  3440 syntax.
  3441 
  3442 * Overloaded definitions are now actually checked for acyclic
  3443 dependencies.  The overloading scheme is slightly more general than
  3444 that of Haskell98, although Isabelle does not demand an exact
  3445 correspondence to type class and instance declarations.
  3446 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3447 exotic versions of overloading -- at the discretion of the user!
  3448 
  3449 Polymorphic constants are represented via type arguments, i.e. the
  3450 instantiation that matches an instance against the most general
  3451 declaration given in the signature.  For example, with the declaration
  3452 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3453 as c(nat).  Overloading is essentially simultaneous structural
  3454 recursion over such type arguments.  Incomplete specification patterns
  3455 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3456 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3457 Command 'print_theory' outputs the normalized system of recursive
  3458 equations, see section "definitions".
  3459 
  3460 * Configuration options are maintained within the theory or proof
  3461 context (with name and type bool/int/string), providing a very simple
  3462 interface to a poor-man's version of general context data.  Tools may
  3463 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3464 these values using Config.get etc.  Users may change options via an
  3465 associated attribute of the same name.  This form of context
  3466 declaration works particularly well with commands 'declare' or
  3467 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3468 very easy to avoid global references, which would not observe Isar
  3469 toplevel undo/redo and fail to work with multithreading.
  3470 
  3471 Various global ML references of Pure and HOL have been turned into
  3472 configuration options:
  3473 
  3474   Unify.search_bound		unify_search_bound
  3475   Unify.trace_bound		unify_trace_bound
  3476   Unify.trace_simp		unify_trace_simp
  3477   Unify.trace_types		unify_trace_types
  3478   Simplifier.simp_depth_limit	simp_depth_limit
  3479   Blast.depth_limit		blast_depth_limit
  3480   DatatypeProp.dtK		datatype_distinctness_limit
  3481   fast_arith_neq_limit  	fast_arith_neq_limit
  3482   fast_arith_split_limit	fast_arith_split_limit
  3483 
  3484 * Named collections of theorems may be easily installed as context
  3485 data using the functor NamedThmsFun (see also
  3486 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3487 attributes; there is also a toplevel print command.  This facility is
  3488 just a common case of general context data, which is the preferred way
  3489 for anything more complex than just a list of facts in canonical
  3490 order.
  3491 
  3492 * Isar: command 'declaration' augments a local theory by generic
  3493 declaration functions written in ML.  This enables arbitrary content
  3494 being added to the context, depending on a morphism that tells the
  3495 difference of the original declaration context wrt. the application
  3496 context encountered later on.
  3497 
  3498 * Isar: proper interfaces for simplification procedures.  Command
  3499 'simproc_setup' declares named simprocs (with match patterns, and body
  3500 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3501 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3502 
  3503 * Isar: an extra pair of brackets around attribute declarations
  3504 abbreviates a theorem reference involving an internal dummy fact,
  3505 which will be ignored later --- only the effect of the attribute on
  3506 the background context will persist.  This form of in-place
  3507 declarations is particularly useful with commands like 'declare' and
  3508 'using', for example ``have A using [[simproc a]] by simp''.
  3509 
  3510 * Isar: method "assumption" (and implicit closing of subproofs) now
  3511 takes simple non-atomic goal assumptions into account: after applying
  3512 an assumption as a rule the resulting subgoals are solved by atomic
  3513 assumption steps.  This is particularly useful to finish 'obtain'
  3514 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3515 without referring to the original premise "!!x. P x ==> thesis" in the
  3516 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3517 more permissive.
  3518 
  3519 * Isar: implicit use of prems from the Isar proof context is
  3520 considered a legacy feature.  Common applications like ``have A .''
  3521 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3522 referencing facts explicitly here improves readability and
  3523 maintainability of proof texts.
  3524 
  3525 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3526 the obtained context from the course of reasoning!  For example:
  3527 
  3528   assume "EX x y. A x & B y"   -- "any previous fact"
  3529   then guess x and y by clarify
  3530 
  3531 This technique is potentially adventurous, depending on the facts and
  3532 proof tools being involved here.
  3533 
  3534 * Isar: known facts from the proof context may be specified as literal
  3535 propositions, using ASCII back-quote syntax.  This works wherever
  3536 named facts used to be allowed so far, in proof commands, proof
  3537 methods, attributes etc.  Literal facts are retrieved from the context
  3538 according to unification of type and term parameters.  For example,
  3539 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3540 theorems in the current context, then these are valid literal facts:
  3541 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3542 
  3543 There is also a proof method "fact" which does the same composition
  3544 for explicit goal states, e.g. the following proof texts coincide with
  3545 certain special cases of literal facts:
  3546 
  3547   have "A" by fact                 ==  note `A`
  3548   have "A ==> B" by fact           ==  note `A ==> B`
  3549   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3550   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3551 
  3552 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3553 outer syntax.  Thus symbolic identifiers may be used without
  3554 additional white space in declarations like this: ``assume *: A''.
  3555 
  3556 * Isar: 'print_facts' prints all local facts of the current context,
  3557 both named and unnamed ones.
  3558 
  3559 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3560 
  3561   def x == "t" and y == "u"
  3562 
  3563 * Isar: added command 'unfolding', which is structurally similar to
  3564 'using', but affects both the goal state and facts by unfolding given
  3565 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3566 'unfolded' attribute may be replaced by first-class proof text.
  3567 
  3568 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3569 and command 'unfolding' now all support object-level equalities
  3570 (potentially conditional).  The underlying notion of rewrite rule is
  3571 analogous to the 'rule_format' attribute, but *not* that of the
  3572 Simplifier (which is usually more generous).
  3573 
  3574 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3575 premises of a theorem by n. Useful in conjunction with drule.
  3576 
  3577 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3578 method expression within a sandbox consisting of the first N
  3579 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3580 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3581 simplifies all new goals that emerge from applying rule foo to the
  3582 originally first one.
  3583 
  3584 * Isar: schematic goals are no longer restricted to higher-order
  3585 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3586 expected.
  3587 
  3588 * Isar: the conclusion of a long theorem statement is now either
  3589 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3590 (essentially a disjunction of cases with local parameters and
  3591 assumptions).  The latter allows to express general elimination rules
  3592 adequately; in this notation common elimination rules look like this:
  3593 
  3594   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3595     assumes "EX x. P x"
  3596     obtains x where "P x"
  3597 
  3598   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3599     assumes "A & B"
  3600     obtains A and B
  3601 
  3602   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3603     assumes "A | B"
  3604     obtains
  3605       A
  3606     | B
  3607 
  3608 The subsequent classical rules even refer to the formal "thesis"
  3609 explicitly:
  3610 
  3611   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3612     obtains "~ thesis"
  3613 
  3614   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3615     obtains "thesis ==> something"
  3616 
  3617 The actual proof of an 'obtains' statement is analogous to that of the
  3618 Isar proof element 'obtain', only that there may be several cases.
  3619 Optional case names may be specified in parentheses; these will be
  3620 available both in the present proof and as annotations in the
  3621 resulting rule, for later use with the 'cases' method (cf. attribute
  3622 case_names).
  3623 
  3624 * Isar: the assumptions of a long theorem statement are available as
  3625 "assms" fact in the proof context.  This is more appropriate than the
  3626 (historical) "prems", which refers to all assumptions of the current
  3627 context, including those from the target locale, proof body etc.
  3628 
  3629 * Isar: 'print_statement' prints theorems from the current theory or
  3630 proof context in long statement form, according to the syntax of a
  3631 top-level lemma.
  3632 
  3633 * Isar: 'obtain' takes an optional case name for the local context
  3634 introduction rule (default "that").
  3635 
  3636 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3637 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3638 to occur.
  3639 
  3640 * Pure: syntax "CONST name" produces a fully internalized constant
  3641 according to the current context.  This is particularly useful for
  3642 syntax translations that should refer to internal constant
  3643 representations independently of name spaces.
  3644 
  3645 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3646 instead of "FOO ". This allows multiple binder declarations to coexist
  3647 in the same context.  INCOMPATIBILITY.
  3648 
  3649 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3650 primitive that also works in a locale context (both for constants and
  3651 fixed variables). Type declaration and internal syntactic representation
  3652 of given constants retrieved from the context. Likewise, the
  3653 'no_notation' command allows to remove given syntax annotations from the
  3654 current context.
  3655 
  3656 * Isar/locales: new derived specification elements 'axiomatization',
  3657 'definition', 'abbreviation', which support type-inference, admit
  3658 object-level specifications (equality, equivalence).  See also the
  3659 isar-ref manual.  Examples:
  3660 
  3661   axiomatization
  3662     eq  (infix "===" 50) where
  3663     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3664 
  3665   definition "f x y = x + y + 1"
  3666   definition g where "g x = f x x"
  3667 
  3668   abbreviation
  3669     neq  (infix "=!=" 50) where
  3670     "x =!= y == ~ (x === y)"
  3671 
  3672 These specifications may be also used in a locale context.  Then the
  3673 constants being introduced depend on certain fixed parameters, and the
  3674 constant name is qualified by the locale base name.  An internal
  3675 abbreviation takes care for convenient input and output, making the
  3676 parameters implicit and using the original short name.  See also
  3677 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3678 entities from a monomorphic theory.
  3679 
  3680 Presently, abbreviations are only available 'in' a target locale, but
  3681 not inherited by general import expressions.  Also note that
  3682 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3683 'translations' in common applications.  The "no_abbrevs" print mode
  3684 prevents folding of abbreviations in term output.
  3685 
  3686 Concrete syntax is attached to specified constants in internal form,
  3687 independently of name spaces.  The parse tree representation is
  3688 slightly different -- use 'notation' instead of raw 'syntax', and
  3689 'translations' with explicit "CONST" markup to accommodate this.
  3690 
  3691 * Pure/Isar: unified syntax for new-style specification mechanisms
  3692 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3693 full type inference and dummy patterns ("_").  For example:
  3694 
  3695   definition "K x _ = x"
  3696 
  3697   inductive conj for A B
  3698   where "A ==> B ==> conj A B"
  3699 
  3700 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3701 the current context.  Print mode "no_abbrevs" prevents inversion of
  3702 abbreviations on output.
  3703 
  3704 * Isar/locales: improved parameter handling: use of locales "var" and
  3705 "struct" no longer necessary; - parameter renamings are no longer
  3706 required to be injective.  For example, this allows to define
  3707 endomorphisms as locale endom = homom mult mult h.
  3708 
  3709 * Isar/locales: changed the way locales with predicates are defined.
  3710 Instead of accumulating the specification, the imported expression is
  3711 now an interpretation.  INCOMPATIBILITY: different normal form of
  3712 locale expressions.  In particular, in interpretations of locales with
  3713 predicates, goals repesenting already interpreted fragments are not
  3714 removed automatically.  Use methods `intro_locales' and
  3715 `unfold_locales'; see below.
  3716 
  3717 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3718 provide backward reasoning on locales predicates.  The methods are
  3719 aware of interpretations and discharge corresponding goals.
  3720 `intro_locales' is less aggressive then `unfold_locales' and does not
  3721 unfold predicates to assumptions.
  3722 
  3723 * Isar/locales: the order in which locale fragments are accumulated
  3724 has changed.  This enables to override declarations from fragments due
  3725 to interpretations -- for example, unwanted simp rules.
  3726 
  3727 * Isar/locales: interpretation in theories and proof contexts has been
  3728 extended.  One may now specify (and prove) equations, which are
  3729 unfolded in interpreted theorems.  This is useful for replacing
  3730 defined concepts (constants depending on locale parameters) by
  3731 concepts already existing in the target context.  Example:
  3732 
  3733   interpretation partial_order ["op <= :: [int, int] => bool"]
  3734     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3735 
  3736 Typically, the constant `partial_order.less' is created by a
  3737 definition specification element in the context of locale
  3738 partial_order.
  3739 
  3740 * Method "induct": improved internal context management to support
  3741 local fixes and defines on-the-fly. Thus explicit meta-level
  3742 connectives !!  and ==> are rarely required anymore in inductive goals
  3743 (using object-logic connectives for this purpose has been long
  3744 obsolete anyway). Common proof patterns are explained in
  3745 src/HOL/Induct/Common_Patterns.thy, see also
  3746 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3747 examples.
  3748 
  3749 * Method "induct": improved handling of simultaneous goals. Instead of
  3750 introducing object-level conjunction, the statement is now split into
  3751 several conclusions, while the corresponding symbolic cases are nested
  3752 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3753 see src/HOL/Induct/Common_Patterns.thy, for example.
  3754 
  3755 * Method "induct": mutual induction rules are now specified as a list
  3756 of rule sharing the same induction cases. HOL packages usually provide
  3757 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3758 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3759 mutual induction rules differently, i.e. like this:
  3760 
  3761   (induct rule: foo_bar.inducts)
  3762   (induct set: foo bar)
  3763   (induct pred: foo bar)
  3764   (induct type: foo bar)
  3765 
  3766 The ML function ProjectRule.projections turns old-style rules into the
  3767 new format.
  3768 
  3769 * Method "coinduct": dual of induction, see
  3770 src/HOL/Library/Coinductive_List.thy for various examples.
  3771 
  3772 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3773 considered a legacy feature.
  3774 
  3775 * Attribute "symmetric" produces result with standardized schematic
  3776 variables (index 0).  Potential INCOMPATIBILITY.
  3777 
  3778 * Simplifier: by default the simplifier trace only shows top level
  3779 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3780 default. Thus there is less danger of being flooded by the trace. The
  3781 trace indicates where parts have been suppressed.
  3782   
  3783 * Provers/classical: removed obsolete classical version of elim_format
  3784 attribute; classical elim/dest rules are now treated uniformly when
  3785 manipulating the claset.
  3786 
  3787 * Provers/classical: stricter checks to ensure that supplied intro,
  3788 dest and elim rules are well-formed; dest and elim rules must have at
  3789 least one premise.
  3790 
  3791 * Provers/classical: attributes dest/elim/intro take an optional
  3792 weight argument for the rule (just as the Pure versions).  Weights are
  3793 ignored by automated tools, but determine the search order of single
  3794 rule steps.
  3795 
  3796 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3797 where the body does not mention the bound variable.  Note that dummy
  3798 patterns implicitly depend on their context of bounds, which makes
  3799 "{_. _}" match any set comprehension as expected.  Potential
  3800 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3801 constant "_idtdummy" in the binding position.
  3802 
  3803 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3804 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3805 for example "A -> B" => "Pi A (%_. B)".
  3806 
  3807 * Pure: 'class_deps' command visualizes the subclass relation, using
  3808 the graph browser tool.
  3809 
  3810 * Pure: 'print_theory' now suppresses certain internal declarations by
  3811 default; use '!' option for full details.
  3812 
  3813 
  3814 *** HOL ***
  3815 
  3816 * Method "metis" proves goals by applying the Metis general-purpose
  3817 resolution prover (see also http://gilith.com/software/metis/).
  3818 Examples are in the directory MetisExamples.  WARNING: the
  3819 Isabelle/HOL-Metis integration does not yet work properly with
  3820 multi-threading.
  3821   
  3822 * Command 'sledgehammer' invokes external automatic theorem provers as
  3823 background processes.  It generates calls to the "metis" method if
  3824 successful. These can be pasted into the proof.  Users do not have to
  3825 wait for the automatic provers to return.  WARNING: does not really
  3826 work with multi-threading.
  3827 
  3828 * New "auto_quickcheck" feature tests outermost goal statements for
  3829 potential counter-examples.  Controlled by ML references
  3830 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3831 5000 milliseconds).  Fails silently if statements is outside of
  3832 executable fragment, or any other codgenerator problem occurs.
  3833 
  3834 * New constant "undefined" with axiom "undefined x = undefined".
  3835 
  3836 * Added class "HOL.eq", allowing for code generation with polymorphic
  3837 equality.
  3838 
  3839 * Some renaming of class constants due to canonical name prefixing in
  3840 the new 'class' package:
  3841 
  3842     HOL.abs ~> HOL.abs_class.abs
  3843     HOL.divide ~> HOL.divide_class.divide
  3844     0 ~> HOL.zero_class.zero
  3845     1 ~> HOL.one_class.one
  3846     op + ~> HOL.plus_class.plus
  3847     op - ~> HOL.minus_class.minus
  3848     uminus ~> HOL.minus_class.uminus
  3849     op * ~> HOL.times_class.times
  3850     op < ~> HOL.ord_class.less
  3851     op <= > HOL.ord_class.less_eq
  3852     Nat.power ~> Power.power_class.power
  3853     Nat.size ~> Nat.size_class.size
  3854     Numeral.number_of ~> Numeral.number_class.number_of
  3855     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3856     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3857     Orderings.min ~> Orderings.ord_class.min
  3858     Orderings.max ~> Orderings.ord_class.max
  3859     Divides.op div ~> Divides.div_class.div
  3860     Divides.op mod ~> Divides.div_class.mod
  3861     Divides.op dvd ~> Divides.div_class.dvd
  3862 
  3863 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3864 
  3865 a) User-defined constants using any of the names "plus", "minus",
  3866 "times", "less" or "less_eq". The standard syntax translations for
  3867 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3868 names.
  3869 
  3870 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3871 INCOMPATIBILITY: use more specific names.
  3872 
  3873 c) Permutative equations (e.g. "a + b = b + a")
  3874 Since the change of names also changes the order of terms, permutative
  3875 rewrite rules may get applied in a different order. Experience shows
  3876 that this is rarely the case (only two adaptions in the whole Isabelle
  3877 distribution).  INCOMPATIBILITY: rewrite proofs
  3878 
  3879 d) ML code directly refering to constant names
  3880 This in general only affects hand-written proof tactics, simprocs and
  3881 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3882 Consider using @{const_name} antiquotation.
  3883 
  3884 * New class "default" with associated constant "default".
  3885 
  3886 * Function "sgn" is now overloaded and available on int, real, complex
  3887 (and other numeric types), using class "sgn".  Two possible defs of
  3888 sgn are given as equational assumptions in the classes sgn_if and
  3889 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3890 INCOMPATIBILITY.
  3891 
  3892 * Locale "partial_order" now unified with class "order" (cf. theory
  3893 Orderings), added parameter "less".  INCOMPATIBILITY.
  3894 
  3895 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3896 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3897 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3898 
  3899 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3900 changed order of proof goals in instance proofs.
  3901 
  3902 * The transitivity reasoner for partial and linear orders is set up
  3903 for classes "order" and "linorder".  Instances of the reasoner are available
  3904 in all contexts importing or interpreting the corresponding locales.
  3905 Method "order" invokes the reasoner separately; the reasoner
  3906 is also integrated with the Simplifier as a solver.  Diagnostic
  3907 command 'print_orders' shows the available instances of the reasoner
  3908 in the current context.
  3909 
  3910 * Localized monotonicity predicate in theory "Orderings"; integrated
  3911 lemmas max_of_mono and min_of_mono with this predicate.
  3912 INCOMPATIBILITY.
  3913 
  3914 * Formulation of theorem "dense" changed slightly due to integration
  3915 with new class dense_linear_order.
  3916 
  3917 * Uniform lattice theory development in HOL.
  3918 
  3919     constants "meet" and "join" now named "inf" and "sup"
  3920     constant "Meet" now named "Inf"
  3921 
  3922     classes "meet_semilorder" and "join_semilorder" now named
  3923       "lower_semilattice" and "upper_semilattice"
  3924     class "lorder" now named "lattice"
  3925     class "comp_lat" now named "complete_lattice"
  3926 
  3927     Instantiation of lattice classes allows explicit definitions
  3928     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3929 
  3930   INCOMPATIBILITY.  Theorem renames:
  3931 
  3932     meet_left_le            ~> inf_le1
  3933     meet_right_le           ~> inf_le2
  3934     join_left_le            ~> sup_ge1
  3935     join_right_le           ~> sup_ge2
  3936     meet_join_le            ~> inf_sup_ord
  3937     le_meetI                ~> le_infI
  3938     join_leI                ~> le_supI
  3939     le_meet                 ~> le_inf_iff
  3940     le_join                 ~> ge_sup_conv
  3941     meet_idempotent         ~> inf_idem
  3942     join_idempotent         ~> sup_idem
  3943     meet_comm               ~> inf_commute
  3944     join_comm               ~> sup_commute
  3945     meet_leI1               ~> le_infI1
  3946     meet_leI2               ~> le_infI2
  3947     le_joinI1               ~> le_supI1
  3948     le_joinI2               ~> le_supI2
  3949     meet_assoc              ~> inf_assoc
  3950     join_assoc              ~> sup_assoc
  3951     meet_left_comm          ~> inf_left_commute
  3952     meet_left_idempotent    ~> inf_left_idem
  3953     join_left_comm          ~> sup_left_commute
  3954     join_left_idempotent    ~> sup_left_idem
  3955     meet_aci                ~> inf_aci
  3956     join_aci                ~> sup_aci
  3957     le_def_meet             ~> le_iff_inf
  3958     le_def_join             ~> le_iff_sup
  3959     join_absorp2            ~> sup_absorb2
  3960     join_absorp1            ~> sup_absorb1
  3961     meet_absorp1            ~> inf_absorb1
  3962     meet_absorp2            ~> inf_absorb2
  3963     meet_join_absorp        ~> inf_sup_absorb
  3964     join_meet_absorp        ~> sup_inf_absorb
  3965     distrib_join_le         ~> distrib_sup_le
  3966     distrib_meet_le         ~> distrib_inf_le
  3967 
  3968     add_meet_distrib_left   ~> add_inf_distrib_left
  3969     add_join_distrib_left   ~> add_sup_distrib_left
  3970     is_join_neg_meet        ~> is_join_neg_inf
  3971     is_meet_neg_join        ~> is_meet_neg_sup
  3972     add_meet_distrib_right  ~> add_inf_distrib_right
  3973     add_join_distrib_right  ~> add_sup_distrib_right
  3974     add_meet_join_distribs  ~> add_sup_inf_distribs
  3975     join_eq_neg_meet        ~> sup_eq_neg_inf
  3976     meet_eq_neg_join        ~> inf_eq_neg_sup
  3977     add_eq_meet_join        ~> add_eq_inf_sup
  3978     meet_0_imp_0            ~> inf_0_imp_0
  3979     join_0_imp_0            ~> sup_0_imp_0
  3980     meet_0_eq_0             ~> inf_0_eq_0
  3981     join_0_eq_0             ~> sup_0_eq_0
  3982     neg_meet_eq_join        ~> neg_inf_eq_sup
  3983     neg_join_eq_meet        ~> neg_sup_eq_inf
  3984     join_eq_if              ~> sup_eq_if
  3985 
  3986     mono_meet               ~> mono_inf
  3987     mono_join               ~> mono_sup
  3988     meet_bool_eq            ~> inf_bool_eq
  3989     join_bool_eq            ~> sup_bool_eq
  3990     meet_fun_eq             ~> inf_fun_eq
  3991     join_fun_eq             ~> sup_fun_eq
  3992     meet_set_eq             ~> inf_set_eq
  3993     join_set_eq             ~> sup_set_eq
  3994     meet1_iff               ~> inf1_iff
  3995     meet2_iff               ~> inf2_iff
  3996     meet1I                  ~> inf1I
  3997     meet2I                  ~> inf2I
  3998     meet1D1                 ~> inf1D1
  3999     meet2D1                 ~> inf2D1
  4000     meet1D2                 ~> inf1D2
  4001     meet2D2                 ~> inf2D2
  4002     meet1E                  ~> inf1E
  4003     meet2E                  ~> inf2E
  4004     join1_iff               ~> sup1_iff
  4005     join2_iff               ~> sup2_iff
  4006     join1I1                 ~> sup1I1
  4007     join2I1                 ~> sup2I1
  4008     join1I1                 ~> sup1I1
  4009     join2I2                 ~> sup1I2
  4010     join1CI                 ~> sup1CI
  4011     join2CI                 ~> sup2CI
  4012     join1E                  ~> sup1E
  4013     join2E                  ~> sup2E
  4014 
  4015     is_meet_Meet            ~> is_meet_Inf
  4016     Meet_bool_def           ~> Inf_bool_def
  4017     Meet_fun_def            ~> Inf_fun_def
  4018     Meet_greatest           ~> Inf_greatest
  4019     Meet_lower              ~> Inf_lower
  4020     Meet_set_def            ~> Inf_set_def
  4021 
  4022     Sup_def                 ~> Sup_Inf
  4023     Sup_bool_eq             ~> Sup_bool_def
  4024     Sup_fun_eq              ~> Sup_fun_def
  4025     Sup_set_eq              ~> Sup_set_def
  4026 
  4027     listsp_meetI            ~> listsp_infI
  4028     listsp_meet_eq          ~> listsp_inf_eq
  4029 
  4030     meet_min                ~> inf_min
  4031     join_max                ~> sup_max
  4032 
  4033 * Added syntactic class "size"; overloaded constant "size" now has
  4034 type "'a::size ==> bool"
  4035 
  4036 * Internal reorganisation of `size' of datatypes: size theorems
  4037 "foo.size" are no longer subsumed by "foo.simps" (but are still
  4038 simplification rules by default!); theorems "prod.size" now named
  4039 "*.size".
  4040 
  4041 * Class "div" now inherits from class "times" rather than "type".
  4042 INCOMPATIBILITY.
  4043 
  4044 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  4045 Linorder etc.  have disappeared; operations defined in terms of
  4046 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  4047 
  4048 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  4049 
  4050 * HOL-Word: New extensive library and type for generic, fixed size
  4051 machine words, with arithemtic, bit-wise, shifting and rotating
  4052 operations, reflection into int, nat, and bool lists, automation for
  4053 linear arithmetic (by automatic reflection into nat or int), including
  4054 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  4055 arithmetic type classes, supporting automatic simplification of
  4056 numerals on all operations.
  4057 
  4058 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  4059 
  4060 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  4061 
  4062 * Code generator library theories:
  4063   - Code_Integer represents HOL integers by big integer literals in target
  4064     languages.
  4065   - Code_Char represents HOL characters by character literals in target
  4066     languages.
  4067   - Code_Char_chr like Code_Char, but also offers treatment of character
  4068     codes; includes Code_Integer.
  4069   - Executable_Set allows to generate code for finite sets using lists.
  4070   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  4071     denominator).
  4072   - Executable_Real implements a subset of real numbers, namly those
  4073     representable by rational numbers.
  4074   - Efficient_Nat implements natural numbers by integers, which in general will
  4075     result in higher efficency; pattern matching with 0/Suc is eliminated;
  4076     includes Code_Integer.
  4077   - Code_Index provides an additional datatype index which is mapped to
  4078     target-language built-in integers.
  4079   - Code_Message provides an additional datatype message_string which is isomorphic to
  4080     strings; messages are mapped to target-language strings.
  4081 
  4082 * New package for inductive predicates
  4083 
  4084   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  4085 
  4086     inductive
  4087       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4088       for z_1 :: U_1 and ... and z_n :: U_m
  4089     where
  4090       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4091     | ...
  4092 
  4093   with full support for type-inference, rather than
  4094 
  4095     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4096 
  4097     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4098     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4099 
  4100     inductive "s z_1 ... z_m"
  4101     intros
  4102       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4103       ...
  4104 
  4105   For backward compatibility, there is a wrapper allowing inductive
  4106   sets to be defined with the new package via
  4107 
  4108     inductive_set
  4109       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4110       for z_1 :: U_1 and ... and z_n :: U_m
  4111     where
  4112       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4113     | ...
  4114 
  4115   or
  4116 
  4117     inductive_set
  4118       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4119       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4120       for z_1 :: U_1 and ... and z_n :: U_m
  4121     where
  4122       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4123     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4124     | ...
  4125 
  4126   if the additional syntax "p ..." is required.
  4127 
  4128   Numerous examples can be found in the subdirectories src/HOL/Auth,
  4129   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  4130 
  4131   INCOMPATIBILITIES:
  4132 
  4133   - Since declaration and definition of inductive sets or predicates
  4134     is no longer separated, abbreviations involving the newly
  4135     introduced sets or predicates must be specified together with the
  4136     introduction rules after the 'where' keyword (see above), rather
  4137     than before the actual inductive definition.
  4138 
  4139   - The variables in induction and elimination rules are now
  4140     quantified in the order of their occurrence in the introduction
  4141     rules, rather than in alphabetical order. Since this may break
  4142     some proofs, these proofs either have to be repaired, e.g. by
  4143     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  4144     statements of the form
  4145 
  4146       case (rule_i a_i_1 ... a_i_{k_i})
  4147 
  4148     or the old order of quantification has to be restored by explicitly adding
  4149     meta-level quantifiers in the introduction rules, i.e.
  4150 
  4151       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  4152 
  4153   - The format of the elimination rules is now
  4154 
  4155       p z_1 ... z_m x_1 ... x_n ==>
  4156         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4157         ==> ... ==> P
  4158 
  4159     for predicates and
  4160 
  4161       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4162         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4163         ==> ... ==> P
  4164 
  4165     for sets rather than
  4166 
  4167       x : s z_1 ... z_m ==>
  4168         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4169         ==> ... ==> P
  4170 
  4171     This may require terms in goals to be expanded to n-tuples
  4172     (e.g. using case_tac or simplification with the split_paired_all
  4173     rule) before the above elimination rule is applicable.
  4174 
  4175   - The elimination or case analysis rules for (mutually) inductive
  4176     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4177     list of rules "p_1_..._p_k.elims" is no longer available.
  4178 
  4179 * New package "function"/"fun" for general recursive functions,
  4180 supporting mutual and nested recursion, definitions in local contexts,
  4181 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4182 for small examples, and the separate tutorial on the function
  4183 package. The old recdef "package" is still available as before, but
  4184 users are encouraged to use the new package.
  4185 
  4186 * Method "lexicographic_order" automatically synthesizes termination
  4187 relations as lexicographic combinations of size measures. 
  4188 
  4189 * Case-expressions allow arbitrary constructor-patterns (including
  4190 "_") and take their order into account, like in functional
  4191 programming.  Internally, this is translated into nested
  4192 case-expressions; missing cases are added and mapped to the predefined
  4193 constant "undefined". In complicated cases printing may no longer show
  4194 the original input but the internal form. Lambda-abstractions allow
  4195 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4196 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4197 variable.
  4198 
  4199 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4200 is an abbreviation for "of_nat :: nat => int". The simplification
  4201 rules for "of_nat" have been changed to work like "int" did
  4202 previously.  Potential INCOMPATIBILITY:
  4203   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4204   - of_nat_diff and of_nat_mult are no longer default simp rules
  4205 
  4206 * Method "algebra" solves polynomial equations over (semi)rings using
  4207 Groebner bases. The (semi)ring structure is defined by locales and the
  4208 tool setup depends on that generic context. Installing the method for
  4209 a specific type involves instantiating the locale and possibly adding
  4210 declarations for computation on the coefficients.  The method is
  4211 already instantiated for natural numbers and for the axiomatic class
  4212 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4213 CALCULEMUS 2007 for the general principles underlying this
  4214 architecture of context-aware proof-tools.
  4215 
  4216 * Method "ferrack" implements quantifier elimination over
  4217 special-purpose dense linear orders using locales (analogous to
  4218 "algebra"). The method is already installed for class
  4219 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4220 rat, etc.
  4221 
  4222 * Former constant "List.op @" now named "List.append".  Use ML
  4223 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4224 circumvent possible incompatibilities when working on ML level.
  4225 
  4226 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4227 
  4228 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4229 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4230 
  4231 * New syntax for Haskell-like list comprehension (input only), eg.
  4232 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4233 
  4234 * The special syntax for function "filter" has changed from [x :
  4235 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4236 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4237 
  4238 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4239 defined on nat only, as an abbreviation for [a..<Suc b]
  4240 INCOMPATIBILITY.
  4241 
  4242 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4243 
  4244 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4245 
  4246 * New lemma collection field_simps (an extension of ring_simps) for
  4247 manipulating (in)equations involving division. Multiplies with all
  4248 denominators that can be proved to be non-zero (in equations) or
  4249 positive/negative (in inequations).
  4250 
  4251 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4252 have been improved and renamed to ring_simps, group_simps and
  4253 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4254 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4255 
  4256 * Theory Library/Commutative_Ring: switched from recdef to function
  4257 package; constants add, mul, pow now curried.  Infix syntax for
  4258 algebraic operations.
  4259 
  4260 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4261 INCOMPATIBILITY.
  4262 
  4263 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4264 INCOMPATIBILITY.
  4265 
  4266 * HOL/records: generalised field-update to take a function on the
  4267 field rather than the new value: r(|A := x|) is translated to A_update
  4268 (K x) r The K-combinator that is internally used is called K_record.
  4269 INCOMPATIBILITY: Usage of the plain update functions has to be
  4270 adapted.
  4271  
  4272 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4273 * x = 0, which are required for a semiring.  Richer structures do not
  4274 inherit from semiring_0 anymore, because this property is a theorem
  4275 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4276 there is more to prove, but this is mostly trivial.
  4277 
  4278 * Class "recpower" is generalized to arbitrary monoids, not just
  4279 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4280 commutativity or semiring properties additionally.
  4281 
  4282 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4283 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4284 better use 'abbreviation'.
  4285 
  4286 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4287 
  4288 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4289 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4290 significant changes for setting up numeral syntax for types:
  4291   - New constants Numeral.pred and Numeral.succ instead
  4292       of former Numeral.bin_pred and Numeral.bin_succ.
  4293   - Use integer operations instead of bin_add, bin_mult and so on.
  4294   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4295   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4296 
  4297 See src/HOL/Integ/IntArith.thy for an example setup.
  4298 
  4299 * Command 'normal_form' computes the normal form of a term that may
  4300 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4301 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4302 heavy-duty computations because the functions are compiled to ML
  4303 first.  Correspondingly, a method "normalization" is provided.  See
  4304 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4305 
  4306 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4307 25 like -->); output depends on the "iff" print_mode, the default is
  4308 "A = B" (with priority 50).
  4309 
  4310 * Relations less (<) and less_eq (<=) are also available on type bool.
  4311 Modified syntax to disallow nesting without explicit parentheses,
  4312 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4313 INCOMPATIBILITY.
  4314 
  4315 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4316 
  4317 * Relation composition operator "op O" now has precedence 75 and binds
  4318 stronger than union and intersection. INCOMPATIBILITY.
  4319 
  4320 * The old set interval syntax "{m..n(}" (and relatives) has been
  4321 removed.  Use "{m..<n}" (and relatives) instead.
  4322 
  4323 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4324 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4325 ``declare [[simproc del: neq]]''.
  4326 
  4327 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4328 True/False.
  4329 
  4330 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4331 
  4332 * Theorem setsum_mult renamed to setsum_right_distrib.
  4333 
  4334 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4335 ``rule'' method.
  4336 
  4337 * Reimplemented methods "sat" and "satx", with several improvements:
  4338 goals no longer need to be stated as "<prems> ==> False", equivalences
  4339 (i.e. "=" on type bool) are handled, variable names of the form
  4340 "lit_<n>" are no longer reserved, significant speedup.
  4341 
  4342 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4343 zChaff is still supported as well.
  4344 
  4345 * 'inductive' and 'datatype': provide projections of mutual rules,
  4346 bundled as foo_bar.inducts;
  4347 
  4348 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4349 Library.
  4350 
  4351 * Library: moved theory Accessible_Part to main HOL.
  4352 
  4353 * Library: added theory Coinductive_List of potentially infinite lists
  4354 as greatest fixed-point.
  4355 
  4356 * Library: added theory AssocList which implements (finite) maps as
  4357 association lists.
  4358 
  4359 * Method "evaluation" solves goals (i.e. a boolean expression)
  4360 efficiently by compiling it to ML.  The goal is "proved" (via an
  4361 oracle) if it evaluates to True.
  4362 
  4363 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4364 also when invoked by the simplifier.  This results in the Simplifier
  4365 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4366 Configuration option fast_arith_split_limit=0 recovers the old
  4367 behavior.
  4368 
  4369 * Support for hex (0x20) and binary (0b1001) numerals.
  4370 
  4371 * New method: reify eqs (t), where eqs are equations for an
  4372 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4373 parameter, computes a term s::'b and a list xs::'a list and proves the
  4374 theorem I xs s = t. This is also known as reification or quoting. The
  4375 resulting theorem is applied to the subgoal to substitute t with I xs
  4376 s.  If t is omitted, the subgoal itself is reified.
  4377 
  4378 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4379 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4380 where f is supposed to be a computable function (in the sense of code
  4381 generattion). The method uses reify to compute s and xs as above then
  4382 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4383 r and finally gets the theorem t = r, which is again applied to the
  4384 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4385 
  4386 * Reflection: Automatic reification now handels binding, an example is
  4387 available in src/HOL/ex/ReflectionEx.thy
  4388 
  4389 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4390 command 'statespace' that is similar to 'record', but introduces an
  4391 abstract specification based on the locale infrastructure instead of
  4392 HOL types.  This leads to extra flexibility in composing state spaces,
  4393 in particular multiple inheritance and renaming of components.
  4394 
  4395 
  4396 *** HOL-Complex ***
  4397 
  4398 * Hyperreal: Functions root and sqrt are now defined on negative real
  4399 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4400 Nonnegativity side conditions have been removed from many lemmas, so
  4401 that more subgoals may now be solved by simplification; potential
  4402 INCOMPATIBILITY.
  4403 
  4404 * Real: new type classes formalize real normed vector spaces and
  4405 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4406 and norm :: 'a => real.
  4407 
  4408 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4409 reals into other types. The overloaded constant Reals :: 'a set is now
  4410 defined as range of_real; potential INCOMPATIBILITY.
  4411 
  4412 * Real: proper support for ML code generation, including 'quickcheck'.
  4413 Reals are implemented as arbitrary precision rationals.
  4414 
  4415 * Hyperreal: Several constants that previously worked only for the
  4416 reals have been generalized, so they now work over arbitrary vector
  4417 spaces. Type annotations may need to be added in some cases; potential
  4418 INCOMPATIBILITY.
  4419 
  4420   Infinitesimal  :: ('a::real_normed_vector) star set
  4421   HFinite        :: ('a::real_normed_vector) star set
  4422   HInfinite      :: ('a::real_normed_vector) star set
  4423   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4424   monad          :: ('a::real_normed_vector) star => 'a star set
  4425   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4426   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4427   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4428   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4429   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4430   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4431   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4432   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4433   sgn            :: 'a::real_normed_vector => 'a
  4434   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4435 
  4436 * Complex: Some complex-specific constants are now abbreviations for
  4437 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4438 hnorm.  Other constants have been entirely removed in favor of the
  4439 polymorphic versions (INCOMPATIBILITY):
  4440 
  4441   approx        <-- capprox
  4442   HFinite       <-- CFinite
  4443   HInfinite     <-- CInfinite
  4444   Infinitesimal <-- CInfinitesimal
  4445   monad         <-- cmonad
  4446   galaxy        <-- cgalaxy
  4447   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4448   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4449   (ns)deriv     <-- (ns)cderiv
  4450 
  4451 
  4452 *** HOL-Algebra ***
  4453 
  4454 * Formalisation of ideals and the quotient construction over rings.
  4455 
  4456 * Order and lattice theory no longer based on records.
  4457 INCOMPATIBILITY.
  4458 
  4459 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4460 greatest_closed.  INCOMPATIBILITY.
  4461 
  4462 * Method algebra is now set up via an attribute.  For examples see
  4463 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4464 of algebraic structures.
  4465 
  4466 * Renamed theory CRing to Ring.
  4467 
  4468 
  4469 *** HOL-Nominal ***
  4470 
  4471 * Substantial, yet incomplete support for nominal datatypes (binding
  4472 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4473 src/HOL/Nominal/Examples.  Prospective users should consult
  4474 http://isabelle.in.tum.de/nominal/
  4475 
  4476 
  4477 *** ML ***
  4478 
  4479 * ML basics: just one true type int, which coincides with IntInf.int
  4480 (even on SML/NJ).
  4481 
  4482 * ML within Isar: antiquotations allow to embed statically-checked
  4483 formal entities in the source, referring to the context available at
  4484 compile-time.  For example:
  4485 
  4486 ML {* @{sort "{zero,one}"} *}
  4487 ML {* @{typ "'a => 'b"} *}
  4488 ML {* @{term "%x. x"} *}
  4489 ML {* @{prop "x == y"} *}
  4490 ML {* @{ctyp "'a => 'b"} *}
  4491 ML {* @{cterm "%x. x"} *}
  4492 ML {* @{cprop "x == y"} *}
  4493 ML {* @{thm asm_rl} *}
  4494 ML {* @{thms asm_rl} *}
  4495 ML {* @{type_name c} *}
  4496 ML {* @{type_syntax c} *}
  4497 ML {* @{const_name c} *}
  4498 ML {* @{const_syntax c} *}
  4499 ML {* @{context} *}
  4500 ML {* @{theory} *}
  4501 ML {* @{theory Pure} *}
  4502 ML {* @{theory_ref} *}
  4503 ML {* @{theory_ref Pure} *}
  4504 ML {* @{simpset} *}
  4505 ML {* @{claset} *}
  4506 ML {* @{clasimpset} *}
  4507 
  4508 The same works for sources being ``used'' within an Isar context.
  4509 
  4510 * ML in Isar: improved error reporting; extra verbosity with
  4511 ML_Context.trace enabled.
  4512 
  4513 * Pure/General/table.ML: the join operations now works via exceptions
  4514 DUP/SAME instead of type option. This is simpler in simple cases, and
  4515 admits slightly more efficient complex applications.
  4516 
  4517 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4518 use Context.generic instead of just theory.
  4519 
  4520 * Pure: datatype Context.generic joins theory/Proof.context and
  4521 provides some facilities for code that works in either kind of
  4522 context, notably GenericDataFun for uniform theory and proof data.
  4523 
  4524 * Pure: simplified internal attribute type, which is now always
  4525 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4526 local (Proof.context) attributes have been discontinued, while
  4527 minimizing code duplication. Thm.rule_attribute and
  4528 Thm.declaration_attribute build canonical attributes; see also structure
  4529 Context for further operations on Context.generic, notably
  4530 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4531 declarations and definitions.
  4532 
  4533 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4534 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4535 init only required for impure data. INCOMPATIBILITY: empty really need
  4536 to be empty (no dependencies on theory content!)
  4537 
  4538 * Pure/kernel: consts certification ignores sort constraints given in
  4539 signature declarations. (This information is not relevant to the
  4540 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4541 potential INCOMPATIBILITY.
  4542 
  4543 * Pure: axiomatic type classes are now purely definitional, with
  4544 explicit proofs of class axioms and super class relations performed
  4545 internally. See Pure/axclass.ML for the main internal interfaces --
  4546 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4547 AxClass.axiomatize_class/classrel/arity supersede
  4548 Sign.add_classes/classrel/arities.
  4549 
  4550 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4551 global/local versions on theory vs. Proof.context have been
  4552 discontinued; Attrib.syntax and Method.syntax have been adapted
  4553 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4554 attributes, methods, etc.
  4555 
  4556 * Pure: several functions of signature "... -> theory -> theory * ..."
  4557 have been reoriented to "... -> theory -> ... * theory" in order to
  4558 allow natural usage in combination with the ||>, ||>>, |-> and
  4559 fold_map combinators.
  4560 
  4561 * Pure: official theorem names (closed derivations) and additional
  4562 comments (tags) are now strictly separate.  Name hints -- which are
  4563 maintained as tags -- may be attached any time without affecting the
  4564 derivation.
  4565 
  4566 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4567 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4568 achieve the old behaviour.
  4569 
  4570 * Pure: the "Goal" constant is now called "prop", supporting a
  4571 slightly more general idea of ``protecting'' meta-level rule
  4572 statements.
  4573 
  4574 * Pure: Logic.(un)varify only works in a global context, which is now
  4575 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4576 Logic.legacy_(un)varify as temporary workaround.
  4577 
  4578 * Pure: structure Name provides scalable operations for generating
  4579 internal variable names, notably Name.variants etc.  This replaces
  4580 some popular functions from term.ML:
  4581 
  4582   Term.variant		->  Name.variant
  4583   Term.variantlist	->  Name.variant_list
  4584   Term.invent_names	->  Name.invent_list
  4585 
  4586 Note that low-level renaming rarely occurs in new code -- operations
  4587 from structure Variable are used instead (see below).
  4588 
  4589 * Pure: structure Variable provides fundamental operations for proper
  4590 treatment of fixed/schematic variables in a context.  For example,
  4591 Variable.import introduces fixes for schematics of given facts and
  4592 Variable.export reverses the effect (up to renaming) -- this replaces
  4593 various freeze_thaw operations.
  4594 
  4595 * Pure: structure Goal provides simple interfaces for
  4596 init/conclude/finish and tactical prove operations (replacing former
  4597 Tactic.prove).  Goal.prove is the canonical way to prove results
  4598 within a given context; Goal.prove_global is a degraded version for
  4599 theory level goals, including a global Drule.standard.  Note that
  4600 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4601 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4602 in a locale context).
  4603 
  4604 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4605 and type checking (Syntax.check_term etc.), with common combinations
  4606 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4607 which are considered legacy and await removal.
  4608 
  4609 * Pure/Syntax: generic interfaces for type unchecking
  4610 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4611 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4612 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4613 available for convenience, but refer to the very same operations using
  4614 a mere theory instead of a full context.
  4615 
  4616 * Isar: simplified treatment of user-level errors, using exception
  4617 ERROR of string uniformly.  Function error now merely raises ERROR,
  4618 without any side effect on output channels.  The Isar toplevel takes
  4619 care of proper display of ERROR exceptions.  ML code may use plain
  4620 handle/can/try; cat_error may be used to concatenate errors like this:
  4621 
  4622   ... handle ERROR msg => cat_error msg "..."
  4623 
  4624 Toplevel ML code (run directly or through the Isar toplevel) may be
  4625 embedded into the Isar toplevel with exception display/debug like
  4626 this:
  4627 
  4628   Isar.toplevel (fn () => ...)
  4629 
  4630 INCOMPATIBILITY, removed special transform_error facilities, removed
  4631 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4632 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4633 -- use plain ERROR instead.
  4634 
  4635 * Isar: theory setup now has type (theory -> theory), instead of a
  4636 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4637 
  4638 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4639 ProofContext.debug/verbose flags.
  4640 
  4641 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4642 theory before entering a proof state.  Transactions now always see a
  4643 quasi-functional intermediate checkpoint, both in interactive and
  4644 batch mode.
  4645 
  4646 * Isar: simplified interfaces for outer syntax.  Renamed
  4647 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4648 OuterSyntax.add_parsers -- this functionality is now included in
  4649 OuterSyntax.command etc.  INCOMPATIBILITY.
  4650 
  4651 * Simplifier: the simpset of a running simplification process now
  4652 contains a proof context (cf. Simplifier.the_context), which is the
  4653 very context that the initial simpset has been retrieved from (by
  4654 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4655 (solver, looper etc.) may depend on arbitrary proof data.
  4656 
  4657 * Simplifier.inherit_context inherits the proof context (plus the
  4658 local bounds) of the current simplification process; any simproc
  4659 etc. that calls the Simplifier recursively should do this!  Removed
  4660 former Simplifier.inherit_bounds, which is already included here --
  4661 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4662 specify an explicit context using Simplifier.context/theory_context.
  4663 
  4664 * Simplifier/Classical Reasoner: more abstract interfaces
  4665 change_simpset/claset for modifying the simpset/claset reference of a
  4666 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4667 INCOMPATIBILITY.
  4668 
  4669 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4670 "Trueprop" etc.
  4671 
  4672 
  4673 *** System ***
  4674 
  4675 * settings: the default heap location within ISABELLE_HOME_USER now
  4676 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4677 Isabelle installations.
  4678 
  4679 * isabelle-process: option -S (secure mode) disables some critical
  4680 operations, notably runtime compilation and evaluation of ML source
  4681 code.
  4682 
  4683 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4684 
  4685 * Support for parallel execution, using native multicore support of
  4686 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4687 independent theories, according to the given theory header
  4688 specifications. The maximum number of worker threads is specified via
  4689 usedir option -M or the "max-threads" setting in Proof General. A
  4690 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4691 to 6 on a 8-core machine.  User-code needs to observe certain
  4692 guidelines for thread-safe programming, see appendix A in the Isar
  4693 Implementation manual.
  4694 
  4695 
  4696 
  4697 New in Isabelle2005 (October 2005)
  4698 ----------------------------------
  4699 
  4700 *** General ***
  4701 
  4702 * Theory headers: the new header syntax for Isar theories is
  4703 
  4704   theory <name>
  4705   imports <theory1> ... <theoryN>
  4706   uses <file1> ... <fileM>
  4707   begin
  4708 
  4709 where the 'uses' part is optional.  The previous syntax
  4710 
  4711   theory <name> = <theory1> + ... + <theoryN>:
  4712 
  4713 will disappear in the next release.  Use isatool fixheaders to convert
  4714 existing theory files.  Note that there is no change in ancient
  4715 non-Isar theories now, but these will disappear soon.
  4716 
  4717 * Theory loader: parent theories can now also be referred to via
  4718 relative and absolute paths.
  4719 
  4720 * Command 'find_theorems' searches for a list of criteria instead of a
  4721 list of constants. Known criteria are: intro, elim, dest, name:string,
  4722 simp:term, and any term. Criteria can be preceded by '-' to select
  4723 theorems that do not match. Intro, elim, dest select theorems that
  4724 match the current goal, name:s selects theorems whose fully qualified
  4725 name contain s, and simp:term selects all simplification rules whose
  4726 lhs match term.  Any other term is interpreted as pattern and selects
  4727 all theorems matching the pattern. Available in ProofGeneral under
  4728 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4729 
  4730   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4731 
  4732 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4733 matching the current goal as introduction rule and not having "HOL."
  4734 in their name (i.e. not being defined in theory HOL).
  4735 
  4736 * Command 'thms_containing' has been discontinued in favour of
  4737 'find_theorems'; INCOMPATIBILITY.
  4738 
  4739 * Communication with Proof General is now 8bit clean, which means that
  4740 Unicode text in UTF-8 encoding may be used within theory texts (both
  4741 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4742 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4743 
  4744   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4745   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4746 
  4747 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4748 Classical Reasoner.  Typical big applications run around 2 times
  4749 faster.
  4750 
  4751 
  4752 *** Document preparation ***
  4753 
  4754 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4755 of raw sources.  Only those symbols that do not require additional
  4756 LaTeX packages (depending on comments in isabellesym.sty) are
  4757 displayed properly, everything else is left verbatim.  isatool display
  4758 and isatool print are used as front ends (these are subject to the
  4759 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4760 
  4761 * Command tags control specific markup of certain regions of text,
  4762 notably folding and hiding.  Predefined tags include "theory" (for
  4763 theory begin and end), "proof" for proof commands, and "ML" for
  4764 commands involving ML code; the additional tags "visible" and
  4765 "invisible" are unused by default.  Users may give explicit tag
  4766 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4767 interpretation of tags is determined by the LaTeX job during document
  4768 preparation: see option -V of isatool usedir, or options -n and -t of
  4769 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4770 \isadroptag.
  4771 
  4772 Several document versions may be produced at the same time via isatool
  4773 usedir (the generated index.html will link all of them).  Typical
  4774 specifications include ''-V document=theory,proof,ML'' to present
  4775 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4776 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4777 these parts without any formal replacement text.  The Isabelle site
  4778 default settings produce ''document'' and ''outline'' versions as
  4779 specified above.
  4780 
  4781 * Several new antiquotations:
  4782 
  4783   @{term_type term} prints a term with its type annotated;
  4784 
  4785   @{typeof term} prints the type of a term;
  4786 
  4787   @{const const} is the same as @{term const}, but checks that the
  4788   argument is a known logical constant;
  4789 
  4790   @{term_style style term} and @{thm_style style thm} print a term or
  4791   theorem applying a "style" to it
  4792 
  4793   @{ML text}
  4794 
  4795 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4796 definitions, equations, inequations etc., 'concl' printing only the
  4797 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4798 to print the specified premise.  TermStyle.add_style provides an ML
  4799 interface for introducing further styles.  See also the "LaTeX Sugar"
  4800 document practical applications.  The ML antiquotation prints
  4801 type-checked ML expressions verbatim.
  4802 
  4803 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4804 and 'text' support optional locale specification '(in loc)', which
  4805 specifies the default context for interpreting antiquotations.  For
  4806 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4807 
  4808 * Option 'locale=NAME' of antiquotations specifies an alternative
  4809 context interpreting the subsequent argument.  For example: @{thm
  4810 [locale=lattice] inf_assoc}.
  4811 
  4812 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4813 a proof context.
  4814 
  4815 * Proper output of antiquotations for theory commands involving a
  4816 proof context (such as 'locale' or 'theorem (in loc) ...').
  4817 
  4818 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4819 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4820 
  4821 * isatool usedir: new option -C (default true) controls whether option
  4822 -D should include a copy of the original document directory; -C false
  4823 prevents unwanted effects such as copying of administrative CVS data.
  4824 
  4825 
  4826 *** Pure ***
  4827 
  4828 * Considerably improved version of 'constdefs' command.  Now performs
  4829 automatic type-inference of declared constants; additional support for
  4830 local structure declarations (cf. locales and HOL records), see also
  4831 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4832 sequential dependencies of definitions within a single 'constdefs'
  4833 section; moreover, the declared name needs to be an identifier.  If
  4834 all fails, consider to fall back on 'consts' and 'defs' separately.
  4835 
  4836 * Improved indexed syntax and implicit structures.  First of all,
  4837 indexed syntax provides a notational device for subscripted
  4838 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4839 expressions.  Secondly, in a local context with structure
  4840 declarations, number indexes \<^sub>n or the empty index (default
  4841 number 1) refer to a certain fixed variable implicitly; option
  4842 show_structs controls printing of implicit structures.  Typical
  4843 applications of these concepts involve record types and locales.
  4844 
  4845 * New command 'no_syntax' removes grammar declarations (and
  4846 translations) resulting from the given syntax specification, which is
  4847 interpreted in the same manner as for the 'syntax' command.
  4848 
  4849 * 'Advanced' translation functions (parse_translation etc.) may depend
  4850 on the signature of the theory context being presently used for
  4851 parsing/printing, see also isar-ref manual.
  4852 
  4853 * Improved 'oracle' command provides a type-safe interface to turn an
  4854 ML expression of type theory -> T -> term into a primitive rule of
  4855 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4856 is already included here); see also FOL/ex/IffExample.thy;
  4857 INCOMPATIBILITY.
  4858 
  4859 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4860 before); "cI" is no longer bound, use "c.intro" instead.
  4861 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4862 axclasses vs. locales.
  4863 
  4864 * Improved internal renaming of symbolic identifiers -- attach primes
  4865 instead of base 26 numbers.
  4866 
  4867 * New flag show_question_marks controls printing of leading question
  4868 marks in schematic variable names.
  4869 
  4870 * In schematic variable names, *any* symbol following \<^isub> or
  4871 \<^isup> is now treated as part of the base name.  For example, the
  4872 following works without printing of awkward ".0" indexes:
  4873 
  4874   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4875     by simp
  4876 
  4877 * Inner syntax includes (*(*nested*) comments*).
  4878 
  4879 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4880 annotations as "(00...)".
  4881 
  4882 * Clear separation of logical types and nonterminals, where the latter
  4883 may only occur in 'syntax' specifications or type abbreviations.
  4884 Before that distinction was only partially implemented via type class
  4885 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4886 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4887 exotic syntax specifications may require further adaption
  4888 (e.g. Cube/Cube.thy).
  4889 
  4890 * Removed obsolete type class "logic", use the top sort {} instead.
  4891 Note that non-logical types should be declared as 'nonterminals'
  4892 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4893 specifications.
  4894 
  4895 * Attributes 'induct' and 'cases': type or set names may now be
  4896 locally fixed variables as well.
  4897 
  4898 * Simplifier: can now control the depth to which conditional rewriting
  4899 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4900 Limit.
  4901 
  4902 * Simplifier: simplification procedures may now take the current
  4903 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4904 interface), which is very useful for calling the Simplifier
  4905 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4906 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4907 low-level mk_simproc no longer applies Logic.varify internally, to
  4908 allow for use in a context of fixed variables.
  4909 
  4910 * thin_tac now works even if the assumption being deleted contains !!
  4911 or ==>.  More generally, erule now works even if the major premise of
  4912 the elimination rule contains !! or ==>.
  4913 
  4914 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4915 
  4916 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4917 from Pure, which contains all common declarations already.  Both
  4918 theories are defined via plain Isabelle/Isar .thy files.
  4919 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4920 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4921 use isatool fixcpure to adapt your theory and ML sources.
  4922 
  4923 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4924 selections of theorems in named facts via index ranges.
  4925 
  4926 * 'print_theorems': in theory mode, really print the difference
  4927 wrt. the last state (works for interactive theory development only),
  4928 in proof mode print all local facts (cf. 'print_facts');
  4929 
  4930 * 'hide': option '(open)' hides only base names.
  4931 
  4932 * More efficient treatment of intermediate checkpoints in interactive
  4933 theory development.
  4934 
  4935 * Code generator is now invoked via code_module (incremental code
  4936 generation) and code_library (modular code generation, ML structures
  4937 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4938 must be quoted when used as identifiers.
  4939 
  4940 * New 'value' command for reading, evaluating and printing terms using
  4941 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4942 quoted when used as identifier.
  4943 
  4944 
  4945 *** Locales ***
  4946 
  4947 * New commands for the interpretation of locale expressions in
  4948 theories (1), locales (2) and proof contexts (3).  These generate
  4949 proof obligations from the expression specification.  After the
  4950 obligations have been discharged, theorems of the expression are added
  4951 to the theory, target locale or proof context.  The synopsis of the
  4952 commands is a follows:
  4953 
  4954   (1) interpretation expr inst
  4955   (2) interpretation target < expr
  4956   (3) interpret expr inst
  4957 
  4958 Interpretation in theories and proof contexts require a parameter
  4959 instantiation of terms from the current context.  This is applied to
  4960 specifications and theorems of the interpreted expression.
  4961 Interpretation in locales only permits parameter renaming through the
  4962 locale expression.  Interpretation is smart in that interpretations
  4963 that are active already do not occur in proof obligations, neither are
  4964 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4965 inspect active interpretations of a particular locale.  For details,
  4966 see the Isar Reference manual.  Examples can be found in
  4967 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4968 
  4969 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4970 'interpret' instead.
  4971 
  4972 * New context element 'constrains' for adding type constraints to
  4973 parameters.
  4974 
  4975 * Context expressions: renaming of parameters with syntax
  4976 redeclaration.
  4977 
  4978 * Locale declaration: 'includes' disallowed.
  4979 
  4980 * Proper static binding of attribute syntax -- i.e. types / terms /
  4981 facts mentioned as arguments are always those of the locale definition
  4982 context, independently of the context of later invocations.  Moreover,
  4983 locale operations (renaming and type / term instantiation) are applied
  4984 to attribute arguments as expected.
  4985 
  4986 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4987 actual attributes; rare situations may require Attrib.attribute to
  4988 embed those attributes into Attrib.src that lack concrete syntax.
  4989 Attribute implementations need to cooperate properly with the static
  4990 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4991 Attrib.XXX_thm etc. already do the right thing without further
  4992 intervention.  Only unusual applications -- such as "where" or "of"
  4993 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4994 on the context and the facts involved -- may have to assign parsed
  4995 values to argument tokens explicitly.
  4996 
  4997 * Changed parameter management in theorem generation for long goal
  4998 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4999 theorem statement in rare situations.
  5000 
  5001 * Locale inspection command 'print_locale' omits notes elements.  Use
  5002 'print_locale!' to have them included in the output.
  5003 
  5004 
  5005 *** Provers ***
  5006 
  5007 * Provers/hypsubst.ML: improved version of the subst method, for
  5008 single-step rewriting: it now works in bound variable contexts. New is
  5009 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  5010 rewrite a different subterm than the original subst method, which is
  5011 still available as 'simplesubst'.
  5012 
  5013 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  5014 and quasi orders.
  5015 
  5016 * Provers/trancl.ML: new transitivity reasoner for transitive and
  5017 reflexive-transitive closure of relations.
  5018 
  5019 * Provers/blast.ML: new reference depth_limit to make blast's depth
  5020 limit (previously hard-coded with a value of 20) user-definable.
  5021 
  5022 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  5023 is peformed already.  Object-logics merely need to finish their
  5024 initial simpset configuration as before.  INCOMPATIBILITY.
  5025 
  5026 
  5027 *** HOL ***
  5028 
  5029 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  5030 
  5031   syntax (epsilon)
  5032     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  5033 
  5034 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  5035 and x-symbol; use option '-m epsilon' to get it actually printed.
  5036 Moreover, the mathematically important symbolic identifier \<epsilon>
  5037 becomes available as variable, constant etc.  INCOMPATIBILITY,
  5038 
  5039 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  5040 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  5041 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  5042 support corresponding Isar calculations.
  5043 
  5044 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  5045 instead of ":".
  5046 
  5047 * theory SetInterval: changed the syntax for open intervals:
  5048 
  5049   Old       New
  5050   {..n(}    {..<n}
  5051   {)n..}    {n<..}
  5052   {m..n(}   {m..<n}
  5053   {)m..n}   {m<..n}
  5054   {)m..n(}  {m<..<n}
  5055 
  5056 The old syntax is still supported but will disappear in the next
  5057 release.  For conversion use the following Emacs search and replace
  5058 patterns (these are not perfect but work quite well):
  5059 
  5060   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  5061   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  5062 
  5063 * Theory Commutative_Ring (in Library): method comm_ring for proving
  5064 equalities in commutative rings; method 'algebra' provides a generic
  5065 interface.
  5066 
  5067 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  5068 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  5069 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  5070 be a tuple pattern.
  5071 
  5072 Some new syntax forms are available:
  5073 
  5074   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  5075   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  5076   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  5077   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  5078 
  5079 The latter form "\<Sum>x < k. e" used to be based on a separate
  5080 function "Summation", which has been discontinued.
  5081 
  5082 * theory Finite_Set: in structured induction proofs, the insert case
  5083 is now 'case (insert x F)' instead of the old counterintuitive 'case
  5084 (insert F x)'.
  5085 
  5086 * The 'refute' command has been extended to support a much larger
  5087 fragment of HOL, including axiomatic type classes, constdefs and
  5088 typedefs, inductive datatypes and recursion.
  5089 
  5090 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  5091 Requires zChaff with proof generation to be installed.  See
  5092 HOL/ex/SAT_Examples.thy for examples.
  5093 
  5094 * Datatype induction via method 'induct' now preserves the name of the
  5095 induction variable. For example, when proving P(xs::'a list) by
  5096 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  5097 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  5098 in unstructured proof scripts.
  5099 
  5100 * Reworked implementation of records.  Improved scalability for
  5101 records with many fields, avoiding performance problems for type
  5102 inference. Records are no longer composed of nested field types, but
  5103 of nested extension types. Therefore the record type only grows linear
  5104 in the number of extensions and not in the number of fields.  The
  5105 top-level (users) view on records is preserved.  Potential
  5106 INCOMPATIBILITY only in strange cases, where the theory depends on the
  5107 old record representation. The type generated for a record is called
  5108 <record_name>_ext_type.
  5109 
  5110 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  5111 proofs triggered by a record definition or a simproc (if
  5112 quick_and_dirty is enabled).  Definitions of large records can take
  5113 quite long.
  5114 
  5115 New simproc record_upd_simproc for simplification of multiple record
  5116 updates enabled by default.  Moreover, trivial updates are also
  5117 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  5118 occasionally, since simplification is more powerful by default.
  5119 
  5120 * typedef: proper support for polymorphic sets, which contain extra
  5121 type-variables in the term.
  5122 
  5123 * Simplifier: automatically reasons about transitivity chains
  5124 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  5125 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  5126 old proofs break occasionally as simplification may now solve more
  5127 goals than previously.
  5128 
  5129 * Simplifier: converts x <= y into x = y if assumption y <= x is
  5130 present.  Works for all partial orders (class "order"), in particular
  5131 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  5132 just like y <= x.
  5133 
  5134 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  5135 bound variable or a constant then the let is unfolded.  Otherwise
  5136 first a is simplified to b, and then f b is simplified to g. If
  5137 possible we abstract b from g arriving at "let x = b in h x",
  5138 otherwise we unfold the let and arrive at g.  The simproc can be
  5139 enabled/disabled by the reference use_let_simproc.  Potential
  5140 INCOMPATIBILITY since simplification is more powerful by default.
  5141 
  5142 * Classical reasoning: the meson method now accepts theorems as arguments.
  5143 
  5144 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  5145 jobs to provide advice on the provability of subgoals.
  5146 
  5147 * Theory OrderedGroup and Ring_and_Field: various additions and
  5148 improvements to faciliate calculations involving equalities and
  5149 inequalities.
  5150 
  5151 The following theorems have been eliminated or modified
  5152 (INCOMPATIBILITY):
  5153 
  5154   abs_eq             now named abs_of_nonneg
  5155   abs_of_ge_0        now named abs_of_nonneg
  5156   abs_minus_eq       now named abs_of_nonpos
  5157   imp_abs_id         now named abs_of_nonneg
  5158   imp_abs_neg_id     now named abs_of_nonpos
  5159   mult_pos           now named mult_pos_pos
  5160   mult_pos_le        now named mult_nonneg_nonneg
  5161   mult_pos_neg_le    now named mult_nonneg_nonpos
  5162   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5163   mult_neg           now named mult_neg_neg
  5164   mult_neg_le        now named mult_nonpos_nonpos
  5165 
  5166 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5167      
  5168      zero_le_square
  5169      not_square_less_zero 
  5170 
  5171   The following lemmas have been deleted from Real/RealPow:
  5172   
  5173      realpow_zero_zero
  5174      realpow_two
  5175      realpow_less
  5176      zero_le_power
  5177      realpow_two_le
  5178      abs_realpow_two
  5179      realpow_two_abs     
  5180 
  5181 * Theory Parity: added rules for simplifying exponents.
  5182 
  5183 * Theory List:
  5184 
  5185 The following theorems have been eliminated or modified
  5186 (INCOMPATIBILITY):
  5187 
  5188   list_all_Nil       now named list_all.simps(1)
  5189   list_all_Cons      now named list_all.simps(2)
  5190   list_all_conv      now named list_all_iff
  5191   set_mem_eq         now named mem_iff
  5192 
  5193 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5194 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5195 
  5196 
  5197 *** HOL-Complex ***
  5198 
  5199 * Theory RealDef: better support for embedding natural numbers and
  5200 integers in the reals.
  5201 
  5202 The following theorems have been eliminated or modified
  5203 (INCOMPATIBILITY):
  5204 
  5205   exp_ge_add_one_self  now requires no hypotheses
  5206   real_of_int_add      reversed direction of equality (use [symmetric])
  5207   real_of_int_minus    reversed direction of equality (use [symmetric])
  5208   real_of_int_diff     reversed direction of equality (use [symmetric])
  5209   real_of_int_mult     reversed direction of equality (use [symmetric])
  5210 
  5211 * Theory RComplete: expanded support for floor and ceiling functions.
  5212 
  5213 * Theory Ln is new, with properties of the natural logarithm
  5214 
  5215 * Hyperreal: There is a new type constructor "star" for making
  5216 nonstandard types.  The old type names are now type synonyms:
  5217 
  5218   hypreal = real star
  5219   hypnat = nat star
  5220   hcomplex = complex star
  5221 
  5222 * Hyperreal: Many groups of similarly-defined constants have been
  5223 replaced by polymorphic versions (INCOMPATIBILITY):
  5224 
  5225   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5226 
  5227   starset      <-- starsetNat, starsetC
  5228   *s*          <-- *sNat*, *sc*
  5229   starset_n    <-- starsetNat_n, starsetC_n
  5230   *sn*         <-- *sNatn*, *scn*
  5231   InternalSets <-- InternalNatSets, InternalCSets
  5232 
  5233   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5234   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5235   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5236   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5237   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5238 
  5239 * Hyperreal: Many type-specific theorems have been removed in favor of
  5240 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5241 
  5242   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5243   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5244   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5245   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5246   right_minus <-- hypreal_add_minus
  5247   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5248   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5249   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5250   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5251   mult_1_right <-- hcomplex_mult_one_right
  5252   mult_zero_left <-- hcomplex_mult_zero_left
  5253   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5254   right_distrib <-- hypnat_add_mult_distrib2
  5255   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5256   right_inverse <-- hypreal_mult_inverse
  5257   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5258   order_refl <-- {hypreal,hypnat}_le_refl
  5259   order_trans <-- {hypreal,hypnat}_le_trans
  5260   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5261   order_less_le <-- {hypreal,hypnat}_less_le
  5262   linorder_linear <-- {hypreal,hypnat}_le_linear
  5263   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5264   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5265   add_nonneg_nonneg <-- hypreal_le_add_order
  5266 
  5267 * Hyperreal: Separate theorems having to do with type-specific
  5268 versions of constants have been merged into theorems that apply to the
  5269 new polymorphic constants (INCOMPATIBILITY):
  5270 
  5271   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5272   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5273   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5274   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5275   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5276   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5277   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5278   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5279   STAR_diff <-- {STAR,STARC}_diff
  5280   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5281     STARC_hcomplex_of_complex}_image_subset
  5282   starset_n_Un <-- starset{Nat,C}_n_Un
  5283   starset_n_Int <-- starset{Nat,C}_n_Int
  5284   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5285   starset_n_diff <-- starset{Nat,C}_n_diff
  5286   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5287   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5288   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5289   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5290   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5291   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5292   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5293   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5294   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5295   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5296   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5297   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5298   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5299   starfun_diff <-- starfun{C,RC,CR}_diff
  5300   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5301   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5302   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5303   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5304   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5305   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5306   starfun_Id <-- starfunC_Id
  5307   starfun_approx <-- starfun{Nat,CR}_approx
  5308   starfun_capprox <-- starfun{C,RC}_capprox
  5309   starfun_abs <-- starfunNat_rabs
  5310   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5311   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5312   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5313   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5314   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5315   starfun_add_approx <-- starfunCR_add_approx
  5316   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5317   starfun_divide <-- starfun{C,CR,RC}_divide
  5318   starfun_n <-- starfun{Nat,C}_n
  5319   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5320   starfun_n_add <-- starfun{Nat,C}_n_add
  5321   starfun_n_add_minus <-- starfunNat_n_add_minus
  5322   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5323   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5324   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5325 
  5326   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5327   star_n_minus <-- {hypreal,hcomplex}_minus
  5328   star_n_diff <-- {hypreal,hcomplex}_diff
  5329   star_n_mult <-- {hypreal,hcomplex}_mult
  5330   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5331   star_n_le <-- {hypreal,hypnat}_le
  5332   star_n_less <-- {hypreal,hypnat}_less
  5333   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5334   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5335   star_n_abs <-- hypreal_hrabs
  5336   star_n_divide <-- hcomplex_divide
  5337 
  5338   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5339   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5340   star_of_diff <-- hypreal_of_real_diff
  5341   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5342   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5343   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5344   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5345   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5346   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5347   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5348   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5349   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5350   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5351   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5352   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5353   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5354   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5355   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5356   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5357   star_of_power <-- hypreal_of_real_power
  5358   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5359 
  5360 * Hyperreal: new method "transfer" that implements the transfer
  5361 principle of nonstandard analysis. With a subgoal that mentions
  5362 nonstandard types like "'a star", the command "apply transfer"
  5363 replaces it with an equivalent one that mentions only standard types.
  5364 To be successful, all free variables must have standard types; non-
  5365 standard variables must have explicit universal quantifiers.
  5366 
  5367 * Hyperreal: A theory of Taylor series.
  5368 
  5369 
  5370 *** HOLCF ***
  5371 
  5372 * Discontinued special version of 'constdefs' (which used to support
  5373 continuous functions) in favor of the general Pure one with full
  5374 type-inference.
  5375 
  5376 * New simplification procedure for solving continuity conditions; it
  5377 is much faster on terms with many nested lambda abstractions (cubic
  5378 instead of exponential time).
  5379 
  5380 * New syntax for domain package: selector names are now optional.
  5381 Parentheses should be omitted unless argument is lazy, for example:
  5382 
  5383   domain 'a stream = cons "'a" (lazy "'a stream")
  5384 
  5385 * New command 'fixrec' for defining recursive functions with pattern
  5386 matching; defining multiple functions with mutual recursion is also
  5387 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5388 sinr, or any data constructor defined by the domain package. The given
  5389 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5390 syntax and examples.
  5391 
  5392 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5393 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5394 but the proof obligation additionally includes an admissibility
  5395 requirement. The packages generate instances of class cpo or pcpo,
  5396 with continuity and strictness theorems for Rep and Abs.
  5397 
  5398 * HOLCF: Many theorems have been renamed according to a more standard naming
  5399 scheme (INCOMPATIBILITY):
  5400 
  5401   foo_inject:  "foo$x = foo$y ==> x = y"
  5402   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5403   foo_less:    "(foo$x << foo$y) = (x << y)"
  5404   foo_strict:  "foo$UU = UU"
  5405   foo_defined: "... ==> foo$x ~= UU"
  5406   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5407 
  5408 
  5409 *** ZF ***
  5410 
  5411 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5412 including the First Isomorphism Theorem (on quotienting by the kernel
  5413 of a homomorphism).
  5414 
  5415 * ZF/Simplifier: install second copy of type solver that actually
  5416 makes use of TC rules declared to Isar proof contexts (or locales);
  5417 the old version is still required for ML proof scripts.
  5418 
  5419 
  5420 *** Cube ***
  5421 
  5422 * Converted to Isar theory format; use locales instead of axiomatic
  5423 theories.
  5424 
  5425 
  5426 *** ML ***
  5427 
  5428 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5429 for ||>, ||>>, |>>,
  5430 
  5431 * Pure/library.ML no longer defines its own option datatype, but uses
  5432 that of the SML basis, which has constructors NONE and SOME instead of
  5433 None and Some, as well as exception Option.Option instead of OPTION.
  5434 The functions the, if_none, is_some, is_none have been adapted
  5435 accordingly, while Option.map replaces apsome.
  5436 
  5437 * Pure/library.ML: the exception LIST has been given up in favour of
  5438 the standard exceptions Empty and Subscript, as well as
  5439 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5440 superceded by the standard hd and tl functions etc.
  5441 
  5442 A number of basic list functions are no longer exported to the ML
  5443 toplevel, as they are variants of predefined functions.  The following
  5444 suggests how one can translate existing code:
  5445 
  5446     rev_append xs ys = List.revAppend (xs, ys)
  5447     nth_elem (i, xs) = List.nth (xs, i)
  5448     last_elem xs = List.last xs
  5449     flat xss = List.concat xss
  5450     seq fs = List.app fs
  5451     partition P xs = List.partition P xs
  5452     mapfilter f xs = List.mapPartial f xs
  5453 
  5454 * Pure/library.ML: several combinators for linear functional
  5455 transformations, notably reverse application and composition:
  5456 
  5457   x |> f                f #> g
  5458   (x, y) |-> f          f #-> g
  5459 
  5460 * Pure/library.ML: introduced/changed precedence of infix operators:
  5461 
  5462   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5463   infix 2 ?;
  5464   infix 3 o oo ooo oooo;
  5465   infix 4 ~~ upto downto;
  5466 
  5467 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5468 infix operators.
  5469 
  5470 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5471 fold_map support linear functional transformations and nesting.  For
  5472 example:
  5473 
  5474   fold f [x1, ..., xN] y =
  5475     y |> f x1 |> ... |> f xN
  5476 
  5477   (fold o fold) f [xs1, ..., xsN] y =
  5478     y |> fold f xs1 |> ... |> fold f xsN
  5479 
  5480   fold f [x1, ..., xN] =
  5481     f x1 #> ... #> f xN
  5482 
  5483   (fold o fold) f [xs1, ..., xsN] =
  5484     fold f xs1 #> ... #> fold f xsN
  5485 
  5486 * Pure/library.ML: the following selectors on type 'a option are
  5487 available:
  5488 
  5489   the:               'a option -> 'a  (*partial*)
  5490   these:             'a option -> 'a  where 'a = 'b list
  5491   the_default: 'a -> 'a option -> 'a
  5492   the_list:          'a option -> 'a list
  5493 
  5494 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5495 basic operations for association lists, following natural argument
  5496 order; moreover the explicit equality predicate passed here avoids
  5497 potentially expensive polymorphic runtime equality checks.
  5498 The old functions may be expressed as follows:
  5499 
  5500   assoc = uncurry (AList.lookup (op =))
  5501   assocs = these oo AList.lookup (op =)
  5502   overwrite = uncurry (AList.update (op =)) o swap
  5503 
  5504 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5505 
  5506   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5507   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5508 
  5509 replacing make_keylist and keyfilter (occassionally used)
  5510 Naive rewrites:
  5511 
  5512   make_keylist = AList.make
  5513   keyfilter = AList.find (op =)
  5514 
  5515 * eq_fst and eq_snd now take explicit equality parameter, thus
  5516   avoiding eqtypes. Naive rewrites:
  5517 
  5518     eq_fst = eq_fst (op =)
  5519     eq_snd = eq_snd (op =)
  5520 
  5521 * Removed deprecated apl and apr (rarely used).
  5522   Naive rewrites:
  5523 
  5524     apl (n, op) =>>= curry op n
  5525     apr (op, m) =>>= fn n => op (n, m)
  5526 
  5527 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5528 provides a reasonably efficient light-weight implementation of sets as
  5529 lists.
  5530 
  5531 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5532 few new operations; existing lookup and update are now curried to
  5533 follow natural argument order (for use with fold etc.);
  5534 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5535 
  5536 * Pure/General: output via the Isabelle channels of
  5537 writeln/warning/error etc. is now passed through Output.output, with a
  5538 hook for arbitrary transformations depending on the print_mode
  5539 (cf. Output.add_mode -- the first active mode that provides a output
  5540 function wins).  Already formatted output may be embedded into further
  5541 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5542 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5543 accommodate easy composition of diagnostic messages etc.  Programmers
  5544 rarely need to care about Output.output or Output.raw at all, with
  5545 some notable exceptions: Output.output is required when bypassing the
  5546 standard channels (writeln etc.), or in token translations to produce
  5547 properly formatted results; Output.raw is required when capturing
  5548 already output material that will eventually be presented to the user
  5549 a second time.  For the default print mode, both Output.output and
  5550 Output.raw have no effect.
  5551 
  5552 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5553 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5554 cumulative results are displayed at the end of a batch session.
  5555 
  5556 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5557 replaced by File.platform_path and File.shell_path (with appropriate
  5558 hooks).  This provides a clean interface for unusual systems where the
  5559 internal and external process view of file names are different.
  5560 
  5561 * Pure: more efficient orders for basic syntactic entities: added
  5562 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5563 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5564 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5565 orders now -- potential INCOMPATIBILITY for code that depends on a
  5566 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5567 Library.sort_strings on result).
  5568 
  5569 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5570 fold_types traverse types/terms from left to right, observing natural
  5571 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5572 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5573 
  5574 * Pure: name spaces have been refined, with significant changes of the
  5575 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5576 to extern(_table).  The plain name entry path is superceded by a
  5577 general 'naming' context, which also includes the 'policy' to produce
  5578 a fully qualified name and external accesses of a fully qualified
  5579 name; NameSpace.extend is superceded by context dependent
  5580 Sign.declare_name.  Several theory and proof context operations modify
  5581 the naming context.  Especially note Theory.restore_naming and
  5582 ProofContext.restore_naming to get back to a sane state; note that
  5583 Theory.add_path is no longer sufficient to recover from
  5584 Theory.absolute_path in particular.
  5585 
  5586 * Pure: new flags short_names (default false) and unique_names
  5587 (default true) for controlling output of qualified names.  If
  5588 short_names is set, names are printed unqualified.  If unique_names is
  5589 reset, the name prefix is reduced to the minimum required to achieve
  5590 the original result when interning again, even if there is an overlap
  5591 with earlier declarations.
  5592 
  5593 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5594 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5595 (useful for printing error messages).  INCOMPATIBILITY.
  5596 
  5597 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5598 Theory.theory are now identified, referring to the universal
  5599 Context.theory (see Pure/context.ML).  Actual signature and theory
  5600 content is managed as theory data.  The old code and interfaces were
  5601 spread over many files and structures; the new arrangement introduces
  5602 considerable INCOMPATIBILITY to gain more clarity:
  5603 
  5604   Context -- theory management operations (name, identity, inclusion,
  5605     parents, ancestors, merge, etc.), plus generic theory data;
  5606 
  5607   Sign -- logical signature and syntax operations (declaring consts,
  5608     types, etc.), plus certify/read for common entities;
  5609 
  5610   Theory -- logical theory operations (stating axioms, definitions,
  5611     oracles), plus a copy of logical signature operations (consts,
  5612     types, etc.); also a few basic management operations (Theory.copy,
  5613     Theory.merge, etc.)
  5614 
  5615 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5616 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5617 for convenience -- they merely return the theory.
  5618 
  5619 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5620 
  5621 * Pure: the Isar proof context type is already defined early in Pure
  5622 as Context.proof (note that ProofContext.context and Proof.context are
  5623 aliases, where the latter is the preferred name).  This enables other
  5624 Isabelle components to refer to that type even before Isar is present.
  5625 
  5626 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5627 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5628 any of these kinds.  For example, Sign.intern typeK is now
  5629 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5630 Theory.hide_types.  Also note that former
  5631 Theory.hide_classes/types/consts are now
  5632 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5633 internalize their arguments!  INCOMPATIBILITY.
  5634 
  5635 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5636 datatype thmref (with constructors Name and NameSelection) instead of
  5637 plain string -- INCOMPATIBILITY;
  5638 
  5639 * Pure: cases produced by proof methods specify options, where NONE
  5640 means to remove case bindings -- INCOMPATIBILITY in
  5641 (RAW_)METHOD_CASES.
  5642 
  5643 * Pure: the following operations retrieve axioms or theorems from a
  5644 theory node or theory hierarchy, respectively:
  5645 
  5646   Theory.axioms_of: theory -> (string * term) list
  5647   Theory.all_axioms_of: theory -> (string * term) list
  5648   PureThy.thms_of: theory -> (string * thm) list
  5649   PureThy.all_thms_of: theory -> (string * thm) list
  5650 
  5651 * Pure: print_tac now outputs the goal through the trace channel.
  5652 
  5653 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5654 Reference Toplevel.debug (default false) controls detailed printing
  5655 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5656 controls execution profiling -- set to 1 for time and 2 for space
  5657 (both increase the runtime).
  5658 
  5659 * Isar session: The initial use of ROOT.ML is now always timed,
  5660 i.e. the log will show the actual process times, in contrast to the
  5661 elapsed wall-clock time that the outer shell wrapper produces.
  5662 
  5663 * Simplifier: improved handling of bound variables (nameless
  5664 representation, avoid allocating new strings).  Simprocs that invoke
  5665 the Simplifier recursively should use Simplifier.inherit_bounds to
  5666 avoid local name clashes.  Failure to do so produces warnings
  5667 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5668 for further details.
  5669 
  5670 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5671 bindings for all theorems stored within a given theory; this may help
  5672 in porting non-Isar theories to Isar ones, while keeping ML proof
  5673 scripts for the time being.
  5674 
  5675 * ML operator HTML.with_charset specifies the charset begin used for
  5676 generated HTML files.  For example:
  5677 
  5678   HTML.with_charset "utf-8" use_thy "Hebrew";
  5679   HTML.with_charset "utf-8" use_thy "Chinese";
  5680 
  5681 
  5682 *** System ***
  5683 
  5684 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5685 isabelle, isatool etc.).
  5686 
  5687 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5688 isatool doc, isatool mkdir, display_drafts etc.).
  5689 
  5690 * isatool usedir: option -f allows specification of the ML file to be
  5691 used by Isabelle; default is ROOT.ML.
  5692 
  5693 * New isatool version outputs the version identifier of the Isabelle
  5694 distribution being used.
  5695 
  5696 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5697 (containing Boolean satisfiability problems) into Isabelle/HOL
  5698 theories.
  5699 
  5700 
  5701 
  5702 New in Isabelle2004 (April 2004)
  5703 --------------------------------
  5704 
  5705 *** General ***
  5706 
  5707 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5708   Replaces linorder.ML.
  5709 
  5710 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5711   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5712   (\<a>...\<z>), are now considered normal letters, and can therefore
  5713   be used anywhere where an ASCII letter (a...zA...Z) has until
  5714   now. COMPATIBILITY: This obviously changes the parsing of some
  5715   terms, especially where a symbol has been used as a binder, say
  5716   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5717   as an identifier.  Fix it by inserting a space around former
  5718   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5719   existing theory and ML files.
  5720 
  5721 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5722 
  5723 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5724   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5725   a normal (but invisible) letter. For multiple letter subscripts repeat
  5726   \<^isub> like this: x\<^isub>1\<^isub>2.
  5727 
  5728 * Pure: There are now sub-/superscripts that can span more than one
  5729   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5730   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5731   superscript. The new control characters are not identifier parts.
  5732 
  5733 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5734   content of "..." to the latex file instead of \isacntrl... . The "..."
  5735   may consist of any printable characters excluding the end bracket >.
  5736 
  5737 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5738   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5739   declare constants "final", which prevents their being given a definition
  5740   later.  It is useful for constants whose behaviour is fixed axiomatically
  5741   rather than definitionally, such as the meta-logic connectives.
  5742 
  5743 * Pure: 'instance' now handles general arities with general sorts
  5744   (i.e. intersections of classes),
  5745 
  5746 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5747   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5748   It can be changed to alter the colors/layout of generated pages.
  5749 
  5750 
  5751 *** Isar ***
  5752 
  5753 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5754   cut_tac, subgoal_tac and thin_tac:
  5755   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5756     locales are no longer forced to write Isar proof scripts.
  5757     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5758     emulations.
  5759   - INCOMPATIBILITY: names of variables to be instantiated may no
  5760     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5761     This is consistent with the instantiation attribute "where".
  5762 
  5763 * Attributes "where" and "of":
  5764   - Now take type variables of instantiated theorem into account when reading
  5765     the instantiation string.  This fixes a bug that caused instantiated
  5766     theorems to have too special types in some circumstances.
  5767   - "where" permits explicit instantiations of type variables.
  5768 
  5769 * Calculation commands "moreover" and "also" no longer interfere with
  5770   current facts ("this"), admitting arbitrary combinations with "then"
  5771   and derived forms.
  5772 
  5773 * Locales:
  5774   - Goal statements involving the context element "includes" no longer
  5775     generate theorems with internal delta predicates (those ending on
  5776     "_axioms") in the premise.
  5777     Resolve particular premise with <locale>.intro to obtain old form.
  5778   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5779     specification and "includes" elements in goal statement.
  5780   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5781     [intro?] and [elim?] (respectively) by default.
  5782   - Experimental command for instantiation of locales in proof contexts:
  5783         instantiate <label>[<attrs>]: <loc>
  5784     Instantiates locale <loc> and adds all its theorems to the current context
  5785     taking into account their attributes.  Label and attrs are optional
  5786     modifiers, like in theorem declarations.  If present, names of
  5787     instantiated theorems are qualified with <label>, and the attributes
  5788     <attrs> are applied after any attributes these theorems might have already.
  5789       If the locale has assumptions, a chained fact of the form
  5790     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5791     are derived.  The command does not support old-style locales declared
  5792     with "locale (open)".
  5793       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5794 
  5795 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5796   (Isar) contexts.
  5797 
  5798 
  5799 *** HOL ***
  5800 
  5801 * Proof import: new image HOL4 contains the imported library from
  5802   the HOL4 system with about 2500 theorems. It is imported by
  5803   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5804   can be used like any other Isabelle image.  See
  5805   HOL/Import/HOL/README for more information.
  5806 
  5807 * Simplifier:
  5808   - Much improved handling of linear and partial orders.
  5809     Reasoners for linear and partial orders are set up for type classes
  5810     "linorder" and "order" respectively, and are added to the default simpset
  5811     as solvers.  This means that the simplifier can build transitivity chains
  5812     to solve goals from the assumptions.
  5813   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5814     of blast or auto after simplification become unnecessary because the goal
  5815     is solved by simplification already.
  5816 
  5817 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5818     all proved in axiomatic type classes for semirings, rings and fields.
  5819 
  5820 * Numerics:
  5821   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5822     now formalized using the Ring_and_Field theory mentioned above.
  5823   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5824     than before, because now they are set up once in a generic manner.
  5825   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5826     Look for the general versions in Ring_and_Field (and Power if they concern
  5827     exponentiation).
  5828 
  5829 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5830 
  5831 * Records:
  5832   - Record types are now by default printed with their type abbreviation
  5833     instead of the list of all field types. This can be configured via
  5834     the reference "print_record_type_abbr".
  5835   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5836     (not enabled by default).
  5837   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5838     EX x. x = sel r to True (not enabled by default).
  5839   - Tactic "record_split_simp_tac" to split and simplify records added.
  5840 
  5841 * 'specification' command added, allowing for definition by
  5842   specification.  There is also an 'ax_specification' command that
  5843   introduces the new constants axiomatically.
  5844 
  5845 * arith(_tac) is now able to generate counterexamples for reals as well.
  5846 
  5847 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5848 
  5849 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5850   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5851 
  5852 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5853   matrix theory to linear programming.
  5854 
  5855 * Unions and Intersections:
  5856   The latex output syntax of UN and INT has been changed
  5857   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5858   i.e. the index formulae has become a subscript.
  5859   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5860 
  5861 * Unions and Intersections over Intervals:
  5862   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5863   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5864   like in normal math, and corresponding versions for < and for intersection.
  5865 
  5866 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5867   lexicographic dictonary ordering has been added as "lexord".
  5868 
  5869 * ML: the legacy theory structures Int and List have been removed. They had
  5870   conflicted with ML Basis Library structures having the same names.
  5871 
  5872 * 'refute' command added to search for (finite) countermodels.  Only works
  5873   for a fragment of HOL.  The installation of an external SAT solver is
  5874   highly recommended.  See "HOL/Refute.thy" for details.
  5875 
  5876 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5877   formulae under an assignment of free variables to random values.
  5878   In contrast to 'refute', it can deal with inductive datatypes,
  5879   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5880   for examples.
  5881 
  5882 
  5883 *** HOLCF ***
  5884 
  5885 * Streams now come with concatenation and are part of the HOLCF image
  5886 
  5887 
  5888 
  5889 New in Isabelle2003 (May 2003)
  5890 ------------------------------
  5891 
  5892 *** General ***
  5893 
  5894 * Provers/simplifier:
  5895 
  5896   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5897     Assumptions are now subject to complete mutual simplification,
  5898     not just from left to right. The simplifier now preserves
  5899     the order of assumptions.
  5900 
  5901     Potential INCOMPATIBILITY:
  5902 
  5903     -- simp sometimes diverges where the old version did
  5904        not, e.g. invoking simp on the goal
  5905 
  5906         [| P (f x); y = x; f x = f y |] ==> Q
  5907 
  5908        now gives rise to the infinite reduction sequence
  5909 
  5910         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5911 
  5912        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5913        kind of problem.
  5914 
  5915     -- Tactics combining classical reasoner and simplification (such as auto)
  5916        are also affected by this change, because many of them rely on
  5917        simp. They may sometimes diverge as well or yield a different numbers
  5918        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5919        in case of problems. Sometimes subsequent calls to the classical
  5920        reasoner will fail because a preceeding call to the simplifier too
  5921        eagerly simplified the goal, e.g. deleted redundant premises.
  5922 
  5923   - The simplifier trace now shows the names of the applied rewrite rules
  5924 
  5925   - You can limit the number of recursive invocations of the simplifier
  5926     during conditional rewriting (where the simplifie tries to solve the
  5927     conditions before applying the rewrite rule):
  5928     ML "simp_depth_limit := n"
  5929     where n is an integer. Thus you can force termination where previously
  5930     the simplifier would diverge.
  5931 
  5932   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5933 
  5934   - No longer aborts on failed congruence proof.  Instead, the
  5935     congruence is ignored.
  5936 
  5937 * Pure: New generic framework for extracting programs from constructive
  5938   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5939   as HOL/Extraction for some case studies.
  5940 
  5941 * Pure: The main goal of the proof state is no longer shown by default, only
  5942 the subgoals. This behaviour is controlled by a new flag.
  5943    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5944 (ML: Proof.show_main_goal).
  5945 
  5946 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5947 rules whose conclusion matches subgoal 1:
  5948       PG menu: Isabelle/Isar -> Show me -> matching rules
  5949 The rules are ordered by how closely they match the subgoal.
  5950 In particular, rules that solve a subgoal outright are displayed first
  5951 (or rather last, the way they are printed).
  5952 (ML: ProofGeneral.print_intros())
  5953 
  5954 * Pure: New flag trace_unify_fail causes unification to print
  5955 diagnostic information (PG: in trace buffer) when it fails. This is
  5956 useful for figuring out why single step proofs like rule, erule or
  5957 assumption failed.
  5958 
  5959 * Pure: Locale specifications now produce predicate definitions
  5960 according to the body of text (covering assumptions modulo local
  5961 definitions); predicate "loc_axioms" covers newly introduced text,
  5962 while "loc" is cumulative wrt. all included locale expressions; the
  5963 latter view is presented only on export into the global theory
  5964 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5965 on the old view without predicates;
  5966 
  5967 * Pure: predefined locales "var" and "struct" are useful for sharing
  5968 parameters (as in CASL, for example); just specify something like
  5969 ``var x + var y + struct M'' as import;
  5970 
  5971 * Pure: improved thms_containing: proper indexing of facts instead of
  5972 raw theorems; check validity of results wrt. current name space;
  5973 include local facts of proof configuration (also covers active
  5974 locales), cover fixed variables in index; may use "_" in term
  5975 specification; an optional limit for the number of printed facts may
  5976 be given (the default is 40);
  5977 
  5978 * Pure: disallow duplicate fact bindings within new-style theory files
  5979 (batch-mode only);
  5980 
  5981 * Provers: improved induct method: assumptions introduced by case
  5982 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5983 the goal statement); "foo" still refers to all facts collectively;
  5984 
  5985 * Provers: the function blast.overloaded has been removed: all constants
  5986 are regarded as potentially overloaded, which improves robustness in exchange
  5987 for slight decrease in efficiency;
  5988 
  5989 * Provers/linorder: New generic prover for transitivity reasoning over
  5990 linear orders.  Note: this prover is not efficient!
  5991 
  5992 * Isar: preview of problems to finish 'show' now produce an error
  5993 rather than just a warning (in interactive mode);
  5994 
  5995 
  5996 *** HOL ***
  5997 
  5998 * arith(_tac)
  5999 
  6000  - Produces a counter example if it cannot prove a goal.
  6001    Note that the counter example may be spurious if the goal is not a formula
  6002    of quantifier-free linear arithmetic.
  6003    In ProofGeneral the counter example appears in the trace buffer.
  6004 
  6005  - Knows about div k and mod k where k is a numeral of type nat or int.
  6006 
  6007  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  6008    linear arithmetic fails. This takes account of quantifiers and divisibility.
  6009    Presburger arithmetic can also be called explicitly via presburger(_tac).
  6010 
  6011 * simp's arithmetic capabilities have been enhanced a bit: it now
  6012 takes ~= in premises into account (by performing a case split);
  6013 
  6014 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  6015 are distributed over a sum of terms;
  6016 
  6017 * New tactic "trans_tac" and method "trans" instantiate
  6018 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  6019 "<=", "<" and "=").
  6020 
  6021 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  6022 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  6023 
  6024 * 'typedef' command has new option "open" to suppress the set
  6025 definition;
  6026 
  6027 * functions Min and Max on finite sets have been introduced (theory
  6028 Finite_Set);
  6029 
  6030 * attribute [symmetric] now works for relations as well; it turns
  6031 (x,y) : R^-1 into (y,x) : R, and vice versa;
  6032 
  6033 * induct over a !!-quantified statement (say !!x1..xn):
  6034   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  6035 
  6036 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  6037 %x. None. Warning: empty_def now refers to the previously hidden definition
  6038 of the empty set.
  6039 
  6040 * Algebra: formalization of classical algebra.  Intended as base for
  6041 any algebraic development in Isabelle.  Currently covers group theory
  6042 (up to Sylow's theorem) and ring theory (Universal Property of
  6043 Univariate Polynomials).  Contributions welcome;
  6044 
  6045 * GroupTheory: deleted, since its material has been moved to Algebra;
  6046 
  6047 * Complex: new directory of the complex numbers with numeric constants,
  6048 nonstandard complex numbers, and some complex analysis, standard and
  6049 nonstandard (Jacques Fleuriot);
  6050 
  6051 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  6052 
  6053 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  6054 Fleuriot);
  6055 
  6056 * Real/HahnBanach: updated and adapted to locales;
  6057 
  6058 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  6059 Gray and Kramer);
  6060 
  6061 * UNITY: added the Meier-Sanders theory of progress sets;
  6062 
  6063 * MicroJava: bytecode verifier and lightweight bytecode verifier
  6064 as abstract algorithms, instantiated to the JVM;
  6065 
  6066 * Bali: Java source language formalization. Type system, operational
  6067 semantics, axiomatic semantics. Supported language features:
  6068 classes, interfaces, objects,virtual methods, static methods,
  6069 static/instance fields, arrays, access modifiers, definite
  6070 assignment, exceptions.
  6071 
  6072 
  6073 *** ZF ***
  6074 
  6075 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  6076 universe, etc.);
  6077 
  6078 * Main ZF: virtually all theories converted to new-style format;
  6079 
  6080 
  6081 *** ML ***
  6082 
  6083 * Pure: Tactic.prove provides sane interface for internal proofs;
  6084 omits the infamous "standard" operation, so this is more appropriate
  6085 than prove_goalw_cterm in many situations (e.g. in simprocs);
  6086 
  6087 * Pure: improved error reporting of simprocs;
  6088 
  6089 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  6090 up simprocs;
  6091 
  6092 
  6093 *** Document preparation ***
  6094 
  6095 * uses \par instead of \\ for line breaks in theory text. This may
  6096 shift some page breaks in large documents. To get the old behaviour
  6097 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  6098 
  6099 * minimized dependencies of isabelle.sty and isabellesym.sty on
  6100 other packages
  6101 
  6102 * \<euro> now needs package babel/greek instead of marvosym (which
  6103 broke \Rightarrow)
  6104 
  6105 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  6106 textcomp package)
  6107 
  6108 
  6109 
  6110 New in Isabelle2002 (March 2002)
  6111 --------------------------------
  6112 
  6113 *** Document preparation ***
  6114 
  6115 * greatly simplified document preparation setup, including more
  6116 graceful interpretation of isatool usedir -i/-d/-D options, and more
  6117 instructive isatool mkdir; users should basically be able to get
  6118 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  6119 users may run a separate document processing stage manually like this:
  6120 "isatool usedir -D output HOL Test && isatool document Test/output";
  6121 
  6122 * theory dependency graph may now be incorporated into documents;
  6123 isatool usedir -g true will produce session_graph.eps/.pdf for use
  6124 with \includegraphics of LaTeX;
  6125 
  6126 * proper spacing of consecutive markup elements, especially text
  6127 blocks after section headings;
  6128 
  6129 * support bold style (for single symbols only), input syntax is like
  6130 this: "\<^bold>\<alpha>" or "\<^bold>A";
  6131 
  6132 * \<bullet> is now output as bold \cdot by default, which looks much
  6133 better in printed text;
  6134 
  6135 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  6136 note that these symbols are currently unavailable in Proof General /
  6137 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  6138 
  6139 * isatool latex no longer depends on changed TEXINPUTS, instead
  6140 isatool document copies the Isabelle style files to the target
  6141 location;
  6142 
  6143 
  6144 *** Isar ***
  6145 
  6146 * Pure/Provers: improved proof by cases and induction;
  6147   - 'case' command admits impromptu naming of parameters (such as
  6148     "case (Suc n)");
  6149   - 'induct' method divinates rule instantiation from the inductive
  6150     claim; no longer requires excessive ?P bindings for proper
  6151     instantiation of cases;
  6152   - 'induct' method properly enumerates all possibilities of set/type
  6153     rules; as a consequence facts may be also passed through *type*
  6154     rules without further ado;
  6155   - 'induct' method now derives symbolic cases from the *rulified*
  6156     rule (before it used to rulify cases stemming from the internal
  6157     atomized version); this means that the context of a non-atomic
  6158     statement becomes is included in the hypothesis, avoiding the
  6159     slightly cumbersome show "PROP ?case" form;
  6160   - 'induct' may now use elim-style induction rules without chaining
  6161     facts, using ``missing'' premises from the goal state; this allows
  6162     rules stemming from inductive sets to be applied in unstructured
  6163     scripts, while still benefitting from proper handling of non-atomic
  6164     statements; NB: major inductive premises need to be put first, all
  6165     the rest of the goal is passed through the induction;
  6166   - 'induct' proper support for mutual induction involving non-atomic
  6167     rule statements (uses the new concept of simultaneous goals, see
  6168     below);
  6169   - append all possible rule selections, but only use the first
  6170     success (no backtracking);
  6171   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  6172   - undeclared rule case names default to numbers 1, 2, 3, ...;
  6173   - added 'print_induct_rules' (covered by help item in recent Proof
  6174     General versions);
  6175   - moved induct/cases attributes to Pure, methods to Provers;
  6176   - generic method setup instantiated for FOL and HOL;
  6177 
  6178 * Pure: support multiple simultaneous goal statements, for example
  6179 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  6180 meta-level mechanism, this acts as if several individual goals had
  6181 been stated separately; in particular common proof methods need to be
  6182 repeated in order to cover all claims; note that a single elimination
  6183 step is *not* sufficient to establish the two conjunctions, so this
  6184 fails:
  6185 
  6186   assume "A & B" then have A and B ..   (*".." fails*)
  6187 
  6188 better use "obtain" in situations as above; alternative refer to
  6189 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  6190 
  6191 * Pure: proper integration with ``locales''; unlike the original
  6192 version by Florian Kammller, Isar locales package high-level proof
  6193 contexts rather than raw logical ones (e.g. we admit to include
  6194 attributes everywhere); operations on locales include merge and
  6195 rename; support for implicit arguments (``structures''); simultaneous
  6196 type-inference over imports and text; see also HOL/ex/Locales.thy for
  6197 some examples;
  6198 
  6199 * Pure: the following commands have been ``localized'', supporting a
  6200 target locale specification "(in name)": 'lemma', 'theorem',
  6201 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  6202 stored both within the locale and at the theory level (exported and
  6203 qualified by the locale name);
  6204 
  6205 * Pure: theory goals may now be specified in ``long'' form, with
  6206 ad-hoc contexts consisting of arbitrary locale elements. for example
  6207 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  6208 definitions may be given, too); the result is a meta-level rule with
  6209 the context elements being discharged in the obvious way;
  6210 
  6211 * Pure: new proof command 'using' allows to augment currently used
  6212 facts after a goal statement ('using' is syntactically analogous to
  6213 'apply', but acts on the goal's facts only); this allows chained facts
  6214 to be separated into parts given before and after a claim, as in
  6215 ``from a and b have C using d and e <proof>'';
  6216 
  6217 * Pure: renamed "antecedent" case to "rule_context";
  6218 
  6219 * Pure: new 'judgment' command records explicit information about the
  6220 object-logic embedding (used by several tools internally); no longer
  6221 use hard-wired "Trueprop";
  6222 
  6223 * Pure: added 'corollary' command;
  6224 
  6225 * Pure: fixed 'token_translation' command;
  6226 
  6227 * Pure: removed obsolete 'exported' attribute;
  6228 
  6229 * Pure: dummy pattern "_" in is/let is now automatically lifted over