NEWS
author wenzelm
Sun Jan 16 21:10:30 2011 +0100 (2011-01-16)
changeset 41597 ced4f78bb728
parent 41595 d0cced9cdeae
child 41601 fda8511006f9
permissions -rw-r--r--
tuned;
     1 Isabelle NEWS -- history user-relevant changes
     2 ==============================================
     3 
     4 New in Isabelle2011 (January 2011)
     5 ----------------------------------
     6 
     7 *** General ***
     8 
     9 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
    10 src/Tools/jEdit).  A bundled component provides "isabelle jedit" as
    11 executable Isabelle tool.  Note that this also serves as IDE for
    12 Isabelle/ML, with useful tooltips and hyperlinks produced from its
    13 static analysis.
    14 
    15 * Significantly improved Isabelle/Isar implementation manual.
    16 
    17 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
    18 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
    19 while the default heap location within that directory lacks that extra
    20 suffix.  This isolates multiple Isabelle installations from each
    21 other, avoiding problems with old settings in new versions.
    22 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
    23 
    24 * Source files are always encoded as UTF-8, instead of old-fashioned
    25 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
    26 the following package declarations:
    27 
    28   \usepackage[utf8]{inputenc}
    29   \usepackage{textcomp}
    30 
    31 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
    32 a Unicode character is treated as a single symbol, not a sequence of
    33 non-ASCII bytes as before.  Since Isabelle/ML string literals may
    34 contain symbols without further backslash escapes, Unicode can now be
    35 used here as well.  Recall that Symbol.explode in ML provides a
    36 consistent view on symbols, while raw explode (or String.explode)
    37 merely give a byte-oriented representation.
    38 
    39 * Theory loader: source files are primarily located via the master
    40 directory of each theory node (where the .thy file itself resides).
    41 The global load path is still partially available as legacy feature.
    42 Minor INCOMPATIBILITY due to subtle change in file lookup: use
    43 explicit paths, relatively to the theory.
    44 
    45 * Special treatment of ML file names has been discontinued.
    46 Historically, optional extensions .ML or .sml were added on demand --
    47 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
    48 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
    49 
    50 * Various options that affect pretty printing etc. are now properly
    51 handled within the context via configuration options, instead of
    52 unsynchronized references or print modes.  There are both ML Config.T
    53 entities and Isar declaration attributes to access these.
    54 
    55   ML (Config.T)                 Isar (attribute)
    56 
    57   eta_contract                  eta_contract
    58   show_brackets                 show_brackets
    59   show_sorts                    show_sorts
    60   show_types                    show_types
    61   show_question_marks           show_question_marks
    62   show_consts                   show_consts
    63   show_abbrevs                  show_abbrevs
    64 
    65   Syntax.ast_trace              syntax_ast_trace
    66   Syntax.ast_stat               syntax_ast_stat
    67   Syntax.ambiguity_level        syntax_ambiguity_level
    68 
    69   Goal_Display.goals_limit      goals_limit
    70   Goal_Display.show_main_goal   show_main_goal
    71 
    72   Method.rule_trace             rule_trace
    73 
    74   Thy_Output.display            thy_output_display
    75   Thy_Output.quotes             thy_output_quotes
    76   Thy_Output.indent             thy_output_indent
    77   Thy_Output.source             thy_output_source
    78   Thy_Output.break              thy_output_break
    79 
    80 Note that corresponding "..._default" references in ML may only be
    81 changed globally at the ROOT session setup, but *not* within a theory.
    82 The option "show_abbrevs" supersedes the former print mode
    83 "no_abbrevs" with inverted meaning.
    84 
    85 * More systematic naming of some configuration options.
    86 INCOMPATIBILITY.
    87 
    88   trace_simp  ~>  simp_trace
    89   debug_simp  ~>  simp_debug
    90 
    91 * Support for real valued configuration options, using simplistic
    92 floating-point notation that coincides with the inner syntax for
    93 float_token.
    94 
    95 * Support for real valued preferences (with approximative PGIP type):
    96 front-ends need to accept "pgint" values in float notation.
    97 INCOMPATIBILITY.
    98 
    99 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   100 DejaVu Sans.
   101 
   102 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   103 
   104 
   105 *** Pure ***
   106 
   107 * Command 'type_synonym' (with single argument) replaces somewhat
   108 outdated 'types', which is still available as legacy feature for some
   109 time.
   110 
   111 * Command 'nonterminal' (with 'and' separated list of arguments)
   112 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   113 
   114 * Command 'notepad' replaces former 'example_proof' for
   115 experimentation in Isar without any result.  INCOMPATIBILITY.
   116 
   117 * Locale interpretation commands 'interpret' and 'sublocale' accept
   118 lists of equations to map definitions in a locale to appropriate
   119 entities in the context of the interpretation.  The 'interpretation'
   120 command already provided this functionality.
   121 
   122 * Diagnostic command 'print_dependencies' prints the locale instances
   123 that would be activated if the specified expression was interpreted in
   124 the current context.  Variant "print_dependencies!" assumes a context
   125 without interpretations.
   126 
   127 * Diagnostic command 'print_interps' prints interpretations in proofs
   128 in addition to interpretations in theories.
   129 
   130 * Discontinued obsolete 'global' and 'local' commands to manipulate
   131 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   132 Sign.root_path and Sign.local_path may be applied directly where this
   133 feature is still required for historical reasons.
   134 
   135 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   136 'definition' instead.
   137 
   138 * The "prems" fact, which refers to the accidental collection of
   139 foundational premises in the context, is now explicitly marked as
   140 legacy feature and will be discontinued soon.  Consider using "assms"
   141 of the head statement or reference facts by explicit names.
   142 
   143 * Document antiquotations @{class} and @{type} print classes and type
   144 constructors.
   145 
   146 * Document antiquotation @{file} checks file/directory entries within
   147 the local file system.
   148 
   149 
   150 *** HOL ***
   151 
   152 * Coercive subtyping: functions can be declared as coercions and type
   153 inference will add them as necessary upon input of a term.  Theory
   154 Complex_Main declares real :: nat => real and real :: int => real as
   155 coercions. A coercion function f is declared like this:
   156 
   157   declare [[coercion f]]
   158 
   159 To lift coercions through type constructors (e.g. from nat => real to
   160 nat list => real list), map functions can be declared, e.g.
   161 
   162   declare [[coercion_map map]]
   163 
   164 Currently coercion inference is activated only in theories including
   165 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   166 the configuration option "coercion_enabled", e.g. it can be enabled in
   167 other theories like this:
   168 
   169   declare [[coercion_enabled]]
   170 
   171 * Command 'partial_function' provides basic support for recursive
   172 function definitions over complete partial orders.  Concrete instances
   173 are provided for i) the option type, ii) tail recursion on arbitrary
   174 types, and iii) the heap monad of Imperative_HOL.  See
   175 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   176 for examples.
   177 
   178 * Function package: f.psimps rules are no longer implicitly declared
   179 as [simp].  INCOMPATIBILITY.
   180 
   181 * Datatype package: theorems generated for executable equality (class
   182 "eq") carry proper names and are treated as default code equations.
   183 
   184 * Inductive package: now offers command 'inductive_simps' to
   185 automatically derive instantiated and simplified equations for
   186 inductive predicates, similar to 'inductive_cases'.
   187 
   188 * Command 'enriched_type' allows to register properties of the
   189 functorial structure of types.
   190 
   191 * Improved infrastructure for term evaluation using code generator
   192 techniques, in particular static evaluation conversions.
   193 
   194 * Code generator: Scala (2.8 or higher) has been added to the target
   195 languages.
   196 
   197 * Code generator: globbing constant expressions "*" and "Theory.*"
   198 have been replaced by the more idiomatic "_" and "Theory._".
   199 INCOMPATIBILITY.
   200 
   201 * Code generator: export_code without explicit file declaration prints
   202 to standard output.  INCOMPATIBILITY.
   203 
   204 * Code generator: do not print function definitions for case
   205 combinators any longer.
   206 
   207 * Code generator: simplification with rules determined with
   208 src/Tools/Code/code_simp.ML and method "code_simp".
   209 
   210 * Code generator for records: more idiomatic representation of record
   211 types.  Warning: records are not covered by ancient SML code
   212 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   213 rep_datatype declaration helps to succeed then:
   214 
   215   record 'a foo = ...
   216   ...
   217   rep_datatype foo_ext ...
   218 
   219 * Records: logical foundation type for records does not carry a
   220 '_type' suffix any longer (obsolete due to authentic syntax).
   221 INCOMPATIBILITY.
   222 
   223 * Quickcheck now by default uses exhaustive testing instead of random
   224 testing.  Random testing can be invoked by "quickcheck [random]",
   225 exhaustive testing by "quickcheck [exhaustive]".
   226 
   227 * Quickcheck instantiates polymorphic types with small finite
   228 datatypes by default. This enables a simple execution mechanism to
   229 handle quantifiers and function equality over the finite datatypes.
   230 
   231 * Quickcheck random generator has been renamed from "code" to
   232 "random".  INCOMPATIBILITY.
   233 
   234 * Quickcheck now has a configurable time limit which is set to 30
   235 seconds by default. This can be changed by adding [timeout = n] to the
   236 quickcheck command. The time limit for Auto Quickcheck is still set
   237 independently.
   238 
   239 * Quickcheck in locales considers interpretations of that locale for
   240 counter example search.
   241 
   242 * Sledgehammer:
   243   - Added "smt" and "remote_smt" provers based on the "smt" proof
   244     method. See the Sledgehammer manual for details ("isabelle doc
   245     sledgehammer").
   246   - Renamed commands:
   247     sledgehammer atp_info ~> sledgehammer running_provers
   248     sledgehammer atp_kill ~> sledgehammer kill_provers
   249     sledgehammer available_atps ~> sledgehammer available_provers
   250     INCOMPATIBILITY.
   251   - Renamed options:
   252     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   253     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   254     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   255     (and "ms" and "min" are no longer supported)
   256     INCOMPATIBILITY.
   257 
   258 * Nitpick:
   259   - Renamed options:
   260     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   261     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   262     INCOMPATIBILITY.
   263   - Added support for partial quotient types.
   264   - Added local versions of the "Nitpick.register_xxx" functions.
   265   - Added "whack" option.
   266   - Allow registration of quotient types as codatatypes.
   267   - Improved "merge_type_vars" option to merge more types.
   268   - Removed unsound "fast_descrs" option.
   269   - Added custom symmetry breaking for datatypes, making it possible to reach
   270     higher cardinalities.
   271   - Prevent the expansion of too large definitions.
   272 
   273 * Proof methods "metis" and "meson" now have configuration options
   274 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   275 to diagnose these tools. E.g.
   276 
   277     using [[metis_trace = true]]
   278 
   279 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   280 manually as command 'solve_direct'.
   281 
   282 * The default SMT solver is now CVC3.  Z3 must be enabled explicitly
   283 (due to licensing issues) via Z3_NON_COMMERCIAL in etc/settings of the
   284 component, for example.
   285 
   286 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   287 i.e. "remote_cvc3" and "remote_z3".
   288 
   289 * Added basic SMT support for datatypes, records, and typedefs using
   290 the oracle mode (no proofs).  Direct support of pairs has been dropped
   291 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   292 support for a similar behavior).  Minor INCOMPATIBILITY.
   293 
   294 * Changed SMT configuration options:
   295   - Renamed:
   296     z3_proofs ~> smt_oracle (with inverted meaning)
   297     z3_trace_assms ~> smt_trace_used_facts
   298     INCOMPATIBILITY.
   299   - Added:
   300     smt_verbose
   301     smt_random_seed
   302     smt_datatypes
   303     smt_infer_triggers
   304     smt_monomorph_limit
   305     cvc3_options
   306     remote_cvc3_options
   307     remote_z3_options
   308     yices_options
   309 
   310 * Boogie output files (.b2i files) need to be declared in the theory
   311 header.
   312 
   313 * Simplification procedure "list_to_set_comprehension" rewrites list
   314 comprehensions applied to List.set to set comprehensions.  Occasional
   315 INCOMPATIBILITY, may be deactivated like this:
   316 
   317   declare [[simproc del: list_to_set_comprehension]]
   318 
   319 * Removed old version of primrec package.  INCOMPATIBILITY.
   320 
   321 * Removed simplifier congruence rule of "prod_case", as has for long
   322 been the case with "split".  INCOMPATIBILITY.
   323 
   324 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   325 
   326 * Removed [split_format ... and ... and ...] version of
   327 [split_format].  Potential INCOMPATIBILITY.
   328 
   329 * Predicate "sorted" now defined inductively, with nice induction
   330 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   331 
   332 * Constant "contents" renamed to "the_elem", to free the generic name
   333 contents for other uses.  INCOMPATIBILITY.
   334 
   335 * Renamed class eq and constant eq (for code generation) to class
   336 equal and constant equal, plus renaming of related facts and various
   337 tuning.  INCOMPATIBILITY.
   338 
   339 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   340 
   341 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   342 INCOMPATIBILITY.
   343 
   344 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   345 avoid confusion with finite sets.  INCOMPATIBILITY.
   346 
   347 * Abandoned locales equiv, congruent and congruent2 for equivalence
   348 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   349 for congruent(2)).
   350 
   351 * Some previously unqualified names have been qualified:
   352 
   353   types
   354     bool ~> HOL.bool
   355     nat ~> Nat.nat
   356 
   357   constants
   358     Trueprop ~> HOL.Trueprop
   359     True ~> HOL.True
   360     False ~> HOL.False
   361     op & ~> HOL.conj
   362     op | ~> HOL.disj
   363     op --> ~> HOL.implies
   364     op = ~> HOL.eq
   365     Not ~> HOL.Not
   366     The ~> HOL.The
   367     All ~> HOL.All
   368     Ex ~> HOL.Ex
   369     Ex1 ~> HOL.Ex1
   370     Let ~> HOL.Let
   371     If ~> HOL.If
   372     Ball ~> Set.Ball
   373     Bex ~> Set.Bex
   374     Suc ~> Nat.Suc
   375     Pair ~> Product_Type.Pair
   376     fst ~> Product_Type.fst
   377     snd ~> Product_Type.snd
   378     curry ~> Product_Type.curry
   379     op : ~> Set.member
   380     Collect ~> Set.Collect
   381 
   382 INCOMPATIBILITY.
   383 
   384 * More canonical naming convention for some fundamental definitions:
   385 
   386     bot_bool_eq ~> bot_bool_def
   387     top_bool_eq ~> top_bool_def
   388     inf_bool_eq ~> inf_bool_def
   389     sup_bool_eq ~> sup_bool_def
   390     bot_fun_eq  ~> bot_fun_def
   391     top_fun_eq  ~> top_fun_def
   392     inf_fun_eq  ~> inf_fun_def
   393     sup_fun_eq  ~> sup_fun_def
   394 
   395 INCOMPATIBILITY.
   396 
   397 * More stylized fact names:
   398 
   399   expand_fun_eq ~> fun_eq_iff
   400   expand_set_eq ~> set_eq_iff
   401   set_ext       ~> set_eqI
   402   nat_number    ~> eval_nat_numeral
   403 
   404 INCOMPATIBILITY.
   405 
   406 * Refactoring of code-generation specific operations in theory List:
   407 
   408   constants
   409     null ~> List.null
   410 
   411   facts
   412     mem_iff ~> member_def
   413     null_empty ~> null_def
   414 
   415 INCOMPATIBILITY.  Note that these were not supposed to be used
   416 regularly unless for striking reasons; their main purpose was code
   417 generation.
   418 
   419 Various operations from the Haskell prelude are used for generating
   420 Haskell code.
   421 
   422 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   423 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   424 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   425 
   426 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   427 "*" and "+" respectively.  INCOMPATIBILITY.
   428 
   429 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   430 "Sum_Type.Plus" instead.
   431 
   432 * Constant "split" has been merged with constant "prod_case"; names of
   433 ML functions, facts etc. involving split have been retained so far,
   434 though.  INCOMPATIBILITY.
   435 
   436 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   437 instead.  INCOMPATIBILITY.
   438 
   439 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   440 INCOMPATIBILITY.
   441 
   442 * Former theory Library/Enum is now part of the HOL-Main image.
   443 INCOMPATIBILITY: all constants of the Enum theory now have to be
   444 referred to by its qualified name.
   445 
   446   enum    ~>  Enum.enum
   447   nlists  ~>  Enum.nlists
   448   product ~>  Enum.product
   449 
   450 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   451 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   452 INCOMPATIBILITY.
   453 
   454 * Theory Library/SetsAndFunctions has been split into
   455 Library/Function_Algebras and Library/Set_Algebras; canonical names
   456 for instance definitions for functions; various improvements.
   457 INCOMPATIBILITY.
   458 
   459 * Theory Library/Multiset provides stable quicksort implementation of
   460 sort_key.
   461 
   462 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   463 INCOMPATIBILITY.
   464 
   465 * Session Multivariate_Analysis: introduced a type class for euclidean
   466 space.  Most theorems are now stated in terms of euclidean spaces
   467 instead of finite cartesian products.
   468 
   469   types
   470     real ^ 'n ~>  'a::real_vector
   471               ~>  'a::euclidean_space
   472               ~>  'a::ordered_euclidean_space
   473         (depends on your needs)
   474 
   475   constants
   476      _ $ _        ~> _ $$ _
   477      \<chi> x. _  ~> \<chi>\<chi> x. _
   478      CARD('n)     ~> DIM('a)
   479 
   480 Also note that the indices are now natural numbers and not from some
   481 finite type. Finite cartesian products of euclidean spaces, products
   482 of euclidean spaces the real and complex numbers are instantiated to
   483 be euclidean_spaces.  INCOMPATIBILITY.
   484 
   485 * Session Probability: introduced pextreal as positive extended real
   486 numbers.  Use pextreal as value for measures.  Introduce the
   487 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   488 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   489 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   490 
   491 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   492 INCOMPATIBILITY.
   493 
   494 * Session SPARK (with image HOL-SPARK) provides commands to load and
   495 prove verification conditions generated by the SPARK Ada program
   496 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   497 
   498 
   499 *** HOL-Algebra ***
   500 
   501 * Theorems for additive ring operations (locale abelian_monoid and
   502 descendants) are generated by interpretation from their multiplicative
   503 counterparts.  Names (in particular theorem names) have the mandatory
   504 qualifier 'add'.  Previous theorem names are redeclared for
   505 compatibility.
   506 
   507 * Structure "int_ring" is now an abbreviation (previously a
   508 definition).  This fits more natural with advanced interpretations.
   509 
   510 
   511 *** HOLCF ***
   512 
   513 * The domain package now runs in definitional mode by default: The
   514 former command 'new_domain' is now called 'domain'.  To use the domain
   515 package in its original axiomatic mode, use 'domain (unsafe)'.
   516 INCOMPATIBILITY.
   517 
   518 * The new class "domain" is now the default sort.  Class "predomain"
   519 is an unpointed version of "domain". Theories can be updated by
   520 replacing sort annotations as shown below.  INCOMPATIBILITY.
   521 
   522   'a::type ~> 'a::countable
   523   'a::cpo  ~> 'a::predomain
   524   'a::pcpo ~> 'a::domain
   525 
   526 * The old type class "rep" has been superseded by class "domain".
   527 Accordingly, users of the definitional package must remove any
   528 "default_sort rep" declarations.  INCOMPATIBILITY.
   529 
   530 * The domain package (definitional mode) now supports unpointed
   531 predomain argument types, as long as they are marked 'lazy'. (Strict
   532 arguments must be in class "domain".) For example, the following
   533 domain definition now works:
   534 
   535   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   536 
   537 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   538 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   539 'a option, and 'a list.  Additionally, it configures fixrec and the
   540 domain package to work with these types.  For example:
   541 
   542   fixrec isInl :: "('a + 'b) u -> tr"
   543     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   544 
   545   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   546 
   547 * The "(permissive)" option of fixrec has been replaced with a
   548 per-equation "(unchecked)" option. See
   549 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
   550 
   551 * The "bifinite" class no longer fixes a constant "approx"; the class
   552 now just asserts that such a function exists.  INCOMPATIBILITY.
   553 
   554 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
   555 defines an embedding of type 'a defl into udom by default; instances
   556 of "bifinite" and "domain" classes are available in
   557 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
   558 
   559 * The syntax "REP('a)" has been replaced with "DEFL('a)".
   560 
   561 * The predicate "directed" has been removed.  INCOMPATIBILITY.
   562 
   563 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
   564 
   565 * The function "cprod_map" has been renamed to "prod_map".
   566 INCOMPATIBILITY.
   567 
   568 * The monadic bind operator on each powerdomain has new binder syntax
   569 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
   570 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
   571 
   572 * The infix syntax for binary union on each powerdomain has changed
   573 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
   574 syntax.  INCOMPATIBILITY.
   575 
   576 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
   577 still supported as an input translation.
   578 
   579 * Renamed some theorems (the original names are also still available).
   580 
   581   expand_fun_below   ~> fun_below_iff
   582   below_fun_ext      ~> fun_belowI
   583   expand_cfun_eq     ~> cfun_eq_iff
   584   ext_cfun           ~> cfun_eqI
   585   expand_cfun_below  ~> cfun_below_iff
   586   below_cfun_ext     ~> cfun_belowI
   587   cont2cont_Rep_CFun ~> cont2cont_APP
   588 
   589 * The Abs and Rep functions for various types have changed names.
   590 Related theorem names have also changed to match. INCOMPATIBILITY.
   591 
   592   Rep_CFun  ~> Rep_cfun
   593   Abs_CFun  ~> Abs_cfun
   594   Rep_Sprod ~> Rep_sprod
   595   Abs_Sprod ~> Abs_sprod
   596   Rep_Ssum  ~> Rep_ssum
   597   Abs_Ssum  ~> Abs_ssum
   598 
   599 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   600 been renamed to *_bottom_iff.  INCOMPATIBILITY.
   601 
   602 * Various changes to bisimulation/coinduction with domain package:
   603 
   604   - Definitions of "bisim" constants no longer mention definedness.
   605   - With mutual recursion, "bisim" predicate is now curried.
   606   - With mutual recursion, each type gets a separate coind theorem.
   607   - Variable names in bisim_def and coinduct rules have changed.
   608 
   609 INCOMPATIBILITY.
   610 
   611 * Case combinators generated by the domain package for type "foo" are
   612 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
   613 
   614 * Several theorems have been renamed to more accurately reflect the
   615 names of constants and types involved.  INCOMPATIBILITY.
   616 
   617   thelub_const    ~> lub_const
   618   lub_const       ~> is_lub_const
   619   thelubI         ~> lub_eqI
   620   is_lub_lub      ~> is_lubD2
   621   lubI            ~> is_lub_lub
   622   unique_lub      ~> is_lub_unique
   623   is_ub_lub       ~> is_lub_rangeD1
   624   lub_bin_chain   ~> is_lub_bin_chain
   625   lub_fun         ~> is_lub_fun
   626   thelub_fun      ~> lub_fun
   627   thelub_cfun     ~> lub_cfun
   628   thelub_Pair     ~> lub_Pair
   629   lub_cprod       ~> is_lub_prod
   630   thelub_cprod    ~> lub_prod
   631   minimal_cprod   ~> minimal_prod
   632   inst_cprod_pcpo ~> inst_prod_pcpo
   633   UU_I            ~> bottomI
   634   compact_UU      ~> compact_bottom
   635   deflation_UU    ~> deflation_bottom
   636   finite_deflation_UU ~> finite_deflation_bottom
   637 
   638 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
   639 
   640   sq_ord_less_eq_trans ~> below_eq_trans
   641   sq_ord_eq_less_trans ~> eq_below_trans
   642   refl_less            ~> below_refl
   643   trans_less           ~> below_trans
   644   antisym_less         ~> below_antisym
   645   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
   646   box_less             ~> box_below
   647   rev_trans_less       ~> rev_below_trans
   648   not_less2not_eq      ~> not_below2not_eq
   649   less_UU_iff          ~> below_UU_iff
   650   flat_less_iff        ~> flat_below_iff
   651   adm_less             ~> adm_below
   652   adm_not_less         ~> adm_not_below
   653   adm_compact_not_less ~> adm_compact_not_below
   654   less_fun_def         ~> below_fun_def
   655   expand_fun_less      ~> fun_below_iff
   656   less_fun_ext         ~> fun_belowI
   657   less_discr_def       ~> below_discr_def
   658   discr_less_eq        ~> discr_below_eq
   659   less_unit_def        ~> below_unit_def
   660   less_cprod_def       ~> below_prod_def
   661   prod_lessI           ~> prod_belowI
   662   Pair_less_iff        ~> Pair_below_iff
   663   fst_less_iff         ~> fst_below_iff
   664   snd_less_iff         ~> snd_below_iff
   665   expand_cfun_less     ~> cfun_below_iff
   666   less_cfun_ext        ~> cfun_belowI
   667   injection_less       ~> injection_below
   668   less_up_def          ~> below_up_def
   669   not_Iup_less         ~> not_Iup_below
   670   Iup_less             ~> Iup_below
   671   up_less              ~> up_below
   672   Def_inject_less_eq   ~> Def_below_Def
   673   Def_less_is_eq       ~> Def_below_iff
   674   spair_less_iff       ~> spair_below_iff
   675   less_sprod           ~> below_sprod
   676   spair_less           ~> spair_below
   677   sfst_less_iff        ~> sfst_below_iff
   678   ssnd_less_iff        ~> ssnd_below_iff
   679   fix_least_less       ~> fix_least_below
   680   dist_less_one        ~> dist_below_one
   681   less_ONE             ~> below_ONE
   682   ONE_less_iff         ~> ONE_below_iff
   683   less_sinlD           ~> below_sinlD
   684   less_sinrD           ~> below_sinrD
   685 
   686 
   687 *** FOL and ZF ***
   688 
   689 * All constant names are now qualified internally and use proper
   690 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
   691 
   692 
   693 *** ML ***
   694 
   695 * Antiquotation @{assert} inlines a function bool -> unit that raises
   696 Fail if the argument is false.  Due to inlining the source position of
   697 failed assertions is included in the error output.
   698 
   699 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
   700 text is in practice always evaluated with a stable theory checkpoint.
   701 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
   702 
   703 * Antiquotation @{theory A} refers to theory A from the ancestry of
   704 the current context, not any accidental theory loader state as before.
   705 Potential INCOMPATIBILITY, subtle change in semantics.
   706 
   707 * Syntax.pretty_priority (default 0) configures the required priority
   708 of pretty-printed output and thus affects insertion of parentheses.
   709 
   710 * Syntax.default_root (default "any") configures the inner syntax
   711 category (nonterminal symbol) for parsing of terms.
   712 
   713 * Former exception Library.UnequalLengths now coincides with
   714 ListPair.UnequalLengths.
   715 
   716 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
   717 main functionality is provided by structure Simplifier.
   718 
   719 * Renamed raw "explode" function to "raw_explode" to emphasize its
   720 meaning.  Note that internally to Isabelle, Symbol.explode is used in
   721 almost all situations.
   722 
   723 * Discontinued obsolete function sys_error and exception SYS_ERROR.
   724 See implementation manual for further details on exceptions in
   725 Isabelle/ML.
   726 
   727 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   728 meaning.
   729 
   730 * Renamed structure PureThy to Pure_Thy and moved most of its
   731 operations to structure Global_Theory, to emphasize that this is
   732 rarely-used global-only stuff.
   733 
   734 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
   735 instead (or tracing for high-volume output).
   736 
   737 * Configuration option show_question_marks only affects regular pretty
   738 printing of types and terms, not raw Term.string_of_vname.
   739 
   740 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
   741 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
   742 @{thms} for most purposes.
   743 
   744 * ML structure Unsynchronized is never opened, not even in Isar
   745 interaction mode as before.  Old Unsynchronized.set etc. have been
   746 discontinued -- use plain := instead.  This should be *rare* anyway,
   747 since modern tools always work via official context data, notably
   748 configuration options.
   749 
   750 * Parallel and asynchronous execution requires special care concerning
   751 interrupts.  Structure Exn provides some convenience functions that
   752 avoid working directly with raw Interrupt.  User code must not absorb
   753 interrupts -- intermediate handling (for cleanup etc.) needs to be
   754 followed by re-raising of the original exception.  Another common
   755 source of mistakes are "handle _" patterns, which make the meaning of
   756 the program subject to physical effects of the environment.
   757 
   758 
   759 
   760 New in Isabelle2009-2 (June 2010)
   761 ---------------------------------
   762 
   763 *** General ***
   764 
   765 * Authentic syntax for *all* logical entities (type classes, type
   766 constructors, term constants): provides simple and robust
   767 correspondence between formal entities and concrete syntax.  Within
   768 the parse tree / AST representations, "constants" are decorated by
   769 their category (class, type, const) and spelled out explicitly with
   770 their full internal name.
   771 
   772 Substantial INCOMPATIBILITY concerning low-level syntax declarations
   773 and translations (translation rules and translation functions in ML).
   774 Some hints on upgrading:
   775 
   776   - Many existing uses of 'syntax' and 'translations' can be replaced
   777     by more modern 'type_notation', 'notation' and 'abbreviation',
   778     which are independent of this issue.
   779 
   780   - 'translations' require markup within the AST; the term syntax
   781     provides the following special forms:
   782 
   783       CONST c   -- produces syntax version of constant c from context
   784       XCONST c  -- literally c, checked as constant from context
   785       c         -- literally c, if declared by 'syntax'
   786 
   787     Plain identifiers are treated as AST variables -- occasionally the
   788     system indicates accidental variables via the error "rhs contains
   789     extra variables".
   790 
   791     Type classes and type constructors are marked according to their
   792     concrete syntax.  Some old translations rules need to be written
   793     for the "type" category, using type constructor application
   794     instead of pseudo-term application of the default category
   795     "logic".
   796 
   797   - 'parse_translation' etc. in ML may use the following
   798     antiquotations:
   799 
   800       @{class_syntax c}   -- type class c within parse tree / AST
   801       @{term_syntax c}    -- type constructor c within parse tree / AST
   802       @{const_syntax c}   -- ML version of "CONST c" above
   803       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
   804 
   805   - Literal types within 'typed_print_translations', i.e. those *not*
   806     represented as pseudo-terms are represented verbatim.  Use @{class
   807     c} or @{type_name c} here instead of the above syntax
   808     antiquotations.
   809 
   810 Note that old non-authentic syntax was based on unqualified base
   811 names, so all of the above "constant" names would coincide.  Recall
   812 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
   813 diagnose syntax problems.
   814 
   815 * Type constructors admit general mixfix syntax, not just infix.
   816 
   817 * Concrete syntax may be attached to local entities without a proof
   818 body, too.  This works via regular mixfix annotations for 'fix',
   819 'def', 'obtain' etc. or via the explicit 'write' command, which is
   820 similar to the 'notation' command in theory specifications.
   821 
   822 * Discontinued unnamed infix syntax (legacy feature for many years) --
   823 need to specify constant name and syntax separately.  Internal ML
   824 datatype constructors have been renamed from InfixName to Infix etc.
   825 Minor INCOMPATIBILITY.
   826 
   827 * Schematic theorem statements need to be explicitly markup as such,
   828 via commands 'schematic_lemma', 'schematic_theorem',
   829 'schematic_corollary'.  Thus the relevance of the proof is made
   830 syntactically clear, which impacts performance in a parallel or
   831 asynchronous interactive environment.  Minor INCOMPATIBILITY.
   832 
   833 * Use of cumulative prems via "!" in some proof methods has been
   834 discontinued (old legacy feature).
   835 
   836 * References 'trace_simp' and 'debug_simp' have been replaced by
   837 configuration options stored in the context. Enabling tracing (the
   838 case of debugging is similar) in proofs works via
   839 
   840   using [[trace_simp = true]]
   841 
   842 Tracing is then active for all invocations of the simplifier in
   843 subsequent goal refinement steps. Tracing may also still be enabled or
   844 disabled via the ProofGeneral settings menu.
   845 
   846 * Separate commands 'hide_class', 'hide_type', 'hide_const',
   847 'hide_fact' replace the former 'hide' KIND command.  Minor
   848 INCOMPATIBILITY.
   849 
   850 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
   851 more efficient than combinations with -q1 or -q2.
   852 
   853 
   854 *** Pure ***
   855 
   856 * Proofterms record type-class reasoning explicitly, using the
   857 "unconstrain" operation internally.  This eliminates all sort
   858 constraints from a theorem and proof, introducing explicit
   859 OFCLASS-premises.  On the proof term level, this operation is
   860 automatically applied at theorem boundaries, such that closed proofs
   861 are always free of sort constraints.  INCOMPATIBILITY for tools that
   862 inspect proof terms.
   863 
   864 * Local theory specifications may depend on extra type variables that
   865 are not present in the result type -- arguments TYPE('a) :: 'a itself
   866 are added internally.  For example:
   867 
   868   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
   869 
   870 * Predicates of locales introduced by classes carry a mandatory
   871 "class" prefix.  INCOMPATIBILITY.
   872 
   873 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
   874 
   875 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
   876 'class' instead.
   877 
   878 * Command 'code_reflect' allows to incorporate generated ML code into
   879 runtime environment; replaces immature code_datatype antiquotation.
   880 INCOMPATIBILITY.
   881 
   882 * Code generator: simple concept for abstract datatypes obeying
   883 invariants.
   884 
   885 * Code generator: details of internal data cache have no impact on the
   886 user space functionality any longer.
   887 
   888 * Methods "unfold_locales" and "intro_locales" ignore non-locale
   889 subgoals.  This is more appropriate for interpretations with 'where'.
   890 INCOMPATIBILITY.
   891 
   892 * Command 'example_proof' opens an empty proof body.  This allows to
   893 experiment with Isar, without producing any persistent result.
   894 
   895 * Commands 'type_notation' and 'no_type_notation' declare type syntax
   896 within a local theory context, with explicit checking of the
   897 constructors involved (in contrast to the raw 'syntax' versions).
   898 
   899 * Commands 'types' and 'typedecl' now work within a local theory
   900 context -- without introducing dependencies on parameters or
   901 assumptions, which is not possible in Isabelle/Pure.
   902 
   903 * Command 'defaultsort' has been renamed to 'default_sort', it works
   904 within a local theory context.  Minor INCOMPATIBILITY.
   905 
   906 
   907 *** HOL ***
   908 
   909 * Command 'typedef' now works within a local theory context -- without
   910 introducing dependencies on parameters or assumptions, which is not
   911 possible in Isabelle/Pure/HOL.  Note that the logical environment may
   912 contain multiple interpretations of local typedefs (with different
   913 non-emptiness proofs), even in a global theory context.
   914 
   915 * New package for quotient types.  Commands 'quotient_type' and
   916 'quotient_definition' may be used for defining types and constants by
   917 quotient constructions.  An example is the type of integers created by
   918 quotienting pairs of natural numbers:
   919 
   920   fun
   921     intrel :: "(nat * nat) => (nat * nat) => bool"
   922   where
   923     "intrel (x, y) (u, v) = (x + v = u + y)"
   924 
   925   quotient_type int = "nat * nat" / intrel
   926     by (auto simp add: equivp_def expand_fun_eq)
   927 
   928   quotient_definition
   929     "0::int" is "(0::nat, 0::nat)"
   930 
   931 The method "lifting" can be used to lift of theorems from the
   932 underlying "raw" type to the quotient type.  The example
   933 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
   934 construction and provides a reasoning infrastructure for finite sets.
   935 
   936 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
   937 clash with new theory Quotient in Main HOL.
   938 
   939 * Moved the SMT binding into the main HOL session, eliminating
   940 separate HOL-SMT session.
   941 
   942 * List membership infix mem operation is only an input abbreviation.
   943 INCOMPATIBILITY.
   944 
   945 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
   946 for future developements; former Library/Word.thy is still present in
   947 the AFP entry RSAPPS.
   948 
   949 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
   950 longer shadowed.  INCOMPATIBILITY.
   951 
   952 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
   953 INCOMPATIBILITY.
   954 
   955 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
   956 INCOMPATIBILITY.
   957 
   958 * Dropped normalizing_semiring etc; use the facts in semiring classes
   959 instead.  INCOMPATIBILITY.
   960 
   961 * Dropped several real-specific versions of lemmas about floor and
   962 ceiling; use the generic lemmas from theory "Archimedean_Field"
   963 instead.  INCOMPATIBILITY.
   964 
   965   floor_number_of_eq         ~> floor_number_of
   966   le_floor_eq_number_of      ~> number_of_le_floor
   967   le_floor_eq_zero           ~> zero_le_floor
   968   le_floor_eq_one            ~> one_le_floor
   969   floor_less_eq_number_of    ~> floor_less_number_of
   970   floor_less_eq_zero         ~> floor_less_zero
   971   floor_less_eq_one          ~> floor_less_one
   972   less_floor_eq_number_of    ~> number_of_less_floor
   973   less_floor_eq_zero         ~> zero_less_floor
   974   less_floor_eq_one          ~> one_less_floor
   975   floor_le_eq_number_of      ~> floor_le_number_of
   976   floor_le_eq_zero           ~> floor_le_zero
   977   floor_le_eq_one            ~> floor_le_one
   978   floor_subtract_number_of   ~> floor_diff_number_of
   979   floor_subtract_one         ~> floor_diff_one
   980   ceiling_number_of_eq       ~> ceiling_number_of
   981   ceiling_le_eq_number_of    ~> ceiling_le_number_of
   982   ceiling_le_zero_eq         ~> ceiling_le_zero
   983   ceiling_le_eq_one          ~> ceiling_le_one
   984   less_ceiling_eq_number_of  ~> number_of_less_ceiling
   985   less_ceiling_eq_zero       ~> zero_less_ceiling
   986   less_ceiling_eq_one        ~> one_less_ceiling
   987   ceiling_less_eq_number_of  ~> ceiling_less_number_of
   988   ceiling_less_eq_zero       ~> ceiling_less_zero
   989   ceiling_less_eq_one        ~> ceiling_less_one
   990   le_ceiling_eq_number_of    ~> number_of_le_ceiling
   991   le_ceiling_eq_zero         ~> zero_le_ceiling
   992   le_ceiling_eq_one          ~> one_le_ceiling
   993   ceiling_subtract_number_of ~> ceiling_diff_number_of
   994   ceiling_subtract_one       ~> ceiling_diff_one
   995 
   996 * Theory "Finite_Set": various folding_XXX locales facilitate the
   997 application of the various fold combinators on finite sets.
   998 
   999 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1000 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1001 implementation.  INCOMPATIBILTY.
  1002 
  1003 * Theory Library/Coinductive_List has been removed -- superseded by
  1004 AFP/thys/Coinductive.
  1005 
  1006 * Theory PReal, including the type "preal" and related operations, has
  1007 been removed.  INCOMPATIBILITY.
  1008 
  1009 * Real: new development using Cauchy Sequences.
  1010 
  1011 * Split off theory "Big_Operators" containing setsum, setprod,
  1012 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1013 
  1014 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1015 "Int" etc.  INCOMPATIBILITY.
  1016 
  1017 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1018 
  1019 * New set of rules "ac_simps" provides combined assoc / commute
  1020 rewrites for all interpretations of the appropriate generic locales.
  1021 
  1022 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1023 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1024 appropriate and more consistent names suitable for name prefixes
  1025 within the HOL theories.  INCOMPATIBILITY.
  1026 
  1027 * Some generic constants have been put to appropriate theories:
  1028   - less_eq, less: Orderings
  1029   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1030   - inverse, divide: Rings
  1031 INCOMPATIBILITY.
  1032 
  1033 * More consistent naming of type classes involving orderings (and
  1034 lattices):
  1035 
  1036     lower_semilattice                   ~> semilattice_inf
  1037     upper_semilattice                   ~> semilattice_sup
  1038 
  1039     dense_linear_order                  ~> dense_linorder
  1040 
  1041     pordered_ab_group_add               ~> ordered_ab_group_add
  1042     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1043     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1044     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1045     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1046     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1047     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1048     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1049     pordered_comm_ring                  ~> ordered_comm_ring
  1050     pordered_comm_semiring              ~> ordered_comm_semiring
  1051     pordered_ring                       ~> ordered_ring
  1052     pordered_ring_abs                   ~> ordered_ring_abs
  1053     pordered_semiring                   ~> ordered_semiring
  1054 
  1055     ordered_ab_group_add                ~> linordered_ab_group_add
  1056     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1057     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1058     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1059     ordered_field                       ~> linordered_field
  1060     ordered_field_no_lb                 ~> linordered_field_no_lb
  1061     ordered_field_no_ub                 ~> linordered_field_no_ub
  1062     ordered_field_dense_linear_order    ~> dense_linordered_field
  1063     ordered_idom                        ~> linordered_idom
  1064     ordered_ring                        ~> linordered_ring
  1065     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1066     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1067     ordered_ring_strict                 ~> linordered_ring_strict
  1068     ordered_semidom                     ~> linordered_semidom
  1069     ordered_semiring                    ~> linordered_semiring
  1070     ordered_semiring_1                  ~> linordered_semiring_1
  1071     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1072     ordered_semiring_strict             ~> linordered_semiring_strict
  1073 
  1074   The following slightly odd type classes have been moved to a
  1075   separate theory Library/Lattice_Algebras:
  1076 
  1077     lordered_ab_group_add               ~> lattice_ab_group_add
  1078     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1079     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1080     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1081     lordered_ring                       ~> lattice_ring
  1082 
  1083 INCOMPATIBILITY.
  1084 
  1085 * Refined field classes:
  1086   - classes division_ring_inverse_zero, field_inverse_zero,
  1087     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1088     subsumes former division_by_zero class;
  1089   - numerous lemmas have been ported from field to division_ring.
  1090 INCOMPATIBILITY.
  1091 
  1092 * Refined algebra theorem collections:
  1093   - dropped theorem group group_simps, use algebra_simps instead;
  1094   - dropped theorem group ring_simps, use field_simps instead;
  1095   - proper theorem collection field_simps subsumes former theorem
  1096     groups field_eq_simps and field_simps;
  1097   - dropped lemma eq_minus_self_iff which is a duplicate for
  1098     equal_neg_zero.
  1099 INCOMPATIBILITY.
  1100 
  1101 * Theory Finite_Set and List: some lemmas have been generalized from
  1102 sets to lattices:
  1103 
  1104   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1105   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1106   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1107   union_Union_fold_union        ~> sup_Sup_fold_sup
  1108   Inter_fold_inter              ~> Inf_fold_inf
  1109   Union_fold_union              ~> Sup_fold_sup
  1110   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1111   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1112   INTER_fold_inter              ~> INFI_fold_inf
  1113   UNION_fold_union              ~> SUPR_fold_sup
  1114 
  1115 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1116 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1117 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1118 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1119 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1120 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1121 
  1122 * Reorganized theory Multiset: swapped notation of pointwise and
  1123 multiset order:
  1124 
  1125   - pointwise ordering is instance of class order with standard syntax
  1126     <= and <;
  1127   - multiset ordering has syntax <=# and <#; partial order properties
  1128     are provided by means of interpretation with prefix
  1129     multiset_order;
  1130   - less duplication, less historical organization of sections,
  1131     conversion from associations lists to multisets, rudimentary code
  1132     generation;
  1133   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1134     if needed.
  1135 
  1136 Renamed:
  1137 
  1138   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1139   multi_count_ext  ~>  multiset_ext
  1140   diff_union_inverse2  ~>  diff_union_cancelR
  1141 
  1142 INCOMPATIBILITY.
  1143 
  1144 * Theory Permutation: replaced local "remove" by List.remove1.
  1145 
  1146 * Code generation: ML and OCaml code is decorated with signatures.
  1147 
  1148 * Theory List: added transpose.
  1149 
  1150 * Library/Nat_Bijection.thy is a collection of bijective functions
  1151 between nat and other types, which supersedes the older libraries
  1152 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1153 
  1154   Constants:
  1155   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1156   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1157   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1158   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1159   Countable.pair_encode           ~> prod_encode
  1160   NatIso.prod2nat                 ~> prod_encode
  1161   NatIso.nat2prod                 ~> prod_decode
  1162   NatIso.sum2nat                  ~> sum_encode
  1163   NatIso.nat2sum                  ~> sum_decode
  1164   NatIso.list2nat                 ~> list_encode
  1165   NatIso.nat2list                 ~> list_decode
  1166   NatIso.set2nat                  ~> set_encode
  1167   NatIso.nat2set                  ~> set_decode
  1168 
  1169   Lemmas:
  1170   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1171   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1172   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1173   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1174   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1175   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1176   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1177   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1178   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1179   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1180   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1181   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1182   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1183 
  1184 * Sledgehammer:
  1185   - Renamed ATP commands:
  1186     atp_info     ~> sledgehammer running_atps
  1187     atp_kill     ~> sledgehammer kill_atps
  1188     atp_messages ~> sledgehammer messages
  1189     atp_minimize ~> sledgehammer minimize
  1190     print_atps   ~> sledgehammer available_atps
  1191     INCOMPATIBILITY.
  1192   - Added user's manual ("isabelle doc sledgehammer").
  1193   - Added option syntax and "sledgehammer_params" to customize
  1194     Sledgehammer's behavior.  See the manual for details.
  1195   - Modified the Isar proof reconstruction code so that it produces
  1196     direct proofs rather than proofs by contradiction.  (This feature
  1197     is still experimental.)
  1198   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1199     full-typed mode.
  1200   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1201 
  1202 * Nitpick:
  1203   - Added and implemented "binary_ints" and "bits" options.
  1204   - Added "std" option and implemented support for nonstandard models.
  1205   - Added and implemented "finitize" option to improve the precision
  1206     of infinite datatypes based on a monotonicity analysis.
  1207   - Added support for quotient types.
  1208   - Added support for "specification" and "ax_specification"
  1209     constructs.
  1210   - Added support for local definitions (for "function" and
  1211     "termination" proofs).
  1212   - Added support for term postprocessors.
  1213   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1214   - Improved efficiency of "destroy_constrs" optimization.
  1215   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1216     record getters.
  1217   - Fixed soundness bug related to higher-order constructors.
  1218   - Fixed soundness bug when "full_descrs" is enabled.
  1219   - Improved precision of set constructs.
  1220   - Added "atoms" option.
  1221   - Added cache to speed up repeated Kodkod invocations on the same
  1222     problems.
  1223   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1224     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1225     "SAT4J_Light".  INCOMPATIBILITY.
  1226   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1227     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1228   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1229 
  1230 * Method "induct" now takes instantiations of the form t, where t is not
  1231   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1232   If this is not intended, t has to be enclosed in parentheses.
  1233   By default, the equalities generated by definitional instantiations
  1234   are pre-simplified, which may cause parameters of inductive cases
  1235   to disappear, or may even delete some of the inductive cases.
  1236   Use "induct (no_simp)" instead of "induct" to restore the old
  1237   behaviour. The (no_simp) option is also understood by the "cases"
  1238   and "nominal_induct" methods, which now perform pre-simplification, too.
  1239   INCOMPATIBILITY.
  1240 
  1241 
  1242 *** HOLCF ***
  1243 
  1244 * Variable names in lemmas generated by the domain package have
  1245 changed; the naming scheme is now consistent with the HOL datatype
  1246 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1247 
  1248 * The domain package no longer defines the function "foo_copy" for
  1249 recursive domain "foo".  The reach lemma is now stated directly in
  1250 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1251 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1252 
  1253 * Most definedness lemmas generated by the domain package (previously
  1254 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1255 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1256 Proofs that used definedness lemmas as intro rules may break,
  1257 potential INCOMPATIBILITY.
  1258 
  1259 * Induction and casedist rules generated by the domain package now
  1260 declare proper case_names (one called "bottom", and one named for each
  1261 constructor).  INCOMPATIBILITY.
  1262 
  1263 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1264 rules are generated for each domain, INCOMPATIBILITY.
  1265 
  1266   foo_bar.reach       ~> foo.reach  bar.reach
  1267   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1268 
  1269 * Some lemmas generated by the domain package have been renamed for
  1270 consistency with the datatype package, INCOMPATIBILITY.
  1271 
  1272   foo.ind        ~> foo.induct
  1273   foo.finite_ind ~> foo.finite_induct
  1274   foo.coind      ~> foo.coinduct
  1275   foo.casedist   ~> foo.exhaust
  1276   foo.exhaust    ~> foo.nchotomy
  1277 
  1278 * For consistency with other definition packages, the fixrec package
  1279 now generates qualified theorem names, INCOMPATIBILITY.
  1280 
  1281   foo_simps  ~> foo.simps
  1282   foo_unfold ~> foo.unfold
  1283   foo_induct ~> foo.induct
  1284 
  1285 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1286 method and internal fixrec proofs now use the default simpset instead.
  1287 INCOMPATIBILITY.
  1288 
  1289 * The "contlub" predicate has been removed.  Proof scripts should use
  1290 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1291 
  1292 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1293 
  1294 * The constants cpair, cfst, and csnd have been removed in favor of
  1295 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1296 
  1297 
  1298 *** ML ***
  1299 
  1300 * Antiquotations for basic formal entities:
  1301 
  1302     @{class NAME}         -- type class
  1303     @{class_syntax NAME}  -- syntax representation of the above
  1304 
  1305     @{type_name NAME}     -- logical type
  1306     @{type_abbrev NAME}   -- type abbreviation
  1307     @{nonterminal NAME}   -- type of concrete syntactic category
  1308     @{type_syntax NAME}   -- syntax representation of any of the above
  1309 
  1310     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1311     @{const_abbrev NAME}  -- abbreviated constant
  1312     @{const_syntax NAME}  -- syntax representation of any of the above
  1313 
  1314 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1315 syntax constant (cf. 'syntax' command).
  1316 
  1317 * Antiquotation @{make_string} inlines a function to print arbitrary
  1318 values similar to the ML toplevel.  The result is compiler dependent
  1319 and may fall back on "?" in certain situations.
  1320 
  1321 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1322 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1323 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1324 not work with the asynchronous Isar document model.
  1325 
  1326 * Configuration options now admit dynamic default values, depending on
  1327 the context or even global references.
  1328 
  1329 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1330 uses an efficient external library if available (for Poly/ML).
  1331 
  1332 * Renamed some important ML structures, while keeping the old names
  1333 for some time as aliases within the structure Legacy:
  1334 
  1335   OuterKeyword  ~>  Keyword
  1336   OuterLex      ~>  Token
  1337   OuterParse    ~>  Parse
  1338   OuterSyntax   ~>  Outer_Syntax
  1339   PrintMode     ~>  Print_Mode
  1340   SpecParse     ~>  Parse_Spec
  1341   ThyInfo       ~>  Thy_Info
  1342   ThyLoad       ~>  Thy_Load
  1343   ThyOutput     ~>  Thy_Output
  1344   TypeInfer     ~>  Type_Infer
  1345 
  1346 Note that "open Legacy" simplifies porting of sources, but forgetting
  1347 to remove it again will complicate porting again in the future.
  1348 
  1349 * Most operations that refer to a global context are named
  1350 accordingly, e.g. Simplifier.global_context or
  1351 ProofContext.init_global.  There are some situations where a global
  1352 context actually works, but under normal circumstances one needs to
  1353 pass the proper local context through the code!
  1354 
  1355 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1356 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1357 Pretty.pp argument to merge, which is absent in the standard
  1358 Theory_Data version.
  1359 
  1360 * Sorts.certify_sort and derived "cert" operations for types and terms
  1361 no longer minimize sorts.  Thus certification at the boundary of the
  1362 inference kernel becomes invariant under addition of class relations,
  1363 which is an important monotonicity principle.  Sorts are now minimized
  1364 in the syntax layer only, at the boundary between the end-user and the
  1365 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1366 explicitly in rare situations.
  1367 
  1368 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1369 emphasize that this is in no way a standard operation.
  1370 INCOMPATIBILITY.
  1371 
  1372 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1373 usual for resolution.  Rare INCOMPATIBILITY.
  1374 
  1375 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1376 to emphasize that these only work in a global situation (which is
  1377 quite rare).
  1378 
  1379 * Curried take and drop in library.ML; negative length is interpreted
  1380 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1381 
  1382 * Proof terms: type substitutions on proof constants now use canonical
  1383 order of type variables.  INCOMPATIBILITY for tools working with proof
  1384 terms.
  1385 
  1386 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1387 may no longer carry premises.  User-level specifications are
  1388 transformed accordingly by Thm.add_axiom/add_def.
  1389 
  1390 
  1391 *** System ***
  1392 
  1393 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1394 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1395 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1396 
  1397 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1398 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1399 respectively.
  1400 
  1401 * Old lib/scripts/polyml-platform is superseded by the
  1402 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1403 variant, even on a 64 bit machine.  The following example setting
  1404 prefers 64 bit if available:
  1405 
  1406   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1407 
  1408 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1409 Isabelle/Scala layer for advanced prover interaction and integration.
  1410 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1411 component.
  1412 
  1413 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1414 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1415 similar to the default assignment of the document preparation system
  1416 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1417 provides some operations for direct access to the font without asking
  1418 the user for manual installation.
  1419 
  1420 
  1421 
  1422 New in Isabelle2009-1 (December 2009)
  1423 -------------------------------------
  1424 
  1425 *** General ***
  1426 
  1427 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1428 one backslash should be used, even in ML sources.
  1429 
  1430 
  1431 *** Pure ***
  1432 
  1433 * Locale interpretation propagates mixins along the locale hierarchy.
  1434 The currently only available mixins are the equations used to map
  1435 local definitions to terms of the target domain of an interpretation.
  1436 
  1437 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1438 loc" to print all interpretations of locale "loc" in the theory.
  1439 Interpretations in proofs are not shown.
  1440 
  1441 * Thoroughly revised locales tutorial.  New section on conditional
  1442 interpretation.
  1443 
  1444 * On instantiation of classes, remaining undefined class parameters
  1445 are formally declared.  INCOMPATIBILITY.
  1446 
  1447 
  1448 *** Document preparation ***
  1449 
  1450 * New generalized style concept for printing terms: @{foo (style) ...}
  1451 instead of @{foo_style style ...}  (old form is still retained for
  1452 backward compatibility).  Styles can be also applied for
  1453 antiquotations prop, term_type and typeof.
  1454 
  1455 
  1456 *** HOL ***
  1457 
  1458 * New proof method "smt" for a combination of first-order logic with
  1459 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1460 fixed-size bitvectors; there is also basic support for higher-order
  1461 features (esp. lambda abstractions).  It is an incomplete decision
  1462 procedure based on external SMT solvers using the oracle mechanism;
  1463 for the SMT solver Z3, this method is proof-producing.  Certificates
  1464 are provided to avoid calling the external solvers solely for
  1465 re-checking proofs.  Due to a remote SMT service there is no need for
  1466 installing SMT solvers locally.  See src/HOL/SMT.
  1467 
  1468 * New commands to load and prove verification conditions generated by
  1469 the Boogie program verifier or derived systems (e.g. the Verifying C
  1470 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1471 
  1472 * New counterexample generator tool 'nitpick' based on the Kodkod
  1473 relational model finder.  See src/HOL/Tools/Nitpick and
  1474 src/HOL/Nitpick_Examples.
  1475 
  1476 * New commands 'code_pred' and 'values' to invoke the predicate
  1477 compiler and to enumerate values of inductive predicates.
  1478 
  1479 * A tabled implementation of the reflexive transitive closure.
  1480 
  1481 * New implementation of quickcheck uses generic code generator;
  1482 default generators are provided for all suitable HOL types, records
  1483 and datatypes.  Old quickcheck can be re-activated importing theory
  1484 Library/SML_Quickcheck.
  1485 
  1486 * New testing tool Mirabelle for automated proof tools.  Applies
  1487 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1488 every proof step in a theory.  To be used in batch mode via the
  1489 "mirabelle" utility.
  1490 
  1491 * New proof method "sos" (sum of squares) for nonlinear real
  1492 arithmetic (originally due to John Harison). It requires theory
  1493 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1494 works well in practice on quantifier-free real arithmetic with +, -,
  1495 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1496 inequalities between polynomials.  It makes use of external
  1497 semidefinite programming solvers.  Method "sos" generates a
  1498 certificate that can be pasted into the proof thus avoiding the need
  1499 to call an external tool every time the proof is checked.  See
  1500 src/HOL/Library/Sum_Of_Squares.
  1501 
  1502 * New method "linarith" invokes existing linear arithmetic decision
  1503 procedure only.
  1504 
  1505 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1506 
  1507 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1508 Causes full type information to be output to the ATPs.  This slows
  1509 ATPs down considerably but eliminates a source of unsound "proofs"
  1510 that fail later.
  1511 
  1512 * New method "metisFT": A version of metis that uses full type
  1513 information in order to avoid failures of proof reconstruction.
  1514 
  1515 * New evaluator "approximate" approximates an real valued term using
  1516 the same method as the approximation method.
  1517 
  1518 * Method "approximate" now supports arithmetic expressions as
  1519 boundaries of intervals and implements interval splitting and Taylor
  1520 series expansion.
  1521 
  1522 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1523 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1524 
  1525 * New theory SupInf of the supremum and infimum operators for sets of
  1526 reals.
  1527 
  1528 * New theory Probability, which contains a development of measure
  1529 theory, eventually leading to Lebesgue integration and probability.
  1530 
  1531 * Extended Multivariate Analysis to include derivation and Brouwer's
  1532 fixpoint theorem.
  1533 
  1534 * Reorganization of number theory, INCOMPATIBILITY:
  1535   - new number theory development for nat and int, in theories Divides
  1536     and GCD as well as in new session Number_Theory
  1537   - some constants and facts now suffixed with _nat and _int
  1538     accordingly
  1539   - former session NumberTheory now named Old_Number_Theory, including
  1540     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1541   - moved theory Pocklington from src/HOL/Library to
  1542     src/HOL/Old_Number_Theory
  1543 
  1544 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1545 lcm of finite and infinite sets. It is shown that they form a complete
  1546 lattice.
  1547 
  1548 * Class semiring_div requires superclass no_zero_divisors and proof of
  1549 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1550 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1551 generalized to class semiring_div, subsuming former theorems
  1552 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1553 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1554 INCOMPATIBILITY.
  1555 
  1556 * Refinements to lattice classes and sets:
  1557   - less default intro/elim rules in locale variant, more default
  1558     intro/elim rules in class variant: more uniformity
  1559   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1560     le_inf_iff
  1561   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1562     sup_aci)
  1563   - renamed ACI to inf_sup_aci
  1564   - new class "boolean_algebra"
  1565   - class "complete_lattice" moved to separate theory
  1566     "Complete_Lattice"; corresponding constants (and abbreviations)
  1567     renamed and with authentic syntax:
  1568     Set.Inf ~>    Complete_Lattice.Inf
  1569     Set.Sup ~>    Complete_Lattice.Sup
  1570     Set.INFI ~>   Complete_Lattice.INFI
  1571     Set.SUPR ~>   Complete_Lattice.SUPR
  1572     Set.Inter ~>  Complete_Lattice.Inter
  1573     Set.Union ~>  Complete_Lattice.Union
  1574     Set.INTER ~>  Complete_Lattice.INTER
  1575     Set.UNION ~>  Complete_Lattice.UNION
  1576   - authentic syntax for
  1577     Set.Pow
  1578     Set.image
  1579   - mere abbreviations:
  1580     Set.empty               (for bot)
  1581     Set.UNIV                (for top)
  1582     Set.inter               (for inf, formerly Set.Int)
  1583     Set.union               (for sup, formerly Set.Un)
  1584     Complete_Lattice.Inter  (for Inf)
  1585     Complete_Lattice.Union  (for Sup)
  1586     Complete_Lattice.INTER  (for INFI)
  1587     Complete_Lattice.UNION  (for SUPR)
  1588   - object-logic definitions as far as appropriate
  1589 
  1590 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1591 Un_subset_iff are explicitly deleted as default simp rules; then also
  1592 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1593 deleted to achieve the desired effect.
  1594 
  1595 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1596 rules by default any longer; the same applies to min_max.inf_absorb1
  1597 etc.  INCOMPATIBILITY.
  1598 
  1599 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1600 pred_set_conv by default.  INCOMPATIBILITY.
  1601 
  1602 * Power operations on relations and functions are now one dedicated
  1603 constant "compow" with infix syntax "^^".  Power operation on
  1604 multiplicative monoids retains syntax "^" and is now defined generic
  1605 in class power.  INCOMPATIBILITY.
  1606 
  1607 * Relation composition "R O S" now has a more standard argument order:
  1608 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1609 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1610 break, since the O_assoc rule was not rewritten like this.  Fix using
  1611 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1612 
  1613 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1614 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1615 INCOMPATIBILITY.
  1616 
  1617 * Most rules produced by inductive and datatype package have mandatory
  1618 prefixes.  INCOMPATIBILITY.
  1619 
  1620 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1621 the attribute of the same name.  Each of the theorems in the list
  1622 DERIV_intros assumes composition with an additional function and
  1623 matches a variable to the derivative, which has to be solved by the
  1624 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1625 of most elementary terms.  Former Maclauren.DERIV_tac and
  1626 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1627 INCOMPATIBILITY.
  1628 
  1629 * Code generator attributes follow the usual underscore convention:
  1630     code_unfold     replaces    code unfold
  1631     code_post       replaces    code post
  1632     etc.
  1633   INCOMPATIBILITY.
  1634 
  1635 * Renamed methods:
  1636     sizechange -> size_change
  1637     induct_scheme -> induction_schema
  1638   INCOMPATIBILITY.
  1639 
  1640 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1641 INCOMPATIBILITY, use "undefined" directly.
  1642 
  1643 * Renamed theorems:
  1644     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1645     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1646     Suc_plus1 -> Suc_eq_plus1
  1647     *anti_sym -> *antisym*
  1648     vector_less_eq_def -> vector_le_def
  1649   INCOMPATIBILITY.
  1650 
  1651 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1652 INCOMPATIBILITY.
  1653 
  1654 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1655 INCOMPATIBILITY.
  1656 
  1657 
  1658 *** HOLCF ***
  1659 
  1660 * Theory Representable defines a class "rep" of domains that are
  1661 representable (via an ep-pair) in the universal domain type "udom".
  1662 Instances are provided for all type constructors defined in HOLCF.
  1663 
  1664 * The 'new_domain' command is a purely definitional version of the
  1665 domain package, for representable domains.  Syntax is identical to the
  1666 old domain package.  The 'new_domain' package also supports indirect
  1667 recursion using previously-defined type constructors.  See
  1668 src/HOLCF/ex/New_Domain.thy for examples.
  1669 
  1670 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1671 on the left-hand side of an equation, and then performs
  1672 simplification.  Rewriting is done using rules declared with the
  1673 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1674 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1675 
  1676 * The pattern-match compiler in 'fixrec' can now handle constructors
  1677 with HOL function types.  Pattern-match combinators for the Pair
  1678 constructor are pre-configured.
  1679 
  1680 * The 'fixrec' package now produces better fixed-point induction rules
  1681 for mutually-recursive definitions:  Induction rules have conclusions
  1682 of the form "P foo bar" instead of "P <foo, bar>".
  1683 
  1684 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1685 been renamed to "below".  The name "below" now replaces "less" in many
  1686 theorem names.  (Legacy theorem names using "less" are still supported
  1687 as well.)
  1688 
  1689 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1690 patterns can be used to generate strictness rules, or to make
  1691 functions more strict (much like the bang-patterns supported by the
  1692 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1693 examples.
  1694 
  1695 
  1696 *** ML ***
  1697 
  1698 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1699 errors and run-time exceptions, including detailed source positions.
  1700 
  1701 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1702 identified entries, with some additional information such as source
  1703 position, logical grouping etc.
  1704 
  1705 * Theory and context data is now introduced by the simplified and
  1706 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1707 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1708 copy operation) is still available for some time.
  1709 
  1710 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1711 provides a high-level programming interface to synchronized state
  1712 variables with atomic update.  This works via pure function
  1713 application within a critical section -- its runtime should be as
  1714 short as possible; beware of deadlocks if critical code is nested,
  1715 either directly or indirectly via other synchronized variables!
  1716 
  1717 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1718 wraps raw ML references, explicitly indicating their non-thread-safe
  1719 behaviour.  The Isar toplevel keeps this structure open, to
  1720 accommodate Proof General as well as quick and dirty interactive
  1721 experiments with references.
  1722 
  1723 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1724 parallel tactical reasoning.
  1725 
  1726 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1727 are similar to SUBPROOF, but are slightly more flexible: only the
  1728 specified parts of the subgoal are imported into the context, and the
  1729 body tactic may introduce new subgoals and schematic variables.
  1730 
  1731 * Old tactical METAHYPS, which does not observe the proof context, has
  1732 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1733 or Subgoal.FOCUS etc.
  1734 
  1735 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1736 functors have their own ML name space there is no point to mark them
  1737 separately.)  Minor INCOMPATIBILITY.
  1738 
  1739 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1740 
  1741 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1742 INCOMPATIBILITY.
  1743 
  1744 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1745 mode, which avoids critical setmp.
  1746 
  1747 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1748 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1749 Attrib/Method.setup introduced in Isabelle2009.
  1750 
  1751 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1752 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1753 last resort.  INCOMPATIBILITY.
  1754 
  1755 * Display.pretty_thm now requires a proper context (cf. former
  1756 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1757 or even Display.pretty_thm_without_context as last resort.
  1758 INCOMPATIBILITY.
  1759 
  1760 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1761 Syntax.pretty_typ/term directly, preferably with proper context
  1762 instead of global theory.
  1763 
  1764 
  1765 *** System ***
  1766 
  1767 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1768 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1769 usedir option -q.
  1770 
  1771 * Support for additional "Isabelle components" via etc/components, see
  1772 also the system manual.
  1773 
  1774 * The isabelle makeall tool now operates on all components with
  1775 IsaMakefile, not just hardwired "logics".
  1776 
  1777 * Removed "compress" option from isabelle-process and isabelle usedir;
  1778 this is always enabled.
  1779 
  1780 * Discontinued support for Poly/ML 4.x versions.
  1781 
  1782 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  1783 on a given logic image.  This requires the lighttpd webserver and is
  1784 currently supported on Linux only.
  1785 
  1786 
  1787 
  1788 New in Isabelle2009 (April 2009)
  1789 --------------------------------
  1790 
  1791 *** General ***
  1792 
  1793 * Simplified main Isabelle executables, with less surprises on
  1794 case-insensitive file-systems (such as Mac OS).
  1795 
  1796   - The main Isabelle tool wrapper is now called "isabelle" instead of
  1797     "isatool."
  1798 
  1799   - The former "isabelle" alias for "isabelle-process" has been
  1800     removed (should rarely occur to regular users).
  1801 
  1802   - The former "isabelle-interface" and its alias "Isabelle" have been
  1803     removed (interfaces are now regular Isabelle tools).
  1804 
  1805 Within scripts and make files, the Isabelle environment variables
  1806 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  1807 respectively.  (The latter are still available as legacy feature.)
  1808 
  1809 The old isabelle-interface wrapper could react in confusing ways if
  1810 the interface was uninstalled or changed otherwise.  Individual
  1811 interface tool configuration is now more explicit, see also the
  1812 Isabelle system manual.  In particular, Proof General is now available
  1813 via "isabelle emacs".
  1814 
  1815 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  1816 purge installed copies of Isabelle executables and re-run "isabelle
  1817 install -p ...", or use symlinks.
  1818 
  1819 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  1820 old ~/isabelle, which was slightly non-standard and apt to cause
  1821 surprises on case-insensitive file-systems (such as Mac OS).
  1822 
  1823 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  1824 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  1825 care is required when using older releases of Isabelle.  Note that
  1826 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  1827 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  1828 
  1829 * Proofs of fully specified statements are run in parallel on
  1830 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  1831 a regular 4-core machine, if the initial heap space is made reasonably
  1832 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  1833 
  1834 * The main reference manuals ("isar-ref", "implementation", and
  1835 "system") have been updated and extended.  Formally checked references
  1836 as hyperlinks are now available uniformly.
  1837 
  1838 
  1839 *** Pure ***
  1840 
  1841 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  1842 respects.  The most important changes are listed below.  See the
  1843 Tutorial on Locales ("locales" manual) for details.
  1844 
  1845 - In locale expressions, instantiation replaces renaming.  Parameters
  1846 must be declared in a for clause.  To aid compatibility with previous
  1847 parameter inheritance, in locale declarations, parameters that are not
  1848 'touched' (instantiation position "_" or omitted) are implicitly added
  1849 with their syntax at the beginning of the for clause.
  1850 
  1851 - Syntax from abbreviations and definitions in locales is available in
  1852 locale expressions and context elements.  The latter is particularly
  1853 useful in locale declarations.
  1854 
  1855 - More flexible mechanisms to qualify names generated by locale
  1856 expressions.  Qualifiers (prefixes) may be specified in locale
  1857 expressions, and can be marked as mandatory (syntax: "name!:") or
  1858 optional (syntax "name?:").  The default depends for plain "name:"
  1859 depends on the situation where a locale expression is used: in
  1860 commands 'locale' and 'sublocale' prefixes are optional, in
  1861 'interpretation' and 'interpret' prefixes are mandatory.  The old
  1862 implicit qualifiers derived from the parameter names of a locale are
  1863 no longer generated.
  1864 
  1865 - Command "sublocale l < e" replaces "interpretation l < e".  The
  1866 instantiation clause in "interpretation" and "interpret" (square
  1867 brackets) is no longer available.  Use locale expressions.
  1868 
  1869 - When converting proof scripts, mandatory qualifiers in
  1870 'interpretation' and 'interpret' should be retained by default, even
  1871 if this is an INCOMPATIBILITY compared to former behavior.  In the
  1872 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  1873 in locale expressions range over a single locale instance only.
  1874 
  1875 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  1876 In existing theorem specifications replace the includes element by the
  1877 respective context elements of the included locale, omitting those
  1878 that are already present in the theorem specification.  Multiple
  1879 assume elements of a locale should be replaced by a single one
  1880 involving the locale predicate.  In the proof body, declarations (most
  1881 notably theorems) may be regained by interpreting the respective
  1882 locales in the proof context as required (command "interpret").
  1883 
  1884 If using "includes" in replacement of a target solely because the
  1885 parameter types in the theorem are not as general as in the target,
  1886 consider declaring a new locale with additional type constraints on
  1887 the parameters (context element "constrains").
  1888 
  1889 - Discontinued "locale (open)".  INCOMPATIBILITY.
  1890 
  1891 - Locale interpretation commands no longer attempt to simplify goal.
  1892 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  1893 methods intro_locales and unfold_locales to clarify.
  1894 
  1895 - Locale interpretation commands no longer accept interpretation
  1896 attributes.  INCOMPATIBILITY.
  1897 
  1898 * Class declaration: so-called "base sort" must not be given in import
  1899 list any longer, but is inferred from the specification.  Particularly
  1900 in HOL, write
  1901 
  1902     class foo = ...
  1903 
  1904 instead of
  1905 
  1906     class foo = type + ...
  1907 
  1908 * Class target: global versions of theorems stemming do not carry a
  1909 parameter prefix any longer.  INCOMPATIBILITY.
  1910 
  1911 * Class 'instance' command no longer accepts attached definitions.
  1912 INCOMPATIBILITY, use proper 'instantiation' target instead.
  1913 
  1914 * Recovered hiding of consts, which was accidentally broken in
  1915 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  1916 makes c inaccessible; consider using ``hide (open) const c'' instead.
  1917 
  1918 * Slightly more coherent Pure syntax, with updated documentation in
  1919 isar-ref manual.  Removed locales meta_term_syntax and
  1920 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  1921 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  1922 directly in regular applications.
  1923 
  1924 * There is a new syntactic category "float_const" for signed decimal
  1925 fractions (e.g. 123.45 or -123.45).
  1926 
  1927 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  1928 interface with 'setup' command instead.
  1929 
  1930 * Command 'local_setup' is similar to 'setup', but operates on a local
  1931 theory context.
  1932 
  1933 * The 'axiomatization' command now only works within a global theory
  1934 context.  INCOMPATIBILITY.
  1935 
  1936 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  1937 hypotheses.  Sorts required in the course of reasoning need to be
  1938 covered by the constraints in the initial statement, completed by the
  1939 type instance information of the background theory.  Non-trivial sort
  1940 hypotheses, which rarely occur in practice, may be specified via
  1941 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  1942 
  1943   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  1944 
  1945 The result contains an implicit sort hypotheses as before --
  1946 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  1947 normalization.
  1948 
  1949 * Generalized Isar history, with support for linear undo, direct state
  1950 addressing etc.
  1951 
  1952 * Changed defaults for unify configuration options:
  1953 
  1954   unify_trace_bound = 50 (formerly 25)
  1955   unify_search_bound = 60 (formerly 30)
  1956 
  1957 * Different bookkeeping for code equations (INCOMPATIBILITY):
  1958 
  1959   a) On theory merge, the last set of code equations for a particular
  1960      constant is taken (in accordance with the policy applied by other
  1961      parts of the code generator framework).
  1962 
  1963   b) Code equations stemming from explicit declarations (e.g. code
  1964      attribute) gain priority over default code equations stemming
  1965      from definition, primrec, fun etc.
  1966 
  1967 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  1968 
  1969 * Unified theorem tables for both code generators.  Thus [code
  1970 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  1971 
  1972 * Command 'find_consts' searches for constants based on type and name
  1973 patterns, e.g.
  1974 
  1975     find_consts "_ => bool"
  1976 
  1977 By default, matching is against subtypes, but it may be restricted to
  1978 the whole type.  Searching by name is possible.  Multiple queries are
  1979 conjunctive and queries may be negated by prefixing them with a
  1980 hyphen:
  1981 
  1982     find_consts strict: "_ => bool" name: "Int" -"int => int"
  1983 
  1984 * New 'find_theorems' criterion "solves" matches theorems that
  1985 directly solve the current goal (modulo higher-order unification).
  1986 
  1987 * Auto solve feature for main theorem statements: whenever a new goal
  1988 is stated, "find_theorems solves" is called; any theorems that could
  1989 solve the lemma directly are listed as part of the goal state.
  1990 Cf. associated options in Proof General Isabelle settings menu,
  1991 enabled by default, with reasonable timeout for pathological cases of
  1992 higher-order unification.
  1993 
  1994 
  1995 *** Document preparation ***
  1996 
  1997 * Antiquotation @{lemma} now imitates a regular terminal proof,
  1998 demanding keyword 'by' and supporting the full method expression
  1999 syntax just like the Isar command 'by'.
  2000 
  2001 
  2002 *** HOL ***
  2003 
  2004 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2005 points Main and Complex_Main remain as before.
  2006 
  2007 * Logic image HOL-Plain provides a minimal HOL with the most important
  2008 tools available (inductive, datatype, primrec, ...).  This facilitates
  2009 experimentation and tool development.  Note that user applications
  2010 (and library theories) should never refer to anything below theory
  2011 Main, as before.
  2012 
  2013 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2014 experimentation due to shorter build times.
  2015 
  2016 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2017 were previously part of former HOL-Complex.  Entry point Hyperreal
  2018 remains valid, but theories formerly using Complex_Main should now use
  2019 new entry point Hypercomplex.
  2020 
  2021 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2022 Posix processes.  Avoids potentially expensive forking of the ML
  2023 process.  New thread-based implementation also works on non-Unix
  2024 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2025 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2026 commands are covered in the isar-ref manual.
  2027 
  2028 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2029 sledgehammer without local ATP installation (Vampire etc.). Other
  2030 provers may be included via suitable ML wrappers, see also
  2031 src/HOL/ATP_Linkup.thy.
  2032 
  2033 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2034 menu.
  2035 
  2036 * The metis method no longer fails because the theorem is too trivial
  2037 (contains the empty clause).
  2038 
  2039 * The metis method now fails in the usual manner, rather than raising
  2040 an exception, if it determines that it cannot prove the theorem.
  2041 
  2042 * Method "coherent" implements a prover for coherent logic (see also
  2043 src/Tools/coherent.ML).
  2044 
  2045 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2046 "undefined" is the right choice to replace "arbitrary", though
  2047 logically there is no difference.  INCOMPATIBILITY.
  2048 
  2049 * Command "value" now integrates different evaluation mechanisms.  The
  2050 result of the first successful evaluation mechanism is printed.  In
  2051 square brackets a particular named evaluation mechanisms may be
  2052 specified (currently, [SML], [code] or [nbe]).  See further
  2053 src/HOL/ex/Eval_Examples.thy.
  2054 
  2055 * Normalization by evaluation now allows non-leftlinear equations.
  2056 Declare with attribute [code nbe].
  2057 
  2058 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2059 as the structured Isar versions "cases" and "induct", cf. the
  2060 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2061 are now presented as a list of individual projections
  2062 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2063 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2064 rare situations a different rule is selected --- notably nested tuple
  2065 elimination instead of former prod.exhaust: use explicit (case_tac t
  2066 rule: prod.exhaust) here.
  2067 
  2068 * Attributes "cases", "induct", "coinduct" support "del" option.
  2069 
  2070 * Removed fact "case_split_thm", which duplicates "case_split".
  2071 
  2072 * The option datatype has been moved to a new theory Option.  Renamed
  2073 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2074 
  2075 * New predicate "strict_mono" classifies strict functions on partial
  2076 orders.  With strict functions on linear orders, reasoning about
  2077 (in)equalities is facilitated by theorems "strict_mono_eq",
  2078 "strict_mono_less_eq" and "strict_mono_less".
  2079 
  2080 * Some set operations are now proper qualified constants with
  2081 authentic syntax.  INCOMPATIBILITY:
  2082 
  2083     op Int ~>   Set.Int
  2084     op Un ~>    Set.Un
  2085     INTER ~>    Set.INTER
  2086     UNION ~>    Set.UNION
  2087     Inter ~>    Set.Inter
  2088     Union ~>    Set.Union
  2089     {} ~>       Set.empty
  2090     UNIV ~>     Set.UNIV
  2091 
  2092 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2093 theory Set.
  2094 
  2095 * Auxiliary class "itself" has disappeared -- classes without any
  2096 parameter are treated as expected by the 'class' command.
  2097 
  2098 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2099 
  2100 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2101 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2102 
  2103 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2104 method "approximation".  It proves formulas on real values by using
  2105 interval arithmetic.  In the formulas are also the transcendental
  2106 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2107 allowed. For examples see
  2108 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2109 
  2110 * Theory "Reflection" now resides in HOL/Library.
  2111 
  2112 * Entry point to Word library now simply named "Word".
  2113 INCOMPATIBILITY.
  2114 
  2115 * Made source layout more coherent with logical distribution
  2116 structure:
  2117 
  2118     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2119     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2120     src/HOL/Library/GCD.thy ~> src/HOL/
  2121     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2122     src/HOL/Library/Parity.thy ~> src/HOL/
  2123     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2124     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2125     src/HOL/Real/Lubs.thy ~> src/HOL/
  2126     src/HOL/Real/PReal.thy ~> src/HOL/
  2127     src/HOL/Real/Rational.thy ~> src/HOL/
  2128     src/HOL/Real/RComplete.thy ~> src/HOL/
  2129     src/HOL/Real/RealDef.thy ~> src/HOL/
  2130     src/HOL/Real/RealPow.thy ~> src/HOL/
  2131     src/HOL/Real/Real.thy ~> src/HOL/
  2132     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2133     src/HOL/Complex/Complex.thy ~> src/HOL/
  2134     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2135     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2136     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2137     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2138     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2139     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2140     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2141     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2142     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2143     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2144     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2145     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2146     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2147     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2148     src/HOL/Real/Float ~> src/HOL/Library/
  2149     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2150     src/HOL/Real/RealVector.thy ~> src/HOL/
  2151 
  2152     src/HOL/arith_data.ML ~> src/HOL/Tools
  2153     src/HOL/hologic.ML ~> src/HOL/Tools
  2154     src/HOL/simpdata.ML ~> src/HOL/Tools
  2155     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2156     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2157     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2158     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2159     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2160     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2161     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2162 
  2163     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2164     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2165     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2166     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2167     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2168     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2169 
  2170 * If methods "eval" and "evaluation" encounter a structured proof
  2171 state with !!/==>, only the conclusion is evaluated to True (if
  2172 possible), avoiding strange error messages.
  2173 
  2174 * Method "sizechange" automates termination proofs using (a
  2175 modification of) the size-change principle.  Requires SAT solver.  See
  2176 src/HOL/ex/Termination.thy for examples.
  2177 
  2178 * Simplifier: simproc for let expressions now unfolds if bound
  2179 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2180 
  2181 * Method "arith": Linear arithmetic now ignores all inequalities when
  2182 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2183 
  2184 * New attribute "arith" for facts that should always be used
  2185 automatically by arithmetic. It is intended to be used locally in
  2186 proofs, e.g.
  2187 
  2188   assumes [arith]: "x > 0"
  2189 
  2190 Global usage is discouraged because of possible performance impact.
  2191 
  2192 * New classes "top" and "bot" with corresponding operations "top" and
  2193 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2194 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2195 
  2196 * Changed definition lemma "less_fun_def" in order to provide an
  2197 instance for preorders on functions; use lemma "less_le" instead.
  2198 INCOMPATIBILITY.
  2199 
  2200 * Theory Orderings: class "wellorder" moved here, with explicit
  2201 induction rule "less_induct" as assumption.  For instantiation of
  2202 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2203 INCOMPATIBILITY.
  2204 
  2205 * Theory Orderings: added class "preorder" as superclass of "order".
  2206 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2207 etc. slightly changed.  Some theorems named order_class.* now named
  2208 preorder_class.*.
  2209 
  2210 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2211 "diag" to "Id_on".
  2212 
  2213 * Theory Finite_Set: added a new fold combinator of type
  2214 
  2215   ('a => 'b => 'b) => 'b => 'a set => 'b
  2216 
  2217 Occasionally this is more convenient than the old fold combinator
  2218 which is now defined in terms of the new one and renamed to
  2219 fold_image.
  2220 
  2221 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2222 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2223 extended with further lemmas!).  At the moment both still exist but
  2224 the former will disappear at some point.
  2225 
  2226 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2227 class recpower.  Type-specific simp rules for various recpower types
  2228 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2229 
  2230 rat_power_0    -> power_0
  2231 rat_power_Suc  -> power_Suc
  2232 realpow_0      -> power_0
  2233 realpow_Suc    -> power_Suc
  2234 complexpow_0   -> power_0
  2235 complexpow_Suc -> power_Suc
  2236 power_poly_0   -> power_0
  2237 power_poly_Suc -> power_Suc
  2238 
  2239 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2240 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2241 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2242 of lemmas from Divides has been generalized from nat to class
  2243 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2244 renames resulting from duplicate elimination:
  2245 
  2246     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2247     zero_dvd_iff ~>         dvd_0_left_iff
  2248     dvd_0 ~>                dvd_0_right
  2249     DIVISION_BY_ZERO_DIV ~> div_by_0
  2250     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2251     mult_div ~>             div_mult_self2_is_id
  2252     mult_mod ~>             mod_mult_self2_is_0
  2253 
  2254 * Theory IntDiv: removed many lemmas that are instances of class-based
  2255 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2256 rename old lemmas as follows:
  2257 
  2258 dvd_diff               -> nat_dvd_diff
  2259 dvd_zminus_iff         -> dvd_minus_iff
  2260 mod_add1_eq            -> mod_add_eq
  2261 mod_mult1_eq           -> mod_mult_right_eq
  2262 mod_mult1_eq'          -> mod_mult_left_eq
  2263 mod_mult_distrib_mod   -> mod_mult_eq
  2264 nat_mod_add_left_eq    -> mod_add_left_eq
  2265 nat_mod_add_right_eq   -> mod_add_right_eq
  2266 nat_mod_div_trivial    -> mod_div_trivial
  2267 nat_mod_mod_trivial    -> mod_mod_trivial
  2268 zdiv_zadd_self1        -> div_add_self1
  2269 zdiv_zadd_self2        -> div_add_self2
  2270 zdiv_zmult_self1       -> div_mult_self2_is_id
  2271 zdiv_zmult_self2       -> div_mult_self1_is_id
  2272 zdvd_triv_left         -> dvd_triv_left
  2273 zdvd_triv_right        -> dvd_triv_right
  2274 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2275 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2276 zmod_zadd_left_eq      -> mod_add_left_eq
  2277 zmod_zadd_right_eq     -> mod_add_right_eq
  2278 zmod_zadd_self1        -> mod_add_self1
  2279 zmod_zadd_self2        -> mod_add_self2
  2280 zmod_zadd1_eq          -> mod_add_eq
  2281 zmod_zdiff1_eq         -> mod_diff_eq
  2282 zmod_zdvd_zmod         -> mod_mod_cancel
  2283 zmod_zmod_cancel       -> mod_mod_cancel
  2284 zmod_zmult_self1       -> mod_mult_self2_is_0
  2285 zmod_zmult_self2       -> mod_mult_self1_is_0
  2286 zmod_1                 -> mod_by_1
  2287 zdiv_1                 -> div_by_1
  2288 zdvd_abs1              -> abs_dvd_iff
  2289 zdvd_abs2              -> dvd_abs_iff
  2290 zdvd_refl              -> dvd_refl
  2291 zdvd_trans             -> dvd_trans
  2292 zdvd_zadd              -> dvd_add
  2293 zdvd_zdiff             -> dvd_diff
  2294 zdvd_zminus_iff        -> dvd_minus_iff
  2295 zdvd_zminus2_iff       -> minus_dvd_iff
  2296 zdvd_zmultD            -> dvd_mult_right
  2297 zdvd_zmultD2           -> dvd_mult_left
  2298 zdvd_zmult_mono        -> mult_dvd_mono
  2299 zdvd_0_right           -> dvd_0_right
  2300 zdvd_0_left            -> dvd_0_left_iff
  2301 zdvd_1_left            -> one_dvd
  2302 zminus_dvd_iff         -> minus_dvd_iff
  2303 
  2304 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2305 
  2306 * The real numbers offer decimal input syntax: 12.34 is translated
  2307 into 1234/10^2. This translation is not reversed upon output.
  2308 
  2309 * Theory Library/Polynomial defines an abstract type 'a poly of
  2310 univariate polynomials with coefficients of type 'a.  In addition to
  2311 the standard ring operations, it also supports div and mod.  Code
  2312 generation is also supported, using list-style constructors.
  2313 
  2314 * Theory Library/Inner_Product defines a class of real_inner for real
  2315 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2316 => real.  Class real_inner is a subclass of real_normed_vector from
  2317 theory RealVector.
  2318 
  2319 * Theory Library/Product_Vector provides instances for the product
  2320 type 'a * 'b of several classes from RealVector and Inner_Product.
  2321 Definitions of addition, subtraction, scalar multiplication, norms,
  2322 and inner products are included.
  2323 
  2324 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2325 addition to the field operations, numerals and case syntax are also
  2326 supported.
  2327 
  2328 * Theory Library/Diagonalize provides constructive version of Cantor's
  2329 first diagonalization argument.
  2330 
  2331 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2332 zlcm (for int); carried together from various gcd/lcm developements in
  2333 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2334 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2335 may recover tupled syntax as follows:
  2336 
  2337     hide (open) const gcd
  2338     abbreviation gcd where
  2339       "gcd == (%(a, b). GCD.gcd a b)"
  2340     notation (output)
  2341       GCD.gcd ("gcd '(_, _')")
  2342 
  2343 The same works for lcm, zgcd, zlcm.
  2344 
  2345 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2346 instantiations for algebraic structures.  Removed some duplicate
  2347 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2348 
  2349 * ML antiquotation @{code} takes a constant as argument and generates
  2350 corresponding code in background and inserts name of the corresponding
  2351 resulting ML value/function/datatype constructor binding in place.
  2352 All occurrences of @{code} with a single ML block are generated
  2353 simultaneously.  Provides a generic and safe interface for
  2354 instrumentalizing code generation.  See
  2355 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2356 In future you ought to refrain from ad-hoc compiling generated SML
  2357 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2358 cannot refer to constants for which user-defined serializations are
  2359 set.  Refer to the corresponding ML counterpart directly in that
  2360 cases.
  2361 
  2362 * Command 'rep_datatype': instead of theorem names the command now
  2363 takes a list of terms denoting the constructors of the type to be
  2364 represented as datatype.  The characteristic theorems have to be
  2365 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2366 have disappeared in favour of existing ones:
  2367 
  2368     unit_induct                 ~> unit.induct
  2369     prod_induct                 ~> prod.induct
  2370     sum_induct                  ~> sum.induct
  2371     Suc_Suc_eq                  ~> nat.inject
  2372     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2373 
  2374 
  2375 *** HOL-Algebra ***
  2376 
  2377 * New locales for orders and lattices where the equivalence relation
  2378 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2379 locales use a record structure with field eq for the equivalence.
  2380 
  2381 * New theory of factorial domains.
  2382 
  2383 * Units_l_inv and Units_r_inv are now simp rules by default.
  2384 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2385 and/or r_inv will now also require deletion of these lemmas.
  2386 
  2387 * Renamed the following theorems, INCOMPATIBILITY:
  2388 
  2389 UpperD ~> Upper_memD
  2390 LowerD ~> Lower_memD
  2391 least_carrier ~> least_closed
  2392 greatest_carrier ~> greatest_closed
  2393 greatest_Lower_above ~> greatest_Lower_below
  2394 one_zero ~> carrier_one_zero
  2395 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2396 
  2397 
  2398 *** HOL-Nominal ***
  2399 
  2400 * Nominal datatypes can now contain type-variables.
  2401 
  2402 * Commands 'nominal_inductive' and 'equivariance' work with local
  2403 theory targets.
  2404 
  2405 * Nominal primrec can now works with local theory targets and its
  2406 specification syntax now conforms to the general format as seen in
  2407 'inductive' etc.
  2408 
  2409 * Method "perm_simp" honours the standard simplifier attributes
  2410 (no_asm), (no_asm_use) etc.
  2411 
  2412 * The new predicate #* is defined like freshness, except that on the
  2413 left hand side can be a set or list of atoms.
  2414 
  2415 * Experimental command 'nominal_inductive2' derives strong induction
  2416 principles for inductive definitions.  In contrast to
  2417 'nominal_inductive', which can only deal with a fixed number of
  2418 binders, it can deal with arbitrary expressions standing for sets of
  2419 atoms to be avoided.  The only inductive definition we have at the
  2420 moment that needs this generalisation is the typing rule for Lets in
  2421 the algorithm W:
  2422 
  2423  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2424  -----------------------------------------------------------------
  2425          Gamma |- Let x be t1 in t2 : T2
  2426 
  2427 In this rule one wants to avoid all the binders that are introduced by
  2428 "close Gamma T1".  We are looking for other examples where this
  2429 feature might be useful.  Please let us know.
  2430 
  2431 
  2432 *** HOLCF ***
  2433 
  2434 * Reimplemented the simplification procedure for proving continuity
  2435 subgoals.  The new simproc is extensible; users can declare additional
  2436 continuity introduction rules with the attribute [cont2cont].
  2437 
  2438 * The continuity simproc now uses a different introduction rule for
  2439 solving continuity subgoals on terms with lambda abstractions.  In
  2440 some rare cases the new simproc may fail to solve subgoals that the
  2441 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2442 Potential INCOMPATIBILITY.
  2443 
  2444 * Command 'fixrec': specification syntax now conforms to the general
  2445 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2446 examples.  INCOMPATIBILITY.
  2447 
  2448 
  2449 *** ZF ***
  2450 
  2451 * Proof of Zorn's Lemma for partial orders.
  2452 
  2453 
  2454 *** ML ***
  2455 
  2456 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2457 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2458 depends on multithreading, so timouts will not work before Poly/ML
  2459 5.2.1!
  2460 
  2461 * High-level support for concurrent ML programming, see
  2462 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2463 particularly convenient to organize independent functional
  2464 computations.  The concept of "synchronized variables" provides a
  2465 higher-order interface for components with shared state, avoiding the
  2466 delicate details of mutexes and condition variables.  (Requires
  2467 Poly/ML 5.2.1 or later.)
  2468 
  2469 * ML bindings produced via Isar commands are stored within the Isar
  2470 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2471 become thread-safe and work with undo as expected (concerning
  2472 top-level bindings, not side-effects on global references).
  2473 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2474 compiler at runtime; really global bindings need to be given outside a
  2475 theory.  (Requires Poly/ML 5.2 or later.)
  2476 
  2477 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2478 context.  Top-level ML bindings are stored within the proof context in
  2479 a purely sequential fashion, disregarding the nested proof structure.
  2480 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2481 proof.  (Requires Poly/ML 5.2 or later.)
  2482 
  2483 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2484 and Method.setup, as well as Isar commands 'attribute_setup' and
  2485 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2486 existing code accordingly, or use plain 'setup' together with old
  2487 Method.add_method.
  2488 
  2489 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2490 to 'a -> thm, while results are always tagged with an authentic oracle
  2491 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2492 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2493 accordingly.  Note that extra performance may be gained by producing
  2494 the cterm carefully, avoiding slow Thm.cterm_of.
  2495 
  2496 * Simplified interface for defining document antiquotations via
  2497 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2498 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2499 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2500 examples.
  2501 
  2502 * More systematic treatment of long names, abstract name bindings, and
  2503 name space operations.  Basic operations on qualified names have been
  2504 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2505 Long_Name.append.  Old type bstring has been mostly replaced by
  2506 abstract type binding (see structure Binding), which supports precise
  2507 qualification by packages and local theory targets, as well as proper
  2508 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2509 bstring values into Binding.name, or better pass through abstract
  2510 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2511 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2512 
  2513 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2514 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2515 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2516 
  2517 * Disposed old type and term read functions (Sign.read_def_typ,
  2518 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2519 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2520 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2521 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2522 resort for legacy applications.
  2523 
  2524 * Disposed old declarations, tactics, tactic combinators that refer to
  2525 the simpset or claset of an implicit theory (such as Addsimps,
  2526 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2527 embedded ML text, or local_simpset_of with a proper context passed as
  2528 explicit runtime argument.
  2529 
  2530 * Rules and tactics that read instantiations (read_instantiate,
  2531 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2532 context, which is required for parsing and type-checking.  Moreover,
  2533 the variables are specified as plain indexnames, not string encodings
  2534 thereof.  INCOMPATIBILITY.
  2535 
  2536 * Generic Toplevel.add_hook interface allows to analyze the result of
  2537 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2538 for theorem dependency output of transactions resulting in a new
  2539 theory state.
  2540 
  2541 * ML antiquotations: block-structured compilation context indicated by
  2542 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2543 
  2544   @{binding name}                         - basic name binding
  2545   @{let ?pat = term}                      - term abbreviation (HO matching)
  2546   @{note name = fact}                     - fact abbreviation
  2547   @{thm fact}                             - singleton fact (with attributes)
  2548   @{thms fact}                            - general fact (with attributes)
  2549   @{lemma prop by method}                 - singleton goal
  2550   @{lemma prop by meth1 meth2}            - singleton goal
  2551   @{lemma prop1 ... propN by method}      - general goal
  2552   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2553   @{lemma (open) ...}                     - open derivation
  2554 
  2555 
  2556 *** System ***
  2557 
  2558 * The Isabelle "emacs" tool provides a specific interface to invoke
  2559 Proof General / Emacs, with more explicit failure if that is not
  2560 installed (the old isabelle-interface script silently falls back on
  2561 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2562 installation location of the Proof General distribution.
  2563 
  2564 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2565 the Isabelle process into a JVM/Scala application.  See
  2566 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2567 process wrapper has been discontinued.)
  2568 
  2569 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2570 
  2571 * Various status messages (with exact source position information) are
  2572 emitted, if proper markup print mode is enabled.  This allows
  2573 user-interface components to provide detailed feedback on internal
  2574 prover operations.
  2575 
  2576 
  2577 
  2578 New in Isabelle2008 (June 2008)
  2579 -------------------------------
  2580 
  2581 *** General ***
  2582 
  2583 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2584 and updated, with formally checked references as hyperlinks.
  2585 
  2586 * Theory loader: use_thy (and similar operations) no longer set the
  2587 implicit ML context, which was occasionally hard to predict and in
  2588 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2589 provides a proper context already.
  2590 
  2591 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2592 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2593 'use' within a theory file will do the job.
  2594 
  2595 * Name space merge now observes canonical order, i.e. the second space
  2596 is inserted into the first one, while existing entries in the first
  2597 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2598 swap theory imports.
  2599 
  2600 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2601 INCOMPATIBILITY in identifier syntax etc.
  2602 
  2603 * Outer syntax: string tokens no longer admit escaped white space,
  2604 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2605 white space without escapes.
  2606 
  2607 * Outer syntax: string tokens may contain arbitrary character codes
  2608 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2609 "foo_bar".
  2610 
  2611 
  2612 *** Pure ***
  2613 
  2614 * Context-dependent token translations.  Default setup reverts locally
  2615 fixed variables, and adds hilite markup for undeclared frees.
  2616 
  2617 * Unused theorems can be found using the new command 'unused_thms'.
  2618 There are three ways of invoking it:
  2619 
  2620 (1) unused_thms
  2621      Only finds unused theorems in the current theory.
  2622 
  2623 (2) unused_thms thy_1 ... thy_n -
  2624      Finds unused theorems in the current theory and all of its ancestors,
  2625      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2626 
  2627 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2628      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2629      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2630      their ancestors.
  2631 
  2632 In order to increase the readability of the list produced by
  2633 unused_thms, theorems that have been created by a particular instance
  2634 of a theory command such as 'inductive' or 'function' are considered
  2635 to belong to the same "group", meaning that if at least one theorem in
  2636 this group is used, the other theorems in the same group are no longer
  2637 reported as unused.  Moreover, if all theorems in the group are
  2638 unused, only one theorem in the group is displayed.
  2639 
  2640 Note that proof objects have to be switched on in order for
  2641 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2642 usually the case when using Proof General with the default settings).
  2643 
  2644 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2645 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2646 duplicate fact bindings, or even accidental fact duplications.  Note
  2647 that tools may maintain dynamically scoped facts systematically, using
  2648 PureThy.add_thms_dynamic.
  2649 
  2650 * Command 'hide' now allows to hide from "fact" name space as well.
  2651 
  2652 * Eliminated destructive theorem database, simpset, claset, and
  2653 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2654 update of theories within ML code.
  2655 
  2656 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2657 INCOMPATIBILITY, object-logics depending on former Pure require
  2658 additional setup PureThy.old_appl_syntax_setup; object-logics
  2659 depending on former CPure need to refer to Pure.
  2660 
  2661 * Commands 'use' and 'ML' are now purely functional, operating on
  2662 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2663 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2664 INCOMPATIBILITY.
  2665 
  2666 * Command 'setup': discontinued implicit version with ML reference.
  2667 
  2668 * Instantiation target allows for simultaneous specification of class
  2669 instance operations together with an instantiation proof.
  2670 Type-checking phase allows to refer to class operations uniformly.
  2671 See src/HOL/Complex/Complex.thy for an Isar example and
  2672 src/HOL/Library/Eval.thy for an ML example.
  2673 
  2674 * Indexing of literal facts: be more serious about including only
  2675 facts from the visible specification/proof context, but not the
  2676 background context (locale etc.).  Affects `prop` notation and method
  2677 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2678 situations.
  2679 
  2680 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2681 "(open)" option, which used to expose internal bound variables to the
  2682 proof text.
  2683 
  2684 * Isar statements: removed obsolete case "rule_context".
  2685 INCOMPATIBILITY, better use explicit fixes/assumes.
  2686 
  2687 * Locale proofs: default proof step now includes 'unfold_locales';
  2688 hence 'proof' without argument may be used to unfold locale
  2689 predicates.
  2690 
  2691 
  2692 *** Document preparation ***
  2693 
  2694 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2695 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2696 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2697 spot); renamed link color from "darkblue" to "linkcolor" (default
  2698 value unchanged, can be redefined via \definecolor); no longer sets
  2699 "a4paper" option (unnecessary or even intrusive).
  2700 
  2701 * Antiquotation @{lemma A method} proves proposition A by the given
  2702 method (either a method name or a method name plus (optional) method
  2703 arguments in parentheses) and prints A just like @{prop A}.
  2704 
  2705 
  2706 *** HOL ***
  2707 
  2708 * New primrec package.  Specification syntax conforms in style to
  2709 definition/function/....  No separate induction rule is provided.  The
  2710 "primrec" command distinguishes old-style and new-style specifications
  2711 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2712 When adjusting theories, beware: constants stemming from new-style
  2713 primrec specifications have authentic syntax.
  2714 
  2715 * Metis prover is now an order of magnitude faster, and also works
  2716 with multithreading.
  2717 
  2718 * Metis: the maximum number of clauses that can be produced from a
  2719 theorem is now given by the attribute max_clauses.  Theorems that
  2720 exceed this number are ignored, with a warning printed.
  2721 
  2722 * Sledgehammer no longer produces structured proofs by default. To
  2723 enable, declare [[sledgehammer_full = true]].  Attributes
  2724 reconstruction_modulus, reconstruction_sorts renamed
  2725 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2726 
  2727 * Method "induct_scheme" derives user-specified induction rules
  2728 from well-founded induction and completeness of patterns. This factors
  2729 out some operations that are done internally by the function package
  2730 and makes them available separately.  See
  2731 src/HOL/ex/Induction_Scheme.thy for examples.
  2732 
  2733 * More flexible generation of measure functions for termination
  2734 proofs: Measure functions can be declared by proving a rule of the
  2735 form "is_measure f" and giving it the [measure_function] attribute.
  2736 The "is_measure" predicate is logically meaningless (always true), and
  2737 just guides the heuristic.  To find suitable measure functions, the
  2738 termination prover sets up the goal "is_measure ?f" of the appropriate
  2739 type and generates all solutions by prolog-style backwards proof using
  2740 the declared rules.
  2741 
  2742 This setup also deals with rules like 
  2743 
  2744   "is_measure f ==> is_measure (list_size f)"
  2745 
  2746 which accommodates nested datatypes that recurse through lists.
  2747 Similar rules are predeclared for products and option types.
  2748 
  2749 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2750 
  2751   INCOMPATIBILITIES:
  2752 
  2753   - Definitions of overloaded constants on sets have to be replaced by
  2754     definitions on => and bool.
  2755 
  2756   - Some definitions of overloaded operators on sets can now be proved
  2757     using the definitions of the operators on => and bool.  Therefore,
  2758     the following theorems have been renamed:
  2759 
  2760       subset_def   -> subset_eq
  2761       psubset_def  -> psubset_eq
  2762       set_diff_def -> set_diff_eq
  2763       Compl_def    -> Compl_eq
  2764       Sup_set_def  -> Sup_set_eq
  2765       Inf_set_def  -> Inf_set_eq
  2766       sup_set_def  -> sup_set_eq
  2767       inf_set_def  -> inf_set_eq
  2768 
  2769   - Due to the incompleteness of the HO unification algorithm, some
  2770     rules such as subst may require manual instantiation, if some of
  2771     the unknowns in the rule is a set.
  2772 
  2773   - Higher order unification and forward proofs:
  2774     The proof pattern
  2775 
  2776       have "P (S::'a set)" <...>
  2777       then have "EX S. P S" ..
  2778 
  2779     no longer works (due to the incompleteness of the HO unification
  2780     algorithm) and must be replaced by the pattern
  2781 
  2782       have "EX S. P S"
  2783       proof
  2784         show "P S" <...>
  2785       qed
  2786 
  2787   - Calculational reasoning with subst (or similar rules):
  2788     The proof pattern
  2789 
  2790       have "P (S::'a set)" <...>
  2791       also have "S = T" <...>
  2792       finally have "P T" .
  2793 
  2794     no longer works (for similar reasons as the previous example) and
  2795     must be replaced by something like
  2796 
  2797       have "P (S::'a set)" <...>
  2798       moreover have "S = T" <...>
  2799       ultimately have "P T" by simp
  2800 
  2801   - Tactics or packages written in ML code:
  2802     Code performing pattern matching on types via
  2803 
  2804       Type ("set", [T]) => ...
  2805 
  2806     must be rewritten. Moreover, functions like strip_type or
  2807     binder_types no longer return the right value when applied to a
  2808     type of the form
  2809 
  2810       T1 => ... => Tn => U => bool
  2811 
  2812     rather than
  2813 
  2814       T1 => ... => Tn => U set
  2815 
  2816 * Merged theories Wellfounded_Recursion, Accessible_Part and
  2817 Wellfounded_Relations to theory Wellfounded.
  2818 
  2819 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  2820 
  2821 * Class finite no longer treats UNIV as class parameter.  Use class
  2822 enum from theory Library/Enum instead to achieve a similar effect.
  2823 INCOMPATIBILITY.
  2824 
  2825 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  2826 and "Cons".  INCOMPATIBILITY.
  2827 
  2828 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  2829 Potential INCOMPATIBILITY.
  2830 
  2831 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  2832 injective_fst_snd removed, use split_eta and prod_eqI instead.
  2833 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  2834 
  2835 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  2836 the same name in theory Orderings:
  2837 
  2838   less_trans
  2839   less_linear
  2840   le_imp_less_or_eq
  2841   le_less_trans
  2842   less_le_trans
  2843   less_not_sym
  2844   less_asym
  2845 
  2846 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  2847 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  2848 and different variable names.
  2849 
  2850 * Library/Option_ord.thy: Canonical order on option type.
  2851 
  2852 * Library/RBT.thy: Red-black trees, an efficient implementation of
  2853 finite maps.
  2854 
  2855 * Library/Countable.thy: Type class for countable types.
  2856 
  2857 * Theory Int: The representation of numerals has changed.  The infix
  2858 operator BIT and the bit datatype with constructors B0 and B1 have
  2859 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  2860 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  2861 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  2862 accordingly.
  2863 
  2864 * Theory Nat: definition of <= and < on natural numbers no longer
  2865 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  2866 le_def and less_def have disappeared.  Consider lemmas not_less
  2867 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  2868 
  2869 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  2870 (whose purpose mainly is for various fold_set functionals) have been
  2871 abandoned in favor of the existing algebraic classes
  2872 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  2873 lower_semilattice (resp. upper_semilattice) and linorder.
  2874 INCOMPATIBILITY.
  2875 
  2876 * Theory Transitive_Closure: induct and cases rules now declare proper
  2877 case_names ("base" and "step").  INCOMPATIBILITY.
  2878 
  2879 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  2880 lattices.  The form set-specific version is available as
  2881 Inductive.lfp_ordinal_induct_set.
  2882 
  2883 * Renamed theorems "power.simps" to "power_int.simps".
  2884 INCOMPATIBILITY.
  2885 
  2886 * Class semiring_div provides basic abstract properties of semirings
  2887 with division and modulo operations.  Subsumes former class dvd_mod.
  2888 
  2889 * Merged theories IntDef, Numeral and IntArith into unified theory
  2890 Int.  INCOMPATIBILITY.
  2891 
  2892 * Theory Library/Code_Index: type "index" now represents natural
  2893 numbers rather than integers.  INCOMPATIBILITY.
  2894 
  2895 * New class "uminus" with operation "uminus" (split of from class
  2896 "minus" which now only has operation "minus", binary).
  2897 INCOMPATIBILITY.
  2898 
  2899 * Constants "card", "internal_split", "option_map" now with authentic
  2900 syntax.  INCOMPATIBILITY.
  2901 
  2902 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  2903 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  2904 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  2905 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  2906 Sup_set_def, le_def, less_def, option_map_def now with object
  2907 equality.  INCOMPATIBILITY.
  2908 
  2909 * Records. Removed K_record, and replaced it by pure lambda term
  2910 %x. c. The simplifier setup is now more robust against eta expansion.
  2911 INCOMPATIBILITY: in cases explicitly referring to K_record.
  2912 
  2913 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  2914 
  2915 * Library/ListVector: new theory of arithmetic vector operations.
  2916 
  2917 * Library/Order_Relation: new theory of various orderings as sets of
  2918 pairs.  Defines preorders, partial orders, linear orders and
  2919 well-orders on sets and on types.
  2920 
  2921 
  2922 *** ZF ***
  2923 
  2924 * Renamed some theories to allow to loading both ZF and HOL in the
  2925 same session:
  2926 
  2927   Datatype  -> Datatype_ZF
  2928   Inductive -> Inductive_ZF
  2929   Int       -> Int_ZF
  2930   IntDiv    -> IntDiv_ZF
  2931   Nat       -> Nat_ZF
  2932   List      -> List_ZF
  2933   Main      -> Main_ZF
  2934 
  2935 INCOMPATIBILITY: ZF theories that import individual theories below
  2936 Main might need to be adapted.  Regular theory Main is still
  2937 available, as trivial extension of Main_ZF.
  2938 
  2939 
  2940 *** ML ***
  2941 
  2942 * ML within Isar: antiquotation @{const name} or @{const
  2943 name(typargs)} produces statically-checked Const term.
  2944 
  2945 * Functor NamedThmsFun: data is available to the user as dynamic fact
  2946 (of the same name).  Removed obsolete print command.
  2947 
  2948 * Removed obsolete "use_legacy_bindings" function.
  2949 
  2950 * The ``print mode'' is now a thread-local value derived from a global
  2951 template (the former print_mode reference), thus access becomes
  2952 non-critical.  The global print_mode reference is for session
  2953 management only; user-code should use print_mode_value,
  2954 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  2955 
  2956 * Functions system/system_out provide a robust way to invoke external
  2957 shell commands, with propagation of interrupts (requires Poly/ML
  2958 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  2959 
  2960 
  2961 *** System ***
  2962 
  2963 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  2964 in accordance with Proof General 3.7, which prefers GNU emacs.
  2965 
  2966 * isatool tty runs Isabelle process with plain tty interaction;
  2967 optional line editor may be specified via ISABELLE_LINE_EDITOR
  2968 setting, the default settings attempt to locate "ledit" and "rlwrap".
  2969 
  2970 * isatool browser now works with Cygwin as well, using general
  2971 "javapath" function defined in Isabelle process environment.
  2972 
  2973 * YXML notation provides a simple and efficient alternative to
  2974 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  2975 isatool yxml as described in the Isabelle system manual.
  2976 
  2977 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  2978 provides general wrapper for managing an Isabelle process in a robust
  2979 fashion, with ``cooked'' output from stdin/stderr.
  2980 
  2981 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  2982 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  2983 
  2984 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  2985 way of changing the user's settings is via
  2986 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  2987 script.
  2988 
  2989 * Multithreading.max_threads := 0 refers to the number of actual CPU
  2990 cores of the underlying machine, which is a good starting point for
  2991 optimal performance tuning.  The corresponding usedir option -M allows
  2992 "max" as an alias for "0".  WARNING: does not work on certain versions
  2993 of Mac OS (with Poly/ML 5.1).
  2994 
  2995 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  2996 adverse effect of Isabelle flooding interactive front-ends (notably
  2997 ProofGeneral / XEmacs).
  2998 
  2999 
  3000 
  3001 New in Isabelle2007 (November 2007)
  3002 -----------------------------------
  3003 
  3004 *** General ***
  3005 
  3006 * More uniform information about legacy features, notably a
  3007 warning/error of "Legacy feature: ...", depending on the state of the
  3008 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3009 legacy features will disappear eventually.
  3010 
  3011 * Theory syntax: the header format ``theory A = B + C:'' has been
  3012 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3013 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3014 
  3015 * Theory syntax: the old non-Isar theory file format has been
  3016 discontinued altogether.  Note that ML proof scripts may still be used
  3017 with Isar theories; migration is usually quite simple with the ML
  3018 function use_legacy_bindings.  INCOMPATIBILITY.
  3019 
  3020 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3021 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3022 quotes.
  3023 
  3024 * Theory loader: be more serious about observing the static theory
  3025 header specifications (including optional directories), but not the
  3026 accidental file locations of previously successful loads.  The strict
  3027 update policy of former update_thy is now already performed by
  3028 use_thy, so the former has been removed; use_thys updates several
  3029 theories simultaneously, just as 'imports' within a theory header
  3030 specification, but without merging the results.  Potential
  3031 INCOMPATIBILITY: may need to refine theory headers and commands
  3032 ROOT.ML which depend on load order.
  3033 
  3034 * Theory loader: optional support for content-based file
  3035 identification, instead of the traditional scheme of full physical
  3036 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3037 (cf. the system manual).  The new scheme allows to work with
  3038 non-finished theories in persistent session images, such that source
  3039 files may be moved later on without requiring reloads.
  3040 
  3041 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3042 file (with the same base name as the theory) are considered a legacy
  3043 feature, which will disappear eventually. Even now, the theory loader
  3044 no longer maintains dependencies on such files.
  3045 
  3046 * Syntax: the scope for resolving ambiguities via type-inference is
  3047 now limited to individual terms, instead of whole simultaneous
  3048 specifications as before. This greatly reduces the complexity of the
  3049 syntax module and improves flexibility by separating parsing and
  3050 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3051 'fixes' etc.) are required in rare situations.
  3052 
  3053 * Syntax: constants introduced by new-style packages ('definition',
  3054 'abbreviation' etc.) are passed through the syntax module in
  3055 ``authentic mode''. This means that associated mixfix annotations
  3056 really stick to such constants, independently of potential name space
  3057 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3058 trees are represented slightly differently, may need to adapt syntax
  3059 translations accordingly. Use CONST marker in 'translations' and
  3060 @{const_syntax} antiquotation in 'parse_translation' etc.
  3061 
  3062 * Legacy goal package: reduced interface to the bare minimum required
  3063 to keep existing proof scripts running.  Most other user-level
  3064 functions are now part of the OldGoals structure, which is *not* open
  3065 by default (consider isatool expandshort before open OldGoals).
  3066 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3067 these tend to cause confusion about the actual goal (!) context being
  3068 used here, which is not necessarily the same as the_context().
  3069 
  3070 * Command 'find_theorems': supports "*" wild-card in "name:"
  3071 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3072 support a specific search form (see ProofGeneral/CHANGES).
  3073 
  3074 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3075 by default, which means that "prems" (and also "fixed variables") are
  3076 suppressed from proof state output.  Note that the ProofGeneral
  3077 settings mechanism allows to change and save options persistently, but
  3078 older versions of Isabelle will fail to start up if a negative prems
  3079 limit is imposed.
  3080 
  3081 * Local theory targets may be specified by non-nested blocks of
  3082 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3083 contain definitions, theorems etc., including any derived mechanism
  3084 that has been implemented on top of these primitives.  This concept
  3085 generalizes the existing ``theorem (in ...)'' towards more versatility
  3086 and scalability.
  3087 
  3088 * Proof General interface: proper undo of final 'end' command;
  3089 discontinued Isabelle/classic mode (ML proof scripts).
  3090 
  3091 
  3092 *** Document preparation ***
  3093 
  3094 * Added antiquotation @{theory name} which prints the given name,
  3095 after checking that it refers to a valid ancestor theory in the
  3096 current context.
  3097 
  3098 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3099 check the given source text as ML type/structure, printing verbatim.
  3100 
  3101 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3102 "c args == rhs" given in the current context.  (Any number of
  3103 arguments may be given on the LHS.)
  3104 
  3105 
  3106 *** Pure ***
  3107 
  3108 * The 'class' package offers a combination of axclass and locale to
  3109 achieve Haskell-like type classes in Isabelle.  Definitions and
  3110 theorems within a class context produce both relative results (with
  3111 implicit parameters according to the locale context), and polymorphic
  3112 constants with qualified polymorphism (according to the class
  3113 context).  Within the body context of a 'class' target, a separate
  3114 syntax layer ("user space type system") takes care of converting
  3115 between global polymorphic consts and internal locale representation.
  3116 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3117 "isatool doc classes" provides a tutorial.
  3118 
  3119 * Generic code generator framework allows to generate executable
  3120 code for ML and Haskell (including Isabelle classes).  A short usage
  3121 sketch:
  3122 
  3123     internal compilation:
  3124         export_code <list of constants (term syntax)> in SML
  3125     writing SML code to a file:
  3126         export_code <list of constants (term syntax)> in SML <filename>
  3127     writing OCaml code to a file:
  3128         export_code <list of constants (term syntax)> in OCaml <filename>
  3129     writing Haskell code to a bunch of files:
  3130         export_code <list of constants (term syntax)> in Haskell <filename>
  3131 
  3132     evaluating closed propositions to True/False using code generation:
  3133         method ``eval''
  3134 
  3135 Reasonable default setup of framework in HOL.
  3136 
  3137 Theorem attributs for selecting and transforming function equations theorems:
  3138 
  3139     [code fun]:        select a theorem as function equation for a specific constant
  3140     [code fun del]:    deselect a theorem as function equation for a specific constant
  3141     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3142     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3143 
  3144 User-defined serializations (target in {SML, OCaml, Haskell}):
  3145 
  3146     code_const <and-list of constants (term syntax)>
  3147       {(target) <and-list of const target syntax>}+
  3148 
  3149     code_type <and-list of type constructors>
  3150       {(target) <and-list of type target syntax>}+
  3151 
  3152     code_instance <and-list of instances>
  3153       {(target)}+
  3154         where instance ::= <type constructor> :: <class>
  3155 
  3156     code_class <and_list of classes>
  3157       {(target) <and-list of class target syntax>}+
  3158         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3159 
  3160 code_instance and code_class only are effective to target Haskell.
  3161 
  3162 For example usage see src/HOL/ex/Codegenerator.thy and
  3163 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3164 generation from Isabelle/HOL theories is available via "isatool doc
  3165 codegen".
  3166 
  3167 * Code generator: consts in 'consts_code' Isar commands are now
  3168 referred to by usual term syntax (including optional type
  3169 annotations).
  3170 
  3171 * Command 'no_translations' removes translation rules from theory
  3172 syntax.
  3173 
  3174 * Overloaded definitions are now actually checked for acyclic
  3175 dependencies.  The overloading scheme is slightly more general than
  3176 that of Haskell98, although Isabelle does not demand an exact
  3177 correspondence to type class and instance declarations.
  3178 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3179 exotic versions of overloading -- at the discretion of the user!
  3180 
  3181 Polymorphic constants are represented via type arguments, i.e. the
  3182 instantiation that matches an instance against the most general
  3183 declaration given in the signature.  For example, with the declaration
  3184 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3185 as c(nat).  Overloading is essentially simultaneous structural
  3186 recursion over such type arguments.  Incomplete specification patterns
  3187 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3188 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3189 Command 'print_theory' outputs the normalized system of recursive
  3190 equations, see section "definitions".
  3191 
  3192 * Configuration options are maintained within the theory or proof
  3193 context (with name and type bool/int/string), providing a very simple
  3194 interface to a poor-man's version of general context data.  Tools may
  3195 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3196 these values using Config.get etc.  Users may change options via an
  3197 associated attribute of the same name.  This form of context
  3198 declaration works particularly well with commands 'declare' or
  3199 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3200 very easy to avoid global references, which would not observe Isar
  3201 toplevel undo/redo and fail to work with multithreading.
  3202 
  3203 Various global ML references of Pure and HOL have been turned into
  3204 configuration options:
  3205 
  3206   Unify.search_bound		unify_search_bound
  3207   Unify.trace_bound		unify_trace_bound
  3208   Unify.trace_simp		unify_trace_simp
  3209   Unify.trace_types		unify_trace_types
  3210   Simplifier.simp_depth_limit	simp_depth_limit
  3211   Blast.depth_limit		blast_depth_limit
  3212   DatatypeProp.dtK		datatype_distinctness_limit
  3213   fast_arith_neq_limit  	fast_arith_neq_limit
  3214   fast_arith_split_limit	fast_arith_split_limit
  3215 
  3216 * Named collections of theorems may be easily installed as context
  3217 data using the functor NamedThmsFun (see also
  3218 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3219 attributes; there is also a toplevel print command.  This facility is
  3220 just a common case of general context data, which is the preferred way
  3221 for anything more complex than just a list of facts in canonical
  3222 order.
  3223 
  3224 * Isar: command 'declaration' augments a local theory by generic
  3225 declaration functions written in ML.  This enables arbitrary content
  3226 being added to the context, depending on a morphism that tells the
  3227 difference of the original declaration context wrt. the application
  3228 context encountered later on.
  3229 
  3230 * Isar: proper interfaces for simplification procedures.  Command
  3231 'simproc_setup' declares named simprocs (with match patterns, and body
  3232 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3233 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3234 
  3235 * Isar: an extra pair of brackets around attribute declarations
  3236 abbreviates a theorem reference involving an internal dummy fact,
  3237 which will be ignored later --- only the effect of the attribute on
  3238 the background context will persist.  This form of in-place
  3239 declarations is particularly useful with commands like 'declare' and
  3240 'using', for example ``have A using [[simproc a]] by simp''.
  3241 
  3242 * Isar: method "assumption" (and implicit closing of subproofs) now
  3243 takes simple non-atomic goal assumptions into account: after applying
  3244 an assumption as a rule the resulting subgoals are solved by atomic
  3245 assumption steps.  This is particularly useful to finish 'obtain'
  3246 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3247 without referring to the original premise "!!x. P x ==> thesis" in the
  3248 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3249 more permissive.
  3250 
  3251 * Isar: implicit use of prems from the Isar proof context is
  3252 considered a legacy feature.  Common applications like ``have A .''
  3253 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3254 referencing facts explicitly here improves readability and
  3255 maintainability of proof texts.
  3256 
  3257 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3258 the obtained context from the course of reasoning!  For example:
  3259 
  3260   assume "EX x y. A x & B y"   -- "any previous fact"
  3261   then guess x and y by clarify
  3262 
  3263 This technique is potentially adventurous, depending on the facts and
  3264 proof tools being involved here.
  3265 
  3266 * Isar: known facts from the proof context may be specified as literal
  3267 propositions, using ASCII back-quote syntax.  This works wherever
  3268 named facts used to be allowed so far, in proof commands, proof
  3269 methods, attributes etc.  Literal facts are retrieved from the context
  3270 according to unification of type and term parameters.  For example,
  3271 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3272 theorems in the current context, then these are valid literal facts:
  3273 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3274 
  3275 There is also a proof method "fact" which does the same composition
  3276 for explicit goal states, e.g. the following proof texts coincide with
  3277 certain special cases of literal facts:
  3278 
  3279   have "A" by fact                 ==  note `A`
  3280   have "A ==> B" by fact           ==  note `A ==> B`
  3281   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3282   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3283 
  3284 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3285 outer syntax.  Thus symbolic identifiers may be used without
  3286 additional white space in declarations like this: ``assume *: A''.
  3287 
  3288 * Isar: 'print_facts' prints all local facts of the current context,
  3289 both named and unnamed ones.
  3290 
  3291 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3292 
  3293   def x == "t" and y == "u"
  3294 
  3295 * Isar: added command 'unfolding', which is structurally similar to
  3296 'using', but affects both the goal state and facts by unfolding given
  3297 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3298 'unfolded' attribute may be replaced by first-class proof text.
  3299 
  3300 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3301 and command 'unfolding' now all support object-level equalities
  3302 (potentially conditional).  The underlying notion of rewrite rule is
  3303 analogous to the 'rule_format' attribute, but *not* that of the
  3304 Simplifier (which is usually more generous).
  3305 
  3306 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3307 premises of a theorem by n. Useful in conjunction with drule.
  3308 
  3309 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3310 method expression within a sandbox consisting of the first N
  3311 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3312 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3313 simplifies all new goals that emerge from applying rule foo to the
  3314 originally first one.
  3315 
  3316 * Isar: schematic goals are no longer restricted to higher-order
  3317 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3318 expected.
  3319 
  3320 * Isar: the conclusion of a long theorem statement is now either
  3321 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3322 (essentially a disjunction of cases with local parameters and
  3323 assumptions).  The latter allows to express general elimination rules
  3324 adequately; in this notation common elimination rules look like this:
  3325 
  3326   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3327     assumes "EX x. P x"
  3328     obtains x where "P x"
  3329 
  3330   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3331     assumes "A & B"
  3332     obtains A and B
  3333 
  3334   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3335     assumes "A | B"
  3336     obtains
  3337       A
  3338     | B
  3339 
  3340 The subsequent classical rules even refer to the formal "thesis"
  3341 explicitly:
  3342 
  3343   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3344     obtains "~ thesis"
  3345 
  3346   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3347     obtains "thesis ==> something"
  3348 
  3349 The actual proof of an 'obtains' statement is analogous to that of the
  3350 Isar proof element 'obtain', only that there may be several cases.
  3351 Optional case names may be specified in parentheses; these will be
  3352 available both in the present proof and as annotations in the
  3353 resulting rule, for later use with the 'cases' method (cf. attribute
  3354 case_names).
  3355 
  3356 * Isar: the assumptions of a long theorem statement are available as
  3357 "assms" fact in the proof context.  This is more appropriate than the
  3358 (historical) "prems", which refers to all assumptions of the current
  3359 context, including those from the target locale, proof body etc.
  3360 
  3361 * Isar: 'print_statement' prints theorems from the current theory or
  3362 proof context in long statement form, according to the syntax of a
  3363 top-level lemma.
  3364 
  3365 * Isar: 'obtain' takes an optional case name for the local context
  3366 introduction rule (default "that").
  3367 
  3368 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3369 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3370 to occur.
  3371 
  3372 * Pure: syntax "CONST name" produces a fully internalized constant
  3373 according to the current context.  This is particularly useful for
  3374 syntax translations that should refer to internal constant
  3375 representations independently of name spaces.
  3376 
  3377 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3378 instead of "FOO ". This allows multiple binder declarations to coexist
  3379 in the same context.  INCOMPATIBILITY.
  3380 
  3381 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3382 primitive that also works in a locale context (both for constants and
  3383 fixed variables). Type declaration and internal syntactic representation
  3384 of given constants retrieved from the context. Likewise, the
  3385 'no_notation' command allows to remove given syntax annotations from the
  3386 current context.
  3387 
  3388 * Isar/locales: new derived specification elements 'axiomatization',
  3389 'definition', 'abbreviation', which support type-inference, admit
  3390 object-level specifications (equality, equivalence).  See also the
  3391 isar-ref manual.  Examples:
  3392 
  3393   axiomatization
  3394     eq  (infix "===" 50) where
  3395     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3396 
  3397   definition "f x y = x + y + 1"
  3398   definition g where "g x = f x x"
  3399 
  3400   abbreviation
  3401     neq  (infix "=!=" 50) where
  3402     "x =!= y == ~ (x === y)"
  3403 
  3404 These specifications may be also used in a locale context.  Then the
  3405 constants being introduced depend on certain fixed parameters, and the
  3406 constant name is qualified by the locale base name.  An internal
  3407 abbreviation takes care for convenient input and output, making the
  3408 parameters implicit and using the original short name.  See also
  3409 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3410 entities from a monomorphic theory.
  3411 
  3412 Presently, abbreviations are only available 'in' a target locale, but
  3413 not inherited by general import expressions.  Also note that
  3414 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3415 'translations' in common applications.  The "no_abbrevs" print mode
  3416 prevents folding of abbreviations in term output.
  3417 
  3418 Concrete syntax is attached to specified constants in internal form,
  3419 independently of name spaces.  The parse tree representation is
  3420 slightly different -- use 'notation' instead of raw 'syntax', and
  3421 'translations' with explicit "CONST" markup to accommodate this.
  3422 
  3423 * Pure/Isar: unified syntax for new-style specification mechanisms
  3424 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3425 full type inference and dummy patterns ("_").  For example:
  3426 
  3427   definition "K x _ = x"
  3428 
  3429   inductive conj for A B
  3430   where "A ==> B ==> conj A B"
  3431 
  3432 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3433 the current context.  Print mode "no_abbrevs" prevents inversion of
  3434 abbreviations on output.
  3435 
  3436 * Isar/locales: improved parameter handling: use of locales "var" and
  3437 "struct" no longer necessary; - parameter renamings are no longer
  3438 required to be injective.  For example, this allows to define
  3439 endomorphisms as locale endom = homom mult mult h.
  3440 
  3441 * Isar/locales: changed the way locales with predicates are defined.
  3442 Instead of accumulating the specification, the imported expression is
  3443 now an interpretation.  INCOMPATIBILITY: different normal form of
  3444 locale expressions.  In particular, in interpretations of locales with
  3445 predicates, goals repesenting already interpreted fragments are not
  3446 removed automatically.  Use methods `intro_locales' and
  3447 `unfold_locales'; see below.
  3448 
  3449 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3450 provide backward reasoning on locales predicates.  The methods are
  3451 aware of interpretations and discharge corresponding goals.
  3452 `intro_locales' is less aggressive then `unfold_locales' and does not
  3453 unfold predicates to assumptions.
  3454 
  3455 * Isar/locales: the order in which locale fragments are accumulated
  3456 has changed.  This enables to override declarations from fragments due
  3457 to interpretations -- for example, unwanted simp rules.
  3458 
  3459 * Isar/locales: interpretation in theories and proof contexts has been
  3460 extended.  One may now specify (and prove) equations, which are
  3461 unfolded in interpreted theorems.  This is useful for replacing
  3462 defined concepts (constants depending on locale parameters) by
  3463 concepts already existing in the target context.  Example:
  3464 
  3465   interpretation partial_order ["op <= :: [int, int] => bool"]
  3466     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3467 
  3468 Typically, the constant `partial_order.less' is created by a
  3469 definition specification element in the context of locale
  3470 partial_order.
  3471 
  3472 * Method "induct": improved internal context management to support
  3473 local fixes and defines on-the-fly. Thus explicit meta-level
  3474 connectives !!  and ==> are rarely required anymore in inductive goals
  3475 (using object-logic connectives for this purpose has been long
  3476 obsolete anyway). Common proof patterns are explained in
  3477 src/HOL/Induct/Common_Patterns.thy, see also
  3478 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3479 examples.
  3480 
  3481 * Method "induct": improved handling of simultaneous goals. Instead of
  3482 introducing object-level conjunction, the statement is now split into
  3483 several conclusions, while the corresponding symbolic cases are nested
  3484 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3485 see src/HOL/Induct/Common_Patterns.thy, for example.
  3486 
  3487 * Method "induct": mutual induction rules are now specified as a list
  3488 of rule sharing the same induction cases. HOL packages usually provide
  3489 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3490 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3491 mutual induction rules differently, i.e. like this:
  3492 
  3493   (induct rule: foo_bar.inducts)
  3494   (induct set: foo bar)
  3495   (induct pred: foo bar)
  3496   (induct type: foo bar)
  3497 
  3498 The ML function ProjectRule.projections turns old-style rules into the
  3499 new format.
  3500 
  3501 * Method "coinduct": dual of induction, see
  3502 src/HOL/Library/Coinductive_List.thy for various examples.
  3503 
  3504 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3505 considered a legacy feature.
  3506 
  3507 * Attribute "symmetric" produces result with standardized schematic
  3508 variables (index 0).  Potential INCOMPATIBILITY.
  3509 
  3510 * Simplifier: by default the simplifier trace only shows top level
  3511 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3512 default. Thus there is less danger of being flooded by the trace. The
  3513 trace indicates where parts have been suppressed.
  3514   
  3515 * Provers/classical: removed obsolete classical version of elim_format
  3516 attribute; classical elim/dest rules are now treated uniformly when
  3517 manipulating the claset.
  3518 
  3519 * Provers/classical: stricter checks to ensure that supplied intro,
  3520 dest and elim rules are well-formed; dest and elim rules must have at
  3521 least one premise.
  3522 
  3523 * Provers/classical: attributes dest/elim/intro take an optional
  3524 weight argument for the rule (just as the Pure versions).  Weights are
  3525 ignored by automated tools, but determine the search order of single
  3526 rule steps.
  3527 
  3528 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3529 where the body does not mention the bound variable.  Note that dummy
  3530 patterns implicitly depend on their context of bounds, which makes
  3531 "{_. _}" match any set comprehension as expected.  Potential
  3532 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3533 constant "_idtdummy" in the binding position.
  3534 
  3535 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3536 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3537 for example "A -> B" => "Pi A (%_. B)".
  3538 
  3539 * Pure: 'class_deps' command visualizes the subclass relation, using
  3540 the graph browser tool.
  3541 
  3542 * Pure: 'print_theory' now suppresses certain internal declarations by
  3543 default; use '!' option for full details.
  3544 
  3545 
  3546 *** HOL ***
  3547 
  3548 * Method "metis" proves goals by applying the Metis general-purpose
  3549 resolution prover (see also http://gilith.com/software/metis/).
  3550 Examples are in the directory MetisExamples.  WARNING: the
  3551 Isabelle/HOL-Metis integration does not yet work properly with
  3552 multi-threading.
  3553   
  3554 * Command 'sledgehammer' invokes external automatic theorem provers as
  3555 background processes.  It generates calls to the "metis" method if
  3556 successful. These can be pasted into the proof.  Users do not have to
  3557 wait for the automatic provers to return.  WARNING: does not really
  3558 work with multi-threading.
  3559 
  3560 * New "auto_quickcheck" feature tests outermost goal statements for
  3561 potential counter-examples.  Controlled by ML references
  3562 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3563 5000 milliseconds).  Fails silently if statements is outside of
  3564 executable fragment, or any other codgenerator problem occurs.
  3565 
  3566 * New constant "undefined" with axiom "undefined x = undefined".
  3567 
  3568 * Added class "HOL.eq", allowing for code generation with polymorphic
  3569 equality.
  3570 
  3571 * Some renaming of class constants due to canonical name prefixing in
  3572 the new 'class' package:
  3573 
  3574     HOL.abs ~> HOL.abs_class.abs
  3575     HOL.divide ~> HOL.divide_class.divide
  3576     0 ~> HOL.zero_class.zero
  3577     1 ~> HOL.one_class.one
  3578     op + ~> HOL.plus_class.plus
  3579     op - ~> HOL.minus_class.minus
  3580     uminus ~> HOL.minus_class.uminus
  3581     op * ~> HOL.times_class.times
  3582     op < ~> HOL.ord_class.less
  3583     op <= > HOL.ord_class.less_eq
  3584     Nat.power ~> Power.power_class.power
  3585     Nat.size ~> Nat.size_class.size
  3586     Numeral.number_of ~> Numeral.number_class.number_of
  3587     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3588     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3589     Orderings.min ~> Orderings.ord_class.min
  3590     Orderings.max ~> Orderings.ord_class.max
  3591     Divides.op div ~> Divides.div_class.div
  3592     Divides.op mod ~> Divides.div_class.mod
  3593     Divides.op dvd ~> Divides.div_class.dvd
  3594 
  3595 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3596 
  3597 a) User-defined constants using any of the names "plus", "minus",
  3598 "times", "less" or "less_eq". The standard syntax translations for
  3599 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3600 names.
  3601 
  3602 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3603 INCOMPATIBILITY: use more specific names.
  3604 
  3605 c) Permutative equations (e.g. "a + b = b + a")
  3606 Since the change of names also changes the order of terms, permutative
  3607 rewrite rules may get applied in a different order. Experience shows
  3608 that this is rarely the case (only two adaptions in the whole Isabelle
  3609 distribution).  INCOMPATIBILITY: rewrite proofs
  3610 
  3611 d) ML code directly refering to constant names
  3612 This in general only affects hand-written proof tactics, simprocs and
  3613 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3614 Consider using @{const_name} antiquotation.
  3615 
  3616 * New class "default" with associated constant "default".
  3617 
  3618 * Function "sgn" is now overloaded and available on int, real, complex
  3619 (and other numeric types), using class "sgn".  Two possible defs of
  3620 sgn are given as equational assumptions in the classes sgn_if and
  3621 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3622 INCOMPATIBILITY.
  3623 
  3624 * Locale "partial_order" now unified with class "order" (cf. theory
  3625 Orderings), added parameter "less".  INCOMPATIBILITY.
  3626 
  3627 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3628 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3629 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3630 
  3631 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3632 changed order of proof goals in instance proofs.
  3633 
  3634 * The transitivity reasoner for partial and linear orders is set up
  3635 for classes "order" and "linorder".  Instances of the reasoner are available
  3636 in all contexts importing or interpreting the corresponding locales.
  3637 Method "order" invokes the reasoner separately; the reasoner
  3638 is also integrated with the Simplifier as a solver.  Diagnostic
  3639 command 'print_orders' shows the available instances of the reasoner
  3640 in the current context.
  3641 
  3642 * Localized monotonicity predicate in theory "Orderings"; integrated
  3643 lemmas max_of_mono and min_of_mono with this predicate.
  3644 INCOMPATIBILITY.
  3645 
  3646 * Formulation of theorem "dense" changed slightly due to integration
  3647 with new class dense_linear_order.
  3648 
  3649 * Uniform lattice theory development in HOL.
  3650 
  3651     constants "meet" and "join" now named "inf" and "sup"
  3652     constant "Meet" now named "Inf"
  3653 
  3654     classes "meet_semilorder" and "join_semilorder" now named
  3655       "lower_semilattice" and "upper_semilattice"
  3656     class "lorder" now named "lattice"
  3657     class "comp_lat" now named "complete_lattice"
  3658 
  3659     Instantiation of lattice classes allows explicit definitions
  3660     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3661 
  3662   INCOMPATIBILITY.  Theorem renames:
  3663 
  3664     meet_left_le            ~> inf_le1
  3665     meet_right_le           ~> inf_le2
  3666     join_left_le            ~> sup_ge1
  3667     join_right_le           ~> sup_ge2
  3668     meet_join_le            ~> inf_sup_ord
  3669     le_meetI                ~> le_infI
  3670     join_leI                ~> le_supI
  3671     le_meet                 ~> le_inf_iff
  3672     le_join                 ~> ge_sup_conv
  3673     meet_idempotent         ~> inf_idem
  3674     join_idempotent         ~> sup_idem
  3675     meet_comm               ~> inf_commute
  3676     join_comm               ~> sup_commute
  3677     meet_leI1               ~> le_infI1
  3678     meet_leI2               ~> le_infI2
  3679     le_joinI1               ~> le_supI1
  3680     le_joinI2               ~> le_supI2
  3681     meet_assoc              ~> inf_assoc
  3682     join_assoc              ~> sup_assoc
  3683     meet_left_comm          ~> inf_left_commute
  3684     meet_left_idempotent    ~> inf_left_idem
  3685     join_left_comm          ~> sup_left_commute
  3686     join_left_idempotent    ~> sup_left_idem
  3687     meet_aci                ~> inf_aci
  3688     join_aci                ~> sup_aci
  3689     le_def_meet             ~> le_iff_inf
  3690     le_def_join             ~> le_iff_sup
  3691     join_absorp2            ~> sup_absorb2
  3692     join_absorp1            ~> sup_absorb1
  3693     meet_absorp1            ~> inf_absorb1
  3694     meet_absorp2            ~> inf_absorb2
  3695     meet_join_absorp        ~> inf_sup_absorb
  3696     join_meet_absorp        ~> sup_inf_absorb
  3697     distrib_join_le         ~> distrib_sup_le
  3698     distrib_meet_le         ~> distrib_inf_le
  3699 
  3700     add_meet_distrib_left   ~> add_inf_distrib_left
  3701     add_join_distrib_left   ~> add_sup_distrib_left
  3702     is_join_neg_meet        ~> is_join_neg_inf
  3703     is_meet_neg_join        ~> is_meet_neg_sup
  3704     add_meet_distrib_right  ~> add_inf_distrib_right
  3705     add_join_distrib_right  ~> add_sup_distrib_right
  3706     add_meet_join_distribs  ~> add_sup_inf_distribs
  3707     join_eq_neg_meet        ~> sup_eq_neg_inf
  3708     meet_eq_neg_join        ~> inf_eq_neg_sup
  3709     add_eq_meet_join        ~> add_eq_inf_sup
  3710     meet_0_imp_0            ~> inf_0_imp_0
  3711     join_0_imp_0            ~> sup_0_imp_0
  3712     meet_0_eq_0             ~> inf_0_eq_0
  3713     join_0_eq_0             ~> sup_0_eq_0
  3714     neg_meet_eq_join        ~> neg_inf_eq_sup
  3715     neg_join_eq_meet        ~> neg_sup_eq_inf
  3716     join_eq_if              ~> sup_eq_if
  3717 
  3718     mono_meet               ~> mono_inf
  3719     mono_join               ~> mono_sup
  3720     meet_bool_eq            ~> inf_bool_eq
  3721     join_bool_eq            ~> sup_bool_eq
  3722     meet_fun_eq             ~> inf_fun_eq
  3723     join_fun_eq             ~> sup_fun_eq
  3724     meet_set_eq             ~> inf_set_eq
  3725     join_set_eq             ~> sup_set_eq
  3726     meet1_iff               ~> inf1_iff
  3727     meet2_iff               ~> inf2_iff
  3728     meet1I                  ~> inf1I
  3729     meet2I                  ~> inf2I
  3730     meet1D1                 ~> inf1D1
  3731     meet2D1                 ~> inf2D1
  3732     meet1D2                 ~> inf1D2
  3733     meet2D2                 ~> inf2D2
  3734     meet1E                  ~> inf1E
  3735     meet2E                  ~> inf2E
  3736     join1_iff               ~> sup1_iff
  3737     join2_iff               ~> sup2_iff
  3738     join1I1                 ~> sup1I1
  3739     join2I1                 ~> sup2I1
  3740     join1I1                 ~> sup1I1
  3741     join2I2                 ~> sup1I2
  3742     join1CI                 ~> sup1CI
  3743     join2CI                 ~> sup2CI
  3744     join1E                  ~> sup1E
  3745     join2E                  ~> sup2E
  3746 
  3747     is_meet_Meet            ~> is_meet_Inf
  3748     Meet_bool_def           ~> Inf_bool_def
  3749     Meet_fun_def            ~> Inf_fun_def
  3750     Meet_greatest           ~> Inf_greatest
  3751     Meet_lower              ~> Inf_lower
  3752     Meet_set_def            ~> Inf_set_def
  3753 
  3754     Sup_def                 ~> Sup_Inf
  3755     Sup_bool_eq             ~> Sup_bool_def
  3756     Sup_fun_eq              ~> Sup_fun_def
  3757     Sup_set_eq              ~> Sup_set_def
  3758 
  3759     listsp_meetI            ~> listsp_infI
  3760     listsp_meet_eq          ~> listsp_inf_eq
  3761 
  3762     meet_min                ~> inf_min
  3763     join_max                ~> sup_max
  3764 
  3765 * Added syntactic class "size"; overloaded constant "size" now has
  3766 type "'a::size ==> bool"
  3767 
  3768 * Internal reorganisation of `size' of datatypes: size theorems
  3769 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3770 simplification rules by default!); theorems "prod.size" now named
  3771 "*.size".
  3772 
  3773 * Class "div" now inherits from class "times" rather than "type".
  3774 INCOMPATIBILITY.
  3775 
  3776 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  3777 Linorder etc.  have disappeared; operations defined in terms of
  3778 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  3779 
  3780 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  3781 
  3782 * HOL-Word: New extensive library and type for generic, fixed size
  3783 machine words, with arithemtic, bit-wise, shifting and rotating
  3784 operations, reflection into int, nat, and bool lists, automation for
  3785 linear arithmetic (by automatic reflection into nat or int), including
  3786 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  3787 arithmetic type classes, supporting automatic simplification of
  3788 numerals on all operations.
  3789 
  3790 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  3791 
  3792 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  3793 
  3794 * Code generator library theories:
  3795   - Code_Integer represents HOL integers by big integer literals in target
  3796     languages.
  3797   - Code_Char represents HOL characters by character literals in target
  3798     languages.
  3799   - Code_Char_chr like Code_Char, but also offers treatment of character
  3800     codes; includes Code_Integer.
  3801   - Executable_Set allows to generate code for finite sets using lists.
  3802   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  3803     denominator).
  3804   - Executable_Real implements a subset of real numbers, namly those
  3805     representable by rational numbers.
  3806   - Efficient_Nat implements natural numbers by integers, which in general will
  3807     result in higher efficency; pattern matching with 0/Suc is eliminated;
  3808     includes Code_Integer.
  3809   - Code_Index provides an additional datatype index which is mapped to
  3810     target-language built-in integers.
  3811   - Code_Message provides an additional datatype message_string which is isomorphic to
  3812     strings; messages are mapped to target-language strings.
  3813 
  3814 * New package for inductive predicates
  3815 
  3816   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  3817 
  3818     inductive
  3819       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3820       for z_1 :: U_1 and ... and z_n :: U_m
  3821     where
  3822       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3823     | ...
  3824 
  3825   with full support for type-inference, rather than
  3826 
  3827     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3828 
  3829     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3830     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3831 
  3832     inductive "s z_1 ... z_m"
  3833     intros
  3834       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3835       ...
  3836 
  3837   For backward compatibility, there is a wrapper allowing inductive
  3838   sets to be defined with the new package via
  3839 
  3840     inductive_set
  3841       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3842       for z_1 :: U_1 and ... and z_n :: U_m
  3843     where
  3844       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3845     | ...
  3846 
  3847   or
  3848 
  3849     inductive_set
  3850       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3851       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3852       for z_1 :: U_1 and ... and z_n :: U_m
  3853     where
  3854       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3855     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3856     | ...
  3857 
  3858   if the additional syntax "p ..." is required.
  3859 
  3860   Numerous examples can be found in the subdirectories src/HOL/Auth,
  3861   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  3862 
  3863   INCOMPATIBILITIES:
  3864 
  3865   - Since declaration and definition of inductive sets or predicates
  3866     is no longer separated, abbreviations involving the newly
  3867     introduced sets or predicates must be specified together with the
  3868     introduction rules after the 'where' keyword (see above), rather
  3869     than before the actual inductive definition.
  3870 
  3871   - The variables in induction and elimination rules are now
  3872     quantified in the order of their occurrence in the introduction
  3873     rules, rather than in alphabetical order. Since this may break
  3874     some proofs, these proofs either have to be repaired, e.g. by
  3875     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  3876     statements of the form
  3877 
  3878       case (rule_i a_i_1 ... a_i_{k_i})
  3879 
  3880     or the old order of quantification has to be restored by explicitly adding
  3881     meta-level quantifiers in the introduction rules, i.e.
  3882 
  3883       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  3884 
  3885   - The format of the elimination rules is now
  3886 
  3887       p z_1 ... z_m x_1 ... x_n ==>
  3888         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3889         ==> ... ==> P
  3890 
  3891     for predicates and
  3892 
  3893       (x_1, ..., x_n) : s z_1 ... z_m ==>
  3894         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3895         ==> ... ==> P
  3896 
  3897     for sets rather than
  3898 
  3899       x : s z_1 ... z_m ==>
  3900         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  3901         ==> ... ==> P
  3902 
  3903     This may require terms in goals to be expanded to n-tuples
  3904     (e.g. using case_tac or simplification with the split_paired_all
  3905     rule) before the above elimination rule is applicable.
  3906 
  3907   - The elimination or case analysis rules for (mutually) inductive
  3908     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  3909     list of rules "p_1_..._p_k.elims" is no longer available.
  3910 
  3911 * New package "function"/"fun" for general recursive functions,
  3912 supporting mutual and nested recursion, definitions in local contexts,
  3913 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  3914 for small examples, and the separate tutorial on the function
  3915 package. The old recdef "package" is still available as before, but
  3916 users are encouraged to use the new package.
  3917 
  3918 * Method "lexicographic_order" automatically synthesizes termination
  3919 relations as lexicographic combinations of size measures. 
  3920 
  3921 * Case-expressions allow arbitrary constructor-patterns (including
  3922 "_") and take their order into account, like in functional
  3923 programming.  Internally, this is translated into nested
  3924 case-expressions; missing cases are added and mapped to the predefined
  3925 constant "undefined". In complicated cases printing may no longer show
  3926 the original input but the internal form. Lambda-abstractions allow
  3927 the same form of pattern matching: "% pat1 => e1 | ..." is an
  3928 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  3929 variable.
  3930 
  3931 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  3932 is an abbreviation for "of_nat :: nat => int". The simplification
  3933 rules for "of_nat" have been changed to work like "int" did
  3934 previously.  Potential INCOMPATIBILITY:
  3935   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  3936   - of_nat_diff and of_nat_mult are no longer default simp rules
  3937 
  3938 * Method "algebra" solves polynomial equations over (semi)rings using
  3939 Groebner bases. The (semi)ring structure is defined by locales and the
  3940 tool setup depends on that generic context. Installing the method for
  3941 a specific type involves instantiating the locale and possibly adding
  3942 declarations for computation on the coefficients.  The method is
  3943 already instantiated for natural numbers and for the axiomatic class
  3944 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  3945 CALCULEMUS 2007 for the general principles underlying this
  3946 architecture of context-aware proof-tools.
  3947 
  3948 * Method "ferrack" implements quantifier elimination over
  3949 special-purpose dense linear orders using locales (analogous to
  3950 "algebra"). The method is already installed for class
  3951 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  3952 rat, etc.
  3953 
  3954 * Former constant "List.op @" now named "List.append".  Use ML
  3955 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  3956 circumvent possible incompatibilities when working on ML level.
  3957 
  3958 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  3959 
  3960 * New function listsum :: 'a list => 'a for arbitrary monoids.
  3961 Special syntax: "SUM x <- xs. f x" (and latex variants)
  3962 
  3963 * New syntax for Haskell-like list comprehension (input only), eg.
  3964 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  3965 
  3966 * The special syntax for function "filter" has changed from [x :
  3967 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  3968 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  3969 
  3970 * [a..b] is now defined for arbitrary linear orders.  It used to be
  3971 defined on nat only, as an abbreviation for [a..<Suc b]
  3972 INCOMPATIBILITY.
  3973 
  3974 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  3975 
  3976 * New functions "sorted" and "sort" in src/HOL/List.thy.
  3977 
  3978 * New lemma collection field_simps (an extension of ring_simps) for
  3979 manipulating (in)equations involving division. Multiplies with all
  3980 denominators that can be proved to be non-zero (in equations) or
  3981 positive/negative (in inequations).
  3982 
  3983 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  3984 have been improved and renamed to ring_simps, group_simps and
  3985 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  3986 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  3987 
  3988 * Theory Library/Commutative_Ring: switched from recdef to function
  3989 package; constants add, mul, pow now curried.  Infix syntax for
  3990 algebraic operations.
  3991 
  3992 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  3993 INCOMPATIBILITY.
  3994 
  3995 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  3996 INCOMPATIBILITY.
  3997 
  3998 * HOL/records: generalised field-update to take a function on the
  3999 field rather than the new value: r(|A := x|) is translated to A_update
  4000 (K x) r The K-combinator that is internally used is called K_record.
  4001 INCOMPATIBILITY: Usage of the plain update functions has to be
  4002 adapted.
  4003  
  4004 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4005 * x = 0, which are required for a semiring.  Richer structures do not
  4006 inherit from semiring_0 anymore, because this property is a theorem
  4007 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4008 there is more to prove, but this is mostly trivial.
  4009 
  4010 * Class "recpower" is generalized to arbitrary monoids, not just
  4011 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4012 commutativity or semiring properties additionally.
  4013 
  4014 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4015 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4016 better use 'abbreviation'.
  4017 
  4018 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4019 
  4020 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4021 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4022 significant changes for setting up numeral syntax for types:
  4023   - New constants Numeral.pred and Numeral.succ instead
  4024       of former Numeral.bin_pred and Numeral.bin_succ.
  4025   - Use integer operations instead of bin_add, bin_mult and so on.
  4026   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4027   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4028 
  4029 See src/HOL/Integ/IntArith.thy for an example setup.
  4030 
  4031 * Command 'normal_form' computes the normal form of a term that may
  4032 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4033 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4034 heavy-duty computations because the functions are compiled to ML
  4035 first.  Correspondingly, a method "normalization" is provided.  See
  4036 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4037 
  4038 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4039 25 like -->); output depends on the "iff" print_mode, the default is
  4040 "A = B" (with priority 50).
  4041 
  4042 * Relations less (<) and less_eq (<=) are also available on type bool.
  4043 Modified syntax to disallow nesting without explicit parentheses,
  4044 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4045 INCOMPATIBILITY.
  4046 
  4047 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4048 
  4049 * Relation composition operator "op O" now has precedence 75 and binds
  4050 stronger than union and intersection. INCOMPATIBILITY.
  4051 
  4052 * The old set interval syntax "{m..n(}" (and relatives) has been
  4053 removed.  Use "{m..<n}" (and relatives) instead.
  4054 
  4055 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4056 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4057 ``declare [[simproc del: neq]]''.
  4058 
  4059 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4060 True/False.
  4061 
  4062 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4063 
  4064 * Theorem setsum_mult renamed to setsum_right_distrib.
  4065 
  4066 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4067 ``rule'' method.
  4068 
  4069 * Reimplemented methods "sat" and "satx", with several improvements:
  4070 goals no longer need to be stated as "<prems> ==> False", equivalences
  4071 (i.e. "=" on type bool) are handled, variable names of the form
  4072 "lit_<n>" are no longer reserved, significant speedup.
  4073 
  4074 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4075 zChaff is still supported as well.
  4076 
  4077 * 'inductive' and 'datatype': provide projections of mutual rules,
  4078 bundled as foo_bar.inducts;
  4079 
  4080 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4081 Library.
  4082 
  4083 * Library: moved theory Accessible_Part to main HOL.
  4084 
  4085 * Library: added theory Coinductive_List of potentially infinite lists
  4086 as greatest fixed-point.
  4087 
  4088 * Library: added theory AssocList which implements (finite) maps as
  4089 association lists.
  4090 
  4091 * Method "evaluation" solves goals (i.e. a boolean expression)
  4092 efficiently by compiling it to ML.  The goal is "proved" (via an
  4093 oracle) if it evaluates to True.
  4094 
  4095 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4096 also when invoked by the simplifier.  This results in the Simplifier
  4097 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4098 Configuration option fast_arith_split_limit=0 recovers the old
  4099 behavior.
  4100 
  4101 * Support for hex (0x20) and binary (0b1001) numerals.
  4102 
  4103 * New method: reify eqs (t), where eqs are equations for an
  4104 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4105 parameter, computes a term s::'b and a list xs::'a list and proves the
  4106 theorem I xs s = t. This is also known as reification or quoting. The
  4107 resulting theorem is applied to the subgoal to substitute t with I xs
  4108 s.  If t is omitted, the subgoal itself is reified.
  4109 
  4110 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4111 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4112 where f is supposed to be a computable function (in the sense of code
  4113 generattion). The method uses reify to compute s and xs as above then
  4114 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4115 r and finally gets the theorem t = r, which is again applied to the
  4116 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4117 
  4118 * Reflection: Automatic reification now handels binding, an example is
  4119 available in src/HOL/ex/ReflectionEx.thy
  4120 
  4121 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4122 command 'statespace' that is similar to 'record', but introduces an
  4123 abstract specification based on the locale infrastructure instead of
  4124 HOL types.  This leads to extra flexibility in composing state spaces,
  4125 in particular multiple inheritance and renaming of components.
  4126 
  4127 
  4128 *** HOL-Complex ***
  4129 
  4130 * Hyperreal: Functions root and sqrt are now defined on negative real
  4131 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4132 Nonnegativity side conditions have been removed from many lemmas, so
  4133 that more subgoals may now be solved by simplification; potential
  4134 INCOMPATIBILITY.
  4135 
  4136 * Real: new type classes formalize real normed vector spaces and
  4137 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4138 and norm :: 'a => real.
  4139 
  4140 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4141 reals into other types. The overloaded constant Reals :: 'a set is now
  4142 defined as range of_real; potential INCOMPATIBILITY.
  4143 
  4144 * Real: proper support for ML code generation, including 'quickcheck'.
  4145 Reals are implemented as arbitrary precision rationals.
  4146 
  4147 * Hyperreal: Several constants that previously worked only for the
  4148 reals have been generalized, so they now work over arbitrary vector
  4149 spaces. Type annotations may need to be added in some cases; potential
  4150 INCOMPATIBILITY.
  4151 
  4152   Infinitesimal  :: ('a::real_normed_vector) star set
  4153   HFinite        :: ('a::real_normed_vector) star set
  4154   HInfinite      :: ('a::real_normed_vector) star set
  4155   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4156   monad          :: ('a::real_normed_vector) star => 'a star set
  4157   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4158   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4159   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4160   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4161   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4162   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4163   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4164   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4165   sgn            :: 'a::real_normed_vector => 'a
  4166   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4167 
  4168 * Complex: Some complex-specific constants are now abbreviations for
  4169 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4170 hnorm.  Other constants have been entirely removed in favor of the
  4171 polymorphic versions (INCOMPATIBILITY):
  4172 
  4173   approx        <-- capprox
  4174   HFinite       <-- CFinite
  4175   HInfinite     <-- CInfinite
  4176   Infinitesimal <-- CInfinitesimal
  4177   monad         <-- cmonad
  4178   galaxy        <-- cgalaxy
  4179   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4180   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4181   (ns)deriv     <-- (ns)cderiv
  4182 
  4183 
  4184 *** HOL-Algebra ***
  4185 
  4186 * Formalisation of ideals and the quotient construction over rings.
  4187 
  4188 * Order and lattice theory no longer based on records.
  4189 INCOMPATIBILITY.
  4190 
  4191 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4192 greatest_closed.  INCOMPATIBILITY.
  4193 
  4194 * Method algebra is now set up via an attribute.  For examples see
  4195 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4196 of algebraic structures.
  4197 
  4198 * Renamed theory CRing to Ring.
  4199 
  4200 
  4201 *** HOL-Nominal ***
  4202 
  4203 * Substantial, yet incomplete support for nominal datatypes (binding
  4204 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4205 src/HOL/Nominal/Examples.  Prospective users should consult
  4206 http://isabelle.in.tum.de/nominal/
  4207 
  4208 
  4209 *** ML ***
  4210 
  4211 * ML basics: just one true type int, which coincides with IntInf.int
  4212 (even on SML/NJ).
  4213 
  4214 * ML within Isar: antiquotations allow to embed statically-checked
  4215 formal entities in the source, referring to the context available at
  4216 compile-time.  For example:
  4217 
  4218 ML {* @{sort "{zero,one}"} *}
  4219 ML {* @{typ "'a => 'b"} *}
  4220 ML {* @{term "%x. x"} *}
  4221 ML {* @{prop "x == y"} *}
  4222 ML {* @{ctyp "'a => 'b"} *}
  4223 ML {* @{cterm "%x. x"} *}
  4224 ML {* @{cprop "x == y"} *}
  4225 ML {* @{thm asm_rl} *}
  4226 ML {* @{thms asm_rl} *}
  4227 ML {* @{type_name c} *}
  4228 ML {* @{type_syntax c} *}
  4229 ML {* @{const_name c} *}
  4230 ML {* @{const_syntax c} *}
  4231 ML {* @{context} *}
  4232 ML {* @{theory} *}
  4233 ML {* @{theory Pure} *}
  4234 ML {* @{theory_ref} *}
  4235 ML {* @{theory_ref Pure} *}
  4236 ML {* @{simpset} *}
  4237 ML {* @{claset} *}
  4238 ML {* @{clasimpset} *}
  4239 
  4240 The same works for sources being ``used'' within an Isar context.
  4241 
  4242 * ML in Isar: improved error reporting; extra verbosity with
  4243 ML_Context.trace enabled.
  4244 
  4245 * Pure/General/table.ML: the join operations now works via exceptions
  4246 DUP/SAME instead of type option. This is simpler in simple cases, and
  4247 admits slightly more efficient complex applications.
  4248 
  4249 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4250 use Context.generic instead of just theory.
  4251 
  4252 * Pure: datatype Context.generic joins theory/Proof.context and
  4253 provides some facilities for code that works in either kind of
  4254 context, notably GenericDataFun for uniform theory and proof data.
  4255 
  4256 * Pure: simplified internal attribute type, which is now always
  4257 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4258 local (Proof.context) attributes have been discontinued, while
  4259 minimizing code duplication. Thm.rule_attribute and
  4260 Thm.declaration_attribute build canonical attributes; see also structure
  4261 Context for further operations on Context.generic, notably
  4262 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4263 declarations and definitions.
  4264 
  4265 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4266 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4267 init only required for impure data. INCOMPATIBILITY: empty really need
  4268 to be empty (no dependencies on theory content!)
  4269 
  4270 * Pure/kernel: consts certification ignores sort constraints given in
  4271 signature declarations. (This information is not relevant to the
  4272 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4273 potential INCOMPATIBILITY.
  4274 
  4275 * Pure: axiomatic type classes are now purely definitional, with
  4276 explicit proofs of class axioms and super class relations performed
  4277 internally. See Pure/axclass.ML for the main internal interfaces --
  4278 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4279 AxClass.axiomatize_class/classrel/arity supersede
  4280 Sign.add_classes/classrel/arities.
  4281 
  4282 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4283 global/local versions on theory vs. Proof.context have been
  4284 discontinued; Attrib.syntax and Method.syntax have been adapted
  4285 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4286 attributes, methods, etc.
  4287 
  4288 * Pure: several functions of signature "... -> theory -> theory * ..."
  4289 have been reoriented to "... -> theory -> ... * theory" in order to
  4290 allow natural usage in combination with the ||>, ||>>, |-> and
  4291 fold_map combinators.
  4292 
  4293 * Pure: official theorem names (closed derivations) and additional
  4294 comments (tags) are now strictly separate.  Name hints -- which are
  4295 maintained as tags -- may be attached any time without affecting the
  4296 derivation.
  4297 
  4298 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4299 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4300 achieve the old behaviour.
  4301 
  4302 * Pure: the "Goal" constant is now called "prop", supporting a
  4303 slightly more general idea of ``protecting'' meta-level rule
  4304 statements.
  4305 
  4306 * Pure: Logic.(un)varify only works in a global context, which is now
  4307 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4308 Logic.legacy_(un)varify as temporary workaround.
  4309 
  4310 * Pure: structure Name provides scalable operations for generating
  4311 internal variable names, notably Name.variants etc.  This replaces
  4312 some popular functions from term.ML:
  4313 
  4314   Term.variant		->  Name.variant
  4315   Term.variantlist	->  Name.variant_list
  4316   Term.invent_names	->  Name.invent_list
  4317 
  4318 Note that low-level renaming rarely occurs in new code -- operations
  4319 from structure Variable are used instead (see below).
  4320 
  4321 * Pure: structure Variable provides fundamental operations for proper
  4322 treatment of fixed/schematic variables in a context.  For example,
  4323 Variable.import introduces fixes for schematics of given facts and
  4324 Variable.export reverses the effect (up to renaming) -- this replaces
  4325 various freeze_thaw operations.
  4326 
  4327 * Pure: structure Goal provides simple interfaces for
  4328 init/conclude/finish and tactical prove operations (replacing former
  4329 Tactic.prove).  Goal.prove is the canonical way to prove results
  4330 within a given context; Goal.prove_global is a degraded version for
  4331 theory level goals, including a global Drule.standard.  Note that
  4332 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4333 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4334 in a locale context).
  4335 
  4336 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4337 and type checking (Syntax.check_term etc.), with common combinations
  4338 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4339 which are considered legacy and await removal.
  4340 
  4341 * Pure/Syntax: generic interfaces for type unchecking
  4342 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4343 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4344 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4345 available for convenience, but refer to the very same operations using
  4346 a mere theory instead of a full context.
  4347 
  4348 * Isar: simplified treatment of user-level errors, using exception
  4349 ERROR of string uniformly.  Function error now merely raises ERROR,
  4350 without any side effect on output channels.  The Isar toplevel takes
  4351 care of proper display of ERROR exceptions.  ML code may use plain
  4352 handle/can/try; cat_error may be used to concatenate errors like this:
  4353 
  4354   ... handle ERROR msg => cat_error msg "..."
  4355 
  4356 Toplevel ML code (run directly or through the Isar toplevel) may be
  4357 embedded into the Isar toplevel with exception display/debug like
  4358 this:
  4359 
  4360   Isar.toplevel (fn () => ...)
  4361 
  4362 INCOMPATIBILITY, removed special transform_error facilities, removed
  4363 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4364 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4365 -- use plain ERROR instead.
  4366 
  4367 * Isar: theory setup now has type (theory -> theory), instead of a
  4368 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4369 
  4370 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4371 ProofContext.debug/verbose flags.
  4372 
  4373 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4374 theory before entering a proof state.  Transactions now always see a
  4375 quasi-functional intermediate checkpoint, both in interactive and
  4376 batch mode.
  4377 
  4378 * Isar: simplified interfaces for outer syntax.  Renamed
  4379 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4380 OuterSyntax.add_parsers -- this functionality is now included in
  4381 OuterSyntax.command etc.  INCOMPATIBILITY.
  4382 
  4383 * Simplifier: the simpset of a running simplification process now
  4384 contains a proof context (cf. Simplifier.the_context), which is the
  4385 very context that the initial simpset has been retrieved from (by
  4386 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4387 (solver, looper etc.) may depend on arbitrary proof data.
  4388 
  4389 * Simplifier.inherit_context inherits the proof context (plus the
  4390 local bounds) of the current simplification process; any simproc
  4391 etc. that calls the Simplifier recursively should do this!  Removed
  4392 former Simplifier.inherit_bounds, which is already included here --
  4393 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4394 specify an explicit context using Simplifier.context/theory_context.
  4395 
  4396 * Simplifier/Classical Reasoner: more abstract interfaces
  4397 change_simpset/claset for modifying the simpset/claset reference of a
  4398 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4399 INCOMPATIBILITY.
  4400 
  4401 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4402 "Trueprop" etc.
  4403 
  4404 
  4405 *** System ***
  4406 
  4407 * settings: the default heap location within ISABELLE_HOME_USER now
  4408 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4409 Isabelle installations.
  4410 
  4411 * isabelle-process: option -S (secure mode) disables some critical
  4412 operations, notably runtime compilation and evaluation of ML source
  4413 code.
  4414 
  4415 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4416 
  4417 * Support for parallel execution, using native multicore support of
  4418 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4419 independent theories, according to the given theory header
  4420 specifications. The maximum number of worker threads is specified via
  4421 usedir option -M or the "max-threads" setting in Proof General. A
  4422 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4423 to 6 on a 8-core machine.  User-code needs to observe certain
  4424 guidelines for thread-safe programming, see appendix A in the Isar
  4425 Implementation manual.
  4426 
  4427 
  4428 
  4429 New in Isabelle2005 (October 2005)
  4430 ----------------------------------
  4431 
  4432 *** General ***
  4433 
  4434 * Theory headers: the new header syntax for Isar theories is
  4435 
  4436   theory <name>
  4437   imports <theory1> ... <theoryN>
  4438   uses <file1> ... <fileM>
  4439   begin
  4440 
  4441 where the 'uses' part is optional.  The previous syntax
  4442 
  4443   theory <name> = <theory1> + ... + <theoryN>:
  4444 
  4445 will disappear in the next release.  Use isatool fixheaders to convert
  4446 existing theory files.  Note that there is no change in ancient
  4447 non-Isar theories now, but these will disappear soon.
  4448 
  4449 * Theory loader: parent theories can now also be referred to via
  4450 relative and absolute paths.
  4451 
  4452 * Command 'find_theorems' searches for a list of criteria instead of a
  4453 list of constants. Known criteria are: intro, elim, dest, name:string,
  4454 simp:term, and any term. Criteria can be preceded by '-' to select
  4455 theorems that do not match. Intro, elim, dest select theorems that
  4456 match the current goal, name:s selects theorems whose fully qualified
  4457 name contain s, and simp:term selects all simplification rules whose
  4458 lhs match term.  Any other term is interpreted as pattern and selects
  4459 all theorems matching the pattern. Available in ProofGeneral under
  4460 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4461 
  4462   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4463 
  4464 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4465 matching the current goal as introduction rule and not having "HOL."
  4466 in their name (i.e. not being defined in theory HOL).
  4467 
  4468 * Command 'thms_containing' has been discontinued in favour of
  4469 'find_theorems'; INCOMPATIBILITY.
  4470 
  4471 * Communication with Proof General is now 8bit clean, which means that
  4472 Unicode text in UTF-8 encoding may be used within theory texts (both
  4473 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4474 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4475 
  4476   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4477   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4478 
  4479 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4480 Classical Reasoner.  Typical big applications run around 2 times
  4481 faster.
  4482 
  4483 
  4484 *** Document preparation ***
  4485 
  4486 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4487 of raw sources.  Only those symbols that do not require additional
  4488 LaTeX packages (depending on comments in isabellesym.sty) are
  4489 displayed properly, everything else is left verbatim.  isatool display
  4490 and isatool print are used as front ends (these are subject to the
  4491 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4492 
  4493 * Command tags control specific markup of certain regions of text,
  4494 notably folding and hiding.  Predefined tags include "theory" (for
  4495 theory begin and end), "proof" for proof commands, and "ML" for
  4496 commands involving ML code; the additional tags "visible" and
  4497 "invisible" are unused by default.  Users may give explicit tag
  4498 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4499 interpretation of tags is determined by the LaTeX job during document
  4500 preparation: see option -V of isatool usedir, or options -n and -t of
  4501 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4502 \isadroptag.
  4503 
  4504 Several document versions may be produced at the same time via isatool
  4505 usedir (the generated index.html will link all of them).  Typical
  4506 specifications include ''-V document=theory,proof,ML'' to present
  4507 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4508 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4509 these parts without any formal replacement text.  The Isabelle site
  4510 default settings produce ''document'' and ''outline'' versions as
  4511 specified above.
  4512 
  4513 * Several new antiquotations:
  4514 
  4515   @{term_type term} prints a term with its type annotated;
  4516 
  4517   @{typeof term} prints the type of a term;
  4518 
  4519   @{const const} is the same as @{term const}, but checks that the
  4520   argument is a known logical constant;
  4521 
  4522   @{term_style style term} and @{thm_style style thm} print a term or
  4523   theorem applying a "style" to it
  4524 
  4525   @{ML text}
  4526 
  4527 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4528 definitions, equations, inequations etc., 'concl' printing only the
  4529 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4530 to print the specified premise.  TermStyle.add_style provides an ML
  4531 interface for introducing further styles.  See also the "LaTeX Sugar"
  4532 document practical applications.  The ML antiquotation prints
  4533 type-checked ML expressions verbatim.
  4534 
  4535 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4536 and 'text' support optional locale specification '(in loc)', which
  4537 specifies the default context for interpreting antiquotations.  For
  4538 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4539 
  4540 * Option 'locale=NAME' of antiquotations specifies an alternative
  4541 context interpreting the subsequent argument.  For example: @{thm
  4542 [locale=lattice] inf_assoc}.
  4543 
  4544 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4545 a proof context.
  4546 
  4547 * Proper output of antiquotations for theory commands involving a
  4548 proof context (such as 'locale' or 'theorem (in loc) ...').
  4549 
  4550 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4551 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4552 
  4553 * isatool usedir: new option -C (default true) controls whether option
  4554 -D should include a copy of the original document directory; -C false
  4555 prevents unwanted effects such as copying of administrative CVS data.
  4556 
  4557 
  4558 *** Pure ***
  4559 
  4560 * Considerably improved version of 'constdefs' command.  Now performs
  4561 automatic type-inference of declared constants; additional support for
  4562 local structure declarations (cf. locales and HOL records), see also
  4563 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4564 sequential dependencies of definitions within a single 'constdefs'
  4565 section; moreover, the declared name needs to be an identifier.  If
  4566 all fails, consider to fall back on 'consts' and 'defs' separately.
  4567 
  4568 * Improved indexed syntax and implicit structures.  First of all,
  4569 indexed syntax provides a notational device for subscripted
  4570 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4571 expressions.  Secondly, in a local context with structure
  4572 declarations, number indexes \<^sub>n or the empty index (default
  4573 number 1) refer to a certain fixed variable implicitly; option
  4574 show_structs controls printing of implicit structures.  Typical
  4575 applications of these concepts involve record types and locales.
  4576 
  4577 * New command 'no_syntax' removes grammar declarations (and
  4578 translations) resulting from the given syntax specification, which is
  4579 interpreted in the same manner as for the 'syntax' command.
  4580 
  4581 * 'Advanced' translation functions (parse_translation etc.) may depend
  4582 on the signature of the theory context being presently used for
  4583 parsing/printing, see also isar-ref manual.
  4584 
  4585 * Improved 'oracle' command provides a type-safe interface to turn an
  4586 ML expression of type theory -> T -> term into a primitive rule of
  4587 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4588 is already included here); see also FOL/ex/IffExample.thy;
  4589 INCOMPATIBILITY.
  4590 
  4591 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4592 before); "cI" is no longer bound, use "c.intro" instead.
  4593 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4594 axclasses vs. locales.
  4595 
  4596 * Improved internal renaming of symbolic identifiers -- attach primes
  4597 instead of base 26 numbers.
  4598 
  4599 * New flag show_question_marks controls printing of leading question
  4600 marks in schematic variable names.
  4601 
  4602 * In schematic variable names, *any* symbol following \<^isub> or
  4603 \<^isup> is now treated as part of the base name.  For example, the
  4604 following works without printing of awkward ".0" indexes:
  4605 
  4606   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4607     by simp
  4608 
  4609 * Inner syntax includes (*(*nested*) comments*).
  4610 
  4611 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4612 annotations as "(00...)".
  4613 
  4614 * Clear separation of logical types and nonterminals, where the latter
  4615 may only occur in 'syntax' specifications or type abbreviations.
  4616 Before that distinction was only partially implemented via type class
  4617 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4618 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4619 exotic syntax specifications may require further adaption
  4620 (e.g. Cube/Cube.thy).
  4621 
  4622 * Removed obsolete type class "logic", use the top sort {} instead.
  4623 Note that non-logical types should be declared as 'nonterminals'
  4624 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4625 specifications.
  4626 
  4627 * Attributes 'induct' and 'cases': type or set names may now be
  4628 locally fixed variables as well.
  4629 
  4630 * Simplifier: can now control the depth to which conditional rewriting
  4631 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4632 Limit.
  4633 
  4634 * Simplifier: simplification procedures may now take the current
  4635 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4636 interface), which is very useful for calling the Simplifier
  4637 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4638 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4639 low-level mk_simproc no longer applies Logic.varify internally, to
  4640 allow for use in a context of fixed variables.
  4641 
  4642 * thin_tac now works even if the assumption being deleted contains !!
  4643 or ==>.  More generally, erule now works even if the major premise of
  4644 the elimination rule contains !! or ==>.
  4645 
  4646 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4647 
  4648 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4649 from Pure, which contains all common declarations already.  Both
  4650 theories are defined via plain Isabelle/Isar .thy files.
  4651 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4652 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4653 use isatool fixcpure to adapt your theory and ML sources.
  4654 
  4655 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4656 selections of theorems in named facts via index ranges.
  4657 
  4658 * 'print_theorems': in theory mode, really print the difference
  4659 wrt. the last state (works for interactive theory development only),
  4660 in proof mode print all local facts (cf. 'print_facts');
  4661 
  4662 * 'hide': option '(open)' hides only base names.
  4663 
  4664 * More efficient treatment of intermediate checkpoints in interactive
  4665 theory development.
  4666 
  4667 * Code generator is now invoked via code_module (incremental code
  4668 generation) and code_library (modular code generation, ML structures
  4669 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4670 must be quoted when used as identifiers.
  4671 
  4672 * New 'value' command for reading, evaluating and printing terms using
  4673 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4674 quoted when used as identifier.
  4675 
  4676 
  4677 *** Locales ***
  4678 
  4679 * New commands for the interpretation of locale expressions in
  4680 theories (1), locales (2) and proof contexts (3).  These generate
  4681 proof obligations from the expression specification.  After the
  4682 obligations have been discharged, theorems of the expression are added
  4683 to the theory, target locale or proof context.  The synopsis of the
  4684 commands is a follows:
  4685 
  4686   (1) interpretation expr inst
  4687   (2) interpretation target < expr
  4688   (3) interpret expr inst
  4689 
  4690 Interpretation in theories and proof contexts require a parameter
  4691 instantiation of terms from the current context.  This is applied to
  4692 specifications and theorems of the interpreted expression.
  4693 Interpretation in locales only permits parameter renaming through the
  4694 locale expression.  Interpretation is smart in that interpretations
  4695 that are active already do not occur in proof obligations, neither are
  4696 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4697 inspect active interpretations of a particular locale.  For details,
  4698 see the Isar Reference manual.  Examples can be found in
  4699 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4700 
  4701 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4702 'interpret' instead.
  4703 
  4704 * New context element 'constrains' for adding type constraints to
  4705 parameters.
  4706 
  4707 * Context expressions: renaming of parameters with syntax
  4708 redeclaration.
  4709 
  4710 * Locale declaration: 'includes' disallowed.
  4711 
  4712 * Proper static binding of attribute syntax -- i.e. types / terms /
  4713 facts mentioned as arguments are always those of the locale definition
  4714 context, independently of the context of later invocations.  Moreover,
  4715 locale operations (renaming and type / term instantiation) are applied
  4716 to attribute arguments as expected.
  4717 
  4718 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4719 actual attributes; rare situations may require Attrib.attribute to
  4720 embed those attributes into Attrib.src that lack concrete syntax.
  4721 Attribute implementations need to cooperate properly with the static
  4722 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4723 Attrib.XXX_thm etc. already do the right thing without further
  4724 intervention.  Only unusual applications -- such as "where" or "of"
  4725 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4726 on the context and the facts involved -- may have to assign parsed
  4727 values to argument tokens explicitly.
  4728 
  4729 * Changed parameter management in theorem generation for long goal
  4730 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4731 theorem statement in rare situations.
  4732 
  4733 * Locale inspection command 'print_locale' omits notes elements.  Use
  4734 'print_locale!' to have them included in the output.
  4735 
  4736 
  4737 *** Provers ***
  4738 
  4739 * Provers/hypsubst.ML: improved version of the subst method, for
  4740 single-step rewriting: it now works in bound variable contexts. New is
  4741 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4742 rewrite a different subterm than the original subst method, which is
  4743 still available as 'simplesubst'.
  4744 
  4745 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4746 and quasi orders.
  4747 
  4748 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4749 reflexive-transitive closure of relations.
  4750 
  4751 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4752 limit (previously hard-coded with a value of 20) user-definable.
  4753 
  4754 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4755 is peformed already.  Object-logics merely need to finish their
  4756 initial simpset configuration as before.  INCOMPATIBILITY.
  4757 
  4758 
  4759 *** HOL ***
  4760 
  4761 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4762 
  4763   syntax (epsilon)
  4764     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4765 
  4766 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4767 and x-symbol; use option '-m epsilon' to get it actually printed.
  4768 Moreover, the mathematically important symbolic identifier \<epsilon>
  4769 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4770 
  4771 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  4772 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  4773 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  4774 support corresponding Isar calculations.
  4775 
  4776 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  4777 instead of ":".
  4778 
  4779 * theory SetInterval: changed the syntax for open intervals:
  4780 
  4781   Old       New
  4782   {..n(}    {..<n}
  4783   {)n..}    {n<..}
  4784   {m..n(}   {m..<n}
  4785   {)m..n}   {m<..n}
  4786   {)m..n(}  {m<..<n}
  4787 
  4788 The old syntax is still supported but will disappear in the next
  4789 release.  For conversion use the following Emacs search and replace
  4790 patterns (these are not perfect but work quite well):
  4791 
  4792   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  4793   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  4794 
  4795 * Theory Commutative_Ring (in Library): method comm_ring for proving
  4796 equalities in commutative rings; method 'algebra' provides a generic
  4797 interface.
  4798 
  4799 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  4800 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  4801 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  4802 be a tuple pattern.
  4803 
  4804 Some new syntax forms are available:
  4805 
  4806   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  4807   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  4808   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  4809   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  4810 
  4811 The latter form "\<Sum>x < k. e" used to be based on a separate
  4812 function "Summation", which has been discontinued.
  4813 
  4814 * theory Finite_Set: in structured induction proofs, the insert case
  4815 is now 'case (insert x F)' instead of the old counterintuitive 'case
  4816 (insert F x)'.
  4817 
  4818 * The 'refute' command has been extended to support a much larger
  4819 fragment of HOL, including axiomatic type classes, constdefs and
  4820 typedefs, inductive datatypes and recursion.
  4821 
  4822 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  4823 Requires zChaff with proof generation to be installed.  See
  4824 HOL/ex/SAT_Examples.thy for examples.
  4825 
  4826 * Datatype induction via method 'induct' now preserves the name of the
  4827 induction variable. For example, when proving P(xs::'a list) by
  4828 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  4829 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  4830 in unstructured proof scripts.
  4831 
  4832 * Reworked implementation of records.  Improved scalability for
  4833 records with many fields, avoiding performance problems for type
  4834 inference. Records are no longer composed of nested field types, but
  4835 of nested extension types. Therefore the record type only grows linear
  4836 in the number of extensions and not in the number of fields.  The
  4837 top-level (users) view on records is preserved.  Potential
  4838 INCOMPATIBILITY only in strange cases, where the theory depends on the
  4839 old record representation. The type generated for a record is called
  4840 <record_name>_ext_type.
  4841 
  4842 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  4843 proofs triggered by a record definition or a simproc (if
  4844 quick_and_dirty is enabled).  Definitions of large records can take
  4845 quite long.
  4846 
  4847 New simproc record_upd_simproc for simplification of multiple record
  4848 updates enabled by default.  Moreover, trivial updates are also
  4849 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  4850 occasionally, since simplification is more powerful by default.
  4851 
  4852 * typedef: proper support for polymorphic sets, which contain extra
  4853 type-variables in the term.
  4854 
  4855 * Simplifier: automatically reasons about transitivity chains
  4856 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  4857 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  4858 old proofs break occasionally as simplification may now solve more
  4859 goals than previously.
  4860 
  4861 * Simplifier: converts x <= y into x = y if assumption y <= x is
  4862 present.  Works for all partial orders (class "order"), in particular
  4863 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  4864 just like y <= x.
  4865 
  4866 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  4867 bound variable or a constant then the let is unfolded.  Otherwise
  4868 first a is simplified to b, and then f b is simplified to g. If
  4869 possible we abstract b from g arriving at "let x = b in h x",
  4870 otherwise we unfold the let and arrive at g.  The simproc can be
  4871 enabled/disabled by the reference use_let_simproc.  Potential
  4872 INCOMPATIBILITY since simplification is more powerful by default.
  4873 
  4874 * Classical reasoning: the meson method now accepts theorems as arguments.
  4875 
  4876 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  4877 jobs to provide advice on the provability of subgoals.
  4878 
  4879 * Theory OrderedGroup and Ring_and_Field: various additions and
  4880 improvements to faciliate calculations involving equalities and
  4881 inequalities.
  4882 
  4883 The following theorems have been eliminated or modified
  4884 (INCOMPATIBILITY):
  4885 
  4886   abs_eq             now named abs_of_nonneg
  4887   abs_of_ge_0        now named abs_of_nonneg
  4888   abs_minus_eq       now named abs_of_nonpos
  4889   imp_abs_id         now named abs_of_nonneg
  4890   imp_abs_neg_id     now named abs_of_nonpos
  4891   mult_pos           now named mult_pos_pos
  4892   mult_pos_le        now named mult_nonneg_nonneg
  4893   mult_pos_neg_le    now named mult_nonneg_nonpos
  4894   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  4895   mult_neg           now named mult_neg_neg
  4896   mult_neg_le        now named mult_nonpos_nonpos
  4897 
  4898 * The following lemmas in Ring_and_Field have been added to the simplifier:
  4899      
  4900      zero_le_square
  4901      not_square_less_zero 
  4902 
  4903   The following lemmas have been deleted from Real/RealPow:
  4904   
  4905      realpow_zero_zero
  4906      realpow_two
  4907      realpow_less
  4908      zero_le_power
  4909      realpow_two_le
  4910      abs_realpow_two
  4911      realpow_two_abs     
  4912 
  4913 * Theory Parity: added rules for simplifying exponents.
  4914 
  4915 * Theory List:
  4916 
  4917 The following theorems have been eliminated or modified
  4918 (INCOMPATIBILITY):
  4919 
  4920   list_all_Nil       now named list_all.simps(1)
  4921   list_all_Cons      now named list_all.simps(2)
  4922   list_all_conv      now named list_all_iff
  4923   set_mem_eq         now named mem_iff
  4924 
  4925 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  4926 asymptotic "big O" calculations.  See the notes in BigO.thy.
  4927 
  4928 
  4929 *** HOL-Complex ***
  4930 
  4931 * Theory RealDef: better support for embedding natural numbers and
  4932 integers in the reals.
  4933 
  4934 The following theorems have been eliminated or modified
  4935 (INCOMPATIBILITY):
  4936 
  4937   exp_ge_add_one_self  now requires no hypotheses
  4938   real_of_int_add      reversed direction of equality (use [symmetric])
  4939   real_of_int_minus    reversed direction of equality (use [symmetric])
  4940   real_of_int_diff     reversed direction of equality (use [symmetric])
  4941   real_of_int_mult     reversed direction of equality (use [symmetric])
  4942 
  4943 * Theory RComplete: expanded support for floor and ceiling functions.
  4944 
  4945 * Theory Ln is new, with properties of the natural logarithm
  4946 
  4947 * Hyperreal: There is a new type constructor "star" for making
  4948 nonstandard types.  The old type names are now type synonyms:
  4949 
  4950   hypreal = real star
  4951   hypnat = nat star
  4952   hcomplex = complex star
  4953 
  4954 * Hyperreal: Many groups of similarly-defined constants have been
  4955 replaced by polymorphic versions (INCOMPATIBILITY):
  4956 
  4957   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  4958 
  4959   starset      <-- starsetNat, starsetC
  4960   *s*          <-- *sNat*, *sc*
  4961   starset_n    <-- starsetNat_n, starsetC_n
  4962   *sn*         <-- *sNatn*, *scn*
  4963   InternalSets <-- InternalNatSets, InternalCSets
  4964 
  4965   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  4966   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  4967   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  4968   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  4969   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  4970 
  4971 * Hyperreal: Many type-specific theorems have been removed in favor of
  4972 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  4973 
  4974   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  4975   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  4976   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  4977   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  4978   right_minus <-- hypreal_add_minus
  4979   left_minus <-- {hypreal,hcomplex}_add_minus_left
  4980   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  4981   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  4982   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  4983   mult_1_right <-- hcomplex_mult_one_right
  4984   mult_zero_left <-- hcomplex_mult_zero_left
  4985   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  4986   right_distrib <-- hypnat_add_mult_distrib2
  4987   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  4988   right_inverse <-- hypreal_mult_inverse
  4989   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  4990   order_refl <-- {hypreal,hypnat}_le_refl
  4991   order_trans <-- {hypreal,hypnat}_le_trans
  4992   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  4993   order_less_le <-- {hypreal,hypnat}_less_le
  4994   linorder_linear <-- {hypreal,hypnat}_le_linear
  4995   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  4996   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  4997   add_nonneg_nonneg <-- hypreal_le_add_order
  4998 
  4999 * Hyperreal: Separate theorems having to do with type-specific
  5000 versions of constants have been merged into theorems that apply to the
  5001 new polymorphic constants (INCOMPATIBILITY):
  5002 
  5003   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5004   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5005   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5006   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5007   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5008   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5009   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5010   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5011   STAR_diff <-- {STAR,STARC}_diff
  5012   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5013     STARC_hcomplex_of_complex}_image_subset
  5014   starset_n_Un <-- starset{Nat,C}_n_Un
  5015   starset_n_Int <-- starset{Nat,C}_n_Int
  5016   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5017   starset_n_diff <-- starset{Nat,C}_n_diff
  5018   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5019   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5020   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5021   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5022   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5023   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5024   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5025   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5026   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5027   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5028   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5029   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5030   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5031   starfun_diff <-- starfun{C,RC,CR}_diff
  5032   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5033   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5034   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5035   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5036   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5037   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5038   starfun_Id <-- starfunC_Id
  5039   starfun_approx <-- starfun{Nat,CR}_approx
  5040   starfun_capprox <-- starfun{C,RC}_capprox
  5041   starfun_abs <-- starfunNat_rabs
  5042   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5043   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5044   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5045   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5046   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5047   starfun_add_approx <-- starfunCR_add_approx
  5048   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5049   starfun_divide <-- starfun{C,CR,RC}_divide
  5050   starfun_n <-- starfun{Nat,C}_n
  5051   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5052   starfun_n_add <-- starfun{Nat,C}_n_add
  5053   starfun_n_add_minus <-- starfunNat_n_add_minus
  5054   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5055   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5056   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5057 
  5058   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5059   star_n_minus <-- {hypreal,hcomplex}_minus
  5060   star_n_diff <-- {hypreal,hcomplex}_diff
  5061   star_n_mult <-- {hypreal,hcomplex}_mult
  5062   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5063   star_n_le <-- {hypreal,hypnat}_le
  5064   star_n_less <-- {hypreal,hypnat}_less
  5065   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5066   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5067   star_n_abs <-- hypreal_hrabs
  5068   star_n_divide <-- hcomplex_divide
  5069 
  5070   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5071   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5072   star_of_diff <-- hypreal_of_real_diff
  5073   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5074   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5075   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5076   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5077   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5078   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5079   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5080   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5081   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5082   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5083   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5084   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5085   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5086   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5087   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5088   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5089   star_of_power <-- hypreal_of_real_power
  5090   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5091 
  5092 * Hyperreal: new method "transfer" that implements the transfer
  5093 principle of nonstandard analysis. With a subgoal that mentions
  5094 nonstandard types like "'a star", the command "apply transfer"
  5095 replaces it with an equivalent one that mentions only standard types.
  5096 To be successful, all free variables must have standard types; non-
  5097 standard variables must have explicit universal quantifiers.
  5098 
  5099 * Hyperreal: A theory of Taylor series.
  5100 
  5101 
  5102 *** HOLCF ***
  5103 
  5104 * Discontinued special version of 'constdefs' (which used to support
  5105 continuous functions) in favor of the general Pure one with full
  5106 type-inference.
  5107 
  5108 * New simplification procedure for solving continuity conditions; it
  5109 is much faster on terms with many nested lambda abstractions (cubic
  5110 instead of exponential time).
  5111 
  5112 * New syntax for domain package: selector names are now optional.
  5113 Parentheses should be omitted unless argument is lazy, for example:
  5114 
  5115   domain 'a stream = cons "'a" (lazy "'a stream")
  5116 
  5117 * New command 'fixrec' for defining recursive functions with pattern
  5118 matching; defining multiple functions with mutual recursion is also
  5119 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5120 sinr, or any data constructor defined by the domain package. The given
  5121 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5122 syntax and examples.
  5123 
  5124 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5125 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5126 but the proof obligation additionally includes an admissibility
  5127 requirement. The packages generate instances of class cpo or pcpo,
  5128 with continuity and strictness theorems for Rep and Abs.
  5129 
  5130 * HOLCF: Many theorems have been renamed according to a more standard naming
  5131 scheme (INCOMPATIBILITY):
  5132 
  5133   foo_inject:  "foo$x = foo$y ==> x = y"
  5134   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5135   foo_less:    "(foo$x << foo$y) = (x << y)"
  5136   foo_strict:  "foo$UU = UU"
  5137   foo_defined: "... ==> foo$x ~= UU"
  5138   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5139 
  5140 
  5141 *** ZF ***
  5142 
  5143 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5144 including the First Isomorphism Theorem (on quotienting by the kernel
  5145 of a homomorphism).
  5146 
  5147 * ZF/Simplifier: install second copy of type solver that actually
  5148 makes use of TC rules declared to Isar proof contexts (or locales);
  5149 the old version is still required for ML proof scripts.
  5150 
  5151 
  5152 *** Cube ***
  5153 
  5154 * Converted to Isar theory format; use locales instead of axiomatic
  5155 theories.
  5156 
  5157 
  5158 *** ML ***
  5159 
  5160 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5161 for ||>, ||>>, |>>,
  5162 
  5163 * Pure/library.ML no longer defines its own option datatype, but uses
  5164 that of the SML basis, which has constructors NONE and SOME instead of
  5165 None and Some, as well as exception Option.Option instead of OPTION.
  5166 The functions the, if_none, is_some, is_none have been adapted
  5167 accordingly, while Option.map replaces apsome.
  5168 
  5169 * Pure/library.ML: the exception LIST has been given up in favour of
  5170 the standard exceptions Empty and Subscript, as well as
  5171 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5172 superceded by the standard hd and tl functions etc.
  5173 
  5174 A number of basic list functions are no longer exported to the ML
  5175 toplevel, as they are variants of predefined functions.  The following
  5176 suggests how one can translate existing code:
  5177 
  5178     rev_append xs ys = List.revAppend (xs, ys)
  5179     nth_elem (i, xs) = List.nth (xs, i)
  5180     last_elem xs = List.last xs
  5181     flat xss = List.concat xss
  5182     seq fs = List.app fs
  5183     partition P xs = List.partition P xs
  5184     mapfilter f xs = List.mapPartial f xs
  5185 
  5186 * Pure/library.ML: several combinators for linear functional
  5187 transformations, notably reverse application and composition:
  5188 
  5189   x |> f                f #> g
  5190   (x, y) |-> f          f #-> g
  5191 
  5192 * Pure/library.ML: introduced/changed precedence of infix operators:
  5193 
  5194   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5195   infix 2 ?;
  5196   infix 3 o oo ooo oooo;
  5197   infix 4 ~~ upto downto;
  5198 
  5199 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5200 infix operators.
  5201 
  5202 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5203 fold_map support linear functional transformations and nesting.  For
  5204 example:
  5205 
  5206   fold f [x1, ..., xN] y =
  5207     y |> f x1 |> ... |> f xN
  5208 
  5209   (fold o fold) f [xs1, ..., xsN] y =
  5210     y |> fold f xs1 |> ... |> fold f xsN
  5211 
  5212   fold f [x1, ..., xN] =
  5213     f x1 #> ... #> f xN
  5214 
  5215   (fold o fold) f [xs1, ..., xsN] =
  5216     fold f xs1 #> ... #> fold f xsN
  5217 
  5218 * Pure/library.ML: the following selectors on type 'a option are
  5219 available:
  5220 
  5221   the:               'a option -> 'a  (*partial*)
  5222   these:             'a option -> 'a  where 'a = 'b list
  5223   the_default: 'a -> 'a option -> 'a
  5224   the_list:          'a option -> 'a list
  5225 
  5226 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5227 basic operations for association lists, following natural argument
  5228 order; moreover the explicit equality predicate passed here avoids
  5229 potentially expensive polymorphic runtime equality checks.
  5230 The old functions may be expressed as follows:
  5231 
  5232   assoc = uncurry (AList.lookup (op =))
  5233   assocs = these oo AList.lookup (op =)
  5234   overwrite = uncurry (AList.update (op =)) o swap
  5235 
  5236 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5237 
  5238   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5239   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5240 
  5241 replacing make_keylist and keyfilter (occassionally used)
  5242 Naive rewrites:
  5243 
  5244   make_keylist = AList.make
  5245   keyfilter = AList.find (op =)
  5246 
  5247 * eq_fst and eq_snd now take explicit equality parameter, thus
  5248   avoiding eqtypes. Naive rewrites:
  5249 
  5250     eq_fst = eq_fst (op =)
  5251     eq_snd = eq_snd (op =)
  5252 
  5253 * Removed deprecated apl and apr (rarely used).
  5254   Naive rewrites:
  5255 
  5256     apl (n, op) =>>= curry op n
  5257     apr (op, m) =>>= fn n => op (n, m)
  5258 
  5259 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5260 provides a reasonably efficient light-weight implementation of sets as
  5261 lists.
  5262 
  5263 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5264 few new operations; existing lookup and update are now curried to
  5265 follow natural argument order (for use with fold etc.);
  5266 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5267 
  5268 * Pure/General: output via the Isabelle channels of
  5269 writeln/warning/error etc. is now passed through Output.output, with a
  5270 hook for arbitrary transformations depending on the print_mode
  5271 (cf. Output.add_mode -- the first active mode that provides a output
  5272 function wins).  Already formatted output may be embedded into further
  5273 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5274 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5275 accommodate easy composition of diagnostic messages etc.  Programmers
  5276 rarely need to care about Output.output or Output.raw at all, with
  5277 some notable exceptions: Output.output is required when bypassing the
  5278 standard channels (writeln etc.), or in token translations to produce
  5279 properly formatted results; Output.raw is required when capturing
  5280 already output material that will eventually be presented to the user
  5281 a second time.  For the default print mode, both Output.output and
  5282 Output.raw have no effect.
  5283 
  5284 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5285 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5286 cumulative results are displayed at the end of a batch session.
  5287 
  5288 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5289 replaced by File.platform_path and File.shell_path (with appropriate
  5290 hooks).  This provides a clean interface for unusual systems where the
  5291 internal and external process view of file names are different.
  5292 
  5293 * Pure: more efficient orders for basic syntactic entities: added
  5294 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5295 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5296 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5297 orders now -- potential INCOMPATIBILITY for code that depends on a
  5298 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5299 Library.sort_strings on result).
  5300 
  5301 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5302 fold_types traverse types/terms from left to right, observing natural
  5303 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5304 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5305 
  5306 * Pure: name spaces have been refined, with significant changes of the
  5307 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5308 to extern(_table).  The plain name entry path is superceded by a
  5309 general 'naming' context, which also includes the 'policy' to produce
  5310 a fully qualified name and external accesses of a fully qualified
  5311 name; NameSpace.extend is superceded by context dependent
  5312 Sign.declare_name.  Several theory and proof context operations modify
  5313 the naming context.  Especially note Theory.restore_naming and
  5314 ProofContext.restore_naming to get back to a sane state; note that
  5315 Theory.add_path is no longer sufficient to recover from
  5316 Theory.absolute_path in particular.
  5317 
  5318 * Pure: new flags short_names (default false) and unique_names
  5319 (default true) for controlling output of qualified names.  If
  5320 short_names is set, names are printed unqualified.  If unique_names is
  5321 reset, the name prefix is reduced to the minimum required to achieve
  5322 the original result when interning again, even if there is an overlap
  5323 with earlier declarations.
  5324 
  5325 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5326 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5327 (useful for printing error messages).  INCOMPATIBILITY.
  5328 
  5329 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5330 Theory.theory are now identified, referring to the universal
  5331 Context.theory (see Pure/context.ML).  Actual signature and theory
  5332 content is managed as theory data.  The old code and interfaces were
  5333 spread over many files and structures; the new arrangement introduces
  5334 considerable INCOMPATIBILITY to gain more clarity:
  5335 
  5336   Context -- theory management operations (name, identity, inclusion,
  5337     parents, ancestors, merge, etc.), plus generic theory data;
  5338 
  5339   Sign -- logical signature and syntax operations (declaring consts,
  5340     types, etc.), plus certify/read for common entities;
  5341 
  5342   Theory -- logical theory operations (stating axioms, definitions,
  5343     oracles), plus a copy of logical signature operations (consts,
  5344     types, etc.); also a few basic management operations (Theory.copy,
  5345     Theory.merge, etc.)
  5346 
  5347 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5348 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5349 for convenience -- they merely return the theory.
  5350 
  5351 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5352 
  5353 * Pure: the Isar proof context type is already defined early in Pure
  5354 as Context.proof (note that ProofContext.context and Proof.context are
  5355 aliases, where the latter is the preferred name).  This enables other
  5356 Isabelle components to refer to that type even before Isar is present.
  5357 
  5358 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5359 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5360 any of these kinds.  For example, Sign.intern typeK is now
  5361 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5362 Theory.hide_types.  Also note that former
  5363 Theory.hide_classes/types/consts are now
  5364 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5365 internalize their arguments!  INCOMPATIBILITY.
  5366 
  5367 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5368 datatype thmref (with constructors Name and NameSelection) instead of
  5369 plain string -- INCOMPATIBILITY;
  5370 
  5371 * Pure: cases produced by proof methods specify options, where NONE
  5372 means to remove case bindings -- INCOMPATIBILITY in
  5373 (RAW_)METHOD_CASES.
  5374 
  5375 * Pure: the following operations retrieve axioms or theorems from a
  5376 theory node or theory hierarchy, respectively:
  5377 
  5378   Theory.axioms_of: theory -> (string * term) list
  5379   Theory.all_axioms_of: theory -> (string * term) list
  5380   PureThy.thms_of: theory -> (string * thm) list
  5381   PureThy.all_thms_of: theory -> (string * thm) list
  5382 
  5383 * Pure: print_tac now outputs the goal through the trace channel.
  5384 
  5385 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5386 Reference Toplevel.debug (default false) controls detailed printing
  5387 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5388 controls execution profiling -- set to 1 for time and 2 for space
  5389 (both increase the runtime).
  5390 
  5391 * Isar session: The initial use of ROOT.ML is now always timed,
  5392 i.e. the log will show the actual process times, in contrast to the
  5393 elapsed wall-clock time that the outer shell wrapper produces.
  5394 
  5395 * Simplifier: improved handling of bound variables (nameless
  5396 representation, avoid allocating new strings).  Simprocs that invoke
  5397 the Simplifier recursively should use Simplifier.inherit_bounds to
  5398 avoid local name clashes.  Failure to do so produces warnings
  5399 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5400 for further details.
  5401 
  5402 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5403 bindings for all theorems stored within a given theory; this may help
  5404 in porting non-Isar theories to Isar ones, while keeping ML proof
  5405 scripts for the time being.
  5406 
  5407 * ML operator HTML.with_charset specifies the charset begin used for
  5408 generated HTML files.  For example:
  5409 
  5410   HTML.with_charset "utf-8" use_thy "Hebrew";
  5411   HTML.with_charset "utf-8" use_thy "Chinese";
  5412 
  5413 
  5414 *** System ***
  5415 
  5416 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5417 isabelle, isatool etc.).
  5418 
  5419 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5420 isatool doc, isatool mkdir, display_drafts etc.).
  5421 
  5422 * isatool usedir: option -f allows specification of the ML file to be
  5423 used by Isabelle; default is ROOT.ML.
  5424 
  5425 * New isatool version outputs the version identifier of the Isabelle
  5426 distribution being used.
  5427 
  5428 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5429 (containing Boolean satisfiability problems) into Isabelle/HOL
  5430 theories.
  5431 
  5432 
  5433 
  5434 New in Isabelle2004 (April 2004)
  5435 --------------------------------
  5436 
  5437 *** General ***
  5438 
  5439 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5440   Replaces linorder.ML.
  5441 
  5442 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5443   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5444   (\<a>...\<z>), are now considered normal letters, and can therefore
  5445   be used anywhere where an ASCII letter (a...zA...Z) has until
  5446   now. COMPATIBILITY: This obviously changes the parsing of some
  5447   terms, especially where a symbol has been used as a binder, say
  5448   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5449   as an identifier.  Fix it by inserting a space around former
  5450   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5451   existing theory and ML files.
  5452 
  5453 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5454 
  5455 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5456   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5457   a normal (but invisible) letter. For multiple letter subscripts repeat
  5458   \<^isub> like this: x\<^isub>1\<^isub>2.
  5459 
  5460 * Pure: There are now sub-/superscripts that can span more than one
  5461   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5462   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5463   superscript. The new control characters are not identifier parts.
  5464 
  5465 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5466   content of "..." to the latex file instead of \isacntrl... . The "..."
  5467   may consist of any printable characters excluding the end bracket >.
  5468 
  5469 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5470   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5471   declare constants "final", which prevents their being given a definition
  5472   later.  It is useful for constants whose behaviour is fixed axiomatically
  5473   rather than definitionally, such as the meta-logic connectives.
  5474 
  5475 * Pure: 'instance' now handles general arities with general sorts
  5476   (i.e. intersections of classes),
  5477 
  5478 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5479   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5480   It can be changed to alter the colors/layout of generated pages.
  5481 
  5482 
  5483 *** Isar ***
  5484 
  5485 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5486   cut_tac, subgoal_tac and thin_tac:
  5487   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5488     locales are no longer forced to write Isar proof scripts.
  5489     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5490     emulations.
  5491   - INCOMPATIBILITY: names of variables to be instantiated may no
  5492     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5493     This is consistent with the instantiation attribute "where".
  5494 
  5495 * Attributes "where" and "of":
  5496   - Now take type variables of instantiated theorem into account when reading
  5497     the instantiation string.  This fixes a bug that caused instantiated
  5498     theorems to have too special types in some circumstances.
  5499   - "where" permits explicit instantiations of type variables.
  5500 
  5501 * Calculation commands "moreover" and "also" no longer interfere with
  5502   current facts ("this"), admitting arbitrary combinations with "then"
  5503   and derived forms.
  5504 
  5505 * Locales:
  5506   - Goal statements involving the context element "includes" no longer
  5507     generate theorems with internal delta predicates (those ending on
  5508     "_axioms") in the premise.
  5509     Resolve particular premise with <locale>.intro to obtain old form.
  5510   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5511     specification and "includes" elements in goal statement.
  5512   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5513     [intro?] and [elim?] (respectively) by default.
  5514   - Experimental command for instantiation of locales in proof contexts:
  5515         instantiate <label>[<attrs>]: <loc>
  5516     Instantiates locale <loc> and adds all its theorems to the current context
  5517     taking into account their attributes.  Label and attrs are optional
  5518     modifiers, like in theorem declarations.  If present, names of
  5519     instantiated theorems are qualified with <label>, and the attributes
  5520     <attrs> are applied after any attributes these theorems might have already.
  5521       If the locale has assumptions, a chained fact of the form
  5522     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5523     are derived.  The command does not support old-style locales declared
  5524     with "locale (open)".
  5525       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5526 
  5527 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5528   (Isar) contexts.
  5529 
  5530 
  5531 *** HOL ***
  5532 
  5533 * Proof import: new image HOL4 contains the imported library from
  5534   the HOL4 system with about 2500 theorems. It is imported by
  5535   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5536   can be used like any other Isabelle image.  See
  5537   HOL/Import/HOL/README for more information.
  5538 
  5539 * Simplifier:
  5540   - Much improved handling of linear and partial orders.
  5541     Reasoners for linear and partial orders are set up for type classes
  5542     "linorder" and "order" respectively, and are added to the default simpset
  5543     as solvers.  This means that the simplifier can build transitivity chains
  5544     to solve goals from the assumptions.
  5545   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5546     of blast or auto after simplification become unnecessary because the goal
  5547     is solved by simplification already.
  5548 
  5549 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5550     all proved in axiomatic type classes for semirings, rings and fields.
  5551 
  5552 * Numerics:
  5553   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5554     now formalized using the Ring_and_Field theory mentioned above.
  5555   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5556     than before, because now they are set up once in a generic manner.
  5557   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5558     Look for the general versions in Ring_and_Field (and Power if they concern
  5559     exponentiation).
  5560 
  5561 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5562 
  5563 * Records:
  5564   - Record types are now by default printed with their type abbreviation
  5565     instead of the list of all field types. This can be configured via
  5566     the reference "print_record_type_abbr".
  5567   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5568     (not enabled by default).
  5569   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5570     EX x. x = sel r to True (not enabled by default).
  5571   - Tactic "record_split_simp_tac" to split and simplify records added.
  5572 
  5573 * 'specification' command added, allowing for definition by
  5574   specification.  There is also an 'ax_specification' command that
  5575   introduces the new constants axiomatically.
  5576 
  5577 * arith(_tac) is now able to generate counterexamples for reals as well.
  5578 
  5579 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5580 
  5581 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5582   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5583 
  5584 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5585   matrix theory to linear programming.
  5586 
  5587 * Unions and Intersections:
  5588   The latex output syntax of UN and INT has been changed
  5589   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5590   i.e. the index formulae has become a subscript.
  5591   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5592 
  5593 * Unions and Intersections over Intervals:
  5594   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5595   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5596   like in normal math, and corresponding versions for < and for intersection.
  5597 
  5598 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5599   lexicographic dictonary ordering has been added as "lexord".
  5600 
  5601 * ML: the legacy theory structures Int and List have been removed. They had
  5602   conflicted with ML Basis Library structures having the same names.
  5603 
  5604 * 'refute' command added to search for (finite) countermodels.  Only works
  5605   for a fragment of HOL.  The installation of an external SAT solver is
  5606   highly recommended.  See "HOL/Refute.thy" for details.
  5607 
  5608 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5609   formulae under an assignment of free variables to random values.
  5610   In contrast to 'refute', it can deal with inductive datatypes,
  5611   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5612   for examples.
  5613 
  5614 
  5615 *** HOLCF ***
  5616 
  5617 * Streams now come with concatenation and are part of the HOLCF image
  5618 
  5619 
  5620 
  5621 New in Isabelle2003 (May 2003)
  5622 ------------------------------
  5623 
  5624 *** General ***
  5625 
  5626 * Provers/simplifier:
  5627 
  5628   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5629     Assumptions are now subject to complete mutual simplification,
  5630     not just from left to right. The simplifier now preserves
  5631     the order of assumptions.
  5632 
  5633     Potential INCOMPATIBILITY:
  5634 
  5635     -- simp sometimes diverges where the old version did
  5636        not, e.g. invoking simp on the goal
  5637 
  5638         [| P (f x); y = x; f x = f y |] ==> Q
  5639 
  5640        now gives rise to the infinite reduction sequence
  5641 
  5642         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5643 
  5644        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5645        kind of problem.
  5646 
  5647     -- Tactics combining classical reasoner and simplification (such as auto)
  5648        are also affected by this change, because many of them rely on
  5649        simp. They may sometimes diverge as well or yield a different numbers
  5650        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5651        in case of problems. Sometimes subsequent calls to the classical
  5652        reasoner will fail because a preceeding call to the simplifier too
  5653        eagerly simplified the goal, e.g. deleted redundant premises.
  5654 
  5655   - The simplifier trace now shows the names of the applied rewrite rules
  5656 
  5657   - You can limit the number of recursive invocations of the simplifier
  5658     during conditional rewriting (where the simplifie tries to solve the
  5659     conditions before applying the rewrite rule):
  5660     ML "simp_depth_limit := n"
  5661     where n is an integer. Thus you can force termination where previously
  5662     the simplifier would diverge.
  5663 
  5664   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5665 
  5666   - No longer aborts on failed congruence proof.  Instead, the
  5667     congruence is ignored.
  5668 
  5669 * Pure: New generic framework for extracting programs from constructive
  5670   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5671   as HOL/Extraction for some case studies.
  5672 
  5673 * Pure: The main goal of the proof state is no longer shown by default, only
  5674 the subgoals. This behaviour is controlled by a new flag.
  5675    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5676 (ML: Proof.show_main_goal).
  5677 
  5678 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5679 rules whose conclusion matches subgoal 1:
  5680       PG menu: Isabelle/Isar -> Show me -> matching rules
  5681 The rules are ordered by how closely they match the subgoal.
  5682 In particular, rules that solve a subgoal outright are displayed first
  5683 (or rather last, the way they are printed).
  5684 (ML: ProofGeneral.print_intros())
  5685 
  5686 * Pure: New flag trace_unify_fail causes unification to print
  5687 diagnostic information (PG: in trace buffer) when it fails. This is
  5688 useful for figuring out why single step proofs like rule, erule or
  5689 assumption failed.
  5690 
  5691 * Pure: Locale specifications now produce predicate definitions
  5692 according to the body of text (covering assumptions modulo local
  5693 definitions); predicate "loc_axioms" covers newly introduced text,
  5694 while "loc" is cumulative wrt. all included locale expressions; the
  5695 latter view is presented only on export into the global theory
  5696 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5697 on the old view without predicates;
  5698 
  5699 * Pure: predefined locales "var" and "struct" are useful for sharing
  5700 parameters (as in CASL, for example); just specify something like
  5701 ``var x + var y + struct M'' as import;
  5702 
  5703 * Pure: improved thms_containing: proper indexing of facts instead of
  5704 raw theorems; check validity of results wrt. current name space;
  5705 include local facts of proof configuration (also covers active
  5706 locales), cover fixed variables in index; may use "_" in term
  5707 specification; an optional limit for the number of printed facts may
  5708 be given (the default is 40);
  5709 
  5710 * Pure: disallow duplicate fact bindings within new-style theory files
  5711 (batch-mode only);
  5712 
  5713 * Provers: improved induct method: assumptions introduced by case
  5714 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5715 the goal statement); "foo" still refers to all facts collectively;
  5716 
  5717 * Provers: the function blast.overloaded has been removed: all constants
  5718 are regarded as potentially overloaded, which improves robustness in exchange
  5719 for slight decrease in efficiency;
  5720 
  5721 * Provers/linorder: New generic prover for transitivity reasoning over
  5722 linear orders.  Note: this prover is not efficient!
  5723 
  5724 * Isar: preview of problems to finish 'show' now produce an error
  5725 rather than just a warning (in interactive mode);
  5726 
  5727 
  5728 *** HOL ***
  5729 
  5730 * arith(_tac)
  5731 
  5732  - Produces a counter example if it cannot prove a goal.
  5733    Note that the counter example may be spurious if the goal is not a formula
  5734    of quantifier-free linear arithmetic.
  5735    In ProofGeneral the counter example appears in the trace buffer.
  5736 
  5737  - Knows about div k and mod k where k is a numeral of type nat or int.
  5738 
  5739  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5740    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5741    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5742 
  5743 * simp's arithmetic capabilities have been enhanced a bit: it now
  5744 takes ~= in premises into account (by performing a case split);
  5745 
  5746 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5747 are distributed over a sum of terms;
  5748 
  5749 * New tactic "trans_tac" and method "trans" instantiate
  5750 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5751 "<=", "<" and "=").
  5752 
  5753 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5754 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5755 
  5756 * 'typedef' command has new option "open" to suppress the set
  5757 definition;
  5758 
  5759 * functions Min and Max on finite sets have been introduced (theory
  5760 Finite_Set);
  5761 
  5762 * attribute [symmetric] now works for relations as well; it turns
  5763 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5764 
  5765 * induct over a !!-quantified statement (say !!x1..xn):
  5766   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5767 
  5768 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5769 %x. None. Warning: empty_def now refers to the previously hidden definition
  5770 of the empty set.
  5771 
  5772 * Algebra: formalization of classical algebra.  Intended as base for
  5773 any algebraic development in Isabelle.  Currently covers group theory
  5774 (up to Sylow's theorem) and ring theory (Universal Property of
  5775 Univariate Polynomials).  Contributions welcome;
  5776 
  5777 * GroupTheory: deleted, since its material has been moved to Algebra;
  5778 
  5779 * Complex: new directory of the complex numbers with numeric constants,
  5780 nonstandard complex numbers, and some complex analysis, standard and
  5781 nonstandard (Jacques Fleuriot);
  5782 
  5783 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  5784 
  5785 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  5786 Fleuriot);
  5787 
  5788 * Real/HahnBanach: updated and adapted to locales;
  5789 
  5790 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  5791 Gray and Kramer);
  5792 
  5793 * UNITY: added the Meier-Sanders theory of progress sets;
  5794 
  5795 * MicroJava: bytecode verifier and lightweight bytecode verifier
  5796 as abstract algorithms, instantiated to the JVM;
  5797 
  5798 * Bali: Java source language formalization. Type system, operational
  5799 semantics, axiomatic semantics. Supported language features:
  5800 classes, interfaces, objects,virtual methods, static methods,
  5801 static/instance fields, arrays, access modifiers, definite
  5802 assignment, exceptions.
  5803 
  5804 
  5805 *** ZF ***
  5806 
  5807 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  5808 universe, etc.);
  5809 
  5810 * Main ZF: virtually all theories converted to new-style format;
  5811 
  5812 
  5813 *** ML ***
  5814 
  5815 * Pure: Tactic.prove provides sane interface for internal proofs;
  5816 omits the infamous "standard" operation, so this is more appropriate
  5817 than prove_goalw_cterm in many situations (e.g. in simprocs);
  5818 
  5819 * Pure: improved error reporting of simprocs;
  5820 
  5821 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  5822 up simprocs;
  5823 
  5824 
  5825 *** Document preparation ***
  5826 
  5827 * uses \par instead of \\ for line breaks in theory text. This may
  5828 shift some page breaks in large documents. To get the old behaviour
  5829 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  5830 
  5831 * minimized dependencies of isabelle.sty and isabellesym.sty on
  5832 other packages
  5833 
  5834 * \<euro> now needs package babel/greek instead of marvosym (which
  5835 broke \Rightarrow)
  5836 
  5837 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  5838 textcomp package)
  5839 
  5840 
  5841 
  5842 New in Isabelle2002 (March 2002)
  5843 --------------------------------
  5844 
  5845 *** Document preparation ***
  5846 
  5847 * greatly simplified document preparation setup, including more
  5848 graceful interpretation of isatool usedir -i/-d/-D options, and more
  5849 instructive isatool mkdir; users should basically be able to get
  5850 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  5851 users may run a separate document processing stage manually like this:
  5852 "isatool usedir -D output HOL Test && isatool document Test/output";
  5853 
  5854 * theory dependency graph may now be incorporated into documents;
  5855 isatool usedir -g true will produce session_graph.eps/.pdf for use
  5856 with \includegraphics of LaTeX;
  5857 
  5858 * proper spacing of consecutive markup elements, especially text
  5859 blocks after section headings;
  5860 
  5861 * support bold style (for single symbols only), input syntax is like
  5862 this: "\<^bold>\<alpha>" or "\<^bold>A";
  5863 
  5864 * \<bullet> is now output as bold \cdot by default, which looks much
  5865 better in printed text;
  5866 
  5867 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  5868 note that these symbols are currently unavailable in Proof General /
  5869 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  5870 
  5871 * isatool latex no longer depends on changed TEXINPUTS, instead
  5872 isatool document copies the Isabelle style files to the target
  5873 location;
  5874 
  5875 
  5876 *** Isar ***
  5877 
  5878 * Pure/Provers: improved proof by cases and induction;
  5879   - 'case' command admits impromptu naming of parameters (such as
  5880     "case (Suc n)");
  5881   - 'induct' method divinates rule instantiation from the inductive
  5882     claim; no longer requires excessive ?P bindings for proper
  5883     instantiation of cases;
  5884   - 'induct' method properly enumerates all possibilities of set/type
  5885     rules; as a consequence facts may be also passed through *type*
  5886     rules without further ado;
  5887   - 'induct' method now derives symbolic cases from the *rulified*
  5888     rule (before it used to rulify cases stemming from the internal
  5889     atomized version); this means that the context of a non-atomic
  5890     statement becomes is included in the hypothesis, avoiding the
  5891     slightly cumbersome show "PROP ?case" form;
  5892   - 'induct' may now use elim-style induction rules without chaining
  5893     facts, using ``missing'' premises from the goal state; this allows
  5894     rules stemming from inductive sets to be applied in unstructured
  5895     scripts, while still benefitting from proper handling of non-atomic
  5896     statements; NB: major inductive premises need to be put first, all
  5897     the rest of the goal is passed through the induction;
  5898   - 'induct' proper support for mutual induction involving non-atomic
  5899     rule statements (uses the new concept of simultaneous goals, see
  5900     below);
  5901   - append all possible rule selections, but only use the first
  5902     success (no backtracking);
  5903   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  5904   - undeclared rule case names default to numbers 1, 2, 3, ...;
  5905   - added 'print_induct_rules' (covered by help item in recent Proof
  5906     General versions);
  5907   - moved induct/cases attributes to Pure, methods to Provers;
  5908   - generic method setup instantiated for FOL and HOL;
  5909 
  5910 * Pure: support multiple simultaneous goal statements, for example
  5911 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  5912 meta-level mechanism, this acts as if several individual goals had
  5913 been stated separately; in particular common proof methods need to be
  5914 repeated in order to cover all claims; note that a single elimination
  5915 step is *not* sufficient to establish the two conjunctions, so this
  5916 fails:
  5917 
  5918   assume "A & B" then have A and B ..   (*".." fails*)
  5919 
  5920 better use "obtain" in situations as above; alternative refer to
  5921 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  5922 
  5923 * Pure: proper integration with ``locales''; unlike the original
  5924 version by Florian Kammller, Isar locales package high-level proof
  5925 contexts rather than raw logical ones (e.g. we admit to include
  5926 attributes everywhere); operations on locales include merge and
  5927 rename; support for implicit arguments (``structures''); simultaneous
  5928 type-inference over imports and text; see also HOL/ex/Locales.thy for
  5929 some examples;
  5930 
  5931 * Pure: the following commands have been ``localized'', supporting a
  5932 target locale specification "(in name)": 'lemma', 'theorem',
  5933 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  5934 stored both within the locale and at the theory level (exported and
  5935 qualified by the locale name);
  5936 
  5937 * Pure: theory goals may now be specified in ``long'' form, with
  5938 ad-hoc contexts consisting of arbitrary locale elements. for example
  5939 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  5940 definitions may be given, too); the result is a meta-level rule with
  5941 the context elements being discharged in the obvious way;
  5942 
  5943 * Pure: new proof command 'using' allows to augment currently used
  5944 facts after a goal statement ('using' is syntactically analogous to
  5945 'apply', but acts on the goal's facts only); this allows chained facts
  5946 to be separated into parts given before and after a claim, as in
  5947 ``from a and b have C using d and e <proof>'';
  5948 
  5949 * Pure: renamed "antecedent" case to "rule_context";
  5950 
  5951 * Pure: new 'judgment' command records explicit information about the
  5952 object-logic embedding (used by several tools internally); no longer
  5953 use hard-wired "Trueprop";
  5954 
  5955 * Pure: added 'corollary' command;
  5956 
  5957 * Pure: fixed 'token_translation' command;
  5958 
  5959 * Pure: removed obsolete 'exported' attribute;
  5960 
  5961 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  5962 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  5963 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  5964 
  5965 * Pure: method 'atomize' presents local goal premises as object-level
  5966 statements (atomic meta-level propositions); setup controlled via
  5967 rewrite rules declarations of 'atomize' attribute; example
  5968 application: 'induct' method with proper rule statements in improper
  5969 proof *scripts*;
  5970 
  5971 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  5972 now consider the syntactic context of assumptions, giving a better
  5973 chance to get type-inference of the arguments right (this is
  5974 especially important for locales);
  5975 
  5976 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  5977 mode;
  5978 
  5979 * Pure/obtain: the formal conclusion "thesis", being marked as
  5980 ``internal'', may no longer be reference directly in the text;
  5981 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  5982 situations;
  5983 
  5984 * Pure: generic 'sym' attribute which declares a rule both as pure
  5985 'elim?' and for the 'symmetric' operation;
  5986 
  5987 * Pure: marginal comments ``--'' may now occur just anywhere in the
  5988 text; the fixed correlation with particular command syntax has been
  5989 discontinued;
  5990 
  5991 * Pure: new method 'rules' is particularly well-suited for proof
  5992 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  5993 but often produces more compact proof terms with less detours;
  5994 
  5995 * Pure/Provers/classical: simplified integration with pure rule
  5996 attributes and methods; the classical "intro?/elim?/dest?"
  5997 declarations coincide with the pure ones; the "rule" method no longer
  5998 includes classically swapped intros; "intro" and "elim" methods no
  5999 longer pick rules from the context; also got rid of ML declarations
  6000 AddXIs/AddXEs/AddXDs; all of this has some potential for
  6001 INCOMPATIBILITY;
  6002 
  6003 * Provers/classical: attribute 'swapped' produces classical inversions
  6004 of introduction rules;
  6005 
  6006 * Provers/simplifier: 'simplified' attribute may refer to explicit
  6007 rules instead of full simplifier context; 'iff' attribute handles
  6008 conditional rules;
  6009 
  6010 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  6011 
  6012 * HOL: 'recdef' now fails on unfinished automated proofs, use
  6013 "(permissive)" option to recover old behavior;
  6014 
  6015 * HOL: 'inductive' no longer features separate (collective) attributes
  6016 for 'intros' (was found too confusing);
  6017 
  6018 * HOL: properly declared induction rules less_induct and
  6019 wf_induct_rule;
  6020 
  6021 
  6022 *** HOL ***
  6023 
  6024 * HOL: moved over to sane numeral syntax; the new policy is as
  6025 follows:
  6026 
  6027   - 0 and 1 are polymorphic constants, which are defined on any
  6028   numeric type (nat, int, real etc.);
  6029 
  6030   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  6031   binary representation internally;
  6032 
  6033   - type nat has special constructor Suc, and generally prefers Suc 0
  6034   over 1::nat and Suc (Suc 0) over 2::nat;
  6035 
  6036 This change may cause significant problems of INCOMPATIBILITY; here
  6037 are some hints on converting existing sources:
  6038 
  6039   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  6040   entities, so expressions involving "-" (unary or binary minus) need
  6041   to be spaced properly;
  6042 
  6043   - existing occurrences of "1" may need to be constraint "1::nat" or
  6044   even replaced by Suc 0; similar for old "2";
  6045 
  6046   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  6047 
  6048   - remove all special provisions on numerals in proofs;
  6049 
  6050 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  6051 representation (depends on bin_arith_simps in the default context);
  6052 
  6053 * HOL: symbolic syntax for x^2 (numeral 2);
  6054 
  6055 * HOL: the class of all HOL types is now called "type" rather than
  6056 "term"; INCOMPATIBILITY, need to adapt references to this type class
  6057 in axclass/classes, instance/arities, and (usually rare) occurrences
  6058 in typings (of consts etc.); internally the class is called
  6059 "HOL.type", ML programs should refer to HOLogic.typeS;
  6060 
  6061 * HOL/record package improvements:
  6062   - new derived operations "fields" to build a partial record section,
  6063     "extend" to promote a fixed record to a record scheme, and
  6064     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  6065     declared as simp by default;
  6066   - shared operations ("more", "fields", etc.) now need to be always
  6067     qualified) --- potential INCOMPATIBILITY;
  6068   - removed "make_scheme" operations (use "make" with "extend") --
  6069     INCOMPATIBILITY;
  6070   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  6071   - provides cases/induct rules for use with corresponding Isar
  6072     methods (for concrete records, record schemes, concrete more
  6073     parts, and schematic more parts -- in that order);
  6074   - internal definitions directly based on a light-weight abstract
  6075     theory of product types over typedef rather than datatype;
  6076 
  6077 * HOL: generic code generator for generating executable ML code from
  6078 specifications; specific support for HOL constructs such as inductive
  6079 datatypes and sets, as well as recursive functions; can be invoked
  6080 via 'generate_code' theory section;
  6081 
  6082 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  6083 
  6084 * HOL: consolidated and renamed several theories.  In particular:
  6085         Ord.thy has been absorbed into HOL.thy
  6086         String.thy has been absorbed into List.thy
  6087 
  6088 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  6089 (beware of argument permutation!);
  6090 
  6091 * HOL: linorder_less_split superseded by linorder_cases;
  6092 
  6093 * HOL/List: "nodups" renamed to "distinct";
  6094 
  6095 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  6096 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  6097   - Ex_def has changed, now need to use some_eq_ex
  6098 
  6099 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  6100 in this (rare) case use:
  6101 
  6102   delSWrapper "split_all_tac"
  6103   addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
  6104 
  6105 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
  6106 MAY FAIL;
  6107 
  6108 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
  6109 Isabelle's type classes, ^ on functions and relations has too general
  6110 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be
  6111 necessary to attach explicit type constraints;
  6112 
  6113 * HOL/Relation: the prefix name of the infix "O" has been changed from
  6114 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been
  6115 renamed accordingly (eg "compI" -> "rel_compI").
  6116 
  6117 * HOL: syntax translations now work properly with numerals and records
  6118 expressions;
  6119 
  6120 * HOL: bounded abstraction now uses syntax "%" / "\<lambda>" instead
  6121 of "lam" -- INCOMPATIBILITY;
  6122 
  6123 * HOL: got rid of some global declarations (potential INCOMPATIBILITY
  6124 for ML tools): const "()" renamed "Product_Type.Unity", type "unit"
  6125 renamed "Product_Type.unit";
  6126 
  6127 * HOL: renamed rtrancl_into_rtrancl2 to converse_rtrancl_into_rtrancl
  6128 
  6129 * HOL: removed obsolete theorem "optionE" (use "option.exhaust", or
  6130 the "cases" method);
  6131 
  6132 * HOL/GroupTheory: group theory examples including Sylow's theorem (by
  6133 Florian Kammller);
  6134 
  6135 * HOL/IMP: updated and converted to new-style theory format; several
  6136 parts turned into readable document, with proper Isar proof texts and
  6137 some explanations (by Gerwin Klein);
  6138 
  6139 * HOL-Real: added Complex_Numbers (by Gertrud Bauer);
  6140 
  6141 * HOL-Hyperreal is now a logic image;
  6142 
  6143 
  6144 *** HOLCF ***
  6145 
  6146 * Isar: consts/constdefs supports mixfix syntax for continuous
  6147 operations;
  6148 
  6149 * Isar: domain package adapted to new-style theory format, e.g. see
  6150 HOLCF/ex/Dnat.thy;
  6151 
  6152 * theory Lift: proper use of rep_datatype lift instead of ML hacks --
  6153 potential INCOMPATIBILITY; now use plain induct_tac instead of former
  6154 lift.induct_tac, always use UU instead of Undef;
  6155 
  6156 * HOLCF/IMP: updated and converted to new-style theory;
  6157 
  6158 
  6159 *** ZF ***
  6160 
  6161 * Isar: proper integration of logic-specific tools and packages,
  6162 including theory commands '(co)inductive', '(co)datatype',
  6163 'rep_datatype', 'inductive_cases', as well as methods 'ind_cases',
  6164 'induct_tac', 'case_tac', and 'typecheck' (with attribute 'TC');
  6165 
  6166 * theory Main no longer includes AC; for the Axiom of Choice, base
  6167 your theory on Main_ZFC;
  6168 
  6169 * the integer library now covers quotients and remainders, with many
  6170 laws relating division to addition, multiplication, etc.;
  6171 
  6172 * ZF/UNITY: Chandy and Misra's UNITY is now available in ZF, giving a
  6173 typeless version of the formalism;
  6174 
  6175 * ZF/AC, Coind, IMP, Resid: updated and converted to new-style theory
  6176 format;
  6177 
  6178 * ZF/Induct: new directory for examples of inductive definitions,
  6179 including theory Multiset for multiset orderings; converted to
  6180 new-style theory format;
  6181 
  6182 * ZF: many new theorems about lists, ordinals, etc.;
  6183 
  6184 
  6185 *** General ***
  6186 
  6187 * Pure/kernel: meta-level proof terms (by Stefan Berghofer); reference
  6188 variable proof controls level of detail: 0 = no proofs (only oracle
  6189 dependencies), 1 = lemma dependencies, 2 = compact proof terms; see
  6190 also ref manual for further ML interfaces;
  6191 
  6192 * Pure/axclass: removed obsolete ML interface
  6193 goal_subclass/goal_arity;
  6194 
  6195 * Pure/syntax: new token syntax "num" for plain numerals (without "#"
  6196 of "xnum"); potential INCOMPATIBILITY, since -0, -1 etc. are now
  6197 separate tokens, so expressions involving minus need to be spaced
  6198 properly;
  6199 
  6200 * Pure/syntax: support non-oriented infixes, using keyword "infix"
  6201 rather than "infixl" or "infixr";
  6202 
  6203 * Pure/syntax: concrete syntax for dummy type variables admits genuine
  6204 sort constraint specifications in type inference; e.g. "x::_::foo"
  6205 ensures that the type of "x" is of sort "foo" (but not necessarily a
  6206 type variable);
  6207 
  6208 * Pure/syntax: print modes "type_brackets" and "no_type_brackets"
  6209 control output of nested => (types); the default behavior is
  6210 "type_brackets";
  6211 
  6212 * Pure/syntax: builtin parse translation for "_constify" turns valued
  6213 tokens into AST constants;
  6214 
  6215 * Pure/syntax: prefer later declarations of translations and print
  6216 translation functions; potential INCOMPATIBILITY: need to reverse
  6217 multiple declarations for same syntax element constant;
  6218 
  6219 * Pure/show_hyps reset by default (in accordance to existing Isar
  6220 practice);
  6221 
  6222 * Provers/classical: renamed addaltern to addafter, addSaltern to
  6223 addSafter;
  6224 
  6225 * Provers/clasimp: ``iff'' declarations now handle conditional rules
  6226 as well;
  6227 
  6228 * system: tested support for MacOS X; should be able to get Isabelle +
  6229 Proof General to work in a plain Terminal after installing Poly/ML
  6230 (e.g. from the Isabelle distribution area) and GNU bash alone
  6231 (e.g. from http://www.apple.com); full X11, XEmacs and X-Symbol