NEWS
author blanchet
Fri, 18 Mar 2011 22:55:28 +0100
changeset 42870 3c029ef9e0f2
parent 42864 bd6296de1432
child 42886 7b6e72a1b7dd
permissions -rw-r--r--
added "simp:", "intro:", and "elim:" to "try" command
     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) is has been
    26 discontinued.  INCOMPATIBILITY.
    27 
    28 * Various optional external tools are referenced more robustly and
    29 uniformly by explicit Isabelle settings as follows:
    30 
    31   ISABELLE_CSDP   (formerly CSDP_EXE)
    32   ISABELLE_GHC    (formerly EXEC_GHC or GHC_PATH)
    33   ISABELLE_OCAML  (formerly EXEC_OCAML)
    34   ISABELLE_SWIPL  (formerly EXEC_SWIPL)
    35   ISABELLE_YAP    (formerly EXEC_YAP)
    36 
    37 Note that automated detection from the file-system or search path has
    38 been discontinued.  INCOMPATIBILITY.
    39 
    40 
    41 *** HOL ***
    42 
    43 * Nitpick:
    44   - Added "need" and "total_consts" options.
    45   - Reintroduced "show_skolems" option by popular demand.
    46   - Renamed attribute: nitpick_def ~> nitpick_unfold.
    47     INCOMPATIBILITY.
    48 
    49 * Sledgehammer:
    50   - sledgehammer available_provers ~> sledgehammer supported_provers
    51     INCOMPATIBILITY.
    52 
    53 * "try":
    54   - Added "simp:", "intro:", and "elim:" options.
    55 
    56 * Function package: discontinued option "tailrec".
    57 INCOMPATIBILITY. Use partial_function instead.
    58 
    59 
    60 *** Document preparation ***
    61 
    62 * New term style "isub" as ad-hoc conversion of variables x1, y23 into
    63 subscripted form x\<^isub>1, y\<^isub>2\<^isub>3.
    64 
    65 
    66 *** ML ***
    67 
    68 * Path.print is the official way to show file-system paths to users
    69 (including quotes etc.).
    70 
    71 
    72 
    73 New in Isabelle2011 (January 2011)
    74 ----------------------------------
    75 
    76 *** General ***
    77 
    78 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
    79 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
    80 useful tooltips and hyperlinks produced from its static analysis.  The
    81 bundled component provides an executable Isabelle tool that can be run
    82 like this:
    83 
    84   Isabelle2011/bin/isabelle jedit
    85 
    86 * Significantly improved Isabelle/Isar implementation manual.
    87 
    88 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
    89 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
    90 while the default heap location within that directory lacks that extra
    91 suffix.  This isolates multiple Isabelle installations from each
    92 other, avoiding problems with old settings in new versions.
    93 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
    94 
    95 * Source files are always encoded as UTF-8, instead of old-fashioned
    96 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
    97 the following package declarations:
    98 
    99   \usepackage[utf8]{inputenc}
   100   \usepackage{textcomp}
   101 
   102 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   103 a Unicode character is treated as a single symbol, not a sequence of
   104 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   105 contain symbols without further backslash escapes, Unicode can now be
   106 used here as well.  Recall that Symbol.explode in ML provides a
   107 consistent view on symbols, while raw explode (or String.explode)
   108 merely give a byte-oriented representation.
   109 
   110 * Theory loader: source files are primarily located via the master
   111 directory of each theory node (where the .thy file itself resides).
   112 The global load path is still partially available as legacy feature.
   113 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   114 explicit paths, relatively to the theory.
   115 
   116 * Special treatment of ML file names has been discontinued.
   117 Historically, optional extensions .ML or .sml were added on demand --
   118 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   119 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   120 
   121 * Various options that affect pretty printing etc. are now properly
   122 handled within the context via configuration options, instead of
   123 unsynchronized references or print modes.  There are both ML Config.T
   124 entities and Isar declaration attributes to access these.
   125 
   126   ML (Config.T)                 Isar (attribute)
   127 
   128   eta_contract                  eta_contract
   129   show_brackets                 show_brackets
   130   show_sorts                    show_sorts
   131   show_types                    show_types
   132   show_question_marks           show_question_marks
   133   show_consts                   show_consts
   134   show_abbrevs                  show_abbrevs
   135 
   136   Syntax.ast_trace              syntax_ast_trace
   137   Syntax.ast_stat               syntax_ast_stat
   138   Syntax.ambiguity_level        syntax_ambiguity_level
   139 
   140   Goal_Display.goals_limit      goals_limit
   141   Goal_Display.show_main_goal   show_main_goal
   142 
   143   Method.rule_trace             rule_trace
   144 
   145   Thy_Output.display            thy_output_display
   146   Thy_Output.quotes             thy_output_quotes
   147   Thy_Output.indent             thy_output_indent
   148   Thy_Output.source             thy_output_source
   149   Thy_Output.break              thy_output_break
   150 
   151 Note that corresponding "..._default" references in ML may only be
   152 changed globally at the ROOT session setup, but *not* within a theory.
   153 The option "show_abbrevs" supersedes the former print mode
   154 "no_abbrevs" with inverted meaning.
   155 
   156 * More systematic naming of some configuration options.
   157 INCOMPATIBILITY.
   158 
   159   trace_simp  ~>  simp_trace
   160   debug_simp  ~>  simp_debug
   161 
   162 * Support for real valued configuration options, using simplistic
   163 floating-point notation that coincides with the inner syntax for
   164 float_token.
   165 
   166 * Support for real valued preferences (with approximative PGIP type):
   167 front-ends need to accept "pgint" values in float notation.
   168 INCOMPATIBILITY.
   169 
   170 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   171 DejaVu Sans.
   172 
   173 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   174 
   175 
   176 *** Pure ***
   177 
   178 * Command 'type_synonym' (with single argument) replaces somewhat
   179 outdated 'types', which is still available as legacy feature for some
   180 time.
   181 
   182 * Command 'nonterminal' (with 'and' separated list of arguments)
   183 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   184 
   185 * Command 'notepad' replaces former 'example_proof' for
   186 experimentation in Isar without any result.  INCOMPATIBILITY.
   187 
   188 * Locale interpretation commands 'interpret' and 'sublocale' accept
   189 lists of equations to map definitions in a locale to appropriate
   190 entities in the context of the interpretation.  The 'interpretation'
   191 command already provided this functionality.
   192 
   193 * Diagnostic command 'print_dependencies' prints the locale instances
   194 that would be activated if the specified expression was interpreted in
   195 the current context.  Variant "print_dependencies!" assumes a context
   196 without interpretations.
   197 
   198 * Diagnostic command 'print_interps' prints interpretations in proofs
   199 in addition to interpretations in theories.
   200 
   201 * Discontinued obsolete 'global' and 'local' commands to manipulate
   202 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   203 Sign.root_path and Sign.local_path may be applied directly where this
   204 feature is still required for historical reasons.
   205 
   206 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   207 'definition' instead.
   208 
   209 * The "prems" fact, which refers to the accidental collection of
   210 foundational premises in the context, is now explicitly marked as
   211 legacy feature and will be discontinued soon.  Consider using "assms"
   212 of the head statement or reference facts by explicit names.
   213 
   214 * Document antiquotations @{class} and @{type} print classes and type
   215 constructors.
   216 
   217 * Document antiquotation @{file} checks file/directory entries within
   218 the local file system.
   219 
   220 
   221 *** HOL ***
   222 
   223 * Coercive subtyping: functions can be declared as coercions and type
   224 inference will add them as necessary upon input of a term.  Theory
   225 Complex_Main declares real :: nat => real and real :: int => real as
   226 coercions. A coercion function f is declared like this:
   227 
   228   declare [[coercion f]]
   229 
   230 To lift coercions through type constructors (e.g. from nat => real to
   231 nat list => real list), map functions can be declared, e.g.
   232 
   233   declare [[coercion_map map]]
   234 
   235 Currently coercion inference is activated only in theories including
   236 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   237 the configuration option "coercion_enabled", e.g. it can be enabled in
   238 other theories like this:
   239 
   240   declare [[coercion_enabled]]
   241 
   242 * Command 'partial_function' provides basic support for recursive
   243 function definitions over complete partial orders.  Concrete instances
   244 are provided for i) the option type, ii) tail recursion on arbitrary
   245 types, and iii) the heap monad of Imperative_HOL.  See
   246 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   247 for examples.
   248 
   249 * Function package: f.psimps rules are no longer implicitly declared
   250 as [simp].  INCOMPATIBILITY.
   251 
   252 * Datatype package: theorems generated for executable equality (class
   253 "eq") carry proper names and are treated as default code equations.
   254 
   255 * Inductive package: now offers command 'inductive_simps' to
   256 automatically derive instantiated and simplified equations for
   257 inductive predicates, similar to 'inductive_cases'.
   258 
   259 * Command 'enriched_type' allows to register properties of the
   260 functorial structure of types.
   261 
   262 * Improved infrastructure for term evaluation using code generator
   263 techniques, in particular static evaluation conversions.
   264 
   265 * Code generator: Scala (2.8 or higher) has been added to the target
   266 languages.
   267 
   268 * Code generator: globbing constant expressions "*" and "Theory.*"
   269 have been replaced by the more idiomatic "_" and "Theory._".
   270 INCOMPATIBILITY.
   271 
   272 * Code generator: export_code without explicit file declaration prints
   273 to standard output.  INCOMPATIBILITY.
   274 
   275 * Code generator: do not print function definitions for case
   276 combinators any longer.
   277 
   278 * Code generator: simplification with rules determined with
   279 src/Tools/Code/code_simp.ML and method "code_simp".
   280 
   281 * Code generator for records: more idiomatic representation of record
   282 types.  Warning: records are not covered by ancient SML code
   283 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   284 rep_datatype declaration helps to succeed then:
   285 
   286   record 'a foo = ...
   287   ...
   288   rep_datatype foo_ext ...
   289 
   290 * Records: logical foundation type for records does not carry a
   291 '_type' suffix any longer (obsolete due to authentic syntax).
   292 INCOMPATIBILITY.
   293 
   294 * Quickcheck now by default uses exhaustive testing instead of random
   295 testing.  Random testing can be invoked by "quickcheck [random]",
   296 exhaustive testing by "quickcheck [exhaustive]".
   297 
   298 * Quickcheck instantiates polymorphic types with small finite
   299 datatypes by default. This enables a simple execution mechanism to
   300 handle quantifiers and function equality over the finite datatypes.
   301 
   302 * Quickcheck random generator has been renamed from "code" to
   303 "random".  INCOMPATIBILITY.
   304 
   305 * Quickcheck now has a configurable time limit which is set to 30
   306 seconds by default. This can be changed by adding [timeout = n] to the
   307 quickcheck command. The time limit for Auto Quickcheck is still set
   308 independently.
   309 
   310 * Quickcheck in locales considers interpretations of that locale for
   311 counter example search.
   312 
   313 * Sledgehammer:
   314   - Added "smt" and "remote_smt" provers based on the "smt" proof
   315     method. See the Sledgehammer manual for details ("isabelle doc
   316     sledgehammer").
   317   - Renamed commands:
   318     sledgehammer atp_info ~> sledgehammer running_provers
   319     sledgehammer atp_kill ~> sledgehammer kill_provers
   320     sledgehammer available_atps ~> sledgehammer available_provers
   321     INCOMPATIBILITY.
   322   - Renamed options:
   323     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   324     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   325     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   326     (and "ms" and "min" are no longer supported)
   327     INCOMPATIBILITY.
   328 
   329 * Nitpick:
   330   - Renamed options:
   331     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   332     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   333     INCOMPATIBILITY.
   334   - Added support for partial quotient types.
   335   - Added local versions of the "Nitpick.register_xxx" functions.
   336   - Added "whack" option.
   337   - Allow registration of quotient types as codatatypes.
   338   - Improved "merge_type_vars" option to merge more types.
   339   - Removed unsound "fast_descrs" option.
   340   - Added custom symmetry breaking for datatypes, making it possible to reach
   341     higher cardinalities.
   342   - Prevent the expansion of too large definitions.
   343 
   344 * Proof methods "metis" and "meson" now have configuration options
   345 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   346 to diagnose these tools. E.g.
   347 
   348     using [[metis_trace = true]]
   349 
   350 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   351 manually as command 'solve_direct'.
   352 
   353 * The default SMT solver Z3 must be enabled explicitly (due to
   354 licensing issues) by setting the environment variable
   355 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   356 commercial applications, the SMT solver CVC3 is provided as fall-back;
   357 changing the SMT solver is done via the configuration option
   358 "smt_solver".
   359 
   360 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   361 i.e. "remote_cvc3" and "remote_z3".
   362 
   363 * Added basic SMT support for datatypes, records, and typedefs using
   364 the oracle mode (no proofs).  Direct support of pairs has been dropped
   365 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   366 support for a similar behavior).  Minor INCOMPATIBILITY.
   367 
   368 * Changed SMT configuration options:
   369   - Renamed:
   370     z3_proofs ~> smt_oracle (with inverted meaning)
   371     z3_trace_assms ~> smt_trace_used_facts
   372     INCOMPATIBILITY.
   373   - Added:
   374     smt_verbose
   375     smt_random_seed
   376     smt_datatypes
   377     smt_infer_triggers
   378     smt_monomorph_limit
   379     cvc3_options
   380     remote_cvc3_options
   381     remote_z3_options
   382     yices_options
   383 
   384 * Boogie output files (.b2i files) need to be declared in the theory
   385 header.
   386 
   387 * Simplification procedure "list_to_set_comprehension" rewrites list
   388 comprehensions applied to List.set to set comprehensions.  Occasional
   389 INCOMPATIBILITY, may be deactivated like this:
   390 
   391   declare [[simproc del: list_to_set_comprehension]]
   392 
   393 * Removed old version of primrec package.  INCOMPATIBILITY.
   394 
   395 * Removed simplifier congruence rule of "prod_case", as has for long
   396 been the case with "split".  INCOMPATIBILITY.
   397 
   398 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   399 
   400 * Removed [split_format ... and ... and ...] version of
   401 [split_format].  Potential INCOMPATIBILITY.
   402 
   403 * Predicate "sorted" now defined inductively, with nice induction
   404 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   405 
   406 * Constant "contents" renamed to "the_elem", to free the generic name
   407 contents for other uses.  INCOMPATIBILITY.
   408 
   409 * Renamed class eq and constant eq (for code generation) to class
   410 equal and constant equal, plus renaming of related facts and various
   411 tuning.  INCOMPATIBILITY.
   412 
   413 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   414 
   415 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   416 INCOMPATIBILITY.
   417 
   418 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   419 avoid confusion with finite sets.  INCOMPATIBILITY.
   420 
   421 * Abandoned locales equiv, congruent and congruent2 for equivalence
   422 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   423 for congruent(2)).
   424 
   425 * Some previously unqualified names have been qualified:
   426 
   427   types
   428     bool ~> HOL.bool
   429     nat ~> Nat.nat
   430 
   431   constants
   432     Trueprop ~> HOL.Trueprop
   433     True ~> HOL.True
   434     False ~> HOL.False
   435     op & ~> HOL.conj
   436     op | ~> HOL.disj
   437     op --> ~> HOL.implies
   438     op = ~> HOL.eq
   439     Not ~> HOL.Not
   440     The ~> HOL.The
   441     All ~> HOL.All
   442     Ex ~> HOL.Ex
   443     Ex1 ~> HOL.Ex1
   444     Let ~> HOL.Let
   445     If ~> HOL.If
   446     Ball ~> Set.Ball
   447     Bex ~> Set.Bex
   448     Suc ~> Nat.Suc
   449     Pair ~> Product_Type.Pair
   450     fst ~> Product_Type.fst
   451     snd ~> Product_Type.snd
   452     curry ~> Product_Type.curry
   453     op : ~> Set.member
   454     Collect ~> Set.Collect
   455 
   456 INCOMPATIBILITY.
   457 
   458 * More canonical naming convention for some fundamental definitions:
   459 
   460     bot_bool_eq ~> bot_bool_def
   461     top_bool_eq ~> top_bool_def
   462     inf_bool_eq ~> inf_bool_def
   463     sup_bool_eq ~> sup_bool_def
   464     bot_fun_eq  ~> bot_fun_def
   465     top_fun_eq  ~> top_fun_def
   466     inf_fun_eq  ~> inf_fun_def
   467     sup_fun_eq  ~> sup_fun_def
   468 
   469 INCOMPATIBILITY.
   470 
   471 * More stylized fact names:
   472 
   473   expand_fun_eq ~> fun_eq_iff
   474   expand_set_eq ~> set_eq_iff
   475   set_ext       ~> set_eqI
   476   nat_number    ~> eval_nat_numeral
   477 
   478 INCOMPATIBILITY.
   479 
   480 * Refactoring of code-generation specific operations in theory List:
   481 
   482   constants
   483     null ~> List.null
   484 
   485   facts
   486     mem_iff ~> member_def
   487     null_empty ~> null_def
   488 
   489 INCOMPATIBILITY.  Note that these were not supposed to be used
   490 regularly unless for striking reasons; their main purpose was code
   491 generation.
   492 
   493 Various operations from the Haskell prelude are used for generating
   494 Haskell code.
   495 
   496 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   497 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   498 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   499 
   500 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   501 "*" and "+" respectively.  INCOMPATIBILITY.
   502 
   503 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   504 "Sum_Type.Plus" instead.
   505 
   506 * Constant "split" has been merged with constant "prod_case"; names of
   507 ML functions, facts etc. involving split have been retained so far,
   508 though.  INCOMPATIBILITY.
   509 
   510 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   511 instead.  INCOMPATIBILITY.
   512 
   513 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   514 INCOMPATIBILITY.
   515 
   516 * Former theory Library/Enum is now part of the HOL-Main image.
   517 INCOMPATIBILITY: all constants of the Enum theory now have to be
   518 referred to by its qualified name.
   519 
   520   enum    ~>  Enum.enum
   521   nlists  ~>  Enum.nlists
   522   product ~>  Enum.product
   523 
   524 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   525 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   526 INCOMPATIBILITY.
   527 
   528 * Theory Library/SetsAndFunctions has been split into
   529 Library/Function_Algebras and Library/Set_Algebras; canonical names
   530 for instance definitions for functions; various improvements.
   531 INCOMPATIBILITY.
   532 
   533 * Theory Library/Multiset provides stable quicksort implementation of
   534 sort_key.
   535 
   536 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   537 INCOMPATIBILITY.
   538 
   539 * Session Multivariate_Analysis: introduced a type class for euclidean
   540 space.  Most theorems are now stated in terms of euclidean spaces
   541 instead of finite cartesian products.
   542 
   543   types
   544     real ^ 'n ~>  'a::real_vector
   545               ~>  'a::euclidean_space
   546               ~>  'a::ordered_euclidean_space
   547         (depends on your needs)
   548 
   549   constants
   550      _ $ _        ~> _ $$ _
   551      \<chi> x. _  ~> \<chi>\<chi> x. _
   552      CARD('n)     ~> DIM('a)
   553 
   554 Also note that the indices are now natural numbers and not from some
   555 finite type. Finite cartesian products of euclidean spaces, products
   556 of euclidean spaces the real and complex numbers are instantiated to
   557 be euclidean_spaces.  INCOMPATIBILITY.
   558 
   559 * Session Probability: introduced pextreal as positive extended real
   560 numbers.  Use pextreal as value for measures.  Introduce the
   561 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   562 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   563 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   564 
   565 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   566 INCOMPATIBILITY.
   567 
   568 * Session SPARK (with image HOL-SPARK) provides commands to load and
   569 prove verification conditions generated by the SPARK Ada program
   570 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   571 
   572 
   573 *** HOL-Algebra ***
   574 
   575 * Theorems for additive ring operations (locale abelian_monoid and
   576 descendants) are generated by interpretation from their multiplicative
   577 counterparts.  Names (in particular theorem names) have the mandatory
   578 qualifier 'add'.  Previous theorem names are redeclared for
   579 compatibility.
   580 
   581 * Structure "int_ring" is now an abbreviation (previously a
   582 definition).  This fits more natural with advanced interpretations.
   583 
   584 
   585 *** HOLCF ***
   586 
   587 * The domain package now runs in definitional mode by default: The
   588 former command 'new_domain' is now called 'domain'.  To use the domain
   589 package in its original axiomatic mode, use 'domain (unsafe)'.
   590 INCOMPATIBILITY.
   591 
   592 * The new class "domain" is now the default sort.  Class "predomain"
   593 is an unpointed version of "domain". Theories can be updated by
   594 replacing sort annotations as shown below.  INCOMPATIBILITY.
   595 
   596   'a::type ~> 'a::countable
   597   'a::cpo  ~> 'a::predomain
   598   'a::pcpo ~> 'a::domain
   599 
   600 * The old type class "rep" has been superseded by class "domain".
   601 Accordingly, users of the definitional package must remove any
   602 "default_sort rep" declarations.  INCOMPATIBILITY.
   603 
   604 * The domain package (definitional mode) now supports unpointed
   605 predomain argument types, as long as they are marked 'lazy'. (Strict
   606 arguments must be in class "domain".) For example, the following
   607 domain definition now works:
   608 
   609   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   610 
   611 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   612 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   613 'a option, and 'a list.  Additionally, it configures fixrec and the
   614 domain package to work with these types.  For example:
   615 
   616   fixrec isInl :: "('a + 'b) u -> tr"
   617     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   618 
   619   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   620 
   621 * The "(permissive)" option of fixrec has been replaced with a
   622 per-equation "(unchecked)" option. See
   623 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
   624 
   625 * The "bifinite" class no longer fixes a constant "approx"; the class
   626 now just asserts that such a function exists.  INCOMPATIBILITY.
   627 
   628 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
   629 defines an embedding of type 'a defl into udom by default; instances
   630 of "bifinite" and "domain" classes are available in
   631 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
   632 
   633 * The syntax "REP('a)" has been replaced with "DEFL('a)".
   634 
   635 * The predicate "directed" has been removed.  INCOMPATIBILITY.
   636 
   637 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
   638 
   639 * The function "cprod_map" has been renamed to "prod_map".
   640 INCOMPATIBILITY.
   641 
   642 * The monadic bind operator on each powerdomain has new binder syntax
   643 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
   644 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
   645 
   646 * The infix syntax for binary union on each powerdomain has changed
   647 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
   648 syntax.  INCOMPATIBILITY.
   649 
   650 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
   651 still supported as an input translation.
   652 
   653 * Renamed some theorems (the original names are also still available).
   654 
   655   expand_fun_below   ~> fun_below_iff
   656   below_fun_ext      ~> fun_belowI
   657   expand_cfun_eq     ~> cfun_eq_iff
   658   ext_cfun           ~> cfun_eqI
   659   expand_cfun_below  ~> cfun_below_iff
   660   below_cfun_ext     ~> cfun_belowI
   661   cont2cont_Rep_CFun ~> cont2cont_APP
   662 
   663 * The Abs and Rep functions for various types have changed names.
   664 Related theorem names have also changed to match. INCOMPATIBILITY.
   665 
   666   Rep_CFun  ~> Rep_cfun
   667   Abs_CFun  ~> Abs_cfun
   668   Rep_Sprod ~> Rep_sprod
   669   Abs_Sprod ~> Abs_sprod
   670   Rep_Ssum  ~> Rep_ssum
   671   Abs_Ssum  ~> Abs_ssum
   672 
   673 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   674 been renamed to *_bottom_iff.  INCOMPATIBILITY.
   675 
   676 * Various changes to bisimulation/coinduction with domain package:
   677 
   678   - Definitions of "bisim" constants no longer mention definedness.
   679   - With mutual recursion, "bisim" predicate is now curried.
   680   - With mutual recursion, each type gets a separate coind theorem.
   681   - Variable names in bisim_def and coinduct rules have changed.
   682 
   683 INCOMPATIBILITY.
   684 
   685 * Case combinators generated by the domain package for type "foo" are
   686 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
   687 
   688 * Several theorems have been renamed to more accurately reflect the
   689 names of constants and types involved.  INCOMPATIBILITY.
   690 
   691   thelub_const    ~> lub_const
   692   lub_const       ~> is_lub_const
   693   thelubI         ~> lub_eqI
   694   is_lub_lub      ~> is_lubD2
   695   lubI            ~> is_lub_lub
   696   unique_lub      ~> is_lub_unique
   697   is_ub_lub       ~> is_lub_rangeD1
   698   lub_bin_chain   ~> is_lub_bin_chain
   699   lub_fun         ~> is_lub_fun
   700   thelub_fun      ~> lub_fun
   701   thelub_cfun     ~> lub_cfun
   702   thelub_Pair     ~> lub_Pair
   703   lub_cprod       ~> is_lub_prod
   704   thelub_cprod    ~> lub_prod
   705   minimal_cprod   ~> minimal_prod
   706   inst_cprod_pcpo ~> inst_prod_pcpo
   707   UU_I            ~> bottomI
   708   compact_UU      ~> compact_bottom
   709   deflation_UU    ~> deflation_bottom
   710   finite_deflation_UU ~> finite_deflation_bottom
   711 
   712 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
   713 
   714   sq_ord_less_eq_trans ~> below_eq_trans
   715   sq_ord_eq_less_trans ~> eq_below_trans
   716   refl_less            ~> below_refl
   717   trans_less           ~> below_trans
   718   antisym_less         ~> below_antisym
   719   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
   720   box_less             ~> box_below
   721   rev_trans_less       ~> rev_below_trans
   722   not_less2not_eq      ~> not_below2not_eq
   723   less_UU_iff          ~> below_UU_iff
   724   flat_less_iff        ~> flat_below_iff
   725   adm_less             ~> adm_below
   726   adm_not_less         ~> adm_not_below
   727   adm_compact_not_less ~> adm_compact_not_below
   728   less_fun_def         ~> below_fun_def
   729   expand_fun_less      ~> fun_below_iff
   730   less_fun_ext         ~> fun_belowI
   731   less_discr_def       ~> below_discr_def
   732   discr_less_eq        ~> discr_below_eq
   733   less_unit_def        ~> below_unit_def
   734   less_cprod_def       ~> below_prod_def
   735   prod_lessI           ~> prod_belowI
   736   Pair_less_iff        ~> Pair_below_iff
   737   fst_less_iff         ~> fst_below_iff
   738   snd_less_iff         ~> snd_below_iff
   739   expand_cfun_less     ~> cfun_below_iff
   740   less_cfun_ext        ~> cfun_belowI
   741   injection_less       ~> injection_below
   742   less_up_def          ~> below_up_def
   743   not_Iup_less         ~> not_Iup_below
   744   Iup_less             ~> Iup_below
   745   up_less              ~> up_below
   746   Def_inject_less_eq   ~> Def_below_Def
   747   Def_less_is_eq       ~> Def_below_iff
   748   spair_less_iff       ~> spair_below_iff
   749   less_sprod           ~> below_sprod
   750   spair_less           ~> spair_below
   751   sfst_less_iff        ~> sfst_below_iff
   752   ssnd_less_iff        ~> ssnd_below_iff
   753   fix_least_less       ~> fix_least_below
   754   dist_less_one        ~> dist_below_one
   755   less_ONE             ~> below_ONE
   756   ONE_less_iff         ~> ONE_below_iff
   757   less_sinlD           ~> below_sinlD
   758   less_sinrD           ~> below_sinrD
   759 
   760 
   761 *** FOL and ZF ***
   762 
   763 * All constant names are now qualified internally and use proper
   764 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
   765 
   766 
   767 *** ML ***
   768 
   769 * Antiquotation @{assert} inlines a function bool -> unit that raises
   770 Fail if the argument is false.  Due to inlining the source position of
   771 failed assertions is included in the error output.
   772 
   773 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
   774 text is in practice always evaluated with a stable theory checkpoint.
   775 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
   776 
   777 * Antiquotation @{theory A} refers to theory A from the ancestry of
   778 the current context, not any accidental theory loader state as before.
   779 Potential INCOMPATIBILITY, subtle change in semantics.
   780 
   781 * Syntax.pretty_priority (default 0) configures the required priority
   782 of pretty-printed output and thus affects insertion of parentheses.
   783 
   784 * Syntax.default_root (default "any") configures the inner syntax
   785 category (nonterminal symbol) for parsing of terms.
   786 
   787 * Former exception Library.UnequalLengths now coincides with
   788 ListPair.UnequalLengths.
   789 
   790 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
   791 main functionality is provided by structure Simplifier.
   792 
   793 * Renamed raw "explode" function to "raw_explode" to emphasize its
   794 meaning.  Note that internally to Isabelle, Symbol.explode is used in
   795 almost all situations.
   796 
   797 * Discontinued obsolete function sys_error and exception SYS_ERROR.
   798 See implementation manual for further details on exceptions in
   799 Isabelle/ML.
   800 
   801 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   802 meaning.
   803 
   804 * Renamed structure PureThy to Pure_Thy and moved most of its
   805 operations to structure Global_Theory, to emphasize that this is
   806 rarely-used global-only stuff.
   807 
   808 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
   809 instead (or tracing for high-volume output).
   810 
   811 * Configuration option show_question_marks only affects regular pretty
   812 printing of types and terms, not raw Term.string_of_vname.
   813 
   814 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
   815 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
   816 @{thms} for most purposes.
   817 
   818 * ML structure Unsynchronized is never opened, not even in Isar
   819 interaction mode as before.  Old Unsynchronized.set etc. have been
   820 discontinued -- use plain := instead.  This should be *rare* anyway,
   821 since modern tools always work via official context data, notably
   822 configuration options.
   823 
   824 * Parallel and asynchronous execution requires special care concerning
   825 interrupts.  Structure Exn provides some convenience functions that
   826 avoid working directly with raw Interrupt.  User code must not absorb
   827 interrupts -- intermediate handling (for cleanup etc.) needs to be
   828 followed by re-raising of the original exception.  Another common
   829 source of mistakes are "handle _" patterns, which make the meaning of
   830 the program subject to physical effects of the environment.
   831 
   832 
   833 
   834 New in Isabelle2009-2 (June 2010)
   835 ---------------------------------
   836 
   837 *** General ***
   838 
   839 * Authentic syntax for *all* logical entities (type classes, type
   840 constructors, term constants): provides simple and robust
   841 correspondence between formal entities and concrete syntax.  Within
   842 the parse tree / AST representations, "constants" are decorated by
   843 their category (class, type, const) and spelled out explicitly with
   844 their full internal name.
   845 
   846 Substantial INCOMPATIBILITY concerning low-level syntax declarations
   847 and translations (translation rules and translation functions in ML).
   848 Some hints on upgrading:
   849 
   850   - Many existing uses of 'syntax' and 'translations' can be replaced
   851     by more modern 'type_notation', 'notation' and 'abbreviation',
   852     which are independent of this issue.
   853 
   854   - 'translations' require markup within the AST; the term syntax
   855     provides the following special forms:
   856 
   857       CONST c   -- produces syntax version of constant c from context
   858       XCONST c  -- literally c, checked as constant from context
   859       c         -- literally c, if declared by 'syntax'
   860 
   861     Plain identifiers are treated as AST variables -- occasionally the
   862     system indicates accidental variables via the error "rhs contains
   863     extra variables".
   864 
   865     Type classes and type constructors are marked according to their
   866     concrete syntax.  Some old translations rules need to be written
   867     for the "type" category, using type constructor application
   868     instead of pseudo-term application of the default category
   869     "logic".
   870 
   871   - 'parse_translation' etc. in ML may use the following
   872     antiquotations:
   873 
   874       @{class_syntax c}   -- type class c within parse tree / AST
   875       @{term_syntax c}    -- type constructor c within parse tree / AST
   876       @{const_syntax c}   -- ML version of "CONST c" above
   877       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
   878 
   879   - Literal types within 'typed_print_translations', i.e. those *not*
   880     represented as pseudo-terms are represented verbatim.  Use @{class
   881     c} or @{type_name c} here instead of the above syntax
   882     antiquotations.
   883 
   884 Note that old non-authentic syntax was based on unqualified base
   885 names, so all of the above "constant" names would coincide.  Recall
   886 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
   887 diagnose syntax problems.
   888 
   889 * Type constructors admit general mixfix syntax, not just infix.
   890 
   891 * Concrete syntax may be attached to local entities without a proof
   892 body, too.  This works via regular mixfix annotations for 'fix',
   893 'def', 'obtain' etc. or via the explicit 'write' command, which is
   894 similar to the 'notation' command in theory specifications.
   895 
   896 * Discontinued unnamed infix syntax (legacy feature for many years) --
   897 need to specify constant name and syntax separately.  Internal ML
   898 datatype constructors have been renamed from InfixName to Infix etc.
   899 Minor INCOMPATIBILITY.
   900 
   901 * Schematic theorem statements need to be explicitly markup as such,
   902 via commands 'schematic_lemma', 'schematic_theorem',
   903 'schematic_corollary'.  Thus the relevance of the proof is made
   904 syntactically clear, which impacts performance in a parallel or
   905 asynchronous interactive environment.  Minor INCOMPATIBILITY.
   906 
   907 * Use of cumulative prems via "!" in some proof methods has been
   908 discontinued (old legacy feature).
   909 
   910 * References 'trace_simp' and 'debug_simp' have been replaced by
   911 configuration options stored in the context. Enabling tracing (the
   912 case of debugging is similar) in proofs works via
   913 
   914   using [[trace_simp = true]]
   915 
   916 Tracing is then active for all invocations of the simplifier in
   917 subsequent goal refinement steps. Tracing may also still be enabled or
   918 disabled via the ProofGeneral settings menu.
   919 
   920 * Separate commands 'hide_class', 'hide_type', 'hide_const',
   921 'hide_fact' replace the former 'hide' KIND command.  Minor
   922 INCOMPATIBILITY.
   923 
   924 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
   925 more efficient than combinations with -q1 or -q2.
   926 
   927 
   928 *** Pure ***
   929 
   930 * Proofterms record type-class reasoning explicitly, using the
   931 "unconstrain" operation internally.  This eliminates all sort
   932 constraints from a theorem and proof, introducing explicit
   933 OFCLASS-premises.  On the proof term level, this operation is
   934 automatically applied at theorem boundaries, such that closed proofs
   935 are always free of sort constraints.  INCOMPATIBILITY for tools that
   936 inspect proof terms.
   937 
   938 * Local theory specifications may depend on extra type variables that
   939 are not present in the result type -- arguments TYPE('a) :: 'a itself
   940 are added internally.  For example:
   941 
   942   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
   943 
   944 * Predicates of locales introduced by classes carry a mandatory
   945 "class" prefix.  INCOMPATIBILITY.
   946 
   947 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
   948 
   949 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
   950 'class' instead.
   951 
   952 * Command 'code_reflect' allows to incorporate generated ML code into
   953 runtime environment; replaces immature code_datatype antiquotation.
   954 INCOMPATIBILITY.
   955 
   956 * Code generator: simple concept for abstract datatypes obeying
   957 invariants.
   958 
   959 * Code generator: details of internal data cache have no impact on the
   960 user space functionality any longer.
   961 
   962 * Methods "unfold_locales" and "intro_locales" ignore non-locale
   963 subgoals.  This is more appropriate for interpretations with 'where'.
   964 INCOMPATIBILITY.
   965 
   966 * Command 'example_proof' opens an empty proof body.  This allows to
   967 experiment with Isar, without producing any persistent result.
   968 
   969 * Commands 'type_notation' and 'no_type_notation' declare type syntax
   970 within a local theory context, with explicit checking of the
   971 constructors involved (in contrast to the raw 'syntax' versions).
   972 
   973 * Commands 'types' and 'typedecl' now work within a local theory
   974 context -- without introducing dependencies on parameters or
   975 assumptions, which is not possible in Isabelle/Pure.
   976 
   977 * Command 'defaultsort' has been renamed to 'default_sort', it works
   978 within a local theory context.  Minor INCOMPATIBILITY.
   979 
   980 
   981 *** HOL ***
   982 
   983 * Command 'typedef' now works within a local theory context -- without
   984 introducing dependencies on parameters or assumptions, which is not
   985 possible in Isabelle/Pure/HOL.  Note that the logical environment may
   986 contain multiple interpretations of local typedefs (with different
   987 non-emptiness proofs), even in a global theory context.
   988 
   989 * New package for quotient types.  Commands 'quotient_type' and
   990 'quotient_definition' may be used for defining types and constants by
   991 quotient constructions.  An example is the type of integers created by
   992 quotienting pairs of natural numbers:
   993 
   994   fun
   995     intrel :: "(nat * nat) => (nat * nat) => bool"
   996   where
   997     "intrel (x, y) (u, v) = (x + v = u + y)"
   998 
   999   quotient_type int = "nat * nat" / intrel
  1000     by (auto simp add: equivp_def expand_fun_eq)
  1001 
  1002   quotient_definition
  1003     "0::int" is "(0::nat, 0::nat)"
  1004 
  1005 The method "lifting" can be used to lift of theorems from the
  1006 underlying "raw" type to the quotient type.  The example
  1007 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1008 construction and provides a reasoning infrastructure for finite sets.
  1009 
  1010 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1011 clash with new theory Quotient in Main HOL.
  1012 
  1013 * Moved the SMT binding into the main HOL session, eliminating
  1014 separate HOL-SMT session.
  1015 
  1016 * List membership infix mem operation is only an input abbreviation.
  1017 INCOMPATIBILITY.
  1018 
  1019 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1020 for future developements; former Library/Word.thy is still present in
  1021 the AFP entry RSAPPS.
  1022 
  1023 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1024 longer shadowed.  INCOMPATIBILITY.
  1025 
  1026 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1027 INCOMPATIBILITY.
  1028 
  1029 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1030 INCOMPATIBILITY.
  1031 
  1032 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1033 instead.  INCOMPATIBILITY.
  1034 
  1035 * Dropped several real-specific versions of lemmas about floor and
  1036 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1037 instead.  INCOMPATIBILITY.
  1038 
  1039   floor_number_of_eq         ~> floor_number_of
  1040   le_floor_eq_number_of      ~> number_of_le_floor
  1041   le_floor_eq_zero           ~> zero_le_floor
  1042   le_floor_eq_one            ~> one_le_floor
  1043   floor_less_eq_number_of    ~> floor_less_number_of
  1044   floor_less_eq_zero         ~> floor_less_zero
  1045   floor_less_eq_one          ~> floor_less_one
  1046   less_floor_eq_number_of    ~> number_of_less_floor
  1047   less_floor_eq_zero         ~> zero_less_floor
  1048   less_floor_eq_one          ~> one_less_floor
  1049   floor_le_eq_number_of      ~> floor_le_number_of
  1050   floor_le_eq_zero           ~> floor_le_zero
  1051   floor_le_eq_one            ~> floor_le_one
  1052   floor_subtract_number_of   ~> floor_diff_number_of
  1053   floor_subtract_one         ~> floor_diff_one
  1054   ceiling_number_of_eq       ~> ceiling_number_of
  1055   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1056   ceiling_le_zero_eq         ~> ceiling_le_zero
  1057   ceiling_le_eq_one          ~> ceiling_le_one
  1058   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1059   less_ceiling_eq_zero       ~> zero_less_ceiling
  1060   less_ceiling_eq_one        ~> one_less_ceiling
  1061   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1062   ceiling_less_eq_zero       ~> ceiling_less_zero
  1063   ceiling_less_eq_one        ~> ceiling_less_one
  1064   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1065   le_ceiling_eq_zero         ~> zero_le_ceiling
  1066   le_ceiling_eq_one          ~> one_le_ceiling
  1067   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1068   ceiling_subtract_one       ~> ceiling_diff_one
  1069 
  1070 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1071 application of the various fold combinators on finite sets.
  1072 
  1073 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1074 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1075 implementation.  INCOMPATIBILTY.
  1076 
  1077 * Theory Library/Coinductive_List has been removed -- superseded by
  1078 AFP/thys/Coinductive.
  1079 
  1080 * Theory PReal, including the type "preal" and related operations, has
  1081 been removed.  INCOMPATIBILITY.
  1082 
  1083 * Real: new development using Cauchy Sequences.
  1084 
  1085 * Split off theory "Big_Operators" containing setsum, setprod,
  1086 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1087 
  1088 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1089 "Int" etc.  INCOMPATIBILITY.
  1090 
  1091 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1092 
  1093 * New set of rules "ac_simps" provides combined assoc / commute
  1094 rewrites for all interpretations of the appropriate generic locales.
  1095 
  1096 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1097 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1098 appropriate and more consistent names suitable for name prefixes
  1099 within the HOL theories.  INCOMPATIBILITY.
  1100 
  1101 * Some generic constants have been put to appropriate theories:
  1102   - less_eq, less: Orderings
  1103   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1104   - inverse, divide: Rings
  1105 INCOMPATIBILITY.
  1106 
  1107 * More consistent naming of type classes involving orderings (and
  1108 lattices):
  1109 
  1110     lower_semilattice                   ~> semilattice_inf
  1111     upper_semilattice                   ~> semilattice_sup
  1112 
  1113     dense_linear_order                  ~> dense_linorder
  1114 
  1115     pordered_ab_group_add               ~> ordered_ab_group_add
  1116     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1117     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1118     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1119     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1120     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1121     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1122     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1123     pordered_comm_ring                  ~> ordered_comm_ring
  1124     pordered_comm_semiring              ~> ordered_comm_semiring
  1125     pordered_ring                       ~> ordered_ring
  1126     pordered_ring_abs                   ~> ordered_ring_abs
  1127     pordered_semiring                   ~> ordered_semiring
  1128 
  1129     ordered_ab_group_add                ~> linordered_ab_group_add
  1130     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1131     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1132     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1133     ordered_field                       ~> linordered_field
  1134     ordered_field_no_lb                 ~> linordered_field_no_lb
  1135     ordered_field_no_ub                 ~> linordered_field_no_ub
  1136     ordered_field_dense_linear_order    ~> dense_linordered_field
  1137     ordered_idom                        ~> linordered_idom
  1138     ordered_ring                        ~> linordered_ring
  1139     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1140     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1141     ordered_ring_strict                 ~> linordered_ring_strict
  1142     ordered_semidom                     ~> linordered_semidom
  1143     ordered_semiring                    ~> linordered_semiring
  1144     ordered_semiring_1                  ~> linordered_semiring_1
  1145     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1146     ordered_semiring_strict             ~> linordered_semiring_strict
  1147 
  1148   The following slightly odd type classes have been moved to a
  1149   separate theory Library/Lattice_Algebras:
  1150 
  1151     lordered_ab_group_add               ~> lattice_ab_group_add
  1152     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1153     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1154     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1155     lordered_ring                       ~> lattice_ring
  1156 
  1157 INCOMPATIBILITY.
  1158 
  1159 * Refined field classes:
  1160   - classes division_ring_inverse_zero, field_inverse_zero,
  1161     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1162     subsumes former division_by_zero class;
  1163   - numerous lemmas have been ported from field to division_ring.
  1164 INCOMPATIBILITY.
  1165 
  1166 * Refined algebra theorem collections:
  1167   - dropped theorem group group_simps, use algebra_simps instead;
  1168   - dropped theorem group ring_simps, use field_simps instead;
  1169   - proper theorem collection field_simps subsumes former theorem
  1170     groups field_eq_simps and field_simps;
  1171   - dropped lemma eq_minus_self_iff which is a duplicate for
  1172     equal_neg_zero.
  1173 INCOMPATIBILITY.
  1174 
  1175 * Theory Finite_Set and List: some lemmas have been generalized from
  1176 sets to lattices:
  1177 
  1178   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1179   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1180   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1181   union_Union_fold_union        ~> sup_Sup_fold_sup
  1182   Inter_fold_inter              ~> Inf_fold_inf
  1183   Union_fold_union              ~> Sup_fold_sup
  1184   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1185   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1186   INTER_fold_inter              ~> INFI_fold_inf
  1187   UNION_fold_union              ~> SUPR_fold_sup
  1188 
  1189 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1190 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1191 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1192 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1193 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1194 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1195 
  1196 * Reorganized theory Multiset: swapped notation of pointwise and
  1197 multiset order:
  1198 
  1199   - pointwise ordering is instance of class order with standard syntax
  1200     <= and <;
  1201   - multiset ordering has syntax <=# and <#; partial order properties
  1202     are provided by means of interpretation with prefix
  1203     multiset_order;
  1204   - less duplication, less historical organization of sections,
  1205     conversion from associations lists to multisets, rudimentary code
  1206     generation;
  1207   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1208     if needed.
  1209 
  1210 Renamed:
  1211 
  1212   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1213   multi_count_ext  ~>  multiset_ext
  1214   diff_union_inverse2  ~>  diff_union_cancelR
  1215 
  1216 INCOMPATIBILITY.
  1217 
  1218 * Theory Permutation: replaced local "remove" by List.remove1.
  1219 
  1220 * Code generation: ML and OCaml code is decorated with signatures.
  1221 
  1222 * Theory List: added transpose.
  1223 
  1224 * Library/Nat_Bijection.thy is a collection of bijective functions
  1225 between nat and other types, which supersedes the older libraries
  1226 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1227 
  1228   Constants:
  1229   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1230   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1231   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1232   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1233   Countable.pair_encode           ~> prod_encode
  1234   NatIso.prod2nat                 ~> prod_encode
  1235   NatIso.nat2prod                 ~> prod_decode
  1236   NatIso.sum2nat                  ~> sum_encode
  1237   NatIso.nat2sum                  ~> sum_decode
  1238   NatIso.list2nat                 ~> list_encode
  1239   NatIso.nat2list                 ~> list_decode
  1240   NatIso.set2nat                  ~> set_encode
  1241   NatIso.nat2set                  ~> set_decode
  1242 
  1243   Lemmas:
  1244   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1245   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1246   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1247   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1248   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1249   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1250   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1251   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1252   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1253   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1254   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1255   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1256   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1257 
  1258 * Sledgehammer:
  1259   - Renamed ATP commands:
  1260     atp_info     ~> sledgehammer running_atps
  1261     atp_kill     ~> sledgehammer kill_atps
  1262     atp_messages ~> sledgehammer messages
  1263     atp_minimize ~> sledgehammer minimize
  1264     print_atps   ~> sledgehammer available_atps
  1265     INCOMPATIBILITY.
  1266   - Added user's manual ("isabelle doc sledgehammer").
  1267   - Added option syntax and "sledgehammer_params" to customize
  1268     Sledgehammer's behavior.  See the manual for details.
  1269   - Modified the Isar proof reconstruction code so that it produces
  1270     direct proofs rather than proofs by contradiction.  (This feature
  1271     is still experimental.)
  1272   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1273     full-typed mode.
  1274   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1275 
  1276 * Nitpick:
  1277   - Added and implemented "binary_ints" and "bits" options.
  1278   - Added "std" option and implemented support for nonstandard models.
  1279   - Added and implemented "finitize" option to improve the precision
  1280     of infinite datatypes based on a monotonicity analysis.
  1281   - Added support for quotient types.
  1282   - Added support for "specification" and "ax_specification"
  1283     constructs.
  1284   - Added support for local definitions (for "function" and
  1285     "termination" proofs).
  1286   - Added support for term postprocessors.
  1287   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1288   - Improved efficiency of "destroy_constrs" optimization.
  1289   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1290     record getters.
  1291   - Fixed soundness bug related to higher-order constructors.
  1292   - Fixed soundness bug when "full_descrs" is enabled.
  1293   - Improved precision of set constructs.
  1294   - Added "atoms" option.
  1295   - Added cache to speed up repeated Kodkod invocations on the same
  1296     problems.
  1297   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1298     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1299     "SAT4J_Light".  INCOMPATIBILITY.
  1300   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1301     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1302   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1303 
  1304 * Method "induct" now takes instantiations of the form t, where t is not
  1305   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1306   If this is not intended, t has to be enclosed in parentheses.
  1307   By default, the equalities generated by definitional instantiations
  1308   are pre-simplified, which may cause parameters of inductive cases
  1309   to disappear, or may even delete some of the inductive cases.
  1310   Use "induct (no_simp)" instead of "induct" to restore the old
  1311   behaviour. The (no_simp) option is also understood by the "cases"
  1312   and "nominal_induct" methods, which now perform pre-simplification, too.
  1313   INCOMPATIBILITY.
  1314 
  1315 
  1316 *** HOLCF ***
  1317 
  1318 * Variable names in lemmas generated by the domain package have
  1319 changed; the naming scheme is now consistent with the HOL datatype
  1320 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1321 
  1322 * The domain package no longer defines the function "foo_copy" for
  1323 recursive domain "foo".  The reach lemma is now stated directly in
  1324 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1325 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1326 
  1327 * Most definedness lemmas generated by the domain package (previously
  1328 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1329 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1330 Proofs that used definedness lemmas as intro rules may break,
  1331 potential INCOMPATIBILITY.
  1332 
  1333 * Induction and casedist rules generated by the domain package now
  1334 declare proper case_names (one called "bottom", and one named for each
  1335 constructor).  INCOMPATIBILITY.
  1336 
  1337 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1338 rules are generated for each domain, INCOMPATIBILITY.
  1339 
  1340   foo_bar.reach       ~> foo.reach  bar.reach
  1341   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1342 
  1343 * Some lemmas generated by the domain package have been renamed for
  1344 consistency with the datatype package, INCOMPATIBILITY.
  1345 
  1346   foo.ind        ~> foo.induct
  1347   foo.finite_ind ~> foo.finite_induct
  1348   foo.coind      ~> foo.coinduct
  1349   foo.casedist   ~> foo.exhaust
  1350   foo.exhaust    ~> foo.nchotomy
  1351 
  1352 * For consistency with other definition packages, the fixrec package
  1353 now generates qualified theorem names, INCOMPATIBILITY.
  1354 
  1355   foo_simps  ~> foo.simps
  1356   foo_unfold ~> foo.unfold
  1357   foo_induct ~> foo.induct
  1358 
  1359 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1360 method and internal fixrec proofs now use the default simpset instead.
  1361 INCOMPATIBILITY.
  1362 
  1363 * The "contlub" predicate has been removed.  Proof scripts should use
  1364 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1365 
  1366 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1367 
  1368 * The constants cpair, cfst, and csnd have been removed in favor of
  1369 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1370 
  1371 
  1372 *** ML ***
  1373 
  1374 * Antiquotations for basic formal entities:
  1375 
  1376     @{class NAME}         -- type class
  1377     @{class_syntax NAME}  -- syntax representation of the above
  1378 
  1379     @{type_name NAME}     -- logical type
  1380     @{type_abbrev NAME}   -- type abbreviation
  1381     @{nonterminal NAME}   -- type of concrete syntactic category
  1382     @{type_syntax NAME}   -- syntax representation of any of the above
  1383 
  1384     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1385     @{const_abbrev NAME}  -- abbreviated constant
  1386     @{const_syntax NAME}  -- syntax representation of any of the above
  1387 
  1388 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1389 syntax constant (cf. 'syntax' command).
  1390 
  1391 * Antiquotation @{make_string} inlines a function to print arbitrary
  1392 values similar to the ML toplevel.  The result is compiler dependent
  1393 and may fall back on "?" in certain situations.
  1394 
  1395 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1396 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1397 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1398 not work with the asynchronous Isar document model.
  1399 
  1400 * Configuration options now admit dynamic default values, depending on
  1401 the context or even global references.
  1402 
  1403 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1404 uses an efficient external library if available (for Poly/ML).
  1405 
  1406 * Renamed some important ML structures, while keeping the old names
  1407 for some time as aliases within the structure Legacy:
  1408 
  1409   OuterKeyword  ~>  Keyword
  1410   OuterLex      ~>  Token
  1411   OuterParse    ~>  Parse
  1412   OuterSyntax   ~>  Outer_Syntax
  1413   PrintMode     ~>  Print_Mode
  1414   SpecParse     ~>  Parse_Spec
  1415   ThyInfo       ~>  Thy_Info
  1416   ThyLoad       ~>  Thy_Load
  1417   ThyOutput     ~>  Thy_Output
  1418   TypeInfer     ~>  Type_Infer
  1419 
  1420 Note that "open Legacy" simplifies porting of sources, but forgetting
  1421 to remove it again will complicate porting again in the future.
  1422 
  1423 * Most operations that refer to a global context are named
  1424 accordingly, e.g. Simplifier.global_context or
  1425 ProofContext.init_global.  There are some situations where a global
  1426 context actually works, but under normal circumstances one needs to
  1427 pass the proper local context through the code!
  1428 
  1429 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1430 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1431 Pretty.pp argument to merge, which is absent in the standard
  1432 Theory_Data version.
  1433 
  1434 * Sorts.certify_sort and derived "cert" operations for types and terms
  1435 no longer minimize sorts.  Thus certification at the boundary of the
  1436 inference kernel becomes invariant under addition of class relations,
  1437 which is an important monotonicity principle.  Sorts are now minimized
  1438 in the syntax layer only, at the boundary between the end-user and the
  1439 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1440 explicitly in rare situations.
  1441 
  1442 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1443 emphasize that this is in no way a standard operation.
  1444 INCOMPATIBILITY.
  1445 
  1446 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1447 usual for resolution.  Rare INCOMPATIBILITY.
  1448 
  1449 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1450 to emphasize that these only work in a global situation (which is
  1451 quite rare).
  1452 
  1453 * Curried take and drop in library.ML; negative length is interpreted
  1454 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1455 
  1456 * Proof terms: type substitutions on proof constants now use canonical
  1457 order of type variables.  INCOMPATIBILITY for tools working with proof
  1458 terms.
  1459 
  1460 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1461 may no longer carry premises.  User-level specifications are
  1462 transformed accordingly by Thm.add_axiom/add_def.
  1463 
  1464 
  1465 *** System ***
  1466 
  1467 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1468 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1469 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1470 
  1471 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1472 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1473 respectively.
  1474 
  1475 * Old lib/scripts/polyml-platform is superseded by the
  1476 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1477 variant, even on a 64 bit machine.  The following example setting
  1478 prefers 64 bit if available:
  1479 
  1480   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1481 
  1482 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1483 Isabelle/Scala layer for advanced prover interaction and integration.
  1484 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1485 component.
  1486 
  1487 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1488 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1489 similar to the default assignment of the document preparation system
  1490 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1491 provides some operations for direct access to the font without asking
  1492 the user for manual installation.
  1493 
  1494 
  1495 
  1496 New in Isabelle2009-1 (December 2009)
  1497 -------------------------------------
  1498 
  1499 *** General ***
  1500 
  1501 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1502 one backslash should be used, even in ML sources.
  1503 
  1504 
  1505 *** Pure ***
  1506 
  1507 * Locale interpretation propagates mixins along the locale hierarchy.
  1508 The currently only available mixins are the equations used to map
  1509 local definitions to terms of the target domain of an interpretation.
  1510 
  1511 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1512 loc" to print all interpretations of locale "loc" in the theory.
  1513 Interpretations in proofs are not shown.
  1514 
  1515 * Thoroughly revised locales tutorial.  New section on conditional
  1516 interpretation.
  1517 
  1518 * On instantiation of classes, remaining undefined class parameters
  1519 are formally declared.  INCOMPATIBILITY.
  1520 
  1521 
  1522 *** Document preparation ***
  1523 
  1524 * New generalized style concept for printing terms: @{foo (style) ...}
  1525 instead of @{foo_style style ...}  (old form is still retained for
  1526 backward compatibility).  Styles can be also applied for
  1527 antiquotations prop, term_type and typeof.
  1528 
  1529 
  1530 *** HOL ***
  1531 
  1532 * New proof method "smt" for a combination of first-order logic with
  1533 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1534 fixed-size bitvectors; there is also basic support for higher-order
  1535 features (esp. lambda abstractions).  It is an incomplete decision
  1536 procedure based on external SMT solvers using the oracle mechanism;
  1537 for the SMT solver Z3, this method is proof-producing.  Certificates
  1538 are provided to avoid calling the external solvers solely for
  1539 re-checking proofs.  Due to a remote SMT service there is no need for
  1540 installing SMT solvers locally.  See src/HOL/SMT.
  1541 
  1542 * New commands to load and prove verification conditions generated by
  1543 the Boogie program verifier or derived systems (e.g. the Verifying C
  1544 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1545 
  1546 * New counterexample generator tool 'nitpick' based on the Kodkod
  1547 relational model finder.  See src/HOL/Tools/Nitpick and
  1548 src/HOL/Nitpick_Examples.
  1549 
  1550 * New commands 'code_pred' and 'values' to invoke the predicate
  1551 compiler and to enumerate values of inductive predicates.
  1552 
  1553 * A tabled implementation of the reflexive transitive closure.
  1554 
  1555 * New implementation of quickcheck uses generic code generator;
  1556 default generators are provided for all suitable HOL types, records
  1557 and datatypes.  Old quickcheck can be re-activated importing theory
  1558 Library/SML_Quickcheck.
  1559 
  1560 * New testing tool Mirabelle for automated proof tools.  Applies
  1561 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1562 every proof step in a theory.  To be used in batch mode via the
  1563 "mirabelle" utility.
  1564 
  1565 * New proof method "sos" (sum of squares) for nonlinear real
  1566 arithmetic (originally due to John Harison). It requires theory
  1567 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1568 works well in practice on quantifier-free real arithmetic with +, -,
  1569 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1570 inequalities between polynomials.  It makes use of external
  1571 semidefinite programming solvers.  Method "sos" generates a
  1572 certificate that can be pasted into the proof thus avoiding the need
  1573 to call an external tool every time the proof is checked.  See
  1574 src/HOL/Library/Sum_Of_Squares.
  1575 
  1576 * New method "linarith" invokes existing linear arithmetic decision
  1577 procedure only.
  1578 
  1579 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1580 
  1581 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1582 Causes full type information to be output to the ATPs.  This slows
  1583 ATPs down considerably but eliminates a source of unsound "proofs"
  1584 that fail later.
  1585 
  1586 * New method "metisFT": A version of metis that uses full type
  1587 information in order to avoid failures of proof reconstruction.
  1588 
  1589 * New evaluator "approximate" approximates an real valued term using
  1590 the same method as the approximation method.
  1591 
  1592 * Method "approximate" now supports arithmetic expressions as
  1593 boundaries of intervals and implements interval splitting and Taylor
  1594 series expansion.
  1595 
  1596 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1597 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1598 
  1599 * New theory SupInf of the supremum and infimum operators for sets of
  1600 reals.
  1601 
  1602 * New theory Probability, which contains a development of measure
  1603 theory, eventually leading to Lebesgue integration and probability.
  1604 
  1605 * Extended Multivariate Analysis to include derivation and Brouwer's
  1606 fixpoint theorem.
  1607 
  1608 * Reorganization of number theory, INCOMPATIBILITY:
  1609   - new number theory development for nat and int, in theories Divides
  1610     and GCD as well as in new session Number_Theory
  1611   - some constants and facts now suffixed with _nat and _int
  1612     accordingly
  1613   - former session NumberTheory now named Old_Number_Theory, including
  1614     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1615   - moved theory Pocklington from src/HOL/Library to
  1616     src/HOL/Old_Number_Theory
  1617 
  1618 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1619 lcm of finite and infinite sets. It is shown that they form a complete
  1620 lattice.
  1621 
  1622 * Class semiring_div requires superclass no_zero_divisors and proof of
  1623 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1624 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1625 generalized to class semiring_div, subsuming former theorems
  1626 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1627 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1628 INCOMPATIBILITY.
  1629 
  1630 * Refinements to lattice classes and sets:
  1631   - less default intro/elim rules in locale variant, more default
  1632     intro/elim rules in class variant: more uniformity
  1633   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1634     le_inf_iff
  1635   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1636     sup_aci)
  1637   - renamed ACI to inf_sup_aci
  1638   - new class "boolean_algebra"
  1639   - class "complete_lattice" moved to separate theory
  1640     "Complete_Lattice"; corresponding constants (and abbreviations)
  1641     renamed and with authentic syntax:
  1642     Set.Inf ~>    Complete_Lattice.Inf
  1643     Set.Sup ~>    Complete_Lattice.Sup
  1644     Set.INFI ~>   Complete_Lattice.INFI
  1645     Set.SUPR ~>   Complete_Lattice.SUPR
  1646     Set.Inter ~>  Complete_Lattice.Inter
  1647     Set.Union ~>  Complete_Lattice.Union
  1648     Set.INTER ~>  Complete_Lattice.INTER
  1649     Set.UNION ~>  Complete_Lattice.UNION
  1650   - authentic syntax for
  1651     Set.Pow
  1652     Set.image
  1653   - mere abbreviations:
  1654     Set.empty               (for bot)
  1655     Set.UNIV                (for top)
  1656     Set.inter               (for inf, formerly Set.Int)
  1657     Set.union               (for sup, formerly Set.Un)
  1658     Complete_Lattice.Inter  (for Inf)
  1659     Complete_Lattice.Union  (for Sup)
  1660     Complete_Lattice.INTER  (for INFI)
  1661     Complete_Lattice.UNION  (for SUPR)
  1662   - object-logic definitions as far as appropriate
  1663 
  1664 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1665 Un_subset_iff are explicitly deleted as default simp rules; then also
  1666 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1667 deleted to achieve the desired effect.
  1668 
  1669 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1670 rules by default any longer; the same applies to min_max.inf_absorb1
  1671 etc.  INCOMPATIBILITY.
  1672 
  1673 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1674 pred_set_conv by default.  INCOMPATIBILITY.
  1675 
  1676 * Power operations on relations and functions are now one dedicated
  1677 constant "compow" with infix syntax "^^".  Power operation on
  1678 multiplicative monoids retains syntax "^" and is now defined generic
  1679 in class power.  INCOMPATIBILITY.
  1680 
  1681 * Relation composition "R O S" now has a more standard argument order:
  1682 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1683 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1684 break, since the O_assoc rule was not rewritten like this.  Fix using
  1685 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1686 
  1687 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1688 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1689 INCOMPATIBILITY.
  1690 
  1691 * Most rules produced by inductive and datatype package have mandatory
  1692 prefixes.  INCOMPATIBILITY.
  1693 
  1694 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1695 the attribute of the same name.  Each of the theorems in the list
  1696 DERIV_intros assumes composition with an additional function and
  1697 matches a variable to the derivative, which has to be solved by the
  1698 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1699 of most elementary terms.  Former Maclauren.DERIV_tac and
  1700 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1701 INCOMPATIBILITY.
  1702 
  1703 * Code generator attributes follow the usual underscore convention:
  1704     code_unfold     replaces    code unfold
  1705     code_post       replaces    code post
  1706     etc.
  1707   INCOMPATIBILITY.
  1708 
  1709 * Renamed methods:
  1710     sizechange -> size_change
  1711     induct_scheme -> induction_schema
  1712   INCOMPATIBILITY.
  1713 
  1714 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1715 INCOMPATIBILITY, use "undefined" directly.
  1716 
  1717 * Renamed theorems:
  1718     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1719     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1720     Suc_plus1 -> Suc_eq_plus1
  1721     *anti_sym -> *antisym*
  1722     vector_less_eq_def -> vector_le_def
  1723   INCOMPATIBILITY.
  1724 
  1725 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1726 INCOMPATIBILITY.
  1727 
  1728 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1729 INCOMPATIBILITY.
  1730 
  1731 
  1732 *** HOLCF ***
  1733 
  1734 * Theory Representable defines a class "rep" of domains that are
  1735 representable (via an ep-pair) in the universal domain type "udom".
  1736 Instances are provided for all type constructors defined in HOLCF.
  1737 
  1738 * The 'new_domain' command is a purely definitional version of the
  1739 domain package, for representable domains.  Syntax is identical to the
  1740 old domain package.  The 'new_domain' package also supports indirect
  1741 recursion using previously-defined type constructors.  See
  1742 src/HOLCF/ex/New_Domain.thy for examples.
  1743 
  1744 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1745 on the left-hand side of an equation, and then performs
  1746 simplification.  Rewriting is done using rules declared with the
  1747 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1748 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1749 
  1750 * The pattern-match compiler in 'fixrec' can now handle constructors
  1751 with HOL function types.  Pattern-match combinators for the Pair
  1752 constructor are pre-configured.
  1753 
  1754 * The 'fixrec' package now produces better fixed-point induction rules
  1755 for mutually-recursive definitions:  Induction rules have conclusions
  1756 of the form "P foo bar" instead of "P <foo, bar>".
  1757 
  1758 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1759 been renamed to "below".  The name "below" now replaces "less" in many
  1760 theorem names.  (Legacy theorem names using "less" are still supported
  1761 as well.)
  1762 
  1763 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1764 patterns can be used to generate strictness rules, or to make
  1765 functions more strict (much like the bang-patterns supported by the
  1766 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1767 examples.
  1768 
  1769 
  1770 *** ML ***
  1771 
  1772 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1773 errors and run-time exceptions, including detailed source positions.
  1774 
  1775 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1776 identified entries, with some additional information such as source
  1777 position, logical grouping etc.
  1778 
  1779 * Theory and context data is now introduced by the simplified and
  1780 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1781 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1782 copy operation) is still available for some time.
  1783 
  1784 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1785 provides a high-level programming interface to synchronized state
  1786 variables with atomic update.  This works via pure function
  1787 application within a critical section -- its runtime should be as
  1788 short as possible; beware of deadlocks if critical code is nested,
  1789 either directly or indirectly via other synchronized variables!
  1790 
  1791 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1792 wraps raw ML references, explicitly indicating their non-thread-safe
  1793 behaviour.  The Isar toplevel keeps this structure open, to
  1794 accommodate Proof General as well as quick and dirty interactive
  1795 experiments with references.
  1796 
  1797 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1798 parallel tactical reasoning.
  1799 
  1800 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1801 are similar to SUBPROOF, but are slightly more flexible: only the
  1802 specified parts of the subgoal are imported into the context, and the
  1803 body tactic may introduce new subgoals and schematic variables.
  1804 
  1805 * Old tactical METAHYPS, which does not observe the proof context, has
  1806 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1807 or Subgoal.FOCUS etc.
  1808 
  1809 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1810 functors have their own ML name space there is no point to mark them
  1811 separately.)  Minor INCOMPATIBILITY.
  1812 
  1813 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1814 
  1815 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1816 INCOMPATIBILITY.
  1817 
  1818 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1819 mode, which avoids critical setmp.
  1820 
  1821 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1822 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1823 Attrib/Method.setup introduced in Isabelle2009.
  1824 
  1825 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1826 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1827 last resort.  INCOMPATIBILITY.
  1828 
  1829 * Display.pretty_thm now requires a proper context (cf. former
  1830 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1831 or even Display.pretty_thm_without_context as last resort.
  1832 INCOMPATIBILITY.
  1833 
  1834 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1835 Syntax.pretty_typ/term directly, preferably with proper context
  1836 instead of global theory.
  1837 
  1838 
  1839 *** System ***
  1840 
  1841 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1842 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1843 usedir option -q.
  1844 
  1845 * Support for additional "Isabelle components" via etc/components, see
  1846 also the system manual.
  1847 
  1848 * The isabelle makeall tool now operates on all components with
  1849 IsaMakefile, not just hardwired "logics".
  1850 
  1851 * Removed "compress" option from isabelle-process and isabelle usedir;
  1852 this is always enabled.
  1853 
  1854 * Discontinued support for Poly/ML 4.x versions.
  1855 
  1856 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  1857 on a given logic image.  This requires the lighttpd webserver and is
  1858 currently supported on Linux only.
  1859 
  1860 
  1861 
  1862 New in Isabelle2009 (April 2009)
  1863 --------------------------------
  1864 
  1865 *** General ***
  1866 
  1867 * Simplified main Isabelle executables, with less surprises on
  1868 case-insensitive file-systems (such as Mac OS).
  1869 
  1870   - The main Isabelle tool wrapper is now called "isabelle" instead of
  1871     "isatool."
  1872 
  1873   - The former "isabelle" alias for "isabelle-process" has been
  1874     removed (should rarely occur to regular users).
  1875 
  1876   - The former "isabelle-interface" and its alias "Isabelle" have been
  1877     removed (interfaces are now regular Isabelle tools).
  1878 
  1879 Within scripts and make files, the Isabelle environment variables
  1880 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  1881 respectively.  (The latter are still available as legacy feature.)
  1882 
  1883 The old isabelle-interface wrapper could react in confusing ways if
  1884 the interface was uninstalled or changed otherwise.  Individual
  1885 interface tool configuration is now more explicit, see also the
  1886 Isabelle system manual.  In particular, Proof General is now available
  1887 via "isabelle emacs".
  1888 
  1889 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  1890 purge installed copies of Isabelle executables and re-run "isabelle
  1891 install -p ...", or use symlinks.
  1892 
  1893 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  1894 old ~/isabelle, which was slightly non-standard and apt to cause
  1895 surprises on case-insensitive file-systems (such as Mac OS).
  1896 
  1897 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  1898 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  1899 care is required when using older releases of Isabelle.  Note that
  1900 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  1901 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  1902 
  1903 * Proofs of fully specified statements are run in parallel on
  1904 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  1905 a regular 4-core machine, if the initial heap space is made reasonably
  1906 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  1907 
  1908 * The main reference manuals ("isar-ref", "implementation", and
  1909 "system") have been updated and extended.  Formally checked references
  1910 as hyperlinks are now available uniformly.
  1911 
  1912 
  1913 *** Pure ***
  1914 
  1915 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  1916 respects.  The most important changes are listed below.  See the
  1917 Tutorial on Locales ("locales" manual) for details.
  1918 
  1919 - In locale expressions, instantiation replaces renaming.  Parameters
  1920 must be declared in a for clause.  To aid compatibility with previous
  1921 parameter inheritance, in locale declarations, parameters that are not
  1922 'touched' (instantiation position "_" or omitted) are implicitly added
  1923 with their syntax at the beginning of the for clause.
  1924 
  1925 - Syntax from abbreviations and definitions in locales is available in
  1926 locale expressions and context elements.  The latter is particularly
  1927 useful in locale declarations.
  1928 
  1929 - More flexible mechanisms to qualify names generated by locale
  1930 expressions.  Qualifiers (prefixes) may be specified in locale
  1931 expressions, and can be marked as mandatory (syntax: "name!:") or
  1932 optional (syntax "name?:").  The default depends for plain "name:"
  1933 depends on the situation where a locale expression is used: in
  1934 commands 'locale' and 'sublocale' prefixes are optional, in
  1935 'interpretation' and 'interpret' prefixes are mandatory.  The old
  1936 implicit qualifiers derived from the parameter names of a locale are
  1937 no longer generated.
  1938 
  1939 - Command "sublocale l < e" replaces "interpretation l < e".  The
  1940 instantiation clause in "interpretation" and "interpret" (square
  1941 brackets) is no longer available.  Use locale expressions.
  1942 
  1943 - When converting proof scripts, mandatory qualifiers in
  1944 'interpretation' and 'interpret' should be retained by default, even
  1945 if this is an INCOMPATIBILITY compared to former behavior.  In the
  1946 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  1947 in locale expressions range over a single locale instance only.
  1948 
  1949 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  1950 In existing theorem specifications replace the includes element by the
  1951 respective context elements of the included locale, omitting those
  1952 that are already present in the theorem specification.  Multiple
  1953 assume elements of a locale should be replaced by a single one
  1954 involving the locale predicate.  In the proof body, declarations (most
  1955 notably theorems) may be regained by interpreting the respective
  1956 locales in the proof context as required (command "interpret").
  1957 
  1958 If using "includes" in replacement of a target solely because the
  1959 parameter types in the theorem are not as general as in the target,
  1960 consider declaring a new locale with additional type constraints on
  1961 the parameters (context element "constrains").
  1962 
  1963 - Discontinued "locale (open)".  INCOMPATIBILITY.
  1964 
  1965 - Locale interpretation commands no longer attempt to simplify goal.
  1966 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  1967 methods intro_locales and unfold_locales to clarify.
  1968 
  1969 - Locale interpretation commands no longer accept interpretation
  1970 attributes.  INCOMPATIBILITY.
  1971 
  1972 * Class declaration: so-called "base sort" must not be given in import
  1973 list any longer, but is inferred from the specification.  Particularly
  1974 in HOL, write
  1975 
  1976     class foo = ...
  1977 
  1978 instead of
  1979 
  1980     class foo = type + ...
  1981 
  1982 * Class target: global versions of theorems stemming do not carry a
  1983 parameter prefix any longer.  INCOMPATIBILITY.
  1984 
  1985 * Class 'instance' command no longer accepts attached definitions.
  1986 INCOMPATIBILITY, use proper 'instantiation' target instead.
  1987 
  1988 * Recovered hiding of consts, which was accidentally broken in
  1989 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  1990 makes c inaccessible; consider using ``hide (open) const c'' instead.
  1991 
  1992 * Slightly more coherent Pure syntax, with updated documentation in
  1993 isar-ref manual.  Removed locales meta_term_syntax and
  1994 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  1995 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  1996 directly in regular applications.
  1997 
  1998 * There is a new syntactic category "float_const" for signed decimal
  1999 fractions (e.g. 123.45 or -123.45).
  2000 
  2001 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2002 interface with 'setup' command instead.
  2003 
  2004 * Command 'local_setup' is similar to 'setup', but operates on a local
  2005 theory context.
  2006 
  2007 * The 'axiomatization' command now only works within a global theory
  2008 context.  INCOMPATIBILITY.
  2009 
  2010 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2011 hypotheses.  Sorts required in the course of reasoning need to be
  2012 covered by the constraints in the initial statement, completed by the
  2013 type instance information of the background theory.  Non-trivial sort
  2014 hypotheses, which rarely occur in practice, may be specified via
  2015 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2016 
  2017   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2018 
  2019 The result contains an implicit sort hypotheses as before --
  2020 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2021 normalization.
  2022 
  2023 * Generalized Isar history, with support for linear undo, direct state
  2024 addressing etc.
  2025 
  2026 * Changed defaults for unify configuration options:
  2027 
  2028   unify_trace_bound = 50 (formerly 25)
  2029   unify_search_bound = 60 (formerly 30)
  2030 
  2031 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2032 
  2033   a) On theory merge, the last set of code equations for a particular
  2034      constant is taken (in accordance with the policy applied by other
  2035      parts of the code generator framework).
  2036 
  2037   b) Code equations stemming from explicit declarations (e.g. code
  2038      attribute) gain priority over default code equations stemming
  2039      from definition, primrec, fun etc.
  2040 
  2041 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2042 
  2043 * Unified theorem tables for both code generators.  Thus [code
  2044 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2045 
  2046 * Command 'find_consts' searches for constants based on type and name
  2047 patterns, e.g.
  2048 
  2049     find_consts "_ => bool"
  2050 
  2051 By default, matching is against subtypes, but it may be restricted to
  2052 the whole type.  Searching by name is possible.  Multiple queries are
  2053 conjunctive and queries may be negated by prefixing them with a
  2054 hyphen:
  2055 
  2056     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2057 
  2058 * New 'find_theorems' criterion "solves" matches theorems that
  2059 directly solve the current goal (modulo higher-order unification).
  2060 
  2061 * Auto solve feature for main theorem statements: whenever a new goal
  2062 is stated, "find_theorems solves" is called; any theorems that could
  2063 solve the lemma directly are listed as part of the goal state.
  2064 Cf. associated options in Proof General Isabelle settings menu,
  2065 enabled by default, with reasonable timeout for pathological cases of
  2066 higher-order unification.
  2067 
  2068 
  2069 *** Document preparation ***
  2070 
  2071 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2072 demanding keyword 'by' and supporting the full method expression
  2073 syntax just like the Isar command 'by'.
  2074 
  2075 
  2076 *** HOL ***
  2077 
  2078 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2079 points Main and Complex_Main remain as before.
  2080 
  2081 * Logic image HOL-Plain provides a minimal HOL with the most important
  2082 tools available (inductive, datatype, primrec, ...).  This facilitates
  2083 experimentation and tool development.  Note that user applications
  2084 (and library theories) should never refer to anything below theory
  2085 Main, as before.
  2086 
  2087 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2088 experimentation due to shorter build times.
  2089 
  2090 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2091 were previously part of former HOL-Complex.  Entry point Hyperreal
  2092 remains valid, but theories formerly using Complex_Main should now use
  2093 new entry point Hypercomplex.
  2094 
  2095 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2096 Posix processes.  Avoids potentially expensive forking of the ML
  2097 process.  New thread-based implementation also works on non-Unix
  2098 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2099 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2100 commands are covered in the isar-ref manual.
  2101 
  2102 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2103 sledgehammer without local ATP installation (Vampire etc.). Other
  2104 provers may be included via suitable ML wrappers, see also
  2105 src/HOL/ATP_Linkup.thy.
  2106 
  2107 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2108 menu.
  2109 
  2110 * The metis method no longer fails because the theorem is too trivial
  2111 (contains the empty clause).
  2112 
  2113 * The metis method now fails in the usual manner, rather than raising
  2114 an exception, if it determines that it cannot prove the theorem.
  2115 
  2116 * Method "coherent" implements a prover for coherent logic (see also
  2117 src/Tools/coherent.ML).
  2118 
  2119 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2120 "undefined" is the right choice to replace "arbitrary", though
  2121 logically there is no difference.  INCOMPATIBILITY.
  2122 
  2123 * Command "value" now integrates different evaluation mechanisms.  The
  2124 result of the first successful evaluation mechanism is printed.  In
  2125 square brackets a particular named evaluation mechanisms may be
  2126 specified (currently, [SML], [code] or [nbe]).  See further
  2127 src/HOL/ex/Eval_Examples.thy.
  2128 
  2129 * Normalization by evaluation now allows non-leftlinear equations.
  2130 Declare with attribute [code nbe].
  2131 
  2132 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2133 as the structured Isar versions "cases" and "induct", cf. the
  2134 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2135 are now presented as a list of individual projections
  2136 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2137 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2138 rare situations a different rule is selected --- notably nested tuple
  2139 elimination instead of former prod.exhaust: use explicit (case_tac t
  2140 rule: prod.exhaust) here.
  2141 
  2142 * Attributes "cases", "induct", "coinduct" support "del" option.
  2143 
  2144 * Removed fact "case_split_thm", which duplicates "case_split".
  2145 
  2146 * The option datatype has been moved to a new theory Option.  Renamed
  2147 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2148 
  2149 * New predicate "strict_mono" classifies strict functions on partial
  2150 orders.  With strict functions on linear orders, reasoning about
  2151 (in)equalities is facilitated by theorems "strict_mono_eq",
  2152 "strict_mono_less_eq" and "strict_mono_less".
  2153 
  2154 * Some set operations are now proper qualified constants with
  2155 authentic syntax.  INCOMPATIBILITY:
  2156 
  2157     op Int ~>   Set.Int
  2158     op Un ~>    Set.Un
  2159     INTER ~>    Set.INTER
  2160     UNION ~>    Set.UNION
  2161     Inter ~>    Set.Inter
  2162     Union ~>    Set.Union
  2163     {} ~>       Set.empty
  2164     UNIV ~>     Set.UNIV
  2165 
  2166 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2167 theory Set.
  2168 
  2169 * Auxiliary class "itself" has disappeared -- classes without any
  2170 parameter are treated as expected by the 'class' command.
  2171 
  2172 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2173 
  2174 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2175 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2176 
  2177 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2178 method "approximation".  It proves formulas on real values by using
  2179 interval arithmetic.  In the formulas are also the transcendental
  2180 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2181 allowed. For examples see
  2182 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2183 
  2184 * Theory "Reflection" now resides in HOL/Library.
  2185 
  2186 * Entry point to Word library now simply named "Word".
  2187 INCOMPATIBILITY.
  2188 
  2189 * Made source layout more coherent with logical distribution
  2190 structure:
  2191 
  2192     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2193     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2194     src/HOL/Library/GCD.thy ~> src/HOL/
  2195     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2196     src/HOL/Library/Parity.thy ~> src/HOL/
  2197     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2198     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2199     src/HOL/Real/Lubs.thy ~> src/HOL/
  2200     src/HOL/Real/PReal.thy ~> src/HOL/
  2201     src/HOL/Real/Rational.thy ~> src/HOL/
  2202     src/HOL/Real/RComplete.thy ~> src/HOL/
  2203     src/HOL/Real/RealDef.thy ~> src/HOL/
  2204     src/HOL/Real/RealPow.thy ~> src/HOL/
  2205     src/HOL/Real/Real.thy ~> src/HOL/
  2206     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2207     src/HOL/Complex/Complex.thy ~> src/HOL/
  2208     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2209     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2210     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2211     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2212     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2213     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2214     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2215     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2216     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2217     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2218     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2219     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2220     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2221     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2222     src/HOL/Real/Float ~> src/HOL/Library/
  2223     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2224     src/HOL/Real/RealVector.thy ~> src/HOL/
  2225 
  2226     src/HOL/arith_data.ML ~> src/HOL/Tools
  2227     src/HOL/hologic.ML ~> src/HOL/Tools
  2228     src/HOL/simpdata.ML ~> src/HOL/Tools
  2229     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2230     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2231     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2232     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2233     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2234     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2235     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2236 
  2237     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2238     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2239     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2240     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2241     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2242     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2243 
  2244 * If methods "eval" and "evaluation" encounter a structured proof
  2245 state with !!/==>, only the conclusion is evaluated to True (if
  2246 possible), avoiding strange error messages.
  2247 
  2248 * Method "sizechange" automates termination proofs using (a
  2249 modification of) the size-change principle.  Requires SAT solver.  See
  2250 src/HOL/ex/Termination.thy for examples.
  2251 
  2252 * Simplifier: simproc for let expressions now unfolds if bound
  2253 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2254 
  2255 * Method "arith": Linear arithmetic now ignores all inequalities when
  2256 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2257 
  2258 * New attribute "arith" for facts that should always be used
  2259 automatically by arithmetic. It is intended to be used locally in
  2260 proofs, e.g.
  2261 
  2262   assumes [arith]: "x > 0"
  2263 
  2264 Global usage is discouraged because of possible performance impact.
  2265 
  2266 * New classes "top" and "bot" with corresponding operations "top" and
  2267 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2268 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2269 
  2270 * Changed definition lemma "less_fun_def" in order to provide an
  2271 instance for preorders on functions; use lemma "less_le" instead.
  2272 INCOMPATIBILITY.
  2273 
  2274 * Theory Orderings: class "wellorder" moved here, with explicit
  2275 induction rule "less_induct" as assumption.  For instantiation of
  2276 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2277 INCOMPATIBILITY.
  2278 
  2279 * Theory Orderings: added class "preorder" as superclass of "order".
  2280 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2281 etc. slightly changed.  Some theorems named order_class.* now named
  2282 preorder_class.*.
  2283 
  2284 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2285 "diag" to "Id_on".
  2286 
  2287 * Theory Finite_Set: added a new fold combinator of type
  2288 
  2289   ('a => 'b => 'b) => 'b => 'a set => 'b
  2290 
  2291 Occasionally this is more convenient than the old fold combinator
  2292 which is now defined in terms of the new one and renamed to
  2293 fold_image.
  2294 
  2295 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2296 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2297 extended with further lemmas!).  At the moment both still exist but
  2298 the former will disappear at some point.
  2299 
  2300 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2301 class recpower.  Type-specific simp rules for various recpower types
  2302 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2303 
  2304 rat_power_0    -> power_0
  2305 rat_power_Suc  -> power_Suc
  2306 realpow_0      -> power_0
  2307 realpow_Suc    -> power_Suc
  2308 complexpow_0   -> power_0
  2309 complexpow_Suc -> power_Suc
  2310 power_poly_0   -> power_0
  2311 power_poly_Suc -> power_Suc
  2312 
  2313 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2314 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2315 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2316 of lemmas from Divides has been generalized from nat to class
  2317 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2318 renames resulting from duplicate elimination:
  2319 
  2320     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2321     zero_dvd_iff ~>         dvd_0_left_iff
  2322     dvd_0 ~>                dvd_0_right
  2323     DIVISION_BY_ZERO_DIV ~> div_by_0
  2324     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2325     mult_div ~>             div_mult_self2_is_id
  2326     mult_mod ~>             mod_mult_self2_is_0
  2327 
  2328 * Theory IntDiv: removed many lemmas that are instances of class-based
  2329 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2330 rename old lemmas as follows:
  2331 
  2332 dvd_diff               -> nat_dvd_diff
  2333 dvd_zminus_iff         -> dvd_minus_iff
  2334 mod_add1_eq            -> mod_add_eq
  2335 mod_mult1_eq           -> mod_mult_right_eq
  2336 mod_mult1_eq'          -> mod_mult_left_eq
  2337 mod_mult_distrib_mod   -> mod_mult_eq
  2338 nat_mod_add_left_eq    -> mod_add_left_eq
  2339 nat_mod_add_right_eq   -> mod_add_right_eq
  2340 nat_mod_div_trivial    -> mod_div_trivial
  2341 nat_mod_mod_trivial    -> mod_mod_trivial
  2342 zdiv_zadd_self1        -> div_add_self1
  2343 zdiv_zadd_self2        -> div_add_self2
  2344 zdiv_zmult_self1       -> div_mult_self2_is_id
  2345 zdiv_zmult_self2       -> div_mult_self1_is_id
  2346 zdvd_triv_left         -> dvd_triv_left
  2347 zdvd_triv_right        -> dvd_triv_right
  2348 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2349 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2350 zmod_zadd_left_eq      -> mod_add_left_eq
  2351 zmod_zadd_right_eq     -> mod_add_right_eq
  2352 zmod_zadd_self1        -> mod_add_self1
  2353 zmod_zadd_self2        -> mod_add_self2
  2354 zmod_zadd1_eq          -> mod_add_eq
  2355 zmod_zdiff1_eq         -> mod_diff_eq
  2356 zmod_zdvd_zmod         -> mod_mod_cancel
  2357 zmod_zmod_cancel       -> mod_mod_cancel
  2358 zmod_zmult_self1       -> mod_mult_self2_is_0
  2359 zmod_zmult_self2       -> mod_mult_self1_is_0
  2360 zmod_1                 -> mod_by_1
  2361 zdiv_1                 -> div_by_1
  2362 zdvd_abs1              -> abs_dvd_iff
  2363 zdvd_abs2              -> dvd_abs_iff
  2364 zdvd_refl              -> dvd_refl
  2365 zdvd_trans             -> dvd_trans
  2366 zdvd_zadd              -> dvd_add
  2367 zdvd_zdiff             -> dvd_diff
  2368 zdvd_zminus_iff        -> dvd_minus_iff
  2369 zdvd_zminus2_iff       -> minus_dvd_iff
  2370 zdvd_zmultD            -> dvd_mult_right
  2371 zdvd_zmultD2           -> dvd_mult_left
  2372 zdvd_zmult_mono        -> mult_dvd_mono
  2373 zdvd_0_right           -> dvd_0_right
  2374 zdvd_0_left            -> dvd_0_left_iff
  2375 zdvd_1_left            -> one_dvd
  2376 zminus_dvd_iff         -> minus_dvd_iff
  2377 
  2378 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2379 
  2380 * The real numbers offer decimal input syntax: 12.34 is translated
  2381 into 1234/10^2. This translation is not reversed upon output.
  2382 
  2383 * Theory Library/Polynomial defines an abstract type 'a poly of
  2384 univariate polynomials with coefficients of type 'a.  In addition to
  2385 the standard ring operations, it also supports div and mod.  Code
  2386 generation is also supported, using list-style constructors.
  2387 
  2388 * Theory Library/Inner_Product defines a class of real_inner for real
  2389 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2390 => real.  Class real_inner is a subclass of real_normed_vector from
  2391 theory RealVector.
  2392 
  2393 * Theory Library/Product_Vector provides instances for the product
  2394 type 'a * 'b of several classes from RealVector and Inner_Product.
  2395 Definitions of addition, subtraction, scalar multiplication, norms,
  2396 and inner products are included.
  2397 
  2398 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2399 addition to the field operations, numerals and case syntax are also
  2400 supported.
  2401 
  2402 * Theory Library/Diagonalize provides constructive version of Cantor's
  2403 first diagonalization argument.
  2404 
  2405 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2406 zlcm (for int); carried together from various gcd/lcm developements in
  2407 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2408 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2409 may recover tupled syntax as follows:
  2410 
  2411     hide (open) const gcd
  2412     abbreviation gcd where
  2413       "gcd == (%(a, b). GCD.gcd a b)"
  2414     notation (output)
  2415       GCD.gcd ("gcd '(_, _')")
  2416 
  2417 The same works for lcm, zgcd, zlcm.
  2418 
  2419 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2420 instantiations for algebraic structures.  Removed some duplicate
  2421 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2422 
  2423 * ML antiquotation @{code} takes a constant as argument and generates
  2424 corresponding code in background and inserts name of the corresponding
  2425 resulting ML value/function/datatype constructor binding in place.
  2426 All occurrences of @{code} with a single ML block are generated
  2427 simultaneously.  Provides a generic and safe interface for
  2428 instrumentalizing code generation.  See
  2429 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2430 In future you ought to refrain from ad-hoc compiling generated SML
  2431 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2432 cannot refer to constants for which user-defined serializations are
  2433 set.  Refer to the corresponding ML counterpart directly in that
  2434 cases.
  2435 
  2436 * Command 'rep_datatype': instead of theorem names the command now
  2437 takes a list of terms denoting the constructors of the type to be
  2438 represented as datatype.  The characteristic theorems have to be
  2439 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2440 have disappeared in favour of existing ones:
  2441 
  2442     unit_induct                 ~> unit.induct
  2443     prod_induct                 ~> prod.induct
  2444     sum_induct                  ~> sum.induct
  2445     Suc_Suc_eq                  ~> nat.inject
  2446     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2447 
  2448 
  2449 *** HOL-Algebra ***
  2450 
  2451 * New locales for orders and lattices where the equivalence relation
  2452 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2453 locales use a record structure with field eq for the equivalence.
  2454 
  2455 * New theory of factorial domains.
  2456 
  2457 * Units_l_inv and Units_r_inv are now simp rules by default.
  2458 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2459 and/or r_inv will now also require deletion of these lemmas.
  2460 
  2461 * Renamed the following theorems, INCOMPATIBILITY:
  2462 
  2463 UpperD ~> Upper_memD
  2464 LowerD ~> Lower_memD
  2465 least_carrier ~> least_closed
  2466 greatest_carrier ~> greatest_closed
  2467 greatest_Lower_above ~> greatest_Lower_below
  2468 one_zero ~> carrier_one_zero
  2469 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2470 
  2471 
  2472 *** HOL-Nominal ***
  2473 
  2474 * Nominal datatypes can now contain type-variables.
  2475 
  2476 * Commands 'nominal_inductive' and 'equivariance' work with local
  2477 theory targets.
  2478 
  2479 * Nominal primrec can now works with local theory targets and its
  2480 specification syntax now conforms to the general format as seen in
  2481 'inductive' etc.
  2482 
  2483 * Method "perm_simp" honours the standard simplifier attributes
  2484 (no_asm), (no_asm_use) etc.
  2485 
  2486 * The new predicate #* is defined like freshness, except that on the
  2487 left hand side can be a set or list of atoms.
  2488 
  2489 * Experimental command 'nominal_inductive2' derives strong induction
  2490 principles for inductive definitions.  In contrast to
  2491 'nominal_inductive', which can only deal with a fixed number of
  2492 binders, it can deal with arbitrary expressions standing for sets of
  2493 atoms to be avoided.  The only inductive definition we have at the
  2494 moment that needs this generalisation is the typing rule for Lets in
  2495 the algorithm W:
  2496 
  2497  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2498  -----------------------------------------------------------------
  2499          Gamma |- Let x be t1 in t2 : T2
  2500 
  2501 In this rule one wants to avoid all the binders that are introduced by
  2502 "close Gamma T1".  We are looking for other examples where this
  2503 feature might be useful.  Please let us know.
  2504 
  2505 
  2506 *** HOLCF ***
  2507 
  2508 * Reimplemented the simplification procedure for proving continuity
  2509 subgoals.  The new simproc is extensible; users can declare additional
  2510 continuity introduction rules with the attribute [cont2cont].
  2511 
  2512 * The continuity simproc now uses a different introduction rule for
  2513 solving continuity subgoals on terms with lambda abstractions.  In
  2514 some rare cases the new simproc may fail to solve subgoals that the
  2515 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2516 Potential INCOMPATIBILITY.
  2517 
  2518 * Command 'fixrec': specification syntax now conforms to the general
  2519 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2520 examples.  INCOMPATIBILITY.
  2521 
  2522 
  2523 *** ZF ***
  2524 
  2525 * Proof of Zorn's Lemma for partial orders.
  2526 
  2527 
  2528 *** ML ***
  2529 
  2530 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2531 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2532 depends on multithreading, so timouts will not work before Poly/ML
  2533 5.2.1!
  2534 
  2535 * High-level support for concurrent ML programming, see
  2536 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2537 particularly convenient to organize independent functional
  2538 computations.  The concept of "synchronized variables" provides a
  2539 higher-order interface for components with shared state, avoiding the
  2540 delicate details of mutexes and condition variables.  (Requires
  2541 Poly/ML 5.2.1 or later.)
  2542 
  2543 * ML bindings produced via Isar commands are stored within the Isar
  2544 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2545 become thread-safe and work with undo as expected (concerning
  2546 top-level bindings, not side-effects on global references).
  2547 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2548 compiler at runtime; really global bindings need to be given outside a
  2549 theory.  (Requires Poly/ML 5.2 or later.)
  2550 
  2551 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2552 context.  Top-level ML bindings are stored within the proof context in
  2553 a purely sequential fashion, disregarding the nested proof structure.
  2554 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2555 proof.  (Requires Poly/ML 5.2 or later.)
  2556 
  2557 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2558 and Method.setup, as well as Isar commands 'attribute_setup' and
  2559 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2560 existing code accordingly, or use plain 'setup' together with old
  2561 Method.add_method.
  2562 
  2563 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2564 to 'a -> thm, while results are always tagged with an authentic oracle
  2565 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2566 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2567 accordingly.  Note that extra performance may be gained by producing
  2568 the cterm carefully, avoiding slow Thm.cterm_of.
  2569 
  2570 * Simplified interface for defining document antiquotations via
  2571 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2572 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2573 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2574 examples.
  2575 
  2576 * More systematic treatment of long names, abstract name bindings, and
  2577 name space operations.  Basic operations on qualified names have been
  2578 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2579 Long_Name.append.  Old type bstring has been mostly replaced by
  2580 abstract type binding (see structure Binding), which supports precise
  2581 qualification by packages and local theory targets, as well as proper
  2582 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2583 bstring values into Binding.name, or better pass through abstract
  2584 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2585 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2586 
  2587 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2588 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2589 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2590 
  2591 * Disposed old type and term read functions (Sign.read_def_typ,
  2592 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2593 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2594 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2595 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2596 resort for legacy applications.
  2597 
  2598 * Disposed old declarations, tactics, tactic combinators that refer to
  2599 the simpset or claset of an implicit theory (such as Addsimps,
  2600 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2601 embedded ML text, or local_simpset_of with a proper context passed as
  2602 explicit runtime argument.
  2603 
  2604 * Rules and tactics that read instantiations (read_instantiate,
  2605 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2606 context, which is required for parsing and type-checking.  Moreover,
  2607 the variables are specified as plain indexnames, not string encodings
  2608 thereof.  INCOMPATIBILITY.
  2609 
  2610 * Generic Toplevel.add_hook interface allows to analyze the result of
  2611 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2612 for theorem dependency output of transactions resulting in a new
  2613 theory state.
  2614 
  2615 * ML antiquotations: block-structured compilation context indicated by
  2616 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2617 
  2618   @{binding name}                         - basic name binding
  2619   @{let ?pat = term}                      - term abbreviation (HO matching)
  2620   @{note name = fact}                     - fact abbreviation
  2621   @{thm fact}                             - singleton fact (with attributes)
  2622   @{thms fact}                            - general fact (with attributes)
  2623   @{lemma prop by method}                 - singleton goal
  2624   @{lemma prop by meth1 meth2}            - singleton goal
  2625   @{lemma prop1 ... propN by method}      - general goal
  2626   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2627   @{lemma (open) ...}                     - open derivation
  2628 
  2629 
  2630 *** System ***
  2631 
  2632 * The Isabelle "emacs" tool provides a specific interface to invoke
  2633 Proof General / Emacs, with more explicit failure if that is not
  2634 installed (the old isabelle-interface script silently falls back on
  2635 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2636 installation location of the Proof General distribution.
  2637 
  2638 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2639 the Isabelle process into a JVM/Scala application.  See
  2640 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2641 process wrapper has been discontinued.)
  2642 
  2643 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2644 
  2645 * Various status messages (with exact source position information) are
  2646 emitted, if proper markup print mode is enabled.  This allows
  2647 user-interface components to provide detailed feedback on internal
  2648 prover operations.
  2649 
  2650 
  2651 
  2652 New in Isabelle2008 (June 2008)
  2653 -------------------------------
  2654 
  2655 *** General ***
  2656 
  2657 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2658 and updated, with formally checked references as hyperlinks.
  2659 
  2660 * Theory loader: use_thy (and similar operations) no longer set the
  2661 implicit ML context, which was occasionally hard to predict and in
  2662 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2663 provides a proper context already.
  2664 
  2665 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2666 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2667 'use' within a theory file will do the job.
  2668 
  2669 * Name space merge now observes canonical order, i.e. the second space
  2670 is inserted into the first one, while existing entries in the first
  2671 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2672 swap theory imports.
  2673 
  2674 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2675 INCOMPATIBILITY in identifier syntax etc.
  2676 
  2677 * Outer syntax: string tokens no longer admit escaped white space,
  2678 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2679 white space without escapes.
  2680 
  2681 * Outer syntax: string tokens may contain arbitrary character codes
  2682 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2683 "foo_bar".
  2684 
  2685 
  2686 *** Pure ***
  2687 
  2688 * Context-dependent token translations.  Default setup reverts locally
  2689 fixed variables, and adds hilite markup for undeclared frees.
  2690 
  2691 * Unused theorems can be found using the new command 'unused_thms'.
  2692 There are three ways of invoking it:
  2693 
  2694 (1) unused_thms
  2695      Only finds unused theorems in the current theory.
  2696 
  2697 (2) unused_thms thy_1 ... thy_n -
  2698      Finds unused theorems in the current theory and all of its ancestors,
  2699      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2700 
  2701 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2702      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2703      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2704      their ancestors.
  2705 
  2706 In order to increase the readability of the list produced by
  2707 unused_thms, theorems that have been created by a particular instance
  2708 of a theory command such as 'inductive' or 'function' are considered
  2709 to belong to the same "group", meaning that if at least one theorem in
  2710 this group is used, the other theorems in the same group are no longer
  2711 reported as unused.  Moreover, if all theorems in the group are
  2712 unused, only one theorem in the group is displayed.
  2713 
  2714 Note that proof objects have to be switched on in order for
  2715 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2716 usually the case when using Proof General with the default settings).
  2717 
  2718 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2719 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2720 duplicate fact bindings, or even accidental fact duplications.  Note
  2721 that tools may maintain dynamically scoped facts systematically, using
  2722 PureThy.add_thms_dynamic.
  2723 
  2724 * Command 'hide' now allows to hide from "fact" name space as well.
  2725 
  2726 * Eliminated destructive theorem database, simpset, claset, and
  2727 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2728 update of theories within ML code.
  2729 
  2730 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2731 INCOMPATIBILITY, object-logics depending on former Pure require
  2732 additional setup PureThy.old_appl_syntax_setup; object-logics
  2733 depending on former CPure need to refer to Pure.
  2734 
  2735 * Commands 'use' and 'ML' are now purely functional, operating on
  2736 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2737 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2738 INCOMPATIBILITY.
  2739 
  2740 * Command 'setup': discontinued implicit version with ML reference.
  2741 
  2742 * Instantiation target allows for simultaneous specification of class
  2743 instance operations together with an instantiation proof.
  2744 Type-checking phase allows to refer to class operations uniformly.
  2745 See src/HOL/Complex/Complex.thy for an Isar example and
  2746 src/HOL/Library/Eval.thy for an ML example.
  2747 
  2748 * Indexing of literal facts: be more serious about including only
  2749 facts from the visible specification/proof context, but not the
  2750 background context (locale etc.).  Affects `prop` notation and method
  2751 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2752 situations.
  2753 
  2754 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2755 "(open)" option, which used to expose internal bound variables to the
  2756 proof text.
  2757 
  2758 * Isar statements: removed obsolete case "rule_context".
  2759 INCOMPATIBILITY, better use explicit fixes/assumes.
  2760 
  2761 * Locale proofs: default proof step now includes 'unfold_locales';
  2762 hence 'proof' without argument may be used to unfold locale
  2763 predicates.
  2764 
  2765 
  2766 *** Document preparation ***
  2767 
  2768 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2769 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2770 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2771 spot); renamed link color from "darkblue" to "linkcolor" (default
  2772 value unchanged, can be redefined via \definecolor); no longer sets
  2773 "a4paper" option (unnecessary or even intrusive).
  2774 
  2775 * Antiquotation @{lemma A method} proves proposition A by the given
  2776 method (either a method name or a method name plus (optional) method
  2777 arguments in parentheses) and prints A just like @{prop A}.
  2778 
  2779 
  2780 *** HOL ***
  2781 
  2782 * New primrec package.  Specification syntax conforms in style to
  2783 definition/function/....  No separate induction rule is provided.  The
  2784 "primrec" command distinguishes old-style and new-style specifications
  2785 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2786 When adjusting theories, beware: constants stemming from new-style
  2787 primrec specifications have authentic syntax.
  2788 
  2789 * Metis prover is now an order of magnitude faster, and also works
  2790 with multithreading.
  2791 
  2792 * Metis: the maximum number of clauses that can be produced from a
  2793 theorem is now given by the attribute max_clauses.  Theorems that
  2794 exceed this number are ignored, with a warning printed.
  2795 
  2796 * Sledgehammer no longer produces structured proofs by default. To
  2797 enable, declare [[sledgehammer_full = true]].  Attributes
  2798 reconstruction_modulus, reconstruction_sorts renamed
  2799 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2800 
  2801 * Method "induct_scheme" derives user-specified induction rules
  2802 from well-founded induction and completeness of patterns. This factors
  2803 out some operations that are done internally by the function package
  2804 and makes them available separately.  See
  2805 src/HOL/ex/Induction_Scheme.thy for examples.
  2806 
  2807 * More flexible generation of measure functions for termination
  2808 proofs: Measure functions can be declared by proving a rule of the
  2809 form "is_measure f" and giving it the [measure_function] attribute.
  2810 The "is_measure" predicate is logically meaningless (always true), and
  2811 just guides the heuristic.  To find suitable measure functions, the
  2812 termination prover sets up the goal "is_measure ?f" of the appropriate
  2813 type and generates all solutions by prolog-style backwards proof using
  2814 the declared rules.
  2815 
  2816 This setup also deals with rules like 
  2817 
  2818   "is_measure f ==> is_measure (list_size f)"
  2819 
  2820 which accommodates nested datatypes that recurse through lists.
  2821 Similar rules are predeclared for products and option types.
  2822 
  2823 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2824 
  2825   INCOMPATIBILITIES:
  2826 
  2827   - Definitions of overloaded constants on sets have to be replaced by
  2828     definitions on => and bool.
  2829 
  2830   - Some definitions of overloaded operators on sets can now be proved
  2831     using the definitions of the operators on => and bool.  Therefore,
  2832     the following theorems have been renamed:
  2833 
  2834       subset_def   -> subset_eq
  2835       psubset_def  -> psubset_eq
  2836       set_diff_def -> set_diff_eq
  2837       Compl_def    -> Compl_eq
  2838       Sup_set_def  -> Sup_set_eq
  2839       Inf_set_def  -> Inf_set_eq
  2840       sup_set_def  -> sup_set_eq
  2841       inf_set_def  -> inf_set_eq
  2842 
  2843   - Due to the incompleteness of the HO unification algorithm, some
  2844     rules such as subst may require manual instantiation, if some of
  2845     the unknowns in the rule is a set.
  2846 
  2847   - Higher order unification and forward proofs:
  2848     The proof pattern
  2849 
  2850       have "P (S::'a set)" <...>
  2851       then have "EX S. P S" ..
  2852 
  2853     no longer works (due to the incompleteness of the HO unification
  2854     algorithm) and must be replaced by the pattern
  2855 
  2856       have "EX S. P S"
  2857       proof
  2858         show "P S" <...>
  2859       qed
  2860 
  2861   - Calculational reasoning with subst (or similar rules):
  2862     The proof pattern
  2863 
  2864       have "P (S::'a set)" <...>
  2865       also have "S = T" <...>
  2866       finally have "P T" .
  2867 
  2868     no longer works (for similar reasons as the previous example) and
  2869     must be replaced by something like
  2870 
  2871       have "P (S::'a set)" <...>
  2872       moreover have "S = T" <...>
  2873       ultimately have "P T" by simp
  2874 
  2875   - Tactics or packages written in ML code:
  2876     Code performing pattern matching on types via
  2877 
  2878       Type ("set", [T]) => ...
  2879 
  2880     must be rewritten. Moreover, functions like strip_type or
  2881     binder_types no longer return the right value when applied to a
  2882     type of the form
  2883 
  2884       T1 => ... => Tn => U => bool
  2885 
  2886     rather than
  2887 
  2888       T1 => ... => Tn => U set
  2889 
  2890 * Merged theories Wellfounded_Recursion, Accessible_Part and
  2891 Wellfounded_Relations to theory Wellfounded.
  2892 
  2893 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  2894 
  2895 * Class finite no longer treats UNIV as class parameter.  Use class
  2896 enum from theory Library/Enum instead to achieve a similar effect.
  2897 INCOMPATIBILITY.
  2898 
  2899 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  2900 and "Cons".  INCOMPATIBILITY.
  2901 
  2902 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  2903 Potential INCOMPATIBILITY.
  2904 
  2905 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  2906 injective_fst_snd removed, use split_eta and prod_eqI instead.
  2907 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  2908 
  2909 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  2910 the same name in theory Orderings:
  2911 
  2912   less_trans
  2913   less_linear
  2914   le_imp_less_or_eq
  2915   le_less_trans
  2916   less_le_trans
  2917   less_not_sym
  2918   less_asym
  2919 
  2920 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  2921 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  2922 and different variable names.
  2923 
  2924 * Library/Option_ord.thy: Canonical order on option type.
  2925 
  2926 * Library/RBT.thy: Red-black trees, an efficient implementation of
  2927 finite maps.
  2928 
  2929 * Library/Countable.thy: Type class for countable types.
  2930 
  2931 * Theory Int: The representation of numerals has changed.  The infix
  2932 operator BIT and the bit datatype with constructors B0 and B1 have
  2933 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  2934 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  2935 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  2936 accordingly.
  2937 
  2938 * Theory Nat: definition of <= and < on natural numbers no longer
  2939 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  2940 le_def and less_def have disappeared.  Consider lemmas not_less
  2941 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  2942 
  2943 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  2944 (whose purpose mainly is for various fold_set functionals) have been
  2945 abandoned in favor of the existing algebraic classes
  2946 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  2947 lower_semilattice (resp. upper_semilattice) and linorder.
  2948 INCOMPATIBILITY.
  2949 
  2950 * Theory Transitive_Closure: induct and cases rules now declare proper
  2951 case_names ("base" and "step").  INCOMPATIBILITY.
  2952 
  2953 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  2954 lattices.  The form set-specific version is available as
  2955 Inductive.lfp_ordinal_induct_set.
  2956 
  2957 * Renamed theorems "power.simps" to "power_int.simps".
  2958 INCOMPATIBILITY.
  2959 
  2960 * Class semiring_div provides basic abstract properties of semirings
  2961 with division and modulo operations.  Subsumes former class dvd_mod.
  2962 
  2963 * Merged theories IntDef, Numeral and IntArith into unified theory
  2964 Int.  INCOMPATIBILITY.
  2965 
  2966 * Theory Library/Code_Index: type "index" now represents natural
  2967 numbers rather than integers.  INCOMPATIBILITY.
  2968 
  2969 * New class "uminus" with operation "uminus" (split of from class
  2970 "minus" which now only has operation "minus", binary).
  2971 INCOMPATIBILITY.
  2972 
  2973 * Constants "card", "internal_split", "option_map" now with authentic
  2974 syntax.  INCOMPATIBILITY.
  2975 
  2976 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  2977 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  2978 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  2979 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  2980 Sup_set_def, le_def, less_def, option_map_def now with object
  2981 equality.  INCOMPATIBILITY.
  2982 
  2983 * Records. Removed K_record, and replaced it by pure lambda term
  2984 %x. c. The simplifier setup is now more robust against eta expansion.
  2985 INCOMPATIBILITY: in cases explicitly referring to K_record.
  2986 
  2987 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  2988 
  2989 * Library/ListVector: new theory of arithmetic vector operations.
  2990 
  2991 * Library/Order_Relation: new theory of various orderings as sets of
  2992 pairs.  Defines preorders, partial orders, linear orders and
  2993 well-orders on sets and on types.
  2994 
  2995 
  2996 *** ZF ***
  2997 
  2998 * Renamed some theories to allow to loading both ZF and HOL in the
  2999 same session:
  3000 
  3001   Datatype  -> Datatype_ZF
  3002   Inductive -> Inductive_ZF
  3003   Int       -> Int_ZF
  3004   IntDiv    -> IntDiv_ZF
  3005   Nat       -> Nat_ZF
  3006   List      -> List_ZF
  3007   Main      -> Main_ZF
  3008 
  3009 INCOMPATIBILITY: ZF theories that import individual theories below
  3010 Main might need to be adapted.  Regular theory Main is still
  3011 available, as trivial extension of Main_ZF.
  3012 
  3013 
  3014 *** ML ***
  3015 
  3016 * ML within Isar: antiquotation @{const name} or @{const
  3017 name(typargs)} produces statically-checked Const term.
  3018 
  3019 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3020 (of the same name).  Removed obsolete print command.
  3021 
  3022 * Removed obsolete "use_legacy_bindings" function.
  3023 
  3024 * The ``print mode'' is now a thread-local value derived from a global
  3025 template (the former print_mode reference), thus access becomes
  3026 non-critical.  The global print_mode reference is for session
  3027 management only; user-code should use print_mode_value,
  3028 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3029 
  3030 * Functions system/system_out provide a robust way to invoke external
  3031 shell commands, with propagation of interrupts (requires Poly/ML
  3032 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3033 
  3034 
  3035 *** System ***
  3036 
  3037 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3038 in accordance with Proof General 3.7, which prefers GNU emacs.
  3039 
  3040 * isatool tty runs Isabelle process with plain tty interaction;
  3041 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3042 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3043 
  3044 * isatool browser now works with Cygwin as well, using general
  3045 "javapath" function defined in Isabelle process environment.
  3046 
  3047 * YXML notation provides a simple and efficient alternative to
  3048 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3049 isatool yxml as described in the Isabelle system manual.
  3050 
  3051 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3052 provides general wrapper for managing an Isabelle process in a robust
  3053 fashion, with ``cooked'' output from stdin/stderr.
  3054 
  3055 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3056 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3057 
  3058 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3059 way of changing the user's settings is via
  3060 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3061 script.
  3062 
  3063 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3064 cores of the underlying machine, which is a good starting point for
  3065 optimal performance tuning.  The corresponding usedir option -M allows
  3066 "max" as an alias for "0".  WARNING: does not work on certain versions
  3067 of Mac OS (with Poly/ML 5.1).
  3068 
  3069 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3070 adverse effect of Isabelle flooding interactive front-ends (notably
  3071 ProofGeneral / XEmacs).
  3072 
  3073 
  3074 
  3075 New in Isabelle2007 (November 2007)
  3076 -----------------------------------
  3077 
  3078 *** General ***
  3079 
  3080 * More uniform information about legacy features, notably a
  3081 warning/error of "Legacy feature: ...", depending on the state of the
  3082 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3083 legacy features will disappear eventually.
  3084 
  3085 * Theory syntax: the header format ``theory A = B + C:'' has been
  3086 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3087 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3088 
  3089 * Theory syntax: the old non-Isar theory file format has been
  3090 discontinued altogether.  Note that ML proof scripts may still be used
  3091 with Isar theories; migration is usually quite simple with the ML
  3092 function use_legacy_bindings.  INCOMPATIBILITY.
  3093 
  3094 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3095 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3096 quotes.
  3097 
  3098 * Theory loader: be more serious about observing the static theory
  3099 header specifications (including optional directories), but not the
  3100 accidental file locations of previously successful loads.  The strict
  3101 update policy of former update_thy is now already performed by
  3102 use_thy, so the former has been removed; use_thys updates several
  3103 theories simultaneously, just as 'imports' within a theory header
  3104 specification, but without merging the results.  Potential
  3105 INCOMPATIBILITY: may need to refine theory headers and commands
  3106 ROOT.ML which depend on load order.
  3107 
  3108 * Theory loader: optional support for content-based file
  3109 identification, instead of the traditional scheme of full physical
  3110 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3111 (cf. the system manual).  The new scheme allows to work with
  3112 non-finished theories in persistent session images, such that source
  3113 files may be moved later on without requiring reloads.
  3114 
  3115 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3116 file (with the same base name as the theory) are considered a legacy
  3117 feature, which will disappear eventually. Even now, the theory loader
  3118 no longer maintains dependencies on such files.
  3119 
  3120 * Syntax: the scope for resolving ambiguities via type-inference is
  3121 now limited to individual terms, instead of whole simultaneous
  3122 specifications as before. This greatly reduces the complexity of the
  3123 syntax module and improves flexibility by separating parsing and
  3124 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3125 'fixes' etc.) are required in rare situations.
  3126 
  3127 * Syntax: constants introduced by new-style packages ('definition',
  3128 'abbreviation' etc.) are passed through the syntax module in
  3129 ``authentic mode''. This means that associated mixfix annotations
  3130 really stick to such constants, independently of potential name space
  3131 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3132 trees are represented slightly differently, may need to adapt syntax
  3133 translations accordingly. Use CONST marker in 'translations' and
  3134 @{const_syntax} antiquotation in 'parse_translation' etc.
  3135 
  3136 * Legacy goal package: reduced interface to the bare minimum required
  3137 to keep existing proof scripts running.  Most other user-level
  3138 functions are now part of the OldGoals structure, which is *not* open
  3139 by default (consider isatool expandshort before open OldGoals).
  3140 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3141 these tend to cause confusion about the actual goal (!) context being
  3142 used here, which is not necessarily the same as the_context().
  3143 
  3144 * Command 'find_theorems': supports "*" wild-card in "name:"
  3145 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3146 support a specific search form (see ProofGeneral/CHANGES).
  3147 
  3148 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3149 by default, which means that "prems" (and also "fixed variables") are
  3150 suppressed from proof state output.  Note that the ProofGeneral
  3151 settings mechanism allows to change and save options persistently, but
  3152 older versions of Isabelle will fail to start up if a negative prems
  3153 limit is imposed.
  3154 
  3155 * Local theory targets may be specified by non-nested blocks of
  3156 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3157 contain definitions, theorems etc., including any derived mechanism
  3158 that has been implemented on top of these primitives.  This concept
  3159 generalizes the existing ``theorem (in ...)'' towards more versatility
  3160 and scalability.
  3161 
  3162 * Proof General interface: proper undo of final 'end' command;
  3163 discontinued Isabelle/classic mode (ML proof scripts).
  3164 
  3165 
  3166 *** Document preparation ***
  3167 
  3168 * Added antiquotation @{theory name} which prints the given name,
  3169 after checking that it refers to a valid ancestor theory in the
  3170 current context.
  3171 
  3172 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3173 check the given source text as ML type/structure, printing verbatim.
  3174 
  3175 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3176 "c args == rhs" given in the current context.  (Any number of
  3177 arguments may be given on the LHS.)
  3178 
  3179 
  3180 *** Pure ***
  3181 
  3182 * The 'class' package offers a combination of axclass and locale to
  3183 achieve Haskell-like type classes in Isabelle.  Definitions and
  3184 theorems within a class context produce both relative results (with
  3185 implicit parameters according to the locale context), and polymorphic
  3186 constants with qualified polymorphism (according to the class
  3187 context).  Within the body context of a 'class' target, a separate
  3188 syntax layer ("user space type system") takes care of converting
  3189 between global polymorphic consts and internal locale representation.
  3190 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3191 "isatool doc classes" provides a tutorial.
  3192 
  3193 * Generic code generator framework allows to generate executable
  3194 code for ML and Haskell (including Isabelle classes).  A short usage
  3195 sketch:
  3196 
  3197     internal compilation:
  3198         export_code <list of constants (term syntax)> in SML
  3199     writing SML code to a file:
  3200         export_code <list of constants (term syntax)> in SML <filename>
  3201     writing OCaml code to a file:
  3202         export_code <list of constants (term syntax)> in OCaml <filename>
  3203     writing Haskell code to a bunch of files:
  3204         export_code <list of constants (term syntax)> in Haskell <filename>
  3205 
  3206     evaluating closed propositions to True/False using code generation:
  3207         method ``eval''
  3208 
  3209 Reasonable default setup of framework in HOL.
  3210 
  3211 Theorem attributs for selecting and transforming function equations theorems:
  3212 
  3213     [code fun]:        select a theorem as function equation for a specific constant
  3214     [code fun del]:    deselect a theorem as function equation for a specific constant
  3215     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3216     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3217 
  3218 User-defined serializations (target in {SML, OCaml, Haskell}):
  3219 
  3220     code_const <and-list of constants (term syntax)>
  3221       {(target) <and-list of const target syntax>}+
  3222 
  3223     code_type <and-list of type constructors>
  3224       {(target) <and-list of type target syntax>}+
  3225 
  3226     code_instance <and-list of instances>
  3227       {(target)}+
  3228         where instance ::= <type constructor> :: <class>
  3229 
  3230     code_class <and_list of classes>
  3231       {(target) <and-list of class target syntax>}+
  3232         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3233 
  3234 code_instance and code_class only are effective to target Haskell.
  3235 
  3236 For example usage see src/HOL/ex/Codegenerator.thy and
  3237 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3238 generation from Isabelle/HOL theories is available via "isatool doc
  3239 codegen".
  3240 
  3241 * Code generator: consts in 'consts_code' Isar commands are now
  3242 referred to by usual term syntax (including optional type
  3243 annotations).
  3244 
  3245 * Command 'no_translations' removes translation rules from theory
  3246 syntax.
  3247 
  3248 * Overloaded definitions are now actually checked for acyclic
  3249 dependencies.  The overloading scheme is slightly more general than
  3250 that of Haskell98, although Isabelle does not demand an exact
  3251 correspondence to type class and instance declarations.
  3252 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3253 exotic versions of overloading -- at the discretion of the user!
  3254 
  3255 Polymorphic constants are represented via type arguments, i.e. the
  3256 instantiation that matches an instance against the most general
  3257 declaration given in the signature.  For example, with the declaration
  3258 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3259 as c(nat).  Overloading is essentially simultaneous structural
  3260 recursion over such type arguments.  Incomplete specification patterns
  3261 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3262 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3263 Command 'print_theory' outputs the normalized system of recursive
  3264 equations, see section "definitions".
  3265 
  3266 * Configuration options are maintained within the theory or proof
  3267 context (with name and type bool/int/string), providing a very simple
  3268 interface to a poor-man's version of general context data.  Tools may
  3269 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3270 these values using Config.get etc.  Users may change options via an
  3271 associated attribute of the same name.  This form of context
  3272 declaration works particularly well with commands 'declare' or
  3273 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3274 very easy to avoid global references, which would not observe Isar
  3275 toplevel undo/redo and fail to work with multithreading.
  3276 
  3277 Various global ML references of Pure and HOL have been turned into
  3278 configuration options:
  3279 
  3280   Unify.search_bound		unify_search_bound
  3281   Unify.trace_bound		unify_trace_bound
  3282   Unify.trace_simp		unify_trace_simp
  3283   Unify.trace_types		unify_trace_types
  3284   Simplifier.simp_depth_limit	simp_depth_limit
  3285   Blast.depth_limit		blast_depth_limit
  3286   DatatypeProp.dtK		datatype_distinctness_limit
  3287   fast_arith_neq_limit  	fast_arith_neq_limit
  3288   fast_arith_split_limit	fast_arith_split_limit
  3289 
  3290 * Named collections of theorems may be easily installed as context
  3291 data using the functor NamedThmsFun (see also
  3292 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3293 attributes; there is also a toplevel print command.  This facility is
  3294 just a common case of general context data, which is the preferred way
  3295 for anything more complex than just a list of facts in canonical
  3296 order.
  3297 
  3298 * Isar: command 'declaration' augments a local theory by generic
  3299 declaration functions written in ML.  This enables arbitrary content
  3300 being added to the context, depending on a morphism that tells the
  3301 difference of the original declaration context wrt. the application
  3302 context encountered later on.
  3303 
  3304 * Isar: proper interfaces for simplification procedures.  Command
  3305 'simproc_setup' declares named simprocs (with match patterns, and body
  3306 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3307 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3308 
  3309 * Isar: an extra pair of brackets around attribute declarations
  3310 abbreviates a theorem reference involving an internal dummy fact,
  3311 which will be ignored later --- only the effect of the attribute on
  3312 the background context will persist.  This form of in-place
  3313 declarations is particularly useful with commands like 'declare' and
  3314 'using', for example ``have A using [[simproc a]] by simp''.
  3315 
  3316 * Isar: method "assumption" (and implicit closing of subproofs) now
  3317 takes simple non-atomic goal assumptions into account: after applying
  3318 an assumption as a rule the resulting subgoals are solved by atomic
  3319 assumption steps.  This is particularly useful to finish 'obtain'
  3320 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3321 without referring to the original premise "!!x. P x ==> thesis" in the
  3322 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3323 more permissive.
  3324 
  3325 * Isar: implicit use of prems from the Isar proof context is
  3326 considered a legacy feature.  Common applications like ``have A .''
  3327 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3328 referencing facts explicitly here improves readability and
  3329 maintainability of proof texts.
  3330 
  3331 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3332 the obtained context from the course of reasoning!  For example:
  3333 
  3334   assume "EX x y. A x & B y"   -- "any previous fact"
  3335   then guess x and y by clarify
  3336 
  3337 This technique is potentially adventurous, depending on the facts and
  3338 proof tools being involved here.
  3339 
  3340 * Isar: known facts from the proof context may be specified as literal
  3341 propositions, using ASCII back-quote syntax.  This works wherever
  3342 named facts used to be allowed so far, in proof commands, proof
  3343 methods, attributes etc.  Literal facts are retrieved from the context
  3344 according to unification of type and term parameters.  For example,
  3345 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3346 theorems in the current context, then these are valid literal facts:
  3347 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3348 
  3349 There is also a proof method "fact" which does the same composition
  3350 for explicit goal states, e.g. the following proof texts coincide with
  3351 certain special cases of literal facts:
  3352 
  3353   have "A" by fact                 ==  note `A`
  3354   have "A ==> B" by fact           ==  note `A ==> B`
  3355   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3356   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3357 
  3358 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3359 outer syntax.  Thus symbolic identifiers may be used without
  3360 additional white space in declarations like this: ``assume *: A''.
  3361 
  3362 * Isar: 'print_facts' prints all local facts of the current context,
  3363 both named and unnamed ones.
  3364 
  3365 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3366 
  3367   def x == "t" and y == "u"
  3368 
  3369 * Isar: added command 'unfolding', which is structurally similar to
  3370 'using', but affects both the goal state and facts by unfolding given
  3371 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3372 'unfolded' attribute may be replaced by first-class proof text.
  3373 
  3374 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3375 and command 'unfolding' now all support object-level equalities
  3376 (potentially conditional).  The underlying notion of rewrite rule is
  3377 analogous to the 'rule_format' attribute, but *not* that of the
  3378 Simplifier (which is usually more generous).
  3379 
  3380 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3381 premises of a theorem by n. Useful in conjunction with drule.
  3382 
  3383 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3384 method expression within a sandbox consisting of the first N
  3385 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3386 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3387 simplifies all new goals that emerge from applying rule foo to the
  3388 originally first one.
  3389 
  3390 * Isar: schematic goals are no longer restricted to higher-order
  3391 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3392 expected.
  3393 
  3394 * Isar: the conclusion of a long theorem statement is now either
  3395 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3396 (essentially a disjunction of cases with local parameters and
  3397 assumptions).  The latter allows to express general elimination rules
  3398 adequately; in this notation common elimination rules look like this:
  3399 
  3400   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3401     assumes "EX x. P x"
  3402     obtains x where "P x"
  3403 
  3404   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3405     assumes "A & B"
  3406     obtains A and B
  3407 
  3408   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3409     assumes "A | B"
  3410     obtains
  3411       A
  3412     | B
  3413 
  3414 The subsequent classical rules even refer to the formal "thesis"
  3415 explicitly:
  3416 
  3417   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3418     obtains "~ thesis"
  3419 
  3420   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3421     obtains "thesis ==> something"
  3422 
  3423 The actual proof of an 'obtains' statement is analogous to that of the
  3424 Isar proof element 'obtain', only that there may be several cases.
  3425 Optional case names may be specified in parentheses; these will be
  3426 available both in the present proof and as annotations in the
  3427 resulting rule, for later use with the 'cases' method (cf. attribute
  3428 case_names).
  3429 
  3430 * Isar: the assumptions of a long theorem statement are available as
  3431 "assms" fact in the proof context.  This is more appropriate than the
  3432 (historical) "prems", which refers to all assumptions of the current
  3433 context, including those from the target locale, proof body etc.
  3434 
  3435 * Isar: 'print_statement' prints theorems from the current theory or
  3436 proof context in long statement form, according to the syntax of a
  3437 top-level lemma.
  3438 
  3439 * Isar: 'obtain' takes an optional case name for the local context
  3440 introduction rule (default "that").
  3441 
  3442 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3443 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3444 to occur.
  3445 
  3446 * Pure: syntax "CONST name" produces a fully internalized constant
  3447 according to the current context.  This is particularly useful for
  3448 syntax translations that should refer to internal constant
  3449 representations independently of name spaces.
  3450 
  3451 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3452 instead of "FOO ". This allows multiple binder declarations to coexist
  3453 in the same context.  INCOMPATIBILITY.
  3454 
  3455 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3456 primitive that also works in a locale context (both for constants and
  3457 fixed variables). Type declaration and internal syntactic representation
  3458 of given constants retrieved from the context. Likewise, the
  3459 'no_notation' command allows to remove given syntax annotations from the
  3460 current context.
  3461 
  3462 * Isar/locales: new derived specification elements 'axiomatization',
  3463 'definition', 'abbreviation', which support type-inference, admit
  3464 object-level specifications (equality, equivalence).  See also the
  3465 isar-ref manual.  Examples:
  3466 
  3467   axiomatization
  3468     eq  (infix "===" 50) where
  3469     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3470 
  3471   definition "f x y = x + y + 1"
  3472   definition g where "g x = f x x"
  3473 
  3474   abbreviation
  3475     neq  (infix "=!=" 50) where
  3476     "x =!= y == ~ (x === y)"
  3477 
  3478 These specifications may be also used in a locale context.  Then the
  3479 constants being introduced depend on certain fixed parameters, and the
  3480 constant name is qualified by the locale base name.  An internal
  3481 abbreviation takes care for convenient input and output, making the
  3482 parameters implicit and using the original short name.  See also
  3483 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3484 entities from a monomorphic theory.
  3485 
  3486 Presently, abbreviations are only available 'in' a target locale, but
  3487 not inherited by general import expressions.  Also note that
  3488 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3489 'translations' in common applications.  The "no_abbrevs" print mode
  3490 prevents folding of abbreviations in term output.
  3491 
  3492 Concrete syntax is attached to specified constants in internal form,
  3493 independently of name spaces.  The parse tree representation is
  3494 slightly different -- use 'notation' instead of raw 'syntax', and
  3495 'translations' with explicit "CONST" markup to accommodate this.
  3496 
  3497 * Pure/Isar: unified syntax for new-style specification mechanisms
  3498 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3499 full type inference and dummy patterns ("_").  For example:
  3500 
  3501   definition "K x _ = x"
  3502 
  3503   inductive conj for A B
  3504   where "A ==> B ==> conj A B"
  3505 
  3506 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3507 the current context.  Print mode "no_abbrevs" prevents inversion of
  3508 abbreviations on output.
  3509 
  3510 * Isar/locales: improved parameter handling: use of locales "var" and
  3511 "struct" no longer necessary; - parameter renamings are no longer
  3512 required to be injective.  For example, this allows to define
  3513 endomorphisms as locale endom = homom mult mult h.
  3514 
  3515 * Isar/locales: changed the way locales with predicates are defined.
  3516 Instead of accumulating the specification, the imported expression is
  3517 now an interpretation.  INCOMPATIBILITY: different normal form of
  3518 locale expressions.  In particular, in interpretations of locales with
  3519 predicates, goals repesenting already interpreted fragments are not
  3520 removed automatically.  Use methods `intro_locales' and
  3521 `unfold_locales'; see below.
  3522 
  3523 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3524 provide backward reasoning on locales predicates.  The methods are
  3525 aware of interpretations and discharge corresponding goals.
  3526 `intro_locales' is less aggressive then `unfold_locales' and does not
  3527 unfold predicates to assumptions.
  3528 
  3529 * Isar/locales: the order in which locale fragments are accumulated
  3530 has changed.  This enables to override declarations from fragments due
  3531 to interpretations -- for example, unwanted simp rules.
  3532 
  3533 * Isar/locales: interpretation in theories and proof contexts has been
  3534 extended.  One may now specify (and prove) equations, which are
  3535 unfolded in interpreted theorems.  This is useful for replacing
  3536 defined concepts (constants depending on locale parameters) by
  3537 concepts already existing in the target context.  Example:
  3538 
  3539   interpretation partial_order ["op <= :: [int, int] => bool"]
  3540     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3541 
  3542 Typically, the constant `partial_order.less' is created by a
  3543 definition specification element in the context of locale
  3544 partial_order.
  3545 
  3546 * Method "induct": improved internal context management to support
  3547 local fixes and defines on-the-fly. Thus explicit meta-level
  3548 connectives !!  and ==> are rarely required anymore in inductive goals
  3549 (using object-logic connectives for this purpose has been long
  3550 obsolete anyway). Common proof patterns are explained in
  3551 src/HOL/Induct/Common_Patterns.thy, see also
  3552 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3553 examples.
  3554 
  3555 * Method "induct": improved handling of simultaneous goals. Instead of
  3556 introducing object-level conjunction, the statement is now split into
  3557 several conclusions, while the corresponding symbolic cases are nested
  3558 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3559 see src/HOL/Induct/Common_Patterns.thy, for example.
  3560 
  3561 * Method "induct": mutual induction rules are now specified as a list
  3562 of rule sharing the same induction cases. HOL packages usually provide
  3563 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3564 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3565 mutual induction rules differently, i.e. like this:
  3566 
  3567   (induct rule: foo_bar.inducts)
  3568   (induct set: foo bar)
  3569   (induct pred: foo bar)
  3570   (induct type: foo bar)
  3571 
  3572 The ML function ProjectRule.projections turns old-style rules into the
  3573 new format.
  3574 
  3575 * Method "coinduct": dual of induction, see
  3576 src/HOL/Library/Coinductive_List.thy for various examples.
  3577 
  3578 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3579 considered a legacy feature.
  3580 
  3581 * Attribute "symmetric" produces result with standardized schematic
  3582 variables (index 0).  Potential INCOMPATIBILITY.
  3583 
  3584 * Simplifier: by default the simplifier trace only shows top level
  3585 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3586 default. Thus there is less danger of being flooded by the trace. The
  3587 trace indicates where parts have been suppressed.
  3588   
  3589 * Provers/classical: removed obsolete classical version of elim_format
  3590 attribute; classical elim/dest rules are now treated uniformly when
  3591 manipulating the claset.
  3592 
  3593 * Provers/classical: stricter checks to ensure that supplied intro,
  3594 dest and elim rules are well-formed; dest and elim rules must have at
  3595 least one premise.
  3596 
  3597 * Provers/classical: attributes dest/elim/intro take an optional
  3598 weight argument for the rule (just as the Pure versions).  Weights are
  3599 ignored by automated tools, but determine the search order of single
  3600 rule steps.
  3601 
  3602 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3603 where the body does not mention the bound variable.  Note that dummy
  3604 patterns implicitly depend on their context of bounds, which makes
  3605 "{_. _}" match any set comprehension as expected.  Potential
  3606 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3607 constant "_idtdummy" in the binding position.
  3608 
  3609 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3610 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3611 for example "A -> B" => "Pi A (%_. B)".
  3612 
  3613 * Pure: 'class_deps' command visualizes the subclass relation, using
  3614 the graph browser tool.
  3615 
  3616 * Pure: 'print_theory' now suppresses certain internal declarations by
  3617 default; use '!' option for full details.
  3618 
  3619 
  3620 *** HOL ***
  3621 
  3622 * Method "metis" proves goals by applying the Metis general-purpose
  3623 resolution prover (see also http://gilith.com/software/metis/).
  3624 Examples are in the directory MetisExamples.  WARNING: the
  3625 Isabelle/HOL-Metis integration does not yet work properly with
  3626 multi-threading.
  3627   
  3628 * Command 'sledgehammer' invokes external automatic theorem provers as
  3629 background processes.  It generates calls to the "metis" method if
  3630 successful. These can be pasted into the proof.  Users do not have to
  3631 wait for the automatic provers to return.  WARNING: does not really
  3632 work with multi-threading.
  3633 
  3634 * New "auto_quickcheck" feature tests outermost goal statements for
  3635 potential counter-examples.  Controlled by ML references
  3636 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3637 5000 milliseconds).  Fails silently if statements is outside of
  3638 executable fragment, or any other codgenerator problem occurs.
  3639 
  3640 * New constant "undefined" with axiom "undefined x = undefined".
  3641 
  3642 * Added class "HOL.eq", allowing for code generation with polymorphic
  3643 equality.
  3644 
  3645 * Some renaming of class constants due to canonical name prefixing in
  3646 the new 'class' package:
  3647 
  3648     HOL.abs ~> HOL.abs_class.abs
  3649     HOL.divide ~> HOL.divide_class.divide
  3650     0 ~> HOL.zero_class.zero
  3651     1 ~> HOL.one_class.one
  3652     op + ~> HOL.plus_class.plus
  3653     op - ~> HOL.minus_class.minus
  3654     uminus ~> HOL.minus_class.uminus
  3655     op * ~> HOL.times_class.times
  3656     op < ~> HOL.ord_class.less
  3657     op <= > HOL.ord_class.less_eq
  3658     Nat.power ~> Power.power_class.power
  3659     Nat.size ~> Nat.size_class.size
  3660     Numeral.number_of ~> Numeral.number_class.number_of
  3661     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3662     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3663     Orderings.min ~> Orderings.ord_class.min
  3664     Orderings.max ~> Orderings.ord_class.max
  3665     Divides.op div ~> Divides.div_class.div
  3666     Divides.op mod ~> Divides.div_class.mod
  3667     Divides.op dvd ~> Divides.div_class.dvd
  3668 
  3669 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3670 
  3671 a) User-defined constants using any of the names "plus", "minus",
  3672 "times", "less" or "less_eq". The standard syntax translations for
  3673 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3674 names.
  3675 
  3676 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3677 INCOMPATIBILITY: use more specific names.
  3678 
  3679 c) Permutative equations (e.g. "a + b = b + a")
  3680 Since the change of names also changes the order of terms, permutative
  3681 rewrite rules may get applied in a different order. Experience shows
  3682 that this is rarely the case (only two adaptions in the whole Isabelle
  3683 distribution).  INCOMPATIBILITY: rewrite proofs
  3684 
  3685 d) ML code directly refering to constant names
  3686 This in general only affects hand-written proof tactics, simprocs and
  3687 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3688 Consider using @{const_name} antiquotation.
  3689 
  3690 * New class "default" with associated constant "default".
  3691 
  3692 * Function "sgn" is now overloaded and available on int, real, complex
  3693 (and other numeric types), using class "sgn".  Two possible defs of
  3694 sgn are given as equational assumptions in the classes sgn_if and
  3695 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3696 INCOMPATIBILITY.
  3697 
  3698 * Locale "partial_order" now unified with class "order" (cf. theory
  3699 Orderings), added parameter "less".  INCOMPATIBILITY.
  3700 
  3701 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3702 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3703 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3704 
  3705 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3706 changed order of proof goals in instance proofs.
  3707 
  3708 * The transitivity reasoner for partial and linear orders is set up
  3709 for classes "order" and "linorder".  Instances of the reasoner are available
  3710 in all contexts importing or interpreting the corresponding locales.
  3711 Method "order" invokes the reasoner separately; the reasoner
  3712 is also integrated with the Simplifier as a solver.  Diagnostic
  3713 command 'print_orders' shows the available instances of the reasoner
  3714 in the current context.
  3715 
  3716 * Localized monotonicity predicate in theory "Orderings"; integrated
  3717 lemmas max_of_mono and min_of_mono with this predicate.
  3718 INCOMPATIBILITY.
  3719 
  3720 * Formulation of theorem "dense" changed slightly due to integration
  3721 with new class dense_linear_order.
  3722 
  3723 * Uniform lattice theory development in HOL.
  3724 
  3725     constants "meet" and "join" now named "inf" and "sup"
  3726     constant "Meet" now named "Inf"
  3727 
  3728     classes "meet_semilorder" and "join_semilorder" now named
  3729       "lower_semilattice" and "upper_semilattice"
  3730     class "lorder" now named "lattice"
  3731     class "comp_lat" now named "complete_lattice"
  3732 
  3733     Instantiation of lattice classes allows explicit definitions
  3734     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3735 
  3736   INCOMPATIBILITY.  Theorem renames:
  3737 
  3738     meet_left_le            ~> inf_le1
  3739     meet_right_le           ~> inf_le2
  3740     join_left_le            ~> sup_ge1
  3741     join_right_le           ~> sup_ge2
  3742     meet_join_le            ~> inf_sup_ord
  3743     le_meetI                ~> le_infI
  3744     join_leI                ~> le_supI
  3745     le_meet                 ~> le_inf_iff
  3746     le_join                 ~> ge_sup_conv
  3747     meet_idempotent         ~> inf_idem
  3748     join_idempotent         ~> sup_idem
  3749     meet_comm               ~> inf_commute
  3750     join_comm               ~> sup_commute
  3751     meet_leI1               ~> le_infI1
  3752     meet_leI2               ~> le_infI2
  3753     le_joinI1               ~> le_supI1
  3754     le_joinI2               ~> le_supI2
  3755     meet_assoc              ~> inf_assoc
  3756     join_assoc              ~> sup_assoc
  3757     meet_left_comm          ~> inf_left_commute
  3758     meet_left_idempotent    ~> inf_left_idem
  3759     join_left_comm          ~> sup_left_commute
  3760     join_left_idempotent    ~> sup_left_idem
  3761     meet_aci                ~> inf_aci
  3762     join_aci                ~> sup_aci
  3763     le_def_meet             ~> le_iff_inf
  3764     le_def_join             ~> le_iff_sup
  3765     join_absorp2            ~> sup_absorb2
  3766     join_absorp1            ~> sup_absorb1
  3767     meet_absorp1            ~> inf_absorb1
  3768     meet_absorp2            ~> inf_absorb2
  3769     meet_join_absorp        ~> inf_sup_absorb
  3770     join_meet_absorp        ~> sup_inf_absorb
  3771     distrib_join_le         ~> distrib_sup_le
  3772     distrib_meet_le         ~> distrib_inf_le
  3773 
  3774     add_meet_distrib_left   ~> add_inf_distrib_left
  3775     add_join_distrib_left   ~> add_sup_distrib_left
  3776     is_join_neg_meet        ~> is_join_neg_inf
  3777     is_meet_neg_join        ~> is_meet_neg_sup
  3778     add_meet_distrib_right  ~> add_inf_distrib_right
  3779     add_join_distrib_right  ~> add_sup_distrib_right
  3780     add_meet_join_distribs  ~> add_sup_inf_distribs
  3781     join_eq_neg_meet        ~> sup_eq_neg_inf
  3782     meet_eq_neg_join        ~> inf_eq_neg_sup
  3783     add_eq_meet_join        ~> add_eq_inf_sup
  3784     meet_0_imp_0            ~> inf_0_imp_0
  3785     join_0_imp_0            ~> sup_0_imp_0
  3786     meet_0_eq_0             ~> inf_0_eq_0
  3787     join_0_eq_0             ~> sup_0_eq_0
  3788     neg_meet_eq_join        ~> neg_inf_eq_sup
  3789     neg_join_eq_meet        ~> neg_sup_eq_inf
  3790     join_eq_if              ~> sup_eq_if
  3791 
  3792     mono_meet               ~> mono_inf
  3793     mono_join               ~> mono_sup
  3794     meet_bool_eq            ~> inf_bool_eq
  3795     join_bool_eq            ~> sup_bool_eq
  3796     meet_fun_eq             ~> inf_fun_eq
  3797     join_fun_eq             ~> sup_fun_eq
  3798     meet_set_eq             ~> inf_set_eq
  3799     join_set_eq             ~> sup_set_eq
  3800     meet1_iff               ~> inf1_iff
  3801     meet2_iff               ~> inf2_iff
  3802     meet1I                  ~> inf1I
  3803     meet2I                  ~> inf2I
  3804     meet1D1                 ~> inf1D1
  3805     meet2D1                 ~> inf2D1
  3806     meet1D2                 ~> inf1D2
  3807     meet2D2                 ~> inf2D2
  3808     meet1E                  ~> inf1E
  3809     meet2E                  ~> inf2E
  3810     join1_iff               ~> sup1_iff
  3811     join2_iff               ~> sup2_iff
  3812     join1I1                 ~> sup1I1
  3813     join2I1                 ~> sup2I1
  3814     join1I1                 ~> sup1I1
  3815     join2I2                 ~> sup1I2
  3816     join1CI                 ~> sup1CI
  3817     join2CI                 ~> sup2CI
  3818     join1E                  ~> sup1E
  3819     join2E                  ~> sup2E
  3820 
  3821     is_meet_Meet            ~> is_meet_Inf
  3822     Meet_bool_def           ~> Inf_bool_def
  3823     Meet_fun_def            ~> Inf_fun_def
  3824     Meet_greatest           ~> Inf_greatest
  3825     Meet_lower              ~> Inf_lower
  3826     Meet_set_def            ~> Inf_set_def
  3827 
  3828     Sup_def                 ~> Sup_Inf
  3829     Sup_bool_eq             ~> Sup_bool_def
  3830     Sup_fun_eq              ~> Sup_fun_def
  3831     Sup_set_eq              ~> Sup_set_def
  3832 
  3833     listsp_meetI            ~> listsp_infI
  3834     listsp_meet_eq          ~> listsp_inf_eq
  3835 
  3836     meet_min                ~> inf_min
  3837     join_max                ~> sup_max
  3838 
  3839 * Added syntactic class "size"; overloaded constant "size" now has
  3840 type "'a::size ==> bool"
  3841 
  3842 * Internal reorganisation of `size' of datatypes: size theorems
  3843 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3844 simplification rules by default!); theorems "prod.size" now named
  3845 "*.size".
  3846 
  3847 * Class "div" now inherits from class "times" rather than "type".
  3848 INCOMPATIBILITY.
  3849 
  3850 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  3851 Linorder etc.  have disappeared; operations defined in terms of
  3852 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  3853 
  3854 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  3855 
  3856 * HOL-Word: New extensive library and type for generic, fixed size
  3857 machine words, with arithemtic, bit-wise, shifting and rotating
  3858 operations, reflection into int, nat, and bool lists, automation for
  3859 linear arithmetic (by automatic reflection into nat or int), including
  3860 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  3861 arithmetic type classes, supporting automatic simplification of
  3862 numerals on all operations.
  3863 
  3864 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  3865 
  3866 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  3867 
  3868 * Code generator library theories:
  3869   - Code_Integer represents HOL integers by big integer literals in target
  3870     languages.
  3871   - Code_Char represents HOL characters by character literals in target
  3872     languages.
  3873   - Code_Char_chr like Code_Char, but also offers treatment of character
  3874     codes; includes Code_Integer.
  3875   - Executable_Set allows to generate code for finite sets using lists.
  3876   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  3877     denominator).
  3878   - Executable_Real implements a subset of real numbers, namly those
  3879     representable by rational numbers.
  3880   - Efficient_Nat implements natural numbers by integers, which in general will
  3881     result in higher efficency; pattern matching with 0/Suc is eliminated;
  3882     includes Code_Integer.
  3883   - Code_Index provides an additional datatype index which is mapped to
  3884     target-language built-in integers.
  3885   - Code_Message provides an additional datatype message_string which is isomorphic to
  3886     strings; messages are mapped to target-language strings.
  3887 
  3888 * New package for inductive predicates
  3889 
  3890   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  3891 
  3892     inductive
  3893       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3894       for z_1 :: U_1 and ... and z_n :: U_m
  3895     where
  3896       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3897     | ...
  3898 
  3899   with full support for type-inference, rather than
  3900 
  3901     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3902 
  3903     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3904     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3905 
  3906     inductive "s z_1 ... z_m"
  3907     intros
  3908       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3909       ...
  3910 
  3911   For backward compatibility, there is a wrapper allowing inductive
  3912   sets to be defined with the new package via
  3913 
  3914     inductive_set
  3915       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3916       for z_1 :: U_1 and ... and z_n :: U_m
  3917     where
  3918       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3919     | ...
  3920 
  3921   or
  3922 
  3923     inductive_set
  3924       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3925       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3926       for z_1 :: U_1 and ... and z_n :: U_m
  3927     where
  3928       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3929     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3930     | ...
  3931 
  3932   if the additional syntax "p ..." is required.
  3933 
  3934   Numerous examples can be found in the subdirectories src/HOL/Auth,
  3935   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  3936 
  3937   INCOMPATIBILITIES:
  3938 
  3939   - Since declaration and definition of inductive sets or predicates
  3940     is no longer separated, abbreviations involving the newly
  3941     introduced sets or predicates must be specified together with the
  3942     introduction rules after the 'where' keyword (see above), rather
  3943     than before the actual inductive definition.
  3944 
  3945   - The variables in induction and elimination rules are now
  3946     quantified in the order of their occurrence in the introduction
  3947     rules, rather than in alphabetical order. Since this may break
  3948     some proofs, these proofs either have to be repaired, e.g. by
  3949     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  3950     statements of the form
  3951 
  3952       case (rule_i a_i_1 ... a_i_{k_i})
  3953 
  3954     or the old order of quantification has to be restored by explicitly adding
  3955     meta-level quantifiers in the introduction rules, i.e.
  3956 
  3957       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  3958 
  3959   - The format of the elimination rules is now
  3960 
  3961       p z_1 ... z_m x_1 ... x_n ==>
  3962         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3963         ==> ... ==> P
  3964 
  3965     for predicates and
  3966 
  3967       (x_1, ..., x_n) : s z_1 ... z_m ==>
  3968         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3969         ==> ... ==> P
  3970 
  3971     for sets rather than
  3972 
  3973       x : s z_1 ... z_m ==>
  3974         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  3975         ==> ... ==> P
  3976 
  3977     This may require terms in goals to be expanded to n-tuples
  3978     (e.g. using case_tac or simplification with the split_paired_all
  3979     rule) before the above elimination rule is applicable.
  3980 
  3981   - The elimination or case analysis rules for (mutually) inductive
  3982     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  3983     list of rules "p_1_..._p_k.elims" is no longer available.
  3984 
  3985 * New package "function"/"fun" for general recursive functions,
  3986 supporting mutual and nested recursion, definitions in local contexts,
  3987 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  3988 for small examples, and the separate tutorial on the function
  3989 package. The old recdef "package" is still available as before, but
  3990 users are encouraged to use the new package.
  3991 
  3992 * Method "lexicographic_order" automatically synthesizes termination
  3993 relations as lexicographic combinations of size measures. 
  3994 
  3995 * Case-expressions allow arbitrary constructor-patterns (including
  3996 "_") and take their order into account, like in functional
  3997 programming.  Internally, this is translated into nested
  3998 case-expressions; missing cases are added and mapped to the predefined
  3999 constant "undefined". In complicated cases printing may no longer show
  4000 the original input but the internal form. Lambda-abstractions allow
  4001 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4002 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4003 variable.
  4004 
  4005 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4006 is an abbreviation for "of_nat :: nat => int". The simplification
  4007 rules for "of_nat" have been changed to work like "int" did
  4008 previously.  Potential INCOMPATIBILITY:
  4009   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4010   - of_nat_diff and of_nat_mult are no longer default simp rules
  4011 
  4012 * Method "algebra" solves polynomial equations over (semi)rings using
  4013 Groebner bases. The (semi)ring structure is defined by locales and the
  4014 tool setup depends on that generic context. Installing the method for
  4015 a specific type involves instantiating the locale and possibly adding
  4016 declarations for computation on the coefficients.  The method is
  4017 already instantiated for natural numbers and for the axiomatic class
  4018 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4019 CALCULEMUS 2007 for the general principles underlying this
  4020 architecture of context-aware proof-tools.
  4021 
  4022 * Method "ferrack" implements quantifier elimination over
  4023 special-purpose dense linear orders using locales (analogous to
  4024 "algebra"). The method is already installed for class
  4025 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4026 rat, etc.
  4027 
  4028 * Former constant "List.op @" now named "List.append".  Use ML
  4029 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4030 circumvent possible incompatibilities when working on ML level.
  4031 
  4032 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4033 
  4034 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4035 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4036 
  4037 * New syntax for Haskell-like list comprehension (input only), eg.
  4038 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4039 
  4040 * The special syntax for function "filter" has changed from [x :
  4041 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4042 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4043 
  4044 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4045 defined on nat only, as an abbreviation for [a..<Suc b]
  4046 INCOMPATIBILITY.
  4047 
  4048 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4049 
  4050 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4051 
  4052 * New lemma collection field_simps (an extension of ring_simps) for
  4053 manipulating (in)equations involving division. Multiplies with all
  4054 denominators that can be proved to be non-zero (in equations) or
  4055 positive/negative (in inequations).
  4056 
  4057 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4058 have been improved and renamed to ring_simps, group_simps and
  4059 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4060 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4061 
  4062 * Theory Library/Commutative_Ring: switched from recdef to function
  4063 package; constants add, mul, pow now curried.  Infix syntax for
  4064 algebraic operations.
  4065 
  4066 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4067 INCOMPATIBILITY.
  4068 
  4069 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4070 INCOMPATIBILITY.
  4071 
  4072 * HOL/records: generalised field-update to take a function on the
  4073 field rather than the new value: r(|A := x|) is translated to A_update
  4074 (K x) r The K-combinator that is internally used is called K_record.
  4075 INCOMPATIBILITY: Usage of the plain update functions has to be
  4076 adapted.
  4077  
  4078 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4079 * x = 0, which are required for a semiring.  Richer structures do not
  4080 inherit from semiring_0 anymore, because this property is a theorem
  4081 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4082 there is more to prove, but this is mostly trivial.
  4083 
  4084 * Class "recpower" is generalized to arbitrary monoids, not just
  4085 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4086 commutativity or semiring properties additionally.
  4087 
  4088 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4089 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4090 better use 'abbreviation'.
  4091 
  4092 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4093 
  4094 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4095 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4096 significant changes for setting up numeral syntax for types:
  4097   - New constants Numeral.pred and Numeral.succ instead
  4098       of former Numeral.bin_pred and Numeral.bin_succ.
  4099   - Use integer operations instead of bin_add, bin_mult and so on.
  4100   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4101   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4102 
  4103 See src/HOL/Integ/IntArith.thy for an example setup.
  4104 
  4105 * Command 'normal_form' computes the normal form of a term that may
  4106 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4107 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4108 heavy-duty computations because the functions are compiled to ML
  4109 first.  Correspondingly, a method "normalization" is provided.  See
  4110 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4111 
  4112 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4113 25 like -->); output depends on the "iff" print_mode, the default is
  4114 "A = B" (with priority 50).
  4115 
  4116 * Relations less (<) and less_eq (<=) are also available on type bool.
  4117 Modified syntax to disallow nesting without explicit parentheses,
  4118 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4119 INCOMPATIBILITY.
  4120 
  4121 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4122 
  4123 * Relation composition operator "op O" now has precedence 75 and binds
  4124 stronger than union and intersection. INCOMPATIBILITY.
  4125 
  4126 * The old set interval syntax "{m..n(}" (and relatives) has been
  4127 removed.  Use "{m..<n}" (and relatives) instead.
  4128 
  4129 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4130 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4131 ``declare [[simproc del: neq]]''.
  4132 
  4133 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4134 True/False.
  4135 
  4136 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4137 
  4138 * Theorem setsum_mult renamed to setsum_right_distrib.
  4139 
  4140 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4141 ``rule'' method.
  4142 
  4143 * Reimplemented methods "sat" and "satx", with several improvements:
  4144 goals no longer need to be stated as "<prems> ==> False", equivalences
  4145 (i.e. "=" on type bool) are handled, variable names of the form
  4146 "lit_<n>" are no longer reserved, significant speedup.
  4147 
  4148 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4149 zChaff is still supported as well.
  4150 
  4151 * 'inductive' and 'datatype': provide projections of mutual rules,
  4152 bundled as foo_bar.inducts;
  4153 
  4154 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4155 Library.
  4156 
  4157 * Library: moved theory Accessible_Part to main HOL.
  4158 
  4159 * Library: added theory Coinductive_List of potentially infinite lists
  4160 as greatest fixed-point.
  4161 
  4162 * Library: added theory AssocList which implements (finite) maps as
  4163 association lists.
  4164 
  4165 * Method "evaluation" solves goals (i.e. a boolean expression)
  4166 efficiently by compiling it to ML.  The goal is "proved" (via an
  4167 oracle) if it evaluates to True.
  4168 
  4169 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4170 also when invoked by the simplifier.  This results in the Simplifier
  4171 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4172 Configuration option fast_arith_split_limit=0 recovers the old
  4173 behavior.
  4174 
  4175 * Support for hex (0x20) and binary (0b1001) numerals.
  4176 
  4177 * New method: reify eqs (t), where eqs are equations for an
  4178 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4179 parameter, computes a term s::'b and a list xs::'a list and proves the
  4180 theorem I xs s = t. This is also known as reification or quoting. The
  4181 resulting theorem is applied to the subgoal to substitute t with I xs
  4182 s.  If t is omitted, the subgoal itself is reified.
  4183 
  4184 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4185 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4186 where f is supposed to be a computable function (in the sense of code
  4187 generattion). The method uses reify to compute s and xs as above then
  4188 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4189 r and finally gets the theorem t = r, which is again applied to the
  4190 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4191 
  4192 * Reflection: Automatic reification now handels binding, an example is
  4193 available in src/HOL/ex/ReflectionEx.thy
  4194 
  4195 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4196 command 'statespace' that is similar to 'record', but introduces an
  4197 abstract specification based on the locale infrastructure instead of
  4198 HOL types.  This leads to extra flexibility in composing state spaces,
  4199 in particular multiple inheritance and renaming of components.
  4200 
  4201 
  4202 *** HOL-Complex ***
  4203 
  4204 * Hyperreal: Functions root and sqrt are now defined on negative real
  4205 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4206 Nonnegativity side conditions have been removed from many lemmas, so
  4207 that more subgoals may now be solved by simplification; potential
  4208 INCOMPATIBILITY.
  4209 
  4210 * Real: new type classes formalize real normed vector spaces and
  4211 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4212 and norm :: 'a => real.
  4213 
  4214 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4215 reals into other types. The overloaded constant Reals :: 'a set is now
  4216 defined as range of_real; potential INCOMPATIBILITY.
  4217 
  4218 * Real: proper support for ML code generation, including 'quickcheck'.
  4219 Reals are implemented as arbitrary precision rationals.
  4220 
  4221 * Hyperreal: Several constants that previously worked only for the
  4222 reals have been generalized, so they now work over arbitrary vector
  4223 spaces. Type annotations may need to be added in some cases; potential
  4224 INCOMPATIBILITY.
  4225 
  4226   Infinitesimal  :: ('a::real_normed_vector) star set
  4227   HFinite        :: ('a::real_normed_vector) star set
  4228   HInfinite      :: ('a::real_normed_vector) star set
  4229   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4230   monad          :: ('a::real_normed_vector) star => 'a star set
  4231   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4232   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4233   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4234   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4235   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4236   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4237   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4238   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4239   sgn            :: 'a::real_normed_vector => 'a
  4240   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4241 
  4242 * Complex: Some complex-specific constants are now abbreviations for
  4243 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4244 hnorm.  Other constants have been entirely removed in favor of the
  4245 polymorphic versions (INCOMPATIBILITY):
  4246 
  4247   approx        <-- capprox
  4248   HFinite       <-- CFinite
  4249   HInfinite     <-- CInfinite
  4250   Infinitesimal <-- CInfinitesimal
  4251   monad         <-- cmonad
  4252   galaxy        <-- cgalaxy
  4253   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4254   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4255   (ns)deriv     <-- (ns)cderiv
  4256 
  4257 
  4258 *** HOL-Algebra ***
  4259 
  4260 * Formalisation of ideals and the quotient construction over rings.
  4261 
  4262 * Order and lattice theory no longer based on records.
  4263 INCOMPATIBILITY.
  4264 
  4265 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4266 greatest_closed.  INCOMPATIBILITY.
  4267 
  4268 * Method algebra is now set up via an attribute.  For examples see
  4269 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4270 of algebraic structures.
  4271 
  4272 * Renamed theory CRing to Ring.
  4273 
  4274 
  4275 *** HOL-Nominal ***
  4276 
  4277 * Substantial, yet incomplete support for nominal datatypes (binding
  4278 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4279 src/HOL/Nominal/Examples.  Prospective users should consult
  4280 http://isabelle.in.tum.de/nominal/
  4281 
  4282 
  4283 *** ML ***
  4284 
  4285 * ML basics: just one true type int, which coincides with IntInf.int
  4286 (even on SML/NJ).
  4287 
  4288 * ML within Isar: antiquotations allow to embed statically-checked
  4289 formal entities in the source, referring to the context available at
  4290 compile-time.  For example:
  4291 
  4292 ML {* @{sort "{zero,one}"} *}
  4293 ML {* @{typ "'a => 'b"} *}
  4294 ML {* @{term "%x. x"} *}
  4295 ML {* @{prop "x == y"} *}
  4296 ML {* @{ctyp "'a => 'b"} *}
  4297 ML {* @{cterm "%x. x"} *}
  4298 ML {* @{cprop "x == y"} *}
  4299 ML {* @{thm asm_rl} *}
  4300 ML {* @{thms asm_rl} *}
  4301 ML {* @{type_name c} *}
  4302 ML {* @{type_syntax c} *}
  4303 ML {* @{const_name c} *}
  4304 ML {* @{const_syntax c} *}
  4305 ML {* @{context} *}
  4306 ML {* @{theory} *}
  4307 ML {* @{theory Pure} *}
  4308 ML {* @{theory_ref} *}
  4309 ML {* @{theory_ref Pure} *}
  4310 ML {* @{simpset} *}
  4311 ML {* @{claset} *}
  4312 ML {* @{clasimpset} *}
  4313 
  4314 The same works for sources being ``used'' within an Isar context.
  4315 
  4316 * ML in Isar: improved error reporting; extra verbosity with
  4317 ML_Context.trace enabled.
  4318 
  4319 * Pure/General/table.ML: the join operations now works via exceptions
  4320 DUP/SAME instead of type option. This is simpler in simple cases, and
  4321 admits slightly more efficient complex applications.
  4322 
  4323 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4324 use Context.generic instead of just theory.
  4325 
  4326 * Pure: datatype Context.generic joins theory/Proof.context and
  4327 provides some facilities for code that works in either kind of
  4328 context, notably GenericDataFun for uniform theory and proof data.
  4329 
  4330 * Pure: simplified internal attribute type, which is now always
  4331 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4332 local (Proof.context) attributes have been discontinued, while
  4333 minimizing code duplication. Thm.rule_attribute and
  4334 Thm.declaration_attribute build canonical attributes; see also structure
  4335 Context for further operations on Context.generic, notably
  4336 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4337 declarations and definitions.
  4338 
  4339 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4340 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4341 init only required for impure data. INCOMPATIBILITY: empty really need
  4342 to be empty (no dependencies on theory content!)
  4343 
  4344 * Pure/kernel: consts certification ignores sort constraints given in
  4345 signature declarations. (This information is not relevant to the
  4346 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4347 potential INCOMPATIBILITY.
  4348 
  4349 * Pure: axiomatic type classes are now purely definitional, with
  4350 explicit proofs of class axioms and super class relations performed
  4351 internally. See Pure/axclass.ML for the main internal interfaces --
  4352 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4353 AxClass.axiomatize_class/classrel/arity supersede
  4354 Sign.add_classes/classrel/arities.
  4355 
  4356 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4357 global/local versions on theory vs. Proof.context have been
  4358 discontinued; Attrib.syntax and Method.syntax have been adapted
  4359 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4360 attributes, methods, etc.
  4361 
  4362 * Pure: several functions of signature "... -> theory -> theory * ..."
  4363 have been reoriented to "... -> theory -> ... * theory" in order to
  4364 allow natural usage in combination with the ||>, ||>>, |-> and
  4365 fold_map combinators.
  4366 
  4367 * Pure: official theorem names (closed derivations) and additional
  4368 comments (tags) are now strictly separate.  Name hints -- which are
  4369 maintained as tags -- may be attached any time without affecting the
  4370 derivation.
  4371 
  4372 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4373 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4374 achieve the old behaviour.
  4375 
  4376 * Pure: the "Goal" constant is now called "prop", supporting a
  4377 slightly more general idea of ``protecting'' meta-level rule
  4378 statements.
  4379 
  4380 * Pure: Logic.(un)varify only works in a global context, which is now
  4381 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4382 Logic.legacy_(un)varify as temporary workaround.
  4383 
  4384 * Pure: structure Name provides scalable operations for generating
  4385 internal variable names, notably Name.variants etc.  This replaces
  4386 some popular functions from term.ML:
  4387 
  4388   Term.variant		->  Name.variant
  4389   Term.variantlist	->  Name.variant_list
  4390   Term.invent_names	->  Name.invent_list
  4391 
  4392 Note that low-level renaming rarely occurs in new code -- operations
  4393 from structure Variable are used instead (see below).
  4394 
  4395 * Pure: structure Variable provides fundamental operations for proper
  4396 treatment of fixed/schematic variables in a context.  For example,
  4397 Variable.import introduces fixes for schematics of given facts and
  4398 Variable.export reverses the effect (up to renaming) -- this replaces
  4399 various freeze_thaw operations.
  4400 
  4401 * Pure: structure Goal provides simple interfaces for
  4402 init/conclude/finish and tactical prove operations (replacing former
  4403 Tactic.prove).  Goal.prove is the canonical way to prove results
  4404 within a given context; Goal.prove_global is a degraded version for
  4405 theory level goals, including a global Drule.standard.  Note that
  4406 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4407 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4408 in a locale context).
  4409 
  4410 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4411 and type checking (Syntax.check_term etc.), with common combinations
  4412 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4413 which are considered legacy and await removal.
  4414 
  4415 * Pure/Syntax: generic interfaces for type unchecking
  4416 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4417 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4418 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4419 available for convenience, but refer to the very same operations using
  4420 a mere theory instead of a full context.
  4421 
  4422 * Isar: simplified treatment of user-level errors, using exception
  4423 ERROR of string uniformly.  Function error now merely raises ERROR,
  4424 without any side effect on output channels.  The Isar toplevel takes
  4425 care of proper display of ERROR exceptions.  ML code may use plain
  4426 handle/can/try; cat_error may be used to concatenate errors like this:
  4427 
  4428   ... handle ERROR msg => cat_error msg "..."
  4429 
  4430 Toplevel ML code (run directly or through the Isar toplevel) may be
  4431 embedded into the Isar toplevel with exception display/debug like
  4432 this:
  4433 
  4434   Isar.toplevel (fn () => ...)
  4435 
  4436 INCOMPATIBILITY, removed special transform_error facilities, removed
  4437 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4438 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4439 -- use plain ERROR instead.
  4440 
  4441 * Isar: theory setup now has type (theory -> theory), instead of a
  4442 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4443 
  4444 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4445 ProofContext.debug/verbose flags.
  4446 
  4447 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4448 theory before entering a proof state.  Transactions now always see a
  4449 quasi-functional intermediate checkpoint, both in interactive and
  4450 batch mode.
  4451 
  4452 * Isar: simplified interfaces for outer syntax.  Renamed
  4453 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4454 OuterSyntax.add_parsers -- this functionality is now included in
  4455 OuterSyntax.command etc.  INCOMPATIBILITY.
  4456 
  4457 * Simplifier: the simpset of a running simplification process now
  4458 contains a proof context (cf. Simplifier.the_context), which is the
  4459 very context that the initial simpset has been retrieved from (by
  4460 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4461 (solver, looper etc.) may depend on arbitrary proof data.
  4462 
  4463 * Simplifier.inherit_context inherits the proof context (plus the
  4464 local bounds) of the current simplification process; any simproc
  4465 etc. that calls the Simplifier recursively should do this!  Removed
  4466 former Simplifier.inherit_bounds, which is already included here --
  4467 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4468 specify an explicit context using Simplifier.context/theory_context.
  4469 
  4470 * Simplifier/Classical Reasoner: more abstract interfaces
  4471 change_simpset/claset for modifying the simpset/claset reference of a
  4472 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4473 INCOMPATIBILITY.
  4474 
  4475 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4476 "Trueprop" etc.
  4477 
  4478 
  4479 *** System ***
  4480 
  4481 * settings: the default heap location within ISABELLE_HOME_USER now
  4482 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4483 Isabelle installations.
  4484 
  4485 * isabelle-process: option -S (secure mode) disables some critical
  4486 operations, notably runtime compilation and evaluation of ML source
  4487 code.
  4488 
  4489 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4490 
  4491 * Support for parallel execution, using native multicore support of
  4492 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4493 independent theories, according to the given theory header
  4494 specifications. The maximum number of worker threads is specified via
  4495 usedir option -M or the "max-threads" setting in Proof General. A
  4496 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4497 to 6 on a 8-core machine.  User-code needs to observe certain
  4498 guidelines for thread-safe programming, see appendix A in the Isar
  4499 Implementation manual.
  4500 
  4501 
  4502 
  4503 New in Isabelle2005 (October 2005)
  4504 ----------------------------------
  4505 
  4506 *** General ***
  4507 
  4508 * Theory headers: the new header syntax for Isar theories is
  4509 
  4510   theory <name>
  4511   imports <theory1> ... <theoryN>
  4512   uses <file1> ... <fileM>
  4513   begin
  4514 
  4515 where the 'uses' part is optional.  The previous syntax
  4516 
  4517   theory <name> = <theory1> + ... + <theoryN>:
  4518 
  4519 will disappear in the next release.  Use isatool fixheaders to convert
  4520 existing theory files.  Note that there is no change in ancient
  4521 non-Isar theories now, but these will disappear soon.
  4522 
  4523 * Theory loader: parent theories can now also be referred to via
  4524 relative and absolute paths.
  4525 
  4526 * Command 'find_theorems' searches for a list of criteria instead of a
  4527 list of constants. Known criteria are: intro, elim, dest, name:string,
  4528 simp:term, and any term. Criteria can be preceded by '-' to select
  4529 theorems that do not match. Intro, elim, dest select theorems that
  4530 match the current goal, name:s selects theorems whose fully qualified
  4531 name contain s, and simp:term selects all simplification rules whose
  4532 lhs match term.  Any other term is interpreted as pattern and selects
  4533 all theorems matching the pattern. Available in ProofGeneral under
  4534 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4535 
  4536   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4537 
  4538 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4539 matching the current goal as introduction rule and not having "HOL."
  4540 in their name (i.e. not being defined in theory HOL).
  4541 
  4542 * Command 'thms_containing' has been discontinued in favour of
  4543 'find_theorems'; INCOMPATIBILITY.
  4544 
  4545 * Communication with Proof General is now 8bit clean, which means that
  4546 Unicode text in UTF-8 encoding may be used within theory texts (both
  4547 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4548 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4549 
  4550   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4551   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4552 
  4553 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4554 Classical Reasoner.  Typical big applications run around 2 times
  4555 faster.
  4556 
  4557 
  4558 *** Document preparation ***
  4559 
  4560 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4561 of raw sources.  Only those symbols that do not require additional
  4562 LaTeX packages (depending on comments in isabellesym.sty) are
  4563 displayed properly, everything else is left verbatim.  isatool display
  4564 and isatool print are used as front ends (these are subject to the
  4565 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4566 
  4567 * Command tags control specific markup of certain regions of text,
  4568 notably folding and hiding.  Predefined tags include "theory" (for
  4569 theory begin and end), "proof" for proof commands, and "ML" for
  4570 commands involving ML code; the additional tags "visible" and
  4571 "invisible" are unused by default.  Users may give explicit tag
  4572 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4573 interpretation of tags is determined by the LaTeX job during document
  4574 preparation: see option -V of isatool usedir, or options -n and -t of
  4575 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4576 \isadroptag.
  4577 
  4578 Several document versions may be produced at the same time via isatool
  4579 usedir (the generated index.html will link all of them).  Typical
  4580 specifications include ''-V document=theory,proof,ML'' to present
  4581 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4582 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4583 these parts without any formal replacement text.  The Isabelle site
  4584 default settings produce ''document'' and ''outline'' versions as
  4585 specified above.
  4586 
  4587 * Several new antiquotations:
  4588 
  4589   @{term_type term} prints a term with its type annotated;
  4590 
  4591   @{typeof term} prints the type of a term;
  4592 
  4593   @{const const} is the same as @{term const}, but checks that the
  4594   argument is a known logical constant;
  4595 
  4596   @{term_style style term} and @{thm_style style thm} print a term or
  4597   theorem applying a "style" to it
  4598 
  4599   @{ML text}
  4600 
  4601 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4602 definitions, equations, inequations etc., 'concl' printing only the
  4603 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4604 to print the specified premise.  TermStyle.add_style provides an ML
  4605 interface for introducing further styles.  See also the "LaTeX Sugar"
  4606 document practical applications.  The ML antiquotation prints
  4607 type-checked ML expressions verbatim.
  4608 
  4609 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4610 and 'text' support optional locale specification '(in loc)', which
  4611 specifies the default context for interpreting antiquotations.  For
  4612 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4613 
  4614 * Option 'locale=NAME' of antiquotations specifies an alternative
  4615 context interpreting the subsequent argument.  For example: @{thm
  4616 [locale=lattice] inf_assoc}.
  4617 
  4618 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4619 a proof context.
  4620 
  4621 * Proper output of antiquotations for theory commands involving a
  4622 proof context (such as 'locale' or 'theorem (in loc) ...').
  4623 
  4624 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4625 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4626 
  4627 * isatool usedir: new option -C (default true) controls whether option
  4628 -D should include a copy of the original document directory; -C false
  4629 prevents unwanted effects such as copying of administrative CVS data.
  4630 
  4631 
  4632 *** Pure ***
  4633 
  4634 * Considerably improved version of 'constdefs' command.  Now performs
  4635 automatic type-inference of declared constants; additional support for
  4636 local structure declarations (cf. locales and HOL records), see also
  4637 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4638 sequential dependencies of definitions within a single 'constdefs'
  4639 section; moreover, the declared name needs to be an identifier.  If
  4640 all fails, consider to fall back on 'consts' and 'defs' separately.
  4641 
  4642 * Improved indexed syntax and implicit structures.  First of all,
  4643 indexed syntax provides a notational device for subscripted
  4644 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4645 expressions.  Secondly, in a local context with structure
  4646 declarations, number indexes \<^sub>n or the empty index (default
  4647 number 1) refer to a certain fixed variable implicitly; option
  4648 show_structs controls printing of implicit structures.  Typical
  4649 applications of these concepts involve record types and locales.
  4650 
  4651 * New command 'no_syntax' removes grammar declarations (and
  4652 translations) resulting from the given syntax specification, which is
  4653 interpreted in the same manner as for the 'syntax' command.
  4654 
  4655 * 'Advanced' translation functions (parse_translation etc.) may depend
  4656 on the signature of the theory context being presently used for
  4657 parsing/printing, see also isar-ref manual.
  4658 
  4659 * Improved 'oracle' command provides a type-safe interface to turn an
  4660 ML expression of type theory -> T -> term into a primitive rule of
  4661 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4662 is already included here); see also FOL/ex/IffExample.thy;
  4663 INCOMPATIBILITY.
  4664 
  4665 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4666 before); "cI" is no longer bound, use "c.intro" instead.
  4667 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4668 axclasses vs. locales.
  4669 
  4670 * Improved internal renaming of symbolic identifiers -- attach primes
  4671 instead of base 26 numbers.
  4672 
  4673 * New flag show_question_marks controls printing of leading question
  4674 marks in schematic variable names.
  4675 
  4676 * In schematic variable names, *any* symbol following \<^isub> or
  4677 \<^isup> is now treated as part of the base name.  For example, the
  4678 following works without printing of awkward ".0" indexes:
  4679 
  4680   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4681     by simp
  4682 
  4683 * Inner syntax includes (*(*nested*) comments*).
  4684 
  4685 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4686 annotations as "(00...)".
  4687 
  4688 * Clear separation of logical types and nonterminals, where the latter
  4689 may only occur in 'syntax' specifications or type abbreviations.
  4690 Before that distinction was only partially implemented via type class
  4691 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4692 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4693 exotic syntax specifications may require further adaption
  4694 (e.g. Cube/Cube.thy).
  4695 
  4696 * Removed obsolete type class "logic", use the top sort {} instead.
  4697 Note that non-logical types should be declared as 'nonterminals'
  4698 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4699 specifications.
  4700 
  4701 * Attributes 'induct' and 'cases': type or set names may now be
  4702 locally fixed variables as well.
  4703 
  4704 * Simplifier: can now control the depth to which conditional rewriting
  4705 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4706 Limit.
  4707 
  4708 * Simplifier: simplification procedures may now take the current
  4709 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4710 interface), which is very useful for calling the Simplifier
  4711 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4712 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4713 low-level mk_simproc no longer applies Logic.varify internally, to
  4714 allow for use in a context of fixed variables.
  4715 
  4716 * thin_tac now works even if the assumption being deleted contains !!
  4717 or ==>.  More generally, erule now works even if the major premise of
  4718 the elimination rule contains !! or ==>.
  4719 
  4720 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4721 
  4722 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4723 from Pure, which contains all common declarations already.  Both
  4724 theories are defined via plain Isabelle/Isar .thy files.
  4725 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4726 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4727 use isatool fixcpure to adapt your theory and ML sources.
  4728 
  4729 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4730 selections of theorems in named facts via index ranges.
  4731 
  4732 * 'print_theorems': in theory mode, really print the difference
  4733 wrt. the last state (works for interactive theory development only),
  4734 in proof mode print all local facts (cf. 'print_facts');
  4735 
  4736 * 'hide': option '(open)' hides only base names.
  4737 
  4738 * More efficient treatment of intermediate checkpoints in interactive
  4739 theory development.
  4740 
  4741 * Code generator is now invoked via code_module (incremental code
  4742 generation) and code_library (modular code generation, ML structures
  4743 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4744 must be quoted when used as identifiers.
  4745 
  4746 * New 'value' command for reading, evaluating and printing terms using
  4747 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4748 quoted when used as identifier.
  4749 
  4750 
  4751 *** Locales ***
  4752 
  4753 * New commands for the interpretation of locale expressions in
  4754 theories (1), locales (2) and proof contexts (3).  These generate
  4755 proof obligations from the expression specification.  After the
  4756 obligations have been discharged, theorems of the expression are added
  4757 to the theory, target locale or proof context.  The synopsis of the
  4758 commands is a follows:
  4759 
  4760   (1) interpretation expr inst
  4761   (2) interpretation target < expr
  4762   (3) interpret expr inst
  4763 
  4764 Interpretation in theories and proof contexts require a parameter
  4765 instantiation of terms from the current context.  This is applied to
  4766 specifications and theorems of the interpreted expression.
  4767 Interpretation in locales only permits parameter renaming through the
  4768 locale expression.  Interpretation is smart in that interpretations
  4769 that are active already do not occur in proof obligations, neither are
  4770 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4771 inspect active interpretations of a particular locale.  For details,
  4772 see the Isar Reference manual.  Examples can be found in
  4773 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4774 
  4775 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4776 'interpret' instead.
  4777 
  4778 * New context element 'constrains' for adding type constraints to
  4779 parameters.
  4780 
  4781 * Context expressions: renaming of parameters with syntax
  4782 redeclaration.
  4783 
  4784 * Locale declaration: 'includes' disallowed.
  4785 
  4786 * Proper static binding of attribute syntax -- i.e. types / terms /
  4787 facts mentioned as arguments are always those of the locale definition
  4788 context, independently of the context of later invocations.  Moreover,
  4789 locale operations (renaming and type / term instantiation) are applied
  4790 to attribute arguments as expected.
  4791 
  4792 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4793 actual attributes; rare situations may require Attrib.attribute to
  4794 embed those attributes into Attrib.src that lack concrete syntax.
  4795 Attribute implementations need to cooperate properly with the static
  4796 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4797 Attrib.XXX_thm etc. already do the right thing without further
  4798 intervention.  Only unusual applications -- such as "where" or "of"
  4799 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4800 on the context and the facts involved -- may have to assign parsed
  4801 values to argument tokens explicitly.
  4802 
  4803 * Changed parameter management in theorem generation for long goal
  4804 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4805 theorem statement in rare situations.
  4806 
  4807 * Locale inspection command 'print_locale' omits notes elements.  Use
  4808 'print_locale!' to have them included in the output.
  4809 
  4810 
  4811 *** Provers ***
  4812 
  4813 * Provers/hypsubst.ML: improved version of the subst method, for
  4814 single-step rewriting: it now works in bound variable contexts. New is
  4815 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4816 rewrite a different subterm than the original subst method, which is
  4817 still available as 'simplesubst'.
  4818 
  4819 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4820 and quasi orders.
  4821 
  4822 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4823 reflexive-transitive closure of relations.
  4824 
  4825 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4826 limit (previously hard-coded with a value of 20) user-definable.
  4827 
  4828 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4829 is peformed already.  Object-logics merely need to finish their
  4830 initial simpset configuration as before.  INCOMPATIBILITY.
  4831 
  4832 
  4833 *** HOL ***
  4834 
  4835 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4836 
  4837   syntax (epsilon)
  4838     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4839 
  4840 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4841 and x-symbol; use option '-m epsilon' to get it actually printed.
  4842 Moreover, the mathematically important symbolic identifier \<epsilon>
  4843 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4844 
  4845 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  4846 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  4847 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  4848 support corresponding Isar calculations.
  4849 
  4850 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  4851 instead of ":".
  4852 
  4853 * theory SetInterval: changed the syntax for open intervals:
  4854 
  4855   Old       New
  4856   {..n(}    {..<n}
  4857   {)n..}    {n<..}
  4858   {m..n(}   {m..<n}
  4859   {)m..n}   {m<..n}
  4860   {)m..n(}  {m<..<n}
  4861 
  4862 The old syntax is still supported but will disappear in the next
  4863 release.  For conversion use the following Emacs search and replace
  4864 patterns (these are not perfect but work quite well):
  4865 
  4866   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  4867   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  4868 
  4869 * Theory Commutative_Ring (in Library): method comm_ring for proving
  4870 equalities in commutative rings; method 'algebra' provides a generic
  4871 interface.
  4872 
  4873 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  4874 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  4875 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  4876 be a tuple pattern.
  4877 
  4878 Some new syntax forms are available:
  4879 
  4880   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  4881   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  4882   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  4883   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  4884 
  4885 The latter form "\<Sum>x < k. e" used to be based on a separate
  4886 function "Summation", which has been discontinued.
  4887 
  4888 * theory Finite_Set: in structured induction proofs, the insert case
  4889 is now 'case (insert x F)' instead of the old counterintuitive 'case
  4890 (insert F x)'.
  4891 
  4892 * The 'refute' command has been extended to support a much larger
  4893 fragment of HOL, including axiomatic type classes, constdefs and
  4894 typedefs, inductive datatypes and recursion.
  4895 
  4896 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  4897 Requires zChaff with proof generation to be installed.  See
  4898 HOL/ex/SAT_Examples.thy for examples.
  4899 
  4900 * Datatype induction via method 'induct' now preserves the name of the
  4901 induction variable. For example, when proving P(xs::'a list) by
  4902 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  4903 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  4904 in unstructured proof scripts.
  4905 
  4906 * Reworked implementation of records.  Improved scalability for
  4907 records with many fields, avoiding performance problems for type
  4908 inference. Records are no longer composed of nested field types, but
  4909 of nested extension types. Therefore the record type only grows linear
  4910 in the number of extensions and not in the number of fields.  The
  4911 top-level (users) view on records is preserved.  Potential
  4912 INCOMPATIBILITY only in strange cases, where the theory depends on the
  4913 old record representation. The type generated for a record is called
  4914 <record_name>_ext_type.
  4915 
  4916 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  4917 proofs triggered by a record definition or a simproc (if
  4918 quick_and_dirty is enabled).  Definitions of large records can take
  4919 quite long.
  4920 
  4921 New simproc record_upd_simproc for simplification of multiple record
  4922 updates enabled by default.  Moreover, trivial updates are also
  4923 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  4924 occasionally, since simplification is more powerful by default.
  4925 
  4926 * typedef: proper support for polymorphic sets, which contain extra
  4927 type-variables in the term.
  4928 
  4929 * Simplifier: automatically reasons about transitivity chains
  4930 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  4931 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  4932 old proofs break occasionally as simplification may now solve more
  4933 goals than previously.
  4934 
  4935 * Simplifier: converts x <= y into x = y if assumption y <= x is
  4936 present.  Works for all partial orders (class "order"), in particular
  4937 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  4938 just like y <= x.
  4939 
  4940 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  4941 bound variable or a constant then the let is unfolded.  Otherwise
  4942 first a is simplified to b, and then f b is simplified to g. If
  4943 possible we abstract b from g arriving at "let x = b in h x",
  4944 otherwise we unfold the let and arrive at g.  The simproc can be
  4945 enabled/disabled by the reference use_let_simproc.  Potential
  4946 INCOMPATIBILITY since simplification is more powerful by default.
  4947 
  4948 * Classical reasoning: the meson method now accepts theorems as arguments.
  4949 
  4950 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  4951 jobs to provide advice on the provability of subgoals.
  4952 
  4953 * Theory OrderedGroup and Ring_and_Field: various additions and
  4954 improvements to faciliate calculations involving equalities and
  4955 inequalities.
  4956 
  4957 The following theorems have been eliminated or modified
  4958 (INCOMPATIBILITY):
  4959 
  4960   abs_eq             now named abs_of_nonneg
  4961   abs_of_ge_0        now named abs_of_nonneg
  4962   abs_minus_eq       now named abs_of_nonpos
  4963   imp_abs_id         now named abs_of_nonneg
  4964   imp_abs_neg_id     now named abs_of_nonpos
  4965   mult_pos           now named mult_pos_pos
  4966   mult_pos_le        now named mult_nonneg_nonneg
  4967   mult_pos_neg_le    now named mult_nonneg_nonpos
  4968   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  4969   mult_neg           now named mult_neg_neg
  4970   mult_neg_le        now named mult_nonpos_nonpos
  4971 
  4972 * The following lemmas in Ring_and_Field have been added to the simplifier:
  4973      
  4974      zero_le_square
  4975      not_square_less_zero 
  4976 
  4977   The following lemmas have been deleted from Real/RealPow:
  4978   
  4979      realpow_zero_zero
  4980      realpow_two
  4981      realpow_less
  4982      zero_le_power
  4983      realpow_two_le
  4984      abs_realpow_two
  4985      realpow_two_abs     
  4986 
  4987 * Theory Parity: added rules for simplifying exponents.
  4988 
  4989 * Theory List:
  4990 
  4991 The following theorems have been eliminated or modified
  4992 (INCOMPATIBILITY):
  4993 
  4994   list_all_Nil       now named list_all.simps(1)
  4995   list_all_Cons      now named list_all.simps(2)
  4996   list_all_conv      now named list_all_iff
  4997   set_mem_eq         now named mem_iff
  4998 
  4999 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5000 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5001 
  5002 
  5003 *** HOL-Complex ***
  5004 
  5005 * Theory RealDef: better support for embedding natural numbers and
  5006 integers in the reals.
  5007 
  5008 The following theorems have been eliminated or modified
  5009 (INCOMPATIBILITY):
  5010 
  5011   exp_ge_add_one_self  now requires no hypotheses
  5012   real_of_int_add      reversed direction of equality (use [symmetric])
  5013   real_of_int_minus    reversed direction of equality (use [symmetric])
  5014   real_of_int_diff     reversed direction of equality (use [symmetric])
  5015   real_of_int_mult     reversed direction of equality (use [symmetric])
  5016 
  5017 * Theory RComplete: expanded support for floor and ceiling functions.
  5018 
  5019 * Theory Ln is new, with properties of the natural logarithm
  5020 
  5021 * Hyperreal: There is a new type constructor "star" for making
  5022 nonstandard types.  The old type names are now type synonyms:
  5023 
  5024   hypreal = real star
  5025   hypnat = nat star
  5026   hcomplex = complex star
  5027 
  5028 * Hyperreal: Many groups of similarly-defined constants have been
  5029 replaced by polymorphic versions (INCOMPATIBILITY):
  5030 
  5031   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5032 
  5033   starset      <-- starsetNat, starsetC
  5034   *s*          <-- *sNat*, *sc*
  5035   starset_n    <-- starsetNat_n, starsetC_n
  5036   *sn*         <-- *sNatn*, *scn*
  5037   InternalSets <-- InternalNatSets, InternalCSets
  5038 
  5039   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5040   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5041   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5042   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5043   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5044 
  5045 * Hyperreal: Many type-specific theorems have been removed in favor of
  5046 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5047 
  5048   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5049   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5050   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5051   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5052   right_minus <-- hypreal_add_minus
  5053   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5054   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5055   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5056   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5057   mult_1_right <-- hcomplex_mult_one_right
  5058   mult_zero_left <-- hcomplex_mult_zero_left
  5059   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5060   right_distrib <-- hypnat_add_mult_distrib2
  5061   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5062   right_inverse <-- hypreal_mult_inverse
  5063   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5064   order_refl <-- {hypreal,hypnat}_le_refl
  5065   order_trans <-- {hypreal,hypnat}_le_trans
  5066   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5067   order_less_le <-- {hypreal,hypnat}_less_le
  5068   linorder_linear <-- {hypreal,hypnat}_le_linear
  5069   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5070   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5071   add_nonneg_nonneg <-- hypreal_le_add_order
  5072 
  5073 * Hyperreal: Separate theorems having to do with type-specific
  5074 versions of constants have been merged into theorems that apply to the
  5075 new polymorphic constants (INCOMPATIBILITY):
  5076 
  5077   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5078   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5079   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5080   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5081   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5082   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5083   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5084   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5085   STAR_diff <-- {STAR,STARC}_diff
  5086   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5087     STARC_hcomplex_of_complex}_image_subset
  5088   starset_n_Un <-- starset{Nat,C}_n_Un
  5089   starset_n_Int <-- starset{Nat,C}_n_Int
  5090   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5091   starset_n_diff <-- starset{Nat,C}_n_diff
  5092   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5093   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5094   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5095   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5096   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5097   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5098   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5099   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5100   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5101   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5102   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5103   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5104   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5105   starfun_diff <-- starfun{C,RC,CR}_diff
  5106   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5107   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5108   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5109   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5110   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5111   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5112   starfun_Id <-- starfunC_Id
  5113   starfun_approx <-- starfun{Nat,CR}_approx
  5114   starfun_capprox <-- starfun{C,RC}_capprox
  5115   starfun_abs <-- starfunNat_rabs
  5116   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5117   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5118   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5119   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5120   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5121   starfun_add_approx <-- starfunCR_add_approx
  5122   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5123   starfun_divide <-- starfun{C,CR,RC}_divide
  5124   starfun_n <-- starfun{Nat,C}_n
  5125   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5126   starfun_n_add <-- starfun{Nat,C}_n_add
  5127   starfun_n_add_minus <-- starfunNat_n_add_minus
  5128   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5129   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5130   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5131 
  5132   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5133   star_n_minus <-- {hypreal,hcomplex}_minus
  5134   star_n_diff <-- {hypreal,hcomplex}_diff
  5135   star_n_mult <-- {hypreal,hcomplex}_mult
  5136   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5137   star_n_le <-- {hypreal,hypnat}_le
  5138   star_n_less <-- {hypreal,hypnat}_less
  5139   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5140   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5141   star_n_abs <-- hypreal_hrabs
  5142   star_n_divide <-- hcomplex_divide
  5143 
  5144   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5145   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5146   star_of_diff <-- hypreal_of_real_diff
  5147   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5148   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5149   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5150   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5151   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5152   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5153   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5154   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5155   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5156   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5157   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5158   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5159   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5160   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5161   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5162   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5163   star_of_power <-- hypreal_of_real_power
  5164   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5165 
  5166 * Hyperreal: new method "transfer" that implements the transfer
  5167 principle of nonstandard analysis. With a subgoal that mentions
  5168 nonstandard types like "'a star", the command "apply transfer"
  5169 replaces it with an equivalent one that mentions only standard types.
  5170 To be successful, all free variables must have standard types; non-
  5171 standard variables must have explicit universal quantifiers.
  5172 
  5173 * Hyperreal: A theory of Taylor series.
  5174 
  5175 
  5176 *** HOLCF ***
  5177 
  5178 * Discontinued special version of 'constdefs' (which used to support
  5179 continuous functions) in favor of the general Pure one with full
  5180 type-inference.
  5181 
  5182 * New simplification procedure for solving continuity conditions; it
  5183 is much faster on terms with many nested lambda abstractions (cubic
  5184 instead of exponential time).
  5185 
  5186 * New syntax for domain package: selector names are now optional.
  5187 Parentheses should be omitted unless argument is lazy, for example:
  5188 
  5189   domain 'a stream = cons "'a" (lazy "'a stream")
  5190 
  5191 * New command 'fixrec' for defining recursive functions with pattern
  5192 matching; defining multiple functions with mutual recursion is also
  5193 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5194 sinr, or any data constructor defined by the domain package. The given
  5195 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5196 syntax and examples.
  5197 
  5198 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5199 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5200 but the proof obligation additionally includes an admissibility
  5201 requirement. The packages generate instances of class cpo or pcpo,
  5202 with continuity and strictness theorems for Rep and Abs.
  5203 
  5204 * HOLCF: Many theorems have been renamed according to a more standard naming
  5205 scheme (INCOMPATIBILITY):
  5206 
  5207   foo_inject:  "foo$x = foo$y ==> x = y"
  5208   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5209   foo_less:    "(foo$x << foo$y) = (x << y)"
  5210   foo_strict:  "foo$UU = UU"
  5211   foo_defined: "... ==> foo$x ~= UU"
  5212   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5213 
  5214 
  5215 *** ZF ***
  5216 
  5217 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5218 including the First Isomorphism Theorem (on quotienting by the kernel
  5219 of a homomorphism).
  5220 
  5221 * ZF/Simplifier: install second copy of type solver that actually
  5222 makes use of TC rules declared to Isar proof contexts (or locales);
  5223 the old version is still required for ML proof scripts.
  5224 
  5225 
  5226 *** Cube ***
  5227 
  5228 * Converted to Isar theory format; use locales instead of axiomatic
  5229 theories.
  5230 
  5231 
  5232 *** ML ***
  5233 
  5234 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5235 for ||>, ||>>, |>>,
  5236 
  5237 * Pure/library.ML no longer defines its own option datatype, but uses
  5238 that of the SML basis, which has constructors NONE and SOME instead of
  5239 None and Some, as well as exception Option.Option instead of OPTION.
  5240 The functions the, if_none, is_some, is_none have been adapted
  5241 accordingly, while Option.map replaces apsome.
  5242 
  5243 * Pure/library.ML: the exception LIST has been given up in favour of
  5244 the standard exceptions Empty and Subscript, as well as
  5245 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5246 superceded by the standard hd and tl functions etc.
  5247 
  5248 A number of basic list functions are no longer exported to the ML
  5249 toplevel, as they are variants of predefined functions.  The following
  5250 suggests how one can translate existing code:
  5251 
  5252     rev_append xs ys = List.revAppend (xs, ys)
  5253     nth_elem (i, xs) = List.nth (xs, i)
  5254     last_elem xs = List.last xs
  5255     flat xss = List.concat xss
  5256     seq fs = List.app fs
  5257     partition P xs = List.partition P xs
  5258     mapfilter f xs = List.mapPartial f xs
  5259 
  5260 * Pure/library.ML: several combinators for linear functional
  5261 transformations, notably reverse application and composition:
  5262 
  5263   x |> f                f #> g
  5264   (x, y) |-> f          f #-> g
  5265 
  5266 * Pure/library.ML: introduced/changed precedence of infix operators:
  5267 
  5268   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5269   infix 2 ?;
  5270   infix 3 o oo ooo oooo;
  5271   infix 4 ~~ upto downto;
  5272 
  5273 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5274 infix operators.
  5275 
  5276 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5277 fold_map support linear functional transformations and nesting.  For
  5278 example:
  5279 
  5280   fold f [x1, ..., xN] y =
  5281     y |> f x1 |> ... |> f xN
  5282 
  5283   (fold o fold) f [xs1, ..., xsN] y =
  5284     y |> fold f xs1 |> ... |> fold f xsN
  5285 
  5286   fold f [x1, ..., xN] =
  5287     f x1 #> ... #> f xN
  5288 
  5289   (fold o fold) f [xs1, ..., xsN] =
  5290     fold f xs1 #> ... #> fold f xsN
  5291 
  5292 * Pure/library.ML: the following selectors on type 'a option are
  5293 available:
  5294 
  5295   the:               'a option -> 'a  (*partial*)
  5296   these:             'a option -> 'a  where 'a = 'b list
  5297   the_default: 'a -> 'a option -> 'a
  5298   the_list:          'a option -> 'a list
  5299 
  5300 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5301 basic operations for association lists, following natural argument
  5302 order; moreover the explicit equality predicate passed here avoids
  5303 potentially expensive polymorphic runtime equality checks.
  5304 The old functions may be expressed as follows:
  5305 
  5306   assoc = uncurry (AList.lookup (op =))
  5307   assocs = these oo AList.lookup (op =)
  5308   overwrite = uncurry (AList.update (op =)) o swap
  5309 
  5310 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5311 
  5312   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5313   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5314 
  5315 replacing make_keylist and keyfilter (occassionally used)
  5316 Naive rewrites:
  5317 
  5318   make_keylist = AList.make
  5319   keyfilter = AList.find (op =)
  5320 
  5321 * eq_fst and eq_snd now take explicit equality parameter, thus
  5322   avoiding eqtypes. Naive rewrites:
  5323 
  5324     eq_fst = eq_fst (op =)
  5325     eq_snd = eq_snd (op =)
  5326 
  5327 * Removed deprecated apl and apr (rarely used).
  5328   Naive rewrites:
  5329 
  5330     apl (n, op) =>>= curry op n
  5331     apr (op, m) =>>= fn n => op (n, m)
  5332 
  5333 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5334 provides a reasonably efficient light-weight implementation of sets as
  5335 lists.
  5336 
  5337 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5338 few new operations; existing lookup and update are now curried to
  5339 follow natural argument order (for use with fold etc.);
  5340 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5341 
  5342 * Pure/General: output via the Isabelle channels of
  5343 writeln/warning/error etc. is now passed through Output.output, with a
  5344 hook for arbitrary transformations depending on the print_mode
  5345 (cf. Output.add_mode -- the first active mode that provides a output
  5346 function wins).  Already formatted output may be embedded into further
  5347 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5348 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5349 accommodate easy composition of diagnostic messages etc.  Programmers
  5350 rarely need to care about Output.output or Output.raw at all, with
  5351 some notable exceptions: Output.output is required when bypassing the
  5352 standard channels (writeln etc.), or in token translations to produce
  5353 properly formatted results; Output.raw is required when capturing
  5354 already output material that will eventually be presented to the user
  5355 a second time.  For the default print mode, both Output.output and
  5356 Output.raw have no effect.
  5357 
  5358 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5359 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5360 cumulative results are displayed at the end of a batch session.
  5361 
  5362 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5363 replaced by File.platform_path and File.shell_path (with appropriate
  5364 hooks).  This provides a clean interface for unusual systems where the
  5365 internal and external process view of file names are different.
  5366 
  5367 * Pure: more efficient orders for basic syntactic entities: added
  5368 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5369 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5370 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5371 orders now -- potential INCOMPATIBILITY for code that depends on a
  5372 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5373 Library.sort_strings on result).
  5374 
  5375 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5376 fold_types traverse types/terms from left to right, observing natural
  5377 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5378 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5379 
  5380 * Pure: name spaces have been refined, with significant changes of the
  5381 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5382 to extern(_table).  The plain name entry path is superceded by a
  5383 general 'naming' context, which also includes the 'policy' to produce
  5384 a fully qualified name and external accesses of a fully qualified
  5385 name; NameSpace.extend is superceded by context dependent
  5386 Sign.declare_name.  Several theory and proof context operations modify
  5387 the naming context.  Especially note Theory.restore_naming and
  5388 ProofContext.restore_naming to get back to a sane state; note that
  5389 Theory.add_path is no longer sufficient to recover from
  5390 Theory.absolute_path in particular.
  5391 
  5392 * Pure: new flags short_names (default false) and unique_names
  5393 (default true) for controlling output of qualified names.  If
  5394 short_names is set, names are printed unqualified.  If unique_names is
  5395 reset, the name prefix is reduced to the minimum required to achieve
  5396 the original result when interning again, even if there is an overlap
  5397 with earlier declarations.
  5398 
  5399 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5400 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5401 (useful for printing error messages).  INCOMPATIBILITY.
  5402 
  5403 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5404 Theory.theory are now identified, referring to the universal
  5405 Context.theory (see Pure/context.ML).  Actual signature and theory
  5406 content is managed as theory data.  The old code and interfaces were
  5407 spread over many files and structures; the new arrangement introduces
  5408 considerable INCOMPATIBILITY to gain more clarity:
  5409 
  5410   Context -- theory management operations (name, identity, inclusion,
  5411     parents, ancestors, merge, etc.), plus generic theory data;
  5412 
  5413   Sign -- logical signature and syntax operations (declaring consts,
  5414     types, etc.), plus certify/read for common entities;
  5415 
  5416   Theory -- logical theory operations (stating axioms, definitions,
  5417     oracles), plus a copy of logical signature operations (consts,
  5418     types, etc.); also a few basic management operations (Theory.copy,
  5419     Theory.merge, etc.)
  5420 
  5421 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5422 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5423 for convenience -- they merely return the theory.
  5424 
  5425 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5426 
  5427 * Pure: the Isar proof context type is already defined early in Pure
  5428 as Context.proof (note that ProofContext.context and Proof.context are
  5429 aliases, where the latter is the preferred name).  This enables other
  5430 Isabelle components to refer to that type even before Isar is present.
  5431 
  5432 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5433 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5434 any of these kinds.  For example, Sign.intern typeK is now
  5435 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5436 Theory.hide_types.  Also note that former
  5437 Theory.hide_classes/types/consts are now
  5438 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5439 internalize their arguments!  INCOMPATIBILITY.
  5440 
  5441 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5442 datatype thmref (with constructors Name and NameSelection) instead of
  5443 plain string -- INCOMPATIBILITY;
  5444 
  5445 * Pure: cases produced by proof methods specify options, where NONE
  5446 means to remove case bindings -- INCOMPATIBILITY in
  5447 (RAW_)METHOD_CASES.
  5448 
  5449 * Pure: the following operations retrieve axioms or theorems from a
  5450 theory node or theory hierarchy, respectively:
  5451 
  5452   Theory.axioms_of: theory -> (string * term) list
  5453   Theory.all_axioms_of: theory -> (string * term) list
  5454   PureThy.thms_of: theory -> (string * thm) list
  5455   PureThy.all_thms_of: theory -> (string * thm) list
  5456 
  5457 * Pure: print_tac now outputs the goal through the trace channel.
  5458 
  5459 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5460 Reference Toplevel.debug (default false) controls detailed printing
  5461 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5462 controls execution profiling -- set to 1 for time and 2 for space
  5463 (both increase the runtime).
  5464 
  5465 * Isar session: The initial use of ROOT.ML is now always timed,
  5466 i.e. the log will show the actual process times, in contrast to the
  5467 elapsed wall-clock time that the outer shell wrapper produces.
  5468 
  5469 * Simplifier: improved handling of bound variables (nameless
  5470 representation, avoid allocating new strings).  Simprocs that invoke
  5471 the Simplifier recursively should use Simplifier.inherit_bounds to
  5472 avoid local name clashes.  Failure to do so produces warnings
  5473 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5474 for further details.
  5475 
  5476 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5477 bindings for all theorems stored within a given theory; this may help
  5478 in porting non-Isar theories to Isar ones, while keeping ML proof
  5479 scripts for the time being.
  5480 
  5481 * ML operator HTML.with_charset specifies the charset begin used for
  5482 generated HTML files.  For example:
  5483 
  5484   HTML.with_charset "utf-8" use_thy "Hebrew";
  5485   HTML.with_charset "utf-8" use_thy "Chinese";
  5486 
  5487 
  5488 *** System ***
  5489 
  5490 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5491 isabelle, isatool etc.).
  5492 
  5493 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5494 isatool doc, isatool mkdir, display_drafts etc.).
  5495 
  5496 * isatool usedir: option -f allows specification of the ML file to be
  5497 used by Isabelle; default is ROOT.ML.
  5498 
  5499 * New isatool version outputs the version identifier of the Isabelle
  5500 distribution being used.
  5501 
  5502 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5503 (containing Boolean satisfiability problems) into Isabelle/HOL
  5504 theories.
  5505 
  5506 
  5507 
  5508 New in Isabelle2004 (April 2004)
  5509 --------------------------------
  5510 
  5511 *** General ***
  5512 
  5513 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5514   Replaces linorder.ML.
  5515 
  5516 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5517   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5518   (\<a>...\<z>), are now considered normal letters, and can therefore
  5519   be used anywhere where an ASCII letter (a...zA...Z) has until
  5520   now. COMPATIBILITY: This obviously changes the parsing of some
  5521   terms, especially where a symbol has been used as a binder, say
  5522   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5523   as an identifier.  Fix it by inserting a space around former
  5524   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5525   existing theory and ML files.
  5526 
  5527 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5528 
  5529 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5530   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5531   a normal (but invisible) letter. For multiple letter subscripts repeat
  5532   \<^isub> like this: x\<^isub>1\<^isub>2.
  5533 
  5534 * Pure: There are now sub-/superscripts that can span more than one
  5535   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5536   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5537   superscript. The new control characters are not identifier parts.
  5538 
  5539 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5540   content of "..." to the latex file instead of \isacntrl... . The "..."
  5541   may consist of any printable characters excluding the end bracket >.
  5542 
  5543 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5544   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5545   declare constants "final", which prevents their being given a definition
  5546   later.  It is useful for constants whose behaviour is fixed axiomatically
  5547   rather than definitionally, such as the meta-logic connectives.
  5548 
  5549 * Pure: 'instance' now handles general arities with general sorts
  5550   (i.e. intersections of classes),
  5551 
  5552 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5553   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5554   It can be changed to alter the colors/layout of generated pages.
  5555 
  5556 
  5557 *** Isar ***
  5558 
  5559 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5560   cut_tac, subgoal_tac and thin_tac:
  5561   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5562     locales are no longer forced to write Isar proof scripts.
  5563     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5564     emulations.
  5565   - INCOMPATIBILITY: names of variables to be instantiated may no
  5566     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5567     This is consistent with the instantiation attribute "where".
  5568 
  5569 * Attributes "where" and "of":
  5570   - Now take type variables of instantiated theorem into account when reading
  5571     the instantiation string.  This fixes a bug that caused instantiated
  5572     theorems to have too special types in some circumstances.
  5573   - "where" permits explicit instantiations of type variables.
  5574 
  5575 * Calculation commands "moreover" and "also" no longer interfere with
  5576   current facts ("this"), admitting arbitrary combinations with "then"
  5577   and derived forms.
  5578 
  5579 * Locales:
  5580   - Goal statements involving the context element "includes" no longer
  5581     generate theorems with internal delta predicates (those ending on
  5582     "_axioms") in the premise.
  5583     Resolve particular premise with <locale>.intro to obtain old form.
  5584   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5585     specification and "includes" elements in goal statement.
  5586   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5587     [intro?] and [elim?] (respectively) by default.
  5588   - Experimental command for instantiation of locales in proof contexts:
  5589         instantiate <label>[<attrs>]: <loc>
  5590     Instantiates locale <loc> and adds all its theorems to the current context
  5591     taking into account their attributes.  Label and attrs are optional
  5592     modifiers, like in theorem declarations.  If present, names of
  5593     instantiated theorems are qualified with <label>, and the attributes
  5594     <attrs> are applied after any attributes these theorems might have already.
  5595       If the locale has assumptions, a chained fact of the form
  5596     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5597     are derived.  The command does not support old-style locales declared
  5598     with "locale (open)".
  5599       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5600 
  5601 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5602   (Isar) contexts.
  5603 
  5604 
  5605 *** HOL ***
  5606 
  5607 * Proof import: new image HOL4 contains the imported library from
  5608   the HOL4 system with about 2500 theorems. It is imported by
  5609   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5610   can be used like any other Isabelle image.  See
  5611   HOL/Import/HOL/README for more information.
  5612 
  5613 * Simplifier:
  5614   - Much improved handling of linear and partial orders.
  5615     Reasoners for linear and partial orders are set up for type classes
  5616     "linorder" and "order" respectively, and are added to the default simpset
  5617     as solvers.  This means that the simplifier can build transitivity chains
  5618     to solve goals from the assumptions.
  5619   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5620     of blast or auto after simplification become unnecessary because the goal
  5621     is solved by simplification already.
  5622 
  5623 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5624     all proved in axiomatic type classes for semirings, rings and fields.
  5625 
  5626 * Numerics:
  5627   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5628     now formalized using the Ring_and_Field theory mentioned above.
  5629   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5630     than before, because now they are set up once in a generic manner.
  5631   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5632     Look for the general versions in Ring_and_Field (and Power if they concern
  5633     exponentiation).
  5634 
  5635 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5636 
  5637 * Records:
  5638   - Record types are now by default printed with their type abbreviation
  5639     instead of the list of all field types. This can be configured via
  5640     the reference "print_record_type_abbr".
  5641   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5642     (not enabled by default).
  5643   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5644     EX x. x = sel r to True (not enabled by default).
  5645   - Tactic "record_split_simp_tac" to split and simplify records added.
  5646 
  5647 * 'specification' command added, allowing for definition by
  5648   specification.  There is also an 'ax_specification' command that
  5649   introduces the new constants axiomatically.
  5650 
  5651 * arith(_tac) is now able to generate counterexamples for reals as well.
  5652 
  5653 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5654 
  5655 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5656   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5657 
  5658 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5659   matrix theory to linear programming.
  5660 
  5661 * Unions and Intersections:
  5662   The latex output syntax of UN and INT has been changed
  5663   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5664   i.e. the index formulae has become a subscript.
  5665   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5666 
  5667 * Unions and Intersections over Intervals:
  5668   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5669   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5670   like in normal math, and corresponding versions for < and for intersection.
  5671 
  5672 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5673   lexicographic dictonary ordering has been added as "lexord".
  5674 
  5675 * ML: the legacy theory structures Int and List have been removed. They had
  5676   conflicted with ML Basis Library structures having the same names.
  5677 
  5678 * 'refute' command added to search for (finite) countermodels.  Only works
  5679   for a fragment of HOL.  The installation of an external SAT solver is
  5680   highly recommended.  See "HOL/Refute.thy" for details.
  5681 
  5682 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5683   formulae under an assignment of free variables to random values.
  5684   In contrast to 'refute', it can deal with inductive datatypes,
  5685   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5686   for examples.
  5687 
  5688 
  5689 *** HOLCF ***
  5690 
  5691 * Streams now come with concatenation and are part of the HOLCF image
  5692 
  5693 
  5694 
  5695 New in Isabelle2003 (May 2003)
  5696 ------------------------------
  5697 
  5698 *** General ***
  5699 
  5700 * Provers/simplifier:
  5701 
  5702   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5703     Assumptions are now subject to complete mutual simplification,
  5704     not just from left to right. The simplifier now preserves
  5705     the order of assumptions.
  5706 
  5707     Potential INCOMPATIBILITY:
  5708 
  5709     -- simp sometimes diverges where the old version did
  5710        not, e.g. invoking simp on the goal
  5711 
  5712         [| P (f x); y = x; f x = f y |] ==> Q
  5713 
  5714        now gives rise to the infinite reduction sequence
  5715 
  5716         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5717 
  5718        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5719        kind of problem.
  5720 
  5721     -- Tactics combining classical reasoner and simplification (such as auto)
  5722        are also affected by this change, because many of them rely on
  5723        simp. They may sometimes diverge as well or yield a different numbers
  5724        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5725        in case of problems. Sometimes subsequent calls to the classical
  5726        reasoner will fail because a preceeding call to the simplifier too
  5727        eagerly simplified the goal, e.g. deleted redundant premises.
  5728 
  5729   - The simplifier trace now shows the names of the applied rewrite rules
  5730 
  5731   - You can limit the number of recursive invocations of the simplifier
  5732     during conditional rewriting (where the simplifie tries to solve the
  5733     conditions before applying the rewrite rule):
  5734     ML "simp_depth_limit := n"
  5735     where n is an integer. Thus you can force termination where previously
  5736     the simplifier would diverge.
  5737 
  5738   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5739 
  5740   - No longer aborts on failed congruence proof.  Instead, the
  5741     congruence is ignored.
  5742 
  5743 * Pure: New generic framework for extracting programs from constructive
  5744   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5745   as HOL/Extraction for some case studies.
  5746 
  5747 * Pure: The main goal of the proof state is no longer shown by default, only
  5748 the subgoals. This behaviour is controlled by a new flag.
  5749    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5750 (ML: Proof.show_main_goal).
  5751 
  5752 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5753 rules whose conclusion matches subgoal 1:
  5754       PG menu: Isabelle/Isar -> Show me -> matching rules
  5755 The rules are ordered by how closely they match the subgoal.
  5756 In particular, rules that solve a subgoal outright are displayed first
  5757 (or rather last, the way they are printed).
  5758 (ML: ProofGeneral.print_intros())
  5759 
  5760 * Pure: New flag trace_unify_fail causes unification to print
  5761 diagnostic information (PG: in trace buffer) when it fails. This is
  5762 useful for figuring out why single step proofs like rule, erule or
  5763 assumption failed.
  5764 
  5765 * Pure: Locale specifications now produce predicate definitions
  5766 according to the body of text (covering assumptions modulo local
  5767 definitions); predicate "loc_axioms" covers newly introduced text,
  5768 while "loc" is cumulative wrt. all included locale expressions; the
  5769 latter view is presented only on export into the global theory
  5770 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5771 on the old view without predicates;
  5772 
  5773 * Pure: predefined locales "var" and "struct" are useful for sharing
  5774 parameters (as in CASL, for example); just specify something like
  5775 ``var x + var y + struct M'' as import;
  5776 
  5777 * Pure: improved thms_containing: proper indexing of facts instead of
  5778 raw theorems; check validity of results wrt. current name space;
  5779 include local facts of proof configuration (also covers active
  5780 locales), cover fixed variables in index; may use "_" in term
  5781 specification; an optional limit for the number of printed facts may
  5782 be given (the default is 40);
  5783 
  5784 * Pure: disallow duplicate fact bindings within new-style theory files
  5785 (batch-mode only);
  5786 
  5787 * Provers: improved induct method: assumptions introduced by case
  5788 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5789 the goal statement); "foo" still refers to all facts collectively;
  5790 
  5791 * Provers: the function blast.overloaded has been removed: all constants
  5792 are regarded as potentially overloaded, which improves robustness in exchange
  5793 for slight decrease in efficiency;
  5794 
  5795 * Provers/linorder: New generic prover for transitivity reasoning over
  5796 linear orders.  Note: this prover is not efficient!
  5797 
  5798 * Isar: preview of problems to finish 'show' now produce an error
  5799 rather than just a warning (in interactive mode);
  5800 
  5801 
  5802 *** HOL ***
  5803 
  5804 * arith(_tac)
  5805 
  5806  - Produces a counter example if it cannot prove a goal.
  5807    Note that the counter example may be spurious if the goal is not a formula
  5808    of quantifier-free linear arithmetic.
  5809    In ProofGeneral the counter example appears in the trace buffer.
  5810 
  5811  - Knows about div k and mod k where k is a numeral of type nat or int.
  5812 
  5813  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5814    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5815    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5816 
  5817 * simp's arithmetic capabilities have been enhanced a bit: it now
  5818 takes ~= in premises into account (by performing a case split);
  5819 
  5820 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5821 are distributed over a sum of terms;
  5822 
  5823 * New tactic "trans_tac" and method "trans" instantiate
  5824 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5825 "<=", "<" and "=").
  5826 
  5827 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5828 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5829 
  5830 * 'typedef' command has new option "open" to suppress the set
  5831 definition;
  5832 
  5833 * functions Min and Max on finite sets have been introduced (theory
  5834 Finite_Set);
  5835 
  5836 * attribute [symmetric] now works for relations as well; it turns
  5837 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5838 
  5839 * induct over a !!-quantified statement (say !!x1..xn):
  5840   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5841 
  5842 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5843 %x. None. Warning: empty_def now refers to the previously hidden definition
  5844 of the empty set.
  5845 
  5846 * Algebra: formalization of classical algebra.  Intended as base for
  5847 any algebraic development in Isabelle.  Currently covers group theory
  5848 (up to Sylow's theorem) and ring theory (Universal Property of
  5849 Univariate Polynomials).  Contributions welcome;
  5850 
  5851 * GroupTheory: deleted, since its material has been moved to Algebra;
  5852 
  5853 * Complex: new directory of the complex numbers with numeric constants,
  5854 nonstandard complex numbers, and some complex analysis, standard and
  5855 nonstandard (Jacques Fleuriot);
  5856 
  5857 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  5858 
  5859 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  5860 Fleuriot);
  5861 
  5862 * Real/HahnBanach: updated and adapted to locales;
  5863 
  5864 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  5865 Gray and Kramer);
  5866 
  5867 * UNITY: added the Meier-Sanders theory of progress sets;
  5868 
  5869 * MicroJava: bytecode verifier and lightweight bytecode verifier
  5870 as abstract algorithms, instantiated to the JVM;
  5871 
  5872 * Bali: Java source language formalization. Type system, operational
  5873 semantics, axiomatic semantics. Supported language features:
  5874 classes, interfaces, objects,virtual methods, static methods,
  5875 static/instance fields, arrays, access modifiers, definite
  5876 assignment, exceptions.
  5877 
  5878 
  5879 *** ZF ***
  5880 
  5881 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  5882 universe, etc.);
  5883 
  5884 * Main ZF: virtually all theories converted to new-style format;
  5885 
  5886 
  5887 *** ML ***
  5888 
  5889 * Pure: Tactic.prove provides sane interface for internal proofs;
  5890 omits the infamous "standard" operation, so this is more appropriate
  5891 than prove_goalw_cterm in many situations (e.g. in simprocs);
  5892 
  5893 * Pure: improved error reporting of simprocs;
  5894 
  5895 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  5896 up simprocs;
  5897 
  5898 
  5899 *** Document preparation ***
  5900 
  5901 * uses \par instead of \\ for line breaks in theory text. This may
  5902 shift some page breaks in large documents. To get the old behaviour
  5903 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  5904 
  5905 * minimized dependencies of isabelle.sty and isabellesym.sty on
  5906 other packages
  5907 
  5908 * \<euro> now needs package babel/greek instead of marvosym (which
  5909 broke \Rightarrow)
  5910 
  5911 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  5912 textcomp package)
  5913 
  5914 
  5915 
  5916 New in Isabelle2002 (March 2002)
  5917 --------------------------------
  5918 
  5919 *** Document preparation ***
  5920 
  5921 * greatly simplified document preparation setup, including more
  5922 graceful interpretation of isatool usedir -i/-d/-D options, and more
  5923 instructive isatool mkdir; users should basically be able to get
  5924 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  5925 users may run a separate document processing stage manually like this:
  5926 "isatool usedir -D output HOL Test && isatool document Test/output";
  5927 
  5928 * theory dependency graph may now be incorporated into documents;
  5929 isatool usedir -g true will produce session_graph.eps/.pdf for use
  5930 with \includegraphics of LaTeX;
  5931 
  5932 * proper spacing of consecutive markup elements, especially text
  5933 blocks after section headings;
  5934 
  5935 * support bold style (for single symbols only), input syntax is like
  5936 this: "\<^bold>\<alpha>" or "\<^bold>A";
  5937 
  5938 * \<bullet> is now output as bold \cdot by default, which looks much
  5939 better in printed text;
  5940 
  5941 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  5942 note that these symbols are currently unavailable in Proof General /
  5943 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  5944 
  5945 * isatool latex no longer depends on changed TEXINPUTS, instead
  5946 isatool document copies the Isabelle style files to the target
  5947 location;
  5948 
  5949 
  5950 *** Isar ***
  5951 
  5952 * Pure/Provers: improved proof by cases and induction;
  5953   - 'case' command admits impromptu naming of parameters (such as
  5954     "case (Suc n)");
  5955   - 'induct' method divinates rule instantiation from the inductive
  5956     claim; no longer requires excessive ?P bindings for proper
  5957     instantiation of cases;
  5958   - 'induct' method properly enumerates all possibilities of set/type
  5959     rules; as a consequence facts may be also passed through *type*
  5960     rules without further ado;
  5961   - 'induct' method now derives symbolic cases from the *rulified*
  5962     rule (before it used to rulify cases stemming from the internal
  5963     atomized version); this means that the context of a non-atomic
  5964     statement becomes is included in the hypothesis, avoiding the
  5965     slightly cumbersome show "PROP ?case" form;
  5966   - 'induct' may now use elim-style induction rules without chaining
  5967     facts, using ``missing'' premises from the goal state; this allows
  5968     rules stemming from inductive sets to be applied in unstructured
  5969     scripts, while still benefitting from proper handling of non-atomic
  5970     statements; NB: major inductive premises need to be put first, all
  5971     the rest of the goal is passed through the induction;
  5972   - 'induct' proper support for mutual induction involving non-atomic
  5973     rule statements (uses the new concept of simultaneous goals, see
  5974     below);
  5975   - append all possible rule selections, but only use the first
  5976     success (no backtracking);
  5977   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  5978   - undeclared rule case names default to numbers 1, 2, 3, ...;
  5979   - added 'print_induct_rules' (covered by help item in recent Proof
  5980     General versions);
  5981   - moved induct/cases attributes to Pure, methods to Provers;
  5982   - generic method setup instantiated for FOL and HOL;
  5983 
  5984 * Pure: support multiple simultaneous goal statements, for example
  5985 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  5986 meta-level mechanism, this acts as if several individual goals had
  5987 been stated separately; in particular common proof methods need to be
  5988 repeated in order to cover all claims; note that a single elimination
  5989 step is *not* sufficient to establish the two conjunctions, so this
  5990 fails:
  5991 
  5992   assume "A & B" then have A and B ..   (*".." fails*)
  5993 
  5994 better use "obtain" in situations as above; alternative refer to
  5995 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  5996 
  5997 * Pure: proper integration with ``locales''; unlike the original
  5998 version by Florian Kammller, Isar locales package high-level proof
  5999 contexts rather than raw logical ones (e.g. we admit to include
  6000 attributes everywhere); operations on locales include merge and
  6001 rename; support for implicit arguments (``structures''); simultaneous
  6002 type-inference over imports and text; see also HOL/ex/Locales.thy for
  6003 some examples;
  6004 
  6005 * Pure: the following commands have been ``localized'', supporting a
  6006 target locale specification "(in name)": 'lemma', 'theorem',
  6007 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  6008 stored both within the locale and at the theory level (exported and
  6009 qualified by the locale name);
  6010 
  6011 * Pure: theory goals may now be specified in ``long'' form, with
  6012 ad-hoc contexts consisting of arbitrary locale elements. for example
  6013 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  6014 definitions may be given, too); the result is a meta-level rule with
  6015 the context elements being discharged in the obvious way;
  6016 
  6017 * Pure: new proof command 'using' allows to augment currently used
  6018 facts after a goal statement ('using' is syntactically analogous to
  6019 'apply', but acts on the goal's facts only); this allows chained facts
  6020 to be separated into parts given before and after a claim, as in
  6021 ``from a and b have C using d and e <proof>'';
  6022 
  6023 * Pure: renamed "antecedent" case to "rule_context";
  6024 
  6025 * Pure: new 'judgment' command records explicit information about the
  6026 object-logic embedding (used by several tools internally); no longer
  6027 use hard-wired "Trueprop";
  6028 
  6029 * Pure: added 'corollary' command;
  6030 
  6031 * Pure: fixed 'token_translation' command;
  6032 
  6033 * Pure: removed obsolete 'exported' attribute;
  6034 
  6035 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  6036 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  6037 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  6038 
  6039 * Pure: method 'atomize' presents local goal premises as object-level
  6040 statements (atomic meta-level propositions); setup controlled via
  6041 rewrite rules declarations of 'atomize' attribute; example
  6042 application: 'induct' method with proper rule statements in improper
  6043 proof *scripts*;
  6044 
  6045 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  6046 now consider the syntactic context of assumptions, giving a better
  6047 chance to get type-inference of the arguments right (this is
  6048 especially important for locales);
  6049 
  6050 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  6051 mode;
  6052 
  6053 * Pure/obtain: the formal conclusion "thesis", being marked as
  6054 ``internal'', may no longer be reference directly in the text;
  6055 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  6056 situations;
  6057 
  6058 * Pure: generic 'sym' attribute which declares a rule both as pure
  6059 'elim?' and for the 'symmetric' operation;
  6060 
  6061 * Pure: marginal comments ``--'' may now occur just anywhere in the
  6062 text; the fixed correlation with particular command syntax has been
  6063 discontinued;
  6064 
  6065 * Pure: new method 'rules' is particularly well-suited for proof
  6066 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  6067 but often produces more compact proof terms with less detours;
  6068 
  6069 * Pure/Provers/classical: simplified integration with pure rule
  6070 attributes and methods; the classical "intro?/elim?/dest?"
  6071 declarations coincide with the pure ones; the "rule" method no longer
  6072 includes classically swapped intros; "intro" and "elim" methods no
  6073 longer pick rules from the context; also got rid of ML declarations
  6074 AddXIs/AddXEs/AddXDs; all of this has some potential for
  6075 INCOMPATIBILITY;
  6076 
  6077 * Provers/classical: attribute 'swapped' produces classical inversions
  6078 of introduction rules;
  6079 
  6080 * Provers/simplifier: 'simplified' attribute may refer to explicit
  6081 rules instead of full simplifier context; 'iff' attribute handles
  6082 conditional rules;
  6083 
  6084 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  6085 
  6086 * HOL: 'recdef' now fails on unfinished automated proofs, use
  6087 "(permissive)" option to recover old behavior;
  6088 
  6089 * HOL: 'inductive' no longer features separate (collective) attributes
  6090 for 'intros' (was found too confusing);
  6091 
  6092 * HOL: properly declared induction rules less_induct and
  6093 wf_induct_rule;
  6094 
  6095 
  6096 *** HOL ***
  6097 
  6098 * HOL: moved over to sane numeral syntax; the new policy is as
  6099 follows:
  6100 
  6101   - 0 and 1 are polymorphic constants, which are defined on any
  6102   numeric type (nat, int, real etc.);
  6103 
  6104   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  6105   binary representation internally;
  6106 
  6107   - type nat has special constructor Suc, and generally prefers Suc 0
  6108   over 1::nat and Suc (Suc 0) over 2::nat;
  6109 
  6110 This change may cause significant problems of INCOMPATIBILITY; here
  6111 are some hints on converting existing sources:
  6112 
  6113   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  6114   entities, so expressions involving "-" (unary or binary minus) need
  6115   to be spaced properly;
  6116 
  6117   - existing occurrences of "1" may need to be constraint "1::nat" or
  6118   even replaced by Suc 0; similar for old "2";
  6119 
  6120   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  6121 
  6122   - remove all special provisions on numerals in proofs;
  6123 
  6124 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  6125 representation (depends on bin_arith_simps in the default context);
  6126 
  6127 * HOL: symbolic syntax for x^2 (numeral 2);
  6128 
  6129 * HOL: the class of all HOL types is now called "type" rather than
  6130 "term"; INCOMPATIBILITY, need to adapt references to this type class
  6131 in axclass/classes, instance/arities, and (usually rare) occurrences
  6132 in typings (of consts etc.); internally the class is called
  6133 "HOL.type", ML programs should refer to HOLogic.typeS;
  6134 
  6135 * HOL/record package improvements:
  6136   - new derived operations "fields" to build a partial record section,
  6137     "extend" to promote a fixed record to a record scheme, and
  6138     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  6139     declared as simp by default;
  6140   - shared operations ("more", "fields", etc.) now need to be always
  6141     qualified) --- potential INCOMPATIBILITY;
  6142   - removed "make_scheme" operations (use "make" with "extend") --
  6143     INCOMPATIBILITY;
  6144   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  6145   - provides cases/induct rules for use with corresponding Isar
  6146     methods (for concrete records, record schemes, concrete more
  6147     parts, and schematic more parts -- in that order);
  6148   - internal definitions directly based on a light-weight abstract
  6149     theory of product types over typedef rather than datatype;
  6150 
  6151 * HOL: generic code generator for generating executable ML code from
  6152 specifications; specific support for HOL constructs such as inductive
  6153 datatypes and sets, as well as recursive functions; can be invoked
  6154 via 'generate_code' theory section;
  6155 
  6156 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  6157 
  6158 * HOL: consolidated and renamed several theories.  In particular:
  6159         Ord.thy has been absorbed into HOL.thy
  6160         String.thy has been absorbed into List.thy
  6161 
  6162 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  6163 (beware of argument permutation!);
  6164 
  6165 * HOL: linorder_less_split superseded by linorder_cases;
  6166 
  6167 * HOL/List: "nodups" renamed to "distinct";
  6168 
  6169 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  6170 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  6171   - Ex_def has changed, now need to use some_eq_ex
  6172 
  6173 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  6174 in this (rare) case use:
  6175 
  6176   delSWrapper "split_all_tac"
  6177   addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
  6178 
  6179 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
  6180 MAY FAIL;
  6181 
  6182 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
  6183 Isabelle's type classes, ^ on functions and relations has too general
  6184 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be
  6185 necessary to attach explicit type constraints;
  6186 
  6187 * HOL/Relation: the prefix name of the infix "O" has been changed from
  6188 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been
  6189 renamed accordingly (eg "compI" -> "rel_compI").
  6190 
  6191 * HOL: syntax translations now work properly with numerals and records
  6192 expressions;
  6193 
  6194 * HOL: bounded abstraction now uses syntax "%" / "\<lambda>" instead
  6195 of "lam" -- INCOMPATIBILITY;
  6196 
  6197 * HOL: got rid of some global declarations (potential INCOMPATIBILITY
  6198 for ML tools): const "()" renamed "Product_Type.Unity", type "unit"
  6199 renamed "Product_Type.unit";
  6200 
  6201 * HOL: renamed rtrancl_into_rtrancl2 to converse_rtrancl_into_rtrancl
  6202 
  6203 * HOL: removed obsolete theorem "optionE" (use "option.exhaust", or
  6204 the "cases" method);
  6205 
  6206 * HOL/GroupTheory: group theory examples including Sylow's theorem (by
  6207 Florian Kammller);
  6208 
  6209 * HOL/IMP: updated and converted to new-style theory format; several
  6210 parts turned into readable document, with proper Isar proof texts and
  6211 some explanations (by Gerwin Klein);
  6212 
  6213 * HOL-Real: added Complex_Numbers (by Gertrud Bauer);
  6214 
  6215 * HOL-Hyperreal is now a logic image;
  6216 
  6217 
  6218 *** HOLCF ***
  6219 
  6220 * Isar: consts/constdefs supports mixfix syntax for continuous
  6221 operations;
  6222 
  6223 * Isar: domain package adapted to new-style theory format, e.g. see
  6224 HOLCF/ex/Dnat.thy;
  6225 
  6226 * theory Lift: proper use of rep_datatype lift instead of ML hacks --
  6227 potential INCOMPATIBILITY; now use plain induct_tac instead of former
  6228 lift.induct_tac, always use UU instead of Undef;
  6229 
  6230 * HOLCF/IMP: updated and converted to new-style theory;
  6231 
  6232 
  6233 *** ZF ***
  6234 
  6235 * Isar: proper integration of logic-specific tools and packages,
  6236 including theory commands '(co)inductive', '(co)datatype',
  6237 'rep_datatype', 'inductive_cases', as well as methods 'ind_cases',
  6238 'induct_tac', 'case_tac', and 'typecheck' (with attribute 'TC');
  6239 
  6240 * theory Main no longer includes AC; for the Axiom of Choice, base
  6241 your theory on Main_ZFC;
  6242 
  6243 * the integer library now covers quotients and remainders, with many
  6244 laws relating division to addition, multiplication, etc.;
  6245 
  6246 * ZF/UNITY: Chandy and Misra's UNITY is now available in ZF, giving a
  6247 typeless version of the formalism;
  6248 
  6249 * ZF/AC, Coind, IMP, Resid: updated and converted to new-style theory
  6250 format;
  6251 
  6252 * ZF/Induct: new directory for examples of inductive definitions,
  6253 including theory Multiset for multiset orderings; converted to
  6254 new-style theory format;
  6255 
  6256 * ZF: many new theorems about lists, ordinals, etc.;
  6257 
  6258 
  6259 *** General ***
  6260 
  6261 * Pure/kernel: meta-level proof terms (by Stefan Berghofer); reference
  6262 variable proof controls level of detail: 0 = no proofs (only oracle
  6263 dependencies), 1 = lemma dependencies, 2 = compact proof terms; see
  6264 also ref manual for further ML interfaces;
  6265 
  6266 * Pure/axclass: removed obsolete ML interface
  6267 goal_subclass/goal_arity;
  6268 
  6269 * Pure/syntax: new token syntax "num" for plain numerals (without "#"
  6270 of "xnum"); potential INCOMPATIBILITY, since -0, -1 etc. are now
  6271 separate tokens, so expressions involving minus need to be spaced
  6272 properly;
  6273 
  6274 * Pure/syntax: support non-oriented infixes, using keyword "infix"
  6275 rather than "infixl" or "infixr";
  6276 
  6277 * Pure/syntax: concrete syntax for dummy type variables admits genuine
  6278 sort constraint specifications in type inference; e.g. "x::_::foo"
  6279 ensures that the type of "x" is of sort "foo" (but not necessarily a
  6280 type variable);
  6281 
  6282 * Pure/syntax: print modes "type_brackets" and "no_type_brackets"
  6283 control output of nested => (types); the default behavior is
  6284 "type_brackets";
  6285 
  6286 * Pure/syntax: builtin parse translation for "_constify" turns valued
  6287 tokens into AST constants;
  6288 
  6289 * Pure/syntax: prefer later declarations of translations and print
  6290 translation functions; potential INCOMPATIBILITY: need to reverse
  6291 multiple declarations for same syntax element constant;
  6292 
  6293 * Pure/show_hyps reset by default (in accordance to existing Isar
  6294 practice);
  6295 
  6296 * Provers/classical: renamed addaltern to addafter, addSaltern to
  6297 addSafter;
  6298 
  6299 * Provers/clasimp: ``iff'' declarations now handle conditional rules
  6300 as well;
  6301 
  6302 * system: tested support for MacOS X; should be able to get Isabelle +
  6303 Proof General to work in a plain Terminal after installing Poly/ML
  6304 (e.g. from the Isabelle distribution area) and GNU bash alone
  6305 (e.g. from http://www.apple.com); full X11, XEmacs and X-Symbol
  6306 support requires further installations, e.g. from
  6307 http://fink.sourceforge.net/);
  6308 
  6309 * system: support Poly/ML 4.1.1 (able to manage larger heaps);
  6310 
  6311 * system: reduced base memory usage by Poly/ML (approx. 20 MB instead
  6312 of 40 MB), cf. ML_OPTIONS;
  6313 
  6314 * system: Proof General keywords specification is now part of the
  6315 Isabelle distribution (see etc/isar-keywords.el);
  6316 
  6317 * system: support for persistent Proof General sessions (refrain from
  6318 outdating all loaded theories on startup); user may create writable
  6319 logic images like this: ``isabelle -q HOL Test'';
  6320 
  6321 * system: smart selection of Isabelle process versus Isabelle
  6322 interface, accommodates case-insensitive file systems (e.g. HFS+); may
  6323 run both "isabelle" and "Isabelle" even if file names are badly
  6324 damaged (executable inspects the case of the first letter of its own
  6325 name); added separate "isabelle-process" and "isabelle-interface";
  6326 
  6327 * system: refrain from any attempt at filtering input streams; no
  6328 longer support ``8bit'' encoding of old isabelle font, instead proper
  6329 iso-latin characters may now be used; the related isatools
  6330 "symbolinput" and "nonascii" have disappeared as well;
  6331 
  6332 * system: removed old "xterm" interface (the print modes "xterm" and
  6333 "xterm_color" are still available for direct use in a suitable
  6334 terminal);
  6335 
  6336 
  6337 
  6338 New in Isabelle99-2 (February 2001)
  6339 -----------------------------------
  6340 
  6341 *** Overview of INCOMPATIBILITIES ***
  6342 
  6343 * HOL: please note that theories in the Library and elsewhere often use the
  6344 new-style (Isar) format; to refer to their theorems in an ML script you must
  6345 bind them to ML identifers by e.g.      val thm_name = thm "thm_name";
  6346 
  6347 * HOL: inductive package no longer splits induction rule aggressively,
  6348 but only as far as specified by the introductions given; the old
  6349 format may be recovered via ML function complete_split_rule or attribute
  6350 'split_rule (complete)';
  6351 
  6352 * HOL: induct renamed to lfp_induct, lfp_Tarski to lfp_unfold,
  6353 gfp_Tarski to gfp_unfold;
  6354 
  6355 * HOL: contrapos, contrapos2 renamed to contrapos_nn, contrapos_pp;
  6356 
  6357 * HOL: infix "dvd" now has priority 50 rather than 70 (because it is a
  6358 relation); infix "^^" has been renamed "``"; infix "``" has been
  6359 renamed "`"; "univalent" has been renamed "single_valued";
  6360 
  6361 * HOL/Real: "rinv" and "hrinv" replaced by overloaded "inverse"
  6362 operation;
  6363 
  6364 * HOLCF: infix "`" has been renamed "$"; the symbol syntax is \<cdot>;
  6365 
  6366 * Isar: 'obtain' no longer declares "that" fact as simp/intro;
  6367 
  6368 * Isar/HOL: method 'induct' now handles non-atomic goals; as a
  6369 consequence, it is no longer monotonic wrt. the local goal context
  6370 (which is now passed through the inductive cases);
  6371 
  6372 * Document preparation: renamed standard symbols \<ll> to \<lless> and
  6373 \<gg> to \<ggreater>;
  6374 
  6375 
  6376 *** Document preparation ***
  6377 
  6378 * \isabellestyle{NAME} selects version of Isabelle output (currently
  6379 available: are "it" for near math-mode best-style output, "sl" for
  6380 slanted text style, and "tt" for plain type-writer; if no
  6381 \isabellestyle command is given, output is according to slanted
  6382 type-writer);
  6383 
  6384 * support sub/super scripts (for single symbols only), input syntax is
  6385 like this: "A\<^sup>*" or "A\<^sup>\<star>";
  6386 
  6387 * some more standard symbols; see Appendix A of the system manual for
  6388 the complete list of symbols defined in isabellesym.sty;
  6389 
  6390 * improved isabelle style files; more abstract symbol implementation
  6391 (should now use \isamath{...} and \isatext{...} in custom symbol
  6392 definitions);
  6393 
  6394 * antiquotation @{goals} and @{subgoals} for output of *dynamic* goals
  6395 state; Note that presentation of goal states does not conform to
  6396 actual human-readable proof documents.  Please do not include goal
  6397 states into document output unless you really know what you are doing!
  6398 
  6399 * proper indentation of antiquoted output with proportional LaTeX
  6400 fonts;
  6401 
  6402 * no_document ML operator temporarily disables LaTeX document
  6403 generation;
  6404 
  6405 * isatool unsymbolize tunes sources for plain ASCII communication;
  6406 
  6407 
  6408 *** Isar ***
  6409 
  6410 * Pure: Isar now suffers initial goal statements to contain unbound
  6411 schematic variables (this does not conform to actual readable proof
  6412 documents, due to unpredictable outcome and non-compositional proof
  6413 checking); users who know what they are doing may use schematic goals
  6414 for Prolog-style synthesis of proven results;
  6415 
  6416 * Pure: assumption method (an implicit finishing) now handles actual
  6417 rules as well;
  6418 
  6419 * Pure: improved 'obtain' --- moved to Pure, insert "that" into
  6420 initial goal, declare "that" only as Pure intro (only for single
  6421 steps); the "that" rule assumption may now be involved in implicit
  6422 finishing, thus ".." becomes a feasible for trivial obtains;
  6423 
  6424 * Pure: default proof step now includes 'intro_classes'; thus trivial
  6425 instance proofs may be performed by "..";
  6426 
  6427 * Pure: ?thesis / ?this / "..." now work for pure meta-level
  6428 statements as well;
  6429 
  6430 * Pure: more robust selection of calculational rules;
  6431 
  6432 * Pure: the builtin notion of 'finished' goal now includes the ==-refl
  6433 rule (as well as the assumption rule);
  6434 
  6435 * Pure: 'thm_deps' command visualizes dependencies of theorems and
  6436 lemmas, using the graph browser tool;
  6437 
  6438 * Pure: predict failure of "show" in interactive mode;
  6439 
  6440 * Pure: 'thms_containing' now takes actual terms as arguments;
  6441 
  6442 * HOL: improved method 'induct' --- now handles non-atomic goals
  6443 (potential INCOMPATIBILITY); tuned error handling;
  6444 
  6445 * HOL: cases and induct rules now provide explicit hints about the
  6446 number of facts to be consumed (0 for "type" and 1 for "set" rules);
  6447 any remaining facts are inserted into the goal verbatim;
  6448 
  6449 * HOL: local contexts (aka cases) may now contain term bindings as
  6450 well; the 'cases' and 'induct' methods new provide a ?case binding for
  6451 the result to be shown in each case;
  6452 
  6453 * HOL: added 'recdef_tc' command;
  6454 
  6455 * isatool convert assists in eliminating legacy ML scripts;
  6456 
  6457 
  6458 *** HOL ***
  6459 
  6460 * HOL/Library: a collection of generic theories to be used together
  6461 with main HOL; the theory loader path already includes this directory
  6462 by default; the following existing theories have been moved here:
  6463 HOL/Induct/Multiset, HOL/Induct/Acc (as Accessible_Part), HOL/While
  6464 (as While_Combinator), HOL/Lex/Prefix (as List_Prefix);
  6465 
  6466 * HOL/Unix: "Some aspects of Unix file-system security", a typical
  6467 modelling and verification task performed in Isabelle/HOL +
  6468 Isabelle/Isar + Isabelle document preparation (by Markus Wenzel).
  6469 
  6470 * HOL/Algebra: special summation operator SUM no longer exists, it has
  6471 been replaced by setsum; infix 'assoc' now has priority 50 (like
  6472 'dvd'); axiom 'one_not_zero' has been moved from axclass 'ring' to
  6473 'domain', this makes the theory consistent with mathematical
  6474 literature;
  6475 
  6476 * HOL basics: added overloaded operations "inverse" and "divide"
  6477 (infix "/"), syntax for generic "abs" operation, generic summation
  6478 operator \<Sum>;
  6479 
  6480 * HOL/typedef: simplified package, provide more useful rules (see also
  6481 HOL/subset.thy);
  6482 
  6483 * HOL/datatype: induction rule for arbitrarily branching datatypes is
  6484 now expressed as a proper nested rule (old-style tactic scripts may
  6485 require atomize_strip_tac to cope with non-atomic premises);
  6486 
  6487 * HOL: renamed theory "Prod" to "Product_Type", renamed "split" rule
  6488 to "split_conv" (old name still available for compatibility);
  6489 
  6490 * HOL: improved concrete syntax for strings (e.g. allows translation
  6491 rules with string literals);
  6492 
  6493 * HOL-Real-Hyperreal: this extends HOL-Real with the hyperreals
  6494  and Fleuriot's mechanization of analysis, including the transcendental
  6495  functions for the reals;
  6496 
  6497 * HOL/Real, HOL/Hyperreal: improved arithmetic simplification;
  6498 
  6499 
  6500 *** CTT ***
  6501 
  6502 * CTT: x-symbol support for Pi, Sigma, -->, : (membership); note that
  6503 "lam" is displayed as TWO lambda-symbols
  6504 
  6505 * CTT: theory Main now available, containing everything (that is, Bool
  6506 and Arith);
  6507 
  6508 
  6509 *** General ***
  6510 
  6511 * Pure: the Simplifier has been implemented properly as a derived rule
  6512 outside of the actual kernel (at last!); the overall performance
  6513 penalty in practical applications is about 50%, while reliability of
  6514 the Isabelle inference kernel has been greatly improved;
  6515 
  6516 * print modes "brackets" and "no_brackets" control output of nested =>
  6517 (types) and ==> (props); the default behaviour is "brackets";
  6518 
  6519 * Provers: fast_tac (and friends) now handle actual object-logic rules
  6520 as assumptions as well;
  6521 
  6522 * system: support Poly/ML 4.0;
  6523 
  6524 * system: isatool install handles KDE version 1 or 2;
  6525 
  6526 
  6527 
  6528 New in Isabelle99-1 (October 2000)
  6529 ----------------------------------
  6530 
  6531 *** Overview of INCOMPATIBILITIES ***
  6532 
  6533 * HOL: simplification of natural numbers is much changed; to partly
  6534 recover the old behaviour (e.g. to prevent n+n rewriting to #2*n)
  6535 issue the following ML commands:
  6536 
  6537   Delsimprocs Nat_Numeral_Simprocs.cancel_numerals;
  6538   Delsimprocs [Nat_Numeral_Simprocs.combine_numerals];
  6539 
  6540 * HOL: simplification no longer dives into case-expressions; this is
  6541 controlled by "t.weak_case_cong" for each datatype t;
  6542 
  6543 * HOL: nat_less_induct renamed to less_induct;
  6544 
  6545 * HOL: systematic renaming of the SOME (Eps) rules, may use isatool
  6546 fixsome to patch .thy and .ML sources automatically;
  6547 
  6548   select_equality  -> some_equality
  6549   select_eq_Ex     -> some_eq_ex
  6550   selectI2EX       -> someI2_ex
  6551   selectI2         -> someI2
  6552   selectI          -> someI
  6553   select1_equality -> some1_equality
  6554   Eps_sym_eq       -> some_sym_eq_trivial
  6555   Eps_eq           -> some_eq_trivial
  6556 
  6557 * HOL: exhaust_tac on datatypes superceded by new generic case_tac;
  6558 
  6559 * HOL: removed obsolete theorem binding expand_if (refer to split_if
  6560 instead);
  6561 
  6562 * HOL: the recursion equations generated by 'recdef' are now called
  6563 f.simps instead of f.rules;
  6564 
  6565 * HOL: qed_spec_mp now also handles bounded ALL as well;
  6566 
  6567 * HOL: 0 is now overloaded, so the type constraint ":: nat" may
  6568 sometimes be needed;
  6569 
  6570 * HOL: the constant for "f``x" is now "image" rather than "op ``";
  6571 
  6572 * HOL: the constant for "f-``x" is now "vimage" rather than "op -``";
  6573 
  6574 * HOL: the disjoint sum is now "<+>" instead of "Plus"; the cartesian
  6575 product is now "<*>" instead of "Times"; the lexicographic product is
  6576 now "<*lex*>" instead of "**";
  6577 
  6578 * HOL: theory Sexp is now in HOL/Induct examples (it used to be part
  6579 of main HOL, but was unused); better use HOL's datatype package;
  6580 
  6581 * HOL: removed "symbols" syntax for constant "override" of theory Map;
  6582 the old syntax may be recovered as follows:
  6583 
  6584   syntax (symbols)
  6585     override  :: "('a ~=> 'b) => ('a ~=> 'b) => ('a ~=> 'b)"
  6586       (infixl "\\<oplus>" 100)
  6587 
  6588 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  6589 
  6590 * HOL/ML: even fewer consts are declared as global (see theories Ord,
  6591 Lfp, Gfp, WF); this only affects ML packages that refer to const names
  6592 internally;
  6593 
  6594 * HOL and ZF: syntax for quotienting wrt an equivalence relation
  6595 changed from A/r to A//r;
  6596 
  6597 * ZF: new treatment of arithmetic (nat & int) may break some old
  6598 proofs;
  6599 
  6600 * Isar: renamed some attributes (RS -> THEN, simplify -> simplified,
  6601 rulify -> rule_format, elimify -> elim_format, ...);
  6602 
  6603 * Isar/Provers: intro/elim/dest attributes changed; renamed
  6604 intro/intro!/intro!! flags to intro!/intro/intro? (in most cases, one
  6605 should have to change intro!! to intro? only); replaced "delrule" by
  6606 "rule del";
  6607 
  6608 * Isar/HOL: renamed "intrs" to "intros" in inductive definitions;
  6609 
  6610 * Provers: strengthened force_tac by using new first_best_tac;
  6611 
  6612 * LaTeX document preparation: several changes of isabelle.sty (see
  6613 lib/texinputs);
  6614 
  6615 
  6616 *** Document preparation ***
  6617 
  6618 * formal comments (text blocks etc.) in new-style theories may now
  6619 contain antiquotations of thm/prop/term/typ/text to be presented
  6620 according to latex print mode; concrete syntax is like this:
  6621 @{term[show_types] "f(x) = a + x"};
  6622 
  6623 * isatool mkdir provides easy setup of Isabelle session directories,
  6624 including proper document sources;
  6625 
  6626 * generated LaTeX sources are now deleted after successful run
  6627 (isatool document -c); may retain a copy somewhere else via -D option
  6628 of isatool usedir;
  6629 
  6630 * isatool usedir -D now lets isatool latex -o sty update the Isabelle
  6631 style files, achieving self-contained LaTeX sources and simplifying
  6632 LaTeX debugging;
  6633 
  6634 * old-style theories now produce (crude) LaTeX output as well;
  6635 
  6636 * browser info session directories are now self-contained (may be put
  6637 on WWW server seperately); improved graphs of nested sessions; removed
  6638 graph for 'all sessions';
  6639 
  6640 * several improvements in isabelle style files; \isabellestyle{it}
  6641 produces fake math mode output; \isamarkupheader is now \section by
  6642 default; see lib/texinputs/isabelle.sty etc.;
  6643 
  6644 
  6645 *** Isar ***
  6646 
  6647 * Isar/Pure: local results and corresponding term bindings are now
  6648 subject to Hindley-Milner polymorphism (similar to ML); this
  6649 accommodates incremental type-inference very nicely;
  6650 
  6651 * Isar/Pure: new derived language element 'obtain' supports
  6652 generalized existence reasoning;
  6653 
  6654 * Isar/Pure: new calculational elements 'moreover' and 'ultimately'
  6655 support accumulation of results, without applying any rules yet;
  6656 useful to collect intermediate results without explicit name
  6657 references, and for use with transitivity rules with more than 2
  6658 premises;
  6659 
  6660 * Isar/Pure: scalable support for case-analysis type proofs: new
  6661 'case' language element refers to local contexts symbolically, as
  6662 produced by certain proof methods; internally, case names are attached
  6663 to theorems as "tags";
  6664 
  6665 * Isar/Pure: theory command 'hide' removes declarations from
  6666 class/type/const name spaces;
  6667 
  6668 * Isar/Pure: theory command 'defs' supports option "(overloaded)" to
  6669 indicate potential overloading;
  6670 
  6671 * Isar/Pure: changed syntax of local blocks from {{ }} to { };
  6672 
  6673 * Isar/Pure: syntax of sorts made 'inner', i.e. have to write
  6674 "{a,b,c}" instead of {a,b,c};
  6675 
  6676 * Isar/Pure now provides its own version of intro/elim/dest
  6677 attributes; useful for building new logics, but beware of confusion
  6678 with the version in Provers/classical;
  6679 
  6680 * Isar/Pure: the local context of (non-atomic) goals is provided via
  6681 case name 'antecedent';
  6682 
  6683 * Isar/Pure: removed obsolete 'transfer' attribute (transfer of thms
  6684 to the current context is now done automatically);
  6685 
  6686 * Isar/Pure: theory command 'method_setup' provides a simple interface
  6687 for definining proof methods in ML;
  6688 
  6689 * Isar/Provers: intro/elim/dest attributes changed; renamed
  6690 intro/intro!/intro!! flags to intro!/intro/intro? (INCOMPATIBILITY, in
  6691 most cases, one should have to change intro!! to intro? only);
  6692 replaced "delrule" by "rule del";
  6693 
  6694 * Isar/Provers: new 'hypsubst' method, plain 'subst' method and
  6695 'symmetric' attribute (the latter supercedes [RS sym]);
  6696 
  6697 * Isar/Provers: splitter support (via 'split' attribute and 'simp'
  6698 method modifier); 'simp' method: 'only:' modifier removes loopers as
  6699 well (including splits);
  6700 
  6701 * Isar/Provers: Simplifier and Classical methods now support all kind
  6702 of modifiers used in the past, including 'cong', 'iff', etc.
  6703 
  6704 * Isar/Provers: added 'fastsimp' and 'clarsimp' methods (combination
  6705 of Simplifier and Classical reasoner);
  6706 
  6707 * Isar/HOL: new proof method 'cases' and improved version of 'induct'
  6708 now support named cases; major packages (inductive, datatype, primrec,
  6709 recdef) support case names and properly name parameters;
  6710 
  6711 * Isar/HOL: new transitivity rules for substitution in inequalities --
  6712 monotonicity conditions are extracted to be proven at end of
  6713 calculations;
  6714 
  6715 * Isar/HOL: removed 'case_split' thm binding, should use 'cases' proof
  6716 method anyway;
  6717 
  6718 * Isar/HOL: removed old expand_if = split_if; theorems if_splits =
  6719 split_if split_if_asm; datatype package provides theorems foo.splits =
  6720 foo.split foo.split_asm for each datatype;
  6721 
  6722 * Isar/HOL: tuned inductive package, rename "intrs" to "intros"
  6723 (potential INCOMPATIBILITY), emulation of mk_cases feature for proof
  6724 scripts: new 'inductive_cases' command and 'ind_cases' method; (Note:
  6725 use "(cases (simplified))" method in proper proof texts);
  6726 
  6727 * Isar/HOL: added global 'arith_split' attribute for 'arith' method;
  6728 
  6729 * Isar: names of theorems etc. may be natural numbers as well;
  6730 
  6731 * Isar: 'pr' command: optional arguments for goals_limit and
  6732 ProofContext.prems_limit; no longer prints theory contexts, but only
  6733 proof states;
  6734 
  6735 * Isar: diagnostic commands 'pr', 'thm', 'prop', 'term', 'typ' admit
  6736 additional print modes to be specified; e.g. "pr(latex)" will print
  6737 proof state according to the Isabelle LaTeX style;
  6738 
  6739 * Isar: improved support for emulating tactic scripts, including proof
  6740 methods 'rule_tac' etc., 'cut_tac', 'thin_tac', 'subgoal_tac',
  6741 'rename_tac', 'rotate_tac', 'tactic', and 'case_tac' / 'induct_tac'
  6742 (for HOL datatypes);
  6743 
  6744 * Isar: simplified (more robust) goal selection of proof methods: 1st
  6745 goal, all goals, or explicit goal specifier (tactic emulation); thus
  6746 'proof method scripts' have to be in depth-first order;
  6747 
  6748 * Isar: tuned 'let' syntax: replaced 'as' keyword by 'and';
  6749 
  6750 * Isar: removed 'help' command, which hasn't been too helpful anyway;
  6751 should instead use individual commands for printing items
  6752 (print_commands, print_methods etc.);
  6753 
  6754 * Isar: added 'nothing' --- the empty list of theorems;
  6755 
  6756 
  6757 *** HOL ***
  6758 
  6759 * HOL/MicroJava: formalization of a fragment of Java, together with a
  6760 corresponding virtual machine and a specification of its bytecode
  6761 verifier and a lightweight bytecode verifier, including proofs of
  6762 type-safety; by Gerwin Klein, Tobias Nipkow, David von Oheimb, and
  6763 Cornelia Pusch (see also the homepage of project Bali at
  6764 http://isabelle.in.tum.de/Bali/);
  6765 
  6766 * HOL/Algebra: new theory of rings and univariate polynomials, by
  6767 Clemens Ballarin;
  6768 
  6769 * HOL/NumberTheory: fundamental Theorem of Arithmetic, Chinese
  6770 Remainder Theorem, Fermat/Euler Theorem, Wilson's Theorem, by Thomas M
  6771 Rasmussen;
  6772 
  6773 * HOL/Lattice: fundamental concepts of lattice theory and order
  6774 structures, including duals, properties of bounds versus algebraic
  6775 laws, lattice operations versus set-theoretic ones, the Knaster-Tarski
  6776 Theorem for complete lattices etc.; may also serve as a demonstration
  6777 for abstract algebraic reasoning using axiomatic type classes, and
  6778 mathematics-style proof in Isabelle/Isar; by Markus Wenzel;
  6779 
  6780 * HOL/Prolog: a (bare-bones) implementation of Lambda-Prolog, by David
  6781 von Oheimb;
  6782 
  6783 * HOL/IMPP: extension of IMP with local variables and mutually
  6784 recursive procedures, by David von Oheimb;
  6785 
  6786 * HOL/Lambda: converted into new-style theory and document;
  6787 
  6788 * HOL/ex/Multiquote: example of multiple nested quotations and
  6789 anti-quotations -- basically a generalized version of de-Bruijn
  6790 representation; very useful in avoiding lifting of operations;
  6791 
  6792 * HOL/record: added general record equality rule to simpset; fixed
  6793 select-update simplification procedure to handle extended records as
  6794 well; admit "r" as field name;
  6795 
  6796 * HOL: 0 is now overloaded over the new sort "zero", allowing its use with
  6797 other numeric types and also as the identity of groups, rings, etc.;
  6798 
  6799 * HOL: new axclass plus_ac0 for addition with the AC-laws and 0 as identity.
  6800 Types nat and int belong to this axclass;
  6801 
  6802 * HOL: greatly improved simplification involving numerals of type nat, int, real:
  6803    (i + #8 + j) = Suc k simplifies to  #7 + (i + j) = k
  6804    i*j + k + j*#3*i     simplifies to  #4*(i*j) + k
  6805   two terms #m*u and #n*u are replaced by #(m+n)*u
  6806     (where #m, #n and u can implicitly be 1; this is simproc combine_numerals)
  6807   and the term/formula #m*u+x ~~ #n*u+y simplifies simplifies to #(m-n)+x ~~ y
  6808     or x ~~ #(n-m)+y, where ~~ is one of = < <= or - (simproc cancel_numerals);
  6809 
  6810 * HOL: meson_tac is available (previously in ex/meson.ML); it is a
  6811 powerful prover for predicate logic but knows nothing of clasets; see
  6812 ex/mesontest.ML and ex/mesontest2.ML for example applications;
  6813 
  6814 * HOL: new version of "case_tac" subsumes both boolean case split and
  6815 "exhaust_tac" on datatypes; INCOMPATIBILITY: exhaust_tac no longer
  6816 exists, may define val exhaust_tac = case_tac for ad-hoc portability;
  6817 
  6818 * HOL: simplification no longer dives into case-expressions: only the
  6819 selector expression is simplified, but not the remaining arms; to
  6820 enable full simplification of case-expressions for datatype t, you may
  6821 remove t.weak_case_cong from the simpset, either globally (Delcongs
  6822 [thm"t.weak_case_cong"];) or locally (delcongs [...]).
  6823 
  6824 * HOL/recdef: the recursion equations generated by 'recdef' for
  6825 function 'f' are now called f.simps instead of f.rules; if all
  6826 termination conditions are proved automatically, these simplification
  6827 rules are added to the simpset, as in primrec; rules may be named
  6828 individually as well, resulting in a separate list of theorems for
  6829 each equation;
  6830 
  6831 * HOL/While is a new theory that provides a while-combinator. It
  6832 permits the definition of tail-recursive functions without the
  6833 provision of a termination measure. The latter is necessary once the
  6834 invariant proof rule for while is applied.
  6835 
  6836 * HOL: new (overloaded) notation for the set of elements below/above
  6837 some element: {..u}, {..u(}, {l..}, {)l..}. See theory SetInterval.
  6838 
  6839 * HOL: theorems impI, allI, ballI bound as "strip";
  6840 
  6841 * HOL: new tactic induct_thm_tac: thm -> string -> int -> tactic
  6842 induct_tac th "x1 ... xn" expects th to have a conclusion of the form
  6843 P v1 ... vn and abbreviates res_inst_tac [("v1","x1"),...,("vn","xn")] th;
  6844 
  6845 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  6846 
  6847 * HOL: theory Sexp now in HOL/Induct examples (it used to be part of
  6848 main HOL, but was unused);
  6849 
  6850 * HOL: fewer consts declared as global (e.g. have to refer to
  6851 "Lfp.lfp" instead of "lfp" internally; affects ML packages only);
  6852 
  6853 * HOL: tuned AST representation of nested pairs, avoiding bogus output
  6854 in case of overlap with user translations (e.g. judgements over
  6855 tuples); (note that the underlying logical represenation is still
  6856 bogus);
  6857 
  6858 
  6859 *** ZF ***
  6860 
  6861 * ZF: simplification automatically cancels common terms in arithmetic
  6862 expressions over nat and int;
  6863 
  6864 * ZF: new treatment of nat to minimize type-checking: all operators
  6865 coerce their operands to a natural number using the function natify,
  6866 making the algebraic laws unconditional;
  6867 
  6868 * ZF: as above, for int: operators coerce their operands to an integer
  6869 using the function intify;
  6870 
  6871 * ZF: the integer library now contains many of the usual laws for the
  6872 orderings, including $<=, and monotonicity laws for $+ and $*;
  6873 
  6874 * ZF: new example ZF/ex/NatSum to demonstrate integer arithmetic
  6875 simplification;
  6876 
  6877 * FOL and ZF: AddIffs now available, giving theorems of the form P<->Q
  6878 to the simplifier and classical reasoner simultaneously;
  6879 
  6880 
  6881 *** General ***
  6882 
  6883 * Provers: blast_tac now handles actual object-logic rules as
  6884 assumptions; note that auto_tac uses blast_tac internally as well;
  6885 
  6886 * Provers: new functions rulify/rulify_no_asm: thm -> thm for turning
  6887 outer -->/All/Ball into ==>/!!; qed_spec_mp now uses rulify_no_asm;
  6888 
  6889 * Provers: delrules now handles destruct rules as well (no longer need
  6890 explicit make_elim);
  6891 
  6892 * Provers: Blast_tac now warns of and ignores "weak elimination rules" e.g.
  6893   [| inj ?f;          ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  6894 use instead the strong form,
  6895   [| inj ?f; ~ ?W ==> ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  6896 in HOL, FOL and ZF the function cla_make_elim will create such rules
  6897 from destruct-rules;
  6898 
  6899 * Provers: Simplifier.easy_setup provides a fast path to basic
  6900 Simplifier setup for new object-logics;
  6901 
  6902 * Pure: AST translation rules no longer require constant head on LHS;
  6903 
  6904 * Pure: improved name spaces: ambiguous output is qualified; support
  6905 for hiding of names;
  6906 
  6907 * system: smart setup of canonical ML_HOME, ISABELLE_INTERFACE, and
  6908 XSYMBOL_HOME; no longer need to do manual configuration in most
  6909 situations;
  6910 
  6911 * system: compression of ML heaps images may now be controlled via -c
  6912 option of isabelle and isatool usedir (currently only observed by
  6913 Poly/ML);
  6914 
  6915 * system: isatool installfonts may handle X-Symbol fonts as well (very
  6916 useful for remote X11);
  6917 
  6918 * system: provide TAGS file for Isabelle sources;
  6919 
  6920 * ML: infix 'OF' is a version of 'MRS' with more appropriate argument
  6921 order;
  6922 
  6923 * ML: renamed flags Syntax.trace_norm_ast to Syntax.trace_ast; global
  6924 timing flag supersedes proof_timing and Toplevel.trace;
  6925 
  6926 * ML: new combinators |>> and |>>> for incremental transformations
  6927 with secondary results (e.g. certain theory extensions):
  6928 
  6929 * ML: PureThy.add_defs gets additional argument to indicate potential
  6930 overloading (usually false);
  6931 
  6932 * ML: PureThy.add_thms/add_axioms/add_defs now return theorems as
  6933 results;
  6934 
  6935 
  6936 
  6937 New in Isabelle99 (October 1999)
  6938 --------------------------------
  6939 
  6940 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  6941 
  6942 * HOL: The THEN and ELSE parts of conditional expressions (if P then x else y)
  6943 are no longer simplified.  (This allows the simplifier to unfold recursive
  6944 functional programs.)  To restore the old behaviour, declare
  6945 
  6946     Delcongs [if_weak_cong];
  6947 
  6948 * HOL: Removed the obsolete syntax "Compl A"; use -A for set
  6949 complement;
  6950 
  6951 * HOL: the predicate "inj" is now defined by translation to "inj_on";
  6952 
  6953 * HOL/datatype: mutual_induct_tac no longer exists --
  6954   use induct_tac "x_1 ... x_n" instead of mutual_induct_tac ["x_1", ..., "x_n"]
  6955 
  6956 * HOL/typedef: fixed type inference for representing set; type
  6957 arguments now have to occur explicitly on the rhs as type constraints;
  6958 
  6959 * ZF: The con_defs part of an inductive definition may no longer refer
  6960 to constants declared in the same theory;
  6961 
  6962 * HOL, ZF: the function mk_cases, generated by the inductive
  6963 definition package, has lost an argument.  To simplify its result, it
  6964 uses the default simpset instead of a supplied list of theorems.
  6965 
  6966 * HOL/List: the constructors of type list are now Nil and Cons;
  6967 
  6968 * Simplifier: the type of the infix ML functions
  6969         setSSolver addSSolver setSolver addSolver
  6970 is now  simpset * solver -> simpset  where `solver' is a new abstract type
  6971 for packaging solvers. A solver is created via
  6972         mk_solver: string -> (thm list -> int -> tactic) -> solver
  6973 where the string argument is only a comment.
  6974 
  6975 
  6976 *** Proof tools ***
  6977 
  6978 * Provers/Arith/fast_lin_arith.ML contains a functor for creating a
  6979 decision procedure for linear arithmetic. Currently it is used for
  6980 types `nat', `int', and `real' in HOL (see below); it can, should and
  6981 will be instantiated for other types and logics as well.
  6982 
  6983 * The simplifier now accepts rewrite rules with flexible heads, eg
  6984      hom ?f ==> ?f(?x+?y) = ?f ?x + ?f ?y
  6985   They are applied like any rule with a non-pattern lhs, i.e. by first-order
  6986   matching.
  6987 
  6988 
  6989 *** General ***
  6990 
  6991 * New Isabelle/Isar subsystem provides an alternative to traditional
  6992 tactical theorem proving; together with the ProofGeneral/isar user
  6993 interface it offers an interactive environment for developing human
  6994 readable proof documents (Isar == Intelligible semi-automated
  6995 reasoning); for further information see isatool doc isar-ref,
  6996 src/HOL/Isar_examples and http://isabelle.in.tum.de/Isar/
  6997 
  6998 * improved and simplified presentation of theories: better HTML markup
  6999 (including colors), graph views in several sizes; isatool usedir now
  7000 provides a proper interface for user theories (via -P option); actual
  7001 document preparation based on (PDF)LaTeX is available as well (for
  7002 new-style theories only); see isatool doc system for more information;
  7003 
  7004 * native support for Proof General, both for classic Isabelle and
  7005 Isabelle/Isar;
  7006 
  7007 * ML function thm_deps visualizes dependencies of theorems and lemmas,
  7008 using the graph browser tool;
  7009 
  7010 * Isabelle manuals now also available as PDF;
  7011 
  7012 * theory loader rewritten from scratch (may not be fully
  7013 bug-compatible); old loadpath variable has been replaced by show_path,
  7014 add_path, del_path, reset_path functions; new operations such as
  7015 update_thy, touch_thy, remove_thy, use/update_thy_only (see also
  7016 isatool doc ref);
  7017 
  7018 * improved isatool install: option -k creates KDE application icon,
  7019 option -p DIR installs standalone binaries;
  7020 
  7021 * added ML_PLATFORM setting (useful for cross-platform installations);
  7022 more robust handling of platform specific ML images for SML/NJ;
  7023 
  7024 * the settings environment is now statically scoped, i.e. it is never
  7025 created again in sub-processes invoked from isabelle, isatool, or
  7026 Isabelle;
  7027 
  7028 * path element specification '~~' refers to '$ISABELLE_HOME';
  7029 
  7030 * in locales, the "assumes" and "defines" parts may be omitted if
  7031 empty;
  7032 
  7033 * new print_mode "xsymbols" for extended symbol support (e.g. genuine
  7034 long arrows);
  7035 
  7036 * new print_mode "HTML";
  7037 
  7038 * new flag show_tags controls display of tags of theorems (which are
  7039 basically just comments that may be attached by some tools);
  7040 
  7041 * Isamode 2.6 requires patch to accomodate change of Isabelle font
  7042 mode and goal output format:
  7043 
  7044 diff -r Isamode-2.6/elisp/isa-load.el Isamode/elisp/isa-load.el
  7045 244c244
  7046 <       (list (isa-getenv "ISABELLE") "-msymbols" logic-name)
  7047 ---
  7048 >       (list (isa-getenv "ISABELLE") "-misabelle_font" "-msymbols" logic-name)
  7049 diff -r Isabelle-2.6/elisp/isa-proofstate.el Isamode/elisp/isa-proofstate.el
  7050 181c181
  7051 < (defconst proofstate-proofstart-regexp "^Level [0-9]+$"
  7052 ---
  7053 > (defconst proofstate-proofstart-regexp "^Level [0-9]+"
  7054 
  7055 * function bind_thms stores lists of theorems (cf. bind_thm);
  7056 
  7057 * new shorthand tactics ftac, eatac, datac, fatac;
  7058 
  7059 * qed (and friends) now accept "" as result name; in that case the
  7060 theorem is not stored, but proper checks and presentation of the
  7061 result still apply;
  7062 
  7063 * theorem database now also indexes constants "Trueprop", "all",
  7064 "==>", "=="; thus thms_containing, findI etc. may retrieve more rules;
  7065 
  7066 
  7067 *** HOL ***
  7068 
  7069 ** HOL arithmetic **
  7070 
  7071 * There are now decision procedures for linear arithmetic over nat and
  7072 int:
  7073 
  7074 1. arith_tac copes with arbitrary formulae involving `=', `<', `<=',
  7075 `+', `-', `Suc', `min', `max' and numerical constants; other subterms
  7076 are treated as atomic; subformulae not involving type `nat' or `int'
  7077 are ignored; quantified subformulae are ignored unless they are
  7078 positive universal or negative existential. The tactic has to be
  7079 invoked by hand and can be a little bit slow. In particular, the
  7080 running time is exponential in the number of occurrences of `min' and
  7081 `max', and `-' on `nat'.
  7082 
  7083 2. fast_arith_tac is a cut-down version of arith_tac: it only takes
  7084 (negated) (in)equalities among the premises and the conclusion into
  7085 account (i.e. no compound formulae) and does not know about `min' and
  7086 `max', and `-' on `nat'. It is fast and is used automatically by the
  7087 simplifier.
  7088 
  7089 NB: At the moment, these decision procedures do not cope with mixed
  7090 nat/int formulae where the two parts interact, such as `m < n ==>
  7091 int(m) < int(n)'.
  7092 
  7093 * HOL/Numeral provides a generic theory of numerals (encoded
  7094 efficiently as bit strings); setup for types nat/int/real is in place;
  7095 INCOMPATIBILITY: since numeral syntax is now polymorphic, rather than
  7096 int, existing theories and proof scripts may require a few additional
  7097 type constraints;
  7098 
  7099 * integer division and remainder can now be performed on constant
  7100 arguments;
  7101 
  7102 * many properties of integer multiplication, division and remainder
  7103 are now available;
  7104 
  7105 * An interface to the Stanford Validity Checker (SVC) is available through the
  7106 tactic svc_tac.  Propositional tautologies and theorems of linear arithmetic
  7107 are proved automatically.  SVC must be installed separately, and its results
  7108 must be TAKEN ON TRUST (Isabelle does not check the proofs, but tags any
  7109 invocation of the underlying oracle).  For SVC see
  7110   http://verify.stanford.edu/SVC
  7111 
  7112 * IsaMakefile: the HOL-Real target now builds an actual image;
  7113 
  7114 
  7115 ** HOL misc **
  7116 
  7117 * HOL/Real/HahnBanach: the Hahn-Banach theorem for real vector spaces
  7118 (in Isabelle/Isar) -- by Gertrud Bauer;
  7119 
  7120 * HOL/BCV: generic model of bytecode verification, i.e. data-flow
  7121 analysis for assembly languages with subtypes;
  7122 
  7123 * HOL/TLA (Lamport's Temporal Logic of Actions): major reorganization
  7124 -- avoids syntactic ambiguities and treats state, transition, and
  7125 temporal levels more uniformly; introduces INCOMPATIBILITIES due to
  7126 changed syntax and (many) tactics;
  7127 
  7128 * HOL/inductive: Now also handles more general introduction rules such
  7129   as "ALL y. (y, x) : r --> y : acc r ==> x : acc r"; monotonicity
  7130   theorems are now maintained within the theory (maintained via the
  7131   "mono" attribute);
  7132 
  7133 * HOL/datatype: Now also handles arbitrarily branching datatypes
  7134   (using function types) such as
  7135 
  7136   datatype 'a tree = Atom 'a | Branch "nat => 'a tree"
  7137 
  7138 * HOL/record: record_simproc (part of the default simpset) takes care
  7139 of selectors applied to updated records; record_split_tac is no longer
  7140 part of the default claset; update_defs may now be removed from the
  7141 simpset in many cases; COMPATIBILITY: old behavior achieved by
  7142 
  7143   claset_ref () := claset() addSWrapper record_split_wrapper;
  7144   Delsimprocs [record_simproc]
  7145 
  7146 * HOL/typedef: fixed type inference for representing set; type
  7147 arguments now have to occur explicitly on the rhs as type constraints;
  7148 
  7149 * HOL/recdef (TFL): 'congs' syntax now expects comma separated list of theorem
  7150 names rather than an ML expression;
  7151 
  7152 * HOL/defer_recdef (TFL): like recdef but the well-founded relation can be
  7153 supplied later.  Program schemes can be defined, such as
  7154     "While B C s = (if B s then While B C (C s) else s)"
  7155 where the well-founded relation can be chosen after B and C have been given.
  7156 
  7157 * HOL/List: the constructors of type list are now Nil and Cons;
  7158 INCOMPATIBILITY: while [] and infix # syntax is still there, of
  7159 course, ML tools referring to List.list.op # etc. have to be adapted;
  7160 
  7161 * HOL_quantifiers flag superseded by "HOL" print mode, which is
  7162 disabled by default; run isabelle with option -m HOL to get back to
  7163 the original Gordon/HOL-style output;
  7164 
  7165 * HOL/Ord.thy: new bounded quantifier syntax (input only): ALL x<y. P,
  7166 ALL x<=y. P, EX x<y. P, EX x<=y. P;
  7167 
  7168 * HOL basic syntax simplified (more orthogonal): all variants of
  7169 All/Ex now support plain / symbolic / HOL notation; plain syntax for
  7170 Eps operator is provided as well: "SOME x. P[x]";
  7171 
  7172 * HOL/Sum.thy: sum_case has been moved to HOL/Datatype;
  7173 
  7174 * HOL/Univ.thy: infix syntax <*>, <+>, <**>, <+> eliminated and made
  7175 thus available for user theories;
  7176 
  7177 * HOLCF/IOA/Sequents: renamed 'Cons' to 'Consq' to avoid clash with
  7178 HOL/List; hardly an INCOMPATIBILITY since '>>' syntax is used all the
  7179 time;
  7180 
  7181 * HOL: new tactic smp_tac: int -> int -> tactic, which applies spec
  7182 several times and then mp;
  7183 
  7184 
  7185 *** LK ***
  7186 
  7187 * the notation <<...>> is now available as a notation for sequences of
  7188 formulas;
  7189 
  7190 * the simplifier is now installed
  7191 
  7192 * the axiom system has been generalized (thanks to Soren Heilmann)
  7193 
  7194 * the classical reasoner now has a default rule database
  7195 
  7196 
  7197 *** ZF ***
  7198 
  7199 * new primrec section allows primitive recursive functions to be given
  7200 directly (as in HOL) over datatypes and the natural numbers;
  7201 
  7202 * new tactics induct_tac and exhaust_tac for induction (or case
  7203 analysis) over datatypes and the natural numbers;
  7204 
  7205 * the datatype declaration of type T now defines the recursor T_rec;
  7206 
  7207 * simplification automatically does freeness reasoning for datatype
  7208 constructors;
  7209 
  7210 * automatic type-inference, with AddTCs command to insert new
  7211 type-checking rules;
  7212 
  7213 * datatype introduction rules are now added as Safe Introduction rules
  7214 to the claset;
  7215 
  7216 * the syntax "if P then x else y" is now available in addition to
  7217 if(P,x,y);
  7218 
  7219 
  7220 *** Internal programming interfaces ***
  7221 
  7222 * tuned simplifier trace output; new flag debug_simp;
  7223 
  7224 * structures Vartab / Termtab (instances of TableFun) offer efficient
  7225 tables indexed by indexname_ord / term_ord (compatible with aconv);
  7226 
  7227 * AxClass.axclass_tac lost the theory argument;
  7228 
  7229 * tuned current_goals_markers semantics: begin / end goal avoids
  7230 printing empty lines;
  7231 
  7232 * removed prs and prs_fn hook, which was broken because it did not
  7233 include \n in its semantics, forcing writeln to add one
  7234 uncoditionally; replaced prs_fn by writeln_fn; consider std_output:
  7235 string -> unit if you really want to output text without newline;
  7236 
  7237 * Symbol.output subject to print mode; INCOMPATIBILITY: defaults to
  7238 plain output, interface builders may have to enable 'isabelle_font'
  7239 mode to get Isabelle font glyphs as before;
  7240 
  7241 * refined token_translation interface; INCOMPATIBILITY: output length
  7242 now of type real instead of int;
  7243 
  7244 * theory loader actions may be traced via new ThyInfo.add_hook
  7245 interface (see src/Pure/Thy/thy_info.ML); example application: keep
  7246 your own database of information attached to *whole* theories -- as
  7247 opposed to intra-theory data slots offered via TheoryDataFun;
  7248 
  7249 * proper handling of dangling sort hypotheses (at last!);
  7250 Thm.strip_shyps and Drule.strip_shyps_warning take care of removing
  7251 extra sort hypotheses that can be witnessed from the type signature;
  7252 the force_strip_shyps flag is gone, any remaining shyps are simply
  7253 left in the theorem (with a warning issued by strip_shyps_warning);
  7254 
  7255 
  7256 
  7257 New in Isabelle98-1 (October 1998)
  7258 ----------------------------------
  7259 
  7260 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  7261 
  7262 * several changes of automated proof tools;
  7263 
  7264 * HOL: major changes to the inductive and datatype packages, including
  7265 some minor incompatibilities of theory syntax;
  7266 
  7267 * HOL: renamed r^-1 to 'converse' from 'inverse'; 'inj_onto' is now
  7268 called `inj_on';
  7269 
  7270 * HOL: removed duplicate thms in Arith:
  7271   less_imp_add_less  should be replaced by  trans_less_add1
  7272   le_imp_add_le      should be replaced by  trans_le_add1
  7273 
  7274 * HOL: unary minus is now overloaded (new type constraints may be
  7275 required);
  7276 
  7277 * HOL and ZF: unary minus for integers is now #- instead of #~.  In
  7278 ZF, expressions such as n#-1 must be changed to n#- 1, since #-1 is
  7279 now taken as an integer constant.
  7280 
  7281 * Pure: ML function 'theory_of' renamed to 'theory';
  7282 
  7283 
  7284 *** Proof tools ***
  7285 
  7286 * Simplifier:
  7287   1. Asm_full_simp_tac is now more aggressive.
  7288      1. It will sometimes reorient premises if that increases their power to
  7289         simplify.
  7290      2. It does no longer proceed strictly from left to right but may also
  7291         rotate premises to achieve further simplification.
  7292      For compatibility reasons there is now Asm_lr_simp_tac which is like the
  7293      old Asm_full_simp_tac in that it does not rotate premises.
  7294   2. The simplifier now knows a little bit about nat-arithmetic.
  7295 
  7296 * Classical reasoner: wrapper mechanism for the classical reasoner now
  7297 allows for selected deletion of wrappers, by introduction of names for
  7298 wrapper functionals.  This implies that addbefore, addSbefore,
  7299 addaltern, and addSaltern now take a pair (name, tactic) as argument,
  7300 and that adding two tactics with the same name overwrites the first
  7301 one (emitting a warning).
  7302   type wrapper = (int -> tactic) -> (int -> tactic)
  7303   setWrapper, setSWrapper, compWrapper and compSWrapper are replaced by
  7304   addWrapper, addSWrapper: claset * (string * wrapper) -> claset
  7305   delWrapper, delSWrapper: claset *  string            -> claset
  7306   getWrapper is renamed to appWrappers, getSWrapper to appSWrappers;
  7307 
  7308 * Classical reasoner: addbefore/addSbefore now have APPEND/ORELSE
  7309 semantics; addbefore now affects only the unsafe part of step_tac
  7310 etc.; this affects addss/auto_tac/force_tac, so EXISTING PROOFS MAY
  7311 FAIL, but proofs should be fixable easily, e.g. by replacing Auto_tac
  7312 by Force_tac;
  7313 
  7314 * Classical reasoner: setwrapper to setWrapper and compwrapper to
  7315 compWrapper; added safe wrapper (and access functions for it);
  7316 
  7317 * HOL/split_all_tac is now much faster and fails if there is nothing
  7318 to split.  Some EXISTING PROOFS MAY REQUIRE ADAPTION because the order
  7319 and the names of the automatically generated variables have changed.
  7320 split_all_tac has moved within claset() from unsafe wrappers to safe
  7321 wrappers, which means that !!-bound variables are split much more
  7322 aggressively, and safe_tac and clarify_tac now split such variables.
  7323 If this splitting is not appropriate, use delSWrapper "split_all_tac".
  7324 Note: the same holds for record_split_tac, which does the job of
  7325 split_all_tac for record fields.
  7326 
  7327 * HOL/Simplifier: Rewrite rules for case distinctions can now be added
  7328 permanently to the default simpset using Addsplits just like
  7329 Addsimps. They can be removed via Delsplits just like
  7330 Delsimps. Lower-case versions are also available.
  7331 
  7332 * HOL/Simplifier: The rule split_if is now part of the default
  7333 simpset. This means that the simplifier will eliminate all occurrences
  7334 of if-then-else in the conclusion of a goal. To prevent this, you can
  7335 either remove split_if completely from the default simpset by
  7336 `Delsplits [split_if]' or remove it in a specific call of the
  7337 simplifier using `... delsplits [split_if]'.  You can also add/delete
  7338 other case splitting rules to/from the default simpset: every datatype
  7339 generates suitable rules `split_t_case' and `split_t_case_asm' (where
  7340 t is the name of the datatype).
  7341 
  7342 * Classical reasoner / Simplifier combination: new force_tac (and
  7343 derivatives Force_tac, force) combines rewriting and classical
  7344 reasoning (and whatever other tools) similarly to auto_tac, but is
  7345 aimed to solve the given subgoal completely.
  7346 
  7347 
  7348 *** General ***
  7349 
  7350 * new top-level commands `Goal' and `Goalw' that improve upon `goal'
  7351 and `goalw': the theory is no longer needed as an explicit argument -
  7352 the current theory context is used; assumptions are no longer returned
  7353 at the ML-level unless one of them starts with ==> or !!; it is
  7354 recommended to convert to these new commands using isatool fixgoal
  7355 (backup your sources first!);
  7356 
  7357 * new top-level commands 'thm' and 'thms' for retrieving theorems from
  7358 the current theory context, and 'theory' to lookup stored theories;
  7359 
  7360 * new theory section 'locale' for declaring constants, assumptions and
  7361 definitions that have local scope;
  7362 
  7363 * new theory section 'nonterminals' for purely syntactic types;
  7364 
  7365 * new theory section 'setup' for generic ML setup functions
  7366 (e.g. package initialization);
  7367 
  7368 * the distribution now includes Isabelle icons: see
  7369 lib/logo/isabelle-{small,tiny}.xpm;
  7370 
  7371 * isatool install - install binaries with absolute references to
  7372 ISABELLE_HOME/bin;
  7373 
  7374 * isatool logo -- create instances of the Isabelle logo (as EPS);
  7375 
  7376 * print mode 'emacs' reserved for Isamode;
  7377 
  7378 * support multiple print (ast) translations per constant name;
  7379 
  7380 * theorems involving oracles are now printed with a suffixed [!];
  7381 
  7382 
  7383 *** HOL ***
  7384 
  7385 * there is now a tutorial on Isabelle/HOL (do 'isatool doc tutorial');
  7386 
  7387 * HOL/inductive package reorganized and improved: now supports mutual
  7388 definitions such as
  7389 
  7390   inductive EVEN ODD
  7391     intrs
  7392       null "0 : EVEN"
  7393       oddI "n : EVEN ==> Suc n : ODD"
  7394       evenI "n : ODD ==> Suc n : EVEN"
  7395 
  7396 new theorem list "elims" contains an elimination rule for each of the
  7397 recursive sets; inductive definitions now handle disjunctive premises
  7398 correctly (also ZF);
  7399 
  7400 INCOMPATIBILITIES: requires Inductive as an ancestor; component
  7401 "mutual_induct" no longer exists - the induction rule is always
  7402 contained in "induct";
  7403 
  7404 
  7405 * HOL/datatype package re-implemented and greatly improved: now
  7406 supports mutually recursive datatypes such as
  7407 
  7408   datatype
  7409     'a aexp = IF_THEN_ELSE ('a bexp) ('a aexp) ('a aexp)
  7410             | SUM ('a aexp) ('a aexp)
  7411             | DIFF ('a aexp) ('a aexp)
  7412             | NUM 'a
  7413   and
  7414     'a bexp = LESS ('a aexp) ('a aexp)
  7415             | AND ('a bexp) ('a bexp)
  7416             | OR ('a bexp) ('a bexp)
  7417 
  7418 as well as indirectly recursive datatypes such as
  7419 
  7420   datatype
  7421     ('a, 'b) term = Var 'a
  7422                   | App 'b ((('a, 'b) term) list)
  7423 
  7424 The new tactic  mutual_induct_tac [<var_1>, ..., <var_n>] i  performs
  7425 induction on mutually / indirectly recursive datatypes.
  7426 
  7427 Primrec equations are now stored in theory and can be accessed via
  7428 <function_name>.simps.
  7429 
  7430 INCOMPATIBILITIES:
  7431 
  7432   - Theories using datatypes must now have theory Datatype as an
  7433     ancestor.
  7434   - The specific <typename>.induct_tac no longer exists - use the
  7435     generic induct_tac instead.
  7436   - natE has been renamed to nat.exhaust - use exhaust_tac
  7437     instead of res_inst_tac ... natE. Note that the variable
  7438     names in nat.exhaust differ from the names in natE, this
  7439     may cause some "fragile" proofs to fail.
  7440   - The theorems split_<typename>_case and split_<typename>_case_asm
  7441     have been renamed to <typename>.split and <typename>.split_asm.
  7442   - Since default sorts of type variables are now handled correctly,
  7443     some datatype definitions may have to be annotated with explicit
  7444     sort constraints.
  7445   - Primrec definitions no longer require function name and type
  7446     of recursive argument.
  7447 
  7448 Consider using isatool fixdatatype to adapt your theories and proof
  7449 scripts to the new package (backup your sources first!).
  7450 
  7451 
  7452 * HOL/record package: considerably improved implementation; now
  7453 includes concrete syntax for record types, terms, updates; theorems
  7454 for surjective pairing and splitting !!-bound record variables; proof
  7455 support is as follows:
  7456 
  7457   1) standard conversions (selectors or updates applied to record
  7458 constructor terms) are part of the standard simpset;
  7459 
  7460   2) inject equations of the form ((x, y) = (x', y')) == x=x' & y=y' are
  7461 made part of standard simpset and claset via addIffs;
  7462 
  7463   3) a tactic for record field splitting (record_split_tac) is part of
  7464 the standard claset (addSWrapper);
  7465 
  7466 To get a better idea about these rules you may retrieve them via
  7467 something like 'thms "foo.simps"' or 'thms "foo.iffs"', where "foo" is
  7468 the name of your record type.
  7469 
  7470 The split tactic 3) conceptually simplifies by the following rule:
  7471 
  7472   "(!!x. PROP ?P x) == (!!a b. PROP ?P (a, b))"
  7473 
  7474 Thus any record variable that is bound by meta-all will automatically
  7475 blow up into some record constructor term, consequently the
  7476 simplifications of 1), 2) apply.  Thus force_tac, auto_tac etc. shall
  7477 solve record problems automatically.
  7478 
  7479 
  7480 * reorganized the main HOL image: HOL/Integ and String loaded by
  7481 default; theory Main includes everything;
  7482 
  7483 * automatic simplification of integer sums and comparisons, using cancellation;
  7484 
  7485 * added option_map_eq_Some and not_Some_eq to the default simpset and claset;
  7486 
  7487 * added disj_not1 = "(~P | Q) = (P --> Q)" to the default simpset;
  7488 
  7489 * many new identities for unions, intersections, set difference, etc.;
  7490 
  7491 * expand_if, expand_split, expand_sum_case and expand_nat_case are now
  7492 called split_if, split_split, split_sum_case and split_nat_case (to go
  7493 with add/delsplits);
  7494 
  7495 * HOL/Prod introduces simplification procedure unit_eq_proc rewriting
  7496 (?x::unit) = (); this is made part of the default simpset, which COULD
  7497 MAKE EXISTING PROOFS FAIL under rare circumstances (consider
  7498 'Delsimprocs [unit_eq_proc];' as last resort); also note that
  7499 unit_abs_eta_conv is added in order to counter the effect of
  7500 unit_eq_proc on (%u::unit. f u), replacing it by f rather than by
  7501 %u.f();
  7502 
  7503 * HOL/Fun INCOMPATIBILITY: `inj_onto' is now called `inj_on' (which
  7504 makes more sense);
  7505 
  7506 * HOL/Set INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  7507   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  7508   disjointness reasoning but breaking a few old proofs.
  7509 
  7510 * HOL/Relation INCOMPATIBILITY: renamed the relational operator r^-1
  7511 to 'converse' from 'inverse' (for compatibility with ZF and some
  7512 literature);
  7513 
  7514 * HOL/recdef can now declare non-recursive functions, with {} supplied as
  7515 the well-founded relation;
  7516 
  7517 * HOL/Set INCOMPATIBILITY: the complement of set A is now written -A instead of
  7518     Compl A.  The "Compl" syntax remains available as input syntax for this
  7519     release ONLY.
  7520 
  7521 * HOL/Update: new theory of function updates:
  7522     f(a:=b) == %x. if x=a then b else f x
  7523 may also be iterated as in f(a:=b,c:=d,...);
  7524 
  7525 * HOL/Vimage: new theory for inverse image of a function, syntax f-``B;
  7526 
  7527 * HOL/List:
  7528   - new function list_update written xs[i:=v] that updates the i-th
  7529     list position. May also be iterated as in xs[i:=a,j:=b,...].
  7530   - new function `upt' written [i..j(] which generates the list
  7531     [i,i+1,...,j-1], i.e. the upper bound is excluded. To include the upper
  7532     bound write [i..j], which is a shorthand for [i..j+1(].
  7533   - new lexicographic orderings and corresponding wellfoundedness theorems.
  7534 
  7535 * HOL/Arith:
  7536   - removed 'pred' (predecessor) function;
  7537   - generalized some theorems about n-1;
  7538   - many new laws about "div" and "mod";
  7539   - new laws about greatest common divisors (see theory ex/Primes);
  7540 
  7541 * HOL/Relation: renamed the relational operator r^-1 "converse"
  7542 instead of "inverse";
  7543 
  7544 * HOL/Induct/Multiset: a theory of multisets, including the wellfoundedness
  7545   of the multiset ordering;
  7546 
  7547 * directory HOL/Real: a construction of the reals using Dedekind cuts
  7548   (not included by default);
  7549 
  7550 * directory HOL/UNITY: Chandy and Misra's UNITY formalism;
  7551 
  7552 * directory HOL/Hoare: a new version of Hoare logic which permits many-sorted
  7553   programs, i.e. different program variables may have different types.
  7554 
  7555 * calling (stac rew i) now fails if "rew" has no effect on the goal
  7556   [previously, this check worked only if the rewrite rule was unconditional]
  7557   Now rew can involve either definitions or equalities (either == or =).
  7558 
  7559 
  7560 *** ZF ***
  7561 
  7562 * theory Main includes everything; INCOMPATIBILITY: theory ZF.thy contains
  7563   only the theorems proved on ZF.ML;
  7564 
  7565 * ZF INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  7566   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  7567   disjointness reasoning but breaking a few old proofs.
  7568 
  7569 * ZF/Update: new theory of function updates
  7570     with default rewrite rule  f(x:=y) ` z = if(z=x, y, f`z)
  7571   may also be iterated as in f(a:=b,c:=d,...);
  7572 
  7573 * in  let x=t in u(x), neither t nor u(x) has to be an FOL term.
  7574 
  7575 * calling (stac rew i) now fails if "rew" has no effect on the goal
  7576   [previously, this check worked only if the rewrite rule was unconditional]
  7577   Now rew can involve either definitions or equalities (either == or =).
  7578 
  7579 * case_tac provided for compatibility with HOL
  7580     (like the old excluded_middle_tac, but with subgoals swapped)
  7581 
  7582 
  7583 *** Internal programming interfaces ***
  7584 
  7585 * Pure: several new basic modules made available for general use, see
  7586 also src/Pure/README;
  7587 
  7588 * improved the theory data mechanism to support encapsulation (data
  7589 kind name replaced by private Object.kind, acting as authorization
  7590 key); new type-safe user interface via functor TheoryDataFun; generic
  7591 print_data function becomes basically useless;
  7592 
  7593 * removed global_names compatibility flag -- all theory declarations
  7594 are qualified by default;
  7595 
  7596 * module Pure/Syntax now offers quote / antiquote translation
  7597 functions (useful for Hoare logic etc. with implicit dependencies);
  7598 see HOL/ex/Antiquote for an example use;
  7599 
  7600 * Simplifier now offers conversions (asm_)(full_)rewrite: simpset ->
  7601 cterm -> thm;
  7602 
  7603 * new tactical CHANGED_GOAL for checking that a tactic modifies a
  7604 subgoal;
  7605 
  7606 * Display.print_goals function moved to Locale.print_goals;
  7607 
  7608 * standard print function for goals supports current_goals_markers
  7609 variable for marking begin of proof, end of proof, start of goal; the
  7610 default is ("", "", ""); setting current_goals_markers := ("<proof>",
  7611 "</proof>", "<goal>") causes SGML like tagged proof state printing,
  7612 for example;
  7613 
  7614 
  7615 
  7616 New in Isabelle98 (January 1998)
  7617 --------------------------------
  7618 
  7619 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  7620 
  7621 * changed lexical syntax of terms / types: dots made part of long
  7622 identifiers, e.g. "%x.x" no longer possible, should be "%x. x";
  7623 
  7624 * simpset (and claset) reference variable replaced by functions
  7625 simpset / simpset_ref;
  7626 
  7627 * no longer supports theory aliases (via merge) and non-trivial
  7628 implicit merge of thms' signatures;
  7629 
  7630 * most internal names of constants changed due to qualified names;
  7631 
  7632 * changed Pure/Sequence interface (see Pure/seq.ML);
  7633 
  7634 
  7635 *** General Changes ***
  7636 
  7637 * hierachically structured name spaces (for consts, types, axms, thms
  7638 etc.); new lexical class 'longid' (e.g. Foo.bar.x) may render much of
  7639 old input syntactically incorrect (e.g. "%x.x"); COMPATIBILITY:
  7640 isatool fixdots ensures space after dots (e.g. "%x. x"); set
  7641 long_names for fully qualified output names; NOTE: ML programs
  7642 (special tactics, packages etc.) referring to internal names may have
  7643 to be adapted to cope with fully qualified names; in case of severe
  7644 backward campatibility problems try setting 'global_names' at compile
  7645 time to have enrything declared within a flat name space; one may also
  7646 fine tune name declarations in theories via the 'global' and 'local'
  7647 section;
  7648 
  7649 * reimplemented the implicit simpset and claset using the new anytype
  7650 data filed in signatures; references simpset:simpset ref etc. are
  7651 replaced by functions simpset:unit->simpset and
  7652 simpset_ref:unit->simpset ref; COMPATIBILITY: use isatool fixclasimp
  7653 to patch your ML files accordingly;
  7654 
  7655 * HTML output now includes theory graph data for display with Java
  7656 applet or isatool browser; data generated automatically via isatool
  7657 usedir (see -i option, ISABELLE_USEDIR_OPTIONS);
  7658 
  7659 * defs may now be conditional; improved rewrite_goals_tac to handle
  7660 conditional equations;
  7661 
  7662 * defs now admits additional type arguments, using TYPE('a) syntax;
  7663 
  7664 * theory aliases via merge (e.g. M=A+B+C) no longer supported, always
  7665 creates a new theory node; implicit merge of thms' signatures is
  7666 restricted to 'trivial' ones; COMPATIBILITY: one may have to use
  7667 transfer:theory->thm->thm in (rare) cases;
  7668 
  7669 * improved handling of draft signatures / theories; draft thms (and
  7670 ctyps, cterms) are automatically promoted to real ones;
  7671 
  7672 * slightly changed interfaces for oracles: admit many per theory, named
  7673 (e.g. oracle foo = mlfun), additional name argument for invoke_oracle;
  7674 
  7675 * print_goals: optional output of const types (set show_consts and
  7676 show_types);
  7677 
  7678 * improved output of warnings (###) and errors (***);
  7679 
  7680 * subgoal_tac displays a warning if the new subgoal has type variables;
  7681 
  7682 * removed old README and Makefiles;
  7683 
  7684 * replaced print_goals_ref hook by print_current_goals_fn and result_error_fn;
  7685 
  7686 * removed obsolete init_pps and init_database;
  7687 
  7688 * deleted the obsolete tactical STATE, which was declared by
  7689     fun STATE tacfun st = tacfun st st;
  7690 
  7691 * cd and use now support path variables, e.g. $ISABELLE_HOME, or ~
  7692 (which abbreviates $HOME);
  7693 
  7694 * changed Pure/Sequence interface (see Pure/seq.ML); COMPATIBILITY:
  7695 use isatool fixseq to adapt your ML programs (this works for fully
  7696 qualified references to the Sequence structure only!);
  7697 
  7698 * use_thy no longer requires writable current directory; it always
  7699 reloads .ML *and* .thy file, if either one is out of date;
  7700 
  7701 
  7702 *** Classical Reasoner ***
  7703 
  7704 * Clarify_tac, clarify_tac, clarify_step_tac, Clarify_step_tac: new
  7705 tactics that use classical reasoning to simplify a subgoal without
  7706 splitting it into several subgoals;
  7707 
  7708 * Safe_tac: like safe_tac but uses the default claset;
  7709 
  7710 
  7711 *** Simplifier ***
  7712 
  7713 * added simplification meta rules:
  7714     (asm_)(full_)simplify: simpset -> thm -> thm;
  7715 
  7716 * simplifier.ML no longer part of Pure -- has to be loaded by object
  7717 logics (again);
  7718 
  7719 * added prems argument to simplification procedures;
  7720 
  7721 * HOL, FOL, ZF: added infix function `addsplits':
  7722   instead of `<simpset> setloop (split_tac <thms>)'
  7723   you can simply write `<simpset> addsplits <thms>'
  7724 
  7725 
  7726 *** Syntax ***
  7727 
  7728 * TYPE('a) syntax for type reflection terms;
  7729 
  7730 * no longer handles consts with name "" -- declare as 'syntax' instead;
  7731 
  7732 * pretty printer: changed order of mixfix annotation preference (again!);
  7733 
  7734 * Pure: fixed idt/idts vs. pttrn/pttrns syntactic categories;
  7735 
  7736 
  7737 *** HOL ***
  7738 
  7739 * HOL: there is a new splitter `split_asm_tac' that can be used e.g.
  7740   with `addloop' of the simplifier to faciliate case splitting in premises.
  7741 
  7742 * HOL/TLA: Stephan Merz's formalization of Lamport's Temporal Logic of Actions;
  7743 
  7744 * HOL/Auth: new protocol proofs including some for the Internet
  7745   protocol TLS;
  7746 
  7747 * HOL/Map: new theory of `maps' a la VDM;
  7748 
  7749 * HOL/simplifier: simplification procedures nat_cancel_sums for
  7750 cancelling out common nat summands from =, <, <= (in)equalities, or
  7751 differences; simplification procedures nat_cancel_factor for
  7752 cancelling common factor from =, <, <= (in)equalities over natural
  7753 sums; nat_cancel contains both kinds of procedures, it is installed by
  7754 default in Arith.thy -- this COULD MAKE EXISTING PROOFS FAIL;
  7755 
  7756 * HOL/simplifier: terms of the form
  7757   `? x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x)'  (or t=x)
  7758   are rewritten to
  7759   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t)',
  7760   and those of the form
  7761   `! x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x) --> R(x)'  (or t=x)
  7762   are rewritten to
  7763   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t) --> R(t)',
  7764 
  7765 * HOL/datatype
  7766   Each datatype `t' now comes with a theorem `split_t_case' of the form
  7767 
  7768   P(t_case f1 ... fn x) =
  7769      ( (!y1 ... ym1. x = C1 y1 ... ym1 --> P(f1 y1 ... ym1)) &
  7770         ...
  7771        (!y1 ... ymn. x = Cn y1 ... ymn --> P(f1 y1 ... ymn))
  7772      )
  7773 
  7774   and a theorem `split_t_case_asm' of the form
  7775 
  7776   P(t_case f1 ... fn x) =
  7777     ~( (? y1 ... ym1. x = C1 y1 ... ym1 & ~P(f1 y1 ... ym1)) |
  7778         ...
  7779        (? y1 ... ymn. x = Cn y1 ... ymn & ~P(f1 y1 ... ymn))
  7780      )
  7781   which can be added to a simpset via `addsplits'. The existing theorems
  7782   expand_list_case and expand_option_case have been renamed to
  7783   split_list_case and split_option_case.
  7784 
  7785 * HOL/Arithmetic:
  7786   - `pred n' is automatically converted to `n-1'.
  7787     Users are strongly encouraged not to use `pred' any longer,
  7788     because it will disappear altogether at some point.
  7789   - Users are strongly encouraged to write "0 < n" rather than
  7790     "n ~= 0". Theorems and proof tools have been modified towards this
  7791     `standard'.
  7792 
  7793 * HOL/Lists:
  7794   the function "set_of_list" has been renamed "set" (and its theorems too);
  7795   the function "nth" now takes its arguments in the reverse order and
  7796   has acquired the infix notation "!" as in "xs!n".
  7797 
  7798 * HOL/Set: UNIV is now a constant and is no longer translated to Compl{};
  7799 
  7800 * HOL/Set: The operator (UN x.B x) now abbreviates (UN x:UNIV. B x) and its
  7801   specialist theorems (like UN1_I) are gone.  Similarly for (INT x.B x);
  7802 
  7803 * HOL/record: extensible records with schematic structural subtyping
  7804 (single inheritance); EXPERIMENTAL version demonstrating the encoding,
  7805 still lacks various theorems and concrete record syntax;
  7806 
  7807 
  7808 *** HOLCF ***
  7809 
  7810 * removed "axioms" and "generated by" sections;
  7811 
  7812 * replaced "ops" section by extended "consts" section, which is capable of
  7813   handling the continuous function space "->" directly;
  7814 
  7815 * domain package:
  7816   . proves theorems immediately and stores them in the theory,
  7817   . creates hierachical name space,
  7818   . now uses normal mixfix annotations (instead of cinfix...),
  7819   . minor changes to some names and values (for consistency),
  7820   . e.g. cases -> casedist, dists_eq -> dist_eqs, [take_lemma] -> take_lemmas,
  7821   . separator between mutual domain defs: changed "," to "and",
  7822   . improved handling of sort constraints;  now they have to
  7823     appear on the left-hand side of the equations only;
  7824 
  7825 * fixed LAM <x,y,zs>.b syntax;
  7826 
  7827 * added extended adm_tac to simplifier in HOLCF -- can now discharge
  7828 adm (%x. P (t x)), where P is chainfinite and t continuous;
  7829 
  7830 
  7831 *** FOL and ZF ***
  7832 
  7833 * FOL: there is a new splitter `split_asm_tac' that can be used e.g.
  7834   with `addloop' of the simplifier to faciliate case splitting in premises.
  7835 
  7836 * qed_spec_mp, qed_goal_spec_mp, qed_goalw_spec_mp are available, as
  7837 in HOL, they strip ALL and --> from proved theorems;
  7838 
  7839 
  7840 
  7841 New in Isabelle94-8 (May 1997)
  7842 ------------------------------
  7843 
  7844 *** General Changes ***
  7845 
  7846 * new utilities to build / run / maintain Isabelle etc. (in parts
  7847 still somewhat experimental); old Makefiles etc. still functional;
  7848 
  7849 * new 'Isabelle System Manual';
  7850 
  7851 * INSTALL text, together with ./configure and ./build scripts;
  7852 
  7853 * reimplemented type inference for greater efficiency, better error
  7854 messages and clean internal interface;
  7855 
  7856 * prlim command for dealing with lots of subgoals (an easier way of
  7857 setting goals_limit);
  7858 
  7859 
  7860 *** Syntax ***
  7861 
  7862 * supports alternative (named) syntax tables (parser and pretty
  7863 printer); internal interface is provided by add_modesyntax(_i);
  7864 
  7865 * Pure, FOL, ZF, HOL, HOLCF now support symbolic input and output; to
  7866 be used in conjunction with the Isabelle symbol font; uses the
  7867 "symbols" syntax table;
  7868 
  7869 * added token_translation interface (may translate name tokens in
  7870 arbitrary ways, dependent on their type (free, bound, tfree, ...) and
  7871 the current print_mode); IMPORTANT: user print translation functions
  7872 are responsible for marking newly introduced bounds
  7873 (Syntax.mark_boundT);
  7874 
  7875 * token translations for modes "xterm" and "xterm_color" that display
  7876 names in bold, underline etc. or colors (which requires a color
  7877 version of xterm);
  7878 
  7879 * infixes may now be declared with names independent of their syntax;
  7880 
  7881 * added typed_print_translation (like print_translation, but may
  7882 access type of constant);
  7883 
  7884 
  7885 *** Classical Reasoner ***
  7886 
  7887 Blast_tac: a new tactic!  It is often more powerful than fast_tac, but has
  7888 some limitations.  Blast_tac...
  7889   + ignores addss, addbefore, addafter; this restriction is intrinsic
  7890   + ignores elimination rules that don't have the correct format
  7891         (the conclusion MUST be a formula variable)
  7892   + ignores types, which can make HOL proofs fail
  7893   + rules must not require higher-order unification, e.g. apply_type in ZF
  7894     [message "Function Var's argument not a bound variable" relates to this]
  7895   + its proof strategy is more general but can actually be slower
  7896 
  7897 * substitution with equality assumptions no longer permutes other
  7898 assumptions;
  7899 
  7900 * minor changes in semantics of addafter (now called addaltern); renamed
  7901 setwrapper to setWrapper and compwrapper to compWrapper; added safe wrapper
  7902 (and access functions for it);
  7903 
  7904 * improved combination of classical reasoner and simplifier:
  7905   + functions for handling clasimpsets
  7906   + improvement of addss: now the simplifier is called _after_ the
  7907     safe steps.
  7908   + safe variant of addss called addSss: uses safe simplifications
  7909     _during_ the safe steps. It is more complete as it allows multiple
  7910     instantiations of unknowns (e.g. with slow_tac).
  7911 
  7912 *** Simplifier ***
  7913 
  7914 * added interface for simplification procedures (functions that
  7915 produce *proven* rewrite rules on the fly, depending on current
  7916 redex);
  7917 
  7918 * ordering on terms as parameter (used for ordered rewriting);
  7919 
  7920 * new functions delcongs, deleqcongs, and Delcongs. richer rep_ss;
  7921 
  7922 * the solver is now split into a safe and an unsafe part.
  7923 This should be invisible for the normal user, except that the
  7924 functions setsolver and addsolver have been renamed to setSolver and
  7925 addSolver; added safe_asm_full_simp_tac;
  7926 
  7927 
  7928 *** HOL ***
  7929 
  7930 * a generic induction tactic `induct_tac' which works for all datatypes and
  7931 also for type `nat';
  7932 
  7933 * a generic case distinction tactic `exhaust_tac' which works for all
  7934 datatypes and also for type `nat';
  7935 
  7936 * each datatype comes with a function `size';
  7937 
  7938 * patterns in case expressions allow tuple patterns as arguments to
  7939 constructors, for example `case x of [] => ... | (x,y,z)#ps => ...';
  7940 
  7941 * primrec now also works with type nat;
  7942 
  7943 * recdef: a new declaration form, allows general recursive functions to be
  7944 defined in theory files.  See HOL/ex/Fib, HOL/ex/Primes, HOL/Subst/Unify.
  7945 
  7946 * the constant for negation has been renamed from "not" to "Not" to
  7947 harmonize with FOL, ZF, LK, etc.;
  7948 
  7949 * HOL/ex/LFilter theory of a corecursive "filter" functional for
  7950 infinite lists;
  7951 
  7952 * HOL/Modelcheck demonstrates invocation of model checker oracle;
  7953 
  7954 * HOL/ex/Ring.thy declares cring_simp, which solves equational
  7955 problems in commutative rings, using axiomatic type classes for + and *;
  7956 
  7957 * more examples in HOL/MiniML and HOL/Auth;
  7958 
  7959 * more default rewrite rules for quantifiers, union/intersection;
  7960 
  7961 * a new constant `arbitrary == @x.False';
  7962 
  7963 * HOLCF/IOA replaces old HOL/IOA;
  7964 
  7965 * HOLCF changes: derived all rules and arities
  7966   + axiomatic type classes instead of classes
  7967   + typedef instead of faking type definitions
  7968   + eliminated the internal constants less_fun, less_cfun, UU_fun, UU_cfun etc.
  7969   + new axclasses cpo, chfin, flat with flat < chfin < pcpo < cpo < po
  7970   + eliminated the types void, one, tr
  7971   + use unit lift and bool lift (with translations) instead of one and tr
  7972   + eliminated blift from Lift3.thy (use Def instead of blift)
  7973   all eliminated rules are derived as theorems --> no visible changes ;
  7974 
  7975 
  7976 *** ZF ***
  7977 
  7978 * ZF now has Fast_tac, Simp_tac and Auto_tac.  Union_iff is a now a default
  7979 rewrite rule; this may affect some proofs.  eq_cs is gone but can be put back
  7980 as ZF_cs addSIs [equalityI];
  7981 
  7982 
  7983 
  7984 New in Isabelle94-7 (November 96)
  7985 ---------------------------------
  7986 
  7987 * allowing negative levels (as offsets) in prlev and choplev;
  7988 
  7989 * super-linear speedup for large simplifications;
  7990 
  7991 * FOL, ZF and HOL now use miniscoping: rewriting pushes
  7992 quantifications in as far as possible (COULD MAKE EXISTING PROOFS
  7993 FAIL); can suppress it using the command Delsimps (ex_simps @
  7994 all_simps); De Morgan laws are also now included, by default;
  7995 
  7996 * improved printing of ==>  :  ~:
  7997 
  7998 * new object-logic "Sequents" adds linear logic, while replacing LK
  7999 and Modal (thanks to Sara Kalvala);
  8000 
  8001 * HOL/Auth: correctness proofs for authentication protocols;
  8002 
  8003 * HOL: new auto_tac combines rewriting and classical reasoning (many
  8004 examples on HOL/Auth);
  8005 
  8006 * HOL: new command AddIffs for declaring theorems of the form P=Q to
  8007 the rewriter and classical reasoner simultaneously;
  8008 
  8009 * function uresult no longer returns theorems in "standard" format;
  8010 regain previous version by: val uresult = standard o uresult;
  8011 
  8012 
  8013 
  8014 New in Isabelle94-6
  8015 -------------------
  8016 
  8017 * oracles -- these establish an interface between Isabelle and trusted
  8018 external reasoners, which may deliver results as theorems;
  8019 
  8020 * proof objects (in particular record all uses of oracles);
  8021 
  8022 * Simp_tac, Fast_tac, etc. that refer to implicit simpset / claset;
  8023 
  8024 * "constdefs" section in theory files;
  8025 
  8026 * "primrec" section (HOL) no longer requires names;
  8027 
  8028 * internal type "tactic" now simply "thm -> thm Sequence.seq";
  8029 
  8030 
  8031 
  8032 New in Isabelle94-5
  8033 -------------------
  8034 
  8035 * reduced space requirements;
  8036 
  8037 * automatic HTML generation from theories;
  8038 
  8039 * theory files no longer require "..." (quotes) around most types;
  8040 
  8041 * new examples, including two proofs of the Church-Rosser theorem;
  8042 
  8043 * non-curried (1994) version of HOL is no longer distributed;
  8044 
  8045 
  8046 
  8047 New in Isabelle94-4
  8048 -------------------
  8049 
  8050 * greatly reduced space requirements;
  8051 
  8052 * theory files (.thy) no longer require \...\ escapes at line breaks;
  8053 
  8054 * searchable theorem database (see the section "Retrieving theorems" on
  8055 page 8 of the Reference Manual);
  8056 
  8057 * new examples, including Grabczewski's monumental case study of the
  8058 Axiom of Choice;
  8059 
  8060 * The previous version of HOL renamed to Old_HOL;
  8061 
  8062 * The new version of HOL (previously called CHOL) uses a curried syntax
  8063 for functions.  Application looks like f a b instead of f(a,b);
  8064 
  8065 * Mutually recursive inductive definitions finally work in HOL;
  8066 
  8067 * In ZF, pattern-matching on tuples is now available in all abstractions and
  8068 translates to the operator "split";
  8069 
  8070 
  8071 
  8072 New in Isabelle94-3
  8073 -------------------
  8074 
  8075 * new infix operator, addss, allowing the classical reasoner to
  8076 perform simplification at each step of its search.  Example:
  8077         fast_tac (cs addss ss)
  8078 
  8079 * a new logic, CHOL, the same as HOL, but with a curried syntax
  8080 for functions.  Application looks like f a b instead of f(a,b).  Also pairs
  8081 look like (a,b) instead of <a,b>;
  8082 
  8083 * PLEASE NOTE: CHOL will eventually replace HOL!
  8084 
  8085 * In CHOL, pattern-matching on tuples is now available in all abstractions.
  8086 It translates to the operator "split".  A new theory of integers is available;
  8087 
  8088 * In ZF, integer numerals now denote two's-complement binary integers.
  8089 Arithmetic operations can be performed by rewriting.  See ZF/ex/Bin.ML;
  8090 
  8091 * Many new examples: I/O automata, Church-Rosser theorem, equivalents
  8092 of the Axiom of Choice;
  8093 
  8094 
  8095 
  8096 New in Isabelle94-2
  8097 -------------------
  8098 
  8099 * Significantly faster resolution;
  8100 
  8101 * the different sections in a .thy file can now be mixed and repeated
  8102 freely;
  8103 
  8104 * Database of theorems for FOL, HOL and ZF.  New
  8105 commands including qed, qed_goal and bind_thm store theorems in the database.
  8106 
  8107 * Simple database queries: return a named theorem (get_thm) or all theorems of
  8108 a given theory (thms_of), or find out what theory a theorem was proved in
  8109 (theory_of_thm);
  8110 
  8111 * Bugs fixed in the inductive definition and datatype packages;
  8112 
  8113 * The classical reasoner provides deepen_tac and depth_tac, making FOL_dup_cs
  8114 and HOL_dup_cs obsolete;
  8115 
  8116 * Syntactic ambiguities caused by the new treatment of syntax in Isabelle94-1
  8117 have been removed;
  8118 
  8119 * Simpler definition of function space in ZF;
  8120 
  8121 * new results about cardinal and ordinal arithmetic in ZF;
  8122 
  8123 * 'subtype' facility in HOL for introducing new types as subsets of existing
  8124 types;
  8125 
  8126 :mode=text:wrap=hard:maxLineLen=72: