NEWS
author blanchet
Mon Jun 27 14:56:10 2011 +0200 (2011-06-27)
changeset 43570 ccfb3623a68a
parent 43527 1aacef7471c2
child 43573 81f7dca3e542
permissions -rw-r--r--
document changes to Sledgehammer and "try"
     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 * Finite_Set.thy: more coherent development of fold_set locales:
    64 
    65     locale fun_left_comm ~> locale comp_fun_commute
    66     locale fun_left_comm_idem ~> locale comp_fun_idem
    67     
    68 Both use point-free characterisation; interpretation proofs may need adjustment.
    69 INCOMPATIBILITY.
    70 
    71 * Code generation:
    72   - theory Library/Code_Char_ord provides native ordering of characters
    73     in the target language.
    74     
    75 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
    76 
    77 * Nitpick:
    78   - Added "need" and "total_consts" options.
    79   - Reintroduced "show_skolems" option by popular demand.
    80   - Renamed attribute: nitpick_def ~> nitpick_unfold.
    81     INCOMPATIBILITY.
    82 
    83 * Sledgehammer:
    84   - sledgehammer available_provers ~> sledgehammer supported_provers
    85     INCOMPATIBILITY.
    86   - Added support for SNARK and ToFoF-E on SystemOnTPTP and for simply typed
    87     TPTP problems (TFF).
    88   - Added "type_sys", "max_mono_iters", and "max_new_mono_instances" options.
    89   - Removed "full_types" option and corresponding Proof General menu item.
    90 
    91 * Metis:
    92   - Removed "metisF" -- use "metis" instead.
    93   - Obsoleted "metisFT" -- use "metis (full_types)" instead.
    94 
    95 * "try":
    96   - Renamed "try_methods" and added "simp:", "intro:", "dest:", and "elim:"
    97     options. INCOMPATIBILITY.
    98   - Introduced "try" that not only runs "try_methods" but also "solve_direct",
    99     "sledgehammer", "quickcheck", and "nitpick".
   100 
   101 * Quickcheck:
   102   - Added "eval" option to evaluate terms for the found counterexample
   103     (currently only supported by the default (exhaustive) tester)
   104   - Added post-processing of terms to obtain readable counterexamples
   105     (currently only supported by the default (exhaustive) tester)
   106   - New counterexample generator quickcheck[narrowing] enables
   107     narrowing-based testing.
   108     It requires that the Glasgow Haskell compiler is installed and
   109     its location is known to Isabelle with the environment variable
   110     ISABELLE_GHC.
   111 
   112 * Function package: discontinued option "tailrec".
   113 INCOMPATIBILITY. Use partial_function instead.
   114 
   115 * HOL-Probability:
   116   - Caratheodory's extension lemma is now proved for ring_of_sets.
   117   - Infinite products of probability measures are now available.
   118   - Use extended reals instead of positive extended reals.
   119     INCOMPATIBILITY.
   120 
   121 
   122 *** Document preparation ***
   123 
   124 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
   125 isar-ref manual.
   126 
   127 * Localized \isabellestyle switch can be used within blocks or groups
   128 like this:
   129 
   130   \isabellestyle{it}  %preferred default
   131   {\isabellestylett @{text "typewriter stuff"}}
   132 
   133 * New term style "isub" as ad-hoc conversion of variables x1, y23 into
   134 subscripted form x\<^isub>1, y\<^isub>2\<^isub>3.
   135 
   136 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
   137 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
   138 
   139 
   140 *** ML ***
   141 
   142 * Isabelle_Process.is_active allows tools to check if the official
   143 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
   144 (better known as Proof General).
   145 
   146 * Structure Proof_Context follows standard naming scheme.  Old
   147 ProofContext is still available for some time as legacy alias.
   148 
   149 * Structure Timing provides various operations for timing; supersedes
   150 former start_timing/end_timing etc.
   151 
   152 * Path.print is the official way to show file-system paths to users
   153 (including quotes etc.).
   154 
   155 * Inner syntax: identifiers in parse trees of generic categories
   156 "logic", "aprop", "idt" etc. carry position information (disguised as
   157 type constraints).  Occasional INCOMPATIBILITY with non-compliant
   158 translations that choke on unexpected type constraints.  Positions can
   159 be stripped in ML translations via Syntax.strip_positions /
   160 Syntax.strip_positions_ast, or via the syntax constant
   161 "_strip_positions" within parse trees.  As last resort, positions can
   162 be disabled via the configuration option Syntax.positions, which is
   163 called "syntax_positions" in Isar attribute syntax.
   164 
   165 * Discontinued special status of various ML structures that contribute
   166 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
   167 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
   168 refer directly to Ast.Constant, Lexicon.is_identifier,
   169 Syntax_Trans.mk_binder_tr etc.
   170 
   171 * Typed print translation: discontinued show_sorts argument, which is
   172 already available via context of "advanced" translation.
   173 
   174 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
   175 goal states; body tactic needs to address all subgoals uniformly.
   176 
   177 * Slightly more special eq_list/eq_set, with shortcut involving
   178 pointer equality (assumes that eq relation is reflexive).
   179 
   180 * Classical tactics use proper Proof.context instead of historic types
   181 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
   182 operate directly on Proof.context.  Raw type claset retains its use as
   183 snapshot of the classical context, which can be recovered via
   184 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
   185 INCOMPATIBILITY, classical tactics and derived proof methods require
   186 proper Proof.context.
   187 
   188 
   189 
   190 New in Isabelle2011 (January 2011)
   191 ----------------------------------
   192 
   193 *** General ***
   194 
   195 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
   196 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
   197 useful tooltips and hyperlinks produced from its static analysis.  The
   198 bundled component provides an executable Isabelle tool that can be run
   199 like this:
   200 
   201   Isabelle2011/bin/isabelle jedit
   202 
   203 * Significantly improved Isabelle/Isar implementation manual.
   204 
   205 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
   206 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
   207 while the default heap location within that directory lacks that extra
   208 suffix.  This isolates multiple Isabelle installations from each
   209 other, avoiding problems with old settings in new versions.
   210 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
   211 
   212 * Source files are always encoded as UTF-8, instead of old-fashioned
   213 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   214 the following package declarations:
   215 
   216   \usepackage[utf8]{inputenc}
   217   \usepackage{textcomp}
   218 
   219 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   220 a Unicode character is treated as a single symbol, not a sequence of
   221 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   222 contain symbols without further backslash escapes, Unicode can now be
   223 used here as well.  Recall that Symbol.explode in ML provides a
   224 consistent view on symbols, while raw explode (or String.explode)
   225 merely give a byte-oriented representation.
   226 
   227 * Theory loader: source files are primarily located via the master
   228 directory of each theory node (where the .thy file itself resides).
   229 The global load path is still partially available as legacy feature.
   230 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   231 explicit paths, relatively to the theory.
   232 
   233 * Special treatment of ML file names has been discontinued.
   234 Historically, optional extensions .ML or .sml were added on demand --
   235 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   236 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   237 
   238 * Various options that affect pretty printing etc. are now properly
   239 handled within the context via configuration options, instead of
   240 unsynchronized references or print modes.  There are both ML Config.T
   241 entities and Isar declaration attributes to access these.
   242 
   243   ML (Config.T)                 Isar (attribute)
   244 
   245   eta_contract                  eta_contract
   246   show_brackets                 show_brackets
   247   show_sorts                    show_sorts
   248   show_types                    show_types
   249   show_question_marks           show_question_marks
   250   show_consts                   show_consts
   251   show_abbrevs                  show_abbrevs
   252 
   253   Syntax.ast_trace              syntax_ast_trace
   254   Syntax.ast_stat               syntax_ast_stat
   255   Syntax.ambiguity_level        syntax_ambiguity_level
   256 
   257   Goal_Display.goals_limit      goals_limit
   258   Goal_Display.show_main_goal   show_main_goal
   259 
   260   Method.rule_trace             rule_trace
   261 
   262   Thy_Output.display            thy_output_display
   263   Thy_Output.quotes             thy_output_quotes
   264   Thy_Output.indent             thy_output_indent
   265   Thy_Output.source             thy_output_source
   266   Thy_Output.break              thy_output_break
   267 
   268 Note that corresponding "..._default" references in ML may only be
   269 changed globally at the ROOT session setup, but *not* within a theory.
   270 The option "show_abbrevs" supersedes the former print mode
   271 "no_abbrevs" with inverted meaning.
   272 
   273 * More systematic naming of some configuration options.
   274 INCOMPATIBILITY.
   275 
   276   trace_simp  ~>  simp_trace
   277   debug_simp  ~>  simp_debug
   278 
   279 * Support for real valued configuration options, using simplistic
   280 floating-point notation that coincides with the inner syntax for
   281 float_token.
   282 
   283 * Support for real valued preferences (with approximative PGIP type):
   284 front-ends need to accept "pgint" values in float notation.
   285 INCOMPATIBILITY.
   286 
   287 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   288 DejaVu Sans.
   289 
   290 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   291 
   292 
   293 *** Pure ***
   294 
   295 * Command 'type_synonym' (with single argument) replaces somewhat
   296 outdated 'types', which is still available as legacy feature for some
   297 time.
   298 
   299 * Command 'nonterminal' (with 'and' separated list of arguments)
   300 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   301 
   302 * Command 'notepad' replaces former 'example_proof' for
   303 experimentation in Isar without any result.  INCOMPATIBILITY.
   304 
   305 * Locale interpretation commands 'interpret' and 'sublocale' accept
   306 lists of equations to map definitions in a locale to appropriate
   307 entities in the context of the interpretation.  The 'interpretation'
   308 command already provided this functionality.
   309 
   310 * Diagnostic command 'print_dependencies' prints the locale instances
   311 that would be activated if the specified expression was interpreted in
   312 the current context.  Variant "print_dependencies!" assumes a context
   313 without interpretations.
   314 
   315 * Diagnostic command 'print_interps' prints interpretations in proofs
   316 in addition to interpretations in theories.
   317 
   318 * Discontinued obsolete 'global' and 'local' commands to manipulate
   319 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   320 Sign.root_path and Sign.local_path may be applied directly where this
   321 feature is still required for historical reasons.
   322 
   323 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   324 'definition' instead.
   325 
   326 * The "prems" fact, which refers to the accidental collection of
   327 foundational premises in the context, is now explicitly marked as
   328 legacy feature and will be discontinued soon.  Consider using "assms"
   329 of the head statement or reference facts by explicit names.
   330 
   331 * Document antiquotations @{class} and @{type} print classes and type
   332 constructors.
   333 
   334 * Document antiquotation @{file} checks file/directory entries within
   335 the local file system.
   336 
   337 
   338 *** HOL ***
   339 
   340 * Coercive subtyping: functions can be declared as coercions and type
   341 inference will add them as necessary upon input of a term.  Theory
   342 Complex_Main declares real :: nat => real and real :: int => real as
   343 coercions. A coercion function f is declared like this:
   344 
   345   declare [[coercion f]]
   346 
   347 To lift coercions through type constructors (e.g. from nat => real to
   348 nat list => real list), map functions can be declared, e.g.
   349 
   350   declare [[coercion_map map]]
   351 
   352 Currently coercion inference is activated only in theories including
   353 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   354 the configuration option "coercion_enabled", e.g. it can be enabled in
   355 other theories like this:
   356 
   357   declare [[coercion_enabled]]
   358 
   359 * Command 'partial_function' provides basic support for recursive
   360 function definitions over complete partial orders.  Concrete instances
   361 are provided for i) the option type, ii) tail recursion on arbitrary
   362 types, and iii) the heap monad of Imperative_HOL.  See
   363 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   364 for examples.
   365 
   366 * Function package: f.psimps rules are no longer implicitly declared
   367 as [simp].  INCOMPATIBILITY.
   368 
   369 * Datatype package: theorems generated for executable equality (class
   370 "eq") carry proper names and are treated as default code equations.
   371 
   372 * Inductive package: now offers command 'inductive_simps' to
   373 automatically derive instantiated and simplified equations for
   374 inductive predicates, similar to 'inductive_cases'.
   375 
   376 * Command 'enriched_type' allows to register properties of the
   377 functorial structure of types.
   378 
   379 * Improved infrastructure for term evaluation using code generator
   380 techniques, in particular static evaluation conversions.
   381 
   382 * Code generator: Scala (2.8 or higher) has been added to the target
   383 languages.
   384 
   385 * Code generator: globbing constant expressions "*" and "Theory.*"
   386 have been replaced by the more idiomatic "_" and "Theory._".
   387 INCOMPATIBILITY.
   388 
   389 * Code generator: export_code without explicit file declaration prints
   390 to standard output.  INCOMPATIBILITY.
   391 
   392 * Code generator: do not print function definitions for case
   393 combinators any longer.
   394 
   395 * Code generator: simplification with rules determined with
   396 src/Tools/Code/code_simp.ML and method "code_simp".
   397 
   398 * Code generator for records: more idiomatic representation of record
   399 types.  Warning: records are not covered by ancient SML code
   400 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   401 rep_datatype declaration helps to succeed then:
   402 
   403   record 'a foo = ...
   404   ...
   405   rep_datatype foo_ext ...
   406 
   407 * Records: logical foundation type for records does not carry a
   408 '_type' suffix any longer (obsolete due to authentic syntax).
   409 INCOMPATIBILITY.
   410 
   411 * Quickcheck now by default uses exhaustive testing instead of random
   412 testing.  Random testing can be invoked by "quickcheck [random]",
   413 exhaustive testing by "quickcheck [exhaustive]".
   414 
   415 * Quickcheck instantiates polymorphic types with small finite
   416 datatypes by default. This enables a simple execution mechanism to
   417 handle quantifiers and function equality over the finite datatypes.
   418 
   419 * Quickcheck random generator has been renamed from "code" to
   420 "random".  INCOMPATIBILITY.
   421 
   422 * Quickcheck now has a configurable time limit which is set to 30
   423 seconds by default. This can be changed by adding [timeout = n] to the
   424 quickcheck command. The time limit for Auto Quickcheck is still set
   425 independently.
   426 
   427 * Quickcheck in locales considers interpretations of that locale for
   428 counter example search.
   429 
   430 * Sledgehammer:
   431   - Added "smt" and "remote_smt" provers based on the "smt" proof
   432     method. See the Sledgehammer manual for details ("isabelle doc
   433     sledgehammer").
   434   - Renamed commands:
   435     sledgehammer atp_info ~> sledgehammer running_provers
   436     sledgehammer atp_kill ~> sledgehammer kill_provers
   437     sledgehammer available_atps ~> sledgehammer available_provers
   438     INCOMPATIBILITY.
   439   - Renamed options:
   440     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   441     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   442     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   443     (and "ms" and "min" are no longer supported)
   444     INCOMPATIBILITY.
   445 
   446 * Nitpick:
   447   - Renamed options:
   448     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   449     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   450     INCOMPATIBILITY.
   451   - Added support for partial quotient types.
   452   - Added local versions of the "Nitpick.register_xxx" functions.
   453   - Added "whack" option.
   454   - Allow registration of quotient types as codatatypes.
   455   - Improved "merge_type_vars" option to merge more types.
   456   - Removed unsound "fast_descrs" option.
   457   - Added custom symmetry breaking for datatypes, making it possible to reach
   458     higher cardinalities.
   459   - Prevent the expansion of too large definitions.
   460 
   461 * Proof methods "metis" and "meson" now have configuration options
   462 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   463 to diagnose these tools. E.g.
   464 
   465     using [[metis_trace = true]]
   466 
   467 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   468 manually as command 'solve_direct'.
   469 
   470 * The default SMT solver Z3 must be enabled explicitly (due to
   471 licensing issues) by setting the environment variable
   472 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   473 commercial applications, the SMT solver CVC3 is provided as fall-back;
   474 changing the SMT solver is done via the configuration option
   475 "smt_solver".
   476 
   477 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   478 i.e. "remote_cvc3" and "remote_z3".
   479 
   480 * Added basic SMT support for datatypes, records, and typedefs using
   481 the oracle mode (no proofs).  Direct support of pairs has been dropped
   482 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   483 support for a similar behavior).  Minor INCOMPATIBILITY.
   484 
   485 * Changed SMT configuration options:
   486   - Renamed:
   487     z3_proofs ~> smt_oracle (with inverted meaning)
   488     z3_trace_assms ~> smt_trace_used_facts
   489     INCOMPATIBILITY.
   490   - Added:
   491     smt_verbose
   492     smt_random_seed
   493     smt_datatypes
   494     smt_infer_triggers
   495     smt_monomorph_limit
   496     cvc3_options
   497     remote_cvc3_options
   498     remote_z3_options
   499     yices_options
   500 
   501 * Boogie output files (.b2i files) need to be declared in the theory
   502 header.
   503 
   504 * Simplification procedure "list_to_set_comprehension" rewrites list
   505 comprehensions applied to List.set to set comprehensions.  Occasional
   506 INCOMPATIBILITY, may be deactivated like this:
   507 
   508   declare [[simproc del: list_to_set_comprehension]]
   509 
   510 * Removed old version of primrec package.  INCOMPATIBILITY.
   511 
   512 * Removed simplifier congruence rule of "prod_case", as has for long
   513 been the case with "split".  INCOMPATIBILITY.
   514 
   515 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   516 
   517 * Removed [split_format ... and ... and ...] version of
   518 [split_format].  Potential INCOMPATIBILITY.
   519 
   520 * Predicate "sorted" now defined inductively, with nice induction
   521 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   522 
   523 * Constant "contents" renamed to "the_elem", to free the generic name
   524 contents for other uses.  INCOMPATIBILITY.
   525 
   526 * Renamed class eq and constant eq (for code generation) to class
   527 equal and constant equal, plus renaming of related facts and various
   528 tuning.  INCOMPATIBILITY.
   529 
   530 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   531 
   532 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   533 INCOMPATIBILITY.
   534 
   535 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   536 avoid confusion with finite sets.  INCOMPATIBILITY.
   537 
   538 * Abandoned locales equiv, congruent and congruent2 for equivalence
   539 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   540 for congruent(2)).
   541 
   542 * Some previously unqualified names have been qualified:
   543 
   544   types
   545     bool ~> HOL.bool
   546     nat ~> Nat.nat
   547 
   548   constants
   549     Trueprop ~> HOL.Trueprop
   550     True ~> HOL.True
   551     False ~> HOL.False
   552     op & ~> HOL.conj
   553     op | ~> HOL.disj
   554     op --> ~> HOL.implies
   555     op = ~> HOL.eq
   556     Not ~> HOL.Not
   557     The ~> HOL.The
   558     All ~> HOL.All
   559     Ex ~> HOL.Ex
   560     Ex1 ~> HOL.Ex1
   561     Let ~> HOL.Let
   562     If ~> HOL.If
   563     Ball ~> Set.Ball
   564     Bex ~> Set.Bex
   565     Suc ~> Nat.Suc
   566     Pair ~> Product_Type.Pair
   567     fst ~> Product_Type.fst
   568     snd ~> Product_Type.snd
   569     curry ~> Product_Type.curry
   570     op : ~> Set.member
   571     Collect ~> Set.Collect
   572 
   573 INCOMPATIBILITY.
   574 
   575 * More canonical naming convention for some fundamental definitions:
   576 
   577     bot_bool_eq ~> bot_bool_def
   578     top_bool_eq ~> top_bool_def
   579     inf_bool_eq ~> inf_bool_def
   580     sup_bool_eq ~> sup_bool_def
   581     bot_fun_eq  ~> bot_fun_def
   582     top_fun_eq  ~> top_fun_def
   583     inf_fun_eq  ~> inf_fun_def
   584     sup_fun_eq  ~> sup_fun_def
   585 
   586 INCOMPATIBILITY.
   587 
   588 * More stylized fact names:
   589 
   590   expand_fun_eq ~> fun_eq_iff
   591   expand_set_eq ~> set_eq_iff
   592   set_ext       ~> set_eqI
   593   nat_number    ~> eval_nat_numeral
   594 
   595 INCOMPATIBILITY.
   596 
   597 * Refactoring of code-generation specific operations in theory List:
   598 
   599   constants
   600     null ~> List.null
   601 
   602   facts
   603     mem_iff ~> member_def
   604     null_empty ~> null_def
   605 
   606 INCOMPATIBILITY.  Note that these were not supposed to be used
   607 regularly unless for striking reasons; their main purpose was code
   608 generation.
   609 
   610 Various operations from the Haskell prelude are used for generating
   611 Haskell code.
   612 
   613 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   614 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   615 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   616 
   617 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   618 "*" and "+" respectively.  INCOMPATIBILITY.
   619 
   620 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   621 "Sum_Type.Plus" instead.
   622 
   623 * Constant "split" has been merged with constant "prod_case"; names of
   624 ML functions, facts etc. involving split have been retained so far,
   625 though.  INCOMPATIBILITY.
   626 
   627 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   628 instead.  INCOMPATIBILITY.
   629 
   630 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   631 INCOMPATIBILITY.
   632 
   633 * Former theory Library/Enum is now part of the HOL-Main image.
   634 INCOMPATIBILITY: all constants of the Enum theory now have to be
   635 referred to by its qualified name.
   636 
   637   enum    ~>  Enum.enum
   638   nlists  ~>  Enum.nlists
   639   product ~>  Enum.product
   640 
   641 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   642 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   643 INCOMPATIBILITY.
   644 
   645 * Theory Library/SetsAndFunctions has been split into
   646 Library/Function_Algebras and Library/Set_Algebras; canonical names
   647 for instance definitions for functions; various improvements.
   648 INCOMPATIBILITY.
   649 
   650 * Theory Library/Multiset provides stable quicksort implementation of
   651 sort_key.
   652 
   653 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   654 INCOMPATIBILITY.
   655 
   656 * Session Multivariate_Analysis: introduced a type class for euclidean
   657 space.  Most theorems are now stated in terms of euclidean spaces
   658 instead of finite cartesian products.
   659 
   660   types
   661     real ^ 'n ~>  'a::real_vector
   662               ~>  'a::euclidean_space
   663               ~>  'a::ordered_euclidean_space
   664         (depends on your needs)
   665 
   666   constants
   667      _ $ _        ~> _ $$ _
   668      \<chi> x. _  ~> \<chi>\<chi> x. _
   669      CARD('n)     ~> DIM('a)
   670 
   671 Also note that the indices are now natural numbers and not from some
   672 finite type. Finite cartesian products of euclidean spaces, products
   673 of euclidean spaces the real and complex numbers are instantiated to
   674 be euclidean_spaces.  INCOMPATIBILITY.
   675 
   676 * Session Probability: introduced pextreal as positive extended real
   677 numbers.  Use pextreal as value for measures.  Introduce the
   678 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   679 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   680 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   681 
   682 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   683 INCOMPATIBILITY.
   684 
   685 * Session SPARK (with image HOL-SPARK) provides commands to load and
   686 prove verification conditions generated by the SPARK Ada program
   687 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   688 
   689 
   690 *** HOL-Algebra ***
   691 
   692 * Theorems for additive ring operations (locale abelian_monoid and
   693 descendants) are generated by interpretation from their multiplicative
   694 counterparts.  Names (in particular theorem names) have the mandatory
   695 qualifier 'add'.  Previous theorem names are redeclared for
   696 compatibility.
   697 
   698 * Structure "int_ring" is now an abbreviation (previously a
   699 definition).  This fits more natural with advanced interpretations.
   700 
   701 
   702 *** HOLCF ***
   703 
   704 * The domain package now runs in definitional mode by default: The
   705 former command 'new_domain' is now called 'domain'.  To use the domain
   706 package in its original axiomatic mode, use 'domain (unsafe)'.
   707 INCOMPATIBILITY.
   708 
   709 * The new class "domain" is now the default sort.  Class "predomain"
   710 is an unpointed version of "domain". Theories can be updated by
   711 replacing sort annotations as shown below.  INCOMPATIBILITY.
   712 
   713   'a::type ~> 'a::countable
   714   'a::cpo  ~> 'a::predomain
   715   'a::pcpo ~> 'a::domain
   716 
   717 * The old type class "rep" has been superseded by class "domain".
   718 Accordingly, users of the definitional package must remove any
   719 "default_sort rep" declarations.  INCOMPATIBILITY.
   720 
   721 * The domain package (definitional mode) now supports unpointed
   722 predomain argument types, as long as they are marked 'lazy'. (Strict
   723 arguments must be in class "domain".) For example, the following
   724 domain definition now works:
   725 
   726   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   727 
   728 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   729 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   730 'a option, and 'a list.  Additionally, it configures fixrec and the
   731 domain package to work with these types.  For example:
   732 
   733   fixrec isInl :: "('a + 'b) u -> tr"
   734     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   735 
   736   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   737 
   738 * The "(permissive)" option of fixrec has been replaced with a
   739 per-equation "(unchecked)" option. See
   740 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
   741 
   742 * The "bifinite" class no longer fixes a constant "approx"; the class
   743 now just asserts that such a function exists.  INCOMPATIBILITY.
   744 
   745 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
   746 defines an embedding of type 'a defl into udom by default; instances
   747 of "bifinite" and "domain" classes are available in
   748 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
   749 
   750 * The syntax "REP('a)" has been replaced with "DEFL('a)".
   751 
   752 * The predicate "directed" has been removed.  INCOMPATIBILITY.
   753 
   754 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
   755 
   756 * The function "cprod_map" has been renamed to "prod_map".
   757 INCOMPATIBILITY.
   758 
   759 * The monadic bind operator on each powerdomain has new binder syntax
   760 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
   761 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
   762 
   763 * The infix syntax for binary union on each powerdomain has changed
   764 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
   765 syntax.  INCOMPATIBILITY.
   766 
   767 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
   768 still supported as an input translation.
   769 
   770 * Renamed some theorems (the original names are also still available).
   771 
   772   expand_fun_below   ~> fun_below_iff
   773   below_fun_ext      ~> fun_belowI
   774   expand_cfun_eq     ~> cfun_eq_iff
   775   ext_cfun           ~> cfun_eqI
   776   expand_cfun_below  ~> cfun_below_iff
   777   below_cfun_ext     ~> cfun_belowI
   778   cont2cont_Rep_CFun ~> cont2cont_APP
   779 
   780 * The Abs and Rep functions for various types have changed names.
   781 Related theorem names have also changed to match. INCOMPATIBILITY.
   782 
   783   Rep_CFun  ~> Rep_cfun
   784   Abs_CFun  ~> Abs_cfun
   785   Rep_Sprod ~> Rep_sprod
   786   Abs_Sprod ~> Abs_sprod
   787   Rep_Ssum  ~> Rep_ssum
   788   Abs_Ssum  ~> Abs_ssum
   789 
   790 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   791 been renamed to *_bottom_iff.  INCOMPATIBILITY.
   792 
   793 * Various changes to bisimulation/coinduction with domain package:
   794 
   795   - Definitions of "bisim" constants no longer mention definedness.
   796   - With mutual recursion, "bisim" predicate is now curried.
   797   - With mutual recursion, each type gets a separate coind theorem.
   798   - Variable names in bisim_def and coinduct rules have changed.
   799 
   800 INCOMPATIBILITY.
   801 
   802 * Case combinators generated by the domain package for type "foo" are
   803 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
   804 
   805 * Several theorems have been renamed to more accurately reflect the
   806 names of constants and types involved.  INCOMPATIBILITY.
   807 
   808   thelub_const    ~> lub_const
   809   lub_const       ~> is_lub_const
   810   thelubI         ~> lub_eqI
   811   is_lub_lub      ~> is_lubD2
   812   lubI            ~> is_lub_lub
   813   unique_lub      ~> is_lub_unique
   814   is_ub_lub       ~> is_lub_rangeD1
   815   lub_bin_chain   ~> is_lub_bin_chain
   816   lub_fun         ~> is_lub_fun
   817   thelub_fun      ~> lub_fun
   818   thelub_cfun     ~> lub_cfun
   819   thelub_Pair     ~> lub_Pair
   820   lub_cprod       ~> is_lub_prod
   821   thelub_cprod    ~> lub_prod
   822   minimal_cprod   ~> minimal_prod
   823   inst_cprod_pcpo ~> inst_prod_pcpo
   824   UU_I            ~> bottomI
   825   compact_UU      ~> compact_bottom
   826   deflation_UU    ~> deflation_bottom
   827   finite_deflation_UU ~> finite_deflation_bottom
   828 
   829 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
   830 
   831   sq_ord_less_eq_trans ~> below_eq_trans
   832   sq_ord_eq_less_trans ~> eq_below_trans
   833   refl_less            ~> below_refl
   834   trans_less           ~> below_trans
   835   antisym_less         ~> below_antisym
   836   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
   837   box_less             ~> box_below
   838   rev_trans_less       ~> rev_below_trans
   839   not_less2not_eq      ~> not_below2not_eq
   840   less_UU_iff          ~> below_UU_iff
   841   flat_less_iff        ~> flat_below_iff
   842   adm_less             ~> adm_below
   843   adm_not_less         ~> adm_not_below
   844   adm_compact_not_less ~> adm_compact_not_below
   845   less_fun_def         ~> below_fun_def
   846   expand_fun_less      ~> fun_below_iff
   847   less_fun_ext         ~> fun_belowI
   848   less_discr_def       ~> below_discr_def
   849   discr_less_eq        ~> discr_below_eq
   850   less_unit_def        ~> below_unit_def
   851   less_cprod_def       ~> below_prod_def
   852   prod_lessI           ~> prod_belowI
   853   Pair_less_iff        ~> Pair_below_iff
   854   fst_less_iff         ~> fst_below_iff
   855   snd_less_iff         ~> snd_below_iff
   856   expand_cfun_less     ~> cfun_below_iff
   857   less_cfun_ext        ~> cfun_belowI
   858   injection_less       ~> injection_below
   859   less_up_def          ~> below_up_def
   860   not_Iup_less         ~> not_Iup_below
   861   Iup_less             ~> Iup_below
   862   up_less              ~> up_below
   863   Def_inject_less_eq   ~> Def_below_Def
   864   Def_less_is_eq       ~> Def_below_iff
   865   spair_less_iff       ~> spair_below_iff
   866   less_sprod           ~> below_sprod
   867   spair_less           ~> spair_below
   868   sfst_less_iff        ~> sfst_below_iff
   869   ssnd_less_iff        ~> ssnd_below_iff
   870   fix_least_less       ~> fix_least_below
   871   dist_less_one        ~> dist_below_one
   872   less_ONE             ~> below_ONE
   873   ONE_less_iff         ~> ONE_below_iff
   874   less_sinlD           ~> below_sinlD
   875   less_sinrD           ~> below_sinrD
   876 
   877 
   878 *** FOL and ZF ***
   879 
   880 * All constant names are now qualified internally and use proper
   881 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
   882 
   883 
   884 *** ML ***
   885 
   886 * Antiquotation @{assert} inlines a function bool -> unit that raises
   887 Fail if the argument is false.  Due to inlining the source position of
   888 failed assertions is included in the error output.
   889 
   890 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
   891 text is in practice always evaluated with a stable theory checkpoint.
   892 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
   893 
   894 * Antiquotation @{theory A} refers to theory A from the ancestry of
   895 the current context, not any accidental theory loader state as before.
   896 Potential INCOMPATIBILITY, subtle change in semantics.
   897 
   898 * Syntax.pretty_priority (default 0) configures the required priority
   899 of pretty-printed output and thus affects insertion of parentheses.
   900 
   901 * Syntax.default_root (default "any") configures the inner syntax
   902 category (nonterminal symbol) for parsing of terms.
   903 
   904 * Former exception Library.UnequalLengths now coincides with
   905 ListPair.UnequalLengths.
   906 
   907 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
   908 main functionality is provided by structure Simplifier.
   909 
   910 * Renamed raw "explode" function to "raw_explode" to emphasize its
   911 meaning.  Note that internally to Isabelle, Symbol.explode is used in
   912 almost all situations.
   913 
   914 * Discontinued obsolete function sys_error and exception SYS_ERROR.
   915 See implementation manual for further details on exceptions in
   916 Isabelle/ML.
   917 
   918 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   919 meaning.
   920 
   921 * Renamed structure PureThy to Pure_Thy and moved most of its
   922 operations to structure Global_Theory, to emphasize that this is
   923 rarely-used global-only stuff.
   924 
   925 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
   926 instead (or tracing for high-volume output).
   927 
   928 * Configuration option show_question_marks only affects regular pretty
   929 printing of types and terms, not raw Term.string_of_vname.
   930 
   931 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
   932 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
   933 @{thms} for most purposes.
   934 
   935 * ML structure Unsynchronized is never opened, not even in Isar
   936 interaction mode as before.  Old Unsynchronized.set etc. have been
   937 discontinued -- use plain := instead.  This should be *rare* anyway,
   938 since modern tools always work via official context data, notably
   939 configuration options.
   940 
   941 * Parallel and asynchronous execution requires special care concerning
   942 interrupts.  Structure Exn provides some convenience functions that
   943 avoid working directly with raw Interrupt.  User code must not absorb
   944 interrupts -- intermediate handling (for cleanup etc.) needs to be
   945 followed by re-raising of the original exception.  Another common
   946 source of mistakes are "handle _" patterns, which make the meaning of
   947 the program subject to physical effects of the environment.
   948 
   949 
   950 
   951 New in Isabelle2009-2 (June 2010)
   952 ---------------------------------
   953 
   954 *** General ***
   955 
   956 * Authentic syntax for *all* logical entities (type classes, type
   957 constructors, term constants): provides simple and robust
   958 correspondence between formal entities and concrete syntax.  Within
   959 the parse tree / AST representations, "constants" are decorated by
   960 their category (class, type, const) and spelled out explicitly with
   961 their full internal name.
   962 
   963 Substantial INCOMPATIBILITY concerning low-level syntax declarations
   964 and translations (translation rules and translation functions in ML).
   965 Some hints on upgrading:
   966 
   967   - Many existing uses of 'syntax' and 'translations' can be replaced
   968     by more modern 'type_notation', 'notation' and 'abbreviation',
   969     which are independent of this issue.
   970 
   971   - 'translations' require markup within the AST; the term syntax
   972     provides the following special forms:
   973 
   974       CONST c   -- produces syntax version of constant c from context
   975       XCONST c  -- literally c, checked as constant from context
   976       c         -- literally c, if declared by 'syntax'
   977 
   978     Plain identifiers are treated as AST variables -- occasionally the
   979     system indicates accidental variables via the error "rhs contains
   980     extra variables".
   981 
   982     Type classes and type constructors are marked according to their
   983     concrete syntax.  Some old translations rules need to be written
   984     for the "type" category, using type constructor application
   985     instead of pseudo-term application of the default category
   986     "logic".
   987 
   988   - 'parse_translation' etc. in ML may use the following
   989     antiquotations:
   990 
   991       @{class_syntax c}   -- type class c within parse tree / AST
   992       @{term_syntax c}    -- type constructor c within parse tree / AST
   993       @{const_syntax c}   -- ML version of "CONST c" above
   994       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
   995 
   996   - Literal types within 'typed_print_translations', i.e. those *not*
   997     represented as pseudo-terms are represented verbatim.  Use @{class
   998     c} or @{type_name c} here instead of the above syntax
   999     antiquotations.
  1000 
  1001 Note that old non-authentic syntax was based on unqualified base
  1002 names, so all of the above "constant" names would coincide.  Recall
  1003 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
  1004 diagnose syntax problems.
  1005 
  1006 * Type constructors admit general mixfix syntax, not just infix.
  1007 
  1008 * Concrete syntax may be attached to local entities without a proof
  1009 body, too.  This works via regular mixfix annotations for 'fix',
  1010 'def', 'obtain' etc. or via the explicit 'write' command, which is
  1011 similar to the 'notation' command in theory specifications.
  1012 
  1013 * Discontinued unnamed infix syntax (legacy feature for many years) --
  1014 need to specify constant name and syntax separately.  Internal ML
  1015 datatype constructors have been renamed from InfixName to Infix etc.
  1016 Minor INCOMPATIBILITY.
  1017 
  1018 * Schematic theorem statements need to be explicitly markup as such,
  1019 via commands 'schematic_lemma', 'schematic_theorem',
  1020 'schematic_corollary'.  Thus the relevance of the proof is made
  1021 syntactically clear, which impacts performance in a parallel or
  1022 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  1023 
  1024 * Use of cumulative prems via "!" in some proof methods has been
  1025 discontinued (old legacy feature).
  1026 
  1027 * References 'trace_simp' and 'debug_simp' have been replaced by
  1028 configuration options stored in the context. Enabling tracing (the
  1029 case of debugging is similar) in proofs works via
  1030 
  1031   using [[trace_simp = true]]
  1032 
  1033 Tracing is then active for all invocations of the simplifier in
  1034 subsequent goal refinement steps. Tracing may also still be enabled or
  1035 disabled via the ProofGeneral settings menu.
  1036 
  1037 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  1038 'hide_fact' replace the former 'hide' KIND command.  Minor
  1039 INCOMPATIBILITY.
  1040 
  1041 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  1042 more efficient than combinations with -q1 or -q2.
  1043 
  1044 
  1045 *** Pure ***
  1046 
  1047 * Proofterms record type-class reasoning explicitly, using the
  1048 "unconstrain" operation internally.  This eliminates all sort
  1049 constraints from a theorem and proof, introducing explicit
  1050 OFCLASS-premises.  On the proof term level, this operation is
  1051 automatically applied at theorem boundaries, such that closed proofs
  1052 are always free of sort constraints.  INCOMPATIBILITY for tools that
  1053 inspect proof terms.
  1054 
  1055 * Local theory specifications may depend on extra type variables that
  1056 are not present in the result type -- arguments TYPE('a) :: 'a itself
  1057 are added internally.  For example:
  1058 
  1059   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  1060 
  1061 * Predicates of locales introduced by classes carry a mandatory
  1062 "class" prefix.  INCOMPATIBILITY.
  1063 
  1064 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  1065 
  1066 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  1067 'class' instead.
  1068 
  1069 * Command 'code_reflect' allows to incorporate generated ML code into
  1070 runtime environment; replaces immature code_datatype antiquotation.
  1071 INCOMPATIBILITY.
  1072 
  1073 * Code generator: simple concept for abstract datatypes obeying
  1074 invariants.
  1075 
  1076 * Code generator: details of internal data cache have no impact on the
  1077 user space functionality any longer.
  1078 
  1079 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1080 subgoals.  This is more appropriate for interpretations with 'where'.
  1081 INCOMPATIBILITY.
  1082 
  1083 * Command 'example_proof' opens an empty proof body.  This allows to
  1084 experiment with Isar, without producing any persistent result.
  1085 
  1086 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1087 within a local theory context, with explicit checking of the
  1088 constructors involved (in contrast to the raw 'syntax' versions).
  1089 
  1090 * Commands 'types' and 'typedecl' now work within a local theory
  1091 context -- without introducing dependencies on parameters or
  1092 assumptions, which is not possible in Isabelle/Pure.
  1093 
  1094 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1095 within a local theory context.  Minor INCOMPATIBILITY.
  1096 
  1097 
  1098 *** HOL ***
  1099 
  1100 * Command 'typedef' now works within a local theory context -- without
  1101 introducing dependencies on parameters or assumptions, which is not
  1102 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1103 contain multiple interpretations of local typedefs (with different
  1104 non-emptiness proofs), even in a global theory context.
  1105 
  1106 * New package for quotient types.  Commands 'quotient_type' and
  1107 'quotient_definition' may be used for defining types and constants by
  1108 quotient constructions.  An example is the type of integers created by
  1109 quotienting pairs of natural numbers:
  1110 
  1111   fun
  1112     intrel :: "(nat * nat) => (nat * nat) => bool"
  1113   where
  1114     "intrel (x, y) (u, v) = (x + v = u + y)"
  1115 
  1116   quotient_type int = "nat * nat" / intrel
  1117     by (auto simp add: equivp_def expand_fun_eq)
  1118 
  1119   quotient_definition
  1120     "0::int" is "(0::nat, 0::nat)"
  1121 
  1122 The method "lifting" can be used to lift of theorems from the
  1123 underlying "raw" type to the quotient type.  The example
  1124 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1125 construction and provides a reasoning infrastructure for finite sets.
  1126 
  1127 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1128 clash with new theory Quotient in Main HOL.
  1129 
  1130 * Moved the SMT binding into the main HOL session, eliminating
  1131 separate HOL-SMT session.
  1132 
  1133 * List membership infix mem operation is only an input abbreviation.
  1134 INCOMPATIBILITY.
  1135 
  1136 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1137 for future developements; former Library/Word.thy is still present in
  1138 the AFP entry RSAPPS.
  1139 
  1140 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1141 longer shadowed.  INCOMPATIBILITY.
  1142 
  1143 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1144 INCOMPATIBILITY.
  1145 
  1146 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1147 INCOMPATIBILITY.
  1148 
  1149 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1150 instead.  INCOMPATIBILITY.
  1151 
  1152 * Dropped several real-specific versions of lemmas about floor and
  1153 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1154 instead.  INCOMPATIBILITY.
  1155 
  1156   floor_number_of_eq         ~> floor_number_of
  1157   le_floor_eq_number_of      ~> number_of_le_floor
  1158   le_floor_eq_zero           ~> zero_le_floor
  1159   le_floor_eq_one            ~> one_le_floor
  1160   floor_less_eq_number_of    ~> floor_less_number_of
  1161   floor_less_eq_zero         ~> floor_less_zero
  1162   floor_less_eq_one          ~> floor_less_one
  1163   less_floor_eq_number_of    ~> number_of_less_floor
  1164   less_floor_eq_zero         ~> zero_less_floor
  1165   less_floor_eq_one          ~> one_less_floor
  1166   floor_le_eq_number_of      ~> floor_le_number_of
  1167   floor_le_eq_zero           ~> floor_le_zero
  1168   floor_le_eq_one            ~> floor_le_one
  1169   floor_subtract_number_of   ~> floor_diff_number_of
  1170   floor_subtract_one         ~> floor_diff_one
  1171   ceiling_number_of_eq       ~> ceiling_number_of
  1172   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1173   ceiling_le_zero_eq         ~> ceiling_le_zero
  1174   ceiling_le_eq_one          ~> ceiling_le_one
  1175   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1176   less_ceiling_eq_zero       ~> zero_less_ceiling
  1177   less_ceiling_eq_one        ~> one_less_ceiling
  1178   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1179   ceiling_less_eq_zero       ~> ceiling_less_zero
  1180   ceiling_less_eq_one        ~> ceiling_less_one
  1181   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1182   le_ceiling_eq_zero         ~> zero_le_ceiling
  1183   le_ceiling_eq_one          ~> one_le_ceiling
  1184   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1185   ceiling_subtract_one       ~> ceiling_diff_one
  1186 
  1187 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1188 application of the various fold combinators on finite sets.
  1189 
  1190 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1191 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1192 implementation.  INCOMPATIBILTY.
  1193 
  1194 * Theory Library/Coinductive_List has been removed -- superseded by
  1195 AFP/thys/Coinductive.
  1196 
  1197 * Theory PReal, including the type "preal" and related operations, has
  1198 been removed.  INCOMPATIBILITY.
  1199 
  1200 * Real: new development using Cauchy Sequences.
  1201 
  1202 * Split off theory "Big_Operators" containing setsum, setprod,
  1203 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1204 
  1205 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1206 "Int" etc.  INCOMPATIBILITY.
  1207 
  1208 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1209 
  1210 * New set of rules "ac_simps" provides combined assoc / commute
  1211 rewrites for all interpretations of the appropriate generic locales.
  1212 
  1213 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1214 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1215 appropriate and more consistent names suitable for name prefixes
  1216 within the HOL theories.  INCOMPATIBILITY.
  1217 
  1218 * Some generic constants have been put to appropriate theories:
  1219   - less_eq, less: Orderings
  1220   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1221   - inverse, divide: Rings
  1222 INCOMPATIBILITY.
  1223 
  1224 * More consistent naming of type classes involving orderings (and
  1225 lattices):
  1226 
  1227     lower_semilattice                   ~> semilattice_inf
  1228     upper_semilattice                   ~> semilattice_sup
  1229 
  1230     dense_linear_order                  ~> dense_linorder
  1231 
  1232     pordered_ab_group_add               ~> ordered_ab_group_add
  1233     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1234     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1235     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1236     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1237     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1238     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1239     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1240     pordered_comm_ring                  ~> ordered_comm_ring
  1241     pordered_comm_semiring              ~> ordered_comm_semiring
  1242     pordered_ring                       ~> ordered_ring
  1243     pordered_ring_abs                   ~> ordered_ring_abs
  1244     pordered_semiring                   ~> ordered_semiring
  1245 
  1246     ordered_ab_group_add                ~> linordered_ab_group_add
  1247     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1248     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1249     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1250     ordered_field                       ~> linordered_field
  1251     ordered_field_no_lb                 ~> linordered_field_no_lb
  1252     ordered_field_no_ub                 ~> linordered_field_no_ub
  1253     ordered_field_dense_linear_order    ~> dense_linordered_field
  1254     ordered_idom                        ~> linordered_idom
  1255     ordered_ring                        ~> linordered_ring
  1256     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1257     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1258     ordered_ring_strict                 ~> linordered_ring_strict
  1259     ordered_semidom                     ~> linordered_semidom
  1260     ordered_semiring                    ~> linordered_semiring
  1261     ordered_semiring_1                  ~> linordered_semiring_1
  1262     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1263     ordered_semiring_strict             ~> linordered_semiring_strict
  1264 
  1265   The following slightly odd type classes have been moved to a
  1266   separate theory Library/Lattice_Algebras:
  1267 
  1268     lordered_ab_group_add               ~> lattice_ab_group_add
  1269     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1270     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1271     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1272     lordered_ring                       ~> lattice_ring
  1273 
  1274 INCOMPATIBILITY.
  1275 
  1276 * Refined field classes:
  1277   - classes division_ring_inverse_zero, field_inverse_zero,
  1278     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1279     subsumes former division_by_zero class;
  1280   - numerous lemmas have been ported from field to division_ring.
  1281 INCOMPATIBILITY.
  1282 
  1283 * Refined algebra theorem collections:
  1284   - dropped theorem group group_simps, use algebra_simps instead;
  1285   - dropped theorem group ring_simps, use field_simps instead;
  1286   - proper theorem collection field_simps subsumes former theorem
  1287     groups field_eq_simps and field_simps;
  1288   - dropped lemma eq_minus_self_iff which is a duplicate for
  1289     equal_neg_zero.
  1290 INCOMPATIBILITY.
  1291 
  1292 * Theory Finite_Set and List: some lemmas have been generalized from
  1293 sets to lattices:
  1294 
  1295   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1296   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1297   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1298   union_Union_fold_union        ~> sup_Sup_fold_sup
  1299   Inter_fold_inter              ~> Inf_fold_inf
  1300   Union_fold_union              ~> Sup_fold_sup
  1301   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1302   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1303   INTER_fold_inter              ~> INFI_fold_inf
  1304   UNION_fold_union              ~> SUPR_fold_sup
  1305 
  1306 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1307 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1308 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1309 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1310 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1311 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1312 
  1313 * Reorganized theory Multiset: swapped notation of pointwise and
  1314 multiset order:
  1315 
  1316   - pointwise ordering is instance of class order with standard syntax
  1317     <= and <;
  1318   - multiset ordering has syntax <=# and <#; partial order properties
  1319     are provided by means of interpretation with prefix
  1320     multiset_order;
  1321   - less duplication, less historical organization of sections,
  1322     conversion from associations lists to multisets, rudimentary code
  1323     generation;
  1324   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1325     if needed.
  1326 
  1327 Renamed:
  1328 
  1329   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1330   multi_count_ext  ~>  multiset_ext
  1331   diff_union_inverse2  ~>  diff_union_cancelR
  1332 
  1333 INCOMPATIBILITY.
  1334 
  1335 * Theory Permutation: replaced local "remove" by List.remove1.
  1336 
  1337 * Code generation: ML and OCaml code is decorated with signatures.
  1338 
  1339 * Theory List: added transpose.
  1340 
  1341 * Library/Nat_Bijection.thy is a collection of bijective functions
  1342 between nat and other types, which supersedes the older libraries
  1343 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1344 
  1345   Constants:
  1346   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1347   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1348   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1349   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1350   Countable.pair_encode           ~> prod_encode
  1351   NatIso.prod2nat                 ~> prod_encode
  1352   NatIso.nat2prod                 ~> prod_decode
  1353   NatIso.sum2nat                  ~> sum_encode
  1354   NatIso.nat2sum                  ~> sum_decode
  1355   NatIso.list2nat                 ~> list_encode
  1356   NatIso.nat2list                 ~> list_decode
  1357   NatIso.set2nat                  ~> set_encode
  1358   NatIso.nat2set                  ~> set_decode
  1359 
  1360   Lemmas:
  1361   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1362   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1363   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1364   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1365   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1366   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1367   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1368   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1369   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1370   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1371   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1372   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1373   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1374 
  1375 * Sledgehammer:
  1376   - Renamed ATP commands:
  1377     atp_info     ~> sledgehammer running_atps
  1378     atp_kill     ~> sledgehammer kill_atps
  1379     atp_messages ~> sledgehammer messages
  1380     atp_minimize ~> sledgehammer minimize
  1381     print_atps   ~> sledgehammer available_atps
  1382     INCOMPATIBILITY.
  1383   - Added user's manual ("isabelle doc sledgehammer").
  1384   - Added option syntax and "sledgehammer_params" to customize
  1385     Sledgehammer's behavior.  See the manual for details.
  1386   - Modified the Isar proof reconstruction code so that it produces
  1387     direct proofs rather than proofs by contradiction.  (This feature
  1388     is still experimental.)
  1389   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1390     full-typed mode.
  1391   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1392 
  1393 * Nitpick:
  1394   - Added and implemented "binary_ints" and "bits" options.
  1395   - Added "std" option and implemented support for nonstandard models.
  1396   - Added and implemented "finitize" option to improve the precision
  1397     of infinite datatypes based on a monotonicity analysis.
  1398   - Added support for quotient types.
  1399   - Added support for "specification" and "ax_specification"
  1400     constructs.
  1401   - Added support for local definitions (for "function" and
  1402     "termination" proofs).
  1403   - Added support for term postprocessors.
  1404   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1405   - Improved efficiency of "destroy_constrs" optimization.
  1406   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1407     record getters.
  1408   - Fixed soundness bug related to higher-order constructors.
  1409   - Fixed soundness bug when "full_descrs" is enabled.
  1410   - Improved precision of set constructs.
  1411   - Added "atoms" option.
  1412   - Added cache to speed up repeated Kodkod invocations on the same
  1413     problems.
  1414   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1415     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1416     "SAT4J_Light".  INCOMPATIBILITY.
  1417   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1418     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1419   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1420 
  1421 * Method "induct" now takes instantiations of the form t, where t is not
  1422   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1423   If this is not intended, t has to be enclosed in parentheses.
  1424   By default, the equalities generated by definitional instantiations
  1425   are pre-simplified, which may cause parameters of inductive cases
  1426   to disappear, or may even delete some of the inductive cases.
  1427   Use "induct (no_simp)" instead of "induct" to restore the old
  1428   behaviour. The (no_simp) option is also understood by the "cases"
  1429   and "nominal_induct" methods, which now perform pre-simplification, too.
  1430   INCOMPATIBILITY.
  1431 
  1432 
  1433 *** HOLCF ***
  1434 
  1435 * Variable names in lemmas generated by the domain package have
  1436 changed; the naming scheme is now consistent with the HOL datatype
  1437 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1438 
  1439 * The domain package no longer defines the function "foo_copy" for
  1440 recursive domain "foo".  The reach lemma is now stated directly in
  1441 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1442 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1443 
  1444 * Most definedness lemmas generated by the domain package (previously
  1445 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1446 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1447 Proofs that used definedness lemmas as intro rules may break,
  1448 potential INCOMPATIBILITY.
  1449 
  1450 * Induction and casedist rules generated by the domain package now
  1451 declare proper case_names (one called "bottom", and one named for each
  1452 constructor).  INCOMPATIBILITY.
  1453 
  1454 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1455 rules are generated for each domain, INCOMPATIBILITY.
  1456 
  1457   foo_bar.reach       ~> foo.reach  bar.reach
  1458   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1459 
  1460 * Some lemmas generated by the domain package have been renamed for
  1461 consistency with the datatype package, INCOMPATIBILITY.
  1462 
  1463   foo.ind        ~> foo.induct
  1464   foo.finite_ind ~> foo.finite_induct
  1465   foo.coind      ~> foo.coinduct
  1466   foo.casedist   ~> foo.exhaust
  1467   foo.exhaust    ~> foo.nchotomy
  1468 
  1469 * For consistency with other definition packages, the fixrec package
  1470 now generates qualified theorem names, INCOMPATIBILITY.
  1471 
  1472   foo_simps  ~> foo.simps
  1473   foo_unfold ~> foo.unfold
  1474   foo_induct ~> foo.induct
  1475 
  1476 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1477 method and internal fixrec proofs now use the default simpset instead.
  1478 INCOMPATIBILITY.
  1479 
  1480 * The "contlub" predicate has been removed.  Proof scripts should use
  1481 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1482 
  1483 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1484 
  1485 * The constants cpair, cfst, and csnd have been removed in favor of
  1486 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1487 
  1488 
  1489 *** ML ***
  1490 
  1491 * Antiquotations for basic formal entities:
  1492 
  1493     @{class NAME}         -- type class
  1494     @{class_syntax NAME}  -- syntax representation of the above
  1495 
  1496     @{type_name NAME}     -- logical type
  1497     @{type_abbrev NAME}   -- type abbreviation
  1498     @{nonterminal NAME}   -- type of concrete syntactic category
  1499     @{type_syntax NAME}   -- syntax representation of any of the above
  1500 
  1501     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1502     @{const_abbrev NAME}  -- abbreviated constant
  1503     @{const_syntax NAME}  -- syntax representation of any of the above
  1504 
  1505 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1506 syntax constant (cf. 'syntax' command).
  1507 
  1508 * Antiquotation @{make_string} inlines a function to print arbitrary
  1509 values similar to the ML toplevel.  The result is compiler dependent
  1510 and may fall back on "?" in certain situations.
  1511 
  1512 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1513 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1514 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1515 not work with the asynchronous Isar document model.
  1516 
  1517 * Configuration options now admit dynamic default values, depending on
  1518 the context or even global references.
  1519 
  1520 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1521 uses an efficient external library if available (for Poly/ML).
  1522 
  1523 * Renamed some important ML structures, while keeping the old names
  1524 for some time as aliases within the structure Legacy:
  1525 
  1526   OuterKeyword  ~>  Keyword
  1527   OuterLex      ~>  Token
  1528   OuterParse    ~>  Parse
  1529   OuterSyntax   ~>  Outer_Syntax
  1530   PrintMode     ~>  Print_Mode
  1531   SpecParse     ~>  Parse_Spec
  1532   ThyInfo       ~>  Thy_Info
  1533   ThyLoad       ~>  Thy_Load
  1534   ThyOutput     ~>  Thy_Output
  1535   TypeInfer     ~>  Type_Infer
  1536 
  1537 Note that "open Legacy" simplifies porting of sources, but forgetting
  1538 to remove it again will complicate porting again in the future.
  1539 
  1540 * Most operations that refer to a global context are named
  1541 accordingly, e.g. Simplifier.global_context or
  1542 ProofContext.init_global.  There are some situations where a global
  1543 context actually works, but under normal circumstances one needs to
  1544 pass the proper local context through the code!
  1545 
  1546 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1547 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1548 Pretty.pp argument to merge, which is absent in the standard
  1549 Theory_Data version.
  1550 
  1551 * Sorts.certify_sort and derived "cert" operations for types and terms
  1552 no longer minimize sorts.  Thus certification at the boundary of the
  1553 inference kernel becomes invariant under addition of class relations,
  1554 which is an important monotonicity principle.  Sorts are now minimized
  1555 in the syntax layer only, at the boundary between the end-user and the
  1556 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1557 explicitly in rare situations.
  1558 
  1559 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1560 emphasize that this is in no way a standard operation.
  1561 INCOMPATIBILITY.
  1562 
  1563 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1564 usual for resolution.  Rare INCOMPATIBILITY.
  1565 
  1566 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1567 to emphasize that these only work in a global situation (which is
  1568 quite rare).
  1569 
  1570 * Curried take and drop in library.ML; negative length is interpreted
  1571 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1572 
  1573 * Proof terms: type substitutions on proof constants now use canonical
  1574 order of type variables.  INCOMPATIBILITY for tools working with proof
  1575 terms.
  1576 
  1577 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1578 may no longer carry premises.  User-level specifications are
  1579 transformed accordingly by Thm.add_axiom/add_def.
  1580 
  1581 
  1582 *** System ***
  1583 
  1584 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1585 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1586 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1587 
  1588 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1589 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1590 respectively.
  1591 
  1592 * Old lib/scripts/polyml-platform is superseded by the
  1593 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1594 variant, even on a 64 bit machine.  The following example setting
  1595 prefers 64 bit if available:
  1596 
  1597   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1598 
  1599 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1600 Isabelle/Scala layer for advanced prover interaction and integration.
  1601 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1602 component.
  1603 
  1604 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1605 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1606 similar to the default assignment of the document preparation system
  1607 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1608 provides some operations for direct access to the font without asking
  1609 the user for manual installation.
  1610 
  1611 
  1612 
  1613 New in Isabelle2009-1 (December 2009)
  1614 -------------------------------------
  1615 
  1616 *** General ***
  1617 
  1618 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1619 one backslash should be used, even in ML sources.
  1620 
  1621 
  1622 *** Pure ***
  1623 
  1624 * Locale interpretation propagates mixins along the locale hierarchy.
  1625 The currently only available mixins are the equations used to map
  1626 local definitions to terms of the target domain of an interpretation.
  1627 
  1628 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1629 loc" to print all interpretations of locale "loc" in the theory.
  1630 Interpretations in proofs are not shown.
  1631 
  1632 * Thoroughly revised locales tutorial.  New section on conditional
  1633 interpretation.
  1634 
  1635 * On instantiation of classes, remaining undefined class parameters
  1636 are formally declared.  INCOMPATIBILITY.
  1637 
  1638 
  1639 *** Document preparation ***
  1640 
  1641 * New generalized style concept for printing terms: @{foo (style) ...}
  1642 instead of @{foo_style style ...}  (old form is still retained for
  1643 backward compatibility).  Styles can be also applied for
  1644 antiquotations prop, term_type and typeof.
  1645 
  1646 
  1647 *** HOL ***
  1648 
  1649 * New proof method "smt" for a combination of first-order logic with
  1650 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1651 fixed-size bitvectors; there is also basic support for higher-order
  1652 features (esp. lambda abstractions).  It is an incomplete decision
  1653 procedure based on external SMT solvers using the oracle mechanism;
  1654 for the SMT solver Z3, this method is proof-producing.  Certificates
  1655 are provided to avoid calling the external solvers solely for
  1656 re-checking proofs.  Due to a remote SMT service there is no need for
  1657 installing SMT solvers locally.  See src/HOL/SMT.
  1658 
  1659 * New commands to load and prove verification conditions generated by
  1660 the Boogie program verifier or derived systems (e.g. the Verifying C
  1661 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1662 
  1663 * New counterexample generator tool 'nitpick' based on the Kodkod
  1664 relational model finder.  See src/HOL/Tools/Nitpick and
  1665 src/HOL/Nitpick_Examples.
  1666 
  1667 * New commands 'code_pred' and 'values' to invoke the predicate
  1668 compiler and to enumerate values of inductive predicates.
  1669 
  1670 * A tabled implementation of the reflexive transitive closure.
  1671 
  1672 * New implementation of quickcheck uses generic code generator;
  1673 default generators are provided for all suitable HOL types, records
  1674 and datatypes.  Old quickcheck can be re-activated importing theory
  1675 Library/SML_Quickcheck.
  1676 
  1677 * New testing tool Mirabelle for automated proof tools.  Applies
  1678 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1679 every proof step in a theory.  To be used in batch mode via the
  1680 "mirabelle" utility.
  1681 
  1682 * New proof method "sos" (sum of squares) for nonlinear real
  1683 arithmetic (originally due to John Harison). It requires theory
  1684 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1685 works well in practice on quantifier-free real arithmetic with +, -,
  1686 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1687 inequalities between polynomials.  It makes use of external
  1688 semidefinite programming solvers.  Method "sos" generates a
  1689 certificate that can be pasted into the proof thus avoiding the need
  1690 to call an external tool every time the proof is checked.  See
  1691 src/HOL/Library/Sum_Of_Squares.
  1692 
  1693 * New method "linarith" invokes existing linear arithmetic decision
  1694 procedure only.
  1695 
  1696 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1697 
  1698 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1699 Causes full type information to be output to the ATPs.  This slows
  1700 ATPs down considerably but eliminates a source of unsound "proofs"
  1701 that fail later.
  1702 
  1703 * New method "metisFT": A version of metis that uses full type
  1704 information in order to avoid failures of proof reconstruction.
  1705 
  1706 * New evaluator "approximate" approximates an real valued term using
  1707 the same method as the approximation method.
  1708 
  1709 * Method "approximate" now supports arithmetic expressions as
  1710 boundaries of intervals and implements interval splitting and Taylor
  1711 series expansion.
  1712 
  1713 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1714 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1715 
  1716 * New theory SupInf of the supremum and infimum operators for sets of
  1717 reals.
  1718 
  1719 * New theory Probability, which contains a development of measure
  1720 theory, eventually leading to Lebesgue integration and probability.
  1721 
  1722 * Extended Multivariate Analysis to include derivation and Brouwer's
  1723 fixpoint theorem.
  1724 
  1725 * Reorganization of number theory, INCOMPATIBILITY:
  1726   - new number theory development for nat and int, in theories Divides
  1727     and GCD as well as in new session Number_Theory
  1728   - some constants and facts now suffixed with _nat and _int
  1729     accordingly
  1730   - former session NumberTheory now named Old_Number_Theory, including
  1731     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1732   - moved theory Pocklington from src/HOL/Library to
  1733     src/HOL/Old_Number_Theory
  1734 
  1735 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1736 lcm of finite and infinite sets. It is shown that they form a complete
  1737 lattice.
  1738 
  1739 * Class semiring_div requires superclass no_zero_divisors and proof of
  1740 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1741 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1742 generalized to class semiring_div, subsuming former theorems
  1743 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1744 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1745 INCOMPATIBILITY.
  1746 
  1747 * Refinements to lattice classes and sets:
  1748   - less default intro/elim rules in locale variant, more default
  1749     intro/elim rules in class variant: more uniformity
  1750   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1751     le_inf_iff
  1752   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1753     sup_aci)
  1754   - renamed ACI to inf_sup_aci
  1755   - new class "boolean_algebra"
  1756   - class "complete_lattice" moved to separate theory
  1757     "Complete_Lattice"; corresponding constants (and abbreviations)
  1758     renamed and with authentic syntax:
  1759     Set.Inf ~>    Complete_Lattice.Inf
  1760     Set.Sup ~>    Complete_Lattice.Sup
  1761     Set.INFI ~>   Complete_Lattice.INFI
  1762     Set.SUPR ~>   Complete_Lattice.SUPR
  1763     Set.Inter ~>  Complete_Lattice.Inter
  1764     Set.Union ~>  Complete_Lattice.Union
  1765     Set.INTER ~>  Complete_Lattice.INTER
  1766     Set.UNION ~>  Complete_Lattice.UNION
  1767   - authentic syntax for
  1768     Set.Pow
  1769     Set.image
  1770   - mere abbreviations:
  1771     Set.empty               (for bot)
  1772     Set.UNIV                (for top)
  1773     Set.inter               (for inf, formerly Set.Int)
  1774     Set.union               (for sup, formerly Set.Un)
  1775     Complete_Lattice.Inter  (for Inf)
  1776     Complete_Lattice.Union  (for Sup)
  1777     Complete_Lattice.INTER  (for INFI)
  1778     Complete_Lattice.UNION  (for SUPR)
  1779   - object-logic definitions as far as appropriate
  1780 
  1781 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1782 Un_subset_iff are explicitly deleted as default simp rules; then also
  1783 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1784 deleted to achieve the desired effect.
  1785 
  1786 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1787 rules by default any longer; the same applies to min_max.inf_absorb1
  1788 etc.  INCOMPATIBILITY.
  1789 
  1790 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1791 pred_set_conv by default.  INCOMPATIBILITY.
  1792 
  1793 * Power operations on relations and functions are now one dedicated
  1794 constant "compow" with infix syntax "^^".  Power operation on
  1795 multiplicative monoids retains syntax "^" and is now defined generic
  1796 in class power.  INCOMPATIBILITY.
  1797 
  1798 * Relation composition "R O S" now has a more standard argument order:
  1799 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1800 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1801 break, since the O_assoc rule was not rewritten like this.  Fix using
  1802 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1803 
  1804 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1805 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1806 INCOMPATIBILITY.
  1807 
  1808 * Most rules produced by inductive and datatype package have mandatory
  1809 prefixes.  INCOMPATIBILITY.
  1810 
  1811 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1812 the attribute of the same name.  Each of the theorems in the list
  1813 DERIV_intros assumes composition with an additional function and
  1814 matches a variable to the derivative, which has to be solved by the
  1815 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1816 of most elementary terms.  Former Maclauren.DERIV_tac and
  1817 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1818 INCOMPATIBILITY.
  1819 
  1820 * Code generator attributes follow the usual underscore convention:
  1821     code_unfold     replaces    code unfold
  1822     code_post       replaces    code post
  1823     etc.
  1824   INCOMPATIBILITY.
  1825 
  1826 * Renamed methods:
  1827     sizechange -> size_change
  1828     induct_scheme -> induction_schema
  1829   INCOMPATIBILITY.
  1830 
  1831 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1832 INCOMPATIBILITY, use "undefined" directly.
  1833 
  1834 * Renamed theorems:
  1835     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1836     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1837     Suc_plus1 -> Suc_eq_plus1
  1838     *anti_sym -> *antisym*
  1839     vector_less_eq_def -> vector_le_def
  1840   INCOMPATIBILITY.
  1841 
  1842 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1843 INCOMPATIBILITY.
  1844 
  1845 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1846 INCOMPATIBILITY.
  1847 
  1848 
  1849 *** HOLCF ***
  1850 
  1851 * Theory Representable defines a class "rep" of domains that are
  1852 representable (via an ep-pair) in the universal domain type "udom".
  1853 Instances are provided for all type constructors defined in HOLCF.
  1854 
  1855 * The 'new_domain' command is a purely definitional version of the
  1856 domain package, for representable domains.  Syntax is identical to the
  1857 old domain package.  The 'new_domain' package also supports indirect
  1858 recursion using previously-defined type constructors.  See
  1859 src/HOLCF/ex/New_Domain.thy for examples.
  1860 
  1861 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1862 on the left-hand side of an equation, and then performs
  1863 simplification.  Rewriting is done using rules declared with the
  1864 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1865 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1866 
  1867 * The pattern-match compiler in 'fixrec' can now handle constructors
  1868 with HOL function types.  Pattern-match combinators for the Pair
  1869 constructor are pre-configured.
  1870 
  1871 * The 'fixrec' package now produces better fixed-point induction rules
  1872 for mutually-recursive definitions:  Induction rules have conclusions
  1873 of the form "P foo bar" instead of "P <foo, bar>".
  1874 
  1875 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1876 been renamed to "below".  The name "below" now replaces "less" in many
  1877 theorem names.  (Legacy theorem names using "less" are still supported
  1878 as well.)
  1879 
  1880 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1881 patterns can be used to generate strictness rules, or to make
  1882 functions more strict (much like the bang-patterns supported by the
  1883 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1884 examples.
  1885 
  1886 
  1887 *** ML ***
  1888 
  1889 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1890 errors and run-time exceptions, including detailed source positions.
  1891 
  1892 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1893 identified entries, with some additional information such as source
  1894 position, logical grouping etc.
  1895 
  1896 * Theory and context data is now introduced by the simplified and
  1897 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1898 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1899 copy operation) is still available for some time.
  1900 
  1901 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1902 provides a high-level programming interface to synchronized state
  1903 variables with atomic update.  This works via pure function
  1904 application within a critical section -- its runtime should be as
  1905 short as possible; beware of deadlocks if critical code is nested,
  1906 either directly or indirectly via other synchronized variables!
  1907 
  1908 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1909 wraps raw ML references, explicitly indicating their non-thread-safe
  1910 behaviour.  The Isar toplevel keeps this structure open, to
  1911 accommodate Proof General as well as quick and dirty interactive
  1912 experiments with references.
  1913 
  1914 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1915 parallel tactical reasoning.
  1916 
  1917 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1918 are similar to SUBPROOF, but are slightly more flexible: only the
  1919 specified parts of the subgoal are imported into the context, and the
  1920 body tactic may introduce new subgoals and schematic variables.
  1921 
  1922 * Old tactical METAHYPS, which does not observe the proof context, has
  1923 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1924 or Subgoal.FOCUS etc.
  1925 
  1926 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1927 functors have their own ML name space there is no point to mark them
  1928 separately.)  Minor INCOMPATIBILITY.
  1929 
  1930 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1931 
  1932 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1933 INCOMPATIBILITY.
  1934 
  1935 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1936 mode, which avoids critical setmp.
  1937 
  1938 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1939 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1940 Attrib/Method.setup introduced in Isabelle2009.
  1941 
  1942 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1943 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1944 last resort.  INCOMPATIBILITY.
  1945 
  1946 * Display.pretty_thm now requires a proper context (cf. former
  1947 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1948 or even Display.pretty_thm_without_context as last resort.
  1949 INCOMPATIBILITY.
  1950 
  1951 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1952 Syntax.pretty_typ/term directly, preferably with proper context
  1953 instead of global theory.
  1954 
  1955 
  1956 *** System ***
  1957 
  1958 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1959 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1960 usedir option -q.
  1961 
  1962 * Support for additional "Isabelle components" via etc/components, see
  1963 also the system manual.
  1964 
  1965 * The isabelle makeall tool now operates on all components with
  1966 IsaMakefile, not just hardwired "logics".
  1967 
  1968 * Removed "compress" option from isabelle-process and isabelle usedir;
  1969 this is always enabled.
  1970 
  1971 * Discontinued support for Poly/ML 4.x versions.
  1972 
  1973 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  1974 on a given logic image.  This requires the lighttpd webserver and is
  1975 currently supported on Linux only.
  1976 
  1977 
  1978 
  1979 New in Isabelle2009 (April 2009)
  1980 --------------------------------
  1981 
  1982 *** General ***
  1983 
  1984 * Simplified main Isabelle executables, with less surprises on
  1985 case-insensitive file-systems (such as Mac OS).
  1986 
  1987   - The main Isabelle tool wrapper is now called "isabelle" instead of
  1988     "isatool."
  1989 
  1990   - The former "isabelle" alias for "isabelle-process" has been
  1991     removed (should rarely occur to regular users).
  1992 
  1993   - The former "isabelle-interface" and its alias "Isabelle" have been
  1994     removed (interfaces are now regular Isabelle tools).
  1995 
  1996 Within scripts and make files, the Isabelle environment variables
  1997 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  1998 respectively.  (The latter are still available as legacy feature.)
  1999 
  2000 The old isabelle-interface wrapper could react in confusing ways if
  2001 the interface was uninstalled or changed otherwise.  Individual
  2002 interface tool configuration is now more explicit, see also the
  2003 Isabelle system manual.  In particular, Proof General is now available
  2004 via "isabelle emacs".
  2005 
  2006 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  2007 purge installed copies of Isabelle executables and re-run "isabelle
  2008 install -p ...", or use symlinks.
  2009 
  2010 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  2011 old ~/isabelle, which was slightly non-standard and apt to cause
  2012 surprises on case-insensitive file-systems (such as Mac OS).
  2013 
  2014 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  2015 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  2016 care is required when using older releases of Isabelle.  Note that
  2017 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  2018 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  2019 
  2020 * Proofs of fully specified statements are run in parallel on
  2021 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  2022 a regular 4-core machine, if the initial heap space is made reasonably
  2023 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  2024 
  2025 * The main reference manuals ("isar-ref", "implementation", and
  2026 "system") have been updated and extended.  Formally checked references
  2027 as hyperlinks are now available uniformly.
  2028 
  2029 
  2030 *** Pure ***
  2031 
  2032 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  2033 respects.  The most important changes are listed below.  See the
  2034 Tutorial on Locales ("locales" manual) for details.
  2035 
  2036 - In locale expressions, instantiation replaces renaming.  Parameters
  2037 must be declared in a for clause.  To aid compatibility with previous
  2038 parameter inheritance, in locale declarations, parameters that are not
  2039 'touched' (instantiation position "_" or omitted) are implicitly added
  2040 with their syntax at the beginning of the for clause.
  2041 
  2042 - Syntax from abbreviations and definitions in locales is available in
  2043 locale expressions and context elements.  The latter is particularly
  2044 useful in locale declarations.
  2045 
  2046 - More flexible mechanisms to qualify names generated by locale
  2047 expressions.  Qualifiers (prefixes) may be specified in locale
  2048 expressions, and can be marked as mandatory (syntax: "name!:") or
  2049 optional (syntax "name?:").  The default depends for plain "name:"
  2050 depends on the situation where a locale expression is used: in
  2051 commands 'locale' and 'sublocale' prefixes are optional, in
  2052 'interpretation' and 'interpret' prefixes are mandatory.  The old
  2053 implicit qualifiers derived from the parameter names of a locale are
  2054 no longer generated.
  2055 
  2056 - Command "sublocale l < e" replaces "interpretation l < e".  The
  2057 instantiation clause in "interpretation" and "interpret" (square
  2058 brackets) is no longer available.  Use locale expressions.
  2059 
  2060 - When converting proof scripts, mandatory qualifiers in
  2061 'interpretation' and 'interpret' should be retained by default, even
  2062 if this is an INCOMPATIBILITY compared to former behavior.  In the
  2063 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  2064 in locale expressions range over a single locale instance only.
  2065 
  2066 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  2067 In existing theorem specifications replace the includes element by the
  2068 respective context elements of the included locale, omitting those
  2069 that are already present in the theorem specification.  Multiple
  2070 assume elements of a locale should be replaced by a single one
  2071 involving the locale predicate.  In the proof body, declarations (most
  2072 notably theorems) may be regained by interpreting the respective
  2073 locales in the proof context as required (command "interpret").
  2074 
  2075 If using "includes" in replacement of a target solely because the
  2076 parameter types in the theorem are not as general as in the target,
  2077 consider declaring a new locale with additional type constraints on
  2078 the parameters (context element "constrains").
  2079 
  2080 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2081 
  2082 - Locale interpretation commands no longer attempt to simplify goal.
  2083 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2084 methods intro_locales and unfold_locales to clarify.
  2085 
  2086 - Locale interpretation commands no longer accept interpretation
  2087 attributes.  INCOMPATIBILITY.
  2088 
  2089 * Class declaration: so-called "base sort" must not be given in import
  2090 list any longer, but is inferred from the specification.  Particularly
  2091 in HOL, write
  2092 
  2093     class foo = ...
  2094 
  2095 instead of
  2096 
  2097     class foo = type + ...
  2098 
  2099 * Class target: global versions of theorems stemming do not carry a
  2100 parameter prefix any longer.  INCOMPATIBILITY.
  2101 
  2102 * Class 'instance' command no longer accepts attached definitions.
  2103 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2104 
  2105 * Recovered hiding of consts, which was accidentally broken in
  2106 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2107 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2108 
  2109 * Slightly more coherent Pure syntax, with updated documentation in
  2110 isar-ref manual.  Removed locales meta_term_syntax and
  2111 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2112 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2113 directly in regular applications.
  2114 
  2115 * There is a new syntactic category "float_const" for signed decimal
  2116 fractions (e.g. 123.45 or -123.45).
  2117 
  2118 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2119 interface with 'setup' command instead.
  2120 
  2121 * Command 'local_setup' is similar to 'setup', but operates on a local
  2122 theory context.
  2123 
  2124 * The 'axiomatization' command now only works within a global theory
  2125 context.  INCOMPATIBILITY.
  2126 
  2127 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2128 hypotheses.  Sorts required in the course of reasoning need to be
  2129 covered by the constraints in the initial statement, completed by the
  2130 type instance information of the background theory.  Non-trivial sort
  2131 hypotheses, which rarely occur in practice, may be specified via
  2132 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2133 
  2134   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2135 
  2136 The result contains an implicit sort hypotheses as before --
  2137 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2138 normalization.
  2139 
  2140 * Generalized Isar history, with support for linear undo, direct state
  2141 addressing etc.
  2142 
  2143 * Changed defaults for unify configuration options:
  2144 
  2145   unify_trace_bound = 50 (formerly 25)
  2146   unify_search_bound = 60 (formerly 30)
  2147 
  2148 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2149 
  2150   a) On theory merge, the last set of code equations for a particular
  2151      constant is taken (in accordance with the policy applied by other
  2152      parts of the code generator framework).
  2153 
  2154   b) Code equations stemming from explicit declarations (e.g. code
  2155      attribute) gain priority over default code equations stemming
  2156      from definition, primrec, fun etc.
  2157 
  2158 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2159 
  2160 * Unified theorem tables for both code generators.  Thus [code
  2161 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2162 
  2163 * Command 'find_consts' searches for constants based on type and name
  2164 patterns, e.g.
  2165 
  2166     find_consts "_ => bool"
  2167 
  2168 By default, matching is against subtypes, but it may be restricted to
  2169 the whole type.  Searching by name is possible.  Multiple queries are
  2170 conjunctive and queries may be negated by prefixing them with a
  2171 hyphen:
  2172 
  2173     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2174 
  2175 * New 'find_theorems' criterion "solves" matches theorems that
  2176 directly solve the current goal (modulo higher-order unification).
  2177 
  2178 * Auto solve feature for main theorem statements: whenever a new goal
  2179 is stated, "find_theorems solves" is called; any theorems that could
  2180 solve the lemma directly are listed as part of the goal state.
  2181 Cf. associated options in Proof General Isabelle settings menu,
  2182 enabled by default, with reasonable timeout for pathological cases of
  2183 higher-order unification.
  2184 
  2185 
  2186 *** Document preparation ***
  2187 
  2188 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2189 demanding keyword 'by' and supporting the full method expression
  2190 syntax just like the Isar command 'by'.
  2191 
  2192 
  2193 *** HOL ***
  2194 
  2195 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2196 points Main and Complex_Main remain as before.
  2197 
  2198 * Logic image HOL-Plain provides a minimal HOL with the most important
  2199 tools available (inductive, datatype, primrec, ...).  This facilitates
  2200 experimentation and tool development.  Note that user applications
  2201 (and library theories) should never refer to anything below theory
  2202 Main, as before.
  2203 
  2204 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2205 experimentation due to shorter build times.
  2206 
  2207 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2208 were previously part of former HOL-Complex.  Entry point Hyperreal
  2209 remains valid, but theories formerly using Complex_Main should now use
  2210 new entry point Hypercomplex.
  2211 
  2212 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2213 Posix processes.  Avoids potentially expensive forking of the ML
  2214 process.  New thread-based implementation also works on non-Unix
  2215 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2216 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2217 commands are covered in the isar-ref manual.
  2218 
  2219 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2220 sledgehammer without local ATP installation (Vampire etc.). Other
  2221 provers may be included via suitable ML wrappers, see also
  2222 src/HOL/ATP_Linkup.thy.
  2223 
  2224 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2225 menu.
  2226 
  2227 * The metis method no longer fails because the theorem is too trivial
  2228 (contains the empty clause).
  2229 
  2230 * The metis method now fails in the usual manner, rather than raising
  2231 an exception, if it determines that it cannot prove the theorem.
  2232 
  2233 * Method "coherent" implements a prover for coherent logic (see also
  2234 src/Tools/coherent.ML).
  2235 
  2236 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2237 "undefined" is the right choice to replace "arbitrary", though
  2238 logically there is no difference.  INCOMPATIBILITY.
  2239 
  2240 * Command "value" now integrates different evaluation mechanisms.  The
  2241 result of the first successful evaluation mechanism is printed.  In
  2242 square brackets a particular named evaluation mechanisms may be
  2243 specified (currently, [SML], [code] or [nbe]).  See further
  2244 src/HOL/ex/Eval_Examples.thy.
  2245 
  2246 * Normalization by evaluation now allows non-leftlinear equations.
  2247 Declare with attribute [code nbe].
  2248 
  2249 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2250 as the structured Isar versions "cases" and "induct", cf. the
  2251 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2252 are now presented as a list of individual projections
  2253 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2254 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2255 rare situations a different rule is selected --- notably nested tuple
  2256 elimination instead of former prod.exhaust: use explicit (case_tac t
  2257 rule: prod.exhaust) here.
  2258 
  2259 * Attributes "cases", "induct", "coinduct" support "del" option.
  2260 
  2261 * Removed fact "case_split_thm", which duplicates "case_split".
  2262 
  2263 * The option datatype has been moved to a new theory Option.  Renamed
  2264 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2265 
  2266 * New predicate "strict_mono" classifies strict functions on partial
  2267 orders.  With strict functions on linear orders, reasoning about
  2268 (in)equalities is facilitated by theorems "strict_mono_eq",
  2269 "strict_mono_less_eq" and "strict_mono_less".
  2270 
  2271 * Some set operations are now proper qualified constants with
  2272 authentic syntax.  INCOMPATIBILITY:
  2273 
  2274     op Int ~>   Set.Int
  2275     op Un ~>    Set.Un
  2276     INTER ~>    Set.INTER
  2277     UNION ~>    Set.UNION
  2278     Inter ~>    Set.Inter
  2279     Union ~>    Set.Union
  2280     {} ~>       Set.empty
  2281     UNIV ~>     Set.UNIV
  2282 
  2283 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2284 theory Set.
  2285 
  2286 * Auxiliary class "itself" has disappeared -- classes without any
  2287 parameter are treated as expected by the 'class' command.
  2288 
  2289 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2290 
  2291 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2292 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2293 
  2294 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2295 method "approximation".  It proves formulas on real values by using
  2296 interval arithmetic.  In the formulas are also the transcendental
  2297 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2298 allowed. For examples see
  2299 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2300 
  2301 * Theory "Reflection" now resides in HOL/Library.
  2302 
  2303 * Entry point to Word library now simply named "Word".
  2304 INCOMPATIBILITY.
  2305 
  2306 * Made source layout more coherent with logical distribution
  2307 structure:
  2308 
  2309     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2310     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2311     src/HOL/Library/GCD.thy ~> src/HOL/
  2312     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2313     src/HOL/Library/Parity.thy ~> src/HOL/
  2314     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2315     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2316     src/HOL/Real/Lubs.thy ~> src/HOL/
  2317     src/HOL/Real/PReal.thy ~> src/HOL/
  2318     src/HOL/Real/Rational.thy ~> src/HOL/
  2319     src/HOL/Real/RComplete.thy ~> src/HOL/
  2320     src/HOL/Real/RealDef.thy ~> src/HOL/
  2321     src/HOL/Real/RealPow.thy ~> src/HOL/
  2322     src/HOL/Real/Real.thy ~> src/HOL/
  2323     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2324     src/HOL/Complex/Complex.thy ~> src/HOL/
  2325     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2326     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2327     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2328     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2329     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2330     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2331     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2332     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2333     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2334     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2335     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2336     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2337     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2338     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2339     src/HOL/Real/Float ~> src/HOL/Library/
  2340     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2341     src/HOL/Real/RealVector.thy ~> src/HOL/
  2342 
  2343     src/HOL/arith_data.ML ~> src/HOL/Tools
  2344     src/HOL/hologic.ML ~> src/HOL/Tools
  2345     src/HOL/simpdata.ML ~> src/HOL/Tools
  2346     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2347     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2348     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2349     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2350     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2351     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2352     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2353 
  2354     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2355     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2356     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2357     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2358     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2359     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2360 
  2361 * If methods "eval" and "evaluation" encounter a structured proof
  2362 state with !!/==>, only the conclusion is evaluated to True (if
  2363 possible), avoiding strange error messages.
  2364 
  2365 * Method "sizechange" automates termination proofs using (a
  2366 modification of) the size-change principle.  Requires SAT solver.  See
  2367 src/HOL/ex/Termination.thy for examples.
  2368 
  2369 * Simplifier: simproc for let expressions now unfolds if bound
  2370 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2371 
  2372 * Method "arith": Linear arithmetic now ignores all inequalities when
  2373 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2374 
  2375 * New attribute "arith" for facts that should always be used
  2376 automatically by arithmetic. It is intended to be used locally in
  2377 proofs, e.g.
  2378 
  2379   assumes [arith]: "x > 0"
  2380 
  2381 Global usage is discouraged because of possible performance impact.
  2382 
  2383 * New classes "top" and "bot" with corresponding operations "top" and
  2384 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2385 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2386 
  2387 * Changed definition lemma "less_fun_def" in order to provide an
  2388 instance for preorders on functions; use lemma "less_le" instead.
  2389 INCOMPATIBILITY.
  2390 
  2391 * Theory Orderings: class "wellorder" moved here, with explicit
  2392 induction rule "less_induct" as assumption.  For instantiation of
  2393 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2394 INCOMPATIBILITY.
  2395 
  2396 * Theory Orderings: added class "preorder" as superclass of "order".
  2397 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2398 etc. slightly changed.  Some theorems named order_class.* now named
  2399 preorder_class.*.
  2400 
  2401 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2402 "diag" to "Id_on".
  2403 
  2404 * Theory Finite_Set: added a new fold combinator of type
  2405 
  2406   ('a => 'b => 'b) => 'b => 'a set => 'b
  2407 
  2408 Occasionally this is more convenient than the old fold combinator
  2409 which is now defined in terms of the new one and renamed to
  2410 fold_image.
  2411 
  2412 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2413 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2414 extended with further lemmas!).  At the moment both still exist but
  2415 the former will disappear at some point.
  2416 
  2417 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2418 class recpower.  Type-specific simp rules for various recpower types
  2419 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2420 
  2421 rat_power_0    -> power_0
  2422 rat_power_Suc  -> power_Suc
  2423 realpow_0      -> power_0
  2424 realpow_Suc    -> power_Suc
  2425 complexpow_0   -> power_0
  2426 complexpow_Suc -> power_Suc
  2427 power_poly_0   -> power_0
  2428 power_poly_Suc -> power_Suc
  2429 
  2430 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2431 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2432 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2433 of lemmas from Divides has been generalized from nat to class
  2434 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2435 renames resulting from duplicate elimination:
  2436 
  2437     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2438     zero_dvd_iff ~>         dvd_0_left_iff
  2439     dvd_0 ~>                dvd_0_right
  2440     DIVISION_BY_ZERO_DIV ~> div_by_0
  2441     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2442     mult_div ~>             div_mult_self2_is_id
  2443     mult_mod ~>             mod_mult_self2_is_0
  2444 
  2445 * Theory IntDiv: removed many lemmas that are instances of class-based
  2446 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2447 rename old lemmas as follows:
  2448 
  2449 dvd_diff               -> nat_dvd_diff
  2450 dvd_zminus_iff         -> dvd_minus_iff
  2451 mod_add1_eq            -> mod_add_eq
  2452 mod_mult1_eq           -> mod_mult_right_eq
  2453 mod_mult1_eq'          -> mod_mult_left_eq
  2454 mod_mult_distrib_mod   -> mod_mult_eq
  2455 nat_mod_add_left_eq    -> mod_add_left_eq
  2456 nat_mod_add_right_eq   -> mod_add_right_eq
  2457 nat_mod_div_trivial    -> mod_div_trivial
  2458 nat_mod_mod_trivial    -> mod_mod_trivial
  2459 zdiv_zadd_self1        -> div_add_self1
  2460 zdiv_zadd_self2        -> div_add_self2
  2461 zdiv_zmult_self1       -> div_mult_self2_is_id
  2462 zdiv_zmult_self2       -> div_mult_self1_is_id
  2463 zdvd_triv_left         -> dvd_triv_left
  2464 zdvd_triv_right        -> dvd_triv_right
  2465 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2466 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2467 zmod_zadd_left_eq      -> mod_add_left_eq
  2468 zmod_zadd_right_eq     -> mod_add_right_eq
  2469 zmod_zadd_self1        -> mod_add_self1
  2470 zmod_zadd_self2        -> mod_add_self2
  2471 zmod_zadd1_eq          -> mod_add_eq
  2472 zmod_zdiff1_eq         -> mod_diff_eq
  2473 zmod_zdvd_zmod         -> mod_mod_cancel
  2474 zmod_zmod_cancel       -> mod_mod_cancel
  2475 zmod_zmult_self1       -> mod_mult_self2_is_0
  2476 zmod_zmult_self2       -> mod_mult_self1_is_0
  2477 zmod_1                 -> mod_by_1
  2478 zdiv_1                 -> div_by_1
  2479 zdvd_abs1              -> abs_dvd_iff
  2480 zdvd_abs2              -> dvd_abs_iff
  2481 zdvd_refl              -> dvd_refl
  2482 zdvd_trans             -> dvd_trans
  2483 zdvd_zadd              -> dvd_add
  2484 zdvd_zdiff             -> dvd_diff
  2485 zdvd_zminus_iff        -> dvd_minus_iff
  2486 zdvd_zminus2_iff       -> minus_dvd_iff
  2487 zdvd_zmultD            -> dvd_mult_right
  2488 zdvd_zmultD2           -> dvd_mult_left
  2489 zdvd_zmult_mono        -> mult_dvd_mono
  2490 zdvd_0_right           -> dvd_0_right
  2491 zdvd_0_left            -> dvd_0_left_iff
  2492 zdvd_1_left            -> one_dvd
  2493 zminus_dvd_iff         -> minus_dvd_iff
  2494 
  2495 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2496 
  2497 * The real numbers offer decimal input syntax: 12.34 is translated
  2498 into 1234/10^2. This translation is not reversed upon output.
  2499 
  2500 * Theory Library/Polynomial defines an abstract type 'a poly of
  2501 univariate polynomials with coefficients of type 'a.  In addition to
  2502 the standard ring operations, it also supports div and mod.  Code
  2503 generation is also supported, using list-style constructors.
  2504 
  2505 * Theory Library/Inner_Product defines a class of real_inner for real
  2506 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2507 => real.  Class real_inner is a subclass of real_normed_vector from
  2508 theory RealVector.
  2509 
  2510 * Theory Library/Product_Vector provides instances for the product
  2511 type 'a * 'b of several classes from RealVector and Inner_Product.
  2512 Definitions of addition, subtraction, scalar multiplication, norms,
  2513 and inner products are included.
  2514 
  2515 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2516 addition to the field operations, numerals and case syntax are also
  2517 supported.
  2518 
  2519 * Theory Library/Diagonalize provides constructive version of Cantor's
  2520 first diagonalization argument.
  2521 
  2522 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2523 zlcm (for int); carried together from various gcd/lcm developements in
  2524 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2525 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2526 may recover tupled syntax as follows:
  2527 
  2528     hide (open) const gcd
  2529     abbreviation gcd where
  2530       "gcd == (%(a, b). GCD.gcd a b)"
  2531     notation (output)
  2532       GCD.gcd ("gcd '(_, _')")
  2533 
  2534 The same works for lcm, zgcd, zlcm.
  2535 
  2536 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2537 instantiations for algebraic structures.  Removed some duplicate
  2538 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2539 
  2540 * ML antiquotation @{code} takes a constant as argument and generates
  2541 corresponding code in background and inserts name of the corresponding
  2542 resulting ML value/function/datatype constructor binding in place.
  2543 All occurrences of @{code} with a single ML block are generated
  2544 simultaneously.  Provides a generic and safe interface for
  2545 instrumentalizing code generation.  See
  2546 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2547 In future you ought to refrain from ad-hoc compiling generated SML
  2548 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2549 cannot refer to constants for which user-defined serializations are
  2550 set.  Refer to the corresponding ML counterpart directly in that
  2551 cases.
  2552 
  2553 * Command 'rep_datatype': instead of theorem names the command now
  2554 takes a list of terms denoting the constructors of the type to be
  2555 represented as datatype.  The characteristic theorems have to be
  2556 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2557 have disappeared in favour of existing ones:
  2558 
  2559     unit_induct                 ~> unit.induct
  2560     prod_induct                 ~> prod.induct
  2561     sum_induct                  ~> sum.induct
  2562     Suc_Suc_eq                  ~> nat.inject
  2563     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2564 
  2565 
  2566 *** HOL-Algebra ***
  2567 
  2568 * New locales for orders and lattices where the equivalence relation
  2569 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2570 locales use a record structure with field eq for the equivalence.
  2571 
  2572 * New theory of factorial domains.
  2573 
  2574 * Units_l_inv and Units_r_inv are now simp rules by default.
  2575 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2576 and/or r_inv will now also require deletion of these lemmas.
  2577 
  2578 * Renamed the following theorems, INCOMPATIBILITY:
  2579 
  2580 UpperD ~> Upper_memD
  2581 LowerD ~> Lower_memD
  2582 least_carrier ~> least_closed
  2583 greatest_carrier ~> greatest_closed
  2584 greatest_Lower_above ~> greatest_Lower_below
  2585 one_zero ~> carrier_one_zero
  2586 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2587 
  2588 
  2589 *** HOL-Nominal ***
  2590 
  2591 * Nominal datatypes can now contain type-variables.
  2592 
  2593 * Commands 'nominal_inductive' and 'equivariance' work with local
  2594 theory targets.
  2595 
  2596 * Nominal primrec can now works with local theory targets and its
  2597 specification syntax now conforms to the general format as seen in
  2598 'inductive' etc.
  2599 
  2600 * Method "perm_simp" honours the standard simplifier attributes
  2601 (no_asm), (no_asm_use) etc.
  2602 
  2603 * The new predicate #* is defined like freshness, except that on the
  2604 left hand side can be a set or list of atoms.
  2605 
  2606 * Experimental command 'nominal_inductive2' derives strong induction
  2607 principles for inductive definitions.  In contrast to
  2608 'nominal_inductive', which can only deal with a fixed number of
  2609 binders, it can deal with arbitrary expressions standing for sets of
  2610 atoms to be avoided.  The only inductive definition we have at the
  2611 moment that needs this generalisation is the typing rule for Lets in
  2612 the algorithm W:
  2613 
  2614  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2615  -----------------------------------------------------------------
  2616          Gamma |- Let x be t1 in t2 : T2
  2617 
  2618 In this rule one wants to avoid all the binders that are introduced by
  2619 "close Gamma T1".  We are looking for other examples where this
  2620 feature might be useful.  Please let us know.
  2621 
  2622 
  2623 *** HOLCF ***
  2624 
  2625 * Reimplemented the simplification procedure for proving continuity
  2626 subgoals.  The new simproc is extensible; users can declare additional
  2627 continuity introduction rules with the attribute [cont2cont].
  2628 
  2629 * The continuity simproc now uses a different introduction rule for
  2630 solving continuity subgoals on terms with lambda abstractions.  In
  2631 some rare cases the new simproc may fail to solve subgoals that the
  2632 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2633 Potential INCOMPATIBILITY.
  2634 
  2635 * Command 'fixrec': specification syntax now conforms to the general
  2636 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2637 examples.  INCOMPATIBILITY.
  2638 
  2639 
  2640 *** ZF ***
  2641 
  2642 * Proof of Zorn's Lemma for partial orders.
  2643 
  2644 
  2645 *** ML ***
  2646 
  2647 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2648 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2649 depends on multithreading, so timouts will not work before Poly/ML
  2650 5.2.1!
  2651 
  2652 * High-level support for concurrent ML programming, see
  2653 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2654 particularly convenient to organize independent functional
  2655 computations.  The concept of "synchronized variables" provides a
  2656 higher-order interface for components with shared state, avoiding the
  2657 delicate details of mutexes and condition variables.  (Requires
  2658 Poly/ML 5.2.1 or later.)
  2659 
  2660 * ML bindings produced via Isar commands are stored within the Isar
  2661 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2662 become thread-safe and work with undo as expected (concerning
  2663 top-level bindings, not side-effects on global references).
  2664 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2665 compiler at runtime; really global bindings need to be given outside a
  2666 theory.  (Requires Poly/ML 5.2 or later.)
  2667 
  2668 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2669 context.  Top-level ML bindings are stored within the proof context in
  2670 a purely sequential fashion, disregarding the nested proof structure.
  2671 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2672 proof.  (Requires Poly/ML 5.2 or later.)
  2673 
  2674 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2675 and Method.setup, as well as Isar commands 'attribute_setup' and
  2676 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2677 existing code accordingly, or use plain 'setup' together with old
  2678 Method.add_method.
  2679 
  2680 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2681 to 'a -> thm, while results are always tagged with an authentic oracle
  2682 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2683 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2684 accordingly.  Note that extra performance may be gained by producing
  2685 the cterm carefully, avoiding slow Thm.cterm_of.
  2686 
  2687 * Simplified interface for defining document antiquotations via
  2688 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2689 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2690 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2691 examples.
  2692 
  2693 * More systematic treatment of long names, abstract name bindings, and
  2694 name space operations.  Basic operations on qualified names have been
  2695 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2696 Long_Name.append.  Old type bstring has been mostly replaced by
  2697 abstract type binding (see structure Binding), which supports precise
  2698 qualification by packages and local theory targets, as well as proper
  2699 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2700 bstring values into Binding.name, or better pass through abstract
  2701 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2702 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2703 
  2704 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2705 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2706 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2707 
  2708 * Disposed old type and term read functions (Sign.read_def_typ,
  2709 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2710 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2711 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2712 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2713 resort for legacy applications.
  2714 
  2715 * Disposed old declarations, tactics, tactic combinators that refer to
  2716 the simpset or claset of an implicit theory (such as Addsimps,
  2717 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2718 embedded ML text, or local_simpset_of with a proper context passed as
  2719 explicit runtime argument.
  2720 
  2721 * Rules and tactics that read instantiations (read_instantiate,
  2722 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2723 context, which is required for parsing and type-checking.  Moreover,
  2724 the variables are specified as plain indexnames, not string encodings
  2725 thereof.  INCOMPATIBILITY.
  2726 
  2727 * Generic Toplevel.add_hook interface allows to analyze the result of
  2728 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2729 for theorem dependency output of transactions resulting in a new
  2730 theory state.
  2731 
  2732 * ML antiquotations: block-structured compilation context indicated by
  2733 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2734 
  2735   @{binding name}                         - basic name binding
  2736   @{let ?pat = term}                      - term abbreviation (HO matching)
  2737   @{note name = fact}                     - fact abbreviation
  2738   @{thm fact}                             - singleton fact (with attributes)
  2739   @{thms fact}                            - general fact (with attributes)
  2740   @{lemma prop by method}                 - singleton goal
  2741   @{lemma prop by meth1 meth2}            - singleton goal
  2742   @{lemma prop1 ... propN by method}      - general goal
  2743   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2744   @{lemma (open) ...}                     - open derivation
  2745 
  2746 
  2747 *** System ***
  2748 
  2749 * The Isabelle "emacs" tool provides a specific interface to invoke
  2750 Proof General / Emacs, with more explicit failure if that is not
  2751 installed (the old isabelle-interface script silently falls back on
  2752 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2753 installation location of the Proof General distribution.
  2754 
  2755 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2756 the Isabelle process into a JVM/Scala application.  See
  2757 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2758 process wrapper has been discontinued.)
  2759 
  2760 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2761 
  2762 * Various status messages (with exact source position information) are
  2763 emitted, if proper markup print mode is enabled.  This allows
  2764 user-interface components to provide detailed feedback on internal
  2765 prover operations.
  2766 
  2767 
  2768 
  2769 New in Isabelle2008 (June 2008)
  2770 -------------------------------
  2771 
  2772 *** General ***
  2773 
  2774 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2775 and updated, with formally checked references as hyperlinks.
  2776 
  2777 * Theory loader: use_thy (and similar operations) no longer set the
  2778 implicit ML context, which was occasionally hard to predict and in
  2779 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2780 provides a proper context already.
  2781 
  2782 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2783 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2784 'use' within a theory file will do the job.
  2785 
  2786 * Name space merge now observes canonical order, i.e. the second space
  2787 is inserted into the first one, while existing entries in the first
  2788 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2789 swap theory imports.
  2790 
  2791 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2792 INCOMPATIBILITY in identifier syntax etc.
  2793 
  2794 * Outer syntax: string tokens no longer admit escaped white space,
  2795 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2796 white space without escapes.
  2797 
  2798 * Outer syntax: string tokens may contain arbitrary character codes
  2799 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2800 "foo_bar".
  2801 
  2802 
  2803 *** Pure ***
  2804 
  2805 * Context-dependent token translations.  Default setup reverts locally
  2806 fixed variables, and adds hilite markup for undeclared frees.
  2807 
  2808 * Unused theorems can be found using the new command 'unused_thms'.
  2809 There are three ways of invoking it:
  2810 
  2811 (1) unused_thms
  2812      Only finds unused theorems in the current theory.
  2813 
  2814 (2) unused_thms thy_1 ... thy_n -
  2815      Finds unused theorems in the current theory and all of its ancestors,
  2816      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2817 
  2818 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2819      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2820      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2821      their ancestors.
  2822 
  2823 In order to increase the readability of the list produced by
  2824 unused_thms, theorems that have been created by a particular instance
  2825 of a theory command such as 'inductive' or 'function' are considered
  2826 to belong to the same "group", meaning that if at least one theorem in
  2827 this group is used, the other theorems in the same group are no longer
  2828 reported as unused.  Moreover, if all theorems in the group are
  2829 unused, only one theorem in the group is displayed.
  2830 
  2831 Note that proof objects have to be switched on in order for
  2832 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2833 usually the case when using Proof General with the default settings).
  2834 
  2835 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2836 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2837 duplicate fact bindings, or even accidental fact duplications.  Note
  2838 that tools may maintain dynamically scoped facts systematically, using
  2839 PureThy.add_thms_dynamic.
  2840 
  2841 * Command 'hide' now allows to hide from "fact" name space as well.
  2842 
  2843 * Eliminated destructive theorem database, simpset, claset, and
  2844 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2845 update of theories within ML code.
  2846 
  2847 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2848 INCOMPATIBILITY, object-logics depending on former Pure require
  2849 additional setup PureThy.old_appl_syntax_setup; object-logics
  2850 depending on former CPure need to refer to Pure.
  2851 
  2852 * Commands 'use' and 'ML' are now purely functional, operating on
  2853 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2854 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2855 INCOMPATIBILITY.
  2856 
  2857 * Command 'setup': discontinued implicit version with ML reference.
  2858 
  2859 * Instantiation target allows for simultaneous specification of class
  2860 instance operations together with an instantiation proof.
  2861 Type-checking phase allows to refer to class operations uniformly.
  2862 See src/HOL/Complex/Complex.thy for an Isar example and
  2863 src/HOL/Library/Eval.thy for an ML example.
  2864 
  2865 * Indexing of literal facts: be more serious about including only
  2866 facts from the visible specification/proof context, but not the
  2867 background context (locale etc.).  Affects `prop` notation and method
  2868 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2869 situations.
  2870 
  2871 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2872 "(open)" option, which used to expose internal bound variables to the
  2873 proof text.
  2874 
  2875 * Isar statements: removed obsolete case "rule_context".
  2876 INCOMPATIBILITY, better use explicit fixes/assumes.
  2877 
  2878 * Locale proofs: default proof step now includes 'unfold_locales';
  2879 hence 'proof' without argument may be used to unfold locale
  2880 predicates.
  2881 
  2882 
  2883 *** Document preparation ***
  2884 
  2885 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2886 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2887 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2888 spot); renamed link color from "darkblue" to "linkcolor" (default
  2889 value unchanged, can be redefined via \definecolor); no longer sets
  2890 "a4paper" option (unnecessary or even intrusive).
  2891 
  2892 * Antiquotation @{lemma A method} proves proposition A by the given
  2893 method (either a method name or a method name plus (optional) method
  2894 arguments in parentheses) and prints A just like @{prop A}.
  2895 
  2896 
  2897 *** HOL ***
  2898 
  2899 * New primrec package.  Specification syntax conforms in style to
  2900 definition/function/....  No separate induction rule is provided.  The
  2901 "primrec" command distinguishes old-style and new-style specifications
  2902 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2903 When adjusting theories, beware: constants stemming from new-style
  2904 primrec specifications have authentic syntax.
  2905 
  2906 * Metis prover is now an order of magnitude faster, and also works
  2907 with multithreading.
  2908 
  2909 * Metis: the maximum number of clauses that can be produced from a
  2910 theorem is now given by the attribute max_clauses.  Theorems that
  2911 exceed this number are ignored, with a warning printed.
  2912 
  2913 * Sledgehammer no longer produces structured proofs by default. To
  2914 enable, declare [[sledgehammer_full = true]].  Attributes
  2915 reconstruction_modulus, reconstruction_sorts renamed
  2916 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2917 
  2918 * Method "induct_scheme" derives user-specified induction rules
  2919 from well-founded induction and completeness of patterns. This factors
  2920 out some operations that are done internally by the function package
  2921 and makes them available separately.  See
  2922 src/HOL/ex/Induction_Scheme.thy for examples.
  2923 
  2924 * More flexible generation of measure functions for termination
  2925 proofs: Measure functions can be declared by proving a rule of the
  2926 form "is_measure f" and giving it the [measure_function] attribute.
  2927 The "is_measure" predicate is logically meaningless (always true), and
  2928 just guides the heuristic.  To find suitable measure functions, the
  2929 termination prover sets up the goal "is_measure ?f" of the appropriate
  2930 type and generates all solutions by prolog-style backwards proof using
  2931 the declared rules.
  2932 
  2933 This setup also deals with rules like 
  2934 
  2935   "is_measure f ==> is_measure (list_size f)"
  2936 
  2937 which accommodates nested datatypes that recurse through lists.
  2938 Similar rules are predeclared for products and option types.
  2939 
  2940 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2941 
  2942   INCOMPATIBILITIES:
  2943 
  2944   - Definitions of overloaded constants on sets have to be replaced by
  2945     definitions on => and bool.
  2946 
  2947   - Some definitions of overloaded operators on sets can now be proved
  2948     using the definitions of the operators on => and bool.  Therefore,
  2949     the following theorems have been renamed:
  2950 
  2951       subset_def   -> subset_eq
  2952       psubset_def  -> psubset_eq
  2953       set_diff_def -> set_diff_eq
  2954       Compl_def    -> Compl_eq
  2955       Sup_set_def  -> Sup_set_eq
  2956       Inf_set_def  -> Inf_set_eq
  2957       sup_set_def  -> sup_set_eq
  2958       inf_set_def  -> inf_set_eq
  2959 
  2960   - Due to the incompleteness of the HO unification algorithm, some
  2961     rules such as subst may require manual instantiation, if some of
  2962     the unknowns in the rule is a set.
  2963 
  2964   - Higher order unification and forward proofs:
  2965     The proof pattern
  2966 
  2967       have "P (S::'a set)" <...>
  2968       then have "EX S. P S" ..
  2969 
  2970     no longer works (due to the incompleteness of the HO unification
  2971     algorithm) and must be replaced by the pattern
  2972 
  2973       have "EX S. P S"
  2974       proof
  2975         show "P S" <...>
  2976       qed
  2977 
  2978   - Calculational reasoning with subst (or similar rules):
  2979     The proof pattern
  2980 
  2981       have "P (S::'a set)" <...>
  2982       also have "S = T" <...>
  2983       finally have "P T" .
  2984 
  2985     no longer works (for similar reasons as the previous example) and
  2986     must be replaced by something like
  2987 
  2988       have "P (S::'a set)" <...>
  2989       moreover have "S = T" <...>
  2990       ultimately have "P T" by simp
  2991 
  2992   - Tactics or packages written in ML code:
  2993     Code performing pattern matching on types via
  2994 
  2995       Type ("set", [T]) => ...
  2996 
  2997     must be rewritten. Moreover, functions like strip_type or
  2998     binder_types no longer return the right value when applied to a
  2999     type of the form
  3000 
  3001       T1 => ... => Tn => U => bool
  3002 
  3003     rather than
  3004 
  3005       T1 => ... => Tn => U set
  3006 
  3007 * Merged theories Wellfounded_Recursion, Accessible_Part and
  3008 Wellfounded_Relations to theory Wellfounded.
  3009 
  3010 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  3011 
  3012 * Class finite no longer treats UNIV as class parameter.  Use class
  3013 enum from theory Library/Enum instead to achieve a similar effect.
  3014 INCOMPATIBILITY.
  3015 
  3016 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  3017 and "Cons".  INCOMPATIBILITY.
  3018 
  3019 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  3020 Potential INCOMPATIBILITY.
  3021 
  3022 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  3023 injective_fst_snd removed, use split_eta and prod_eqI instead.
  3024 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  3025 
  3026 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  3027 the same name in theory Orderings:
  3028 
  3029   less_trans
  3030   less_linear
  3031   le_imp_less_or_eq
  3032   le_less_trans
  3033   less_le_trans
  3034   less_not_sym
  3035   less_asym
  3036 
  3037 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  3038 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  3039 and different variable names.
  3040 
  3041 * Library/Option_ord.thy: Canonical order on option type.
  3042 
  3043 * Library/RBT.thy: Red-black trees, an efficient implementation of
  3044 finite maps.
  3045 
  3046 * Library/Countable.thy: Type class for countable types.
  3047 
  3048 * Theory Int: The representation of numerals has changed.  The infix
  3049 operator BIT and the bit datatype with constructors B0 and B1 have
  3050 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  3051 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  3052 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  3053 accordingly.
  3054 
  3055 * Theory Nat: definition of <= and < on natural numbers no longer
  3056 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  3057 le_def and less_def have disappeared.  Consider lemmas not_less
  3058 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  3059 
  3060 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  3061 (whose purpose mainly is for various fold_set functionals) have been
  3062 abandoned in favor of the existing algebraic classes
  3063 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  3064 lower_semilattice (resp. upper_semilattice) and linorder.
  3065 INCOMPATIBILITY.
  3066 
  3067 * Theory Transitive_Closure: induct and cases rules now declare proper
  3068 case_names ("base" and "step").  INCOMPATIBILITY.
  3069 
  3070 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  3071 lattices.  The form set-specific version is available as
  3072 Inductive.lfp_ordinal_induct_set.
  3073 
  3074 * Renamed theorems "power.simps" to "power_int.simps".
  3075 INCOMPATIBILITY.
  3076 
  3077 * Class semiring_div provides basic abstract properties of semirings
  3078 with division and modulo operations.  Subsumes former class dvd_mod.
  3079 
  3080 * Merged theories IntDef, Numeral and IntArith into unified theory
  3081 Int.  INCOMPATIBILITY.
  3082 
  3083 * Theory Library/Code_Index: type "index" now represents natural
  3084 numbers rather than integers.  INCOMPATIBILITY.
  3085 
  3086 * New class "uminus" with operation "uminus" (split of from class
  3087 "minus" which now only has operation "minus", binary).
  3088 INCOMPATIBILITY.
  3089 
  3090 * Constants "card", "internal_split", "option_map" now with authentic
  3091 syntax.  INCOMPATIBILITY.
  3092 
  3093 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3094 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3095 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3096 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3097 Sup_set_def, le_def, less_def, option_map_def now with object
  3098 equality.  INCOMPATIBILITY.
  3099 
  3100 * Records. Removed K_record, and replaced it by pure lambda term
  3101 %x. c. The simplifier setup is now more robust against eta expansion.
  3102 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3103 
  3104 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3105 
  3106 * Library/ListVector: new theory of arithmetic vector operations.
  3107 
  3108 * Library/Order_Relation: new theory of various orderings as sets of
  3109 pairs.  Defines preorders, partial orders, linear orders and
  3110 well-orders on sets and on types.
  3111 
  3112 
  3113 *** ZF ***
  3114 
  3115 * Renamed some theories to allow to loading both ZF and HOL in the
  3116 same session:
  3117 
  3118   Datatype  -> Datatype_ZF
  3119   Inductive -> Inductive_ZF
  3120   Int       -> Int_ZF
  3121   IntDiv    -> IntDiv_ZF
  3122   Nat       -> Nat_ZF
  3123   List      -> List_ZF
  3124   Main      -> Main_ZF
  3125 
  3126 INCOMPATIBILITY: ZF theories that import individual theories below
  3127 Main might need to be adapted.  Regular theory Main is still
  3128 available, as trivial extension of Main_ZF.
  3129 
  3130 
  3131 *** ML ***
  3132 
  3133 * ML within Isar: antiquotation @{const name} or @{const
  3134 name(typargs)} produces statically-checked Const term.
  3135 
  3136 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3137 (of the same name).  Removed obsolete print command.
  3138 
  3139 * Removed obsolete "use_legacy_bindings" function.
  3140 
  3141 * The ``print mode'' is now a thread-local value derived from a global
  3142 template (the former print_mode reference), thus access becomes
  3143 non-critical.  The global print_mode reference is for session
  3144 management only; user-code should use print_mode_value,
  3145 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3146 
  3147 * Functions system/system_out provide a robust way to invoke external
  3148 shell commands, with propagation of interrupts (requires Poly/ML
  3149 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3150 
  3151 
  3152 *** System ***
  3153 
  3154 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3155 in accordance with Proof General 3.7, which prefers GNU emacs.
  3156 
  3157 * isatool tty runs Isabelle process with plain tty interaction;
  3158 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3159 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3160 
  3161 * isatool browser now works with Cygwin as well, using general
  3162 "javapath" function defined in Isabelle process environment.
  3163 
  3164 * YXML notation provides a simple and efficient alternative to
  3165 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3166 isatool yxml as described in the Isabelle system manual.
  3167 
  3168 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3169 provides general wrapper for managing an Isabelle process in a robust
  3170 fashion, with ``cooked'' output from stdin/stderr.
  3171 
  3172 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3173 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3174 
  3175 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3176 way of changing the user's settings is via
  3177 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3178 script.
  3179 
  3180 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3181 cores of the underlying machine, which is a good starting point for
  3182 optimal performance tuning.  The corresponding usedir option -M allows
  3183 "max" as an alias for "0".  WARNING: does not work on certain versions
  3184 of Mac OS (with Poly/ML 5.1).
  3185 
  3186 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3187 adverse effect of Isabelle flooding interactive front-ends (notably
  3188 ProofGeneral / XEmacs).
  3189 
  3190 
  3191 
  3192 New in Isabelle2007 (November 2007)
  3193 -----------------------------------
  3194 
  3195 *** General ***
  3196 
  3197 * More uniform information about legacy features, notably a
  3198 warning/error of "Legacy feature: ...", depending on the state of the
  3199 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3200 legacy features will disappear eventually.
  3201 
  3202 * Theory syntax: the header format ``theory A = B + C:'' has been
  3203 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3204 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3205 
  3206 * Theory syntax: the old non-Isar theory file format has been
  3207 discontinued altogether.  Note that ML proof scripts may still be used
  3208 with Isar theories; migration is usually quite simple with the ML
  3209 function use_legacy_bindings.  INCOMPATIBILITY.
  3210 
  3211 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3212 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3213 quotes.
  3214 
  3215 * Theory loader: be more serious about observing the static theory
  3216 header specifications (including optional directories), but not the
  3217 accidental file locations of previously successful loads.  The strict
  3218 update policy of former update_thy is now already performed by
  3219 use_thy, so the former has been removed; use_thys updates several
  3220 theories simultaneously, just as 'imports' within a theory header
  3221 specification, but without merging the results.  Potential
  3222 INCOMPATIBILITY: may need to refine theory headers and commands
  3223 ROOT.ML which depend on load order.
  3224 
  3225 * Theory loader: optional support for content-based file
  3226 identification, instead of the traditional scheme of full physical
  3227 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3228 (cf. the system manual).  The new scheme allows to work with
  3229 non-finished theories in persistent session images, such that source
  3230 files may be moved later on without requiring reloads.
  3231 
  3232 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3233 file (with the same base name as the theory) are considered a legacy
  3234 feature, which will disappear eventually. Even now, the theory loader
  3235 no longer maintains dependencies on such files.
  3236 
  3237 * Syntax: the scope for resolving ambiguities via type-inference is
  3238 now limited to individual terms, instead of whole simultaneous
  3239 specifications as before. This greatly reduces the complexity of the
  3240 syntax module and improves flexibility by separating parsing and
  3241 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3242 'fixes' etc.) are required in rare situations.
  3243 
  3244 * Syntax: constants introduced by new-style packages ('definition',
  3245 'abbreviation' etc.) are passed through the syntax module in
  3246 ``authentic mode''. This means that associated mixfix annotations
  3247 really stick to such constants, independently of potential name space
  3248 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3249 trees are represented slightly differently, may need to adapt syntax
  3250 translations accordingly. Use CONST marker in 'translations' and
  3251 @{const_syntax} antiquotation in 'parse_translation' etc.
  3252 
  3253 * Legacy goal package: reduced interface to the bare minimum required
  3254 to keep existing proof scripts running.  Most other user-level
  3255 functions are now part of the OldGoals structure, which is *not* open
  3256 by default (consider isatool expandshort before open OldGoals).
  3257 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3258 these tend to cause confusion about the actual goal (!) context being
  3259 used here, which is not necessarily the same as the_context().
  3260 
  3261 * Command 'find_theorems': supports "*" wild-card in "name:"
  3262 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3263 support a specific search form (see ProofGeneral/CHANGES).
  3264 
  3265 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3266 by default, which means that "prems" (and also "fixed variables") are
  3267 suppressed from proof state output.  Note that the ProofGeneral
  3268 settings mechanism allows to change and save options persistently, but
  3269 older versions of Isabelle will fail to start up if a negative prems
  3270 limit is imposed.
  3271 
  3272 * Local theory targets may be specified by non-nested blocks of
  3273 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3274 contain definitions, theorems etc., including any derived mechanism
  3275 that has been implemented on top of these primitives.  This concept
  3276 generalizes the existing ``theorem (in ...)'' towards more versatility
  3277 and scalability.
  3278 
  3279 * Proof General interface: proper undo of final 'end' command;
  3280 discontinued Isabelle/classic mode (ML proof scripts).
  3281 
  3282 
  3283 *** Document preparation ***
  3284 
  3285 * Added antiquotation @{theory name} which prints the given name,
  3286 after checking that it refers to a valid ancestor theory in the
  3287 current context.
  3288 
  3289 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3290 check the given source text as ML type/structure, printing verbatim.
  3291 
  3292 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3293 "c args == rhs" given in the current context.  (Any number of
  3294 arguments may be given on the LHS.)
  3295 
  3296 
  3297 *** Pure ***
  3298 
  3299 * The 'class' package offers a combination of axclass and locale to
  3300 achieve Haskell-like type classes in Isabelle.  Definitions and
  3301 theorems within a class context produce both relative results (with
  3302 implicit parameters according to the locale context), and polymorphic
  3303 constants with qualified polymorphism (according to the class
  3304 context).  Within the body context of a 'class' target, a separate
  3305 syntax layer ("user space type system") takes care of converting
  3306 between global polymorphic consts and internal locale representation.
  3307 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3308 "isatool doc classes" provides a tutorial.
  3309 
  3310 * Generic code generator framework allows to generate executable
  3311 code for ML and Haskell (including Isabelle classes).  A short usage
  3312 sketch:
  3313 
  3314     internal compilation:
  3315         export_code <list of constants (term syntax)> in SML
  3316     writing SML code to a file:
  3317         export_code <list of constants (term syntax)> in SML <filename>
  3318     writing OCaml code to a file:
  3319         export_code <list of constants (term syntax)> in OCaml <filename>
  3320     writing Haskell code to a bunch of files:
  3321         export_code <list of constants (term syntax)> in Haskell <filename>
  3322 
  3323     evaluating closed propositions to True/False using code generation:
  3324         method ``eval''
  3325 
  3326 Reasonable default setup of framework in HOL.
  3327 
  3328 Theorem attributs for selecting and transforming function equations theorems:
  3329 
  3330     [code fun]:        select a theorem as function equation for a specific constant
  3331     [code fun del]:    deselect a theorem as function equation for a specific constant
  3332     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3333     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3334 
  3335 User-defined serializations (target in {SML, OCaml, Haskell}):
  3336 
  3337     code_const <and-list of constants (term syntax)>
  3338       {(target) <and-list of const target syntax>}+
  3339 
  3340     code_type <and-list of type constructors>
  3341       {(target) <and-list of type target syntax>}+
  3342 
  3343     code_instance <and-list of instances>
  3344       {(target)}+
  3345         where instance ::= <type constructor> :: <class>
  3346 
  3347     code_class <and_list of classes>
  3348       {(target) <and-list of class target syntax>}+
  3349         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3350 
  3351 code_instance and code_class only are effective to target Haskell.
  3352 
  3353 For example usage see src/HOL/ex/Codegenerator.thy and
  3354 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3355 generation from Isabelle/HOL theories is available via "isatool doc
  3356 codegen".
  3357 
  3358 * Code generator: consts in 'consts_code' Isar commands are now
  3359 referred to by usual term syntax (including optional type
  3360 annotations).
  3361 
  3362 * Command 'no_translations' removes translation rules from theory
  3363 syntax.
  3364 
  3365 * Overloaded definitions are now actually checked for acyclic
  3366 dependencies.  The overloading scheme is slightly more general than
  3367 that of Haskell98, although Isabelle does not demand an exact
  3368 correspondence to type class and instance declarations.
  3369 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3370 exotic versions of overloading -- at the discretion of the user!
  3371 
  3372 Polymorphic constants are represented via type arguments, i.e. the
  3373 instantiation that matches an instance against the most general
  3374 declaration given in the signature.  For example, with the declaration
  3375 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3376 as c(nat).  Overloading is essentially simultaneous structural
  3377 recursion over such type arguments.  Incomplete specification patterns
  3378 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3379 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3380 Command 'print_theory' outputs the normalized system of recursive
  3381 equations, see section "definitions".
  3382 
  3383 * Configuration options are maintained within the theory or proof
  3384 context (with name and type bool/int/string), providing a very simple
  3385 interface to a poor-man's version of general context data.  Tools may
  3386 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3387 these values using Config.get etc.  Users may change options via an
  3388 associated attribute of the same name.  This form of context
  3389 declaration works particularly well with commands 'declare' or
  3390 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3391 very easy to avoid global references, which would not observe Isar
  3392 toplevel undo/redo and fail to work with multithreading.
  3393 
  3394 Various global ML references of Pure and HOL have been turned into
  3395 configuration options:
  3396 
  3397   Unify.search_bound		unify_search_bound
  3398   Unify.trace_bound		unify_trace_bound
  3399   Unify.trace_simp		unify_trace_simp
  3400   Unify.trace_types		unify_trace_types
  3401   Simplifier.simp_depth_limit	simp_depth_limit
  3402   Blast.depth_limit		blast_depth_limit
  3403   DatatypeProp.dtK		datatype_distinctness_limit
  3404   fast_arith_neq_limit  	fast_arith_neq_limit
  3405   fast_arith_split_limit	fast_arith_split_limit
  3406 
  3407 * Named collections of theorems may be easily installed as context
  3408 data using the functor NamedThmsFun (see also
  3409 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3410 attributes; there is also a toplevel print command.  This facility is
  3411 just a common case of general context data, which is the preferred way
  3412 for anything more complex than just a list of facts in canonical
  3413 order.
  3414 
  3415 * Isar: command 'declaration' augments a local theory by generic
  3416 declaration functions written in ML.  This enables arbitrary content
  3417 being added to the context, depending on a morphism that tells the
  3418 difference of the original declaration context wrt. the application
  3419 context encountered later on.
  3420 
  3421 * Isar: proper interfaces for simplification procedures.  Command
  3422 'simproc_setup' declares named simprocs (with match patterns, and body
  3423 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3424 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3425 
  3426 * Isar: an extra pair of brackets around attribute declarations
  3427 abbreviates a theorem reference involving an internal dummy fact,
  3428 which will be ignored later --- only the effect of the attribute on
  3429 the background context will persist.  This form of in-place
  3430 declarations is particularly useful with commands like 'declare' and
  3431 'using', for example ``have A using [[simproc a]] by simp''.
  3432 
  3433 * Isar: method "assumption" (and implicit closing of subproofs) now
  3434 takes simple non-atomic goal assumptions into account: after applying
  3435 an assumption as a rule the resulting subgoals are solved by atomic
  3436 assumption steps.  This is particularly useful to finish 'obtain'
  3437 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3438 without referring to the original premise "!!x. P x ==> thesis" in the
  3439 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3440 more permissive.
  3441 
  3442 * Isar: implicit use of prems from the Isar proof context is
  3443 considered a legacy feature.  Common applications like ``have A .''
  3444 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3445 referencing facts explicitly here improves readability and
  3446 maintainability of proof texts.
  3447 
  3448 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3449 the obtained context from the course of reasoning!  For example:
  3450 
  3451   assume "EX x y. A x & B y"   -- "any previous fact"
  3452   then guess x and y by clarify
  3453 
  3454 This technique is potentially adventurous, depending on the facts and
  3455 proof tools being involved here.
  3456 
  3457 * Isar: known facts from the proof context may be specified as literal
  3458 propositions, using ASCII back-quote syntax.  This works wherever
  3459 named facts used to be allowed so far, in proof commands, proof
  3460 methods, attributes etc.  Literal facts are retrieved from the context
  3461 according to unification of type and term parameters.  For example,
  3462 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3463 theorems in the current context, then these are valid literal facts:
  3464 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3465 
  3466 There is also a proof method "fact" which does the same composition
  3467 for explicit goal states, e.g. the following proof texts coincide with
  3468 certain special cases of literal facts:
  3469 
  3470   have "A" by fact                 ==  note `A`
  3471   have "A ==> B" by fact           ==  note `A ==> B`
  3472   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3473   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3474 
  3475 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3476 outer syntax.  Thus symbolic identifiers may be used without
  3477 additional white space in declarations like this: ``assume *: A''.
  3478 
  3479 * Isar: 'print_facts' prints all local facts of the current context,
  3480 both named and unnamed ones.
  3481 
  3482 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3483 
  3484   def x == "t" and y == "u"
  3485 
  3486 * Isar: added command 'unfolding', which is structurally similar to
  3487 'using', but affects both the goal state and facts by unfolding given
  3488 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3489 'unfolded' attribute may be replaced by first-class proof text.
  3490 
  3491 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3492 and command 'unfolding' now all support object-level equalities
  3493 (potentially conditional).  The underlying notion of rewrite rule is
  3494 analogous to the 'rule_format' attribute, but *not* that of the
  3495 Simplifier (which is usually more generous).
  3496 
  3497 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3498 premises of a theorem by n. Useful in conjunction with drule.
  3499 
  3500 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3501 method expression within a sandbox consisting of the first N
  3502 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3503 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3504 simplifies all new goals that emerge from applying rule foo to the
  3505 originally first one.
  3506 
  3507 * Isar: schematic goals are no longer restricted to higher-order
  3508 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3509 expected.
  3510 
  3511 * Isar: the conclusion of a long theorem statement is now either
  3512 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3513 (essentially a disjunction of cases with local parameters and
  3514 assumptions).  The latter allows to express general elimination rules
  3515 adequately; in this notation common elimination rules look like this:
  3516 
  3517   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3518     assumes "EX x. P x"
  3519     obtains x where "P x"
  3520 
  3521   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3522     assumes "A & B"
  3523     obtains A and B
  3524 
  3525   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3526     assumes "A | B"
  3527     obtains
  3528       A
  3529     | B
  3530 
  3531 The subsequent classical rules even refer to the formal "thesis"
  3532 explicitly:
  3533 
  3534   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3535     obtains "~ thesis"
  3536 
  3537   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3538     obtains "thesis ==> something"
  3539 
  3540 The actual proof of an 'obtains' statement is analogous to that of the
  3541 Isar proof element 'obtain', only that there may be several cases.
  3542 Optional case names may be specified in parentheses; these will be
  3543 available both in the present proof and as annotations in the
  3544 resulting rule, for later use with the 'cases' method (cf. attribute
  3545 case_names).
  3546 
  3547 * Isar: the assumptions of a long theorem statement are available as
  3548 "assms" fact in the proof context.  This is more appropriate than the
  3549 (historical) "prems", which refers to all assumptions of the current
  3550 context, including those from the target locale, proof body etc.
  3551 
  3552 * Isar: 'print_statement' prints theorems from the current theory or
  3553 proof context in long statement form, according to the syntax of a
  3554 top-level lemma.
  3555 
  3556 * Isar: 'obtain' takes an optional case name for the local context
  3557 introduction rule (default "that").
  3558 
  3559 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3560 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3561 to occur.
  3562 
  3563 * Pure: syntax "CONST name" produces a fully internalized constant
  3564 according to the current context.  This is particularly useful for
  3565 syntax translations that should refer to internal constant
  3566 representations independently of name spaces.
  3567 
  3568 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3569 instead of "FOO ". This allows multiple binder declarations to coexist
  3570 in the same context.  INCOMPATIBILITY.
  3571 
  3572 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3573 primitive that also works in a locale context (both for constants and
  3574 fixed variables). Type declaration and internal syntactic representation
  3575 of given constants retrieved from the context. Likewise, the
  3576 'no_notation' command allows to remove given syntax annotations from the
  3577 current context.
  3578 
  3579 * Isar/locales: new derived specification elements 'axiomatization',
  3580 'definition', 'abbreviation', which support type-inference, admit
  3581 object-level specifications (equality, equivalence).  See also the
  3582 isar-ref manual.  Examples:
  3583 
  3584   axiomatization
  3585     eq  (infix "===" 50) where
  3586     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3587 
  3588   definition "f x y = x + y + 1"
  3589   definition g where "g x = f x x"
  3590 
  3591   abbreviation
  3592     neq  (infix "=!=" 50) where
  3593     "x =!= y == ~ (x === y)"
  3594 
  3595 These specifications may be also used in a locale context.  Then the
  3596 constants being introduced depend on certain fixed parameters, and the
  3597 constant name is qualified by the locale base name.  An internal
  3598 abbreviation takes care for convenient input and output, making the
  3599 parameters implicit and using the original short name.  See also
  3600 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3601 entities from a monomorphic theory.
  3602 
  3603 Presently, abbreviations are only available 'in' a target locale, but
  3604 not inherited by general import expressions.  Also note that
  3605 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3606 'translations' in common applications.  The "no_abbrevs" print mode
  3607 prevents folding of abbreviations in term output.
  3608 
  3609 Concrete syntax is attached to specified constants in internal form,
  3610 independently of name spaces.  The parse tree representation is
  3611 slightly different -- use 'notation' instead of raw 'syntax', and
  3612 'translations' with explicit "CONST" markup to accommodate this.
  3613 
  3614 * Pure/Isar: unified syntax for new-style specification mechanisms
  3615 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3616 full type inference and dummy patterns ("_").  For example:
  3617 
  3618   definition "K x _ = x"
  3619 
  3620   inductive conj for A B
  3621   where "A ==> B ==> conj A B"
  3622 
  3623 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3624 the current context.  Print mode "no_abbrevs" prevents inversion of
  3625 abbreviations on output.
  3626 
  3627 * Isar/locales: improved parameter handling: use of locales "var" and
  3628 "struct" no longer necessary; - parameter renamings are no longer
  3629 required to be injective.  For example, this allows to define
  3630 endomorphisms as locale endom = homom mult mult h.
  3631 
  3632 * Isar/locales: changed the way locales with predicates are defined.
  3633 Instead of accumulating the specification, the imported expression is
  3634 now an interpretation.  INCOMPATIBILITY: different normal form of
  3635 locale expressions.  In particular, in interpretations of locales with
  3636 predicates, goals repesenting already interpreted fragments are not
  3637 removed automatically.  Use methods `intro_locales' and
  3638 `unfold_locales'; see below.
  3639 
  3640 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3641 provide backward reasoning on locales predicates.  The methods are
  3642 aware of interpretations and discharge corresponding goals.
  3643 `intro_locales' is less aggressive then `unfold_locales' and does not
  3644 unfold predicates to assumptions.
  3645 
  3646 * Isar/locales: the order in which locale fragments are accumulated
  3647 has changed.  This enables to override declarations from fragments due
  3648 to interpretations -- for example, unwanted simp rules.
  3649 
  3650 * Isar/locales: interpretation in theories and proof contexts has been
  3651 extended.  One may now specify (and prove) equations, which are
  3652 unfolded in interpreted theorems.  This is useful for replacing
  3653 defined concepts (constants depending on locale parameters) by
  3654 concepts already existing in the target context.  Example:
  3655 
  3656   interpretation partial_order ["op <= :: [int, int] => bool"]
  3657     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3658 
  3659 Typically, the constant `partial_order.less' is created by a
  3660 definition specification element in the context of locale
  3661 partial_order.
  3662 
  3663 * Method "induct": improved internal context management to support
  3664 local fixes and defines on-the-fly. Thus explicit meta-level
  3665 connectives !!  and ==> are rarely required anymore in inductive goals
  3666 (using object-logic connectives for this purpose has been long
  3667 obsolete anyway). Common proof patterns are explained in
  3668 src/HOL/Induct/Common_Patterns.thy, see also
  3669 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3670 examples.
  3671 
  3672 * Method "induct": improved handling of simultaneous goals. Instead of
  3673 introducing object-level conjunction, the statement is now split into
  3674 several conclusions, while the corresponding symbolic cases are nested
  3675 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3676 see src/HOL/Induct/Common_Patterns.thy, for example.
  3677 
  3678 * Method "induct": mutual induction rules are now specified as a list
  3679 of rule sharing the same induction cases. HOL packages usually provide
  3680 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3681 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3682 mutual induction rules differently, i.e. like this:
  3683 
  3684   (induct rule: foo_bar.inducts)
  3685   (induct set: foo bar)
  3686   (induct pred: foo bar)
  3687   (induct type: foo bar)
  3688 
  3689 The ML function ProjectRule.projections turns old-style rules into the
  3690 new format.
  3691 
  3692 * Method "coinduct": dual of induction, see
  3693 src/HOL/Library/Coinductive_List.thy for various examples.
  3694 
  3695 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3696 considered a legacy feature.
  3697 
  3698 * Attribute "symmetric" produces result with standardized schematic
  3699 variables (index 0).  Potential INCOMPATIBILITY.
  3700 
  3701 * Simplifier: by default the simplifier trace only shows top level
  3702 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3703 default. Thus there is less danger of being flooded by the trace. The
  3704 trace indicates where parts have been suppressed.
  3705   
  3706 * Provers/classical: removed obsolete classical version of elim_format
  3707 attribute; classical elim/dest rules are now treated uniformly when
  3708 manipulating the claset.
  3709 
  3710 * Provers/classical: stricter checks to ensure that supplied intro,
  3711 dest and elim rules are well-formed; dest and elim rules must have at
  3712 least one premise.
  3713 
  3714 * Provers/classical: attributes dest/elim/intro take an optional
  3715 weight argument for the rule (just as the Pure versions).  Weights are
  3716 ignored by automated tools, but determine the search order of single
  3717 rule steps.
  3718 
  3719 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3720 where the body does not mention the bound variable.  Note that dummy
  3721 patterns implicitly depend on their context of bounds, which makes
  3722 "{_. _}" match any set comprehension as expected.  Potential
  3723 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3724 constant "_idtdummy" in the binding position.
  3725 
  3726 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3727 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3728 for example "A -> B" => "Pi A (%_. B)".
  3729 
  3730 * Pure: 'class_deps' command visualizes the subclass relation, using
  3731 the graph browser tool.
  3732 
  3733 * Pure: 'print_theory' now suppresses certain internal declarations by
  3734 default; use '!' option for full details.
  3735 
  3736 
  3737 *** HOL ***
  3738 
  3739 * Method "metis" proves goals by applying the Metis general-purpose
  3740 resolution prover (see also http://gilith.com/software/metis/).
  3741 Examples are in the directory MetisExamples.  WARNING: the
  3742 Isabelle/HOL-Metis integration does not yet work properly with
  3743 multi-threading.
  3744   
  3745 * Command 'sledgehammer' invokes external automatic theorem provers as
  3746 background processes.  It generates calls to the "metis" method if
  3747 successful. These can be pasted into the proof.  Users do not have to
  3748 wait for the automatic provers to return.  WARNING: does not really
  3749 work with multi-threading.
  3750 
  3751 * New "auto_quickcheck" feature tests outermost goal statements for
  3752 potential counter-examples.  Controlled by ML references
  3753 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3754 5000 milliseconds).  Fails silently if statements is outside of
  3755 executable fragment, or any other codgenerator problem occurs.
  3756 
  3757 * New constant "undefined" with axiom "undefined x = undefined".
  3758 
  3759 * Added class "HOL.eq", allowing for code generation with polymorphic
  3760 equality.
  3761 
  3762 * Some renaming of class constants due to canonical name prefixing in
  3763 the new 'class' package:
  3764 
  3765     HOL.abs ~> HOL.abs_class.abs
  3766     HOL.divide ~> HOL.divide_class.divide
  3767     0 ~> HOL.zero_class.zero
  3768     1 ~> HOL.one_class.one
  3769     op + ~> HOL.plus_class.plus
  3770     op - ~> HOL.minus_class.minus
  3771     uminus ~> HOL.minus_class.uminus
  3772     op * ~> HOL.times_class.times
  3773     op < ~> HOL.ord_class.less
  3774     op <= > HOL.ord_class.less_eq
  3775     Nat.power ~> Power.power_class.power
  3776     Nat.size ~> Nat.size_class.size
  3777     Numeral.number_of ~> Numeral.number_class.number_of
  3778     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3779     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3780     Orderings.min ~> Orderings.ord_class.min
  3781     Orderings.max ~> Orderings.ord_class.max
  3782     Divides.op div ~> Divides.div_class.div
  3783     Divides.op mod ~> Divides.div_class.mod
  3784     Divides.op dvd ~> Divides.div_class.dvd
  3785 
  3786 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3787 
  3788 a) User-defined constants using any of the names "plus", "minus",
  3789 "times", "less" or "less_eq". The standard syntax translations for
  3790 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3791 names.
  3792 
  3793 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3794 INCOMPATIBILITY: use more specific names.
  3795 
  3796 c) Permutative equations (e.g. "a + b = b + a")
  3797 Since the change of names also changes the order of terms, permutative
  3798 rewrite rules may get applied in a different order. Experience shows
  3799 that this is rarely the case (only two adaptions in the whole Isabelle
  3800 distribution).  INCOMPATIBILITY: rewrite proofs
  3801 
  3802 d) ML code directly refering to constant names
  3803 This in general only affects hand-written proof tactics, simprocs and
  3804 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3805 Consider using @{const_name} antiquotation.
  3806 
  3807 * New class "default" with associated constant "default".
  3808 
  3809 * Function "sgn" is now overloaded and available on int, real, complex
  3810 (and other numeric types), using class "sgn".  Two possible defs of
  3811 sgn are given as equational assumptions in the classes sgn_if and
  3812 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3813 INCOMPATIBILITY.
  3814 
  3815 * Locale "partial_order" now unified with class "order" (cf. theory
  3816 Orderings), added parameter "less".  INCOMPATIBILITY.
  3817 
  3818 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3819 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3820 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3821 
  3822 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3823 changed order of proof goals in instance proofs.
  3824 
  3825 * The transitivity reasoner for partial and linear orders is set up
  3826 for classes "order" and "linorder".  Instances of the reasoner are available
  3827 in all contexts importing or interpreting the corresponding locales.
  3828 Method "order" invokes the reasoner separately; the reasoner
  3829 is also integrated with the Simplifier as a solver.  Diagnostic
  3830 command 'print_orders' shows the available instances of the reasoner
  3831 in the current context.
  3832 
  3833 * Localized monotonicity predicate in theory "Orderings"; integrated
  3834 lemmas max_of_mono and min_of_mono with this predicate.
  3835 INCOMPATIBILITY.
  3836 
  3837 * Formulation of theorem "dense" changed slightly due to integration
  3838 with new class dense_linear_order.
  3839 
  3840 * Uniform lattice theory development in HOL.
  3841 
  3842     constants "meet" and "join" now named "inf" and "sup"
  3843     constant "Meet" now named "Inf"
  3844 
  3845     classes "meet_semilorder" and "join_semilorder" now named
  3846       "lower_semilattice" and "upper_semilattice"
  3847     class "lorder" now named "lattice"
  3848     class "comp_lat" now named "complete_lattice"
  3849 
  3850     Instantiation of lattice classes allows explicit definitions
  3851     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3852 
  3853   INCOMPATIBILITY.  Theorem renames:
  3854 
  3855     meet_left_le            ~> inf_le1
  3856     meet_right_le           ~> inf_le2
  3857     join_left_le            ~> sup_ge1
  3858     join_right_le           ~> sup_ge2
  3859     meet_join_le            ~> inf_sup_ord
  3860     le_meetI                ~> le_infI
  3861     join_leI                ~> le_supI
  3862     le_meet                 ~> le_inf_iff
  3863     le_join                 ~> ge_sup_conv
  3864     meet_idempotent         ~> inf_idem
  3865     join_idempotent         ~> sup_idem
  3866     meet_comm               ~> inf_commute
  3867     join_comm               ~> sup_commute
  3868     meet_leI1               ~> le_infI1
  3869     meet_leI2               ~> le_infI2
  3870     le_joinI1               ~> le_supI1
  3871     le_joinI2               ~> le_supI2
  3872     meet_assoc              ~> inf_assoc
  3873     join_assoc              ~> sup_assoc
  3874     meet_left_comm          ~> inf_left_commute
  3875     meet_left_idempotent    ~> inf_left_idem
  3876     join_left_comm          ~> sup_left_commute
  3877     join_left_idempotent    ~> sup_left_idem
  3878     meet_aci                ~> inf_aci
  3879     join_aci                ~> sup_aci
  3880     le_def_meet             ~> le_iff_inf
  3881     le_def_join             ~> le_iff_sup
  3882     join_absorp2            ~> sup_absorb2
  3883     join_absorp1            ~> sup_absorb1
  3884     meet_absorp1            ~> inf_absorb1
  3885     meet_absorp2            ~> inf_absorb2
  3886     meet_join_absorp        ~> inf_sup_absorb
  3887     join_meet_absorp        ~> sup_inf_absorb
  3888     distrib_join_le         ~> distrib_sup_le
  3889     distrib_meet_le         ~> distrib_inf_le
  3890 
  3891     add_meet_distrib_left   ~> add_inf_distrib_left
  3892     add_join_distrib_left   ~> add_sup_distrib_left
  3893     is_join_neg_meet        ~> is_join_neg_inf
  3894     is_meet_neg_join        ~> is_meet_neg_sup
  3895     add_meet_distrib_right  ~> add_inf_distrib_right
  3896     add_join_distrib_right  ~> add_sup_distrib_right
  3897     add_meet_join_distribs  ~> add_sup_inf_distribs
  3898     join_eq_neg_meet        ~> sup_eq_neg_inf
  3899     meet_eq_neg_join        ~> inf_eq_neg_sup
  3900     add_eq_meet_join        ~> add_eq_inf_sup
  3901     meet_0_imp_0            ~> inf_0_imp_0
  3902     join_0_imp_0            ~> sup_0_imp_0
  3903     meet_0_eq_0             ~> inf_0_eq_0
  3904     join_0_eq_0             ~> sup_0_eq_0
  3905     neg_meet_eq_join        ~> neg_inf_eq_sup
  3906     neg_join_eq_meet        ~> neg_sup_eq_inf
  3907     join_eq_if              ~> sup_eq_if
  3908 
  3909     mono_meet               ~> mono_inf
  3910     mono_join               ~> mono_sup
  3911     meet_bool_eq            ~> inf_bool_eq
  3912     join_bool_eq            ~> sup_bool_eq
  3913     meet_fun_eq             ~> inf_fun_eq
  3914     join_fun_eq             ~> sup_fun_eq
  3915     meet_set_eq             ~> inf_set_eq
  3916     join_set_eq             ~> sup_set_eq
  3917     meet1_iff               ~> inf1_iff
  3918     meet2_iff               ~> inf2_iff
  3919     meet1I                  ~> inf1I
  3920     meet2I                  ~> inf2I
  3921     meet1D1                 ~> inf1D1
  3922     meet2D1                 ~> inf2D1
  3923     meet1D2                 ~> inf1D2
  3924     meet2D2                 ~> inf2D2
  3925     meet1E                  ~> inf1E
  3926     meet2E                  ~> inf2E
  3927     join1_iff               ~> sup1_iff
  3928     join2_iff               ~> sup2_iff
  3929     join1I1                 ~> sup1I1
  3930     join2I1                 ~> sup2I1
  3931     join1I1                 ~> sup1I1
  3932     join2I2                 ~> sup1I2
  3933     join1CI                 ~> sup1CI
  3934     join2CI                 ~> sup2CI
  3935     join1E                  ~> sup1E
  3936     join2E                  ~> sup2E
  3937 
  3938     is_meet_Meet            ~> is_meet_Inf
  3939     Meet_bool_def           ~> Inf_bool_def
  3940     Meet_fun_def            ~> Inf_fun_def
  3941     Meet_greatest           ~> Inf_greatest
  3942     Meet_lower              ~> Inf_lower
  3943     Meet_set_def            ~> Inf_set_def
  3944 
  3945     Sup_def                 ~> Sup_Inf
  3946     Sup_bool_eq             ~> Sup_bool_def
  3947     Sup_fun_eq              ~> Sup_fun_def
  3948     Sup_set_eq              ~> Sup_set_def
  3949 
  3950     listsp_meetI            ~> listsp_infI
  3951     listsp_meet_eq          ~> listsp_inf_eq
  3952 
  3953     meet_min                ~> inf_min
  3954     join_max                ~> sup_max
  3955 
  3956 * Added syntactic class "size"; overloaded constant "size" now has
  3957 type "'a::size ==> bool"
  3958 
  3959 * Internal reorganisation of `size' of datatypes: size theorems
  3960 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3961 simplification rules by default!); theorems "prod.size" now named
  3962 "*.size".
  3963 
  3964 * Class "div" now inherits from class "times" rather than "type".
  3965 INCOMPATIBILITY.
  3966 
  3967 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  3968 Linorder etc.  have disappeared; operations defined in terms of
  3969 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  3970 
  3971 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  3972 
  3973 * HOL-Word: New extensive library and type for generic, fixed size
  3974 machine words, with arithemtic, bit-wise, shifting and rotating
  3975 operations, reflection into int, nat, and bool lists, automation for
  3976 linear arithmetic (by automatic reflection into nat or int), including
  3977 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  3978 arithmetic type classes, supporting automatic simplification of
  3979 numerals on all operations.
  3980 
  3981 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  3982 
  3983 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  3984 
  3985 * Code generator library theories:
  3986   - Code_Integer represents HOL integers by big integer literals in target
  3987     languages.
  3988   - Code_Char represents HOL characters by character literals in target
  3989     languages.
  3990   - Code_Char_chr like Code_Char, but also offers treatment of character
  3991     codes; includes Code_Integer.
  3992   - Executable_Set allows to generate code for finite sets using lists.
  3993   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  3994     denominator).
  3995   - Executable_Real implements a subset of real numbers, namly those
  3996     representable by rational numbers.
  3997   - Efficient_Nat implements natural numbers by integers, which in general will
  3998     result in higher efficency; pattern matching with 0/Suc is eliminated;
  3999     includes Code_Integer.
  4000   - Code_Index provides an additional datatype index which is mapped to
  4001     target-language built-in integers.
  4002   - Code_Message provides an additional datatype message_string which is isomorphic to
  4003     strings; messages are mapped to target-language strings.
  4004 
  4005 * New package for inductive predicates
  4006 
  4007   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  4008 
  4009     inductive
  4010       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4011       for z_1 :: U_1 and ... and z_n :: U_m
  4012     where
  4013       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4014     | ...
  4015 
  4016   with full support for type-inference, rather than
  4017 
  4018     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4019 
  4020     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4021     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4022 
  4023     inductive "s z_1 ... z_m"
  4024     intros
  4025       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4026       ...
  4027 
  4028   For backward compatibility, there is a wrapper allowing inductive
  4029   sets to be defined with the new package via
  4030 
  4031     inductive_set
  4032       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4033       for z_1 :: U_1 and ... and z_n :: U_m
  4034     where
  4035       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4036     | ...
  4037 
  4038   or
  4039 
  4040     inductive_set
  4041       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4042       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4043       for z_1 :: U_1 and ... and z_n :: U_m
  4044     where
  4045       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4046     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4047     | ...
  4048 
  4049   if the additional syntax "p ..." is required.
  4050 
  4051   Numerous examples can be found in the subdirectories src/HOL/Auth,
  4052   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  4053 
  4054   INCOMPATIBILITIES:
  4055 
  4056   - Since declaration and definition of inductive sets or predicates
  4057     is no longer separated, abbreviations involving the newly
  4058     introduced sets or predicates must be specified together with the
  4059     introduction rules after the 'where' keyword (see above), rather
  4060     than before the actual inductive definition.
  4061 
  4062   - The variables in induction and elimination rules are now
  4063     quantified in the order of their occurrence in the introduction
  4064     rules, rather than in alphabetical order. Since this may break
  4065     some proofs, these proofs either have to be repaired, e.g. by
  4066     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  4067     statements of the form
  4068 
  4069       case (rule_i a_i_1 ... a_i_{k_i})
  4070 
  4071     or the old order of quantification has to be restored by explicitly adding
  4072     meta-level quantifiers in the introduction rules, i.e.
  4073 
  4074       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  4075 
  4076   - The format of the elimination rules is now
  4077 
  4078       p z_1 ... z_m x_1 ... x_n ==>
  4079         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4080         ==> ... ==> P
  4081 
  4082     for predicates and
  4083 
  4084       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4085         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4086         ==> ... ==> P
  4087 
  4088     for sets rather than
  4089 
  4090       x : s z_1 ... z_m ==>
  4091         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4092         ==> ... ==> P
  4093 
  4094     This may require terms in goals to be expanded to n-tuples
  4095     (e.g. using case_tac or simplification with the split_paired_all
  4096     rule) before the above elimination rule is applicable.
  4097 
  4098   - The elimination or case analysis rules for (mutually) inductive
  4099     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4100     list of rules "p_1_..._p_k.elims" is no longer available.
  4101 
  4102 * New package "function"/"fun" for general recursive functions,
  4103 supporting mutual and nested recursion, definitions in local contexts,
  4104 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4105 for small examples, and the separate tutorial on the function
  4106 package. The old recdef "package" is still available as before, but
  4107 users are encouraged to use the new package.
  4108 
  4109 * Method "lexicographic_order" automatically synthesizes termination
  4110 relations as lexicographic combinations of size measures. 
  4111 
  4112 * Case-expressions allow arbitrary constructor-patterns (including
  4113 "_") and take their order into account, like in functional
  4114 programming.  Internally, this is translated into nested
  4115 case-expressions; missing cases are added and mapped to the predefined
  4116 constant "undefined". In complicated cases printing may no longer show
  4117 the original input but the internal form. Lambda-abstractions allow
  4118 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4119 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4120 variable.
  4121 
  4122 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4123 is an abbreviation for "of_nat :: nat => int". The simplification
  4124 rules for "of_nat" have been changed to work like "int" did
  4125 previously.  Potential INCOMPATIBILITY:
  4126   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4127   - of_nat_diff and of_nat_mult are no longer default simp rules
  4128 
  4129 * Method "algebra" solves polynomial equations over (semi)rings using
  4130 Groebner bases. The (semi)ring structure is defined by locales and the
  4131 tool setup depends on that generic context. Installing the method for
  4132 a specific type involves instantiating the locale and possibly adding
  4133 declarations for computation on the coefficients.  The method is
  4134 already instantiated for natural numbers and for the axiomatic class
  4135 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4136 CALCULEMUS 2007 for the general principles underlying this
  4137 architecture of context-aware proof-tools.
  4138 
  4139 * Method "ferrack" implements quantifier elimination over
  4140 special-purpose dense linear orders using locales (analogous to
  4141 "algebra"). The method is already installed for class
  4142 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4143 rat, etc.
  4144 
  4145 * Former constant "List.op @" now named "List.append".  Use ML
  4146 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4147 circumvent possible incompatibilities when working on ML level.
  4148 
  4149 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4150 
  4151 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4152 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4153 
  4154 * New syntax for Haskell-like list comprehension (input only), eg.
  4155 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4156 
  4157 * The special syntax for function "filter" has changed from [x :
  4158 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4159 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4160 
  4161 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4162 defined on nat only, as an abbreviation for [a..<Suc b]
  4163 INCOMPATIBILITY.
  4164 
  4165 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4166 
  4167 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4168 
  4169 * New lemma collection field_simps (an extension of ring_simps) for
  4170 manipulating (in)equations involving division. Multiplies with all
  4171 denominators that can be proved to be non-zero (in equations) or
  4172 positive/negative (in inequations).
  4173 
  4174 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4175 have been improved and renamed to ring_simps, group_simps and
  4176 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4177 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4178 
  4179 * Theory Library/Commutative_Ring: switched from recdef to function
  4180 package; constants add, mul, pow now curried.  Infix syntax for
  4181 algebraic operations.
  4182 
  4183 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4184 INCOMPATIBILITY.
  4185 
  4186 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4187 INCOMPATIBILITY.
  4188 
  4189 * HOL/records: generalised field-update to take a function on the
  4190 field rather than the new value: r(|A := x|) is translated to A_update
  4191 (K x) r The K-combinator that is internally used is called K_record.
  4192 INCOMPATIBILITY: Usage of the plain update functions has to be
  4193 adapted.
  4194  
  4195 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4196 * x = 0, which are required for a semiring.  Richer structures do not
  4197 inherit from semiring_0 anymore, because this property is a theorem
  4198 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4199 there is more to prove, but this is mostly trivial.
  4200 
  4201 * Class "recpower" is generalized to arbitrary monoids, not just
  4202 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4203 commutativity or semiring properties additionally.
  4204 
  4205 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4206 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4207 better use 'abbreviation'.
  4208 
  4209 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4210 
  4211 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4212 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4213 significant changes for setting up numeral syntax for types:
  4214   - New constants Numeral.pred and Numeral.succ instead
  4215       of former Numeral.bin_pred and Numeral.bin_succ.
  4216   - Use integer operations instead of bin_add, bin_mult and so on.
  4217   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4218   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4219 
  4220 See src/HOL/Integ/IntArith.thy for an example setup.
  4221 
  4222 * Command 'normal_form' computes the normal form of a term that may
  4223 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4224 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4225 heavy-duty computations because the functions are compiled to ML
  4226 first.  Correspondingly, a method "normalization" is provided.  See
  4227 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4228 
  4229 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4230 25 like -->); output depends on the "iff" print_mode, the default is
  4231 "A = B" (with priority 50).
  4232 
  4233 * Relations less (<) and less_eq (<=) are also available on type bool.
  4234 Modified syntax to disallow nesting without explicit parentheses,
  4235 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4236 INCOMPATIBILITY.
  4237 
  4238 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4239 
  4240 * Relation composition operator "op O" now has precedence 75 and binds
  4241 stronger than union and intersection. INCOMPATIBILITY.
  4242 
  4243 * The old set interval syntax "{m..n(}" (and relatives) has been
  4244 removed.  Use "{m..<n}" (and relatives) instead.
  4245 
  4246 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4247 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4248 ``declare [[simproc del: neq]]''.
  4249 
  4250 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4251 True/False.
  4252 
  4253 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4254 
  4255 * Theorem setsum_mult renamed to setsum_right_distrib.
  4256 
  4257 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4258 ``rule'' method.
  4259 
  4260 * Reimplemented methods "sat" and "satx", with several improvements:
  4261 goals no longer need to be stated as "<prems> ==> False", equivalences
  4262 (i.e. "=" on type bool) are handled, variable names of the form
  4263 "lit_<n>" are no longer reserved, significant speedup.
  4264 
  4265 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4266 zChaff is still supported as well.
  4267 
  4268 * 'inductive' and 'datatype': provide projections of mutual rules,
  4269 bundled as foo_bar.inducts;
  4270 
  4271 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4272 Library.
  4273 
  4274 * Library: moved theory Accessible_Part to main HOL.
  4275 
  4276 * Library: added theory Coinductive_List of potentially infinite lists
  4277 as greatest fixed-point.
  4278 
  4279 * Library: added theory AssocList which implements (finite) maps as
  4280 association lists.
  4281 
  4282 * Method "evaluation" solves goals (i.e. a boolean expression)
  4283 efficiently by compiling it to ML.  The goal is "proved" (via an
  4284 oracle) if it evaluates to True.
  4285 
  4286 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4287 also when invoked by the simplifier.  This results in the Simplifier
  4288 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4289 Configuration option fast_arith_split_limit=0 recovers the old
  4290 behavior.
  4291 
  4292 * Support for hex (0x20) and binary (0b1001) numerals.
  4293 
  4294 * New method: reify eqs (t), where eqs are equations for an
  4295 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4296 parameter, computes a term s::'b and a list xs::'a list and proves the
  4297 theorem I xs s = t. This is also known as reification or quoting. The
  4298 resulting theorem is applied to the subgoal to substitute t with I xs
  4299 s.  If t is omitted, the subgoal itself is reified.
  4300 
  4301 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4302 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4303 where f is supposed to be a computable function (in the sense of code
  4304 generattion). The method uses reify to compute s and xs as above then
  4305 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4306 r and finally gets the theorem t = r, which is again applied to the
  4307 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4308 
  4309 * Reflection: Automatic reification now handels binding, an example is
  4310 available in src/HOL/ex/ReflectionEx.thy
  4311 
  4312 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4313 command 'statespace' that is similar to 'record', but introduces an
  4314 abstract specification based on the locale infrastructure instead of
  4315 HOL types.  This leads to extra flexibility in composing state spaces,
  4316 in particular multiple inheritance and renaming of components.
  4317 
  4318 
  4319 *** HOL-Complex ***
  4320 
  4321 * Hyperreal: Functions root and sqrt are now defined on negative real
  4322 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4323 Nonnegativity side conditions have been removed from many lemmas, so
  4324 that more subgoals may now be solved by simplification; potential
  4325 INCOMPATIBILITY.
  4326 
  4327 * Real: new type classes formalize real normed vector spaces and
  4328 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4329 and norm :: 'a => real.
  4330 
  4331 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4332 reals into other types. The overloaded constant Reals :: 'a set is now
  4333 defined as range of_real; potential INCOMPATIBILITY.
  4334 
  4335 * Real: proper support for ML code generation, including 'quickcheck'.
  4336 Reals are implemented as arbitrary precision rationals.
  4337 
  4338 * Hyperreal: Several constants that previously worked only for the
  4339 reals have been generalized, so they now work over arbitrary vector
  4340 spaces. Type annotations may need to be added in some cases; potential
  4341 INCOMPATIBILITY.
  4342 
  4343   Infinitesimal  :: ('a::real_normed_vector) star set
  4344   HFinite        :: ('a::real_normed_vector) star set
  4345   HInfinite      :: ('a::real_normed_vector) star set
  4346   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4347   monad          :: ('a::real_normed_vector) star => 'a star set
  4348   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4349   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4350   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4351   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4352   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4353   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4354   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4355   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4356   sgn            :: 'a::real_normed_vector => 'a
  4357   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4358 
  4359 * Complex: Some complex-specific constants are now abbreviations for
  4360 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4361 hnorm.  Other constants have been entirely removed in favor of the
  4362 polymorphic versions (INCOMPATIBILITY):
  4363 
  4364   approx        <-- capprox
  4365   HFinite       <-- CFinite
  4366   HInfinite     <-- CInfinite
  4367   Infinitesimal <-- CInfinitesimal
  4368   monad         <-- cmonad
  4369   galaxy        <-- cgalaxy
  4370   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4371   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4372   (ns)deriv     <-- (ns)cderiv
  4373 
  4374 
  4375 *** HOL-Algebra ***
  4376 
  4377 * Formalisation of ideals and the quotient construction over rings.
  4378 
  4379 * Order and lattice theory no longer based on records.
  4380 INCOMPATIBILITY.
  4381 
  4382 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4383 greatest_closed.  INCOMPATIBILITY.
  4384 
  4385 * Method algebra is now set up via an attribute.  For examples see
  4386 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4387 of algebraic structures.
  4388 
  4389 * Renamed theory CRing to Ring.
  4390 
  4391 
  4392 *** HOL-Nominal ***
  4393 
  4394 * Substantial, yet incomplete support for nominal datatypes (binding
  4395 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4396 src/HOL/Nominal/Examples.  Prospective users should consult
  4397 http://isabelle.in.tum.de/nominal/
  4398 
  4399 
  4400 *** ML ***
  4401 
  4402 * ML basics: just one true type int, which coincides with IntInf.int
  4403 (even on SML/NJ).
  4404 
  4405 * ML within Isar: antiquotations allow to embed statically-checked
  4406 formal entities in the source, referring to the context available at
  4407 compile-time.  For example:
  4408 
  4409 ML {* @{sort "{zero,one}"} *}
  4410 ML {* @{typ "'a => 'b"} *}
  4411 ML {* @{term "%x. x"} *}
  4412 ML {* @{prop "x == y"} *}
  4413 ML {* @{ctyp "'a => 'b"} *}
  4414 ML {* @{cterm "%x. x"} *}
  4415 ML {* @{cprop "x == y"} *}
  4416 ML {* @{thm asm_rl} *}
  4417 ML {* @{thms asm_rl} *}
  4418 ML {* @{type_name c} *}
  4419 ML {* @{type_syntax c} *}
  4420 ML {* @{const_name c} *}
  4421 ML {* @{const_syntax c} *}
  4422 ML {* @{context} *}
  4423 ML {* @{theory} *}
  4424 ML {* @{theory Pure} *}
  4425 ML {* @{theory_ref} *}
  4426 ML {* @{theory_ref Pure} *}
  4427 ML {* @{simpset} *}
  4428 ML {* @{claset} *}
  4429 ML {* @{clasimpset} *}
  4430 
  4431 The same works for sources being ``used'' within an Isar context.
  4432 
  4433 * ML in Isar: improved error reporting; extra verbosity with
  4434 ML_Context.trace enabled.
  4435 
  4436 * Pure/General/table.ML: the join operations now works via exceptions
  4437 DUP/SAME instead of type option. This is simpler in simple cases, and
  4438 admits slightly more efficient complex applications.
  4439 
  4440 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4441 use Context.generic instead of just theory.
  4442 
  4443 * Pure: datatype Context.generic joins theory/Proof.context and
  4444 provides some facilities for code that works in either kind of
  4445 context, notably GenericDataFun for uniform theory and proof data.
  4446 
  4447 * Pure: simplified internal attribute type, which is now always
  4448 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4449 local (Proof.context) attributes have been discontinued, while
  4450 minimizing code duplication. Thm.rule_attribute and
  4451 Thm.declaration_attribute build canonical attributes; see also structure
  4452 Context for further operations on Context.generic, notably
  4453 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4454 declarations and definitions.
  4455 
  4456 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4457 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4458 init only required for impure data. INCOMPATIBILITY: empty really need
  4459 to be empty (no dependencies on theory content!)
  4460 
  4461 * Pure/kernel: consts certification ignores sort constraints given in
  4462 signature declarations. (This information is not relevant to the
  4463 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4464 potential INCOMPATIBILITY.
  4465 
  4466 * Pure: axiomatic type classes are now purely definitional, with
  4467 explicit proofs of class axioms and super class relations performed
  4468 internally. See Pure/axclass.ML for the main internal interfaces --
  4469 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4470 AxClass.axiomatize_class/classrel/arity supersede
  4471 Sign.add_classes/classrel/arities.
  4472 
  4473 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4474 global/local versions on theory vs. Proof.context have been
  4475 discontinued; Attrib.syntax and Method.syntax have been adapted
  4476 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4477 attributes, methods, etc.
  4478 
  4479 * Pure: several functions of signature "... -> theory -> theory * ..."
  4480 have been reoriented to "... -> theory -> ... * theory" in order to
  4481 allow natural usage in combination with the ||>, ||>>, |-> and
  4482 fold_map combinators.
  4483 
  4484 * Pure: official theorem names (closed derivations) and additional
  4485 comments (tags) are now strictly separate.  Name hints -- which are
  4486 maintained as tags -- may be attached any time without affecting the
  4487 derivation.
  4488 
  4489 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4490 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4491 achieve the old behaviour.
  4492 
  4493 * Pure: the "Goal" constant is now called "prop", supporting a
  4494 slightly more general idea of ``protecting'' meta-level rule
  4495 statements.
  4496 
  4497 * Pure: Logic.(un)varify only works in a global context, which is now
  4498 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4499 Logic.legacy_(un)varify as temporary workaround.
  4500 
  4501 * Pure: structure Name provides scalable operations for generating
  4502 internal variable names, notably Name.variants etc.  This replaces
  4503 some popular functions from term.ML:
  4504 
  4505   Term.variant		->  Name.variant
  4506   Term.variantlist	->  Name.variant_list
  4507   Term.invent_names	->  Name.invent_list
  4508 
  4509 Note that low-level renaming rarely occurs in new code -- operations
  4510 from structure Variable are used instead (see below).
  4511 
  4512 * Pure: structure Variable provides fundamental operations for proper
  4513 treatment of fixed/schematic variables in a context.  For example,
  4514 Variable.import introduces fixes for schematics of given facts and
  4515 Variable.export reverses the effect (up to renaming) -- this replaces
  4516 various freeze_thaw operations.
  4517 
  4518 * Pure: structure Goal provides simple interfaces for
  4519 init/conclude/finish and tactical prove operations (replacing former
  4520 Tactic.prove).  Goal.prove is the canonical way to prove results
  4521 within a given context; Goal.prove_global is a degraded version for
  4522 theory level goals, including a global Drule.standard.  Note that
  4523 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4524 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4525 in a locale context).
  4526 
  4527 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4528 and type checking (Syntax.check_term etc.), with common combinations
  4529 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4530 which are considered legacy and await removal.
  4531 
  4532 * Pure/Syntax: generic interfaces for type unchecking
  4533 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4534 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4535 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4536 available for convenience, but refer to the very same operations using
  4537 a mere theory instead of a full context.
  4538 
  4539 * Isar: simplified treatment of user-level errors, using exception
  4540 ERROR of string uniformly.  Function error now merely raises ERROR,
  4541 without any side effect on output channels.  The Isar toplevel takes
  4542 care of proper display of ERROR exceptions.  ML code may use plain
  4543 handle/can/try; cat_error may be used to concatenate errors like this:
  4544 
  4545   ... handle ERROR msg => cat_error msg "..."
  4546 
  4547 Toplevel ML code (run directly or through the Isar toplevel) may be
  4548 embedded into the Isar toplevel with exception display/debug like
  4549 this:
  4550 
  4551   Isar.toplevel (fn () => ...)
  4552 
  4553 INCOMPATIBILITY, removed special transform_error facilities, removed
  4554 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4555 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4556 -- use plain ERROR instead.
  4557 
  4558 * Isar: theory setup now has type (theory -> theory), instead of a
  4559 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4560 
  4561 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4562 ProofContext.debug/verbose flags.
  4563 
  4564 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4565 theory before entering a proof state.  Transactions now always see a
  4566 quasi-functional intermediate checkpoint, both in interactive and
  4567 batch mode.
  4568 
  4569 * Isar: simplified interfaces for outer syntax.  Renamed
  4570 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4571 OuterSyntax.add_parsers -- this functionality is now included in
  4572 OuterSyntax.command etc.  INCOMPATIBILITY.
  4573 
  4574 * Simplifier: the simpset of a running simplification process now
  4575 contains a proof context (cf. Simplifier.the_context), which is the
  4576 very context that the initial simpset has been retrieved from (by
  4577 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4578 (solver, looper etc.) may depend on arbitrary proof data.
  4579 
  4580 * Simplifier.inherit_context inherits the proof context (plus the
  4581 local bounds) of the current simplification process; any simproc
  4582 etc. that calls the Simplifier recursively should do this!  Removed
  4583 former Simplifier.inherit_bounds, which is already included here --
  4584 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4585 specify an explicit context using Simplifier.context/theory_context.
  4586 
  4587 * Simplifier/Classical Reasoner: more abstract interfaces
  4588 change_simpset/claset for modifying the simpset/claset reference of a
  4589 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4590 INCOMPATIBILITY.
  4591 
  4592 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4593 "Trueprop" etc.
  4594 
  4595 
  4596 *** System ***
  4597 
  4598 * settings: the default heap location within ISABELLE_HOME_USER now
  4599 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4600 Isabelle installations.
  4601 
  4602 * isabelle-process: option -S (secure mode) disables some critical
  4603 operations, notably runtime compilation and evaluation of ML source
  4604 code.
  4605 
  4606 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4607 
  4608 * Support for parallel execution, using native multicore support of
  4609 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4610 independent theories, according to the given theory header
  4611 specifications. The maximum number of worker threads is specified via
  4612 usedir option -M or the "max-threads" setting in Proof General. A
  4613 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4614 to 6 on a 8-core machine.  User-code needs to observe certain
  4615 guidelines for thread-safe programming, see appendix A in the Isar
  4616 Implementation manual.
  4617 
  4618 
  4619 
  4620 New in Isabelle2005 (October 2005)
  4621 ----------------------------------
  4622 
  4623 *** General ***
  4624 
  4625 * Theory headers: the new header syntax for Isar theories is
  4626 
  4627   theory <name>
  4628   imports <theory1> ... <theoryN>
  4629   uses <file1> ... <fileM>
  4630   begin
  4631 
  4632 where the 'uses' part is optional.  The previous syntax
  4633 
  4634   theory <name> = <theory1> + ... + <theoryN>:
  4635 
  4636 will disappear in the next release.  Use isatool fixheaders to convert
  4637 existing theory files.  Note that there is no change in ancient
  4638 non-Isar theories now, but these will disappear soon.
  4639 
  4640 * Theory loader: parent theories can now also be referred to via
  4641 relative and absolute paths.
  4642 
  4643 * Command 'find_theorems' searches for a list of criteria instead of a
  4644 list of constants. Known criteria are: intro, elim, dest, name:string,
  4645 simp:term, and any term. Criteria can be preceded by '-' to select
  4646 theorems that do not match. Intro, elim, dest select theorems that
  4647 match the current goal, name:s selects theorems whose fully qualified
  4648 name contain s, and simp:term selects all simplification rules whose
  4649 lhs match term.  Any other term is interpreted as pattern and selects
  4650 all theorems matching the pattern. Available in ProofGeneral under
  4651 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4652 
  4653   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4654 
  4655 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4656 matching the current goal as introduction rule and not having "HOL."
  4657 in their name (i.e. not being defined in theory HOL).
  4658 
  4659 * Command 'thms_containing' has been discontinued in favour of
  4660 'find_theorems'; INCOMPATIBILITY.
  4661 
  4662 * Communication with Proof General is now 8bit clean, which means that
  4663 Unicode text in UTF-8 encoding may be used within theory texts (both
  4664 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4665 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4666 
  4667   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4668   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4669 
  4670 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4671 Classical Reasoner.  Typical big applications run around 2 times
  4672 faster.
  4673 
  4674 
  4675 *** Document preparation ***
  4676 
  4677 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4678 of raw sources.  Only those symbols that do not require additional
  4679 LaTeX packages (depending on comments in isabellesym.sty) are
  4680 displayed properly, everything else is left verbatim.  isatool display
  4681 and isatool print are used as front ends (these are subject to the
  4682 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4683 
  4684 * Command tags control specific markup of certain regions of text,
  4685 notably folding and hiding.  Predefined tags include "theory" (for
  4686 theory begin and end), "proof" for proof commands, and "ML" for
  4687 commands involving ML code; the additional tags "visible" and
  4688 "invisible" are unused by default.  Users may give explicit tag
  4689 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4690 interpretation of tags is determined by the LaTeX job during document
  4691 preparation: see option -V of isatool usedir, or options -n and -t of
  4692 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4693 \isadroptag.
  4694 
  4695 Several document versions may be produced at the same time via isatool
  4696 usedir (the generated index.html will link all of them).  Typical
  4697 specifications include ''-V document=theory,proof,ML'' to present
  4698 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4699 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4700 these parts without any formal replacement text.  The Isabelle site
  4701 default settings produce ''document'' and ''outline'' versions as
  4702 specified above.
  4703 
  4704 * Several new antiquotations:
  4705 
  4706   @{term_type term} prints a term with its type annotated;
  4707 
  4708   @{typeof term} prints the type of a term;
  4709 
  4710   @{const const} is the same as @{term const}, but checks that the
  4711   argument is a known logical constant;
  4712 
  4713   @{term_style style term} and @{thm_style style thm} print a term or
  4714   theorem applying a "style" to it
  4715 
  4716   @{ML text}
  4717 
  4718 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4719 definitions, equations, inequations etc., 'concl' printing only the
  4720 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4721 to print the specified premise.  TermStyle.add_style provides an ML
  4722 interface for introducing further styles.  See also the "LaTeX Sugar"
  4723 document practical applications.  The ML antiquotation prints
  4724 type-checked ML expressions verbatim.
  4725 
  4726 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4727 and 'text' support optional locale specification '(in loc)', which
  4728 specifies the default context for interpreting antiquotations.  For
  4729 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4730 
  4731 * Option 'locale=NAME' of antiquotations specifies an alternative
  4732 context interpreting the subsequent argument.  For example: @{thm
  4733 [locale=lattice] inf_assoc}.
  4734 
  4735 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4736 a proof context.
  4737 
  4738 * Proper output of antiquotations for theory commands involving a
  4739 proof context (such as 'locale' or 'theorem (in loc) ...').
  4740 
  4741 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4742 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4743 
  4744 * isatool usedir: new option -C (default true) controls whether option
  4745 -D should include a copy of the original document directory; -C false
  4746 prevents unwanted effects such as copying of administrative CVS data.
  4747 
  4748 
  4749 *** Pure ***
  4750 
  4751 * Considerably improved version of 'constdefs' command.  Now performs
  4752 automatic type-inference of declared constants; additional support for
  4753 local structure declarations (cf. locales and HOL records), see also
  4754 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4755 sequential dependencies of definitions within a single 'constdefs'
  4756 section; moreover, the declared name needs to be an identifier.  If
  4757 all fails, consider to fall back on 'consts' and 'defs' separately.
  4758 
  4759 * Improved indexed syntax and implicit structures.  First of all,
  4760 indexed syntax provides a notational device for subscripted
  4761 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4762 expressions.  Secondly, in a local context with structure
  4763 declarations, number indexes \<^sub>n or the empty index (default
  4764 number 1) refer to a certain fixed variable implicitly; option
  4765 show_structs controls printing of implicit structures.  Typical
  4766 applications of these concepts involve record types and locales.
  4767 
  4768 * New command 'no_syntax' removes grammar declarations (and
  4769 translations) resulting from the given syntax specification, which is
  4770 interpreted in the same manner as for the 'syntax' command.
  4771 
  4772 * 'Advanced' translation functions (parse_translation etc.) may depend
  4773 on the signature of the theory context being presently used for
  4774 parsing/printing, see also isar-ref manual.
  4775 
  4776 * Improved 'oracle' command provides a type-safe interface to turn an
  4777 ML expression of type theory -> T -> term into a primitive rule of
  4778 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4779 is already included here); see also FOL/ex/IffExample.thy;
  4780 INCOMPATIBILITY.
  4781 
  4782 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4783 before); "cI" is no longer bound, use "c.intro" instead.
  4784 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4785 axclasses vs. locales.
  4786 
  4787 * Improved internal renaming of symbolic identifiers -- attach primes
  4788 instead of base 26 numbers.
  4789 
  4790 * New flag show_question_marks controls printing of leading question
  4791 marks in schematic variable names.
  4792 
  4793 * In schematic variable names, *any* symbol following \<^isub> or
  4794 \<^isup> is now treated as part of the base name.  For example, the
  4795 following works without printing of awkward ".0" indexes:
  4796 
  4797   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4798     by simp
  4799 
  4800 * Inner syntax includes (*(*nested*) comments*).
  4801 
  4802 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4803 annotations as "(00...)".
  4804 
  4805 * Clear separation of logical types and nonterminals, where the latter
  4806 may only occur in 'syntax' specifications or type abbreviations.
  4807 Before that distinction was only partially implemented via type class
  4808 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4809 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4810 exotic syntax specifications may require further adaption
  4811 (e.g. Cube/Cube.thy).
  4812 
  4813 * Removed obsolete type class "logic", use the top sort {} instead.
  4814 Note that non-logical types should be declared as 'nonterminals'
  4815 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4816 specifications.
  4817 
  4818 * Attributes 'induct' and 'cases': type or set names may now be
  4819 locally fixed variables as well.
  4820 
  4821 * Simplifier: can now control the depth to which conditional rewriting
  4822 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4823 Limit.
  4824 
  4825 * Simplifier: simplification procedures may now take the current
  4826 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4827 interface), which is very useful for calling the Simplifier
  4828 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4829 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4830 low-level mk_simproc no longer applies Logic.varify internally, to
  4831 allow for use in a context of fixed variables.
  4832 
  4833 * thin_tac now works even if the assumption being deleted contains !!
  4834 or ==>.  More generally, erule now works even if the major premise of
  4835 the elimination rule contains !! or ==>.
  4836 
  4837 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4838 
  4839 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4840 from Pure, which contains all common declarations already.  Both
  4841 theories are defined via plain Isabelle/Isar .thy files.
  4842 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4843 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4844 use isatool fixcpure to adapt your theory and ML sources.
  4845 
  4846 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4847 selections of theorems in named facts via index ranges.
  4848 
  4849 * 'print_theorems': in theory mode, really print the difference
  4850 wrt. the last state (works for interactive theory development only),
  4851 in proof mode print all local facts (cf. 'print_facts');
  4852 
  4853 * 'hide': option '(open)' hides only base names.
  4854 
  4855 * More efficient treatment of intermediate checkpoints in interactive
  4856 theory development.
  4857 
  4858 * Code generator is now invoked via code_module (incremental code
  4859 generation) and code_library (modular code generation, ML structures
  4860 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4861 must be quoted when used as identifiers.
  4862 
  4863 * New 'value' command for reading, evaluating and printing terms using
  4864 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4865 quoted when used as identifier.
  4866 
  4867 
  4868 *** Locales ***
  4869 
  4870 * New commands for the interpretation of locale expressions in
  4871 theories (1), locales (2) and proof contexts (3).  These generate
  4872 proof obligations from the expression specification.  After the
  4873 obligations have been discharged, theorems of the expression are added
  4874 to the theory, target locale or proof context.  The synopsis of the
  4875 commands is a follows:
  4876 
  4877   (1) interpretation expr inst
  4878   (2) interpretation target < expr
  4879   (3) interpret expr inst
  4880 
  4881 Interpretation in theories and proof contexts require a parameter
  4882 instantiation of terms from the current context.  This is applied to
  4883 specifications and theorems of the interpreted expression.
  4884 Interpretation in locales only permits parameter renaming through the
  4885 locale expression.  Interpretation is smart in that interpretations
  4886 that are active already do not occur in proof obligations, neither are
  4887 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4888 inspect active interpretations of a particular locale.  For details,
  4889 see the Isar Reference manual.  Examples can be found in
  4890 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4891 
  4892 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4893 'interpret' instead.
  4894 
  4895 * New context element 'constrains' for adding type constraints to
  4896 parameters.
  4897 
  4898 * Context expressions: renaming of parameters with syntax
  4899 redeclaration.
  4900 
  4901 * Locale declaration: 'includes' disallowed.
  4902 
  4903 * Proper static binding of attribute syntax -- i.e. types / terms /
  4904 facts mentioned as arguments are always those of the locale definition
  4905 context, independently of the context of later invocations.  Moreover,
  4906 locale operations (renaming and type / term instantiation) are applied
  4907 to attribute arguments as expected.
  4908 
  4909 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4910 actual attributes; rare situations may require Attrib.attribute to
  4911 embed those attributes into Attrib.src that lack concrete syntax.
  4912 Attribute implementations need to cooperate properly with the static
  4913 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4914 Attrib.XXX_thm etc. already do the right thing without further
  4915 intervention.  Only unusual applications -- such as "where" or "of"
  4916 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4917 on the context and the facts involved -- may have to assign parsed
  4918 values to argument tokens explicitly.
  4919 
  4920 * Changed parameter management in theorem generation for long goal
  4921 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4922 theorem statement in rare situations.
  4923 
  4924 * Locale inspection command 'print_locale' omits notes elements.  Use
  4925 'print_locale!' to have them included in the output.
  4926 
  4927 
  4928 *** Provers ***
  4929 
  4930 * Provers/hypsubst.ML: improved version of the subst method, for
  4931 single-step rewriting: it now works in bound variable contexts. New is
  4932 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4933 rewrite a different subterm than the original subst method, which is
  4934 still available as 'simplesubst'.
  4935 
  4936 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4937 and quasi orders.
  4938 
  4939 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4940 reflexive-transitive closure of relations.
  4941 
  4942 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4943 limit (previously hard-coded with a value of 20) user-definable.
  4944 
  4945 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4946 is peformed already.  Object-logics merely need to finish their
  4947 initial simpset configuration as before.  INCOMPATIBILITY.
  4948 
  4949 
  4950 *** HOL ***
  4951 
  4952 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4953 
  4954   syntax (epsilon)
  4955     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4956 
  4957 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4958 and x-symbol; use option '-m epsilon' to get it actually printed.
  4959 Moreover, the mathematically important symbolic identifier \<epsilon>
  4960 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4961 
  4962 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  4963 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  4964 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  4965 support corresponding Isar calculations.
  4966 
  4967 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  4968 instead of ":".
  4969 
  4970 * theory SetInterval: changed the syntax for open intervals:
  4971 
  4972   Old       New
  4973   {..n(}    {..<n}
  4974   {)n..}    {n<..}
  4975   {m..n(}   {m..<n}
  4976   {)m..n}   {m<..n}
  4977   {)m..n(}  {m<..<n}
  4978 
  4979 The old syntax is still supported but will disappear in the next
  4980 release.  For conversion use the following Emacs search and replace
  4981 patterns (these are not perfect but work quite well):
  4982 
  4983   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  4984   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  4985 
  4986 * Theory Commutative_Ring (in Library): method comm_ring for proving
  4987 equalities in commutative rings; method 'algebra' provides a generic
  4988 interface.
  4989 
  4990 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  4991 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  4992 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  4993 be a tuple pattern.
  4994 
  4995 Some new syntax forms are available:
  4996 
  4997   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  4998   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  4999   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  5000   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  5001 
  5002 The latter form "\<Sum>x < k. e" used to be based on a separate
  5003 function "Summation", which has been discontinued.
  5004 
  5005 * theory Finite_Set: in structured induction proofs, the insert case
  5006 is now 'case (insert x F)' instead of the old counterintuitive 'case
  5007 (insert F x)'.
  5008 
  5009 * The 'refute' command has been extended to support a much larger
  5010 fragment of HOL, including axiomatic type classes, constdefs and
  5011 typedefs, inductive datatypes and recursion.
  5012 
  5013 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  5014 Requires zChaff with proof generation to be installed.  See
  5015 HOL/ex/SAT_Examples.thy for examples.
  5016 
  5017 * Datatype induction via method 'induct' now preserves the name of the
  5018 induction variable. For example, when proving P(xs::'a list) by
  5019 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  5020 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  5021 in unstructured proof scripts.
  5022 
  5023 * Reworked implementation of records.  Improved scalability for
  5024 records with many fields, avoiding performance problems for type
  5025 inference. Records are no longer composed of nested field types, but
  5026 of nested extension types. Therefore the record type only grows linear
  5027 in the number of extensions and not in the number of fields.  The
  5028 top-level (users) view on records is preserved.  Potential
  5029 INCOMPATIBILITY only in strange cases, where the theory depends on the
  5030 old record representation. The type generated for a record is called
  5031 <record_name>_ext_type.
  5032 
  5033 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  5034 proofs triggered by a record definition or a simproc (if
  5035 quick_and_dirty is enabled).  Definitions of large records can take
  5036 quite long.
  5037 
  5038 New simproc record_upd_simproc for simplification of multiple record
  5039 updates enabled by default.  Moreover, trivial updates are also
  5040 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  5041 occasionally, since simplification is more powerful by default.
  5042 
  5043 * typedef: proper support for polymorphic sets, which contain extra
  5044 type-variables in the term.
  5045 
  5046 * Simplifier: automatically reasons about transitivity chains
  5047 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  5048 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  5049 old proofs break occasionally as simplification may now solve more
  5050 goals than previously.
  5051 
  5052 * Simplifier: converts x <= y into x = y if assumption y <= x is
  5053 present.  Works for all partial orders (class "order"), in particular
  5054 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  5055 just like y <= x.
  5056 
  5057 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  5058 bound variable or a constant then the let is unfolded.  Otherwise
  5059 first a is simplified to b, and then f b is simplified to g. If
  5060 possible we abstract b from g arriving at "let x = b in h x",
  5061 otherwise we unfold the let and arrive at g.  The simproc can be
  5062 enabled/disabled by the reference use_let_simproc.  Potential
  5063 INCOMPATIBILITY since simplification is more powerful by default.
  5064 
  5065 * Classical reasoning: the meson method now accepts theorems as arguments.
  5066 
  5067 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  5068 jobs to provide advice on the provability of subgoals.
  5069 
  5070 * Theory OrderedGroup and Ring_and_Field: various additions and
  5071 improvements to faciliate calculations involving equalities and
  5072 inequalities.
  5073 
  5074 The following theorems have been eliminated or modified
  5075 (INCOMPATIBILITY):
  5076 
  5077   abs_eq             now named abs_of_nonneg
  5078   abs_of_ge_0        now named abs_of_nonneg
  5079   abs_minus_eq       now named abs_of_nonpos
  5080   imp_abs_id         now named abs_of_nonneg
  5081   imp_abs_neg_id     now named abs_of_nonpos
  5082   mult_pos           now named mult_pos_pos
  5083   mult_pos_le        now named mult_nonneg_nonneg
  5084   mult_pos_neg_le    now named mult_nonneg_nonpos
  5085   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5086   mult_neg           now named mult_neg_neg
  5087   mult_neg_le        now named mult_nonpos_nonpos
  5088 
  5089 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5090      
  5091      zero_le_square
  5092      not_square_less_zero 
  5093 
  5094   The following lemmas have been deleted from Real/RealPow:
  5095   
  5096      realpow_zero_zero
  5097      realpow_two
  5098      realpow_less
  5099      zero_le_power
  5100      realpow_two_le
  5101      abs_realpow_two
  5102      realpow_two_abs     
  5103 
  5104 * Theory Parity: added rules for simplifying exponents.
  5105 
  5106 * Theory List:
  5107 
  5108 The following theorems have been eliminated or modified
  5109 (INCOMPATIBILITY):
  5110 
  5111   list_all_Nil       now named list_all.simps(1)
  5112   list_all_Cons      now named list_all.simps(2)
  5113   list_all_conv      now named list_all_iff
  5114   set_mem_eq         now named mem_iff
  5115 
  5116 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5117 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5118 
  5119 
  5120 *** HOL-Complex ***
  5121 
  5122 * Theory RealDef: better support for embedding natural numbers and
  5123 integers in the reals.
  5124 
  5125 The following theorems have been eliminated or modified
  5126 (INCOMPATIBILITY):
  5127 
  5128   exp_ge_add_one_self  now requires no hypotheses
  5129   real_of_int_add      reversed direction of equality (use [symmetric])
  5130   real_of_int_minus    reversed direction of equality (use [symmetric])
  5131   real_of_int_diff     reversed direction of equality (use [symmetric])
  5132   real_of_int_mult     reversed direction of equality (use [symmetric])
  5133 
  5134 * Theory RComplete: expanded support for floor and ceiling functions.
  5135 
  5136 * Theory Ln is new, with properties of the natural logarithm
  5137 
  5138 * Hyperreal: There is a new type constructor "star" for making
  5139 nonstandard types.  The old type names are now type synonyms:
  5140 
  5141   hypreal = real star
  5142   hypnat = nat star
  5143   hcomplex = complex star
  5144 
  5145 * Hyperreal: Many groups of similarly-defined constants have been
  5146 replaced by polymorphic versions (INCOMPATIBILITY):
  5147 
  5148   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5149 
  5150   starset      <-- starsetNat, starsetC
  5151   *s*          <-- *sNat*, *sc*
  5152   starset_n    <-- starsetNat_n, starsetC_n
  5153   *sn*         <-- *sNatn*, *scn*
  5154   InternalSets <-- InternalNatSets, InternalCSets
  5155 
  5156   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5157   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5158   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5159   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5160   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5161 
  5162 * Hyperreal: Many type-specific theorems have been removed in favor of
  5163 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5164 
  5165   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5166   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5167   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5168   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5169   right_minus <-- hypreal_add_minus
  5170   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5171   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5172   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5173   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5174   mult_1_right <-- hcomplex_mult_one_right
  5175   mult_zero_left <-- hcomplex_mult_zero_left
  5176   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5177   right_distrib <-- hypnat_add_mult_distrib2
  5178   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5179   right_inverse <-- hypreal_mult_inverse
  5180   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5181   order_refl <-- {hypreal,hypnat}_le_refl
  5182   order_trans <-- {hypreal,hypnat}_le_trans
  5183   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5184   order_less_le <-- {hypreal,hypnat}_less_le
  5185   linorder_linear <-- {hypreal,hypnat}_le_linear
  5186   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5187   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5188   add_nonneg_nonneg <-- hypreal_le_add_order
  5189 
  5190 * Hyperreal: Separate theorems having to do with type-specific
  5191 versions of constants have been merged into theorems that apply to the
  5192 new polymorphic constants (INCOMPATIBILITY):
  5193 
  5194   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5195   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5196   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5197   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5198   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5199   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5200   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5201   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5202   STAR_diff <-- {STAR,STARC}_diff
  5203   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5204     STARC_hcomplex_of_complex}_image_subset
  5205   starset_n_Un <-- starset{Nat,C}_n_Un
  5206   starset_n_Int <-- starset{Nat,C}_n_Int
  5207   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5208   starset_n_diff <-- starset{Nat,C}_n_diff
  5209   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5210   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5211   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5212   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5213   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5214   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5215   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5216   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5217   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5218   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5219   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5220   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5221   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5222   starfun_diff <-- starfun{C,RC,CR}_diff
  5223   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5224   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5225   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5226   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5227   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5228   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5229   starfun_Id <-- starfunC_Id
  5230   starfun_approx <-- starfun{Nat,CR}_approx
  5231   starfun_capprox <-- starfun{C,RC}_capprox
  5232   starfun_abs <-- starfunNat_rabs
  5233   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5234   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5235   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5236   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5237   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5238   starfun_add_approx <-- starfunCR_add_approx
  5239   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5240   starfun_divide <-- starfun{C,CR,RC}_divide
  5241   starfun_n <-- starfun{Nat,C}_n
  5242   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5243   starfun_n_add <-- starfun{Nat,C}_n_add
  5244   starfun_n_add_minus <-- starfunNat_n_add_minus
  5245   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5246   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5247   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5248 
  5249   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5250   star_n_minus <-- {hypreal,hcomplex}_minus
  5251   star_n_diff <-- {hypreal,hcomplex}_diff
  5252   star_n_mult <-- {hypreal,hcomplex}_mult
  5253   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5254   star_n_le <-- {hypreal,hypnat}_le
  5255   star_n_less <-- {hypreal,hypnat}_less
  5256   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5257   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5258   star_n_abs <-- hypreal_hrabs
  5259   star_n_divide <-- hcomplex_divide
  5260 
  5261   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5262   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5263   star_of_diff <-- hypreal_of_real_diff
  5264   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5265   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5266   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5267   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5268   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5269   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5270   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5271   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5272   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5273   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5274   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5275   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5276   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5277   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5278   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5279   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5280   star_of_power <-- hypreal_of_real_power
  5281   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5282 
  5283 * Hyperreal: new method "transfer" that implements the transfer
  5284 principle of nonstandard analysis. With a subgoal that mentions
  5285 nonstandard types like "'a star", the command "apply transfer"
  5286 replaces it with an equivalent one that mentions only standard types.
  5287 To be successful, all free variables must have standard types; non-
  5288 standard variables must have explicit universal quantifiers.
  5289 
  5290 * Hyperreal: A theory of Taylor series.
  5291 
  5292 
  5293 *** HOLCF ***
  5294 
  5295 * Discontinued special version of 'constdefs' (which used to support
  5296 continuous functions) in favor of the general Pure one with full
  5297 type-inference.
  5298 
  5299 * New simplification procedure for solving continuity conditions; it
  5300 is much faster on terms with many nested lambda abstractions (cubic
  5301 instead of exponential time).
  5302 
  5303 * New syntax for domain package: selector names are now optional.
  5304 Parentheses should be omitted unless argument is lazy, for example:
  5305 
  5306   domain 'a stream = cons "'a" (lazy "'a stream")
  5307 
  5308 * New command 'fixrec' for defining recursive functions with pattern
  5309 matching; defining multiple functions with mutual recursion is also
  5310 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5311 sinr, or any data constructor defined by the domain package. The given
  5312 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5313 syntax and examples.
  5314 
  5315 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5316 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5317 but the proof obligation additionally includes an admissibility
  5318 requirement. The packages generate instances of class cpo or pcpo,
  5319 with continuity and strictness theorems for Rep and Abs.
  5320 
  5321 * HOLCF: Many theorems have been renamed according to a more standard naming
  5322 scheme (INCOMPATIBILITY):
  5323 
  5324   foo_inject:  "foo$x = foo$y ==> x = y"
  5325   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5326   foo_less:    "(foo$x << foo$y) = (x << y)"
  5327   foo_strict:  "foo$UU = UU"
  5328   foo_defined: "... ==> foo$x ~= UU"
  5329   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5330 
  5331 
  5332 *** ZF ***
  5333 
  5334 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5335 including the First Isomorphism Theorem (on quotienting by the kernel
  5336 of a homomorphism).
  5337 
  5338 * ZF/Simplifier: install second copy of type solver that actually
  5339 makes use of TC rules declared to Isar proof contexts (or locales);
  5340 the old version is still required for ML proof scripts.
  5341 
  5342 
  5343 *** Cube ***
  5344 
  5345 * Converted to Isar theory format; use locales instead of axiomatic
  5346 theories.
  5347 
  5348 
  5349 *** ML ***
  5350 
  5351 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5352 for ||>, ||>>, |>>,
  5353 
  5354 * Pure/library.ML no longer defines its own option datatype, but uses
  5355 that of the SML basis, which has constructors NONE and SOME instead of
  5356 None and Some, as well as exception Option.Option instead of OPTION.
  5357 The functions the, if_none, is_some, is_none have been adapted
  5358 accordingly, while Option.map replaces apsome.
  5359 
  5360 * Pure/library.ML: the exception LIST has been given up in favour of
  5361 the standard exceptions Empty and Subscript, as well as
  5362 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5363 superceded by the standard hd and tl functions etc.
  5364 
  5365 A number of basic list functions are no longer exported to the ML
  5366 toplevel, as they are variants of predefined functions.  The following
  5367 suggests how one can translate existing code:
  5368 
  5369     rev_append xs ys = List.revAppend (xs, ys)
  5370     nth_elem (i, xs) = List.nth (xs, i)
  5371     last_elem xs = List.last xs
  5372     flat xss = List.concat xss
  5373     seq fs = List.app fs
  5374     partition P xs = List.partition P xs
  5375     mapfilter f xs = List.mapPartial f xs
  5376 
  5377 * Pure/library.ML: several combinators for linear functional
  5378 transformations, notably reverse application and composition:
  5379 
  5380   x |> f                f #> g
  5381   (x, y) |-> f          f #-> g
  5382 
  5383 * Pure/library.ML: introduced/changed precedence of infix operators:
  5384 
  5385   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5386   infix 2 ?;
  5387   infix 3 o oo ooo oooo;
  5388   infix 4 ~~ upto downto;
  5389 
  5390 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5391 infix operators.
  5392 
  5393 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5394 fold_map support linear functional transformations and nesting.  For
  5395 example:
  5396 
  5397   fold f [x1, ..., xN] y =
  5398     y |> f x1 |> ... |> f xN
  5399 
  5400   (fold o fold) f [xs1, ..., xsN] y =
  5401     y |> fold f xs1 |> ... |> fold f xsN
  5402 
  5403   fold f [x1, ..., xN] =
  5404     f x1 #> ... #> f xN
  5405 
  5406   (fold o fold) f [xs1, ..., xsN] =
  5407     fold f xs1 #> ... #> fold f xsN
  5408 
  5409 * Pure/library.ML: the following selectors on type 'a option are
  5410 available:
  5411 
  5412   the:               'a option -> 'a  (*partial*)
  5413   these:             'a option -> 'a  where 'a = 'b list
  5414   the_default: 'a -> 'a option -> 'a
  5415   the_list:          'a option -> 'a list
  5416 
  5417 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5418 basic operations for association lists, following natural argument
  5419 order; moreover the explicit equality predicate passed here avoids
  5420 potentially expensive polymorphic runtime equality checks.
  5421 The old functions may be expressed as follows:
  5422 
  5423   assoc = uncurry (AList.lookup (op =))
  5424   assocs = these oo AList.lookup (op =)
  5425   overwrite = uncurry (AList.update (op =)) o swap
  5426 
  5427 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5428 
  5429   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5430   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5431 
  5432 replacing make_keylist and keyfilter (occassionally used)
  5433 Naive rewrites:
  5434 
  5435   make_keylist = AList.make
  5436   keyfilter = AList.find (op =)
  5437 
  5438 * eq_fst and eq_snd now take explicit equality parameter, thus
  5439   avoiding eqtypes. Naive rewrites:
  5440 
  5441     eq_fst = eq_fst (op =)
  5442     eq_snd = eq_snd (op =)
  5443 
  5444 * Removed deprecated apl and apr (rarely used).
  5445   Naive rewrites:
  5446 
  5447     apl (n, op) =>>= curry op n
  5448     apr (op, m) =>>= fn n => op (n, m)
  5449 
  5450 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5451 provides a reasonably efficient light-weight implementation of sets as
  5452 lists.
  5453 
  5454 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5455 few new operations; existing lookup and update are now curried to
  5456 follow natural argument order (for use with fold etc.);
  5457 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5458 
  5459 * Pure/General: output via the Isabelle channels of
  5460 writeln/warning/error etc. is now passed through Output.output, with a
  5461 hook for arbitrary transformations depending on the print_mode
  5462 (cf. Output.add_mode -- the first active mode that provides a output
  5463 function wins).  Already formatted output may be embedded into further
  5464 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5465 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5466 accommodate easy composition of diagnostic messages etc.  Programmers
  5467 rarely need to care about Output.output or Output.raw at all, with
  5468 some notable exceptions: Output.output is required when bypassing the
  5469 standard channels (writeln etc.), or in token translations to produce
  5470 properly formatted results; Output.raw is required when capturing
  5471 already output material that will eventually be presented to the user
  5472 a second time.  For the default print mode, both Output.output and
  5473 Output.raw have no effect.
  5474 
  5475 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5476 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5477 cumulative results are displayed at the end of a batch session.
  5478 
  5479 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5480 replaced by File.platform_path and File.shell_path (with appropriate
  5481 hooks).  This provides a clean interface for unusual systems where the
  5482 internal and external process view of file names are different.
  5483 
  5484 * Pure: more efficient orders for basic syntactic entities: added
  5485 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5486 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5487 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5488 orders now -- potential INCOMPATIBILITY for code that depends on a
  5489 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5490 Library.sort_strings on result).
  5491 
  5492 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5493 fold_types traverse types/terms from left to right, observing natural
  5494 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5495 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5496 
  5497 * Pure: name spaces have been refined, with significant changes of the
  5498 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5499 to extern(_table).  The plain name entry path is superceded by a
  5500 general 'naming' context, which also includes the 'policy' to produce
  5501 a fully qualified name and external accesses of a fully qualified
  5502 name; NameSpace.extend is superceded by context dependent
  5503 Sign.declare_name.  Several theory and proof context operations modify
  5504 the naming context.  Especially note Theory.restore_naming and
  5505 ProofContext.restore_naming to get back to a sane state; note that
  5506 Theory.add_path is no longer sufficient to recover from
  5507 Theory.absolute_path in particular.
  5508 
  5509 * Pure: new flags short_names (default false) and unique_names
  5510 (default true) for controlling output of qualified names.  If
  5511 short_names is set, names are printed unqualified.  If unique_names is
  5512 reset, the name prefix is reduced to the minimum required to achieve
  5513 the original result when interning again, even if there is an overlap
  5514 with earlier declarations.
  5515 
  5516 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5517 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5518 (useful for printing error messages).  INCOMPATIBILITY.
  5519 
  5520 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5521 Theory.theory are now identified, referring to the universal
  5522 Context.theory (see Pure/context.ML).  Actual signature and theory
  5523 content is managed as theory data.  The old code and interfaces were
  5524 spread over many files and structures; the new arrangement introduces
  5525 considerable INCOMPATIBILITY to gain more clarity:
  5526 
  5527   Context -- theory management operations (name, identity, inclusion,
  5528     parents, ancestors, merge, etc.), plus generic theory data;
  5529 
  5530   Sign -- logical signature and syntax operations (declaring consts,
  5531     types, etc.), plus certify/read for common entities;
  5532 
  5533   Theory -- logical theory operations (stating axioms, definitions,
  5534     oracles), plus a copy of logical signature operations (consts,
  5535     types, etc.); also a few basic management operations (Theory.copy,
  5536     Theory.merge, etc.)
  5537 
  5538 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5539 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5540 for convenience -- they merely return the theory.
  5541 
  5542 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5543 
  5544 * Pure: the Isar proof context type is already defined early in Pure
  5545 as Context.proof (note that ProofContext.context and Proof.context are
  5546 aliases, where the latter is the preferred name).  This enables other
  5547 Isabelle components to refer to that type even before Isar is present.
  5548 
  5549 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5550 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5551 any of these kinds.  For example, Sign.intern typeK is now
  5552 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5553 Theory.hide_types.  Also note that former
  5554 Theory.hide_classes/types/consts are now
  5555 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5556 internalize their arguments!  INCOMPATIBILITY.
  5557 
  5558 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5559 datatype thmref (with constructors Name and NameSelection) instead of
  5560 plain string -- INCOMPATIBILITY;
  5561 
  5562 * Pure: cases produced by proof methods specify options, where NONE
  5563 means to remove case bindings -- INCOMPATIBILITY in
  5564 (RAW_)METHOD_CASES.
  5565 
  5566 * Pure: the following operations retrieve axioms or theorems from a
  5567 theory node or theory hierarchy, respectively:
  5568 
  5569   Theory.axioms_of: theory -> (string * term) list
  5570   Theory.all_axioms_of: theory -> (string * term) list
  5571   PureThy.thms_of: theory -> (string * thm) list
  5572   PureThy.all_thms_of: theory -> (string * thm) list
  5573 
  5574 * Pure: print_tac now outputs the goal through the trace channel.
  5575 
  5576 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5577 Reference Toplevel.debug (default false) controls detailed printing
  5578 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5579 controls execution profiling -- set to 1 for time and 2 for space
  5580 (both increase the runtime).
  5581 
  5582 * Isar session: The initial use of ROOT.ML is now always timed,
  5583 i.e. the log will show the actual process times, in contrast to the
  5584 elapsed wall-clock time that the outer shell wrapper produces.
  5585 
  5586 * Simplifier: improved handling of bound variables (nameless
  5587 representation, avoid allocating new strings).  Simprocs that invoke
  5588 the Simplifier recursively should use Simplifier.inherit_bounds to
  5589 avoid local name clashes.  Failure to do so produces warnings
  5590 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5591 for further details.
  5592 
  5593 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5594 bindings for all theorems stored within a given theory; this may help
  5595 in porting non-Isar theories to Isar ones, while keeping ML proof
  5596 scripts for the time being.
  5597 
  5598 * ML operator HTML.with_charset specifies the charset begin used for
  5599 generated HTML files.  For example:
  5600 
  5601   HTML.with_charset "utf-8" use_thy "Hebrew";
  5602   HTML.with_charset "utf-8" use_thy "Chinese";
  5603 
  5604 
  5605 *** System ***
  5606 
  5607 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5608 isabelle, isatool etc.).
  5609 
  5610 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5611 isatool doc, isatool mkdir, display_drafts etc.).
  5612 
  5613 * isatool usedir: option -f allows specification of the ML file to be
  5614 used by Isabelle; default is ROOT.ML.
  5615 
  5616 * New isatool version outputs the version identifier of the Isabelle
  5617 distribution being used.
  5618 
  5619 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5620 (containing Boolean satisfiability problems) into Isabelle/HOL
  5621 theories.
  5622 
  5623 
  5624 
  5625 New in Isabelle2004 (April 2004)
  5626 --------------------------------
  5627 
  5628 *** General ***
  5629 
  5630 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5631   Replaces linorder.ML.
  5632 
  5633 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5634   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5635   (\<a>...\<z>), are now considered normal letters, and can therefore
  5636   be used anywhere where an ASCII letter (a...zA...Z) has until
  5637   now. COMPATIBILITY: This obviously changes the parsing of some
  5638   terms, especially where a symbol has been used as a binder, say
  5639   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5640   as an identifier.  Fix it by inserting a space around former
  5641   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5642   existing theory and ML files.
  5643 
  5644 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5645 
  5646 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5647   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5648   a normal (but invisible) letter. For multiple letter subscripts repeat
  5649   \<^isub> like this: x\<^isub>1\<^isub>2.
  5650 
  5651 * Pure: There are now sub-/superscripts that can span more than one
  5652   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5653   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5654   superscript. The new control characters are not identifier parts.
  5655 
  5656 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5657   content of "..." to the latex file instead of \isacntrl... . The "..."
  5658   may consist of any printable characters excluding the end bracket >.
  5659 
  5660 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5661   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5662   declare constants "final", which prevents their being given a definition
  5663   later.  It is useful for constants whose behaviour is fixed axiomatically
  5664   rather than definitionally, such as the meta-logic connectives.
  5665 
  5666 * Pure: 'instance' now handles general arities with general sorts
  5667   (i.e. intersections of classes),
  5668 
  5669 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5670   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5671   It can be changed to alter the colors/layout of generated pages.
  5672 
  5673 
  5674 *** Isar ***
  5675 
  5676 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5677   cut_tac, subgoal_tac and thin_tac:
  5678   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5679     locales are no longer forced to write Isar proof scripts.
  5680     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5681     emulations.
  5682   - INCOMPATIBILITY: names of variables to be instantiated may no
  5683     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5684     This is consistent with the instantiation attribute "where".
  5685 
  5686 * Attributes "where" and "of":
  5687   - Now take type variables of instantiated theorem into account when reading
  5688     the instantiation string.  This fixes a bug that caused instantiated
  5689     theorems to have too special types in some circumstances.
  5690   - "where" permits explicit instantiations of type variables.
  5691 
  5692 * Calculation commands "moreover" and "also" no longer interfere with
  5693   current facts ("this"), admitting arbitrary combinations with "then"
  5694   and derived forms.
  5695 
  5696 * Locales:
  5697   - Goal statements involving the context element "includes" no longer
  5698     generate theorems with internal delta predicates (those ending on
  5699     "_axioms") in the premise.
  5700     Resolve particular premise with <locale>.intro to obtain old form.
  5701   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5702     specification and "includes" elements in goal statement.
  5703   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5704     [intro?] and [elim?] (respectively) by default.
  5705   - Experimental command for instantiation of locales in proof contexts:
  5706         instantiate <label>[<attrs>]: <loc>
  5707     Instantiates locale <loc> and adds all its theorems to the current context
  5708     taking into account their attributes.  Label and attrs are optional
  5709     modifiers, like in theorem declarations.  If present, names of
  5710     instantiated theorems are qualified with <label>, and the attributes
  5711     <attrs> are applied after any attributes these theorems might have already.
  5712       If the locale has assumptions, a chained fact of the form
  5713     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5714     are derived.  The command does not support old-style locales declared
  5715     with "locale (open)".
  5716       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5717 
  5718 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5719   (Isar) contexts.
  5720 
  5721 
  5722 *** HOL ***
  5723 
  5724 * Proof import: new image HOL4 contains the imported library from
  5725   the HOL4 system with about 2500 theorems. It is imported by
  5726   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5727   can be used like any other Isabelle image.  See
  5728   HOL/Import/HOL/README for more information.
  5729 
  5730 * Simplifier:
  5731   - Much improved handling of linear and partial orders.
  5732     Reasoners for linear and partial orders are set up for type classes
  5733     "linorder" and "order" respectively, and are added to the default simpset
  5734     as solvers.  This means that the simplifier can build transitivity chains
  5735     to solve goals from the assumptions.
  5736   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5737     of blast or auto after simplification become unnecessary because the goal
  5738     is solved by simplification already.
  5739 
  5740 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5741     all proved in axiomatic type classes for semirings, rings and fields.
  5742 
  5743 * Numerics:
  5744   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5745     now formalized using the Ring_and_Field theory mentioned above.
  5746   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5747     than before, because now they are set up once in a generic manner.
  5748   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5749     Look for the general versions in Ring_and_Field (and Power if they concern
  5750     exponentiation).
  5751 
  5752 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5753 
  5754 * Records:
  5755   - Record types are now by default printed with their type abbreviation
  5756     instead of the list of all field types. This can be configured via
  5757     the reference "print_record_type_abbr".
  5758   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5759     (not enabled by default).
  5760   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5761     EX x. x = sel r to True (not enabled by default).
  5762   - Tactic "record_split_simp_tac" to split and simplify records added.
  5763 
  5764 * 'specification' command added, allowing for definition by
  5765   specification.  There is also an 'ax_specification' command that
  5766   introduces the new constants axiomatically.
  5767 
  5768 * arith(_tac) is now able to generate counterexamples for reals as well.
  5769 
  5770 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5771 
  5772 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5773   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5774 
  5775 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5776   matrix theory to linear programming.
  5777 
  5778 * Unions and Intersections:
  5779   The latex output syntax of UN and INT has been changed
  5780   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5781   i.e. the index formulae has become a subscript.
  5782   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5783 
  5784 * Unions and Intersections over Intervals:
  5785   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5786   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5787   like in normal math, and corresponding versions for < and for intersection.
  5788 
  5789 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5790   lexicographic dictonary ordering has been added as "lexord".
  5791 
  5792 * ML: the legacy theory structures Int and List have been removed. They had
  5793   conflicted with ML Basis Library structures having the same names.
  5794 
  5795 * 'refute' command added to search for (finite) countermodels.  Only works
  5796   for a fragment of HOL.  The installation of an external SAT solver is
  5797   highly recommended.  See "HOL/Refute.thy" for details.
  5798 
  5799 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5800   formulae under an assignment of free variables to random values.
  5801   In contrast to 'refute', it can deal with inductive datatypes,
  5802   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5803   for examples.
  5804 
  5805 
  5806 *** HOLCF ***
  5807 
  5808 * Streams now come with concatenation and are part of the HOLCF image
  5809 
  5810 
  5811 
  5812 New in Isabelle2003 (May 2003)
  5813 ------------------------------
  5814 
  5815 *** General ***
  5816 
  5817 * Provers/simplifier:
  5818 
  5819   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5820     Assumptions are now subject to complete mutual simplification,
  5821     not just from left to right. The simplifier now preserves
  5822     the order of assumptions.
  5823 
  5824     Potential INCOMPATIBILITY:
  5825 
  5826     -- simp sometimes diverges where the old version did
  5827        not, e.g. invoking simp on the goal
  5828 
  5829         [| P (f x); y = x; f x = f y |] ==> Q
  5830 
  5831        now gives rise to the infinite reduction sequence
  5832 
  5833         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5834 
  5835        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5836        kind of problem.
  5837 
  5838     -- Tactics combining classical reasoner and simplification (such as auto)
  5839        are also affected by this change, because many of them rely on
  5840        simp. They may sometimes diverge as well or yield a different numbers
  5841        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5842        in case of problems. Sometimes subsequent calls to the classical
  5843        reasoner will fail because a preceeding call to the simplifier too
  5844        eagerly simplified the goal, e.g. deleted redundant premises.
  5845 
  5846   - The simplifier trace now shows the names of the applied rewrite rules
  5847 
  5848   - You can limit the number of recursive invocations of the simplifier
  5849     during conditional rewriting (where the simplifie tries to solve the
  5850     conditions before applying the rewrite rule):
  5851     ML "simp_depth_limit := n"
  5852     where n is an integer. Thus you can force termination where previously
  5853     the simplifier would diverge.
  5854 
  5855   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5856 
  5857   - No longer aborts on failed congruence proof.  Instead, the
  5858     congruence is ignored.
  5859 
  5860 * Pure: New generic framework for extracting programs from constructive
  5861   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5862   as HOL/Extraction for some case studies.
  5863 
  5864 * Pure: The main goal of the proof state is no longer shown by default, only
  5865 the subgoals. This behaviour is controlled by a new flag.
  5866    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5867 (ML: Proof.show_main_goal).
  5868 
  5869 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5870 rules whose conclusion matches subgoal 1:
  5871       PG menu: Isabelle/Isar -> Show me -> matching rules
  5872 The rules are ordered by how closely they match the subgoal.
  5873 In particular, rules that solve a subgoal outright are displayed first
  5874 (or rather last, the way they are printed).
  5875 (ML: ProofGeneral.print_intros())
  5876 
  5877 * Pure: New flag trace_unify_fail causes unification to print
  5878 diagnostic information (PG: in trace buffer) when it fails. This is
  5879 useful for figuring out why single step proofs like rule, erule or
  5880 assumption failed.
  5881 
  5882 * Pure: Locale specifications now produce predicate definitions
  5883 according to the body of text (covering assumptions modulo local
  5884 definitions); predicate "loc_axioms" covers newly introduced text,
  5885 while "loc" is cumulative wrt. all included locale expressions; the
  5886 latter view is presented only on export into the global theory
  5887 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5888 on the old view without predicates;
  5889 
  5890 * Pure: predefined locales "var" and "struct" are useful for sharing
  5891 parameters (as in CASL, for example); just specify something like
  5892 ``var x + var y + struct M'' as import;
  5893 
  5894 * Pure: improved thms_containing: proper indexing of facts instead of
  5895 raw theorems; check validity of results wrt. current name space;
  5896 include local facts of proof configuration (also covers active
  5897 locales), cover fixed variables in index; may use "_" in term
  5898 specification; an optional limit for the number of printed facts may
  5899 be given (the default is 40);
  5900 
  5901 * Pure: disallow duplicate fact bindings within new-style theory files
  5902 (batch-mode only);
  5903 
  5904 * Provers: improved induct method: assumptions introduced by case
  5905 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5906 the goal statement); "foo" still refers to all facts collectively;
  5907 
  5908 * Provers: the function blast.overloaded has been removed: all constants
  5909 are regarded as potentially overloaded, which improves robustness in exchange
  5910 for slight decrease in efficiency;
  5911 
  5912 * Provers/linorder: New generic prover for transitivity reasoning over
  5913 linear orders.  Note: this prover is not efficient!
  5914 
  5915 * Isar: preview of problems to finish 'show' now produce an error
  5916 rather than just a warning (in interactive mode);
  5917 
  5918 
  5919 *** HOL ***
  5920 
  5921 * arith(_tac)
  5922 
  5923  - Produces a counter example if it cannot prove a goal.
  5924    Note that the counter example may be spurious if the goal is not a formula
  5925    of quantifier-free linear arithmetic.
  5926    In ProofGeneral the counter example appears in the trace buffer.
  5927 
  5928  - Knows about div k and mod k where k is a numeral of type nat or int.
  5929 
  5930  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5931    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5932    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5933 
  5934 * simp's arithmetic capabilities have been enhanced a bit: it now
  5935 takes ~= in premises into account (by performing a case split);
  5936 
  5937 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5938 are distributed over a sum of terms;
  5939 
  5940 * New tactic "trans_tac" and method "trans" instantiate
  5941 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5942 "<=", "<" and "=").
  5943 
  5944 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5945 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5946 
  5947 * 'typedef' command has new option "open" to suppress the set
  5948 definition;
  5949 
  5950 * functions Min and Max on finite sets have been introduced (theory
  5951 Finite_Set);
  5952 
  5953 * attribute [symmetric] now works for relations as well; it turns
  5954 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5955 
  5956 * induct over a !!-quantified statement (say !!x1..xn):
  5957   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5958 
  5959 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5960 %x. None. Warning: empty_def now refers to the previously hidden definition
  5961 of the empty set.
  5962 
  5963 * Algebra: formalization of classical algebra.  Intended as base for
  5964 any algebraic development in Isabelle.  Currently covers group theory
  5965 (up to Sylow's theorem) and ring theory (Universal Property of
  5966 Univariate Polynomials).  Contributions welcome;
  5967 
  5968 * GroupTheory: deleted, since its material has been moved to Algebra;
  5969 
  5970 * Complex: new directory of the complex numbers with numeric constants,
  5971 nonstandard complex numbers, and some complex analysis, standard and
  5972 nonstandard (Jacques Fleuriot);
  5973 
  5974 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  5975 
  5976 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  5977 Fleuriot);
  5978 
  5979 * Real/HahnBanach: updated and adapted to locales;
  5980 
  5981 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  5982 Gray and Kramer);
  5983 
  5984 * UNITY: added the Meier-Sanders theory of progress sets;
  5985 
  5986 * MicroJava: bytecode verifier and lightweight bytecode verifier
  5987 as abstract algorithms, instantiated to the JVM;
  5988 
  5989 * Bali: Java source language formalization. Type system, operational
  5990 semantics, axiomatic semantics. Supported language features:
  5991 classes, interfaces, objects,virtual methods, static methods,
  5992 static/instance fields, arrays, access modifiers, definite
  5993 assignment, exceptions.
  5994 
  5995 
  5996 *** ZF ***
  5997 
  5998 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  5999 universe, etc.);
  6000 
  6001 * Main ZF: virtually all theories converted to new-style format;
  6002 
  6003 
  6004 *** ML ***
  6005 
  6006 * Pure: Tactic.prove provides sane interface for internal proofs;
  6007 omits the infamous "standard" operation, so this is more appropriate
  6008 than prove_goalw_cterm in many situations (e.g. in simprocs);
  6009 
  6010 * Pure: improved error reporting of simprocs;
  6011 
  6012 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  6013 up simprocs;
  6014 
  6015 
  6016 *** Document preparation ***
  6017 
  6018 * uses \par instead of \\ for line breaks in theory text. This may
  6019 shift some page breaks in large documents. To get the old behaviour
  6020 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  6021 
  6022 * minimized dependencies of isabelle.sty and isabellesym.sty on
  6023 other packages
  6024 
  6025 * \<euro> now needs package babel/greek instead of marvosym (which
  6026 broke \Rightarrow)
  6027 
  6028 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  6029 textcomp package)
  6030 
  6031 
  6032 
  6033 New in Isabelle2002 (March 2002)
  6034 --------------------------------
  6035 
  6036 *** Document preparation ***
  6037 
  6038 * greatly simplified document preparation setup, including more
  6039 graceful interpretation of isatool usedir -i/-d/-D options, and more
  6040 instructive isatool mkdir; users should basically be able to get
  6041 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  6042 users may run a separate document processing stage manually like this:
  6043 "isatool usedir -D output HOL Test && isatool document Test/output";
  6044 
  6045 * theory dependency graph may now be incorporated into documents;
  6046 isatool usedir -g true will produce session_graph.eps/.pdf for use
  6047 with \includegraphics of LaTeX;
  6048 
  6049 * proper spacing of consecutive markup elements, especially text
  6050 blocks after section headings;
  6051 
  6052 * support bold style (for single symbols only), input syntax is like
  6053 this: "\<^bold>\<alpha>" or "\<^bold>A";
  6054 
  6055 * \<bullet> is now output as bold \cdot by default, which looks much
  6056 better in printed text;
  6057 
  6058 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  6059 note that these symbols are currently unavailable in Proof General /
  6060 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  6061 
  6062 * isatool latex no longer depends on changed TEXINPUTS, instead
  6063 isatool document copies the Isabelle style files to the target
  6064 location;
  6065 
  6066 
  6067 *** Isar ***
  6068 
  6069 * Pure/Provers: improved proof by cases and induction;
  6070   - 'case' command admits impromptu naming of parameters (such as
  6071     "case (Suc n)");
  6072   - 'induct' method divinates rule instantiation from the inductive
  6073     claim; no longer requires excessive ?P bindings for proper
  6074     instantiation of cases;
  6075   - 'induct' method properly enumerates all possibilities of set/type
  6076     rules; as a consequence facts may be also passed through *type*
  6077     rules without further ado;
  6078   - 'induct' method now derives symbolic cases from the *rulified*
  6079     rule (before it used to rulify cases stemming from the internal
  6080     atomized version); this means that the context of a non-atomic
  6081     statement becomes is included in the hypothesis, avoiding the
  6082     slightly cumbersome show "PROP ?case" form;
  6083   - 'induct' may now use elim-style induction rules without chaining
  6084     facts, using ``missing'' premises from the goal state; this allows
  6085     rules stemming from inductive sets to be applied in unstructured
  6086     scripts, while still benefitting from proper handling of non-atomic
  6087     statements; NB: major inductive premises need to be put first, all
  6088     the rest of the goal is passed through the induction;
  6089   - 'induct' proper support for mutual induction involving non-atomic
  6090     rule statements (uses the new concept of simultaneous goals, see
  6091     below);
  6092   - append all possible rule selections, but only use the first
  6093     success (no backtracking);
  6094   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  6095   - undeclared rule case names default to numbers 1, 2, 3, ...;
  6096   - added 'print_induct_rules' (covered by help item in recent Proof
  6097     General versions);
  6098   - moved induct/cases attributes to Pure, methods to Provers;
  6099   - generic method setup instantiated for FOL and HOL;
  6100 
  6101 * Pure: support multiple simultaneous goal statements, for example
  6102 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  6103 meta-level mechanism, this acts as if several individual goals had
  6104 been stated separately; in particular common proof methods need to be
  6105 repeated in order to cover all claims; note that a single elimination
  6106 step is *not* sufficient to establish the two conjunctions, so this
  6107 fails:
  6108 
  6109   assume "A & B" then have A and B ..   (*".." fails*)
  6110 
  6111 better use "obtain" in situations as above; alternative refer to
  6112 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  6113 
  6114 * Pure: proper integration with ``locales''; unlike the original
  6115 version by Florian Kammller, Isar locales package high-level proof
  6116 contexts rather than raw logical ones (e.g. we admit to include
  6117 attributes everywhere); operations on locales include merge and
  6118 rename; support for implicit arguments (``structures''); simultaneous
  6119 type-inference over imports and text; see also HOL/ex/Locales.thy for
  6120 some examples;
  6121 
  6122 * Pure: the following commands have been ``localized'', supporting a
  6123 target locale specification "(in name)": 'lemma', 'theorem',
  6124 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  6125 stored both within the locale and at the theory level (exported and
  6126 qualified by the locale name);
  6127 
  6128 * Pure: theory goals may now be specified in ``long'' form, with
  6129 ad-hoc contexts consisting of arbitrary locale elements. for example
  6130 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  6131 definitions may be given, too); the result is a meta-level rule with
  6132 the context elements being discharged in the obvious way;
  6133 
  6134 * Pure: new proof command 'using' allows to augment currently used
  6135 facts after a goal statement ('using' is syntactically analogous to
  6136 'apply', but acts on the goal's facts only); this allows chained facts
  6137 to be separated into parts given before and after a claim, as in
  6138 ``from a and b have C using d and e <proof>'';
  6139 
  6140 * Pure: renamed "antecedent" case to "rule_context";
  6141 
  6142 * Pure: new 'judgment' command records explicit information about the
  6143 object-logic embedding (used by several tools internally); no longer
  6144 use hard-wired "Trueprop";
  6145 
  6146 * Pure: added 'corollary' command;
  6147 
  6148 * Pure: fixed 'token_translation' command;
  6149 
  6150 * Pure: removed obsolete 'exported' attribute;
  6151 
  6152 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  6153 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  6154 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  6155 
  6156 * Pure: method 'atomize' presents local goal premises as object-level
  6157 statements (atomic meta-level propositions); setup controlled via
  6158 rewrite rules declarations of 'atomize' attribute; example
  6159 application: 'induct' method with proper rule statements in improper
  6160 proof *scripts*;
  6161 
  6162 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  6163 now consider the syntactic context of assumptions, giving a better
  6164 chance to get type-inference of the arguments right (this is
  6165 especially important for locales);
  6166 
  6167 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  6168 mode;
  6169 
  6170 * Pure/obtain: the formal conclusion "thesis", being marked as
  6171 ``internal'', may no longer be reference directly in the text;
  6172 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  6173 situations;
  6174 
  6175 * Pure: generic 'sym' attribute which declares a rule both as pure
  6176 'elim?' and for the 'symmetric' operation;
  6177 
  6178 * Pure: marginal comments ``--'' may now occur just anywhere in the
  6179 text; the fixed correlation with particular command syntax has been
  6180 discontinued;
  6181 
  6182 * Pure: new method 'rules' is particularly well-suited for proof
  6183 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  6184 but often produces more compact proof terms with less detours;
  6185 
  6186 * Pure/Provers/classical: simplified integration with pure rule
  6187 attributes and methods; the classical "intro?/elim?/dest?"
  6188 declarations coincide with the pure ones; the "rule" method no longer
  6189 includes classically swapped intros; "intro" and "elim" methods no
  6190 longer pick rules from the context; also got rid of ML declarations
  6191 AddXIs/AddXEs/AddXDs; all of this has some potential for
  6192 INCOMPATIBILITY;
  6193 
  6194 * Provers/classical: attribute 'swapped' produces classical inversions
  6195 of introduction rules;
  6196 
  6197 * Provers/simplifier: 'simplified' attribute may refer to explicit
  6198 rules instead of full simplifier context; 'iff' attribute handles
  6199 conditional rules;
  6200 
  6201 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  6202 
  6203 * HOL: 'recdef' now fails on unfinished automated proofs, use
  6204 "(permissive)" option to recover old behavior;
  6205 
  6206 * HOL: 'inductive' no longer features separate (collective) attributes
  6207 for 'intros' (was found too confusing);
  6208 
  6209 * HOL: properly declared induction rules less_induct and
  6210 wf_induct_rule;
  6211 
  6212 
  6213 *** HOL ***
  6214 
  6215 * HOL: moved over to sane numeral syntax; the new policy is as
  6216 follows:
  6217 
  6218   - 0 and 1 are polymorphic constants, which are defined on any
  6219   numeric type (nat, int, real etc.);
  6220 
  6221   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  6222   binary representation internally;
  6223 
  6224   - type nat has special constructor Suc, and generally prefers Suc 0
  6225   over 1::nat and Suc (Suc 0) over 2::nat;
  6226 
  6227 This change may cause significant problems of INCOMPATIBILITY; here
  6228 are some hints on converting existing sources:
  6229 
  6230   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  6231   entities, so expressions involving "-" (unary or binary minus) need
  6232   to be spaced properly;