NEWS
author huffman
Thu Aug 18 13:36:58 2011 -0700 (2011-08-18)
changeset 44282 f0de18b62d63
parent 44274 731b18266d5a
child 44322 43b465f4c480
permissions -rw-r--r--
remove bounded_(bi)linear locale interpretations, to avoid duplicating so many lemmas
     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 * Attribute case_names has been refined: the assumptions in each case can
    61 be named now by following the case name with [name1 name2 ...].
    62 
    63 
    64 *** HOL ***
    65 
    66 * Classes bot and top require underlying partial order rather than preorder:
    67 uniqueness of bot and top is guaranteed.  INCOMPATIBILITY.
    68 
    69 * Class complete_lattice: generalized a couple of lemmas from sets;
    70 generalized theorems INF_cong and SUP_cong.  New type classes for complete
    71 boolean algebras and complete linear orders.  Lemmas Inf_less_iff,
    72 less_Sup_iff, INF_less_iff, less_SUP_iff now reside in class complete_linorder.
    73 Changed proposition of lemmas Inf_fun_def, Sup_fun_def, Inf_apply, Sup_apply.
    74 Redundant lemmas Inf_singleton, Sup_singleton, Inf_binary, Sup_binary,
    75 INF_eq, SUP_eq, INF_UNIV_range, SUP_UNIV_range, Int_eq_Inter,
    76 INTER_eq_Inter_image, Inter_def, INT_eq, Un_eq_Union, UNION_eq_Union_image,
    77 Union_def, UN_singleton, UN_eq have been discarded.
    78 More consistent and less misunderstandable names:
    79   INFI_def ~> INF_def
    80   SUPR_def ~> SUP_def
    81   INF_leI ~> INF_lower
    82   INF_leI2 ~> INF_lower2
    83   le_INFI ~> INF_greatest
    84   le_SUPI ~> SUP_upper
    85   le_SUPI2 ~> SUP_upper2
    86   SUP_leI ~> SUP_least
    87   INFI_bool_eq ~> INF_bool_eq
    88   SUPR_bool_eq ~> SUP_bool_eq
    89   INFI_apply ~> INF_apply
    90   SUPR_apply ~> SUP_apply
    91   INTER_def ~> INTER_eq
    92   UNION_def ~> UNION_eq
    93 
    94 INCOMPATIBILITY.
    95 
    96 * Theorem collections ball_simps and bex_simps do not contain theorems referring
    97 to UNION any longer;  these have been moved to collection UN_ball_bex_simps.
    98 INCOMPATIBILITY.
    99 
   100 * Archimedean_Field.thy:
   101     floor now is defined as parameter of a separate type class floor_ceiling.
   102  
   103 * Finite_Set.thy: more coherent development of fold_set locales:
   104 
   105     locale fun_left_comm ~> locale comp_fun_commute
   106     locale fun_left_comm_idem ~> locale comp_fun_idem
   107     
   108 Both use point-free characterisation; interpretation proofs may need adjustment.
   109 INCOMPATIBILITY.
   110 
   111 * Code generation:
   112   - theory Library/Code_Char_ord provides native ordering of characters
   113     in the target language.
   114   - commands code_module and code_library are legacy, use export_code instead. 
   115   - method evaluation is legacy, use method eval instead.
   116   - legacy evaluator "SML" is deactivated by default. To activate it, add the following
   117     line in your theory:
   118       setup {* Value.add_evaluator ("SML", Codegen.eval_term) *}
   119  
   120 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
   121 
   122 * Nitpick:
   123   - Added "need" and "total_consts" options.
   124   - Reintroduced "show_skolems" option by popular demand.
   125   - Renamed attribute: nitpick_def ~> nitpick_unfold.
   126     INCOMPATIBILITY.
   127 
   128 * Sledgehammer:
   129   - sledgehammer available_provers ~> sledgehammer supported_provers.
   130     INCOMPATIBILITY.
   131   - Added support for SNARK and ToFoF-E on SystemOnTPTP and for simply typed
   132     TPTP problems (TFF).
   133   - Added "preplay_timeout", "slicing", "type_enc", "sound", "max_mono_iters",
   134     and "max_new_mono_instances" options.
   135   - Removed "explicit_apply" and "full_types" options as well as "Full Types"
   136     Proof General menu item. INCOMPATIBILITY.
   137 
   138 * Metis:
   139   - Removed "metisF" -- use "metis" instead. INCOMPATIBILITY.
   140   - Obsoleted "metisFT" -- use "metis (full_types)" instead. INCOMPATIBILITY.
   141 
   142 * "try":
   143   - Renamed "try_methods" and added "simp:", "intro:", "dest:", and "elim:"
   144     options. INCOMPATIBILITY.
   145   - Introduced "try" that not only runs "try_methods" but also "solve_direct",
   146     "sledgehammer", "quickcheck", and "nitpick".
   147 
   148 * Quickcheck:
   149   - Added "eval" option to evaluate terms for the found counterexample
   150     (currently only supported by the default (exhaustive) tester)
   151   - Added post-processing of terms to obtain readable counterexamples
   152     (currently only supported by the default (exhaustive) tester)
   153   - New counterexample generator quickcheck[narrowing] enables
   154     narrowing-based testing.
   155     It requires that the Glasgow Haskell compiler is installed and
   156     its location is known to Isabelle with the environment variable
   157     ISABELLE_GHC.
   158   - Removed quickcheck tester "SML" based on the SML code generator
   159     from HOL-Library
   160 
   161 * Function package: discontinued option "tailrec".
   162 INCOMPATIBILITY. Use partial_function instead.
   163 
   164 * HOL-Probability:
   165   - Caratheodory's extension lemma is now proved for ring_of_sets.
   166   - Infinite products of probability measures are now available.
   167   - Use extended reals instead of positive extended reals.
   168     INCOMPATIBILITY.
   169 
   170 * Old recdef package has been moved to Library/Old_Recdef.thy, where it
   171 must be loaded explicitly.  INCOMPATIBILITY.
   172 
   173 * Well-founded recursion combinator "wfrec" has been moved to
   174 Library/Wfrec.thy. INCOMPATIBILITY.
   175 
   176 * Theory Library/Nat_Infinity has been renamed to Library/Extended_Nat.
   177 The names of the following types and constants have changed:
   178   inat (type) ~> enat
   179   Fin         ~> enat
   180   Infty       ~> infinity (overloaded)
   181   iSuc        ~> eSuc
   182   the_Fin     ~> the_enat
   183 Every theorem name containing "inat", "Fin", "Infty", or "iSuc" has
   184 been renamed accordingly.
   185 
   186 * Limits.thy: Type "'a net" has been renamed to "'a filter", in
   187 accordance with standard mathematical terminology. INCOMPATIBILITY.
   188 
   189 * Session Multivariate_Analysis: Type "('a, 'b) cart" has been renamed
   190 to "('a, 'b) vec" (the syntax "'a ^ 'b" remains unaffected). Constants
   191 "Cart_nth" and "Cart_lambda" have been respectively renamed to
   192 "vec_nth" and "vec_lambda"; theorems mentioning those names have
   193 changed to match. Definition theorems for overloaded constants now use
   194 the standard "foo_vec_def" naming scheme. A few other theorems have
   195 been renamed as follows (INCOMPATIBILITY):
   196 
   197   Cart_eq          ~> vec_eq_iff
   198   dist_nth_le_cart ~> dist_vec_nth_le
   199   tendsto_vector   ~> vec_tendstoI
   200   Cauchy_vector    ~> vec_CauchyI
   201 
   202 * Complex_Main: The locale interpretations for the bounded_linear and
   203 bounded_bilinear locales have been removed, in order to reduce the
   204 number of duplicate lemmas. Users must use the original names for
   205 distributivity theorems, potential INCOMPATIBILITY.
   206 
   207   divide.add ~> add_divide_distrib
   208   divide.diff ~> diff_divide_distrib
   209   divide.setsum ~> setsum_divide_distrib
   210   mult.add_right ~> right_distrib
   211   mult.diff_right ~> right_diff_distrib
   212   mult_right.setsum ~> setsum_right_distrib
   213   mult_left.diff ~> left_diff_distrib
   214 
   215 
   216 *** Document preparation ***
   217 
   218 * Discontinued special treatment of hard tabulators, which are better
   219 avoided in the first place.  Implicit tab-width is 1.
   220 
   221 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
   222 isar-ref manual.
   223 
   224 * Antiquotation @{value} evaluates the given term and presents its result.
   225 
   226 * Localized \isabellestyle switch can be used within blocks or groups
   227 like this:
   228 
   229   \isabellestyle{it}  %preferred default
   230   {\isabellestylett @{text "typewriter stuff"}}
   231 
   232 * New term style "isub" as ad-hoc conversion of variables x1, y23 into
   233 subscripted form x\<^isub>1, y\<^isub>2\<^isub>3.
   234 
   235 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
   236 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
   237 
   238 
   239 *** ML ***
   240 
   241 * The inner syntax of sort/type/term/prop supports inlined YXML
   242 representations within quoted string tokens.  By encoding logical
   243 entities via Term_XML (in ML or Scala) concrete syntax can be
   244 bypassed, which is particularly useful for producing bits of text
   245 under external program control.
   246 
   247 * Antiquotations for ML and document preparation are managed as theory
   248 data, which requires explicit setup.
   249 
   250 * Isabelle_Process.is_active allows tools to check if the official
   251 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
   252 (better known as Proof General).
   253 
   254 * Structure Proof_Context follows standard naming scheme.  Old
   255 ProofContext is still available for some time as legacy alias.
   256 
   257 * Structure Timing provides various operations for timing; supersedes
   258 former start_timing/end_timing etc.
   259 
   260 * Path.print is the official way to show file-system paths to users
   261 (including quotes etc.).
   262 
   263 * Inner syntax: identifiers in parse trees of generic categories
   264 "logic", "aprop", "idt" etc. carry position information (disguised as
   265 type constraints).  Occasional INCOMPATIBILITY with non-compliant
   266 translations that choke on unexpected type constraints.  Positions can
   267 be stripped in ML translations via Syntax.strip_positions /
   268 Syntax.strip_positions_ast, or via the syntax constant
   269 "_strip_positions" within parse trees.  As last resort, positions can
   270 be disabled via the configuration option Syntax.positions, which is
   271 called "syntax_positions" in Isar attribute syntax.
   272 
   273 * Discontinued special status of various ML structures that contribute
   274 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
   275 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
   276 refer directly to Ast.Constant, Lexicon.is_identifier,
   277 Syntax_Trans.mk_binder_tr etc.
   278 
   279 * Typed print translation: discontinued show_sorts argument, which is
   280 already available via context of "advanced" translation.
   281 
   282 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
   283 goal states; body tactic needs to address all subgoals uniformly.
   284 
   285 * Slightly more special eq_list/eq_set, with shortcut involving
   286 pointer equality (assumes that eq relation is reflexive).
   287 
   288 * Classical tactics use proper Proof.context instead of historic types
   289 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
   290 operate directly on Proof.context.  Raw type claset retains its use as
   291 snapshot of the classical context, which can be recovered via
   292 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
   293 INCOMPATIBILITY, classical tactics and derived proof methods require
   294 proper Proof.context.
   295 
   296 * Scala layer provides JVM method invocation service for static
   297 methods of type (String)String, see Invoke_Scala.method in ML.
   298 For example:
   299 
   300   Invoke_Scala.method "java.lang.System.getProperty" "java.home"
   301 
   302 
   303 
   304 New in Isabelle2011 (January 2011)
   305 ----------------------------------
   306 
   307 *** General ***
   308 
   309 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
   310 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
   311 useful tooltips and hyperlinks produced from its static analysis.  The
   312 bundled component provides an executable Isabelle tool that can be run
   313 like this:
   314 
   315   Isabelle2011/bin/isabelle jedit
   316 
   317 * Significantly improved Isabelle/Isar implementation manual.
   318 
   319 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
   320 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
   321 while the default heap location within that directory lacks that extra
   322 suffix.  This isolates multiple Isabelle installations from each
   323 other, avoiding problems with old settings in new versions.
   324 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
   325 
   326 * Source files are always encoded as UTF-8, instead of old-fashioned
   327 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   328 the following package declarations:
   329 
   330   \usepackage[utf8]{inputenc}
   331   \usepackage{textcomp}
   332 
   333 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   334 a Unicode character is treated as a single symbol, not a sequence of
   335 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   336 contain symbols without further backslash escapes, Unicode can now be
   337 used here as well.  Recall that Symbol.explode in ML provides a
   338 consistent view on symbols, while raw explode (or String.explode)
   339 merely give a byte-oriented representation.
   340 
   341 * Theory loader: source files are primarily located via the master
   342 directory of each theory node (where the .thy file itself resides).
   343 The global load path is still partially available as legacy feature.
   344 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   345 explicit paths, relatively to the theory.
   346 
   347 * Special treatment of ML file names has been discontinued.
   348 Historically, optional extensions .ML or .sml were added on demand --
   349 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   350 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   351 
   352 * Various options that affect pretty printing etc. are now properly
   353 handled within the context via configuration options, instead of
   354 unsynchronized references or print modes.  There are both ML Config.T
   355 entities and Isar declaration attributes to access these.
   356 
   357   ML (Config.T)                 Isar (attribute)
   358 
   359   eta_contract                  eta_contract
   360   show_brackets                 show_brackets
   361   show_sorts                    show_sorts
   362   show_types                    show_types
   363   show_question_marks           show_question_marks
   364   show_consts                   show_consts
   365   show_abbrevs                  show_abbrevs
   366 
   367   Syntax.ast_trace              syntax_ast_trace
   368   Syntax.ast_stat               syntax_ast_stat
   369   Syntax.ambiguity_level        syntax_ambiguity_level
   370 
   371   Goal_Display.goals_limit      goals_limit
   372   Goal_Display.show_main_goal   show_main_goal
   373 
   374   Method.rule_trace             rule_trace
   375 
   376   Thy_Output.display            thy_output_display
   377   Thy_Output.quotes             thy_output_quotes
   378   Thy_Output.indent             thy_output_indent
   379   Thy_Output.source             thy_output_source
   380   Thy_Output.break              thy_output_break
   381 
   382 Note that corresponding "..._default" references in ML may only be
   383 changed globally at the ROOT session setup, but *not* within a theory.
   384 The option "show_abbrevs" supersedes the former print mode
   385 "no_abbrevs" with inverted meaning.
   386 
   387 * More systematic naming of some configuration options.
   388 INCOMPATIBILITY.
   389 
   390   trace_simp  ~>  simp_trace
   391   debug_simp  ~>  simp_debug
   392 
   393 * Support for real valued configuration options, using simplistic
   394 floating-point notation that coincides with the inner syntax for
   395 float_token.
   396 
   397 * Support for real valued preferences (with approximative PGIP type):
   398 front-ends need to accept "pgint" values in float notation.
   399 INCOMPATIBILITY.
   400 
   401 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   402 DejaVu Sans.
   403 
   404 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   405 
   406 
   407 *** Pure ***
   408 
   409 * Command 'type_synonym' (with single argument) replaces somewhat
   410 outdated 'types', which is still available as legacy feature for some
   411 time.
   412 
   413 * Command 'nonterminal' (with 'and' separated list of arguments)
   414 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   415 
   416 * Command 'notepad' replaces former 'example_proof' for
   417 experimentation in Isar without any result.  INCOMPATIBILITY.
   418 
   419 * Locale interpretation commands 'interpret' and 'sublocale' accept
   420 lists of equations to map definitions in a locale to appropriate
   421 entities in the context of the interpretation.  The 'interpretation'
   422 command already provided this functionality.
   423 
   424 * Diagnostic command 'print_dependencies' prints the locale instances
   425 that would be activated if the specified expression was interpreted in
   426 the current context.  Variant "print_dependencies!" assumes a context
   427 without interpretations.
   428 
   429 * Diagnostic command 'print_interps' prints interpretations in proofs
   430 in addition to interpretations in theories.
   431 
   432 * Discontinued obsolete 'global' and 'local' commands to manipulate
   433 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   434 Sign.root_path and Sign.local_path may be applied directly where this
   435 feature is still required for historical reasons.
   436 
   437 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   438 'definition' instead.
   439 
   440 * The "prems" fact, which refers to the accidental collection of
   441 foundational premises in the context, is now explicitly marked as
   442 legacy feature and will be discontinued soon.  Consider using "assms"
   443 of the head statement or reference facts by explicit names.
   444 
   445 * Document antiquotations @{class} and @{type} print classes and type
   446 constructors.
   447 
   448 * Document antiquotation @{file} checks file/directory entries within
   449 the local file system.
   450 
   451 
   452 *** HOL ***
   453 
   454 * Coercive subtyping: functions can be declared as coercions and type
   455 inference will add them as necessary upon input of a term.  Theory
   456 Complex_Main declares real :: nat => real and real :: int => real as
   457 coercions. A coercion function f is declared like this:
   458 
   459   declare [[coercion f]]
   460 
   461 To lift coercions through type constructors (e.g. from nat => real to
   462 nat list => real list), map functions can be declared, e.g.
   463 
   464   declare [[coercion_map map]]
   465 
   466 Currently coercion inference is activated only in theories including
   467 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   468 the configuration option "coercion_enabled", e.g. it can be enabled in
   469 other theories like this:
   470 
   471   declare [[coercion_enabled]]
   472 
   473 * Command 'partial_function' provides basic support for recursive
   474 function definitions over complete partial orders.  Concrete instances
   475 are provided for i) the option type, ii) tail recursion on arbitrary
   476 types, and iii) the heap monad of Imperative_HOL.  See
   477 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   478 for examples.
   479 
   480 * Function package: f.psimps rules are no longer implicitly declared
   481 as [simp].  INCOMPATIBILITY.
   482 
   483 * Datatype package: theorems generated for executable equality (class
   484 "eq") carry proper names and are treated as default code equations.
   485 
   486 * Inductive package: now offers command 'inductive_simps' to
   487 automatically derive instantiated and simplified equations for
   488 inductive predicates, similar to 'inductive_cases'.
   489 
   490 * Command 'enriched_type' allows to register properties of the
   491 functorial structure of types.
   492 
   493 * Improved infrastructure for term evaluation using code generator
   494 techniques, in particular static evaluation conversions.
   495 
   496 * Code generator: Scala (2.8 or higher) has been added to the target
   497 languages.
   498 
   499 * Code generator: globbing constant expressions "*" and "Theory.*"
   500 have been replaced by the more idiomatic "_" and "Theory._".
   501 INCOMPATIBILITY.
   502 
   503 * Code generator: export_code without explicit file declaration prints
   504 to standard output.  INCOMPATIBILITY.
   505 
   506 * Code generator: do not print function definitions for case
   507 combinators any longer.
   508 
   509 * Code generator: simplification with rules determined with
   510 src/Tools/Code/code_simp.ML and method "code_simp".
   511 
   512 * Code generator for records: more idiomatic representation of record
   513 types.  Warning: records are not covered by ancient SML code
   514 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   515 rep_datatype declaration helps to succeed then:
   516 
   517   record 'a foo = ...
   518   ...
   519   rep_datatype foo_ext ...
   520 
   521 * Records: logical foundation type for records does not carry a
   522 '_type' suffix any longer (obsolete due to authentic syntax).
   523 INCOMPATIBILITY.
   524 
   525 * Quickcheck now by default uses exhaustive testing instead of random
   526 testing.  Random testing can be invoked by "quickcheck [random]",
   527 exhaustive testing by "quickcheck [exhaustive]".
   528 
   529 * Quickcheck instantiates polymorphic types with small finite
   530 datatypes by default. This enables a simple execution mechanism to
   531 handle quantifiers and function equality over the finite datatypes.
   532 
   533 * Quickcheck random generator has been renamed from "code" to
   534 "random".  INCOMPATIBILITY.
   535 
   536 * Quickcheck now has a configurable time limit which is set to 30
   537 seconds by default. This can be changed by adding [timeout = n] to the
   538 quickcheck command. The time limit for Auto Quickcheck is still set
   539 independently.
   540 
   541 * Quickcheck in locales considers interpretations of that locale for
   542 counter example search.
   543 
   544 * Sledgehammer:
   545   - Added "smt" and "remote_smt" provers based on the "smt" proof
   546     method. See the Sledgehammer manual for details ("isabelle doc
   547     sledgehammer").
   548   - Renamed commands:
   549     sledgehammer atp_info ~> sledgehammer running_provers
   550     sledgehammer atp_kill ~> sledgehammer kill_provers
   551     sledgehammer available_atps ~> sledgehammer available_provers
   552     INCOMPATIBILITY.
   553   - Renamed options:
   554     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   555     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   556     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   557     (and "ms" and "min" are no longer supported)
   558     INCOMPATIBILITY.
   559 
   560 * Nitpick:
   561   - Renamed options:
   562     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   563     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   564     INCOMPATIBILITY.
   565   - Added support for partial quotient types.
   566   - Added local versions of the "Nitpick.register_xxx" functions.
   567   - Added "whack" option.
   568   - Allow registration of quotient types as codatatypes.
   569   - Improved "merge_type_vars" option to merge more types.
   570   - Removed unsound "fast_descrs" option.
   571   - Added custom symmetry breaking for datatypes, making it possible to reach
   572     higher cardinalities.
   573   - Prevent the expansion of too large definitions.
   574 
   575 * Proof methods "metis" and "meson" now have configuration options
   576 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   577 to diagnose these tools. E.g.
   578 
   579     using [[metis_trace = true]]
   580 
   581 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   582 manually as command 'solve_direct'.
   583 
   584 * The default SMT solver Z3 must be enabled explicitly (due to
   585 licensing issues) by setting the environment variable
   586 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   587 commercial applications, the SMT solver CVC3 is provided as fall-back;
   588 changing the SMT solver is done via the configuration option
   589 "smt_solver".
   590 
   591 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   592 i.e. "remote_cvc3" and "remote_z3".
   593 
   594 * Added basic SMT support for datatypes, records, and typedefs using
   595 the oracle mode (no proofs).  Direct support of pairs has been dropped
   596 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   597 support for a similar behavior).  Minor INCOMPATIBILITY.
   598 
   599 * Changed SMT configuration options:
   600   - Renamed:
   601     z3_proofs ~> smt_oracle (with inverted meaning)
   602     z3_trace_assms ~> smt_trace_used_facts
   603     INCOMPATIBILITY.
   604   - Added:
   605     smt_verbose
   606     smt_random_seed
   607     smt_datatypes
   608     smt_infer_triggers
   609     smt_monomorph_limit
   610     cvc3_options
   611     remote_cvc3_options
   612     remote_z3_options
   613     yices_options
   614 
   615 * Boogie output files (.b2i files) need to be declared in the theory
   616 header.
   617 
   618 * Simplification procedure "list_to_set_comprehension" rewrites list
   619 comprehensions applied to List.set to set comprehensions.  Occasional
   620 INCOMPATIBILITY, may be deactivated like this:
   621 
   622   declare [[simproc del: list_to_set_comprehension]]
   623 
   624 * Removed old version of primrec package.  INCOMPATIBILITY.
   625 
   626 * Removed simplifier congruence rule of "prod_case", as has for long
   627 been the case with "split".  INCOMPATIBILITY.
   628 
   629 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   630 
   631 * Removed [split_format ... and ... and ...] version of
   632 [split_format].  Potential INCOMPATIBILITY.
   633 
   634 * Predicate "sorted" now defined inductively, with nice induction
   635 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   636 
   637 * Constant "contents" renamed to "the_elem", to free the generic name
   638 contents for other uses.  INCOMPATIBILITY.
   639 
   640 * Renamed class eq and constant eq (for code generation) to class
   641 equal and constant equal, plus renaming of related facts and various
   642 tuning.  INCOMPATIBILITY.
   643 
   644 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   645 
   646 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   647 INCOMPATIBILITY.
   648 
   649 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   650 avoid confusion with finite sets.  INCOMPATIBILITY.
   651 
   652 * Abandoned locales equiv, congruent and congruent2 for equivalence
   653 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   654 for congruent(2)).
   655 
   656 * Some previously unqualified names have been qualified:
   657 
   658   types
   659     bool ~> HOL.bool
   660     nat ~> Nat.nat
   661 
   662   constants
   663     Trueprop ~> HOL.Trueprop
   664     True ~> HOL.True
   665     False ~> HOL.False
   666     op & ~> HOL.conj
   667     op | ~> HOL.disj
   668     op --> ~> HOL.implies
   669     op = ~> HOL.eq
   670     Not ~> HOL.Not
   671     The ~> HOL.The
   672     All ~> HOL.All
   673     Ex ~> HOL.Ex
   674     Ex1 ~> HOL.Ex1
   675     Let ~> HOL.Let
   676     If ~> HOL.If
   677     Ball ~> Set.Ball
   678     Bex ~> Set.Bex
   679     Suc ~> Nat.Suc
   680     Pair ~> Product_Type.Pair
   681     fst ~> Product_Type.fst
   682     snd ~> Product_Type.snd
   683     curry ~> Product_Type.curry
   684     op : ~> Set.member
   685     Collect ~> Set.Collect
   686 
   687 INCOMPATIBILITY.
   688 
   689 * More canonical naming convention for some fundamental definitions:
   690 
   691     bot_bool_eq ~> bot_bool_def
   692     top_bool_eq ~> top_bool_def
   693     inf_bool_eq ~> inf_bool_def
   694     sup_bool_eq ~> sup_bool_def
   695     bot_fun_eq  ~> bot_fun_def
   696     top_fun_eq  ~> top_fun_def
   697     inf_fun_eq  ~> inf_fun_def
   698     sup_fun_eq  ~> sup_fun_def
   699 
   700 INCOMPATIBILITY.
   701 
   702 * More stylized fact names:
   703 
   704   expand_fun_eq ~> fun_eq_iff
   705   expand_set_eq ~> set_eq_iff
   706   set_ext       ~> set_eqI
   707   nat_number    ~> eval_nat_numeral
   708 
   709 INCOMPATIBILITY.
   710 
   711 * Refactoring of code-generation specific operations in theory List:
   712 
   713   constants
   714     null ~> List.null
   715 
   716   facts
   717     mem_iff ~> member_def
   718     null_empty ~> null_def
   719 
   720 INCOMPATIBILITY.  Note that these were not supposed to be used
   721 regularly unless for striking reasons; their main purpose was code
   722 generation.
   723 
   724 Various operations from the Haskell prelude are used for generating
   725 Haskell code.
   726 
   727 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   728 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   729 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   730 
   731 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   732 "*" and "+" respectively.  INCOMPATIBILITY.
   733 
   734 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   735 "Sum_Type.Plus" instead.
   736 
   737 * Constant "split" has been merged with constant "prod_case"; names of
   738 ML functions, facts etc. involving split have been retained so far,
   739 though.  INCOMPATIBILITY.
   740 
   741 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   742 instead.  INCOMPATIBILITY.
   743 
   744 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   745 INCOMPATIBILITY.
   746 
   747 * Former theory Library/Enum is now part of the HOL-Main image.
   748 INCOMPATIBILITY: all constants of the Enum theory now have to be
   749 referred to by its qualified name.
   750 
   751   enum    ~>  Enum.enum
   752   nlists  ~>  Enum.nlists
   753   product ~>  Enum.product
   754 
   755 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   756 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   757 INCOMPATIBILITY.
   758 
   759 * Theory Library/SetsAndFunctions has been split into
   760 Library/Function_Algebras and Library/Set_Algebras; canonical names
   761 for instance definitions for functions; various improvements.
   762 INCOMPATIBILITY.
   763 
   764 * Theory Library/Multiset provides stable quicksort implementation of
   765 sort_key.
   766 
   767 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   768 INCOMPATIBILITY.
   769 
   770 * Session Multivariate_Analysis: introduced a type class for euclidean
   771 space.  Most theorems are now stated in terms of euclidean spaces
   772 instead of finite cartesian products.
   773 
   774   types
   775     real ^ 'n ~>  'a::real_vector
   776               ~>  'a::euclidean_space
   777               ~>  'a::ordered_euclidean_space
   778         (depends on your needs)
   779 
   780   constants
   781      _ $ _        ~> _ $$ _
   782      \<chi> x. _  ~> \<chi>\<chi> x. _
   783      CARD('n)     ~> DIM('a)
   784 
   785 Also note that the indices are now natural numbers and not from some
   786 finite type. Finite cartesian products of euclidean spaces, products
   787 of euclidean spaces the real and complex numbers are instantiated to
   788 be euclidean_spaces.  INCOMPATIBILITY.
   789 
   790 * Session Probability: introduced pextreal as positive extended real
   791 numbers.  Use pextreal as value for measures.  Introduce the
   792 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   793 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   794 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   795 
   796 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   797 INCOMPATIBILITY.
   798 
   799 * Session SPARK (with image HOL-SPARK) provides commands to load and
   800 prove verification conditions generated by the SPARK Ada program
   801 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   802 
   803 
   804 *** HOL-Algebra ***
   805 
   806 * Theorems for additive ring operations (locale abelian_monoid and
   807 descendants) are generated by interpretation from their multiplicative
   808 counterparts.  Names (in particular theorem names) have the mandatory
   809 qualifier 'add'.  Previous theorem names are redeclared for
   810 compatibility.
   811 
   812 * Structure "int_ring" is now an abbreviation (previously a
   813 definition).  This fits more natural with advanced interpretations.
   814 
   815 
   816 *** HOLCF ***
   817 
   818 * The domain package now runs in definitional mode by default: The
   819 former command 'new_domain' is now called 'domain'.  To use the domain
   820 package in its original axiomatic mode, use 'domain (unsafe)'.
   821 INCOMPATIBILITY.
   822 
   823 * The new class "domain" is now the default sort.  Class "predomain"
   824 is an unpointed version of "domain". Theories can be updated by
   825 replacing sort annotations as shown below.  INCOMPATIBILITY.
   826 
   827   'a::type ~> 'a::countable
   828   'a::cpo  ~> 'a::predomain
   829   'a::pcpo ~> 'a::domain
   830 
   831 * The old type class "rep" has been superseded by class "domain".
   832 Accordingly, users of the definitional package must remove any
   833 "default_sort rep" declarations.  INCOMPATIBILITY.
   834 
   835 * The domain package (definitional mode) now supports unpointed
   836 predomain argument types, as long as they are marked 'lazy'. (Strict
   837 arguments must be in class "domain".) For example, the following
   838 domain definition now works:
   839 
   840   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   841 
   842 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   843 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   844 'a option, and 'a list.  Additionally, it configures fixrec and the
   845 domain package to work with these types.  For example:
   846 
   847   fixrec isInl :: "('a + 'b) u -> tr"
   848     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   849 
   850   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   851 
   852 * The "(permissive)" option of fixrec has been replaced with a
   853 per-equation "(unchecked)" option. See
   854 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
   855 
   856 * The "bifinite" class no longer fixes a constant "approx"; the class
   857 now just asserts that such a function exists.  INCOMPATIBILITY.
   858 
   859 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
   860 defines an embedding of type 'a defl into udom by default; instances
   861 of "bifinite" and "domain" classes are available in
   862 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
   863 
   864 * The syntax "REP('a)" has been replaced with "DEFL('a)".
   865 
   866 * The predicate "directed" has been removed.  INCOMPATIBILITY.
   867 
   868 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
   869 
   870 * The function "cprod_map" has been renamed to "prod_map".
   871 INCOMPATIBILITY.
   872 
   873 * The monadic bind operator on each powerdomain has new binder syntax
   874 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
   875 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
   876 
   877 * The infix syntax for binary union on each powerdomain has changed
   878 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
   879 syntax.  INCOMPATIBILITY.
   880 
   881 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
   882 still supported as an input translation.
   883 
   884 * Renamed some theorems (the original names are also still available).
   885 
   886   expand_fun_below   ~> fun_below_iff
   887   below_fun_ext      ~> fun_belowI
   888   expand_cfun_eq     ~> cfun_eq_iff
   889   ext_cfun           ~> cfun_eqI
   890   expand_cfun_below  ~> cfun_below_iff
   891   below_cfun_ext     ~> cfun_belowI
   892   cont2cont_Rep_CFun ~> cont2cont_APP
   893 
   894 * The Abs and Rep functions for various types have changed names.
   895 Related theorem names have also changed to match. INCOMPATIBILITY.
   896 
   897   Rep_CFun  ~> Rep_cfun
   898   Abs_CFun  ~> Abs_cfun
   899   Rep_Sprod ~> Rep_sprod
   900   Abs_Sprod ~> Abs_sprod
   901   Rep_Ssum  ~> Rep_ssum
   902   Abs_Ssum  ~> Abs_ssum
   903 
   904 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   905 been renamed to *_bottom_iff.  INCOMPATIBILITY.
   906 
   907 * Various changes to bisimulation/coinduction with domain package:
   908 
   909   - Definitions of "bisim" constants no longer mention definedness.
   910   - With mutual recursion, "bisim" predicate is now curried.
   911   - With mutual recursion, each type gets a separate coind theorem.
   912   - Variable names in bisim_def and coinduct rules have changed.
   913 
   914 INCOMPATIBILITY.
   915 
   916 * Case combinators generated by the domain package for type "foo" are
   917 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
   918 
   919 * Several theorems have been renamed to more accurately reflect the
   920 names of constants and types involved.  INCOMPATIBILITY.
   921 
   922   thelub_const    ~> lub_const
   923   lub_const       ~> is_lub_const
   924   thelubI         ~> lub_eqI
   925   is_lub_lub      ~> is_lubD2
   926   lubI            ~> is_lub_lub
   927   unique_lub      ~> is_lub_unique
   928   is_ub_lub       ~> is_lub_rangeD1
   929   lub_bin_chain   ~> is_lub_bin_chain
   930   lub_fun         ~> is_lub_fun
   931   thelub_fun      ~> lub_fun
   932   thelub_cfun     ~> lub_cfun
   933   thelub_Pair     ~> lub_Pair
   934   lub_cprod       ~> is_lub_prod
   935   thelub_cprod    ~> lub_prod
   936   minimal_cprod   ~> minimal_prod
   937   inst_cprod_pcpo ~> inst_prod_pcpo
   938   UU_I            ~> bottomI
   939   compact_UU      ~> compact_bottom
   940   deflation_UU    ~> deflation_bottom
   941   finite_deflation_UU ~> finite_deflation_bottom
   942 
   943 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
   944 
   945   sq_ord_less_eq_trans ~> below_eq_trans
   946   sq_ord_eq_less_trans ~> eq_below_trans
   947   refl_less            ~> below_refl
   948   trans_less           ~> below_trans
   949   antisym_less         ~> below_antisym
   950   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
   951   box_less             ~> box_below
   952   rev_trans_less       ~> rev_below_trans
   953   not_less2not_eq      ~> not_below2not_eq
   954   less_UU_iff          ~> below_UU_iff
   955   flat_less_iff        ~> flat_below_iff
   956   adm_less             ~> adm_below
   957   adm_not_less         ~> adm_not_below
   958   adm_compact_not_less ~> adm_compact_not_below
   959   less_fun_def         ~> below_fun_def
   960   expand_fun_less      ~> fun_below_iff
   961   less_fun_ext         ~> fun_belowI
   962   less_discr_def       ~> below_discr_def
   963   discr_less_eq        ~> discr_below_eq
   964   less_unit_def        ~> below_unit_def
   965   less_cprod_def       ~> below_prod_def
   966   prod_lessI           ~> prod_belowI
   967   Pair_less_iff        ~> Pair_below_iff
   968   fst_less_iff         ~> fst_below_iff
   969   snd_less_iff         ~> snd_below_iff
   970   expand_cfun_less     ~> cfun_below_iff
   971   less_cfun_ext        ~> cfun_belowI
   972   injection_less       ~> injection_below
   973   less_up_def          ~> below_up_def
   974   not_Iup_less         ~> not_Iup_below
   975   Iup_less             ~> Iup_below
   976   up_less              ~> up_below
   977   Def_inject_less_eq   ~> Def_below_Def
   978   Def_less_is_eq       ~> Def_below_iff
   979   spair_less_iff       ~> spair_below_iff
   980   less_sprod           ~> below_sprod
   981   spair_less           ~> spair_below
   982   sfst_less_iff        ~> sfst_below_iff
   983   ssnd_less_iff        ~> ssnd_below_iff
   984   fix_least_less       ~> fix_least_below
   985   dist_less_one        ~> dist_below_one
   986   less_ONE             ~> below_ONE
   987   ONE_less_iff         ~> ONE_below_iff
   988   less_sinlD           ~> below_sinlD
   989   less_sinrD           ~> below_sinrD
   990 
   991 
   992 *** FOL and ZF ***
   993 
   994 * All constant names are now qualified internally and use proper
   995 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
   996 
   997 
   998 *** ML ***
   999 
  1000 * Antiquotation @{assert} inlines a function bool -> unit that raises
  1001 Fail if the argument is false.  Due to inlining the source position of
  1002 failed assertions is included in the error output.
  1003 
  1004 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
  1005 text is in practice always evaluated with a stable theory checkpoint.
  1006 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
  1007 
  1008 * Antiquotation @{theory A} refers to theory A from the ancestry of
  1009 the current context, not any accidental theory loader state as before.
  1010 Potential INCOMPATIBILITY, subtle change in semantics.
  1011 
  1012 * Syntax.pretty_priority (default 0) configures the required priority
  1013 of pretty-printed output and thus affects insertion of parentheses.
  1014 
  1015 * Syntax.default_root (default "any") configures the inner syntax
  1016 category (nonterminal symbol) for parsing of terms.
  1017 
  1018 * Former exception Library.UnequalLengths now coincides with
  1019 ListPair.UnequalLengths.
  1020 
  1021 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
  1022 main functionality is provided by structure Simplifier.
  1023 
  1024 * Renamed raw "explode" function to "raw_explode" to emphasize its
  1025 meaning.  Note that internally to Isabelle, Symbol.explode is used in
  1026 almost all situations.
  1027 
  1028 * Discontinued obsolete function sys_error and exception SYS_ERROR.
  1029 See implementation manual for further details on exceptions in
  1030 Isabelle/ML.
  1031 
  1032 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
  1033 meaning.
  1034 
  1035 * Renamed structure PureThy to Pure_Thy and moved most of its
  1036 operations to structure Global_Theory, to emphasize that this is
  1037 rarely-used global-only stuff.
  1038 
  1039 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
  1040 instead (or tracing for high-volume output).
  1041 
  1042 * Configuration option show_question_marks only affects regular pretty
  1043 printing of types and terms, not raw Term.string_of_vname.
  1044 
  1045 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
  1046 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
  1047 @{thms} for most purposes.
  1048 
  1049 * ML structure Unsynchronized is never opened, not even in Isar
  1050 interaction mode as before.  Old Unsynchronized.set etc. have been
  1051 discontinued -- use plain := instead.  This should be *rare* anyway,
  1052 since modern tools always work via official context data, notably
  1053 configuration options.
  1054 
  1055 * Parallel and asynchronous execution requires special care concerning
  1056 interrupts.  Structure Exn provides some convenience functions that
  1057 avoid working directly with raw Interrupt.  User code must not absorb
  1058 interrupts -- intermediate handling (for cleanup etc.) needs to be
  1059 followed by re-raising of the original exception.  Another common
  1060 source of mistakes are "handle _" patterns, which make the meaning of
  1061 the program subject to physical effects of the environment.
  1062 
  1063 
  1064 
  1065 New in Isabelle2009-2 (June 2010)
  1066 ---------------------------------
  1067 
  1068 *** General ***
  1069 
  1070 * Authentic syntax for *all* logical entities (type classes, type
  1071 constructors, term constants): provides simple and robust
  1072 correspondence between formal entities and concrete syntax.  Within
  1073 the parse tree / AST representations, "constants" are decorated by
  1074 their category (class, type, const) and spelled out explicitly with
  1075 their full internal name.
  1076 
  1077 Substantial INCOMPATIBILITY concerning low-level syntax declarations
  1078 and translations (translation rules and translation functions in ML).
  1079 Some hints on upgrading:
  1080 
  1081   - Many existing uses of 'syntax' and 'translations' can be replaced
  1082     by more modern 'type_notation', 'notation' and 'abbreviation',
  1083     which are independent of this issue.
  1084 
  1085   - 'translations' require markup within the AST; the term syntax
  1086     provides the following special forms:
  1087 
  1088       CONST c   -- produces syntax version of constant c from context
  1089       XCONST c  -- literally c, checked as constant from context
  1090       c         -- literally c, if declared by 'syntax'
  1091 
  1092     Plain identifiers are treated as AST variables -- occasionally the
  1093     system indicates accidental variables via the error "rhs contains
  1094     extra variables".
  1095 
  1096     Type classes and type constructors are marked according to their
  1097     concrete syntax.  Some old translations rules need to be written
  1098     for the "type" category, using type constructor application
  1099     instead of pseudo-term application of the default category
  1100     "logic".
  1101 
  1102   - 'parse_translation' etc. in ML may use the following
  1103     antiquotations:
  1104 
  1105       @{class_syntax c}   -- type class c within parse tree / AST
  1106       @{term_syntax c}    -- type constructor c within parse tree / AST
  1107       @{const_syntax c}   -- ML version of "CONST c" above
  1108       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
  1109 
  1110   - Literal types within 'typed_print_translations', i.e. those *not*
  1111     represented as pseudo-terms are represented verbatim.  Use @{class
  1112     c} or @{type_name c} here instead of the above syntax
  1113     antiquotations.
  1114 
  1115 Note that old non-authentic syntax was based on unqualified base
  1116 names, so all of the above "constant" names would coincide.  Recall
  1117 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
  1118 diagnose syntax problems.
  1119 
  1120 * Type constructors admit general mixfix syntax, not just infix.
  1121 
  1122 * Concrete syntax may be attached to local entities without a proof
  1123 body, too.  This works via regular mixfix annotations for 'fix',
  1124 'def', 'obtain' etc. or via the explicit 'write' command, which is
  1125 similar to the 'notation' command in theory specifications.
  1126 
  1127 * Discontinued unnamed infix syntax (legacy feature for many years) --
  1128 need to specify constant name and syntax separately.  Internal ML
  1129 datatype constructors have been renamed from InfixName to Infix etc.
  1130 Minor INCOMPATIBILITY.
  1131 
  1132 * Schematic theorem statements need to be explicitly markup as such,
  1133 via commands 'schematic_lemma', 'schematic_theorem',
  1134 'schematic_corollary'.  Thus the relevance of the proof is made
  1135 syntactically clear, which impacts performance in a parallel or
  1136 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  1137 
  1138 * Use of cumulative prems via "!" in some proof methods has been
  1139 discontinued (old legacy feature).
  1140 
  1141 * References 'trace_simp' and 'debug_simp' have been replaced by
  1142 configuration options stored in the context. Enabling tracing (the
  1143 case of debugging is similar) in proofs works via
  1144 
  1145   using [[trace_simp = true]]
  1146 
  1147 Tracing is then active for all invocations of the simplifier in
  1148 subsequent goal refinement steps. Tracing may also still be enabled or
  1149 disabled via the ProofGeneral settings menu.
  1150 
  1151 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  1152 'hide_fact' replace the former 'hide' KIND command.  Minor
  1153 INCOMPATIBILITY.
  1154 
  1155 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  1156 more efficient than combinations with -q1 or -q2.
  1157 
  1158 
  1159 *** Pure ***
  1160 
  1161 * Proofterms record type-class reasoning explicitly, using the
  1162 "unconstrain" operation internally.  This eliminates all sort
  1163 constraints from a theorem and proof, introducing explicit
  1164 OFCLASS-premises.  On the proof term level, this operation is
  1165 automatically applied at theorem boundaries, such that closed proofs
  1166 are always free of sort constraints.  INCOMPATIBILITY for tools that
  1167 inspect proof terms.
  1168 
  1169 * Local theory specifications may depend on extra type variables that
  1170 are not present in the result type -- arguments TYPE('a) :: 'a itself
  1171 are added internally.  For example:
  1172 
  1173   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  1174 
  1175 * Predicates of locales introduced by classes carry a mandatory
  1176 "class" prefix.  INCOMPATIBILITY.
  1177 
  1178 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  1179 
  1180 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  1181 'class' instead.
  1182 
  1183 * Command 'code_reflect' allows to incorporate generated ML code into
  1184 runtime environment; replaces immature code_datatype antiquotation.
  1185 INCOMPATIBILITY.
  1186 
  1187 * Code generator: simple concept for abstract datatypes obeying
  1188 invariants.
  1189 
  1190 * Code generator: details of internal data cache have no impact on the
  1191 user space functionality any longer.
  1192 
  1193 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1194 subgoals.  This is more appropriate for interpretations with 'where'.
  1195 INCOMPATIBILITY.
  1196 
  1197 * Command 'example_proof' opens an empty proof body.  This allows to
  1198 experiment with Isar, without producing any persistent result.
  1199 
  1200 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1201 within a local theory context, with explicit checking of the
  1202 constructors involved (in contrast to the raw 'syntax' versions).
  1203 
  1204 * Commands 'types' and 'typedecl' now work within a local theory
  1205 context -- without introducing dependencies on parameters or
  1206 assumptions, which is not possible in Isabelle/Pure.
  1207 
  1208 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1209 within a local theory context.  Minor INCOMPATIBILITY.
  1210 
  1211 
  1212 *** HOL ***
  1213 
  1214 * Command 'typedef' now works within a local theory context -- without
  1215 introducing dependencies on parameters or assumptions, which is not
  1216 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1217 contain multiple interpretations of local typedefs (with different
  1218 non-emptiness proofs), even in a global theory context.
  1219 
  1220 * New package for quotient types.  Commands 'quotient_type' and
  1221 'quotient_definition' may be used for defining types and constants by
  1222 quotient constructions.  An example is the type of integers created by
  1223 quotienting pairs of natural numbers:
  1224 
  1225   fun
  1226     intrel :: "(nat * nat) => (nat * nat) => bool"
  1227   where
  1228     "intrel (x, y) (u, v) = (x + v = u + y)"
  1229 
  1230   quotient_type int = "nat * nat" / intrel
  1231     by (auto simp add: equivp_def expand_fun_eq)
  1232 
  1233   quotient_definition
  1234     "0::int" is "(0::nat, 0::nat)"
  1235 
  1236 The method "lifting" can be used to lift of theorems from the
  1237 underlying "raw" type to the quotient type.  The example
  1238 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1239 construction and provides a reasoning infrastructure for finite sets.
  1240 
  1241 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1242 clash with new theory Quotient in Main HOL.
  1243 
  1244 * Moved the SMT binding into the main HOL session, eliminating
  1245 separate HOL-SMT session.
  1246 
  1247 * List membership infix mem operation is only an input abbreviation.
  1248 INCOMPATIBILITY.
  1249 
  1250 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1251 for future developements; former Library/Word.thy is still present in
  1252 the AFP entry RSAPPS.
  1253 
  1254 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1255 longer shadowed.  INCOMPATIBILITY.
  1256 
  1257 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1258 INCOMPATIBILITY.
  1259 
  1260 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1261 INCOMPATIBILITY.
  1262 
  1263 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1264 instead.  INCOMPATIBILITY.
  1265 
  1266 * Dropped several real-specific versions of lemmas about floor and
  1267 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1268 instead.  INCOMPATIBILITY.
  1269 
  1270   floor_number_of_eq         ~> floor_number_of
  1271   le_floor_eq_number_of      ~> number_of_le_floor
  1272   le_floor_eq_zero           ~> zero_le_floor
  1273   le_floor_eq_one            ~> one_le_floor
  1274   floor_less_eq_number_of    ~> floor_less_number_of
  1275   floor_less_eq_zero         ~> floor_less_zero
  1276   floor_less_eq_one          ~> floor_less_one
  1277   less_floor_eq_number_of    ~> number_of_less_floor
  1278   less_floor_eq_zero         ~> zero_less_floor
  1279   less_floor_eq_one          ~> one_less_floor
  1280   floor_le_eq_number_of      ~> floor_le_number_of
  1281   floor_le_eq_zero           ~> floor_le_zero
  1282   floor_le_eq_one            ~> floor_le_one
  1283   floor_subtract_number_of   ~> floor_diff_number_of
  1284   floor_subtract_one         ~> floor_diff_one
  1285   ceiling_number_of_eq       ~> ceiling_number_of
  1286   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1287   ceiling_le_zero_eq         ~> ceiling_le_zero
  1288   ceiling_le_eq_one          ~> ceiling_le_one
  1289   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1290   less_ceiling_eq_zero       ~> zero_less_ceiling
  1291   less_ceiling_eq_one        ~> one_less_ceiling
  1292   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1293   ceiling_less_eq_zero       ~> ceiling_less_zero
  1294   ceiling_less_eq_one        ~> ceiling_less_one
  1295   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1296   le_ceiling_eq_zero         ~> zero_le_ceiling
  1297   le_ceiling_eq_one          ~> one_le_ceiling
  1298   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1299   ceiling_subtract_one       ~> ceiling_diff_one
  1300 
  1301 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1302 application of the various fold combinators on finite sets.
  1303 
  1304 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1305 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1306 implementation.  INCOMPATIBILTY.
  1307 
  1308 * Theory Library/Coinductive_List has been removed -- superseded by
  1309 AFP/thys/Coinductive.
  1310 
  1311 * Theory PReal, including the type "preal" and related operations, has
  1312 been removed.  INCOMPATIBILITY.
  1313 
  1314 * Real: new development using Cauchy Sequences.
  1315 
  1316 * Split off theory "Big_Operators" containing setsum, setprod,
  1317 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1318 
  1319 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1320 "Int" etc.  INCOMPATIBILITY.
  1321 
  1322 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1323 
  1324 * New set of rules "ac_simps" provides combined assoc / commute
  1325 rewrites for all interpretations of the appropriate generic locales.
  1326 
  1327 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1328 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1329 appropriate and more consistent names suitable for name prefixes
  1330 within the HOL theories.  INCOMPATIBILITY.
  1331 
  1332 * Some generic constants have been put to appropriate theories:
  1333   - less_eq, less: Orderings
  1334   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1335   - inverse, divide: Rings
  1336 INCOMPATIBILITY.
  1337 
  1338 * More consistent naming of type classes involving orderings (and
  1339 lattices):
  1340 
  1341     lower_semilattice                   ~> semilattice_inf
  1342     upper_semilattice                   ~> semilattice_sup
  1343 
  1344     dense_linear_order                  ~> dense_linorder
  1345 
  1346     pordered_ab_group_add               ~> ordered_ab_group_add
  1347     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1348     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1349     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1350     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1351     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1352     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1353     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1354     pordered_comm_ring                  ~> ordered_comm_ring
  1355     pordered_comm_semiring              ~> ordered_comm_semiring
  1356     pordered_ring                       ~> ordered_ring
  1357     pordered_ring_abs                   ~> ordered_ring_abs
  1358     pordered_semiring                   ~> ordered_semiring
  1359 
  1360     ordered_ab_group_add                ~> linordered_ab_group_add
  1361     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1362     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1363     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1364     ordered_field                       ~> linordered_field
  1365     ordered_field_no_lb                 ~> linordered_field_no_lb
  1366     ordered_field_no_ub                 ~> linordered_field_no_ub
  1367     ordered_field_dense_linear_order    ~> dense_linordered_field
  1368     ordered_idom                        ~> linordered_idom
  1369     ordered_ring                        ~> linordered_ring
  1370     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1371     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1372     ordered_ring_strict                 ~> linordered_ring_strict
  1373     ordered_semidom                     ~> linordered_semidom
  1374     ordered_semiring                    ~> linordered_semiring
  1375     ordered_semiring_1                  ~> linordered_semiring_1
  1376     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1377     ordered_semiring_strict             ~> linordered_semiring_strict
  1378 
  1379   The following slightly odd type classes have been moved to a
  1380   separate theory Library/Lattice_Algebras:
  1381 
  1382     lordered_ab_group_add               ~> lattice_ab_group_add
  1383     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1384     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1385     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1386     lordered_ring                       ~> lattice_ring
  1387 
  1388 INCOMPATIBILITY.
  1389 
  1390 * Refined field classes:
  1391   - classes division_ring_inverse_zero, field_inverse_zero,
  1392     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1393     subsumes former division_by_zero class;
  1394   - numerous lemmas have been ported from field to division_ring.
  1395 INCOMPATIBILITY.
  1396 
  1397 * Refined algebra theorem collections:
  1398   - dropped theorem group group_simps, use algebra_simps instead;
  1399   - dropped theorem group ring_simps, use field_simps instead;
  1400   - proper theorem collection field_simps subsumes former theorem
  1401     groups field_eq_simps and field_simps;
  1402   - dropped lemma eq_minus_self_iff which is a duplicate for
  1403     equal_neg_zero.
  1404 INCOMPATIBILITY.
  1405 
  1406 * Theory Finite_Set and List: some lemmas have been generalized from
  1407 sets to lattices:
  1408 
  1409   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1410   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1411   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1412   union_Union_fold_union        ~> sup_Sup_fold_sup
  1413   Inter_fold_inter              ~> Inf_fold_inf
  1414   Union_fold_union              ~> Sup_fold_sup
  1415   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1416   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1417   INTER_fold_inter              ~> INFI_fold_inf
  1418   UNION_fold_union              ~> SUPR_fold_sup
  1419 
  1420 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1421 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1422 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1423 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1424 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1425 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1426 
  1427 * Reorganized theory Multiset: swapped notation of pointwise and
  1428 multiset order:
  1429 
  1430   - pointwise ordering is instance of class order with standard syntax
  1431     <= and <;
  1432   - multiset ordering has syntax <=# and <#; partial order properties
  1433     are provided by means of interpretation with prefix
  1434     multiset_order;
  1435   - less duplication, less historical organization of sections,
  1436     conversion from associations lists to multisets, rudimentary code
  1437     generation;
  1438   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1439     if needed.
  1440 
  1441 Renamed:
  1442 
  1443   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1444   multi_count_ext  ~>  multiset_ext
  1445   diff_union_inverse2  ~>  diff_union_cancelR
  1446 
  1447 INCOMPATIBILITY.
  1448 
  1449 * Theory Permutation: replaced local "remove" by List.remove1.
  1450 
  1451 * Code generation: ML and OCaml code is decorated with signatures.
  1452 
  1453 * Theory List: added transpose.
  1454 
  1455 * Library/Nat_Bijection.thy is a collection of bijective functions
  1456 between nat and other types, which supersedes the older libraries
  1457 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1458 
  1459   Constants:
  1460   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1461   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1462   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1463   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1464   Countable.pair_encode           ~> prod_encode
  1465   NatIso.prod2nat                 ~> prod_encode
  1466   NatIso.nat2prod                 ~> prod_decode
  1467   NatIso.sum2nat                  ~> sum_encode
  1468   NatIso.nat2sum                  ~> sum_decode
  1469   NatIso.list2nat                 ~> list_encode
  1470   NatIso.nat2list                 ~> list_decode
  1471   NatIso.set2nat                  ~> set_encode
  1472   NatIso.nat2set                  ~> set_decode
  1473 
  1474   Lemmas:
  1475   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1476   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1477   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1478   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1479   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1480   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1481   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1482   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1483   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1484   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1485   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1486   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1487   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1488 
  1489 * Sledgehammer:
  1490   - Renamed ATP commands:
  1491     atp_info     ~> sledgehammer running_atps
  1492     atp_kill     ~> sledgehammer kill_atps
  1493     atp_messages ~> sledgehammer messages
  1494     atp_minimize ~> sledgehammer minimize
  1495     print_atps   ~> sledgehammer available_atps
  1496     INCOMPATIBILITY.
  1497   - Added user's manual ("isabelle doc sledgehammer").
  1498   - Added option syntax and "sledgehammer_params" to customize
  1499     Sledgehammer's behavior.  See the manual for details.
  1500   - Modified the Isar proof reconstruction code so that it produces
  1501     direct proofs rather than proofs by contradiction.  (This feature
  1502     is still experimental.)
  1503   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1504     full-typed mode.
  1505   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1506 
  1507 * Nitpick:
  1508   - Added and implemented "binary_ints" and "bits" options.
  1509   - Added "std" option and implemented support for nonstandard models.
  1510   - Added and implemented "finitize" option to improve the precision
  1511     of infinite datatypes based on a monotonicity analysis.
  1512   - Added support for quotient types.
  1513   - Added support for "specification" and "ax_specification"
  1514     constructs.
  1515   - Added support for local definitions (for "function" and
  1516     "termination" proofs).
  1517   - Added support for term postprocessors.
  1518   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1519   - Improved efficiency of "destroy_constrs" optimization.
  1520   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1521     record getters.
  1522   - Fixed soundness bug related to higher-order constructors.
  1523   - Fixed soundness bug when "full_descrs" is enabled.
  1524   - Improved precision of set constructs.
  1525   - Added "atoms" option.
  1526   - Added cache to speed up repeated Kodkod invocations on the same
  1527     problems.
  1528   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1529     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1530     "SAT4J_Light".  INCOMPATIBILITY.
  1531   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1532     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1533   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1534 
  1535 * Method "induct" now takes instantiations of the form t, where t is not
  1536   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1537   If this is not intended, t has to be enclosed in parentheses.
  1538   By default, the equalities generated by definitional instantiations
  1539   are pre-simplified, which may cause parameters of inductive cases
  1540   to disappear, or may even delete some of the inductive cases.
  1541   Use "induct (no_simp)" instead of "induct" to restore the old
  1542   behaviour. The (no_simp) option is also understood by the "cases"
  1543   and "nominal_induct" methods, which now perform pre-simplification, too.
  1544   INCOMPATIBILITY.
  1545 
  1546 
  1547 *** HOLCF ***
  1548 
  1549 * Variable names in lemmas generated by the domain package have
  1550 changed; the naming scheme is now consistent with the HOL datatype
  1551 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1552 
  1553 * The domain package no longer defines the function "foo_copy" for
  1554 recursive domain "foo".  The reach lemma is now stated directly in
  1555 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1556 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1557 
  1558 * Most definedness lemmas generated by the domain package (previously
  1559 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1560 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1561 Proofs that used definedness lemmas as intro rules may break,
  1562 potential INCOMPATIBILITY.
  1563 
  1564 * Induction and casedist rules generated by the domain package now
  1565 declare proper case_names (one called "bottom", and one named for each
  1566 constructor).  INCOMPATIBILITY.
  1567 
  1568 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1569 rules are generated for each domain, INCOMPATIBILITY.
  1570 
  1571   foo_bar.reach       ~> foo.reach  bar.reach
  1572   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1573 
  1574 * Some lemmas generated by the domain package have been renamed for
  1575 consistency with the datatype package, INCOMPATIBILITY.
  1576 
  1577   foo.ind        ~> foo.induct
  1578   foo.finite_ind ~> foo.finite_induct
  1579   foo.coind      ~> foo.coinduct
  1580   foo.casedist   ~> foo.exhaust
  1581   foo.exhaust    ~> foo.nchotomy
  1582 
  1583 * For consistency with other definition packages, the fixrec package
  1584 now generates qualified theorem names, INCOMPATIBILITY.
  1585 
  1586   foo_simps  ~> foo.simps
  1587   foo_unfold ~> foo.unfold
  1588   foo_induct ~> foo.induct
  1589 
  1590 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1591 method and internal fixrec proofs now use the default simpset instead.
  1592 INCOMPATIBILITY.
  1593 
  1594 * The "contlub" predicate has been removed.  Proof scripts should use
  1595 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1596 
  1597 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1598 
  1599 * The constants cpair, cfst, and csnd have been removed in favor of
  1600 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1601 
  1602 
  1603 *** ML ***
  1604 
  1605 * Antiquotations for basic formal entities:
  1606 
  1607     @{class NAME}         -- type class
  1608     @{class_syntax NAME}  -- syntax representation of the above
  1609 
  1610     @{type_name NAME}     -- logical type
  1611     @{type_abbrev NAME}   -- type abbreviation
  1612     @{nonterminal NAME}   -- type of concrete syntactic category
  1613     @{type_syntax NAME}   -- syntax representation of any of the above
  1614 
  1615     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1616     @{const_abbrev NAME}  -- abbreviated constant
  1617     @{const_syntax NAME}  -- syntax representation of any of the above
  1618 
  1619 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1620 syntax constant (cf. 'syntax' command).
  1621 
  1622 * Antiquotation @{make_string} inlines a function to print arbitrary
  1623 values similar to the ML toplevel.  The result is compiler dependent
  1624 and may fall back on "?" in certain situations.
  1625 
  1626 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1627 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1628 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1629 not work with the asynchronous Isar document model.
  1630 
  1631 * Configuration options now admit dynamic default values, depending on
  1632 the context or even global references.
  1633 
  1634 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1635 uses an efficient external library if available (for Poly/ML).
  1636 
  1637 * Renamed some important ML structures, while keeping the old names
  1638 for some time as aliases within the structure Legacy:
  1639 
  1640   OuterKeyword  ~>  Keyword
  1641   OuterLex      ~>  Token
  1642   OuterParse    ~>  Parse
  1643   OuterSyntax   ~>  Outer_Syntax
  1644   PrintMode     ~>  Print_Mode
  1645   SpecParse     ~>  Parse_Spec
  1646   ThyInfo       ~>  Thy_Info
  1647   ThyLoad       ~>  Thy_Load
  1648   ThyOutput     ~>  Thy_Output
  1649   TypeInfer     ~>  Type_Infer
  1650 
  1651 Note that "open Legacy" simplifies porting of sources, but forgetting
  1652 to remove it again will complicate porting again in the future.
  1653 
  1654 * Most operations that refer to a global context are named
  1655 accordingly, e.g. Simplifier.global_context or
  1656 ProofContext.init_global.  There are some situations where a global
  1657 context actually works, but under normal circumstances one needs to
  1658 pass the proper local context through the code!
  1659 
  1660 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1661 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1662 Pretty.pp argument to merge, which is absent in the standard
  1663 Theory_Data version.
  1664 
  1665 * Sorts.certify_sort and derived "cert" operations for types and terms
  1666 no longer minimize sorts.  Thus certification at the boundary of the
  1667 inference kernel becomes invariant under addition of class relations,
  1668 which is an important monotonicity principle.  Sorts are now minimized
  1669 in the syntax layer only, at the boundary between the end-user and the
  1670 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1671 explicitly in rare situations.
  1672 
  1673 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1674 emphasize that this is in no way a standard operation.
  1675 INCOMPATIBILITY.
  1676 
  1677 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1678 usual for resolution.  Rare INCOMPATIBILITY.
  1679 
  1680 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1681 to emphasize that these only work in a global situation (which is
  1682 quite rare).
  1683 
  1684 * Curried take and drop in library.ML; negative length is interpreted
  1685 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1686 
  1687 * Proof terms: type substitutions on proof constants now use canonical
  1688 order of type variables.  INCOMPATIBILITY for tools working with proof
  1689 terms.
  1690 
  1691 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1692 may no longer carry premises.  User-level specifications are
  1693 transformed accordingly by Thm.add_axiom/add_def.
  1694 
  1695 
  1696 *** System ***
  1697 
  1698 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1699 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1700 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1701 
  1702 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1703 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1704 respectively.
  1705 
  1706 * Old lib/scripts/polyml-platform is superseded by the
  1707 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1708 variant, even on a 64 bit machine.  The following example setting
  1709 prefers 64 bit if available:
  1710 
  1711   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1712 
  1713 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1714 Isabelle/Scala layer for advanced prover interaction and integration.
  1715 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1716 component.
  1717 
  1718 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1719 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1720 similar to the default assignment of the document preparation system
  1721 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1722 provides some operations for direct access to the font without asking
  1723 the user for manual installation.
  1724 
  1725 
  1726 
  1727 New in Isabelle2009-1 (December 2009)
  1728 -------------------------------------
  1729 
  1730 *** General ***
  1731 
  1732 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1733 one backslash should be used, even in ML sources.
  1734 
  1735 
  1736 *** Pure ***
  1737 
  1738 * Locale interpretation propagates mixins along the locale hierarchy.
  1739 The currently only available mixins are the equations used to map
  1740 local definitions to terms of the target domain of an interpretation.
  1741 
  1742 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1743 loc" to print all interpretations of locale "loc" in the theory.
  1744 Interpretations in proofs are not shown.
  1745 
  1746 * Thoroughly revised locales tutorial.  New section on conditional
  1747 interpretation.
  1748 
  1749 * On instantiation of classes, remaining undefined class parameters
  1750 are formally declared.  INCOMPATIBILITY.
  1751 
  1752 
  1753 *** Document preparation ***
  1754 
  1755 * New generalized style concept for printing terms: @{foo (style) ...}
  1756 instead of @{foo_style style ...}  (old form is still retained for
  1757 backward compatibility).  Styles can be also applied for
  1758 antiquotations prop, term_type and typeof.
  1759 
  1760 
  1761 *** HOL ***
  1762 
  1763 * New proof method "smt" for a combination of first-order logic with
  1764 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1765 fixed-size bitvectors; there is also basic support for higher-order
  1766 features (esp. lambda abstractions).  It is an incomplete decision
  1767 procedure based on external SMT solvers using the oracle mechanism;
  1768 for the SMT solver Z3, this method is proof-producing.  Certificates
  1769 are provided to avoid calling the external solvers solely for
  1770 re-checking proofs.  Due to a remote SMT service there is no need for
  1771 installing SMT solvers locally.  See src/HOL/SMT.
  1772 
  1773 * New commands to load and prove verification conditions generated by
  1774 the Boogie program verifier or derived systems (e.g. the Verifying C
  1775 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1776 
  1777 * New counterexample generator tool 'nitpick' based on the Kodkod
  1778 relational model finder.  See src/HOL/Tools/Nitpick and
  1779 src/HOL/Nitpick_Examples.
  1780 
  1781 * New commands 'code_pred' and 'values' to invoke the predicate
  1782 compiler and to enumerate values of inductive predicates.
  1783 
  1784 * A tabled implementation of the reflexive transitive closure.
  1785 
  1786 * New implementation of quickcheck uses generic code generator;
  1787 default generators are provided for all suitable HOL types, records
  1788 and datatypes.  Old quickcheck can be re-activated importing theory
  1789 Library/SML_Quickcheck.
  1790 
  1791 * New testing tool Mirabelle for automated proof tools.  Applies
  1792 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1793 every proof step in a theory.  To be used in batch mode via the
  1794 "mirabelle" utility.
  1795 
  1796 * New proof method "sos" (sum of squares) for nonlinear real
  1797 arithmetic (originally due to John Harison). It requires theory
  1798 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1799 works well in practice on quantifier-free real arithmetic with +, -,
  1800 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1801 inequalities between polynomials.  It makes use of external
  1802 semidefinite programming solvers.  Method "sos" generates a
  1803 certificate that can be pasted into the proof thus avoiding the need
  1804 to call an external tool every time the proof is checked.  See
  1805 src/HOL/Library/Sum_Of_Squares.
  1806 
  1807 * New method "linarith" invokes existing linear arithmetic decision
  1808 procedure only.
  1809 
  1810 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1811 
  1812 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1813 Causes full type information to be output to the ATPs.  This slows
  1814 ATPs down considerably but eliminates a source of unsound "proofs"
  1815 that fail later.
  1816 
  1817 * New method "metisFT": A version of metis that uses full type
  1818 information in order to avoid failures of proof reconstruction.
  1819 
  1820 * New evaluator "approximate" approximates an real valued term using
  1821 the same method as the approximation method.
  1822 
  1823 * Method "approximate" now supports arithmetic expressions as
  1824 boundaries of intervals and implements interval splitting and Taylor
  1825 series expansion.
  1826 
  1827 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1828 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1829 
  1830 * New theory SupInf of the supremum and infimum operators for sets of
  1831 reals.
  1832 
  1833 * New theory Probability, which contains a development of measure
  1834 theory, eventually leading to Lebesgue integration and probability.
  1835 
  1836 * Extended Multivariate Analysis to include derivation and Brouwer's
  1837 fixpoint theorem.
  1838 
  1839 * Reorganization of number theory, INCOMPATIBILITY:
  1840   - new number theory development for nat and int, in theories Divides
  1841     and GCD as well as in new session Number_Theory
  1842   - some constants and facts now suffixed with _nat and _int
  1843     accordingly
  1844   - former session NumberTheory now named Old_Number_Theory, including
  1845     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1846   - moved theory Pocklington from src/HOL/Library to
  1847     src/HOL/Old_Number_Theory
  1848 
  1849 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1850 lcm of finite and infinite sets. It is shown that they form a complete
  1851 lattice.
  1852 
  1853 * Class semiring_div requires superclass no_zero_divisors and proof of
  1854 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1855 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1856 generalized to class semiring_div, subsuming former theorems
  1857 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1858 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1859 INCOMPATIBILITY.
  1860 
  1861 * Refinements to lattice classes and sets:
  1862   - less default intro/elim rules in locale variant, more default
  1863     intro/elim rules in class variant: more uniformity
  1864   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1865     le_inf_iff
  1866   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1867     sup_aci)
  1868   - renamed ACI to inf_sup_aci
  1869   - new class "boolean_algebra"
  1870   - class "complete_lattice" moved to separate theory
  1871     "Complete_Lattice"; corresponding constants (and abbreviations)
  1872     renamed and with authentic syntax:
  1873     Set.Inf ~>    Complete_Lattice.Inf
  1874     Set.Sup ~>    Complete_Lattice.Sup
  1875     Set.INFI ~>   Complete_Lattice.INFI
  1876     Set.SUPR ~>   Complete_Lattice.SUPR
  1877     Set.Inter ~>  Complete_Lattice.Inter
  1878     Set.Union ~>  Complete_Lattice.Union
  1879     Set.INTER ~>  Complete_Lattice.INTER
  1880     Set.UNION ~>  Complete_Lattice.UNION
  1881   - authentic syntax for
  1882     Set.Pow
  1883     Set.image
  1884   - mere abbreviations:
  1885     Set.empty               (for bot)
  1886     Set.UNIV                (for top)
  1887     Set.inter               (for inf, formerly Set.Int)
  1888     Set.union               (for sup, formerly Set.Un)
  1889     Complete_Lattice.Inter  (for Inf)
  1890     Complete_Lattice.Union  (for Sup)
  1891     Complete_Lattice.INTER  (for INFI)
  1892     Complete_Lattice.UNION  (for SUPR)
  1893   - object-logic definitions as far as appropriate
  1894 
  1895 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1896 Un_subset_iff are explicitly deleted as default simp rules; then also
  1897 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1898 deleted to achieve the desired effect.
  1899 
  1900 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1901 rules by default any longer; the same applies to min_max.inf_absorb1
  1902 etc.  INCOMPATIBILITY.
  1903 
  1904 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1905 pred_set_conv by default.  INCOMPATIBILITY.
  1906 
  1907 * Power operations on relations and functions are now one dedicated
  1908 constant "compow" with infix syntax "^^".  Power operation on
  1909 multiplicative monoids retains syntax "^" and is now defined generic
  1910 in class power.  INCOMPATIBILITY.
  1911 
  1912 * Relation composition "R O S" now has a more standard argument order:
  1913 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1914 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1915 break, since the O_assoc rule was not rewritten like this.  Fix using
  1916 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1917 
  1918 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1919 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1920 INCOMPATIBILITY.
  1921 
  1922 * Most rules produced by inductive and datatype package have mandatory
  1923 prefixes.  INCOMPATIBILITY.
  1924 
  1925 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1926 the attribute of the same name.  Each of the theorems in the list
  1927 DERIV_intros assumes composition with an additional function and
  1928 matches a variable to the derivative, which has to be solved by the
  1929 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1930 of most elementary terms.  Former Maclauren.DERIV_tac and
  1931 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1932 INCOMPATIBILITY.
  1933 
  1934 * Code generator attributes follow the usual underscore convention:
  1935     code_unfold     replaces    code unfold
  1936     code_post       replaces    code post
  1937     etc.
  1938   INCOMPATIBILITY.
  1939 
  1940 * Renamed methods:
  1941     sizechange -> size_change
  1942     induct_scheme -> induction_schema
  1943   INCOMPATIBILITY.
  1944 
  1945 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1946 INCOMPATIBILITY, use "undefined" directly.
  1947 
  1948 * Renamed theorems:
  1949     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1950     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1951     Suc_plus1 -> Suc_eq_plus1
  1952     *anti_sym -> *antisym*
  1953     vector_less_eq_def -> vector_le_def
  1954   INCOMPATIBILITY.
  1955 
  1956 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1957 INCOMPATIBILITY.
  1958 
  1959 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1960 INCOMPATIBILITY.
  1961 
  1962 
  1963 *** HOLCF ***
  1964 
  1965 * Theory Representable defines a class "rep" of domains that are
  1966 representable (via an ep-pair) in the universal domain type "udom".
  1967 Instances are provided for all type constructors defined in HOLCF.
  1968 
  1969 * The 'new_domain' command is a purely definitional version of the
  1970 domain package, for representable domains.  Syntax is identical to the
  1971 old domain package.  The 'new_domain' package also supports indirect
  1972 recursion using previously-defined type constructors.  See
  1973 src/HOLCF/ex/New_Domain.thy for examples.
  1974 
  1975 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1976 on the left-hand side of an equation, and then performs
  1977 simplification.  Rewriting is done using rules declared with the
  1978 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1979 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1980 
  1981 * The pattern-match compiler in 'fixrec' can now handle constructors
  1982 with HOL function types.  Pattern-match combinators for the Pair
  1983 constructor are pre-configured.
  1984 
  1985 * The 'fixrec' package now produces better fixed-point induction rules
  1986 for mutually-recursive definitions:  Induction rules have conclusions
  1987 of the form "P foo bar" instead of "P <foo, bar>".
  1988 
  1989 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1990 been renamed to "below".  The name "below" now replaces "less" in many
  1991 theorem names.  (Legacy theorem names using "less" are still supported
  1992 as well.)
  1993 
  1994 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1995 patterns can be used to generate strictness rules, or to make
  1996 functions more strict (much like the bang-patterns supported by the
  1997 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1998 examples.
  1999 
  2000 
  2001 *** ML ***
  2002 
  2003 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  2004 errors and run-time exceptions, including detailed source positions.
  2005 
  2006 * Structure Name_Space (formerly NameSpace) now manages uniquely
  2007 identified entries, with some additional information such as source
  2008 position, logical grouping etc.
  2009 
  2010 * Theory and context data is now introduced by the simplified and
  2011 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  2012 to be pure, but the old TheoryDataFun for mutable data (with explicit
  2013 copy operation) is still available for some time.
  2014 
  2015 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  2016 provides a high-level programming interface to synchronized state
  2017 variables with atomic update.  This works via pure function
  2018 application within a critical section -- its runtime should be as
  2019 short as possible; beware of deadlocks if critical code is nested,
  2020 either directly or indirectly via other synchronized variables!
  2021 
  2022 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  2023 wraps raw ML references, explicitly indicating their non-thread-safe
  2024 behaviour.  The Isar toplevel keeps this structure open, to
  2025 accommodate Proof General as well as quick and dirty interactive
  2026 experiments with references.
  2027 
  2028 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  2029 parallel tactical reasoning.
  2030 
  2031 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  2032 are similar to SUBPROOF, but are slightly more flexible: only the
  2033 specified parts of the subgoal are imported into the context, and the
  2034 body tactic may introduce new subgoals and schematic variables.
  2035 
  2036 * Old tactical METAHYPS, which does not observe the proof context, has
  2037 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  2038 or Subgoal.FOCUS etc.
  2039 
  2040 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  2041 functors have their own ML name space there is no point to mark them
  2042 separately.)  Minor INCOMPATIBILITY.
  2043 
  2044 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  2045 
  2046 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  2047 INCOMPATIBILITY.
  2048 
  2049 * Operations of structure Skip_Proof no longer require quick_and_dirty
  2050 mode, which avoids critical setmp.
  2051 
  2052 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  2053 combinators for "args".  INCOMPATIBILITY, need to use simplified
  2054 Attrib/Method.setup introduced in Isabelle2009.
  2055 
  2056 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  2057 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  2058 last resort.  INCOMPATIBILITY.
  2059 
  2060 * Display.pretty_thm now requires a proper context (cf. former
  2061 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  2062 or even Display.pretty_thm_without_context as last resort.
  2063 INCOMPATIBILITY.
  2064 
  2065 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  2066 Syntax.pretty_typ/term directly, preferably with proper context
  2067 instead of global theory.
  2068 
  2069 
  2070 *** System ***
  2071 
  2072 * Further fine tuning of parallel proof checking, scales up to 8 cores
  2073 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  2074 usedir option -q.
  2075 
  2076 * Support for additional "Isabelle components" via etc/components, see
  2077 also the system manual.
  2078 
  2079 * The isabelle makeall tool now operates on all components with
  2080 IsaMakefile, not just hardwired "logics".
  2081 
  2082 * Removed "compress" option from isabelle-process and isabelle usedir;
  2083 this is always enabled.
  2084 
  2085 * Discontinued support for Poly/ML 4.x versions.
  2086 
  2087 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  2088 on a given logic image.  This requires the lighttpd webserver and is
  2089 currently supported on Linux only.
  2090 
  2091 
  2092 
  2093 New in Isabelle2009 (April 2009)
  2094 --------------------------------
  2095 
  2096 *** General ***
  2097 
  2098 * Simplified main Isabelle executables, with less surprises on
  2099 case-insensitive file-systems (such as Mac OS).
  2100 
  2101   - The main Isabelle tool wrapper is now called "isabelle" instead of
  2102     "isatool."
  2103 
  2104   - The former "isabelle" alias for "isabelle-process" has been
  2105     removed (should rarely occur to regular users).
  2106 
  2107   - The former "isabelle-interface" and its alias "Isabelle" have been
  2108     removed (interfaces are now regular Isabelle tools).
  2109 
  2110 Within scripts and make files, the Isabelle environment variables
  2111 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  2112 respectively.  (The latter are still available as legacy feature.)
  2113 
  2114 The old isabelle-interface wrapper could react in confusing ways if
  2115 the interface was uninstalled or changed otherwise.  Individual
  2116 interface tool configuration is now more explicit, see also the
  2117 Isabelle system manual.  In particular, Proof General is now available
  2118 via "isabelle emacs".
  2119 
  2120 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  2121 purge installed copies of Isabelle executables and re-run "isabelle
  2122 install -p ...", or use symlinks.
  2123 
  2124 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  2125 old ~/isabelle, which was slightly non-standard and apt to cause
  2126 surprises on case-insensitive file-systems (such as Mac OS).
  2127 
  2128 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  2129 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  2130 care is required when using older releases of Isabelle.  Note that
  2131 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  2132 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  2133 
  2134 * Proofs of fully specified statements are run in parallel on
  2135 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  2136 a regular 4-core machine, if the initial heap space is made reasonably
  2137 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  2138 
  2139 * The main reference manuals ("isar-ref", "implementation", and
  2140 "system") have been updated and extended.  Formally checked references
  2141 as hyperlinks are now available uniformly.
  2142 
  2143 
  2144 *** Pure ***
  2145 
  2146 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  2147 respects.  The most important changes are listed below.  See the
  2148 Tutorial on Locales ("locales" manual) for details.
  2149 
  2150 - In locale expressions, instantiation replaces renaming.  Parameters
  2151 must be declared in a for clause.  To aid compatibility with previous
  2152 parameter inheritance, in locale declarations, parameters that are not
  2153 'touched' (instantiation position "_" or omitted) are implicitly added
  2154 with their syntax at the beginning of the for clause.
  2155 
  2156 - Syntax from abbreviations and definitions in locales is available in
  2157 locale expressions and context elements.  The latter is particularly
  2158 useful in locale declarations.
  2159 
  2160 - More flexible mechanisms to qualify names generated by locale
  2161 expressions.  Qualifiers (prefixes) may be specified in locale
  2162 expressions, and can be marked as mandatory (syntax: "name!:") or
  2163 optional (syntax "name?:").  The default depends for plain "name:"
  2164 depends on the situation where a locale expression is used: in
  2165 commands 'locale' and 'sublocale' prefixes are optional, in
  2166 'interpretation' and 'interpret' prefixes are mandatory.  The old
  2167 implicit qualifiers derived from the parameter names of a locale are
  2168 no longer generated.
  2169 
  2170 - Command "sublocale l < e" replaces "interpretation l < e".  The
  2171 instantiation clause in "interpretation" and "interpret" (square
  2172 brackets) is no longer available.  Use locale expressions.
  2173 
  2174 - When converting proof scripts, mandatory qualifiers in
  2175 'interpretation' and 'interpret' should be retained by default, even
  2176 if this is an INCOMPATIBILITY compared to former behavior.  In the
  2177 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  2178 in locale expressions range over a single locale instance only.
  2179 
  2180 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  2181 In existing theorem specifications replace the includes element by the
  2182 respective context elements of the included locale, omitting those
  2183 that are already present in the theorem specification.  Multiple
  2184 assume elements of a locale should be replaced by a single one
  2185 involving the locale predicate.  In the proof body, declarations (most
  2186 notably theorems) may be regained by interpreting the respective
  2187 locales in the proof context as required (command "interpret").
  2188 
  2189 If using "includes" in replacement of a target solely because the
  2190 parameter types in the theorem are not as general as in the target,
  2191 consider declaring a new locale with additional type constraints on
  2192 the parameters (context element "constrains").
  2193 
  2194 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2195 
  2196 - Locale interpretation commands no longer attempt to simplify goal.
  2197 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2198 methods intro_locales and unfold_locales to clarify.
  2199 
  2200 - Locale interpretation commands no longer accept interpretation
  2201 attributes.  INCOMPATIBILITY.
  2202 
  2203 * Class declaration: so-called "base sort" must not be given in import
  2204 list any longer, but is inferred from the specification.  Particularly
  2205 in HOL, write
  2206 
  2207     class foo = ...
  2208 
  2209 instead of
  2210 
  2211     class foo = type + ...
  2212 
  2213 * Class target: global versions of theorems stemming do not carry a
  2214 parameter prefix any longer.  INCOMPATIBILITY.
  2215 
  2216 * Class 'instance' command no longer accepts attached definitions.
  2217 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2218 
  2219 * Recovered hiding of consts, which was accidentally broken in
  2220 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2221 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2222 
  2223 * Slightly more coherent Pure syntax, with updated documentation in
  2224 isar-ref manual.  Removed locales meta_term_syntax and
  2225 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2226 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2227 directly in regular applications.
  2228 
  2229 * There is a new syntactic category "float_const" for signed decimal
  2230 fractions (e.g. 123.45 or -123.45).
  2231 
  2232 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2233 interface with 'setup' command instead.
  2234 
  2235 * Command 'local_setup' is similar to 'setup', but operates on a local
  2236 theory context.
  2237 
  2238 * The 'axiomatization' command now only works within a global theory
  2239 context.  INCOMPATIBILITY.
  2240 
  2241 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2242 hypotheses.  Sorts required in the course of reasoning need to be
  2243 covered by the constraints in the initial statement, completed by the
  2244 type instance information of the background theory.  Non-trivial sort
  2245 hypotheses, which rarely occur in practice, may be specified via
  2246 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2247 
  2248   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2249 
  2250 The result contains an implicit sort hypotheses as before --
  2251 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2252 normalization.
  2253 
  2254 * Generalized Isar history, with support for linear undo, direct state
  2255 addressing etc.
  2256 
  2257 * Changed defaults for unify configuration options:
  2258 
  2259   unify_trace_bound = 50 (formerly 25)
  2260   unify_search_bound = 60 (formerly 30)
  2261 
  2262 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2263 
  2264   a) On theory merge, the last set of code equations for a particular
  2265      constant is taken (in accordance with the policy applied by other
  2266      parts of the code generator framework).
  2267 
  2268   b) Code equations stemming from explicit declarations (e.g. code
  2269      attribute) gain priority over default code equations stemming
  2270      from definition, primrec, fun etc.
  2271 
  2272 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2273 
  2274 * Unified theorem tables for both code generators.  Thus [code
  2275 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2276 
  2277 * Command 'find_consts' searches for constants based on type and name
  2278 patterns, e.g.
  2279 
  2280     find_consts "_ => bool"
  2281 
  2282 By default, matching is against subtypes, but it may be restricted to
  2283 the whole type.  Searching by name is possible.  Multiple queries are
  2284 conjunctive and queries may be negated by prefixing them with a
  2285 hyphen:
  2286 
  2287     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2288 
  2289 * New 'find_theorems' criterion "solves" matches theorems that
  2290 directly solve the current goal (modulo higher-order unification).
  2291 
  2292 * Auto solve feature for main theorem statements: whenever a new goal
  2293 is stated, "find_theorems solves" is called; any theorems that could
  2294 solve the lemma directly are listed as part of the goal state.
  2295 Cf. associated options in Proof General Isabelle settings menu,
  2296 enabled by default, with reasonable timeout for pathological cases of
  2297 higher-order unification.
  2298 
  2299 
  2300 *** Document preparation ***
  2301 
  2302 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2303 demanding keyword 'by' and supporting the full method expression
  2304 syntax just like the Isar command 'by'.
  2305 
  2306 
  2307 *** HOL ***
  2308 
  2309 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2310 points Main and Complex_Main remain as before.
  2311 
  2312 * Logic image HOL-Plain provides a minimal HOL with the most important
  2313 tools available (inductive, datatype, primrec, ...).  This facilitates
  2314 experimentation and tool development.  Note that user applications
  2315 (and library theories) should never refer to anything below theory
  2316 Main, as before.
  2317 
  2318 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2319 experimentation due to shorter build times.
  2320 
  2321 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2322 were previously part of former HOL-Complex.  Entry point Hyperreal
  2323 remains valid, but theories formerly using Complex_Main should now use
  2324 new entry point Hypercomplex.
  2325 
  2326 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2327 Posix processes.  Avoids potentially expensive forking of the ML
  2328 process.  New thread-based implementation also works on non-Unix
  2329 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2330 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2331 commands are covered in the isar-ref manual.
  2332 
  2333 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2334 sledgehammer without local ATP installation (Vampire etc.). Other
  2335 provers may be included via suitable ML wrappers, see also
  2336 src/HOL/ATP_Linkup.thy.
  2337 
  2338 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2339 menu.
  2340 
  2341 * The metis method no longer fails because the theorem is too trivial
  2342 (contains the empty clause).
  2343 
  2344 * The metis method now fails in the usual manner, rather than raising
  2345 an exception, if it determines that it cannot prove the theorem.
  2346 
  2347 * Method "coherent" implements a prover for coherent logic (see also
  2348 src/Tools/coherent.ML).
  2349 
  2350 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2351 "undefined" is the right choice to replace "arbitrary", though
  2352 logically there is no difference.  INCOMPATIBILITY.
  2353 
  2354 * Command "value" now integrates different evaluation mechanisms.  The
  2355 result of the first successful evaluation mechanism is printed.  In
  2356 square brackets a particular named evaluation mechanisms may be
  2357 specified (currently, [SML], [code] or [nbe]).  See further
  2358 src/HOL/ex/Eval_Examples.thy.
  2359 
  2360 * Normalization by evaluation now allows non-leftlinear equations.
  2361 Declare with attribute [code nbe].
  2362 
  2363 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2364 as the structured Isar versions "cases" and "induct", cf. the
  2365 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2366 are now presented as a list of individual projections
  2367 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2368 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2369 rare situations a different rule is selected --- notably nested tuple
  2370 elimination instead of former prod.exhaust: use explicit (case_tac t
  2371 rule: prod.exhaust) here.
  2372 
  2373 * Attributes "cases", "induct", "coinduct" support "del" option.
  2374 
  2375 * Removed fact "case_split_thm", which duplicates "case_split".
  2376 
  2377 * The option datatype has been moved to a new theory Option.  Renamed
  2378 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2379 
  2380 * New predicate "strict_mono" classifies strict functions on partial
  2381 orders.  With strict functions on linear orders, reasoning about
  2382 (in)equalities is facilitated by theorems "strict_mono_eq",
  2383 "strict_mono_less_eq" and "strict_mono_less".
  2384 
  2385 * Some set operations are now proper qualified constants with
  2386 authentic syntax.  INCOMPATIBILITY:
  2387 
  2388     op Int ~>   Set.Int
  2389     op Un ~>    Set.Un
  2390     INTER ~>    Set.INTER
  2391     UNION ~>    Set.UNION
  2392     Inter ~>    Set.Inter
  2393     Union ~>    Set.Union
  2394     {} ~>       Set.empty
  2395     UNIV ~>     Set.UNIV
  2396 
  2397 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2398 theory Set.
  2399 
  2400 * Auxiliary class "itself" has disappeared -- classes without any
  2401 parameter are treated as expected by the 'class' command.
  2402 
  2403 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2404 
  2405 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2406 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2407 
  2408 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2409 method "approximation".  It proves formulas on real values by using
  2410 interval arithmetic.  In the formulas are also the transcendental
  2411 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2412 allowed. For examples see
  2413 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2414 
  2415 * Theory "Reflection" now resides in HOL/Library.
  2416 
  2417 * Entry point to Word library now simply named "Word".
  2418 INCOMPATIBILITY.
  2419 
  2420 * Made source layout more coherent with logical distribution
  2421 structure:
  2422 
  2423     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2424     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2425     src/HOL/Library/GCD.thy ~> src/HOL/
  2426     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2427     src/HOL/Library/Parity.thy ~> src/HOL/
  2428     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2429     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2430     src/HOL/Real/Lubs.thy ~> src/HOL/
  2431     src/HOL/Real/PReal.thy ~> src/HOL/
  2432     src/HOL/Real/Rational.thy ~> src/HOL/
  2433     src/HOL/Real/RComplete.thy ~> src/HOL/
  2434     src/HOL/Real/RealDef.thy ~> src/HOL/
  2435     src/HOL/Real/RealPow.thy ~> src/HOL/
  2436     src/HOL/Real/Real.thy ~> src/HOL/
  2437     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2438     src/HOL/Complex/Complex.thy ~> src/HOL/
  2439     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2440     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2441     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2442     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2443     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2444     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2445     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2446     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2447     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2448     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2449     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2450     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2451     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2452     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2453     src/HOL/Real/Float ~> src/HOL/Library/
  2454     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2455     src/HOL/Real/RealVector.thy ~> src/HOL/
  2456 
  2457     src/HOL/arith_data.ML ~> src/HOL/Tools
  2458     src/HOL/hologic.ML ~> src/HOL/Tools
  2459     src/HOL/simpdata.ML ~> src/HOL/Tools
  2460     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2461     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2462     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2463     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2464     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2465     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2466     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2467 
  2468     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2469     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2470     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2471     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2472     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2473     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2474 
  2475 * If methods "eval" and "evaluation" encounter a structured proof
  2476 state with !!/==>, only the conclusion is evaluated to True (if
  2477 possible), avoiding strange error messages.
  2478 
  2479 * Method "sizechange" automates termination proofs using (a
  2480 modification of) the size-change principle.  Requires SAT solver.  See
  2481 src/HOL/ex/Termination.thy for examples.
  2482 
  2483 * Simplifier: simproc for let expressions now unfolds if bound
  2484 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2485 
  2486 * Method "arith": Linear arithmetic now ignores all inequalities when
  2487 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2488 
  2489 * New attribute "arith" for facts that should always be used
  2490 automatically by arithmetic. It is intended to be used locally in
  2491 proofs, e.g.
  2492 
  2493   assumes [arith]: "x > 0"
  2494 
  2495 Global usage is discouraged because of possible performance impact.
  2496 
  2497 * New classes "top" and "bot" with corresponding operations "top" and
  2498 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2499 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2500 
  2501 * Changed definition lemma "less_fun_def" in order to provide an
  2502 instance for preorders on functions; use lemma "less_le" instead.
  2503 INCOMPATIBILITY.
  2504 
  2505 * Theory Orderings: class "wellorder" moved here, with explicit
  2506 induction rule "less_induct" as assumption.  For instantiation of
  2507 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2508 INCOMPATIBILITY.
  2509 
  2510 * Theory Orderings: added class "preorder" as superclass of "order".
  2511 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2512 etc. slightly changed.  Some theorems named order_class.* now named
  2513 preorder_class.*.
  2514 
  2515 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2516 "diag" to "Id_on".
  2517 
  2518 * Theory Finite_Set: added a new fold combinator of type
  2519 
  2520   ('a => 'b => 'b) => 'b => 'a set => 'b
  2521 
  2522 Occasionally this is more convenient than the old fold combinator
  2523 which is now defined in terms of the new one and renamed to
  2524 fold_image.
  2525 
  2526 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2527 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2528 extended with further lemmas!).  At the moment both still exist but
  2529 the former will disappear at some point.
  2530 
  2531 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2532 class recpower.  Type-specific simp rules for various recpower types
  2533 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2534 
  2535 rat_power_0    -> power_0
  2536 rat_power_Suc  -> power_Suc
  2537 realpow_0      -> power_0
  2538 realpow_Suc    -> power_Suc
  2539 complexpow_0   -> power_0
  2540 complexpow_Suc -> power_Suc
  2541 power_poly_0   -> power_0
  2542 power_poly_Suc -> power_Suc
  2543 
  2544 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2545 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2546 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2547 of lemmas from Divides has been generalized from nat to class
  2548 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2549 renames resulting from duplicate elimination:
  2550 
  2551     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2552     zero_dvd_iff ~>         dvd_0_left_iff
  2553     dvd_0 ~>                dvd_0_right
  2554     DIVISION_BY_ZERO_DIV ~> div_by_0
  2555     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2556     mult_div ~>             div_mult_self2_is_id
  2557     mult_mod ~>             mod_mult_self2_is_0
  2558 
  2559 * Theory IntDiv: removed many lemmas that are instances of class-based
  2560 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2561 rename old lemmas as follows:
  2562 
  2563 dvd_diff               -> nat_dvd_diff
  2564 dvd_zminus_iff         -> dvd_minus_iff
  2565 mod_add1_eq            -> mod_add_eq
  2566 mod_mult1_eq           -> mod_mult_right_eq
  2567 mod_mult1_eq'          -> mod_mult_left_eq
  2568 mod_mult_distrib_mod   -> mod_mult_eq
  2569 nat_mod_add_left_eq    -> mod_add_left_eq
  2570 nat_mod_add_right_eq   -> mod_add_right_eq
  2571 nat_mod_div_trivial    -> mod_div_trivial
  2572 nat_mod_mod_trivial    -> mod_mod_trivial
  2573 zdiv_zadd_self1        -> div_add_self1
  2574 zdiv_zadd_self2        -> div_add_self2
  2575 zdiv_zmult_self1       -> div_mult_self2_is_id
  2576 zdiv_zmult_self2       -> div_mult_self1_is_id
  2577 zdvd_triv_left         -> dvd_triv_left
  2578 zdvd_triv_right        -> dvd_triv_right
  2579 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2580 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2581 zmod_zadd_left_eq      -> mod_add_left_eq
  2582 zmod_zadd_right_eq     -> mod_add_right_eq
  2583 zmod_zadd_self1        -> mod_add_self1
  2584 zmod_zadd_self2        -> mod_add_self2
  2585 zmod_zadd1_eq          -> mod_add_eq
  2586 zmod_zdiff1_eq         -> mod_diff_eq
  2587 zmod_zdvd_zmod         -> mod_mod_cancel
  2588 zmod_zmod_cancel       -> mod_mod_cancel
  2589 zmod_zmult_self1       -> mod_mult_self2_is_0
  2590 zmod_zmult_self2       -> mod_mult_self1_is_0
  2591 zmod_1                 -> mod_by_1
  2592 zdiv_1                 -> div_by_1
  2593 zdvd_abs1              -> abs_dvd_iff
  2594 zdvd_abs2              -> dvd_abs_iff
  2595 zdvd_refl              -> dvd_refl
  2596 zdvd_trans             -> dvd_trans
  2597 zdvd_zadd              -> dvd_add
  2598 zdvd_zdiff             -> dvd_diff
  2599 zdvd_zminus_iff        -> dvd_minus_iff
  2600 zdvd_zminus2_iff       -> minus_dvd_iff
  2601 zdvd_zmultD            -> dvd_mult_right
  2602 zdvd_zmultD2           -> dvd_mult_left
  2603 zdvd_zmult_mono        -> mult_dvd_mono
  2604 zdvd_0_right           -> dvd_0_right
  2605 zdvd_0_left            -> dvd_0_left_iff
  2606 zdvd_1_left            -> one_dvd
  2607 zminus_dvd_iff         -> minus_dvd_iff
  2608 
  2609 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2610 
  2611 * The real numbers offer decimal input syntax: 12.34 is translated
  2612 into 1234/10^2. This translation is not reversed upon output.
  2613 
  2614 * Theory Library/Polynomial defines an abstract type 'a poly of
  2615 univariate polynomials with coefficients of type 'a.  In addition to
  2616 the standard ring operations, it also supports div and mod.  Code
  2617 generation is also supported, using list-style constructors.
  2618 
  2619 * Theory Library/Inner_Product defines a class of real_inner for real
  2620 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2621 => real.  Class real_inner is a subclass of real_normed_vector from
  2622 theory RealVector.
  2623 
  2624 * Theory Library/Product_Vector provides instances for the product
  2625 type 'a * 'b of several classes from RealVector and Inner_Product.
  2626 Definitions of addition, subtraction, scalar multiplication, norms,
  2627 and inner products are included.
  2628 
  2629 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2630 addition to the field operations, numerals and case syntax are also
  2631 supported.
  2632 
  2633 * Theory Library/Diagonalize provides constructive version of Cantor's
  2634 first diagonalization argument.
  2635 
  2636 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2637 zlcm (for int); carried together from various gcd/lcm developements in
  2638 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2639 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2640 may recover tupled syntax as follows:
  2641 
  2642     hide (open) const gcd
  2643     abbreviation gcd where
  2644       "gcd == (%(a, b). GCD.gcd a b)"
  2645     notation (output)
  2646       GCD.gcd ("gcd '(_, _')")
  2647 
  2648 The same works for lcm, zgcd, zlcm.
  2649 
  2650 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2651 instantiations for algebraic structures.  Removed some duplicate
  2652 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2653 
  2654 * ML antiquotation @{code} takes a constant as argument and generates
  2655 corresponding code in background and inserts name of the corresponding
  2656 resulting ML value/function/datatype constructor binding in place.
  2657 All occurrences of @{code} with a single ML block are generated
  2658 simultaneously.  Provides a generic and safe interface for
  2659 instrumentalizing code generation.  See
  2660 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2661 In future you ought to refrain from ad-hoc compiling generated SML
  2662 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2663 cannot refer to constants for which user-defined serializations are
  2664 set.  Refer to the corresponding ML counterpart directly in that
  2665 cases.
  2666 
  2667 * Command 'rep_datatype': instead of theorem names the command now
  2668 takes a list of terms denoting the constructors of the type to be
  2669 represented as datatype.  The characteristic theorems have to be
  2670 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2671 have disappeared in favour of existing ones:
  2672 
  2673     unit_induct                 ~> unit.induct
  2674     prod_induct                 ~> prod.induct
  2675     sum_induct                  ~> sum.induct
  2676     Suc_Suc_eq                  ~> nat.inject
  2677     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2678 
  2679 
  2680 *** HOL-Algebra ***
  2681 
  2682 * New locales for orders and lattices where the equivalence relation
  2683 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2684 locales use a record structure with field eq for the equivalence.
  2685 
  2686 * New theory of factorial domains.
  2687 
  2688 * Units_l_inv and Units_r_inv are now simp rules by default.
  2689 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2690 and/or r_inv will now also require deletion of these lemmas.
  2691 
  2692 * Renamed the following theorems, INCOMPATIBILITY:
  2693 
  2694 UpperD ~> Upper_memD
  2695 LowerD ~> Lower_memD
  2696 least_carrier ~> least_closed
  2697 greatest_carrier ~> greatest_closed
  2698 greatest_Lower_above ~> greatest_Lower_below
  2699 one_zero ~> carrier_one_zero
  2700 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2701 
  2702 
  2703 *** HOL-Nominal ***
  2704 
  2705 * Nominal datatypes can now contain type-variables.
  2706 
  2707 * Commands 'nominal_inductive' and 'equivariance' work with local
  2708 theory targets.
  2709 
  2710 * Nominal primrec can now works with local theory targets and its
  2711 specification syntax now conforms to the general format as seen in
  2712 'inductive' etc.
  2713 
  2714 * Method "perm_simp" honours the standard simplifier attributes
  2715 (no_asm), (no_asm_use) etc.
  2716 
  2717 * The new predicate #* is defined like freshness, except that on the
  2718 left hand side can be a set or list of atoms.
  2719 
  2720 * Experimental command 'nominal_inductive2' derives strong induction
  2721 principles for inductive definitions.  In contrast to
  2722 'nominal_inductive', which can only deal with a fixed number of
  2723 binders, it can deal with arbitrary expressions standing for sets of
  2724 atoms to be avoided.  The only inductive definition we have at the
  2725 moment that needs this generalisation is the typing rule for Lets in
  2726 the algorithm W:
  2727 
  2728  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2729  -----------------------------------------------------------------
  2730          Gamma |- Let x be t1 in t2 : T2
  2731 
  2732 In this rule one wants to avoid all the binders that are introduced by
  2733 "close Gamma T1".  We are looking for other examples where this
  2734 feature might be useful.  Please let us know.
  2735 
  2736 
  2737 *** HOLCF ***
  2738 
  2739 * Reimplemented the simplification procedure for proving continuity
  2740 subgoals.  The new simproc is extensible; users can declare additional
  2741 continuity introduction rules with the attribute [cont2cont].
  2742 
  2743 * The continuity simproc now uses a different introduction rule for
  2744 solving continuity subgoals on terms with lambda abstractions.  In
  2745 some rare cases the new simproc may fail to solve subgoals that the
  2746 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2747 Potential INCOMPATIBILITY.
  2748 
  2749 * Command 'fixrec': specification syntax now conforms to the general
  2750 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2751 examples.  INCOMPATIBILITY.
  2752 
  2753 
  2754 *** ZF ***
  2755 
  2756 * Proof of Zorn's Lemma for partial orders.
  2757 
  2758 
  2759 *** ML ***
  2760 
  2761 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2762 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2763 depends on multithreading, so timouts will not work before Poly/ML
  2764 5.2.1!
  2765 
  2766 * High-level support for concurrent ML programming, see
  2767 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2768 particularly convenient to organize independent functional
  2769 computations.  The concept of "synchronized variables" provides a
  2770 higher-order interface for components with shared state, avoiding the
  2771 delicate details of mutexes and condition variables.  (Requires
  2772 Poly/ML 5.2.1 or later.)
  2773 
  2774 * ML bindings produced via Isar commands are stored within the Isar
  2775 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2776 become thread-safe and work with undo as expected (concerning
  2777 top-level bindings, not side-effects on global references).
  2778 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2779 compiler at runtime; really global bindings need to be given outside a
  2780 theory.  (Requires Poly/ML 5.2 or later.)
  2781 
  2782 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2783 context.  Top-level ML bindings are stored within the proof context in
  2784 a purely sequential fashion, disregarding the nested proof structure.
  2785 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2786 proof.  (Requires Poly/ML 5.2 or later.)
  2787 
  2788 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2789 and Method.setup, as well as Isar commands 'attribute_setup' and
  2790 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2791 existing code accordingly, or use plain 'setup' together with old
  2792 Method.add_method.
  2793 
  2794 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2795 to 'a -> thm, while results are always tagged with an authentic oracle
  2796 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2797 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2798 accordingly.  Note that extra performance may be gained by producing
  2799 the cterm carefully, avoiding slow Thm.cterm_of.
  2800 
  2801 * Simplified interface for defining document antiquotations via
  2802 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2803 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2804 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2805 examples.
  2806 
  2807 * More systematic treatment of long names, abstract name bindings, and
  2808 name space operations.  Basic operations on qualified names have been
  2809 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2810 Long_Name.append.  Old type bstring has been mostly replaced by
  2811 abstract type binding (see structure Binding), which supports precise
  2812 qualification by packages and local theory targets, as well as proper
  2813 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2814 bstring values into Binding.name, or better pass through abstract
  2815 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2816 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2817 
  2818 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2819 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2820 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2821 
  2822 * Disposed old type and term read functions (Sign.read_def_typ,
  2823 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2824 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2825 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2826 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2827 resort for legacy applications.
  2828 
  2829 * Disposed old declarations, tactics, tactic combinators that refer to
  2830 the simpset or claset of an implicit theory (such as Addsimps,
  2831 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2832 embedded ML text, or local_simpset_of with a proper context passed as
  2833 explicit runtime argument.
  2834 
  2835 * Rules and tactics that read instantiations (read_instantiate,
  2836 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2837 context, which is required for parsing and type-checking.  Moreover,
  2838 the variables are specified as plain indexnames, not string encodings
  2839 thereof.  INCOMPATIBILITY.
  2840 
  2841 * Generic Toplevel.add_hook interface allows to analyze the result of
  2842 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2843 for theorem dependency output of transactions resulting in a new
  2844 theory state.
  2845 
  2846 * ML antiquotations: block-structured compilation context indicated by
  2847 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2848 
  2849   @{binding name}                         - basic name binding
  2850   @{let ?pat = term}                      - term abbreviation (HO matching)
  2851   @{note name = fact}                     - fact abbreviation
  2852   @{thm fact}                             - singleton fact (with attributes)
  2853   @{thms fact}                            - general fact (with attributes)
  2854   @{lemma prop by method}                 - singleton goal
  2855   @{lemma prop by meth1 meth2}            - singleton goal
  2856   @{lemma prop1 ... propN by method}      - general goal
  2857   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2858   @{lemma (open) ...}                     - open derivation
  2859 
  2860 
  2861 *** System ***
  2862 
  2863 * The Isabelle "emacs" tool provides a specific interface to invoke
  2864 Proof General / Emacs, with more explicit failure if that is not
  2865 installed (the old isabelle-interface script silently falls back on
  2866 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2867 installation location of the Proof General distribution.
  2868 
  2869 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2870 the Isabelle process into a JVM/Scala application.  See
  2871 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2872 process wrapper has been discontinued.)
  2873 
  2874 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2875 
  2876 * Various status messages (with exact source position information) are
  2877 emitted, if proper markup print mode is enabled.  This allows
  2878 user-interface components to provide detailed feedback on internal
  2879 prover operations.
  2880 
  2881 
  2882 
  2883 New in Isabelle2008 (June 2008)
  2884 -------------------------------
  2885 
  2886 *** General ***
  2887 
  2888 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2889 and updated, with formally checked references as hyperlinks.
  2890 
  2891 * Theory loader: use_thy (and similar operations) no longer set the
  2892 implicit ML context, which was occasionally hard to predict and in
  2893 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2894 provides a proper context already.
  2895 
  2896 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2897 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2898 'use' within a theory file will do the job.
  2899 
  2900 * Name space merge now observes canonical order, i.e. the second space
  2901 is inserted into the first one, while existing entries in the first
  2902 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2903 swap theory imports.
  2904 
  2905 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2906 INCOMPATIBILITY in identifier syntax etc.
  2907 
  2908 * Outer syntax: string tokens no longer admit escaped white space,
  2909 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2910 white space without escapes.
  2911 
  2912 * Outer syntax: string tokens may contain arbitrary character codes
  2913 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2914 "foo_bar".
  2915 
  2916 
  2917 *** Pure ***
  2918 
  2919 * Context-dependent token translations.  Default setup reverts locally
  2920 fixed variables, and adds hilite markup for undeclared frees.
  2921 
  2922 * Unused theorems can be found using the new command 'unused_thms'.
  2923 There are three ways of invoking it:
  2924 
  2925 (1) unused_thms
  2926      Only finds unused theorems in the current theory.
  2927 
  2928 (2) unused_thms thy_1 ... thy_n -
  2929      Finds unused theorems in the current theory and all of its ancestors,
  2930      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2931 
  2932 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2933      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2934      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2935      their ancestors.
  2936 
  2937 In order to increase the readability of the list produced by
  2938 unused_thms, theorems that have been created by a particular instance
  2939 of a theory command such as 'inductive' or 'function' are considered
  2940 to belong to the same "group", meaning that if at least one theorem in
  2941 this group is used, the other theorems in the same group are no longer
  2942 reported as unused.  Moreover, if all theorems in the group are
  2943 unused, only one theorem in the group is displayed.
  2944 
  2945 Note that proof objects have to be switched on in order for
  2946 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2947 usually the case when using Proof General with the default settings).
  2948 
  2949 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2950 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2951 duplicate fact bindings, or even accidental fact duplications.  Note
  2952 that tools may maintain dynamically scoped facts systematically, using
  2953 PureThy.add_thms_dynamic.
  2954 
  2955 * Command 'hide' now allows to hide from "fact" name space as well.
  2956 
  2957 * Eliminated destructive theorem database, simpset, claset, and
  2958 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2959 update of theories within ML code.
  2960 
  2961 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2962 INCOMPATIBILITY, object-logics depending on former Pure require
  2963 additional setup PureThy.old_appl_syntax_setup; object-logics
  2964 depending on former CPure need to refer to Pure.
  2965 
  2966 * Commands 'use' and 'ML' are now purely functional, operating on
  2967 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2968 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2969 INCOMPATIBILITY.
  2970 
  2971 * Command 'setup': discontinued implicit version with ML reference.
  2972 
  2973 * Instantiation target allows for simultaneous specification of class
  2974 instance operations together with an instantiation proof.
  2975 Type-checking phase allows to refer to class operations uniformly.
  2976 See src/HOL/Complex/Complex.thy for an Isar example and
  2977 src/HOL/Library/Eval.thy for an ML example.
  2978 
  2979 * Indexing of literal facts: be more serious about including only
  2980 facts from the visible specification/proof context, but not the
  2981 background context (locale etc.).  Affects `prop` notation and method
  2982 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2983 situations.
  2984 
  2985 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2986 "(open)" option, which used to expose internal bound variables to the
  2987 proof text.
  2988 
  2989 * Isar statements: removed obsolete case "rule_context".
  2990 INCOMPATIBILITY, better use explicit fixes/assumes.
  2991 
  2992 * Locale proofs: default proof step now includes 'unfold_locales';
  2993 hence 'proof' without argument may be used to unfold locale
  2994 predicates.
  2995 
  2996 
  2997 *** Document preparation ***
  2998 
  2999 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  3000 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  3001 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  3002 spot); renamed link color from "darkblue" to "linkcolor" (default
  3003 value unchanged, can be redefined via \definecolor); no longer sets
  3004 "a4paper" option (unnecessary or even intrusive).
  3005 
  3006 * Antiquotation @{lemma A method} proves proposition A by the given
  3007 method (either a method name or a method name plus (optional) method
  3008 arguments in parentheses) and prints A just like @{prop A}.
  3009 
  3010 
  3011 *** HOL ***
  3012 
  3013 * New primrec package.  Specification syntax conforms in style to
  3014 definition/function/....  No separate induction rule is provided.  The
  3015 "primrec" command distinguishes old-style and new-style specifications
  3016 by syntax.  The former primrec package is now named OldPrimrecPackage.
  3017 When adjusting theories, beware: constants stemming from new-style
  3018 primrec specifications have authentic syntax.
  3019 
  3020 * Metis prover is now an order of magnitude faster, and also works
  3021 with multithreading.
  3022 
  3023 * Metis: the maximum number of clauses that can be produced from a
  3024 theorem is now given by the attribute max_clauses.  Theorems that
  3025 exceed this number are ignored, with a warning printed.
  3026 
  3027 * Sledgehammer no longer produces structured proofs by default. To
  3028 enable, declare [[sledgehammer_full = true]].  Attributes
  3029 reconstruction_modulus, reconstruction_sorts renamed
  3030 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  3031 
  3032 * Method "induct_scheme" derives user-specified induction rules
  3033 from well-founded induction and completeness of patterns. This factors
  3034 out some operations that are done internally by the function package
  3035 and makes them available separately.  See
  3036 src/HOL/ex/Induction_Scheme.thy for examples.
  3037 
  3038 * More flexible generation of measure functions for termination
  3039 proofs: Measure functions can be declared by proving a rule of the
  3040 form "is_measure f" and giving it the [measure_function] attribute.
  3041 The "is_measure" predicate is logically meaningless (always true), and
  3042 just guides the heuristic.  To find suitable measure functions, the
  3043 termination prover sets up the goal "is_measure ?f" of the appropriate
  3044 type and generates all solutions by prolog-style backwards proof using
  3045 the declared rules.
  3046 
  3047 This setup also deals with rules like 
  3048 
  3049   "is_measure f ==> is_measure (list_size f)"
  3050 
  3051 which accommodates nested datatypes that recurse through lists.
  3052 Similar rules are predeclared for products and option types.
  3053 
  3054 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  3055 
  3056   INCOMPATIBILITIES:
  3057 
  3058   - Definitions of overloaded constants on sets have to be replaced by
  3059     definitions on => and bool.
  3060 
  3061   - Some definitions of overloaded operators on sets can now be proved
  3062     using the definitions of the operators on => and bool.  Therefore,
  3063     the following theorems have been renamed:
  3064 
  3065       subset_def   -> subset_eq
  3066       psubset_def  -> psubset_eq
  3067       set_diff_def -> set_diff_eq
  3068       Compl_def    -> Compl_eq
  3069       Sup_set_def  -> Sup_set_eq
  3070       Inf_set_def  -> Inf_set_eq
  3071       sup_set_def  -> sup_set_eq
  3072       inf_set_def  -> inf_set_eq
  3073 
  3074   - Due to the incompleteness of the HO unification algorithm, some
  3075     rules such as subst may require manual instantiation, if some of
  3076     the unknowns in the rule is a set.
  3077 
  3078   - Higher order unification and forward proofs:
  3079     The proof pattern
  3080 
  3081       have "P (S::'a set)" <...>
  3082       then have "EX S. P S" ..
  3083 
  3084     no longer works (due to the incompleteness of the HO unification
  3085     algorithm) and must be replaced by the pattern
  3086 
  3087       have "EX S. P S"
  3088       proof
  3089         show "P S" <...>
  3090       qed
  3091 
  3092   - Calculational reasoning with subst (or similar rules):
  3093     The proof pattern
  3094 
  3095       have "P (S::'a set)" <...>
  3096       also have "S = T" <...>
  3097       finally have "P T" .
  3098 
  3099     no longer works (for similar reasons as the previous example) and
  3100     must be replaced by something like
  3101 
  3102       have "P (S::'a set)" <...>
  3103       moreover have "S = T" <...>
  3104       ultimately have "P T" by simp
  3105 
  3106   - Tactics or packages written in ML code:
  3107     Code performing pattern matching on types via
  3108 
  3109       Type ("set", [T]) => ...
  3110 
  3111     must be rewritten. Moreover, functions like strip_type or
  3112     binder_types no longer return the right value when applied to a
  3113     type of the form
  3114 
  3115       T1 => ... => Tn => U => bool
  3116 
  3117     rather than
  3118 
  3119       T1 => ... => Tn => U set
  3120 
  3121 * Merged theories Wellfounded_Recursion, Accessible_Part and
  3122 Wellfounded_Relations to theory Wellfounded.
  3123 
  3124 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  3125 
  3126 * Class finite no longer treats UNIV as class parameter.  Use class
  3127 enum from theory Library/Enum instead to achieve a similar effect.
  3128 INCOMPATIBILITY.
  3129 
  3130 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  3131 and "Cons".  INCOMPATIBILITY.
  3132 
  3133 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  3134 Potential INCOMPATIBILITY.
  3135 
  3136 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  3137 injective_fst_snd removed, use split_eta and prod_eqI instead.
  3138 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  3139 
  3140 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  3141 the same name in theory Orderings:
  3142 
  3143   less_trans
  3144   less_linear
  3145   le_imp_less_or_eq
  3146   le_less_trans
  3147   less_le_trans
  3148   less_not_sym
  3149   less_asym
  3150 
  3151 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  3152 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  3153 and different variable names.
  3154 
  3155 * Library/Option_ord.thy: Canonical order on option type.
  3156 
  3157 * Library/RBT.thy: Red-black trees, an efficient implementation of
  3158 finite maps.
  3159 
  3160 * Library/Countable.thy: Type class for countable types.
  3161 
  3162 * Theory Int: The representation of numerals has changed.  The infix
  3163 operator BIT and the bit datatype with constructors B0 and B1 have
  3164 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  3165 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  3166 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  3167 accordingly.
  3168 
  3169 * Theory Nat: definition of <= and < on natural numbers no longer
  3170 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  3171 le_def and less_def have disappeared.  Consider lemmas not_less
  3172 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  3173 
  3174 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  3175 (whose purpose mainly is for various fold_set functionals) have been
  3176 abandoned in favor of the existing algebraic classes
  3177 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  3178 lower_semilattice (resp. upper_semilattice) and linorder.
  3179 INCOMPATIBILITY.
  3180 
  3181 * Theory Transitive_Closure: induct and cases rules now declare proper
  3182 case_names ("base" and "step").  INCOMPATIBILITY.
  3183 
  3184 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  3185 lattices.  The form set-specific version is available as
  3186 Inductive.lfp_ordinal_induct_set.
  3187 
  3188 * Renamed theorems "power.simps" to "power_int.simps".
  3189 INCOMPATIBILITY.
  3190 
  3191 * Class semiring_div provides basic abstract properties of semirings
  3192 with division and modulo operations.  Subsumes former class dvd_mod.
  3193 
  3194 * Merged theories IntDef, Numeral and IntArith into unified theory
  3195 Int.  INCOMPATIBILITY.
  3196 
  3197 * Theory Library/Code_Index: type "index" now represents natural
  3198 numbers rather than integers.  INCOMPATIBILITY.
  3199 
  3200 * New class "uminus" with operation "uminus" (split of from class
  3201 "minus" which now only has operation "minus", binary).
  3202 INCOMPATIBILITY.
  3203 
  3204 * Constants "card", "internal_split", "option_map" now with authentic
  3205 syntax.  INCOMPATIBILITY.
  3206 
  3207 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3208 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3209 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3210 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3211 Sup_set_def, le_def, less_def, option_map_def now with object
  3212 equality.  INCOMPATIBILITY.
  3213 
  3214 * Records. Removed K_record, and replaced it by pure lambda term
  3215 %x. c. The simplifier setup is now more robust against eta expansion.
  3216 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3217 
  3218 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3219 
  3220 * Library/ListVector: new theory of arithmetic vector operations.
  3221 
  3222 * Library/Order_Relation: new theory of various orderings as sets of
  3223 pairs.  Defines preorders, partial orders, linear orders and
  3224 well-orders on sets and on types.
  3225 
  3226 
  3227 *** ZF ***
  3228 
  3229 * Renamed some theories to allow to loading both ZF and HOL in the
  3230 same session:
  3231 
  3232   Datatype  -> Datatype_ZF
  3233   Inductive -> Inductive_ZF
  3234   Int       -> Int_ZF
  3235   IntDiv    -> IntDiv_ZF
  3236   Nat       -> Nat_ZF
  3237   List      -> List_ZF
  3238   Main      -> Main_ZF
  3239 
  3240 INCOMPATIBILITY: ZF theories that import individual theories below
  3241 Main might need to be adapted.  Regular theory Main is still
  3242 available, as trivial extension of Main_ZF.
  3243 
  3244 
  3245 *** ML ***
  3246 
  3247 * ML within Isar: antiquotation @{const name} or @{const
  3248 name(typargs)} produces statically-checked Const term.
  3249 
  3250 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3251 (of the same name).  Removed obsolete print command.
  3252 
  3253 * Removed obsolete "use_legacy_bindings" function.
  3254 
  3255 * The ``print mode'' is now a thread-local value derived from a global
  3256 template (the former print_mode reference), thus access becomes
  3257 non-critical.  The global print_mode reference is for session
  3258 management only; user-code should use print_mode_value,
  3259 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3260 
  3261 * Functions system/system_out provide a robust way to invoke external
  3262 shell commands, with propagation of interrupts (requires Poly/ML
  3263 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3264 
  3265 
  3266 *** System ***
  3267 
  3268 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3269 in accordance with Proof General 3.7, which prefers GNU emacs.
  3270 
  3271 * isatool tty runs Isabelle process with plain tty interaction;
  3272 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3273 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3274 
  3275 * isatool browser now works with Cygwin as well, using general
  3276 "javapath" function defined in Isabelle process environment.
  3277 
  3278 * YXML notation provides a simple and efficient alternative to
  3279 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3280 isatool yxml as described in the Isabelle system manual.
  3281 
  3282 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3283 provides general wrapper for managing an Isabelle process in a robust
  3284 fashion, with ``cooked'' output from stdin/stderr.
  3285 
  3286 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3287 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3288 
  3289 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3290 way of changing the user's settings is via
  3291 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3292 script.
  3293 
  3294 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3295 cores of the underlying machine, which is a good starting point for
  3296 optimal performance tuning.  The corresponding usedir option -M allows
  3297 "max" as an alias for "0".  WARNING: does not work on certain versions
  3298 of Mac OS (with Poly/ML 5.1).
  3299 
  3300 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3301 adverse effect of Isabelle flooding interactive front-ends (notably
  3302 ProofGeneral / XEmacs).
  3303 
  3304 
  3305 
  3306 New in Isabelle2007 (November 2007)
  3307 -----------------------------------
  3308 
  3309 *** General ***
  3310 
  3311 * More uniform information about legacy features, notably a
  3312 warning/error of "Legacy feature: ...", depending on the state of the
  3313 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3314 legacy features will disappear eventually.
  3315 
  3316 * Theory syntax: the header format ``theory A = B + C:'' has been
  3317 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3318 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3319 
  3320 * Theory syntax: the old non-Isar theory file format has been
  3321 discontinued altogether.  Note that ML proof scripts may still be used
  3322 with Isar theories; migration is usually quite simple with the ML
  3323 function use_legacy_bindings.  INCOMPATIBILITY.
  3324 
  3325 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3326 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3327 quotes.
  3328 
  3329 * Theory loader: be more serious about observing the static theory
  3330 header specifications (including optional directories), but not the
  3331 accidental file locations of previously successful loads.  The strict
  3332 update policy of former update_thy is now already performed by
  3333 use_thy, so the former has been removed; use_thys updates several
  3334 theories simultaneously, just as 'imports' within a theory header
  3335 specification, but without merging the results.  Potential
  3336 INCOMPATIBILITY: may need to refine theory headers and commands
  3337 ROOT.ML which depend on load order.
  3338 
  3339 * Theory loader: optional support for content-based file
  3340 identification, instead of the traditional scheme of full physical
  3341 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3342 (cf. the system manual).  The new scheme allows to work with
  3343 non-finished theories in persistent session images, such that source
  3344 files may be moved later on without requiring reloads.
  3345 
  3346 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3347 file (with the same base name as the theory) are considered a legacy
  3348 feature, which will disappear eventually. Even now, the theory loader
  3349 no longer maintains dependencies on such files.
  3350 
  3351 * Syntax: the scope for resolving ambiguities via type-inference is
  3352 now limited to individual terms, instead of whole simultaneous
  3353 specifications as before. This greatly reduces the complexity of the
  3354 syntax module and improves flexibility by separating parsing and
  3355 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3356 'fixes' etc.) are required in rare situations.
  3357 
  3358 * Syntax: constants introduced by new-style packages ('definition',
  3359 'abbreviation' etc.) are passed through the syntax module in
  3360 ``authentic mode''. This means that associated mixfix annotations
  3361 really stick to such constants, independently of potential name space
  3362 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3363 trees are represented slightly differently, may need to adapt syntax
  3364 translations accordingly. Use CONST marker in 'translations' and
  3365 @{const_syntax} antiquotation in 'parse_translation' etc.
  3366 
  3367 * Legacy goal package: reduced interface to the bare minimum required
  3368 to keep existing proof scripts running.  Most other user-level
  3369 functions are now part of the OldGoals structure, which is *not* open
  3370 by default (consider isatool expandshort before open OldGoals).
  3371 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3372 these tend to cause confusion about the actual goal (!) context being
  3373 used here, which is not necessarily the same as the_context().
  3374 
  3375 * Command 'find_theorems': supports "*" wild-card in "name:"
  3376 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3377 support a specific search form (see ProofGeneral/CHANGES).
  3378 
  3379 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3380 by default, which means that "prems" (and also "fixed variables") are
  3381 suppressed from proof state output.  Note that the ProofGeneral
  3382 settings mechanism allows to change and save options persistently, but
  3383 older versions of Isabelle will fail to start up if a negative prems
  3384 limit is imposed.
  3385 
  3386 * Local theory targets may be specified by non-nested blocks of
  3387 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3388 contain definitions, theorems etc., including any derived mechanism
  3389 that has been implemented on top of these primitives.  This concept
  3390 generalizes the existing ``theorem (in ...)'' towards more versatility
  3391 and scalability.
  3392 
  3393 * Proof General interface: proper undo of final 'end' command;
  3394 discontinued Isabelle/classic mode (ML proof scripts).
  3395 
  3396 
  3397 *** Document preparation ***
  3398 
  3399 * Added antiquotation @{theory name} which prints the given name,
  3400 after checking that it refers to a valid ancestor theory in the
  3401 current context.
  3402 
  3403 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3404 check the given source text as ML type/structure, printing verbatim.
  3405 
  3406 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3407 "c args == rhs" given in the current context.  (Any number of
  3408 arguments may be given on the LHS.)
  3409 
  3410 
  3411 *** Pure ***
  3412 
  3413 * The 'class' package offers a combination of axclass and locale to
  3414 achieve Haskell-like type classes in Isabelle.  Definitions and
  3415 theorems within a class context produce both relative results (with
  3416 implicit parameters according to the locale context), and polymorphic
  3417 constants with qualified polymorphism (according to the class
  3418 context).  Within the body context of a 'class' target, a separate
  3419 syntax layer ("user space type system") takes care of converting
  3420 between global polymorphic consts and internal locale representation.
  3421 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3422 "isatool doc classes" provides a tutorial.
  3423 
  3424 * Generic code generator framework allows to generate executable
  3425 code for ML and Haskell (including Isabelle classes).  A short usage
  3426 sketch:
  3427 
  3428     internal compilation:
  3429         export_code <list of constants (term syntax)> in SML
  3430     writing SML code to a file:
  3431         export_code <list of constants (term syntax)> in SML <filename>
  3432     writing OCaml code to a file:
  3433         export_code <list of constants (term syntax)> in OCaml <filename>
  3434     writing Haskell code to a bunch of files:
  3435         export_code <list of constants (term syntax)> in Haskell <filename>
  3436 
  3437     evaluating closed propositions to True/False using code generation:
  3438         method ``eval''
  3439 
  3440 Reasonable default setup of framework in HOL.
  3441 
  3442 Theorem attributs for selecting and transforming function equations theorems:
  3443 
  3444     [code fun]:        select a theorem as function equation for a specific constant
  3445     [code fun del]:    deselect a theorem as function equation for a specific constant
  3446     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3447     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3448 
  3449 User-defined serializations (target in {SML, OCaml, Haskell}):
  3450 
  3451     code_const <and-list of constants (term syntax)>
  3452       {(target) <and-list of const target syntax>}+
  3453 
  3454     code_type <and-list of type constructors>
  3455       {(target) <and-list of type target syntax>}+
  3456 
  3457     code_instance <and-list of instances>
  3458       {(target)}+
  3459         where instance ::= <type constructor> :: <class>
  3460 
  3461     code_class <and_list of classes>
  3462       {(target) <and-list of class target syntax>}+
  3463         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3464 
  3465 code_instance and code_class only are effective to target Haskell.
  3466 
  3467 For example usage see src/HOL/ex/Codegenerator.thy and
  3468 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3469 generation from Isabelle/HOL theories is available via "isatool doc
  3470 codegen".
  3471 
  3472 * Code generator: consts in 'consts_code' Isar commands are now
  3473 referred to by usual term syntax (including optional type
  3474 annotations).
  3475 
  3476 * Command 'no_translations' removes translation rules from theory
  3477 syntax.
  3478 
  3479 * Overloaded definitions are now actually checked for acyclic
  3480 dependencies.  The overloading scheme is slightly more general than
  3481 that of Haskell98, although Isabelle does not demand an exact
  3482 correspondence to type class and instance declarations.
  3483 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3484 exotic versions of overloading -- at the discretion of the user!
  3485 
  3486 Polymorphic constants are represented via type arguments, i.e. the
  3487 instantiation that matches an instance against the most general
  3488 declaration given in the signature.  For example, with the declaration
  3489 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3490 as c(nat).  Overloading is essentially simultaneous structural
  3491 recursion over such type arguments.  Incomplete specification patterns
  3492 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3493 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3494 Command 'print_theory' outputs the normalized system of recursive
  3495 equations, see section "definitions".
  3496 
  3497 * Configuration options are maintained within the theory or proof
  3498 context (with name and type bool/int/string), providing a very simple
  3499 interface to a poor-man's version of general context data.  Tools may
  3500 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3501 these values using Config.get etc.  Users may change options via an
  3502 associated attribute of the same name.  This form of context
  3503 declaration works particularly well with commands 'declare' or
  3504 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3505 very easy to avoid global references, which would not observe Isar
  3506 toplevel undo/redo and fail to work with multithreading.
  3507 
  3508 Various global ML references of Pure and HOL have been turned into
  3509 configuration options:
  3510 
  3511   Unify.search_bound		unify_search_bound
  3512   Unify.trace_bound		unify_trace_bound
  3513   Unify.trace_simp		unify_trace_simp
  3514   Unify.trace_types		unify_trace_types
  3515   Simplifier.simp_depth_limit	simp_depth_limit
  3516   Blast.depth_limit		blast_depth_limit
  3517   DatatypeProp.dtK		datatype_distinctness_limit
  3518   fast_arith_neq_limit  	fast_arith_neq_limit
  3519   fast_arith_split_limit	fast_arith_split_limit
  3520 
  3521 * Named collections of theorems may be easily installed as context
  3522 data using the functor NamedThmsFun (see also
  3523 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3524 attributes; there is also a toplevel print command.  This facility is
  3525 just a common case of general context data, which is the preferred way
  3526 for anything more complex than just a list of facts in canonical
  3527 order.
  3528 
  3529 * Isar: command 'declaration' augments a local theory by generic
  3530 declaration functions written in ML.  This enables arbitrary content
  3531 being added to the context, depending on a morphism that tells the
  3532 difference of the original declaration context wrt. the application
  3533 context encountered later on.
  3534 
  3535 * Isar: proper interfaces for simplification procedures.  Command
  3536 'simproc_setup' declares named simprocs (with match patterns, and body
  3537 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3538 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3539 
  3540 * Isar: an extra pair of brackets around attribute declarations
  3541 abbreviates a theorem reference involving an internal dummy fact,
  3542 which will be ignored later --- only the effect of the attribute on
  3543 the background context will persist.  This form of in-place
  3544 declarations is particularly useful with commands like 'declare' and
  3545 'using', for example ``have A using [[simproc a]] by simp''.
  3546 
  3547 * Isar: method "assumption" (and implicit closing of subproofs) now
  3548 takes simple non-atomic goal assumptions into account: after applying
  3549 an assumption as a rule the resulting subgoals are solved by atomic
  3550 assumption steps.  This is particularly useful to finish 'obtain'
  3551 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3552 without referring to the original premise "!!x. P x ==> thesis" in the
  3553 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3554 more permissive.
  3555 
  3556 * Isar: implicit use of prems from the Isar proof context is
  3557 considered a legacy feature.  Common applications like ``have A .''
  3558 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3559 referencing facts explicitly here improves readability and
  3560 maintainability of proof texts.
  3561 
  3562 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3563 the obtained context from the course of reasoning!  For example:
  3564 
  3565   assume "EX x y. A x & B y"   -- "any previous fact"
  3566   then guess x and y by clarify
  3567 
  3568 This technique is potentially adventurous, depending on the facts and
  3569 proof tools being involved here.
  3570 
  3571 * Isar: known facts from the proof context may be specified as literal
  3572 propositions, using ASCII back-quote syntax.  This works wherever
  3573 named facts used to be allowed so far, in proof commands, proof
  3574 methods, attributes etc.  Literal facts are retrieved from the context
  3575 according to unification of type and term parameters.  For example,
  3576 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3577 theorems in the current context, then these are valid literal facts:
  3578 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3579 
  3580 There is also a proof method "fact" which does the same composition
  3581 for explicit goal states, e.g. the following proof texts coincide with
  3582 certain special cases of literal facts:
  3583 
  3584   have "A" by fact                 ==  note `A`
  3585   have "A ==> B" by fact           ==  note `A ==> B`
  3586   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3587   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3588 
  3589 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3590 outer syntax.  Thus symbolic identifiers may be used without
  3591 additional white space in declarations like this: ``assume *: A''.
  3592 
  3593 * Isar: 'print_facts' prints all local facts of the current context,
  3594 both named and unnamed ones.
  3595 
  3596 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3597 
  3598   def x == "t" and y == "u"
  3599 
  3600 * Isar: added command 'unfolding', which is structurally similar to
  3601 'using', but affects both the goal state and facts by unfolding given
  3602 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3603 'unfolded' attribute may be replaced by first-class proof text.
  3604 
  3605 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3606 and command 'unfolding' now all support object-level equalities
  3607 (potentially conditional).  The underlying notion of rewrite rule is
  3608 analogous to the 'rule_format' attribute, but *not* that of the
  3609 Simplifier (which is usually more generous).
  3610 
  3611 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3612 premises of a theorem by n. Useful in conjunction with drule.
  3613 
  3614 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3615 method expression within a sandbox consisting of the first N
  3616 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3617 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3618 simplifies all new goals that emerge from applying rule foo to the
  3619 originally first one.
  3620 
  3621 * Isar: schematic goals are no longer restricted to higher-order
  3622 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3623 expected.
  3624 
  3625 * Isar: the conclusion of a long theorem statement is now either
  3626 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3627 (essentially a disjunction of cases with local parameters and
  3628 assumptions).  The latter allows to express general elimination rules
  3629 adequately; in this notation common elimination rules look like this:
  3630 
  3631   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3632     assumes "EX x. P x"
  3633     obtains x where "P x"
  3634 
  3635   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3636     assumes "A & B"
  3637     obtains A and B
  3638 
  3639   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3640     assumes "A | B"
  3641     obtains
  3642       A
  3643     | B
  3644 
  3645 The subsequent classical rules even refer to the formal "thesis"
  3646 explicitly:
  3647 
  3648   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3649     obtains "~ thesis"
  3650 
  3651   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3652     obtains "thesis ==> something"
  3653 
  3654 The actual proof of an 'obtains' statement is analogous to that of the
  3655 Isar proof element 'obtain', only that there may be several cases.
  3656 Optional case names may be specified in parentheses; these will be
  3657 available both in the present proof and as annotations in the
  3658 resulting rule, for later use with the 'cases' method (cf. attribute
  3659 case_names).
  3660 
  3661 * Isar: the assumptions of a long theorem statement are available as
  3662 "assms" fact in the proof context.  This is more appropriate than the
  3663 (historical) "prems", which refers to all assumptions of the current
  3664 context, including those from the target locale, proof body etc.
  3665 
  3666 * Isar: 'print_statement' prints theorems from the current theory or
  3667 proof context in long statement form, according to the syntax of a
  3668 top-level lemma.
  3669 
  3670 * Isar: 'obtain' takes an optional case name for the local context
  3671 introduction rule (default "that").
  3672 
  3673 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3674 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3675 to occur.
  3676 
  3677 * Pure: syntax "CONST name" produces a fully internalized constant
  3678 according to the current context.  This is particularly useful for
  3679 syntax translations that should refer to internal constant
  3680 representations independently of name spaces.
  3681 
  3682 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3683 instead of "FOO ". This allows multiple binder declarations to coexist
  3684 in the same context.  INCOMPATIBILITY.
  3685 
  3686 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3687 primitive that also works in a locale context (both for constants and
  3688 fixed variables). Type declaration and internal syntactic representation
  3689 of given constants retrieved from the context. Likewise, the
  3690 'no_notation' command allows to remove given syntax annotations from the
  3691 current context.
  3692 
  3693 * Isar/locales: new derived specification elements 'axiomatization',
  3694 'definition', 'abbreviation', which support type-inference, admit
  3695 object-level specifications (equality, equivalence).  See also the
  3696 isar-ref manual.  Examples:
  3697 
  3698   axiomatization
  3699     eq  (infix "===" 50) where
  3700     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3701 
  3702   definition "f x y = x + y + 1"
  3703   definition g where "g x = f x x"
  3704 
  3705   abbreviation
  3706     neq  (infix "=!=" 50) where
  3707     "x =!= y == ~ (x === y)"
  3708 
  3709 These specifications may be also used in a locale context.  Then the
  3710 constants being introduced depend on certain fixed parameters, and the
  3711 constant name is qualified by the locale base name.  An internal
  3712 abbreviation takes care for convenient input and output, making the
  3713 parameters implicit and using the original short name.  See also
  3714 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3715 entities from a monomorphic theory.
  3716 
  3717 Presently, abbreviations are only available 'in' a target locale, but
  3718 not inherited by general import expressions.  Also note that
  3719 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3720 'translations' in common applications.  The "no_abbrevs" print mode
  3721 prevents folding of abbreviations in term output.
  3722 
  3723 Concrete syntax is attached to specified constants in internal form,
  3724 independently of name spaces.  The parse tree representation is
  3725 slightly different -- use 'notation' instead of raw 'syntax', and
  3726 'translations' with explicit "CONST" markup to accommodate this.
  3727 
  3728 * Pure/Isar: unified syntax for new-style specification mechanisms
  3729 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3730 full type inference and dummy patterns ("_").  For example:
  3731 
  3732   definition "K x _ = x"
  3733 
  3734   inductive conj for A B
  3735   where "A ==> B ==> conj A B"
  3736 
  3737 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3738 the current context.  Print mode "no_abbrevs" prevents inversion of
  3739 abbreviations on output.
  3740 
  3741 * Isar/locales: improved parameter handling: use of locales "var" and
  3742 "struct" no longer necessary; - parameter renamings are no longer
  3743 required to be injective.  For example, this allows to define
  3744 endomorphisms as locale endom = homom mult mult h.
  3745 
  3746 * Isar/locales: changed the way locales with predicates are defined.
  3747 Instead of accumulating the specification, the imported expression is
  3748 now an interpretation.  INCOMPATIBILITY: different normal form of
  3749 locale expressions.  In particular, in interpretations of locales with
  3750 predicates, goals repesenting already interpreted fragments are not
  3751 removed automatically.  Use methods `intro_locales' and
  3752 `unfold_locales'; see below.
  3753 
  3754 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3755 provide backward reasoning on locales predicates.  The methods are
  3756 aware of interpretations and discharge corresponding goals.
  3757 `intro_locales' is less aggressive then `unfold_locales' and does not
  3758 unfold predicates to assumptions.
  3759 
  3760 * Isar/locales: the order in which locale fragments are accumulated
  3761 has changed.  This enables to override declarations from fragments due
  3762 to interpretations -- for example, unwanted simp rules.
  3763 
  3764 * Isar/locales: interpretation in theories and proof contexts has been
  3765 extended.  One may now specify (and prove) equations, which are
  3766 unfolded in interpreted theorems.  This is useful for replacing
  3767 defined concepts (constants depending on locale parameters) by
  3768 concepts already existing in the target context.  Example:
  3769 
  3770   interpretation partial_order ["op <= :: [int, int] => bool"]
  3771     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3772 
  3773 Typically, the constant `partial_order.less' is created by a
  3774 definition specification element in the context of locale
  3775 partial_order.
  3776 
  3777 * Method "induct": improved internal context management to support
  3778 local fixes and defines on-the-fly. Thus explicit meta-level
  3779 connectives !!  and ==> are rarely required anymore in inductive goals
  3780 (using object-logic connectives for this purpose has been long
  3781 obsolete anyway). Common proof patterns are explained in
  3782 src/HOL/Induct/Common_Patterns.thy, see also
  3783 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3784 examples.
  3785 
  3786 * Method "induct": improved handling of simultaneous goals. Instead of
  3787 introducing object-level conjunction, the statement is now split into
  3788 several conclusions, while the corresponding symbolic cases are nested
  3789 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3790 see src/HOL/Induct/Common_Patterns.thy, for example.
  3791 
  3792 * Method "induct": mutual induction rules are now specified as a list
  3793 of rule sharing the same induction cases. HOL packages usually provide
  3794 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3795 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3796 mutual induction rules differently, i.e. like this:
  3797 
  3798   (induct rule: foo_bar.inducts)
  3799   (induct set: foo bar)
  3800   (induct pred: foo bar)
  3801   (induct type: foo bar)
  3802 
  3803 The ML function ProjectRule.projections turns old-style rules into the
  3804 new format.
  3805 
  3806 * Method "coinduct": dual of induction, see
  3807 src/HOL/Library/Coinductive_List.thy for various examples.
  3808 
  3809 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3810 considered a legacy feature.
  3811 
  3812 * Attribute "symmetric" produces result with standardized schematic
  3813 variables (index 0).  Potential INCOMPATIBILITY.
  3814 
  3815 * Simplifier: by default the simplifier trace only shows top level
  3816 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3817 default. Thus there is less danger of being flooded by the trace. The
  3818 trace indicates where parts have been suppressed.
  3819   
  3820 * Provers/classical: removed obsolete classical version of elim_format
  3821 attribute; classical elim/dest rules are now treated uniformly when
  3822 manipulating the claset.
  3823 
  3824 * Provers/classical: stricter checks to ensure that supplied intro,
  3825 dest and elim rules are well-formed; dest and elim rules must have at
  3826 least one premise.
  3827 
  3828 * Provers/classical: attributes dest/elim/intro take an optional
  3829 weight argument for the rule (just as the Pure versions).  Weights are
  3830 ignored by automated tools, but determine the search order of single
  3831 rule steps.
  3832 
  3833 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3834 where the body does not mention the bound variable.  Note that dummy
  3835 patterns implicitly depend on their context of bounds, which makes
  3836 "{_. _}" match any set comprehension as expected.  Potential
  3837 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3838 constant "_idtdummy" in the binding position.
  3839 
  3840 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3841 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3842 for example "A -> B" => "Pi A (%_. B)".
  3843 
  3844 * Pure: 'class_deps' command visualizes the subclass relation, using
  3845 the graph browser tool.
  3846 
  3847 * Pure: 'print_theory' now suppresses certain internal declarations by
  3848 default; use '!' option for full details.
  3849 
  3850 
  3851 *** HOL ***
  3852 
  3853 * Method "metis" proves goals by applying the Metis general-purpose
  3854 resolution prover (see also http://gilith.com/software/metis/).
  3855 Examples are in the directory MetisExamples.  WARNING: the
  3856 Isabelle/HOL-Metis integration does not yet work properly with
  3857 multi-threading.
  3858   
  3859 * Command 'sledgehammer' invokes external automatic theorem provers as
  3860 background processes.  It generates calls to the "metis" method if
  3861 successful. These can be pasted into the proof.  Users do not have to
  3862 wait for the automatic provers to return.  WARNING: does not really
  3863 work with multi-threading.
  3864 
  3865 * New "auto_quickcheck" feature tests outermost goal statements for
  3866 potential counter-examples.  Controlled by ML references
  3867 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3868 5000 milliseconds).  Fails silently if statements is outside of
  3869 executable fragment, or any other codgenerator problem occurs.
  3870 
  3871 * New constant "undefined" with axiom "undefined x = undefined".
  3872 
  3873 * Added class "HOL.eq", allowing for code generation with polymorphic
  3874 equality.
  3875 
  3876 * Some renaming of class constants due to canonical name prefixing in
  3877 the new 'class' package:
  3878 
  3879     HOL.abs ~> HOL.abs_class.abs
  3880     HOL.divide ~> HOL.divide_class.divide
  3881     0 ~> HOL.zero_class.zero
  3882     1 ~> HOL.one_class.one
  3883     op + ~> HOL.plus_class.plus
  3884     op - ~> HOL.minus_class.minus
  3885     uminus ~> HOL.minus_class.uminus
  3886     op * ~> HOL.times_class.times
  3887     op < ~> HOL.ord_class.less
  3888     op <= > HOL.ord_class.less_eq
  3889     Nat.power ~> Power.power_class.power
  3890     Nat.size ~> Nat.size_class.size
  3891     Numeral.number_of ~> Numeral.number_class.number_of
  3892     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3893     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3894     Orderings.min ~> Orderings.ord_class.min
  3895     Orderings.max ~> Orderings.ord_class.max
  3896     Divides.op div ~> Divides.div_class.div
  3897     Divides.op mod ~> Divides.div_class.mod
  3898     Divides.op dvd ~> Divides.div_class.dvd
  3899 
  3900 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3901 
  3902 a) User-defined constants using any of the names "plus", "minus",
  3903 "times", "less" or "less_eq". The standard syntax translations for
  3904 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3905 names.
  3906 
  3907 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3908 INCOMPATIBILITY: use more specific names.
  3909 
  3910 c) Permutative equations (e.g. "a + b = b + a")
  3911 Since the change of names also changes the order of terms, permutative
  3912 rewrite rules may get applied in a different order. Experience shows
  3913 that this is rarely the case (only two adaptions in the whole Isabelle
  3914 distribution).  INCOMPATIBILITY: rewrite proofs
  3915 
  3916 d) ML code directly refering to constant names
  3917 This in general only affects hand-written proof tactics, simprocs and
  3918 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3919 Consider using @{const_name} antiquotation.
  3920 
  3921 * New class "default" with associated constant "default".
  3922 
  3923 * Function "sgn" is now overloaded and available on int, real, complex
  3924 (and other numeric types), using class "sgn".  Two possible defs of
  3925 sgn are given as equational assumptions in the classes sgn_if and
  3926 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3927 INCOMPATIBILITY.
  3928 
  3929 * Locale "partial_order" now unified with class "order" (cf. theory
  3930 Orderings), added parameter "less".  INCOMPATIBILITY.
  3931 
  3932 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3933 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3934 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3935 
  3936 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3937 changed order of proof goals in instance proofs.
  3938 
  3939 * The transitivity reasoner for partial and linear orders is set up
  3940 for classes "order" and "linorder".  Instances of the reasoner are available
  3941 in all contexts importing or interpreting the corresponding locales.
  3942 Method "order" invokes the reasoner separately; the reasoner
  3943 is also integrated with the Simplifier as a solver.  Diagnostic
  3944 command 'print_orders' shows the available instances of the reasoner
  3945 in the current context.
  3946 
  3947 * Localized monotonicity predicate in theory "Orderings"; integrated
  3948 lemmas max_of_mono and min_of_mono with this predicate.
  3949 INCOMPATIBILITY.
  3950 
  3951 * Formulation of theorem "dense" changed slightly due to integration
  3952 with new class dense_linear_order.
  3953 
  3954 * Uniform lattice theory development in HOL.
  3955 
  3956     constants "meet" and "join" now named "inf" and "sup"
  3957     constant "Meet" now named "Inf"
  3958 
  3959     classes "meet_semilorder" and "join_semilorder" now named
  3960       "lower_semilattice" and "upper_semilattice"
  3961     class "lorder" now named "lattice"
  3962     class "comp_lat" now named "complete_lattice"
  3963 
  3964     Instantiation of lattice classes allows explicit definitions
  3965     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3966 
  3967   INCOMPATIBILITY.  Theorem renames:
  3968 
  3969     meet_left_le            ~> inf_le1
  3970     meet_right_le           ~> inf_le2
  3971     join_left_le            ~> sup_ge1
  3972     join_right_le           ~> sup_ge2
  3973     meet_join_le            ~> inf_sup_ord
  3974     le_meetI                ~> le_infI
  3975     join_leI                ~> le_supI
  3976     le_meet                 ~> le_inf_iff
  3977     le_join                 ~> ge_sup_conv
  3978     meet_idempotent         ~> inf_idem
  3979     join_idempotent         ~> sup_idem
  3980     meet_comm               ~> inf_commute
  3981     join_comm               ~> sup_commute
  3982     meet_leI1               ~> le_infI1
  3983     meet_leI2               ~> le_infI2
  3984     le_joinI1               ~> le_supI1
  3985     le_joinI2               ~> le_supI2
  3986     meet_assoc              ~> inf_assoc
  3987     join_assoc              ~> sup_assoc
  3988     meet_left_comm          ~> inf_left_commute
  3989     meet_left_idempotent    ~> inf_left_idem
  3990     join_left_comm          ~> sup_left_commute
  3991     join_left_idempotent    ~> sup_left_idem
  3992     meet_aci                ~> inf_aci
  3993     join_aci                ~> sup_aci
  3994     le_def_meet             ~> le_iff_inf
  3995     le_def_join             ~> le_iff_sup
  3996     join_absorp2            ~> sup_absorb2
  3997     join_absorp1            ~> sup_absorb1
  3998     meet_absorp1            ~> inf_absorb1
  3999     meet_absorp2            ~> inf_absorb2
  4000     meet_join_absorp        ~> inf_sup_absorb
  4001     join_meet_absorp        ~> sup_inf_absorb
  4002     distrib_join_le         ~> distrib_sup_le
  4003     distrib_meet_le         ~> distrib_inf_le
  4004 
  4005     add_meet_distrib_left   ~> add_inf_distrib_left
  4006     add_join_distrib_left   ~> add_sup_distrib_left
  4007     is_join_neg_meet        ~> is_join_neg_inf
  4008     is_meet_neg_join        ~> is_meet_neg_sup
  4009     add_meet_distrib_right  ~> add_inf_distrib_right
  4010     add_join_distrib_right  ~> add_sup_distrib_right
  4011     add_meet_join_distribs  ~> add_sup_inf_distribs
  4012     join_eq_neg_meet        ~> sup_eq_neg_inf
  4013     meet_eq_neg_join        ~> inf_eq_neg_sup
  4014     add_eq_meet_join        ~> add_eq_inf_sup
  4015     meet_0_imp_0            ~> inf_0_imp_0
  4016     join_0_imp_0            ~> sup_0_imp_0
  4017     meet_0_eq_0             ~> inf_0_eq_0
  4018     join_0_eq_0             ~> sup_0_eq_0
  4019     neg_meet_eq_join        ~> neg_inf_eq_sup
  4020     neg_join_eq_meet        ~> neg_sup_eq_inf
  4021     join_eq_if              ~> sup_eq_if
  4022 
  4023     mono_meet               ~> mono_inf
  4024     mono_join               ~> mono_sup
  4025     meet_bool_eq            ~> inf_bool_eq
  4026     join_bool_eq            ~> sup_bool_eq
  4027     meet_fun_eq             ~> inf_fun_eq
  4028     join_fun_eq             ~> sup_fun_eq
  4029     meet_set_eq             ~> inf_set_eq
  4030     join_set_eq             ~> sup_set_eq
  4031     meet1_iff               ~> inf1_iff
  4032     meet2_iff               ~> inf2_iff
  4033     meet1I                  ~> inf1I
  4034     meet2I                  ~> inf2I
  4035     meet1D1                 ~> inf1D1
  4036     meet2D1                 ~> inf2D1
  4037     meet1D2                 ~> inf1D2
  4038     meet2D2                 ~> inf2D2
  4039     meet1E                  ~> inf1E
  4040     meet2E                  ~> inf2E
  4041     join1_iff               ~> sup1_iff
  4042     join2_iff               ~> sup2_iff
  4043     join1I1                 ~> sup1I1
  4044     join2I1                 ~> sup2I1
  4045     join1I1                 ~> sup1I1
  4046     join2I2                 ~> sup1I2
  4047     join1CI                 ~> sup1CI
  4048     join2CI                 ~> sup2CI
  4049     join1E                  ~> sup1E
  4050     join2E                  ~> sup2E
  4051 
  4052     is_meet_Meet            ~> is_meet_Inf
  4053     Meet_bool_def           ~> Inf_bool_def
  4054     Meet_fun_def            ~> Inf_fun_def
  4055     Meet_greatest           ~> Inf_greatest
  4056     Meet_lower              ~> Inf_lower
  4057     Meet_set_def            ~> Inf_set_def
  4058 
  4059     Sup_def                 ~> Sup_Inf
  4060     Sup_bool_eq             ~> Sup_bool_def
  4061     Sup_fun_eq              ~> Sup_fun_def
  4062     Sup_set_eq              ~> Sup_set_def
  4063 
  4064     listsp_meetI            ~> listsp_infI
  4065     listsp_meet_eq          ~> listsp_inf_eq
  4066 
  4067     meet_min                ~> inf_min
  4068     join_max                ~> sup_max
  4069 
  4070 * Added syntactic class "size"; overloaded constant "size" now has
  4071 type "'a::size ==> bool"
  4072 
  4073 * Internal reorganisation of `size' of datatypes: size theorems
  4074 "foo.size" are no longer subsumed by "foo.simps" (but are still
  4075 simplification rules by default!); theorems "prod.size" now named
  4076 "*.size".
  4077 
  4078 * Class "div" now inherits from class "times" rather than "type".
  4079 INCOMPATIBILITY.
  4080 
  4081 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  4082 Linorder etc.  have disappeared; operations defined in terms of
  4083 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  4084 
  4085 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  4086 
  4087 * HOL-Word: New extensive library and type for generic, fixed size
  4088 machine words, with arithemtic, bit-wise, shifting and rotating
  4089 operations, reflection into int, nat, and bool lists, automation for
  4090 linear arithmetic (by automatic reflection into nat or int), including
  4091 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  4092 arithmetic type classes, supporting automatic simplification of
  4093 numerals on all operations.
  4094 
  4095 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  4096 
  4097 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  4098 
  4099 * Code generator library theories:
  4100   - Code_Integer represents HOL integers by big integer literals in target
  4101     languages.
  4102   - Code_Char represents HOL characters by character literals in target
  4103     languages.
  4104   - Code_Char_chr like Code_Char, but also offers treatment of character
  4105     codes; includes Code_Integer.
  4106   - Executable_Set allows to generate code for finite sets using lists.
  4107   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  4108     denominator).
  4109   - Executable_Real implements a subset of real numbers, namly those
  4110     representable by rational numbers.
  4111   - Efficient_Nat implements natural numbers by integers, which in general will
  4112     result in higher efficency; pattern matching with 0/Suc is eliminated;
  4113     includes Code_Integer.
  4114   - Code_Index provides an additional datatype index which is mapped to
  4115     target-language built-in integers.
  4116   - Code_Message provides an additional datatype message_string which is isomorphic to
  4117     strings; messages are mapped to target-language strings.
  4118 
  4119 * New package for inductive predicates
  4120 
  4121   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  4122 
  4123     inductive
  4124       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4125       for z_1 :: U_1 and ... and z_n :: U_m
  4126     where
  4127       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4128     | ...
  4129 
  4130   with full support for type-inference, rather than
  4131 
  4132     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4133 
  4134     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4135     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4136 
  4137     inductive "s z_1 ... z_m"
  4138     intros
  4139       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4140       ...
  4141 
  4142   For backward compatibility, there is a wrapper allowing inductive
  4143   sets to be defined with the new package via
  4144 
  4145     inductive_set
  4146       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4147       for z_1 :: U_1 and ... and z_n :: U_m
  4148     where
  4149       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4150     | ...
  4151 
  4152   or
  4153 
  4154     inductive_set
  4155       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4156       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4157       for z_1 :: U_1 and ... and z_n :: U_m
  4158     where
  4159       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4160     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4161     | ...
  4162 
  4163   if the additional syntax "p ..." is required.
  4164 
  4165   Numerous examples can be found in the subdirectories src/HOL/Auth,
  4166   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  4167 
  4168   INCOMPATIBILITIES:
  4169 
  4170   - Since declaration and definition of inductive sets or predicates
  4171     is no longer separated, abbreviations involving the newly
  4172     introduced sets or predicates must be specified together with the
  4173     introduction rules after the 'where' keyword (see above), rather
  4174     than before the actual inductive definition.
  4175 
  4176   - The variables in induction and elimination rules are now
  4177     quantified in the order of their occurrence in the introduction
  4178     rules, rather than in alphabetical order. Since this may break
  4179     some proofs, these proofs either have to be repaired, e.g. by
  4180     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  4181     statements of the form
  4182 
  4183       case (rule_i a_i_1 ... a_i_{k_i})
  4184 
  4185     or the old order of quantification has to be restored by explicitly adding
  4186     meta-level quantifiers in the introduction rules, i.e.
  4187 
  4188       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  4189 
  4190   - The format of the elimination rules is now
  4191 
  4192       p z_1 ... z_m x_1 ... x_n ==>
  4193         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4194         ==> ... ==> P
  4195 
  4196     for predicates and
  4197 
  4198       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4199         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4200         ==> ... ==> P
  4201 
  4202     for sets rather than
  4203 
  4204       x : s z_1 ... z_m ==>
  4205         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4206         ==> ... ==> P
  4207 
  4208     This may require terms in goals to be expanded to n-tuples
  4209     (e.g. using case_tac or simplification with the split_paired_all
  4210     rule) before the above elimination rule is applicable.
  4211 
  4212   - The elimination or case analysis rules for (mutually) inductive
  4213     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4214     list of rules "p_1_..._p_k.elims" is no longer available.
  4215 
  4216 * New package "function"/"fun" for general recursive functions,
  4217 supporting mutual and nested recursion, definitions in local contexts,
  4218 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4219 for small examples, and the separate tutorial on the function
  4220 package. The old recdef "package" is still available as before, but
  4221 users are encouraged to use the new package.
  4222 
  4223 * Method "lexicographic_order" automatically synthesizes termination
  4224 relations as lexicographic combinations of size measures. 
  4225 
  4226 * Case-expressions allow arbitrary constructor-patterns (including
  4227 "_") and take their order into account, like in functional
  4228 programming.  Internally, this is translated into nested
  4229 case-expressions; missing cases are added and mapped to the predefined
  4230 constant "undefined". In complicated cases printing may no longer show
  4231 the original input but the internal form. Lambda-abstractions allow
  4232 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4233 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4234 variable.
  4235 
  4236 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4237 is an abbreviation for "of_nat :: nat => int". The simplification
  4238 rules for "of_nat" have been changed to work like "int" did
  4239 previously.  Potential INCOMPATIBILITY:
  4240   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4241   - of_nat_diff and of_nat_mult are no longer default simp rules
  4242 
  4243 * Method "algebra" solves polynomial equations over (semi)rings using
  4244 Groebner bases. The (semi)ring structure is defined by locales and the
  4245 tool setup depends on that generic context. Installing the method for
  4246 a specific type involves instantiating the locale and possibly adding
  4247 declarations for computation on the coefficients.  The method is
  4248 already instantiated for natural numbers and for the axiomatic class
  4249 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4250 CALCULEMUS 2007 for the general principles underlying this
  4251 architecture of context-aware proof-tools.
  4252 
  4253 * Method "ferrack" implements quantifier elimination over
  4254 special-purpose dense linear orders using locales (analogous to
  4255 "algebra"). The method is already installed for class
  4256 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4257 rat, etc.
  4258 
  4259 * Former constant "List.op @" now named "List.append".  Use ML
  4260 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4261 circumvent possible incompatibilities when working on ML level.
  4262 
  4263 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4264 
  4265 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4266 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4267 
  4268 * New syntax for Haskell-like list comprehension (input only), eg.
  4269 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4270 
  4271 * The special syntax for function "filter" has changed from [x :
  4272 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4273 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4274 
  4275 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4276 defined on nat only, as an abbreviation for [a..<Suc b]
  4277 INCOMPATIBILITY.
  4278 
  4279 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4280 
  4281 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4282 
  4283 * New lemma collection field_simps (an extension of ring_simps) for
  4284 manipulating (in)equations involving division. Multiplies with all
  4285 denominators that can be proved to be non-zero (in equations) or
  4286 positive/negative (in inequations).
  4287 
  4288 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4289 have been improved and renamed to ring_simps, group_simps and
  4290 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4291 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4292 
  4293 * Theory Library/Commutative_Ring: switched from recdef to function
  4294 package; constants add, mul, pow now curried.  Infix syntax for
  4295 algebraic operations.
  4296 
  4297 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4298 INCOMPATIBILITY.
  4299 
  4300 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4301 INCOMPATIBILITY.
  4302 
  4303 * HOL/records: generalised field-update to take a function on the
  4304 field rather than the new value: r(|A := x|) is translated to A_update
  4305 (K x) r The K-combinator that is internally used is called K_record.
  4306 INCOMPATIBILITY: Usage of the plain update functions has to be
  4307 adapted.
  4308  
  4309 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4310 * x = 0, which are required for a semiring.  Richer structures do not
  4311 inherit from semiring_0 anymore, because this property is a theorem
  4312 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4313 there is more to prove, but this is mostly trivial.
  4314 
  4315 * Class "recpower" is generalized to arbitrary monoids, not just
  4316 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4317 commutativity or semiring properties additionally.
  4318 
  4319 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4320 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4321 better use 'abbreviation'.
  4322 
  4323 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4324 
  4325 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4326 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4327 significant changes for setting up numeral syntax for types:
  4328   - New constants Numeral.pred and Numeral.succ instead
  4329       of former Numeral.bin_pred and Numeral.bin_succ.
  4330   - Use integer operations instead of bin_add, bin_mult and so on.
  4331   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4332   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4333 
  4334 See src/HOL/Integ/IntArith.thy for an example setup.
  4335 
  4336 * Command 'normal_form' computes the normal form of a term that may
  4337 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4338 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4339 heavy-duty computations because the functions are compiled to ML
  4340 first.  Correspondingly, a method "normalization" is provided.  See
  4341 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4342 
  4343 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4344 25 like -->); output depends on the "iff" print_mode, the default is
  4345 "A = B" (with priority 50).
  4346 
  4347 * Relations less (<) and less_eq (<=) are also available on type bool.
  4348 Modified syntax to disallow nesting without explicit parentheses,
  4349 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4350 INCOMPATIBILITY.
  4351 
  4352 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4353 
  4354 * Relation composition operator "op O" now has precedence 75 and binds
  4355 stronger than union and intersection. INCOMPATIBILITY.
  4356 
  4357 * The old set interval syntax "{m..n(}" (and relatives) has been
  4358 removed.  Use "{m..<n}" (and relatives) instead.
  4359 
  4360 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4361 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4362 ``declare [[simproc del: neq]]''.
  4363 
  4364 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4365 True/False.
  4366 
  4367 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4368 
  4369 * Theorem setsum_mult renamed to setsum_right_distrib.
  4370 
  4371 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4372 ``rule'' method.
  4373 
  4374 * Reimplemented methods "sat" and "satx", with several improvements:
  4375 goals no longer need to be stated as "<prems> ==> False", equivalences
  4376 (i.e. "=" on type bool) are handled, variable names of the form
  4377 "lit_<n>" are no longer reserved, significant speedup.
  4378 
  4379 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4380 zChaff is still supported as well.
  4381 
  4382 * 'inductive' and 'datatype': provide projections of mutual rules,
  4383 bundled as foo_bar.inducts;
  4384 
  4385 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4386 Library.
  4387 
  4388 * Library: moved theory Accessible_Part to main HOL.
  4389 
  4390 * Library: added theory Coinductive_List of potentially infinite lists
  4391 as greatest fixed-point.
  4392 
  4393 * Library: added theory AssocList which implements (finite) maps as
  4394 association lists.
  4395 
  4396 * Method "evaluation" solves goals (i.e. a boolean expression)
  4397 efficiently by compiling it to ML.  The goal is "proved" (via an
  4398 oracle) if it evaluates to True.
  4399 
  4400 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4401 also when invoked by the simplifier.  This results in the Simplifier
  4402 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4403 Configuration option fast_arith_split_limit=0 recovers the old
  4404 behavior.
  4405 
  4406 * Support for hex (0x20) and binary (0b1001) numerals.
  4407 
  4408 * New method: reify eqs (t), where eqs are equations for an
  4409 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4410 parameter, computes a term s::'b and a list xs::'a list and proves the
  4411 theorem I xs s = t. This is also known as reification or quoting. The
  4412 resulting theorem is applied to the subgoal to substitute t with I xs
  4413 s.  If t is omitted, the subgoal itself is reified.
  4414 
  4415 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4416 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4417 where f is supposed to be a computable function (in the sense of code
  4418 generattion). The method uses reify to compute s and xs as above then
  4419 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4420 r and finally gets the theorem t = r, which is again applied to the
  4421 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4422 
  4423 * Reflection: Automatic reification now handels binding, an example is
  4424 available in src/HOL/ex/ReflectionEx.thy
  4425 
  4426 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4427 command 'statespace' that is similar to 'record', but introduces an
  4428 abstract specification based on the locale infrastructure instead of
  4429 HOL types.  This leads to extra flexibility in composing state spaces,
  4430 in particular multiple inheritance and renaming of components.
  4431 
  4432 
  4433 *** HOL-Complex ***
  4434 
  4435 * Hyperreal: Functions root and sqrt are now defined on negative real
  4436 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4437 Nonnegativity side conditions have been removed from many lemmas, so
  4438 that more subgoals may now be solved by simplification; potential
  4439 INCOMPATIBILITY.
  4440 
  4441 * Real: new type classes formalize real normed vector spaces and
  4442 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4443 and norm :: 'a => real.
  4444 
  4445 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4446 reals into other types. The overloaded constant Reals :: 'a set is now
  4447 defined as range of_real; potential INCOMPATIBILITY.
  4448 
  4449 * Real: proper support for ML code generation, including 'quickcheck'.
  4450 Reals are implemented as arbitrary precision rationals.
  4451 
  4452 * Hyperreal: Several constants that previously worked only for the
  4453 reals have been generalized, so they now work over arbitrary vector
  4454 spaces. Type annotations may need to be added in some cases; potential
  4455 INCOMPATIBILITY.
  4456 
  4457   Infinitesimal  :: ('a::real_normed_vector) star set
  4458   HFinite        :: ('a::real_normed_vector) star set
  4459   HInfinite      :: ('a::real_normed_vector) star set
  4460   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4461   monad          :: ('a::real_normed_vector) star => 'a star set
  4462   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4463   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4464   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4465   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4466   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4467   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4468   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4469   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4470   sgn            :: 'a::real_normed_vector => 'a
  4471   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4472 
  4473 * Complex: Some complex-specific constants are now abbreviations for
  4474 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4475 hnorm.  Other constants have been entirely removed in favor of the
  4476 polymorphic versions (INCOMPATIBILITY):
  4477 
  4478   approx        <-- capprox
  4479   HFinite       <-- CFinite
  4480   HInfinite     <-- CInfinite
  4481   Infinitesimal <-- CInfinitesimal
  4482   monad         <-- cmonad
  4483   galaxy        <-- cgalaxy
  4484   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4485   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4486   (ns)deriv     <-- (ns)cderiv
  4487 
  4488 
  4489 *** HOL-Algebra ***
  4490 
  4491 * Formalisation of ideals and the quotient construction over rings.
  4492 
  4493 * Order and lattice theory no longer based on records.
  4494 INCOMPATIBILITY.
  4495 
  4496 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4497 greatest_closed.  INCOMPATIBILITY.
  4498 
  4499 * Method algebra is now set up via an attribute.  For examples see
  4500 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4501 of algebraic structures.
  4502 
  4503 * Renamed theory CRing to Ring.
  4504 
  4505 
  4506 *** HOL-Nominal ***
  4507 
  4508 * Substantial, yet incomplete support for nominal datatypes (binding
  4509 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4510 src/HOL/Nominal/Examples.  Prospective users should consult
  4511 http://isabelle.in.tum.de/nominal/
  4512 
  4513 
  4514 *** ML ***
  4515 
  4516 * ML basics: just one true type int, which coincides with IntInf.int
  4517 (even on SML/NJ).
  4518 
  4519 * ML within Isar: antiquotations allow to embed statically-checked
  4520 formal entities in the source, referring to the context available at
  4521 compile-time.  For example:
  4522 
  4523 ML {* @{sort "{zero,one}"} *}
  4524 ML {* @{typ "'a => 'b"} *}
  4525 ML {* @{term "%x. x"} *}
  4526 ML {* @{prop "x == y"} *}
  4527 ML {* @{ctyp "'a => 'b"} *}
  4528 ML {* @{cterm "%x. x"} *}
  4529 ML {* @{cprop "x == y"} *}
  4530 ML {* @{thm asm_rl} *}
  4531 ML {* @{thms asm_rl} *}
  4532 ML {* @{type_name c} *}
  4533 ML {* @{type_syntax c} *}
  4534 ML {* @{const_name c} *}
  4535 ML {* @{const_syntax c} *}
  4536 ML {* @{context} *}
  4537 ML {* @{theory} *}
  4538 ML {* @{theory Pure} *}
  4539 ML {* @{theory_ref} *}
  4540 ML {* @{theory_ref Pure} *}
  4541 ML {* @{simpset} *}
  4542 ML {* @{claset} *}
  4543 ML {* @{clasimpset} *}
  4544 
  4545 The same works for sources being ``used'' within an Isar context.
  4546 
  4547 * ML in Isar: improved error reporting; extra verbosity with
  4548 ML_Context.trace enabled.
  4549 
  4550 * Pure/General/table.ML: the join operations now works via exceptions
  4551 DUP/SAME instead of type option. This is simpler in simple cases, and
  4552 admits slightly more efficient complex applications.
  4553 
  4554 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4555 use Context.generic instead of just theory.
  4556 
  4557 * Pure: datatype Context.generic joins theory/Proof.context and
  4558 provides some facilities for code that works in either kind of
  4559 context, notably GenericDataFun for uniform theory and proof data.
  4560 
  4561 * Pure: simplified internal attribute type, which is now always
  4562 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4563 local (Proof.context) attributes have been discontinued, while
  4564 minimizing code duplication. Thm.rule_attribute and
  4565 Thm.declaration_attribute build canonical attributes; see also structure
  4566 Context for further operations on Context.generic, notably
  4567 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4568 declarations and definitions.
  4569 
  4570 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4571 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4572 init only required for impure data. INCOMPATIBILITY: empty really need
  4573 to be empty (no dependencies on theory content!)
  4574 
  4575 * Pure/kernel: consts certification ignores sort constraints given in
  4576 signature declarations. (This information is not relevant to the
  4577 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4578 potential INCOMPATIBILITY.
  4579 
  4580 * Pure: axiomatic type classes are now purely definitional, with
  4581 explicit proofs of class axioms and super class relations performed
  4582 internally. See Pure/axclass.ML for the main internal interfaces --
  4583 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4584 AxClass.axiomatize_class/classrel/arity supersede
  4585 Sign.add_classes/classrel/arities.
  4586 
  4587 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4588 global/local versions on theory vs. Proof.context have been
  4589 discontinued; Attrib.syntax and Method.syntax have been adapted
  4590 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4591 attributes, methods, etc.
  4592 
  4593 * Pure: several functions of signature "... -> theory -> theory * ..."
  4594 have been reoriented to "... -> theory -> ... * theory" in order to
  4595 allow natural usage in combination with the ||>, ||>>, |-> and
  4596 fold_map combinators.
  4597 
  4598 * Pure: official theorem names (closed derivations) and additional
  4599 comments (tags) are now strictly separate.  Name hints -- which are
  4600 maintained as tags -- may be attached any time without affecting the
  4601 derivation.
  4602 
  4603 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4604 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4605 achieve the old behaviour.
  4606 
  4607 * Pure: the "Goal" constant is now called "prop", supporting a
  4608 slightly more general idea of ``protecting'' meta-level rule
  4609 statements.
  4610 
  4611 * Pure: Logic.(un)varify only works in a global context, which is now
  4612 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4613 Logic.legacy_(un)varify as temporary workaround.
  4614 
  4615 * Pure: structure Name provides scalable operations for generating
  4616 internal variable names, notably Name.variants etc.  This replaces
  4617 some popular functions from term.ML:
  4618 
  4619   Term.variant		->  Name.variant
  4620   Term.variantlist	->  Name.variant_list
  4621   Term.invent_names	->  Name.invent_list
  4622 
  4623 Note that low-level renaming rarely occurs in new code -- operations
  4624 from structure Variable are used instead (see below).
  4625 
  4626 * Pure: structure Variable provides fundamental operations for proper
  4627 treatment of fixed/schematic variables in a context.  For example,
  4628 Variable.import introduces fixes for schematics of given facts and
  4629 Variable.export reverses the effect (up to renaming) -- this replaces
  4630 various freeze_thaw operations.
  4631 
  4632 * Pure: structure Goal provides simple interfaces for
  4633 init/conclude/finish and tactical prove operations (replacing former
  4634 Tactic.prove).  Goal.prove is the canonical way to prove results
  4635 within a given context; Goal.prove_global is a degraded version for
  4636 theory level goals, including a global Drule.standard.  Note that
  4637 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4638 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4639 in a locale context).
  4640 
  4641 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4642 and type checking (Syntax.check_term etc.), with common combinations
  4643 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4644 which are considered legacy and await removal.
  4645 
  4646 * Pure/Syntax: generic interfaces for type unchecking
  4647 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4648 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4649 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4650 available for convenience, but refer to the very same operations using
  4651 a mere theory instead of a full context.
  4652 
  4653 * Isar: simplified treatment of user-level errors, using exception
  4654 ERROR of string uniformly.  Function error now merely raises ERROR,
  4655 without any side effect on output channels.  The Isar toplevel takes
  4656 care of proper display of ERROR exceptions.  ML code may use plain
  4657 handle/can/try; cat_error may be used to concatenate errors like this:
  4658 
  4659   ... handle ERROR msg => cat_error msg "..."
  4660 
  4661 Toplevel ML code (run directly or through the Isar toplevel) may be
  4662 embedded into the Isar toplevel with exception display/debug like
  4663 this:
  4664 
  4665   Isar.toplevel (fn () => ...)
  4666 
  4667 INCOMPATIBILITY, removed special transform_error facilities, removed
  4668 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4669 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4670 -- use plain ERROR instead.
  4671 
  4672 * Isar: theory setup now has type (theory -> theory), instead of a
  4673 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4674 
  4675 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4676 ProofContext.debug/verbose flags.
  4677 
  4678 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4679 theory before entering a proof state.  Transactions now always see a
  4680 quasi-functional intermediate checkpoint, both in interactive and
  4681 batch mode.
  4682 
  4683 * Isar: simplified interfaces for outer syntax.  Renamed
  4684 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4685 OuterSyntax.add_parsers -- this functionality is now included in
  4686 OuterSyntax.command etc.  INCOMPATIBILITY.
  4687 
  4688 * Simplifier: the simpset of a running simplification process now
  4689 contains a proof context (cf. Simplifier.the_context), which is the
  4690 very context that the initial simpset has been retrieved from (by
  4691 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4692 (solver, looper etc.) may depend on arbitrary proof data.
  4693 
  4694 * Simplifier.inherit_context inherits the proof context (plus the
  4695 local bounds) of the current simplification process; any simproc
  4696 etc. that calls the Simplifier recursively should do this!  Removed
  4697 former Simplifier.inherit_bounds, which is already included here --
  4698 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4699 specify an explicit context using Simplifier.context/theory_context.
  4700 
  4701 * Simplifier/Classical Reasoner: more abstract interfaces
  4702 change_simpset/claset for modifying the simpset/claset reference of a
  4703 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4704 INCOMPATIBILITY.
  4705 
  4706 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4707 "Trueprop" etc.
  4708 
  4709 
  4710 *** System ***
  4711 
  4712 * settings: the default heap location within ISABELLE_HOME_USER now
  4713 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4714 Isabelle installations.
  4715 
  4716 * isabelle-process: option -S (secure mode) disables some critical
  4717 operations, notably runtime compilation and evaluation of ML source
  4718 code.
  4719 
  4720 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4721 
  4722 * Support for parallel execution, using native multicore support of
  4723 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4724 independent theories, according to the given theory header
  4725 specifications. The maximum number of worker threads is specified via
  4726 usedir option -M or the "max-threads" setting in Proof General. A
  4727 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4728 to 6 on a 8-core machine.  User-code needs to observe certain
  4729 guidelines for thread-safe programming, see appendix A in the Isar
  4730 Implementation manual.
  4731 
  4732 
  4733 
  4734 New in Isabelle2005 (October 2005)
  4735 ----------------------------------
  4736 
  4737 *** General ***
  4738 
  4739 * Theory headers: the new header syntax for Isar theories is
  4740 
  4741   theory <name>
  4742   imports <theory1> ... <theoryN>
  4743   uses <file1> ... <fileM>
  4744   begin
  4745 
  4746 where the 'uses' part is optional.  The previous syntax
  4747 
  4748   theory <name> = <theory1> + ... + <theoryN>:
  4749 
  4750 will disappear in the next release.  Use isatool fixheaders to convert
  4751 existing theory files.  Note that there is no change in ancient
  4752 non-Isar theories now, but these will disappear soon.
  4753 
  4754 * Theory loader: parent theories can now also be referred to via
  4755 relative and absolute paths.
  4756 
  4757 * Command 'find_theorems' searches for a list of criteria instead of a
  4758 list of constants. Known criteria are: intro, elim, dest, name:string,
  4759 simp:term, and any term. Criteria can be preceded by '-' to select
  4760 theorems that do not match. Intro, elim, dest select theorems that
  4761 match the current goal, name:s selects theorems whose fully qualified
  4762 name contain s, and simp:term selects all simplification rules whose
  4763 lhs match term.  Any other term is interpreted as pattern and selects
  4764 all theorems matching the pattern. Available in ProofGeneral under
  4765 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4766 
  4767   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4768 
  4769 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4770 matching the current goal as introduction rule and not having "HOL."
  4771 in their name (i.e. not being defined in theory HOL).
  4772 
  4773 * Command 'thms_containing' has been discontinued in favour of
  4774 'find_theorems'; INCOMPATIBILITY.
  4775 
  4776 * Communication with Proof General is now 8bit clean, which means that
  4777 Unicode text in UTF-8 encoding may be used within theory texts (both
  4778 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4779 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4780 
  4781   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4782   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4783 
  4784 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4785 Classical Reasoner.  Typical big applications run around 2 times
  4786 faster.
  4787 
  4788 
  4789 *** Document preparation ***
  4790 
  4791 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4792 of raw sources.  Only those symbols that do not require additional
  4793 LaTeX packages (depending on comments in isabellesym.sty) are
  4794 displayed properly, everything else is left verbatim.  isatool display
  4795 and isatool print are used as front ends (these are subject to the
  4796 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4797 
  4798 * Command tags control specific markup of certain regions of text,
  4799 notably folding and hiding.  Predefined tags include "theory" (for
  4800 theory begin and end), "proof" for proof commands, and "ML" for
  4801 commands involving ML code; the additional tags "visible" and
  4802 "invisible" are unused by default.  Users may give explicit tag
  4803 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4804 interpretation of tags is determined by the LaTeX job during document
  4805 preparation: see option -V of isatool usedir, or options -n and -t of
  4806 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4807 \isadroptag.
  4808 
  4809 Several document versions may be produced at the same time via isatool
  4810 usedir (the generated index.html will link all of them).  Typical
  4811 specifications include ''-V document=theory,proof,ML'' to present
  4812 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4813 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4814 these parts without any formal replacement text.  The Isabelle site
  4815 default settings produce ''document'' and ''outline'' versions as
  4816 specified above.
  4817 
  4818 * Several new antiquotations:
  4819 
  4820   @{term_type term} prints a term with its type annotated;
  4821 
  4822   @{typeof term} prints the type of a term;
  4823 
  4824   @{const const} is the same as @{term const}, but checks that the
  4825   argument is a known logical constant;
  4826 
  4827   @{term_style style term} and @{thm_style style thm} print a term or
  4828   theorem applying a "style" to it
  4829 
  4830   @{ML text}
  4831 
  4832 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4833 definitions, equations, inequations etc., 'concl' printing only the
  4834 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4835 to print the specified premise.  TermStyle.add_style provides an ML
  4836 interface for introducing further styles.  See also the "LaTeX Sugar"
  4837 document practical applications.  The ML antiquotation prints
  4838 type-checked ML expressions verbatim.
  4839 
  4840 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4841 and 'text' support optional locale specification '(in loc)', which
  4842 specifies the default context for interpreting antiquotations.  For
  4843 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4844 
  4845 * Option 'locale=NAME' of antiquotations specifies an alternative
  4846 context interpreting the subsequent argument.  For example: @{thm
  4847 [locale=lattice] inf_assoc}.
  4848 
  4849 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4850 a proof context.
  4851 
  4852 * Proper output of antiquotations for theory commands involving a
  4853 proof context (such as 'locale' or 'theorem (in loc) ...').
  4854 
  4855 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4856 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4857 
  4858 * isatool usedir: new option -C (default true) controls whether option
  4859 -D should include a copy of the original document directory; -C false
  4860 prevents unwanted effects such as copying of administrative CVS data.
  4861 
  4862 
  4863 *** Pure ***
  4864 
  4865 * Considerably improved version of 'constdefs' command.  Now performs
  4866 automatic type-inference of declared constants; additional support for
  4867 local structure declarations (cf. locales and HOL records), see also
  4868 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4869 sequential dependencies of definitions within a single 'constdefs'
  4870 section; moreover, the declared name needs to be an identifier.  If
  4871 all fails, consider to fall back on 'consts' and 'defs' separately.
  4872 
  4873 * Improved indexed syntax and implicit structures.  First of all,
  4874 indexed syntax provides a notational device for subscripted
  4875 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4876 expressions.  Secondly, in a local context with structure
  4877 declarations, number indexes \<^sub>n or the empty index (default
  4878 number 1) refer to a certain fixed variable implicitly; option
  4879 show_structs controls printing of implicit structures.  Typical
  4880 applications of these concepts involve record types and locales.
  4881 
  4882 * New command 'no_syntax' removes grammar declarations (and
  4883 translations) resulting from the given syntax specification, which is
  4884 interpreted in the same manner as for the 'syntax' command.
  4885 
  4886 * 'Advanced' translation functions (parse_translation etc.) may depend
  4887 on the signature of the theory context being presently used for
  4888 parsing/printing, see also isar-ref manual.
  4889 
  4890 * Improved 'oracle' command provides a type-safe interface to turn an
  4891 ML expression of type theory -> T -> term into a primitive rule of
  4892 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4893 is already included here); see also FOL/ex/IffExample.thy;
  4894 INCOMPATIBILITY.
  4895 
  4896 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4897 before); "cI" is no longer bound, use "c.intro" instead.
  4898 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4899 axclasses vs. locales.
  4900 
  4901 * Improved internal renaming of symbolic identifiers -- attach primes
  4902 instead of base 26 numbers.
  4903 
  4904 * New flag show_question_marks controls printing of leading question
  4905 marks in schematic variable names.
  4906 
  4907 * In schematic variable names, *any* symbol following \<^isub> or
  4908 \<^isup> is now treated as part of the base name.  For example, the
  4909 following works without printing of awkward ".0" indexes:
  4910 
  4911   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4912     by simp
  4913 
  4914 * Inner syntax includes (*(*nested*) comments*).
  4915 
  4916 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4917 annotations as "(00...)".
  4918 
  4919 * Clear separation of logical types and nonterminals, where the latter
  4920 may only occur in 'syntax' specifications or type abbreviations.
  4921 Before that distinction was only partially implemented via type class
  4922 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4923 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4924 exotic syntax specifications may require further adaption
  4925 (e.g. Cube/Cube.thy).
  4926 
  4927 * Removed obsolete type class "logic", use the top sort {} instead.
  4928 Note that non-logical types should be declared as 'nonterminals'
  4929 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4930 specifications.
  4931 
  4932 * Attributes 'induct' and 'cases': type or set names may now be
  4933 locally fixed variables as well.
  4934 
  4935 * Simplifier: can now control the depth to which conditional rewriting
  4936 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4937 Limit.
  4938 
  4939 * Simplifier: simplification procedures may now take the current
  4940 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4941 interface), which is very useful for calling the Simplifier
  4942 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4943 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4944 low-level mk_simproc no longer applies Logic.varify internally, to
  4945 allow for use in a context of fixed variables.
  4946 
  4947 * thin_tac now works even if the assumption being deleted contains !!
  4948 or ==>.  More generally, erule now works even if the major premise of
  4949 the elimination rule contains !! or ==>.
  4950 
  4951 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4952 
  4953 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4954 from Pure, which contains all common declarations already.  Both
  4955 theories are defined via plain Isabelle/Isar .thy files.
  4956 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4957 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4958 use isatool fixcpure to adapt your theory and ML sources.
  4959 
  4960 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4961 selections of theorems in named facts via index ranges.
  4962 
  4963 * 'print_theorems': in theory mode, really print the difference
  4964 wrt. the last state (works for interactive theory development only),
  4965 in proof mode print all local facts (cf. 'print_facts');
  4966 
  4967 * 'hide': option '(open)' hides only base names.
  4968 
  4969 * More efficient treatment of intermediate checkpoints in interactive
  4970 theory development.
  4971 
  4972 * Code generator is now invoked via code_module (incremental code
  4973 generation) and code_library (modular code generation, ML structures
  4974 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4975 must be quoted when used as identifiers.
  4976 
  4977 * New 'value' command for reading, evaluating and printing terms using
  4978 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4979 quoted when used as identifier.
  4980 
  4981 
  4982 *** Locales ***
  4983 
  4984 * New commands for the interpretation of locale expressions in
  4985 theories (1), locales (2) and proof contexts (3).  These generate
  4986 proof obligations from the expression specification.  After the
  4987 obligations have been discharged, theorems of the expression are added
  4988 to the theory, target locale or proof context.  The synopsis of the
  4989 commands is a follows:
  4990 
  4991   (1) interpretation expr inst
  4992   (2) interpretation target < expr
  4993   (3) interpret expr inst
  4994 
  4995 Interpretation in theories and proof contexts require a parameter
  4996 instantiation of terms from the current context.  This is applied to
  4997 specifications and theorems of the interpreted expression.
  4998 Interpretation in locales only permits parameter renaming through the
  4999 locale expression.  Interpretation is smart in that interpretations
  5000 that are active already do not occur in proof obligations, neither are
  5001 instantiated theorems stored in duplicate.  Use 'print_interps' to
  5002 inspect active interpretations of a particular locale.  For details,
  5003 see the Isar Reference manual.  Examples can be found in
  5004 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  5005 
  5006 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  5007 'interpret' instead.
  5008 
  5009 * New context element 'constrains' for adding type constraints to
  5010 parameters.
  5011 
  5012 * Context expressions: renaming of parameters with syntax
  5013 redeclaration.
  5014 
  5015 * Locale declaration: 'includes' disallowed.
  5016 
  5017 * Proper static binding of attribute syntax -- i.e. types / terms /
  5018 facts mentioned as arguments are always those of the locale definition
  5019 context, independently of the context of later invocations.  Moreover,
  5020 locale operations (renaming and type / term instantiation) are applied
  5021 to attribute arguments as expected.
  5022 
  5023 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  5024 actual attributes; rare situations may require Attrib.attribute to
  5025 embed those attributes into Attrib.src that lack concrete syntax.
  5026 Attribute implementations need to cooperate properly with the static
  5027 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  5028 Attrib.XXX_thm etc. already do the right thing without further
  5029 intervention.  Only unusual applications -- such as "where" or "of"
  5030 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  5031 on the context and the facts involved -- may have to assign parsed
  5032 values to argument tokens explicitly.
  5033 
  5034 * Changed parameter management in theorem generation for long goal
  5035 statements with 'includes'.  INCOMPATIBILITY: produces a different
  5036 theorem statement in rare situations.
  5037 
  5038 * Locale inspection command 'print_locale' omits notes elements.  Use
  5039 'print_locale!' to have them included in the output.
  5040 
  5041 
  5042 *** Provers ***
  5043 
  5044 * Provers/hypsubst.ML: improved version of the subst method, for
  5045 single-step rewriting: it now works in bound variable contexts. New is
  5046 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  5047 rewrite a different subterm than the original subst method, which is
  5048 still available as 'simplesubst'.
  5049 
  5050 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  5051 and quasi orders.
  5052 
  5053 * Provers/trancl.ML: new transitivity reasoner for transitive and
  5054 reflexive-transitive closure of relations.
  5055 
  5056 * Provers/blast.ML: new reference depth_limit to make blast's depth
  5057 limit (previously hard-coded with a value of 20) user-definable.
  5058 
  5059 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  5060 is peformed already.  Object-logics merely need to finish their
  5061 initial simpset configuration as before.  INCOMPATIBILITY.
  5062 
  5063 
  5064 *** HOL ***
  5065 
  5066 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  5067 
  5068   syntax (epsilon)
  5069     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  5070 
  5071 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  5072 and x-symbol; use option '-m epsilon' to get it actually printed.
  5073 Moreover, the mathematically important symbolic identifier \<epsilon>
  5074 becomes available as variable, constant etc.  INCOMPATIBILITY,
  5075 
  5076 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  5077 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  5078 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  5079 support corresponding Isar calculations.
  5080 
  5081 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  5082 instead of ":".
  5083 
  5084 * theory SetInterval: changed the syntax for open intervals:
  5085 
  5086   Old       New
  5087   {..n(}    {..<n}
  5088   {)n..}    {n<..}
  5089   {m..n(}   {m..<n}
  5090   {)m..n}   {m<..n}
  5091   {)m..n(}  {m<..<n}
  5092 
  5093 The old syntax is still supported but will disappear in the next
  5094 release.  For conversion use the following Emacs search and replace
  5095 patterns (these are not perfect but work quite well):
  5096 
  5097   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  5098   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  5099 
  5100 * Theory Commutative_Ring (in Library): method comm_ring for proving
  5101 equalities in commutative rings; method 'algebra' provides a generic
  5102 interface.
  5103 
  5104 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  5105 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  5106 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  5107 be a tuple pattern.
  5108 
  5109 Some new syntax forms are available:
  5110 
  5111   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  5112   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  5113   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  5114   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  5115 
  5116 The latter form "\<Sum>x < k. e" used to be based on a separate
  5117 function "Summation", which has been discontinued.
  5118 
  5119 * theory Finite_Set: in structured induction proofs, the insert case
  5120 is now 'case (insert x F)' instead of the old counterintuitive 'case
  5121 (insert F x)'.
  5122 
  5123 * The 'refute' command has been extended to support a much larger
  5124 fragment of HOL, including axiomatic type classes, constdefs and
  5125 typedefs, inductive datatypes and recursion.
  5126 
  5127 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  5128 Requires zChaff with proof generation to be installed.  See
  5129 HOL/ex/SAT_Examples.thy for examples.
  5130 
  5131 * Datatype induction via method 'induct' now preserves the name of the
  5132 induction variable. For example, when proving P(xs::'a list) by
  5133 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  5134 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  5135 in unstructured proof scripts.
  5136 
  5137 * Reworked implementation of records.  Improved scalability for
  5138 records with many fields, avoiding performance problems for type
  5139 inference. Records are no longer composed of nested field types, but
  5140 of nested extension types. Therefore the record type only grows linear
  5141 in the number of extensions and not in the number of fields.  The
  5142 top-level (users) view on records is preserved.  Potential
  5143 INCOMPATIBILITY only in strange cases, where the theory depends on the
  5144 old record representation. The type generated for a record is called
  5145 <record_name>_ext_type.
  5146 
  5147 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  5148 proofs triggered by a record definition or a simproc (if
  5149 quick_and_dirty is enabled).  Definitions of large records can take
  5150 quite long.
  5151 
  5152 New simproc record_upd_simproc for simplification of multiple record
  5153 updates enabled by default.  Moreover, trivial updates are also
  5154 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  5155 occasionally, since simplification is more powerful by default.
  5156 
  5157 * typedef: proper support for polymorphic sets, which contain extra
  5158 type-variables in the term.
  5159 
  5160 * Simplifier: automatically reasons about transitivity chains
  5161 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  5162 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  5163 old proofs break occasionally as simplification may now solve more
  5164 goals than previously.
  5165 
  5166 * Simplifier: converts x <= y into x = y if assumption y <= x is
  5167 present.  Works for all partial orders (class "order"), in particular
  5168 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  5169 just like y <= x.
  5170 
  5171 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  5172 bound variable or a constant then the let is unfolded.  Otherwise
  5173 first a is simplified to b, and then f b is simplified to g. If
  5174 possible we abstract b from g arriving at "let x = b in h x",
  5175 otherwise we unfold the let and arrive at g.  The simproc can be
  5176 enabled/disabled by the reference use_let_simproc.  Potential
  5177 INCOMPATIBILITY since simplification is more powerful by default.
  5178 
  5179 * Classical reasoning: the meson method now accepts theorems as arguments.
  5180 
  5181 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  5182 jobs to provide advice on the provability of subgoals.
  5183 
  5184 * Theory OrderedGroup and Ring_and_Field: various additions and
  5185 improvements to faciliate calculations involving equalities and
  5186 inequalities.
  5187 
  5188 The following theorems have been eliminated or modified
  5189 (INCOMPATIBILITY):
  5190 
  5191   abs_eq             now named abs_of_nonneg
  5192   abs_of_ge_0        now named abs_of_nonneg
  5193   abs_minus_eq       now named abs_of_nonpos
  5194   imp_abs_id         now named abs_of_nonneg
  5195   imp_abs_neg_id     now named abs_of_nonpos
  5196   mult_pos           now named mult_pos_pos
  5197   mult_pos_le        now named mult_nonneg_nonneg
  5198   mult_pos_neg_le    now named mult_nonneg_nonpos
  5199   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5200   mult_neg           now named mult_neg_neg
  5201   mult_neg_le        now named mult_nonpos_nonpos
  5202 
  5203 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5204      
  5205      zero_le_square
  5206      not_square_less_zero 
  5207 
  5208   The following lemmas have been deleted from Real/RealPow:
  5209   
  5210      realpow_zero_zero
  5211      realpow_two
  5212      realpow_less
  5213      zero_le_power
  5214      realpow_two_le
  5215      abs_realpow_two
  5216      realpow_two_abs     
  5217 
  5218 * Theory Parity: added rules for simplifying exponents.
  5219 
  5220 * Theory List:
  5221 
  5222 The following theorems have been eliminated or modified
  5223 (INCOMPATIBILITY):
  5224 
  5225   list_all_Nil       now named list_all.simps(1)
  5226   list_all_Cons      now named list_all.simps(2)
  5227   list_all_conv      now named list_all_iff
  5228   set_mem_eq         now named mem_iff
  5229 
  5230 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5231 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5232 
  5233 
  5234 *** HOL-Complex ***
  5235 
  5236 * Theory RealDef: better support for embedding natural numbers and
  5237 integers in the reals.
  5238 
  5239 The following theorems have been eliminated or modified
  5240 (INCOMPATIBILITY):
  5241 
  5242   exp_ge_add_one_self  now requires no hypotheses
  5243   real_of_int_add      reversed direction of equality (use [symmetric])
  5244   real_of_int_minus    reversed direction of equality (use [symmetric])
  5245   real_of_int_diff     reversed direction of equality (use [symmetric])
  5246   real_of_int_mult     reversed direction of equality (use [symmetric])
  5247 
  5248 * Theory RComplete: expanded support for floor and ceiling functions.
  5249 
  5250 * Theory Ln is new, with properties of the natural logarithm
  5251 
  5252 * Hyperreal: There is a new type constructor "star" for making
  5253 nonstandard types.  The old type names are now type synonyms:
  5254 
  5255   hypreal = real star
  5256   hypnat = nat star
  5257   hcomplex = complex star
  5258 
  5259 * Hyperreal: Many groups of similarly-defined constants have been
  5260 replaced by polymorphic versions (INCOMPATIBILITY):
  5261 
  5262   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5263 
  5264   starset      <-- starsetNat, starsetC
  5265   *s*          <-- *sNat*, *sc*
  5266   starset_n    <-- starsetNat_n, starsetC_n
  5267   *sn*         <-- *sNatn*, *scn*
  5268   InternalSets <-- InternalNatSets, InternalCSets
  5269 
  5270   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5271   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5272   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5273   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5274   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5275 
  5276 * Hyperreal: Many type-specific theorems have been removed in favor of
  5277 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5278 
  5279   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5280   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5281   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5282   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5283   right_minus <-- hypreal_add_minus
  5284   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5285   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5286   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5287   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5288   mult_1_right <-- hcomplex_mult_one_right
  5289   mult_zero_left <-- hcomplex_mult_zero_left
  5290   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5291   right_distrib <-- hypnat_add_mult_distrib2
  5292   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5293   right_inverse <-- hypreal_mult_inverse
  5294   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5295   order_refl <-- {hypreal,hypnat}_le_refl
  5296   order_trans <-- {hypreal,hypnat}_le_trans
  5297   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5298   order_less_le <-- {hypreal,hypnat}_less_le
  5299   linorder_linear <-- {hypreal,hypnat}_le_linear
  5300   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5301   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5302   add_nonneg_nonneg <-- hypreal_le_add_order
  5303 
  5304 * Hyperreal: Separate theorems having to do with type-specific
  5305 versions of constants have been merged into theorems that apply to the
  5306 new polymorphic constants (INCOMPATIBILITY):
  5307 
  5308   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5309   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5310   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5311   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5312   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5313   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5314   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5315   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5316   STAR_diff <-- {STAR,STARC}_diff
  5317   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5318     STARC_hcomplex_of_complex}_image_subset
  5319   starset_n_Un <-- starset{Nat,C}_n_Un
  5320   starset_n_Int <-- starset{Nat,C}_n_Int
  5321   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5322   starset_n_diff <-- starset{Nat,C}_n_diff
  5323   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5324   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5325   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5326   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5327   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5328   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5329   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5330   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5331   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5332   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5333   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5334   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5335   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5336   starfun_diff <-- starfun{C,RC,CR}_diff
  5337   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5338   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5339   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5340   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5341   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5342   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5343   starfun_Id <-- starfunC_Id
  5344   starfun_approx <-- starfun{Nat,CR}_approx
  5345   starfun_capprox <-- starfun{C,RC}_capprox
  5346   starfun_abs <-- starfunNat_rabs
  5347   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5348   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5349   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5350   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5351   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5352   starfun_add_approx <-- starfunCR_add_approx
  5353   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5354   starfun_divide <-- starfun{C,CR,RC}_divide
  5355   starfun_n <-- starfun{Nat,C}_n
  5356   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5357   starfun_n_add <-- starfun{Nat,C}_n_add
  5358   starfun_n_add_minus <-- starfunNat_n_add_minus
  5359   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5360   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5361   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5362 
  5363   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5364   star_n_minus <-- {hypreal,hcomplex}_minus
  5365   star_n_diff <-- {hypreal,hcomplex}_diff
  5366   star_n_mult <-- {hypreal,hcomplex}_mult
  5367   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5368   star_n_le <-- {hypreal,hypnat}_le
  5369   star_n_less <-- {hypreal,hypnat}_less
  5370   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5371   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5372   star_n_abs <-- hypreal_hrabs
  5373   star_n_divide <-- hcomplex_divide
  5374 
  5375   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5376   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5377   star_of_diff <-- hypreal_of_real_diff
  5378   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5379   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5380   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5381   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5382   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5383   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5384   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5385   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5386   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5387   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5388   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5389   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5390   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5391   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5392   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5393   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5394   star_of_power <-- hypreal_of_real_power
  5395   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5396 
  5397 * Hyperreal: new method "transfer" that implements the transfer
  5398 principle of nonstandard analysis. With a subgoal that mentions
  5399 nonstandard types like "'a star", the command "apply transfer"
  5400 replaces it with an equivalent one that mentions only standard types.
  5401 To be successful, all free variables must have standard types; non-
  5402 standard variables must have explicit universal quantifiers.
  5403 
  5404 * Hyperreal: A theory of Taylor series.
  5405 
  5406 
  5407 *** HOLCF ***
  5408 
  5409 * Discontinued special version of 'constdefs' (which used to support
  5410 continuous functions) in favor of the general Pure one with full
  5411 type-inference.
  5412 
  5413 * New simplification procedure for solving continuity conditions; it
  5414 is much faster on terms with many nested lambda abstractions (cubic
  5415 instead of exponential time).
  5416 
  5417 * New syntax for domain package: selector names are now optional.
  5418 Parentheses should be omitted unless argument is lazy, for example:
  5419 
  5420   domain 'a stream = cons "'a" (lazy "'a stream")
  5421 
  5422 * New command 'fixrec' for defining recursive functions with pattern
  5423 matching; defining multiple functions with mutual recursion is also
  5424 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5425 sinr, or any data constructor defined by the domain package. The given
  5426 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5427 syntax and examples.
  5428 
  5429 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5430 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5431 but the proof obligation additionally includes an admissibility
  5432 requirement. The packages generate instances of class cpo or pcpo,
  5433 with continuity and strictness theorems for Rep and Abs.
  5434 
  5435 * HOLCF: Many theorems have been renamed according to a more standard naming
  5436 scheme (INCOMPATIBILITY):
  5437 
  5438   foo_inject:  "foo$x = foo$y ==> x = y"
  5439   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5440   foo_less:    "(foo$x << foo$y) = (x << y)"
  5441   foo_strict:  "foo$UU = UU"
  5442   foo_defined: "... ==> foo$x ~= UU"
  5443   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5444 
  5445 
  5446 *** ZF ***
  5447 
  5448 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5449 including the First Isomorphism Theorem (on quotienting by the kernel
  5450 of a homomorphism).
  5451 
  5452 * ZF/Simplifier: install second copy of type solver that actually
  5453 makes use of TC rules declared to Isar proof contexts (or locales);
  5454 the old version is still required for ML proof scripts.
  5455 
  5456 
  5457 *** Cube ***
  5458 
  5459 * Converted to Isar theory format; use locales instead of axiomatic
  5460 theories.
  5461 
  5462 
  5463 *** ML ***
  5464 
  5465 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5466 for ||>, ||>>, |>>,
  5467 
  5468 * Pure/library.ML no longer defines its own option datatype, but uses
  5469 that of the SML basis, which has constructors NONE and SOME instead of
  5470 None and Some, as well as exception Option.Option instead of OPTION.
  5471 The functions the, if_none, is_some, is_none have been adapted
  5472 accordingly, while Option.map replaces apsome.
  5473 
  5474 * Pure/library.ML: the exception LIST has been given up in favour of
  5475 the standard exceptions Empty and Subscript, as well as
  5476 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5477 superceded by the standard hd and tl functions etc.
  5478 
  5479 A number of basic list functions are no longer exported to the ML
  5480 toplevel, as they are variants of predefined functions.  The following
  5481 suggests how one can translate existing code:
  5482 
  5483     rev_append xs ys = List.revAppend (xs, ys)
  5484     nth_elem (i, xs) = List.nth (xs, i)
  5485     last_elem xs = List.last xs
  5486     flat xss = List.concat xss
  5487     seq fs = List.app fs
  5488     partition P xs = List.partition P xs
  5489     mapfilter f xs = List.mapPartial f xs
  5490 
  5491 * Pure/library.ML: several combinators for linear functional
  5492 transformations, notably reverse application and composition:
  5493 
  5494   x |> f                f #> g
  5495   (x, y) |-> f          f #-> g
  5496 
  5497 * Pure/library.ML: introduced/changed precedence of infix operators:
  5498 
  5499   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5500   infix 2 ?;
  5501   infix 3 o oo ooo oooo;
  5502   infix 4 ~~ upto downto;
  5503 
  5504 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5505 infix operators.
  5506 
  5507 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5508 fold_map support linear functional transformations and nesting.  For
  5509 example:
  5510 
  5511   fold f [x1, ..., xN] y =
  5512     y |> f x1 |> ... |> f xN
  5513 
  5514   (fold o fold) f [xs1, ..., xsN] y =
  5515     y |> fold f xs1 |> ... |> fold f xsN
  5516 
  5517   fold f [x1, ..., xN] =
  5518     f x1 #> ... #> f xN
  5519 
  5520   (fold o fold) f [xs1, ..., xsN] =
  5521     fold f xs1 #> ... #> fold f xsN
  5522 
  5523 * Pure/library.ML: the following selectors on type 'a option are
  5524 available:
  5525 
  5526   the:               'a option -> 'a  (*partial*)
  5527   these:             'a option -> 'a  where 'a = 'b list
  5528   the_default: 'a -> 'a option -> 'a
  5529   the_list:          'a option -> 'a list
  5530 
  5531 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5532 basic operations for association lists, following natural argument
  5533 order; moreover the explicit equality predicate passed here avoids
  5534 potentially expensive polymorphic runtime equality checks.
  5535 The old functions may be expressed as follows:
  5536 
  5537   assoc = uncurry (AList.lookup (op =))
  5538   assocs = these oo AList.lookup (op =)
  5539   overwrite = uncurry (AList.update (op =)) o swap
  5540 
  5541 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5542 
  5543   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5544   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5545 
  5546 replacing make_keylist and keyfilter (occassionally used)
  5547 Naive rewrites:
  5548 
  5549   make_keylist = AList.make
  5550   keyfilter = AList.find (op =)
  5551 
  5552 * eq_fst and eq_snd now take explicit equality parameter, thus
  5553   avoiding eqtypes. Naive rewrites:
  5554 
  5555     eq_fst = eq_fst (op =)
  5556     eq_snd = eq_snd (op =)
  5557 
  5558 * Removed deprecated apl and apr (rarely used).
  5559   Naive rewrites:
  5560 
  5561     apl (n, op) =>>= curry op n
  5562     apr (op, m) =>>= fn n => op (n, m)
  5563 
  5564 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5565 provides a reasonably efficient light-weight implementation of sets as
  5566 lists.
  5567 
  5568 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5569 few new operations; existing lookup and update are now curried to
  5570 follow natural argument order (for use with fold etc.);
  5571 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5572 
  5573 * Pure/General: output via the Isabelle channels of
  5574 writeln/warning/error etc. is now passed through Output.output, with a
  5575 hook for arbitrary transformations depending on the print_mode
  5576 (cf. Output.add_mode -- the first active mode that provides a output
  5577 function wins).  Already formatted output may be embedded into further
  5578 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5579 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5580 accommodate easy composition of diagnostic messages etc.  Programmers
  5581 rarely need to care about Output.output or Output.raw at all, with
  5582 some notable exceptions: Output.output is required when bypassing the
  5583 standard channels (writeln etc.), or in token translations to produce
  5584 properly formatted results; Output.raw is required when capturing
  5585 already output material that will eventually be presented to the user
  5586 a second time.  For the default print mode, both Output.output and
  5587 Output.raw have no effect.
  5588 
  5589 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5590 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5591 cumulative results are displayed at the end of a batch session.
  5592 
  5593 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5594 replaced by File.platform_path and File.shell_path (with appropriate
  5595 hooks).  This provides a clean interface for unusual systems where the
  5596 internal and external process view of file names are different.
  5597 
  5598 * Pure: more efficient orders for basic syntactic entities: added
  5599 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5600 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5601 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5602 orders now -- potential INCOMPATIBILITY for code that depends on a
  5603 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5604 Library.sort_strings on result).
  5605 
  5606 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5607 fold_types traverse types/terms from left to right, observing natural
  5608 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5609 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5610 
  5611 * Pure: name spaces have been refined, with significant changes of the
  5612 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5613 to extern(_table).  The plain name entry path is superceded by a
  5614 general 'naming' context, which also includes the 'policy' to produce
  5615 a fully qualified name and external accesses of a fully qualified
  5616 name; NameSpace.extend is superceded by context dependent
  5617 Sign.declare_name.  Several theory and proof context operations modify
  5618 the naming context.  Especially note Theory.restore_naming and
  5619 ProofContext.restore_naming to get back to a sane state; note that
  5620 Theory.add_path is no longer sufficient to recover from
  5621 Theory.absolute_path in particular.
  5622 
  5623 * Pure: new flags short_names (default false) and unique_names
  5624 (default true) for controlling output of qualified names.  If
  5625 short_names is set, names are printed unqualified.  If unique_names is
  5626 reset, the name prefix is reduced to the minimum required to achieve
  5627 the original result when interning again, even if there is an overlap
  5628 with earlier declarations.
  5629 
  5630 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5631 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5632 (useful for printing error messages).  INCOMPATIBILITY.
  5633 
  5634 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5635 Theory.theory are now identified, referring to the universal
  5636 Context.theory (see Pure/context.ML).  Actual signature and theory
  5637 content is managed as theory data.  The old code and interfaces were
  5638 spread over many files and structures; the new arrangement introduces
  5639 considerable INCOMPATIBILITY to gain more clarity:
  5640 
  5641   Context -- theory management operations (name, identity, inclusion,
  5642     parents, ancestors, merge, etc.), plus generic theory data;
  5643 
  5644   Sign -- logical signature and syntax operations (declaring consts,
  5645     types, etc.), plus certify/read for common entities;
  5646 
  5647   Theory -- logical theory operations (stating axioms, definitions,
  5648     oracles), plus a copy of logical signature operations (consts,
  5649     types, etc.); also a few basic management operations (Theory.copy,
  5650     Theory.merge, etc.)
  5651 
  5652 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5653 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5654 for convenience -- they merely return the theory.
  5655 
  5656 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5657 
  5658 * Pure: the Isar proof context type is already defined early in Pure
  5659 as Context.proof (note that ProofContext.context and Proof.context are
  5660 aliases, where the latter is the preferred name).  This enables other
  5661 Isabelle components to refer to that type even before Isar is present.
  5662 
  5663 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5664 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5665 any of these kinds.  For example, Sign.intern typeK is now
  5666 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5667 Theory.hide_types.  Also note that former
  5668 Theory.hide_classes/types/consts are now
  5669 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5670 internalize their arguments!  INCOMPATIBILITY.
  5671 
  5672 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5673 datatype thmref (with constructors Name and NameSelection) instead of
  5674 plain string -- INCOMPATIBILITY;
  5675 
  5676 * Pure: cases produced by proof methods specify options, where NONE
  5677 means to remove case bindings -- INCOMPATIBILITY in
  5678 (RAW_)METHOD_CASES.
  5679 
  5680 * Pure: the following operations retrieve axioms or theorems from a
  5681 theory node or theory hierarchy, respectively:
  5682 
  5683   Theory.axioms_of: theory -> (string * term) list
  5684   Theory.all_axioms_of: theory -> (string * term) list
  5685   PureThy.thms_of: theory -> (string * thm) list
  5686   PureThy.all_thms_of: theory -> (string * thm) list
  5687 
  5688 * Pure: print_tac now outputs the goal through the trace channel.
  5689 
  5690 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5691 Reference Toplevel.debug (default false) controls detailed printing
  5692 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5693 controls execution profiling -- set to 1 for time and 2 for space
  5694 (both increase the runtime).
  5695 
  5696 * Isar session: The initial use of ROOT.ML is now always timed,
  5697 i.e. the log will show the actual process times, in contrast to the
  5698 elapsed wall-clock time that the outer shell wrapper produces.
  5699 
  5700 * Simplifier: improved handling of bound variables (nameless
  5701 representation, avoid allocating new strings).  Simprocs that invoke
  5702 the Simplifier recursively should use Simplifier.inherit_bounds to
  5703 avoid local name clashes.  Failure to do so produces warnings
  5704 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5705 for further details.
  5706 
  5707 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5708 bindings for all theorems stored within a given theory; this may help
  5709 in porting non-Isar theories to Isar ones, while keeping ML proof
  5710 scripts for the time being.
  5711 
  5712 * ML operator HTML.with_charset specifies the charset begin used for
  5713 generated HTML files.  For example:
  5714 
  5715   HTML.with_charset "utf-8" use_thy "Hebrew";
  5716   HTML.with_charset "utf-8" use_thy "Chinese";
  5717 
  5718 
  5719 *** System ***
  5720 
  5721 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5722 isabelle, isatool etc.).
  5723 
  5724 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5725 isatool doc, isatool mkdir, display_drafts etc.).
  5726 
  5727 * isatool usedir: option -f allows specification of the ML file to be
  5728 used by Isabelle; default is ROOT.ML.
  5729 
  5730 * New isatool version outputs the version identifier of the Isabelle
  5731 distribution being used.
  5732 
  5733 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5734 (containing Boolean satisfiability problems) into Isabelle/HOL
  5735 theories.
  5736 
  5737 
  5738 
  5739 New in Isabelle2004 (April 2004)
  5740 --------------------------------
  5741 
  5742 *** General ***
  5743 
  5744 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5745   Replaces linorder.ML.
  5746 
  5747 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5748   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5749   (\<a>...\<z>), are now considered normal letters, and can therefore
  5750   be used anywhere where an ASCII letter (a...zA...Z) has until
  5751   now. COMPATIBILITY: This obviously changes the parsing of some
  5752   terms, especially where a symbol has been used as a binder, say
  5753   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5754   as an identifier.  Fix it by inserting a space around former
  5755   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5756   existing theory and ML files.
  5757 
  5758 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5759 
  5760 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5761   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5762   a normal (but invisible) letter. For multiple letter subscripts repeat
  5763   \<^isub> like this: x\<^isub>1\<^isub>2.
  5764 
  5765 * Pure: There are now sub-/superscripts that can span more than one
  5766   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5767   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5768   superscript. The new control characters are not identifier parts.
  5769 
  5770 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5771   content of "..." to the latex file instead of \isacntrl... . The "..."
  5772   may consist of any printable characters excluding the end bracket >.
  5773 
  5774 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5775   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5776   declare constants "final", which prevents their being given a definition
  5777   later.  It is useful for constants whose behaviour is fixed axiomatically
  5778   rather than definitionally, such as the meta-logic connectives.
  5779 
  5780 * Pure: 'instance' now handles general arities with general sorts
  5781   (i.e. intersections of classes),
  5782 
  5783 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5784   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5785   It can be changed to alter the colors/layout of generated pages.
  5786 
  5787 
  5788 *** Isar ***
  5789 
  5790 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5791   cut_tac, subgoal_tac and thin_tac:
  5792   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5793     locales are no longer forced to write Isar proof scripts.
  5794     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5795     emulations.
  5796   - INCOMPATIBILITY: names of variables to be instantiated may no
  5797     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5798     This is consistent with the instantiation attribute "where".
  5799 
  5800 * Attributes "where" and "of":
  5801   - Now take type variables of instantiated theorem into account when reading
  5802     the instantiation string.  This fixes a bug that caused instantiated
  5803     theorems to have too special types in some circumstances.
  5804   - "where" permits explicit instantiations of type variables.
  5805 
  5806 * Calculation commands "moreover" and "also" no longer interfere with
  5807   current facts ("this"), admitting arbitrary combinations with "then"
  5808   and derived forms.
  5809 
  5810 * Locales:
  5811   - Goal statements involving the context element "includes" no longer
  5812     generate theorems with internal delta predicates (those ending on
  5813     "_axioms") in the premise.
  5814     Resolve particular premise with <locale>.intro to obtain old form.
  5815   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5816     specification and "includes" elements in goal statement.
  5817   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5818     [intro?] and [elim?] (respectively) by default.
  5819   - Experimental command for instantiation of locales in proof contexts:
  5820         instantiate <label>[<attrs>]: <loc>
  5821     Instantiates locale <loc> and adds all its theorems to the current context
  5822     taking into account their attributes.  Label and attrs are optional
  5823     modifiers, like in theorem declarations.  If present, names of
  5824     instantiated theorems are qualified with <label>, and the attributes
  5825     <attrs> are applied after any attributes these theorems might have already.
  5826       If the locale has assumptions, a chained fact of the form
  5827     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5828     are derived.  The command does not support old-style locales declared
  5829     with "locale (open)".
  5830       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5831 
  5832 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5833   (Isar) contexts.
  5834 
  5835 
  5836 *** HOL ***
  5837 
  5838 * Proof import: new image HOL4 contains the imported library from
  5839   the HOL4 system with about 2500 theorems. It is imported by
  5840   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5841   can be used like any other Isabelle image.  See
  5842   HOL/Import/HOL/README for more information.
  5843 
  5844 * Simplifier:
  5845   - Much improved handling of linear and partial orders.
  5846     Reasoners for linear and partial orders are set up for type classes
  5847     "linorder" and "order" respectively, and are added to the default simpset
  5848     as solvers.  This means that the simplifier can build transitivity chains
  5849     to solve goals from the assumptions.
  5850   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5851     of blast or auto after simplification become unnecessary because the goal
  5852     is solved by simplification already.
  5853 
  5854 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5855     all proved in axiomatic type classes for semirings, rings and fields.
  5856 
  5857 * Numerics:
  5858   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5859     now formalized using the Ring_and_Field theory mentioned above.
  5860   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5861     than before, because now they are set up once in a generic manner.
  5862   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5863     Look for the general versions in Ring_and_Field (and Power if they concern
  5864     exponentiation).
  5865 
  5866 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5867 
  5868 * Records:
  5869   - Record types are now by default printed with their type abbreviation
  5870     instead of the list of all field types. This can be configured via
  5871     the reference "print_record_type_abbr".
  5872   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5873     (not enabled by default).
  5874   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5875     EX x. x = sel r to True (not enabled by default).
  5876   - Tactic "record_split_simp_tac" to split and simplify records added.
  5877 
  5878 * 'specification' command added, allowing for definition by
  5879   specification.  There is also an 'ax_specification' command that
  5880   introduces the new constants axiomatically.
  5881 
  5882 * arith(_tac) is now able to generate counterexamples for reals as well.
  5883 
  5884 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5885 
  5886 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5887   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5888 
  5889 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5890   matrix theory to linear programming.
  5891 
  5892 * Unions and Intersections:
  5893   The latex output syntax of UN and INT has been changed
  5894   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5895   i.e. the index formulae has become a subscript.
  5896   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5897 
  5898 * Unions and Intersections over Intervals:
  5899   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5900   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5901   like in normal math, and corresponding versions for < and for intersection.
  5902 
  5903 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5904   lexicographic dictonary ordering has been added as "lexord".
  5905 
  5906 * ML: the legacy theory structures Int and List have been removed. They had
  5907   conflicted with ML Basis Library structures having the same names.
  5908 
  5909 * 'refute' command added to search for (finite) countermodels.  Only works
  5910   for a fragment of HOL.  The installation of an external SAT solver is
  5911   highly recommended.  See "HOL/Refute.thy" for details.
  5912 
  5913 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5914   formulae under an assignment of free variables to random values.
  5915   In contrast to 'refute', it can deal with inductive datatypes,
  5916   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5917   for examples.
  5918 
  5919 
  5920 *** HOLCF ***
  5921 
  5922 * Streams now come with concatenation and are part of the HOLCF image
  5923 
  5924 
  5925 
  5926 New in Isabelle2003 (May 2003)
  5927 ------------------------------
  5928 
  5929 *** General ***
  5930 
  5931 * Provers/simplifier:
  5932 
  5933   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5934     Assumptions are now subject to complete mutual simplification,
  5935     not just from left to right. The simplifier now preserves
  5936     the order of assumptions.
  5937 
  5938     Potential INCOMPATIBILITY:
  5939 
  5940     -- simp sometimes diverges where the old version did
  5941        not, e.g. invoking simp on the goal
  5942 
  5943         [| P (f x); y = x; f x = f y |] ==> Q
  5944 
  5945        now gives rise to the infinite reduction sequence
  5946 
  5947         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5948 
  5949        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5950        kind of problem.
  5951 
  5952     -- Tactics combining classical reasoner and simplification (such as auto)
  5953        are also affected by this change, because many of them rely on
  5954        simp. They may sometimes diverge as well or yield a different numbers
  5955        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5956        in case of problems. Sometimes subsequent calls to the classical
  5957        reasoner will fail because a preceeding call to the simplifier too
  5958        eagerly simplified the goal, e.g. deleted redundant premises.
  5959 
  5960   - The simplifier trace now shows the names of the applied rewrite rules
  5961 
  5962   - You can limit the number of recursive invocations of the simplifier
  5963     during conditional rewriting (where the simplifie tries to solve the
  5964     conditions before applying the rewrite rule):
  5965     ML "simp_depth_limit := n"
  5966     where n is an integer. Thus you can force termination where previously
  5967     the simplifier would diverge.
  5968 
  5969   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5970 
  5971   - No longer aborts on failed congruence proof.  Instead, the
  5972     congruence is ignored.
  5973 
  5974 * Pure: New generic framework for extracting programs from constructive
  5975   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5976   as HOL/Extraction for some case studies.
  5977 
  5978 * Pure: The main goal of the proof state is no longer shown by default, only
  5979 the subgoals. This behaviour is controlled by a new flag.
  5980    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5981 (ML: Proof.show_main_goal).
  5982 
  5983 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5984 rules whose conclusion matches subgoal 1:
  5985       PG menu: Isabelle/Isar -> Show me -> matching rules
  5986 The rules are ordered by how closely they match the subgoal.
  5987 In particular, rules that solve a subgoal outright are displayed first
  5988 (or rather last, the way they are printed).
  5989 (ML: ProofGeneral.print_intros())
  5990 
  5991 * Pure: New flag trace_unify_fail causes unification to print
  5992 diagnostic information (PG: in trace buffer) when it fails. This is
  5993 useful for figuring out why single step proofs like rule, erule or
  5994 assumption failed.
  5995 
  5996 * Pure: Locale specifications now produce predicate definitions
  5997 according to the body of text (covering assumptions modulo local
  5998 definitions); predicate "loc_axioms" covers newly introduced text,
  5999 while "loc" is cumulative wrt. all included locale expressions; the
  6000 latter view is presented only on export into the global theory
  6001 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  6002 on the old view without predicates;
  6003 
  6004 * Pure: predefined locales "var" and "struct" are useful for sharing
  6005 parameters (as in CASL, for example); just specify something like
  6006 ``var x + var y + struct M'' as import;
  6007 
  6008 * Pure: improved thms_containing: proper indexing of facts instead of
  6009 raw theorems; check validity of results wrt. current name space;
  6010 include local facts of proof configuration (also covers active
  6011 locales), cover fixed variables in index; may use "_" in term
  6012 specification; an optional limit for the number of printed facts may
  6013 be given (the default is 40);
  6014 
  6015 * Pure: disallow duplicate fact bindings within new-style theory files
  6016 (batch-mode only);
  6017 
  6018 * Provers: improved induct method: assumptions introduced by case
  6019 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  6020 the goal statement); "foo" still refers to all facts collectively;
  6021 
  6022 * Provers: the function blast.overloaded has been removed: all constants
  6023 are regarded as potentially overloaded, which improves robustness in exchange
  6024 for slight decrease in efficiency;
  6025 
  6026 * Provers/linorder: New generic prover for transitivity reasoning over
  6027 linear orders.  Note: this prover is not efficient!
  6028 
  6029 * Isar: preview of problems to finish 'show' now produce an error
  6030 rather than just a warning (in interactive mode);
  6031 
  6032 
  6033 *** HOL ***
  6034 
  6035 * arith(_tac)
  6036 
  6037  - Produces a counter example if it cannot prove a goal.
  6038    Note that the counter example may be spurious if the goal is not a formula
  6039    of quantifier-free linear arithmetic.
  6040    In ProofGeneral the counter example appears in the trace buffer.
  6041 
  6042  - Knows about div k and mod k where k is a numeral of type nat or int.
  6043 
  6044  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  6045    linear arithmetic fails. This takes account of quantifiers and divisibility.
  6046    Presburger arithmetic can also be called explicitly via presburger(_tac).
  6047 
  6048 * simp's arithmetic capabilities have been enhanced a bit: it now
  6049 takes ~= in premises into account (by performing a case split);
  6050 
  6051 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  6052 are distributed over a sum of terms;
  6053 
  6054 * New tactic "trans_tac" and method "trans" instantiate
  6055 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  6056 "<=", "<" and "=").
  6057 
  6058 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  6059 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  6060 
  6061 * 'typedef' command has new option "open" to suppress the set
  6062 definition;
  6063 
  6064 * functions Min and Max on finite sets have been introduced (theory
  6065 Finite_Set);
  6066 
  6067 * attribute [symmetric] now works for relations as well; it turns
  6068 (x,y) : R^-1 into (y,x) : R, and vice versa;
  6069 
  6070 * induct over a !!-quantified statement (say !!x1..xn):
  6071   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  6072 
  6073 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  6074 %x. None. Warning: empty_def now refers to the previously hidden definition
  6075 of the empty set.
  6076 
  6077 * Algebra: formalization of classical algebra.  Intended as base for
  6078 any algebraic development in Isabelle.  Currently covers group theory
  6079 (up to Sylow's theorem) and ring theory (Universal Property of
  6080 Univariate Polynomials).  Contributions welcome;
  6081 
  6082 * GroupTheory: deleted, since its material has been moved to Algebra;
  6083 
  6084 * Complex: new directory of the complex numbers with numeric constants,
  6085 nonstandard complex numbers, and some complex analysis, standard and
  6086 nonstandard (Jacques Fleuriot);
  6087 
  6088 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  6089 
  6090 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  6091 Fleuriot);
  6092 
  6093 * Real/HahnBanach: updated and adapted to locales;
  6094 
  6095 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  6096 Gray and Kramer);
  6097 
  6098 * UNITY: added the Meier-Sanders theory of progress sets;
  6099 
  6100 * MicroJava: bytecode verifier and lightweight bytecode verifier
  6101 as abstract algorithms, instantiated to the JVM;
  6102 
  6103 * Bali: Java source language formalization. Type system, operational
  6104 semantics, axiomatic semantics. Supported language features:
  6105 classes, interfaces, objects,virtual methods, static methods,
  6106 static/instance fields, arrays, access modifiers, definite
  6107 assignment, exceptions.
  6108 
  6109 
  6110 *** ZF ***
  6111 
  6112 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  6113 universe, etc.);
  6114 
  6115 * Main ZF: virtually all theories converted to new-style format;
  6116 
  6117 
  6118 *** ML ***
  6119 
  6120 * Pure: Tactic.prove provides sane interface for internal proofs;
  6121 omits the infamous "standard" operation, so this is more appropriate
  6122 than prove_goalw_cterm in many situations (e.g. in simprocs);
  6123 
  6124 * Pure: improved error reporting of simprocs;
  6125 
  6126 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  6127 up simprocs;
  6128 
  6129 
  6130 *** Document preparation ***
  6131 
  6132 * uses \par instead of \\ for line breaks in theory text. This may
  6133 shift some page breaks in large documents. To get the old behaviour
  6134 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  6135 
  6136 * minimized dependencies of isabelle.sty and isabellesym.sty on
  6137 other packages
  6138 
  6139 * \<euro> now needs package babel/greek instead of marvosym (which
  6140 broke \Rightarrow)
  6141 
  6142 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  6143 textcomp package)
  6144 
  6145 
  6146 
  6147 New in Isabelle2002 (March 2002)
  6148 --------------------------------
  6149 
  6150 *** Document preparation ***
  6151 
  6152 * greatly simplified document preparation setup, including more
  6153 graceful interpretation of isatool usedir -i/-d/-D options, and more
  6154 instructive isatool mkdir; users should basically be able to get
  6155 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  6156 users may run a separate document processing stage manually like this:
  6157 "isatool usedir -D output HOL Test && isatool document Test/output";
  6158 
  6159 * theory dependency graph may now be incorporated into documents;
  6160 isatool usedir -g true will produce session_graph.eps/.pdf for use
  6161 with \includegraphics of LaTeX;
  6162 
  6163 * proper spacing of consecutive markup elements, especially text
  6164 blocks after section headings;
  6165 
  6166 * support bold style (for single symbols only), input syntax is like
  6167 this: "\<^bold>\<alpha>" or "\<^bold>A";
  6168 
  6169 * \<bullet> is now output as bold \cdot by default, which looks much
  6170 better in printed text;
  6171 
  6172 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  6173 note that these symbols are currently unavailable in Proof General /
  6174 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  6175 
  6176 * isatool latex no longer depends on changed TEXINPUTS, instead
  6177 isatool document copies the Isabelle style files to the target
  6178 location;
  6179 
  6180 
  6181 *** Isar ***
  6182 
  6183 * Pure/Provers: improved proof by cases and induction;
  6184   - 'case' command admits impromptu naming of parameters (such as
  6185     "case (Suc n)");
  6186   - 'induct' method divinates rule instantiation from the inductive
  6187     claim; no longer requires excessive ?P bindings for proper
  6188     instantiation of cases;
  6189   - 'induct' method properly enumerates all possibilities of set/type
  6190     rules; as a consequence facts may be also passed through *type*
  6191     rules without further ado;
  6192   - 'induct' method now derives symbolic cases from the *rulified*
  6193     rule (before it used to rulify cases stemming from the internal
  6194     atomized version); this means that the context of a non-atomic
  6195     statement becomes is included in the hypothesis, avoiding the
  6196     slightly cumbersome show "PROP ?case" form;
  6197   - 'induct' may now use elim-style induction rules without chaining
  6198     facts, using ``missing'' premises from the goal state; this allows
  6199     rules stemming from inductive sets to be applied in unstructured
  6200     scripts, while still benefitting from proper handling of non-atomic
  6201     statements; NB: major inductive premises need to be put first, all
  6202     the rest of the goal is passed through the induction;
  6203   - 'induct' proper support for mutual induction involving non-atomic
  6204     rule statements (uses the new concept of simultaneous goals, see
  6205     below);
  6206   - append all possible rule selections, but only use the first
  6207     success (no backtracking);
  6208   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  6209   - undeclared rule case names default to numbers 1, 2, 3, ...;
  6210   - added 'print_induct_rules' (covered by help item in recent Proof
  6211     General versions);
  6212   - moved induct/cases attributes to Pure, methods to Provers;
  6213   - generic method setup instantiated for FOL and HOL;
  6214 
  6215 * Pure: support multiple simultaneous goal statements, for example
  6216 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  6217 meta-level mechanism, this acts as if several individual goals had
  6218 been stated separately; in particular common proof methods need to be
  6219 repeated in order to cover all claims; note that a single elimination
  6220 step is *not* sufficient to establish the two conjunctions, so this
  6221 fails:
  6222 
  6223   assume "A & B" then have A and B ..   (*".." fails*)
  6224 
  6225 better use "obtain" in situations as above; alternative refer to
  6226 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  6227 
  6228 * Pure: proper integration with ``locales''; unlike the original
  6229 version by Florian Kammller, Isar locales package high-level proof
  6230 contexts rather than raw logical ones (e.g. we admit to include