NEWS
author huffman
Tue Aug 02 08:28:34 2011 -0700 (2011-08-02)
changeset 44019 ee784502aed5
parent 44018 d34f0cd62164
child 44023 3e5f8cc666db
permissions -rw-r--r--
Extended_Nat.thy: renamed iSuc to eSuc, standardized theorem names
     1 Isabelle NEWS -- history user-relevant changes
     2 ==============================================
     3 
     4 New in this Isabelle version
     5 ----------------------------
     6 
     7 *** General ***
     8 
     9 * Theory loader: source files are identified by content via SHA1
    10 digests.  Discontinued former path/modtime identification and optional
    11 ISABELLE_FILE_IDENT plugin scripts.
    12 
    13 * Parallelization of nested Isar proofs is subject to
    14 Goal.parallel_proofs_threshold (default 100).  See also isabelle
    15 usedir option -Q.
    16 
    17 * Discontinued support for Poly/ML 5.2, which was the last version
    18 without proper multithreading and TimeLimit implementation.
    19 
    20 * Discontinued old lib/scripts/polyml-platform, which has been
    21 obsolete since Isabelle2009-2.
    22 
    23 * Theory loader: source files are exclusively located via the master
    24 directory of each theory node (where the .thy file itself resides).
    25 The global load path (such as src/HOL/Library) has been discontinued.
    26 Note that the path element ~~ may be used to reference theories in the
    27 Isabelle home folder -- for instance, "~~/src/HOL/Library/FuncSet".
    28 INCOMPATIBILITY.
    29 
    30 * Various optional external tools are referenced more robustly and
    31 uniformly by explicit Isabelle settings as follows:
    32 
    33   ISABELLE_CSDP   (formerly CSDP_EXE)
    34   ISABELLE_GHC    (formerly EXEC_GHC or GHC_PATH)
    35   ISABELLE_OCAML  (formerly EXEC_OCAML)
    36   ISABELLE_SWIPL  (formerly EXEC_SWIPL)
    37   ISABELLE_YAP    (formerly EXEC_YAP)
    38 
    39 Note that automated detection from the file-system or search path has
    40 been discontinued.  INCOMPATIBILITY.
    41 
    42 * Name space: former unsynchronized references are now proper
    43 configuration options, with more conventional names:
    44 
    45   long_names   ~> names_long
    46   short_names  ~> names_short
    47   unique_names ~> names_unique
    48 
    49 Minor INCOMPATIBILITY, need to declare options in context like this:
    50 
    51   declare [[names_unique = false]]
    52 
    53 * Literal facts `prop` may contain dummy patterns, e.g. `_ = _`.  Note
    54 that the result needs to be unique, which means fact specifications
    55 may have to be refined after enriching a proof context.
    56 
    57 * Isabelle/Isar reference manual provides more formal references in
    58 syntax diagrams.
    59 
    60 
    61 *** HOL ***
    62 
    63 * Classes bot and top require underlying partial order rather than preorder:
    64 uniqueness of bot and top is guaranteed.  INCOMPATIBILITY.
    65 
    66 * Class complete_lattice: generalized a couple of lemmas from sets;
    67 generalized theorems INF_cong and SUP_cong.  New type classes for complete
    68 boolean algebras and complete linear orders.  Lemmas Inf_less_iff,
    69 less_Sup_iff, INF_less_iff, less_SUP_iff now reside in class complete_linorder.
    70 More consistent and less misunderstandable names:
    71   INFI_def ~> INF_def
    72   SUPR_def ~> SUP_def
    73   le_SUPI ~> le_SUP_I
    74   le_SUPI2 ~> le_SUP_I2
    75   le_INFI ~> le_INF_I
    76   INFI_bool_eq ~> INF_bool_eq
    77   SUPR_bool_eq ~> SUP_bool_eq
    78   INFI_apply ~> INF_apply
    79   SUPR_apply ~> SUP_apply
    80 INCOMPATIBILITY.
    81 
    82 * Theorem collections ball_simps and bex_simps do not contain theorems referring
    83 to UNION any longer;  these have been moved to collection UN_ball_bex_simps.
    84 INCOMPATIBILITY.
    85 
    86 * Archimedean_Field.thy:
    87     floor now is defined as parameter of a separate type class floor_ceiling.
    88  
    89 * Finite_Set.thy: more coherent development of fold_set locales:
    90 
    91     locale fun_left_comm ~> locale comp_fun_commute
    92     locale fun_left_comm_idem ~> locale comp_fun_idem
    93     
    94 Both use point-free characterisation; interpretation proofs may need adjustment.
    95 INCOMPATIBILITY.
    96 
    97 * Code generation:
    98   - theory Library/Code_Char_ord provides native ordering of characters
    99     in the target language.
   100   - commands code_module and code_library are legacy, use export_code instead. 
   101   - evaluator "SML" and method evaluation are legacy, use evaluator "code"
   102     and method eval instead.
   103   
   104 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
   105 
   106 * Nitpick:
   107   - Added "need" and "total_consts" options.
   108   - Reintroduced "show_skolems" option by popular demand.
   109   - Renamed attribute: nitpick_def ~> nitpick_unfold.
   110     INCOMPATIBILITY.
   111 
   112 * Sledgehammer:
   113   - sledgehammer available_provers ~> sledgehammer supported_provers.
   114     INCOMPATIBILITY.
   115   - Added support for SNARK and ToFoF-E on SystemOnTPTP and for simply typed
   116     TPTP problems (TFF).
   117   - Added "preplay_timeout", "slicing", "type_enc", "sound", "max_mono_iters",
   118     and "max_new_mono_instances" options.
   119   - Removed "explicit_apply" and "full_types" options as well as "Full Types"
   120     Proof General menu item. INCOMPATIBILITY.
   121 
   122 * Metis:
   123   - Removed "metisF" -- use "metis" instead. INCOMPATIBILITY.
   124   - Obsoleted "metisFT" -- use "metis (full_types)" instead. INCOMPATIBILITY.
   125 
   126 * "try":
   127   - Renamed "try_methods" and added "simp:", "intro:", "dest:", and "elim:"
   128     options. INCOMPATIBILITY.
   129   - Introduced "try" that not only runs "try_methods" but also "solve_direct",
   130     "sledgehammer", "quickcheck", and "nitpick".
   131 
   132 * Quickcheck:
   133   - Added "eval" option to evaluate terms for the found counterexample
   134     (currently only supported by the default (exhaustive) tester)
   135   - Added post-processing of terms to obtain readable counterexamples
   136     (currently only supported by the default (exhaustive) tester)
   137   - New counterexample generator quickcheck[narrowing] enables
   138     narrowing-based testing.
   139     It requires that the Glasgow Haskell compiler is installed and
   140     its location is known to Isabelle with the environment variable
   141     ISABELLE_GHC.
   142   - Removed quickcheck tester "SML" based on the SML code generator
   143     from HOL-Library
   144 
   145 * Function package: discontinued option "tailrec".
   146 INCOMPATIBILITY. Use partial_function instead.
   147 
   148 * HOL-Probability:
   149   - Caratheodory's extension lemma is now proved for ring_of_sets.
   150   - Infinite products of probability measures are now available.
   151   - Use extended reals instead of positive extended reals.
   152     INCOMPATIBILITY.
   153 
   154 * Old recdef package has been moved to Library/Old_Recdef.thy, where it
   155 must be loaded explicitly.  INCOMPATIBILITY.
   156 
   157 * Well-founded recursion combinator "wfrec" has been moved to
   158 Library/Wfrec.thy. INCOMPATIBILITY.
   159 
   160 * Theory Library/Nat_Infinity has been renamed to Library/Extended_Nat.
   161 The names of the following types and constants have changed:
   162   inat (type) ~> enat
   163   Fin         ~> enat
   164   Infty       ~> infinity (overloaded)
   165   iSuc        ~> eSuc
   166   the_Fin     ~> the_enat
   167 Every theorem name containing "inat", "Fin", "Infty", or "iSuc" has
   168 been renamed accordingly.
   169 
   170 
   171 *** Document preparation ***
   172 
   173 * Discontinued special treatment of hard tabulators, which are better
   174 avoided in the first place.  Implicit tab-width is 1.
   175 
   176 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
   177 isar-ref manual.
   178 
   179 * Antiquotation @{value} evaluates the given term and presents its result.
   180 
   181 * Localized \isabellestyle switch can be used within blocks or groups
   182 like this:
   183 
   184   \isabellestyle{it}  %preferred default
   185   {\isabellestylett @{text "typewriter stuff"}}
   186 
   187 * New term style "isub" as ad-hoc conversion of variables x1, y23 into
   188 subscripted form x\<^isub>1, y\<^isub>2\<^isub>3.
   189 
   190 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
   191 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
   192 
   193 
   194 *** ML ***
   195 
   196 * The inner syntax of sort/type/term/prop supports inlined YXML
   197 representations within quoted string tokens.  By encoding logical
   198 entities via Term_XML (in ML or Scala) concrete syntax can be
   199 bypassed, which is particularly useful for producing bits of text
   200 under external program control.
   201 
   202 * Antiquotations for ML and document preparation are managed as theory
   203 data, which requires explicit setup.
   204 
   205 * Isabelle_Process.is_active allows tools to check if the official
   206 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
   207 (better known as Proof General).
   208 
   209 * Structure Proof_Context follows standard naming scheme.  Old
   210 ProofContext is still available for some time as legacy alias.
   211 
   212 * Structure Timing provides various operations for timing; supersedes
   213 former start_timing/end_timing etc.
   214 
   215 * Path.print is the official way to show file-system paths to users
   216 (including quotes etc.).
   217 
   218 * Inner syntax: identifiers in parse trees of generic categories
   219 "logic", "aprop", "idt" etc. carry position information (disguised as
   220 type constraints).  Occasional INCOMPATIBILITY with non-compliant
   221 translations that choke on unexpected type constraints.  Positions can
   222 be stripped in ML translations via Syntax.strip_positions /
   223 Syntax.strip_positions_ast, or via the syntax constant
   224 "_strip_positions" within parse trees.  As last resort, positions can
   225 be disabled via the configuration option Syntax.positions, which is
   226 called "syntax_positions" in Isar attribute syntax.
   227 
   228 * Discontinued special status of various ML structures that contribute
   229 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
   230 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
   231 refer directly to Ast.Constant, Lexicon.is_identifier,
   232 Syntax_Trans.mk_binder_tr etc.
   233 
   234 * Typed print translation: discontinued show_sorts argument, which is
   235 already available via context of "advanced" translation.
   236 
   237 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
   238 goal states; body tactic needs to address all subgoals uniformly.
   239 
   240 * Slightly more special eq_list/eq_set, with shortcut involving
   241 pointer equality (assumes that eq relation is reflexive).
   242 
   243 * Classical tactics use proper Proof.context instead of historic types
   244 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
   245 operate directly on Proof.context.  Raw type claset retains its use as
   246 snapshot of the classical context, which can be recovered via
   247 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
   248 INCOMPATIBILITY, classical tactics and derived proof methods require
   249 proper Proof.context.
   250 
   251 * Scala layer provides JVM method invocation service for static
   252 methods of type (String)String, see Invoke_Scala.method in ML.
   253 For example:
   254 
   255   Invoke_Scala.method "java.lang.System.getProperty" "java.home"
   256 
   257 
   258 
   259 New in Isabelle2011 (January 2011)
   260 ----------------------------------
   261 
   262 *** General ***
   263 
   264 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
   265 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
   266 useful tooltips and hyperlinks produced from its static analysis.  The
   267 bundled component provides an executable Isabelle tool that can be run
   268 like this:
   269 
   270   Isabelle2011/bin/isabelle jedit
   271 
   272 * Significantly improved Isabelle/Isar implementation manual.
   273 
   274 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
   275 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
   276 while the default heap location within that directory lacks that extra
   277 suffix.  This isolates multiple Isabelle installations from each
   278 other, avoiding problems with old settings in new versions.
   279 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
   280 
   281 * Source files are always encoded as UTF-8, instead of old-fashioned
   282 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   283 the following package declarations:
   284 
   285   \usepackage[utf8]{inputenc}
   286   \usepackage{textcomp}
   287 
   288 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   289 a Unicode character is treated as a single symbol, not a sequence of
   290 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   291 contain symbols without further backslash escapes, Unicode can now be
   292 used here as well.  Recall that Symbol.explode in ML provides a
   293 consistent view on symbols, while raw explode (or String.explode)
   294 merely give a byte-oriented representation.
   295 
   296 * Theory loader: source files are primarily located via the master
   297 directory of each theory node (where the .thy file itself resides).
   298 The global load path is still partially available as legacy feature.
   299 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   300 explicit paths, relatively to the theory.
   301 
   302 * Special treatment of ML file names has been discontinued.
   303 Historically, optional extensions .ML or .sml were added on demand --
   304 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   305 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   306 
   307 * Various options that affect pretty printing etc. are now properly
   308 handled within the context via configuration options, instead of
   309 unsynchronized references or print modes.  There are both ML Config.T
   310 entities and Isar declaration attributes to access these.
   311 
   312   ML (Config.T)                 Isar (attribute)
   313 
   314   eta_contract                  eta_contract
   315   show_brackets                 show_brackets
   316   show_sorts                    show_sorts
   317   show_types                    show_types
   318   show_question_marks           show_question_marks
   319   show_consts                   show_consts
   320   show_abbrevs                  show_abbrevs
   321 
   322   Syntax.ast_trace              syntax_ast_trace
   323   Syntax.ast_stat               syntax_ast_stat
   324   Syntax.ambiguity_level        syntax_ambiguity_level
   325 
   326   Goal_Display.goals_limit      goals_limit
   327   Goal_Display.show_main_goal   show_main_goal
   328 
   329   Method.rule_trace             rule_trace
   330 
   331   Thy_Output.display            thy_output_display
   332   Thy_Output.quotes             thy_output_quotes
   333   Thy_Output.indent             thy_output_indent
   334   Thy_Output.source             thy_output_source
   335   Thy_Output.break              thy_output_break
   336 
   337 Note that corresponding "..._default" references in ML may only be
   338 changed globally at the ROOT session setup, but *not* within a theory.
   339 The option "show_abbrevs" supersedes the former print mode
   340 "no_abbrevs" with inverted meaning.
   341 
   342 * More systematic naming of some configuration options.
   343 INCOMPATIBILITY.
   344 
   345   trace_simp  ~>  simp_trace
   346   debug_simp  ~>  simp_debug
   347 
   348 * Support for real valued configuration options, using simplistic
   349 floating-point notation that coincides with the inner syntax for
   350 float_token.
   351 
   352 * Support for real valued preferences (with approximative PGIP type):
   353 front-ends need to accept "pgint" values in float notation.
   354 INCOMPATIBILITY.
   355 
   356 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   357 DejaVu Sans.
   358 
   359 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   360 
   361 
   362 *** Pure ***
   363 
   364 * Command 'type_synonym' (with single argument) replaces somewhat
   365 outdated 'types', which is still available as legacy feature for some
   366 time.
   367 
   368 * Command 'nonterminal' (with 'and' separated list of arguments)
   369 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   370 
   371 * Command 'notepad' replaces former 'example_proof' for
   372 experimentation in Isar without any result.  INCOMPATIBILITY.
   373 
   374 * Locale interpretation commands 'interpret' and 'sublocale' accept
   375 lists of equations to map definitions in a locale to appropriate
   376 entities in the context of the interpretation.  The 'interpretation'
   377 command already provided this functionality.
   378 
   379 * Diagnostic command 'print_dependencies' prints the locale instances
   380 that would be activated if the specified expression was interpreted in
   381 the current context.  Variant "print_dependencies!" assumes a context
   382 without interpretations.
   383 
   384 * Diagnostic command 'print_interps' prints interpretations in proofs
   385 in addition to interpretations in theories.
   386 
   387 * Discontinued obsolete 'global' and 'local' commands to manipulate
   388 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   389 Sign.root_path and Sign.local_path may be applied directly where this
   390 feature is still required for historical reasons.
   391 
   392 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   393 'definition' instead.
   394 
   395 * The "prems" fact, which refers to the accidental collection of
   396 foundational premises in the context, is now explicitly marked as
   397 legacy feature and will be discontinued soon.  Consider using "assms"
   398 of the head statement or reference facts by explicit names.
   399 
   400 * Document antiquotations @{class} and @{type} print classes and type
   401 constructors.
   402 
   403 * Document antiquotation @{file} checks file/directory entries within
   404 the local file system.
   405 
   406 
   407 *** HOL ***
   408 
   409 * Coercive subtyping: functions can be declared as coercions and type
   410 inference will add them as necessary upon input of a term.  Theory
   411 Complex_Main declares real :: nat => real and real :: int => real as
   412 coercions. A coercion function f is declared like this:
   413 
   414   declare [[coercion f]]
   415 
   416 To lift coercions through type constructors (e.g. from nat => real to
   417 nat list => real list), map functions can be declared, e.g.
   418 
   419   declare [[coercion_map map]]
   420 
   421 Currently coercion inference is activated only in theories including
   422 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   423 the configuration option "coercion_enabled", e.g. it can be enabled in
   424 other theories like this:
   425 
   426   declare [[coercion_enabled]]
   427 
   428 * Command 'partial_function' provides basic support for recursive
   429 function definitions over complete partial orders.  Concrete instances
   430 are provided for i) the option type, ii) tail recursion on arbitrary
   431 types, and iii) the heap monad of Imperative_HOL.  See
   432 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   433 for examples.
   434 
   435 * Function package: f.psimps rules are no longer implicitly declared
   436 as [simp].  INCOMPATIBILITY.
   437 
   438 * Datatype package: theorems generated for executable equality (class
   439 "eq") carry proper names and are treated as default code equations.
   440 
   441 * Inductive package: now offers command 'inductive_simps' to
   442 automatically derive instantiated and simplified equations for
   443 inductive predicates, similar to 'inductive_cases'.
   444 
   445 * Command 'enriched_type' allows to register properties of the
   446 functorial structure of types.
   447 
   448 * Improved infrastructure for term evaluation using code generator
   449 techniques, in particular static evaluation conversions.
   450 
   451 * Code generator: Scala (2.8 or higher) has been added to the target
   452 languages.
   453 
   454 * Code generator: globbing constant expressions "*" and "Theory.*"
   455 have been replaced by the more idiomatic "_" and "Theory._".
   456 INCOMPATIBILITY.
   457 
   458 * Code generator: export_code without explicit file declaration prints
   459 to standard output.  INCOMPATIBILITY.
   460 
   461 * Code generator: do not print function definitions for case
   462 combinators any longer.
   463 
   464 * Code generator: simplification with rules determined with
   465 src/Tools/Code/code_simp.ML and method "code_simp".
   466 
   467 * Code generator for records: more idiomatic representation of record
   468 types.  Warning: records are not covered by ancient SML code
   469 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   470 rep_datatype declaration helps to succeed then:
   471 
   472   record 'a foo = ...
   473   ...
   474   rep_datatype foo_ext ...
   475 
   476 * Records: logical foundation type for records does not carry a
   477 '_type' suffix any longer (obsolete due to authentic syntax).
   478 INCOMPATIBILITY.
   479 
   480 * Quickcheck now by default uses exhaustive testing instead of random
   481 testing.  Random testing can be invoked by "quickcheck [random]",
   482 exhaustive testing by "quickcheck [exhaustive]".
   483 
   484 * Quickcheck instantiates polymorphic types with small finite
   485 datatypes by default. This enables a simple execution mechanism to
   486 handle quantifiers and function equality over the finite datatypes.
   487 
   488 * Quickcheck random generator has been renamed from "code" to
   489 "random".  INCOMPATIBILITY.
   490 
   491 * Quickcheck now has a configurable time limit which is set to 30
   492 seconds by default. This can be changed by adding [timeout = n] to the
   493 quickcheck command. The time limit for Auto Quickcheck is still set
   494 independently.
   495 
   496 * Quickcheck in locales considers interpretations of that locale for
   497 counter example search.
   498 
   499 * Sledgehammer:
   500   - Added "smt" and "remote_smt" provers based on the "smt" proof
   501     method. See the Sledgehammer manual for details ("isabelle doc
   502     sledgehammer").
   503   - Renamed commands:
   504     sledgehammer atp_info ~> sledgehammer running_provers
   505     sledgehammer atp_kill ~> sledgehammer kill_provers
   506     sledgehammer available_atps ~> sledgehammer available_provers
   507     INCOMPATIBILITY.
   508   - Renamed options:
   509     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   510     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   511     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   512     (and "ms" and "min" are no longer supported)
   513     INCOMPATIBILITY.
   514 
   515 * Nitpick:
   516   - Renamed options:
   517     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   518     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   519     INCOMPATIBILITY.
   520   - Added support for partial quotient types.
   521   - Added local versions of the "Nitpick.register_xxx" functions.
   522   - Added "whack" option.
   523   - Allow registration of quotient types as codatatypes.
   524   - Improved "merge_type_vars" option to merge more types.
   525   - Removed unsound "fast_descrs" option.
   526   - Added custom symmetry breaking for datatypes, making it possible to reach
   527     higher cardinalities.
   528   - Prevent the expansion of too large definitions.
   529 
   530 * Proof methods "metis" and "meson" now have configuration options
   531 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   532 to diagnose these tools. E.g.
   533 
   534     using [[metis_trace = true]]
   535 
   536 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   537 manually as command 'solve_direct'.
   538 
   539 * The default SMT solver Z3 must be enabled explicitly (due to
   540 licensing issues) by setting the environment variable
   541 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   542 commercial applications, the SMT solver CVC3 is provided as fall-back;
   543 changing the SMT solver is done via the configuration option
   544 "smt_solver".
   545 
   546 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   547 i.e. "remote_cvc3" and "remote_z3".
   548 
   549 * Added basic SMT support for datatypes, records, and typedefs using
   550 the oracle mode (no proofs).  Direct support of pairs has been dropped
   551 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   552 support for a similar behavior).  Minor INCOMPATIBILITY.
   553 
   554 * Changed SMT configuration options:
   555   - Renamed:
   556     z3_proofs ~> smt_oracle (with inverted meaning)
   557     z3_trace_assms ~> smt_trace_used_facts
   558     INCOMPATIBILITY.
   559   - Added:
   560     smt_verbose
   561     smt_random_seed
   562     smt_datatypes
   563     smt_infer_triggers
   564     smt_monomorph_limit
   565     cvc3_options
   566     remote_cvc3_options
   567     remote_z3_options
   568     yices_options
   569 
   570 * Boogie output files (.b2i files) need to be declared in the theory
   571 header.
   572 
   573 * Simplification procedure "list_to_set_comprehension" rewrites list
   574 comprehensions applied to List.set to set comprehensions.  Occasional
   575 INCOMPATIBILITY, may be deactivated like this:
   576 
   577   declare [[simproc del: list_to_set_comprehension]]
   578 
   579 * Removed old version of primrec package.  INCOMPATIBILITY.
   580 
   581 * Removed simplifier congruence rule of "prod_case", as has for long
   582 been the case with "split".  INCOMPATIBILITY.
   583 
   584 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   585 
   586 * Removed [split_format ... and ... and ...] version of
   587 [split_format].  Potential INCOMPATIBILITY.
   588 
   589 * Predicate "sorted" now defined inductively, with nice induction
   590 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   591 
   592 * Constant "contents" renamed to "the_elem", to free the generic name
   593 contents for other uses.  INCOMPATIBILITY.
   594 
   595 * Renamed class eq and constant eq (for code generation) to class
   596 equal and constant equal, plus renaming of related facts and various
   597 tuning.  INCOMPATIBILITY.
   598 
   599 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   600 
   601 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   602 INCOMPATIBILITY.
   603 
   604 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   605 avoid confusion with finite sets.  INCOMPATIBILITY.
   606 
   607 * Abandoned locales equiv, congruent and congruent2 for equivalence
   608 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   609 for congruent(2)).
   610 
   611 * Some previously unqualified names have been qualified:
   612 
   613   types
   614     bool ~> HOL.bool
   615     nat ~> Nat.nat
   616 
   617   constants
   618     Trueprop ~> HOL.Trueprop
   619     True ~> HOL.True
   620     False ~> HOL.False
   621     op & ~> HOL.conj
   622     op | ~> HOL.disj
   623     op --> ~> HOL.implies
   624     op = ~> HOL.eq
   625     Not ~> HOL.Not
   626     The ~> HOL.The
   627     All ~> HOL.All
   628     Ex ~> HOL.Ex
   629     Ex1 ~> HOL.Ex1
   630     Let ~> HOL.Let
   631     If ~> HOL.If
   632     Ball ~> Set.Ball
   633     Bex ~> Set.Bex
   634     Suc ~> Nat.Suc
   635     Pair ~> Product_Type.Pair
   636     fst ~> Product_Type.fst
   637     snd ~> Product_Type.snd
   638     curry ~> Product_Type.curry
   639     op : ~> Set.member
   640     Collect ~> Set.Collect
   641 
   642 INCOMPATIBILITY.
   643 
   644 * More canonical naming convention for some fundamental definitions:
   645 
   646     bot_bool_eq ~> bot_bool_def
   647     top_bool_eq ~> top_bool_def
   648     inf_bool_eq ~> inf_bool_def
   649     sup_bool_eq ~> sup_bool_def
   650     bot_fun_eq  ~> bot_fun_def
   651     top_fun_eq  ~> top_fun_def
   652     inf_fun_eq  ~> inf_fun_def
   653     sup_fun_eq  ~> sup_fun_def
   654 
   655 INCOMPATIBILITY.
   656 
   657 * More stylized fact names:
   658 
   659   expand_fun_eq ~> fun_eq_iff
   660   expand_set_eq ~> set_eq_iff
   661   set_ext       ~> set_eqI
   662   nat_number    ~> eval_nat_numeral
   663 
   664 INCOMPATIBILITY.
   665 
   666 * Refactoring of code-generation specific operations in theory List:
   667 
   668   constants
   669     null ~> List.null
   670 
   671   facts
   672     mem_iff ~> member_def
   673     null_empty ~> null_def
   674 
   675 INCOMPATIBILITY.  Note that these were not supposed to be used
   676 regularly unless for striking reasons; their main purpose was code
   677 generation.
   678 
   679 Various operations from the Haskell prelude are used for generating
   680 Haskell code.
   681 
   682 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   683 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   684 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   685 
   686 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   687 "*" and "+" respectively.  INCOMPATIBILITY.
   688 
   689 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   690 "Sum_Type.Plus" instead.
   691 
   692 * Constant "split" has been merged with constant "prod_case"; names of
   693 ML functions, facts etc. involving split have been retained so far,
   694 though.  INCOMPATIBILITY.
   695 
   696 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   697 instead.  INCOMPATIBILITY.
   698 
   699 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   700 INCOMPATIBILITY.
   701 
   702 * Former theory Library/Enum is now part of the HOL-Main image.
   703 INCOMPATIBILITY: all constants of the Enum theory now have to be
   704 referred to by its qualified name.
   705 
   706   enum    ~>  Enum.enum
   707   nlists  ~>  Enum.nlists
   708   product ~>  Enum.product
   709 
   710 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   711 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   712 INCOMPATIBILITY.
   713 
   714 * Theory Library/SetsAndFunctions has been split into
   715 Library/Function_Algebras and Library/Set_Algebras; canonical names
   716 for instance definitions for functions; various improvements.
   717 INCOMPATIBILITY.
   718 
   719 * Theory Library/Multiset provides stable quicksort implementation of
   720 sort_key.
   721 
   722 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   723 INCOMPATIBILITY.
   724 
   725 * Session Multivariate_Analysis: introduced a type class for euclidean
   726 space.  Most theorems are now stated in terms of euclidean spaces
   727 instead of finite cartesian products.
   728 
   729   types
   730     real ^ 'n ~>  'a::real_vector
   731               ~>  'a::euclidean_space
   732               ~>  'a::ordered_euclidean_space
   733         (depends on your needs)
   734 
   735   constants
   736      _ $ _        ~> _ $$ _
   737      \<chi> x. _  ~> \<chi>\<chi> x. _
   738      CARD('n)     ~> DIM('a)
   739 
   740 Also note that the indices are now natural numbers and not from some
   741 finite type. Finite cartesian products of euclidean spaces, products
   742 of euclidean spaces the real and complex numbers are instantiated to
   743 be euclidean_spaces.  INCOMPATIBILITY.
   744 
   745 * Session Probability: introduced pextreal as positive extended real
   746 numbers.  Use pextreal as value for measures.  Introduce the
   747 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   748 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   749 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   750 
   751 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   752 INCOMPATIBILITY.
   753 
   754 * Session SPARK (with image HOL-SPARK) provides commands to load and
   755 prove verification conditions generated by the SPARK Ada program
   756 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   757 
   758 
   759 *** HOL-Algebra ***
   760 
   761 * Theorems for additive ring operations (locale abelian_monoid and
   762 descendants) are generated by interpretation from their multiplicative
   763 counterparts.  Names (in particular theorem names) have the mandatory
   764 qualifier 'add'.  Previous theorem names are redeclared for
   765 compatibility.
   766 
   767 * Structure "int_ring" is now an abbreviation (previously a
   768 definition).  This fits more natural with advanced interpretations.
   769 
   770 
   771 *** HOLCF ***
   772 
   773 * The domain package now runs in definitional mode by default: The
   774 former command 'new_domain' is now called 'domain'.  To use the domain
   775 package in its original axiomatic mode, use 'domain (unsafe)'.
   776 INCOMPATIBILITY.
   777 
   778 * The new class "domain" is now the default sort.  Class "predomain"
   779 is an unpointed version of "domain". Theories can be updated by
   780 replacing sort annotations as shown below.  INCOMPATIBILITY.
   781 
   782   'a::type ~> 'a::countable
   783   'a::cpo  ~> 'a::predomain
   784   'a::pcpo ~> 'a::domain
   785 
   786 * The old type class "rep" has been superseded by class "domain".
   787 Accordingly, users of the definitional package must remove any
   788 "default_sort rep" declarations.  INCOMPATIBILITY.
   789 
   790 * The domain package (definitional mode) now supports unpointed
   791 predomain argument types, as long as they are marked 'lazy'. (Strict
   792 arguments must be in class "domain".) For example, the following
   793 domain definition now works:
   794 
   795   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   796 
   797 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   798 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   799 'a option, and 'a list.  Additionally, it configures fixrec and the
   800 domain package to work with these types.  For example:
   801 
   802   fixrec isInl :: "('a + 'b) u -> tr"
   803     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   804 
   805   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   806 
   807 * The "(permissive)" option of fixrec has been replaced with a
   808 per-equation "(unchecked)" option. See
   809 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
   810 
   811 * The "bifinite" class no longer fixes a constant "approx"; the class
   812 now just asserts that such a function exists.  INCOMPATIBILITY.
   813 
   814 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
   815 defines an embedding of type 'a defl into udom by default; instances
   816 of "bifinite" and "domain" classes are available in
   817 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
   818 
   819 * The syntax "REP('a)" has been replaced with "DEFL('a)".
   820 
   821 * The predicate "directed" has been removed.  INCOMPATIBILITY.
   822 
   823 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
   824 
   825 * The function "cprod_map" has been renamed to "prod_map".
   826 INCOMPATIBILITY.
   827 
   828 * The monadic bind operator on each powerdomain has new binder syntax
   829 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
   830 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
   831 
   832 * The infix syntax for binary union on each powerdomain has changed
   833 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
   834 syntax.  INCOMPATIBILITY.
   835 
   836 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
   837 still supported as an input translation.
   838 
   839 * Renamed some theorems (the original names are also still available).
   840 
   841   expand_fun_below   ~> fun_below_iff
   842   below_fun_ext      ~> fun_belowI
   843   expand_cfun_eq     ~> cfun_eq_iff
   844   ext_cfun           ~> cfun_eqI
   845   expand_cfun_below  ~> cfun_below_iff
   846   below_cfun_ext     ~> cfun_belowI
   847   cont2cont_Rep_CFun ~> cont2cont_APP
   848 
   849 * The Abs and Rep functions for various types have changed names.
   850 Related theorem names have also changed to match. INCOMPATIBILITY.
   851 
   852   Rep_CFun  ~> Rep_cfun
   853   Abs_CFun  ~> Abs_cfun
   854   Rep_Sprod ~> Rep_sprod
   855   Abs_Sprod ~> Abs_sprod
   856   Rep_Ssum  ~> Rep_ssum
   857   Abs_Ssum  ~> Abs_ssum
   858 
   859 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   860 been renamed to *_bottom_iff.  INCOMPATIBILITY.
   861 
   862 * Various changes to bisimulation/coinduction with domain package:
   863 
   864   - Definitions of "bisim" constants no longer mention definedness.
   865   - With mutual recursion, "bisim" predicate is now curried.
   866   - With mutual recursion, each type gets a separate coind theorem.
   867   - Variable names in bisim_def and coinduct rules have changed.
   868 
   869 INCOMPATIBILITY.
   870 
   871 * Case combinators generated by the domain package for type "foo" are
   872 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
   873 
   874 * Several theorems have been renamed to more accurately reflect the
   875 names of constants and types involved.  INCOMPATIBILITY.
   876 
   877   thelub_const    ~> lub_const
   878   lub_const       ~> is_lub_const
   879   thelubI         ~> lub_eqI
   880   is_lub_lub      ~> is_lubD2
   881   lubI            ~> is_lub_lub
   882   unique_lub      ~> is_lub_unique
   883   is_ub_lub       ~> is_lub_rangeD1
   884   lub_bin_chain   ~> is_lub_bin_chain
   885   lub_fun         ~> is_lub_fun
   886   thelub_fun      ~> lub_fun
   887   thelub_cfun     ~> lub_cfun
   888   thelub_Pair     ~> lub_Pair
   889   lub_cprod       ~> is_lub_prod
   890   thelub_cprod    ~> lub_prod
   891   minimal_cprod   ~> minimal_prod
   892   inst_cprod_pcpo ~> inst_prod_pcpo
   893   UU_I            ~> bottomI
   894   compact_UU      ~> compact_bottom
   895   deflation_UU    ~> deflation_bottom
   896   finite_deflation_UU ~> finite_deflation_bottom
   897 
   898 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
   899 
   900   sq_ord_less_eq_trans ~> below_eq_trans
   901   sq_ord_eq_less_trans ~> eq_below_trans
   902   refl_less            ~> below_refl
   903   trans_less           ~> below_trans
   904   antisym_less         ~> below_antisym
   905   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
   906   box_less             ~> box_below
   907   rev_trans_less       ~> rev_below_trans
   908   not_less2not_eq      ~> not_below2not_eq
   909   less_UU_iff          ~> below_UU_iff
   910   flat_less_iff        ~> flat_below_iff
   911   adm_less             ~> adm_below
   912   adm_not_less         ~> adm_not_below
   913   adm_compact_not_less ~> adm_compact_not_below
   914   less_fun_def         ~> below_fun_def
   915   expand_fun_less      ~> fun_below_iff
   916   less_fun_ext         ~> fun_belowI
   917   less_discr_def       ~> below_discr_def
   918   discr_less_eq        ~> discr_below_eq
   919   less_unit_def        ~> below_unit_def
   920   less_cprod_def       ~> below_prod_def
   921   prod_lessI           ~> prod_belowI
   922   Pair_less_iff        ~> Pair_below_iff
   923   fst_less_iff         ~> fst_below_iff
   924   snd_less_iff         ~> snd_below_iff
   925   expand_cfun_less     ~> cfun_below_iff
   926   less_cfun_ext        ~> cfun_belowI
   927   injection_less       ~> injection_below
   928   less_up_def          ~> below_up_def
   929   not_Iup_less         ~> not_Iup_below
   930   Iup_less             ~> Iup_below
   931   up_less              ~> up_below
   932   Def_inject_less_eq   ~> Def_below_Def
   933   Def_less_is_eq       ~> Def_below_iff
   934   spair_less_iff       ~> spair_below_iff
   935   less_sprod           ~> below_sprod
   936   spair_less           ~> spair_below
   937   sfst_less_iff        ~> sfst_below_iff
   938   ssnd_less_iff        ~> ssnd_below_iff
   939   fix_least_less       ~> fix_least_below
   940   dist_less_one        ~> dist_below_one
   941   less_ONE             ~> below_ONE
   942   ONE_less_iff         ~> ONE_below_iff
   943   less_sinlD           ~> below_sinlD
   944   less_sinrD           ~> below_sinrD
   945 
   946 
   947 *** FOL and ZF ***
   948 
   949 * All constant names are now qualified internally and use proper
   950 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
   951 
   952 
   953 *** ML ***
   954 
   955 * Antiquotation @{assert} inlines a function bool -> unit that raises
   956 Fail if the argument is false.  Due to inlining the source position of
   957 failed assertions is included in the error output.
   958 
   959 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
   960 text is in practice always evaluated with a stable theory checkpoint.
   961 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
   962 
   963 * Antiquotation @{theory A} refers to theory A from the ancestry of
   964 the current context, not any accidental theory loader state as before.
   965 Potential INCOMPATIBILITY, subtle change in semantics.
   966 
   967 * Syntax.pretty_priority (default 0) configures the required priority
   968 of pretty-printed output and thus affects insertion of parentheses.
   969 
   970 * Syntax.default_root (default "any") configures the inner syntax
   971 category (nonterminal symbol) for parsing of terms.
   972 
   973 * Former exception Library.UnequalLengths now coincides with
   974 ListPair.UnequalLengths.
   975 
   976 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
   977 main functionality is provided by structure Simplifier.
   978 
   979 * Renamed raw "explode" function to "raw_explode" to emphasize its
   980 meaning.  Note that internally to Isabelle, Symbol.explode is used in
   981 almost all situations.
   982 
   983 * Discontinued obsolete function sys_error and exception SYS_ERROR.
   984 See implementation manual for further details on exceptions in
   985 Isabelle/ML.
   986 
   987 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   988 meaning.
   989 
   990 * Renamed structure PureThy to Pure_Thy and moved most of its
   991 operations to structure Global_Theory, to emphasize that this is
   992 rarely-used global-only stuff.
   993 
   994 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
   995 instead (or tracing for high-volume output).
   996 
   997 * Configuration option show_question_marks only affects regular pretty
   998 printing of types and terms, not raw Term.string_of_vname.
   999 
  1000 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
  1001 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
  1002 @{thms} for most purposes.
  1003 
  1004 * ML structure Unsynchronized is never opened, not even in Isar
  1005 interaction mode as before.  Old Unsynchronized.set etc. have been
  1006 discontinued -- use plain := instead.  This should be *rare* anyway,
  1007 since modern tools always work via official context data, notably
  1008 configuration options.
  1009 
  1010 * Parallel and asynchronous execution requires special care concerning
  1011 interrupts.  Structure Exn provides some convenience functions that
  1012 avoid working directly with raw Interrupt.  User code must not absorb
  1013 interrupts -- intermediate handling (for cleanup etc.) needs to be
  1014 followed by re-raising of the original exception.  Another common
  1015 source of mistakes are "handle _" patterns, which make the meaning of
  1016 the program subject to physical effects of the environment.
  1017 
  1018 
  1019 
  1020 New in Isabelle2009-2 (June 2010)
  1021 ---------------------------------
  1022 
  1023 *** General ***
  1024 
  1025 * Authentic syntax for *all* logical entities (type classes, type
  1026 constructors, term constants): provides simple and robust
  1027 correspondence between formal entities and concrete syntax.  Within
  1028 the parse tree / AST representations, "constants" are decorated by
  1029 their category (class, type, const) and spelled out explicitly with
  1030 their full internal name.
  1031 
  1032 Substantial INCOMPATIBILITY concerning low-level syntax declarations
  1033 and translations (translation rules and translation functions in ML).
  1034 Some hints on upgrading:
  1035 
  1036   - Many existing uses of 'syntax' and 'translations' can be replaced
  1037     by more modern 'type_notation', 'notation' and 'abbreviation',
  1038     which are independent of this issue.
  1039 
  1040   - 'translations' require markup within the AST; the term syntax
  1041     provides the following special forms:
  1042 
  1043       CONST c   -- produces syntax version of constant c from context
  1044       XCONST c  -- literally c, checked as constant from context
  1045       c         -- literally c, if declared by 'syntax'
  1046 
  1047     Plain identifiers are treated as AST variables -- occasionally the
  1048     system indicates accidental variables via the error "rhs contains
  1049     extra variables".
  1050 
  1051     Type classes and type constructors are marked according to their
  1052     concrete syntax.  Some old translations rules need to be written
  1053     for the "type" category, using type constructor application
  1054     instead of pseudo-term application of the default category
  1055     "logic".
  1056 
  1057   - 'parse_translation' etc. in ML may use the following
  1058     antiquotations:
  1059 
  1060       @{class_syntax c}   -- type class c within parse tree / AST
  1061       @{term_syntax c}    -- type constructor c within parse tree / AST
  1062       @{const_syntax c}   -- ML version of "CONST c" above
  1063       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
  1064 
  1065   - Literal types within 'typed_print_translations', i.e. those *not*
  1066     represented as pseudo-terms are represented verbatim.  Use @{class
  1067     c} or @{type_name c} here instead of the above syntax
  1068     antiquotations.
  1069 
  1070 Note that old non-authentic syntax was based on unqualified base
  1071 names, so all of the above "constant" names would coincide.  Recall
  1072 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
  1073 diagnose syntax problems.
  1074 
  1075 * Type constructors admit general mixfix syntax, not just infix.
  1076 
  1077 * Concrete syntax may be attached to local entities without a proof
  1078 body, too.  This works via regular mixfix annotations for 'fix',
  1079 'def', 'obtain' etc. or via the explicit 'write' command, which is
  1080 similar to the 'notation' command in theory specifications.
  1081 
  1082 * Discontinued unnamed infix syntax (legacy feature for many years) --
  1083 need to specify constant name and syntax separately.  Internal ML
  1084 datatype constructors have been renamed from InfixName to Infix etc.
  1085 Minor INCOMPATIBILITY.
  1086 
  1087 * Schematic theorem statements need to be explicitly markup as such,
  1088 via commands 'schematic_lemma', 'schematic_theorem',
  1089 'schematic_corollary'.  Thus the relevance of the proof is made
  1090 syntactically clear, which impacts performance in a parallel or
  1091 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  1092 
  1093 * Use of cumulative prems via "!" in some proof methods has been
  1094 discontinued (old legacy feature).
  1095 
  1096 * References 'trace_simp' and 'debug_simp' have been replaced by
  1097 configuration options stored in the context. Enabling tracing (the
  1098 case of debugging is similar) in proofs works via
  1099 
  1100   using [[trace_simp = true]]
  1101 
  1102 Tracing is then active for all invocations of the simplifier in
  1103 subsequent goal refinement steps. Tracing may also still be enabled or
  1104 disabled via the ProofGeneral settings menu.
  1105 
  1106 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  1107 'hide_fact' replace the former 'hide' KIND command.  Minor
  1108 INCOMPATIBILITY.
  1109 
  1110 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  1111 more efficient than combinations with -q1 or -q2.
  1112 
  1113 
  1114 *** Pure ***
  1115 
  1116 * Proofterms record type-class reasoning explicitly, using the
  1117 "unconstrain" operation internally.  This eliminates all sort
  1118 constraints from a theorem and proof, introducing explicit
  1119 OFCLASS-premises.  On the proof term level, this operation is
  1120 automatically applied at theorem boundaries, such that closed proofs
  1121 are always free of sort constraints.  INCOMPATIBILITY for tools that
  1122 inspect proof terms.
  1123 
  1124 * Local theory specifications may depend on extra type variables that
  1125 are not present in the result type -- arguments TYPE('a) :: 'a itself
  1126 are added internally.  For example:
  1127 
  1128   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  1129 
  1130 * Predicates of locales introduced by classes carry a mandatory
  1131 "class" prefix.  INCOMPATIBILITY.
  1132 
  1133 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  1134 
  1135 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  1136 'class' instead.
  1137 
  1138 * Command 'code_reflect' allows to incorporate generated ML code into
  1139 runtime environment; replaces immature code_datatype antiquotation.
  1140 INCOMPATIBILITY.
  1141 
  1142 * Code generator: simple concept for abstract datatypes obeying
  1143 invariants.
  1144 
  1145 * Code generator: details of internal data cache have no impact on the
  1146 user space functionality any longer.
  1147 
  1148 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1149 subgoals.  This is more appropriate for interpretations with 'where'.
  1150 INCOMPATIBILITY.
  1151 
  1152 * Command 'example_proof' opens an empty proof body.  This allows to
  1153 experiment with Isar, without producing any persistent result.
  1154 
  1155 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1156 within a local theory context, with explicit checking of the
  1157 constructors involved (in contrast to the raw 'syntax' versions).
  1158 
  1159 * Commands 'types' and 'typedecl' now work within a local theory
  1160 context -- without introducing dependencies on parameters or
  1161 assumptions, which is not possible in Isabelle/Pure.
  1162 
  1163 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1164 within a local theory context.  Minor INCOMPATIBILITY.
  1165 
  1166 
  1167 *** HOL ***
  1168 
  1169 * Command 'typedef' now works within a local theory context -- without
  1170 introducing dependencies on parameters or assumptions, which is not
  1171 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1172 contain multiple interpretations of local typedefs (with different
  1173 non-emptiness proofs), even in a global theory context.
  1174 
  1175 * New package for quotient types.  Commands 'quotient_type' and
  1176 'quotient_definition' may be used for defining types and constants by
  1177 quotient constructions.  An example is the type of integers created by
  1178 quotienting pairs of natural numbers:
  1179 
  1180   fun
  1181     intrel :: "(nat * nat) => (nat * nat) => bool"
  1182   where
  1183     "intrel (x, y) (u, v) = (x + v = u + y)"
  1184 
  1185   quotient_type int = "nat * nat" / intrel
  1186     by (auto simp add: equivp_def expand_fun_eq)
  1187 
  1188   quotient_definition
  1189     "0::int" is "(0::nat, 0::nat)"
  1190 
  1191 The method "lifting" can be used to lift of theorems from the
  1192 underlying "raw" type to the quotient type.  The example
  1193 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1194 construction and provides a reasoning infrastructure for finite sets.
  1195 
  1196 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1197 clash with new theory Quotient in Main HOL.
  1198 
  1199 * Moved the SMT binding into the main HOL session, eliminating
  1200 separate HOL-SMT session.
  1201 
  1202 * List membership infix mem operation is only an input abbreviation.
  1203 INCOMPATIBILITY.
  1204 
  1205 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1206 for future developements; former Library/Word.thy is still present in
  1207 the AFP entry RSAPPS.
  1208 
  1209 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1210 longer shadowed.  INCOMPATIBILITY.
  1211 
  1212 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1213 INCOMPATIBILITY.
  1214 
  1215 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1216 INCOMPATIBILITY.
  1217 
  1218 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1219 instead.  INCOMPATIBILITY.
  1220 
  1221 * Dropped several real-specific versions of lemmas about floor and
  1222 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1223 instead.  INCOMPATIBILITY.
  1224 
  1225   floor_number_of_eq         ~> floor_number_of
  1226   le_floor_eq_number_of      ~> number_of_le_floor
  1227   le_floor_eq_zero           ~> zero_le_floor
  1228   le_floor_eq_one            ~> one_le_floor
  1229   floor_less_eq_number_of    ~> floor_less_number_of
  1230   floor_less_eq_zero         ~> floor_less_zero
  1231   floor_less_eq_one          ~> floor_less_one
  1232   less_floor_eq_number_of    ~> number_of_less_floor
  1233   less_floor_eq_zero         ~> zero_less_floor
  1234   less_floor_eq_one          ~> one_less_floor
  1235   floor_le_eq_number_of      ~> floor_le_number_of
  1236   floor_le_eq_zero           ~> floor_le_zero
  1237   floor_le_eq_one            ~> floor_le_one
  1238   floor_subtract_number_of   ~> floor_diff_number_of
  1239   floor_subtract_one         ~> floor_diff_one
  1240   ceiling_number_of_eq       ~> ceiling_number_of
  1241   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1242   ceiling_le_zero_eq         ~> ceiling_le_zero
  1243   ceiling_le_eq_one          ~> ceiling_le_one
  1244   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1245   less_ceiling_eq_zero       ~> zero_less_ceiling
  1246   less_ceiling_eq_one        ~> one_less_ceiling
  1247   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1248   ceiling_less_eq_zero       ~> ceiling_less_zero
  1249   ceiling_less_eq_one        ~> ceiling_less_one
  1250   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1251   le_ceiling_eq_zero         ~> zero_le_ceiling
  1252   le_ceiling_eq_one          ~> one_le_ceiling
  1253   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1254   ceiling_subtract_one       ~> ceiling_diff_one
  1255 
  1256 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1257 application of the various fold combinators on finite sets.
  1258 
  1259 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1260 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1261 implementation.  INCOMPATIBILTY.
  1262 
  1263 * Theory Library/Coinductive_List has been removed -- superseded by
  1264 AFP/thys/Coinductive.
  1265 
  1266 * Theory PReal, including the type "preal" and related operations, has
  1267 been removed.  INCOMPATIBILITY.
  1268 
  1269 * Real: new development using Cauchy Sequences.
  1270 
  1271 * Split off theory "Big_Operators" containing setsum, setprod,
  1272 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1273 
  1274 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1275 "Int" etc.  INCOMPATIBILITY.
  1276 
  1277 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1278 
  1279 * New set of rules "ac_simps" provides combined assoc / commute
  1280 rewrites for all interpretations of the appropriate generic locales.
  1281 
  1282 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1283 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1284 appropriate and more consistent names suitable for name prefixes
  1285 within the HOL theories.  INCOMPATIBILITY.
  1286 
  1287 * Some generic constants have been put to appropriate theories:
  1288   - less_eq, less: Orderings
  1289   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1290   - inverse, divide: Rings
  1291 INCOMPATIBILITY.
  1292 
  1293 * More consistent naming of type classes involving orderings (and
  1294 lattices):
  1295 
  1296     lower_semilattice                   ~> semilattice_inf
  1297     upper_semilattice                   ~> semilattice_sup
  1298 
  1299     dense_linear_order                  ~> dense_linorder
  1300 
  1301     pordered_ab_group_add               ~> ordered_ab_group_add
  1302     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1303     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1304     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1305     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1306     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1307     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1308     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1309     pordered_comm_ring                  ~> ordered_comm_ring
  1310     pordered_comm_semiring              ~> ordered_comm_semiring
  1311     pordered_ring                       ~> ordered_ring
  1312     pordered_ring_abs                   ~> ordered_ring_abs
  1313     pordered_semiring                   ~> ordered_semiring
  1314 
  1315     ordered_ab_group_add                ~> linordered_ab_group_add
  1316     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1317     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1318     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1319     ordered_field                       ~> linordered_field
  1320     ordered_field_no_lb                 ~> linordered_field_no_lb
  1321     ordered_field_no_ub                 ~> linordered_field_no_ub
  1322     ordered_field_dense_linear_order    ~> dense_linordered_field
  1323     ordered_idom                        ~> linordered_idom
  1324     ordered_ring                        ~> linordered_ring
  1325     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1326     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1327     ordered_ring_strict                 ~> linordered_ring_strict
  1328     ordered_semidom                     ~> linordered_semidom
  1329     ordered_semiring                    ~> linordered_semiring
  1330     ordered_semiring_1                  ~> linordered_semiring_1
  1331     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1332     ordered_semiring_strict             ~> linordered_semiring_strict
  1333 
  1334   The following slightly odd type classes have been moved to a
  1335   separate theory Library/Lattice_Algebras:
  1336 
  1337     lordered_ab_group_add               ~> lattice_ab_group_add
  1338     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1339     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1340     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1341     lordered_ring                       ~> lattice_ring
  1342 
  1343 INCOMPATIBILITY.
  1344 
  1345 * Refined field classes:
  1346   - classes division_ring_inverse_zero, field_inverse_zero,
  1347     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1348     subsumes former division_by_zero class;
  1349   - numerous lemmas have been ported from field to division_ring.
  1350 INCOMPATIBILITY.
  1351 
  1352 * Refined algebra theorem collections:
  1353   - dropped theorem group group_simps, use algebra_simps instead;
  1354   - dropped theorem group ring_simps, use field_simps instead;
  1355   - proper theorem collection field_simps subsumes former theorem
  1356     groups field_eq_simps and field_simps;
  1357   - dropped lemma eq_minus_self_iff which is a duplicate for
  1358     equal_neg_zero.
  1359 INCOMPATIBILITY.
  1360 
  1361 * Theory Finite_Set and List: some lemmas have been generalized from
  1362 sets to lattices:
  1363 
  1364   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1365   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1366   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1367   union_Union_fold_union        ~> sup_Sup_fold_sup
  1368   Inter_fold_inter              ~> Inf_fold_inf
  1369   Union_fold_union              ~> Sup_fold_sup
  1370   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1371   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1372   INTER_fold_inter              ~> INFI_fold_inf
  1373   UNION_fold_union              ~> SUPR_fold_sup
  1374 
  1375 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1376 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1377 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1378 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1379 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1380 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1381 
  1382 * Reorganized theory Multiset: swapped notation of pointwise and
  1383 multiset order:
  1384 
  1385   - pointwise ordering is instance of class order with standard syntax
  1386     <= and <;
  1387   - multiset ordering has syntax <=# and <#; partial order properties
  1388     are provided by means of interpretation with prefix
  1389     multiset_order;
  1390   - less duplication, less historical organization of sections,
  1391     conversion from associations lists to multisets, rudimentary code
  1392     generation;
  1393   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1394     if needed.
  1395 
  1396 Renamed:
  1397 
  1398   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1399   multi_count_ext  ~>  multiset_ext
  1400   diff_union_inverse2  ~>  diff_union_cancelR
  1401 
  1402 INCOMPATIBILITY.
  1403 
  1404 * Theory Permutation: replaced local "remove" by List.remove1.
  1405 
  1406 * Code generation: ML and OCaml code is decorated with signatures.
  1407 
  1408 * Theory List: added transpose.
  1409 
  1410 * Library/Nat_Bijection.thy is a collection of bijective functions
  1411 between nat and other types, which supersedes the older libraries
  1412 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1413 
  1414   Constants:
  1415   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1416   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1417   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1418   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1419   Countable.pair_encode           ~> prod_encode
  1420   NatIso.prod2nat                 ~> prod_encode
  1421   NatIso.nat2prod                 ~> prod_decode
  1422   NatIso.sum2nat                  ~> sum_encode
  1423   NatIso.nat2sum                  ~> sum_decode
  1424   NatIso.list2nat                 ~> list_encode
  1425   NatIso.nat2list                 ~> list_decode
  1426   NatIso.set2nat                  ~> set_encode
  1427   NatIso.nat2set                  ~> set_decode
  1428 
  1429   Lemmas:
  1430   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1431   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1432   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1433   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1434   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1435   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1436   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1437   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1438   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1439   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1440   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1441   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1442   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1443 
  1444 * Sledgehammer:
  1445   - Renamed ATP commands:
  1446     atp_info     ~> sledgehammer running_atps
  1447     atp_kill     ~> sledgehammer kill_atps
  1448     atp_messages ~> sledgehammer messages
  1449     atp_minimize ~> sledgehammer minimize
  1450     print_atps   ~> sledgehammer available_atps
  1451     INCOMPATIBILITY.
  1452   - Added user's manual ("isabelle doc sledgehammer").
  1453   - Added option syntax and "sledgehammer_params" to customize
  1454     Sledgehammer's behavior.  See the manual for details.
  1455   - Modified the Isar proof reconstruction code so that it produces
  1456     direct proofs rather than proofs by contradiction.  (This feature
  1457     is still experimental.)
  1458   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1459     full-typed mode.
  1460   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1461 
  1462 * Nitpick:
  1463   - Added and implemented "binary_ints" and "bits" options.
  1464   - Added "std" option and implemented support for nonstandard models.
  1465   - Added and implemented "finitize" option to improve the precision
  1466     of infinite datatypes based on a monotonicity analysis.
  1467   - Added support for quotient types.
  1468   - Added support for "specification" and "ax_specification"
  1469     constructs.
  1470   - Added support for local definitions (for "function" and
  1471     "termination" proofs).
  1472   - Added support for term postprocessors.
  1473   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1474   - Improved efficiency of "destroy_constrs" optimization.
  1475   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1476     record getters.
  1477   - Fixed soundness bug related to higher-order constructors.
  1478   - Fixed soundness bug when "full_descrs" is enabled.
  1479   - Improved precision of set constructs.
  1480   - Added "atoms" option.
  1481   - Added cache to speed up repeated Kodkod invocations on the same
  1482     problems.
  1483   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1484     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1485     "SAT4J_Light".  INCOMPATIBILITY.
  1486   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1487     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1488   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1489 
  1490 * Method "induct" now takes instantiations of the form t, where t is not
  1491   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1492   If this is not intended, t has to be enclosed in parentheses.
  1493   By default, the equalities generated by definitional instantiations
  1494   are pre-simplified, which may cause parameters of inductive cases
  1495   to disappear, or may even delete some of the inductive cases.
  1496   Use "induct (no_simp)" instead of "induct" to restore the old
  1497   behaviour. The (no_simp) option is also understood by the "cases"
  1498   and "nominal_induct" methods, which now perform pre-simplification, too.
  1499   INCOMPATIBILITY.
  1500 
  1501 
  1502 *** HOLCF ***
  1503 
  1504 * Variable names in lemmas generated by the domain package have
  1505 changed; the naming scheme is now consistent with the HOL datatype
  1506 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1507 
  1508 * The domain package no longer defines the function "foo_copy" for
  1509 recursive domain "foo".  The reach lemma is now stated directly in
  1510 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1511 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1512 
  1513 * Most definedness lemmas generated by the domain package (previously
  1514 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1515 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1516 Proofs that used definedness lemmas as intro rules may break,
  1517 potential INCOMPATIBILITY.
  1518 
  1519 * Induction and casedist rules generated by the domain package now
  1520 declare proper case_names (one called "bottom", and one named for each
  1521 constructor).  INCOMPATIBILITY.
  1522 
  1523 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1524 rules are generated for each domain, INCOMPATIBILITY.
  1525 
  1526   foo_bar.reach       ~> foo.reach  bar.reach
  1527   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1528 
  1529 * Some lemmas generated by the domain package have been renamed for
  1530 consistency with the datatype package, INCOMPATIBILITY.
  1531 
  1532   foo.ind        ~> foo.induct
  1533   foo.finite_ind ~> foo.finite_induct
  1534   foo.coind      ~> foo.coinduct
  1535   foo.casedist   ~> foo.exhaust
  1536   foo.exhaust    ~> foo.nchotomy
  1537 
  1538 * For consistency with other definition packages, the fixrec package
  1539 now generates qualified theorem names, INCOMPATIBILITY.
  1540 
  1541   foo_simps  ~> foo.simps
  1542   foo_unfold ~> foo.unfold
  1543   foo_induct ~> foo.induct
  1544 
  1545 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1546 method and internal fixrec proofs now use the default simpset instead.
  1547 INCOMPATIBILITY.
  1548 
  1549 * The "contlub" predicate has been removed.  Proof scripts should use
  1550 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1551 
  1552 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1553 
  1554 * The constants cpair, cfst, and csnd have been removed in favor of
  1555 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1556 
  1557 
  1558 *** ML ***
  1559 
  1560 * Antiquotations for basic formal entities:
  1561 
  1562     @{class NAME}         -- type class
  1563     @{class_syntax NAME}  -- syntax representation of the above
  1564 
  1565     @{type_name NAME}     -- logical type
  1566     @{type_abbrev NAME}   -- type abbreviation
  1567     @{nonterminal NAME}   -- type of concrete syntactic category
  1568     @{type_syntax NAME}   -- syntax representation of any of the above
  1569 
  1570     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1571     @{const_abbrev NAME}  -- abbreviated constant
  1572     @{const_syntax NAME}  -- syntax representation of any of the above
  1573 
  1574 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1575 syntax constant (cf. 'syntax' command).
  1576 
  1577 * Antiquotation @{make_string} inlines a function to print arbitrary
  1578 values similar to the ML toplevel.  The result is compiler dependent
  1579 and may fall back on "?" in certain situations.
  1580 
  1581 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1582 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1583 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1584 not work with the asynchronous Isar document model.
  1585 
  1586 * Configuration options now admit dynamic default values, depending on
  1587 the context or even global references.
  1588 
  1589 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1590 uses an efficient external library if available (for Poly/ML).
  1591 
  1592 * Renamed some important ML structures, while keeping the old names
  1593 for some time as aliases within the structure Legacy:
  1594 
  1595   OuterKeyword  ~>  Keyword
  1596   OuterLex      ~>  Token
  1597   OuterParse    ~>  Parse
  1598   OuterSyntax   ~>  Outer_Syntax
  1599   PrintMode     ~>  Print_Mode
  1600   SpecParse     ~>  Parse_Spec
  1601   ThyInfo       ~>  Thy_Info
  1602   ThyLoad       ~>  Thy_Load
  1603   ThyOutput     ~>  Thy_Output
  1604   TypeInfer     ~>  Type_Infer
  1605 
  1606 Note that "open Legacy" simplifies porting of sources, but forgetting
  1607 to remove it again will complicate porting again in the future.
  1608 
  1609 * Most operations that refer to a global context are named
  1610 accordingly, e.g. Simplifier.global_context or
  1611 ProofContext.init_global.  There are some situations where a global
  1612 context actually works, but under normal circumstances one needs to
  1613 pass the proper local context through the code!
  1614 
  1615 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1616 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1617 Pretty.pp argument to merge, which is absent in the standard
  1618 Theory_Data version.
  1619 
  1620 * Sorts.certify_sort and derived "cert" operations for types and terms
  1621 no longer minimize sorts.  Thus certification at the boundary of the
  1622 inference kernel becomes invariant under addition of class relations,
  1623 which is an important monotonicity principle.  Sorts are now minimized
  1624 in the syntax layer only, at the boundary between the end-user and the
  1625 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1626 explicitly in rare situations.
  1627 
  1628 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1629 emphasize that this is in no way a standard operation.
  1630 INCOMPATIBILITY.
  1631 
  1632 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1633 usual for resolution.  Rare INCOMPATIBILITY.
  1634 
  1635 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1636 to emphasize that these only work in a global situation (which is
  1637 quite rare).
  1638 
  1639 * Curried take and drop in library.ML; negative length is interpreted
  1640 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1641 
  1642 * Proof terms: type substitutions on proof constants now use canonical
  1643 order of type variables.  INCOMPATIBILITY for tools working with proof
  1644 terms.
  1645 
  1646 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1647 may no longer carry premises.  User-level specifications are
  1648 transformed accordingly by Thm.add_axiom/add_def.
  1649 
  1650 
  1651 *** System ***
  1652 
  1653 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1654 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1655 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1656 
  1657 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1658 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1659 respectively.
  1660 
  1661 * Old lib/scripts/polyml-platform is superseded by the
  1662 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1663 variant, even on a 64 bit machine.  The following example setting
  1664 prefers 64 bit if available:
  1665 
  1666   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1667 
  1668 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1669 Isabelle/Scala layer for advanced prover interaction and integration.
  1670 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1671 component.
  1672 
  1673 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1674 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1675 similar to the default assignment of the document preparation system
  1676 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1677 provides some operations for direct access to the font without asking
  1678 the user for manual installation.
  1679 
  1680 
  1681 
  1682 New in Isabelle2009-1 (December 2009)
  1683 -------------------------------------
  1684 
  1685 *** General ***
  1686 
  1687 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1688 one backslash should be used, even in ML sources.
  1689 
  1690 
  1691 *** Pure ***
  1692 
  1693 * Locale interpretation propagates mixins along the locale hierarchy.
  1694 The currently only available mixins are the equations used to map
  1695 local definitions to terms of the target domain of an interpretation.
  1696 
  1697 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1698 loc" to print all interpretations of locale "loc" in the theory.
  1699 Interpretations in proofs are not shown.
  1700 
  1701 * Thoroughly revised locales tutorial.  New section on conditional
  1702 interpretation.
  1703 
  1704 * On instantiation of classes, remaining undefined class parameters
  1705 are formally declared.  INCOMPATIBILITY.
  1706 
  1707 
  1708 *** Document preparation ***
  1709 
  1710 * New generalized style concept for printing terms: @{foo (style) ...}
  1711 instead of @{foo_style style ...}  (old form is still retained for
  1712 backward compatibility).  Styles can be also applied for
  1713 antiquotations prop, term_type and typeof.
  1714 
  1715 
  1716 *** HOL ***
  1717 
  1718 * New proof method "smt" for a combination of first-order logic with
  1719 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1720 fixed-size bitvectors; there is also basic support for higher-order
  1721 features (esp. lambda abstractions).  It is an incomplete decision
  1722 procedure based on external SMT solvers using the oracle mechanism;
  1723 for the SMT solver Z3, this method is proof-producing.  Certificates
  1724 are provided to avoid calling the external solvers solely for
  1725 re-checking proofs.  Due to a remote SMT service there is no need for
  1726 installing SMT solvers locally.  See src/HOL/SMT.
  1727 
  1728 * New commands to load and prove verification conditions generated by
  1729 the Boogie program verifier or derived systems (e.g. the Verifying C
  1730 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1731 
  1732 * New counterexample generator tool 'nitpick' based on the Kodkod
  1733 relational model finder.  See src/HOL/Tools/Nitpick and
  1734 src/HOL/Nitpick_Examples.
  1735 
  1736 * New commands 'code_pred' and 'values' to invoke the predicate
  1737 compiler and to enumerate values of inductive predicates.
  1738 
  1739 * A tabled implementation of the reflexive transitive closure.
  1740 
  1741 * New implementation of quickcheck uses generic code generator;
  1742 default generators are provided for all suitable HOL types, records
  1743 and datatypes.  Old quickcheck can be re-activated importing theory
  1744 Library/SML_Quickcheck.
  1745 
  1746 * New testing tool Mirabelle for automated proof tools.  Applies
  1747 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1748 every proof step in a theory.  To be used in batch mode via the
  1749 "mirabelle" utility.
  1750 
  1751 * New proof method "sos" (sum of squares) for nonlinear real
  1752 arithmetic (originally due to John Harison). It requires theory
  1753 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1754 works well in practice on quantifier-free real arithmetic with +, -,
  1755 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1756 inequalities between polynomials.  It makes use of external
  1757 semidefinite programming solvers.  Method "sos" generates a
  1758 certificate that can be pasted into the proof thus avoiding the need
  1759 to call an external tool every time the proof is checked.  See
  1760 src/HOL/Library/Sum_Of_Squares.
  1761 
  1762 * New method "linarith" invokes existing linear arithmetic decision
  1763 procedure only.
  1764 
  1765 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1766 
  1767 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1768 Causes full type information to be output to the ATPs.  This slows
  1769 ATPs down considerably but eliminates a source of unsound "proofs"
  1770 that fail later.
  1771 
  1772 * New method "metisFT": A version of metis that uses full type
  1773 information in order to avoid failures of proof reconstruction.
  1774 
  1775 * New evaluator "approximate" approximates an real valued term using
  1776 the same method as the approximation method.
  1777 
  1778 * Method "approximate" now supports arithmetic expressions as
  1779 boundaries of intervals and implements interval splitting and Taylor
  1780 series expansion.
  1781 
  1782 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1783 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1784 
  1785 * New theory SupInf of the supremum and infimum operators for sets of
  1786 reals.
  1787 
  1788 * New theory Probability, which contains a development of measure
  1789 theory, eventually leading to Lebesgue integration and probability.
  1790 
  1791 * Extended Multivariate Analysis to include derivation and Brouwer's
  1792 fixpoint theorem.
  1793 
  1794 * Reorganization of number theory, INCOMPATIBILITY:
  1795   - new number theory development for nat and int, in theories Divides
  1796     and GCD as well as in new session Number_Theory
  1797   - some constants and facts now suffixed with _nat and _int
  1798     accordingly
  1799   - former session NumberTheory now named Old_Number_Theory, including
  1800     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1801   - moved theory Pocklington from src/HOL/Library to
  1802     src/HOL/Old_Number_Theory
  1803 
  1804 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1805 lcm of finite and infinite sets. It is shown that they form a complete
  1806 lattice.
  1807 
  1808 * Class semiring_div requires superclass no_zero_divisors and proof of
  1809 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1810 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1811 generalized to class semiring_div, subsuming former theorems
  1812 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1813 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1814 INCOMPATIBILITY.
  1815 
  1816 * Refinements to lattice classes and sets:
  1817   - less default intro/elim rules in locale variant, more default
  1818     intro/elim rules in class variant: more uniformity
  1819   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1820     le_inf_iff
  1821   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1822     sup_aci)
  1823   - renamed ACI to inf_sup_aci
  1824   - new class "boolean_algebra"
  1825   - class "complete_lattice" moved to separate theory
  1826     "Complete_Lattice"; corresponding constants (and abbreviations)
  1827     renamed and with authentic syntax:
  1828     Set.Inf ~>    Complete_Lattice.Inf
  1829     Set.Sup ~>    Complete_Lattice.Sup
  1830     Set.INFI ~>   Complete_Lattice.INFI
  1831     Set.SUPR ~>   Complete_Lattice.SUPR
  1832     Set.Inter ~>  Complete_Lattice.Inter
  1833     Set.Union ~>  Complete_Lattice.Union
  1834     Set.INTER ~>  Complete_Lattice.INTER
  1835     Set.UNION ~>  Complete_Lattice.UNION
  1836   - authentic syntax for
  1837     Set.Pow
  1838     Set.image
  1839   - mere abbreviations:
  1840     Set.empty               (for bot)
  1841     Set.UNIV                (for top)
  1842     Set.inter               (for inf, formerly Set.Int)
  1843     Set.union               (for sup, formerly Set.Un)
  1844     Complete_Lattice.Inter  (for Inf)
  1845     Complete_Lattice.Union  (for Sup)
  1846     Complete_Lattice.INTER  (for INFI)
  1847     Complete_Lattice.UNION  (for SUPR)
  1848   - object-logic definitions as far as appropriate
  1849 
  1850 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1851 Un_subset_iff are explicitly deleted as default simp rules; then also
  1852 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1853 deleted to achieve the desired effect.
  1854 
  1855 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1856 rules by default any longer; the same applies to min_max.inf_absorb1
  1857 etc.  INCOMPATIBILITY.
  1858 
  1859 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1860 pred_set_conv by default.  INCOMPATIBILITY.
  1861 
  1862 * Power operations on relations and functions are now one dedicated
  1863 constant "compow" with infix syntax "^^".  Power operation on
  1864 multiplicative monoids retains syntax "^" and is now defined generic
  1865 in class power.  INCOMPATIBILITY.
  1866 
  1867 * Relation composition "R O S" now has a more standard argument order:
  1868 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1869 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1870 break, since the O_assoc rule was not rewritten like this.  Fix using
  1871 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1872 
  1873 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1874 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1875 INCOMPATIBILITY.
  1876 
  1877 * Most rules produced by inductive and datatype package have mandatory
  1878 prefixes.  INCOMPATIBILITY.
  1879 
  1880 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1881 the attribute of the same name.  Each of the theorems in the list
  1882 DERIV_intros assumes composition with an additional function and
  1883 matches a variable to the derivative, which has to be solved by the
  1884 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1885 of most elementary terms.  Former Maclauren.DERIV_tac and
  1886 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1887 INCOMPATIBILITY.
  1888 
  1889 * Code generator attributes follow the usual underscore convention:
  1890     code_unfold     replaces    code unfold
  1891     code_post       replaces    code post
  1892     etc.
  1893   INCOMPATIBILITY.
  1894 
  1895 * Renamed methods:
  1896     sizechange -> size_change
  1897     induct_scheme -> induction_schema
  1898   INCOMPATIBILITY.
  1899 
  1900 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1901 INCOMPATIBILITY, use "undefined" directly.
  1902 
  1903 * Renamed theorems:
  1904     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1905     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1906     Suc_plus1 -> Suc_eq_plus1
  1907     *anti_sym -> *antisym*
  1908     vector_less_eq_def -> vector_le_def
  1909   INCOMPATIBILITY.
  1910 
  1911 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1912 INCOMPATIBILITY.
  1913 
  1914 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1915 INCOMPATIBILITY.
  1916 
  1917 
  1918 *** HOLCF ***
  1919 
  1920 * Theory Representable defines a class "rep" of domains that are
  1921 representable (via an ep-pair) in the universal domain type "udom".
  1922 Instances are provided for all type constructors defined in HOLCF.
  1923 
  1924 * The 'new_domain' command is a purely definitional version of the
  1925 domain package, for representable domains.  Syntax is identical to the
  1926 old domain package.  The 'new_domain' package also supports indirect
  1927 recursion using previously-defined type constructors.  See
  1928 src/HOLCF/ex/New_Domain.thy for examples.
  1929 
  1930 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1931 on the left-hand side of an equation, and then performs
  1932 simplification.  Rewriting is done using rules declared with the
  1933 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1934 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1935 
  1936 * The pattern-match compiler in 'fixrec' can now handle constructors
  1937 with HOL function types.  Pattern-match combinators for the Pair
  1938 constructor are pre-configured.
  1939 
  1940 * The 'fixrec' package now produces better fixed-point induction rules
  1941 for mutually-recursive definitions:  Induction rules have conclusions
  1942 of the form "P foo bar" instead of "P <foo, bar>".
  1943 
  1944 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1945 been renamed to "below".  The name "below" now replaces "less" in many
  1946 theorem names.  (Legacy theorem names using "less" are still supported
  1947 as well.)
  1948 
  1949 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1950 patterns can be used to generate strictness rules, or to make
  1951 functions more strict (much like the bang-patterns supported by the
  1952 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1953 examples.
  1954 
  1955 
  1956 *** ML ***
  1957 
  1958 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1959 errors and run-time exceptions, including detailed source positions.
  1960 
  1961 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1962 identified entries, with some additional information such as source
  1963 position, logical grouping etc.
  1964 
  1965 * Theory and context data is now introduced by the simplified and
  1966 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1967 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1968 copy operation) is still available for some time.
  1969 
  1970 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1971 provides a high-level programming interface to synchronized state
  1972 variables with atomic update.  This works via pure function
  1973 application within a critical section -- its runtime should be as
  1974 short as possible; beware of deadlocks if critical code is nested,
  1975 either directly or indirectly via other synchronized variables!
  1976 
  1977 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1978 wraps raw ML references, explicitly indicating their non-thread-safe
  1979 behaviour.  The Isar toplevel keeps this structure open, to
  1980 accommodate Proof General as well as quick and dirty interactive
  1981 experiments with references.
  1982 
  1983 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1984 parallel tactical reasoning.
  1985 
  1986 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1987 are similar to SUBPROOF, but are slightly more flexible: only the
  1988 specified parts of the subgoal are imported into the context, and the
  1989 body tactic may introduce new subgoals and schematic variables.
  1990 
  1991 * Old tactical METAHYPS, which does not observe the proof context, has
  1992 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1993 or Subgoal.FOCUS etc.
  1994 
  1995 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1996 functors have their own ML name space there is no point to mark them
  1997 separately.)  Minor INCOMPATIBILITY.
  1998 
  1999 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  2000 
  2001 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  2002 INCOMPATIBILITY.
  2003 
  2004 * Operations of structure Skip_Proof no longer require quick_and_dirty
  2005 mode, which avoids critical setmp.
  2006 
  2007 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  2008 combinators for "args".  INCOMPATIBILITY, need to use simplified
  2009 Attrib/Method.setup introduced in Isabelle2009.
  2010 
  2011 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  2012 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  2013 last resort.  INCOMPATIBILITY.
  2014 
  2015 * Display.pretty_thm now requires a proper context (cf. former
  2016 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  2017 or even Display.pretty_thm_without_context as last resort.
  2018 INCOMPATIBILITY.
  2019 
  2020 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  2021 Syntax.pretty_typ/term directly, preferably with proper context
  2022 instead of global theory.
  2023 
  2024 
  2025 *** System ***
  2026 
  2027 * Further fine tuning of parallel proof checking, scales up to 8 cores
  2028 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  2029 usedir option -q.
  2030 
  2031 * Support for additional "Isabelle components" via etc/components, see
  2032 also the system manual.
  2033 
  2034 * The isabelle makeall tool now operates on all components with
  2035 IsaMakefile, not just hardwired "logics".
  2036 
  2037 * Removed "compress" option from isabelle-process and isabelle usedir;
  2038 this is always enabled.
  2039 
  2040 * Discontinued support for Poly/ML 4.x versions.
  2041 
  2042 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  2043 on a given logic image.  This requires the lighttpd webserver and is
  2044 currently supported on Linux only.
  2045 
  2046 
  2047 
  2048 New in Isabelle2009 (April 2009)
  2049 --------------------------------
  2050 
  2051 *** General ***
  2052 
  2053 * Simplified main Isabelle executables, with less surprises on
  2054 case-insensitive file-systems (such as Mac OS).
  2055 
  2056   - The main Isabelle tool wrapper is now called "isabelle" instead of
  2057     "isatool."
  2058 
  2059   - The former "isabelle" alias for "isabelle-process" has been
  2060     removed (should rarely occur to regular users).
  2061 
  2062   - The former "isabelle-interface" and its alias "Isabelle" have been
  2063     removed (interfaces are now regular Isabelle tools).
  2064 
  2065 Within scripts and make files, the Isabelle environment variables
  2066 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  2067 respectively.  (The latter are still available as legacy feature.)
  2068 
  2069 The old isabelle-interface wrapper could react in confusing ways if
  2070 the interface was uninstalled or changed otherwise.  Individual
  2071 interface tool configuration is now more explicit, see also the
  2072 Isabelle system manual.  In particular, Proof General is now available
  2073 via "isabelle emacs".
  2074 
  2075 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  2076 purge installed copies of Isabelle executables and re-run "isabelle
  2077 install -p ...", or use symlinks.
  2078 
  2079 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  2080 old ~/isabelle, which was slightly non-standard and apt to cause
  2081 surprises on case-insensitive file-systems (such as Mac OS).
  2082 
  2083 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  2084 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  2085 care is required when using older releases of Isabelle.  Note that
  2086 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  2087 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  2088 
  2089 * Proofs of fully specified statements are run in parallel on
  2090 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  2091 a regular 4-core machine, if the initial heap space is made reasonably
  2092 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  2093 
  2094 * The main reference manuals ("isar-ref", "implementation", and
  2095 "system") have been updated and extended.  Formally checked references
  2096 as hyperlinks are now available uniformly.
  2097 
  2098 
  2099 *** Pure ***
  2100 
  2101 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  2102 respects.  The most important changes are listed below.  See the
  2103 Tutorial on Locales ("locales" manual) for details.
  2104 
  2105 - In locale expressions, instantiation replaces renaming.  Parameters
  2106 must be declared in a for clause.  To aid compatibility with previous
  2107 parameter inheritance, in locale declarations, parameters that are not
  2108 'touched' (instantiation position "_" or omitted) are implicitly added
  2109 with their syntax at the beginning of the for clause.
  2110 
  2111 - Syntax from abbreviations and definitions in locales is available in
  2112 locale expressions and context elements.  The latter is particularly
  2113 useful in locale declarations.
  2114 
  2115 - More flexible mechanisms to qualify names generated by locale
  2116 expressions.  Qualifiers (prefixes) may be specified in locale
  2117 expressions, and can be marked as mandatory (syntax: "name!:") or
  2118 optional (syntax "name?:").  The default depends for plain "name:"
  2119 depends on the situation where a locale expression is used: in
  2120 commands 'locale' and 'sublocale' prefixes are optional, in
  2121 'interpretation' and 'interpret' prefixes are mandatory.  The old
  2122 implicit qualifiers derived from the parameter names of a locale are
  2123 no longer generated.
  2124 
  2125 - Command "sublocale l < e" replaces "interpretation l < e".  The
  2126 instantiation clause in "interpretation" and "interpret" (square
  2127 brackets) is no longer available.  Use locale expressions.
  2128 
  2129 - When converting proof scripts, mandatory qualifiers in
  2130 'interpretation' and 'interpret' should be retained by default, even
  2131 if this is an INCOMPATIBILITY compared to former behavior.  In the
  2132 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  2133 in locale expressions range over a single locale instance only.
  2134 
  2135 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  2136 In existing theorem specifications replace the includes element by the
  2137 respective context elements of the included locale, omitting those
  2138 that are already present in the theorem specification.  Multiple
  2139 assume elements of a locale should be replaced by a single one
  2140 involving the locale predicate.  In the proof body, declarations (most
  2141 notably theorems) may be regained by interpreting the respective
  2142 locales in the proof context as required (command "interpret").
  2143 
  2144 If using "includes" in replacement of a target solely because the
  2145 parameter types in the theorem are not as general as in the target,
  2146 consider declaring a new locale with additional type constraints on
  2147 the parameters (context element "constrains").
  2148 
  2149 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2150 
  2151 - Locale interpretation commands no longer attempt to simplify goal.
  2152 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2153 methods intro_locales and unfold_locales to clarify.
  2154 
  2155 - Locale interpretation commands no longer accept interpretation
  2156 attributes.  INCOMPATIBILITY.
  2157 
  2158 * Class declaration: so-called "base sort" must not be given in import
  2159 list any longer, but is inferred from the specification.  Particularly
  2160 in HOL, write
  2161 
  2162     class foo = ...
  2163 
  2164 instead of
  2165 
  2166     class foo = type + ...
  2167 
  2168 * Class target: global versions of theorems stemming do not carry a
  2169 parameter prefix any longer.  INCOMPATIBILITY.
  2170 
  2171 * Class 'instance' command no longer accepts attached definitions.
  2172 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2173 
  2174 * Recovered hiding of consts, which was accidentally broken in
  2175 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2176 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2177 
  2178 * Slightly more coherent Pure syntax, with updated documentation in
  2179 isar-ref manual.  Removed locales meta_term_syntax and
  2180 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2181 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2182 directly in regular applications.
  2183 
  2184 * There is a new syntactic category "float_const" for signed decimal
  2185 fractions (e.g. 123.45 or -123.45).
  2186 
  2187 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2188 interface with 'setup' command instead.
  2189 
  2190 * Command 'local_setup' is similar to 'setup', but operates on a local
  2191 theory context.
  2192 
  2193 * The 'axiomatization' command now only works within a global theory
  2194 context.  INCOMPATIBILITY.
  2195 
  2196 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2197 hypotheses.  Sorts required in the course of reasoning need to be
  2198 covered by the constraints in the initial statement, completed by the
  2199 type instance information of the background theory.  Non-trivial sort
  2200 hypotheses, which rarely occur in practice, may be specified via
  2201 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2202 
  2203   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2204 
  2205 The result contains an implicit sort hypotheses as before --
  2206 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2207 normalization.
  2208 
  2209 * Generalized Isar history, with support for linear undo, direct state
  2210 addressing etc.
  2211 
  2212 * Changed defaults for unify configuration options:
  2213 
  2214   unify_trace_bound = 50 (formerly 25)
  2215   unify_search_bound = 60 (formerly 30)
  2216 
  2217 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2218 
  2219   a) On theory merge, the last set of code equations for a particular
  2220      constant is taken (in accordance with the policy applied by other
  2221      parts of the code generator framework).
  2222 
  2223   b) Code equations stemming from explicit declarations (e.g. code
  2224      attribute) gain priority over default code equations stemming
  2225      from definition, primrec, fun etc.
  2226 
  2227 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2228 
  2229 * Unified theorem tables for both code generators.  Thus [code
  2230 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2231 
  2232 * Command 'find_consts' searches for constants based on type and name
  2233 patterns, e.g.
  2234 
  2235     find_consts "_ => bool"
  2236 
  2237 By default, matching is against subtypes, but it may be restricted to
  2238 the whole type.  Searching by name is possible.  Multiple queries are
  2239 conjunctive and queries may be negated by prefixing them with a
  2240 hyphen:
  2241 
  2242     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2243 
  2244 * New 'find_theorems' criterion "solves" matches theorems that
  2245 directly solve the current goal (modulo higher-order unification).
  2246 
  2247 * Auto solve feature for main theorem statements: whenever a new goal
  2248 is stated, "find_theorems solves" is called; any theorems that could
  2249 solve the lemma directly are listed as part of the goal state.
  2250 Cf. associated options in Proof General Isabelle settings menu,
  2251 enabled by default, with reasonable timeout for pathological cases of
  2252 higher-order unification.
  2253 
  2254 
  2255 *** Document preparation ***
  2256 
  2257 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2258 demanding keyword 'by' and supporting the full method expression
  2259 syntax just like the Isar command 'by'.
  2260 
  2261 
  2262 *** HOL ***
  2263 
  2264 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2265 points Main and Complex_Main remain as before.
  2266 
  2267 * Logic image HOL-Plain provides a minimal HOL with the most important
  2268 tools available (inductive, datatype, primrec, ...).  This facilitates
  2269 experimentation and tool development.  Note that user applications
  2270 (and library theories) should never refer to anything below theory
  2271 Main, as before.
  2272 
  2273 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2274 experimentation due to shorter build times.
  2275 
  2276 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2277 were previously part of former HOL-Complex.  Entry point Hyperreal
  2278 remains valid, but theories formerly using Complex_Main should now use
  2279 new entry point Hypercomplex.
  2280 
  2281 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2282 Posix processes.  Avoids potentially expensive forking of the ML
  2283 process.  New thread-based implementation also works on non-Unix
  2284 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2285 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2286 commands are covered in the isar-ref manual.
  2287 
  2288 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2289 sledgehammer without local ATP installation (Vampire etc.). Other
  2290 provers may be included via suitable ML wrappers, see also
  2291 src/HOL/ATP_Linkup.thy.
  2292 
  2293 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2294 menu.
  2295 
  2296 * The metis method no longer fails because the theorem is too trivial
  2297 (contains the empty clause).
  2298 
  2299 * The metis method now fails in the usual manner, rather than raising
  2300 an exception, if it determines that it cannot prove the theorem.
  2301 
  2302 * Method "coherent" implements a prover for coherent logic (see also
  2303 src/Tools/coherent.ML).
  2304 
  2305 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2306 "undefined" is the right choice to replace "arbitrary", though
  2307 logically there is no difference.  INCOMPATIBILITY.
  2308 
  2309 * Command "value" now integrates different evaluation mechanisms.  The
  2310 result of the first successful evaluation mechanism is printed.  In
  2311 square brackets a particular named evaluation mechanisms may be
  2312 specified (currently, [SML], [code] or [nbe]).  See further
  2313 src/HOL/ex/Eval_Examples.thy.
  2314 
  2315 * Normalization by evaluation now allows non-leftlinear equations.
  2316 Declare with attribute [code nbe].
  2317 
  2318 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2319 as the structured Isar versions "cases" and "induct", cf. the
  2320 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2321 are now presented as a list of individual projections
  2322 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2323 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2324 rare situations a different rule is selected --- notably nested tuple
  2325 elimination instead of former prod.exhaust: use explicit (case_tac t
  2326 rule: prod.exhaust) here.
  2327 
  2328 * Attributes "cases", "induct", "coinduct" support "del" option.
  2329 
  2330 * Removed fact "case_split_thm", which duplicates "case_split".
  2331 
  2332 * The option datatype has been moved to a new theory Option.  Renamed
  2333 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2334 
  2335 * New predicate "strict_mono" classifies strict functions on partial
  2336 orders.  With strict functions on linear orders, reasoning about
  2337 (in)equalities is facilitated by theorems "strict_mono_eq",
  2338 "strict_mono_less_eq" and "strict_mono_less".
  2339 
  2340 * Some set operations are now proper qualified constants with
  2341 authentic syntax.  INCOMPATIBILITY:
  2342 
  2343     op Int ~>   Set.Int
  2344     op Un ~>    Set.Un
  2345     INTER ~>    Set.INTER
  2346     UNION ~>    Set.UNION
  2347     Inter ~>    Set.Inter
  2348     Union ~>    Set.Union
  2349     {} ~>       Set.empty
  2350     UNIV ~>     Set.UNIV
  2351 
  2352 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2353 theory Set.
  2354 
  2355 * Auxiliary class "itself" has disappeared -- classes without any
  2356 parameter are treated as expected by the 'class' command.
  2357 
  2358 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2359 
  2360 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2361 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2362 
  2363 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2364 method "approximation".  It proves formulas on real values by using
  2365 interval arithmetic.  In the formulas are also the transcendental
  2366 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2367 allowed. For examples see
  2368 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2369 
  2370 * Theory "Reflection" now resides in HOL/Library.
  2371 
  2372 * Entry point to Word library now simply named "Word".
  2373 INCOMPATIBILITY.
  2374 
  2375 * Made source layout more coherent with logical distribution
  2376 structure:
  2377 
  2378     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2379     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2380     src/HOL/Library/GCD.thy ~> src/HOL/
  2381     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2382     src/HOL/Library/Parity.thy ~> src/HOL/
  2383     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2384     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2385     src/HOL/Real/Lubs.thy ~> src/HOL/
  2386     src/HOL/Real/PReal.thy ~> src/HOL/
  2387     src/HOL/Real/Rational.thy ~> src/HOL/
  2388     src/HOL/Real/RComplete.thy ~> src/HOL/
  2389     src/HOL/Real/RealDef.thy ~> src/HOL/
  2390     src/HOL/Real/RealPow.thy ~> src/HOL/
  2391     src/HOL/Real/Real.thy ~> src/HOL/
  2392     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2393     src/HOL/Complex/Complex.thy ~> src/HOL/
  2394     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2395     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2396     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2397     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2398     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2399     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2400     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2401     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2402     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2403     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2404     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2405     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2406     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2407     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2408     src/HOL/Real/Float ~> src/HOL/Library/
  2409     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2410     src/HOL/Real/RealVector.thy ~> src/HOL/
  2411 
  2412     src/HOL/arith_data.ML ~> src/HOL/Tools
  2413     src/HOL/hologic.ML ~> src/HOL/Tools
  2414     src/HOL/simpdata.ML ~> src/HOL/Tools
  2415     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2416     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2417     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2418     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2419     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2420     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2421     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2422 
  2423     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2424     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2425     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2426     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2427     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2428     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2429 
  2430 * If methods "eval" and "evaluation" encounter a structured proof
  2431 state with !!/==>, only the conclusion is evaluated to True (if
  2432 possible), avoiding strange error messages.
  2433 
  2434 * Method "sizechange" automates termination proofs using (a
  2435 modification of) the size-change principle.  Requires SAT solver.  See
  2436 src/HOL/ex/Termination.thy for examples.
  2437 
  2438 * Simplifier: simproc for let expressions now unfolds if bound
  2439 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2440 
  2441 * Method "arith": Linear arithmetic now ignores all inequalities when
  2442 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2443 
  2444 * New attribute "arith" for facts that should always be used
  2445 automatically by arithmetic. It is intended to be used locally in
  2446 proofs, e.g.
  2447 
  2448   assumes [arith]: "x > 0"
  2449 
  2450 Global usage is discouraged because of possible performance impact.
  2451 
  2452 * New classes "top" and "bot" with corresponding operations "top" and
  2453 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2454 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2455 
  2456 * Changed definition lemma "less_fun_def" in order to provide an
  2457 instance for preorders on functions; use lemma "less_le" instead.
  2458 INCOMPATIBILITY.
  2459 
  2460 * Theory Orderings: class "wellorder" moved here, with explicit
  2461 induction rule "less_induct" as assumption.  For instantiation of
  2462 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2463 INCOMPATIBILITY.
  2464 
  2465 * Theory Orderings: added class "preorder" as superclass of "order".
  2466 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2467 etc. slightly changed.  Some theorems named order_class.* now named
  2468 preorder_class.*.
  2469 
  2470 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2471 "diag" to "Id_on".
  2472 
  2473 * Theory Finite_Set: added a new fold combinator of type
  2474 
  2475   ('a => 'b => 'b) => 'b => 'a set => 'b
  2476 
  2477 Occasionally this is more convenient than the old fold combinator
  2478 which is now defined in terms of the new one and renamed to
  2479 fold_image.
  2480 
  2481 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2482 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2483 extended with further lemmas!).  At the moment both still exist but
  2484 the former will disappear at some point.
  2485 
  2486 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2487 class recpower.  Type-specific simp rules for various recpower types
  2488 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2489 
  2490 rat_power_0    -> power_0
  2491 rat_power_Suc  -> power_Suc
  2492 realpow_0      -> power_0
  2493 realpow_Suc    -> power_Suc
  2494 complexpow_0   -> power_0
  2495 complexpow_Suc -> power_Suc
  2496 power_poly_0   -> power_0
  2497 power_poly_Suc -> power_Suc
  2498 
  2499 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2500 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2501 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2502 of lemmas from Divides has been generalized from nat to class
  2503 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2504 renames resulting from duplicate elimination:
  2505 
  2506     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2507     zero_dvd_iff ~>         dvd_0_left_iff
  2508     dvd_0 ~>                dvd_0_right
  2509     DIVISION_BY_ZERO_DIV ~> div_by_0
  2510     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2511     mult_div ~>             div_mult_self2_is_id
  2512     mult_mod ~>             mod_mult_self2_is_0
  2513 
  2514 * Theory IntDiv: removed many lemmas that are instances of class-based
  2515 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2516 rename old lemmas as follows:
  2517 
  2518 dvd_diff               -> nat_dvd_diff
  2519 dvd_zminus_iff         -> dvd_minus_iff
  2520 mod_add1_eq            -> mod_add_eq
  2521 mod_mult1_eq           -> mod_mult_right_eq
  2522 mod_mult1_eq'          -> mod_mult_left_eq
  2523 mod_mult_distrib_mod   -> mod_mult_eq
  2524 nat_mod_add_left_eq    -> mod_add_left_eq
  2525 nat_mod_add_right_eq   -> mod_add_right_eq
  2526 nat_mod_div_trivial    -> mod_div_trivial
  2527 nat_mod_mod_trivial    -> mod_mod_trivial
  2528 zdiv_zadd_self1        -> div_add_self1
  2529 zdiv_zadd_self2        -> div_add_self2
  2530 zdiv_zmult_self1       -> div_mult_self2_is_id
  2531 zdiv_zmult_self2       -> div_mult_self1_is_id
  2532 zdvd_triv_left         -> dvd_triv_left
  2533 zdvd_triv_right        -> dvd_triv_right
  2534 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2535 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2536 zmod_zadd_left_eq      -> mod_add_left_eq
  2537 zmod_zadd_right_eq     -> mod_add_right_eq
  2538 zmod_zadd_self1        -> mod_add_self1
  2539 zmod_zadd_self2        -> mod_add_self2
  2540 zmod_zadd1_eq          -> mod_add_eq
  2541 zmod_zdiff1_eq         -> mod_diff_eq
  2542 zmod_zdvd_zmod         -> mod_mod_cancel
  2543 zmod_zmod_cancel       -> mod_mod_cancel
  2544 zmod_zmult_self1       -> mod_mult_self2_is_0
  2545 zmod_zmult_self2       -> mod_mult_self1_is_0
  2546 zmod_1                 -> mod_by_1
  2547 zdiv_1                 -> div_by_1
  2548 zdvd_abs1              -> abs_dvd_iff
  2549 zdvd_abs2              -> dvd_abs_iff
  2550 zdvd_refl              -> dvd_refl
  2551 zdvd_trans             -> dvd_trans
  2552 zdvd_zadd              -> dvd_add
  2553 zdvd_zdiff             -> dvd_diff
  2554 zdvd_zminus_iff        -> dvd_minus_iff
  2555 zdvd_zminus2_iff       -> minus_dvd_iff
  2556 zdvd_zmultD            -> dvd_mult_right
  2557 zdvd_zmultD2           -> dvd_mult_left
  2558 zdvd_zmult_mono        -> mult_dvd_mono
  2559 zdvd_0_right           -> dvd_0_right
  2560 zdvd_0_left            -> dvd_0_left_iff
  2561 zdvd_1_left            -> one_dvd
  2562 zminus_dvd_iff         -> minus_dvd_iff
  2563 
  2564 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2565 
  2566 * The real numbers offer decimal input syntax: 12.34 is translated
  2567 into 1234/10^2. This translation is not reversed upon output.
  2568 
  2569 * Theory Library/Polynomial defines an abstract type 'a poly of
  2570 univariate polynomials with coefficients of type 'a.  In addition to
  2571 the standard ring operations, it also supports div and mod.  Code
  2572 generation is also supported, using list-style constructors.
  2573 
  2574 * Theory Library/Inner_Product defines a class of real_inner for real
  2575 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2576 => real.  Class real_inner is a subclass of real_normed_vector from
  2577 theory RealVector.
  2578 
  2579 * Theory Library/Product_Vector provides instances for the product
  2580 type 'a * 'b of several classes from RealVector and Inner_Product.
  2581 Definitions of addition, subtraction, scalar multiplication, norms,
  2582 and inner products are included.
  2583 
  2584 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2585 addition to the field operations, numerals and case syntax are also
  2586 supported.
  2587 
  2588 * Theory Library/Diagonalize provides constructive version of Cantor's
  2589 first diagonalization argument.
  2590 
  2591 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2592 zlcm (for int); carried together from various gcd/lcm developements in
  2593 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2594 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2595 may recover tupled syntax as follows:
  2596 
  2597     hide (open) const gcd
  2598     abbreviation gcd where
  2599       "gcd == (%(a, b). GCD.gcd a b)"
  2600     notation (output)
  2601       GCD.gcd ("gcd '(_, _')")
  2602 
  2603 The same works for lcm, zgcd, zlcm.
  2604 
  2605 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2606 instantiations for algebraic structures.  Removed some duplicate
  2607 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2608 
  2609 * ML antiquotation @{code} takes a constant as argument and generates
  2610 corresponding code in background and inserts name of the corresponding
  2611 resulting ML value/function/datatype constructor binding in place.
  2612 All occurrences of @{code} with a single ML block are generated
  2613 simultaneously.  Provides a generic and safe interface for
  2614 instrumentalizing code generation.  See
  2615 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2616 In future you ought to refrain from ad-hoc compiling generated SML
  2617 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2618 cannot refer to constants for which user-defined serializations are
  2619 set.  Refer to the corresponding ML counterpart directly in that
  2620 cases.
  2621 
  2622 * Command 'rep_datatype': instead of theorem names the command now
  2623 takes a list of terms denoting the constructors of the type to be
  2624 represented as datatype.  The characteristic theorems have to be
  2625 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2626 have disappeared in favour of existing ones:
  2627 
  2628     unit_induct                 ~> unit.induct
  2629     prod_induct                 ~> prod.induct
  2630     sum_induct                  ~> sum.induct
  2631     Suc_Suc_eq                  ~> nat.inject
  2632     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2633 
  2634 
  2635 *** HOL-Algebra ***
  2636 
  2637 * New locales for orders and lattices where the equivalence relation
  2638 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2639 locales use a record structure with field eq for the equivalence.
  2640 
  2641 * New theory of factorial domains.
  2642 
  2643 * Units_l_inv and Units_r_inv are now simp rules by default.
  2644 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2645 and/or r_inv will now also require deletion of these lemmas.
  2646 
  2647 * Renamed the following theorems, INCOMPATIBILITY:
  2648 
  2649 UpperD ~> Upper_memD
  2650 LowerD ~> Lower_memD
  2651 least_carrier ~> least_closed
  2652 greatest_carrier ~> greatest_closed
  2653 greatest_Lower_above ~> greatest_Lower_below
  2654 one_zero ~> carrier_one_zero
  2655 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2656 
  2657 
  2658 *** HOL-Nominal ***
  2659 
  2660 * Nominal datatypes can now contain type-variables.
  2661 
  2662 * Commands 'nominal_inductive' and 'equivariance' work with local
  2663 theory targets.
  2664 
  2665 * Nominal primrec can now works with local theory targets and its
  2666 specification syntax now conforms to the general format as seen in
  2667 'inductive' etc.
  2668 
  2669 * Method "perm_simp" honours the standard simplifier attributes
  2670 (no_asm), (no_asm_use) etc.
  2671 
  2672 * The new predicate #* is defined like freshness, except that on the
  2673 left hand side can be a set or list of atoms.
  2674 
  2675 * Experimental command 'nominal_inductive2' derives strong induction
  2676 principles for inductive definitions.  In contrast to
  2677 'nominal_inductive', which can only deal with a fixed number of
  2678 binders, it can deal with arbitrary expressions standing for sets of
  2679 atoms to be avoided.  The only inductive definition we have at the
  2680 moment that needs this generalisation is the typing rule for Lets in
  2681 the algorithm W:
  2682 
  2683  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2684  -----------------------------------------------------------------
  2685          Gamma |- Let x be t1 in t2 : T2
  2686 
  2687 In this rule one wants to avoid all the binders that are introduced by
  2688 "close Gamma T1".  We are looking for other examples where this
  2689 feature might be useful.  Please let us know.
  2690 
  2691 
  2692 *** HOLCF ***
  2693 
  2694 * Reimplemented the simplification procedure for proving continuity
  2695 subgoals.  The new simproc is extensible; users can declare additional
  2696 continuity introduction rules with the attribute [cont2cont].
  2697 
  2698 * The continuity simproc now uses a different introduction rule for
  2699 solving continuity subgoals on terms with lambda abstractions.  In
  2700 some rare cases the new simproc may fail to solve subgoals that the
  2701 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2702 Potential INCOMPATIBILITY.
  2703 
  2704 * Command 'fixrec': specification syntax now conforms to the general
  2705 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2706 examples.  INCOMPATIBILITY.
  2707 
  2708 
  2709 *** ZF ***
  2710 
  2711 * Proof of Zorn's Lemma for partial orders.
  2712 
  2713 
  2714 *** ML ***
  2715 
  2716 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2717 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2718 depends on multithreading, so timouts will not work before Poly/ML
  2719 5.2.1!
  2720 
  2721 * High-level support for concurrent ML programming, see
  2722 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2723 particularly convenient to organize independent functional
  2724 computations.  The concept of "synchronized variables" provides a
  2725 higher-order interface for components with shared state, avoiding the
  2726 delicate details of mutexes and condition variables.  (Requires
  2727 Poly/ML 5.2.1 or later.)
  2728 
  2729 * ML bindings produced via Isar commands are stored within the Isar
  2730 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2731 become thread-safe and work with undo as expected (concerning
  2732 top-level bindings, not side-effects on global references).
  2733 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2734 compiler at runtime; really global bindings need to be given outside a
  2735 theory.  (Requires Poly/ML 5.2 or later.)
  2736 
  2737 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2738 context.  Top-level ML bindings are stored within the proof context in
  2739 a purely sequential fashion, disregarding the nested proof structure.
  2740 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2741 proof.  (Requires Poly/ML 5.2 or later.)
  2742 
  2743 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2744 and Method.setup, as well as Isar commands 'attribute_setup' and
  2745 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2746 existing code accordingly, or use plain 'setup' together with old
  2747 Method.add_method.
  2748 
  2749 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2750 to 'a -> thm, while results are always tagged with an authentic oracle
  2751 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2752 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2753 accordingly.  Note that extra performance may be gained by producing
  2754 the cterm carefully, avoiding slow Thm.cterm_of.
  2755 
  2756 * Simplified interface for defining document antiquotations via
  2757 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2758 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2759 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2760 examples.
  2761 
  2762 * More systematic treatment of long names, abstract name bindings, and
  2763 name space operations.  Basic operations on qualified names have been
  2764 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2765 Long_Name.append.  Old type bstring has been mostly replaced by
  2766 abstract type binding (see structure Binding), which supports precise
  2767 qualification by packages and local theory targets, as well as proper
  2768 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2769 bstring values into Binding.name, or better pass through abstract
  2770 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2771 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2772 
  2773 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2774 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2775 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2776 
  2777 * Disposed old type and term read functions (Sign.read_def_typ,
  2778 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2779 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2780 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2781 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2782 resort for legacy applications.
  2783 
  2784 * Disposed old declarations, tactics, tactic combinators that refer to
  2785 the simpset or claset of an implicit theory (such as Addsimps,
  2786 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2787 embedded ML text, or local_simpset_of with a proper context passed as
  2788 explicit runtime argument.
  2789 
  2790 * Rules and tactics that read instantiations (read_instantiate,
  2791 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2792 context, which is required for parsing and type-checking.  Moreover,
  2793 the variables are specified as plain indexnames, not string encodings
  2794 thereof.  INCOMPATIBILITY.
  2795 
  2796 * Generic Toplevel.add_hook interface allows to analyze the result of
  2797 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2798 for theorem dependency output of transactions resulting in a new
  2799 theory state.
  2800 
  2801 * ML antiquotations: block-structured compilation context indicated by
  2802 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2803 
  2804   @{binding name}                         - basic name binding
  2805   @{let ?pat = term}                      - term abbreviation (HO matching)
  2806   @{note name = fact}                     - fact abbreviation
  2807   @{thm fact}                             - singleton fact (with attributes)
  2808   @{thms fact}                            - general fact (with attributes)
  2809   @{lemma prop by method}                 - singleton goal
  2810   @{lemma prop by meth1 meth2}            - singleton goal
  2811   @{lemma prop1 ... propN by method}      - general goal
  2812   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2813   @{lemma (open) ...}                     - open derivation
  2814 
  2815 
  2816 *** System ***
  2817 
  2818 * The Isabelle "emacs" tool provides a specific interface to invoke
  2819 Proof General / Emacs, with more explicit failure if that is not
  2820 installed (the old isabelle-interface script silently falls back on
  2821 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2822 installation location of the Proof General distribution.
  2823 
  2824 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2825 the Isabelle process into a JVM/Scala application.  See
  2826 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2827 process wrapper has been discontinued.)
  2828 
  2829 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2830 
  2831 * Various status messages (with exact source position information) are
  2832 emitted, if proper markup print mode is enabled.  This allows
  2833 user-interface components to provide detailed feedback on internal
  2834 prover operations.
  2835 
  2836 
  2837 
  2838 New in Isabelle2008 (June 2008)
  2839 -------------------------------
  2840 
  2841 *** General ***
  2842 
  2843 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2844 and updated, with formally checked references as hyperlinks.
  2845 
  2846 * Theory loader: use_thy (and similar operations) no longer set the
  2847 implicit ML context, which was occasionally hard to predict and in
  2848 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2849 provides a proper context already.
  2850 
  2851 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2852 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2853 'use' within a theory file will do the job.
  2854 
  2855 * Name space merge now observes canonical order, i.e. the second space
  2856 is inserted into the first one, while existing entries in the first
  2857 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2858 swap theory imports.
  2859 
  2860 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2861 INCOMPATIBILITY in identifier syntax etc.
  2862 
  2863 * Outer syntax: string tokens no longer admit escaped white space,
  2864 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2865 white space without escapes.
  2866 
  2867 * Outer syntax: string tokens may contain arbitrary character codes
  2868 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2869 "foo_bar".
  2870 
  2871 
  2872 *** Pure ***
  2873 
  2874 * Context-dependent token translations.  Default setup reverts locally
  2875 fixed variables, and adds hilite markup for undeclared frees.
  2876 
  2877 * Unused theorems can be found using the new command 'unused_thms'.
  2878 There are three ways of invoking it:
  2879 
  2880 (1) unused_thms
  2881      Only finds unused theorems in the current theory.
  2882 
  2883 (2) unused_thms thy_1 ... thy_n -
  2884      Finds unused theorems in the current theory and all of its ancestors,
  2885      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2886 
  2887 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2888      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2889      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2890      their ancestors.
  2891 
  2892 In order to increase the readability of the list produced by
  2893 unused_thms, theorems that have been created by a particular instance
  2894 of a theory command such as 'inductive' or 'function' are considered
  2895 to belong to the same "group", meaning that if at least one theorem in
  2896 this group is used, the other theorems in the same group are no longer
  2897 reported as unused.  Moreover, if all theorems in the group are
  2898 unused, only one theorem in the group is displayed.
  2899 
  2900 Note that proof objects have to be switched on in order for
  2901 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2902 usually the case when using Proof General with the default settings).
  2903 
  2904 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2905 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2906 duplicate fact bindings, or even accidental fact duplications.  Note
  2907 that tools may maintain dynamically scoped facts systematically, using
  2908 PureThy.add_thms_dynamic.
  2909 
  2910 * Command 'hide' now allows to hide from "fact" name space as well.
  2911 
  2912 * Eliminated destructive theorem database, simpset, claset, and
  2913 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2914 update of theories within ML code.
  2915 
  2916 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2917 INCOMPATIBILITY, object-logics depending on former Pure require
  2918 additional setup PureThy.old_appl_syntax_setup; object-logics
  2919 depending on former CPure need to refer to Pure.
  2920 
  2921 * Commands 'use' and 'ML' are now purely functional, operating on
  2922 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2923 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2924 INCOMPATIBILITY.
  2925 
  2926 * Command 'setup': discontinued implicit version with ML reference.
  2927 
  2928 * Instantiation target allows for simultaneous specification of class
  2929 instance operations together with an instantiation proof.
  2930 Type-checking phase allows to refer to class operations uniformly.
  2931 See src/HOL/Complex/Complex.thy for an Isar example and
  2932 src/HOL/Library/Eval.thy for an ML example.
  2933 
  2934 * Indexing of literal facts: be more serious about including only
  2935 facts from the visible specification/proof context, but not the
  2936 background context (locale etc.).  Affects `prop` notation and method
  2937 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2938 situations.
  2939 
  2940 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2941 "(open)" option, which used to expose internal bound variables to the
  2942 proof text.
  2943 
  2944 * Isar statements: removed obsolete case "rule_context".
  2945 INCOMPATIBILITY, better use explicit fixes/assumes.
  2946 
  2947 * Locale proofs: default proof step now includes 'unfold_locales';
  2948 hence 'proof' without argument may be used to unfold locale
  2949 predicates.
  2950 
  2951 
  2952 *** Document preparation ***
  2953 
  2954 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2955 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2956 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2957 spot); renamed link color from "darkblue" to "linkcolor" (default
  2958 value unchanged, can be redefined via \definecolor); no longer sets
  2959 "a4paper" option (unnecessary or even intrusive).
  2960 
  2961 * Antiquotation @{lemma A method} proves proposition A by the given
  2962 method (either a method name or a method name plus (optional) method
  2963 arguments in parentheses) and prints A just like @{prop A}.
  2964 
  2965 
  2966 *** HOL ***
  2967 
  2968 * New primrec package.  Specification syntax conforms in style to
  2969 definition/function/....  No separate induction rule is provided.  The
  2970 "primrec" command distinguishes old-style and new-style specifications
  2971 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2972 When adjusting theories, beware: constants stemming from new-style
  2973 primrec specifications have authentic syntax.
  2974 
  2975 * Metis prover is now an order of magnitude faster, and also works
  2976 with multithreading.
  2977 
  2978 * Metis: the maximum number of clauses that can be produced from a
  2979 theorem is now given by the attribute max_clauses.  Theorems that
  2980 exceed this number are ignored, with a warning printed.
  2981 
  2982 * Sledgehammer no longer produces structured proofs by default. To
  2983 enable, declare [[sledgehammer_full = true]].  Attributes
  2984 reconstruction_modulus, reconstruction_sorts renamed
  2985 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2986 
  2987 * Method "induct_scheme" derives user-specified induction rules
  2988 from well-founded induction and completeness of patterns. This factors
  2989 out some operations that are done internally by the function package
  2990 and makes them available separately.  See
  2991 src/HOL/ex/Induction_Scheme.thy for examples.
  2992 
  2993 * More flexible generation of measure functions for termination
  2994 proofs: Measure functions can be declared by proving a rule of the
  2995 form "is_measure f" and giving it the [measure_function] attribute.
  2996 The "is_measure" predicate is logically meaningless (always true), and
  2997 just guides the heuristic.  To find suitable measure functions, the
  2998 termination prover sets up the goal "is_measure ?f" of the appropriate
  2999 type and generates all solutions by prolog-style backwards proof using
  3000 the declared rules.
  3001 
  3002 This setup also deals with rules like 
  3003 
  3004   "is_measure f ==> is_measure (list_size f)"
  3005 
  3006 which accommodates nested datatypes that recurse through lists.
  3007 Similar rules are predeclared for products and option types.
  3008 
  3009 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  3010 
  3011   INCOMPATIBILITIES:
  3012 
  3013   - Definitions of overloaded constants on sets have to be replaced by
  3014     definitions on => and bool.
  3015 
  3016   - Some definitions of overloaded operators on sets can now be proved
  3017     using the definitions of the operators on => and bool.  Therefore,
  3018     the following theorems have been renamed:
  3019 
  3020       subset_def   -> subset_eq
  3021       psubset_def  -> psubset_eq
  3022       set_diff_def -> set_diff_eq
  3023       Compl_def    -> Compl_eq
  3024       Sup_set_def  -> Sup_set_eq
  3025       Inf_set_def  -> Inf_set_eq
  3026       sup_set_def  -> sup_set_eq
  3027       inf_set_def  -> inf_set_eq
  3028 
  3029   - Due to the incompleteness of the HO unification algorithm, some
  3030     rules such as subst may require manual instantiation, if some of
  3031     the unknowns in the rule is a set.
  3032 
  3033   - Higher order unification and forward proofs:
  3034     The proof pattern
  3035 
  3036       have "P (S::'a set)" <...>
  3037       then have "EX S. P S" ..
  3038 
  3039     no longer works (due to the incompleteness of the HO unification
  3040     algorithm) and must be replaced by the pattern
  3041 
  3042       have "EX S. P S"
  3043       proof
  3044         show "P S" <...>
  3045       qed
  3046 
  3047   - Calculational reasoning with subst (or similar rules):
  3048     The proof pattern
  3049 
  3050       have "P (S::'a set)" <...>
  3051       also have "S = T" <...>
  3052       finally have "P T" .
  3053 
  3054     no longer works (for similar reasons as the previous example) and
  3055     must be replaced by something like
  3056 
  3057       have "P (S::'a set)" <...>
  3058       moreover have "S = T" <...>
  3059       ultimately have "P T" by simp
  3060 
  3061   - Tactics or packages written in ML code:
  3062     Code performing pattern matching on types via
  3063 
  3064       Type ("set", [T]) => ...
  3065 
  3066     must be rewritten. Moreover, functions like strip_type or
  3067     binder_types no longer return the right value when applied to a
  3068     type of the form
  3069 
  3070       T1 => ... => Tn => U => bool
  3071 
  3072     rather than
  3073 
  3074       T1 => ... => Tn => U set
  3075 
  3076 * Merged theories Wellfounded_Recursion, Accessible_Part and
  3077 Wellfounded_Relations to theory Wellfounded.
  3078 
  3079 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  3080 
  3081 * Class finite no longer treats UNIV as class parameter.  Use class
  3082 enum from theory Library/Enum instead to achieve a similar effect.
  3083 INCOMPATIBILITY.
  3084 
  3085 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  3086 and "Cons".  INCOMPATIBILITY.
  3087 
  3088 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  3089 Potential INCOMPATIBILITY.
  3090 
  3091 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  3092 injective_fst_snd removed, use split_eta and prod_eqI instead.
  3093 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  3094 
  3095 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  3096 the same name in theory Orderings:
  3097 
  3098   less_trans
  3099   less_linear
  3100   le_imp_less_or_eq
  3101   le_less_trans
  3102   less_le_trans
  3103   less_not_sym
  3104   less_asym
  3105 
  3106 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  3107 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  3108 and different variable names.
  3109 
  3110 * Library/Option_ord.thy: Canonical order on option type.
  3111 
  3112 * Library/RBT.thy: Red-black trees, an efficient implementation of
  3113 finite maps.
  3114 
  3115 * Library/Countable.thy: Type class for countable types.
  3116 
  3117 * Theory Int: The representation of numerals has changed.  The infix
  3118 operator BIT and the bit datatype with constructors B0 and B1 have
  3119 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  3120 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  3121 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  3122 accordingly.
  3123 
  3124 * Theory Nat: definition of <= and < on natural numbers no longer
  3125 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  3126 le_def and less_def have disappeared.  Consider lemmas not_less
  3127 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  3128 
  3129 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  3130 (whose purpose mainly is for various fold_set functionals) have been
  3131 abandoned in favor of the existing algebraic classes
  3132 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  3133 lower_semilattice (resp. upper_semilattice) and linorder.
  3134 INCOMPATIBILITY.
  3135 
  3136 * Theory Transitive_Closure: induct and cases rules now declare proper
  3137 case_names ("base" and "step").  INCOMPATIBILITY.
  3138 
  3139 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  3140 lattices.  The form set-specific version is available as
  3141 Inductive.lfp_ordinal_induct_set.
  3142 
  3143 * Renamed theorems "power.simps" to "power_int.simps".
  3144 INCOMPATIBILITY.
  3145 
  3146 * Class semiring_div provides basic abstract properties of semirings
  3147 with division and modulo operations.  Subsumes former class dvd_mod.
  3148 
  3149 * Merged theories IntDef, Numeral and IntArith into unified theory
  3150 Int.  INCOMPATIBILITY.
  3151 
  3152 * Theory Library/Code_Index: type "index" now represents natural
  3153 numbers rather than integers.  INCOMPATIBILITY.
  3154 
  3155 * New class "uminus" with operation "uminus" (split of from class
  3156 "minus" which now only has operation "minus", binary).
  3157 INCOMPATIBILITY.
  3158 
  3159 * Constants "card", "internal_split", "option_map" now with authentic
  3160 syntax.  INCOMPATIBILITY.
  3161 
  3162 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3163 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3164 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3165 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3166 Sup_set_def, le_def, less_def, option_map_def now with object
  3167 equality.  INCOMPATIBILITY.
  3168 
  3169 * Records. Removed K_record, and replaced it by pure lambda term
  3170 %x. c. The simplifier setup is now more robust against eta expansion.
  3171 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3172 
  3173 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3174 
  3175 * Library/ListVector: new theory of arithmetic vector operations.
  3176 
  3177 * Library/Order_Relation: new theory of various orderings as sets of
  3178 pairs.  Defines preorders, partial orders, linear orders and
  3179 well-orders on sets and on types.
  3180 
  3181 
  3182 *** ZF ***
  3183 
  3184 * Renamed some theories to allow to loading both ZF and HOL in the
  3185 same session:
  3186 
  3187   Datatype  -> Datatype_ZF
  3188   Inductive -> Inductive_ZF
  3189   Int       -> Int_ZF
  3190   IntDiv    -> IntDiv_ZF
  3191   Nat       -> Nat_ZF
  3192   List      -> List_ZF
  3193   Main      -> Main_ZF
  3194 
  3195 INCOMPATIBILITY: ZF theories that import individual theories below
  3196 Main might need to be adapted.  Regular theory Main is still
  3197 available, as trivial extension of Main_ZF.
  3198 
  3199 
  3200 *** ML ***
  3201 
  3202 * ML within Isar: antiquotation @{const name} or @{const
  3203 name(typargs)} produces statically-checked Const term.
  3204 
  3205 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3206 (of the same name).  Removed obsolete print command.
  3207 
  3208 * Removed obsolete "use_legacy_bindings" function.
  3209 
  3210 * The ``print mode'' is now a thread-local value derived from a global
  3211 template (the former print_mode reference), thus access becomes
  3212 non-critical.  The global print_mode reference is for session
  3213 management only; user-code should use print_mode_value,
  3214 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3215 
  3216 * Functions system/system_out provide a robust way to invoke external
  3217 shell commands, with propagation of interrupts (requires Poly/ML
  3218 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3219 
  3220 
  3221 *** System ***
  3222 
  3223 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3224 in accordance with Proof General 3.7, which prefers GNU emacs.
  3225 
  3226 * isatool tty runs Isabelle process with plain tty interaction;
  3227 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3228 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3229 
  3230 * isatool browser now works with Cygwin as well, using general
  3231 "javapath" function defined in Isabelle process environment.
  3232 
  3233 * YXML notation provides a simple and efficient alternative to
  3234 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3235 isatool yxml as described in the Isabelle system manual.
  3236 
  3237 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3238 provides general wrapper for managing an Isabelle process in a robust
  3239 fashion, with ``cooked'' output from stdin/stderr.
  3240 
  3241 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3242 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3243 
  3244 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3245 way of changing the user's settings is via
  3246 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3247 script.
  3248 
  3249 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3250 cores of the underlying machine, which is a good starting point for
  3251 optimal performance tuning.  The corresponding usedir option -M allows
  3252 "max" as an alias for "0".  WARNING: does not work on certain versions
  3253 of Mac OS (with Poly/ML 5.1).
  3254 
  3255 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3256 adverse effect of Isabelle flooding interactive front-ends (notably
  3257 ProofGeneral / XEmacs).
  3258 
  3259 
  3260 
  3261 New in Isabelle2007 (November 2007)
  3262 -----------------------------------
  3263 
  3264 *** General ***
  3265 
  3266 * More uniform information about legacy features, notably a
  3267 warning/error of "Legacy feature: ...", depending on the state of the
  3268 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3269 legacy features will disappear eventually.
  3270 
  3271 * Theory syntax: the header format ``theory A = B + C:'' has been
  3272 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3273 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3274 
  3275 * Theory syntax: the old non-Isar theory file format has been
  3276 discontinued altogether.  Note that ML proof scripts may still be used
  3277 with Isar theories; migration is usually quite simple with the ML
  3278 function use_legacy_bindings.  INCOMPATIBILITY.
  3279 
  3280 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3281 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3282 quotes.
  3283 
  3284 * Theory loader: be more serious about observing the static theory
  3285 header specifications (including optional directories), but not the
  3286 accidental file locations of previously successful loads.  The strict
  3287 update policy of former update_thy is now already performed by
  3288 use_thy, so the former has been removed; use_thys updates several
  3289 theories simultaneously, just as 'imports' within a theory header
  3290 specification, but without merging the results.  Potential
  3291 INCOMPATIBILITY: may need to refine theory headers and commands
  3292 ROOT.ML which depend on load order.
  3293 
  3294 * Theory loader: optional support for content-based file
  3295 identification, instead of the traditional scheme of full physical
  3296 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3297 (cf. the system manual).  The new scheme allows to work with
  3298 non-finished theories in persistent session images, such that source
  3299 files may be moved later on without requiring reloads.
  3300 
  3301 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3302 file (with the same base name as the theory) are considered a legacy
  3303 feature, which will disappear eventually. Even now, the theory loader
  3304 no longer maintains dependencies on such files.
  3305 
  3306 * Syntax: the scope for resolving ambiguities via type-inference is
  3307 now limited to individual terms, instead of whole simultaneous
  3308 specifications as before. This greatly reduces the complexity of the
  3309 syntax module and improves flexibility by separating parsing and
  3310 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3311 'fixes' etc.) are required in rare situations.
  3312 
  3313 * Syntax: constants introduced by new-style packages ('definition',
  3314 'abbreviation' etc.) are passed through the syntax module in
  3315 ``authentic mode''. This means that associated mixfix annotations
  3316 really stick to such constants, independently of potential name space
  3317 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3318 trees are represented slightly differently, may need to adapt syntax
  3319 translations accordingly. Use CONST marker in 'translations' and
  3320 @{const_syntax} antiquotation in 'parse_translation' etc.
  3321 
  3322 * Legacy goal package: reduced interface to the bare minimum required
  3323 to keep existing proof scripts running.  Most other user-level
  3324 functions are now part of the OldGoals structure, which is *not* open
  3325 by default (consider isatool expandshort before open OldGoals).
  3326 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3327 these tend to cause confusion about the actual goal (!) context being
  3328 used here, which is not necessarily the same as the_context().
  3329 
  3330 * Command 'find_theorems': supports "*" wild-card in "name:"
  3331 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3332 support a specific search form (see ProofGeneral/CHANGES).
  3333 
  3334 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3335 by default, which means that "prems" (and also "fixed variables") are
  3336 suppressed from proof state output.  Note that the ProofGeneral
  3337 settings mechanism allows to change and save options persistently, but
  3338 older versions of Isabelle will fail to start up if a negative prems
  3339 limit is imposed.
  3340 
  3341 * Local theory targets may be specified by non-nested blocks of
  3342 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3343 contain definitions, theorems etc., including any derived mechanism
  3344 that has been implemented on top of these primitives.  This concept
  3345 generalizes the existing ``theorem (in ...)'' towards more versatility
  3346 and scalability.
  3347 
  3348 * Proof General interface: proper undo of final 'end' command;
  3349 discontinued Isabelle/classic mode (ML proof scripts).
  3350 
  3351 
  3352 *** Document preparation ***
  3353 
  3354 * Added antiquotation @{theory name} which prints the given name,
  3355 after checking that it refers to a valid ancestor theory in the
  3356 current context.
  3357 
  3358 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3359 check the given source text as ML type/structure, printing verbatim.
  3360 
  3361 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3362 "c args == rhs" given in the current context.  (Any number of
  3363 arguments may be given on the LHS.)
  3364 
  3365 
  3366 *** Pure ***
  3367 
  3368 * The 'class' package offers a combination of axclass and locale to
  3369 achieve Haskell-like type classes in Isabelle.  Definitions and
  3370 theorems within a class context produce both relative results (with
  3371 implicit parameters according to the locale context), and polymorphic
  3372 constants with qualified polymorphism (according to the class
  3373 context).  Within the body context of a 'class' target, a separate
  3374 syntax layer ("user space type system") takes care of converting
  3375 between global polymorphic consts and internal locale representation.
  3376 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3377 "isatool doc classes" provides a tutorial.
  3378 
  3379 * Generic code generator framework allows to generate executable
  3380 code for ML and Haskell (including Isabelle classes).  A short usage
  3381 sketch:
  3382 
  3383     internal compilation:
  3384         export_code <list of constants (term syntax)> in SML
  3385     writing SML code to a file:
  3386         export_code <list of constants (term syntax)> in SML <filename>
  3387     writing OCaml code to a file:
  3388         export_code <list of constants (term syntax)> in OCaml <filename>
  3389     writing Haskell code to a bunch of files:
  3390         export_code <list of constants (term syntax)> in Haskell <filename>
  3391 
  3392     evaluating closed propositions to True/False using code generation:
  3393         method ``eval''
  3394 
  3395 Reasonable default setup of framework in HOL.
  3396 
  3397 Theorem attributs for selecting and transforming function equations theorems:
  3398 
  3399     [code fun]:        select a theorem as function equation for a specific constant
  3400     [code fun del]:    deselect a theorem as function equation for a specific constant
  3401     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3402     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3403 
  3404 User-defined serializations (target in {SML, OCaml, Haskell}):
  3405 
  3406     code_const <and-list of constants (term syntax)>
  3407       {(target) <and-list of const target syntax>}+
  3408 
  3409     code_type <and-list of type constructors>
  3410       {(target) <and-list of type target syntax>}+
  3411 
  3412     code_instance <and-list of instances>
  3413       {(target)}+
  3414         where instance ::= <type constructor> :: <class>
  3415 
  3416     code_class <and_list of classes>
  3417       {(target) <and-list of class target syntax>}+
  3418         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3419 
  3420 code_instance and code_class only are effective to target Haskell.
  3421 
  3422 For example usage see src/HOL/ex/Codegenerator.thy and
  3423 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3424 generation from Isabelle/HOL theories is available via "isatool doc
  3425 codegen".
  3426 
  3427 * Code generator: consts in 'consts_code' Isar commands are now
  3428 referred to by usual term syntax (including optional type
  3429 annotations).
  3430 
  3431 * Command 'no_translations' removes translation rules from theory
  3432 syntax.
  3433 
  3434 * Overloaded definitions are now actually checked for acyclic
  3435 dependencies.  The overloading scheme is slightly more general than
  3436 that of Haskell98, although Isabelle does not demand an exact
  3437 correspondence to type class and instance declarations.
  3438 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3439 exotic versions of overloading -- at the discretion of the user!
  3440 
  3441 Polymorphic constants are represented via type arguments, i.e. the
  3442 instantiation that matches an instance against the most general
  3443 declaration given in the signature.  For example, with the declaration
  3444 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3445 as c(nat).  Overloading is essentially simultaneous structural
  3446 recursion over such type arguments.  Incomplete specification patterns
  3447 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3448 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3449 Command 'print_theory' outputs the normalized system of recursive
  3450 equations, see section "definitions".
  3451 
  3452 * Configuration options are maintained within the theory or proof
  3453 context (with name and type bool/int/string), providing a very simple
  3454 interface to a poor-man's version of general context data.  Tools may
  3455 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3456 these values using Config.get etc.  Users may change options via an
  3457 associated attribute of the same name.  This form of context
  3458 declaration works particularly well with commands 'declare' or
  3459 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3460 very easy to avoid global references, which would not observe Isar
  3461 toplevel undo/redo and fail to work with multithreading.
  3462 
  3463 Various global ML references of Pure and HOL have been turned into
  3464 configuration options:
  3465 
  3466   Unify.search_bound		unify_search_bound
  3467   Unify.trace_bound		unify_trace_bound
  3468   Unify.trace_simp		unify_trace_simp
  3469   Unify.trace_types		unify_trace_types
  3470   Simplifier.simp_depth_limit	simp_depth_limit
  3471   Blast.depth_limit		blast_depth_limit
  3472   DatatypeProp.dtK		datatype_distinctness_limit
  3473   fast_arith_neq_limit  	fast_arith_neq_limit
  3474   fast_arith_split_limit	fast_arith_split_limit
  3475 
  3476 * Named collections of theorems may be easily installed as context
  3477 data using the functor NamedThmsFun (see also
  3478 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3479 attributes; there is also a toplevel print command.  This facility is
  3480 just a common case of general context data, which is the preferred way
  3481 for anything more complex than just a list of facts in canonical
  3482 order.
  3483 
  3484 * Isar: command 'declaration' augments a local theory by generic
  3485 declaration functions written in ML.  This enables arbitrary content
  3486 being added to the context, depending on a morphism that tells the
  3487 difference of the original declaration context wrt. the application
  3488 context encountered later on.
  3489 
  3490 * Isar: proper interfaces for simplification procedures.  Command
  3491 'simproc_setup' declares named simprocs (with match patterns, and body
  3492 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3493 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3494 
  3495 * Isar: an extra pair of brackets around attribute declarations
  3496 abbreviates a theorem reference involving an internal dummy fact,
  3497 which will be ignored later --- only the effect of the attribute on
  3498 the background context will persist.  This form of in-place
  3499 declarations is particularly useful with commands like 'declare' and
  3500 'using', for example ``have A using [[simproc a]] by simp''.
  3501 
  3502 * Isar: method "assumption" (and implicit closing of subproofs) now
  3503 takes simple non-atomic goal assumptions into account: after applying
  3504 an assumption as a rule the resulting subgoals are solved by atomic
  3505 assumption steps.  This is particularly useful to finish 'obtain'
  3506 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3507 without referring to the original premise "!!x. P x ==> thesis" in the
  3508 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3509 more permissive.
  3510 
  3511 * Isar: implicit use of prems from the Isar proof context is
  3512 considered a legacy feature.  Common applications like ``have A .''
  3513 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3514 referencing facts explicitly here improves readability and
  3515 maintainability of proof texts.
  3516 
  3517 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3518 the obtained context from the course of reasoning!  For example:
  3519 
  3520   assume "EX x y. A x & B y"   -- "any previous fact"
  3521   then guess x and y by clarify
  3522 
  3523 This technique is potentially adventurous, depending on the facts and
  3524 proof tools being involved here.
  3525 
  3526 * Isar: known facts from the proof context may be specified as literal
  3527 propositions, using ASCII back-quote syntax.  This works wherever
  3528 named facts used to be allowed so far, in proof commands, proof
  3529 methods, attributes etc.  Literal facts are retrieved from the context
  3530 according to unification of type and term parameters.  For example,
  3531 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3532 theorems in the current context, then these are valid literal facts:
  3533 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3534 
  3535 There is also a proof method "fact" which does the same composition
  3536 for explicit goal states, e.g. the following proof texts coincide with
  3537 certain special cases of literal facts:
  3538 
  3539   have "A" by fact                 ==  note `A`
  3540   have "A ==> B" by fact           ==  note `A ==> B`
  3541   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3542   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3543 
  3544 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3545 outer syntax.  Thus symbolic identifiers may be used without
  3546 additional white space in declarations like this: ``assume *: A''.
  3547 
  3548 * Isar: 'print_facts' prints all local facts of the current context,
  3549 both named and unnamed ones.
  3550 
  3551 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3552 
  3553   def x == "t" and y == "u"
  3554 
  3555 * Isar: added command 'unfolding', which is structurally similar to
  3556 'using', but affects both the goal state and facts by unfolding given
  3557 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3558 'unfolded' attribute may be replaced by first-class proof text.
  3559 
  3560 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3561 and command 'unfolding' now all support object-level equalities
  3562 (potentially conditional).  The underlying notion of rewrite rule is
  3563 analogous to the 'rule_format' attribute, but *not* that of the
  3564 Simplifier (which is usually more generous).
  3565 
  3566 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3567 premises of a theorem by n. Useful in conjunction with drule.
  3568 
  3569 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3570 method expression within a sandbox consisting of the first N
  3571 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3572 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3573 simplifies all new goals that emerge from applying rule foo to the
  3574 originally first one.
  3575 
  3576 * Isar: schematic goals are no longer restricted to higher-order
  3577 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3578 expected.
  3579 
  3580 * Isar: the conclusion of a long theorem statement is now either
  3581 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3582 (essentially a disjunction of cases with local parameters and
  3583 assumptions).  The latter allows to express general elimination rules
  3584 adequately; in this notation common elimination rules look like this:
  3585 
  3586   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3587     assumes "EX x. P x"
  3588     obtains x where "P x"
  3589 
  3590   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3591     assumes "A & B"
  3592     obtains A and B
  3593 
  3594   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3595     assumes "A | B"
  3596     obtains
  3597       A
  3598     | B
  3599 
  3600 The subsequent classical rules even refer to the formal "thesis"
  3601 explicitly:
  3602 
  3603   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3604     obtains "~ thesis"
  3605 
  3606   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3607     obtains "thesis ==> something"
  3608 
  3609 The actual proof of an 'obtains' statement is analogous to that of the
  3610 Isar proof element 'obtain', only that there may be several cases.
  3611 Optional case names may be specified in parentheses; these will be
  3612 available both in the present proof and as annotations in the
  3613 resulting rule, for later use with the 'cases' method (cf. attribute
  3614 case_names).
  3615 
  3616 * Isar: the assumptions of a long theorem statement are available as
  3617 "assms" fact in the proof context.  This is more appropriate than the
  3618 (historical) "prems", which refers to all assumptions of the current
  3619 context, including those from the target locale, proof body etc.
  3620 
  3621 * Isar: 'print_statement' prints theorems from the current theory or
  3622 proof context in long statement form, according to the syntax of a
  3623 top-level lemma.
  3624 
  3625 * Isar: 'obtain' takes an optional case name for the local context
  3626 introduction rule (default "that").
  3627 
  3628 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3629 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3630 to occur.
  3631 
  3632 * Pure: syntax "CONST name" produces a fully internalized constant
  3633 according to the current context.  This is particularly useful for
  3634 syntax translations that should refer to internal constant
  3635 representations independently of name spaces.
  3636 
  3637 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3638 instead of "FOO ". This allows multiple binder declarations to coexist
  3639 in the same context.  INCOMPATIBILITY.
  3640 
  3641 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3642 primitive that also works in a locale context (both for constants and
  3643 fixed variables). Type declaration and internal syntactic representation
  3644 of given constants retrieved from the context. Likewise, the
  3645 'no_notation' command allows to remove given syntax annotations from the
  3646 current context.
  3647 
  3648 * Isar/locales: new derived specification elements 'axiomatization',
  3649 'definition', 'abbreviation', which support type-inference, admit
  3650 object-level specifications (equality, equivalence).  See also the
  3651 isar-ref manual.  Examples:
  3652 
  3653   axiomatization
  3654     eq  (infix "===" 50) where
  3655     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3656 
  3657   definition "f x y = x + y + 1"
  3658   definition g where "g x = f x x"
  3659 
  3660   abbreviation
  3661     neq  (infix "=!=" 50) where
  3662     "x =!= y == ~ (x === y)"
  3663 
  3664 These specifications may be also used in a locale context.  Then the
  3665 constants being introduced depend on certain fixed parameters, and the
  3666 constant name is qualified by the locale base name.  An internal
  3667 abbreviation takes care for convenient input and output, making the
  3668 parameters implicit and using the original short name.  See also
  3669 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3670 entities from a monomorphic theory.
  3671 
  3672 Presently, abbreviations are only available 'in' a target locale, but
  3673 not inherited by general import expressions.  Also note that
  3674 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3675 'translations' in common applications.  The "no_abbrevs" print mode
  3676 prevents folding of abbreviations in term output.
  3677 
  3678 Concrete syntax is attached to specified constants in internal form,
  3679 independently of name spaces.  The parse tree representation is
  3680 slightly different -- use 'notation' instead of raw 'syntax', and
  3681 'translations' with explicit "CONST" markup to accommodate this.
  3682 
  3683 * Pure/Isar: unified syntax for new-style specification mechanisms
  3684 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3685 full type inference and dummy patterns ("_").  For example:
  3686 
  3687   definition "K x _ = x"
  3688 
  3689   inductive conj for A B
  3690   where "A ==> B ==> conj A B"
  3691 
  3692 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3693 the current context.  Print mode "no_abbrevs" prevents inversion of
  3694 abbreviations on output.
  3695 
  3696 * Isar/locales: improved parameter handling: use of locales "var" and
  3697 "struct" no longer necessary; - parameter renamings are no longer
  3698 required to be injective.  For example, this allows to define
  3699 endomorphisms as locale endom = homom mult mult h.
  3700 
  3701 * Isar/locales: changed the way locales with predicates are defined.
  3702 Instead of accumulating the specification, the imported expression is
  3703 now an interpretation.  INCOMPATIBILITY: different normal form of
  3704 locale expressions.  In particular, in interpretations of locales with
  3705 predicates, goals repesenting already interpreted fragments are not
  3706 removed automatically.  Use methods `intro_locales' and
  3707 `unfold_locales'; see below.
  3708 
  3709 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3710 provide backward reasoning on locales predicates.  The methods are
  3711 aware of interpretations and discharge corresponding goals.
  3712 `intro_locales' is less aggressive then `unfold_locales' and does not
  3713 unfold predicates to assumptions.
  3714 
  3715 * Isar/locales: the order in which locale fragments are accumulated
  3716 has changed.  This enables to override declarations from fragments due
  3717 to interpretations -- for example, unwanted simp rules.
  3718 
  3719 * Isar/locales: interpretation in theories and proof contexts has been
  3720 extended.  One may now specify (and prove) equations, which are
  3721 unfolded in interpreted theorems.  This is useful for replacing
  3722 defined concepts (constants depending on locale parameters) by
  3723 concepts already existing in the target context.  Example:
  3724 
  3725   interpretation partial_order ["op <= :: [int, int] => bool"]
  3726     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3727 
  3728 Typically, the constant `partial_order.less' is created by a
  3729 definition specification element in the context of locale
  3730 partial_order.
  3731 
  3732 * Method "induct": improved internal context management to support
  3733 local fixes and defines on-the-fly. Thus explicit meta-level
  3734 connectives !!  and ==> are rarely required anymore in inductive goals
  3735 (using object-logic connectives for this purpose has been long
  3736 obsolete anyway). Common proof patterns are explained in
  3737 src/HOL/Induct/Common_Patterns.thy, see also
  3738 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3739 examples.
  3740 
  3741 * Method "induct": improved handling of simultaneous goals. Instead of
  3742 introducing object-level conjunction, the statement is now split into
  3743 several conclusions, while the corresponding symbolic cases are nested
  3744 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3745 see src/HOL/Induct/Common_Patterns.thy, for example.
  3746 
  3747 * Method "induct": mutual induction rules are now specified as a list
  3748 of rule sharing the same induction cases. HOL packages usually provide
  3749 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3750 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3751 mutual induction rules differently, i.e. like this:
  3752 
  3753   (induct rule: foo_bar.inducts)
  3754   (induct set: foo bar)
  3755   (induct pred: foo bar)
  3756   (induct type: foo bar)
  3757 
  3758 The ML function ProjectRule.projections turns old-style rules into the
  3759 new format.
  3760 
  3761 * Method "coinduct": dual of induction, see
  3762 src/HOL/Library/Coinductive_List.thy for various examples.
  3763 
  3764 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3765 considered a legacy feature.
  3766 
  3767 * Attribute "symmetric" produces result with standardized schematic
  3768 variables (index 0).  Potential INCOMPATIBILITY.
  3769 
  3770 * Simplifier: by default the simplifier trace only shows top level
  3771 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3772 default. Thus there is less danger of being flooded by the trace. The
  3773 trace indicates where parts have been suppressed.
  3774   
  3775 * Provers/classical: removed obsolete classical version of elim_format
  3776 attribute; classical elim/dest rules are now treated uniformly when
  3777 manipulating the claset.
  3778 
  3779 * Provers/classical: stricter checks to ensure that supplied intro,
  3780 dest and elim rules are well-formed; dest and elim rules must have at
  3781 least one premise.
  3782 
  3783 * Provers/classical: attributes dest/elim/intro take an optional
  3784 weight argument for the rule (just as the Pure versions).  Weights are
  3785 ignored by automated tools, but determine the search order of single
  3786 rule steps.
  3787 
  3788 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3789 where the body does not mention the bound variable.  Note that dummy
  3790 patterns implicitly depend on their context of bounds, which makes
  3791 "{_. _}" match any set comprehension as expected.  Potential
  3792 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3793 constant "_idtdummy" in the binding position.
  3794 
  3795 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3796 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3797 for example "A -> B" => "Pi A (%_. B)".
  3798 
  3799 * Pure: 'class_deps' command visualizes the subclass relation, using
  3800 the graph browser tool.
  3801 
  3802 * Pure: 'print_theory' now suppresses certain internal declarations by
  3803 default; use '!' option for full details.
  3804 
  3805 
  3806 *** HOL ***
  3807 
  3808 * Method "metis" proves goals by applying the Metis general-purpose
  3809 resolution prover (see also http://gilith.com/software/metis/).
  3810 Examples are in the directory MetisExamples.  WARNING: the
  3811 Isabelle/HOL-Metis integration does not yet work properly with
  3812 multi-threading.
  3813   
  3814 * Command 'sledgehammer' invokes external automatic theorem provers as
  3815 background processes.  It generates calls to the "metis" method if
  3816 successful. These can be pasted into the proof.  Users do not have to
  3817 wait for the automatic provers to return.  WARNING: does not really
  3818 work with multi-threading.
  3819 
  3820 * New "auto_quickcheck" feature tests outermost goal statements for
  3821 potential counter-examples.  Controlled by ML references
  3822 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3823 5000 milliseconds).  Fails silently if statements is outside of
  3824 executable fragment, or any other codgenerator problem occurs.
  3825 
  3826 * New constant "undefined" with axiom "undefined x = undefined".
  3827 
  3828 * Added class "HOL.eq", allowing for code generation with polymorphic
  3829 equality.
  3830 
  3831 * Some renaming of class constants due to canonical name prefixing in
  3832 the new 'class' package:
  3833 
  3834     HOL.abs ~> HOL.abs_class.abs
  3835     HOL.divide ~> HOL.divide_class.divide
  3836     0 ~> HOL.zero_class.zero
  3837     1 ~> HOL.one_class.one
  3838     op + ~> HOL.plus_class.plus
  3839     op - ~> HOL.minus_class.minus
  3840     uminus ~> HOL.minus_class.uminus
  3841     op * ~> HOL.times_class.times
  3842     op < ~> HOL.ord_class.less
  3843     op <= > HOL.ord_class.less_eq
  3844     Nat.power ~> Power.power_class.power
  3845     Nat.size ~> Nat.size_class.size
  3846     Numeral.number_of ~> Numeral.number_class.number_of
  3847     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3848     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3849     Orderings.min ~> Orderings.ord_class.min
  3850     Orderings.max ~> Orderings.ord_class.max
  3851     Divides.op div ~> Divides.div_class.div
  3852     Divides.op mod ~> Divides.div_class.mod
  3853     Divides.op dvd ~> Divides.div_class.dvd
  3854 
  3855 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3856 
  3857 a) User-defined constants using any of the names "plus", "minus",
  3858 "times", "less" or "less_eq". The standard syntax translations for
  3859 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3860 names.
  3861 
  3862 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3863 INCOMPATIBILITY: use more specific names.
  3864 
  3865 c) Permutative equations (e.g. "a + b = b + a")
  3866 Since the change of names also changes the order of terms, permutative
  3867 rewrite rules may get applied in a different order. Experience shows
  3868 that this is rarely the case (only two adaptions in the whole Isabelle
  3869 distribution).  INCOMPATIBILITY: rewrite proofs
  3870 
  3871 d) ML code directly refering to constant names
  3872 This in general only affects hand-written proof tactics, simprocs and
  3873 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3874 Consider using @{const_name} antiquotation.
  3875 
  3876 * New class "default" with associated constant "default".
  3877 
  3878 * Function "sgn" is now overloaded and available on int, real, complex
  3879 (and other numeric types), using class "sgn".  Two possible defs of
  3880 sgn are given as equational assumptions in the classes sgn_if and
  3881 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3882 INCOMPATIBILITY.
  3883 
  3884 * Locale "partial_order" now unified with class "order" (cf. theory
  3885 Orderings), added parameter "less".  INCOMPATIBILITY.
  3886 
  3887 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3888 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3889 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3890 
  3891 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3892 changed order of proof goals in instance proofs.
  3893 
  3894 * The transitivity reasoner for partial and linear orders is set up
  3895 for classes "order" and "linorder".  Instances of the reasoner are available
  3896 in all contexts importing or interpreting the corresponding locales.
  3897 Method "order" invokes the reasoner separately; the reasoner
  3898 is also integrated with the Simplifier as a solver.  Diagnostic
  3899 command 'print_orders' shows the available instances of the reasoner
  3900 in the current context.
  3901 
  3902 * Localized monotonicity predicate in theory "Orderings"; integrated
  3903 lemmas max_of_mono and min_of_mono with this predicate.
  3904 INCOMPATIBILITY.
  3905 
  3906 * Formulation of theorem "dense" changed slightly due to integration
  3907 with new class dense_linear_order.
  3908 
  3909 * Uniform lattice theory development in HOL.
  3910 
  3911     constants "meet" and "join" now named "inf" and "sup"
  3912     constant "Meet" now named "Inf"
  3913 
  3914     classes "meet_semilorder" and "join_semilorder" now named
  3915       "lower_semilattice" and "upper_semilattice"
  3916     class "lorder" now named "lattice"
  3917     class "comp_lat" now named "complete_lattice"
  3918 
  3919     Instantiation of lattice classes allows explicit definitions
  3920     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3921 
  3922   INCOMPATIBILITY.  Theorem renames:
  3923 
  3924     meet_left_le            ~> inf_le1
  3925     meet_right_le           ~> inf_le2
  3926     join_left_le            ~> sup_ge1
  3927     join_right_le           ~> sup_ge2
  3928     meet_join_le            ~> inf_sup_ord
  3929     le_meetI                ~> le_infI
  3930     join_leI                ~> le_supI
  3931     le_meet                 ~> le_inf_iff
  3932     le_join                 ~> ge_sup_conv
  3933     meet_idempotent         ~> inf_idem
  3934     join_idempotent         ~> sup_idem
  3935     meet_comm               ~> inf_commute
  3936     join_comm               ~> sup_commute
  3937     meet_leI1               ~> le_infI1
  3938     meet_leI2               ~> le_infI2
  3939     le_joinI1               ~> le_supI1
  3940     le_joinI2               ~> le_supI2
  3941     meet_assoc              ~> inf_assoc
  3942     join_assoc              ~> sup_assoc
  3943     meet_left_comm          ~> inf_left_commute
  3944     meet_left_idempotent    ~> inf_left_idem
  3945     join_left_comm          ~> sup_left_commute
  3946     join_left_idempotent    ~> sup_left_idem
  3947     meet_aci                ~> inf_aci
  3948     join_aci                ~> sup_aci
  3949     le_def_meet             ~> le_iff_inf
  3950     le_def_join             ~> le_iff_sup
  3951     join_absorp2            ~> sup_absorb2
  3952     join_absorp1            ~> sup_absorb1
  3953     meet_absorp1            ~> inf_absorb1
  3954     meet_absorp2            ~> inf_absorb2
  3955     meet_join_absorp        ~> inf_sup_absorb
  3956     join_meet_absorp        ~> sup_inf_absorb
  3957     distrib_join_le         ~> distrib_sup_le
  3958     distrib_meet_le         ~> distrib_inf_le
  3959 
  3960     add_meet_distrib_left   ~> add_inf_distrib_left
  3961     add_join_distrib_left   ~> add_sup_distrib_left
  3962     is_join_neg_meet        ~> is_join_neg_inf
  3963     is_meet_neg_join        ~> is_meet_neg_sup
  3964     add_meet_distrib_right  ~> add_inf_distrib_right
  3965     add_join_distrib_right  ~> add_sup_distrib_right
  3966     add_meet_join_distribs  ~> add_sup_inf_distribs
  3967     join_eq_neg_meet        ~> sup_eq_neg_inf
  3968     meet_eq_neg_join        ~> inf_eq_neg_sup
  3969     add_eq_meet_join        ~> add_eq_inf_sup
  3970     meet_0_imp_0            ~> inf_0_imp_0
  3971     join_0_imp_0            ~> sup_0_imp_0
  3972     meet_0_eq_0             ~> inf_0_eq_0
  3973     join_0_eq_0             ~> sup_0_eq_0
  3974     neg_meet_eq_join        ~> neg_inf_eq_sup
  3975     neg_join_eq_meet        ~> neg_sup_eq_inf
  3976     join_eq_if              ~> sup_eq_if
  3977 
  3978     mono_meet               ~> mono_inf
  3979     mono_join               ~> mono_sup
  3980     meet_bool_eq            ~> inf_bool_eq
  3981     join_bool_eq            ~> sup_bool_eq
  3982     meet_fun_eq             ~> inf_fun_eq
  3983     join_fun_eq             ~> sup_fun_eq
  3984     meet_set_eq             ~> inf_set_eq
  3985     join_set_eq             ~> sup_set_eq
  3986     meet1_iff               ~> inf1_iff
  3987     meet2_iff               ~> inf2_iff
  3988     meet1I                  ~> inf1I
  3989     meet2I                  ~> inf2I
  3990     meet1D1                 ~> inf1D1
  3991     meet2D1                 ~> inf2D1
  3992     meet1D2                 ~> inf1D2
  3993     meet2D2                 ~> inf2D2
  3994     meet1E                  ~> inf1E
  3995     meet2E                  ~> inf2E
  3996     join1_iff               ~> sup1_iff
  3997     join2_iff               ~> sup2_iff
  3998     join1I1                 ~> sup1I1
  3999     join2I1                 ~> sup2I1
  4000     join1I1                 ~> sup1I1
  4001     join2I2                 ~> sup1I2
  4002     join1CI                 ~> sup1CI
  4003     join2CI                 ~> sup2CI
  4004     join1E                  ~> sup1E
  4005     join2E                  ~> sup2E
  4006 
  4007     is_meet_Meet            ~> is_meet_Inf
  4008     Meet_bool_def           ~> Inf_bool_def
  4009     Meet_fun_def            ~> Inf_fun_def
  4010     Meet_greatest           ~> Inf_greatest
  4011     Meet_lower              ~> Inf_lower
  4012     Meet_set_def            ~> Inf_set_def
  4013 
  4014     Sup_def                 ~> Sup_Inf
  4015     Sup_bool_eq             ~> Sup_bool_def
  4016     Sup_fun_eq              ~> Sup_fun_def
  4017     Sup_set_eq              ~> Sup_set_def
  4018 
  4019     listsp_meetI            ~> listsp_infI
  4020     listsp_meet_eq          ~> listsp_inf_eq
  4021 
  4022     meet_min                ~> inf_min
  4023     join_max                ~> sup_max
  4024 
  4025 * Added syntactic class "size"; overloaded constant "size" now has
  4026 type "'a::size ==> bool"
  4027 
  4028 * Internal reorganisation of `size' of datatypes: size theorems
  4029 "foo.size" are no longer subsumed by "foo.simps" (but are still
  4030 simplification rules by default!); theorems "prod.size" now named
  4031 "*.size".
  4032 
  4033 * Class "div" now inherits from class "times" rather than "type".
  4034 INCOMPATIBILITY.
  4035 
  4036 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  4037 Linorder etc.  have disappeared; operations defined in terms of
  4038 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  4039 
  4040 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  4041 
  4042 * HOL-Word: New extensive library and type for generic, fixed size
  4043 machine words, with arithemtic, bit-wise, shifting and rotating
  4044 operations, reflection into int, nat, and bool lists, automation for
  4045 linear arithmetic (by automatic reflection into nat or int), including
  4046 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  4047 arithmetic type classes, supporting automatic simplification of
  4048 numerals on all operations.
  4049 
  4050 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  4051 
  4052 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  4053 
  4054 * Code generator library theories:
  4055   - Code_Integer represents HOL integers by big integer literals in target
  4056     languages.
  4057   - Code_Char represents HOL characters by character literals in target
  4058     languages.
  4059   - Code_Char_chr like Code_Char, but also offers treatment of character
  4060     codes; includes Code_Integer.
  4061   - Executable_Set allows to generate code for finite sets using lists.
  4062   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  4063     denominator).
  4064   - Executable_Real implements a subset of real numbers, namly those
  4065     representable by rational numbers.
  4066   - Efficient_Nat implements natural numbers by integers, which in general will
  4067     result in higher efficency; pattern matching with 0/Suc is eliminated;
  4068     includes Code_Integer.
  4069   - Code_Index provides an additional datatype index which is mapped to
  4070     target-language built-in integers.
  4071   - Code_Message provides an additional datatype message_string which is isomorphic to
  4072     strings; messages are mapped to target-language strings.
  4073 
  4074 * New package for inductive predicates
  4075 
  4076   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  4077 
  4078     inductive
  4079       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4080       for z_1 :: U_1 and ... and z_n :: U_m
  4081     where
  4082       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4083     | ...
  4084 
  4085   with full support for type-inference, rather than
  4086 
  4087     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4088 
  4089     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4090     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4091 
  4092     inductive "s z_1 ... z_m"
  4093     intros
  4094       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4095       ...
  4096 
  4097   For backward compatibility, there is a wrapper allowing inductive
  4098   sets to be defined with the new package via
  4099 
  4100     inductive_set
  4101       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4102       for z_1 :: U_1 and ... and z_n :: U_m
  4103     where
  4104       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4105     | ...
  4106 
  4107   or
  4108 
  4109     inductive_set
  4110       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4111       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4112       for z_1 :: U_1 and ... and z_n :: U_m
  4113     where
  4114       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4115     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4116     | ...
  4117 
  4118   if the additional syntax "p ..." is required.
  4119 
  4120   Numerous examples can be found in the subdirectories src/HOL/Auth,
  4121   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  4122 
  4123   INCOMPATIBILITIES:
  4124 
  4125   - Since declaration and definition of inductive sets or predicates
  4126     is no longer separated, abbreviations involving the newly
  4127     introduced sets or predicates must be specified together with the
  4128     introduction rules after the 'where' keyword (see above), rather
  4129     than before the actual inductive definition.
  4130 
  4131   - The variables in induction and elimination rules are now
  4132     quantified in the order of their occurrence in the introduction
  4133     rules, rather than in alphabetical order. Since this may break
  4134     some proofs, these proofs either have to be repaired, e.g. by
  4135     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  4136     statements of the form
  4137 
  4138       case (rule_i a_i_1 ... a_i_{k_i})
  4139 
  4140     or the old order of quantification has to be restored by explicitly adding
  4141     meta-level quantifiers in the introduction rules, i.e.
  4142 
  4143       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  4144 
  4145   - The format of the elimination rules is now
  4146 
  4147       p z_1 ... z_m x_1 ... x_n ==>
  4148         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4149         ==> ... ==> P
  4150 
  4151     for predicates and
  4152 
  4153       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4154         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4155         ==> ... ==> P
  4156 
  4157     for sets rather than
  4158 
  4159       x : s z_1 ... z_m ==>
  4160         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4161         ==> ... ==> P
  4162 
  4163     This may require terms in goals to be expanded to n-tuples
  4164     (e.g. using case_tac or simplification with the split_paired_all
  4165     rule) before the above elimination rule is applicable.
  4166 
  4167   - The elimination or case analysis rules for (mutually) inductive
  4168     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4169     list of rules "p_1_..._p_k.elims" is no longer available.
  4170 
  4171 * New package "function"/"fun" for general recursive functions,
  4172 supporting mutual and nested recursion, definitions in local contexts,
  4173 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4174 for small examples, and the separate tutorial on the function
  4175 package. The old recdef "package" is still available as before, but
  4176 users are encouraged to use the new package.
  4177 
  4178 * Method "lexicographic_order" automatically synthesizes termination
  4179 relations as lexicographic combinations of size measures. 
  4180 
  4181 * Case-expressions allow arbitrary constructor-patterns (including
  4182 "_") and take their order into account, like in functional
  4183 programming.  Internally, this is translated into nested
  4184 case-expressions; missing cases are added and mapped to the predefined
  4185 constant "undefined". In complicated cases printing may no longer show
  4186 the original input but the internal form. Lambda-abstractions allow
  4187 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4188 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4189 variable.
  4190 
  4191 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4192 is an abbreviation for "of_nat :: nat => int". The simplification
  4193 rules for "of_nat" have been changed to work like "int" did
  4194 previously.  Potential INCOMPATIBILITY:
  4195   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4196   - of_nat_diff and of_nat_mult are no longer default simp rules
  4197 
  4198 * Method "algebra" solves polynomial equations over (semi)rings using
  4199 Groebner bases. The (semi)ring structure is defined by locales and the
  4200 tool setup depends on that generic context. Installing the method for
  4201 a specific type involves instantiating the locale and possibly adding
  4202 declarations for computation on the coefficients.  The method is
  4203 already instantiated for natural numbers and for the axiomatic class
  4204 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4205 CALCULEMUS 2007 for the general principles underlying this
  4206 architecture of context-aware proof-tools.
  4207 
  4208 * Method "ferrack" implements quantifier elimination over
  4209 special-purpose dense linear orders using locales (analogous to
  4210 "algebra"). The method is already installed for class
  4211 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4212 rat, etc.
  4213 
  4214 * Former constant "List.op @" now named "List.append".  Use ML
  4215 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4216 circumvent possible incompatibilities when working on ML level.
  4217 
  4218 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4219 
  4220 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4221 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4222 
  4223 * New syntax for Haskell-like list comprehension (input only), eg.
  4224 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4225 
  4226 * The special syntax for function "filter" has changed from [x :
  4227 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4228 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4229 
  4230 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4231 defined on nat only, as an abbreviation for [a..<Suc b]
  4232 INCOMPATIBILITY.
  4233 
  4234 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4235 
  4236 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4237 
  4238 * New lemma collection field_simps (an extension of ring_simps) for
  4239 manipulating (in)equations involving division. Multiplies with all
  4240 denominators that can be proved to be non-zero (in equations) or
  4241 positive/negative (in inequations).
  4242 
  4243 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4244 have been improved and renamed to ring_simps, group_simps and
  4245 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4246 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4247 
  4248 * Theory Library/Commutative_Ring: switched from recdef to function
  4249 package; constants add, mul, pow now curried.  Infix syntax for
  4250 algebraic operations.
  4251 
  4252 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4253 INCOMPATIBILITY.
  4254 
  4255 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4256 INCOMPATIBILITY.
  4257 
  4258 * HOL/records: generalised field-update to take a function on the
  4259 field rather than the new value: r(|A := x|) is translated to A_update
  4260 (K x) r The K-combinator that is internally used is called K_record.
  4261 INCOMPATIBILITY: Usage of the plain update functions has to be
  4262 adapted.
  4263  
  4264 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4265 * x = 0, which are required for a semiring.  Richer structures do not
  4266 inherit from semiring_0 anymore, because this property is a theorem
  4267 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4268 there is more to prove, but this is mostly trivial.
  4269 
  4270 * Class "recpower" is generalized to arbitrary monoids, not just
  4271 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4272 commutativity or semiring properties additionally.
  4273 
  4274 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4275 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4276 better use 'abbreviation'.
  4277 
  4278 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4279 
  4280 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4281 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4282 significant changes for setting up numeral syntax for types:
  4283   - New constants Numeral.pred and Numeral.succ instead
  4284       of former Numeral.bin_pred and Numeral.bin_succ.
  4285   - Use integer operations instead of bin_add, bin_mult and so on.
  4286   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4287   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4288 
  4289 See src/HOL/Integ/IntArith.thy for an example setup.
  4290 
  4291 * Command 'normal_form' computes the normal form of a term that may
  4292 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4293 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4294 heavy-duty computations because the functions are compiled to ML
  4295 first.  Correspondingly, a method "normalization" is provided.  See
  4296 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4297 
  4298 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4299 25 like -->); output depends on the "iff" print_mode, the default is
  4300 "A = B" (with priority 50).
  4301 
  4302 * Relations less (<) and less_eq (<=) are also available on type bool.
  4303 Modified syntax to disallow nesting without explicit parentheses,
  4304 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4305 INCOMPATIBILITY.
  4306 
  4307 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4308 
  4309 * Relation composition operator "op O" now has precedence 75 and binds
  4310 stronger than union and intersection. INCOMPATIBILITY.
  4311 
  4312 * The old set interval syntax "{m..n(}" (and relatives) has been
  4313 removed.  Use "{m..<n}" (and relatives) instead.
  4314 
  4315 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4316 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4317 ``declare [[simproc del: neq]]''.
  4318 
  4319 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4320 True/False.
  4321 
  4322 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4323 
  4324 * Theorem setsum_mult renamed to setsum_right_distrib.
  4325 
  4326 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4327 ``rule'' method.
  4328 
  4329 * Reimplemented methods "sat" and "satx", with several improvements:
  4330 goals no longer need to be stated as "<prems> ==> False", equivalences
  4331 (i.e. "=" on type bool) are handled, variable names of the form
  4332 "lit_<n>" are no longer reserved, significant speedup.
  4333 
  4334 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4335 zChaff is still supported as well.
  4336 
  4337 * 'inductive' and 'datatype': provide projections of mutual rules,
  4338 bundled as foo_bar.inducts;
  4339 
  4340 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4341 Library.
  4342 
  4343 * Library: moved theory Accessible_Part to main HOL.
  4344 
  4345 * Library: added theory Coinductive_List of potentially infinite lists
  4346 as greatest fixed-point.
  4347 
  4348 * Library: added theory AssocList which implements (finite) maps as
  4349 association lists.
  4350 
  4351 * Method "evaluation" solves goals (i.e. a boolean expression)
  4352 efficiently by compiling it to ML.  The goal is "proved" (via an
  4353 oracle) if it evaluates to True.
  4354 
  4355 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4356 also when invoked by the simplifier.  This results in the Simplifier
  4357 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4358 Configuration option fast_arith_split_limit=0 recovers the old
  4359 behavior.
  4360 
  4361 * Support for hex (0x20) and binary (0b1001) numerals.
  4362 
  4363 * New method: reify eqs (t), where eqs are equations for an
  4364 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4365 parameter, computes a term s::'b and a list xs::'a list and proves the
  4366 theorem I xs s = t. This is also known as reification or quoting. The
  4367 resulting theorem is applied to the subgoal to substitute t with I xs
  4368 s.  If t is omitted, the subgoal itself is reified.
  4369 
  4370 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4371 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4372 where f is supposed to be a computable function (in the sense of code
  4373 generattion). The method uses reify to compute s and xs as above then
  4374 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4375 r and finally gets the theorem t = r, which is again applied to the
  4376 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4377 
  4378 * Reflection: Automatic reification now handels binding, an example is
  4379 available in src/HOL/ex/ReflectionEx.thy
  4380 
  4381 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4382 command 'statespace' that is similar to 'record', but introduces an
  4383 abstract specification based on the locale infrastructure instead of
  4384 HOL types.  This leads to extra flexibility in composing state spaces,
  4385 in particular multiple inheritance and renaming of components.
  4386 
  4387 
  4388 *** HOL-Complex ***
  4389 
  4390 * Hyperreal: Functions root and sqrt are now defined on negative real
  4391 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4392 Nonnegativity side conditions have been removed from many lemmas, so
  4393 that more subgoals may now be solved by simplification; potential
  4394 INCOMPATIBILITY.
  4395 
  4396 * Real: new type classes formalize real normed vector spaces and
  4397 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4398 and norm :: 'a => real.
  4399 
  4400 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4401 reals into other types. The overloaded constant Reals :: 'a set is now
  4402 defined as range of_real; potential INCOMPATIBILITY.
  4403 
  4404 * Real: proper support for ML code generation, including 'quickcheck'.
  4405 Reals are implemented as arbitrary precision rationals.
  4406 
  4407 * Hyperreal: Several constants that previously worked only for the
  4408 reals have been generalized, so they now work over arbitrary vector
  4409 spaces. Type annotations may need to be added in some cases; potential
  4410 INCOMPATIBILITY.
  4411 
  4412   Infinitesimal  :: ('a::real_normed_vector) star set
  4413   HFinite        :: ('a::real_normed_vector) star set
  4414   HInfinite      :: ('a::real_normed_vector) star set
  4415   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4416   monad          :: ('a::real_normed_vector) star => 'a star set
  4417   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4418   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4419   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4420   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4421   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4422   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4423   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4424   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4425   sgn            :: 'a::real_normed_vector => 'a
  4426   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4427 
  4428 * Complex: Some complex-specific constants are now abbreviations for
  4429 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4430 hnorm.  Other constants have been entirely removed in favor of the
  4431 polymorphic versions (INCOMPATIBILITY):
  4432 
  4433   approx        <-- capprox
  4434   HFinite       <-- CFinite
  4435   HInfinite     <-- CInfinite
  4436   Infinitesimal <-- CInfinitesimal
  4437   monad         <-- cmonad
  4438   galaxy        <-- cgalaxy
  4439   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4440   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4441   (ns)deriv     <-- (ns)cderiv
  4442 
  4443 
  4444 *** HOL-Algebra ***
  4445 
  4446 * Formalisation of ideals and the quotient construction over rings.
  4447 
  4448 * Order and lattice theory no longer based on records.
  4449 INCOMPATIBILITY.
  4450 
  4451 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4452 greatest_closed.  INCOMPATIBILITY.
  4453 
  4454 * Method algebra is now set up via an attribute.  For examples see
  4455 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4456 of algebraic structures.
  4457 
  4458 * Renamed theory CRing to Ring.
  4459 
  4460 
  4461 *** HOL-Nominal ***
  4462 
  4463 * Substantial, yet incomplete support for nominal datatypes (binding
  4464 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4465 src/HOL/Nominal/Examples.  Prospective users should consult
  4466 http://isabelle.in.tum.de/nominal/
  4467 
  4468 
  4469 *** ML ***
  4470 
  4471 * ML basics: just one true type int, which coincides with IntInf.int
  4472 (even on SML/NJ).
  4473 
  4474 * ML within Isar: antiquotations allow to embed statically-checked
  4475 formal entities in the source, referring to the context available at
  4476 compile-time.  For example:
  4477 
  4478 ML {* @{sort "{zero,one}"} *}
  4479 ML {* @{typ "'a => 'b"} *}
  4480 ML {* @{term "%x. x"} *}
  4481 ML {* @{prop "x == y"} *}
  4482 ML {* @{ctyp "'a => 'b"} *}
  4483 ML {* @{cterm "%x. x"} *}
  4484 ML {* @{cprop "x == y"} *}
  4485 ML {* @{thm asm_rl} *}
  4486 ML {* @{thms asm_rl} *}
  4487 ML {* @{type_name c} *}
  4488 ML {* @{type_syntax c} *}
  4489 ML {* @{const_name c} *}
  4490 ML {* @{const_syntax c} *}
  4491 ML {* @{context} *}
  4492 ML {* @{theory} *}
  4493 ML {* @{theory Pure} *}
  4494 ML {* @{theory_ref} *}
  4495 ML {* @{theory_ref Pure} *}
  4496 ML {* @{simpset} *}
  4497 ML {* @{claset} *}
  4498 ML {* @{clasimpset} *}
  4499 
  4500 The same works for sources being ``used'' within an Isar context.
  4501 
  4502 * ML in Isar: improved error reporting; extra verbosity with
  4503 ML_Context.trace enabled.
  4504 
  4505 * Pure/General/table.ML: the join operations now works via exceptions
  4506 DUP/SAME instead of type option. This is simpler in simple cases, and
  4507 admits slightly more efficient complex applications.
  4508 
  4509 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4510 use Context.generic instead of just theory.
  4511 
  4512 * Pure: datatype Context.generic joins theory/Proof.context and
  4513 provides some facilities for code that works in either kind of
  4514 context, notably GenericDataFun for uniform theory and proof data.
  4515 
  4516 * Pure: simplified internal attribute type, which is now always
  4517 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4518 local (Proof.context) attributes have been discontinued, while
  4519 minimizing code duplication. Thm.rule_attribute and
  4520 Thm.declaration_attribute build canonical attributes; see also structure
  4521 Context for further operations on Context.generic, notably
  4522 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4523 declarations and definitions.
  4524 
  4525 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4526 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4527 init only required for impure data. INCOMPATIBILITY: empty really need
  4528 to be empty (no dependencies on theory content!)
  4529 
  4530 * Pure/kernel: consts certification ignores sort constraints given in
  4531 signature declarations. (This information is not relevant to the
  4532 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4533 potential INCOMPATIBILITY.
  4534 
  4535 * Pure: axiomatic type classes are now purely definitional, with
  4536 explicit proofs of class axioms and super class relations performed
  4537 internally. See Pure/axclass.ML for the main internal interfaces --
  4538 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4539 AxClass.axiomatize_class/classrel/arity supersede
  4540 Sign.add_classes/classrel/arities.
  4541 
  4542 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4543 global/local versions on theory vs. Proof.context have been
  4544 discontinued; Attrib.syntax and Method.syntax have been adapted
  4545 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4546 attributes, methods, etc.
  4547 
  4548 * Pure: several functions of signature "... -> theory -> theory * ..."
  4549 have been reoriented to "... -> theory -> ... * theory" in order to
  4550 allow natural usage in combination with the ||>, ||>>, |-> and
  4551 fold_map combinators.
  4552 
  4553 * Pure: official theorem names (closed derivations) and additional
  4554 comments (tags) are now strictly separate.  Name hints -- which are
  4555 maintained as tags -- may be attached any time without affecting the
  4556 derivation.
  4557 
  4558 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4559 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4560 achieve the old behaviour.
  4561 
  4562 * Pure: the "Goal" constant is now called "prop", supporting a
  4563 slightly more general idea of ``protecting'' meta-level rule
  4564 statements.
  4565 
  4566 * Pure: Logic.(un)varify only works in a global context, which is now
  4567 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4568 Logic.legacy_(un)varify as temporary workaround.
  4569 
  4570 * Pure: structure Name provides scalable operations for generating
  4571 internal variable names, notably Name.variants etc.  This replaces
  4572 some popular functions from term.ML:
  4573 
  4574   Term.variant		->  Name.variant
  4575   Term.variantlist	->  Name.variant_list
  4576   Term.invent_names	->  Name.invent_list
  4577 
  4578 Note that low-level renaming rarely occurs in new code -- operations
  4579 from structure Variable are used instead (see below).
  4580 
  4581 * Pure: structure Variable provides fundamental operations for proper
  4582 treatment of fixed/schematic variables in a context.  For example,
  4583 Variable.import introduces fixes for schematics of given facts and
  4584 Variable.export reverses the effect (up to renaming) -- this replaces
  4585 various freeze_thaw operations.
  4586 
  4587 * Pure: structure Goal provides simple interfaces for
  4588 init/conclude/finish and tactical prove operations (replacing former
  4589 Tactic.prove).  Goal.prove is the canonical way to prove results
  4590 within a given context; Goal.prove_global is a degraded version for
  4591 theory level goals, including a global Drule.standard.  Note that
  4592 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4593 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4594 in a locale context).
  4595 
  4596 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4597 and type checking (Syntax.check_term etc.), with common combinations
  4598 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4599 which are considered legacy and await removal.
  4600 
  4601 * Pure/Syntax: generic interfaces for type unchecking
  4602 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4603 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4604 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4605 available for convenience, but refer to the very same operations using
  4606 a mere theory instead of a full context.
  4607 
  4608 * Isar: simplified treatment of user-level errors, using exception
  4609 ERROR of string uniformly.  Function error now merely raises ERROR,
  4610 without any side effect on output channels.  The Isar toplevel takes
  4611 care of proper display of ERROR exceptions.  ML code may use plain
  4612 handle/can/try; cat_error may be used to concatenate errors like this:
  4613 
  4614   ... handle ERROR msg => cat_error msg "..."
  4615 
  4616 Toplevel ML code (run directly or through the Isar toplevel) may be
  4617 embedded into the Isar toplevel with exception display/debug like
  4618 this:
  4619 
  4620   Isar.toplevel (fn () => ...)
  4621 
  4622 INCOMPATIBILITY, removed special transform_error facilities, removed
  4623 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4624 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4625 -- use plain ERROR instead.
  4626 
  4627 * Isar: theory setup now has type (theory -> theory), instead of a
  4628 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4629 
  4630 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4631 ProofContext.debug/verbose flags.
  4632 
  4633 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4634 theory before entering a proof state.  Transactions now always see a
  4635 quasi-functional intermediate checkpoint, both in interactive and
  4636 batch mode.
  4637 
  4638 * Isar: simplified interfaces for outer syntax.  Renamed
  4639 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4640 OuterSyntax.add_parsers -- this functionality is now included in
  4641 OuterSyntax.command etc.  INCOMPATIBILITY.
  4642 
  4643 * Simplifier: the simpset of a running simplification process now
  4644 contains a proof context (cf. Simplifier.the_context), which is the
  4645 very context that the initial simpset has been retrieved from (by
  4646 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4647 (solver, looper etc.) may depend on arbitrary proof data.
  4648 
  4649 * Simplifier.inherit_context inherits the proof context (plus the
  4650 local bounds) of the current simplification process; any simproc
  4651 etc. that calls the Simplifier recursively should do this!  Removed
  4652 former Simplifier.inherit_bounds, which is already included here --
  4653 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4654 specify an explicit context using Simplifier.context/theory_context.
  4655 
  4656 * Simplifier/Classical Reasoner: more abstract interfaces
  4657 change_simpset/claset for modifying the simpset/claset reference of a
  4658 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4659 INCOMPATIBILITY.
  4660 
  4661 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4662 "Trueprop" etc.
  4663 
  4664 
  4665 *** System ***
  4666 
  4667 * settings: the default heap location within ISABELLE_HOME_USER now
  4668 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4669 Isabelle installations.
  4670 
  4671 * isabelle-process: option -S (secure mode) disables some critical
  4672 operations, notably runtime compilation and evaluation of ML source
  4673 code.
  4674 
  4675 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4676 
  4677 * Support for parallel execution, using native multicore support of
  4678 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4679 independent theories, according to the given theory header
  4680 specifications. The maximum number of worker threads is specified via
  4681 usedir option -M or the "max-threads" setting in Proof General. A
  4682 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4683 to 6 on a 8-core machine.  User-code needs to observe certain
  4684 guidelines for thread-safe programming, see appendix A in the Isar
  4685 Implementation manual.
  4686 
  4687 
  4688 
  4689 New in Isabelle2005 (October 2005)
  4690 ----------------------------------
  4691 
  4692 *** General ***
  4693 
  4694 * Theory headers: the new header syntax for Isar theories is
  4695 
  4696   theory <name>
  4697   imports <theory1> ... <theoryN>
  4698   uses <file1> ... <fileM>
  4699   begin
  4700 
  4701 where the 'uses' part is optional.  The previous syntax
  4702 
  4703   theory <name> = <theory1> + ... + <theoryN>:
  4704 
  4705 will disappear in the next release.  Use isatool fixheaders to convert
  4706 existing theory files.  Note that there is no change in ancient
  4707 non-Isar theories now, but these will disappear soon.
  4708 
  4709 * Theory loader: parent theories can now also be referred to via
  4710 relative and absolute paths.
  4711 
  4712 * Command 'find_theorems' searches for a list of criteria instead of a
  4713 list of constants. Known criteria are: intro, elim, dest, name:string,
  4714 simp:term, and any term. Criteria can be preceded by '-' to select
  4715 theorems that do not match. Intro, elim, dest select theorems that
  4716 match the current goal, name:s selects theorems whose fully qualified
  4717 name contain s, and simp:term selects all simplification rules whose
  4718 lhs match term.  Any other term is interpreted as pattern and selects
  4719 all theorems matching the pattern. Available in ProofGeneral under
  4720 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4721 
  4722   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4723 
  4724 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4725 matching the current goal as introduction rule and not having "HOL."
  4726 in their name (i.e. not being defined in theory HOL).
  4727 
  4728 * Command 'thms_containing' has been discontinued in favour of
  4729 'find_theorems'; INCOMPATIBILITY.
  4730 
  4731 * Communication with Proof General is now 8bit clean, which means that
  4732 Unicode text in UTF-8 encoding may be used within theory texts (both
  4733 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4734 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4735 
  4736   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4737   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4738 
  4739 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4740 Classical Reasoner.  Typical big applications run around 2 times
  4741 faster.
  4742 
  4743 
  4744 *** Document preparation ***
  4745 
  4746 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4747 of raw sources.  Only those symbols that do not require additional
  4748 LaTeX packages (depending on comments in isabellesym.sty) are
  4749 displayed properly, everything else is left verbatim.  isatool display
  4750 and isatool print are used as front ends (these are subject to the
  4751 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4752 
  4753 * Command tags control specific markup of certain regions of text,
  4754 notably folding and hiding.  Predefined tags include "theory" (for
  4755 theory begin and end), "proof" for proof commands, and "ML" for
  4756 commands involving ML code; the additional tags "visible" and
  4757 "invisible" are unused by default.  Users may give explicit tag
  4758 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4759 interpretation of tags is determined by the LaTeX job during document
  4760 preparation: see option -V of isatool usedir, or options -n and -t of
  4761 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4762 \isadroptag.
  4763 
  4764 Several document versions may be produced at the same time via isatool
  4765 usedir (the generated index.html will link all of them).  Typical
  4766 specifications include ''-V document=theory,proof,ML'' to present
  4767 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4768 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4769 these parts without any formal replacement text.  The Isabelle site
  4770 default settings produce ''document'' and ''outline'' versions as
  4771 specified above.
  4772 
  4773 * Several new antiquotations:
  4774 
  4775   @{term_type term} prints a term with its type annotated;
  4776 
  4777   @{typeof term} prints the type of a term;
  4778 
  4779   @{const const} is the same as @{term const}, but checks that the
  4780   argument is a known logical constant;
  4781 
  4782   @{term_style style term} and @{thm_style style thm} print a term or
  4783   theorem applying a "style" to it
  4784 
  4785   @{ML text}
  4786 
  4787 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4788 definitions, equations, inequations etc., 'concl' printing only the
  4789 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4790 to print the specified premise.  TermStyle.add_style provides an ML
  4791 interface for introducing further styles.  See also the "LaTeX Sugar"
  4792 document practical applications.  The ML antiquotation prints
  4793 type-checked ML expressions verbatim.
  4794 
  4795 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4796 and 'text' support optional locale specification '(in loc)', which
  4797 specifies the default context for interpreting antiquotations.  For
  4798 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4799 
  4800 * Option 'locale=NAME' of antiquotations specifies an alternative
  4801 context interpreting the subsequent argument.  For example: @{thm
  4802 [locale=lattice] inf_assoc}.
  4803 
  4804 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4805 a proof context.
  4806 
  4807 * Proper output of antiquotations for theory commands involving a
  4808 proof context (such as 'locale' or 'theorem (in loc) ...').
  4809 
  4810 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4811 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4812 
  4813 * isatool usedir: new option -C (default true) controls whether option
  4814 -D should include a copy of the original document directory; -C false
  4815 prevents unwanted effects such as copying of administrative CVS data.
  4816 
  4817 
  4818 *** Pure ***
  4819 
  4820 * Considerably improved version of 'constdefs' command.  Now performs
  4821 automatic type-inference of declared constants; additional support for
  4822 local structure declarations (cf. locales and HOL records), see also
  4823 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4824 sequential dependencies of definitions within a single 'constdefs'
  4825 section; moreover, the declared name needs to be an identifier.  If
  4826 all fails, consider to fall back on 'consts' and 'defs' separately.
  4827 
  4828 * Improved indexed syntax and implicit structures.  First of all,
  4829 indexed syntax provides a notational device for subscripted
  4830 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4831 expressions.  Secondly, in a local context with structure
  4832 declarations, number indexes \<^sub>n or the empty index (default
  4833 number 1) refer to a certain fixed variable implicitly; option
  4834 show_structs controls printing of implicit structures.  Typical
  4835 applications of these concepts involve record types and locales.
  4836 
  4837 * New command 'no_syntax' removes grammar declarations (and
  4838 translations) resulting from the given syntax specification, which is
  4839 interpreted in the same manner as for the 'syntax' command.
  4840 
  4841 * 'Advanced' translation functions (parse_translation etc.) may depend
  4842 on the signature of the theory context being presently used for
  4843 parsing/printing, see also isar-ref manual.
  4844 
  4845 * Improved 'oracle' command provides a type-safe interface to turn an
  4846 ML expression of type theory -> T -> term into a primitive rule of
  4847 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4848 is already included here); see also FOL/ex/IffExample.thy;
  4849 INCOMPATIBILITY.
  4850 
  4851 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4852 before); "cI" is no longer bound, use "c.intro" instead.
  4853 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4854 axclasses vs. locales.
  4855 
  4856 * Improved internal renaming of symbolic identifiers -- attach primes
  4857 instead of base 26 numbers.
  4858 
  4859 * New flag show_question_marks controls printing of leading question
  4860 marks in schematic variable names.
  4861 
  4862 * In schematic variable names, *any* symbol following \<^isub> or
  4863 \<^isup> is now treated as part of the base name.  For example, the
  4864 following works without printing of awkward ".0" indexes:
  4865 
  4866   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4867     by simp
  4868 
  4869 * Inner syntax includes (*(*nested*) comments*).
  4870 
  4871 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4872 annotations as "(00...)".
  4873 
  4874 * Clear separation of logical types and nonterminals, where the latter
  4875 may only occur in 'syntax' specifications or type abbreviations.
  4876 Before that distinction was only partially implemented via type class
  4877 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4878 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4879 exotic syntax specifications may require further adaption
  4880 (e.g. Cube/Cube.thy).
  4881 
  4882 * Removed obsolete type class "logic", use the top sort {} instead.
  4883 Note that non-logical types should be declared as 'nonterminals'
  4884 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4885 specifications.
  4886 
  4887 * Attributes 'induct' and 'cases': type or set names may now be
  4888 locally fixed variables as well.
  4889 
  4890 * Simplifier: can now control the depth to which conditional rewriting
  4891 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4892 Limit.
  4893 
  4894 * Simplifier: simplification procedures may now take the current
  4895 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4896 interface), which is very useful for calling the Simplifier
  4897 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4898 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4899 low-level mk_simproc no longer applies Logic.varify internally, to
  4900 allow for use in a context of fixed variables.
  4901 
  4902 * thin_tac now works even if the assumption being deleted contains !!
  4903 or ==>.  More generally, erule now works even if the major premise of
  4904 the elimination rule contains !! or ==>.
  4905 
  4906 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4907 
  4908 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4909 from Pure, which contains all common declarations already.  Both
  4910 theories are defined via plain Isabelle/Isar .thy files.
  4911 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4912 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4913 use isatool fixcpure to adapt your theory and ML sources.
  4914 
  4915 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4916 selections of theorems in named facts via index ranges.
  4917 
  4918 * 'print_theorems': in theory mode, really print the difference
  4919 wrt. the last state (works for interactive theory development only),
  4920 in proof mode print all local facts (cf. 'print_facts');
  4921 
  4922 * 'hide': option '(open)' hides only base names.
  4923 
  4924 * More efficient treatment of intermediate checkpoints in interactive
  4925 theory development.
  4926 
  4927 * Code generator is now invoked via code_module (incremental code
  4928 generation) and code_library (modular code generation, ML structures
  4929 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4930 must be quoted when used as identifiers.
  4931 
  4932 * New 'value' command for reading, evaluating and printing terms using
  4933 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4934 quoted when used as identifier.
  4935 
  4936 
  4937 *** Locales ***
  4938 
  4939 * New commands for the interpretation of locale expressions in
  4940 theories (1), locales (2) and proof contexts (3).  These generate
  4941 proof obligations from the expression specification.  After the
  4942 obligations have been discharged, theorems of the expression are added
  4943 to the theory, target locale or proof context.  The synopsis of the
  4944 commands is a follows:
  4945 
  4946   (1) interpretation expr inst
  4947   (2) interpretation target < expr
  4948   (3) interpret expr inst
  4949 
  4950 Interpretation in theories and proof contexts require a parameter
  4951 instantiation of terms from the current context.  This is applied to
  4952 specifications and theorems of the interpreted expression.
  4953 Interpretation in locales only permits parameter renaming through the
  4954 locale expression.  Interpretation is smart in that interpretations
  4955 that are active already do not occur in proof obligations, neither are
  4956 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4957 inspect active interpretations of a particular locale.  For details,
  4958 see the Isar Reference manual.  Examples can be found in
  4959 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4960 
  4961 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4962 'interpret' instead.
  4963 
  4964 * New context element 'constrains' for adding type constraints to
  4965 parameters.
  4966 
  4967 * Context expressions: renaming of parameters with syntax
  4968 redeclaration.
  4969 
  4970 * Locale declaration: 'includes' disallowed.
  4971 
  4972 * Proper static binding of attribute syntax -- i.e. types / terms /
  4973 facts mentioned as arguments are always those of the locale definition
  4974 context, independently of the context of later invocations.  Moreover,
  4975 locale operations (renaming and type / term instantiation) are applied
  4976 to attribute arguments as expected.
  4977 
  4978 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4979 actual attributes; rare situations may require Attrib.attribute to
  4980 embed those attributes into Attrib.src that lack concrete syntax.
  4981 Attribute implementations need to cooperate properly with the static
  4982 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4983 Attrib.XXX_thm etc. already do the right thing without further
  4984 intervention.  Only unusual applications -- such as "where" or "of"
  4985 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4986 on the context and the facts involved -- may have to assign parsed
  4987 values to argument tokens explicitly.
  4988 
  4989 * Changed parameter management in theorem generation for long goal
  4990 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4991 theorem statement in rare situations.
  4992 
  4993 * Locale inspection command 'print_locale' omits notes elements.  Use
  4994 'print_locale!' to have them included in the output.
  4995 
  4996 
  4997 *** Provers ***
  4998 
  4999 * Provers/hypsubst.ML: improved version of the subst method, for
  5000 single-step rewriting: it now works in bound variable contexts. New is
  5001 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  5002 rewrite a different subterm than the original subst method, which is
  5003 still available as 'simplesubst'.
  5004 
  5005 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  5006 and quasi orders.
  5007 
  5008 * Provers/trancl.ML: new transitivity reasoner for transitive and
  5009 reflexive-transitive closure of relations.
  5010 
  5011 * Provers/blast.ML: new reference depth_limit to make blast's depth
  5012 limit (previously hard-coded with a value of 20) user-definable.
  5013 
  5014 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  5015 is peformed already.  Object-logics merely need to finish their
  5016 initial simpset configuration as before.  INCOMPATIBILITY.
  5017 
  5018 
  5019 *** HOL ***
  5020 
  5021 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  5022 
  5023   syntax (epsilon)
  5024     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  5025 
  5026 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  5027 and x-symbol; use option '-m epsilon' to get it actually printed.
  5028 Moreover, the mathematically important symbolic identifier \<epsilon>
  5029 becomes available as variable, constant etc.  INCOMPATIBILITY,
  5030 
  5031 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  5032 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  5033 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  5034 support corresponding Isar calculations.
  5035 
  5036 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  5037 instead of ":".
  5038 
  5039 * theory SetInterval: changed the syntax for open intervals:
  5040 
  5041   Old       New
  5042   {..n(}    {..<n}
  5043   {)n..}    {n<..}
  5044   {m..n(}   {m..<n}
  5045   {)m..n}   {m<..n}
  5046   {)m..n(}  {m<..<n}
  5047 
  5048 The old syntax is still supported but will disappear in the next
  5049 release.  For conversion use the following Emacs search and replace
  5050 patterns (these are not perfect but work quite well):
  5051 
  5052   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  5053   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  5054 
  5055 * Theory Commutative_Ring (in Library): method comm_ring for proving
  5056 equalities in commutative rings; method 'algebra' provides a generic
  5057 interface.
  5058 
  5059 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  5060 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  5061 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  5062 be a tuple pattern.
  5063 
  5064 Some new syntax forms are available:
  5065 
  5066   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  5067   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  5068   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  5069   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  5070 
  5071 The latter form "\<Sum>x < k. e" used to be based on a separate
  5072 function "Summation", which has been discontinued.
  5073 
  5074 * theory Finite_Set: in structured induction proofs, the insert case
  5075 is now 'case (insert x F)' instead of the old counterintuitive 'case
  5076 (insert F x)'.
  5077 
  5078 * The 'refute' command has been extended to support a much larger
  5079 fragment of HOL, including axiomatic type classes, constdefs and
  5080 typedefs, inductive datatypes and recursion.
  5081 
  5082 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  5083 Requires zChaff with proof generation to be installed.  See
  5084 HOL/ex/SAT_Examples.thy for examples.
  5085 
  5086 * Datatype induction via method 'induct' now preserves the name of the
  5087 induction variable. For example, when proving P(xs::'a list) by
  5088 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  5089 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  5090 in unstructured proof scripts.
  5091 
  5092 * Reworked implementation of records.  Improved scalability for
  5093 records with many fields, avoiding performance problems for type
  5094 inference. Records are no longer composed of nested field types, but
  5095 of nested extension types. Therefore the record type only grows linear
  5096 in the number of extensions and not in the number of fields.  The
  5097 top-level (users) view on records is preserved.  Potential
  5098 INCOMPATIBILITY only in strange cases, where the theory depends on the
  5099 old record representation. The type generated for a record is called
  5100 <record_name>_ext_type.
  5101 
  5102 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  5103 proofs triggered by a record definition or a simproc (if
  5104 quick_and_dirty is enabled).  Definitions of large records can take
  5105 quite long.
  5106 
  5107 New simproc record_upd_simproc for simplification of multiple record
  5108 updates enabled by default.  Moreover, trivial updates are also
  5109 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  5110 occasionally, since simplification is more powerful by default.
  5111 
  5112 * typedef: proper support for polymorphic sets, which contain extra
  5113 type-variables in the term.
  5114 
  5115 * Simplifier: automatically reasons about transitivity chains
  5116 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  5117 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  5118 old proofs break occasionally as simplification may now solve more
  5119 goals than previously.
  5120 
  5121 * Simplifier: converts x <= y into x = y if assumption y <= x is
  5122 present.  Works for all partial orders (class "order"), in particular
  5123 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  5124 just like y <= x.
  5125 
  5126 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  5127 bound variable or a constant then the let is unfolded.  Otherwise
  5128 first a is simplified to b, and then f b is simplified to g. If
  5129 possible we abstract b from g arriving at "let x = b in h x",
  5130 otherwise we unfold the let and arrive at g.  The simproc can be
  5131 enabled/disabled by the reference use_let_simproc.  Potential
  5132 INCOMPATIBILITY since simplification is more powerful by default.
  5133 
  5134 * Classical reasoning: the meson method now accepts theorems as arguments.
  5135 
  5136 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  5137 jobs to provide advice on the provability of subgoals.
  5138 
  5139 * Theory OrderedGroup and Ring_and_Field: various additions and
  5140 improvements to faciliate calculations involving equalities and
  5141 inequalities.
  5142 
  5143 The following theorems have been eliminated or modified
  5144 (INCOMPATIBILITY):
  5145 
  5146   abs_eq             now named abs_of_nonneg
  5147   abs_of_ge_0        now named abs_of_nonneg
  5148   abs_minus_eq       now named abs_of_nonpos
  5149   imp_abs_id         now named abs_of_nonneg
  5150   imp_abs_neg_id     now named abs_of_nonpos
  5151   mult_pos           now named mult_pos_pos
  5152   mult_pos_le        now named mult_nonneg_nonneg
  5153   mult_pos_neg_le    now named mult_nonneg_nonpos
  5154   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5155   mult_neg           now named mult_neg_neg
  5156   mult_neg_le        now named mult_nonpos_nonpos
  5157 
  5158 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5159      
  5160      zero_le_square
  5161      not_square_less_zero 
  5162 
  5163   The following lemmas have been deleted from Real/RealPow:
  5164   
  5165      realpow_zero_zero
  5166      realpow_two
  5167      realpow_less
  5168      zero_le_power
  5169      realpow_two_le
  5170      abs_realpow_two
  5171      realpow_two_abs     
  5172 
  5173 * Theory Parity: added rules for simplifying exponents.
  5174 
  5175 * Theory List:
  5176 
  5177 The following theorems have been eliminated or modified
  5178 (INCOMPATIBILITY):
  5179 
  5180   list_all_Nil       now named list_all.simps(1)
  5181   list_all_Cons      now named list_all.simps(2)
  5182   list_all_conv      now named list_all_iff
  5183   set_mem_eq         now named mem_iff
  5184 
  5185 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5186 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5187 
  5188 
  5189 *** HOL-Complex ***
  5190 
  5191 * Theory RealDef: better support for embedding natural numbers and
  5192 integers in the reals.
  5193 
  5194 The following theorems have been eliminated or modified
  5195 (INCOMPATIBILITY):
  5196 
  5197   exp_ge_add_one_self  now requires no hypotheses
  5198   real_of_int_add      reversed direction of equality (use [symmetric])
  5199   real_of_int_minus    reversed direction of equality (use [symmetric])
  5200   real_of_int_diff     reversed direction of equality (use [symmetric])
  5201   real_of_int_mult     reversed direction of equality (use [symmetric])
  5202 
  5203 * Theory RComplete: expanded support for floor and ceiling functions.
  5204 
  5205 * Theory Ln is new, with properties of the natural logarithm
  5206 
  5207 * Hyperreal: There is a new type constructor "star" for making
  5208 nonstandard types.  The old type names are now type synonyms:
  5209 
  5210   hypreal = real star
  5211   hypnat = nat star
  5212   hcomplex = complex star
  5213 
  5214 * Hyperreal: Many groups of similarly-defined constants have been
  5215 replaced by polymorphic versions (INCOMPATIBILITY):
  5216 
  5217   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5218 
  5219   starset      <-- starsetNat, starsetC
  5220   *s*          <-- *sNat*, *sc*
  5221   starset_n    <-- starsetNat_n, starsetC_n
  5222   *sn*         <-- *sNatn*, *scn*
  5223   InternalSets <-- InternalNatSets, InternalCSets
  5224 
  5225   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5226   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5227   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5228   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5229   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5230 
  5231 * Hyperreal: Many type-specific theorems have been removed in favor of
  5232 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5233 
  5234   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5235   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5236   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5237   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5238   right_minus <-- hypreal_add_minus
  5239   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5240   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5241   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5242   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5243   mult_1_right <-- hcomplex_mult_one_right
  5244   mult_zero_left <-- hcomplex_mult_zero_left
  5245   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5246   right_distrib <-- hypnat_add_mult_distrib2
  5247   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5248   right_inverse <-- hypreal_mult_inverse
  5249   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5250   order_refl <-- {hypreal,hypnat}_le_refl
  5251   order_trans <-- {hypreal,hypnat}_le_trans
  5252   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5253   order_less_le <-- {hypreal,hypnat}_less_le
  5254   linorder_linear <-- {hypreal,hypnat}_le_linear
  5255   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5256   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5257   add_nonneg_nonneg <-- hypreal_le_add_order
  5258 
  5259 * Hyperreal: Separate theorems having to do with type-specific
  5260 versions of constants have been merged into theorems that apply to the
  5261 new polymorphic constants (INCOMPATIBILITY):
  5262 
  5263   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5264   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5265   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5266   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5267   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5268   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5269   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5270   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5271   STAR_diff <-- {STAR,STARC}_diff
  5272   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5273     STARC_hcomplex_of_complex}_image_subset
  5274   starset_n_Un <-- starset{Nat,C}_n_Un
  5275   starset_n_Int <-- starset{Nat,C}_n_Int
  5276   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5277   starset_n_diff <-- starset{Nat,C}_n_diff
  5278   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5279   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5280   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5281   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5282   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5283   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5284   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5285   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5286   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5287   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5288   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5289   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5290   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5291   starfun_diff <-- starfun{C,RC,CR}_diff
  5292   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5293   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5294   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5295   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5296   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5297   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5298   starfun_Id <-- starfunC_Id
  5299   starfun_approx <-- starfun{Nat,CR}_approx
  5300   starfun_capprox <-- starfun{C,RC}_capprox
  5301   starfun_abs <-- starfunNat_rabs
  5302   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5303   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5304   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5305   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5306   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5307   starfun_add_approx <-- starfunCR_add_approx
  5308   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5309   starfun_divide <-- starfun{C,CR,RC}_divide
  5310   starfun_n <-- starfun{Nat,C}_n
  5311   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5312   starfun_n_add <-- starfun{Nat,C}_n_add
  5313   starfun_n_add_minus <-- starfunNat_n_add_minus
  5314   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5315   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5316   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5317 
  5318   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5319   star_n_minus <-- {hypreal,hcomplex}_minus
  5320   star_n_diff <-- {hypreal,hcomplex}_diff
  5321   star_n_mult <-- {hypreal,hcomplex}_mult
  5322   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5323   star_n_le <-- {hypreal,hypnat}_le
  5324   star_n_less <-- {hypreal,hypnat}_less
  5325   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5326   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5327   star_n_abs <-- hypreal_hrabs
  5328   star_n_divide <-- hcomplex_divide
  5329 
  5330   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5331   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5332   star_of_diff <-- hypreal_of_real_diff
  5333   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5334   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5335   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5336   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5337   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5338   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5339   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5340   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5341   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5342   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5343   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5344   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5345   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5346   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5347   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5348   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5349   star_of_power <-- hypreal_of_real_power
  5350   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5351 
  5352 * Hyperreal: new method "transfer" that implements the transfer
  5353 principle of nonstandard analysis. With a subgoal that mentions
  5354 nonstandard types like "'a star", the command "apply transfer"
  5355 replaces it with an equivalent one that mentions only standard types.
  5356 To be successful, all free variables must have standard types; non-
  5357 standard variables must have explicit universal quantifiers.
  5358 
  5359 * Hyperreal: A theory of Taylor series.
  5360 
  5361 
  5362 *** HOLCF ***
  5363 
  5364 * Discontinued special version of 'constdefs' (which used to support
  5365 continuous functions) in favor of the general Pure one with full
  5366 type-inference.
  5367 
  5368 * New simplification procedure for solving continuity conditions; it
  5369 is much faster on terms with many nested lambda abstractions (cubic
  5370 instead of exponential time).
  5371 
  5372 * New syntax for domain package: selector names are now optional.
  5373 Parentheses should be omitted unless argument is lazy, for example:
  5374 
  5375   domain 'a stream = cons "'a" (lazy "'a stream")
  5376 
  5377 * New command 'fixrec' for defining recursive functions with pattern
  5378 matching; defining multiple functions with mutual recursion is also
  5379 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5380 sinr, or any data constructor defined by the domain package. The given
  5381 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5382 syntax and examples.
  5383 
  5384 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5385 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5386 but the proof obligation additionally includes an admissibility
  5387 requirement. The packages generate instances of class cpo or pcpo,
  5388 with continuity and strictness theorems for Rep and Abs.
  5389 
  5390 * HOLCF: Many theorems have been renamed according to a more standard naming
  5391 scheme (INCOMPATIBILITY):
  5392 
  5393   foo_inject:  "foo$x = foo$y ==> x = y"
  5394   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5395   foo_less:    "(foo$x << foo$y) = (x << y)"
  5396   foo_strict:  "foo$UU = UU"
  5397   foo_defined: "... ==> foo$x ~= UU"
  5398   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5399 
  5400 
  5401 *** ZF ***
  5402 
  5403 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5404 including the First Isomorphism Theorem (on quotienting by the kernel
  5405 of a homomorphism).
  5406 
  5407 * ZF/Simplifier: install second copy of type solver that actually
  5408 makes use of TC rules declared to Isar proof contexts (or locales);
  5409 the old version is still required for ML proof scripts.
  5410 
  5411 
  5412 *** Cube ***
  5413 
  5414 * Converted to Isar theory format; use locales instead of axiomatic
  5415 theories.
  5416 
  5417 
  5418 *** ML ***
  5419 
  5420 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5421 for ||>, ||>>, |>>,
  5422 
  5423 * Pure/library.ML no longer defines its own option datatype, but uses
  5424 that of the SML basis, which has constructors NONE and SOME instead of
  5425 None and Some, as well as exception Option.Option instead of OPTION.
  5426 The functions the, if_none, is_some, is_none have been adapted
  5427 accordingly, while Option.map replaces apsome.
  5428 
  5429 * Pure/library.ML: the exception LIST has been given up in favour of
  5430 the standard exceptions Empty and Subscript, as well as
  5431 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5432 superceded by the standard hd and tl functions etc.
  5433 
  5434 A number of basic list functions are no longer exported to the ML
  5435 toplevel, as they are variants of predefined functions.  The following
  5436 suggests how one can translate existing code:
  5437 
  5438     rev_append xs ys = List.revAppend (xs, ys)
  5439     nth_elem (i, xs) = List.nth (xs, i)
  5440     last_elem xs = List.last xs
  5441     flat xss = List.concat xss
  5442     seq fs = List.app fs
  5443     partition P xs = List.partition P xs
  5444     mapfilter f xs = List.mapPartial f xs
  5445 
  5446 * Pure/library.ML: several combinators for linear functional
  5447 transformations, notably reverse application and composition:
  5448 
  5449   x |> f                f #> g
  5450   (x, y) |-> f          f #-> g
  5451 
  5452 * Pure/library.ML: introduced/changed precedence of infix operators:
  5453 
  5454   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5455   infix 2 ?;
  5456   infix 3 o oo ooo oooo;
  5457   infix 4 ~~ upto downto;
  5458 
  5459 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5460 infix operators.
  5461 
  5462 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5463 fold_map support linear functional transformations and nesting.  For
  5464 example:
  5465 
  5466   fold f [x1, ..., xN] y =
  5467     y |> f x1 |> ... |> f xN
  5468 
  5469   (fold o fold) f [xs1, ..., xsN] y =
  5470     y |> fold f xs1 |> ... |> fold f xsN
  5471 
  5472   fold f [x1, ..., xN] =
  5473     f x1 #> ... #> f xN
  5474 
  5475   (fold o fold) f [xs1, ..., xsN] =
  5476     fold f xs1 #> ... #> fold f xsN
  5477 
  5478 * Pure/library.ML: the following selectors on type 'a option are
  5479 available:
  5480 
  5481   the:               'a option -> 'a  (*partial*)
  5482   these:             'a option -> 'a  where 'a = 'b list
  5483   the_default: 'a -> 'a option -> 'a
  5484   the_list:          'a option -> 'a list
  5485 
  5486 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5487 basic operations for association lists, following natural argument
  5488 order; moreover the explicit equality predicate passed here avoids
  5489 potentially expensive polymorphic runtime equality checks.
  5490 The old functions may be expressed as follows:
  5491 
  5492   assoc = uncurry (AList.lookup (op =))
  5493   assocs = these oo AList.lookup (op =)
  5494   overwrite = uncurry (AList.update (op =)) o swap
  5495 
  5496 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5497 
  5498   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5499   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5500 
  5501 replacing make_keylist and keyfilter (occassionally used)
  5502 Naive rewrites:
  5503 
  5504   make_keylist = AList.make
  5505   keyfilter = AList.find (op =)
  5506 
  5507 * eq_fst and eq_snd now take explicit equality parameter, thus
  5508   avoiding eqtypes. Naive rewrites:
  5509 
  5510     eq_fst = eq_fst (op =)
  5511     eq_snd = eq_snd (op =)
  5512 
  5513 * Removed deprecated apl and apr (rarely used).
  5514   Naive rewrites:
  5515 
  5516     apl (n, op) =>>= curry op n
  5517     apr (op, m) =>>= fn n => op (n, m)
  5518 
  5519 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5520 provides a reasonably efficient light-weight implementation of sets as
  5521 lists.
  5522 
  5523 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5524 few new operations; existing lookup and update are now curried to
  5525 follow natural argument order (for use with fold etc.);
  5526 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5527 
  5528 * Pure/General: output via the Isabelle channels of
  5529 writeln/warning/error etc. is now passed through Output.output, with a
  5530 hook for arbitrary transformations depending on the print_mode
  5531 (cf. Output.add_mode -- the first active mode that provides a output
  5532 function wins).  Already formatted output may be embedded into further
  5533 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5534 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5535 accommodate easy composition of diagnostic messages etc.  Programmers
  5536 rarely need to care about Output.output or Output.raw at all, with
  5537 some notable exceptions: Output.output is required when bypassing the
  5538 standard channels (writeln etc.), or in token translations to produce
  5539 properly formatted results; Output.raw is required when capturing
  5540 already output material that will eventually be presented to the user
  5541 a second time.  For the default print mode, both Output.output and
  5542 Output.raw have no effect.
  5543 
  5544 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5545 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5546 cumulative results are displayed at the end of a batch session.
  5547 
  5548 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5549 replaced by File.platform_path and File.shell_path (with appropriate
  5550 hooks).  This provides a clean interface for unusual systems where the
  5551 internal and external process view of file names are different.
  5552 
  5553 * Pure: more efficient orders for basic syntactic entities: added
  5554 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5555 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5556 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5557 orders now -- potential INCOMPATIBILITY for code that depends on a
  5558 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5559 Library.sort_strings on result).
  5560 
  5561 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5562 fold_types traverse types/terms from left to right, observing natural
  5563 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5564 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5565 
  5566 * Pure: name spaces have been refined, with significant changes of the
  5567 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5568 to extern(_table).  The plain name entry path is superceded by a
  5569 general 'naming' context, which also includes the 'policy' to produce
  5570 a fully qualified name and external accesses of a fully qualified
  5571 name; NameSpace.extend is superceded by context dependent
  5572 Sign.declare_name.  Several theory and proof context operations modify
  5573 the naming context.  Especially note Theory.restore_naming and
  5574 ProofContext.restore_naming to get back to a sane state; note that
  5575 Theory.add_path is no longer sufficient to recover from
  5576 Theory.absolute_path in particular.
  5577 
  5578 * Pure: new flags short_names (default false) and unique_names
  5579 (default true) for controlling output of qualified names.  If
  5580 short_names is set, names are printed unqualified.  If unique_names is
  5581 reset, the name prefix is reduced to the minimum required to achieve
  5582 the original result when interning again, even if there is an overlap
  5583 with earlier declarations.
  5584 
  5585 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5586 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5587 (useful for printing error messages).  INCOMPATIBILITY.
  5588 
  5589 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5590 Theory.theory are now identified, referring to the universal
  5591 Context.theory (see Pure/context.ML).  Actual signature and theory
  5592 content is managed as theory data.  The old code and interfaces were
  5593 spread over many files and structures; the new arrangement introduces
  5594 considerable INCOMPATIBILITY to gain more clarity:
  5595 
  5596   Context -- theory management operations (name, identity, inclusion,
  5597     parents, ancestors, merge, etc.), plus generic theory data;
  5598 
  5599   Sign -- logical signature and syntax operations (declaring consts,
  5600     types, etc.), plus certify/read for common entities;
  5601 
  5602   Theory -- logical theory operations (stating axioms, definitions,
  5603     oracles), plus a copy of logical signature operations (consts,
  5604     types, etc.); also a few basic management operations (Theory.copy,
  5605     Theory.merge, etc.)
  5606 
  5607 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5608 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5609 for convenience -- they merely return the theory.
  5610 
  5611 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5612 
  5613 * Pure: the Isar proof context type is already defined early in Pure
  5614 as Context.proof (note that ProofContext.context and Proof.context are
  5615 aliases, where the latter is the preferred name).  This enables other
  5616 Isabelle components to refer to that type even before Isar is present.
  5617 
  5618 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5619 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5620 any of these kinds.  For example, Sign.intern typeK is now
  5621 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5622 Theory.hide_types.  Also note that former
  5623 Theory.hide_classes/types/consts are now
  5624 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5625 internalize their arguments!  INCOMPATIBILITY.
  5626 
  5627 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5628 datatype thmref (with constructors Name and NameSelection) instead of
  5629 plain string -- INCOMPATIBILITY;
  5630 
  5631 * Pure: cases produced by proof methods specify options, where NONE
  5632 means to remove case bindings -- INCOMPATIBILITY in
  5633 (RAW_)METHOD_CASES.
  5634 
  5635 * Pure: the following operations retrieve axioms or theorems from a
  5636 theory node or theory hierarchy, respectively:
  5637 
  5638   Theory.axioms_of: theory -> (string * term) list
  5639   Theory.all_axioms_of: theory -> (string * term) list
  5640   PureThy.thms_of: theory -> (string * thm) list
  5641   PureThy.all_thms_of: theory -> (string * thm) list
  5642 
  5643 * Pure: print_tac now outputs the goal through the trace channel.
  5644 
  5645 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5646 Reference Toplevel.debug (default false) controls detailed printing
  5647 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5648 controls execution profiling -- set to 1 for time and 2 for space
  5649 (both increase the runtime).
  5650 
  5651 * Isar session: The initial use of ROOT.ML is now always timed,
  5652 i.e. the log will show the actual process times, in contrast to the
  5653 elapsed wall-clock time that the outer shell wrapper produces.
  5654 
  5655 * Simplifier: improved handling of bound variables (nameless
  5656 representation, avoid allocating new strings).  Simprocs that invoke
  5657 the Simplifier recursively should use Simplifier.inherit_bounds to
  5658 avoid local name clashes.  Failure to do so produces warnings
  5659 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5660 for further details.
  5661 
  5662 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5663 bindings for all theorems stored within a given theory; this may help
  5664 in porting non-Isar theories to Isar ones, while keeping ML proof
  5665 scripts for the time being.
  5666 
  5667 * ML operator HTML.with_charset specifies the charset begin used for
  5668 generated HTML files.  For example:
  5669 
  5670   HTML.with_charset "utf-8" use_thy "Hebrew";
  5671   HTML.with_charset "utf-8" use_thy "Chinese";
  5672 
  5673 
  5674 *** System ***
  5675 
  5676 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5677 isabelle, isatool etc.).
  5678 
  5679 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5680 isatool doc, isatool mkdir, display_drafts etc.).
  5681 
  5682 * isatool usedir: option -f allows specification of the ML file to be
  5683 used by Isabelle; default is ROOT.ML.
  5684 
  5685 * New isatool version outputs the version identifier of the Isabelle
  5686 distribution being used.
  5687 
  5688 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5689 (containing Boolean satisfiability problems) into Isabelle/HOL
  5690 theories.
  5691 
  5692 
  5693 
  5694 New in Isabelle2004 (April 2004)
  5695 --------------------------------
  5696 
  5697 *** General ***
  5698 
  5699 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5700   Replaces linorder.ML.
  5701 
  5702 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5703   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5704   (\<a>...\<z>), are now considered normal letters, and can therefore
  5705   be used anywhere where an ASCII letter (a...zA...Z) has until
  5706   now. COMPATIBILITY: This obviously changes the parsing of some
  5707   terms, especially where a symbol has been used as a binder, say
  5708   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5709   as an identifier.  Fix it by inserting a space around former
  5710   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5711   existing theory and ML files.
  5712 
  5713 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5714 
  5715 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5716   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5717   a normal (but invisible) letter. For multiple letter subscripts repeat
  5718   \<^isub> like this: x\<^isub>1\<^isub>2.
  5719 
  5720 * Pure: There are now sub-/superscripts that can span more than one
  5721   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5722   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5723   superscript. The new control characters are not identifier parts.
  5724 
  5725 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5726   content of "..." to the latex file instead of \isacntrl... . The "..."
  5727   may consist of any printable characters excluding the end bracket >.
  5728 
  5729 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5730   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5731   declare constants "final", which prevents their being given a definition
  5732   later.  It is useful for constants whose behaviour is fixed axiomatically
  5733   rather than definitionally, such as the meta-logic connectives.
  5734 
  5735 * Pure: 'instance' now handles general arities with general sorts
  5736   (i.e. intersections of classes),
  5737 
  5738 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5739   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5740   It can be changed to alter the colors/layout of generated pages.
  5741 
  5742 
  5743 *** Isar ***
  5744 
  5745 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5746   cut_tac, subgoal_tac and thin_tac:
  5747   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5748     locales are no longer forced to write Isar proof scripts.
  5749     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5750     emulations.
  5751   - INCOMPATIBILITY: names of variables to be instantiated may no
  5752     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5753     This is consistent with the instantiation attribute "where".
  5754 
  5755 * Attributes "where" and "of":
  5756   - Now take type variables of instantiated theorem into account when reading
  5757     the instantiation string.  This fixes a bug that caused instantiated
  5758     theorems to have too special types in some circumstances.
  5759   - "where" permits explicit instantiations of type variables.
  5760 
  5761 * Calculation commands "moreover" and "also" no longer interfere with
  5762   current facts ("this"), admitting arbitrary combinations with "then"
  5763   and derived forms.
  5764 
  5765 * Locales:
  5766   - Goal statements involving the context element "includes" no longer
  5767     generate theorems with internal delta predicates (those ending on
  5768     "_axioms") in the premise.
  5769     Resolve particular premise with <locale>.intro to obtain old form.
  5770   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5771     specification and "includes" elements in goal statement.
  5772   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5773     [intro?] and [elim?] (respectively) by default.
  5774   - Experimental command for instantiation of locales in proof contexts:
  5775         instantiate <label>[<attrs>]: <loc>
  5776     Instantiates locale <loc> and adds all its theorems to the current context
  5777     taking into account their attributes.  Label and attrs are optional
  5778     modifiers, like in theorem declarations.  If present, names of
  5779     instantiated theorems are qualified with <label>, and the attributes
  5780     <attrs> are applied after any attributes these theorems might have already.
  5781       If the locale has assumptions, a chained fact of the form
  5782     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5783     are derived.  The command does not support old-style locales declared
  5784     with "locale (open)".
  5785       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5786 
  5787 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5788   (Isar) contexts.
  5789 
  5790 
  5791 *** HOL ***
  5792 
  5793 * Proof import: new image HOL4 contains the imported library from
  5794   the HOL4 system with about 2500 theorems. It is imported by
  5795   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5796   can be used like any other Isabelle image.  See
  5797   HOL/Import/HOL/README for more information.
  5798 
  5799 * Simplifier:
  5800   - Much improved handling of linear and partial orders.
  5801     Reasoners for linear and partial orders are set up for type classes
  5802     "linorder" and "order" respectively, and are added to the default simpset
  5803     as solvers.  This means that the simplifier can build transitivity chains
  5804     to solve goals from the assumptions.
  5805   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5806     of blast or auto after simplification become unnecessary because the goal
  5807     is solved by simplification already.
  5808 
  5809 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5810     all proved in axiomatic type classes for semirings, rings and fields.
  5811 
  5812 * Numerics:
  5813   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5814     now formalized using the Ring_and_Field theory mentioned above.
  5815   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5816     than before, because now they are set up once in a generic manner.
  5817   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5818     Look for the general versions in Ring_and_Field (and Power if they concern
  5819     exponentiation).
  5820 
  5821 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5822 
  5823 * Records:
  5824   - Record types are now by default printed with their type abbreviation
  5825     instead of the list of all field types. This can be configured via
  5826     the reference "print_record_type_abbr".
  5827   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5828     (not enabled by default).
  5829   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5830     EX x. x = sel r to True (not enabled by default).
  5831   - Tactic "record_split_simp_tac" to split and simplify records added.
  5832 
  5833 * 'specification' command added, allowing for definition by
  5834   specification.  There is also an 'ax_specification' command that
  5835   introduces the new constants axiomatically.
  5836 
  5837 * arith(_tac) is now able to generate counterexamples for reals as well.
  5838 
  5839 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5840 
  5841 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5842   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5843 
  5844 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5845   matrix theory to linear programming.
  5846 
  5847 * Unions and Intersections:
  5848   The latex output syntax of UN and INT has been changed
  5849   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5850   i.e. the index formulae has become a subscript.
  5851   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5852 
  5853 * Unions and Intersections over Intervals:
  5854   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5855   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5856   like in normal math, and corresponding versions for < and for intersection.
  5857 
  5858 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5859   lexicographic dictonary ordering has been added as "lexord".
  5860 
  5861 * ML: the legacy theory structures Int and List have been removed. They had
  5862   conflicted with ML Basis Library structures having the same names.
  5863 
  5864 * 'refute' command added to search for (finite) countermodels.  Only works
  5865   for a fragment of HOL.  The installation of an external SAT solver is
  5866   highly recommended.  See "HOL/Refute.thy" for details.
  5867 
  5868 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5869   formulae under an assignment of free variables to random values.
  5870   In contrast to 'refute', it can deal with inductive datatypes,
  5871   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5872   for examples.
  5873 
  5874 
  5875 *** HOLCF ***
  5876 
  5877 * Streams now come with concatenation and are part of the HOLCF image
  5878 
  5879 
  5880 
  5881 New in Isabelle2003 (May 2003)
  5882 ------------------------------
  5883 
  5884 *** General ***
  5885 
  5886 * Provers/simplifier:
  5887 
  5888   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5889     Assumptions are now subject to complete mutual simplification,
  5890     not just from left to right. The simplifier now preserves
  5891     the order of assumptions.
  5892 
  5893     Potential INCOMPATIBILITY:
  5894 
  5895     -- simp sometimes diverges where the old version did
  5896        not, e.g. invoking simp on the goal
  5897 
  5898         [| P (f x); y = x; f x = f y |] ==> Q
  5899 
  5900        now gives rise to the infinite reduction sequence
  5901 
  5902         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5903 
  5904        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5905        kind of problem.
  5906 
  5907     -- Tactics combining classical reasoner and simplification (such as auto)
  5908        are also affected by this change, because many of them rely on
  5909        simp. They may sometimes diverge as well or yield a different numbers
  5910        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5911        in case of problems. Sometimes subsequent calls to the classical
  5912        reasoner will fail because a preceeding call to the simplifier too
  5913        eagerly simplified the goal, e.g. deleted redundant premises.
  5914 
  5915   - The simplifier trace now shows the names of the applied rewrite rules
  5916 
  5917   - You can limit the number of recursive invocations of the simplifier
  5918     during conditional rewriting (where the simplifie tries to solve the
  5919     conditions before applying the rewrite rule):
  5920     ML "simp_depth_limit := n"
  5921     where n is an integer. Thus you can force termination where previously
  5922     the simplifier would diverge.
  5923 
  5924   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5925 
  5926   - No longer aborts on failed congruence proof.  Instead, the
  5927     congruence is ignored.
  5928 
  5929 * Pure: New generic framework for extracting programs from constructive
  5930   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5931   as HOL/Extraction for some case studies.
  5932 
  5933 * Pure: The main goal of the proof state is no longer shown by default, only
  5934 the subgoals. This behaviour is controlled by a new flag.
  5935    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5936 (ML: Proof.show_main_goal).
  5937 
  5938 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5939 rules whose conclusion matches subgoal 1:
  5940       PG menu: Isabelle/Isar -> Show me -> matching rules
  5941 The rules are ordered by how closely they match the subgoal.
  5942 In particular, rules that solve a subgoal outright are displayed first
  5943 (or rather last, the way they are printed).
  5944 (ML: ProofGeneral.print_intros())
  5945 
  5946 * Pure: New flag trace_unify_fail causes unification to print
  5947 diagnostic information (PG: in trace buffer) when it fails. This is
  5948 useful for figuring out why single step proofs like rule, erule or
  5949 assumption failed.
  5950 
  5951 * Pure: Locale specifications now produce predicate definitions
  5952 according to the body of text (covering assumptions modulo local
  5953 definitions); predicate "loc_axioms" covers newly introduced text,
  5954 while "loc" is cumulative wrt. all included locale expressions; the
  5955 latter view is presented only on export into the global theory
  5956 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5957 on the old view without predicates;
  5958 
  5959 * Pure: predefined locales "var" and "struct" are useful for sharing
  5960 parameters (as in CASL, for example); just specify something like
  5961 ``var x + var y + struct M'' as import;
  5962 
  5963 * Pure: improved thms_containing: proper indexing of facts instead of
  5964 raw theorems; check validity of results wrt. current name space;
  5965 include local facts of proof configuration (also covers active
  5966 locales), cover fixed variables in index; may use "_" in term
  5967 specification; an optional limit for the number of printed facts may
  5968 be given (the default is 40);
  5969 
  5970 * Pure: disallow duplicate fact bindings within new-style theory files
  5971 (batch-mode only);
  5972 
  5973 * Provers: improved induct method: assumptions introduced by case
  5974 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5975 the goal statement); "foo" still refers to all facts collectively;
  5976 
  5977 * Provers: the function blast.overloaded has been removed: all constants
  5978 are regarded as potentially overloaded, which improves robustness in exchange
  5979 for slight decrease in efficiency;
  5980 
  5981 * Provers/linorder: New generic prover for transitivity reasoning over
  5982 linear orders.  Note: this prover is not efficient!
  5983 
  5984 * Isar: preview of problems to finish 'show' now produce an error
  5985 rather than just a warning (in interactive mode);
  5986 
  5987 
  5988 *** HOL ***
  5989 
  5990 * arith(_tac)
  5991 
  5992  - Produces a counter example if it cannot prove a goal.
  5993    Note that the counter example may be spurious if the goal is not a formula
  5994    of quantifier-free linear arithmetic.
  5995    In ProofGeneral the counter example appears in the trace buffer.
  5996 
  5997  - Knows about div k and mod k where k is a numeral of type nat or int.
  5998 
  5999  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  6000    linear arithmetic fails. This takes account of quantifiers and divisibility.
  6001    Presburger arithmetic can also be called explicitly via presburger(_tac).
  6002 
  6003 * simp's arithmetic capabilities have been enhanced a bit: it now
  6004 takes ~= in premises into account (by performing a case split);
  6005 
  6006 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  6007 are distributed over a sum of terms;
  6008 
  6009 * New tactic "trans_tac" and method "trans" instantiate
  6010 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  6011 "<=", "<" and "=").
  6012 
  6013 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  6014 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  6015 
  6016 * 'typedef' command has new option "open" to suppress the set
  6017 definition;
  6018 
  6019 * functions Min and Max on finite sets have been introduced (theory
  6020 Finite_Set);
  6021 
  6022 * attribute [symmetric] now works for relations as well; it turns
  6023 (x,y) : R^-1 into (y,x) : R, and vice versa;
  6024 
  6025 * induct over a !!-quantified statement (say !!x1..xn):
  6026   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  6027 
  6028 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  6029 %x. None. Warning: empty_def now refers to the previously hidden definition
  6030 of the empty set.
  6031 
  6032 * Algebra: formalization of classical algebra.  Intended as base for
  6033 any algebraic development in Isabelle.  Currently covers group theory
  6034 (up to Sylow's theorem) and ring theory (Universal Property of
  6035 Univariate Polynomials).  Contributions welcome;
  6036 
  6037 * GroupTheory: deleted, since its material has been moved to Algebra;
  6038 
  6039 * Complex: new directory of the complex numbers with numeric constants,
  6040 nonstandard complex numbers, and some complex analysis, standard and
  6041 nonstandard (Jacques Fleuriot);
  6042 
  6043 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  6044 
  6045 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  6046 Fleuriot);
  6047 
  6048 * Real/HahnBanach: updated and adapted to locales;
  6049 
  6050 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  6051 Gray and Kramer);
  6052 
  6053 * UNITY: added the Meier-Sanders theory of progress sets;
  6054 
  6055 * MicroJava: bytecode verifier and lightweight bytecode verifier
  6056 as abstract algorithms, instantiated to the JVM;
  6057 
  6058 * Bali: Java source language formalization. Type system, operational
  6059 semantics, axiomatic semantics. Supported language features:
  6060 classes, interfaces, objects,virtual methods, static methods,
  6061 static/instance fields, arrays, access modifiers, definite
  6062 assignment, exceptions.
  6063 
  6064 
  6065 *** ZF ***
  6066 
  6067 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  6068 universe, etc.);
  6069 
  6070 * Main ZF: virtually all theories converted to new-style format;
  6071 
  6072 
  6073 *** ML ***
  6074 
  6075 * Pure: Tactic.prove provides sane interface for internal proofs;
  6076 omits the infamous "standard" operation, so this is more appropriate
  6077 than prove_goalw_cterm in many situations (e.g. in simprocs);
  6078 
  6079 * Pure: improved error reporting of simprocs;
  6080 
  6081 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  6082 up simprocs;
  6083 
  6084 
  6085 *** Document preparation ***
  6086 
  6087 * uses \par instead of \\ for line breaks in theory text. This may
  6088 shift some page breaks in large documents. To get the old behaviour
  6089 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  6090 
  6091 * minimized dependencies of isabelle.sty and isabellesym.sty on
  6092 other packages
  6093 
  6094 * \<euro> now needs package babel/greek instead of marvosym (which
  6095 broke \Rightarrow)
  6096 
  6097 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  6098 textcomp package)
  6099 
  6100 
  6101 
  6102 New in Isabelle2002 (March 2002)
  6103 --------------------------------
  6104 
  6105 *** Document preparation ***
  6106 
  6107 * greatly simplified document preparation setup, including more
  6108 graceful interpretation of isatool usedir -i/-d/-D options, and more
  6109 instructive isatool mkdir; users should basically be able to get
  6110 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  6111 users may run a separate document processing stage manually like this:
  6112 "isatool usedir -D output HOL Test && isatool document Test/output";
  6113 
  6114 * theory dependency graph may now be incorporated into documents;
  6115 isatool usedir -g true will produce session_graph.eps/.pdf for use
  6116 with \includegraphics of LaTeX;
  6117 
  6118 * proper spacing of consecutive markup elements, especially text
  6119 blocks after section headings;
  6120 
  6121 * support bold style (for single symbols only), input syntax is like
  6122 this: "\<^bold>\<alpha>" or "\<^bold>A";
  6123 
  6124 * \<bullet> is now output as bold \cdot by default, which looks much
  6125 better in printed text;
  6126 
  6127 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  6128 note that these symbols are currently unavailable in Proof General /
  6129 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  6130 
  6131 * isatool latex no longer depends on changed TEXINPUTS, instead
  6132 isatool document copies the Isabelle style files to the target
  6133 location;
  6134 
  6135 
  6136 *** Isar ***
  6137 
  6138 * Pure/Provers: improved proof by cases and induction;
  6139   - 'case' command admits impromptu naming of parameters (such as
  6140     "case (Suc n)");
  6141   - 'induct' method divinates rule instantiation from the inductive
  6142     claim; no longer requires excessive ?P bindings for proper
  6143     instantiation of cases;
  6144   - 'induct' method properly enumerates all possibilities of set/type
  6145     rules; as a consequence facts may be also passed through *type*
  6146     rules without further ado;
  6147   - 'induct' method now derives symbolic cases from the *rulified*
  6148     rule (before it used to rulify cases stemming from the internal
  6149     atomized version); this means that the context of a non-atomic
  6150     statement becomes is included in the hypothesis, avoiding the
  6151     slightly cumbersome show "PROP ?case" form;
  6152   - 'induct' may now use elim-style induction rules without chaining
  6153     facts, using ``missing'' premises from the goal state; this allows
  6154     rules stemming from inductive sets to be applied in unstructured
  6155     scripts, while still benefitting from proper handling of non-atomic
  6156     statements; NB: major inductive premises need to be put first, all
  6157     the rest of the goal is passed through the induction;
  6158   - 'induct' proper support for mutual induction involving non-atomic
  6159     rule statements (uses the new concept of simultaneous goals, see
  6160     below);
  6161   - append all possible rule selections, but only use the first
  6162     success (no backtracking);
  6163   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  6164   - undeclared rule case names default to numbers 1, 2, 3, ...;
  6165   - added 'print_induct_rules' (covered by help item in recent Proof
  6166     General versions);
  6167   - moved induct/cases attributes to Pure, methods to Provers;
  6168   - generic method setup instantiated for FOL and HOL;
  6169 
  6170 * Pure: support multiple simultaneous goal statements, for example
  6171 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  6172 meta-level mechanism, this acts as if several individual goals had
  6173 been stated separately; in particular common proof methods need to be
  6174 repeated in order to cover all claims; note that a single elimination
  6175 step is *not* sufficient to establish the two conjunctions, so this
  6176 fails:
  6177 
  6178   assume "A & B" then have A and B ..   (*".." fails*)
  6179 
  6180 better use "obtain" in situations as above; alternative refer to
  6181 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  6182 
  6183 * Pure: proper integration with ``locales''; unlike the original
  6184 version by Florian Kammller, Isar locales package high-level proof
  6185 contexts rather than raw logical ones (e.g. we admit to include
  6186 attributes everywhere); operations on locales include merge and
  6187 rename; support for implicit arguments (``structures''); simultaneous
  6188 type-inference over imports and text; see also HOL/ex/Locales.thy for
  6189 some examples;
  6190 
  6191 * Pure: the following commands have been ``localized'', supporting a
  6192 target locale specification "(in name)": 'lemma', 'theorem',
  6193 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  6194 stored both within the locale and at the theory level (exported and
  6195 qualified by the locale name);
  6196 
  6197 * Pure: theory goals may now be specified in ``long'' form, with
  6198 ad-hoc contexts consisting of arbitrary locale elements. for example
  6199 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  6200 definitions may be given, too); the result is a meta-level rule with
  6201 the context elements being discharged in the obvious way;
  6202 
  6203 * Pure: new proof command 'using' allows to augment currently used
  6204 facts after a goal statement ('using' is syntactically analogous to
  6205 'apply', but acts on the goal's facts only); this allows chained facts
  6206 to be separated into parts given before and after a claim, as in
  6207 ``from a and b have C using d and e <proof>'';
  6208 
  6209 * Pure: renamed "antecedent" case to "rule_context";
  6210 
  6211 * Pure: new 'judgment' command records explicit information about the
  6212 object-logic embedding (used by several tools internally); no longer
  6213 use hard-wired "Trueprop";
  6214 
  6215 * Pure: added 'corollary' command;
  6216 
  6217 * Pure: fixed 'token_translation' command;
  6218 
  6219 * Pure: removed obsolete 'exported' attribute;
  6220 
  6221 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  6222 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  6223 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  6224 
  6225 * Pure: method 'atomize' presents local goal premises as object-level
  6226 statements (atomic meta-level propositions); setup controlled via
  6227 rewrite rules declarations of 'atomize' attribute; example
  6228 application: 'induct' method with proper rule statements in improper
  6229 proof *scripts*;
  6230