NEWS
author haftmann
Mon Aug 08 19:21:11 2011 +0200 (2011-08-08)
changeset 44082 81e55342cb86
parent 44027 d01b3f045111
child 44086 c0847967a25a
permissions -rw-r--r--
dropped lemmas (Inf|Sup)_(singleton|binary)
     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 
   176 *** Document preparation ***
   177 
   178 * Discontinued special treatment of hard tabulators, which are better
   179 avoided in the first place.  Implicit tab-width is 1.
   180 
   181 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
   182 isar-ref manual.
   183 
   184 * Antiquotation @{value} evaluates the given term and presents its result.
   185 
   186 * Localized \isabellestyle switch can be used within blocks or groups
   187 like this:
   188 
   189   \isabellestyle{it}  %preferred default
   190   {\isabellestylett @{text "typewriter stuff"}}
   191 
   192 * New term style "isub" as ad-hoc conversion of variables x1, y23 into
   193 subscripted form x\<^isub>1, y\<^isub>2\<^isub>3.
   194 
   195 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
   196 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
   197 
   198 
   199 *** ML ***
   200 
   201 * The inner syntax of sort/type/term/prop supports inlined YXML
   202 representations within quoted string tokens.  By encoding logical
   203 entities via Term_XML (in ML or Scala) concrete syntax can be
   204 bypassed, which is particularly useful for producing bits of text
   205 under external program control.
   206 
   207 * Antiquotations for ML and document preparation are managed as theory
   208 data, which requires explicit setup.
   209 
   210 * Isabelle_Process.is_active allows tools to check if the official
   211 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
   212 (better known as Proof General).
   213 
   214 * Structure Proof_Context follows standard naming scheme.  Old
   215 ProofContext is still available for some time as legacy alias.
   216 
   217 * Structure Timing provides various operations for timing; supersedes
   218 former start_timing/end_timing etc.
   219 
   220 * Path.print is the official way to show file-system paths to users
   221 (including quotes etc.).
   222 
   223 * Inner syntax: identifiers in parse trees of generic categories
   224 "logic", "aprop", "idt" etc. carry position information (disguised as
   225 type constraints).  Occasional INCOMPATIBILITY with non-compliant
   226 translations that choke on unexpected type constraints.  Positions can
   227 be stripped in ML translations via Syntax.strip_positions /
   228 Syntax.strip_positions_ast, or via the syntax constant
   229 "_strip_positions" within parse trees.  As last resort, positions can
   230 be disabled via the configuration option Syntax.positions, which is
   231 called "syntax_positions" in Isar attribute syntax.
   232 
   233 * Discontinued special status of various ML structures that contribute
   234 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
   235 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
   236 refer directly to Ast.Constant, Lexicon.is_identifier,
   237 Syntax_Trans.mk_binder_tr etc.
   238 
   239 * Typed print translation: discontinued show_sorts argument, which is
   240 already available via context of "advanced" translation.
   241 
   242 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
   243 goal states; body tactic needs to address all subgoals uniformly.
   244 
   245 * Slightly more special eq_list/eq_set, with shortcut involving
   246 pointer equality (assumes that eq relation is reflexive).
   247 
   248 * Classical tactics use proper Proof.context instead of historic types
   249 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
   250 operate directly on Proof.context.  Raw type claset retains its use as
   251 snapshot of the classical context, which can be recovered via
   252 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
   253 INCOMPATIBILITY, classical tactics and derived proof methods require
   254 proper Proof.context.
   255 
   256 * Scala layer provides JVM method invocation service for static
   257 methods of type (String)String, see Invoke_Scala.method in ML.
   258 For example:
   259 
   260   Invoke_Scala.method "java.lang.System.getProperty" "java.home"
   261 
   262 
   263 
   264 New in Isabelle2011 (January 2011)
   265 ----------------------------------
   266 
   267 *** General ***
   268 
   269 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
   270 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
   271 useful tooltips and hyperlinks produced from its static analysis.  The
   272 bundled component provides an executable Isabelle tool that can be run
   273 like this:
   274 
   275   Isabelle2011/bin/isabelle jedit
   276 
   277 * Significantly improved Isabelle/Isar implementation manual.
   278 
   279 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
   280 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
   281 while the default heap location within that directory lacks that extra
   282 suffix.  This isolates multiple Isabelle installations from each
   283 other, avoiding problems with old settings in new versions.
   284 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
   285 
   286 * Source files are always encoded as UTF-8, instead of old-fashioned
   287 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   288 the following package declarations:
   289 
   290   \usepackage[utf8]{inputenc}
   291   \usepackage{textcomp}
   292 
   293 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   294 a Unicode character is treated as a single symbol, not a sequence of
   295 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   296 contain symbols without further backslash escapes, Unicode can now be
   297 used here as well.  Recall that Symbol.explode in ML provides a
   298 consistent view on symbols, while raw explode (or String.explode)
   299 merely give a byte-oriented representation.
   300 
   301 * Theory loader: source files are primarily located via the master
   302 directory of each theory node (where the .thy file itself resides).
   303 The global load path is still partially available as legacy feature.
   304 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   305 explicit paths, relatively to the theory.
   306 
   307 * Special treatment of ML file names has been discontinued.
   308 Historically, optional extensions .ML or .sml were added on demand --
   309 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   310 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   311 
   312 * Various options that affect pretty printing etc. are now properly
   313 handled within the context via configuration options, instead of
   314 unsynchronized references or print modes.  There are both ML Config.T
   315 entities and Isar declaration attributes to access these.
   316 
   317   ML (Config.T)                 Isar (attribute)
   318 
   319   eta_contract                  eta_contract
   320   show_brackets                 show_brackets
   321   show_sorts                    show_sorts
   322   show_types                    show_types
   323   show_question_marks           show_question_marks
   324   show_consts                   show_consts
   325   show_abbrevs                  show_abbrevs
   326 
   327   Syntax.ast_trace              syntax_ast_trace
   328   Syntax.ast_stat               syntax_ast_stat
   329   Syntax.ambiguity_level        syntax_ambiguity_level
   330 
   331   Goal_Display.goals_limit      goals_limit
   332   Goal_Display.show_main_goal   show_main_goal
   333 
   334   Method.rule_trace             rule_trace
   335 
   336   Thy_Output.display            thy_output_display
   337   Thy_Output.quotes             thy_output_quotes
   338   Thy_Output.indent             thy_output_indent
   339   Thy_Output.source             thy_output_source
   340   Thy_Output.break              thy_output_break
   341 
   342 Note that corresponding "..._default" references in ML may only be
   343 changed globally at the ROOT session setup, but *not* within a theory.
   344 The option "show_abbrevs" supersedes the former print mode
   345 "no_abbrevs" with inverted meaning.
   346 
   347 * More systematic naming of some configuration options.
   348 INCOMPATIBILITY.
   349 
   350   trace_simp  ~>  simp_trace
   351   debug_simp  ~>  simp_debug
   352 
   353 * Support for real valued configuration options, using simplistic
   354 floating-point notation that coincides with the inner syntax for
   355 float_token.
   356 
   357 * Support for real valued preferences (with approximative PGIP type):
   358 front-ends need to accept "pgint" values in float notation.
   359 INCOMPATIBILITY.
   360 
   361 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   362 DejaVu Sans.
   363 
   364 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   365 
   366 
   367 *** Pure ***
   368 
   369 * Command 'type_synonym' (with single argument) replaces somewhat
   370 outdated 'types', which is still available as legacy feature for some
   371 time.
   372 
   373 * Command 'nonterminal' (with 'and' separated list of arguments)
   374 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   375 
   376 * Command 'notepad' replaces former 'example_proof' for
   377 experimentation in Isar without any result.  INCOMPATIBILITY.
   378 
   379 * Locale interpretation commands 'interpret' and 'sublocale' accept
   380 lists of equations to map definitions in a locale to appropriate
   381 entities in the context of the interpretation.  The 'interpretation'
   382 command already provided this functionality.
   383 
   384 * Diagnostic command 'print_dependencies' prints the locale instances
   385 that would be activated if the specified expression was interpreted in
   386 the current context.  Variant "print_dependencies!" assumes a context
   387 without interpretations.
   388 
   389 * Diagnostic command 'print_interps' prints interpretations in proofs
   390 in addition to interpretations in theories.
   391 
   392 * Discontinued obsolete 'global' and 'local' commands to manipulate
   393 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   394 Sign.root_path and Sign.local_path may be applied directly where this
   395 feature is still required for historical reasons.
   396 
   397 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   398 'definition' instead.
   399 
   400 * The "prems" fact, which refers to the accidental collection of
   401 foundational premises in the context, is now explicitly marked as
   402 legacy feature and will be discontinued soon.  Consider using "assms"
   403 of the head statement or reference facts by explicit names.
   404 
   405 * Document antiquotations @{class} and @{type} print classes and type
   406 constructors.
   407 
   408 * Document antiquotation @{file} checks file/directory entries within
   409 the local file system.
   410 
   411 
   412 *** HOL ***
   413 
   414 * Coercive subtyping: functions can be declared as coercions and type
   415 inference will add them as necessary upon input of a term.  Theory
   416 Complex_Main declares real :: nat => real and real :: int => real as
   417 coercions. A coercion function f is declared like this:
   418 
   419   declare [[coercion f]]
   420 
   421 To lift coercions through type constructors (e.g. from nat => real to
   422 nat list => real list), map functions can be declared, e.g.
   423 
   424   declare [[coercion_map map]]
   425 
   426 Currently coercion inference is activated only in theories including
   427 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   428 the configuration option "coercion_enabled", e.g. it can be enabled in
   429 other theories like this:
   430 
   431   declare [[coercion_enabled]]
   432 
   433 * Command 'partial_function' provides basic support for recursive
   434 function definitions over complete partial orders.  Concrete instances
   435 are provided for i) the option type, ii) tail recursion on arbitrary
   436 types, and iii) the heap monad of Imperative_HOL.  See
   437 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   438 for examples.
   439 
   440 * Function package: f.psimps rules are no longer implicitly declared
   441 as [simp].  INCOMPATIBILITY.
   442 
   443 * Datatype package: theorems generated for executable equality (class
   444 "eq") carry proper names and are treated as default code equations.
   445 
   446 * Inductive package: now offers command 'inductive_simps' to
   447 automatically derive instantiated and simplified equations for
   448 inductive predicates, similar to 'inductive_cases'.
   449 
   450 * Command 'enriched_type' allows to register properties of the
   451 functorial structure of types.
   452 
   453 * Improved infrastructure for term evaluation using code generator
   454 techniques, in particular static evaluation conversions.
   455 
   456 * Code generator: Scala (2.8 or higher) has been added to the target
   457 languages.
   458 
   459 * Code generator: globbing constant expressions "*" and "Theory.*"
   460 have been replaced by the more idiomatic "_" and "Theory._".
   461 INCOMPATIBILITY.
   462 
   463 * Code generator: export_code without explicit file declaration prints
   464 to standard output.  INCOMPATIBILITY.
   465 
   466 * Code generator: do not print function definitions for case
   467 combinators any longer.
   468 
   469 * Code generator: simplification with rules determined with
   470 src/Tools/Code/code_simp.ML and method "code_simp".
   471 
   472 * Code generator for records: more idiomatic representation of record
   473 types.  Warning: records are not covered by ancient SML code
   474 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   475 rep_datatype declaration helps to succeed then:
   476 
   477   record 'a foo = ...
   478   ...
   479   rep_datatype foo_ext ...
   480 
   481 * Records: logical foundation type for records does not carry a
   482 '_type' suffix any longer (obsolete due to authentic syntax).
   483 INCOMPATIBILITY.
   484 
   485 * Quickcheck now by default uses exhaustive testing instead of random
   486 testing.  Random testing can be invoked by "quickcheck [random]",
   487 exhaustive testing by "quickcheck [exhaustive]".
   488 
   489 * Quickcheck instantiates polymorphic types with small finite
   490 datatypes by default. This enables a simple execution mechanism to
   491 handle quantifiers and function equality over the finite datatypes.
   492 
   493 * Quickcheck random generator has been renamed from "code" to
   494 "random".  INCOMPATIBILITY.
   495 
   496 * Quickcheck now has a configurable time limit which is set to 30
   497 seconds by default. This can be changed by adding [timeout = n] to the
   498 quickcheck command. The time limit for Auto Quickcheck is still set
   499 independently.
   500 
   501 * Quickcheck in locales considers interpretations of that locale for
   502 counter example search.
   503 
   504 * Sledgehammer:
   505   - Added "smt" and "remote_smt" provers based on the "smt" proof
   506     method. See the Sledgehammer manual for details ("isabelle doc
   507     sledgehammer").
   508   - Renamed commands:
   509     sledgehammer atp_info ~> sledgehammer running_provers
   510     sledgehammer atp_kill ~> sledgehammer kill_provers
   511     sledgehammer available_atps ~> sledgehammer available_provers
   512     INCOMPATIBILITY.
   513   - Renamed options:
   514     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   515     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   516     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   517     (and "ms" and "min" are no longer supported)
   518     INCOMPATIBILITY.
   519 
   520 * Nitpick:
   521   - Renamed options:
   522     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   523     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   524     INCOMPATIBILITY.
   525   - Added support for partial quotient types.
   526   - Added local versions of the "Nitpick.register_xxx" functions.
   527   - Added "whack" option.
   528   - Allow registration of quotient types as codatatypes.
   529   - Improved "merge_type_vars" option to merge more types.
   530   - Removed unsound "fast_descrs" option.
   531   - Added custom symmetry breaking for datatypes, making it possible to reach
   532     higher cardinalities.
   533   - Prevent the expansion of too large definitions.
   534 
   535 * Proof methods "metis" and "meson" now have configuration options
   536 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   537 to diagnose these tools. E.g.
   538 
   539     using [[metis_trace = true]]
   540 
   541 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   542 manually as command 'solve_direct'.
   543 
   544 * The default SMT solver Z3 must be enabled explicitly (due to
   545 licensing issues) by setting the environment variable
   546 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   547 commercial applications, the SMT solver CVC3 is provided as fall-back;
   548 changing the SMT solver is done via the configuration option
   549 "smt_solver".
   550 
   551 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   552 i.e. "remote_cvc3" and "remote_z3".
   553 
   554 * Added basic SMT support for datatypes, records, and typedefs using
   555 the oracle mode (no proofs).  Direct support of pairs has been dropped
   556 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   557 support for a similar behavior).  Minor INCOMPATIBILITY.
   558 
   559 * Changed SMT configuration options:
   560   - Renamed:
   561     z3_proofs ~> smt_oracle (with inverted meaning)
   562     z3_trace_assms ~> smt_trace_used_facts
   563     INCOMPATIBILITY.
   564   - Added:
   565     smt_verbose
   566     smt_random_seed
   567     smt_datatypes
   568     smt_infer_triggers
   569     smt_monomorph_limit
   570     cvc3_options
   571     remote_cvc3_options
   572     remote_z3_options
   573     yices_options
   574 
   575 * Boogie output files (.b2i files) need to be declared in the theory
   576 header.
   577 
   578 * Simplification procedure "list_to_set_comprehension" rewrites list
   579 comprehensions applied to List.set to set comprehensions.  Occasional
   580 INCOMPATIBILITY, may be deactivated like this:
   581 
   582   declare [[simproc del: list_to_set_comprehension]]
   583 
   584 * Removed old version of primrec package.  INCOMPATIBILITY.
   585 
   586 * Removed simplifier congruence rule of "prod_case", as has for long
   587 been the case with "split".  INCOMPATIBILITY.
   588 
   589 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   590 
   591 * Removed [split_format ... and ... and ...] version of
   592 [split_format].  Potential INCOMPATIBILITY.
   593 
   594 * Predicate "sorted" now defined inductively, with nice induction
   595 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   596 
   597 * Constant "contents" renamed to "the_elem", to free the generic name
   598 contents for other uses.  INCOMPATIBILITY.
   599 
   600 * Renamed class eq and constant eq (for code generation) to class
   601 equal and constant equal, plus renaming of related facts and various
   602 tuning.  INCOMPATIBILITY.
   603 
   604 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   605 
   606 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   607 INCOMPATIBILITY.
   608 
   609 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   610 avoid confusion with finite sets.  INCOMPATIBILITY.
   611 
   612 * Abandoned locales equiv, congruent and congruent2 for equivalence
   613 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   614 for congruent(2)).
   615 
   616 * Some previously unqualified names have been qualified:
   617 
   618   types
   619     bool ~> HOL.bool
   620     nat ~> Nat.nat
   621 
   622   constants
   623     Trueprop ~> HOL.Trueprop
   624     True ~> HOL.True
   625     False ~> HOL.False
   626     op & ~> HOL.conj
   627     op | ~> HOL.disj
   628     op --> ~> HOL.implies
   629     op = ~> HOL.eq
   630     Not ~> HOL.Not
   631     The ~> HOL.The
   632     All ~> HOL.All
   633     Ex ~> HOL.Ex
   634     Ex1 ~> HOL.Ex1
   635     Let ~> HOL.Let
   636     If ~> HOL.If
   637     Ball ~> Set.Ball
   638     Bex ~> Set.Bex
   639     Suc ~> Nat.Suc
   640     Pair ~> Product_Type.Pair
   641     fst ~> Product_Type.fst
   642     snd ~> Product_Type.snd
   643     curry ~> Product_Type.curry
   644     op : ~> Set.member
   645     Collect ~> Set.Collect
   646 
   647 INCOMPATIBILITY.
   648 
   649 * More canonical naming convention for some fundamental definitions:
   650 
   651     bot_bool_eq ~> bot_bool_def
   652     top_bool_eq ~> top_bool_def
   653     inf_bool_eq ~> inf_bool_def
   654     sup_bool_eq ~> sup_bool_def
   655     bot_fun_eq  ~> bot_fun_def
   656     top_fun_eq  ~> top_fun_def
   657     inf_fun_eq  ~> inf_fun_def
   658     sup_fun_eq  ~> sup_fun_def
   659 
   660 INCOMPATIBILITY.
   661 
   662 * More stylized fact names:
   663 
   664   expand_fun_eq ~> fun_eq_iff
   665   expand_set_eq ~> set_eq_iff
   666   set_ext       ~> set_eqI
   667   nat_number    ~> eval_nat_numeral
   668 
   669 INCOMPATIBILITY.
   670 
   671 * Refactoring of code-generation specific operations in theory List:
   672 
   673   constants
   674     null ~> List.null
   675 
   676   facts
   677     mem_iff ~> member_def
   678     null_empty ~> null_def
   679 
   680 INCOMPATIBILITY.  Note that these were not supposed to be used
   681 regularly unless for striking reasons; their main purpose was code
   682 generation.
   683 
   684 Various operations from the Haskell prelude are used for generating
   685 Haskell code.
   686 
   687 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   688 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   689 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   690 
   691 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   692 "*" and "+" respectively.  INCOMPATIBILITY.
   693 
   694 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   695 "Sum_Type.Plus" instead.
   696 
   697 * Constant "split" has been merged with constant "prod_case"; names of
   698 ML functions, facts etc. involving split have been retained so far,
   699 though.  INCOMPATIBILITY.
   700 
   701 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   702 instead.  INCOMPATIBILITY.
   703 
   704 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   705 INCOMPATIBILITY.
   706 
   707 * Former theory Library/Enum is now part of the HOL-Main image.
   708 INCOMPATIBILITY: all constants of the Enum theory now have to be
   709 referred to by its qualified name.
   710 
   711   enum    ~>  Enum.enum
   712   nlists  ~>  Enum.nlists
   713   product ~>  Enum.product
   714 
   715 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   716 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   717 INCOMPATIBILITY.
   718 
   719 * Theory Library/SetsAndFunctions has been split into
   720 Library/Function_Algebras and Library/Set_Algebras; canonical names
   721 for instance definitions for functions; various improvements.
   722 INCOMPATIBILITY.
   723 
   724 * Theory Library/Multiset provides stable quicksort implementation of
   725 sort_key.
   726 
   727 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   728 INCOMPATIBILITY.
   729 
   730 * Session Multivariate_Analysis: introduced a type class for euclidean
   731 space.  Most theorems are now stated in terms of euclidean spaces
   732 instead of finite cartesian products.
   733 
   734   types
   735     real ^ 'n ~>  'a::real_vector
   736               ~>  'a::euclidean_space
   737               ~>  'a::ordered_euclidean_space
   738         (depends on your needs)
   739 
   740   constants
   741      _ $ _        ~> _ $$ _
   742      \<chi> x. _  ~> \<chi>\<chi> x. _
   743      CARD('n)     ~> DIM('a)
   744 
   745 Also note that the indices are now natural numbers and not from some
   746 finite type. Finite cartesian products of euclidean spaces, products
   747 of euclidean spaces the real and complex numbers are instantiated to
   748 be euclidean_spaces.  INCOMPATIBILITY.
   749 
   750 * Session Probability: introduced pextreal as positive extended real
   751 numbers.  Use pextreal as value for measures.  Introduce the
   752 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   753 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   754 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   755 
   756 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   757 INCOMPATIBILITY.
   758 
   759 * Session SPARK (with image HOL-SPARK) provides commands to load and
   760 prove verification conditions generated by the SPARK Ada program
   761 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   762 
   763 
   764 *** HOL-Algebra ***
   765 
   766 * Theorems for additive ring operations (locale abelian_monoid and
   767 descendants) are generated by interpretation from their multiplicative
   768 counterparts.  Names (in particular theorem names) have the mandatory
   769 qualifier 'add'.  Previous theorem names are redeclared for
   770 compatibility.
   771 
   772 * Structure "int_ring" is now an abbreviation (previously a
   773 definition).  This fits more natural with advanced interpretations.
   774 
   775 
   776 *** HOLCF ***
   777 
   778 * The domain package now runs in definitional mode by default: The
   779 former command 'new_domain' is now called 'domain'.  To use the domain
   780 package in its original axiomatic mode, use 'domain (unsafe)'.
   781 INCOMPATIBILITY.
   782 
   783 * The new class "domain" is now the default sort.  Class "predomain"
   784 is an unpointed version of "domain". Theories can be updated by
   785 replacing sort annotations as shown below.  INCOMPATIBILITY.
   786 
   787   'a::type ~> 'a::countable
   788   'a::cpo  ~> 'a::predomain
   789   'a::pcpo ~> 'a::domain
   790 
   791 * The old type class "rep" has been superseded by class "domain".
   792 Accordingly, users of the definitional package must remove any
   793 "default_sort rep" declarations.  INCOMPATIBILITY.
   794 
   795 * The domain package (definitional mode) now supports unpointed
   796 predomain argument types, as long as they are marked 'lazy'. (Strict
   797 arguments must be in class "domain".) For example, the following
   798 domain definition now works:
   799 
   800   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   801 
   802 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   803 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   804 'a option, and 'a list.  Additionally, it configures fixrec and the
   805 domain package to work with these types.  For example:
   806 
   807   fixrec isInl :: "('a + 'b) u -> tr"
   808     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   809 
   810   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   811 
   812 * The "(permissive)" option of fixrec has been replaced with a
   813 per-equation "(unchecked)" option. See
   814 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
   815 
   816 * The "bifinite" class no longer fixes a constant "approx"; the class
   817 now just asserts that such a function exists.  INCOMPATIBILITY.
   818 
   819 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
   820 defines an embedding of type 'a defl into udom by default; instances
   821 of "bifinite" and "domain" classes are available in
   822 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
   823 
   824 * The syntax "REP('a)" has been replaced with "DEFL('a)".
   825 
   826 * The predicate "directed" has been removed.  INCOMPATIBILITY.
   827 
   828 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
   829 
   830 * The function "cprod_map" has been renamed to "prod_map".
   831 INCOMPATIBILITY.
   832 
   833 * The monadic bind operator on each powerdomain has new binder syntax
   834 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
   835 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
   836 
   837 * The infix syntax for binary union on each powerdomain has changed
   838 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
   839 syntax.  INCOMPATIBILITY.
   840 
   841 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
   842 still supported as an input translation.
   843 
   844 * Renamed some theorems (the original names are also still available).
   845 
   846   expand_fun_below   ~> fun_below_iff
   847   below_fun_ext      ~> fun_belowI
   848   expand_cfun_eq     ~> cfun_eq_iff
   849   ext_cfun           ~> cfun_eqI
   850   expand_cfun_below  ~> cfun_below_iff
   851   below_cfun_ext     ~> cfun_belowI
   852   cont2cont_Rep_CFun ~> cont2cont_APP
   853 
   854 * The Abs and Rep functions for various types have changed names.
   855 Related theorem names have also changed to match. INCOMPATIBILITY.
   856 
   857   Rep_CFun  ~> Rep_cfun
   858   Abs_CFun  ~> Abs_cfun
   859   Rep_Sprod ~> Rep_sprod
   860   Abs_Sprod ~> Abs_sprod
   861   Rep_Ssum  ~> Rep_ssum
   862   Abs_Ssum  ~> Abs_ssum
   863 
   864 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   865 been renamed to *_bottom_iff.  INCOMPATIBILITY.
   866 
   867 * Various changes to bisimulation/coinduction with domain package:
   868 
   869   - Definitions of "bisim" constants no longer mention definedness.
   870   - With mutual recursion, "bisim" predicate is now curried.
   871   - With mutual recursion, each type gets a separate coind theorem.
   872   - Variable names in bisim_def and coinduct rules have changed.
   873 
   874 INCOMPATIBILITY.
   875 
   876 * Case combinators generated by the domain package for type "foo" are
   877 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
   878 
   879 * Several theorems have been renamed to more accurately reflect the
   880 names of constants and types involved.  INCOMPATIBILITY.
   881 
   882   thelub_const    ~> lub_const
   883   lub_const       ~> is_lub_const
   884   thelubI         ~> lub_eqI
   885   is_lub_lub      ~> is_lubD2
   886   lubI            ~> is_lub_lub
   887   unique_lub      ~> is_lub_unique
   888   is_ub_lub       ~> is_lub_rangeD1
   889   lub_bin_chain   ~> is_lub_bin_chain
   890   lub_fun         ~> is_lub_fun
   891   thelub_fun      ~> lub_fun
   892   thelub_cfun     ~> lub_cfun
   893   thelub_Pair     ~> lub_Pair
   894   lub_cprod       ~> is_lub_prod
   895   thelub_cprod    ~> lub_prod
   896   minimal_cprod   ~> minimal_prod
   897   inst_cprod_pcpo ~> inst_prod_pcpo
   898   UU_I            ~> bottomI
   899   compact_UU      ~> compact_bottom
   900   deflation_UU    ~> deflation_bottom
   901   finite_deflation_UU ~> finite_deflation_bottom
   902 
   903 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
   904 
   905   sq_ord_less_eq_trans ~> below_eq_trans
   906   sq_ord_eq_less_trans ~> eq_below_trans
   907   refl_less            ~> below_refl
   908   trans_less           ~> below_trans
   909   antisym_less         ~> below_antisym
   910   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
   911   box_less             ~> box_below
   912   rev_trans_less       ~> rev_below_trans
   913   not_less2not_eq      ~> not_below2not_eq
   914   less_UU_iff          ~> below_UU_iff
   915   flat_less_iff        ~> flat_below_iff
   916   adm_less             ~> adm_below
   917   adm_not_less         ~> adm_not_below
   918   adm_compact_not_less ~> adm_compact_not_below
   919   less_fun_def         ~> below_fun_def
   920   expand_fun_less      ~> fun_below_iff
   921   less_fun_ext         ~> fun_belowI
   922   less_discr_def       ~> below_discr_def
   923   discr_less_eq        ~> discr_below_eq
   924   less_unit_def        ~> below_unit_def
   925   less_cprod_def       ~> below_prod_def
   926   prod_lessI           ~> prod_belowI
   927   Pair_less_iff        ~> Pair_below_iff
   928   fst_less_iff         ~> fst_below_iff
   929   snd_less_iff         ~> snd_below_iff
   930   expand_cfun_less     ~> cfun_below_iff
   931   less_cfun_ext        ~> cfun_belowI
   932   injection_less       ~> injection_below
   933   less_up_def          ~> below_up_def
   934   not_Iup_less         ~> not_Iup_below
   935   Iup_less             ~> Iup_below
   936   up_less              ~> up_below
   937   Def_inject_less_eq   ~> Def_below_Def
   938   Def_less_is_eq       ~> Def_below_iff
   939   spair_less_iff       ~> spair_below_iff
   940   less_sprod           ~> below_sprod
   941   spair_less           ~> spair_below
   942   sfst_less_iff        ~> sfst_below_iff
   943   ssnd_less_iff        ~> ssnd_below_iff
   944   fix_least_less       ~> fix_least_below
   945   dist_less_one        ~> dist_below_one
   946   less_ONE             ~> below_ONE
   947   ONE_less_iff         ~> ONE_below_iff
   948   less_sinlD           ~> below_sinlD
   949   less_sinrD           ~> below_sinrD
   950 
   951 
   952 *** FOL and ZF ***
   953 
   954 * All constant names are now qualified internally and use proper
   955 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
   956 
   957 
   958 *** ML ***
   959 
   960 * Antiquotation @{assert} inlines a function bool -> unit that raises
   961 Fail if the argument is false.  Due to inlining the source position of
   962 failed assertions is included in the error output.
   963 
   964 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
   965 text is in practice always evaluated with a stable theory checkpoint.
   966 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
   967 
   968 * Antiquotation @{theory A} refers to theory A from the ancestry of
   969 the current context, not any accidental theory loader state as before.
   970 Potential INCOMPATIBILITY, subtle change in semantics.
   971 
   972 * Syntax.pretty_priority (default 0) configures the required priority
   973 of pretty-printed output and thus affects insertion of parentheses.
   974 
   975 * Syntax.default_root (default "any") configures the inner syntax
   976 category (nonterminal symbol) for parsing of terms.
   977 
   978 * Former exception Library.UnequalLengths now coincides with
   979 ListPair.UnequalLengths.
   980 
   981 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
   982 main functionality is provided by structure Simplifier.
   983 
   984 * Renamed raw "explode" function to "raw_explode" to emphasize its
   985 meaning.  Note that internally to Isabelle, Symbol.explode is used in
   986 almost all situations.
   987 
   988 * Discontinued obsolete function sys_error and exception SYS_ERROR.
   989 See implementation manual for further details on exceptions in
   990 Isabelle/ML.
   991 
   992 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   993 meaning.
   994 
   995 * Renamed structure PureThy to Pure_Thy and moved most of its
   996 operations to structure Global_Theory, to emphasize that this is
   997 rarely-used global-only stuff.
   998 
   999 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
  1000 instead (or tracing for high-volume output).
  1001 
  1002 * Configuration option show_question_marks only affects regular pretty
  1003 printing of types and terms, not raw Term.string_of_vname.
  1004 
  1005 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
  1006 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
  1007 @{thms} for most purposes.
  1008 
  1009 * ML structure Unsynchronized is never opened, not even in Isar
  1010 interaction mode as before.  Old Unsynchronized.set etc. have been
  1011 discontinued -- use plain := instead.  This should be *rare* anyway,
  1012 since modern tools always work via official context data, notably
  1013 configuration options.
  1014 
  1015 * Parallel and asynchronous execution requires special care concerning
  1016 interrupts.  Structure Exn provides some convenience functions that
  1017 avoid working directly with raw Interrupt.  User code must not absorb
  1018 interrupts -- intermediate handling (for cleanup etc.) needs to be
  1019 followed by re-raising of the original exception.  Another common
  1020 source of mistakes are "handle _" patterns, which make the meaning of
  1021 the program subject to physical effects of the environment.
  1022 
  1023 
  1024 
  1025 New in Isabelle2009-2 (June 2010)
  1026 ---------------------------------
  1027 
  1028 *** General ***
  1029 
  1030 * Authentic syntax for *all* logical entities (type classes, type
  1031 constructors, term constants): provides simple and robust
  1032 correspondence between formal entities and concrete syntax.  Within
  1033 the parse tree / AST representations, "constants" are decorated by
  1034 their category (class, type, const) and spelled out explicitly with
  1035 their full internal name.
  1036 
  1037 Substantial INCOMPATIBILITY concerning low-level syntax declarations
  1038 and translations (translation rules and translation functions in ML).
  1039 Some hints on upgrading:
  1040 
  1041   - Many existing uses of 'syntax' and 'translations' can be replaced
  1042     by more modern 'type_notation', 'notation' and 'abbreviation',
  1043     which are independent of this issue.
  1044 
  1045   - 'translations' require markup within the AST; the term syntax
  1046     provides the following special forms:
  1047 
  1048       CONST c   -- produces syntax version of constant c from context
  1049       XCONST c  -- literally c, checked as constant from context
  1050       c         -- literally c, if declared by 'syntax'
  1051 
  1052     Plain identifiers are treated as AST variables -- occasionally the
  1053     system indicates accidental variables via the error "rhs contains
  1054     extra variables".
  1055 
  1056     Type classes and type constructors are marked according to their
  1057     concrete syntax.  Some old translations rules need to be written
  1058     for the "type" category, using type constructor application
  1059     instead of pseudo-term application of the default category
  1060     "logic".
  1061 
  1062   - 'parse_translation' etc. in ML may use the following
  1063     antiquotations:
  1064 
  1065       @{class_syntax c}   -- type class c within parse tree / AST
  1066       @{term_syntax c}    -- type constructor c within parse tree / AST
  1067       @{const_syntax c}   -- ML version of "CONST c" above
  1068       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
  1069 
  1070   - Literal types within 'typed_print_translations', i.e. those *not*
  1071     represented as pseudo-terms are represented verbatim.  Use @{class
  1072     c} or @{type_name c} here instead of the above syntax
  1073     antiquotations.
  1074 
  1075 Note that old non-authentic syntax was based on unqualified base
  1076 names, so all of the above "constant" names would coincide.  Recall
  1077 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
  1078 diagnose syntax problems.
  1079 
  1080 * Type constructors admit general mixfix syntax, not just infix.
  1081 
  1082 * Concrete syntax may be attached to local entities without a proof
  1083 body, too.  This works via regular mixfix annotations for 'fix',
  1084 'def', 'obtain' etc. or via the explicit 'write' command, which is
  1085 similar to the 'notation' command in theory specifications.
  1086 
  1087 * Discontinued unnamed infix syntax (legacy feature for many years) --
  1088 need to specify constant name and syntax separately.  Internal ML
  1089 datatype constructors have been renamed from InfixName to Infix etc.
  1090 Minor INCOMPATIBILITY.
  1091 
  1092 * Schematic theorem statements need to be explicitly markup as such,
  1093 via commands 'schematic_lemma', 'schematic_theorem',
  1094 'schematic_corollary'.  Thus the relevance of the proof is made
  1095 syntactically clear, which impacts performance in a parallel or
  1096 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  1097 
  1098 * Use of cumulative prems via "!" in some proof methods has been
  1099 discontinued (old legacy feature).
  1100 
  1101 * References 'trace_simp' and 'debug_simp' have been replaced by
  1102 configuration options stored in the context. Enabling tracing (the
  1103 case of debugging is similar) in proofs works via
  1104 
  1105   using [[trace_simp = true]]
  1106 
  1107 Tracing is then active for all invocations of the simplifier in
  1108 subsequent goal refinement steps. Tracing may also still be enabled or
  1109 disabled via the ProofGeneral settings menu.
  1110 
  1111 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  1112 'hide_fact' replace the former 'hide' KIND command.  Minor
  1113 INCOMPATIBILITY.
  1114 
  1115 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  1116 more efficient than combinations with -q1 or -q2.
  1117 
  1118 
  1119 *** Pure ***
  1120 
  1121 * Proofterms record type-class reasoning explicitly, using the
  1122 "unconstrain" operation internally.  This eliminates all sort
  1123 constraints from a theorem and proof, introducing explicit
  1124 OFCLASS-premises.  On the proof term level, this operation is
  1125 automatically applied at theorem boundaries, such that closed proofs
  1126 are always free of sort constraints.  INCOMPATIBILITY for tools that
  1127 inspect proof terms.
  1128 
  1129 * Local theory specifications may depend on extra type variables that
  1130 are not present in the result type -- arguments TYPE('a) :: 'a itself
  1131 are added internally.  For example:
  1132 
  1133   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  1134 
  1135 * Predicates of locales introduced by classes carry a mandatory
  1136 "class" prefix.  INCOMPATIBILITY.
  1137 
  1138 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  1139 
  1140 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  1141 'class' instead.
  1142 
  1143 * Command 'code_reflect' allows to incorporate generated ML code into
  1144 runtime environment; replaces immature code_datatype antiquotation.
  1145 INCOMPATIBILITY.
  1146 
  1147 * Code generator: simple concept for abstract datatypes obeying
  1148 invariants.
  1149 
  1150 * Code generator: details of internal data cache have no impact on the
  1151 user space functionality any longer.
  1152 
  1153 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1154 subgoals.  This is more appropriate for interpretations with 'where'.
  1155 INCOMPATIBILITY.
  1156 
  1157 * Command 'example_proof' opens an empty proof body.  This allows to
  1158 experiment with Isar, without producing any persistent result.
  1159 
  1160 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1161 within a local theory context, with explicit checking of the
  1162 constructors involved (in contrast to the raw 'syntax' versions).
  1163 
  1164 * Commands 'types' and 'typedecl' now work within a local theory
  1165 context -- without introducing dependencies on parameters or
  1166 assumptions, which is not possible in Isabelle/Pure.
  1167 
  1168 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1169 within a local theory context.  Minor INCOMPATIBILITY.
  1170 
  1171 
  1172 *** HOL ***
  1173 
  1174 * Command 'typedef' now works within a local theory context -- without
  1175 introducing dependencies on parameters or assumptions, which is not
  1176 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1177 contain multiple interpretations of local typedefs (with different
  1178 non-emptiness proofs), even in a global theory context.
  1179 
  1180 * New package for quotient types.  Commands 'quotient_type' and
  1181 'quotient_definition' may be used for defining types and constants by
  1182 quotient constructions.  An example is the type of integers created by
  1183 quotienting pairs of natural numbers:
  1184 
  1185   fun
  1186     intrel :: "(nat * nat) => (nat * nat) => bool"
  1187   where
  1188     "intrel (x, y) (u, v) = (x + v = u + y)"
  1189 
  1190   quotient_type int = "nat * nat" / intrel
  1191     by (auto simp add: equivp_def expand_fun_eq)
  1192 
  1193   quotient_definition
  1194     "0::int" is "(0::nat, 0::nat)"
  1195 
  1196 The method "lifting" can be used to lift of theorems from the
  1197 underlying "raw" type to the quotient type.  The example
  1198 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1199 construction and provides a reasoning infrastructure for finite sets.
  1200 
  1201 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1202 clash with new theory Quotient in Main HOL.
  1203 
  1204 * Moved the SMT binding into the main HOL session, eliminating
  1205 separate HOL-SMT session.
  1206 
  1207 * List membership infix mem operation is only an input abbreviation.
  1208 INCOMPATIBILITY.
  1209 
  1210 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1211 for future developements; former Library/Word.thy is still present in
  1212 the AFP entry RSAPPS.
  1213 
  1214 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1215 longer shadowed.  INCOMPATIBILITY.
  1216 
  1217 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1218 INCOMPATIBILITY.
  1219 
  1220 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1221 INCOMPATIBILITY.
  1222 
  1223 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1224 instead.  INCOMPATIBILITY.
  1225 
  1226 * Dropped several real-specific versions of lemmas about floor and
  1227 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1228 instead.  INCOMPATIBILITY.
  1229 
  1230   floor_number_of_eq         ~> floor_number_of
  1231   le_floor_eq_number_of      ~> number_of_le_floor
  1232   le_floor_eq_zero           ~> zero_le_floor
  1233   le_floor_eq_one            ~> one_le_floor
  1234   floor_less_eq_number_of    ~> floor_less_number_of
  1235   floor_less_eq_zero         ~> floor_less_zero
  1236   floor_less_eq_one          ~> floor_less_one
  1237   less_floor_eq_number_of    ~> number_of_less_floor
  1238   less_floor_eq_zero         ~> zero_less_floor
  1239   less_floor_eq_one          ~> one_less_floor
  1240   floor_le_eq_number_of      ~> floor_le_number_of
  1241   floor_le_eq_zero           ~> floor_le_zero
  1242   floor_le_eq_one            ~> floor_le_one
  1243   floor_subtract_number_of   ~> floor_diff_number_of
  1244   floor_subtract_one         ~> floor_diff_one
  1245   ceiling_number_of_eq       ~> ceiling_number_of
  1246   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1247   ceiling_le_zero_eq         ~> ceiling_le_zero
  1248   ceiling_le_eq_one          ~> ceiling_le_one
  1249   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1250   less_ceiling_eq_zero       ~> zero_less_ceiling
  1251   less_ceiling_eq_one        ~> one_less_ceiling
  1252   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1253   ceiling_less_eq_zero       ~> ceiling_less_zero
  1254   ceiling_less_eq_one        ~> ceiling_less_one
  1255   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1256   le_ceiling_eq_zero         ~> zero_le_ceiling
  1257   le_ceiling_eq_one          ~> one_le_ceiling
  1258   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1259   ceiling_subtract_one       ~> ceiling_diff_one
  1260 
  1261 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1262 application of the various fold combinators on finite sets.
  1263 
  1264 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1265 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1266 implementation.  INCOMPATIBILTY.
  1267 
  1268 * Theory Library/Coinductive_List has been removed -- superseded by
  1269 AFP/thys/Coinductive.
  1270 
  1271 * Theory PReal, including the type "preal" and related operations, has
  1272 been removed.  INCOMPATIBILITY.
  1273 
  1274 * Real: new development using Cauchy Sequences.
  1275 
  1276 * Split off theory "Big_Operators" containing setsum, setprod,
  1277 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1278 
  1279 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1280 "Int" etc.  INCOMPATIBILITY.
  1281 
  1282 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1283 
  1284 * New set of rules "ac_simps" provides combined assoc / commute
  1285 rewrites for all interpretations of the appropriate generic locales.
  1286 
  1287 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1288 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1289 appropriate and more consistent names suitable for name prefixes
  1290 within the HOL theories.  INCOMPATIBILITY.
  1291 
  1292 * Some generic constants have been put to appropriate theories:
  1293   - less_eq, less: Orderings
  1294   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1295   - inverse, divide: Rings
  1296 INCOMPATIBILITY.
  1297 
  1298 * More consistent naming of type classes involving orderings (and
  1299 lattices):
  1300 
  1301     lower_semilattice                   ~> semilattice_inf
  1302     upper_semilattice                   ~> semilattice_sup
  1303 
  1304     dense_linear_order                  ~> dense_linorder
  1305 
  1306     pordered_ab_group_add               ~> ordered_ab_group_add
  1307     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1308     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1309     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1310     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1311     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1312     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1313     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1314     pordered_comm_ring                  ~> ordered_comm_ring
  1315     pordered_comm_semiring              ~> ordered_comm_semiring
  1316     pordered_ring                       ~> ordered_ring
  1317     pordered_ring_abs                   ~> ordered_ring_abs
  1318     pordered_semiring                   ~> ordered_semiring
  1319 
  1320     ordered_ab_group_add                ~> linordered_ab_group_add
  1321     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1322     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1323     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1324     ordered_field                       ~> linordered_field
  1325     ordered_field_no_lb                 ~> linordered_field_no_lb
  1326     ordered_field_no_ub                 ~> linordered_field_no_ub
  1327     ordered_field_dense_linear_order    ~> dense_linordered_field
  1328     ordered_idom                        ~> linordered_idom
  1329     ordered_ring                        ~> linordered_ring
  1330     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1331     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1332     ordered_ring_strict                 ~> linordered_ring_strict
  1333     ordered_semidom                     ~> linordered_semidom
  1334     ordered_semiring                    ~> linordered_semiring
  1335     ordered_semiring_1                  ~> linordered_semiring_1
  1336     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1337     ordered_semiring_strict             ~> linordered_semiring_strict
  1338 
  1339   The following slightly odd type classes have been moved to a
  1340   separate theory Library/Lattice_Algebras:
  1341 
  1342     lordered_ab_group_add               ~> lattice_ab_group_add
  1343     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1344     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1345     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1346     lordered_ring                       ~> lattice_ring
  1347 
  1348 INCOMPATIBILITY.
  1349 
  1350 * Refined field classes:
  1351   - classes division_ring_inverse_zero, field_inverse_zero,
  1352     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1353     subsumes former division_by_zero class;
  1354   - numerous lemmas have been ported from field to division_ring.
  1355 INCOMPATIBILITY.
  1356 
  1357 * Refined algebra theorem collections:
  1358   - dropped theorem group group_simps, use algebra_simps instead;
  1359   - dropped theorem group ring_simps, use field_simps instead;
  1360   - proper theorem collection field_simps subsumes former theorem
  1361     groups field_eq_simps and field_simps;
  1362   - dropped lemma eq_minus_self_iff which is a duplicate for
  1363     equal_neg_zero.
  1364 INCOMPATIBILITY.
  1365 
  1366 * Theory Finite_Set and List: some lemmas have been generalized from
  1367 sets to lattices:
  1368 
  1369   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1370   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1371   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1372   union_Union_fold_union        ~> sup_Sup_fold_sup
  1373   Inter_fold_inter              ~> Inf_fold_inf
  1374   Union_fold_union              ~> Sup_fold_sup
  1375   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1376   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1377   INTER_fold_inter              ~> INFI_fold_inf
  1378   UNION_fold_union              ~> SUPR_fold_sup
  1379 
  1380 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1381 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1382 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1383 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1384 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1385 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1386 
  1387 * Reorganized theory Multiset: swapped notation of pointwise and
  1388 multiset order:
  1389 
  1390   - pointwise ordering is instance of class order with standard syntax
  1391     <= and <;
  1392   - multiset ordering has syntax <=# and <#; partial order properties
  1393     are provided by means of interpretation with prefix
  1394     multiset_order;
  1395   - less duplication, less historical organization of sections,
  1396     conversion from associations lists to multisets, rudimentary code
  1397     generation;
  1398   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1399     if needed.
  1400 
  1401 Renamed:
  1402 
  1403   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1404   multi_count_ext  ~>  multiset_ext
  1405   diff_union_inverse2  ~>  diff_union_cancelR
  1406 
  1407 INCOMPATIBILITY.
  1408 
  1409 * Theory Permutation: replaced local "remove" by List.remove1.
  1410 
  1411 * Code generation: ML and OCaml code is decorated with signatures.
  1412 
  1413 * Theory List: added transpose.
  1414 
  1415 * Library/Nat_Bijection.thy is a collection of bijective functions
  1416 between nat and other types, which supersedes the older libraries
  1417 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1418 
  1419   Constants:
  1420   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1421   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1422   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1423   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1424   Countable.pair_encode           ~> prod_encode
  1425   NatIso.prod2nat                 ~> prod_encode
  1426   NatIso.nat2prod                 ~> prod_decode
  1427   NatIso.sum2nat                  ~> sum_encode
  1428   NatIso.nat2sum                  ~> sum_decode
  1429   NatIso.list2nat                 ~> list_encode
  1430   NatIso.nat2list                 ~> list_decode
  1431   NatIso.set2nat                  ~> set_encode
  1432   NatIso.nat2set                  ~> set_decode
  1433 
  1434   Lemmas:
  1435   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1436   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1437   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1438   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1439   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1440   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1441   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1442   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1443   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1444   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1445   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1446   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1447   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1448 
  1449 * Sledgehammer:
  1450   - Renamed ATP commands:
  1451     atp_info     ~> sledgehammer running_atps
  1452     atp_kill     ~> sledgehammer kill_atps
  1453     atp_messages ~> sledgehammer messages
  1454     atp_minimize ~> sledgehammer minimize
  1455     print_atps   ~> sledgehammer available_atps
  1456     INCOMPATIBILITY.
  1457   - Added user's manual ("isabelle doc sledgehammer").
  1458   - Added option syntax and "sledgehammer_params" to customize
  1459     Sledgehammer's behavior.  See the manual for details.
  1460   - Modified the Isar proof reconstruction code so that it produces
  1461     direct proofs rather than proofs by contradiction.  (This feature
  1462     is still experimental.)
  1463   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1464     full-typed mode.
  1465   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1466 
  1467 * Nitpick:
  1468   - Added and implemented "binary_ints" and "bits" options.
  1469   - Added "std" option and implemented support for nonstandard models.
  1470   - Added and implemented "finitize" option to improve the precision
  1471     of infinite datatypes based on a monotonicity analysis.
  1472   - Added support for quotient types.
  1473   - Added support for "specification" and "ax_specification"
  1474     constructs.
  1475   - Added support for local definitions (for "function" and
  1476     "termination" proofs).
  1477   - Added support for term postprocessors.
  1478   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1479   - Improved efficiency of "destroy_constrs" optimization.
  1480   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1481     record getters.
  1482   - Fixed soundness bug related to higher-order constructors.
  1483   - Fixed soundness bug when "full_descrs" is enabled.
  1484   - Improved precision of set constructs.
  1485   - Added "atoms" option.
  1486   - Added cache to speed up repeated Kodkod invocations on the same
  1487     problems.
  1488   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1489     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1490     "SAT4J_Light".  INCOMPATIBILITY.
  1491   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1492     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1493   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1494 
  1495 * Method "induct" now takes instantiations of the form t, where t is not
  1496   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1497   If this is not intended, t has to be enclosed in parentheses.
  1498   By default, the equalities generated by definitional instantiations
  1499   are pre-simplified, which may cause parameters of inductive cases
  1500   to disappear, or may even delete some of the inductive cases.
  1501   Use "induct (no_simp)" instead of "induct" to restore the old
  1502   behaviour. The (no_simp) option is also understood by the "cases"
  1503   and "nominal_induct" methods, which now perform pre-simplification, too.
  1504   INCOMPATIBILITY.
  1505 
  1506 
  1507 *** HOLCF ***
  1508 
  1509 * Variable names in lemmas generated by the domain package have
  1510 changed; the naming scheme is now consistent with the HOL datatype
  1511 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1512 
  1513 * The domain package no longer defines the function "foo_copy" for
  1514 recursive domain "foo".  The reach lemma is now stated directly in
  1515 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1516 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1517 
  1518 * Most definedness lemmas generated by the domain package (previously
  1519 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1520 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1521 Proofs that used definedness lemmas as intro rules may break,
  1522 potential INCOMPATIBILITY.
  1523 
  1524 * Induction and casedist rules generated by the domain package now
  1525 declare proper case_names (one called "bottom", and one named for each
  1526 constructor).  INCOMPATIBILITY.
  1527 
  1528 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1529 rules are generated for each domain, INCOMPATIBILITY.
  1530 
  1531   foo_bar.reach       ~> foo.reach  bar.reach
  1532   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1533 
  1534 * Some lemmas generated by the domain package have been renamed for
  1535 consistency with the datatype package, INCOMPATIBILITY.
  1536 
  1537   foo.ind        ~> foo.induct
  1538   foo.finite_ind ~> foo.finite_induct
  1539   foo.coind      ~> foo.coinduct
  1540   foo.casedist   ~> foo.exhaust
  1541   foo.exhaust    ~> foo.nchotomy
  1542 
  1543 * For consistency with other definition packages, the fixrec package
  1544 now generates qualified theorem names, INCOMPATIBILITY.
  1545 
  1546   foo_simps  ~> foo.simps
  1547   foo_unfold ~> foo.unfold
  1548   foo_induct ~> foo.induct
  1549 
  1550 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1551 method and internal fixrec proofs now use the default simpset instead.
  1552 INCOMPATIBILITY.
  1553 
  1554 * The "contlub" predicate has been removed.  Proof scripts should use
  1555 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1556 
  1557 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1558 
  1559 * The constants cpair, cfst, and csnd have been removed in favor of
  1560 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1561 
  1562 
  1563 *** ML ***
  1564 
  1565 * Antiquotations for basic formal entities:
  1566 
  1567     @{class NAME}         -- type class
  1568     @{class_syntax NAME}  -- syntax representation of the above
  1569 
  1570     @{type_name NAME}     -- logical type
  1571     @{type_abbrev NAME}   -- type abbreviation
  1572     @{nonterminal NAME}   -- type of concrete syntactic category
  1573     @{type_syntax NAME}   -- syntax representation of any of the above
  1574 
  1575     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1576     @{const_abbrev NAME}  -- abbreviated constant
  1577     @{const_syntax NAME}  -- syntax representation of any of the above
  1578 
  1579 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1580 syntax constant (cf. 'syntax' command).
  1581 
  1582 * Antiquotation @{make_string} inlines a function to print arbitrary
  1583 values similar to the ML toplevel.  The result is compiler dependent
  1584 and may fall back on "?" in certain situations.
  1585 
  1586 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1587 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1588 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1589 not work with the asynchronous Isar document model.
  1590 
  1591 * Configuration options now admit dynamic default values, depending on
  1592 the context or even global references.
  1593 
  1594 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1595 uses an efficient external library if available (for Poly/ML).
  1596 
  1597 * Renamed some important ML structures, while keeping the old names
  1598 for some time as aliases within the structure Legacy:
  1599 
  1600   OuterKeyword  ~>  Keyword
  1601   OuterLex      ~>  Token
  1602   OuterParse    ~>  Parse
  1603   OuterSyntax   ~>  Outer_Syntax
  1604   PrintMode     ~>  Print_Mode
  1605   SpecParse     ~>  Parse_Spec
  1606   ThyInfo       ~>  Thy_Info
  1607   ThyLoad       ~>  Thy_Load
  1608   ThyOutput     ~>  Thy_Output
  1609   TypeInfer     ~>  Type_Infer
  1610 
  1611 Note that "open Legacy" simplifies porting of sources, but forgetting
  1612 to remove it again will complicate porting again in the future.
  1613 
  1614 * Most operations that refer to a global context are named
  1615 accordingly, e.g. Simplifier.global_context or
  1616 ProofContext.init_global.  There are some situations where a global
  1617 context actually works, but under normal circumstances one needs to
  1618 pass the proper local context through the code!
  1619 
  1620 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1621 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1622 Pretty.pp argument to merge, which is absent in the standard
  1623 Theory_Data version.
  1624 
  1625 * Sorts.certify_sort and derived "cert" operations for types and terms
  1626 no longer minimize sorts.  Thus certification at the boundary of the
  1627 inference kernel becomes invariant under addition of class relations,
  1628 which is an important monotonicity principle.  Sorts are now minimized
  1629 in the syntax layer only, at the boundary between the end-user and the
  1630 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1631 explicitly in rare situations.
  1632 
  1633 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1634 emphasize that this is in no way a standard operation.
  1635 INCOMPATIBILITY.
  1636 
  1637 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1638 usual for resolution.  Rare INCOMPATIBILITY.
  1639 
  1640 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1641 to emphasize that these only work in a global situation (which is
  1642 quite rare).
  1643 
  1644 * Curried take and drop in library.ML; negative length is interpreted
  1645 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1646 
  1647 * Proof terms: type substitutions on proof constants now use canonical
  1648 order of type variables.  INCOMPATIBILITY for tools working with proof
  1649 terms.
  1650 
  1651 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1652 may no longer carry premises.  User-level specifications are
  1653 transformed accordingly by Thm.add_axiom/add_def.
  1654 
  1655 
  1656 *** System ***
  1657 
  1658 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1659 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1660 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1661 
  1662 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1663 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1664 respectively.
  1665 
  1666 * Old lib/scripts/polyml-platform is superseded by the
  1667 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1668 variant, even on a 64 bit machine.  The following example setting
  1669 prefers 64 bit if available:
  1670 
  1671   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1672 
  1673 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1674 Isabelle/Scala layer for advanced prover interaction and integration.
  1675 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1676 component.
  1677 
  1678 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1679 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1680 similar to the default assignment of the document preparation system
  1681 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1682 provides some operations for direct access to the font without asking
  1683 the user for manual installation.
  1684 
  1685 
  1686 
  1687 New in Isabelle2009-1 (December 2009)
  1688 -------------------------------------
  1689 
  1690 *** General ***
  1691 
  1692 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1693 one backslash should be used, even in ML sources.
  1694 
  1695 
  1696 *** Pure ***
  1697 
  1698 * Locale interpretation propagates mixins along the locale hierarchy.
  1699 The currently only available mixins are the equations used to map
  1700 local definitions to terms of the target domain of an interpretation.
  1701 
  1702 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1703 loc" to print all interpretations of locale "loc" in the theory.
  1704 Interpretations in proofs are not shown.
  1705 
  1706 * Thoroughly revised locales tutorial.  New section on conditional
  1707 interpretation.
  1708 
  1709 * On instantiation of classes, remaining undefined class parameters
  1710 are formally declared.  INCOMPATIBILITY.
  1711 
  1712 
  1713 *** Document preparation ***
  1714 
  1715 * New generalized style concept for printing terms: @{foo (style) ...}
  1716 instead of @{foo_style style ...}  (old form is still retained for
  1717 backward compatibility).  Styles can be also applied for
  1718 antiquotations prop, term_type and typeof.
  1719 
  1720 
  1721 *** HOL ***
  1722 
  1723 * New proof method "smt" for a combination of first-order logic with
  1724 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1725 fixed-size bitvectors; there is also basic support for higher-order
  1726 features (esp. lambda abstractions).  It is an incomplete decision
  1727 procedure based on external SMT solvers using the oracle mechanism;
  1728 for the SMT solver Z3, this method is proof-producing.  Certificates
  1729 are provided to avoid calling the external solvers solely for
  1730 re-checking proofs.  Due to a remote SMT service there is no need for
  1731 installing SMT solvers locally.  See src/HOL/SMT.
  1732 
  1733 * New commands to load and prove verification conditions generated by
  1734 the Boogie program verifier or derived systems (e.g. the Verifying C
  1735 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1736 
  1737 * New counterexample generator tool 'nitpick' based on the Kodkod
  1738 relational model finder.  See src/HOL/Tools/Nitpick and
  1739 src/HOL/Nitpick_Examples.
  1740 
  1741 * New commands 'code_pred' and 'values' to invoke the predicate
  1742 compiler and to enumerate values of inductive predicates.
  1743 
  1744 * A tabled implementation of the reflexive transitive closure.
  1745 
  1746 * New implementation of quickcheck uses generic code generator;
  1747 default generators are provided for all suitable HOL types, records
  1748 and datatypes.  Old quickcheck can be re-activated importing theory
  1749 Library/SML_Quickcheck.
  1750 
  1751 * New testing tool Mirabelle for automated proof tools.  Applies
  1752 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1753 every proof step in a theory.  To be used in batch mode via the
  1754 "mirabelle" utility.
  1755 
  1756 * New proof method "sos" (sum of squares) for nonlinear real
  1757 arithmetic (originally due to John Harison). It requires theory
  1758 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1759 works well in practice on quantifier-free real arithmetic with +, -,
  1760 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1761 inequalities between polynomials.  It makes use of external
  1762 semidefinite programming solvers.  Method "sos" generates a
  1763 certificate that can be pasted into the proof thus avoiding the need
  1764 to call an external tool every time the proof is checked.  See
  1765 src/HOL/Library/Sum_Of_Squares.
  1766 
  1767 * New method "linarith" invokes existing linear arithmetic decision
  1768 procedure only.
  1769 
  1770 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1771 
  1772 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1773 Causes full type information to be output to the ATPs.  This slows
  1774 ATPs down considerably but eliminates a source of unsound "proofs"
  1775 that fail later.
  1776 
  1777 * New method "metisFT": A version of metis that uses full type
  1778 information in order to avoid failures of proof reconstruction.
  1779 
  1780 * New evaluator "approximate" approximates an real valued term using
  1781 the same method as the approximation method.
  1782 
  1783 * Method "approximate" now supports arithmetic expressions as
  1784 boundaries of intervals and implements interval splitting and Taylor
  1785 series expansion.
  1786 
  1787 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1788 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1789 
  1790 * New theory SupInf of the supremum and infimum operators for sets of
  1791 reals.
  1792 
  1793 * New theory Probability, which contains a development of measure
  1794 theory, eventually leading to Lebesgue integration and probability.
  1795 
  1796 * Extended Multivariate Analysis to include derivation and Brouwer's
  1797 fixpoint theorem.
  1798 
  1799 * Reorganization of number theory, INCOMPATIBILITY:
  1800   - new number theory development for nat and int, in theories Divides
  1801     and GCD as well as in new session Number_Theory
  1802   - some constants and facts now suffixed with _nat and _int
  1803     accordingly
  1804   - former session NumberTheory now named Old_Number_Theory, including
  1805     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1806   - moved theory Pocklington from src/HOL/Library to
  1807     src/HOL/Old_Number_Theory
  1808 
  1809 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1810 lcm of finite and infinite sets. It is shown that they form a complete
  1811 lattice.
  1812 
  1813 * Class semiring_div requires superclass no_zero_divisors and proof of
  1814 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1815 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1816 generalized to class semiring_div, subsuming former theorems
  1817 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1818 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1819 INCOMPATIBILITY.
  1820 
  1821 * Refinements to lattice classes and sets:
  1822   - less default intro/elim rules in locale variant, more default
  1823     intro/elim rules in class variant: more uniformity
  1824   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1825     le_inf_iff
  1826   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1827     sup_aci)
  1828   - renamed ACI to inf_sup_aci
  1829   - new class "boolean_algebra"
  1830   - class "complete_lattice" moved to separate theory
  1831     "Complete_Lattice"; corresponding constants (and abbreviations)
  1832     renamed and with authentic syntax:
  1833     Set.Inf ~>    Complete_Lattice.Inf
  1834     Set.Sup ~>    Complete_Lattice.Sup
  1835     Set.INFI ~>   Complete_Lattice.INFI
  1836     Set.SUPR ~>   Complete_Lattice.SUPR
  1837     Set.Inter ~>  Complete_Lattice.Inter
  1838     Set.Union ~>  Complete_Lattice.Union
  1839     Set.INTER ~>  Complete_Lattice.INTER
  1840     Set.UNION ~>  Complete_Lattice.UNION
  1841   - authentic syntax for
  1842     Set.Pow
  1843     Set.image
  1844   - mere abbreviations:
  1845     Set.empty               (for bot)
  1846     Set.UNIV                (for top)
  1847     Set.inter               (for inf, formerly Set.Int)
  1848     Set.union               (for sup, formerly Set.Un)
  1849     Complete_Lattice.Inter  (for Inf)
  1850     Complete_Lattice.Union  (for Sup)
  1851     Complete_Lattice.INTER  (for INFI)
  1852     Complete_Lattice.UNION  (for SUPR)
  1853   - object-logic definitions as far as appropriate
  1854 
  1855 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1856 Un_subset_iff are explicitly deleted as default simp rules; then also
  1857 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1858 deleted to achieve the desired effect.
  1859 
  1860 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1861 rules by default any longer; the same applies to min_max.inf_absorb1
  1862 etc.  INCOMPATIBILITY.
  1863 
  1864 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1865 pred_set_conv by default.  INCOMPATIBILITY.
  1866 
  1867 * Power operations on relations and functions are now one dedicated
  1868 constant "compow" with infix syntax "^^".  Power operation on
  1869 multiplicative monoids retains syntax "^" and is now defined generic
  1870 in class power.  INCOMPATIBILITY.
  1871 
  1872 * Relation composition "R O S" now has a more standard argument order:
  1873 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1874 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1875 break, since the O_assoc rule was not rewritten like this.  Fix using
  1876 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1877 
  1878 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1879 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1880 INCOMPATIBILITY.
  1881 
  1882 * Most rules produced by inductive and datatype package have mandatory
  1883 prefixes.  INCOMPATIBILITY.
  1884 
  1885 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1886 the attribute of the same name.  Each of the theorems in the list
  1887 DERIV_intros assumes composition with an additional function and
  1888 matches a variable to the derivative, which has to be solved by the
  1889 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1890 of most elementary terms.  Former Maclauren.DERIV_tac and
  1891 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1892 INCOMPATIBILITY.
  1893 
  1894 * Code generator attributes follow the usual underscore convention:
  1895     code_unfold     replaces    code unfold
  1896     code_post       replaces    code post
  1897     etc.
  1898   INCOMPATIBILITY.
  1899 
  1900 * Renamed methods:
  1901     sizechange -> size_change
  1902     induct_scheme -> induction_schema
  1903   INCOMPATIBILITY.
  1904 
  1905 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1906 INCOMPATIBILITY, use "undefined" directly.
  1907 
  1908 * Renamed theorems:
  1909     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1910     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1911     Suc_plus1 -> Suc_eq_plus1
  1912     *anti_sym -> *antisym*
  1913     vector_less_eq_def -> vector_le_def
  1914   INCOMPATIBILITY.
  1915 
  1916 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1917 INCOMPATIBILITY.
  1918 
  1919 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1920 INCOMPATIBILITY.
  1921 
  1922 
  1923 *** HOLCF ***
  1924 
  1925 * Theory Representable defines a class "rep" of domains that are
  1926 representable (via an ep-pair) in the universal domain type "udom".
  1927 Instances are provided for all type constructors defined in HOLCF.
  1928 
  1929 * The 'new_domain' command is a purely definitional version of the
  1930 domain package, for representable domains.  Syntax is identical to the
  1931 old domain package.  The 'new_domain' package also supports indirect
  1932 recursion using previously-defined type constructors.  See
  1933 src/HOLCF/ex/New_Domain.thy for examples.
  1934 
  1935 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1936 on the left-hand side of an equation, and then performs
  1937 simplification.  Rewriting is done using rules declared with the
  1938 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1939 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1940 
  1941 * The pattern-match compiler in 'fixrec' can now handle constructors
  1942 with HOL function types.  Pattern-match combinators for the Pair
  1943 constructor are pre-configured.
  1944 
  1945 * The 'fixrec' package now produces better fixed-point induction rules
  1946 for mutually-recursive definitions:  Induction rules have conclusions
  1947 of the form "P foo bar" instead of "P <foo, bar>".
  1948 
  1949 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1950 been renamed to "below".  The name "below" now replaces "less" in many
  1951 theorem names.  (Legacy theorem names using "less" are still supported
  1952 as well.)
  1953 
  1954 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1955 patterns can be used to generate strictness rules, or to make
  1956 functions more strict (much like the bang-patterns supported by the
  1957 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1958 examples.
  1959 
  1960 
  1961 *** ML ***
  1962 
  1963 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1964 errors and run-time exceptions, including detailed source positions.
  1965 
  1966 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1967 identified entries, with some additional information such as source
  1968 position, logical grouping etc.
  1969 
  1970 * Theory and context data is now introduced by the simplified and
  1971 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1972 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1973 copy operation) is still available for some time.
  1974 
  1975 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1976 provides a high-level programming interface to synchronized state
  1977 variables with atomic update.  This works via pure function
  1978 application within a critical section -- its runtime should be as
  1979 short as possible; beware of deadlocks if critical code is nested,
  1980 either directly or indirectly via other synchronized variables!
  1981 
  1982 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1983 wraps raw ML references, explicitly indicating their non-thread-safe
  1984 behaviour.  The Isar toplevel keeps this structure open, to
  1985 accommodate Proof General as well as quick and dirty interactive
  1986 experiments with references.
  1987 
  1988 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1989 parallel tactical reasoning.
  1990 
  1991 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1992 are similar to SUBPROOF, but are slightly more flexible: only the
  1993 specified parts of the subgoal are imported into the context, and the
  1994 body tactic may introduce new subgoals and schematic variables.
  1995 
  1996 * Old tactical METAHYPS, which does not observe the proof context, has
  1997 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1998 or Subgoal.FOCUS etc.
  1999 
  2000 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  2001 functors have their own ML name space there is no point to mark them
  2002 separately.)  Minor INCOMPATIBILITY.
  2003 
  2004 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  2005 
  2006 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  2007 INCOMPATIBILITY.
  2008 
  2009 * Operations of structure Skip_Proof no longer require quick_and_dirty
  2010 mode, which avoids critical setmp.
  2011 
  2012 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  2013 combinators for "args".  INCOMPATIBILITY, need to use simplified
  2014 Attrib/Method.setup introduced in Isabelle2009.
  2015 
  2016 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  2017 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  2018 last resort.  INCOMPATIBILITY.
  2019 
  2020 * Display.pretty_thm now requires a proper context (cf. former
  2021 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  2022 or even Display.pretty_thm_without_context as last resort.
  2023 INCOMPATIBILITY.
  2024 
  2025 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  2026 Syntax.pretty_typ/term directly, preferably with proper context
  2027 instead of global theory.
  2028 
  2029 
  2030 *** System ***
  2031 
  2032 * Further fine tuning of parallel proof checking, scales up to 8 cores
  2033 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  2034 usedir option -q.
  2035 
  2036 * Support for additional "Isabelle components" via etc/components, see
  2037 also the system manual.
  2038 
  2039 * The isabelle makeall tool now operates on all components with
  2040 IsaMakefile, not just hardwired "logics".
  2041 
  2042 * Removed "compress" option from isabelle-process and isabelle usedir;
  2043 this is always enabled.
  2044 
  2045 * Discontinued support for Poly/ML 4.x versions.
  2046 
  2047 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  2048 on a given logic image.  This requires the lighttpd webserver and is
  2049 currently supported on Linux only.
  2050 
  2051 
  2052 
  2053 New in Isabelle2009 (April 2009)
  2054 --------------------------------
  2055 
  2056 *** General ***
  2057 
  2058 * Simplified main Isabelle executables, with less surprises on
  2059 case-insensitive file-systems (such as Mac OS).
  2060 
  2061   - The main Isabelle tool wrapper is now called "isabelle" instead of
  2062     "isatool."
  2063 
  2064   - The former "isabelle" alias for "isabelle-process" has been
  2065     removed (should rarely occur to regular users).
  2066 
  2067   - The former "isabelle-interface" and its alias "Isabelle" have been
  2068     removed (interfaces are now regular Isabelle tools).
  2069 
  2070 Within scripts and make files, the Isabelle environment variables
  2071 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  2072 respectively.  (The latter are still available as legacy feature.)
  2073 
  2074 The old isabelle-interface wrapper could react in confusing ways if
  2075 the interface was uninstalled or changed otherwise.  Individual
  2076 interface tool configuration is now more explicit, see also the
  2077 Isabelle system manual.  In particular, Proof General is now available
  2078 via "isabelle emacs".
  2079 
  2080 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  2081 purge installed copies of Isabelle executables and re-run "isabelle
  2082 install -p ...", or use symlinks.
  2083 
  2084 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  2085 old ~/isabelle, which was slightly non-standard and apt to cause
  2086 surprises on case-insensitive file-systems (such as Mac OS).
  2087 
  2088 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  2089 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  2090 care is required when using older releases of Isabelle.  Note that
  2091 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  2092 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  2093 
  2094 * Proofs of fully specified statements are run in parallel on
  2095 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  2096 a regular 4-core machine, if the initial heap space is made reasonably
  2097 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  2098 
  2099 * The main reference manuals ("isar-ref", "implementation", and
  2100 "system") have been updated and extended.  Formally checked references
  2101 as hyperlinks are now available uniformly.
  2102 
  2103 
  2104 *** Pure ***
  2105 
  2106 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  2107 respects.  The most important changes are listed below.  See the
  2108 Tutorial on Locales ("locales" manual) for details.
  2109 
  2110 - In locale expressions, instantiation replaces renaming.  Parameters
  2111 must be declared in a for clause.  To aid compatibility with previous
  2112 parameter inheritance, in locale declarations, parameters that are not
  2113 'touched' (instantiation position "_" or omitted) are implicitly added
  2114 with their syntax at the beginning of the for clause.
  2115 
  2116 - Syntax from abbreviations and definitions in locales is available in
  2117 locale expressions and context elements.  The latter is particularly
  2118 useful in locale declarations.
  2119 
  2120 - More flexible mechanisms to qualify names generated by locale
  2121 expressions.  Qualifiers (prefixes) may be specified in locale
  2122 expressions, and can be marked as mandatory (syntax: "name!:") or
  2123 optional (syntax "name?:").  The default depends for plain "name:"
  2124 depends on the situation where a locale expression is used: in
  2125 commands 'locale' and 'sublocale' prefixes are optional, in
  2126 'interpretation' and 'interpret' prefixes are mandatory.  The old
  2127 implicit qualifiers derived from the parameter names of a locale are
  2128 no longer generated.
  2129 
  2130 - Command "sublocale l < e" replaces "interpretation l < e".  The
  2131 instantiation clause in "interpretation" and "interpret" (square
  2132 brackets) is no longer available.  Use locale expressions.
  2133 
  2134 - When converting proof scripts, mandatory qualifiers in
  2135 'interpretation' and 'interpret' should be retained by default, even
  2136 if this is an INCOMPATIBILITY compared to former behavior.  In the
  2137 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  2138 in locale expressions range over a single locale instance only.
  2139 
  2140 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  2141 In existing theorem specifications replace the includes element by the
  2142 respective context elements of the included locale, omitting those
  2143 that are already present in the theorem specification.  Multiple
  2144 assume elements of a locale should be replaced by a single one
  2145 involving the locale predicate.  In the proof body, declarations (most
  2146 notably theorems) may be regained by interpreting the respective
  2147 locales in the proof context as required (command "interpret").
  2148 
  2149 If using "includes" in replacement of a target solely because the
  2150 parameter types in the theorem are not as general as in the target,
  2151 consider declaring a new locale with additional type constraints on
  2152 the parameters (context element "constrains").
  2153 
  2154 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2155 
  2156 - Locale interpretation commands no longer attempt to simplify goal.
  2157 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2158 methods intro_locales and unfold_locales to clarify.
  2159 
  2160 - Locale interpretation commands no longer accept interpretation
  2161 attributes.  INCOMPATIBILITY.
  2162 
  2163 * Class declaration: so-called "base sort" must not be given in import
  2164 list any longer, but is inferred from the specification.  Particularly
  2165 in HOL, write
  2166 
  2167     class foo = ...
  2168 
  2169 instead of
  2170 
  2171     class foo = type + ...
  2172 
  2173 * Class target: global versions of theorems stemming do not carry a
  2174 parameter prefix any longer.  INCOMPATIBILITY.
  2175 
  2176 * Class 'instance' command no longer accepts attached definitions.
  2177 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2178 
  2179 * Recovered hiding of consts, which was accidentally broken in
  2180 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2181 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2182 
  2183 * Slightly more coherent Pure syntax, with updated documentation in
  2184 isar-ref manual.  Removed locales meta_term_syntax and
  2185 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2186 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2187 directly in regular applications.
  2188 
  2189 * There is a new syntactic category "float_const" for signed decimal
  2190 fractions (e.g. 123.45 or -123.45).
  2191 
  2192 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2193 interface with 'setup' command instead.
  2194 
  2195 * Command 'local_setup' is similar to 'setup', but operates on a local
  2196 theory context.
  2197 
  2198 * The 'axiomatization' command now only works within a global theory
  2199 context.  INCOMPATIBILITY.
  2200 
  2201 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2202 hypotheses.  Sorts required in the course of reasoning need to be
  2203 covered by the constraints in the initial statement, completed by the
  2204 type instance information of the background theory.  Non-trivial sort
  2205 hypotheses, which rarely occur in practice, may be specified via
  2206 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2207 
  2208   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2209 
  2210 The result contains an implicit sort hypotheses as before --
  2211 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2212 normalization.
  2213 
  2214 * Generalized Isar history, with support for linear undo, direct state
  2215 addressing etc.
  2216 
  2217 * Changed defaults for unify configuration options:
  2218 
  2219   unify_trace_bound = 50 (formerly 25)
  2220   unify_search_bound = 60 (formerly 30)
  2221 
  2222 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2223 
  2224   a) On theory merge, the last set of code equations for a particular
  2225      constant is taken (in accordance with the policy applied by other
  2226      parts of the code generator framework).
  2227 
  2228   b) Code equations stemming from explicit declarations (e.g. code
  2229      attribute) gain priority over default code equations stemming
  2230      from definition, primrec, fun etc.
  2231 
  2232 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2233 
  2234 * Unified theorem tables for both code generators.  Thus [code
  2235 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2236 
  2237 * Command 'find_consts' searches for constants based on type and name
  2238 patterns, e.g.
  2239 
  2240     find_consts "_ => bool"
  2241 
  2242 By default, matching is against subtypes, but it may be restricted to
  2243 the whole type.  Searching by name is possible.  Multiple queries are
  2244 conjunctive and queries may be negated by prefixing them with a
  2245 hyphen:
  2246 
  2247     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2248 
  2249 * New 'find_theorems' criterion "solves" matches theorems that
  2250 directly solve the current goal (modulo higher-order unification).
  2251 
  2252 * Auto solve feature for main theorem statements: whenever a new goal
  2253 is stated, "find_theorems solves" is called; any theorems that could
  2254 solve the lemma directly are listed as part of the goal state.
  2255 Cf. associated options in Proof General Isabelle settings menu,
  2256 enabled by default, with reasonable timeout for pathological cases of
  2257 higher-order unification.
  2258 
  2259 
  2260 *** Document preparation ***
  2261 
  2262 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2263 demanding keyword 'by' and supporting the full method expression
  2264 syntax just like the Isar command 'by'.
  2265 
  2266 
  2267 *** HOL ***
  2268 
  2269 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2270 points Main and Complex_Main remain as before.
  2271 
  2272 * Logic image HOL-Plain provides a minimal HOL with the most important
  2273 tools available (inductive, datatype, primrec, ...).  This facilitates
  2274 experimentation and tool development.  Note that user applications
  2275 (and library theories) should never refer to anything below theory
  2276 Main, as before.
  2277 
  2278 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2279 experimentation due to shorter build times.
  2280 
  2281 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2282 were previously part of former HOL-Complex.  Entry point Hyperreal
  2283 remains valid, but theories formerly using Complex_Main should now use
  2284 new entry point Hypercomplex.
  2285 
  2286 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2287 Posix processes.  Avoids potentially expensive forking of the ML
  2288 process.  New thread-based implementation also works on non-Unix
  2289 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2290 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2291 commands are covered in the isar-ref manual.
  2292 
  2293 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2294 sledgehammer without local ATP installation (Vampire etc.). Other
  2295 provers may be included via suitable ML wrappers, see also
  2296 src/HOL/ATP_Linkup.thy.
  2297 
  2298 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2299 menu.
  2300 
  2301 * The metis method no longer fails because the theorem is too trivial
  2302 (contains the empty clause).
  2303 
  2304 * The metis method now fails in the usual manner, rather than raising
  2305 an exception, if it determines that it cannot prove the theorem.
  2306 
  2307 * Method "coherent" implements a prover for coherent logic (see also
  2308 src/Tools/coherent.ML).
  2309 
  2310 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2311 "undefined" is the right choice to replace "arbitrary", though
  2312 logically there is no difference.  INCOMPATIBILITY.
  2313 
  2314 * Command "value" now integrates different evaluation mechanisms.  The
  2315 result of the first successful evaluation mechanism is printed.  In
  2316 square brackets a particular named evaluation mechanisms may be
  2317 specified (currently, [SML], [code] or [nbe]).  See further
  2318 src/HOL/ex/Eval_Examples.thy.
  2319 
  2320 * Normalization by evaluation now allows non-leftlinear equations.
  2321 Declare with attribute [code nbe].
  2322 
  2323 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2324 as the structured Isar versions "cases" and "induct", cf. the
  2325 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2326 are now presented as a list of individual projections
  2327 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2328 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2329 rare situations a different rule is selected --- notably nested tuple
  2330 elimination instead of former prod.exhaust: use explicit (case_tac t
  2331 rule: prod.exhaust) here.
  2332 
  2333 * Attributes "cases", "induct", "coinduct" support "del" option.
  2334 
  2335 * Removed fact "case_split_thm", which duplicates "case_split".
  2336 
  2337 * The option datatype has been moved to a new theory Option.  Renamed
  2338 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2339 
  2340 * New predicate "strict_mono" classifies strict functions on partial
  2341 orders.  With strict functions on linear orders, reasoning about
  2342 (in)equalities is facilitated by theorems "strict_mono_eq",
  2343 "strict_mono_less_eq" and "strict_mono_less".
  2344 
  2345 * Some set operations are now proper qualified constants with
  2346 authentic syntax.  INCOMPATIBILITY:
  2347 
  2348     op Int ~>   Set.Int
  2349     op Un ~>    Set.Un
  2350     INTER ~>    Set.INTER
  2351     UNION ~>    Set.UNION
  2352     Inter ~>    Set.Inter
  2353     Union ~>    Set.Union
  2354     {} ~>       Set.empty
  2355     UNIV ~>     Set.UNIV
  2356 
  2357 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2358 theory Set.
  2359 
  2360 * Auxiliary class "itself" has disappeared -- classes without any
  2361 parameter are treated as expected by the 'class' command.
  2362 
  2363 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2364 
  2365 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2366 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2367 
  2368 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2369 method "approximation".  It proves formulas on real values by using
  2370 interval arithmetic.  In the formulas are also the transcendental
  2371 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2372 allowed. For examples see
  2373 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2374 
  2375 * Theory "Reflection" now resides in HOL/Library.
  2376 
  2377 * Entry point to Word library now simply named "Word".
  2378 INCOMPATIBILITY.
  2379 
  2380 * Made source layout more coherent with logical distribution
  2381 structure:
  2382 
  2383     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2384     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2385     src/HOL/Library/GCD.thy ~> src/HOL/
  2386     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2387     src/HOL/Library/Parity.thy ~> src/HOL/
  2388     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2389     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2390     src/HOL/Real/Lubs.thy ~> src/HOL/
  2391     src/HOL/Real/PReal.thy ~> src/HOL/
  2392     src/HOL/Real/Rational.thy ~> src/HOL/
  2393     src/HOL/Real/RComplete.thy ~> src/HOL/
  2394     src/HOL/Real/RealDef.thy ~> src/HOL/
  2395     src/HOL/Real/RealPow.thy ~> src/HOL/
  2396     src/HOL/Real/Real.thy ~> src/HOL/
  2397     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2398     src/HOL/Complex/Complex.thy ~> src/HOL/
  2399     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2400     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2401     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2402     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2403     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2404     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2405     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2406     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2407     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2408     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2409     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2410     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2411     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2412     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2413     src/HOL/Real/Float ~> src/HOL/Library/
  2414     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2415     src/HOL/Real/RealVector.thy ~> src/HOL/
  2416 
  2417     src/HOL/arith_data.ML ~> src/HOL/Tools
  2418     src/HOL/hologic.ML ~> src/HOL/Tools
  2419     src/HOL/simpdata.ML ~> src/HOL/Tools
  2420     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2421     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2422     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2423     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2424     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2425     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2426     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2427 
  2428     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2429     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2430     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2431     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2432     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2433     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2434 
  2435 * If methods "eval" and "evaluation" encounter a structured proof
  2436 state with !!/==>, only the conclusion is evaluated to True (if
  2437 possible), avoiding strange error messages.
  2438 
  2439 * Method "sizechange" automates termination proofs using (a
  2440 modification of) the size-change principle.  Requires SAT solver.  See
  2441 src/HOL/ex/Termination.thy for examples.
  2442 
  2443 * Simplifier: simproc for let expressions now unfolds if bound
  2444 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2445 
  2446 * Method "arith": Linear arithmetic now ignores all inequalities when
  2447 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2448 
  2449 * New attribute "arith" for facts that should always be used
  2450 automatically by arithmetic. It is intended to be used locally in
  2451 proofs, e.g.
  2452 
  2453   assumes [arith]: "x > 0"
  2454 
  2455 Global usage is discouraged because of possible performance impact.
  2456 
  2457 * New classes "top" and "bot" with corresponding operations "top" and
  2458 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2459 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2460 
  2461 * Changed definition lemma "less_fun_def" in order to provide an
  2462 instance for preorders on functions; use lemma "less_le" instead.
  2463 INCOMPATIBILITY.
  2464 
  2465 * Theory Orderings: class "wellorder" moved here, with explicit
  2466 induction rule "less_induct" as assumption.  For instantiation of
  2467 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2468 INCOMPATIBILITY.
  2469 
  2470 * Theory Orderings: added class "preorder" as superclass of "order".
  2471 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2472 etc. slightly changed.  Some theorems named order_class.* now named
  2473 preorder_class.*.
  2474 
  2475 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2476 "diag" to "Id_on".
  2477 
  2478 * Theory Finite_Set: added a new fold combinator of type
  2479 
  2480   ('a => 'b => 'b) => 'b => 'a set => 'b
  2481 
  2482 Occasionally this is more convenient than the old fold combinator
  2483 which is now defined in terms of the new one and renamed to
  2484 fold_image.
  2485 
  2486 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2487 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2488 extended with further lemmas!).  At the moment both still exist but
  2489 the former will disappear at some point.
  2490 
  2491 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2492 class recpower.  Type-specific simp rules for various recpower types
  2493 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2494 
  2495 rat_power_0    -> power_0
  2496 rat_power_Suc  -> power_Suc
  2497 realpow_0      -> power_0
  2498 realpow_Suc    -> power_Suc
  2499 complexpow_0   -> power_0
  2500 complexpow_Suc -> power_Suc
  2501 power_poly_0   -> power_0
  2502 power_poly_Suc -> power_Suc
  2503 
  2504 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2505 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2506 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2507 of lemmas from Divides has been generalized from nat to class
  2508 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2509 renames resulting from duplicate elimination:
  2510 
  2511     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2512     zero_dvd_iff ~>         dvd_0_left_iff
  2513     dvd_0 ~>                dvd_0_right
  2514     DIVISION_BY_ZERO_DIV ~> div_by_0
  2515     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2516     mult_div ~>             div_mult_self2_is_id
  2517     mult_mod ~>             mod_mult_self2_is_0
  2518 
  2519 * Theory IntDiv: removed many lemmas that are instances of class-based
  2520 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2521 rename old lemmas as follows:
  2522 
  2523 dvd_diff               -> nat_dvd_diff
  2524 dvd_zminus_iff         -> dvd_minus_iff
  2525 mod_add1_eq            -> mod_add_eq
  2526 mod_mult1_eq           -> mod_mult_right_eq
  2527 mod_mult1_eq'          -> mod_mult_left_eq
  2528 mod_mult_distrib_mod   -> mod_mult_eq
  2529 nat_mod_add_left_eq    -> mod_add_left_eq
  2530 nat_mod_add_right_eq   -> mod_add_right_eq
  2531 nat_mod_div_trivial    -> mod_div_trivial
  2532 nat_mod_mod_trivial    -> mod_mod_trivial
  2533 zdiv_zadd_self1        -> div_add_self1
  2534 zdiv_zadd_self2        -> div_add_self2
  2535 zdiv_zmult_self1       -> div_mult_self2_is_id
  2536 zdiv_zmult_self2       -> div_mult_self1_is_id
  2537 zdvd_triv_left         -> dvd_triv_left
  2538 zdvd_triv_right        -> dvd_triv_right
  2539 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2540 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2541 zmod_zadd_left_eq      -> mod_add_left_eq
  2542 zmod_zadd_right_eq     -> mod_add_right_eq
  2543 zmod_zadd_self1        -> mod_add_self1
  2544 zmod_zadd_self2        -> mod_add_self2
  2545 zmod_zadd1_eq          -> mod_add_eq
  2546 zmod_zdiff1_eq         -> mod_diff_eq
  2547 zmod_zdvd_zmod         -> mod_mod_cancel
  2548 zmod_zmod_cancel       -> mod_mod_cancel
  2549 zmod_zmult_self1       -> mod_mult_self2_is_0
  2550 zmod_zmult_self2       -> mod_mult_self1_is_0
  2551 zmod_1                 -> mod_by_1
  2552 zdiv_1                 -> div_by_1
  2553 zdvd_abs1              -> abs_dvd_iff
  2554 zdvd_abs2              -> dvd_abs_iff
  2555 zdvd_refl              -> dvd_refl
  2556 zdvd_trans             -> dvd_trans
  2557 zdvd_zadd              -> dvd_add
  2558 zdvd_zdiff             -> dvd_diff
  2559 zdvd_zminus_iff        -> dvd_minus_iff
  2560 zdvd_zminus2_iff       -> minus_dvd_iff
  2561 zdvd_zmultD            -> dvd_mult_right
  2562 zdvd_zmultD2           -> dvd_mult_left
  2563 zdvd_zmult_mono        -> mult_dvd_mono
  2564 zdvd_0_right           -> dvd_0_right
  2565 zdvd_0_left            -> dvd_0_left_iff
  2566 zdvd_1_left            -> one_dvd
  2567 zminus_dvd_iff         -> minus_dvd_iff
  2568 
  2569 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2570 
  2571 * The real numbers offer decimal input syntax: 12.34 is translated
  2572 into 1234/10^2. This translation is not reversed upon output.
  2573 
  2574 * Theory Library/Polynomial defines an abstract type 'a poly of
  2575 univariate polynomials with coefficients of type 'a.  In addition to
  2576 the standard ring operations, it also supports div and mod.  Code
  2577 generation is also supported, using list-style constructors.
  2578 
  2579 * Theory Library/Inner_Product defines a class of real_inner for real
  2580 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2581 => real.  Class real_inner is a subclass of real_normed_vector from
  2582 theory RealVector.
  2583 
  2584 * Theory Library/Product_Vector provides instances for the product
  2585 type 'a * 'b of several classes from RealVector and Inner_Product.
  2586 Definitions of addition, subtraction, scalar multiplication, norms,
  2587 and inner products are included.
  2588 
  2589 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2590 addition to the field operations, numerals and case syntax are also
  2591 supported.
  2592 
  2593 * Theory Library/Diagonalize provides constructive version of Cantor's
  2594 first diagonalization argument.
  2595 
  2596 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2597 zlcm (for int); carried together from various gcd/lcm developements in
  2598 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2599 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2600 may recover tupled syntax as follows:
  2601 
  2602     hide (open) const gcd
  2603     abbreviation gcd where
  2604       "gcd == (%(a, b). GCD.gcd a b)"
  2605     notation (output)
  2606       GCD.gcd ("gcd '(_, _')")
  2607 
  2608 The same works for lcm, zgcd, zlcm.
  2609 
  2610 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2611 instantiations for algebraic structures.  Removed some duplicate
  2612 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2613 
  2614 * ML antiquotation @{code} takes a constant as argument and generates
  2615 corresponding code in background and inserts name of the corresponding
  2616 resulting ML value/function/datatype constructor binding in place.
  2617 All occurrences of @{code} with a single ML block are generated
  2618 simultaneously.  Provides a generic and safe interface for
  2619 instrumentalizing code generation.  See
  2620 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2621 In future you ought to refrain from ad-hoc compiling generated SML
  2622 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2623 cannot refer to constants for which user-defined serializations are
  2624 set.  Refer to the corresponding ML counterpart directly in that
  2625 cases.
  2626 
  2627 * Command 'rep_datatype': instead of theorem names the command now
  2628 takes a list of terms denoting the constructors of the type to be
  2629 represented as datatype.  The characteristic theorems have to be
  2630 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2631 have disappeared in favour of existing ones:
  2632 
  2633     unit_induct                 ~> unit.induct
  2634     prod_induct                 ~> prod.induct
  2635     sum_induct                  ~> sum.induct
  2636     Suc_Suc_eq                  ~> nat.inject
  2637     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2638 
  2639 
  2640 *** HOL-Algebra ***
  2641 
  2642 * New locales for orders and lattices where the equivalence relation
  2643 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2644 locales use a record structure with field eq for the equivalence.
  2645 
  2646 * New theory of factorial domains.
  2647 
  2648 * Units_l_inv and Units_r_inv are now simp rules by default.
  2649 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2650 and/or r_inv will now also require deletion of these lemmas.
  2651 
  2652 * Renamed the following theorems, INCOMPATIBILITY:
  2653 
  2654 UpperD ~> Upper_memD
  2655 LowerD ~> Lower_memD
  2656 least_carrier ~> least_closed
  2657 greatest_carrier ~> greatest_closed
  2658 greatest_Lower_above ~> greatest_Lower_below
  2659 one_zero ~> carrier_one_zero
  2660 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2661 
  2662 
  2663 *** HOL-Nominal ***
  2664 
  2665 * Nominal datatypes can now contain type-variables.
  2666 
  2667 * Commands 'nominal_inductive' and 'equivariance' work with local
  2668 theory targets.
  2669 
  2670 * Nominal primrec can now works with local theory targets and its
  2671 specification syntax now conforms to the general format as seen in
  2672 'inductive' etc.
  2673 
  2674 * Method "perm_simp" honours the standard simplifier attributes
  2675 (no_asm), (no_asm_use) etc.
  2676 
  2677 * The new predicate #* is defined like freshness, except that on the
  2678 left hand side can be a set or list of atoms.
  2679 
  2680 * Experimental command 'nominal_inductive2' derives strong induction
  2681 principles for inductive definitions.  In contrast to
  2682 'nominal_inductive', which can only deal with a fixed number of
  2683 binders, it can deal with arbitrary expressions standing for sets of
  2684 atoms to be avoided.  The only inductive definition we have at the
  2685 moment that needs this generalisation is the typing rule for Lets in
  2686 the algorithm W:
  2687 
  2688  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2689  -----------------------------------------------------------------
  2690          Gamma |- Let x be t1 in t2 : T2
  2691 
  2692 In this rule one wants to avoid all the binders that are introduced by
  2693 "close Gamma T1".  We are looking for other examples where this
  2694 feature might be useful.  Please let us know.
  2695 
  2696 
  2697 *** HOLCF ***
  2698 
  2699 * Reimplemented the simplification procedure for proving continuity
  2700 subgoals.  The new simproc is extensible; users can declare additional
  2701 continuity introduction rules with the attribute [cont2cont].
  2702 
  2703 * The continuity simproc now uses a different introduction rule for
  2704 solving continuity subgoals on terms with lambda abstractions.  In
  2705 some rare cases the new simproc may fail to solve subgoals that the
  2706 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2707 Potential INCOMPATIBILITY.
  2708 
  2709 * Command 'fixrec': specification syntax now conforms to the general
  2710 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2711 examples.  INCOMPATIBILITY.
  2712 
  2713 
  2714 *** ZF ***
  2715 
  2716 * Proof of Zorn's Lemma for partial orders.
  2717 
  2718 
  2719 *** ML ***
  2720 
  2721 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2722 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2723 depends on multithreading, so timouts will not work before Poly/ML
  2724 5.2.1!
  2725 
  2726 * High-level support for concurrent ML programming, see
  2727 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2728 particularly convenient to organize independent functional
  2729 computations.  The concept of "synchronized variables" provides a
  2730 higher-order interface for components with shared state, avoiding the
  2731 delicate details of mutexes and condition variables.  (Requires
  2732 Poly/ML 5.2.1 or later.)
  2733 
  2734 * ML bindings produced via Isar commands are stored within the Isar
  2735 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2736 become thread-safe and work with undo as expected (concerning
  2737 top-level bindings, not side-effects on global references).
  2738 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2739 compiler at runtime; really global bindings need to be given outside a
  2740 theory.  (Requires Poly/ML 5.2 or later.)
  2741 
  2742 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2743 context.  Top-level ML bindings are stored within the proof context in
  2744 a purely sequential fashion, disregarding the nested proof structure.
  2745 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2746 proof.  (Requires Poly/ML 5.2 or later.)
  2747 
  2748 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2749 and Method.setup, as well as Isar commands 'attribute_setup' and
  2750 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2751 existing code accordingly, or use plain 'setup' together with old
  2752 Method.add_method.
  2753 
  2754 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2755 to 'a -> thm, while results are always tagged with an authentic oracle
  2756 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2757 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2758 accordingly.  Note that extra performance may be gained by producing
  2759 the cterm carefully, avoiding slow Thm.cterm_of.
  2760 
  2761 * Simplified interface for defining document antiquotations via
  2762 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2763 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2764 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2765 examples.
  2766 
  2767 * More systematic treatment of long names, abstract name bindings, and
  2768 name space operations.  Basic operations on qualified names have been
  2769 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2770 Long_Name.append.  Old type bstring has been mostly replaced by
  2771 abstract type binding (see structure Binding), which supports precise
  2772 qualification by packages and local theory targets, as well as proper
  2773 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2774 bstring values into Binding.name, or better pass through abstract
  2775 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2776 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2777 
  2778 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2779 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2780 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2781 
  2782 * Disposed old type and term read functions (Sign.read_def_typ,
  2783 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2784 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2785 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2786 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2787 resort for legacy applications.
  2788 
  2789 * Disposed old declarations, tactics, tactic combinators that refer to
  2790 the simpset or claset of an implicit theory (such as Addsimps,
  2791 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2792 embedded ML text, or local_simpset_of with a proper context passed as
  2793 explicit runtime argument.
  2794 
  2795 * Rules and tactics that read instantiations (read_instantiate,
  2796 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2797 context, which is required for parsing and type-checking.  Moreover,
  2798 the variables are specified as plain indexnames, not string encodings
  2799 thereof.  INCOMPATIBILITY.
  2800 
  2801 * Generic Toplevel.add_hook interface allows to analyze the result of
  2802 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2803 for theorem dependency output of transactions resulting in a new
  2804 theory state.
  2805 
  2806 * ML antiquotations: block-structured compilation context indicated by
  2807 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2808 
  2809   @{binding name}                         - basic name binding
  2810   @{let ?pat = term}                      - term abbreviation (HO matching)
  2811   @{note name = fact}                     - fact abbreviation
  2812   @{thm fact}                             - singleton fact (with attributes)
  2813   @{thms fact}                            - general fact (with attributes)
  2814   @{lemma prop by method}                 - singleton goal
  2815   @{lemma prop by meth1 meth2}            - singleton goal
  2816   @{lemma prop1 ... propN by method}      - general goal
  2817   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2818   @{lemma (open) ...}                     - open derivation
  2819 
  2820 
  2821 *** System ***
  2822 
  2823 * The Isabelle "emacs" tool provides a specific interface to invoke
  2824 Proof General / Emacs, with more explicit failure if that is not
  2825 installed (the old isabelle-interface script silently falls back on
  2826 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2827 installation location of the Proof General distribution.
  2828 
  2829 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2830 the Isabelle process into a JVM/Scala application.  See
  2831 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2832 process wrapper has been discontinued.)
  2833 
  2834 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2835 
  2836 * Various status messages (with exact source position information) are
  2837 emitted, if proper markup print mode is enabled.  This allows
  2838 user-interface components to provide detailed feedback on internal
  2839 prover operations.
  2840 
  2841 
  2842 
  2843 New in Isabelle2008 (June 2008)
  2844 -------------------------------
  2845 
  2846 *** General ***
  2847 
  2848 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2849 and updated, with formally checked references as hyperlinks.
  2850 
  2851 * Theory loader: use_thy (and similar operations) no longer set the
  2852 implicit ML context, which was occasionally hard to predict and in
  2853 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2854 provides a proper context already.
  2855 
  2856 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2857 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2858 'use' within a theory file will do the job.
  2859 
  2860 * Name space merge now observes canonical order, i.e. the second space
  2861 is inserted into the first one, while existing entries in the first
  2862 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2863 swap theory imports.
  2864 
  2865 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2866 INCOMPATIBILITY in identifier syntax etc.
  2867 
  2868 * Outer syntax: string tokens no longer admit escaped white space,
  2869 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2870 white space without escapes.
  2871 
  2872 * Outer syntax: string tokens may contain arbitrary character codes
  2873 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2874 "foo_bar".
  2875 
  2876 
  2877 *** Pure ***
  2878 
  2879 * Context-dependent token translations.  Default setup reverts locally
  2880 fixed variables, and adds hilite markup for undeclared frees.
  2881 
  2882 * Unused theorems can be found using the new command 'unused_thms'.
  2883 There are three ways of invoking it:
  2884 
  2885 (1) unused_thms
  2886      Only finds unused theorems in the current theory.
  2887 
  2888 (2) unused_thms thy_1 ... thy_n -
  2889      Finds unused theorems in the current theory and all of its ancestors,
  2890      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2891 
  2892 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2893      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2894      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2895      their ancestors.
  2896 
  2897 In order to increase the readability of the list produced by
  2898 unused_thms, theorems that have been created by a particular instance
  2899 of a theory command such as 'inductive' or 'function' are considered
  2900 to belong to the same "group", meaning that if at least one theorem in
  2901 this group is used, the other theorems in the same group are no longer
  2902 reported as unused.  Moreover, if all theorems in the group are
  2903 unused, only one theorem in the group is displayed.
  2904 
  2905 Note that proof objects have to be switched on in order for
  2906 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2907 usually the case when using Proof General with the default settings).
  2908 
  2909 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2910 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2911 duplicate fact bindings, or even accidental fact duplications.  Note
  2912 that tools may maintain dynamically scoped facts systematically, using
  2913 PureThy.add_thms_dynamic.
  2914 
  2915 * Command 'hide' now allows to hide from "fact" name space as well.
  2916 
  2917 * Eliminated destructive theorem database, simpset, claset, and
  2918 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2919 update of theories within ML code.
  2920 
  2921 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2922 INCOMPATIBILITY, object-logics depending on former Pure require
  2923 additional setup PureThy.old_appl_syntax_setup; object-logics
  2924 depending on former CPure need to refer to Pure.
  2925 
  2926 * Commands 'use' and 'ML' are now purely functional, operating on
  2927 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2928 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2929 INCOMPATIBILITY.
  2930 
  2931 * Command 'setup': discontinued implicit version with ML reference.
  2932 
  2933 * Instantiation target allows for simultaneous specification of class
  2934 instance operations together with an instantiation proof.
  2935 Type-checking phase allows to refer to class operations uniformly.
  2936 See src/HOL/Complex/Complex.thy for an Isar example and
  2937 src/HOL/Library/Eval.thy for an ML example.
  2938 
  2939 * Indexing of literal facts: be more serious about including only
  2940 facts from the visible specification/proof context, but not the
  2941 background context (locale etc.).  Affects `prop` notation and method
  2942 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2943 situations.
  2944 
  2945 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2946 "(open)" option, which used to expose internal bound variables to the
  2947 proof text.
  2948 
  2949 * Isar statements: removed obsolete case "rule_context".
  2950 INCOMPATIBILITY, better use explicit fixes/assumes.
  2951 
  2952 * Locale proofs: default proof step now includes 'unfold_locales';
  2953 hence 'proof' without argument may be used to unfold locale
  2954 predicates.
  2955 
  2956 
  2957 *** Document preparation ***
  2958 
  2959 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2960 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2961 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2962 spot); renamed link color from "darkblue" to "linkcolor" (default
  2963 value unchanged, can be redefined via \definecolor); no longer sets
  2964 "a4paper" option (unnecessary or even intrusive).
  2965 
  2966 * Antiquotation @{lemma A method} proves proposition A by the given
  2967 method (either a method name or a method name plus (optional) method
  2968 arguments in parentheses) and prints A just like @{prop A}.
  2969 
  2970 
  2971 *** HOL ***
  2972 
  2973 * New primrec package.  Specification syntax conforms in style to
  2974 definition/function/....  No separate induction rule is provided.  The
  2975 "primrec" command distinguishes old-style and new-style specifications
  2976 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2977 When adjusting theories, beware: constants stemming from new-style
  2978 primrec specifications have authentic syntax.
  2979 
  2980 * Metis prover is now an order of magnitude faster, and also works
  2981 with multithreading.
  2982 
  2983 * Metis: the maximum number of clauses that can be produced from a
  2984 theorem is now given by the attribute max_clauses.  Theorems that
  2985 exceed this number are ignored, with a warning printed.
  2986 
  2987 * Sledgehammer no longer produces structured proofs by default. To
  2988 enable, declare [[sledgehammer_full = true]].  Attributes
  2989 reconstruction_modulus, reconstruction_sorts renamed
  2990 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2991 
  2992 * Method "induct_scheme" derives user-specified induction rules
  2993 from well-founded induction and completeness of patterns. This factors
  2994 out some operations that are done internally by the function package
  2995 and makes them available separately.  See
  2996 src/HOL/ex/Induction_Scheme.thy for examples.
  2997 
  2998 * More flexible generation of measure functions for termination
  2999 proofs: Measure functions can be declared by proving a rule of the
  3000 form "is_measure f" and giving it the [measure_function] attribute.
  3001 The "is_measure" predicate is logically meaningless (always true), and
  3002 just guides the heuristic.  To find suitable measure functions, the
  3003 termination prover sets up the goal "is_measure ?f" of the appropriate
  3004 type and generates all solutions by prolog-style backwards proof using
  3005 the declared rules.
  3006 
  3007 This setup also deals with rules like 
  3008 
  3009   "is_measure f ==> is_measure (list_size f)"
  3010 
  3011 which accommodates nested datatypes that recurse through lists.
  3012 Similar rules are predeclared for products and option types.
  3013 
  3014 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  3015 
  3016   INCOMPATIBILITIES:
  3017 
  3018   - Definitions of overloaded constants on sets have to be replaced by
  3019     definitions on => and bool.
  3020 
  3021   - Some definitions of overloaded operators on sets can now be proved
  3022     using the definitions of the operators on => and bool.  Therefore,
  3023     the following theorems have been renamed:
  3024 
  3025       subset_def   -> subset_eq
  3026       psubset_def  -> psubset_eq
  3027       set_diff_def -> set_diff_eq
  3028       Compl_def    -> Compl_eq
  3029       Sup_set_def  -> Sup_set_eq
  3030       Inf_set_def  -> Inf_set_eq
  3031       sup_set_def  -> sup_set_eq
  3032       inf_set_def  -> inf_set_eq
  3033 
  3034   - Due to the incompleteness of the HO unification algorithm, some
  3035     rules such as subst may require manual instantiation, if some of
  3036     the unknowns in the rule is a set.
  3037 
  3038   - Higher order unification and forward proofs:
  3039     The proof pattern
  3040 
  3041       have "P (S::'a set)" <...>
  3042       then have "EX S. P S" ..
  3043 
  3044     no longer works (due to the incompleteness of the HO unification
  3045     algorithm) and must be replaced by the pattern
  3046 
  3047       have "EX S. P S"
  3048       proof
  3049         show "P S" <...>
  3050       qed
  3051 
  3052   - Calculational reasoning with subst (or similar rules):
  3053     The proof pattern
  3054 
  3055       have "P (S::'a set)" <...>
  3056       also have "S = T" <...>
  3057       finally have "P T" .
  3058 
  3059     no longer works (for similar reasons as the previous example) and
  3060     must be replaced by something like
  3061 
  3062       have "P (S::'a set)" <...>
  3063       moreover have "S = T" <...>
  3064       ultimately have "P T" by simp
  3065 
  3066   - Tactics or packages written in ML code:
  3067     Code performing pattern matching on types via
  3068 
  3069       Type ("set", [T]) => ...
  3070 
  3071     must be rewritten. Moreover, functions like strip_type or
  3072     binder_types no longer return the right value when applied to a
  3073     type of the form
  3074 
  3075       T1 => ... => Tn => U => bool
  3076 
  3077     rather than
  3078 
  3079       T1 => ... => Tn => U set
  3080 
  3081 * Merged theories Wellfounded_Recursion, Accessible_Part and
  3082 Wellfounded_Relations to theory Wellfounded.
  3083 
  3084 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  3085 
  3086 * Class finite no longer treats UNIV as class parameter.  Use class
  3087 enum from theory Library/Enum instead to achieve a similar effect.
  3088 INCOMPATIBILITY.
  3089 
  3090 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  3091 and "Cons".  INCOMPATIBILITY.
  3092 
  3093 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  3094 Potential INCOMPATIBILITY.
  3095 
  3096 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  3097 injective_fst_snd removed, use split_eta and prod_eqI instead.
  3098 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  3099 
  3100 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  3101 the same name in theory Orderings:
  3102 
  3103   less_trans
  3104   less_linear
  3105   le_imp_less_or_eq
  3106   le_less_trans
  3107   less_le_trans
  3108   less_not_sym
  3109   less_asym
  3110 
  3111 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  3112 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  3113 and different variable names.
  3114 
  3115 * Library/Option_ord.thy: Canonical order on option type.
  3116 
  3117 * Library/RBT.thy: Red-black trees, an efficient implementation of
  3118 finite maps.
  3119 
  3120 * Library/Countable.thy: Type class for countable types.
  3121 
  3122 * Theory Int: The representation of numerals has changed.  The infix
  3123 operator BIT and the bit datatype with constructors B0 and B1 have
  3124 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  3125 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  3126 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  3127 accordingly.
  3128 
  3129 * Theory Nat: definition of <= and < on natural numbers no longer
  3130 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  3131 le_def and less_def have disappeared.  Consider lemmas not_less
  3132 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  3133 
  3134 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  3135 (whose purpose mainly is for various fold_set functionals) have been
  3136 abandoned in favor of the existing algebraic classes
  3137 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  3138 lower_semilattice (resp. upper_semilattice) and linorder.
  3139 INCOMPATIBILITY.
  3140 
  3141 * Theory Transitive_Closure: induct and cases rules now declare proper
  3142 case_names ("base" and "step").  INCOMPATIBILITY.
  3143 
  3144 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  3145 lattices.  The form set-specific version is available as
  3146 Inductive.lfp_ordinal_induct_set.
  3147 
  3148 * Renamed theorems "power.simps" to "power_int.simps".
  3149 INCOMPATIBILITY.
  3150 
  3151 * Class semiring_div provides basic abstract properties of semirings
  3152 with division and modulo operations.  Subsumes former class dvd_mod.
  3153 
  3154 * Merged theories IntDef, Numeral and IntArith into unified theory
  3155 Int.  INCOMPATIBILITY.
  3156 
  3157 * Theory Library/Code_Index: type "index" now represents natural
  3158 numbers rather than integers.  INCOMPATIBILITY.
  3159 
  3160 * New class "uminus" with operation "uminus" (split of from class
  3161 "minus" which now only has operation "minus", binary).
  3162 INCOMPATIBILITY.
  3163 
  3164 * Constants "card", "internal_split", "option_map" now with authentic
  3165 syntax.  INCOMPATIBILITY.
  3166 
  3167 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3168 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3169 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3170 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3171 Sup_set_def, le_def, less_def, option_map_def now with object
  3172 equality.  INCOMPATIBILITY.
  3173 
  3174 * Records. Removed K_record, and replaced it by pure lambda term
  3175 %x. c. The simplifier setup is now more robust against eta expansion.
  3176 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3177 
  3178 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3179 
  3180 * Library/ListVector: new theory of arithmetic vector operations.
  3181 
  3182 * Library/Order_Relation: new theory of various orderings as sets of
  3183 pairs.  Defines preorders, partial orders, linear orders and
  3184 well-orders on sets and on types.
  3185 
  3186 
  3187 *** ZF ***
  3188 
  3189 * Renamed some theories to allow to loading both ZF and HOL in the
  3190 same session:
  3191 
  3192   Datatype  -> Datatype_ZF
  3193   Inductive -> Inductive_ZF
  3194   Int       -> Int_ZF
  3195   IntDiv    -> IntDiv_ZF
  3196   Nat       -> Nat_ZF
  3197   List      -> List_ZF
  3198   Main      -> Main_ZF
  3199 
  3200 INCOMPATIBILITY: ZF theories that import individual theories below
  3201 Main might need to be adapted.  Regular theory Main is still
  3202 available, as trivial extension of Main_ZF.
  3203 
  3204 
  3205 *** ML ***
  3206 
  3207 * ML within Isar: antiquotation @{const name} or @{const
  3208 name(typargs)} produces statically-checked Const term.
  3209 
  3210 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3211 (of the same name).  Removed obsolete print command.
  3212 
  3213 * Removed obsolete "use_legacy_bindings" function.
  3214 
  3215 * The ``print mode'' is now a thread-local value derived from a global
  3216 template (the former print_mode reference), thus access becomes
  3217 non-critical.  The global print_mode reference is for session
  3218 management only; user-code should use print_mode_value,
  3219 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3220 
  3221 * Functions system/system_out provide a robust way to invoke external
  3222 shell commands, with propagation of interrupts (requires Poly/ML
  3223 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3224 
  3225 
  3226 *** System ***
  3227 
  3228 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3229 in accordance with Proof General 3.7, which prefers GNU emacs.
  3230 
  3231 * isatool tty runs Isabelle process with plain tty interaction;
  3232 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3233 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3234 
  3235 * isatool browser now works with Cygwin as well, using general
  3236 "javapath" function defined in Isabelle process environment.
  3237 
  3238 * YXML notation provides a simple and efficient alternative to
  3239 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3240 isatool yxml as described in the Isabelle system manual.
  3241 
  3242 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3243 provides general wrapper for managing an Isabelle process in a robust
  3244 fashion, with ``cooked'' output from stdin/stderr.
  3245 
  3246 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3247 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3248 
  3249 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3250 way of changing the user's settings is via
  3251 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3252 script.
  3253 
  3254 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3255 cores of the underlying machine, which is a good starting point for
  3256 optimal performance tuning.  The corresponding usedir option -M allows
  3257 "max" as an alias for "0".  WARNING: does not work on certain versions
  3258 of Mac OS (with Poly/ML 5.1).
  3259 
  3260 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3261 adverse effect of Isabelle flooding interactive front-ends (notably
  3262 ProofGeneral / XEmacs).
  3263 
  3264 
  3265 
  3266 New in Isabelle2007 (November 2007)
  3267 -----------------------------------
  3268 
  3269 *** General ***
  3270 
  3271 * More uniform information about legacy features, notably a
  3272 warning/error of "Legacy feature: ...", depending on the state of the
  3273 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3274 legacy features will disappear eventually.
  3275 
  3276 * Theory syntax: the header format ``theory A = B + C:'' has been
  3277 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3278 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3279 
  3280 * Theory syntax: the old non-Isar theory file format has been
  3281 discontinued altogether.  Note that ML proof scripts may still be used
  3282 with Isar theories; migration is usually quite simple with the ML
  3283 function use_legacy_bindings.  INCOMPATIBILITY.
  3284 
  3285 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3286 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3287 quotes.
  3288 
  3289 * Theory loader: be more serious about observing the static theory
  3290 header specifications (including optional directories), but not the
  3291 accidental file locations of previously successful loads.  The strict
  3292 update policy of former update_thy is now already performed by
  3293 use_thy, so the former has been removed; use_thys updates several
  3294 theories simultaneously, just as 'imports' within a theory header
  3295 specification, but without merging the results.  Potential
  3296 INCOMPATIBILITY: may need to refine theory headers and commands
  3297 ROOT.ML which depend on load order.
  3298 
  3299 * Theory loader: optional support for content-based file
  3300 identification, instead of the traditional scheme of full physical
  3301 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3302 (cf. the system manual).  The new scheme allows to work with
  3303 non-finished theories in persistent session images, such that source
  3304 files may be moved later on without requiring reloads.
  3305 
  3306 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3307 file (with the same base name as the theory) are considered a legacy
  3308 feature, which will disappear eventually. Even now, the theory loader
  3309 no longer maintains dependencies on such files.
  3310 
  3311 * Syntax: the scope for resolving ambiguities via type-inference is
  3312 now limited to individual terms, instead of whole simultaneous
  3313 specifications as before. This greatly reduces the complexity of the
  3314 syntax module and improves flexibility by separating parsing and
  3315 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3316 'fixes' etc.) are required in rare situations.
  3317 
  3318 * Syntax: constants introduced by new-style packages ('definition',
  3319 'abbreviation' etc.) are passed through the syntax module in
  3320 ``authentic mode''. This means that associated mixfix annotations
  3321 really stick to such constants, independently of potential name space
  3322 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3323 trees are represented slightly differently, may need to adapt syntax
  3324 translations accordingly. Use CONST marker in 'translations' and
  3325 @{const_syntax} antiquotation in 'parse_translation' etc.
  3326 
  3327 * Legacy goal package: reduced interface to the bare minimum required
  3328 to keep existing proof scripts running.  Most other user-level
  3329 functions are now part of the OldGoals structure, which is *not* open
  3330 by default (consider isatool expandshort before open OldGoals).
  3331 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3332 these tend to cause confusion about the actual goal (!) context being
  3333 used here, which is not necessarily the same as the_context().
  3334 
  3335 * Command 'find_theorems': supports "*" wild-card in "name:"
  3336 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3337 support a specific search form (see ProofGeneral/CHANGES).
  3338 
  3339 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3340 by default, which means that "prems" (and also "fixed variables") are
  3341 suppressed from proof state output.  Note that the ProofGeneral
  3342 settings mechanism allows to change and save options persistently, but
  3343 older versions of Isabelle will fail to start up if a negative prems
  3344 limit is imposed.
  3345 
  3346 * Local theory targets may be specified by non-nested blocks of
  3347 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3348 contain definitions, theorems etc., including any derived mechanism
  3349 that has been implemented on top of these primitives.  This concept
  3350 generalizes the existing ``theorem (in ...)'' towards more versatility
  3351 and scalability.
  3352 
  3353 * Proof General interface: proper undo of final 'end' command;
  3354 discontinued Isabelle/classic mode (ML proof scripts).
  3355 
  3356 
  3357 *** Document preparation ***
  3358 
  3359 * Added antiquotation @{theory name} which prints the given name,
  3360 after checking that it refers to a valid ancestor theory in the
  3361 current context.
  3362 
  3363 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3364 check the given source text as ML type/structure, printing verbatim.
  3365 
  3366 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3367 "c args == rhs" given in the current context.  (Any number of
  3368 arguments may be given on the LHS.)
  3369 
  3370 
  3371 *** Pure ***
  3372 
  3373 * The 'class' package offers a combination of axclass and locale to
  3374 achieve Haskell-like type classes in Isabelle.  Definitions and
  3375 theorems within a class context produce both relative results (with
  3376 implicit parameters according to the locale context), and polymorphic
  3377 constants with qualified polymorphism (according to the class
  3378 context).  Within the body context of a 'class' target, a separate
  3379 syntax layer ("user space type system") takes care of converting
  3380 between global polymorphic consts and internal locale representation.
  3381 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3382 "isatool doc classes" provides a tutorial.
  3383 
  3384 * Generic code generator framework allows to generate executable
  3385 code for ML and Haskell (including Isabelle classes).  A short usage
  3386 sketch:
  3387 
  3388     internal compilation:
  3389         export_code <list of constants (term syntax)> in SML
  3390     writing SML code to a file:
  3391         export_code <list of constants (term syntax)> in SML <filename>
  3392     writing OCaml code to a file:
  3393         export_code <list of constants (term syntax)> in OCaml <filename>
  3394     writing Haskell code to a bunch of files:
  3395         export_code <list of constants (term syntax)> in Haskell <filename>
  3396 
  3397     evaluating closed propositions to True/False using code generation:
  3398         method ``eval''
  3399 
  3400 Reasonable default setup of framework in HOL.
  3401 
  3402 Theorem attributs for selecting and transforming function equations theorems:
  3403 
  3404     [code fun]:        select a theorem as function equation for a specific constant
  3405     [code fun del]:    deselect a theorem as function equation for a specific constant
  3406     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3407     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3408 
  3409 User-defined serializations (target in {SML, OCaml, Haskell}):
  3410 
  3411     code_const <and-list of constants (term syntax)>
  3412       {(target) <and-list of const target syntax>}+
  3413 
  3414     code_type <and-list of type constructors>
  3415       {(target) <and-list of type target syntax>}+
  3416 
  3417     code_instance <and-list of instances>
  3418       {(target)}+
  3419         where instance ::= <type constructor> :: <class>
  3420 
  3421     code_class <and_list of classes>
  3422       {(target) <and-list of class target syntax>}+
  3423         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3424 
  3425 code_instance and code_class only are effective to target Haskell.
  3426 
  3427 For example usage see src/HOL/ex/Codegenerator.thy and
  3428 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3429 generation from Isabelle/HOL theories is available via "isatool doc
  3430 codegen".
  3431 
  3432 * Code generator: consts in 'consts_code' Isar commands are now
  3433 referred to by usual term syntax (including optional type
  3434 annotations).
  3435 
  3436 * Command 'no_translations' removes translation rules from theory
  3437 syntax.
  3438 
  3439 * Overloaded definitions are now actually checked for acyclic
  3440 dependencies.  The overloading scheme is slightly more general than
  3441 that of Haskell98, although Isabelle does not demand an exact
  3442 correspondence to type class and instance declarations.
  3443 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3444 exotic versions of overloading -- at the discretion of the user!
  3445 
  3446 Polymorphic constants are represented via type arguments, i.e. the
  3447 instantiation that matches an instance against the most general
  3448 declaration given in the signature.  For example, with the declaration
  3449 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3450 as c(nat).  Overloading is essentially simultaneous structural
  3451 recursion over such type arguments.  Incomplete specification patterns
  3452 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3453 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3454 Command 'print_theory' outputs the normalized system of recursive
  3455 equations, see section "definitions".
  3456 
  3457 * Configuration options are maintained within the theory or proof
  3458 context (with name and type bool/int/string), providing a very simple
  3459 interface to a poor-man's version of general context data.  Tools may
  3460 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3461 these values using Config.get etc.  Users may change options via an
  3462 associated attribute of the same name.  This form of context
  3463 declaration works particularly well with commands 'declare' or
  3464 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3465 very easy to avoid global references, which would not observe Isar
  3466 toplevel undo/redo and fail to work with multithreading.
  3467 
  3468 Various global ML references of Pure and HOL have been turned into
  3469 configuration options:
  3470 
  3471   Unify.search_bound		unify_search_bound
  3472   Unify.trace_bound		unify_trace_bound
  3473   Unify.trace_simp		unify_trace_simp
  3474   Unify.trace_types		unify_trace_types
  3475   Simplifier.simp_depth_limit	simp_depth_limit
  3476   Blast.depth_limit		blast_depth_limit
  3477   DatatypeProp.dtK		datatype_distinctness_limit
  3478   fast_arith_neq_limit  	fast_arith_neq_limit
  3479   fast_arith_split_limit	fast_arith_split_limit
  3480 
  3481 * Named collections of theorems may be easily installed as context
  3482 data using the functor NamedThmsFun (see also
  3483 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3484 attributes; there is also a toplevel print command.  This facility is
  3485 just a common case of general context data, which is the preferred way
  3486 for anything more complex than just a list of facts in canonical
  3487 order.
  3488 
  3489 * Isar: command 'declaration' augments a local theory by generic
  3490 declaration functions written in ML.  This enables arbitrary content
  3491 being added to the context, depending on a morphism that tells the
  3492 difference of the original declaration context wrt. the application
  3493 context encountered later on.
  3494 
  3495 * Isar: proper interfaces for simplification procedures.  Command
  3496 'simproc_setup' declares named simprocs (with match patterns, and body
  3497 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3498 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3499 
  3500 * Isar: an extra pair of brackets around attribute declarations
  3501 abbreviates a theorem reference involving an internal dummy fact,
  3502 which will be ignored later --- only the effect of the attribute on
  3503 the background context will persist.  This form of in-place
  3504 declarations is particularly useful with commands like 'declare' and
  3505 'using', for example ``have A using [[simproc a]] by simp''.
  3506 
  3507 * Isar: method "assumption" (and implicit closing of subproofs) now
  3508 takes simple non-atomic goal assumptions into account: after applying
  3509 an assumption as a rule the resulting subgoals are solved by atomic
  3510 assumption steps.  This is particularly useful to finish 'obtain'
  3511 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3512 without referring to the original premise "!!x. P x ==> thesis" in the
  3513 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3514 more permissive.
  3515 
  3516 * Isar: implicit use of prems from the Isar proof context is
  3517 considered a legacy feature.  Common applications like ``have A .''
  3518 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3519 referencing facts explicitly here improves readability and
  3520 maintainability of proof texts.
  3521 
  3522 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3523 the obtained context from the course of reasoning!  For example:
  3524 
  3525   assume "EX x y. A x & B y"   -- "any previous fact"
  3526   then guess x and y by clarify
  3527 
  3528 This technique is potentially adventurous, depending on the facts and
  3529 proof tools being involved here.
  3530 
  3531 * Isar: known facts from the proof context may be specified as literal
  3532 propositions, using ASCII back-quote syntax.  This works wherever
  3533 named facts used to be allowed so far, in proof commands, proof
  3534 methods, attributes etc.  Literal facts are retrieved from the context
  3535 according to unification of type and term parameters.  For example,
  3536 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3537 theorems in the current context, then these are valid literal facts:
  3538 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3539 
  3540 There is also a proof method "fact" which does the same composition
  3541 for explicit goal states, e.g. the following proof texts coincide with
  3542 certain special cases of literal facts:
  3543 
  3544   have "A" by fact                 ==  note `A`
  3545   have "A ==> B" by fact           ==  note `A ==> B`
  3546   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3547   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3548 
  3549 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3550 outer syntax.  Thus symbolic identifiers may be used without
  3551 additional white space in declarations like this: ``assume *: A''.
  3552 
  3553 * Isar: 'print_facts' prints all local facts of the current context,
  3554 both named and unnamed ones.
  3555 
  3556 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3557 
  3558   def x == "t" and y == "u"
  3559 
  3560 * Isar: added command 'unfolding', which is structurally similar to
  3561 'using', but affects both the goal state and facts by unfolding given
  3562 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3563 'unfolded' attribute may be replaced by first-class proof text.
  3564 
  3565 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3566 and command 'unfolding' now all support object-level equalities
  3567 (potentially conditional).  The underlying notion of rewrite rule is
  3568 analogous to the 'rule_format' attribute, but *not* that of the
  3569 Simplifier (which is usually more generous).
  3570 
  3571 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3572 premises of a theorem by n. Useful in conjunction with drule.
  3573 
  3574 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3575 method expression within a sandbox consisting of the first N
  3576 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3577 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3578 simplifies all new goals that emerge from applying rule foo to the
  3579 originally first one.
  3580 
  3581 * Isar: schematic goals are no longer restricted to higher-order
  3582 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3583 expected.
  3584 
  3585 * Isar: the conclusion of a long theorem statement is now either
  3586 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3587 (essentially a disjunction of cases with local parameters and
  3588 assumptions).  The latter allows to express general elimination rules
  3589 adequately; in this notation common elimination rules look like this:
  3590 
  3591   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3592     assumes "EX x. P x"
  3593     obtains x where "P x"
  3594 
  3595   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3596     assumes "A & B"
  3597     obtains A and B
  3598 
  3599   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3600     assumes "A | B"
  3601     obtains
  3602       A
  3603     | B
  3604 
  3605 The subsequent classical rules even refer to the formal "thesis"
  3606 explicitly:
  3607 
  3608   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3609     obtains "~ thesis"
  3610 
  3611   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3612     obtains "thesis ==> something"
  3613 
  3614 The actual proof of an 'obtains' statement is analogous to that of the
  3615 Isar proof element 'obtain', only that there may be several cases.
  3616 Optional case names may be specified in parentheses; these will be
  3617 available both in the present proof and as annotations in the
  3618 resulting rule, for later use with the 'cases' method (cf. attribute
  3619 case_names).
  3620 
  3621 * Isar: the assumptions of a long theorem statement are available as
  3622 "assms" fact in the proof context.  This is more appropriate than the
  3623 (historical) "prems", which refers to all assumptions of the current
  3624 context, including those from the target locale, proof body etc.
  3625 
  3626 * Isar: 'print_statement' prints theorems from the current theory or
  3627 proof context in long statement form, according to the syntax of a
  3628 top-level lemma.
  3629 
  3630 * Isar: 'obtain' takes an optional case name for the local context
  3631 introduction rule (default "that").
  3632 
  3633 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3634 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3635 to occur.
  3636 
  3637 * Pure: syntax "CONST name" produces a fully internalized constant
  3638 according to the current context.  This is particularly useful for
  3639 syntax translations that should refer to internal constant
  3640 representations independently of name spaces.
  3641 
  3642 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3643 instead of "FOO ". This allows multiple binder declarations to coexist
  3644 in the same context.  INCOMPATIBILITY.
  3645 
  3646 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3647 primitive that also works in a locale context (both for constants and
  3648 fixed variables). Type declaration and internal syntactic representation
  3649 of given constants retrieved from the context. Likewise, the
  3650 'no_notation' command allows to remove given syntax annotations from the
  3651 current context.
  3652 
  3653 * Isar/locales: new derived specification elements 'axiomatization',
  3654 'definition', 'abbreviation', which support type-inference, admit
  3655 object-level specifications (equality, equivalence).  See also the
  3656 isar-ref manual.  Examples:
  3657 
  3658   axiomatization
  3659     eq  (infix "===" 50) where
  3660     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3661 
  3662   definition "f x y = x + y + 1"
  3663   definition g where "g x = f x x"
  3664 
  3665   abbreviation
  3666     neq  (infix "=!=" 50) where
  3667     "x =!= y == ~ (x === y)"
  3668 
  3669 These specifications may be also used in a locale context.  Then the
  3670 constants being introduced depend on certain fixed parameters, and the
  3671 constant name is qualified by the locale base name.  An internal
  3672 abbreviation takes care for convenient input and output, making the
  3673 parameters implicit and using the original short name.  See also
  3674 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3675 entities from a monomorphic theory.
  3676 
  3677 Presently, abbreviations are only available 'in' a target locale, but
  3678 not inherited by general import expressions.  Also note that
  3679 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3680 'translations' in common applications.  The "no_abbrevs" print mode
  3681 prevents folding of abbreviations in term output.
  3682 
  3683 Concrete syntax is attached to specified constants in internal form,
  3684 independently of name spaces.  The parse tree representation is
  3685 slightly different -- use 'notation' instead of raw 'syntax', and
  3686 'translations' with explicit "CONST" markup to accommodate this.
  3687 
  3688 * Pure/Isar: unified syntax for new-style specification mechanisms
  3689 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3690 full type inference and dummy patterns ("_").  For example:
  3691 
  3692   definition "K x _ = x"
  3693 
  3694   inductive conj for A B
  3695   where "A ==> B ==> conj A B"
  3696 
  3697 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3698 the current context.  Print mode "no_abbrevs" prevents inversion of
  3699 abbreviations on output.
  3700 
  3701 * Isar/locales: improved parameter handling: use of locales "var" and
  3702 "struct" no longer necessary; - parameter renamings are no longer
  3703 required to be injective.  For example, this allows to define
  3704 endomorphisms as locale endom = homom mult mult h.
  3705 
  3706 * Isar/locales: changed the way locales with predicates are defined.
  3707 Instead of accumulating the specification, the imported expression is
  3708 now an interpretation.  INCOMPATIBILITY: different normal form of
  3709 locale expressions.  In particular, in interpretations of locales with
  3710 predicates, goals repesenting already interpreted fragments are not
  3711 removed automatically.  Use methods `intro_locales' and
  3712 `unfold_locales'; see below.
  3713 
  3714 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3715 provide backward reasoning on locales predicates.  The methods are
  3716 aware of interpretations and discharge corresponding goals.
  3717 `intro_locales' is less aggressive then `unfold_locales' and does not
  3718 unfold predicates to assumptions.
  3719 
  3720 * Isar/locales: the order in which locale fragments are accumulated
  3721 has changed.  This enables to override declarations from fragments due
  3722 to interpretations -- for example, unwanted simp rules.
  3723 
  3724 * Isar/locales: interpretation in theories and proof contexts has been
  3725 extended.  One may now specify (and prove) equations, which are
  3726 unfolded in interpreted theorems.  This is useful for replacing
  3727 defined concepts (constants depending on locale parameters) by
  3728 concepts already existing in the target context.  Example:
  3729 
  3730   interpretation partial_order ["op <= :: [int, int] => bool"]
  3731     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3732 
  3733 Typically, the constant `partial_order.less' is created by a
  3734 definition specification element in the context of locale
  3735 partial_order.
  3736 
  3737 * Method "induct": improved internal context management to support
  3738 local fixes and defines on-the-fly. Thus explicit meta-level
  3739 connectives !!  and ==> are rarely required anymore in inductive goals
  3740 (using object-logic connectives for this purpose has been long
  3741 obsolete anyway). Common proof patterns are explained in
  3742 src/HOL/Induct/Common_Patterns.thy, see also
  3743 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3744 examples.
  3745 
  3746 * Method "induct": improved handling of simultaneous goals. Instead of
  3747 introducing object-level conjunction, the statement is now split into
  3748 several conclusions, while the corresponding symbolic cases are nested
  3749 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3750 see src/HOL/Induct/Common_Patterns.thy, for example.
  3751 
  3752 * Method "induct": mutual induction rules are now specified as a list
  3753 of rule sharing the same induction cases. HOL packages usually provide
  3754 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3755 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3756 mutual induction rules differently, i.e. like this:
  3757 
  3758   (induct rule: foo_bar.inducts)
  3759   (induct set: foo bar)
  3760   (induct pred: foo bar)
  3761   (induct type: foo bar)
  3762 
  3763 The ML function ProjectRule.projections turns old-style rules into the
  3764 new format.
  3765 
  3766 * Method "coinduct": dual of induction, see
  3767 src/HOL/Library/Coinductive_List.thy for various examples.
  3768 
  3769 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3770 considered a legacy feature.
  3771 
  3772 * Attribute "symmetric" produces result with standardized schematic
  3773 variables (index 0).  Potential INCOMPATIBILITY.
  3774 
  3775 * Simplifier: by default the simplifier trace only shows top level
  3776 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3777 default. Thus there is less danger of being flooded by the trace. The
  3778 trace indicates where parts have been suppressed.
  3779   
  3780 * Provers/classical: removed obsolete classical version of elim_format
  3781 attribute; classical elim/dest rules are now treated uniformly when
  3782 manipulating the claset.
  3783 
  3784 * Provers/classical: stricter checks to ensure that supplied intro,
  3785 dest and elim rules are well-formed; dest and elim rules must have at
  3786 least one premise.
  3787 
  3788 * Provers/classical: attributes dest/elim/intro take an optional
  3789 weight argument for the rule (just as the Pure versions).  Weights are
  3790 ignored by automated tools, but determine the search order of single
  3791 rule steps.
  3792 
  3793 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3794 where the body does not mention the bound variable.  Note that dummy
  3795 patterns implicitly depend on their context of bounds, which makes
  3796 "{_. _}" match any set comprehension as expected.  Potential
  3797 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3798 constant "_idtdummy" in the binding position.
  3799 
  3800 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3801 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3802 for example "A -> B" => "Pi A (%_. B)".
  3803 
  3804 * Pure: 'class_deps' command visualizes the subclass relation, using
  3805 the graph browser tool.
  3806 
  3807 * Pure: 'print_theory' now suppresses certain internal declarations by
  3808 default; use '!' option for full details.
  3809 
  3810 
  3811 *** HOL ***
  3812 
  3813 * Method "metis" proves goals by applying the Metis general-purpose
  3814 resolution prover (see also http://gilith.com/software/metis/).
  3815 Examples are in the directory MetisExamples.  WARNING: the
  3816 Isabelle/HOL-Metis integration does not yet work properly with
  3817 multi-threading.
  3818   
  3819 * Command 'sledgehammer' invokes external automatic theorem provers as
  3820 background processes.  It generates calls to the "metis" method if
  3821 successful. These can be pasted into the proof.  Users do not have to
  3822 wait for the automatic provers to return.  WARNING: does not really
  3823 work with multi-threading.
  3824 
  3825 * New "auto_quickcheck" feature tests outermost goal statements for
  3826 potential counter-examples.  Controlled by ML references
  3827 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3828 5000 milliseconds).  Fails silently if statements is outside of
  3829 executable fragment, or any other codgenerator problem occurs.
  3830 
  3831 * New constant "undefined" with axiom "undefined x = undefined".
  3832 
  3833 * Added class "HOL.eq", allowing for code generation with polymorphic
  3834 equality.
  3835 
  3836 * Some renaming of class constants due to canonical name prefixing in
  3837 the new 'class' package:
  3838 
  3839     HOL.abs ~> HOL.abs_class.abs
  3840     HOL.divide ~> HOL.divide_class.divide
  3841     0 ~> HOL.zero_class.zero
  3842     1 ~> HOL.one_class.one
  3843     op + ~> HOL.plus_class.plus
  3844     op - ~> HOL.minus_class.minus
  3845     uminus ~> HOL.minus_class.uminus
  3846     op * ~> HOL.times_class.times
  3847     op < ~> HOL.ord_class.less
  3848     op <= > HOL.ord_class.less_eq
  3849     Nat.power ~> Power.power_class.power
  3850     Nat.size ~> Nat.size_class.size
  3851     Numeral.number_of ~> Numeral.number_class.number_of
  3852     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3853     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3854     Orderings.min ~> Orderings.ord_class.min
  3855     Orderings.max ~> Orderings.ord_class.max
  3856     Divides.op div ~> Divides.div_class.div
  3857     Divides.op mod ~> Divides.div_class.mod
  3858     Divides.op dvd ~> Divides.div_class.dvd
  3859 
  3860 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3861 
  3862 a) User-defined constants using any of the names "plus", "minus",
  3863 "times", "less" or "less_eq". The standard syntax translations for
  3864 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3865 names.
  3866 
  3867 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3868 INCOMPATIBILITY: use more specific names.
  3869 
  3870 c) Permutative equations (e.g. "a + b = b + a")
  3871 Since the change of names also changes the order of terms, permutative
  3872 rewrite rules may get applied in a different order. Experience shows
  3873 that this is rarely the case (only two adaptions in the whole Isabelle
  3874 distribution).  INCOMPATIBILITY: rewrite proofs
  3875 
  3876 d) ML code directly refering to constant names
  3877 This in general only affects hand-written proof tactics, simprocs and
  3878 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3879 Consider using @{const_name} antiquotation.
  3880 
  3881 * New class "default" with associated constant "default".
  3882 
  3883 * Function "sgn" is now overloaded and available on int, real, complex
  3884 (and other numeric types), using class "sgn".  Two possible defs of
  3885 sgn are given as equational assumptions in the classes sgn_if and
  3886 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3887 INCOMPATIBILITY.
  3888 
  3889 * Locale "partial_order" now unified with class "order" (cf. theory
  3890 Orderings), added parameter "less".  INCOMPATIBILITY.
  3891 
  3892 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3893 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3894 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3895 
  3896 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3897 changed order of proof goals in instance proofs.
  3898 
  3899 * The transitivity reasoner for partial and linear orders is set up
  3900 for classes "order" and "linorder".  Instances of the reasoner are available
  3901 in all contexts importing or interpreting the corresponding locales.
  3902 Method "order" invokes the reasoner separately; the reasoner
  3903 is also integrated with the Simplifier as a solver.  Diagnostic
  3904 command 'print_orders' shows the available instances of the reasoner
  3905 in the current context.
  3906 
  3907 * Localized monotonicity predicate in theory "Orderings"; integrated
  3908 lemmas max_of_mono and min_of_mono with this predicate.
  3909 INCOMPATIBILITY.
  3910 
  3911 * Formulation of theorem "dense" changed slightly due to integration
  3912 with new class dense_linear_order.
  3913 
  3914 * Uniform lattice theory development in HOL.
  3915 
  3916     constants "meet" and "join" now named "inf" and "sup"
  3917     constant "Meet" now named "Inf"
  3918 
  3919     classes "meet_semilorder" and "join_semilorder" now named
  3920       "lower_semilattice" and "upper_semilattice"
  3921     class "lorder" now named "lattice"
  3922     class "comp_lat" now named "complete_lattice"
  3923 
  3924     Instantiation of lattice classes allows explicit definitions
  3925     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3926 
  3927   INCOMPATIBILITY.  Theorem renames:
  3928 
  3929     meet_left_le            ~> inf_le1
  3930     meet_right_le           ~> inf_le2
  3931     join_left_le            ~> sup_ge1
  3932     join_right_le           ~> sup_ge2
  3933     meet_join_le            ~> inf_sup_ord
  3934     le_meetI                ~> le_infI
  3935     join_leI                ~> le_supI
  3936     le_meet                 ~> le_inf_iff
  3937     le_join                 ~> ge_sup_conv
  3938     meet_idempotent         ~> inf_idem
  3939     join_idempotent         ~> sup_idem
  3940     meet_comm               ~> inf_commute
  3941     join_comm               ~> sup_commute
  3942     meet_leI1               ~> le_infI1
  3943     meet_leI2               ~> le_infI2
  3944     le_joinI1               ~> le_supI1
  3945     le_joinI2               ~> le_supI2
  3946     meet_assoc              ~> inf_assoc
  3947     join_assoc              ~> sup_assoc
  3948     meet_left_comm          ~> inf_left_commute
  3949     meet_left_idempotent    ~> inf_left_idem
  3950     join_left_comm          ~> sup_left_commute
  3951     join_left_idempotent    ~> sup_left_idem
  3952     meet_aci                ~> inf_aci
  3953     join_aci                ~> sup_aci
  3954     le_def_meet             ~> le_iff_inf
  3955     le_def_join             ~> le_iff_sup
  3956     join_absorp2            ~> sup_absorb2
  3957     join_absorp1            ~> sup_absorb1
  3958     meet_absorp1            ~> inf_absorb1
  3959     meet_absorp2            ~> inf_absorb2
  3960     meet_join_absorp        ~> inf_sup_absorb
  3961     join_meet_absorp        ~> sup_inf_absorb
  3962     distrib_join_le         ~> distrib_sup_le
  3963     distrib_meet_le         ~> distrib_inf_le
  3964 
  3965     add_meet_distrib_left   ~> add_inf_distrib_left
  3966     add_join_distrib_left   ~> add_sup_distrib_left
  3967     is_join_neg_meet        ~> is_join_neg_inf
  3968     is_meet_neg_join        ~> is_meet_neg_sup
  3969     add_meet_distrib_right  ~> add_inf_distrib_right
  3970     add_join_distrib_right  ~> add_sup_distrib_right
  3971     add_meet_join_distribs  ~> add_sup_inf_distribs
  3972     join_eq_neg_meet        ~> sup_eq_neg_inf
  3973     meet_eq_neg_join        ~> inf_eq_neg_sup
  3974     add_eq_meet_join        ~> add_eq_inf_sup
  3975     meet_0_imp_0            ~> inf_0_imp_0
  3976     join_0_imp_0            ~> sup_0_imp_0
  3977     meet_0_eq_0             ~> inf_0_eq_0
  3978     join_0_eq_0             ~> sup_0_eq_0
  3979     neg_meet_eq_join        ~> neg_inf_eq_sup
  3980     neg_join_eq_meet        ~> neg_sup_eq_inf
  3981     join_eq_if              ~> sup_eq_if
  3982 
  3983     mono_meet               ~> mono_inf
  3984     mono_join               ~> mono_sup
  3985     meet_bool_eq            ~> inf_bool_eq
  3986     join_bool_eq            ~> sup_bool_eq
  3987     meet_fun_eq             ~> inf_fun_eq
  3988     join_fun_eq             ~> sup_fun_eq
  3989     meet_set_eq             ~> inf_set_eq
  3990     join_set_eq             ~> sup_set_eq
  3991     meet1_iff               ~> inf1_iff
  3992     meet2_iff               ~> inf2_iff
  3993     meet1I                  ~> inf1I
  3994     meet2I                  ~> inf2I
  3995     meet1D1                 ~> inf1D1
  3996     meet2D1                 ~> inf2D1
  3997     meet1D2                 ~> inf1D2
  3998     meet2D2                 ~> inf2D2
  3999     meet1E                  ~> inf1E
  4000     meet2E                  ~> inf2E
  4001     join1_iff               ~> sup1_iff
  4002     join2_iff               ~> sup2_iff
  4003     join1I1                 ~> sup1I1
  4004     join2I1                 ~> sup2I1
  4005     join1I1                 ~> sup1I1
  4006     join2I2                 ~> sup1I2
  4007     join1CI                 ~> sup1CI
  4008     join2CI                 ~> sup2CI
  4009     join1E                  ~> sup1E
  4010     join2E                  ~> sup2E
  4011 
  4012     is_meet_Meet            ~> is_meet_Inf
  4013     Meet_bool_def           ~> Inf_bool_def
  4014     Meet_fun_def            ~> Inf_fun_def
  4015     Meet_greatest           ~> Inf_greatest
  4016     Meet_lower              ~> Inf_lower
  4017     Meet_set_def            ~> Inf_set_def
  4018 
  4019     Sup_def                 ~> Sup_Inf
  4020     Sup_bool_eq             ~> Sup_bool_def
  4021     Sup_fun_eq              ~> Sup_fun_def
  4022     Sup_set_eq              ~> Sup_set_def
  4023 
  4024     listsp_meetI            ~> listsp_infI
  4025     listsp_meet_eq          ~> listsp_inf_eq
  4026 
  4027     meet_min                ~> inf_min
  4028     join_max                ~> sup_max
  4029 
  4030 * Added syntactic class "size"; overloaded constant "size" now has
  4031 type "'a::size ==> bool"
  4032 
  4033 * Internal reorganisation of `size' of datatypes: size theorems
  4034 "foo.size" are no longer subsumed by "foo.simps" (but are still
  4035 simplification rules by default!); theorems "prod.size" now named
  4036 "*.size".
  4037 
  4038 * Class "div" now inherits from class "times" rather than "type".
  4039 INCOMPATIBILITY.
  4040 
  4041 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  4042 Linorder etc.  have disappeared; operations defined in terms of
  4043 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  4044 
  4045 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  4046 
  4047 * HOL-Word: New extensive library and type for generic, fixed size
  4048 machine words, with arithemtic, bit-wise, shifting and rotating
  4049 operations, reflection into int, nat, and bool lists, automation for
  4050 linear arithmetic (by automatic reflection into nat or int), including
  4051 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  4052 arithmetic type classes, supporting automatic simplification of
  4053 numerals on all operations.
  4054 
  4055 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  4056 
  4057 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  4058 
  4059 * Code generator library theories:
  4060   - Code_Integer represents HOL integers by big integer literals in target
  4061     languages.
  4062   - Code_Char represents HOL characters by character literals in target
  4063     languages.
  4064   - Code_Char_chr like Code_Char, but also offers treatment of character
  4065     codes; includes Code_Integer.
  4066   - Executable_Set allows to generate code for finite sets using lists.
  4067   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  4068     denominator).
  4069   - Executable_Real implements a subset of real numbers, namly those
  4070     representable by rational numbers.
  4071   - Efficient_Nat implements natural numbers by integers, which in general will
  4072     result in higher efficency; pattern matching with 0/Suc is eliminated;
  4073     includes Code_Integer.
  4074   - Code_Index provides an additional datatype index which is mapped to
  4075     target-language built-in integers.
  4076   - Code_Message provides an additional datatype message_string which is isomorphic to
  4077     strings; messages are mapped to target-language strings.
  4078 
  4079 * New package for inductive predicates
  4080 
  4081   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  4082 
  4083     inductive
  4084       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4085       for z_1 :: U_1 and ... and z_n :: U_m
  4086     where
  4087       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4088     | ...
  4089 
  4090   with full support for type-inference, rather than
  4091 
  4092     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4093 
  4094     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4095     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4096 
  4097     inductive "s z_1 ... z_m"
  4098     intros
  4099       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4100       ...
  4101 
  4102   For backward compatibility, there is a wrapper allowing inductive
  4103   sets to be defined with the new package via
  4104 
  4105     inductive_set
  4106       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4107       for z_1 :: U_1 and ... and z_n :: U_m
  4108     where
  4109       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4110     | ...
  4111 
  4112   or
  4113 
  4114     inductive_set
  4115       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4116       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4117       for z_1 :: U_1 and ... and z_n :: U_m
  4118     where
  4119       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4120     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4121     | ...
  4122 
  4123   if the additional syntax "p ..." is required.
  4124 
  4125   Numerous examples can be found in the subdirectories src/HOL/Auth,
  4126   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  4127 
  4128   INCOMPATIBILITIES:
  4129 
  4130   - Since declaration and definition of inductive sets or predicates
  4131     is no longer separated, abbreviations involving the newly
  4132     introduced sets or predicates must be specified together with the
  4133     introduction rules after the 'where' keyword (see above), rather
  4134     than before the actual inductive definition.
  4135 
  4136   - The variables in induction and elimination rules are now
  4137     quantified in the order of their occurrence in the introduction
  4138     rules, rather than in alphabetical order. Since this may break
  4139     some proofs, these proofs either have to be repaired, e.g. by
  4140     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  4141     statements of the form
  4142 
  4143       case (rule_i a_i_1 ... a_i_{k_i})
  4144 
  4145     or the old order of quantification has to be restored by explicitly adding
  4146     meta-level quantifiers in the introduction rules, i.e.
  4147 
  4148       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  4149 
  4150   - The format of the elimination rules is now
  4151 
  4152       p z_1 ... z_m x_1 ... x_n ==>
  4153         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4154         ==> ... ==> P
  4155 
  4156     for predicates and
  4157 
  4158       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4159         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4160         ==> ... ==> P
  4161 
  4162     for sets rather than
  4163 
  4164       x : s z_1 ... z_m ==>
  4165         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4166         ==> ... ==> P
  4167 
  4168     This may require terms in goals to be expanded to n-tuples
  4169     (e.g. using case_tac or simplification with the split_paired_all
  4170     rule) before the above elimination rule is applicable.
  4171 
  4172   - The elimination or case analysis rules for (mutually) inductive
  4173     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4174     list of rules "p_1_..._p_k.elims" is no longer available.
  4175 
  4176 * New package "function"/"fun" for general recursive functions,
  4177 supporting mutual and nested recursion, definitions in local contexts,
  4178 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4179 for small examples, and the separate tutorial on the function
  4180 package. The old recdef "package" is still available as before, but
  4181 users are encouraged to use the new package.
  4182 
  4183 * Method "lexicographic_order" automatically synthesizes termination
  4184 relations as lexicographic combinations of size measures. 
  4185 
  4186 * Case-expressions allow arbitrary constructor-patterns (including
  4187 "_") and take their order into account, like in functional
  4188 programming.  Internally, this is translated into nested
  4189 case-expressions; missing cases are added and mapped to the predefined
  4190 constant "undefined". In complicated cases printing may no longer show
  4191 the original input but the internal form. Lambda-abstractions allow
  4192 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4193 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4194 variable.
  4195 
  4196 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4197 is an abbreviation for "of_nat :: nat => int". The simplification
  4198 rules for "of_nat" have been changed to work like "int" did
  4199 previously.  Potential INCOMPATIBILITY:
  4200   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4201   - of_nat_diff and of_nat_mult are no longer default simp rules
  4202 
  4203 * Method "algebra" solves polynomial equations over (semi)rings using
  4204 Groebner bases. The (semi)ring structure is defined by locales and the
  4205 tool setup depends on that generic context. Installing the method for
  4206 a specific type involves instantiating the locale and possibly adding
  4207 declarations for computation on the coefficients.  The method is
  4208 already instantiated for natural numbers and for the axiomatic class
  4209 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4210 CALCULEMUS 2007 for the general principles underlying this
  4211 architecture of context-aware proof-tools.
  4212 
  4213 * Method "ferrack" implements quantifier elimination over
  4214 special-purpose dense linear orders using locales (analogous to
  4215 "algebra"). The method is already installed for class
  4216 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4217 rat, etc.
  4218 
  4219 * Former constant "List.op @" now named "List.append".  Use ML
  4220 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4221 circumvent possible incompatibilities when working on ML level.
  4222 
  4223 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4224 
  4225 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4226 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4227 
  4228 * New syntax for Haskell-like list comprehension (input only), eg.
  4229 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4230 
  4231 * The special syntax for function "filter" has changed from [x :
  4232 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4233 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4234 
  4235 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4236 defined on nat only, as an abbreviation for [a..<Suc b]
  4237 INCOMPATIBILITY.
  4238 
  4239 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4240 
  4241 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4242 
  4243 * New lemma collection field_simps (an extension of ring_simps) for
  4244 manipulating (in)equations involving division. Multiplies with all
  4245 denominators that can be proved to be non-zero (in equations) or
  4246 positive/negative (in inequations).
  4247 
  4248 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4249 have been improved and renamed to ring_simps, group_simps and
  4250 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4251 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4252 
  4253 * Theory Library/Commutative_Ring: switched from recdef to function
  4254 package; constants add, mul, pow now curried.  Infix syntax for
  4255 algebraic operations.
  4256 
  4257 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4258 INCOMPATIBILITY.
  4259 
  4260 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4261 INCOMPATIBILITY.
  4262 
  4263 * HOL/records: generalised field-update to take a function on the
  4264 field rather than the new value: r(|A := x|) is translated to A_update
  4265 (K x) r The K-combinator that is internally used is called K_record.
  4266 INCOMPATIBILITY: Usage of the plain update functions has to be
  4267 adapted.
  4268  
  4269 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4270 * x = 0, which are required for a semiring.  Richer structures do not
  4271 inherit from semiring_0 anymore, because this property is a theorem
  4272 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4273 there is more to prove, but this is mostly trivial.
  4274 
  4275 * Class "recpower" is generalized to arbitrary monoids, not just
  4276 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4277 commutativity or semiring properties additionally.
  4278 
  4279 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4280 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4281 better use 'abbreviation'.
  4282 
  4283 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4284 
  4285 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4286 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4287 significant changes for setting up numeral syntax for types:
  4288   - New constants Numeral.pred and Numeral.succ instead
  4289       of former Numeral.bin_pred and Numeral.bin_succ.
  4290   - Use integer operations instead of bin_add, bin_mult and so on.
  4291   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4292   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4293 
  4294 See src/HOL/Integ/IntArith.thy for an example setup.
  4295 
  4296 * Command 'normal_form' computes the normal form of a term that may
  4297 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4298 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4299 heavy-duty computations because the functions are compiled to ML
  4300 first.  Correspondingly, a method "normalization" is provided.  See
  4301 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4302 
  4303 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4304 25 like -->); output depends on the "iff" print_mode, the default is
  4305 "A = B" (with priority 50).
  4306 
  4307 * Relations less (<) and less_eq (<=) are also available on type bool.
  4308 Modified syntax to disallow nesting without explicit parentheses,
  4309 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4310 INCOMPATIBILITY.
  4311 
  4312 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4313 
  4314 * Relation composition operator "op O" now has precedence 75 and binds
  4315 stronger than union and intersection. INCOMPATIBILITY.
  4316 
  4317 * The old set interval syntax "{m..n(}" (and relatives) has been
  4318 removed.  Use "{m..<n}" (and relatives) instead.
  4319 
  4320 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4321 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4322 ``declare [[simproc del: neq]]''.
  4323 
  4324 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4325 True/False.
  4326 
  4327 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4328 
  4329 * Theorem setsum_mult renamed to setsum_right_distrib.
  4330 
  4331 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4332 ``rule'' method.
  4333 
  4334 * Reimplemented methods "sat" and "satx", with several improvements:
  4335 goals no longer need to be stated as "<prems> ==> False", equivalences
  4336 (i.e. "=" on type bool) are handled, variable names of the form
  4337 "lit_<n>" are no longer reserved, significant speedup.
  4338 
  4339 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4340 zChaff is still supported as well.
  4341 
  4342 * 'inductive' and 'datatype': provide projections of mutual rules,
  4343 bundled as foo_bar.inducts;
  4344 
  4345 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4346 Library.
  4347 
  4348 * Library: moved theory Accessible_Part to main HOL.
  4349 
  4350 * Library: added theory Coinductive_List of potentially infinite lists
  4351 as greatest fixed-point.
  4352 
  4353 * Library: added theory AssocList which implements (finite) maps as
  4354 association lists.
  4355 
  4356 * Method "evaluation" solves goals (i.e. a boolean expression)
  4357 efficiently by compiling it to ML.  The goal is "proved" (via an
  4358 oracle) if it evaluates to True.
  4359 
  4360 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4361 also when invoked by the simplifier.  This results in the Simplifier
  4362 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4363 Configuration option fast_arith_split_limit=0 recovers the old
  4364 behavior.
  4365 
  4366 * Support for hex (0x20) and binary (0b1001) numerals.
  4367 
  4368 * New method: reify eqs (t), where eqs are equations for an
  4369 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4370 parameter, computes a term s::'b and a list xs::'a list and proves the
  4371 theorem I xs s = t. This is also known as reification or quoting. The
  4372 resulting theorem is applied to the subgoal to substitute t with I xs
  4373 s.  If t is omitted, the subgoal itself is reified.
  4374 
  4375 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4376 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4377 where f is supposed to be a computable function (in the sense of code
  4378 generattion). The method uses reify to compute s and xs as above then
  4379 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4380 r and finally gets the theorem t = r, which is again applied to the
  4381 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4382 
  4383 * Reflection: Automatic reification now handels binding, an example is
  4384 available in src/HOL/ex/ReflectionEx.thy
  4385 
  4386 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4387 command 'statespace' that is similar to 'record', but introduces an
  4388 abstract specification based on the locale infrastructure instead of
  4389 HOL types.  This leads to extra flexibility in composing state spaces,
  4390 in particular multiple inheritance and renaming of components.
  4391 
  4392 
  4393 *** HOL-Complex ***
  4394 
  4395 * Hyperreal: Functions root and sqrt are now defined on negative real
  4396 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4397 Nonnegativity side conditions have been removed from many lemmas, so
  4398 that more subgoals may now be solved by simplification; potential
  4399 INCOMPATIBILITY.
  4400 
  4401 * Real: new type classes formalize real normed vector spaces and
  4402 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4403 and norm :: 'a => real.
  4404 
  4405 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4406 reals into other types. The overloaded constant Reals :: 'a set is now
  4407 defined as range of_real; potential INCOMPATIBILITY.
  4408 
  4409 * Real: proper support for ML code generation, including 'quickcheck'.
  4410 Reals are implemented as arbitrary precision rationals.
  4411 
  4412 * Hyperreal: Several constants that previously worked only for the
  4413 reals have been generalized, so they now work over arbitrary vector
  4414 spaces. Type annotations may need to be added in some cases; potential
  4415 INCOMPATIBILITY.
  4416 
  4417   Infinitesimal  :: ('a::real_normed_vector) star set
  4418   HFinite        :: ('a::real_normed_vector) star set
  4419   HInfinite      :: ('a::real_normed_vector) star set
  4420   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4421   monad          :: ('a::real_normed_vector) star => 'a star set
  4422   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4423   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4424   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4425   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4426   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4427   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4428   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4429   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4430   sgn            :: 'a::real_normed_vector => 'a
  4431   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4432 
  4433 * Complex: Some complex-specific constants are now abbreviations for
  4434 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4435 hnorm.  Other constants have been entirely removed in favor of the
  4436 polymorphic versions (INCOMPATIBILITY):
  4437 
  4438   approx        <-- capprox
  4439   HFinite       <-- CFinite
  4440   HInfinite     <-- CInfinite
  4441   Infinitesimal <-- CInfinitesimal
  4442   monad         <-- cmonad
  4443   galaxy        <-- cgalaxy
  4444   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4445   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4446   (ns)deriv     <-- (ns)cderiv
  4447 
  4448 
  4449 *** HOL-Algebra ***
  4450 
  4451 * Formalisation of ideals and the quotient construction over rings.
  4452 
  4453 * Order and lattice theory no longer based on records.
  4454 INCOMPATIBILITY.
  4455 
  4456 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4457 greatest_closed.  INCOMPATIBILITY.
  4458 
  4459 * Method algebra is now set up via an attribute.  For examples see
  4460 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4461 of algebraic structures.
  4462 
  4463 * Renamed theory CRing to Ring.
  4464 
  4465 
  4466 *** HOL-Nominal ***
  4467 
  4468 * Substantial, yet incomplete support for nominal datatypes (binding
  4469 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4470 src/HOL/Nominal/Examples.  Prospective users should consult
  4471 http://isabelle.in.tum.de/nominal/
  4472 
  4473 
  4474 *** ML ***
  4475 
  4476 * ML basics: just one true type int, which coincides with IntInf.int
  4477 (even on SML/NJ).
  4478 
  4479 * ML within Isar: antiquotations allow to embed statically-checked
  4480 formal entities in the source, referring to the context available at
  4481 compile-time.  For example:
  4482 
  4483 ML {* @{sort "{zero,one}"} *}
  4484 ML {* @{typ "'a => 'b"} *}
  4485 ML {* @{term "%x. x"} *}
  4486 ML {* @{prop "x == y"} *}
  4487 ML {* @{ctyp "'a => 'b"} *}
  4488 ML {* @{cterm "%x. x"} *}
  4489 ML {* @{cprop "x == y"} *}
  4490 ML {* @{thm asm_rl} *}
  4491 ML {* @{thms asm_rl} *}
  4492 ML {* @{type_name c} *}
  4493 ML {* @{type_syntax c} *}
  4494 ML {* @{const_name c} *}
  4495 ML {* @{const_syntax c} *}
  4496 ML {* @{context} *}
  4497 ML {* @{theory} *}
  4498 ML {* @{theory Pure} *}
  4499 ML {* @{theory_ref} *}
  4500 ML {* @{theory_ref Pure} *}
  4501 ML {* @{simpset} *}
  4502 ML {* @{claset} *}
  4503 ML {* @{clasimpset} *}
  4504 
  4505 The same works for sources being ``used'' within an Isar context.
  4506 
  4507 * ML in Isar: improved error reporting; extra verbosity with
  4508 ML_Context.trace enabled.
  4509 
  4510 * Pure/General/table.ML: the join operations now works via exceptions
  4511 DUP/SAME instead of type option. This is simpler in simple cases, and
  4512 admits slightly more efficient complex applications.
  4513 
  4514 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4515 use Context.generic instead of just theory.
  4516 
  4517 * Pure: datatype Context.generic joins theory/Proof.context and
  4518 provides some facilities for code that works in either kind of
  4519 context, notably GenericDataFun for uniform theory and proof data.
  4520 
  4521 * Pure: simplified internal attribute type, which is now always
  4522 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4523 local (Proof.context) attributes have been discontinued, while
  4524 minimizing code duplication. Thm.rule_attribute and
  4525 Thm.declaration_attribute build canonical attributes; see also structure
  4526 Context for further operations on Context.generic, notably
  4527 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4528 declarations and definitions.
  4529 
  4530 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4531 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4532 init only required for impure data. INCOMPATIBILITY: empty really need
  4533 to be empty (no dependencies on theory content!)
  4534 
  4535 * Pure/kernel: consts certification ignores sort constraints given in
  4536 signature declarations. (This information is not relevant to the
  4537 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4538 potential INCOMPATIBILITY.
  4539 
  4540 * Pure: axiomatic type classes are now purely definitional, with
  4541 explicit proofs of class axioms and super class relations performed
  4542 internally. See Pure/axclass.ML for the main internal interfaces --
  4543 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4544 AxClass.axiomatize_class/classrel/arity supersede
  4545 Sign.add_classes/classrel/arities.
  4546 
  4547 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4548 global/local versions on theory vs. Proof.context have been
  4549 discontinued; Attrib.syntax and Method.syntax have been adapted
  4550 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4551 attributes, methods, etc.
  4552 
  4553 * Pure: several functions of signature "... -> theory -> theory * ..."
  4554 have been reoriented to "... -> theory -> ... * theory" in order to
  4555 allow natural usage in combination with the ||>, ||>>, |-> and
  4556 fold_map combinators.
  4557 
  4558 * Pure: official theorem names (closed derivations) and additional
  4559 comments (tags) are now strictly separate.  Name hints -- which are
  4560 maintained as tags -- may be attached any time without affecting the
  4561 derivation.
  4562 
  4563 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4564 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4565 achieve the old behaviour.
  4566 
  4567 * Pure: the "Goal" constant is now called "prop", supporting a
  4568 slightly more general idea of ``protecting'' meta-level rule
  4569 statements.
  4570 
  4571 * Pure: Logic.(un)varify only works in a global context, which is now
  4572 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4573 Logic.legacy_(un)varify as temporary workaround.
  4574 
  4575 * Pure: structure Name provides scalable operations for generating
  4576 internal variable names, notably Name.variants etc.  This replaces
  4577 some popular functions from term.ML:
  4578 
  4579   Term.variant		->  Name.variant
  4580   Term.variantlist	->  Name.variant_list
  4581   Term.invent_names	->  Name.invent_list
  4582 
  4583 Note that low-level renaming rarely occurs in new code -- operations
  4584 from structure Variable are used instead (see below).
  4585 
  4586 * Pure: structure Variable provides fundamental operations for proper
  4587 treatment of fixed/schematic variables in a context.  For example,
  4588 Variable.import introduces fixes for schematics of given facts and
  4589 Variable.export reverses the effect (up to renaming) -- this replaces
  4590 various freeze_thaw operations.
  4591 
  4592 * Pure: structure Goal provides simple interfaces for
  4593 init/conclude/finish and tactical prove operations (replacing former
  4594 Tactic.prove).  Goal.prove is the canonical way to prove results
  4595 within a given context; Goal.prove_global is a degraded version for
  4596 theory level goals, including a global Drule.standard.  Note that
  4597 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4598 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4599 in a locale context).
  4600 
  4601 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4602 and type checking (Syntax.check_term etc.), with common combinations
  4603 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4604 which are considered legacy and await removal.
  4605 
  4606 * Pure/Syntax: generic interfaces for type unchecking
  4607 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4608 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4609 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4610 available for convenience, but refer to the very same operations using
  4611 a mere theory instead of a full context.
  4612 
  4613 * Isar: simplified treatment of user-level errors, using exception
  4614 ERROR of string uniformly.  Function error now merely raises ERROR,
  4615 without any side effect on output channels.  The Isar toplevel takes
  4616 care of proper display of ERROR exceptions.  ML code may use plain
  4617 handle/can/try; cat_error may be used to concatenate errors like this:
  4618 
  4619   ... handle ERROR msg => cat_error msg "..."
  4620 
  4621 Toplevel ML code (run directly or through the Isar toplevel) may be
  4622 embedded into the Isar toplevel with exception display/debug like
  4623 this:
  4624 
  4625   Isar.toplevel (fn () => ...)
  4626 
  4627 INCOMPATIBILITY, removed special transform_error facilities, removed
  4628 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4629 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4630 -- use plain ERROR instead.
  4631 
  4632 * Isar: theory setup now has type (theory -> theory), instead of a
  4633 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4634 
  4635 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4636 ProofContext.debug/verbose flags.
  4637 
  4638 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4639 theory before entering a proof state.  Transactions now always see a
  4640 quasi-functional intermediate checkpoint, both in interactive and
  4641 batch mode.
  4642 
  4643 * Isar: simplified interfaces for outer syntax.  Renamed
  4644 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4645 OuterSyntax.add_parsers -- this functionality is now included in
  4646 OuterSyntax.command etc.  INCOMPATIBILITY.
  4647 
  4648 * Simplifier: the simpset of a running simplification process now
  4649 contains a proof context (cf. Simplifier.the_context), which is the
  4650 very context that the initial simpset has been retrieved from (by
  4651 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4652 (solver, looper etc.) may depend on arbitrary proof data.
  4653 
  4654 * Simplifier.inherit_context inherits the proof context (plus the
  4655 local bounds) of the current simplification process; any simproc
  4656 etc. that calls the Simplifier recursively should do this!  Removed
  4657 former Simplifier.inherit_bounds, which is already included here --
  4658 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4659 specify an explicit context using Simplifier.context/theory_context.
  4660 
  4661 * Simplifier/Classical Reasoner: more abstract interfaces
  4662 change_simpset/claset for modifying the simpset/claset reference of a
  4663 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4664 INCOMPATIBILITY.
  4665 
  4666 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4667 "Trueprop" etc.
  4668 
  4669 
  4670 *** System ***
  4671 
  4672 * settings: the default heap location within ISABELLE_HOME_USER now
  4673 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4674 Isabelle installations.
  4675 
  4676 * isabelle-process: option -S (secure mode) disables some critical
  4677 operations, notably runtime compilation and evaluation of ML source
  4678 code.
  4679 
  4680 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4681 
  4682 * Support for parallel execution, using native multicore support of
  4683 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4684 independent theories, according to the given theory header
  4685 specifications. The maximum number of worker threads is specified via
  4686 usedir option -M or the "max-threads" setting in Proof General. A
  4687 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4688 to 6 on a 8-core machine.  User-code needs to observe certain
  4689 guidelines for thread-safe programming, see appendix A in the Isar
  4690 Implementation manual.
  4691 
  4692 
  4693 
  4694 New in Isabelle2005 (October 2005)
  4695 ----------------------------------
  4696 
  4697 *** General ***
  4698 
  4699 * Theory headers: the new header syntax for Isar theories is
  4700 
  4701   theory <name>
  4702   imports <theory1> ... <theoryN>
  4703   uses <file1> ... <fileM>
  4704   begin
  4705 
  4706 where the 'uses' part is optional.  The previous syntax
  4707 
  4708   theory <name> = <theory1> + ... + <theoryN>:
  4709 
  4710 will disappear in the next release.  Use isatool fixheaders to convert
  4711 existing theory files.  Note that there is no change in ancient
  4712 non-Isar theories now, but these will disappear soon.
  4713 
  4714 * Theory loader: parent theories can now also be referred to via
  4715 relative and absolute paths.
  4716 
  4717 * Command 'find_theorems' searches for a list of criteria instead of a
  4718 list of constants. Known criteria are: intro, elim, dest, name:string,
  4719 simp:term, and any term. Criteria can be preceded by '-' to select
  4720 theorems that do not match. Intro, elim, dest select theorems that
  4721 match the current goal, name:s selects theorems whose fully qualified
  4722 name contain s, and simp:term selects all simplification rules whose
  4723 lhs match term.  Any other term is interpreted as pattern and selects
  4724 all theorems matching the pattern. Available in ProofGeneral under
  4725 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4726 
  4727   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4728 
  4729 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4730 matching the current goal as introduction rule and not having "HOL."
  4731 in their name (i.e. not being defined in theory HOL).
  4732 
  4733 * Command 'thms_containing' has been discontinued in favour of
  4734 'find_theorems'; INCOMPATIBILITY.
  4735 
  4736 * Communication with Proof General is now 8bit clean, which means that
  4737 Unicode text in UTF-8 encoding may be used within theory texts (both
  4738 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4739 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4740 
  4741   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4742   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4743 
  4744 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4745 Classical Reasoner.  Typical big applications run around 2 times
  4746 faster.
  4747 
  4748 
  4749 *** Document preparation ***
  4750 
  4751 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4752 of raw sources.  Only those symbols that do not require additional
  4753 LaTeX packages (depending on comments in isabellesym.sty) are
  4754 displayed properly, everything else is left verbatim.  isatool display
  4755 and isatool print are used as front ends (these are subject to the
  4756 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4757 
  4758 * Command tags control specific markup of certain regions of text,
  4759 notably folding and hiding.  Predefined tags include "theory" (for
  4760 theory begin and end), "proof" for proof commands, and "ML" for
  4761 commands involving ML code; the additional tags "visible" and
  4762 "invisible" are unused by default.  Users may give explicit tag
  4763 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4764 interpretation of tags is determined by the LaTeX job during document
  4765 preparation: see option -V of isatool usedir, or options -n and -t of
  4766 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4767 \isadroptag.
  4768 
  4769 Several document versions may be produced at the same time via isatool
  4770 usedir (the generated index.html will link all of them).  Typical
  4771 specifications include ''-V document=theory,proof,ML'' to present
  4772 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4773 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4774 these parts without any formal replacement text.  The Isabelle site
  4775 default settings produce ''document'' and ''outline'' versions as
  4776 specified above.
  4777 
  4778 * Several new antiquotations:
  4779 
  4780   @{term_type term} prints a term with its type annotated;
  4781 
  4782   @{typeof term} prints the type of a term;
  4783 
  4784   @{const const} is the same as @{term const}, but checks that the
  4785   argument is a known logical constant;
  4786 
  4787   @{term_style style term} and @{thm_style style thm} print a term or
  4788   theorem applying a "style" to it
  4789 
  4790   @{ML text}
  4791 
  4792 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4793 definitions, equations, inequations etc., 'concl' printing only the
  4794 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4795 to print the specified premise.  TermStyle.add_style provides an ML
  4796 interface for introducing further styles.  See also the "LaTeX Sugar"
  4797 document practical applications.  The ML antiquotation prints
  4798 type-checked ML expressions verbatim.
  4799 
  4800 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4801 and 'text' support optional locale specification '(in loc)', which
  4802 specifies the default context for interpreting antiquotations.  For
  4803 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4804 
  4805 * Option 'locale=NAME' of antiquotations specifies an alternative
  4806 context interpreting the subsequent argument.  For example: @{thm
  4807 [locale=lattice] inf_assoc}.
  4808 
  4809 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4810 a proof context.
  4811 
  4812 * Proper output of antiquotations for theory commands involving a
  4813 proof context (such as 'locale' or 'theorem (in loc) ...').
  4814 
  4815 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4816 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4817 
  4818 * isatool usedir: new option -C (default true) controls whether option
  4819 -D should include a copy of the original document directory; -C false
  4820 prevents unwanted effects such as copying of administrative CVS data.
  4821 
  4822 
  4823 *** Pure ***
  4824 
  4825 * Considerably improved version of 'constdefs' command.  Now performs
  4826 automatic type-inference of declared constants; additional support for
  4827 local structure declarations (cf. locales and HOL records), see also
  4828 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4829 sequential dependencies of definitions within a single 'constdefs'
  4830 section; moreover, the declared name needs to be an identifier.  If
  4831 all fails, consider to fall back on 'consts' and 'defs' separately.
  4832 
  4833 * Improved indexed syntax and implicit structures.  First of all,
  4834 indexed syntax provides a notational device for subscripted
  4835 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4836 expressions.  Secondly, in a local context with structure
  4837 declarations, number indexes \<^sub>n or the empty index (default
  4838 number 1) refer to a certain fixed variable implicitly; option
  4839 show_structs controls printing of implicit structures.  Typical
  4840 applications of these concepts involve record types and locales.
  4841 
  4842 * New command 'no_syntax' removes grammar declarations (and
  4843 translations) resulting from the given syntax specification, which is
  4844 interpreted in the same manner as for the 'syntax' command.
  4845 
  4846 * 'Advanced' translation functions (parse_translation etc.) may depend
  4847 on the signature of the theory context being presently used for
  4848 parsing/printing, see also isar-ref manual.
  4849 
  4850 * Improved 'oracle' command provides a type-safe interface to turn an
  4851 ML expression of type theory -> T -> term into a primitive rule of
  4852 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4853 is already included here); see also FOL/ex/IffExample.thy;
  4854 INCOMPATIBILITY.
  4855 
  4856 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4857 before); "cI" is no longer bound, use "c.intro" instead.
  4858 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4859 axclasses vs. locales.
  4860 
  4861 * Improved internal renaming of symbolic identifiers -- attach primes
  4862 instead of base 26 numbers.
  4863 
  4864 * New flag show_question_marks controls printing of leading question
  4865 marks in schematic variable names.
  4866 
  4867 * In schematic variable names, *any* symbol following \<^isub> or
  4868 \<^isup> is now treated as part of the base name.  For example, the
  4869 following works without printing of awkward ".0" indexes:
  4870 
  4871   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4872     by simp
  4873 
  4874 * Inner syntax includes (*(*nested*) comments*).
  4875 
  4876 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4877 annotations as "(00...)".
  4878 
  4879 * Clear separation of logical types and nonterminals, where the latter
  4880 may only occur in 'syntax' specifications or type abbreviations.
  4881 Before that distinction was only partially implemented via type class
  4882 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4883 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4884 exotic syntax specifications may require further adaption
  4885 (e.g. Cube/Cube.thy).
  4886 
  4887 * Removed obsolete type class "logic", use the top sort {} instead.
  4888 Note that non-logical types should be declared as 'nonterminals'
  4889 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4890 specifications.
  4891 
  4892 * Attributes 'induct' and 'cases': type or set names may now be
  4893 locally fixed variables as well.
  4894 
  4895 * Simplifier: can now control the depth to which conditional rewriting
  4896 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4897 Limit.
  4898 
  4899 * Simplifier: simplification procedures may now take the current
  4900 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4901 interface), which is very useful for calling the Simplifier
  4902 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4903 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4904 low-level mk_simproc no longer applies Logic.varify internally, to
  4905 allow for use in a context of fixed variables.
  4906 
  4907 * thin_tac now works even if the assumption being deleted contains !!
  4908 or ==>.  More generally, erule now works even if the major premise of
  4909 the elimination rule contains !! or ==>.
  4910 
  4911 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4912 
  4913 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4914 from Pure, which contains all common declarations already.  Both
  4915 theories are defined via plain Isabelle/Isar .thy files.
  4916 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4917 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4918 use isatool fixcpure to adapt your theory and ML sources.
  4919 
  4920 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4921 selections of theorems in named facts via index ranges.
  4922 
  4923 * 'print_theorems': in theory mode, really print the difference
  4924 wrt. the last state (works for interactive theory development only),
  4925 in proof mode print all local facts (cf. 'print_facts');
  4926 
  4927 * 'hide': option '(open)' hides only base names.
  4928 
  4929 * More efficient treatment of intermediate checkpoints in interactive
  4930 theory development.
  4931 
  4932 * Code generator is now invoked via code_module (incremental code
  4933 generation) and code_library (modular code generation, ML structures
  4934 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4935 must be quoted when used as identifiers.
  4936 
  4937 * New 'value' command for reading, evaluating and printing terms using
  4938 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4939 quoted when used as identifier.
  4940 
  4941 
  4942 *** Locales ***
  4943 
  4944 * New commands for the interpretation of locale expressions in
  4945 theories (1), locales (2) and proof contexts (3).  These generate
  4946 proof obligations from the expression specification.  After the
  4947 obligations have been discharged, theorems of the expression are added
  4948 to the theory, target locale or proof context.  The synopsis of the
  4949 commands is a follows:
  4950 
  4951   (1) interpretation expr inst
  4952   (2) interpretation target < expr
  4953   (3) interpret expr inst
  4954 
  4955 Interpretation in theories and proof contexts require a parameter
  4956 instantiation of terms from the current context.  This is applied to
  4957 specifications and theorems of the interpreted expression.
  4958 Interpretation in locales only permits parameter renaming through the
  4959 locale expression.  Interpretation is smart in that interpretations
  4960 that are active already do not occur in proof obligations, neither are
  4961 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4962 inspect active interpretations of a particular locale.  For details,
  4963 see the Isar Reference manual.  Examples can be found in
  4964 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4965 
  4966 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4967 'interpret' instead.
  4968 
  4969 * New context element 'constrains' for adding type constraints to
  4970 parameters.
  4971 
  4972 * Context expressions: renaming of parameters with syntax
  4973 redeclaration.
  4974 
  4975 * Locale declaration: 'includes' disallowed.
  4976 
  4977 * Proper static binding of attribute syntax -- i.e. types / terms /
  4978 facts mentioned as arguments are always those of the locale definition
  4979 context, independently of the context of later invocations.  Moreover,
  4980 locale operations (renaming and type / term instantiation) are applied
  4981 to attribute arguments as expected.
  4982 
  4983 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4984 actual attributes; rare situations may require Attrib.attribute to
  4985 embed those attributes into Attrib.src that lack concrete syntax.
  4986 Attribute implementations need to cooperate properly with the static
  4987 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4988 Attrib.XXX_thm etc. already do the right thing without further
  4989 intervention.  Only unusual applications -- such as "where" or "of"
  4990 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4991 on the context and the facts involved -- may have to assign parsed
  4992 values to argument tokens explicitly.
  4993 
  4994 * Changed parameter management in theorem generation for long goal
  4995 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4996 theorem statement in rare situations.
  4997 
  4998 * Locale inspection command 'print_locale' omits notes elements.  Use
  4999 'print_locale!' to have them included in the output.
  5000 
  5001 
  5002 *** Provers ***
  5003 
  5004 * Provers/hypsubst.ML: improved version of the subst method, for
  5005 single-step rewriting: it now works in bound variable contexts. New is
  5006 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  5007 rewrite a different subterm than the original subst method, which is
  5008 still available as 'simplesubst'.
  5009 
  5010 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  5011 and quasi orders.
  5012 
  5013 * Provers/trancl.ML: new transitivity reasoner for transitive and
  5014 reflexive-transitive closure of relations.
  5015 
  5016 * Provers/blast.ML: new reference depth_limit to make blast's depth
  5017 limit (previously hard-coded with a value of 20) user-definable.
  5018 
  5019 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  5020 is peformed already.  Object-logics merely need to finish their
  5021 initial simpset configuration as before.  INCOMPATIBILITY.
  5022 
  5023 
  5024 *** HOL ***
  5025 
  5026 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  5027 
  5028   syntax (epsilon)
  5029     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  5030 
  5031 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  5032 and x-symbol; use option '-m epsilon' to get it actually printed.
  5033 Moreover, the mathematically important symbolic identifier \<epsilon>
  5034 becomes available as variable, constant etc.  INCOMPATIBILITY,
  5035 
  5036 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  5037 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  5038 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  5039 support corresponding Isar calculations.
  5040 
  5041 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  5042 instead of ":".
  5043 
  5044 * theory SetInterval: changed the syntax for open intervals:
  5045 
  5046   Old       New
  5047   {..n(}    {..<n}
  5048   {)n..}    {n<..}
  5049   {m..n(}   {m..<n}
  5050   {)m..n}   {m<..n}
  5051   {)m..n(}  {m<..<n}
  5052 
  5053 The old syntax is still supported but will disappear in the next
  5054 release.  For conversion use the following Emacs search and replace
  5055 patterns (these are not perfect but work quite well):
  5056 
  5057   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  5058   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  5059 
  5060 * Theory Commutative_Ring (in Library): method comm_ring for proving
  5061 equalities in commutative rings; method 'algebra' provides a generic
  5062 interface.
  5063 
  5064 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  5065 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  5066 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  5067 be a tuple pattern.
  5068 
  5069 Some new syntax forms are available:
  5070 
  5071   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  5072   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  5073   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  5074   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  5075 
  5076 The latter form "\<Sum>x < k. e" used to be based on a separate
  5077 function "Summation", which has been discontinued.
  5078 
  5079 * theory Finite_Set: in structured induction proofs, the insert case
  5080 is now 'case (insert x F)' instead of the old counterintuitive 'case
  5081 (insert F x)'.
  5082 
  5083 * The 'refute' command has been extended to support a much larger
  5084 fragment of HOL, including axiomatic type classes, constdefs and
  5085 typedefs, inductive datatypes and recursion.
  5086 
  5087 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  5088 Requires zChaff with proof generation to be installed.  See
  5089 HOL/ex/SAT_Examples.thy for examples.
  5090 
  5091 * Datatype induction via method 'induct' now preserves the name of the
  5092 induction variable. For example, when proving P(xs::'a list) by
  5093 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  5094 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  5095 in unstructured proof scripts.
  5096 
  5097 * Reworked implementation of records.  Improved scalability for
  5098 records with many fields, avoiding performance problems for type
  5099 inference. Records are no longer composed of nested field types, but
  5100 of nested extension types. Therefore the record type only grows linear
  5101 in the number of extensions and not in the number of fields.  The
  5102 top-level (users) view on records is preserved.  Potential
  5103 INCOMPATIBILITY only in strange cases, where the theory depends on the
  5104 old record representation. The type generated for a record is called
  5105 <record_name>_ext_type.
  5106 
  5107 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  5108 proofs triggered by a record definition or a simproc (if
  5109 quick_and_dirty is enabled).  Definitions of large records can take
  5110 quite long.
  5111 
  5112 New simproc record_upd_simproc for simplification of multiple record
  5113 updates enabled by default.  Moreover, trivial updates are also
  5114 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  5115 occasionally, since simplification is more powerful by default.
  5116 
  5117 * typedef: proper support for polymorphic sets, which contain extra
  5118 type-variables in the term.
  5119 
  5120 * Simplifier: automatically reasons about transitivity chains
  5121 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  5122 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  5123 old proofs break occasionally as simplification may now solve more
  5124 goals than previously.
  5125 
  5126 * Simplifier: converts x <= y into x = y if assumption y <= x is
  5127 present.  Works for all partial orders (class "order"), in particular
  5128 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  5129 just like y <= x.
  5130 
  5131 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  5132 bound variable or a constant then the let is unfolded.  Otherwise
  5133 first a is simplified to b, and then f b is simplified to g. If
  5134 possible we abstract b from g arriving at "let x = b in h x",
  5135 otherwise we unfold the let and arrive at g.  The simproc can be
  5136 enabled/disabled by the reference use_let_simproc.  Potential
  5137 INCOMPATIBILITY since simplification is more powerful by default.
  5138 
  5139 * Classical reasoning: the meson method now accepts theorems as arguments.
  5140 
  5141 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  5142 jobs to provide advice on the provability of subgoals.
  5143 
  5144 * Theory OrderedGroup and Ring_and_Field: various additions and
  5145 improvements to faciliate calculations involving equalities and
  5146 inequalities.
  5147 
  5148 The following theorems have been eliminated or modified
  5149 (INCOMPATIBILITY):
  5150 
  5151   abs_eq             now named abs_of_nonneg
  5152   abs_of_ge_0        now named abs_of_nonneg
  5153   abs_minus_eq       now named abs_of_nonpos
  5154   imp_abs_id         now named abs_of_nonneg
  5155   imp_abs_neg_id     now named abs_of_nonpos
  5156   mult_pos           now named mult_pos_pos
  5157   mult_pos_le        now named mult_nonneg_nonneg
  5158   mult_pos_neg_le    now named mult_nonneg_nonpos
  5159   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5160   mult_neg           now named mult_neg_neg
  5161   mult_neg_le        now named mult_nonpos_nonpos
  5162 
  5163 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5164      
  5165      zero_le_square
  5166      not_square_less_zero 
  5167 
  5168   The following lemmas have been deleted from Real/RealPow:
  5169   
  5170      realpow_zero_zero
  5171      realpow_two
  5172      realpow_less
  5173      zero_le_power
  5174      realpow_two_le
  5175      abs_realpow_two
  5176      realpow_two_abs     
  5177 
  5178 * Theory Parity: added rules for simplifying exponents.
  5179 
  5180 * Theory List:
  5181 
  5182 The following theorems have been eliminated or modified
  5183 (INCOMPATIBILITY):
  5184 
  5185   list_all_Nil       now named list_all.simps(1)
  5186   list_all_Cons      now named list_all.simps(2)
  5187   list_all_conv      now named list_all_iff
  5188   set_mem_eq         now named mem_iff
  5189 
  5190 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5191 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5192 
  5193 
  5194 *** HOL-Complex ***
  5195 
  5196 * Theory RealDef: better support for embedding natural numbers and
  5197 integers in the reals.
  5198 
  5199 The following theorems have been eliminated or modified
  5200 (INCOMPATIBILITY):
  5201 
  5202   exp_ge_add_one_self  now requires no hypotheses
  5203   real_of_int_add      reversed direction of equality (use [symmetric])
  5204   real_of_int_minus    reversed direction of equality (use [symmetric])
  5205   real_of_int_diff     reversed direction of equality (use [symmetric])
  5206   real_of_int_mult     reversed direction of equality (use [symmetric])
  5207 
  5208 * Theory RComplete: expanded support for floor and ceiling functions.
  5209 
  5210 * Theory Ln is new, with properties of the natural logarithm
  5211 
  5212 * Hyperreal: There is a new type constructor "star" for making
  5213 nonstandard types.  The old type names are now type synonyms:
  5214 
  5215   hypreal = real star
  5216   hypnat = nat star
  5217   hcomplex = complex star
  5218 
  5219 * Hyperreal: Many groups of similarly-defined constants have been
  5220 replaced by polymorphic versions (INCOMPATIBILITY):
  5221 
  5222   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5223 
  5224   starset      <-- starsetNat, starsetC
  5225   *s*          <-- *sNat*, *sc*
  5226   starset_n    <-- starsetNat_n, starsetC_n
  5227   *sn*         <-- *sNatn*, *scn*
  5228   InternalSets <-- InternalNatSets, InternalCSets
  5229 
  5230   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5231   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5232   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5233   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5234   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5235 
  5236 * Hyperreal: Many type-specific theorems have been removed in favor of
  5237 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5238 
  5239   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5240   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5241   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5242   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5243   right_minus <-- hypreal_add_minus
  5244   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5245   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5246   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5247   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5248   mult_1_right <-- hcomplex_mult_one_right
  5249   mult_zero_left <-- hcomplex_mult_zero_left
  5250   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5251   right_distrib <-- hypnat_add_mult_distrib2
  5252   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5253   right_inverse <-- hypreal_mult_inverse
  5254   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5255   order_refl <-- {hypreal,hypnat}_le_refl
  5256   order_trans <-- {hypreal,hypnat}_le_trans
  5257   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5258   order_less_le <-- {hypreal,hypnat}_less_le
  5259   linorder_linear <-- {hypreal,hypnat}_le_linear
  5260   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5261   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5262   add_nonneg_nonneg <-- hypreal_le_add_order
  5263 
  5264 * Hyperreal: Separate theorems having to do with type-specific
  5265 versions of constants have been merged into theorems that apply to the
  5266 new polymorphic constants (INCOMPATIBILITY):
  5267 
  5268   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5269   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5270   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5271   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5272   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5273   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5274   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5275   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5276   STAR_diff <-- {STAR,STARC}_diff
  5277   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5278     STARC_hcomplex_of_complex}_image_subset
  5279   starset_n_Un <-- starset{Nat,C}_n_Un
  5280   starset_n_Int <-- starset{Nat,C}_n_Int
  5281   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5282   starset_n_diff <-- starset{Nat,C}_n_diff
  5283   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5284   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5285   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5286   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5287   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5288   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5289   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5290   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5291   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5292   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5293   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5294   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5295   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5296   starfun_diff <-- starfun{C,RC,CR}_diff
  5297   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5298   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5299   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5300   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5301   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5302   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5303   starfun_Id <-- starfunC_Id
  5304   starfun_approx <-- starfun{Nat,CR}_approx
  5305   starfun_capprox <-- starfun{C,RC}_capprox
  5306   starfun_abs <-- starfunNat_rabs
  5307   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5308   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5309   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5310   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5311   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5312   starfun_add_approx <-- starfunCR_add_approx
  5313   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5314   starfun_divide <-- starfun{C,CR,RC}_divide
  5315   starfun_n <-- starfun{Nat,C}_n
  5316   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5317   starfun_n_add <-- starfun{Nat,C}_n_add
  5318   starfun_n_add_minus <-- starfunNat_n_add_minus
  5319   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5320   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5321   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5322 
  5323   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5324   star_n_minus <-- {hypreal,hcomplex}_minus
  5325   star_n_diff <-- {hypreal,hcomplex}_diff
  5326   star_n_mult <-- {hypreal,hcomplex}_mult
  5327   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5328   star_n_le <-- {hypreal,hypnat}_le
  5329   star_n_less <-- {hypreal,hypnat}_less
  5330   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5331   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5332   star_n_abs <-- hypreal_hrabs
  5333   star_n_divide <-- hcomplex_divide
  5334 
  5335   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5336   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5337   star_of_diff <-- hypreal_of_real_diff
  5338   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5339   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5340   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5341   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5342   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5343   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5344   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5345   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5346   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5347   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5348   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5349   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5350   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5351   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5352   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5353   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5354   star_of_power <-- hypreal_of_real_power
  5355   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5356 
  5357 * Hyperreal: new method "transfer" that implements the transfer
  5358 principle of nonstandard analysis. With a subgoal that mentions
  5359 nonstandard types like "'a star", the command "apply transfer"
  5360 replaces it with an equivalent one that mentions only standard types.
  5361 To be successful, all free variables must have standard types; non-
  5362 standard variables must have explicit universal quantifiers.
  5363 
  5364 * Hyperreal: A theory of Taylor series.
  5365 
  5366 
  5367 *** HOLCF ***
  5368 
  5369 * Discontinued special version of 'constdefs' (which used to support
  5370 continuous functions) in favor of the general Pure one with full
  5371 type-inference.
  5372 
  5373 * New simplification procedure for solving continuity conditions; it
  5374 is much faster on terms with many nested lambda abstractions (cubic
  5375 instead of exponential time).
  5376 
  5377 * New syntax for domain package: selector names are now optional.
  5378 Parentheses should be omitted unless argument is lazy, for example:
  5379 
  5380   domain 'a stream = cons "'a" (lazy "'a stream")
  5381 
  5382 * New command 'fixrec' for defining recursive functions with pattern
  5383 matching; defining multiple functions with mutual recursion is also
  5384 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5385 sinr, or any data constructor defined by the domain package. The given
  5386 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5387 syntax and examples.
  5388 
  5389 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5390 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5391 but the proof obligation additionally includes an admissibility
  5392 requirement. The packages generate instances of class cpo or pcpo,
  5393 with continuity and strictness theorems for Rep and Abs.
  5394 
  5395 * HOLCF: Many theorems have been renamed according to a more standard naming
  5396 scheme (INCOMPATIBILITY):
  5397 
  5398   foo_inject:  "foo$x = foo$y ==> x = y"
  5399   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5400   foo_less:    "(foo$x << foo$y) = (x << y)"
  5401   foo_strict:  "foo$UU = UU"
  5402   foo_defined: "... ==> foo$x ~= UU"
  5403   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5404 
  5405 
  5406 *** ZF ***
  5407 
  5408 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5409 including the First Isomorphism Theorem (on quotienting by the kernel
  5410 of a homomorphism).
  5411 
  5412 * ZF/Simplifier: install second copy of type solver that actually
  5413 makes use of TC rules declared to Isar proof contexts (or locales);
  5414 the old version is still required for ML proof scripts.
  5415 
  5416 
  5417 *** Cube ***
  5418 
  5419 * Converted to Isar theory format; use locales instead of axiomatic
  5420 theories.
  5421 
  5422 
  5423 *** ML ***
  5424 
  5425 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5426 for ||>, ||>>, |>>,
  5427 
  5428 * Pure/library.ML no longer defines its own option datatype, but uses
  5429 that of the SML basis, which has constructors NONE and SOME instead of
  5430 None and Some, as well as exception Option.Option instead of OPTION.
  5431 The functions the, if_none, is_some, is_none have been adapted
  5432 accordingly, while Option.map replaces apsome.
  5433 
  5434 * Pure/library.ML: the exception LIST has been given up in favour of
  5435 the standard exceptions Empty and Subscript, as well as
  5436 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5437 superceded by the standard hd and tl functions etc.
  5438 
  5439 A number of basic list functions are no longer exported to the ML
  5440 toplevel, as they are variants of predefined functions.  The following
  5441 suggests how one can translate existing code:
  5442 
  5443     rev_append xs ys = List.revAppend (xs, ys)
  5444     nth_elem (i, xs) = List.nth (xs, i)
  5445     last_elem xs = List.last xs
  5446     flat xss = List.concat xss
  5447     seq fs = List.app fs
  5448     partition P xs = List.partition P xs
  5449     mapfilter f xs = List.mapPartial f xs
  5450 
  5451 * Pure/library.ML: several combinators for linear functional
  5452 transformations, notably reverse application and composition:
  5453 
  5454   x |> f                f #> g
  5455   (x, y) |-> f          f #-> g
  5456 
  5457 * Pure/library.ML: introduced/changed precedence of infix operators:
  5458 
  5459   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5460   infix 2 ?;
  5461   infix 3 o oo ooo oooo;
  5462   infix 4 ~~ upto downto;
  5463 
  5464 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5465 infix operators.
  5466 
  5467 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5468 fold_map support linear functional transformations and nesting.  For
  5469 example:
  5470 
  5471   fold f [x1, ..., xN] y =
  5472     y |> f x1 |> ... |> f xN
  5473 
  5474   (fold o fold) f [xs1, ..., xsN] y =
  5475     y |> fold f xs1 |> ... |> fold f xsN
  5476 
  5477   fold f [x1, ..., xN] =
  5478     f x1 #> ... #> f xN
  5479 
  5480   (fold o fold) f [xs1, ..., xsN] =
  5481     fold f xs1 #> ... #> fold f xsN
  5482 
  5483 * Pure/library.ML: the following selectors on type 'a option are
  5484 available:
  5485 
  5486   the:               'a option -> 'a  (*partial*)
  5487   these:             'a option -> 'a  where 'a = 'b list
  5488   the_default: 'a -> 'a option -> 'a
  5489   the_list:          'a option -> 'a list
  5490 
  5491 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5492 basic operations for association lists, following natural argument
  5493 order; moreover the explicit equality predicate passed here avoids
  5494 potentially expensive polymorphic runtime equality checks.
  5495 The old functions may be expressed as follows:
  5496 
  5497   assoc = uncurry (AList.lookup (op =))
  5498   assocs = these oo AList.lookup (op =)
  5499   overwrite = uncurry (AList.update (op =)) o swap
  5500 
  5501 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5502 
  5503   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5504   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5505 
  5506 replacing make_keylist and keyfilter (occassionally used)
  5507 Naive rewrites:
  5508 
  5509   make_keylist = AList.make
  5510   keyfilter = AList.find (op =)
  5511 
  5512 * eq_fst and eq_snd now take explicit equality parameter, thus
  5513   avoiding eqtypes. Naive rewrites:
  5514 
  5515     eq_fst = eq_fst (op =)
  5516     eq_snd = eq_snd (op =)
  5517 
  5518 * Removed deprecated apl and apr (rarely used).
  5519   Naive rewrites:
  5520 
  5521     apl (n, op) =>>= curry op n
  5522     apr (op, m) =>>= fn n => op (n, m)
  5523 
  5524 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5525 provides a reasonably efficient light-weight implementation of sets as
  5526 lists.
  5527 
  5528 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5529 few new operations; existing lookup and update are now curried to
  5530 follow natural argument order (for use with fold etc.);
  5531 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5532 
  5533 * Pure/General: output via the Isabelle channels of
  5534 writeln/warning/error etc. is now passed through Output.output, with a
  5535 hook for arbitrary transformations depending on the print_mode
  5536 (cf. Output.add_mode -- the first active mode that provides a output
  5537 function wins).  Already formatted output may be embedded into further
  5538 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5539 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5540 accommodate easy composition of diagnostic messages etc.  Programmers
  5541 rarely need to care about Output.output or Output.raw at all, with
  5542 some notable exceptions: Output.output is required when bypassing the
  5543 standard channels (writeln etc.), or in token translations to produce
  5544 properly formatted results; Output.raw is required when capturing
  5545 already output material that will eventually be presented to the user
  5546 a second time.  For the default print mode, both Output.output and
  5547 Output.raw have no effect.
  5548 
  5549 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5550 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5551 cumulative results are displayed at the end of a batch session.
  5552 
  5553 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5554 replaced by File.platform_path and File.shell_path (with appropriate
  5555 hooks).  This provides a clean interface for unusual systems where the
  5556 internal and external process view of file names are different.
  5557 
  5558 * Pure: more efficient orders for basic syntactic entities: added
  5559 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5560 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5561 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5562 orders now -- potential INCOMPATIBILITY for code that depends on a
  5563 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5564 Library.sort_strings on result).
  5565 
  5566 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5567 fold_types traverse types/terms from left to right, observing natural
  5568 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5569 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5570 
  5571 * Pure: name spaces have been refined, with significant changes of the
  5572 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5573 to extern(_table).  The plain name entry path is superceded by a
  5574 general 'naming' context, which also includes the 'policy' to produce
  5575 a fully qualified name and external accesses of a fully qualified
  5576 name; NameSpace.extend is superceded by context dependent
  5577 Sign.declare_name.  Several theory and proof context operations modify
  5578 the naming context.  Especially note Theory.restore_naming and
  5579 ProofContext.restore_naming to get back to a sane state; note that
  5580 Theory.add_path is no longer sufficient to recover from
  5581 Theory.absolute_path in particular.
  5582 
  5583 * Pure: new flags short_names (default false) and unique_names
  5584 (default true) for controlling output of qualified names.  If
  5585 short_names is set, names are printed unqualified.  If unique_names is
  5586 reset, the name prefix is reduced to the minimum required to achieve
  5587 the original result when interning again, even if there is an overlap
  5588 with earlier declarations.
  5589 
  5590 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5591 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5592 (useful for printing error messages).  INCOMPATIBILITY.
  5593 
  5594 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5595 Theory.theory are now identified, referring to the universal
  5596 Context.theory (see Pure/context.ML).  Actual signature and theory
  5597 content is managed as theory data.  The old code and interfaces were
  5598 spread over many files and structures; the new arrangement introduces
  5599 considerable INCOMPATIBILITY to gain more clarity:
  5600 
  5601   Context -- theory management operations (name, identity, inclusion,
  5602     parents, ancestors, merge, etc.), plus generic theory data;
  5603 
  5604   Sign -- logical signature and syntax operations (declaring consts,
  5605     types, etc.), plus certify/read for common entities;
  5606 
  5607   Theory -- logical theory operations (stating axioms, definitions,
  5608     oracles), plus a copy of logical signature operations (consts,
  5609     types, etc.); also a few basic management operations (Theory.copy,
  5610     Theory.merge, etc.)
  5611 
  5612 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5613 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5614 for convenience -- they merely return the theory.
  5615 
  5616 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5617 
  5618 * Pure: the Isar proof context type is already defined early in Pure
  5619 as Context.proof (note that ProofContext.context and Proof.context are
  5620 aliases, where the latter is the preferred name).  This enables other
  5621 Isabelle components to refer to that type even before Isar is present.
  5622 
  5623 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5624 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5625 any of these kinds.  For example, Sign.intern typeK is now
  5626 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5627 Theory.hide_types.  Also note that former
  5628 Theory.hide_classes/types/consts are now
  5629 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5630 internalize their arguments!  INCOMPATIBILITY.
  5631 
  5632 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5633 datatype thmref (with constructors Name and NameSelection) instead of
  5634 plain string -- INCOMPATIBILITY;
  5635 
  5636 * Pure: cases produced by proof methods specify options, where NONE
  5637 means to remove case bindings -- INCOMPATIBILITY in
  5638 (RAW_)METHOD_CASES.
  5639 
  5640 * Pure: the following operations retrieve axioms or theorems from a
  5641 theory node or theory hierarchy, respectively:
  5642 
  5643   Theory.axioms_of: theory -> (string * term) list
  5644   Theory.all_axioms_of: theory -> (string * term) list
  5645   PureThy.thms_of: theory -> (string * thm) list
  5646   PureThy.all_thms_of: theory -> (string * thm) list
  5647 
  5648 * Pure: print_tac now outputs the goal through the trace channel.
  5649 
  5650 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5651 Reference Toplevel.debug (default false) controls detailed printing
  5652 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5653 controls execution profiling -- set to 1 for time and 2 for space
  5654 (both increase the runtime).
  5655 
  5656 * Isar session: The initial use of ROOT.ML is now always timed,
  5657 i.e. the log will show the actual process times, in contrast to the
  5658 elapsed wall-clock time that the outer shell wrapper produces.
  5659 
  5660 * Simplifier: improved handling of bound variables (nameless
  5661 representation, avoid allocating new strings).  Simprocs that invoke
  5662 the Simplifier recursively should use Simplifier.inherit_bounds to
  5663 avoid local name clashes.  Failure to do so produces warnings
  5664 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5665 for further details.
  5666 
  5667 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5668 bindings for all theorems stored within a given theory; this may help
  5669 in porting non-Isar theories to Isar ones, while keeping ML proof
  5670 scripts for the time being.
  5671 
  5672 * ML operator HTML.with_charset specifies the charset begin used for
  5673 generated HTML files.  For example:
  5674 
  5675   HTML.with_charset "utf-8" use_thy "Hebrew";
  5676   HTML.with_charset "utf-8" use_thy "Chinese";
  5677 
  5678 
  5679 *** System ***
  5680 
  5681 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5682 isabelle, isatool etc.).
  5683 
  5684 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5685 isatool doc, isatool mkdir, display_drafts etc.).
  5686 
  5687 * isatool usedir: option -f allows specification of the ML file to be
  5688 used by Isabelle; default is ROOT.ML.
  5689 
  5690 * New isatool version outputs the version identifier of the Isabelle
  5691 distribution being used.
  5692 
  5693 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5694 (containing Boolean satisfiability problems) into Isabelle/HOL
  5695 theories.
  5696 
  5697 
  5698 
  5699 New in Isabelle2004 (April 2004)
  5700 --------------------------------
  5701 
  5702 *** General ***
  5703 
  5704 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5705   Replaces linorder.ML.
  5706 
  5707 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5708   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5709   (\<a>...\<z>), are now considered normal letters, and can therefore
  5710   be used anywhere where an ASCII letter (a...zA...Z) has until
  5711   now. COMPATIBILITY: This obviously changes the parsing of some
  5712   terms, especially where a symbol has been used as a binder, say
  5713   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5714   as an identifier.  Fix it by inserting a space around former
  5715   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5716   existing theory and ML files.
  5717 
  5718 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5719 
  5720 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5721   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5722   a normal (but invisible) letter. For multiple letter subscripts repeat
  5723   \<^isub> like this: x\<^isub>1\<^isub>2.
  5724 
  5725 * Pure: There are now sub-/superscripts that can span more than one
  5726   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5727   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5728   superscript. The new control characters are not identifier parts.
  5729 
  5730 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5731   content of "..." to the latex file instead of \isacntrl... . The "..."
  5732   may consist of any printable characters excluding the end bracket >.
  5733 
  5734 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5735   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5736   declare constants "final", which prevents their being given a definition
  5737   later.  It is useful for constants whose behaviour is fixed axiomatically
  5738   rather than definitionally, such as the meta-logic connectives.
  5739 
  5740 * Pure: 'instance' now handles general arities with general sorts
  5741   (i.e. intersections of classes),
  5742 
  5743 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5744   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5745   It can be changed to alter the colors/layout of generated pages.
  5746 
  5747 
  5748 *** Isar ***
  5749 
  5750 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5751   cut_tac, subgoal_tac and thin_tac:
  5752   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5753     locales are no longer forced to write Isar proof scripts.
  5754     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5755     emulations.
  5756   - INCOMPATIBILITY: names of variables to be instantiated may no
  5757     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5758     This is consistent with the instantiation attribute "where".
  5759 
  5760 * Attributes "where" and "of":
  5761   - Now take type variables of instantiated theorem into account when reading
  5762     the instantiation string.  This fixes a bug that caused instantiated
  5763     theorems to have too special types in some circumstances.
  5764   - "where" permits explicit instantiations of type variables.
  5765 
  5766 * Calculation commands "moreover" and "also" no longer interfere with
  5767   current facts ("this"), admitting arbitrary combinations with "then"
  5768   and derived forms.
  5769 
  5770 * Locales:
  5771   - Goal statements involving the context element "includes" no longer
  5772     generate theorems with internal delta predicates (those ending on
  5773     "_axioms") in the premise.
  5774     Resolve particular premise with <locale>.intro to obtain old form.
  5775   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5776     specification and "includes" elements in goal statement.
  5777   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5778     [intro?] and [elim?] (respectively) by default.
  5779   - Experimental command for instantiation of locales in proof contexts:
  5780         instantiate <label>[<attrs>]: <loc>
  5781     Instantiates locale <loc> and adds all its theorems to the current context
  5782     taking into account their attributes.  Label and attrs are optional
  5783     modifiers, like in theorem declarations.  If present, names of
  5784     instantiated theorems are qualified with <label>, and the attributes
  5785     <attrs> are applied after any attributes these theorems might have already.
  5786       If the locale has assumptions, a chained fact of the form
  5787     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5788     are derived.  The command does not support old-style locales declared
  5789     with "locale (open)".
  5790       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5791 
  5792 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5793   (Isar) contexts.
  5794 
  5795 
  5796 *** HOL ***
  5797 
  5798 * Proof import: new image HOL4 contains the imported library from
  5799   the HOL4 system with about 2500 theorems. It is imported by
  5800   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5801   can be used like any other Isabelle image.  See
  5802   HOL/Import/HOL/README for more information.
  5803 
  5804 * Simplifier:
  5805   - Much improved handling of linear and partial orders.
  5806     Reasoners for linear and partial orders are set up for type classes
  5807     "linorder" and "order" respectively, and are added to the default simpset
  5808     as solvers.  This means that the simplifier can build transitivity chains
  5809     to solve goals from the assumptions.
  5810   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5811     of blast or auto after simplification become unnecessary because the goal
  5812     is solved by simplification already.
  5813 
  5814 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5815     all proved in axiomatic type classes for semirings, rings and fields.
  5816 
  5817 * Numerics:
  5818   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5819     now formalized using the Ring_and_Field theory mentioned above.
  5820   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5821     than before, because now they are set up once in a generic manner.
  5822   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5823     Look for the general versions in Ring_and_Field (and Power if they concern
  5824     exponentiation).
  5825 
  5826 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5827 
  5828 * Records:
  5829   - Record types are now by default printed with their type abbreviation
  5830     instead of the list of all field types. This can be configured via
  5831     the reference "print_record_type_abbr".
  5832   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5833     (not enabled by default).
  5834   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5835     EX x. x = sel r to True (not enabled by default).
  5836   - Tactic "record_split_simp_tac" to split and simplify records added.
  5837 
  5838 * 'specification' command added, allowing for definition by
  5839   specification.  There is also an 'ax_specification' command that
  5840   introduces the new constants axiomatically.
  5841 
  5842 * arith(_tac) is now able to generate counterexamples for reals as well.
  5843 
  5844 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5845 
  5846 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5847   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5848 
  5849 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5850   matrix theory to linear programming.
  5851 
  5852 * Unions and Intersections:
  5853   The latex output syntax of UN and INT has been changed
  5854   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5855   i.e. the index formulae has become a subscript.
  5856   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5857 
  5858 * Unions and Intersections over Intervals:
  5859   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5860   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5861   like in normal math, and corresponding versions for < and for intersection.
  5862 
  5863 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5864   lexicographic dictonary ordering has been added as "lexord".
  5865 
  5866 * ML: the legacy theory structures Int and List have been removed. They had
  5867   conflicted with ML Basis Library structures having the same names.
  5868 
  5869 * 'refute' command added to search for (finite) countermodels.  Only works
  5870   for a fragment of HOL.  The installation of an external SAT solver is
  5871   highly recommended.  See "HOL/Refute.thy" for details.
  5872 
  5873 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5874   formulae under an assignment of free variables to random values.
  5875   In contrast to 'refute', it can deal with inductive datatypes,
  5876   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5877   for examples.
  5878 
  5879 
  5880 *** HOLCF ***
  5881 
  5882 * Streams now come with concatenation and are part of the HOLCF image
  5883 
  5884 
  5885 
  5886 New in Isabelle2003 (May 2003)
  5887 ------------------------------
  5888 
  5889 *** General ***
  5890 
  5891 * Provers/simplifier:
  5892 
  5893   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5894     Assumptions are now subject to complete mutual simplification,
  5895     not just from left to right. The simplifier now preserves
  5896     the order of assumptions.
  5897 
  5898     Potential INCOMPATIBILITY:
  5899 
  5900     -- simp sometimes diverges where the old version did
  5901        not, e.g. invoking simp on the goal
  5902 
  5903         [| P (f x); y = x; f x = f y |] ==> Q
  5904 
  5905        now gives rise to the infinite reduction sequence
  5906 
  5907         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5908 
  5909        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5910        kind of problem.
  5911 
  5912     -- Tactics combining classical reasoner and simplification (such as auto)
  5913        are also affected by this change, because many of them rely on
  5914        simp. They may sometimes diverge as well or yield a different numbers
  5915        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5916        in case of problems. Sometimes subsequent calls to the classical
  5917        reasoner will fail because a preceeding call to the simplifier too
  5918        eagerly simplified the goal, e.g. deleted redundant premises.
  5919 
  5920   - The simplifier trace now shows the names of the applied rewrite rules
  5921 
  5922   - You can limit the number of recursive invocations of the simplifier
  5923     during conditional rewriting (where the simplifie tries to solve the
  5924     conditions before applying the rewrite rule):
  5925     ML "simp_depth_limit := n"
  5926     where n is an integer. Thus you can force termination where previously
  5927     the simplifier would diverge.
  5928 
  5929   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5930 
  5931   - No longer aborts on failed congruence proof.  Instead, the
  5932     congruence is ignored.
  5933 
  5934 * Pure: New generic framework for extracting programs from constructive
  5935   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5936   as HOL/Extraction for some case studies.
  5937 
  5938 * Pure: The main goal of the proof state is no longer shown by default, only
  5939 the subgoals. This behaviour is controlled by a new flag.
  5940    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5941 (ML: Proof.show_main_goal).
  5942 
  5943 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5944 rules whose conclusion matches subgoal 1:
  5945       PG menu: Isabelle/Isar -> Show me -> matching rules
  5946 The rules are ordered by how closely they match the subgoal.
  5947 In particular, rules that solve a subgoal outright are displayed first
  5948 (or rather last, the way they are printed).
  5949 (ML: ProofGeneral.print_intros())
  5950 
  5951 * Pure: New flag trace_unify_fail causes unification to print
  5952 diagnostic information (PG: in trace buffer) when it fails. This is
  5953 useful for figuring out why single step proofs like rule, erule or
  5954 assumption failed.
  5955 
  5956 * Pure: Locale specifications now produce predicate definitions
  5957 according to the body of text (covering assumptions modulo local
  5958 definitions); predicate "loc_axioms" covers newly introduced text,
  5959 while "loc" is cumulative wrt. all included locale expressions; the
  5960 latter view is presented only on export into the global theory
  5961 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5962 on the old view without predicates;
  5963 
  5964 * Pure: predefined locales "var" and "struct" are useful for sharing
  5965 parameters (as in CASL, for example); just specify something like
  5966 ``var x + var y + struct M'' as import;
  5967 
  5968 * Pure: improved thms_containing: proper indexing of facts instead of
  5969 raw theorems; check validity of results wrt. current name space;
  5970 include local facts of proof configuration (also covers active
  5971 locales), cover fixed variables in index; may use "_" in term
  5972 specification; an optional limit for the number of printed facts may
  5973 be given (the default is 40);
  5974 
  5975 * Pure: disallow duplicate fact bindings within new-style theory files
  5976 (batch-mode only);
  5977 
  5978 * Provers: improved induct method: assumptions introduced by case
  5979 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5980 the goal statement); "foo" still refers to all facts collectively;
  5981 
  5982 * Provers: the function blast.overloaded has been removed: all constants
  5983 are regarded as potentially overloaded, which improves robustness in exchange
  5984 for slight decrease in efficiency;
  5985 
  5986 * Provers/linorder: New generic prover for transitivity reasoning over
  5987 linear orders.  Note: this prover is not efficient!
  5988 
  5989 * Isar: preview of problems to finish 'show' now produce an error
  5990 rather than just a warning (in interactive mode);
  5991 
  5992 
  5993 *** HOL ***
  5994 
  5995 * arith(_tac)
  5996 
  5997  - Produces a counter example if it cannot prove a goal.
  5998    Note that the counter example may be spurious if the goal is not a formula
  5999    of quantifier-free linear arithmetic.
  6000    In ProofGeneral the counter example appears in the trace buffer.
  6001 
  6002  - Knows about div k and mod k where k is a numeral of type nat or int.
  6003 
  6004  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  6005    linear arithmetic fails. This takes account of quantifiers and divisibility.
  6006    Presburger arithmetic can also be called explicitly via presburger(_tac).
  6007 
  6008 * simp's arithmetic capabilities have been enhanced a bit: it now
  6009 takes ~= in premises into account (by performing a case split);
  6010 
  6011 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  6012 are distributed over a sum of terms;
  6013 
  6014 * New tactic "trans_tac" and method "trans" instantiate
  6015 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  6016 "<=", "<" and "=").
  6017 
  6018 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  6019 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  6020 
  6021 * 'typedef' command has new option "open" to suppress the set
  6022 definition;
  6023 
  6024 * functions Min and Max on finite sets have been introduced (theory
  6025 Finite_Set);
  6026 
  6027 * attribute [symmetric] now works for relations as well; it turns
  6028 (x,y) : R^-1 into (y,x) : R, and vice versa;
  6029 
  6030 * induct over a !!-quantified statement (say !!x1..xn):
  6031   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  6032 
  6033 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  6034 %x. None. Warning: empty_def now refers to the previously hidden definition
  6035 of the empty set.
  6036 
  6037 * Algebra: formalization of classical algebra.  Intended as base for
  6038 any algebraic development in Isabelle.  Currently covers group theory
  6039 (up to Sylow's theorem) and ring theory (Universal Property of
  6040 Univariate Polynomials).  Contributions welcome;
  6041 
  6042 * GroupTheory: deleted, since its material has been moved to Algebra;
  6043 
  6044 * Complex: new directory of the complex numbers with numeric constants,
  6045 nonstandard complex numbers, and some complex analysis, standard and
  6046 nonstandard (Jacques Fleuriot);
  6047 
  6048 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  6049 
  6050 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  6051 Fleuriot);
  6052 
  6053 * Real/HahnBanach: updated and adapted to locales;
  6054 
  6055 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  6056 Gray and Kramer);
  6057 
  6058 * UNITY: added the Meier-Sanders theory of progress sets;
  6059 
  6060 * MicroJava: bytecode verifier and lightweight bytecode verifier
  6061 as abstract algorithms, instantiated to the JVM;
  6062 
  6063 * Bali: Java source language formalization. Type system, operational
  6064 semantics, axiomatic semantics. Supported language features:
  6065 classes, interfaces, objects,virtual methods, static methods,
  6066 static/instance fields, arrays, access modifiers, definite
  6067 assignment, exceptions.
  6068 
  6069 
  6070 *** ZF ***
  6071 
  6072 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  6073 universe, etc.);
  6074 
  6075 * Main ZF: virtually all theories converted to new-style format;
  6076 
  6077 
  6078 *** ML ***
  6079 
  6080 * Pure: Tactic.prove provides sane interface for internal proofs;
  6081 omits the infamous "standard" operation, so this is more appropriate
  6082 than prove_goalw_cterm in many situations (e.g. in simprocs);
  6083 
  6084 * Pure: improved error reporting of simprocs;
  6085 
  6086 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  6087 up simprocs;
  6088 
  6089 
  6090 *** Document preparation ***
  6091 
  6092 * uses \par instead of \\ for line breaks in theory text. This may
  6093 shift some page breaks in large documents. To get the old behaviour
  6094 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  6095 
  6096 * minimized dependencies of isabelle.sty and isabellesym.sty on
  6097 other packages
  6098 
  6099 * \<euro> now needs package babel/greek instead of marvosym (which
  6100 broke \Rightarrow)
  6101 
  6102 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  6103 textcomp package)
  6104 
  6105 
  6106 
  6107 New in Isabelle2002 (March 2002)
  6108 --------------------------------
  6109 
  6110 *** Document preparation ***
  6111 
  6112 * greatly simplified document preparation setup, including more
  6113 graceful interpretation of isatool usedir -i/-d/-D options, and more
  6114 instructive isatool mkdir; users should basically be able to get
  6115 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  6116 users may run a separate document processing stage manually like this:
  6117 "isatool usedir -D output HOL Test && isatool document Test/output";
  6118 
  6119 * theory dependency graph may now be incorporated into documents;
  6120 isatool usedir -g true will produce session_graph.eps/.pdf for use
  6121 with \includegraphics of LaTeX;
  6122 
  6123 * proper spacing of consecutive markup elements, especially text
  6124 blocks after section headings;
  6125 
  6126 * support bold style (for single symbols only), input syntax is like
  6127 this: "\<^bold>\<alpha>" or "\<^bold>A";
  6128 
  6129 * \<bullet> is now output as bold \cdot by default, which looks much
  6130 better in printed text;
  6131 
  6132 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  6133 note that these symbols are currently unavailable in Proof General /
  6134 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  6135 
  6136 * isatool latex no longer depends on changed TEXINPUTS, instead
  6137 isatool document copies the Isabelle style files to the target
  6138 location;
  6139 
  6140 
  6141 *** Isar ***
  6142 
  6143 * Pure/Provers: improved proof by cases and induction;
  6144   - 'case' command admits impromptu naming of parameters (such as
  6145     "case (Suc n)");
  6146   - 'induct' method divinates rule instantiation from the inductive
  6147     claim; no longer requires excessive ?P bindings for proper
  6148     instantiation of cases;
  6149   - 'induct' method properly enumerates all possibilities of set/type
  6150     rules; as a consequence facts may be also passed through *type*
  6151     rules without further ado;
  6152   - 'induct' method now derives symbolic cases from the *rulified*
  6153     rule (before it used to rulify cases stemming from the internal
  6154     atomized version); this means that the context of a non-atomic
  6155     statement becomes is included in the hypothesis, avoiding the
  6156     slightly cumbersome show "PROP ?case" form;
  6157   - 'induct' may now use elim-style induction rules without chaining
  6158     facts, using ``missing'' premises from the goal state; this allows
  6159     rules stemming from inductive sets to be applied in unstructured
  6160     scripts, while still benefitting from proper handling of non-atomic
  6161     statements; NB: major inductive premises need to be put first, all
  6162     the rest of the goal is passed through the induction;
  6163   - 'induct' proper support for mutual induction involving non-atomic
  6164     rule statements (uses the new concept of simultaneous goals, see
  6165     below);
  6166   - append all possible rule selections, but only use the first
  6167     success (no backtracking);
  6168   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  6169   - undeclared rule case names default to numbers 1, 2, 3, ...;
  6170   - added 'print_induct_rules' (covered by help item in recent Proof
  6171     General versions);
  6172   - moved induct/cases attributes to Pure, methods to Provers;
  6173   - generic method setup instantiated for FOL and HOL;
  6174 
  6175 * Pure: support multiple simultaneous goal statements, for example
  6176 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  6177 meta-level mechanism, this acts as if several individual goals had
  6178 been stated separately; in particular common proof methods need to be
  6179 repeated in order to cover all claims; note that a single elimination
  6180 step is *not* sufficient to establish the two conjunctions, so this
  6181 fails:
  6182 
  6183   assume "A & B" then have A and B ..   (*".." fails*)
  6184 
  6185 better use "obtain" in situations as above; alternative refer to
  6186 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  6187 
  6188 * Pure: proper integration with ``locales''; unlike the original
  6189 version by Florian Kammller, Isar locales package high-level proof
  6190 contexts rather than raw logical ones (e.g. we admit to include
  6191 attributes everywhere); operations on locales include merge and
  6192 rename; support for implicit arguments (``structures''); simultaneous
  6193 type-inference over imports and text; see also HOL/ex/Locales.thy for
  6194 some examples;
  6195 
  6196 * Pure: the following commands have been ``localized'', supporting a
  6197 target locale specification "(in name)": 'lemma', 'theorem',
  6198 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  6199 stored both within the locale and at the theory level (exported and
  6200 qualified by the locale name);
  6201 
  6202 * Pure: theory goals may now be specified in ``long'' form, with
  6203 ad-hoc contexts consisting of arbitrary locale elements. for example
  6204 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  6205 definitions may be given, too); the result is a meta-level rule with
  6206 the context elements being discharged in the obvious way;
  6207 
  6208 * Pure: new proof command 'using' allows to augment currently used
  6209 facts after a goal statement ('using' is syntactically analogous to
  6210 'apply', but acts on the goal's facts only); this allows chained facts
  6211 to be separated into parts given before and after a claim, as in
  6212 ``from a and b have C using d and e <proof>'';
  6213 
  6214 * Pure: renamed "antecedent" case to "rule_context";
  6215 
  6216 * Pure: new 'judgment' command records explicit information about the
  6217 object-logic embedding (used by several tools internally); no longer
  6218 use hard-wired "Trueprop";
  6219 
  6220 * Pure: added 'corollary' command;
  6221 
  6222 * Pure: fixed 'token_translation' command;
  6223 
  6224 * Pure: removed obsolete 'exported' attribute;
  6225 
  6226 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  6227 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  6228 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  6229 
  6230 * Pure: method 'atomize' presents local goal premises as object-level