NEWS
author wenzelm
Fri Jan 07 23:10:33 2011 +0100 (2011-01-07)
changeset 41456 006d85ad56d3
parent 41440 3e0fc4a54ca1
child 41509 c86889cf295b
permissions -rw-r--r--
allow spaces in $SPASS_HOME value;
     1 Isabelle NEWS -- history user-relevant changes
     2 ==============================================
     3 
     4 New in this Isabelle version
     5 ----------------------------
     6 
     7 *** General ***
     8 
     9 * Significantly improved Isabelle/Isar implementation manual.
    10 
    11 * Source files are always encoded as UTF-8, instead of old-fashioned
    12 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
    13 the following package declarations:
    14 
    15   \usepackage[utf8]{inputenc}
    16   \usepackage{textcomp}
    17 
    18 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
    19 a Unicode character is treated as a single symbol, not a sequence of
    20 non-ASCII bytes as before.  Since Isabelle/ML string literals may
    21 contain symbols without further backslash escapes, Unicode can now be
    22 used here as well.  Recall that Symbol.explode in ML provides a
    23 consistent view on symbols, while raw explode (or String.explode)
    24 merely give a byte-oriented representation.
    25 
    26 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
    27 (and thus refers to something like $HOME/.isabelle/IsabelleXXXX),
    28 while the default heap location within that directory lacks that extra
    29 suffix.  This isolates multiple Isabelle installations from each
    30 other, avoiding problems with old settings in new versions.
    31 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
    32 
    33 * Theory loading: only the master source file is looked-up in the
    34 implicit load path, all other files are addressed relatively to its
    35 directory.  Minor INCOMPATIBILITY, subtle change in semantics.
    36 
    37 * Special treatment of ML file names has been discontinued.
    38 Historically, optional extensions .ML or .sml were added on demand --
    39 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
    40 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
    41 
    42 * Various options that affect pretty printing etc. are now properly
    43 handled within the context via configuration options, instead of
    44 unsynchronized references or print modes.  There are both ML Config.T
    45 entities and Isar declaration attributes to access these.
    46 
    47   ML (Config.T)                 Isar (attribute)
    48 
    49   eta_contract                  eta_contract
    50   show_brackets                 show_brackets
    51   show_sorts                    show_sorts
    52   show_types                    show_types
    53   show_question_marks           show_question_marks
    54   show_consts                   show_consts
    55   show_abbrevs                  show_abbrevs
    56 
    57   Syntax.ast_trace              syntax_ast_trace
    58   Syntax.ast_stat               syntax_ast_stat
    59   Syntax.ambiguity_level        syntax_ambiguity_level
    60 
    61   Goal_Display.goals_limit      goals_limit
    62   Goal_Display.show_main_goal   show_main_goal
    63 
    64   Method.rule_trace             rule_trace
    65 
    66   Thy_Output.display            thy_output_display
    67   Thy_Output.quotes             thy_output_quotes
    68   Thy_Output.indent             thy_output_indent
    69   Thy_Output.source             thy_output_source
    70   Thy_Output.break              thy_output_break
    71 
    72 Note that corresponding "..._default" references in ML may only be
    73 changed globally at the ROOT session setup, but *not* within a theory.
    74 The option "show_abbrevs" supersedes the former print mode
    75 "no_abbrevs" with inverted meaning.
    76 
    77 * More systematic naming of some configuration options.
    78 INCOMPATIBILITY.
    79 
    80   trace_simp  ~>  simp_trace
    81   debug_simp  ~>  simp_debug
    82 
    83 * Support for real valued configuration options, using simplistic
    84 floating-point notation that coincides with the inner syntax for
    85 float_token.
    86 
    87 * Theory loader: implicit load path is considered legacy.  Use
    88 explicit file specifications instead, relatively to the directory of
    89 the enclosing theory file.
    90 
    91 
    92 *** Pure ***
    93 
    94 * Command 'type_synonym' (with single argument) replaces somewhat
    95 outdated 'types', which is still available as legacy feature for some
    96 time.
    97 
    98 * Command 'nonterminal' (with 'and' separated list of arguments)
    99 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   100 
   101 * Command 'notepad' replaces former 'example_proof' for
   102 experimentation in Isar without any result.  INCOMPATIBILITY.
   103 
   104 * Support for real valued preferences (with approximative PGIP type).
   105 
   106 * Locale interpretation commands 'interpret' and 'sublocale' accept
   107 lists of equations to map definitions in a locale to appropriate
   108 entities in the context of the interpretation.  The 'interpretation'
   109 command already provided this functionality.
   110 
   111 * New diagnostic command 'print_dependencies' prints the locale
   112 instances that would be activated if the specified expression was
   113 interpreted in the current context.  Variant 'print_dependencies!'
   114 assumes a context without interpretations.
   115 
   116 * Diagnostic command 'print_interps' prints interpretations in proofs
   117 in addition to interpretations in theories.
   118 
   119 * Discontinued obsolete 'global' and 'local' commands to manipulate
   120 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   121 Sign.root_path and Sign.local_path may be applied directly where this
   122 feature is still required for historical reasons.
   123 
   124 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   125 'definition' instead.
   126 
   127 * Document antiquotations @{class} and @{type} print classes and type
   128 constructors.
   129 
   130 * Document antiquotation @{file} checks file/directory entries within
   131 the local file system.
   132 
   133 
   134 *** HOL ***
   135 
   136 * Functions can be declared as coercions and type inference will add
   137 them as necessary upon input of a term. In theory Complex_Main,
   138 real :: nat => real and real :: int => real are declared as
   139 coercions. A new coercion function f is declared like this:
   140 
   141   declare [[coercion f]]
   142 
   143 To lift coercions through type constructors (eg from nat => real to
   144 nat list => real list), map functions can be declared, e.g.
   145 
   146   declare [[coercion_map map]]
   147 
   148 Currently coercion inference is activated only in theories including
   149 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   150 the configuration option "coercion_enabled", e.g. it can be enabled in
   151 other theories like this:
   152 
   153   declare [[coercion_enabled]]
   154 
   155 * New command 'partial_function' provides basic support for recursive
   156 function definitions over complete partial orders. Concrete instances
   157 are provided for i) the option type, ii) tail recursion on arbitrary
   158 types, and iii) the heap monad of Imperative_HOL. See
   159 HOL/ex/Fundefs.thy and HOL/Imperative_HOL/ex/Linked_Lists.thy for
   160 examples.
   161 
   162 * Scala (2.8 or higher) has been added to the target languages of the
   163 code generator.
   164 
   165 * Inductive package: offers new command 'inductive_simps' to
   166 automatically derive instantiated and simplified equations for
   167 inductive predicates, similar to 'inductive_cases'.
   168 
   169 * Function package: .psimps rules are no longer implicitly declared
   170 [simp].  INCOMPATIBILITY.
   171 
   172 * Datatype package: theorems generated for executable equality (class
   173 eq) carry proper names and are treated as default code equations.
   174 
   175 * New command 'type_lifting' allows to register properties on
   176 the functorial structure of types.
   177 
   178 * Weaker versions of the "meson" and "metis" proof methods are now
   179 available in "HOL-Plain", without dependency on "Hilbert_Choice". The
   180 proof methods become more powerful after "Hilbert_Choice" is loaded in
   181 "HOL-Main".
   182 
   183 * Improved infrastructure for term evaluation using code generator
   184 techniques, in particular static evaluation conversions.
   185 
   186 * Code generator: globbing constant expressions "*" and "Theory.*"
   187 have been replaced by the more idiomatic "_" and "Theory._".
   188 INCOMPATIBILITY.
   189 
   190 * Code generator: export_code without explicit file declaration prints
   191 to standard output.  INCOMPATIBILITY.
   192 
   193 * Code generator: do not print function definitions for case
   194 combinators any longer.
   195 
   196 * Simplification with rules determined by code generator
   197 with code_simp.ML and method code_simp.
   198 
   199 * Records: logical foundation type for records does not carry a '_type'
   200 suffix any longer.  INCOMPATIBILITY.
   201 
   202 * Code generation for records: more idiomatic representation of record
   203 types.  Warning: records are not covered by ancient SML code
   204 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   205 rep_datatype declaration helps to succeed then:
   206 
   207   record 'a foo = ...
   208   ...
   209   rep_datatype foo_ext ...
   210 
   211 * Quickcheck now by default uses exhaustive testing instead of random
   212 testing.  Random testing can be invoked by quickcheck[random],
   213 exhaustive testing by quickcheck[exhaustive].
   214 
   215 * Quickcheck instantiates polymorphic types with small finite
   216 datatypes by default. This enables a simple execution mechanism to
   217 handle quantifiers and function equality over the finite datatypes.
   218 
   219 * Quickcheck's generator for random generation is renamed from "code"
   220 to "random".  INCOMPATIBILITY.
   221 
   222 * Quickcheck now has a configurable time limit which is set to 30
   223 seconds by default. This can be changed by adding [timeout = n] to the
   224 quickcheck command. The time limit for Auto Quickcheck is still set
   225 independently.
   226 
   227 * Quickcheck in locales considers interpretations of that locale for
   228 counter example search.
   229 
   230 * Sledgehammer:
   231   - Added "smt" and "remote_smt" provers based on the "smt" proof method. See
   232     the Sledgehammer manual for details ("isabelle doc sledgehammer").
   233   - Renamed lemmas:
   234     COMBI_def ~> Meson.COMBI_def
   235     COMBK_def ~> Meson.COMBK_def
   236     COMBB_def ~> Meson.COMBB_def
   237     COMBC_def ~> Meson.COMBC_def
   238     COMBS_def ~> Meson.COMBS_def
   239     abs_I ~> Meson.abs_I
   240     abs_K ~> Meson.abs_K
   241     abs_B ~> Meson.abs_B
   242     abs_C ~> Meson.abs_C
   243     abs_S ~> Meson.abs_S
   244     INCOMPATIBILITY.
   245   - Renamed commands:
   246     sledgehammer atp_info ~> sledgehammer running_provers
   247     sledgehammer atp_kill ~> sledgehammer kill_provers
   248     sledgehammer available_atps ~> sledgehammer available_provers
   249     INCOMPATIBILITY.
   250   - Renamed options:
   251     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   252     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   253     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   254     (and "ms" and "min" are no longer supported)
   255     INCOMPATIBILITY.
   256 
   257 * Metis and Meson now have configuration options "meson_trace",
   258 "metis_trace", and "metis_verbose" that can be enabled to diagnose
   259 these tools. E.g.
   260 
   261     using [[metis_trace = true]]
   262 
   263 * Nitpick:
   264   - Renamed options:
   265     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   266     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   267     INCOMPATIBILITY.
   268   - Now requires Kodkodi 1.2.9. INCOMPATIBILITY.
   269   - Added support for partial quotient types.
   270   - Added local versions of the "Nitpick.register_xxx" functions.
   271   - Added "whack" option.
   272   - Allow registration of quotient types as codatatypes.
   273   - Improved "merge_type_vars" option to merge more types.
   274   - Removed unsound "fast_descrs" option.
   275   - Added custom symmetry breaking for datatypes, making it possible to reach
   276     higher cardinalities.
   277   - Prevent the expansion of too large definitions.
   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.
   284 
   285 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   286 i.e., "remote_cvc3" and "remote_z3".
   287 
   288 * Added basic SMT support for datatypes, records, and typedefs
   289 using the oracle mode (no proofs).  Direct support of pairs has been
   290 dropped in exchange (pass theorems fst_conv snd_conv pair_collapse to
   291 the SMT support for a similar behaviour).  MINOR INCOMPATIBILITY.
   292 
   293 * Changed SMT configuration options:
   294   - Renamed:
   295     z3_proofs ~> smt_oracle (with inverted meaning)
   296     z3_trace_assms ~> smt_trace_used_facts
   297     INCOMPATIBILITY.
   298   - Added:
   299     smt_verbose
   300     smt_random_seed
   301     smt_datatypes
   302     smt_infer_triggers
   303     smt_monomorph_limit
   304     cvc3_options
   305     remote_cvc3_options
   306     remote_z3_options
   307     yices_options
   308 
   309 * Boogie output files (.b2i files) need to be declared in the theory
   310 header.
   311 
   312 * Dropped syntax for old primrec package.  INCOMPATIBILITY.
   313 
   314 * Multivariate Analysis: Introduced a type class for euclidean
   315 space. Most theorems are now stated in terms of euclidean spaces
   316 instead of finite cartesian products.
   317 
   318   types
   319     real ^ 'n ~>  'a::real_vector
   320               ~>  'a::euclidean_space
   321               ~>  'a::ordered_euclidean_space
   322         (depends on your needs)
   323 
   324   constants
   325      _ $ _        ~> _ $$ _
   326      \<chi> x. _  ~> \<chi>\<chi> x. _
   327      CARD('n)     ~> DIM('a)
   328 
   329 Also note that the indices are now natural numbers and not from some
   330 finite type. Finite cartesian products of euclidean spaces, products
   331 of euclidean spaces the real and complex numbers are instantiated to
   332 be euclidean_spaces.  INCOMPATIBILITY.
   333 
   334 * Probability: Introduced pextreal as positive extended real numbers.
   335 Use pextreal as value for measures. Introduce the Radon-Nikodym
   336 derivative, product spaces and Fubini's theorem for arbitrary sigma
   337 finite measures. Introduces Lebesgue measure based on the integral in
   338 Multivariate Analysis.  INCOMPATIBILITY.
   339 
   340 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   341 INCOMPATIBILITY.
   342 
   343 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   344 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   345 INCOMPATIBILITY.
   346 
   347 * Theory SetsAndFunctions has been split into Function_Algebras and
   348 Set_Algebras; canonical names for instance definitions for functions;
   349 various improvements.  INCOMPATIBILITY.
   350 
   351 * Theory Multiset provides stable quicksort implementation of
   352 sort_key.
   353 
   354 * Theory Enum (for explicit enumerations of finite types) is now part
   355 of the HOL-Main image. INCOMPATIBILITY: all constants of the Enum
   356 theory now have to be referred to by its qualified name.
   357 
   358   enum    ~>  Enum.enum
   359   nlists  ~>  Enum.nlists
   360   product ~>  Enum.product
   361 
   362 * Removed simplifier congruence rule of "prod_case", as has for long
   363 been the case with "split".  INCOMPATIBILITY.
   364 
   365 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   366 
   367 * Removed [split_format ... and ... and ...] version of
   368 [split_format].  Potential INCOMPATIBILITY.
   369 
   370 * Predicate "sorted" now defined inductively, with
   371 nice induction rules.  INCOMPATIBILITY: former sorted.simps now
   372 named sorted_simps.
   373 
   374 * Constant "contents" renamed to "the_elem", to free the generic name
   375 contents for other uses.  INCOMPATIBILITY.
   376 
   377 * Renamed class eq and constant eq (for code generation) to class
   378 equal and constant equal, plus renaming of related facts and various
   379 tuning.  INCOMPATIBILITY.
   380 
   381 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   382 
   383 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".  INCOMPATIBILITY.
   384 
   385 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   386 avoid confusion with finite sets.  INCOMPATIBILITY.
   387 
   388 * Multiset.thy: renamed empty_idemp ~> empty_neutral.  INCOMPATIBILITY.
   389 
   390 * Abandoned locales equiv, congruent and congruent2 for equivalence
   391 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   392 for congruent(2)).
   393 
   394 * Some previously unqualified names have been qualified:
   395 
   396   types
   397     bool ~> HOL.bool
   398     nat ~> Nat.nat
   399 
   400   constants
   401     Trueprop ~> HOL.Trueprop
   402     True ~> HOL.True
   403     False ~> HOL.False
   404     op & ~> HOL.conj
   405     op | ~> HOL.disj
   406     op --> ~> HOL.implies
   407     op = ~> HOL.eq
   408     Not ~> HOL.Not
   409     The ~> HOL.The
   410     All ~> HOL.All
   411     Ex ~> HOL.Ex
   412     Ex1 ~> HOL.Ex1
   413     Let ~> HOL.Let
   414     If ~> HOL.If
   415     Ball ~> Set.Ball
   416     Bex ~> Set.Bex
   417     Suc ~> Nat.Suc
   418     Pair ~> Product_Type.Pair
   419     fst ~> Product_Type.fst
   420     snd ~> Product_Type.snd
   421     curry ~> Product_Type.curry
   422     op : ~> Set.member
   423     Collect ~> Set.Collect
   424 
   425 INCOMPATIBILITY.
   426 
   427 * More canonical naming convention for some fundamental definitions:
   428 
   429     bot_bool_eq ~> bot_bool_def
   430     top_bool_eq ~> top_bool_def
   431     inf_bool_eq ~> inf_bool_def
   432     sup_bool_eq ~> sup_bool_def
   433     bot_fun_eq  ~> bot_fun_def
   434     top_fun_eq  ~> top_fun_def
   435     inf_fun_eq  ~> inf_fun_def
   436     sup_fun_eq  ~> sup_fun_def
   437 
   438 INCOMPATIBILITY.
   439 
   440 * More stylized fact names:
   441 
   442   expand_fun_eq ~> fun_eq_iff
   443   expand_set_eq ~> set_eq_iff
   444   set_ext       ~> set_eqI
   445   nat_number    ~> eval_nat_numeral
   446 
   447 INCOMPATIBILITY.
   448 
   449 * Refactoring of code-generation specific operations in List.thy
   450 
   451   constants
   452     null ~> List.null
   453 
   454   facts
   455     mem_iff ~> member_def
   456     null_empty ~> null_def
   457 
   458 INCOMPATIBILITY.  Note that these were not supposed to be used
   459 regularly unless for striking reasons; their main purpose was code
   460 generation.
   461 
   462 Various operations from the Haskell prelude are used for generating
   463 Haskell code.
   464 
   465 * MESON: Renamed lemmas:
   466   meson_not_conjD ~> Meson.not_conjD
   467   meson_not_disjD ~> Meson.not_disjD
   468   meson_not_notD ~> Meson.not_notD
   469   meson_not_allD ~> Meson.not_allD
   470   meson_not_exD ~> Meson.not_exD
   471   meson_imp_to_disjD ~> Meson.imp_to_disjD
   472   meson_not_impD ~> Meson.not_impD
   473   meson_iff_to_disjD ~> Meson.iff_to_disjD
   474   meson_not_iffD ~> Meson.not_iffD
   475   meson_not_refl_disj_D ~> Meson.not_refl_disj_D
   476   meson_conj_exD1 ~> Meson.conj_exD1
   477   meson_conj_exD2 ~> Meson.conj_exD2
   478   meson_disj_exD ~> Meson.disj_exD
   479   meson_disj_exD1 ~> Meson.disj_exD1
   480   meson_disj_exD2 ~> Meson.disj_exD2
   481   meson_disj_assoc ~> Meson.disj_assoc
   482   meson_disj_comm ~> Meson.disj_comm
   483   meson_disj_FalseD1 ~> Meson.disj_FalseD1
   484   meson_disj_FalseD2 ~> Meson.disj_FalseD2
   485 INCOMPATIBILITY.
   486 
   487 * "bij f" is now an abbreviation of "bij_betw f UNIV UNIV". "surj f"
   488 is now an abbreviation of "range f = UNIV". The theorems bij_def and
   489 surj_def are unchanged.  INCOMPATIBILITY.
   490 
   491 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   492 "*" and "+" respectively.  INCOMPATIBILITY.
   493 
   494 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   495 Sum_Type.Plus.
   496 
   497 * Constant "split" has been merged with constant "prod_case"; names of
   498 ML functions, facts etc. involving split have been retained so far,
   499 though.  INCOMPATIBILITY.
   500 
   501 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   502 instead.  INCOMPATIBILITY.
   503 
   504 * Removed lemma Option.is_none_none (Duplicate of is_none_def).
   505 INCOMPATIBILITY.
   506 
   507 
   508 *** HOL-Algebra ***
   509 
   510 * Theorems for additive ring operations (locale abelian_monoid and
   511 descendants) are generated by interpretation from their multiplicative
   512 counterparts.  Names (in particular theorem names) have the mandatory
   513 qualifier 'add'.  Previous theorem names are redeclared for
   514 compatibility.
   515 
   516 * Structure 'int_ring' is now an abbreviation (previously a
   517 definition).  This fits more natural with advanced interpretations.
   518 
   519 
   520 *** HOLCF ***
   521 
   522 * The domain package now runs in definitional mode by default: The
   523 former command 'new_domain' is now called 'domain'. To use the domain
   524 package in its original axiomatic mode, use 'domain (unsafe)'.
   525 INCOMPATIBILITY.
   526 
   527 * The new class 'domain' is now the default sort. Class 'predomain' is
   528 an unpointed version of 'domain'. Theories can be updated by replacing
   529 sort annotations as shown below. INCOMPATIBILITY.
   530 
   531   'a::type ~> 'a::countable
   532   'a::cpo  ~> 'a::predomain
   533   'a::pcpo ~> 'a::domain
   534 
   535 * The old type class 'rep' has been superseded by class 'domain'.
   536 Accordingly, users of the definitional package must remove any
   537 'default_sort rep' declarations. INCOMPATIBILITY.
   538 
   539 * The domain package (definitional mode) now supports unpointed
   540 predomain argument types, as long as they are marked 'lazy'. (Strict
   541 arguments must be in class 'domain'.) For example, the following
   542 domain definition now works:
   543 
   544   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   545 
   546 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   547 instances for types from Isabelle/HOL: bool, nat, int, char, 'a + 'b,
   548 'a option, and 'a list. Additionally, it configures fixrec and the
   549 domain package to work with these types. For example:
   550 
   551   fixrec isInl :: "('a + 'b) u -> tr"
   552     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   553 
   554   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   555 
   556 * The '(permissive)' option of fixrec has been replaced with a
   557 per-equation '(unchecked)' option. See HOLCF/Tutorial/Fixrec_ex.thy
   558 for examples. INCOMPATIBILITY.
   559 
   560 * The 'bifinite' class no longer fixes a constant 'approx'; the class
   561 now just asserts that such a function exists. INCOMPATIBILITY.
   562 
   563 * The type 'alg_defl' has been renamed to 'defl'. HOLCF no longer
   564 defines an embedding of type 'a defl into udom by default; instances
   565 of 'bifinite' and 'domain' classes are available in
   566 HOLCF/Library/Defl_Bifinite.thy.
   567 
   568 * The syntax 'REP('a)' has been replaced with 'DEFL('a)'.
   569 
   570 * The predicate 'directed' has been removed. INCOMPATIBILITY.
   571 
   572 * The type class 'finite_po' has been removed. INCOMPATIBILITY.
   573 
   574 * The function 'cprod_map' has been renamed to 'prod_map'.
   575 INCOMPATIBILITY.
   576 
   577 * The monadic bind operator on each powerdomain has new binder syntax
   578 similar to sets, e.g. '\<Union>\<sharp>x\<in>xs. t' represents
   579 'upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)'.
   580 
   581 * The infix syntax for binary union on each powerdomain has changed
   582 from e.g. '+\<sharp>' to '\<union>\<sharp>', for consistency with set
   583 syntax. INCOMPATIBILITY.
   584 
   585 * The constant 'UU' has been renamed to 'bottom'. The syntax 'UU' is
   586 still supported as an input translation.
   587 
   588 * Renamed some theorems (the original names are also still available).
   589   expand_fun_below   ~> fun_below_iff
   590   below_fun_ext      ~> fun_belowI
   591   expand_cfun_eq     ~> cfun_eq_iff
   592   ext_cfun           ~> cfun_eqI
   593   expand_cfun_below  ~> cfun_below_iff
   594   below_cfun_ext     ~> cfun_belowI
   595   cont2cont_Rep_CFun ~> cont2cont_APP
   596 
   597 * The Abs and Rep functions for various types have changed names.
   598 Related theorem names have also changed to match. INCOMPATIBILITY.
   599   Rep_CFun  ~> Rep_cfun
   600   Abs_CFun  ~> Abs_cfun
   601   Rep_Sprod ~> Rep_sprod
   602   Abs_Sprod ~> Abs_sprod
   603   Rep_Ssum  ~> Rep_ssum
   604   Abs_Ssum  ~> Abs_ssum
   605 
   606 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   607 been renamed to *_bottom_iff. INCOMPATIBILITY.
   608 
   609 * Various changes to bisimulation/coinduction with domain package:
   610   - Definitions of 'bisim' constants no longer mention definedness.
   611   - With mutual recursion, 'bisim' predicate is now curried.
   612   - With mutual recursion, each type gets a separate coind theorem.
   613   - Variable names in bisim_def and coinduct rules have changed.
   614 INCOMPATIBILITY.
   615 
   616 * Case combinators generated by the domain package for type 'foo' are
   617 now named 'foo_case' instead of 'foo_when'. INCOMPATIBILITY.
   618 
   619 * Several theorems have been renamed to more accurately reflect the
   620 names of constants and types involved. INCOMPATIBILITY.
   621   thelub_const    ~> lub_const
   622   lub_const       ~> is_lub_const
   623   thelubI         ~> lub_eqI
   624   is_lub_lub      ~> is_lubD2
   625   lubI            ~> is_lub_lub
   626   unique_lub      ~> is_lub_unique
   627   is_ub_lub       ~> is_lub_rangeD1
   628   lub_bin_chain   ~> is_lub_bin_chain
   629   lub_fun         ~> is_lub_fun
   630   thelub_fun      ~> lub_fun
   631   thelub_cfun     ~> lub_cfun
   632   thelub_Pair     ~> lub_Pair
   633   lub_cprod       ~> is_lub_prod
   634   thelub_cprod    ~> lub_prod
   635   minimal_cprod   ~> minimal_prod
   636   inst_cprod_pcpo ~> inst_prod_pcpo
   637   UU_I            ~> bottomI
   638   compact_UU      ~> compact_bottom
   639   deflation_UU    ~> deflation_bottom
   640   finite_deflation_UU ~> finite_deflation_bottom
   641 
   642 * Many legacy theorem names have been discontinued. INCOMPATIBILITY.
   643   sq_ord_less_eq_trans ~> below_eq_trans
   644   sq_ord_eq_less_trans ~> eq_below_trans
   645   refl_less            ~> below_refl
   646   trans_less           ~> below_trans
   647   antisym_less         ~> below_antisym
   648   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
   649   box_less             ~> box_below
   650   rev_trans_less       ~> rev_below_trans
   651   not_less2not_eq      ~> not_below2not_eq
   652   less_UU_iff          ~> below_UU_iff
   653   flat_less_iff        ~> flat_below_iff
   654   adm_less             ~> adm_below
   655   adm_not_less         ~> adm_not_below
   656   adm_compact_not_less ~> adm_compact_not_below
   657   less_fun_def         ~> below_fun_def
   658   expand_fun_less      ~> fun_below_iff
   659   less_fun_ext         ~> fun_belowI
   660   less_discr_def       ~> below_discr_def
   661   discr_less_eq        ~> discr_below_eq
   662   less_unit_def        ~> below_unit_def
   663   less_cprod_def       ~> below_prod_def
   664   prod_lessI           ~> prod_belowI
   665   Pair_less_iff        ~> Pair_below_iff
   666   fst_less_iff         ~> fst_below_iff
   667   snd_less_iff         ~> snd_below_iff
   668   expand_cfun_less     ~> cfun_below_iff
   669   less_cfun_ext        ~> cfun_belowI
   670   injection_less       ~> injection_below
   671   less_up_def          ~> below_up_def
   672   not_Iup_less         ~> not_Iup_below
   673   Iup_less             ~> Iup_below
   674   up_less              ~> up_below
   675   Def_inject_less_eq   ~> Def_below_Def
   676   Def_less_is_eq       ~> Def_below_iff
   677   spair_less_iff       ~> spair_below_iff
   678   less_sprod           ~> below_sprod
   679   spair_less           ~> spair_below
   680   sfst_less_iff        ~> sfst_below_iff
   681   ssnd_less_iff        ~> ssnd_below_iff
   682   fix_least_less       ~> fix_least_below
   683   dist_less_one        ~> dist_below_one
   684   less_ONE             ~> below_ONE
   685   ONE_less_iff         ~> ONE_below_iff
   686   less_sinlD           ~> below_sinlD
   687   less_sinrD           ~> below_sinrD
   688 
   689 
   690 *** FOL and ZF ***
   691 
   692 * All constant names are now qualified internally and use proper
   693 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
   694 
   695 
   696 
   697 *** ML ***
   698 
   699 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
   700 main functionality is provided by structure Simplifier.
   701 
   702 * Syntax.pretty_priority (default 0) configures the required priority
   703 of pretty-printed output and thus affects insertion of parentheses.
   704 
   705 * Syntax.default_root (default "any") configures the inner syntax
   706 category (nonterminal symbol) for parsing of terms.
   707 
   708 * Former exception Library.UnequalLengths now coincides with
   709 ListPair.UnequalLengths.
   710 
   711 * Renamed raw "explode" function to "raw_explode" to emphasize its
   712 meaning.  Note that internally to Isabelle, Symbol.explode is used in
   713 almost all situations.
   714 
   715 * Discontinued obsolete function sys_error and exception SYS_ERROR.
   716 See implementation manual for further details on exceptions in
   717 Isabelle/ML.
   718 
   719 * Antiquotation @{assert} inlines a function bool -> unit that raises
   720 Fail if the argument is false.  Due to inlining the source position of
   721 failed assertions is included in the error output.
   722 
   723 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
   724 text is in practice always evaluated with a stable theory checkpoint.
   725 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
   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 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 * ML antiquotations @{theory} and @{theory_ref} refer to named
   751 theories from the ancestry of the current context, not any accidental
   752 theory loader state as before.  Potential INCOMPATIBILITY, subtle
   753 change in semantics.
   754 
   755 * Parallel and asynchronous execution requires special care concerning
   756 interrupts.  Structure Exn provides some convenience functions that
   757 avoid working directly with raw Interrupt.  User code must not absorb
   758 interrupts -- intermediate handling (for cleanup etc.) needs to be
   759 followed by re-raising of the original exception.  Another common
   760 source of mistakes are "handle _" patterns, which make the meaning of
   761 the program subject to physical effects of the environment.
   762 
   763 
   764 *** System ***
   765 
   766 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   767 DejaVu Sans.
   768 
   769 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   770 
   771 
   772 
   773 New in Isabelle2009-2 (June 2010)
   774 ---------------------------------
   775 
   776 *** General ***
   777 
   778 * Authentic syntax for *all* logical entities (type classes, type
   779 constructors, term constants): provides simple and robust
   780 correspondence between formal entities and concrete syntax.  Within
   781 the parse tree / AST representations, "constants" are decorated by
   782 their category (class, type, const) and spelled out explicitly with
   783 their full internal name.
   784 
   785 Substantial INCOMPATIBILITY concerning low-level syntax declarations
   786 and translations (translation rules and translation functions in ML).
   787 Some hints on upgrading:
   788 
   789   - Many existing uses of 'syntax' and 'translations' can be replaced
   790     by more modern 'type_notation', 'notation' and 'abbreviation',
   791     which are independent of this issue.
   792 
   793   - 'translations' require markup within the AST; the term syntax
   794     provides the following special forms:
   795 
   796       CONST c   -- produces syntax version of constant c from context
   797       XCONST c  -- literally c, checked as constant from context
   798       c         -- literally c, if declared by 'syntax'
   799 
   800     Plain identifiers are treated as AST variables -- occasionally the
   801     system indicates accidental variables via the error "rhs contains
   802     extra variables".
   803 
   804     Type classes and type constructors are marked according to their
   805     concrete syntax.  Some old translations rules need to be written
   806     for the "type" category, using type constructor application
   807     instead of pseudo-term application of the default category
   808     "logic".
   809 
   810   - 'parse_translation' etc. in ML may use the following
   811     antiquotations:
   812 
   813       @{class_syntax c}   -- type class c within parse tree / AST
   814       @{term_syntax c}    -- type constructor c within parse tree / AST
   815       @{const_syntax c}   -- ML version of "CONST c" above
   816       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
   817 
   818   - Literal types within 'typed_print_translations', i.e. those *not*
   819     represented as pseudo-terms are represented verbatim.  Use @{class
   820     c} or @{type_name c} here instead of the above syntax
   821     antiquotations.
   822 
   823 Note that old non-authentic syntax was based on unqualified base
   824 names, so all of the above "constant" names would coincide.  Recall
   825 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
   826 diagnose syntax problems.
   827 
   828 * Type constructors admit general mixfix syntax, not just infix.
   829 
   830 * Concrete syntax may be attached to local entities without a proof
   831 body, too.  This works via regular mixfix annotations for 'fix',
   832 'def', 'obtain' etc. or via the explicit 'write' command, which is
   833 similar to the 'notation' command in theory specifications.
   834 
   835 * Discontinued unnamed infix syntax (legacy feature for many years) --
   836 need to specify constant name and syntax separately.  Internal ML
   837 datatype constructors have been renamed from InfixName to Infix etc.
   838 Minor INCOMPATIBILITY.
   839 
   840 * Schematic theorem statements need to be explicitly markup as such,
   841 via commands 'schematic_lemma', 'schematic_theorem',
   842 'schematic_corollary'.  Thus the relevance of the proof is made
   843 syntactically clear, which impacts performance in a parallel or
   844 asynchronous interactive environment.  Minor INCOMPATIBILITY.
   845 
   846 * Use of cumulative prems via "!" in some proof methods has been
   847 discontinued (old legacy feature).
   848 
   849 * References 'trace_simp' and 'debug_simp' have been replaced by
   850 configuration options stored in the context. Enabling tracing (the
   851 case of debugging is similar) in proofs works via
   852 
   853   using [[trace_simp = true]]
   854 
   855 Tracing is then active for all invocations of the simplifier in
   856 subsequent goal refinement steps. Tracing may also still be enabled or
   857 disabled via the ProofGeneral settings menu.
   858 
   859 * Separate commands 'hide_class', 'hide_type', 'hide_const',
   860 'hide_fact' replace the former 'hide' KIND command.  Minor
   861 INCOMPATIBILITY.
   862 
   863 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
   864 more efficient than combinations with -q1 or -q2.
   865 
   866 
   867 *** Pure ***
   868 
   869 * Proofterms record type-class reasoning explicitly, using the
   870 "unconstrain" operation internally.  This eliminates all sort
   871 constraints from a theorem and proof, introducing explicit
   872 OFCLASS-premises.  On the proof term level, this operation is
   873 automatically applied at theorem boundaries, such that closed proofs
   874 are always free of sort constraints.  INCOMPATIBILITY for tools that
   875 inspect proof terms.
   876 
   877 * Local theory specifications may depend on extra type variables that
   878 are not present in the result type -- arguments TYPE('a) :: 'a itself
   879 are added internally.  For example:
   880 
   881   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
   882 
   883 * Predicates of locales introduced by classes carry a mandatory
   884 "class" prefix.  INCOMPATIBILITY.
   885 
   886 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
   887 
   888 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
   889 'class' instead.
   890 
   891 * Command 'code_reflect' allows to incorporate generated ML code into
   892 runtime environment; replaces immature code_datatype antiquotation.
   893 INCOMPATIBILITY.
   894 
   895 * Code generator: simple concept for abstract datatypes obeying
   896 invariants.
   897 
   898 * Code generator: details of internal data cache have no impact on the
   899 user space functionality any longer.
   900 
   901 * Methods "unfold_locales" and "intro_locales" ignore non-locale
   902 subgoals.  This is more appropriate for interpretations with 'where'.
   903 INCOMPATIBILITY.
   904 
   905 * Command 'example_proof' opens an empty proof body.  This allows to
   906 experiment with Isar, without producing any persistent result.
   907 
   908 * Commands 'type_notation' and 'no_type_notation' declare type syntax
   909 within a local theory context, with explicit checking of the
   910 constructors involved (in contrast to the raw 'syntax' versions).
   911 
   912 * Commands 'types' and 'typedecl' now work within a local theory
   913 context -- without introducing dependencies on parameters or
   914 assumptions, which is not possible in Isabelle/Pure.
   915 
   916 * Command 'defaultsort' has been renamed to 'default_sort', it works
   917 within a local theory context.  Minor INCOMPATIBILITY.
   918 
   919 
   920 *** HOL ***
   921 
   922 * Command 'typedef' now works within a local theory context -- without
   923 introducing dependencies on parameters or assumptions, which is not
   924 possible in Isabelle/Pure/HOL.  Note that the logical environment may
   925 contain multiple interpretations of local typedefs (with different
   926 non-emptiness proofs), even in a global theory context.
   927 
   928 * New package for quotient types.  Commands 'quotient_type' and
   929 'quotient_definition' may be used for defining types and constants by
   930 quotient constructions.  An example is the type of integers created by
   931 quotienting pairs of natural numbers:
   932 
   933   fun
   934     intrel :: "(nat * nat) => (nat * nat) => bool"
   935   where
   936     "intrel (x, y) (u, v) = (x + v = u + y)"
   937 
   938   quotient_type int = "nat * nat" / intrel
   939     by (auto simp add: equivp_def expand_fun_eq)
   940 
   941   quotient_definition
   942     "0::int" is "(0::nat, 0::nat)"
   943 
   944 The method "lifting" can be used to lift of theorems from the
   945 underlying "raw" type to the quotient type.  The example
   946 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
   947 construction and provides a reasoning infrastructure for finite sets.
   948 
   949 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
   950 clash with new theory Quotient in Main HOL.
   951 
   952 * Moved the SMT binding into the main HOL session, eliminating
   953 separate HOL-SMT session.
   954 
   955 * List membership infix mem operation is only an input abbreviation.
   956 INCOMPATIBILITY.
   957 
   958 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
   959 for future developements; former Library/Word.thy is still present in
   960 the AFP entry RSAPPS.
   961 
   962 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
   963 longer shadowed.  INCOMPATIBILITY.
   964 
   965 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
   966 INCOMPATIBILITY.
   967 
   968 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
   969 INCOMPATIBILITY.
   970 
   971 * Dropped normalizing_semiring etc; use the facts in semiring classes
   972 instead.  INCOMPATIBILITY.
   973 
   974 * Dropped several real-specific versions of lemmas about floor and
   975 ceiling; use the generic lemmas from theory "Archimedean_Field"
   976 instead.  INCOMPATIBILITY.
   977 
   978   floor_number_of_eq         ~> floor_number_of
   979   le_floor_eq_number_of      ~> number_of_le_floor
   980   le_floor_eq_zero           ~> zero_le_floor
   981   le_floor_eq_one            ~> one_le_floor
   982   floor_less_eq_number_of    ~> floor_less_number_of
   983   floor_less_eq_zero         ~> floor_less_zero
   984   floor_less_eq_one          ~> floor_less_one
   985   less_floor_eq_number_of    ~> number_of_less_floor
   986   less_floor_eq_zero         ~> zero_less_floor
   987   less_floor_eq_one          ~> one_less_floor
   988   floor_le_eq_number_of      ~> floor_le_number_of
   989   floor_le_eq_zero           ~> floor_le_zero
   990   floor_le_eq_one            ~> floor_le_one
   991   floor_subtract_number_of   ~> floor_diff_number_of
   992   floor_subtract_one         ~> floor_diff_one
   993   ceiling_number_of_eq       ~> ceiling_number_of
   994   ceiling_le_eq_number_of    ~> ceiling_le_number_of
   995   ceiling_le_zero_eq         ~> ceiling_le_zero
   996   ceiling_le_eq_one          ~> ceiling_le_one
   997   less_ceiling_eq_number_of  ~> number_of_less_ceiling
   998   less_ceiling_eq_zero       ~> zero_less_ceiling
   999   less_ceiling_eq_one        ~> one_less_ceiling
  1000   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1001   ceiling_less_eq_zero       ~> ceiling_less_zero
  1002   ceiling_less_eq_one        ~> ceiling_less_one
  1003   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1004   le_ceiling_eq_zero         ~> zero_le_ceiling
  1005   le_ceiling_eq_one          ~> one_le_ceiling
  1006   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1007   ceiling_subtract_one       ~> ceiling_diff_one
  1008 
  1009 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1010 application of the various fold combinators on finite sets.
  1011 
  1012 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1013 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1014 implementation.  INCOMPATIBILTY.
  1015 
  1016 * Theory Library/Coinductive_List has been removed -- superseded by
  1017 AFP/thys/Coinductive.
  1018 
  1019 * Theory PReal, including the type "preal" and related operations, has
  1020 been removed.  INCOMPATIBILITY.
  1021 
  1022 * Real: new development using Cauchy Sequences.
  1023 
  1024 * Split off theory "Big_Operators" containing setsum, setprod,
  1025 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1026 
  1027 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1028 "Int" etc.  INCOMPATIBILITY.
  1029 
  1030 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1031 
  1032 * New set of rules "ac_simps" provides combined assoc / commute
  1033 rewrites for all interpretations of the appropriate generic locales.
  1034 
  1035 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1036 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1037 appropriate and more consistent names suitable for name prefixes
  1038 within the HOL theories.  INCOMPATIBILITY.
  1039 
  1040 * Some generic constants have been put to appropriate theories:
  1041   - less_eq, less: Orderings
  1042   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1043   - inverse, divide: Rings
  1044 INCOMPATIBILITY.
  1045 
  1046 * More consistent naming of type classes involving orderings (and
  1047 lattices):
  1048 
  1049     lower_semilattice                   ~> semilattice_inf
  1050     upper_semilattice                   ~> semilattice_sup
  1051 
  1052     dense_linear_order                  ~> dense_linorder
  1053 
  1054     pordered_ab_group_add               ~> ordered_ab_group_add
  1055     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1056     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1057     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1058     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1059     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1060     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1061     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1062     pordered_comm_ring                  ~> ordered_comm_ring
  1063     pordered_comm_semiring              ~> ordered_comm_semiring
  1064     pordered_ring                       ~> ordered_ring
  1065     pordered_ring_abs                   ~> ordered_ring_abs
  1066     pordered_semiring                   ~> ordered_semiring
  1067 
  1068     ordered_ab_group_add                ~> linordered_ab_group_add
  1069     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1070     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1071     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1072     ordered_field                       ~> linordered_field
  1073     ordered_field_no_lb                 ~> linordered_field_no_lb
  1074     ordered_field_no_ub                 ~> linordered_field_no_ub
  1075     ordered_field_dense_linear_order    ~> dense_linordered_field
  1076     ordered_idom                        ~> linordered_idom
  1077     ordered_ring                        ~> linordered_ring
  1078     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1079     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1080     ordered_ring_strict                 ~> linordered_ring_strict
  1081     ordered_semidom                     ~> linordered_semidom
  1082     ordered_semiring                    ~> linordered_semiring
  1083     ordered_semiring_1                  ~> linordered_semiring_1
  1084     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1085     ordered_semiring_strict             ~> linordered_semiring_strict
  1086 
  1087   The following slightly odd type classes have been moved to a
  1088   separate theory Library/Lattice_Algebras:
  1089 
  1090     lordered_ab_group_add               ~> lattice_ab_group_add
  1091     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1092     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1093     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1094     lordered_ring                       ~> lattice_ring
  1095 
  1096 INCOMPATIBILITY.
  1097 
  1098 * Refined field classes:
  1099   - classes division_ring_inverse_zero, field_inverse_zero,
  1100     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1101     subsumes former division_by_zero class;
  1102   - numerous lemmas have been ported from field to division_ring.
  1103 INCOMPATIBILITY.
  1104 
  1105 * Refined algebra theorem collections:
  1106   - dropped theorem group group_simps, use algebra_simps instead;
  1107   - dropped theorem group ring_simps, use field_simps instead;
  1108   - proper theorem collection field_simps subsumes former theorem
  1109     groups field_eq_simps and field_simps;
  1110   - dropped lemma eq_minus_self_iff which is a duplicate for
  1111     equal_neg_zero.
  1112 INCOMPATIBILITY.
  1113 
  1114 * Theory Finite_Set and List: some lemmas have been generalized from
  1115 sets to lattices:
  1116 
  1117   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1118   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1119   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1120   union_Union_fold_union        ~> sup_Sup_fold_sup
  1121   Inter_fold_inter              ~> Inf_fold_inf
  1122   Union_fold_union              ~> Sup_fold_sup
  1123   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1124   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1125   INTER_fold_inter              ~> INFI_fold_inf
  1126   UNION_fold_union              ~> SUPR_fold_sup
  1127 
  1128 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1129 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1130 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1131 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1132 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1133 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1134 
  1135 * Reorganized theory Multiset: swapped notation of pointwise and
  1136 multiset order:
  1137 
  1138   - pointwise ordering is instance of class order with standard syntax
  1139     <= and <;
  1140   - multiset ordering has syntax <=# and <#; partial order properties
  1141     are provided by means of interpretation with prefix
  1142     multiset_order;
  1143   - less duplication, less historical organization of sections,
  1144     conversion from associations lists to multisets, rudimentary code
  1145     generation;
  1146   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1147     if needed.
  1148 
  1149 Renamed:
  1150 
  1151   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1152   multi_count_ext  ~>  multiset_ext
  1153   diff_union_inverse2  ~>  diff_union_cancelR
  1154 
  1155 INCOMPATIBILITY.
  1156 
  1157 * Theory Permutation: replaced local "remove" by List.remove1.
  1158 
  1159 * Code generation: ML and OCaml code is decorated with signatures.
  1160 
  1161 * Theory List: added transpose.
  1162 
  1163 * Library/Nat_Bijection.thy is a collection of bijective functions
  1164 between nat and other types, which supersedes the older libraries
  1165 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1166 
  1167   Constants:
  1168   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1169   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1170   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1171   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1172   Countable.pair_encode           ~> prod_encode
  1173   NatIso.prod2nat                 ~> prod_encode
  1174   NatIso.nat2prod                 ~> prod_decode
  1175   NatIso.sum2nat                  ~> sum_encode
  1176   NatIso.nat2sum                  ~> sum_decode
  1177   NatIso.list2nat                 ~> list_encode
  1178   NatIso.nat2list                 ~> list_decode
  1179   NatIso.set2nat                  ~> set_encode
  1180   NatIso.nat2set                  ~> set_decode
  1181 
  1182   Lemmas:
  1183   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1184   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1185   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1186   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1187   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1188   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1189   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1190   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1191   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1192   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1193   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1194   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1195   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1196 
  1197 * Sledgehammer:
  1198   - Renamed ATP commands:
  1199     atp_info     ~> sledgehammer running_atps
  1200     atp_kill     ~> sledgehammer kill_atps
  1201     atp_messages ~> sledgehammer messages
  1202     atp_minimize ~> sledgehammer minimize
  1203     print_atps   ~> sledgehammer available_atps
  1204     INCOMPATIBILITY.
  1205   - Added user's manual ("isabelle doc sledgehammer").
  1206   - Added option syntax and "sledgehammer_params" to customize
  1207     Sledgehammer's behavior.  See the manual for details.
  1208   - Modified the Isar proof reconstruction code so that it produces
  1209     direct proofs rather than proofs by contradiction.  (This feature
  1210     is still experimental.)
  1211   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1212     full-typed mode.
  1213   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1214 
  1215 * Nitpick:
  1216   - Added and implemented "binary_ints" and "bits" options.
  1217   - Added "std" option and implemented support for nonstandard models.
  1218   - Added and implemented "finitize" option to improve the precision
  1219     of infinite datatypes based on a monotonicity analysis.
  1220   - Added support for quotient types.
  1221   - Added support for "specification" and "ax_specification"
  1222     constructs.
  1223   - Added support for local definitions (for "function" and
  1224     "termination" proofs).
  1225   - Added support for term postprocessors.
  1226   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1227   - Improved efficiency of "destroy_constrs" optimization.
  1228   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1229     record getters.
  1230   - Fixed soundness bug related to higher-order constructors.
  1231   - Fixed soundness bug when "full_descrs" is enabled.
  1232   - Improved precision of set constructs.
  1233   - Added "atoms" option.
  1234   - Added cache to speed up repeated Kodkod invocations on the same
  1235     problems.
  1236   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1237     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1238     "SAT4J_Light".  INCOMPATIBILITY.
  1239   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1240     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1241   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1242 
  1243 * Method "induct" now takes instantiations of the form t, where t is not
  1244   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1245   If this is not intended, t has to be enclosed in parentheses.
  1246   By default, the equalities generated by definitional instantiations
  1247   are pre-simplified, which may cause parameters of inductive cases
  1248   to disappear, or may even delete some of the inductive cases.
  1249   Use "induct (no_simp)" instead of "induct" to restore the old
  1250   behaviour. The (no_simp) option is also understood by the "cases"
  1251   and "nominal_induct" methods, which now perform pre-simplification, too.
  1252   INCOMPATIBILITY.
  1253 
  1254 
  1255 *** HOLCF ***
  1256 
  1257 * Variable names in lemmas generated by the domain package have
  1258 changed; the naming scheme is now consistent with the HOL datatype
  1259 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1260 
  1261 * The domain package no longer defines the function "foo_copy" for
  1262 recursive domain "foo".  The reach lemma is now stated directly in
  1263 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1264 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1265 
  1266 * Most definedness lemmas generated by the domain package (previously
  1267 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1268 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1269 Proofs that used definedness lemmas as intro rules may break,
  1270 potential INCOMPATIBILITY.
  1271 
  1272 * Induction and casedist rules generated by the domain package now
  1273 declare proper case_names (one called "bottom", and one named for each
  1274 constructor).  INCOMPATIBILITY.
  1275 
  1276 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1277 rules are generated for each domain, INCOMPATIBILITY.
  1278 
  1279   foo_bar.reach       ~> foo.reach  bar.reach
  1280   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1281 
  1282 * Some lemmas generated by the domain package have been renamed for
  1283 consistency with the datatype package, INCOMPATIBILITY.
  1284 
  1285   foo.ind        ~> foo.induct
  1286   foo.finite_ind ~> foo.finite_induct
  1287   foo.coind      ~> foo.coinduct
  1288   foo.casedist   ~> foo.exhaust
  1289   foo.exhaust    ~> foo.nchotomy
  1290 
  1291 * For consistency with other definition packages, the fixrec package
  1292 now generates qualified theorem names, INCOMPATIBILITY.
  1293 
  1294   foo_simps  ~> foo.simps
  1295   foo_unfold ~> foo.unfold
  1296   foo_induct ~> foo.induct
  1297 
  1298 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1299 method and internal fixrec proofs now use the default simpset instead.
  1300 INCOMPATIBILITY.
  1301 
  1302 * The "contlub" predicate has been removed.  Proof scripts should use
  1303 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1304 
  1305 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1306 
  1307 * The constants cpair, cfst, and csnd have been removed in favor of
  1308 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1309 
  1310 
  1311 *** ML ***
  1312 
  1313 * Antiquotations for basic formal entities:
  1314 
  1315     @{class NAME}         -- type class
  1316     @{class_syntax NAME}  -- syntax representation of the above
  1317 
  1318     @{type_name NAME}     -- logical type
  1319     @{type_abbrev NAME}   -- type abbreviation
  1320     @{nonterminal NAME}   -- type of concrete syntactic category
  1321     @{type_syntax NAME}   -- syntax representation of any of the above
  1322 
  1323     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1324     @{const_abbrev NAME}  -- abbreviated constant
  1325     @{const_syntax NAME}  -- syntax representation of any of the above
  1326 
  1327 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1328 syntax constant (cf. 'syntax' command).
  1329 
  1330 * Antiquotation @{make_string} inlines a function to print arbitrary
  1331 values similar to the ML toplevel.  The result is compiler dependent
  1332 and may fall back on "?" in certain situations.
  1333 
  1334 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1335 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1336 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1337 not work with the asynchronous Isar document model.
  1338 
  1339 * Configuration options now admit dynamic default values, depending on
  1340 the context or even global references.
  1341 
  1342 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1343 uses an efficient external library if available (for Poly/ML).
  1344 
  1345 * Renamed some important ML structures, while keeping the old names
  1346 for some time as aliases within the structure Legacy:
  1347 
  1348   OuterKeyword  ~>  Keyword
  1349   OuterLex      ~>  Token
  1350   OuterParse    ~>  Parse
  1351   OuterSyntax   ~>  Outer_Syntax
  1352   PrintMode     ~>  Print_Mode
  1353   SpecParse     ~>  Parse_Spec
  1354   ThyInfo       ~>  Thy_Info
  1355   ThyLoad       ~>  Thy_Load
  1356   ThyOutput     ~>  Thy_Output
  1357   TypeInfer     ~>  Type_Infer
  1358 
  1359 Note that "open Legacy" simplifies porting of sources, but forgetting
  1360 to remove it again will complicate porting again in the future.
  1361 
  1362 * Most operations that refer to a global context are named
  1363 accordingly, e.g. Simplifier.global_context or
  1364 ProofContext.init_global.  There are some situations where a global
  1365 context actually works, but under normal circumstances one needs to
  1366 pass the proper local context through the code!
  1367 
  1368 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1369 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1370 Pretty.pp argument to merge, which is absent in the standard
  1371 Theory_Data version.
  1372 
  1373 * Sorts.certify_sort and derived "cert" operations for types and terms
  1374 no longer minimize sorts.  Thus certification at the boundary of the
  1375 inference kernel becomes invariant under addition of class relations,
  1376 which is an important monotonicity principle.  Sorts are now minimized
  1377 in the syntax layer only, at the boundary between the end-user and the
  1378 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1379 explicitly in rare situations.
  1380 
  1381 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1382 emphasize that this is in no way a standard operation.
  1383 INCOMPATIBILITY.
  1384 
  1385 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1386 usual for resolution.  Rare INCOMPATIBILITY.
  1387 
  1388 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1389 to emphasize that these only work in a global situation (which is
  1390 quite rare).
  1391 
  1392 * Curried take and drop in library.ML; negative length is interpreted
  1393 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1394 
  1395 * Proof terms: type substitutions on proof constants now use canonical
  1396 order of type variables.  INCOMPATIBILITY for tools working with proof
  1397 terms.
  1398 
  1399 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1400 may no longer carry premises.  User-level specifications are
  1401 transformed accordingly by Thm.add_axiom/add_def.
  1402 
  1403 
  1404 *** System ***
  1405 
  1406 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1407 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1408 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1409 
  1410 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1411 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1412 respectively.
  1413 
  1414 * Old lib/scripts/polyml-platform is superseded by the
  1415 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1416 variant, even on a 64 bit machine.  The following example setting
  1417 prefers 64 bit if available:
  1418 
  1419   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1420 
  1421 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1422 Isabelle/Scala layer for advanced prover interaction and integration.
  1423 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1424 component.
  1425 
  1426 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1427 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1428 similar to the default assignment of the document preparation system
  1429 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1430 provides some operations for direct access to the font without asking
  1431 the user for manual installation.
  1432 
  1433 
  1434 
  1435 New in Isabelle2009-1 (December 2009)
  1436 -------------------------------------
  1437 
  1438 *** General ***
  1439 
  1440 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1441 one backslash should be used, even in ML sources.
  1442 
  1443 
  1444 *** Pure ***
  1445 
  1446 * Locale interpretation propagates mixins along the locale hierarchy.
  1447 The currently only available mixins are the equations used to map
  1448 local definitions to terms of the target domain of an interpretation.
  1449 
  1450 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1451 loc" to print all interpretations of locale "loc" in the theory.
  1452 Interpretations in proofs are not shown.
  1453 
  1454 * Thoroughly revised locales tutorial.  New section on conditional
  1455 interpretation.
  1456 
  1457 * On instantiation of classes, remaining undefined class parameters
  1458 are formally declared.  INCOMPATIBILITY.
  1459 
  1460 
  1461 *** Document preparation ***
  1462 
  1463 * New generalized style concept for printing terms: @{foo (style) ...}
  1464 instead of @{foo_style style ...}  (old form is still retained for
  1465 backward compatibility).  Styles can be also applied for
  1466 antiquotations prop, term_type and typeof.
  1467 
  1468 
  1469 *** HOL ***
  1470 
  1471 * New proof method "smt" for a combination of first-order logic with
  1472 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1473 fixed-size bitvectors; there is also basic support for higher-order
  1474 features (esp. lambda abstractions).  It is an incomplete decision
  1475 procedure based on external SMT solvers using the oracle mechanism;
  1476 for the SMT solver Z3, this method is proof-producing.  Certificates
  1477 are provided to avoid calling the external solvers solely for
  1478 re-checking proofs.  Due to a remote SMT service there is no need for
  1479 installing SMT solvers locally.  See src/HOL/SMT.
  1480 
  1481 * New commands to load and prove verification conditions generated by
  1482 the Boogie program verifier or derived systems (e.g. the Verifying C
  1483 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1484 
  1485 * New counterexample generator tool 'nitpick' based on the Kodkod
  1486 relational model finder.  See src/HOL/Tools/Nitpick and
  1487 src/HOL/Nitpick_Examples.
  1488 
  1489 * New commands 'code_pred' and 'values' to invoke the predicate
  1490 compiler and to enumerate values of inductive predicates.
  1491 
  1492 * A tabled implementation of the reflexive transitive closure.
  1493 
  1494 * New implementation of quickcheck uses generic code generator;
  1495 default generators are provided for all suitable HOL types, records
  1496 and datatypes.  Old quickcheck can be re-activated importing theory
  1497 Library/SML_Quickcheck.
  1498 
  1499 * New testing tool Mirabelle for automated proof tools.  Applies
  1500 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1501 every proof step in a theory.  To be used in batch mode via the
  1502 "mirabelle" utility.
  1503 
  1504 * New proof method "sos" (sum of squares) for nonlinear real
  1505 arithmetic (originally due to John Harison). It requires theory
  1506 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1507 works well in practice on quantifier-free real arithmetic with +, -,
  1508 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1509 inequalities between polynomials.  It makes use of external
  1510 semidefinite programming solvers.  Method "sos" generates a
  1511 certificate that can be pasted into the proof thus avoiding the need
  1512 to call an external tool every time the proof is checked.  See
  1513 src/HOL/Library/Sum_Of_Squares.
  1514 
  1515 * New method "linarith" invokes existing linear arithmetic decision
  1516 procedure only.
  1517 
  1518 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1519 
  1520 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1521 Causes full type information to be output to the ATPs.  This slows
  1522 ATPs down considerably but eliminates a source of unsound "proofs"
  1523 that fail later.
  1524 
  1525 * New method "metisFT": A version of metis that uses full type
  1526 information in order to avoid failures of proof reconstruction.
  1527 
  1528 * New evaluator "approximate" approximates an real valued term using
  1529 the same method as the approximation method.
  1530 
  1531 * Method "approximate" now supports arithmetic expressions as
  1532 boundaries of intervals and implements interval splitting and Taylor
  1533 series expansion.
  1534 
  1535 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1536 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1537 
  1538 * New theory SupInf of the supremum and infimum operators for sets of
  1539 reals.
  1540 
  1541 * New theory Probability, which contains a development of measure
  1542 theory, eventually leading to Lebesgue integration and probability.
  1543 
  1544 * Extended Multivariate Analysis to include derivation and Brouwer's
  1545 fixpoint theorem.
  1546 
  1547 * Reorganization of number theory, INCOMPATIBILITY:
  1548   - new number theory development for nat and int, in theories Divides
  1549     and GCD as well as in new session Number_Theory
  1550   - some constants and facts now suffixed with _nat and _int
  1551     accordingly
  1552   - former session NumberTheory now named Old_Number_Theory, including
  1553     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1554   - moved theory Pocklington from src/HOL/Library to
  1555     src/HOL/Old_Number_Theory
  1556 
  1557 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1558 lcm of finite and infinite sets. It is shown that they form a complete
  1559 lattice.
  1560 
  1561 * Class semiring_div requires superclass no_zero_divisors and proof of
  1562 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1563 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1564 generalized to class semiring_div, subsuming former theorems
  1565 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1566 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1567 INCOMPATIBILITY.
  1568 
  1569 * Refinements to lattice classes and sets:
  1570   - less default intro/elim rules in locale variant, more default
  1571     intro/elim rules in class variant: more uniformity
  1572   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1573     le_inf_iff
  1574   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1575     sup_aci)
  1576   - renamed ACI to inf_sup_aci
  1577   - new class "boolean_algebra"
  1578   - class "complete_lattice" moved to separate theory
  1579     "Complete_Lattice"; corresponding constants (and abbreviations)
  1580     renamed and with authentic syntax:
  1581     Set.Inf ~>    Complete_Lattice.Inf
  1582     Set.Sup ~>    Complete_Lattice.Sup
  1583     Set.INFI ~>   Complete_Lattice.INFI
  1584     Set.SUPR ~>   Complete_Lattice.SUPR
  1585     Set.Inter ~>  Complete_Lattice.Inter
  1586     Set.Union ~>  Complete_Lattice.Union
  1587     Set.INTER ~>  Complete_Lattice.INTER
  1588     Set.UNION ~>  Complete_Lattice.UNION
  1589   - authentic syntax for
  1590     Set.Pow
  1591     Set.image
  1592   - mere abbreviations:
  1593     Set.empty               (for bot)
  1594     Set.UNIV                (for top)
  1595     Set.inter               (for inf, formerly Set.Int)
  1596     Set.union               (for sup, formerly Set.Un)
  1597     Complete_Lattice.Inter  (for Inf)
  1598     Complete_Lattice.Union  (for Sup)
  1599     Complete_Lattice.INTER  (for INFI)
  1600     Complete_Lattice.UNION  (for SUPR)
  1601   - object-logic definitions as far as appropriate
  1602 
  1603 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1604 Un_subset_iff are explicitly deleted as default simp rules; then also
  1605 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1606 deleted to achieve the desired effect.
  1607 
  1608 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1609 rules by default any longer; the same applies to min_max.inf_absorb1
  1610 etc.  INCOMPATIBILITY.
  1611 
  1612 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1613 pred_set_conv by default.  INCOMPATIBILITY.
  1614 
  1615 * Power operations on relations and functions are now one dedicated
  1616 constant "compow" with infix syntax "^^".  Power operation on
  1617 multiplicative monoids retains syntax "^" and is now defined generic
  1618 in class power.  INCOMPATIBILITY.
  1619 
  1620 * Relation composition "R O S" now has a more standard argument order:
  1621 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1622 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1623 break, since the O_assoc rule was not rewritten like this.  Fix using
  1624 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1625 
  1626 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1627 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1628 INCOMPATIBILITY.
  1629 
  1630 * Most rules produced by inductive and datatype package have mandatory
  1631 prefixes.  INCOMPATIBILITY.
  1632 
  1633 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1634 the attribute of the same name.  Each of the theorems in the list
  1635 DERIV_intros assumes composition with an additional function and
  1636 matches a variable to the derivative, which has to be solved by the
  1637 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1638 of most elementary terms.  Former Maclauren.DERIV_tac and
  1639 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1640 INCOMPATIBILITY.
  1641 
  1642 * Code generator attributes follow the usual underscore convention:
  1643     code_unfold     replaces    code unfold
  1644     code_post       replaces    code post
  1645     etc.
  1646   INCOMPATIBILITY.
  1647 
  1648 * Renamed methods:
  1649     sizechange -> size_change
  1650     induct_scheme -> induction_schema
  1651   INCOMPATIBILITY.
  1652 
  1653 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1654 INCOMPATIBILITY, use "undefined" directly.
  1655 
  1656 * Renamed theorems:
  1657     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1658     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1659     Suc_plus1 -> Suc_eq_plus1
  1660     *anti_sym -> *antisym*
  1661     vector_less_eq_def -> vector_le_def
  1662   INCOMPATIBILITY.
  1663 
  1664 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1665 INCOMPATIBILITY.
  1666 
  1667 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1668 INCOMPATIBILITY.
  1669 
  1670 
  1671 *** HOLCF ***
  1672 
  1673 * Theory Representable defines a class "rep" of domains that are
  1674 representable (via an ep-pair) in the universal domain type "udom".
  1675 Instances are provided for all type constructors defined in HOLCF.
  1676 
  1677 * The 'new_domain' command is a purely definitional version of the
  1678 domain package, for representable domains.  Syntax is identical to the
  1679 old domain package.  The 'new_domain' package also supports indirect
  1680 recursion using previously-defined type constructors.  See
  1681 src/HOLCF/ex/New_Domain.thy for examples.
  1682 
  1683 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1684 on the left-hand side of an equation, and then performs
  1685 simplification.  Rewriting is done using rules declared with the
  1686 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1687 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1688 
  1689 * The pattern-match compiler in 'fixrec' can now handle constructors
  1690 with HOL function types.  Pattern-match combinators for the Pair
  1691 constructor are pre-configured.
  1692 
  1693 * The 'fixrec' package now produces better fixed-point induction rules
  1694 for mutually-recursive definitions:  Induction rules have conclusions
  1695 of the form "P foo bar" instead of "P <foo, bar>".
  1696 
  1697 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1698 been renamed to "below".  The name "below" now replaces "less" in many
  1699 theorem names.  (Legacy theorem names using "less" are still supported
  1700 as well.)
  1701 
  1702 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1703 patterns can be used to generate strictness rules, or to make
  1704 functions more strict (much like the bang-patterns supported by the
  1705 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1706 examples.
  1707 
  1708 
  1709 *** ML ***
  1710 
  1711 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1712 errors and run-time exceptions, including detailed source positions.
  1713 
  1714 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1715 identified entries, with some additional information such as source
  1716 position, logical grouping etc.
  1717 
  1718 * Theory and context data is now introduced by the simplified and
  1719 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1720 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1721 copy operation) is still available for some time.
  1722 
  1723 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1724 provides a high-level programming interface to synchronized state
  1725 variables with atomic update.  This works via pure function
  1726 application within a critical section -- its runtime should be as
  1727 short as possible; beware of deadlocks if critical code is nested,
  1728 either directly or indirectly via other synchronized variables!
  1729 
  1730 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1731 wraps raw ML references, explicitly indicating their non-thread-safe
  1732 behaviour.  The Isar toplevel keeps this structure open, to
  1733 accommodate Proof General as well as quick and dirty interactive
  1734 experiments with references.
  1735 
  1736 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1737 parallel tactical reasoning.
  1738 
  1739 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1740 are similar to SUBPROOF, but are slightly more flexible: only the
  1741 specified parts of the subgoal are imported into the context, and the
  1742 body tactic may introduce new subgoals and schematic variables.
  1743 
  1744 * Old tactical METAHYPS, which does not observe the proof context, has
  1745 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1746 or Subgoal.FOCUS etc.
  1747 
  1748 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1749 functors have their own ML name space there is no point to mark them
  1750 separately.)  Minor INCOMPATIBILITY.
  1751 
  1752 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1753 
  1754 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1755 INCOMPATIBILITY.
  1756 
  1757 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1758 mode, which avoids critical setmp.
  1759 
  1760 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1761 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1762 Attrib/Method.setup introduced in Isabelle2009.
  1763 
  1764 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1765 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1766 last resort.  INCOMPATIBILITY.
  1767 
  1768 * Display.pretty_thm now requires a proper context (cf. former
  1769 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1770 or even Display.pretty_thm_without_context as last resort.
  1771 INCOMPATIBILITY.
  1772 
  1773 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1774 Syntax.pretty_typ/term directly, preferably with proper context
  1775 instead of global theory.
  1776 
  1777 
  1778 *** System ***
  1779 
  1780 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1781 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1782 usedir option -q.
  1783 
  1784 * Support for additional "Isabelle components" via etc/components, see
  1785 also the system manual.
  1786 
  1787 * The isabelle makeall tool now operates on all components with
  1788 IsaMakefile, not just hardwired "logics".
  1789 
  1790 * Removed "compress" option from isabelle-process and isabelle usedir;
  1791 this is always enabled.
  1792 
  1793 * Discontinued support for Poly/ML 4.x versions.
  1794 
  1795 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  1796 on a given logic image.  This requires the lighttpd webserver and is
  1797 currently supported on Linux only.
  1798 
  1799 
  1800 
  1801 New in Isabelle2009 (April 2009)
  1802 --------------------------------
  1803 
  1804 *** General ***
  1805 
  1806 * Simplified main Isabelle executables, with less surprises on
  1807 case-insensitive file-systems (such as Mac OS).
  1808 
  1809   - The main Isabelle tool wrapper is now called "isabelle" instead of
  1810     "isatool."
  1811 
  1812   - The former "isabelle" alias for "isabelle-process" has been
  1813     removed (should rarely occur to regular users).
  1814 
  1815   - The former "isabelle-interface" and its alias "Isabelle" have been
  1816     removed (interfaces are now regular Isabelle tools).
  1817 
  1818 Within scripts and make files, the Isabelle environment variables
  1819 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  1820 respectively.  (The latter are still available as legacy feature.)
  1821 
  1822 The old isabelle-interface wrapper could react in confusing ways if
  1823 the interface was uninstalled or changed otherwise.  Individual
  1824 interface tool configuration is now more explicit, see also the
  1825 Isabelle system manual.  In particular, Proof General is now available
  1826 via "isabelle emacs".
  1827 
  1828 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  1829 purge installed copies of Isabelle executables and re-run "isabelle
  1830 install -p ...", or use symlinks.
  1831 
  1832 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  1833 old ~/isabelle, which was slightly non-standard and apt to cause
  1834 surprises on case-insensitive file-systems (such as Mac OS).
  1835 
  1836 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  1837 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  1838 care is required when using older releases of Isabelle.  Note that
  1839 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  1840 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  1841 
  1842 * Proofs of fully specified statements are run in parallel on
  1843 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  1844 a regular 4-core machine, if the initial heap space is made reasonably
  1845 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  1846 
  1847 * The main reference manuals ("isar-ref", "implementation", and
  1848 "system") have been updated and extended.  Formally checked references
  1849 as hyperlinks are now available uniformly.
  1850 
  1851 
  1852 *** Pure ***
  1853 
  1854 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  1855 respects.  The most important changes are listed below.  See the
  1856 Tutorial on Locales ("locales" manual) for details.
  1857 
  1858 - In locale expressions, instantiation replaces renaming.  Parameters
  1859 must be declared in a for clause.  To aid compatibility with previous
  1860 parameter inheritance, in locale declarations, parameters that are not
  1861 'touched' (instantiation position "_" or omitted) are implicitly added
  1862 with their syntax at the beginning of the for clause.
  1863 
  1864 - Syntax from abbreviations and definitions in locales is available in
  1865 locale expressions and context elements.  The latter is particularly
  1866 useful in locale declarations.
  1867 
  1868 - More flexible mechanisms to qualify names generated by locale
  1869 expressions.  Qualifiers (prefixes) may be specified in locale
  1870 expressions, and can be marked as mandatory (syntax: "name!:") or
  1871 optional (syntax "name?:").  The default depends for plain "name:"
  1872 depends on the situation where a locale expression is used: in
  1873 commands 'locale' and 'sublocale' prefixes are optional, in
  1874 'interpretation' and 'interpret' prefixes are mandatory.  The old
  1875 implicit qualifiers derived from the parameter names of a locale are
  1876 no longer generated.
  1877 
  1878 - Command "sublocale l < e" replaces "interpretation l < e".  The
  1879 instantiation clause in "interpretation" and "interpret" (square
  1880 brackets) is no longer available.  Use locale expressions.
  1881 
  1882 - When converting proof scripts, mandatory qualifiers in
  1883 'interpretation' and 'interpret' should be retained by default, even
  1884 if this is an INCOMPATIBILITY compared to former behavior.  In the
  1885 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  1886 in locale expressions range over a single locale instance only.
  1887 
  1888 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  1889 In existing theorem specifications replace the includes element by the
  1890 respective context elements of the included locale, omitting those
  1891 that are already present in the theorem specification.  Multiple
  1892 assume elements of a locale should be replaced by a single one
  1893 involving the locale predicate.  In the proof body, declarations (most
  1894 notably theorems) may be regained by interpreting the respective
  1895 locales in the proof context as required (command "interpret").
  1896 
  1897 If using "includes" in replacement of a target solely because the
  1898 parameter types in the theorem are not as general as in the target,
  1899 consider declaring a new locale with additional type constraints on
  1900 the parameters (context element "constrains").
  1901 
  1902 - Discontinued "locale (open)".  INCOMPATIBILITY.
  1903 
  1904 - Locale interpretation commands no longer attempt to simplify goal.
  1905 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  1906 methods intro_locales and unfold_locales to clarify.
  1907 
  1908 - Locale interpretation commands no longer accept interpretation
  1909 attributes.  INCOMPATIBILITY.
  1910 
  1911 * Class declaration: so-called "base sort" must not be given in import
  1912 list any longer, but is inferred from the specification.  Particularly
  1913 in HOL, write
  1914 
  1915     class foo = ...
  1916 
  1917 instead of
  1918 
  1919     class foo = type + ...
  1920 
  1921 * Class target: global versions of theorems stemming do not carry a
  1922 parameter prefix any longer.  INCOMPATIBILITY.
  1923 
  1924 * Class 'instance' command no longer accepts attached definitions.
  1925 INCOMPATIBILITY, use proper 'instantiation' target instead.
  1926 
  1927 * Recovered hiding of consts, which was accidentally broken in
  1928 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  1929 makes c inaccessible; consider using ``hide (open) const c'' instead.
  1930 
  1931 * Slightly more coherent Pure syntax, with updated documentation in
  1932 isar-ref manual.  Removed locales meta_term_syntax and
  1933 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  1934 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  1935 directly in regular applications.
  1936 
  1937 * There is a new syntactic category "float_const" for signed decimal
  1938 fractions (e.g. 123.45 or -123.45).
  1939 
  1940 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  1941 interface with 'setup' command instead.
  1942 
  1943 * Command 'local_setup' is similar to 'setup', but operates on a local
  1944 theory context.
  1945 
  1946 * The 'axiomatization' command now only works within a global theory
  1947 context.  INCOMPATIBILITY.
  1948 
  1949 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  1950 hypotheses.  Sorts required in the course of reasoning need to be
  1951 covered by the constraints in the initial statement, completed by the
  1952 type instance information of the background theory.  Non-trivial sort
  1953 hypotheses, which rarely occur in practice, may be specified via
  1954 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  1955 
  1956   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  1957 
  1958 The result contains an implicit sort hypotheses as before --
  1959 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  1960 normalization.
  1961 
  1962 * Generalized Isar history, with support for linear undo, direct state
  1963 addressing etc.
  1964 
  1965 * Changed defaults for unify configuration options:
  1966 
  1967   unify_trace_bound = 50 (formerly 25)
  1968   unify_search_bound = 60 (formerly 30)
  1969 
  1970 * Different bookkeeping for code equations (INCOMPATIBILITY):
  1971 
  1972   a) On theory merge, the last set of code equations for a particular
  1973      constant is taken (in accordance with the policy applied by other
  1974      parts of the code generator framework).
  1975 
  1976   b) Code equations stemming from explicit declarations (e.g. code
  1977      attribute) gain priority over default code equations stemming
  1978      from definition, primrec, fun etc.
  1979 
  1980 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  1981 
  1982 * Unified theorem tables for both code generators.  Thus [code
  1983 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  1984 
  1985 * Command 'find_consts' searches for constants based on type and name
  1986 patterns, e.g.
  1987 
  1988     find_consts "_ => bool"
  1989 
  1990 By default, matching is against subtypes, but it may be restricted to
  1991 the whole type.  Searching by name is possible.  Multiple queries are
  1992 conjunctive and queries may be negated by prefixing them with a
  1993 hyphen:
  1994 
  1995     find_consts strict: "_ => bool" name: "Int" -"int => int"
  1996 
  1997 * New 'find_theorems' criterion "solves" matches theorems that
  1998 directly solve the current goal (modulo higher-order unification).
  1999 
  2000 * Auto solve feature for main theorem statements: whenever a new goal
  2001 is stated, "find_theorems solves" is called; any theorems that could
  2002 solve the lemma directly are listed as part of the goal state.
  2003 Cf. associated options in Proof General Isabelle settings menu,
  2004 enabled by default, with reasonable timeout for pathological cases of
  2005 higher-order unification.
  2006 
  2007 
  2008 *** Document preparation ***
  2009 
  2010 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2011 demanding keyword 'by' and supporting the full method expression
  2012 syntax just like the Isar command 'by'.
  2013 
  2014 
  2015 *** HOL ***
  2016 
  2017 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2018 points Main and Complex_Main remain as before.
  2019 
  2020 * Logic image HOL-Plain provides a minimal HOL with the most important
  2021 tools available (inductive, datatype, primrec, ...).  This facilitates
  2022 experimentation and tool development.  Note that user applications
  2023 (and library theories) should never refer to anything below theory
  2024 Main, as before.
  2025 
  2026 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2027 experimentation due to shorter build times.
  2028 
  2029 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2030 were previously part of former HOL-Complex.  Entry point Hyperreal
  2031 remains valid, but theories formerly using Complex_Main should now use
  2032 new entry point Hypercomplex.
  2033 
  2034 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2035 Posix processes.  Avoids potentially expensive forking of the ML
  2036 process.  New thread-based implementation also works on non-Unix
  2037 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2038 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2039 commands are covered in the isar-ref manual.
  2040 
  2041 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2042 sledgehammer without local ATP installation (Vampire etc.). Other
  2043 provers may be included via suitable ML wrappers, see also
  2044 src/HOL/ATP_Linkup.thy.
  2045 
  2046 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2047 menu.
  2048 
  2049 * The metis method no longer fails because the theorem is too trivial
  2050 (contains the empty clause).
  2051 
  2052 * The metis method now fails in the usual manner, rather than raising
  2053 an exception, if it determines that it cannot prove the theorem.
  2054 
  2055 * Method "coherent" implements a prover for coherent logic (see also
  2056 src/Tools/coherent.ML).
  2057 
  2058 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2059 "undefined" is the right choice to replace "arbitrary", though
  2060 logically there is no difference.  INCOMPATIBILITY.
  2061 
  2062 * Command "value" now integrates different evaluation mechanisms.  The
  2063 result of the first successful evaluation mechanism is printed.  In
  2064 square brackets a particular named evaluation mechanisms may be
  2065 specified (currently, [SML], [code] or [nbe]).  See further
  2066 src/HOL/ex/Eval_Examples.thy.
  2067 
  2068 * Normalization by evaluation now allows non-leftlinear equations.
  2069 Declare with attribute [code nbe].
  2070 
  2071 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2072 as the structured Isar versions "cases" and "induct", cf. the
  2073 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2074 are now presented as a list of individual projections
  2075 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2076 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2077 rare situations a different rule is selected --- notably nested tuple
  2078 elimination instead of former prod.exhaust: use explicit (case_tac t
  2079 rule: prod.exhaust) here.
  2080 
  2081 * Attributes "cases", "induct", "coinduct" support "del" option.
  2082 
  2083 * Removed fact "case_split_thm", which duplicates "case_split".
  2084 
  2085 * The option datatype has been moved to a new theory Option.  Renamed
  2086 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2087 
  2088 * New predicate "strict_mono" classifies strict functions on partial
  2089 orders.  With strict functions on linear orders, reasoning about
  2090 (in)equalities is facilitated by theorems "strict_mono_eq",
  2091 "strict_mono_less_eq" and "strict_mono_less".
  2092 
  2093 * Some set operations are now proper qualified constants with
  2094 authentic syntax.  INCOMPATIBILITY:
  2095 
  2096     op Int ~>   Set.Int
  2097     op Un ~>    Set.Un
  2098     INTER ~>    Set.INTER
  2099     UNION ~>    Set.UNION
  2100     Inter ~>    Set.Inter
  2101     Union ~>    Set.Union
  2102     {} ~>       Set.empty
  2103     UNIV ~>     Set.UNIV
  2104 
  2105 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2106 theory Set.
  2107 
  2108 * Auxiliary class "itself" has disappeared -- classes without any
  2109 parameter are treated as expected by the 'class' command.
  2110 
  2111 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2112 
  2113 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2114 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2115 
  2116 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2117 method "approximation".  It proves formulas on real values by using
  2118 interval arithmetic.  In the formulas are also the transcendental
  2119 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2120 allowed. For examples see
  2121 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2122 
  2123 * Theory "Reflection" now resides in HOL/Library.
  2124 
  2125 * Entry point to Word library now simply named "Word".
  2126 INCOMPATIBILITY.
  2127 
  2128 * Made source layout more coherent with logical distribution
  2129 structure:
  2130 
  2131     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2132     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2133     src/HOL/Library/GCD.thy ~> src/HOL/
  2134     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2135     src/HOL/Library/Parity.thy ~> src/HOL/
  2136     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2137     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2138     src/HOL/Real/Lubs.thy ~> src/HOL/
  2139     src/HOL/Real/PReal.thy ~> src/HOL/
  2140     src/HOL/Real/Rational.thy ~> src/HOL/
  2141     src/HOL/Real/RComplete.thy ~> src/HOL/
  2142     src/HOL/Real/RealDef.thy ~> src/HOL/
  2143     src/HOL/Real/RealPow.thy ~> src/HOL/
  2144     src/HOL/Real/Real.thy ~> src/HOL/
  2145     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2146     src/HOL/Complex/Complex.thy ~> src/HOL/
  2147     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2148     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2149     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2150     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2151     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2152     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2153     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2154     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2155     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2156     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2157     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2158     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2159     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2160     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2161     src/HOL/Real/Float ~> src/HOL/Library/
  2162     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2163     src/HOL/Real/RealVector.thy ~> src/HOL/
  2164 
  2165     src/HOL/arith_data.ML ~> src/HOL/Tools
  2166     src/HOL/hologic.ML ~> src/HOL/Tools
  2167     src/HOL/simpdata.ML ~> src/HOL/Tools
  2168     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2169     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2170     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2171     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2172     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2173     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2174     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2175 
  2176     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2177     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2178     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2179     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2180     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2181     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2182 
  2183 * If methods "eval" and "evaluation" encounter a structured proof
  2184 state with !!/==>, only the conclusion is evaluated to True (if
  2185 possible), avoiding strange error messages.
  2186 
  2187 * Method "sizechange" automates termination proofs using (a
  2188 modification of) the size-change principle.  Requires SAT solver.  See
  2189 src/HOL/ex/Termination.thy for examples.
  2190 
  2191 * Simplifier: simproc for let expressions now unfolds if bound
  2192 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2193 
  2194 * Method "arith": Linear arithmetic now ignores all inequalities when
  2195 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2196 
  2197 * New attribute "arith" for facts that should always be used
  2198 automatically by arithmetic. It is intended to be used locally in
  2199 proofs, e.g.
  2200 
  2201   assumes [arith]: "x > 0"
  2202 
  2203 Global usage is discouraged because of possible performance impact.
  2204 
  2205 * New classes "top" and "bot" with corresponding operations "top" and
  2206 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2207 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2208 
  2209 * Changed definition lemma "less_fun_def" in order to provide an
  2210 instance for preorders on functions; use lemma "less_le" instead.
  2211 INCOMPATIBILITY.
  2212 
  2213 * Theory Orderings: class "wellorder" moved here, with explicit
  2214 induction rule "less_induct" as assumption.  For instantiation of
  2215 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2216 INCOMPATIBILITY.
  2217 
  2218 * Theory Orderings: added class "preorder" as superclass of "order".
  2219 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2220 etc. slightly changed.  Some theorems named order_class.* now named
  2221 preorder_class.*.
  2222 
  2223 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2224 "diag" to "Id_on".
  2225 
  2226 * Theory Finite_Set: added a new fold combinator of type
  2227 
  2228   ('a => 'b => 'b) => 'b => 'a set => 'b
  2229 
  2230 Occasionally this is more convenient than the old fold combinator
  2231 which is now defined in terms of the new one and renamed to
  2232 fold_image.
  2233 
  2234 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2235 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2236 extended with further lemmas!).  At the moment both still exist but
  2237 the former will disappear at some point.
  2238 
  2239 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2240 class recpower.  Type-specific simp rules for various recpower types
  2241 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2242 
  2243 rat_power_0    -> power_0
  2244 rat_power_Suc  -> power_Suc
  2245 realpow_0      -> power_0
  2246 realpow_Suc    -> power_Suc
  2247 complexpow_0   -> power_0
  2248 complexpow_Suc -> power_Suc
  2249 power_poly_0   -> power_0
  2250 power_poly_Suc -> power_Suc
  2251 
  2252 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2253 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2254 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2255 of lemmas from Divides has been generalized from nat to class
  2256 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2257 renames resulting from duplicate elimination:
  2258 
  2259     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2260     zero_dvd_iff ~>         dvd_0_left_iff
  2261     dvd_0 ~>                dvd_0_right
  2262     DIVISION_BY_ZERO_DIV ~> div_by_0
  2263     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2264     mult_div ~>             div_mult_self2_is_id
  2265     mult_mod ~>             mod_mult_self2_is_0
  2266 
  2267 * Theory IntDiv: removed many lemmas that are instances of class-based
  2268 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2269 rename old lemmas as follows:
  2270 
  2271 dvd_diff               -> nat_dvd_diff
  2272 dvd_zminus_iff         -> dvd_minus_iff
  2273 mod_add1_eq            -> mod_add_eq
  2274 mod_mult1_eq           -> mod_mult_right_eq
  2275 mod_mult1_eq'          -> mod_mult_left_eq
  2276 mod_mult_distrib_mod   -> mod_mult_eq
  2277 nat_mod_add_left_eq    -> mod_add_left_eq
  2278 nat_mod_add_right_eq   -> mod_add_right_eq
  2279 nat_mod_div_trivial    -> mod_div_trivial
  2280 nat_mod_mod_trivial    -> mod_mod_trivial
  2281 zdiv_zadd_self1        -> div_add_self1
  2282 zdiv_zadd_self2        -> div_add_self2
  2283 zdiv_zmult_self1       -> div_mult_self2_is_id
  2284 zdiv_zmult_self2       -> div_mult_self1_is_id
  2285 zdvd_triv_left         -> dvd_triv_left
  2286 zdvd_triv_right        -> dvd_triv_right
  2287 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2288 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2289 zmod_zadd_left_eq      -> mod_add_left_eq
  2290 zmod_zadd_right_eq     -> mod_add_right_eq
  2291 zmod_zadd_self1        -> mod_add_self1
  2292 zmod_zadd_self2        -> mod_add_self2
  2293 zmod_zadd1_eq          -> mod_add_eq
  2294 zmod_zdiff1_eq         -> mod_diff_eq
  2295 zmod_zdvd_zmod         -> mod_mod_cancel
  2296 zmod_zmod_cancel       -> mod_mod_cancel
  2297 zmod_zmult_self1       -> mod_mult_self2_is_0
  2298 zmod_zmult_self2       -> mod_mult_self1_is_0
  2299 zmod_1                 -> mod_by_1
  2300 zdiv_1                 -> div_by_1
  2301 zdvd_abs1              -> abs_dvd_iff
  2302 zdvd_abs2              -> dvd_abs_iff
  2303 zdvd_refl              -> dvd_refl
  2304 zdvd_trans             -> dvd_trans
  2305 zdvd_zadd              -> dvd_add
  2306 zdvd_zdiff             -> dvd_diff
  2307 zdvd_zminus_iff        -> dvd_minus_iff
  2308 zdvd_zminus2_iff       -> minus_dvd_iff
  2309 zdvd_zmultD            -> dvd_mult_right
  2310 zdvd_zmultD2           -> dvd_mult_left
  2311 zdvd_zmult_mono        -> mult_dvd_mono
  2312 zdvd_0_right           -> dvd_0_right
  2313 zdvd_0_left            -> dvd_0_left_iff
  2314 zdvd_1_left            -> one_dvd
  2315 zminus_dvd_iff         -> minus_dvd_iff
  2316 
  2317 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2318 
  2319 * The real numbers offer decimal input syntax: 12.34 is translated
  2320 into 1234/10^2. This translation is not reversed upon output.
  2321 
  2322 * Theory Library/Polynomial defines an abstract type 'a poly of
  2323 univariate polynomials with coefficients of type 'a.  In addition to
  2324 the standard ring operations, it also supports div and mod.  Code
  2325 generation is also supported, using list-style constructors.
  2326 
  2327 * Theory Library/Inner_Product defines a class of real_inner for real
  2328 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2329 => real.  Class real_inner is a subclass of real_normed_vector from
  2330 theory RealVector.
  2331 
  2332 * Theory Library/Product_Vector provides instances for the product
  2333 type 'a * 'b of several classes from RealVector and Inner_Product.
  2334 Definitions of addition, subtraction, scalar multiplication, norms,
  2335 and inner products are included.
  2336 
  2337 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2338 addition to the field operations, numerals and case syntax are also
  2339 supported.
  2340 
  2341 * Theory Library/Diagonalize provides constructive version of Cantor's
  2342 first diagonalization argument.
  2343 
  2344 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2345 zlcm (for int); carried together from various gcd/lcm developements in
  2346 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2347 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2348 may recover tupled syntax as follows:
  2349 
  2350     hide (open) const gcd
  2351     abbreviation gcd where
  2352       "gcd == (%(a, b). GCD.gcd a b)"
  2353     notation (output)
  2354       GCD.gcd ("gcd '(_, _')")
  2355 
  2356 The same works for lcm, zgcd, zlcm.
  2357 
  2358 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2359 instantiations for algebraic structures.  Removed some duplicate
  2360 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2361 
  2362 * ML antiquotation @{code} takes a constant as argument and generates
  2363 corresponding code in background and inserts name of the corresponding
  2364 resulting ML value/function/datatype constructor binding in place.
  2365 All occurrences of @{code} with a single ML block are generated
  2366 simultaneously.  Provides a generic and safe interface for
  2367 instrumentalizing code generation.  See
  2368 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2369 In future you ought to refrain from ad-hoc compiling generated SML
  2370 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2371 cannot refer to constants for which user-defined serializations are
  2372 set.  Refer to the corresponding ML counterpart directly in that
  2373 cases.
  2374 
  2375 * Command 'rep_datatype': instead of theorem names the command now
  2376 takes a list of terms denoting the constructors of the type to be
  2377 represented as datatype.  The characteristic theorems have to be
  2378 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2379 have disappeared in favour of existing ones:
  2380 
  2381     unit_induct                 ~> unit.induct
  2382     prod_induct                 ~> prod.induct
  2383     sum_induct                  ~> sum.induct
  2384     Suc_Suc_eq                  ~> nat.inject
  2385     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2386 
  2387 
  2388 *** HOL-Algebra ***
  2389 
  2390 * New locales for orders and lattices where the equivalence relation
  2391 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2392 locales use a record structure with field eq for the equivalence.
  2393 
  2394 * New theory of factorial domains.
  2395 
  2396 * Units_l_inv and Units_r_inv are now simp rules by default.
  2397 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2398 and/or r_inv will now also require deletion of these lemmas.
  2399 
  2400 * Renamed the following theorems, INCOMPATIBILITY:
  2401 
  2402 UpperD ~> Upper_memD
  2403 LowerD ~> Lower_memD
  2404 least_carrier ~> least_closed
  2405 greatest_carrier ~> greatest_closed
  2406 greatest_Lower_above ~> greatest_Lower_below
  2407 one_zero ~> carrier_one_zero
  2408 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2409 
  2410 
  2411 *** HOL-Nominal ***
  2412 
  2413 * Nominal datatypes can now contain type-variables.
  2414 
  2415 * Commands 'nominal_inductive' and 'equivariance' work with local
  2416 theory targets.
  2417 
  2418 * Nominal primrec can now works with local theory targets and its
  2419 specification syntax now conforms to the general format as seen in
  2420 'inductive' etc.
  2421 
  2422 * Method "perm_simp" honours the standard simplifier attributes
  2423 (no_asm), (no_asm_use) etc.
  2424 
  2425 * The new predicate #* is defined like freshness, except that on the
  2426 left hand side can be a set or list of atoms.
  2427 
  2428 * Experimental command 'nominal_inductive2' derives strong induction
  2429 principles for inductive definitions.  In contrast to
  2430 'nominal_inductive', which can only deal with a fixed number of
  2431 binders, it can deal with arbitrary expressions standing for sets of
  2432 atoms to be avoided.  The only inductive definition we have at the
  2433 moment that needs this generalisation is the typing rule for Lets in
  2434 the algorithm W:
  2435 
  2436  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2437  -----------------------------------------------------------------
  2438          Gamma |- Let x be t1 in t2 : T2
  2439 
  2440 In this rule one wants to avoid all the binders that are introduced by
  2441 "close Gamma T1".  We are looking for other examples where this
  2442 feature might be useful.  Please let us know.
  2443 
  2444 
  2445 *** HOLCF ***
  2446 
  2447 * Reimplemented the simplification procedure for proving continuity
  2448 subgoals.  The new simproc is extensible; users can declare additional
  2449 continuity introduction rules with the attribute [cont2cont].
  2450 
  2451 * The continuity simproc now uses a different introduction rule for
  2452 solving continuity subgoals on terms with lambda abstractions.  In
  2453 some rare cases the new simproc may fail to solve subgoals that the
  2454 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2455 Potential INCOMPATIBILITY.
  2456 
  2457 * Command 'fixrec': specification syntax now conforms to the general
  2458 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2459 examples.  INCOMPATIBILITY.
  2460 
  2461 
  2462 *** ZF ***
  2463 
  2464 * Proof of Zorn's Lemma for partial orders.
  2465 
  2466 
  2467 *** ML ***
  2468 
  2469 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2470 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2471 depends on multithreading, so timouts will not work before Poly/ML
  2472 5.2.1!
  2473 
  2474 * High-level support for concurrent ML programming, see
  2475 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2476 particularly convenient to organize independent functional
  2477 computations.  The concept of "synchronized variables" provides a
  2478 higher-order interface for components with shared state, avoiding the
  2479 delicate details of mutexes and condition variables.  (Requires
  2480 Poly/ML 5.2.1 or later.)
  2481 
  2482 * ML bindings produced via Isar commands are stored within the Isar
  2483 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2484 become thread-safe and work with undo as expected (concerning
  2485 top-level bindings, not side-effects on global references).
  2486 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2487 compiler at runtime; really global bindings need to be given outside a
  2488 theory.  (Requires Poly/ML 5.2 or later.)
  2489 
  2490 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2491 context.  Top-level ML bindings are stored within the proof context in
  2492 a purely sequential fashion, disregarding the nested proof structure.
  2493 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2494 proof.  (Requires Poly/ML 5.2 or later.)
  2495 
  2496 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2497 and Method.setup, as well as Isar commands 'attribute_setup' and
  2498 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2499 existing code accordingly, or use plain 'setup' together with old
  2500 Method.add_method.
  2501 
  2502 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2503 to 'a -> thm, while results are always tagged with an authentic oracle
  2504 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2505 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2506 accordingly.  Note that extra performance may be gained by producing
  2507 the cterm carefully, avoiding slow Thm.cterm_of.
  2508 
  2509 * Simplified interface for defining document antiquotations via
  2510 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2511 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2512 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2513 examples.
  2514 
  2515 * More systematic treatment of long names, abstract name bindings, and
  2516 name space operations.  Basic operations on qualified names have been
  2517 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2518 Long_Name.append.  Old type bstring has been mostly replaced by
  2519 abstract type binding (see structure Binding), which supports precise
  2520 qualification by packages and local theory targets, as well as proper
  2521 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2522 bstring values into Binding.name, or better pass through abstract
  2523 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2524 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2525 
  2526 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2527 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2528 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2529 
  2530 * Disposed old type and term read functions (Sign.read_def_typ,
  2531 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2532 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2533 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2534 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2535 resort for legacy applications.
  2536 
  2537 * Disposed old declarations, tactics, tactic combinators that refer to
  2538 the simpset or claset of an implicit theory (such as Addsimps,
  2539 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2540 embedded ML text, or local_simpset_of with a proper context passed as
  2541 explicit runtime argument.
  2542 
  2543 * Rules and tactics that read instantiations (read_instantiate,
  2544 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2545 context, which is required for parsing and type-checking.  Moreover,
  2546 the variables are specified as plain indexnames, not string encodings
  2547 thereof.  INCOMPATIBILITY.
  2548 
  2549 * Generic Toplevel.add_hook interface allows to analyze the result of
  2550 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2551 for theorem dependency output of transactions resulting in a new
  2552 theory state.
  2553 
  2554 * ML antiquotations: block-structured compilation context indicated by
  2555 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2556 
  2557   @{binding name}                         - basic name binding
  2558   @{let ?pat = term}                      - term abbreviation (HO matching)
  2559   @{note name = fact}                     - fact abbreviation
  2560   @{thm fact}                             - singleton fact (with attributes)
  2561   @{thms fact}                            - general fact (with attributes)
  2562   @{lemma prop by method}                 - singleton goal
  2563   @{lemma prop by meth1 meth2}            - singleton goal
  2564   @{lemma prop1 ... propN by method}      - general goal
  2565   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2566   @{lemma (open) ...}                     - open derivation
  2567 
  2568 
  2569 *** System ***
  2570 
  2571 * The Isabelle "emacs" tool provides a specific interface to invoke
  2572 Proof General / Emacs, with more explicit failure if that is not
  2573 installed (the old isabelle-interface script silently falls back on
  2574 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2575 installation location of the Proof General distribution.
  2576 
  2577 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2578 the Isabelle process into a JVM/Scala application.  See
  2579 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2580 process wrapper has been discontinued.)
  2581 
  2582 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2583 
  2584 * Various status messages (with exact source position information) are
  2585 emitted, if proper markup print mode is enabled.  This allows
  2586 user-interface components to provide detailed feedback on internal
  2587 prover operations.
  2588 
  2589 
  2590 
  2591 New in Isabelle2008 (June 2008)
  2592 -------------------------------
  2593 
  2594 *** General ***
  2595 
  2596 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2597 and updated, with formally checked references as hyperlinks.
  2598 
  2599 * Theory loader: use_thy (and similar operations) no longer set the
  2600 implicit ML context, which was occasionally hard to predict and in
  2601 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2602 provides a proper context already.
  2603 
  2604 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2605 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2606 'use' within a theory file will do the job.
  2607 
  2608 * Name space merge now observes canonical order, i.e. the second space
  2609 is inserted into the first one, while existing entries in the first
  2610 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2611 swap theory imports.
  2612 
  2613 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2614 INCOMPATIBILITY in identifier syntax etc.
  2615 
  2616 * Outer syntax: string tokens no longer admit escaped white space,
  2617 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2618 white space without escapes.
  2619 
  2620 * Outer syntax: string tokens may contain arbitrary character codes
  2621 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2622 "foo_bar".
  2623 
  2624 
  2625 *** Pure ***
  2626 
  2627 * Context-dependent token translations.  Default setup reverts locally
  2628 fixed variables, and adds hilite markup for undeclared frees.
  2629 
  2630 * Unused theorems can be found using the new command 'unused_thms'.
  2631 There are three ways of invoking it:
  2632 
  2633 (1) unused_thms
  2634      Only finds unused theorems in the current theory.
  2635 
  2636 (2) unused_thms thy_1 ... thy_n -
  2637      Finds unused theorems in the current theory and all of its ancestors,
  2638      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2639 
  2640 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2641      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2642      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2643      their ancestors.
  2644 
  2645 In order to increase the readability of the list produced by
  2646 unused_thms, theorems that have been created by a particular instance
  2647 of a theory command such as 'inductive' or 'function' are considered
  2648 to belong to the same "group", meaning that if at least one theorem in
  2649 this group is used, the other theorems in the same group are no longer
  2650 reported as unused.  Moreover, if all theorems in the group are
  2651 unused, only one theorem in the group is displayed.
  2652 
  2653 Note that proof objects have to be switched on in order for
  2654 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2655 usually the case when using Proof General with the default settings).
  2656 
  2657 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2658 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2659 duplicate fact bindings, or even accidental fact duplications.  Note
  2660 that tools may maintain dynamically scoped facts systematically, using
  2661 PureThy.add_thms_dynamic.
  2662 
  2663 * Command 'hide' now allows to hide from "fact" name space as well.
  2664 
  2665 * Eliminated destructive theorem database, simpset, claset, and
  2666 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2667 update of theories within ML code.
  2668 
  2669 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2670 INCOMPATIBILITY, object-logics depending on former Pure require
  2671 additional setup PureThy.old_appl_syntax_setup; object-logics
  2672 depending on former CPure need to refer to Pure.
  2673 
  2674 * Commands 'use' and 'ML' are now purely functional, operating on
  2675 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2676 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2677 INCOMPATIBILITY.
  2678 
  2679 * Command 'setup': discontinued implicit version with ML reference.
  2680 
  2681 * Instantiation target allows for simultaneous specification of class
  2682 instance operations together with an instantiation proof.
  2683 Type-checking phase allows to refer to class operations uniformly.
  2684 See src/HOL/Complex/Complex.thy for an Isar example and
  2685 src/HOL/Library/Eval.thy for an ML example.
  2686 
  2687 * Indexing of literal facts: be more serious about including only
  2688 facts from the visible specification/proof context, but not the
  2689 background context (locale etc.).  Affects `prop` notation and method
  2690 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2691 situations.
  2692 
  2693 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2694 "(open)" option, which used to expose internal bound variables to the
  2695 proof text.
  2696 
  2697 * Isar statements: removed obsolete case "rule_context".
  2698 INCOMPATIBILITY, better use explicit fixes/assumes.
  2699 
  2700 * Locale proofs: default proof step now includes 'unfold_locales';
  2701 hence 'proof' without argument may be used to unfold locale
  2702 predicates.
  2703 
  2704 
  2705 *** Document preparation ***
  2706 
  2707 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2708 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2709 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2710 spot); renamed link color from "darkblue" to "linkcolor" (default
  2711 value unchanged, can be redefined via \definecolor); no longer sets
  2712 "a4paper" option (unnecessary or even intrusive).
  2713 
  2714 * Antiquotation @{lemma A method} proves proposition A by the given
  2715 method (either a method name or a method name plus (optional) method
  2716 arguments in parentheses) and prints A just like @{prop A}.
  2717 
  2718 
  2719 *** HOL ***
  2720 
  2721 * New primrec package.  Specification syntax conforms in style to
  2722 definition/function/....  No separate induction rule is provided.  The
  2723 "primrec" command distinguishes old-style and new-style specifications
  2724 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2725 When adjusting theories, beware: constants stemming from new-style
  2726 primrec specifications have authentic syntax.
  2727 
  2728 * Metis prover is now an order of magnitude faster, and also works
  2729 with multithreading.
  2730 
  2731 * Metis: the maximum number of clauses that can be produced from a
  2732 theorem is now given by the attribute max_clauses.  Theorems that
  2733 exceed this number are ignored, with a warning printed.
  2734 
  2735 * Sledgehammer no longer produces structured proofs by default. To
  2736 enable, declare [[sledgehammer_full = true]].  Attributes
  2737 reconstruction_modulus, reconstruction_sorts renamed
  2738 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2739 
  2740 * Method "induct_scheme" derives user-specified induction rules
  2741 from well-founded induction and completeness of patterns. This factors
  2742 out some operations that are done internally by the function package
  2743 and makes them available separately.  See
  2744 src/HOL/ex/Induction_Scheme.thy for examples.
  2745 
  2746 * More flexible generation of measure functions for termination
  2747 proofs: Measure functions can be declared by proving a rule of the
  2748 form "is_measure f" and giving it the [measure_function] attribute.
  2749 The "is_measure" predicate is logically meaningless (always true), and
  2750 just guides the heuristic.  To find suitable measure functions, the
  2751 termination prover sets up the goal "is_measure ?f" of the appropriate
  2752 type and generates all solutions by prolog-style backwards proof using
  2753 the declared rules.
  2754 
  2755 This setup also deals with rules like 
  2756 
  2757   "is_measure f ==> is_measure (list_size f)"
  2758 
  2759 which accommodates nested datatypes that recurse through lists.
  2760 Similar rules are predeclared for products and option types.
  2761 
  2762 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2763 
  2764   INCOMPATIBILITIES:
  2765 
  2766   - Definitions of overloaded constants on sets have to be replaced by
  2767     definitions on => and bool.
  2768 
  2769   - Some definitions of overloaded operators on sets can now be proved
  2770     using the definitions of the operators on => and bool.  Therefore,
  2771     the following theorems have been renamed:
  2772 
  2773       subset_def   -> subset_eq
  2774       psubset_def  -> psubset_eq
  2775       set_diff_def -> set_diff_eq
  2776       Compl_def    -> Compl_eq
  2777       Sup_set_def  -> Sup_set_eq
  2778       Inf_set_def  -> Inf_set_eq
  2779       sup_set_def  -> sup_set_eq
  2780       inf_set_def  -> inf_set_eq
  2781 
  2782   - Due to the incompleteness of the HO unification algorithm, some
  2783     rules such as subst may require manual instantiation, if some of
  2784     the unknowns in the rule is a set.
  2785 
  2786   - Higher order unification and forward proofs:
  2787     The proof pattern
  2788 
  2789       have "P (S::'a set)" <...>
  2790       then have "EX S. P S" ..
  2791 
  2792     no longer works (due to the incompleteness of the HO unification
  2793     algorithm) and must be replaced by the pattern
  2794 
  2795       have "EX S. P S"
  2796       proof
  2797         show "P S" <...>
  2798       qed
  2799 
  2800   - Calculational reasoning with subst (or similar rules):
  2801     The proof pattern
  2802 
  2803       have "P (S::'a set)" <...>
  2804       also have "S = T" <...>
  2805       finally have "P T" .
  2806 
  2807     no longer works (for similar reasons as the previous example) and
  2808     must be replaced by something like
  2809 
  2810       have "P (S::'a set)" <...>
  2811       moreover have "S = T" <...>
  2812       ultimately have "P T" by simp
  2813 
  2814   - Tactics or packages written in ML code:
  2815     Code performing pattern matching on types via
  2816 
  2817       Type ("set", [T]) => ...
  2818 
  2819     must be rewritten. Moreover, functions like strip_type or
  2820     binder_types no longer return the right value when applied to a
  2821     type of the form
  2822 
  2823       T1 => ... => Tn => U => bool
  2824 
  2825     rather than
  2826 
  2827       T1 => ... => Tn => U set
  2828 
  2829 * Merged theories Wellfounded_Recursion, Accessible_Part and
  2830 Wellfounded_Relations to theory Wellfounded.
  2831 
  2832 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  2833 
  2834 * Class finite no longer treats UNIV as class parameter.  Use class
  2835 enum from theory Library/Enum instead to achieve a similar effect.
  2836 INCOMPATIBILITY.
  2837 
  2838 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  2839 and "Cons".  INCOMPATIBILITY.
  2840 
  2841 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  2842 Potential INCOMPATIBILITY.
  2843 
  2844 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  2845 injective_fst_snd removed, use split_eta and prod_eqI instead.
  2846 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  2847 
  2848 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  2849 the same name in theory Orderings:
  2850 
  2851   less_trans
  2852   less_linear
  2853   le_imp_less_or_eq
  2854   le_less_trans
  2855   less_le_trans
  2856   less_not_sym
  2857   less_asym
  2858 
  2859 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  2860 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  2861 and different variable names.
  2862 
  2863 * Library/Option_ord.thy: Canonical order on option type.
  2864 
  2865 * Library/RBT.thy: Red-black trees, an efficient implementation of
  2866 finite maps.
  2867 
  2868 * Library/Countable.thy: Type class for countable types.
  2869 
  2870 * Theory Int: The representation of numerals has changed.  The infix
  2871 operator BIT and the bit datatype with constructors B0 and B1 have
  2872 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  2873 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  2874 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  2875 accordingly.
  2876 
  2877 * Theory Nat: definition of <= and < on natural numbers no longer
  2878 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  2879 le_def and less_def have disappeared.  Consider lemmas not_less
  2880 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  2881 
  2882 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  2883 (whose purpose mainly is for various fold_set functionals) have been
  2884 abandoned in favor of the existing algebraic classes
  2885 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  2886 lower_semilattice (resp. upper_semilattice) and linorder.
  2887 INCOMPATIBILITY.
  2888 
  2889 * Theory Transitive_Closure: induct and cases rules now declare proper
  2890 case_names ("base" and "step").  INCOMPATIBILITY.
  2891 
  2892 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  2893 lattices.  The form set-specific version is available as
  2894 Inductive.lfp_ordinal_induct_set.
  2895 
  2896 * Renamed theorems "power.simps" to "power_int.simps".
  2897 INCOMPATIBILITY.
  2898 
  2899 * Class semiring_div provides basic abstract properties of semirings
  2900 with division and modulo operations.  Subsumes former class dvd_mod.
  2901 
  2902 * Merged theories IntDef, Numeral and IntArith into unified theory
  2903 Int.  INCOMPATIBILITY.
  2904 
  2905 * Theory Library/Code_Index: type "index" now represents natural
  2906 numbers rather than integers.  INCOMPATIBILITY.
  2907 
  2908 * New class "uminus" with operation "uminus" (split of from class
  2909 "minus" which now only has operation "minus", binary).
  2910 INCOMPATIBILITY.
  2911 
  2912 * Constants "card", "internal_split", "option_map" now with authentic
  2913 syntax.  INCOMPATIBILITY.
  2914 
  2915 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  2916 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  2917 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  2918 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  2919 Sup_set_def, le_def, less_def, option_map_def now with object
  2920 equality.  INCOMPATIBILITY.
  2921 
  2922 * Records. Removed K_record, and replaced it by pure lambda term
  2923 %x. c. The simplifier setup is now more robust against eta expansion.
  2924 INCOMPATIBILITY: in cases explicitly referring to K_record.
  2925 
  2926 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  2927 
  2928 * Library/ListVector: new theory of arithmetic vector operations.
  2929 
  2930 * Library/Order_Relation: new theory of various orderings as sets of
  2931 pairs.  Defines preorders, partial orders, linear orders and
  2932 well-orders on sets and on types.
  2933 
  2934 
  2935 *** ZF ***
  2936 
  2937 * Renamed some theories to allow to loading both ZF and HOL in the
  2938 same session:
  2939 
  2940   Datatype  -> Datatype_ZF
  2941   Inductive -> Inductive_ZF
  2942   Int       -> Int_ZF
  2943   IntDiv    -> IntDiv_ZF
  2944   Nat       -> Nat_ZF
  2945   List      -> List_ZF
  2946   Main      -> Main_ZF
  2947 
  2948 INCOMPATIBILITY: ZF theories that import individual theories below
  2949 Main might need to be adapted.  Regular theory Main is still
  2950 available, as trivial extension of Main_ZF.
  2951 
  2952 
  2953 *** ML ***
  2954 
  2955 * ML within Isar: antiquotation @{const name} or @{const
  2956 name(typargs)} produces statically-checked Const term.
  2957 
  2958 * Functor NamedThmsFun: data is available to the user as dynamic fact
  2959 (of the same name).  Removed obsolete print command.
  2960 
  2961 * Removed obsolete "use_legacy_bindings" function.
  2962 
  2963 * The ``print mode'' is now a thread-local value derived from a global
  2964 template (the former print_mode reference), thus access becomes
  2965 non-critical.  The global print_mode reference is for session
  2966 management only; user-code should use print_mode_value,
  2967 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  2968 
  2969 * Functions system/system_out provide a robust way to invoke external
  2970 shell commands, with propagation of interrupts (requires Poly/ML
  2971 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  2972 
  2973 
  2974 *** System ***
  2975 
  2976 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  2977 in accordance with Proof General 3.7, which prefers GNU emacs.
  2978 
  2979 * isatool tty runs Isabelle process with plain tty interaction;
  2980 optional line editor may be specified via ISABELLE_LINE_EDITOR
  2981 setting, the default settings attempt to locate "ledit" and "rlwrap".
  2982 
  2983 * isatool browser now works with Cygwin as well, using general
  2984 "javapath" function defined in Isabelle process environment.
  2985 
  2986 * YXML notation provides a simple and efficient alternative to
  2987 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  2988 isatool yxml as described in the Isabelle system manual.
  2989 
  2990 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  2991 provides general wrapper for managing an Isabelle process in a robust
  2992 fashion, with ``cooked'' output from stdin/stderr.
  2993 
  2994 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  2995 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  2996 
  2997 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  2998 way of changing the user's settings is via
  2999 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3000 script.
  3001 
  3002 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3003 cores of the underlying machine, which is a good starting point for
  3004 optimal performance tuning.  The corresponding usedir option -M allows
  3005 "max" as an alias for "0".  WARNING: does not work on certain versions
  3006 of Mac OS (with Poly/ML 5.1).
  3007 
  3008 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3009 adverse effect of Isabelle flooding interactive front-ends (notably
  3010 ProofGeneral / XEmacs).
  3011 
  3012 
  3013 
  3014 New in Isabelle2007 (November 2007)
  3015 -----------------------------------
  3016 
  3017 *** General ***
  3018 
  3019 * More uniform information about legacy features, notably a
  3020 warning/error of "Legacy feature: ...", depending on the state of the
  3021 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3022 legacy features will disappear eventually.
  3023 
  3024 * Theory syntax: the header format ``theory A = B + C:'' has been
  3025 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3026 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3027 
  3028 * Theory syntax: the old non-Isar theory file format has been
  3029 discontinued altogether.  Note that ML proof scripts may still be used
  3030 with Isar theories; migration is usually quite simple with the ML
  3031 function use_legacy_bindings.  INCOMPATIBILITY.
  3032 
  3033 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3034 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3035 quotes.
  3036 
  3037 * Theory loader: be more serious about observing the static theory
  3038 header specifications (including optional directories), but not the
  3039 accidental file locations of previously successful loads.  The strict
  3040 update policy of former update_thy is now already performed by
  3041 use_thy, so the former has been removed; use_thys updates several
  3042 theories simultaneously, just as 'imports' within a theory header
  3043 specification, but without merging the results.  Potential
  3044 INCOMPATIBILITY: may need to refine theory headers and commands
  3045 ROOT.ML which depend on load order.
  3046 
  3047 * Theory loader: optional support for content-based file
  3048 identification, instead of the traditional scheme of full physical
  3049 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3050 (cf. the system manual).  The new scheme allows to work with
  3051 non-finished theories in persistent session images, such that source
  3052 files may be moved later on without requiring reloads.
  3053 
  3054 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3055 file (with the same base name as the theory) are considered a legacy
  3056 feature, which will disappear eventually. Even now, the theory loader
  3057 no longer maintains dependencies on such files.
  3058 
  3059 * Syntax: the scope for resolving ambiguities via type-inference is
  3060 now limited to individual terms, instead of whole simultaneous
  3061 specifications as before. This greatly reduces the complexity of the
  3062 syntax module and improves flexibility by separating parsing and
  3063 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3064 'fixes' etc.) are required in rare situations.
  3065 
  3066 * Syntax: constants introduced by new-style packages ('definition',
  3067 'abbreviation' etc.) are passed through the syntax module in
  3068 ``authentic mode''. This means that associated mixfix annotations
  3069 really stick to such constants, independently of potential name space
  3070 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3071 trees are represented slightly differently, may need to adapt syntax
  3072 translations accordingly. Use CONST marker in 'translations' and
  3073 @{const_syntax} antiquotation in 'parse_translation' etc.
  3074 
  3075 * Legacy goal package: reduced interface to the bare minimum required
  3076 to keep existing proof scripts running.  Most other user-level
  3077 functions are now part of the OldGoals structure, which is *not* open
  3078 by default (consider isatool expandshort before open OldGoals).
  3079 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3080 these tend to cause confusion about the actual goal (!) context being
  3081 used here, which is not necessarily the same as the_context().
  3082 
  3083 * Command 'find_theorems': supports "*" wild-card in "name:"
  3084 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3085 support a specific search form (see ProofGeneral/CHANGES).
  3086 
  3087 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3088 by default, which means that "prems" (and also "fixed variables") are
  3089 suppressed from proof state output.  Note that the ProofGeneral
  3090 settings mechanism allows to change and save options persistently, but
  3091 older versions of Isabelle will fail to start up if a negative prems
  3092 limit is imposed.
  3093 
  3094 * Local theory targets may be specified by non-nested blocks of
  3095 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3096 contain definitions, theorems etc., including any derived mechanism
  3097 that has been implemented on top of these primitives.  This concept
  3098 generalizes the existing ``theorem (in ...)'' towards more versatility
  3099 and scalability.
  3100 
  3101 * Proof General interface: proper undo of final 'end' command;
  3102 discontinued Isabelle/classic mode (ML proof scripts).
  3103 
  3104 
  3105 *** Document preparation ***
  3106 
  3107 * Added antiquotation @{theory name} which prints the given name,
  3108 after checking that it refers to a valid ancestor theory in the
  3109 current context.
  3110 
  3111 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3112 check the given source text as ML type/structure, printing verbatim.
  3113 
  3114 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3115 "c args == rhs" given in the current context.  (Any number of
  3116 arguments may be given on the LHS.)
  3117 
  3118 
  3119 *** Pure ***
  3120 
  3121 * The 'class' package offers a combination of axclass and locale to
  3122 achieve Haskell-like type classes in Isabelle.  Definitions and
  3123 theorems within a class context produce both relative results (with
  3124 implicit parameters according to the locale context), and polymorphic
  3125 constants with qualified polymorphism (according to the class
  3126 context).  Within the body context of a 'class' target, a separate
  3127 syntax layer ("user space type system") takes care of converting
  3128 between global polymorphic consts and internal locale representation.
  3129 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3130 "isatool doc classes" provides a tutorial.
  3131 
  3132 * Generic code generator framework allows to generate executable
  3133 code for ML and Haskell (including Isabelle classes).  A short usage
  3134 sketch:
  3135 
  3136     internal compilation:
  3137         export_code <list of constants (term syntax)> in SML
  3138     writing SML code to a file:
  3139         export_code <list of constants (term syntax)> in SML <filename>
  3140     writing OCaml code to a file:
  3141         export_code <list of constants (term syntax)> in OCaml <filename>
  3142     writing Haskell code to a bunch of files:
  3143         export_code <list of constants (term syntax)> in Haskell <filename>
  3144 
  3145     evaluating closed propositions to True/False using code generation:
  3146         method ``eval''
  3147 
  3148 Reasonable default setup of framework in HOL.
  3149 
  3150 Theorem attributs for selecting and transforming function equations theorems:
  3151 
  3152     [code fun]:        select a theorem as function equation for a specific constant
  3153     [code fun del]:    deselect a theorem as function equation for a specific constant
  3154     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3155     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3156 
  3157 User-defined serializations (target in {SML, OCaml, Haskell}):
  3158 
  3159     code_const <and-list of constants (term syntax)>
  3160       {(target) <and-list of const target syntax>}+
  3161 
  3162     code_type <and-list of type constructors>
  3163       {(target) <and-list of type target syntax>}+
  3164 
  3165     code_instance <and-list of instances>
  3166       {(target)}+
  3167         where instance ::= <type constructor> :: <class>
  3168 
  3169     code_class <and_list of classes>
  3170       {(target) <and-list of class target syntax>}+
  3171         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3172 
  3173 code_instance and code_class only are effective to target Haskell.
  3174 
  3175 For example usage see src/HOL/ex/Codegenerator.thy and
  3176 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3177 generation from Isabelle/HOL theories is available via "isatool doc
  3178 codegen".
  3179 
  3180 * Code generator: consts in 'consts_code' Isar commands are now
  3181 referred to by usual term syntax (including optional type
  3182 annotations).
  3183 
  3184 * Command 'no_translations' removes translation rules from theory
  3185 syntax.
  3186 
  3187 * Overloaded definitions are now actually checked for acyclic
  3188 dependencies.  The overloading scheme is slightly more general than
  3189 that of Haskell98, although Isabelle does not demand an exact
  3190 correspondence to type class and instance declarations.
  3191 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3192 exotic versions of overloading -- at the discretion of the user!
  3193 
  3194 Polymorphic constants are represented via type arguments, i.e. the
  3195 instantiation that matches an instance against the most general
  3196 declaration given in the signature.  For example, with the declaration
  3197 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3198 as c(nat).  Overloading is essentially simultaneous structural
  3199 recursion over such type arguments.  Incomplete specification patterns
  3200 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3201 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3202 Command 'print_theory' outputs the normalized system of recursive
  3203 equations, see section "definitions".
  3204 
  3205 * Configuration options are maintained within the theory or proof
  3206 context (with name and type bool/int/string), providing a very simple
  3207 interface to a poor-man's version of general context data.  Tools may
  3208 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3209 these values using Config.get etc.  Users may change options via an
  3210 associated attribute of the same name.  This form of context
  3211 declaration works particularly well with commands 'declare' or
  3212 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3213 very easy to avoid global references, which would not observe Isar
  3214 toplevel undo/redo and fail to work with multithreading.
  3215 
  3216 Various global ML references of Pure and HOL have been turned into
  3217 configuration options:
  3218 
  3219   Unify.search_bound		unify_search_bound
  3220   Unify.trace_bound		unify_trace_bound
  3221   Unify.trace_simp		unify_trace_simp
  3222   Unify.trace_types		unify_trace_types
  3223   Simplifier.simp_depth_limit	simp_depth_limit
  3224   Blast.depth_limit		blast_depth_limit
  3225   DatatypeProp.dtK		datatype_distinctness_limit
  3226   fast_arith_neq_limit  	fast_arith_neq_limit
  3227   fast_arith_split_limit	fast_arith_split_limit
  3228 
  3229 * Named collections of theorems may be easily installed as context
  3230 data using the functor NamedThmsFun (see also
  3231 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3232 attributes; there is also a toplevel print command.  This facility is
  3233 just a common case of general context data, which is the preferred way
  3234 for anything more complex than just a list of facts in canonical
  3235 order.
  3236 
  3237 * Isar: command 'declaration' augments a local theory by generic
  3238 declaration functions written in ML.  This enables arbitrary content
  3239 being added to the context, depending on a morphism that tells the
  3240 difference of the original declaration context wrt. the application
  3241 context encountered later on.
  3242 
  3243 * Isar: proper interfaces for simplification procedures.  Command
  3244 'simproc_setup' declares named simprocs (with match patterns, and body
  3245 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3246 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3247 
  3248 * Isar: an extra pair of brackets around attribute declarations
  3249 abbreviates a theorem reference involving an internal dummy fact,
  3250 which will be ignored later --- only the effect of the attribute on
  3251 the background context will persist.  This form of in-place
  3252 declarations is particularly useful with commands like 'declare' and
  3253 'using', for example ``have A using [[simproc a]] by simp''.
  3254 
  3255 * Isar: method "assumption" (and implicit closing of subproofs) now
  3256 takes simple non-atomic goal assumptions into account: after applying
  3257 an assumption as a rule the resulting subgoals are solved by atomic
  3258 assumption steps.  This is particularly useful to finish 'obtain'
  3259 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3260 without referring to the original premise "!!x. P x ==> thesis" in the
  3261 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3262 more permissive.
  3263 
  3264 * Isar: implicit use of prems from the Isar proof context is
  3265 considered a legacy feature.  Common applications like ``have A .''
  3266 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3267 referencing facts explicitly here improves readability and
  3268 maintainability of proof texts.
  3269 
  3270 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3271 the obtained context from the course of reasoning!  For example:
  3272 
  3273   assume "EX x y. A x & B y"   -- "any previous fact"
  3274   then guess x and y by clarify
  3275 
  3276 This technique is potentially adventurous, depending on the facts and
  3277 proof tools being involved here.
  3278 
  3279 * Isar: known facts from the proof context may be specified as literal
  3280 propositions, using ASCII back-quote syntax.  This works wherever
  3281 named facts used to be allowed so far, in proof commands, proof
  3282 methods, attributes etc.  Literal facts are retrieved from the context
  3283 according to unification of type and term parameters.  For example,
  3284 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3285 theorems in the current context, then these are valid literal facts:
  3286 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3287 
  3288 There is also a proof method "fact" which does the same composition
  3289 for explicit goal states, e.g. the following proof texts coincide with
  3290 certain special cases of literal facts:
  3291 
  3292   have "A" by fact                 ==  note `A`
  3293   have "A ==> B" by fact           ==  note `A ==> B`
  3294   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3295   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3296 
  3297 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3298 outer syntax.  Thus symbolic identifiers may be used without
  3299 additional white space in declarations like this: ``assume *: A''.
  3300 
  3301 * Isar: 'print_facts' prints all local facts of the current context,
  3302 both named and unnamed ones.
  3303 
  3304 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3305 
  3306   def x == "t" and y == "u"
  3307 
  3308 * Isar: added command 'unfolding', which is structurally similar to
  3309 'using', but affects both the goal state and facts by unfolding given
  3310 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3311 'unfolded' attribute may be replaced by first-class proof text.
  3312 
  3313 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3314 and command 'unfolding' now all support object-level equalities
  3315 (potentially conditional).  The underlying notion of rewrite rule is
  3316 analogous to the 'rule_format' attribute, but *not* that of the
  3317 Simplifier (which is usually more generous).
  3318 
  3319 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3320 premises of a theorem by n. Useful in conjunction with drule.
  3321 
  3322 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3323 method expression within a sandbox consisting of the first N
  3324 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3325 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3326 simplifies all new goals that emerge from applying rule foo to the
  3327 originally first one.
  3328 
  3329 * Isar: schematic goals are no longer restricted to higher-order
  3330 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3331 expected.
  3332 
  3333 * Isar: the conclusion of a long theorem statement is now either
  3334 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3335 (essentially a disjunction of cases with local parameters and
  3336 assumptions).  The latter allows to express general elimination rules
  3337 adequately; in this notation common elimination rules look like this:
  3338 
  3339   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3340     assumes "EX x. P x"
  3341     obtains x where "P x"
  3342 
  3343   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3344     assumes "A & B"
  3345     obtains A and B
  3346 
  3347   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3348     assumes "A | B"
  3349     obtains
  3350       A
  3351     | B
  3352 
  3353 The subsequent classical rules even refer to the formal "thesis"
  3354 explicitly:
  3355 
  3356   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3357     obtains "~ thesis"
  3358 
  3359   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3360     obtains "thesis ==> something"
  3361 
  3362 The actual proof of an 'obtains' statement is analogous to that of the
  3363 Isar proof element 'obtain', only that there may be several cases.
  3364 Optional case names may be specified in parentheses; these will be
  3365 available both in the present proof and as annotations in the
  3366 resulting rule, for later use with the 'cases' method (cf. attribute
  3367 case_names).
  3368 
  3369 * Isar: the assumptions of a long theorem statement are available as
  3370 "assms" fact in the proof context.  This is more appropriate than the
  3371 (historical) "prems", which refers to all assumptions of the current
  3372 context, including those from the target locale, proof body etc.
  3373 
  3374 * Isar: 'print_statement' prints theorems from the current theory or
  3375 proof context in long statement form, according to the syntax of a
  3376 top-level lemma.
  3377 
  3378 * Isar: 'obtain' takes an optional case name for the local context
  3379 introduction rule (default "that").
  3380 
  3381 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3382 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3383 to occur.
  3384 
  3385 * Pure: syntax "CONST name" produces a fully internalized constant
  3386 according to the current context.  This is particularly useful for
  3387 syntax translations that should refer to internal constant
  3388 representations independently of name spaces.
  3389 
  3390 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3391 instead of "FOO ". This allows multiple binder declarations to coexist
  3392 in the same context.  INCOMPATIBILITY.
  3393 
  3394 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3395 primitive that also works in a locale context (both for constants and
  3396 fixed variables). Type declaration and internal syntactic representation
  3397 of given constants retrieved from the context. Likewise, the
  3398 'no_notation' command allows to remove given syntax annotations from the
  3399 current context.
  3400 
  3401 * Isar/locales: new derived specification elements 'axiomatization',
  3402 'definition', 'abbreviation', which support type-inference, admit
  3403 object-level specifications (equality, equivalence).  See also the
  3404 isar-ref manual.  Examples:
  3405 
  3406   axiomatization
  3407     eq  (infix "===" 50) where
  3408     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3409 
  3410   definition "f x y = x + y + 1"
  3411   definition g where "g x = f x x"
  3412 
  3413   abbreviation
  3414     neq  (infix "=!=" 50) where
  3415     "x =!= y == ~ (x === y)"
  3416 
  3417 These specifications may be also used in a locale context.  Then the
  3418 constants being introduced depend on certain fixed parameters, and the
  3419 constant name is qualified by the locale base name.  An internal
  3420 abbreviation takes care for convenient input and output, making the
  3421 parameters implicit and using the original short name.  See also
  3422 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3423 entities from a monomorphic theory.
  3424 
  3425 Presently, abbreviations are only available 'in' a target locale, but
  3426 not inherited by general import expressions.  Also note that
  3427 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3428 'translations' in common applications.  The "no_abbrevs" print mode
  3429 prevents folding of abbreviations in term output.
  3430 
  3431 Concrete syntax is attached to specified constants in internal form,
  3432 independently of name spaces.  The parse tree representation is
  3433 slightly different -- use 'notation' instead of raw 'syntax', and
  3434 'translations' with explicit "CONST" markup to accommodate this.
  3435 
  3436 * Pure/Isar: unified syntax for new-style specification mechanisms
  3437 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3438 full type inference and dummy patterns ("_").  For example:
  3439 
  3440   definition "K x _ = x"
  3441 
  3442   inductive conj for A B
  3443   where "A ==> B ==> conj A B"
  3444 
  3445 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3446 the current context.  Print mode "no_abbrevs" prevents inversion of
  3447 abbreviations on output.
  3448 
  3449 * Isar/locales: improved parameter handling: use of locales "var" and
  3450 "struct" no longer necessary; - parameter renamings are no longer
  3451 required to be injective.  For example, this allows to define
  3452 endomorphisms as locale endom = homom mult mult h.
  3453 
  3454 * Isar/locales: changed the way locales with predicates are defined.
  3455 Instead of accumulating the specification, the imported expression is
  3456 now an interpretation.  INCOMPATIBILITY: different normal form of
  3457 locale expressions.  In particular, in interpretations of locales with
  3458 predicates, goals repesenting already interpreted fragments are not
  3459 removed automatically.  Use methods `intro_locales' and
  3460 `unfold_locales'; see below.
  3461 
  3462 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3463 provide backward reasoning on locales predicates.  The methods are
  3464 aware of interpretations and discharge corresponding goals.
  3465 `intro_locales' is less aggressive then `unfold_locales' and does not
  3466 unfold predicates to assumptions.
  3467 
  3468 * Isar/locales: the order in which locale fragments are accumulated
  3469 has changed.  This enables to override declarations from fragments due
  3470 to interpretations -- for example, unwanted simp rules.
  3471 
  3472 * Isar/locales: interpretation in theories and proof contexts has been
  3473 extended.  One may now specify (and prove) equations, which are
  3474 unfolded in interpreted theorems.  This is useful for replacing
  3475 defined concepts (constants depending on locale parameters) by
  3476 concepts already existing in the target context.  Example:
  3477 
  3478   interpretation partial_order ["op <= :: [int, int] => bool"]
  3479     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3480 
  3481 Typically, the constant `partial_order.less' is created by a
  3482 definition specification element in the context of locale
  3483 partial_order.
  3484 
  3485 * Method "induct": improved internal context management to support
  3486 local fixes and defines on-the-fly. Thus explicit meta-level
  3487 connectives !!  and ==> are rarely required anymore in inductive goals
  3488 (using object-logic connectives for this purpose has been long
  3489 obsolete anyway). Common proof patterns are explained in
  3490 src/HOL/Induct/Common_Patterns.thy, see also
  3491 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3492 examples.
  3493 
  3494 * Method "induct": improved handling of simultaneous goals. Instead of
  3495 introducing object-level conjunction, the statement is now split into
  3496 several conclusions, while the corresponding symbolic cases are nested
  3497 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3498 see src/HOL/Induct/Common_Patterns.thy, for example.
  3499 
  3500 * Method "induct": mutual induction rules are now specified as a list
  3501 of rule sharing the same induction cases. HOL packages usually provide
  3502 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3503 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3504 mutual induction rules differently, i.e. like this:
  3505 
  3506   (induct rule: foo_bar.inducts)
  3507   (induct set: foo bar)
  3508   (induct pred: foo bar)
  3509   (induct type: foo bar)
  3510 
  3511 The ML function ProjectRule.projections turns old-style rules into the
  3512 new format.
  3513 
  3514 * Method "coinduct": dual of induction, see
  3515 src/HOL/Library/Coinductive_List.thy for various examples.
  3516 
  3517 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3518 considered a legacy feature.
  3519 
  3520 * Attribute "symmetric" produces result with standardized schematic
  3521 variables (index 0).  Potential INCOMPATIBILITY.
  3522 
  3523 * Simplifier: by default the simplifier trace only shows top level
  3524 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3525 default. Thus there is less danger of being flooded by the trace. The
  3526 trace indicates where parts have been suppressed.
  3527   
  3528 * Provers/classical: removed obsolete classical version of elim_format
  3529 attribute; classical elim/dest rules are now treated uniformly when
  3530 manipulating the claset.
  3531 
  3532 * Provers/classical: stricter checks to ensure that supplied intro,
  3533 dest and elim rules are well-formed; dest and elim rules must have at
  3534 least one premise.
  3535 
  3536 * Provers/classical: attributes dest/elim/intro take an optional
  3537 weight argument for the rule (just as the Pure versions).  Weights are
  3538 ignored by automated tools, but determine the search order of single
  3539 rule steps.
  3540 
  3541 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3542 where the body does not mention the bound variable.  Note that dummy
  3543 patterns implicitly depend on their context of bounds, which makes
  3544 "{_. _}" match any set comprehension as expected.  Potential
  3545 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3546 constant "_idtdummy" in the binding position.
  3547 
  3548 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3549 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3550 for example "A -> B" => "Pi A (%_. B)".
  3551 
  3552 * Pure: 'class_deps' command visualizes the subclass relation, using
  3553 the graph browser tool.
  3554 
  3555 * Pure: 'print_theory' now suppresses certain internal declarations by
  3556 default; use '!' option for full details.
  3557 
  3558 
  3559 *** HOL ***
  3560 
  3561 * Method "metis" proves goals by applying the Metis general-purpose
  3562 resolution prover (see also http://gilith.com/software/metis/).
  3563 Examples are in the directory MetisExamples.  WARNING: the
  3564 Isabelle/HOL-Metis integration does not yet work properly with
  3565 multi-threading.
  3566   
  3567 * Command 'sledgehammer' invokes external automatic theorem provers as
  3568 background processes.  It generates calls to the "metis" method if
  3569 successful. These can be pasted into the proof.  Users do not have to
  3570 wait for the automatic provers to return.  WARNING: does not really
  3571 work with multi-threading.
  3572 
  3573 * New "auto_quickcheck" feature tests outermost goal statements for
  3574 potential counter-examples.  Controlled by ML references
  3575 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3576 5000 milliseconds).  Fails silently if statements is outside of
  3577 executable fragment, or any other codgenerator problem occurs.
  3578 
  3579 * New constant "undefined" with axiom "undefined x = undefined".
  3580 
  3581 * Added class "HOL.eq", allowing for code generation with polymorphic
  3582 equality.
  3583 
  3584 * Some renaming of class constants due to canonical name prefixing in
  3585 the new 'class' package:
  3586 
  3587     HOL.abs ~> HOL.abs_class.abs
  3588     HOL.divide ~> HOL.divide_class.divide
  3589     0 ~> HOL.zero_class.zero
  3590     1 ~> HOL.one_class.one
  3591     op + ~> HOL.plus_class.plus
  3592     op - ~> HOL.minus_class.minus
  3593     uminus ~> HOL.minus_class.uminus
  3594     op * ~> HOL.times_class.times
  3595     op < ~> HOL.ord_class.less
  3596     op <= > HOL.ord_class.less_eq
  3597     Nat.power ~> Power.power_class.power
  3598     Nat.size ~> Nat.size_class.size
  3599     Numeral.number_of ~> Numeral.number_class.number_of
  3600     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3601     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3602     Orderings.min ~> Orderings.ord_class.min
  3603     Orderings.max ~> Orderings.ord_class.max
  3604     Divides.op div ~> Divides.div_class.div
  3605     Divides.op mod ~> Divides.div_class.mod
  3606     Divides.op dvd ~> Divides.div_class.dvd
  3607 
  3608 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3609 
  3610 a) User-defined constants using any of the names "plus", "minus",
  3611 "times", "less" or "less_eq". The standard syntax translations for
  3612 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3613 names.
  3614 
  3615 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3616 INCOMPATIBILITY: use more specific names.
  3617 
  3618 c) Permutative equations (e.g. "a + b = b + a")
  3619 Since the change of names also changes the order of terms, permutative
  3620 rewrite rules may get applied in a different order. Experience shows
  3621 that this is rarely the case (only two adaptions in the whole Isabelle
  3622 distribution).  INCOMPATIBILITY: rewrite proofs
  3623 
  3624 d) ML code directly refering to constant names
  3625 This in general only affects hand-written proof tactics, simprocs and
  3626 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3627 Consider using @{const_name} antiquotation.
  3628 
  3629 * New class "default" with associated constant "default".
  3630 
  3631 * Function "sgn" is now overloaded and available on int, real, complex
  3632 (and other numeric types), using class "sgn".  Two possible defs of
  3633 sgn are given as equational assumptions in the classes sgn_if and
  3634 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3635 INCOMPATIBILITY.
  3636 
  3637 * Locale "partial_order" now unified with class "order" (cf. theory
  3638 Orderings), added parameter "less".  INCOMPATIBILITY.
  3639 
  3640 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3641 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3642 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3643 
  3644 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3645 changed order of proof goals in instance proofs.
  3646 
  3647 * The transitivity reasoner for partial and linear orders is set up
  3648 for classes "order" and "linorder".  Instances of the reasoner are available
  3649 in all contexts importing or interpreting the corresponding locales.
  3650 Method "order" invokes the reasoner separately; the reasoner
  3651 is also integrated with the Simplifier as a solver.  Diagnostic
  3652 command 'print_orders' shows the available instances of the reasoner
  3653 in the current context.
  3654 
  3655 * Localized monotonicity predicate in theory "Orderings"; integrated
  3656 lemmas max_of_mono and min_of_mono with this predicate.
  3657 INCOMPATIBILITY.
  3658 
  3659 * Formulation of theorem "dense" changed slightly due to integration
  3660 with new class dense_linear_order.
  3661 
  3662 * Uniform lattice theory development in HOL.
  3663 
  3664     constants "meet" and "join" now named "inf" and "sup"
  3665     constant "Meet" now named "Inf"
  3666 
  3667     classes "meet_semilorder" and "join_semilorder" now named
  3668       "lower_semilattice" and "upper_semilattice"
  3669     class "lorder" now named "lattice"
  3670     class "comp_lat" now named "complete_lattice"
  3671 
  3672     Instantiation of lattice classes allows explicit definitions
  3673     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3674 
  3675   INCOMPATIBILITY.  Theorem renames:
  3676 
  3677     meet_left_le            ~> inf_le1
  3678     meet_right_le           ~> inf_le2
  3679     join_left_le            ~> sup_ge1
  3680     join_right_le           ~> sup_ge2
  3681     meet_join_le            ~> inf_sup_ord
  3682     le_meetI                ~> le_infI
  3683     join_leI                ~> le_supI
  3684     le_meet                 ~> le_inf_iff
  3685     le_join                 ~> ge_sup_conv
  3686     meet_idempotent         ~> inf_idem
  3687     join_idempotent         ~> sup_idem
  3688     meet_comm               ~> inf_commute
  3689     join_comm               ~> sup_commute
  3690     meet_leI1               ~> le_infI1
  3691     meet_leI2               ~> le_infI2
  3692     le_joinI1               ~> le_supI1
  3693     le_joinI2               ~> le_supI2
  3694     meet_assoc              ~> inf_assoc
  3695     join_assoc              ~> sup_assoc
  3696     meet_left_comm          ~> inf_left_commute
  3697     meet_left_idempotent    ~> inf_left_idem
  3698     join_left_comm          ~> sup_left_commute
  3699     join_left_idempotent    ~> sup_left_idem
  3700     meet_aci                ~> inf_aci
  3701     join_aci                ~> sup_aci
  3702     le_def_meet             ~> le_iff_inf
  3703     le_def_join             ~> le_iff_sup
  3704     join_absorp2            ~> sup_absorb2
  3705     join_absorp1            ~> sup_absorb1
  3706     meet_absorp1            ~> inf_absorb1
  3707     meet_absorp2            ~> inf_absorb2
  3708     meet_join_absorp        ~> inf_sup_absorb
  3709     join_meet_absorp        ~> sup_inf_absorb
  3710     distrib_join_le         ~> distrib_sup_le
  3711     distrib_meet_le         ~> distrib_inf_le
  3712 
  3713     add_meet_distrib_left   ~> add_inf_distrib_left
  3714     add_join_distrib_left   ~> add_sup_distrib_left
  3715     is_join_neg_meet        ~> is_join_neg_inf
  3716     is_meet_neg_join        ~> is_meet_neg_sup
  3717     add_meet_distrib_right  ~> add_inf_distrib_right
  3718     add_join_distrib_right  ~> add_sup_distrib_right
  3719     add_meet_join_distribs  ~> add_sup_inf_distribs
  3720     join_eq_neg_meet        ~> sup_eq_neg_inf
  3721     meet_eq_neg_join        ~> inf_eq_neg_sup
  3722     add_eq_meet_join        ~> add_eq_inf_sup
  3723     meet_0_imp_0            ~> inf_0_imp_0
  3724     join_0_imp_0            ~> sup_0_imp_0
  3725     meet_0_eq_0             ~> inf_0_eq_0
  3726     join_0_eq_0             ~> sup_0_eq_0
  3727     neg_meet_eq_join        ~> neg_inf_eq_sup
  3728     neg_join_eq_meet        ~> neg_sup_eq_inf
  3729     join_eq_if              ~> sup_eq_if
  3730 
  3731     mono_meet               ~> mono_inf
  3732     mono_join               ~> mono_sup
  3733     meet_bool_eq            ~> inf_bool_eq
  3734     join_bool_eq            ~> sup_bool_eq
  3735     meet_fun_eq             ~> inf_fun_eq
  3736     join_fun_eq             ~> sup_fun_eq
  3737     meet_set_eq             ~> inf_set_eq
  3738     join_set_eq             ~> sup_set_eq
  3739     meet1_iff               ~> inf1_iff
  3740     meet2_iff               ~> inf2_iff
  3741     meet1I                  ~> inf1I
  3742     meet2I                  ~> inf2I
  3743     meet1D1                 ~> inf1D1
  3744     meet2D1                 ~> inf2D1
  3745     meet1D2                 ~> inf1D2
  3746     meet2D2                 ~> inf2D2
  3747     meet1E                  ~> inf1E
  3748     meet2E                  ~> inf2E
  3749     join1_iff               ~> sup1_iff
  3750     join2_iff               ~> sup2_iff
  3751     join1I1                 ~> sup1I1
  3752     join2I1                 ~> sup2I1
  3753     join1I1                 ~> sup1I1
  3754     join2I2                 ~> sup1I2
  3755     join1CI                 ~> sup1CI
  3756     join2CI                 ~> sup2CI
  3757     join1E                  ~> sup1E
  3758     join2E                  ~> sup2E
  3759 
  3760     is_meet_Meet            ~> is_meet_Inf
  3761     Meet_bool_def           ~> Inf_bool_def
  3762     Meet_fun_def            ~> Inf_fun_def
  3763     Meet_greatest           ~> Inf_greatest
  3764     Meet_lower              ~> Inf_lower
  3765     Meet_set_def            ~> Inf_set_def
  3766 
  3767     Sup_def                 ~> Sup_Inf
  3768     Sup_bool_eq             ~> Sup_bool_def
  3769     Sup_fun_eq              ~> Sup_fun_def
  3770     Sup_set_eq              ~> Sup_set_def
  3771 
  3772     listsp_meetI            ~> listsp_infI
  3773     listsp_meet_eq          ~> listsp_inf_eq
  3774 
  3775     meet_min                ~> inf_min
  3776     join_max                ~> sup_max
  3777 
  3778 * Added syntactic class "size"; overloaded constant "size" now has
  3779 type "'a::size ==> bool"
  3780 
  3781 * Internal reorganisation of `size' of datatypes: size theorems
  3782 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3783 simplification rules by default!); theorems "prod.size" now named
  3784 "*.size".
  3785 
  3786 * Class "div" now inherits from class "times" rather than "type".
  3787 INCOMPATIBILITY.
  3788 
  3789 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  3790 Linorder etc.  have disappeared; operations defined in terms of
  3791 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  3792 
  3793 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  3794 
  3795 * HOL-Word: New extensive library and type for generic, fixed size
  3796 machine words, with arithemtic, bit-wise, shifting and rotating
  3797 operations, reflection into int, nat, and bool lists, automation for
  3798 linear arithmetic (by automatic reflection into nat or int), including
  3799 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  3800 arithmetic type classes, supporting automatic simplification of
  3801 numerals on all operations.
  3802 
  3803 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  3804 
  3805 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  3806 
  3807 * Code generator library theories:
  3808   - Code_Integer represents HOL integers by big integer literals in target
  3809     languages.
  3810   - Code_Char represents HOL characters by character literals in target
  3811     languages.
  3812   - Code_Char_chr like Code_Char, but also offers treatment of character
  3813     codes; includes Code_Integer.
  3814   - Executable_Set allows to generate code for finite sets using lists.
  3815   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  3816     denominator).
  3817   - Executable_Real implements a subset of real numbers, namly those
  3818     representable by rational numbers.
  3819   - Efficient_Nat implements natural numbers by integers, which in general will
  3820     result in higher efficency; pattern matching with 0/Suc is eliminated;
  3821     includes Code_Integer.
  3822   - Code_Index provides an additional datatype index which is mapped to
  3823     target-language built-in integers.
  3824   - Code_Message provides an additional datatype message_string which is isomorphic to
  3825     strings; messages are mapped to target-language strings.
  3826 
  3827 * New package for inductive predicates
  3828 
  3829   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  3830 
  3831     inductive
  3832       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3833       for z_1 :: U_1 and ... and z_n :: U_m
  3834     where
  3835       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3836     | ...
  3837 
  3838   with full support for type-inference, rather than
  3839 
  3840     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3841 
  3842     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3843     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3844 
  3845     inductive "s z_1 ... z_m"
  3846     intros
  3847       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3848       ...
  3849 
  3850   For backward compatibility, there is a wrapper allowing inductive
  3851   sets to be defined with the new package via
  3852 
  3853     inductive_set
  3854       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3855       for z_1 :: U_1 and ... and z_n :: U_m
  3856     where
  3857       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3858     | ...
  3859 
  3860   or
  3861 
  3862     inductive_set
  3863       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3864       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3865       for z_1 :: U_1 and ... and z_n :: U_m
  3866     where
  3867       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3868     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3869     | ...
  3870 
  3871   if the additional syntax "p ..." is required.
  3872 
  3873   Numerous examples can be found in the subdirectories src/HOL/Auth,
  3874   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  3875 
  3876   INCOMPATIBILITIES:
  3877 
  3878   - Since declaration and definition of inductive sets or predicates
  3879     is no longer separated, abbreviations involving the newly
  3880     introduced sets or predicates must be specified together with the
  3881     introduction rules after the 'where' keyword (see above), rather
  3882     than before the actual inductive definition.
  3883 
  3884   - The variables in induction and elimination rules are now
  3885     quantified in the order of their occurrence in the introduction
  3886     rules, rather than in alphabetical order. Since this may break
  3887     some proofs, these proofs either have to be repaired, e.g. by
  3888     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  3889     statements of the form
  3890 
  3891       case (rule_i a_i_1 ... a_i_{k_i})
  3892 
  3893     or the old order of quantification has to be restored by explicitly adding
  3894     meta-level quantifiers in the introduction rules, i.e.
  3895 
  3896       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  3897 
  3898   - The format of the elimination rules is now
  3899 
  3900       p z_1 ... z_m x_1 ... x_n ==>
  3901         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3902         ==> ... ==> P
  3903 
  3904     for predicates and
  3905 
  3906       (x_1, ..., x_n) : s z_1 ... z_m ==>
  3907         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3908         ==> ... ==> P
  3909 
  3910     for sets rather than
  3911 
  3912       x : s z_1 ... z_m ==>
  3913         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  3914         ==> ... ==> P
  3915 
  3916     This may require terms in goals to be expanded to n-tuples
  3917     (e.g. using case_tac or simplification with the split_paired_all
  3918     rule) before the above elimination rule is applicable.
  3919 
  3920   - The elimination or case analysis rules for (mutually) inductive
  3921     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  3922     list of rules "p_1_..._p_k.elims" is no longer available.
  3923 
  3924 * New package "function"/"fun" for general recursive functions,
  3925 supporting mutual and nested recursion, definitions in local contexts,
  3926 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  3927 for small examples, and the separate tutorial on the function
  3928 package. The old recdef "package" is still available as before, but
  3929 users are encouraged to use the new package.
  3930 
  3931 * Method "lexicographic_order" automatically synthesizes termination
  3932 relations as lexicographic combinations of size measures. 
  3933 
  3934 * Case-expressions allow arbitrary constructor-patterns (including
  3935 "_") and take their order into account, like in functional
  3936 programming.  Internally, this is translated into nested
  3937 case-expressions; missing cases are added and mapped to the predefined
  3938 constant "undefined". In complicated cases printing may no longer show
  3939 the original input but the internal form. Lambda-abstractions allow
  3940 the same form of pattern matching: "% pat1 => e1 | ..." is an
  3941 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  3942 variable.
  3943 
  3944 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  3945 is an abbreviation for "of_nat :: nat => int". The simplification
  3946 rules for "of_nat" have been changed to work like "int" did
  3947 previously.  Potential INCOMPATIBILITY:
  3948   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  3949   - of_nat_diff and of_nat_mult are no longer default simp rules
  3950 
  3951 * Method "algebra" solves polynomial equations over (semi)rings using
  3952 Groebner bases. The (semi)ring structure is defined by locales and the
  3953 tool setup depends on that generic context. Installing the method for
  3954 a specific type involves instantiating the locale and possibly adding
  3955 declarations for computation on the coefficients.  The method is
  3956 already instantiated for natural numbers and for the axiomatic class
  3957 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  3958 CALCULEMUS 2007 for the general principles underlying this
  3959 architecture of context-aware proof-tools.
  3960 
  3961 * Method "ferrack" implements quantifier elimination over
  3962 special-purpose dense linear orders using locales (analogous to
  3963 "algebra"). The method is already installed for class
  3964 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  3965 rat, etc.
  3966 
  3967 * Former constant "List.op @" now named "List.append".  Use ML
  3968 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  3969 circumvent possible incompatibilities when working on ML level.
  3970 
  3971 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  3972 
  3973 * New function listsum :: 'a list => 'a for arbitrary monoids.
  3974 Special syntax: "SUM x <- xs. f x" (and latex variants)
  3975 
  3976 * New syntax for Haskell-like list comprehension (input only), eg.
  3977 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  3978 
  3979 * The special syntax for function "filter" has changed from [x :
  3980 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  3981 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  3982 
  3983 * [a..b] is now defined for arbitrary linear orders.  It used to be
  3984 defined on nat only, as an abbreviation for [a..<Suc b]
  3985 INCOMPATIBILITY.
  3986 
  3987 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  3988 
  3989 * New functions "sorted" and "sort" in src/HOL/List.thy.
  3990 
  3991 * New lemma collection field_simps (an extension of ring_simps) for
  3992 manipulating (in)equations involving division. Multiplies with all
  3993 denominators that can be proved to be non-zero (in equations) or
  3994 positive/negative (in inequations).
  3995 
  3996 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  3997 have been improved and renamed to ring_simps, group_simps and
  3998 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  3999 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4000 
  4001 * Theory Library/Commutative_Ring: switched from recdef to function
  4002 package; constants add, mul, pow now curried.  Infix syntax for
  4003 algebraic operations.
  4004 
  4005 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4006 INCOMPATIBILITY.
  4007 
  4008 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4009 INCOMPATIBILITY.
  4010 
  4011 * HOL/records: generalised field-update to take a function on the
  4012 field rather than the new value: r(|A := x|) is translated to A_update
  4013 (K x) r The K-combinator that is internally used is called K_record.
  4014 INCOMPATIBILITY: Usage of the plain update functions has to be
  4015 adapted.
  4016  
  4017 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4018 * x = 0, which are required for a semiring.  Richer structures do not
  4019 inherit from semiring_0 anymore, because this property is a theorem
  4020 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4021 there is more to prove, but this is mostly trivial.
  4022 
  4023 * Class "recpower" is generalized to arbitrary monoids, not just
  4024 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4025 commutativity or semiring properties additionally.
  4026 
  4027 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4028 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4029 better use 'abbreviation'.
  4030 
  4031 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4032 
  4033 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4034 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4035 significant changes for setting up numeral syntax for types:
  4036   - New constants Numeral.pred and Numeral.succ instead
  4037       of former Numeral.bin_pred and Numeral.bin_succ.
  4038   - Use integer operations instead of bin_add, bin_mult and so on.
  4039   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4040   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4041 
  4042 See src/HOL/Integ/IntArith.thy for an example setup.
  4043 
  4044 * Command 'normal_form' computes the normal form of a term that may
  4045 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4046 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4047 heavy-duty computations because the functions are compiled to ML
  4048 first.  Correspondingly, a method "normalization" is provided.  See
  4049 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4050 
  4051 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4052 25 like -->); output depends on the "iff" print_mode, the default is
  4053 "A = B" (with priority 50).
  4054 
  4055 * Relations less (<) and less_eq (<=) are also available on type bool.
  4056 Modified syntax to disallow nesting without explicit parentheses,
  4057 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4058 INCOMPATIBILITY.
  4059 
  4060 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4061 
  4062 * Relation composition operator "op O" now has precedence 75 and binds
  4063 stronger than union and intersection. INCOMPATIBILITY.
  4064 
  4065 * The old set interval syntax "{m..n(}" (and relatives) has been
  4066 removed.  Use "{m..<n}" (and relatives) instead.
  4067 
  4068 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4069 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4070 ``declare [[simproc del: neq]]''.
  4071 
  4072 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4073 True/False.
  4074 
  4075 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4076 
  4077 * Theorem setsum_mult renamed to setsum_right_distrib.
  4078 
  4079 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4080 ``rule'' method.
  4081 
  4082 * Reimplemented methods "sat" and "satx", with several improvements:
  4083 goals no longer need to be stated as "<prems> ==> False", equivalences
  4084 (i.e. "=" on type bool) are handled, variable names of the form
  4085 "lit_<n>" are no longer reserved, significant speedup.
  4086 
  4087 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4088 zChaff is still supported as well.
  4089 
  4090 * 'inductive' and 'datatype': provide projections of mutual rules,
  4091 bundled as foo_bar.inducts;
  4092 
  4093 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4094 Library.
  4095 
  4096 * Library: moved theory Accessible_Part to main HOL.
  4097 
  4098 * Library: added theory Coinductive_List of potentially infinite lists
  4099 as greatest fixed-point.
  4100 
  4101 * Library: added theory AssocList which implements (finite) maps as
  4102 association lists.
  4103 
  4104 * Method "evaluation" solves goals (i.e. a boolean expression)
  4105 efficiently by compiling it to ML.  The goal is "proved" (via an
  4106 oracle) if it evaluates to True.
  4107 
  4108 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4109 also when invoked by the simplifier.  This results in the Simplifier
  4110 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4111 Configuration option fast_arith_split_limit=0 recovers the old
  4112 behavior.
  4113 
  4114 * Support for hex (0x20) and binary (0b1001) numerals.
  4115 
  4116 * New method: reify eqs (t), where eqs are equations for an
  4117 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4118 parameter, computes a term s::'b and a list xs::'a list and proves the
  4119 theorem I xs s = t. This is also known as reification or quoting. The
  4120 resulting theorem is applied to the subgoal to substitute t with I xs
  4121 s.  If t is omitted, the subgoal itself is reified.
  4122 
  4123 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4124 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4125 where f is supposed to be a computable function (in the sense of code
  4126 generattion). The method uses reify to compute s and xs as above then
  4127 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4128 r and finally gets the theorem t = r, which is again applied to the
  4129 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4130 
  4131 * Reflection: Automatic reification now handels binding, an example is
  4132 available in src/HOL/ex/ReflectionEx.thy
  4133 
  4134 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4135 command 'statespace' that is similar to 'record', but introduces an
  4136 abstract specification based on the locale infrastructure instead of
  4137 HOL types.  This leads to extra flexibility in composing state spaces,
  4138 in particular multiple inheritance and renaming of components.
  4139 
  4140 
  4141 *** HOL-Complex ***
  4142 
  4143 * Hyperreal: Functions root and sqrt are now defined on negative real
  4144 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4145 Nonnegativity side conditions have been removed from many lemmas, so
  4146 that more subgoals may now be solved by simplification; potential
  4147 INCOMPATIBILITY.
  4148 
  4149 * Real: new type classes formalize real normed vector spaces and
  4150 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4151 and norm :: 'a => real.
  4152 
  4153 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4154 reals into other types. The overloaded constant Reals :: 'a set is now
  4155 defined as range of_real; potential INCOMPATIBILITY.
  4156 
  4157 * Real: proper support for ML code generation, including 'quickcheck'.
  4158 Reals are implemented as arbitrary precision rationals.
  4159 
  4160 * Hyperreal: Several constants that previously worked only for the
  4161 reals have been generalized, so they now work over arbitrary vector
  4162 spaces. Type annotations may need to be added in some cases; potential
  4163 INCOMPATIBILITY.
  4164 
  4165   Infinitesimal  :: ('a::real_normed_vector) star set
  4166   HFinite        :: ('a::real_normed_vector) star set
  4167   HInfinite      :: ('a::real_normed_vector) star set
  4168   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4169   monad          :: ('a::real_normed_vector) star => 'a star set
  4170   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4171   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4172   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4173   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4174   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4175   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4176   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4177   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4178   sgn            :: 'a::real_normed_vector => 'a
  4179   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4180 
  4181 * Complex: Some complex-specific constants are now abbreviations for
  4182 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4183 hnorm.  Other constants have been entirely removed in favor of the
  4184 polymorphic versions (INCOMPATIBILITY):
  4185 
  4186   approx        <-- capprox
  4187   HFinite       <-- CFinite
  4188   HInfinite     <-- CInfinite
  4189   Infinitesimal <-- CInfinitesimal
  4190   monad         <-- cmonad
  4191   galaxy        <-- cgalaxy
  4192   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4193   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4194   (ns)deriv     <-- (ns)cderiv
  4195 
  4196 
  4197 *** HOL-Algebra ***
  4198 
  4199 * Formalisation of ideals and the quotient construction over rings.
  4200 
  4201 * Order and lattice theory no longer based on records.
  4202 INCOMPATIBILITY.
  4203 
  4204 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4205 greatest_closed.  INCOMPATIBILITY.
  4206 
  4207 * Method algebra is now set up via an attribute.  For examples see
  4208 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4209 of algebraic structures.
  4210 
  4211 * Renamed theory CRing to Ring.
  4212 
  4213 
  4214 *** HOL-Nominal ***
  4215 
  4216 * Substantial, yet incomplete support for nominal datatypes (binding
  4217 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4218 src/HOL/Nominal/Examples.  Prospective users should consult
  4219 http://isabelle.in.tum.de/nominal/
  4220 
  4221 
  4222 *** ML ***
  4223 
  4224 * ML basics: just one true type int, which coincides with IntInf.int
  4225 (even on SML/NJ).
  4226 
  4227 * ML within Isar: antiquotations allow to embed statically-checked
  4228 formal entities in the source, referring to the context available at
  4229 compile-time.  For example:
  4230 
  4231 ML {* @{sort "{zero,one}"} *}
  4232 ML {* @{typ "'a => 'b"} *}
  4233 ML {* @{term "%x. x"} *}
  4234 ML {* @{prop "x == y"} *}
  4235 ML {* @{ctyp "'a => 'b"} *}
  4236 ML {* @{cterm "%x. x"} *}
  4237 ML {* @{cprop "x == y"} *}
  4238 ML {* @{thm asm_rl} *}
  4239 ML {* @{thms asm_rl} *}
  4240 ML {* @{type_name c} *}
  4241 ML {* @{type_syntax c} *}
  4242 ML {* @{const_name c} *}
  4243 ML {* @{const_syntax c} *}
  4244 ML {* @{context} *}
  4245 ML {* @{theory} *}
  4246 ML {* @{theory Pure} *}
  4247 ML {* @{theory_ref} *}
  4248 ML {* @{theory_ref Pure} *}
  4249 ML {* @{simpset} *}
  4250 ML {* @{claset} *}
  4251 ML {* @{clasimpset} *}
  4252 
  4253 The same works for sources being ``used'' within an Isar context.
  4254 
  4255 * ML in Isar: improved error reporting; extra verbosity with
  4256 ML_Context.trace enabled.
  4257 
  4258 * Pure/General/table.ML: the join operations now works via exceptions
  4259 DUP/SAME instead of type option. This is simpler in simple cases, and
  4260 admits slightly more efficient complex applications.
  4261 
  4262 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4263 use Context.generic instead of just theory.
  4264 
  4265 * Pure: datatype Context.generic joins theory/Proof.context and
  4266 provides some facilities for code that works in either kind of
  4267 context, notably GenericDataFun for uniform theory and proof data.
  4268 
  4269 * Pure: simplified internal attribute type, which is now always
  4270 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4271 local (Proof.context) attributes have been discontinued, while
  4272 minimizing code duplication. Thm.rule_attribute and
  4273 Thm.declaration_attribute build canonical attributes; see also structure
  4274 Context for further operations on Context.generic, notably
  4275 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4276 declarations and definitions.
  4277 
  4278 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4279 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4280 init only required for impure data. INCOMPATIBILITY: empty really need
  4281 to be empty (no dependencies on theory content!)
  4282 
  4283 * Pure/kernel: consts certification ignores sort constraints given in
  4284 signature declarations. (This information is not relevant to the
  4285 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4286 potential INCOMPATIBILITY.
  4287 
  4288 * Pure: axiomatic type classes are now purely definitional, with
  4289 explicit proofs of class axioms and super class relations performed
  4290 internally. See Pure/axclass.ML for the main internal interfaces --
  4291 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4292 AxClass.axiomatize_class/classrel/arity supersede
  4293 Sign.add_classes/classrel/arities.
  4294 
  4295 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4296 global/local versions on theory vs. Proof.context have been
  4297 discontinued; Attrib.syntax and Method.syntax have been adapted
  4298 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4299 attributes, methods, etc.
  4300 
  4301 * Pure: several functions of signature "... -> theory -> theory * ..."
  4302 have been reoriented to "... -> theory -> ... * theory" in order to
  4303 allow natural usage in combination with the ||>, ||>>, |-> and
  4304 fold_map combinators.
  4305 
  4306 * Pure: official theorem names (closed derivations) and additional
  4307 comments (tags) are now strictly separate.  Name hints -- which are
  4308 maintained as tags -- may be attached any time without affecting the
  4309 derivation.
  4310 
  4311 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4312 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4313 achieve the old behaviour.
  4314 
  4315 * Pure: the "Goal" constant is now called "prop", supporting a
  4316 slightly more general idea of ``protecting'' meta-level rule
  4317 statements.
  4318 
  4319 * Pure: Logic.(un)varify only works in a global context, which is now
  4320 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4321 Logic.legacy_(un)varify as temporary workaround.
  4322 
  4323 * Pure: structure Name provides scalable operations for generating
  4324 internal variable names, notably Name.variants etc.  This replaces
  4325 some popular functions from term.ML:
  4326 
  4327   Term.variant		->  Name.variant
  4328   Term.variantlist	->  Name.variant_list
  4329   Term.invent_names	->  Name.invent_list
  4330 
  4331 Note that low-level renaming rarely occurs in new code -- operations
  4332 from structure Variable are used instead (see below).
  4333 
  4334 * Pure: structure Variable provides fundamental operations for proper
  4335 treatment of fixed/schematic variables in a context.  For example,
  4336 Variable.import introduces fixes for schematics of given facts and
  4337 Variable.export reverses the effect (up to renaming) -- this replaces
  4338 various freeze_thaw operations.
  4339 
  4340 * Pure: structure Goal provides simple interfaces for
  4341 init/conclude/finish and tactical prove operations (replacing former
  4342 Tactic.prove).  Goal.prove is the canonical way to prove results
  4343 within a given context; Goal.prove_global is a degraded version for
  4344 theory level goals, including a global Drule.standard.  Note that
  4345 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4346 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4347 in a locale context).
  4348 
  4349 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4350 and type checking (Syntax.check_term etc.), with common combinations
  4351 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4352 which are considered legacy and await removal.
  4353 
  4354 * Pure/Syntax: generic interfaces for type unchecking
  4355 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4356 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4357 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4358 available for convenience, but refer to the very same operations using
  4359 a mere theory instead of a full context.
  4360 
  4361 * Isar: simplified treatment of user-level errors, using exception
  4362 ERROR of string uniformly.  Function error now merely raises ERROR,
  4363 without any side effect on output channels.  The Isar toplevel takes
  4364 care of proper display of ERROR exceptions.  ML code may use plain
  4365 handle/can/try; cat_error may be used to concatenate errors like this:
  4366 
  4367   ... handle ERROR msg => cat_error msg "..."
  4368 
  4369 Toplevel ML code (run directly or through the Isar toplevel) may be
  4370 embedded into the Isar toplevel with exception display/debug like
  4371 this:
  4372 
  4373   Isar.toplevel (fn () => ...)
  4374 
  4375 INCOMPATIBILITY, removed special transform_error facilities, removed
  4376 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4377 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4378 -- use plain ERROR instead.
  4379 
  4380 * Isar: theory setup now has type (theory -> theory), instead of a
  4381 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4382 
  4383 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4384 ProofContext.debug/verbose flags.
  4385 
  4386 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4387 theory before entering a proof state.  Transactions now always see a
  4388 quasi-functional intermediate checkpoint, both in interactive and
  4389 batch mode.
  4390 
  4391 * Isar: simplified interfaces for outer syntax.  Renamed
  4392 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4393 OuterSyntax.add_parsers -- this functionality is now included in
  4394 OuterSyntax.command etc.  INCOMPATIBILITY.
  4395 
  4396 * Simplifier: the simpset of a running simplification process now
  4397 contains a proof context (cf. Simplifier.the_context), which is the
  4398 very context that the initial simpset has been retrieved from (by
  4399 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4400 (solver, looper etc.) may depend on arbitrary proof data.
  4401 
  4402 * Simplifier.inherit_context inherits the proof context (plus the
  4403 local bounds) of the current simplification process; any simproc
  4404 etc. that calls the Simplifier recursively should do this!  Removed
  4405 former Simplifier.inherit_bounds, which is already included here --
  4406 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4407 specify an explicit context using Simplifier.context/theory_context.
  4408 
  4409 * Simplifier/Classical Reasoner: more abstract interfaces
  4410 change_simpset/claset for modifying the simpset/claset reference of a
  4411 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4412 INCOMPATIBILITY.
  4413 
  4414 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4415 "Trueprop" etc.
  4416 
  4417 
  4418 *** System ***
  4419 
  4420 * settings: the default heap location within ISABELLE_HOME_USER now
  4421 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4422 Isabelle installations.
  4423 
  4424 * isabelle-process: option -S (secure mode) disables some critical
  4425 operations, notably runtime compilation and evaluation of ML source
  4426 code.
  4427 
  4428 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4429 
  4430 * Support for parallel execution, using native multicore support of
  4431 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4432 independent theories, according to the given theory header
  4433 specifications. The maximum number of worker threads is specified via
  4434 usedir option -M or the "max-threads" setting in Proof General. A
  4435 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4436 to 6 on a 8-core machine.  User-code needs to observe certain
  4437 guidelines for thread-safe programming, see appendix A in the Isar
  4438 Implementation manual.
  4439 
  4440 
  4441 
  4442 New in Isabelle2005 (October 2005)
  4443 ----------------------------------
  4444 
  4445 *** General ***
  4446 
  4447 * Theory headers: the new header syntax for Isar theories is
  4448 
  4449   theory <name>
  4450   imports <theory1> ... <theoryN>
  4451   uses <file1> ... <fileM>
  4452   begin
  4453 
  4454 where the 'uses' part is optional.  The previous syntax
  4455 
  4456   theory <name> = <theory1> + ... + <theoryN>:
  4457 
  4458 will disappear in the next release.  Use isatool fixheaders to convert
  4459 existing theory files.  Note that there is no change in ancient
  4460 non-Isar theories now, but these will disappear soon.
  4461 
  4462 * Theory loader: parent theories can now also be referred to via
  4463 relative and absolute paths.
  4464 
  4465 * Command 'find_theorems' searches for a list of criteria instead of a
  4466 list of constants. Known criteria are: intro, elim, dest, name:string,
  4467 simp:term, and any term. Criteria can be preceded by '-' to select
  4468 theorems that do not match. Intro, elim, dest select theorems that
  4469 match the current goal, name:s selects theorems whose fully qualified
  4470 name contain s, and simp:term selects all simplification rules whose
  4471 lhs match term.  Any other term is interpreted as pattern and selects
  4472 all theorems matching the pattern. Available in ProofGeneral under
  4473 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4474 
  4475   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4476 
  4477 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4478 matching the current goal as introduction rule and not having "HOL."
  4479 in their name (i.e. not being defined in theory HOL).
  4480 
  4481 * Command 'thms_containing' has been discontinued in favour of
  4482 'find_theorems'; INCOMPATIBILITY.
  4483 
  4484 * Communication with Proof General is now 8bit clean, which means that
  4485 Unicode text in UTF-8 encoding may be used within theory texts (both
  4486 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4487 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4488 
  4489   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4490   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4491 
  4492 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4493 Classical Reasoner.  Typical big applications run around 2 times
  4494 faster.
  4495 
  4496 
  4497 *** Document preparation ***
  4498 
  4499 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4500 of raw sources.  Only those symbols that do not require additional
  4501 LaTeX packages (depending on comments in isabellesym.sty) are
  4502 displayed properly, everything else is left verbatim.  isatool display
  4503 and isatool print are used as front ends (these are subject to the
  4504 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4505 
  4506 * Command tags control specific markup of certain regions of text,
  4507 notably folding and hiding.  Predefined tags include "theory" (for
  4508 theory begin and end), "proof" for proof commands, and "ML" for
  4509 commands involving ML code; the additional tags "visible" and
  4510 "invisible" are unused by default.  Users may give explicit tag
  4511 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4512 interpretation of tags is determined by the LaTeX job during document
  4513 preparation: see option -V of isatool usedir, or options -n and -t of
  4514 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4515 \isadroptag.
  4516 
  4517 Several document versions may be produced at the same time via isatool
  4518 usedir (the generated index.html will link all of them).  Typical
  4519 specifications include ''-V document=theory,proof,ML'' to present
  4520 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4521 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4522 these parts without any formal replacement text.  The Isabelle site
  4523 default settings produce ''document'' and ''outline'' versions as
  4524 specified above.
  4525 
  4526 * Several new antiquotations:
  4527 
  4528   @{term_type term} prints a term with its type annotated;
  4529 
  4530   @{typeof term} prints the type of a term;
  4531 
  4532   @{const const} is the same as @{term const}, but checks that the
  4533   argument is a known logical constant;
  4534 
  4535   @{term_style style term} and @{thm_style style thm} print a term or
  4536   theorem applying a "style" to it
  4537 
  4538   @{ML text}
  4539 
  4540 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4541 definitions, equations, inequations etc., 'concl' printing only the
  4542 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4543 to print the specified premise.  TermStyle.add_style provides an ML
  4544 interface for introducing further styles.  See also the "LaTeX Sugar"
  4545 document practical applications.  The ML antiquotation prints
  4546 type-checked ML expressions verbatim.
  4547 
  4548 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4549 and 'text' support optional locale specification '(in loc)', which
  4550 specifies the default context for interpreting antiquotations.  For
  4551 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4552 
  4553 * Option 'locale=NAME' of antiquotations specifies an alternative
  4554 context interpreting the subsequent argument.  For example: @{thm
  4555 [locale=lattice] inf_assoc}.
  4556 
  4557 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4558 a proof context.
  4559 
  4560 * Proper output of antiquotations for theory commands involving a
  4561 proof context (such as 'locale' or 'theorem (in loc) ...').
  4562 
  4563 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4564 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4565 
  4566 * isatool usedir: new option -C (default true) controls whether option
  4567 -D should include a copy of the original document directory; -C false
  4568 prevents unwanted effects such as copying of administrative CVS data.
  4569 
  4570 
  4571 *** Pure ***
  4572 
  4573 * Considerably improved version of 'constdefs' command.  Now performs
  4574 automatic type-inference of declared constants; additional support for
  4575 local structure declarations (cf. locales and HOL records), see also
  4576 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4577 sequential dependencies of definitions within a single 'constdefs'
  4578 section; moreover, the declared name needs to be an identifier.  If
  4579 all fails, consider to fall back on 'consts' and 'defs' separately.
  4580 
  4581 * Improved indexed syntax and implicit structures.  First of all,
  4582 indexed syntax provides a notational device for subscripted
  4583 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4584 expressions.  Secondly, in a local context with structure
  4585 declarations, number indexes \<^sub>n or the empty index (default
  4586 number 1) refer to a certain fixed variable implicitly; option
  4587 show_structs controls printing of implicit structures.  Typical
  4588 applications of these concepts involve record types and locales.
  4589 
  4590 * New command 'no_syntax' removes grammar declarations (and
  4591 translations) resulting from the given syntax specification, which is
  4592 interpreted in the same manner as for the 'syntax' command.
  4593 
  4594 * 'Advanced' translation functions (parse_translation etc.) may depend
  4595 on the signature of the theory context being presently used for
  4596 parsing/printing, see also isar-ref manual.
  4597 
  4598 * Improved 'oracle' command provides a type-safe interface to turn an
  4599 ML expression of type theory -> T -> term into a primitive rule of
  4600 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4601 is already included here); see also FOL/ex/IffExample.thy;
  4602 INCOMPATIBILITY.
  4603 
  4604 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4605 before); "cI" is no longer bound, use "c.intro" instead.
  4606 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4607 axclasses vs. locales.
  4608 
  4609 * Improved internal renaming of symbolic identifiers -- attach primes
  4610 instead of base 26 numbers.
  4611 
  4612 * New flag show_question_marks controls printing of leading question
  4613 marks in schematic variable names.
  4614 
  4615 * In schematic variable names, *any* symbol following \<^isub> or
  4616 \<^isup> is now treated as part of the base name.  For example, the
  4617 following works without printing of awkward ".0" indexes:
  4618 
  4619   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4620     by simp
  4621 
  4622 * Inner syntax includes (*(*nested*) comments*).
  4623 
  4624 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4625 annotations as "(00...)".
  4626 
  4627 * Clear separation of logical types and nonterminals, where the latter
  4628 may only occur in 'syntax' specifications or type abbreviations.
  4629 Before that distinction was only partially implemented via type class
  4630 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4631 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4632 exotic syntax specifications may require further adaption
  4633 (e.g. Cube/Cube.thy).
  4634 
  4635 * Removed obsolete type class "logic", use the top sort {} instead.
  4636 Note that non-logical types should be declared as 'nonterminals'
  4637 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4638 specifications.
  4639 
  4640 * Attributes 'induct' and 'cases': type or set names may now be
  4641 locally fixed variables as well.
  4642 
  4643 * Simplifier: can now control the depth to which conditional rewriting
  4644 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4645 Limit.
  4646 
  4647 * Simplifier: simplification procedures may now take the current
  4648 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4649 interface), which is very useful for calling the Simplifier
  4650 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4651 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4652 low-level mk_simproc no longer applies Logic.varify internally, to
  4653 allow for use in a context of fixed variables.
  4654 
  4655 * thin_tac now works even if the assumption being deleted contains !!
  4656 or ==>.  More generally, erule now works even if the major premise of
  4657 the elimination rule contains !! or ==>.
  4658 
  4659 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4660 
  4661 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4662 from Pure, which contains all common declarations already.  Both
  4663 theories are defined via plain Isabelle/Isar .thy files.
  4664 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4665 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4666 use isatool fixcpure to adapt your theory and ML sources.
  4667 
  4668 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4669 selections of theorems in named facts via index ranges.
  4670 
  4671 * 'print_theorems': in theory mode, really print the difference
  4672 wrt. the last state (works for interactive theory development only),
  4673 in proof mode print all local facts (cf. 'print_facts');
  4674 
  4675 * 'hide': option '(open)' hides only base names.
  4676 
  4677 * More efficient treatment of intermediate checkpoints in interactive
  4678 theory development.
  4679 
  4680 * Code generator is now invoked via code_module (incremental code
  4681 generation) and code_library (modular code generation, ML structures
  4682 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4683 must be quoted when used as identifiers.
  4684 
  4685 * New 'value' command for reading, evaluating and printing terms using
  4686 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4687 quoted when used as identifier.
  4688 
  4689 
  4690 *** Locales ***
  4691 
  4692 * New commands for the interpretation of locale expressions in
  4693 theories (1), locales (2) and proof contexts (3).  These generate
  4694 proof obligations from the expression specification.  After the
  4695 obligations have been discharged, theorems of the expression are added
  4696 to the theory, target locale or proof context.  The synopsis of the
  4697 commands is a follows:
  4698 
  4699   (1) interpretation expr inst
  4700   (2) interpretation target < expr
  4701   (3) interpret expr inst
  4702 
  4703 Interpretation in theories and proof contexts require a parameter
  4704 instantiation of terms from the current context.  This is applied to
  4705 specifications and theorems of the interpreted expression.
  4706 Interpretation in locales only permits parameter renaming through the
  4707 locale expression.  Interpretation is smart in that interpretations
  4708 that are active already do not occur in proof obligations, neither are
  4709 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4710 inspect active interpretations of a particular locale.  For details,
  4711 see the Isar Reference manual.  Examples can be found in
  4712 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4713 
  4714 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4715 'interpret' instead.
  4716 
  4717 * New context element 'constrains' for adding type constraints to
  4718 parameters.
  4719 
  4720 * Context expressions: renaming of parameters with syntax
  4721 redeclaration.
  4722 
  4723 * Locale declaration: 'includes' disallowed.
  4724 
  4725 * Proper static binding of attribute syntax -- i.e. types / terms /
  4726 facts mentioned as arguments are always those of the locale definition
  4727 context, independently of the context of later invocations.  Moreover,
  4728 locale operations (renaming and type / term instantiation) are applied
  4729 to attribute arguments as expected.
  4730 
  4731 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4732 actual attributes; rare situations may require Attrib.attribute to
  4733 embed those attributes into Attrib.src that lack concrete syntax.
  4734 Attribute implementations need to cooperate properly with the static
  4735 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4736 Attrib.XXX_thm etc. already do the right thing without further
  4737 intervention.  Only unusual applications -- such as "where" or "of"
  4738 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4739 on the context and the facts involved -- may have to assign parsed
  4740 values to argument tokens explicitly.
  4741 
  4742 * Changed parameter management in theorem generation for long goal
  4743 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4744 theorem statement in rare situations.
  4745 
  4746 * Locale inspection command 'print_locale' omits notes elements.  Use
  4747 'print_locale!' to have them included in the output.
  4748 
  4749 
  4750 *** Provers ***
  4751 
  4752 * Provers/hypsubst.ML: improved version of the subst method, for
  4753 single-step rewriting: it now works in bound variable contexts. New is
  4754 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4755 rewrite a different subterm than the original subst method, which is
  4756 still available as 'simplesubst'.
  4757 
  4758 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4759 and quasi orders.
  4760 
  4761 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4762 reflexive-transitive closure of relations.
  4763 
  4764 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4765 limit (previously hard-coded with a value of 20) user-definable.
  4766 
  4767 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4768 is peformed already.  Object-logics merely need to finish their
  4769 initial simpset configuration as before.  INCOMPATIBILITY.
  4770 
  4771 
  4772 *** HOL ***
  4773 
  4774 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4775 
  4776   syntax (epsilon)
  4777     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4778 
  4779 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4780 and x-symbol; use option '-m epsilon' to get it actually printed.
  4781 Moreover, the mathematically important symbolic identifier \<epsilon>
  4782 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4783 
  4784 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  4785 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  4786 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  4787 support corresponding Isar calculations.
  4788 
  4789 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  4790 instead of ":".
  4791 
  4792 * theory SetInterval: changed the syntax for open intervals:
  4793 
  4794   Old       New
  4795   {..n(}    {..<n}
  4796   {)n..}    {n<..}
  4797   {m..n(}   {m..<n}
  4798   {)m..n}   {m<..n}
  4799   {)m..n(}  {m<..<n}
  4800 
  4801 The old syntax is still supported but will disappear in the next
  4802 release.  For conversion use the following Emacs search and replace
  4803 patterns (these are not perfect but work quite well):
  4804 
  4805   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  4806   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  4807 
  4808 * Theory Commutative_Ring (in Library): method comm_ring for proving
  4809 equalities in commutative rings; method 'algebra' provides a generic
  4810 interface.
  4811 
  4812 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  4813 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  4814 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  4815 be a tuple pattern.
  4816 
  4817 Some new syntax forms are available:
  4818 
  4819   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  4820   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  4821   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  4822   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  4823 
  4824 The latter form "\<Sum>x < k. e" used to be based on a separate
  4825 function "Summation", which has been discontinued.
  4826 
  4827 * theory Finite_Set: in structured induction proofs, the insert case
  4828 is now 'case (insert x F)' instead of the old counterintuitive 'case
  4829 (insert F x)'.
  4830 
  4831 * The 'refute' command has been extended to support a much larger
  4832 fragment of HOL, including axiomatic type classes, constdefs and
  4833 typedefs, inductive datatypes and recursion.
  4834 
  4835 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  4836 Requires zChaff with proof generation to be installed.  See
  4837 HOL/ex/SAT_Examples.thy for examples.
  4838 
  4839 * Datatype induction via method 'induct' now preserves the name of the
  4840 induction variable. For example, when proving P(xs::'a list) by
  4841 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  4842 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  4843 in unstructured proof scripts.
  4844 
  4845 * Reworked implementation of records.  Improved scalability for
  4846 records with many fields, avoiding performance problems for type
  4847 inference. Records are no longer composed of nested field types, but
  4848 of nested extension types. Therefore the record type only grows linear
  4849 in the number of extensions and not in the number of fields.  The
  4850 top-level (users) view on records is preserved.  Potential
  4851 INCOMPATIBILITY only in strange cases, where the theory depends on the
  4852 old record representation. The type generated for a record is called
  4853 <record_name>_ext_type.
  4854 
  4855 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  4856 proofs triggered by a record definition or a simproc (if
  4857 quick_and_dirty is enabled).  Definitions of large records can take
  4858 quite long.
  4859 
  4860 New simproc record_upd_simproc for simplification of multiple record
  4861 updates enabled by default.  Moreover, trivial updates are also
  4862 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  4863 occasionally, since simplification is more powerful by default.
  4864 
  4865 * typedef: proper support for polymorphic sets, which contain extra
  4866 type-variables in the term.
  4867 
  4868 * Simplifier: automatically reasons about transitivity chains
  4869 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  4870 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  4871 old proofs break occasionally as simplification may now solve more
  4872 goals than previously.
  4873 
  4874 * Simplifier: converts x <= y into x = y if assumption y <= x is
  4875 present.  Works for all partial orders (class "order"), in particular
  4876 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  4877 just like y <= x.
  4878 
  4879 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  4880 bound variable or a constant then the let is unfolded.  Otherwise
  4881 first a is simplified to b, and then f b is simplified to g. If
  4882 possible we abstract b from g arriving at "let x = b in h x",
  4883 otherwise we unfold the let and arrive at g.  The simproc can be
  4884 enabled/disabled by the reference use_let_simproc.  Potential
  4885 INCOMPATIBILITY since simplification is more powerful by default.
  4886 
  4887 * Classical reasoning: the meson method now accepts theorems as arguments.
  4888 
  4889 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  4890 jobs to provide advice on the provability of subgoals.
  4891 
  4892 * Theory OrderedGroup and Ring_and_Field: various additions and
  4893 improvements to faciliate calculations involving equalities and
  4894 inequalities.
  4895 
  4896 The following theorems have been eliminated or modified
  4897 (INCOMPATIBILITY):
  4898 
  4899   abs_eq             now named abs_of_nonneg
  4900   abs_of_ge_0        now named abs_of_nonneg
  4901   abs_minus_eq       now named abs_of_nonpos
  4902   imp_abs_id         now named abs_of_nonneg
  4903   imp_abs_neg_id     now named abs_of_nonpos
  4904   mult_pos           now named mult_pos_pos
  4905   mult_pos_le        now named mult_nonneg_nonneg
  4906   mult_pos_neg_le    now named mult_nonneg_nonpos
  4907   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  4908   mult_neg           now named mult_neg_neg
  4909   mult_neg_le        now named mult_nonpos_nonpos
  4910 
  4911 * The following lemmas in Ring_and_Field have been added to the simplifier:
  4912      
  4913      zero_le_square
  4914      not_square_less_zero 
  4915 
  4916   The following lemmas have been deleted from Real/RealPow:
  4917   
  4918      realpow_zero_zero
  4919      realpow_two
  4920      realpow_less
  4921      zero_le_power
  4922      realpow_two_le
  4923      abs_realpow_two
  4924      realpow_two_abs     
  4925 
  4926 * Theory Parity: added rules for simplifying exponents.
  4927 
  4928 * Theory List:
  4929 
  4930 The following theorems have been eliminated or modified
  4931 (INCOMPATIBILITY):
  4932 
  4933   list_all_Nil       now named list_all.simps(1)
  4934   list_all_Cons      now named list_all.simps(2)
  4935   list_all_conv      now named list_all_iff
  4936   set_mem_eq         now named mem_iff
  4937 
  4938 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  4939 asymptotic "big O" calculations.  See the notes in BigO.thy.
  4940 
  4941 
  4942 *** HOL-Complex ***
  4943 
  4944 * Theory RealDef: better support for embedding natural numbers and
  4945 integers in the reals.
  4946 
  4947 The following theorems have been eliminated or modified
  4948 (INCOMPATIBILITY):
  4949 
  4950   exp_ge_add_one_self  now requires no hypotheses
  4951   real_of_int_add      reversed direction of equality (use [symmetric])
  4952   real_of_int_minus    reversed direction of equality (use [symmetric])
  4953   real_of_int_diff     reversed direction of equality (use [symmetric])
  4954   real_of_int_mult     reversed direction of equality (use [symmetric])
  4955 
  4956 * Theory RComplete: expanded support for floor and ceiling functions.
  4957 
  4958 * Theory Ln is new, with properties of the natural logarithm
  4959 
  4960 * Hyperreal: There is a new type constructor "star" for making
  4961 nonstandard types.  The old type names are now type synonyms:
  4962 
  4963   hypreal = real star
  4964   hypnat = nat star
  4965   hcomplex = complex star
  4966 
  4967 * Hyperreal: Many groups of similarly-defined constants have been
  4968 replaced by polymorphic versions (INCOMPATIBILITY):
  4969 
  4970   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  4971 
  4972   starset      <-- starsetNat, starsetC
  4973   *s*          <-- *sNat*, *sc*
  4974   starset_n    <-- starsetNat_n, starsetC_n
  4975   *sn*         <-- *sNatn*, *scn*
  4976   InternalSets <-- InternalNatSets, InternalCSets
  4977 
  4978   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  4979   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  4980   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  4981   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  4982   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  4983 
  4984 * Hyperreal: Many type-specific theorems have been removed in favor of
  4985 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  4986 
  4987   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  4988   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  4989   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  4990   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  4991   right_minus <-- hypreal_add_minus
  4992   left_minus <-- {hypreal,hcomplex}_add_minus_left
  4993   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  4994   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  4995   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  4996   mult_1_right <-- hcomplex_mult_one_right
  4997   mult_zero_left <-- hcomplex_mult_zero_left
  4998   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  4999   right_distrib <-- hypnat_add_mult_distrib2
  5000   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5001   right_inverse <-- hypreal_mult_inverse
  5002   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5003   order_refl <-- {hypreal,hypnat}_le_refl
  5004   order_trans <-- {hypreal,hypnat}_le_trans
  5005   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5006   order_less_le <-- {hypreal,hypnat}_less_le
  5007   linorder_linear <-- {hypreal,hypnat}_le_linear
  5008   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5009   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5010   add_nonneg_nonneg <-- hypreal_le_add_order
  5011 
  5012 * Hyperreal: Separate theorems having to do with type-specific
  5013 versions of constants have been merged into theorems that apply to the
  5014 new polymorphic constants (INCOMPATIBILITY):
  5015 
  5016   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5017   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5018   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5019   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5020   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5021   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5022   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5023   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5024   STAR_diff <-- {STAR,STARC}_diff
  5025   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5026     STARC_hcomplex_of_complex}_image_subset
  5027   starset_n_Un <-- starset{Nat,C}_n_Un
  5028   starset_n_Int <-- starset{Nat,C}_n_Int
  5029   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5030   starset_n_diff <-- starset{Nat,C}_n_diff
  5031   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5032   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5033   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5034   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5035   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5036   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5037   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5038   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5039   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5040   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5041   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5042   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5043   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5044   starfun_diff <-- starfun{C,RC,CR}_diff
  5045   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5046   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5047   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5048   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5049   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5050   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5051   starfun_Id <-- starfunC_Id
  5052   starfun_approx <-- starfun{Nat,CR}_approx
  5053   starfun_capprox <-- starfun{C,RC}_capprox
  5054   starfun_abs <-- starfunNat_rabs
  5055   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5056   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5057   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5058   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5059   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5060   starfun_add_approx <-- starfunCR_add_approx
  5061   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5062   starfun_divide <-- starfun{C,CR,RC}_divide
  5063   starfun_n <-- starfun{Nat,C}_n
  5064   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5065   starfun_n_add <-- starfun{Nat,C}_n_add
  5066   starfun_n_add_minus <-- starfunNat_n_add_minus
  5067   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5068   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5069   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5070 
  5071   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5072   star_n_minus <-- {hypreal,hcomplex}_minus
  5073   star_n_diff <-- {hypreal,hcomplex}_diff
  5074   star_n_mult <-- {hypreal,hcomplex}_mult
  5075   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5076   star_n_le <-- {hypreal,hypnat}_le
  5077   star_n_less <-- {hypreal,hypnat}_less
  5078   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5079   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5080   star_n_abs <-- hypreal_hrabs
  5081   star_n_divide <-- hcomplex_divide
  5082 
  5083   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5084   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5085   star_of_diff <-- hypreal_of_real_diff
  5086   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5087   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5088   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5089   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5090   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5091   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5092   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5093   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5094   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5095   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5096   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5097   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5098   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5099   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5100   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5101   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5102   star_of_power <-- hypreal_of_real_power
  5103   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5104 
  5105 * Hyperreal: new method "transfer" that implements the transfer
  5106 principle of nonstandard analysis. With a subgoal that mentions
  5107 nonstandard types like "'a star", the command "apply transfer"
  5108 replaces it with an equivalent one that mentions only standard types.
  5109 To be successful, all free variables must have standard types; non-
  5110 standard variables must have explicit universal quantifiers.
  5111 
  5112 * Hyperreal: A theory of Taylor series.
  5113 
  5114 
  5115 *** HOLCF ***
  5116 
  5117 * Discontinued special version of 'constdefs' (which used to support
  5118 continuous functions) in favor of the general Pure one with full
  5119 type-inference.
  5120 
  5121 * New simplification procedure for solving continuity conditions; it
  5122 is much faster on terms with many nested lambda abstractions (cubic
  5123 instead of exponential time).
  5124 
  5125 * New syntax for domain package: selector names are now optional.
  5126 Parentheses should be omitted unless argument is lazy, for example:
  5127 
  5128   domain 'a stream = cons "'a" (lazy "'a stream")
  5129 
  5130 * New command 'fixrec' for defining recursive functions with pattern
  5131 matching; defining multiple functions with mutual recursion is also
  5132 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5133 sinr, or any data constructor defined by the domain package. The given
  5134 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5135 syntax and examples.
  5136 
  5137 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5138 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5139 but the proof obligation additionally includes an admissibility
  5140 requirement. The packages generate instances of class cpo or pcpo,
  5141 with continuity and strictness theorems for Rep and Abs.
  5142 
  5143 * HOLCF: Many theorems have been renamed according to a more standard naming
  5144 scheme (INCOMPATIBILITY):
  5145 
  5146   foo_inject:  "foo$x = foo$y ==> x = y"
  5147   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5148   foo_less:    "(foo$x << foo$y) = (x << y)"
  5149   foo_strict:  "foo$UU = UU"
  5150   foo_defined: "... ==> foo$x ~= UU"
  5151   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5152 
  5153 
  5154 *** ZF ***
  5155 
  5156 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5157 including the First Isomorphism Theorem (on quotienting by the kernel
  5158 of a homomorphism).
  5159 
  5160 * ZF/Simplifier: install second copy of type solver that actually
  5161 makes use of TC rules declared to Isar proof contexts (or locales);
  5162 the old version is still required for ML proof scripts.
  5163 
  5164 
  5165 *** Cube ***
  5166 
  5167 * Converted to Isar theory format; use locales instead of axiomatic
  5168 theories.
  5169 
  5170 
  5171 *** ML ***
  5172 
  5173 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5174 for ||>, ||>>, |>>,
  5175 
  5176 * Pure/library.ML no longer defines its own option datatype, but uses
  5177 that of the SML basis, which has constructors NONE and SOME instead of
  5178 None and Some, as well as exception Option.Option instead of OPTION.
  5179 The functions the, if_none, is_some, is_none have been adapted
  5180 accordingly, while Option.map replaces apsome.
  5181 
  5182 * Pure/library.ML: the exception LIST has been given up in favour of
  5183 the standard exceptions Empty and Subscript, as well as
  5184 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5185 superceded by the standard hd and tl functions etc.
  5186 
  5187 A number of basic list functions are no longer exported to the ML
  5188 toplevel, as they are variants of predefined functions.  The following
  5189 suggests how one can translate existing code:
  5190 
  5191     rev_append xs ys = List.revAppend (xs, ys)
  5192     nth_elem (i, xs) = List.nth (xs, i)
  5193     last_elem xs = List.last xs
  5194     flat xss = List.concat xss
  5195     seq fs = List.app fs
  5196     partition P xs = List.partition P xs
  5197     mapfilter f xs = List.mapPartial f xs
  5198 
  5199 * Pure/library.ML: several combinators for linear functional
  5200 transformations, notably reverse application and composition:
  5201 
  5202   x |> f                f #> g
  5203   (x, y) |-> f          f #-> g
  5204 
  5205 * Pure/library.ML: introduced/changed precedence of infix operators:
  5206 
  5207   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5208   infix 2 ?;
  5209   infix 3 o oo ooo oooo;
  5210   infix 4 ~~ upto downto;
  5211 
  5212 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5213 infix operators.
  5214 
  5215 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5216 fold_map support linear functional transformations and nesting.  For
  5217 example:
  5218 
  5219   fold f [x1, ..., xN] y =
  5220     y |> f x1 |> ... |> f xN
  5221 
  5222   (fold o fold) f [xs1, ..., xsN] y =
  5223     y |> fold f xs1 |> ... |> fold f xsN
  5224 
  5225   fold f [x1, ..., xN] =
  5226     f x1 #> ... #> f xN
  5227 
  5228   (fold o fold) f [xs1, ..., xsN] =
  5229     fold f xs1 #> ... #> fold f xsN
  5230 
  5231 * Pure/library.ML: the following selectors on type 'a option are
  5232 available:
  5233 
  5234   the:               'a option -> 'a  (*partial*)
  5235   these:             'a option -> 'a  where 'a = 'b list
  5236   the_default: 'a -> 'a option -> 'a
  5237   the_list:          'a option -> 'a list
  5238 
  5239 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5240 basic operations for association lists, following natural argument
  5241 order; moreover the explicit equality predicate passed here avoids
  5242 potentially expensive polymorphic runtime equality checks.
  5243 The old functions may be expressed as follows:
  5244 
  5245   assoc = uncurry (AList.lookup (op =))
  5246   assocs = these oo AList.lookup (op =)
  5247   overwrite = uncurry (AList.update (op =)) o swap
  5248 
  5249 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5250 
  5251   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5252   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5253 
  5254 replacing make_keylist and keyfilter (occassionally used)
  5255 Naive rewrites:
  5256 
  5257   make_keylist = AList.make
  5258   keyfilter = AList.find (op =)
  5259 
  5260 * eq_fst and eq_snd now take explicit equality parameter, thus
  5261   avoiding eqtypes. Naive rewrites:
  5262 
  5263     eq_fst = eq_fst (op =)
  5264     eq_snd = eq_snd (op =)
  5265 
  5266 * Removed deprecated apl and apr (rarely used).
  5267   Naive rewrites:
  5268 
  5269     apl (n, op) =>>= curry op n
  5270     apr (op, m) =>>= fn n => op (n, m)
  5271 
  5272 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5273 provides a reasonably efficient light-weight implementation of sets as
  5274 lists.
  5275 
  5276 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5277 few new operations; existing lookup and update are now curried to
  5278 follow natural argument order (for use with fold etc.);
  5279 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5280 
  5281 * Pure/General: output via the Isabelle channels of
  5282 writeln/warning/error etc. is now passed through Output.output, with a
  5283 hook for arbitrary transformations depending on the print_mode
  5284 (cf. Output.add_mode -- the first active mode that provides a output
  5285 function wins).  Already formatted output may be embedded into further
  5286 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5287 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5288 accommodate easy composition of diagnostic messages etc.  Programmers
  5289 rarely need to care about Output.output or Output.raw at all, with
  5290 some notable exceptions: Output.output is required when bypassing the
  5291 standard channels (writeln etc.), or in token translations to produce
  5292 properly formatted results; Output.raw is required when capturing
  5293 already output material that will eventually be presented to the user
  5294 a second time.  For the default print mode, both Output.output and
  5295 Output.raw have no effect.
  5296 
  5297 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5298 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5299 cumulative results are displayed at the end of a batch session.
  5300 
  5301 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5302 replaced by File.platform_path and File.shell_path (with appropriate
  5303 hooks).  This provides a clean interface for unusual systems where the
  5304 internal and external process view of file names are different.
  5305 
  5306 * Pure: more efficient orders for basic syntactic entities: added
  5307 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5308 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5309 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5310 orders now -- potential INCOMPATIBILITY for code that depends on a
  5311 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5312 Library.sort_strings on result).
  5313 
  5314 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5315 fold_types traverse types/terms from left to right, observing natural
  5316 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5317 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5318 
  5319 * Pure: name spaces have been refined, with significant changes of the
  5320 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5321 to extern(_table).  The plain name entry path is superceded by a
  5322 general 'naming' context, which also includes the 'policy' to produce
  5323 a fully qualified name and external accesses of a fully qualified
  5324 name; NameSpace.extend is superceded by context dependent
  5325 Sign.declare_name.  Several theory and proof context operations modify
  5326 the naming context.  Especially note Theory.restore_naming and
  5327 ProofContext.restore_naming to get back to a sane state; note that
  5328 Theory.add_path is no longer sufficient to recover from
  5329 Theory.absolute_path in particular.
  5330 
  5331 * Pure: new flags short_names (default false) and unique_names
  5332 (default true) for controlling output of qualified names.  If
  5333 short_names is set, names are printed unqualified.  If unique_names is
  5334 reset, the name prefix is reduced to the minimum required to achieve
  5335 the original result when interning again, even if there is an overlap
  5336 with earlier declarations.
  5337 
  5338 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5339 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5340 (useful for printing error messages).  INCOMPATIBILITY.
  5341 
  5342 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5343 Theory.theory are now identified, referring to the universal
  5344 Context.theory (see Pure/context.ML).  Actual signature and theory
  5345 content is managed as theory data.  The old code and interfaces were
  5346 spread over many files and structures; the new arrangement introduces
  5347 considerable INCOMPATIBILITY to gain more clarity:
  5348 
  5349   Context -- theory management operations (name, identity, inclusion,
  5350     parents, ancestors, merge, etc.), plus generic theory data;
  5351 
  5352   Sign -- logical signature and syntax operations (declaring consts,
  5353     types, etc.), plus certify/read for common entities;
  5354 
  5355   Theory -- logical theory operations (stating axioms, definitions,
  5356     oracles), plus a copy of logical signature operations (consts,
  5357     types, etc.); also a few basic management operations (Theory.copy,
  5358     Theory.merge, etc.)
  5359 
  5360 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5361 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5362 for convenience -- they merely return the theory.
  5363 
  5364 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5365 
  5366 * Pure: the Isar proof context type is already defined early in Pure
  5367 as Context.proof (note that ProofContext.context and Proof.context are
  5368 aliases, where the latter is the preferred name).  This enables other
  5369 Isabelle components to refer to that type even before Isar is present.
  5370 
  5371 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5372 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5373 any of these kinds.  For example, Sign.intern typeK is now
  5374 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5375 Theory.hide_types.  Also note that former
  5376 Theory.hide_classes/types/consts are now
  5377 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5378 internalize their arguments!  INCOMPATIBILITY.
  5379 
  5380 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5381 datatype thmref (with constructors Name and NameSelection) instead of
  5382 plain string -- INCOMPATIBILITY;
  5383 
  5384 * Pure: cases produced by proof methods specify options, where NONE
  5385 means to remove case bindings -- INCOMPATIBILITY in
  5386 (RAW_)METHOD_CASES.
  5387 
  5388 * Pure: the following operations retrieve axioms or theorems from a
  5389 theory node or theory hierarchy, respectively:
  5390 
  5391   Theory.axioms_of: theory -> (string * term) list
  5392   Theory.all_axioms_of: theory -> (string * term) list
  5393   PureThy.thms_of: theory -> (string * thm) list
  5394   PureThy.all_thms_of: theory -> (string * thm) list
  5395 
  5396 * Pure: print_tac now outputs the goal through the trace channel.
  5397 
  5398 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5399 Reference Toplevel.debug (default false) controls detailed printing
  5400 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5401 controls execution profiling -- set to 1 for time and 2 for space
  5402 (both increase the runtime).
  5403 
  5404 * Isar session: The initial use of ROOT.ML is now always timed,
  5405 i.e. the log will show the actual process times, in contrast to the
  5406 elapsed wall-clock time that the outer shell wrapper produces.
  5407 
  5408 * Simplifier: improved handling of bound variables (nameless
  5409 representation, avoid allocating new strings).  Simprocs that invoke
  5410 the Simplifier recursively should use Simplifier.inherit_bounds to
  5411 avoid local name clashes.  Failure to do so produces warnings
  5412 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5413 for further details.
  5414 
  5415 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5416 bindings for all theorems stored within a given theory; this may help
  5417 in porting non-Isar theories to Isar ones, while keeping ML proof
  5418 scripts for the time being.
  5419 
  5420 * ML operator HTML.with_charset specifies the charset begin used for
  5421 generated HTML files.  For example:
  5422 
  5423   HTML.with_charset "utf-8" use_thy "Hebrew";
  5424   HTML.with_charset "utf-8" use_thy "Chinese";
  5425 
  5426 
  5427 *** System ***
  5428 
  5429 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5430 isabelle, isatool etc.).
  5431 
  5432 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5433 isatool doc, isatool mkdir, display_drafts etc.).
  5434 
  5435 * isatool usedir: option -f allows specification of the ML file to be
  5436 used by Isabelle; default is ROOT.ML.
  5437 
  5438 * New isatool version outputs the version identifier of the Isabelle
  5439 distribution being used.
  5440 
  5441 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5442 (containing Boolean satisfiability problems) into Isabelle/HOL
  5443 theories.
  5444 
  5445 
  5446 
  5447 New in Isabelle2004 (April 2004)
  5448 --------------------------------
  5449 
  5450 *** General ***
  5451 
  5452 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5453   Replaces linorder.ML.
  5454 
  5455 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5456   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5457   (\<a>...\<z>), are now considered normal letters, and can therefore
  5458   be used anywhere where an ASCII letter (a...zA...Z) has until
  5459   now. COMPATIBILITY: This obviously changes the parsing of some
  5460   terms, especially where a symbol has been used as a binder, say
  5461   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5462   as an identifier.  Fix it by inserting a space around former
  5463   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5464   existing theory and ML files.
  5465 
  5466 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5467 
  5468 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5469   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5470   a normal (but invisible) letter. For multiple letter subscripts repeat
  5471   \<^isub> like this: x\<^isub>1\<^isub>2.
  5472 
  5473 * Pure: There are now sub-/superscripts that can span more than one
  5474   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5475   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5476   superscript. The new control characters are not identifier parts.
  5477 
  5478 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5479   content of "..." to the latex file instead of \isacntrl... . The "..."
  5480   may consist of any printable characters excluding the end bracket >.
  5481 
  5482 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5483   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5484   declare constants "final", which prevents their being given a definition
  5485   later.  It is useful for constants whose behaviour is fixed axiomatically
  5486   rather than definitionally, such as the meta-logic connectives.
  5487 
  5488 * Pure: 'instance' now handles general arities with general sorts
  5489   (i.e. intersections of classes),
  5490 
  5491 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5492   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5493   It can be changed to alter the colors/layout of generated pages.
  5494 
  5495 
  5496 *** Isar ***
  5497 
  5498 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5499   cut_tac, subgoal_tac and thin_tac:
  5500   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5501     locales are no longer forced to write Isar proof scripts.
  5502     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5503     emulations.
  5504   - INCOMPATIBILITY: names of variables to be instantiated may no
  5505     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5506     This is consistent with the instantiation attribute "where".
  5507 
  5508 * Attributes "where" and "of":
  5509   - Now take type variables of instantiated theorem into account when reading
  5510     the instantiation string.  This fixes a bug that caused instantiated
  5511     theorems to have too special types in some circumstances.
  5512   - "where" permits explicit instantiations of type variables.
  5513 
  5514 * Calculation commands "moreover" and "also" no longer interfere with
  5515   current facts ("this"), admitting arbitrary combinations with "then"
  5516   and derived forms.
  5517 
  5518 * Locales:
  5519   - Goal statements involving the context element "includes" no longer
  5520     generate theorems with internal delta predicates (those ending on
  5521     "_axioms") in the premise.
  5522     Resolve particular premise with <locale>.intro to obtain old form.
  5523   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5524     specification and "includes" elements in goal statement.
  5525   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5526     [intro?] and [elim?] (respectively) by default.
  5527   - Experimental command for instantiation of locales in proof contexts:
  5528         instantiate <label>[<attrs>]: <loc>
  5529     Instantiates locale <loc> and adds all its theorems to the current context
  5530     taking into account their attributes.  Label and attrs are optional
  5531     modifiers, like in theorem declarations.  If present, names of
  5532     instantiated theorems are qualified with <label>, and the attributes
  5533     <attrs> are applied after any attributes these theorems might have already.
  5534       If the locale has assumptions, a chained fact of the form
  5535     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5536     are derived.  The command does not support old-style locales declared
  5537     with "locale (open)".
  5538       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5539 
  5540 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5541   (Isar) contexts.
  5542 
  5543 
  5544 *** HOL ***
  5545 
  5546 * Proof import: new image HOL4 contains the imported library from
  5547   the HOL4 system with about 2500 theorems. It is imported by
  5548   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5549   can be used like any other Isabelle image.  See
  5550   HOL/Import/HOL/README for more information.
  5551 
  5552 * Simplifier:
  5553   - Much improved handling of linear and partial orders.
  5554     Reasoners for linear and partial orders are set up for type classes
  5555     "linorder" and "order" respectively, and are added to the default simpset
  5556     as solvers.  This means that the simplifier can build transitivity chains
  5557     to solve goals from the assumptions.
  5558   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5559     of blast or auto after simplification become unnecessary because the goal
  5560     is solved by simplification already.
  5561 
  5562 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5563     all proved in axiomatic type classes for semirings, rings and fields.
  5564 
  5565 * Numerics:
  5566   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5567     now formalized using the Ring_and_Field theory mentioned above.
  5568   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5569     than before, because now they are set up once in a generic manner.
  5570   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5571     Look for the general versions in Ring_and_Field (and Power if they concern
  5572     exponentiation).
  5573 
  5574 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5575 
  5576 * Records:
  5577   - Record types are now by default printed with their type abbreviation
  5578     instead of the list of all field types. This can be configured via
  5579     the reference "print_record_type_abbr".
  5580   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5581     (not enabled by default).
  5582   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5583     EX x. x = sel r to True (not enabled by default).
  5584   - Tactic "record_split_simp_tac" to split and simplify records added.
  5585 
  5586 * 'specification' command added, allowing for definition by
  5587   specification.  There is also an 'ax_specification' command that
  5588   introduces the new constants axiomatically.
  5589 
  5590 * arith(_tac) is now able to generate counterexamples for reals as well.
  5591 
  5592 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5593 
  5594 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5595   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5596 
  5597 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5598   matrix theory to linear programming.
  5599 
  5600 * Unions and Intersections:
  5601   The latex output syntax of UN and INT has been changed
  5602   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5603   i.e. the index formulae has become a subscript.
  5604   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5605 
  5606 * Unions and Intersections over Intervals:
  5607   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5608   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5609   like in normal math, and corresponding versions for < and for intersection.
  5610 
  5611 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5612   lexicographic dictonary ordering has been added as "lexord".
  5613 
  5614 * ML: the legacy theory structures Int and List have been removed. They had
  5615   conflicted with ML Basis Library structures having the same names.
  5616 
  5617 * 'refute' command added to search for (finite) countermodels.  Only works
  5618   for a fragment of HOL.  The installation of an external SAT solver is
  5619   highly recommended.  See "HOL/Refute.thy" for details.
  5620 
  5621 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5622   formulae under an assignment of free variables to random values.
  5623   In contrast to 'refute', it can deal with inductive datatypes,
  5624   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5625   for examples.
  5626 
  5627 
  5628 *** HOLCF ***
  5629 
  5630 * Streams now come with concatenation and are part of the HOLCF image
  5631 
  5632 
  5633 
  5634 New in Isabelle2003 (May 2003)
  5635 ------------------------------
  5636 
  5637 *** General ***
  5638 
  5639 * Provers/simplifier:
  5640 
  5641   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5642     Assumptions are now subject to complete mutual simplification,
  5643     not just from left to right. The simplifier now preserves
  5644     the order of assumptions.
  5645 
  5646     Potential INCOMPATIBILITY:
  5647 
  5648     -- simp sometimes diverges where the old version did
  5649        not, e.g. invoking simp on the goal
  5650 
  5651         [| P (f x); y = x; f x = f y |] ==> Q
  5652 
  5653        now gives rise to the infinite reduction sequence
  5654 
  5655         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5656 
  5657        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5658        kind of problem.
  5659 
  5660     -- Tactics combining classical reasoner and simplification (such as auto)
  5661        are also affected by this change, because many of them rely on
  5662        simp. They may sometimes diverge as well or yield a different numbers
  5663        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5664        in case of problems. Sometimes subsequent calls to the classical
  5665        reasoner will fail because a preceeding call to the simplifier too
  5666        eagerly simplified the goal, e.g. deleted redundant premises.
  5667 
  5668   - The simplifier trace now shows the names of the applied rewrite rules
  5669 
  5670   - You can limit the number of recursive invocations of the simplifier
  5671     during conditional rewriting (where the simplifie tries to solve the
  5672     conditions before applying the rewrite rule):
  5673     ML "simp_depth_limit := n"
  5674     where n is an integer. Thus you can force termination where previously
  5675     the simplifier would diverge.
  5676 
  5677   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5678 
  5679   - No longer aborts on failed congruence proof.  Instead, the
  5680     congruence is ignored.
  5681 
  5682 * Pure: New generic framework for extracting programs from constructive
  5683   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5684   as HOL/Extraction for some case studies.
  5685 
  5686 * Pure: The main goal of the proof state is no longer shown by default, only
  5687 the subgoals. This behaviour is controlled by a new flag.
  5688    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5689 (ML: Proof.show_main_goal).
  5690 
  5691 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5692 rules whose conclusion matches subgoal 1:
  5693       PG menu: Isabelle/Isar -> Show me -> matching rules
  5694 The rules are ordered by how closely they match the subgoal.
  5695 In particular, rules that solve a subgoal outright are displayed first
  5696 (or rather last, the way they are printed).
  5697 (ML: ProofGeneral.print_intros())
  5698 
  5699 * Pure: New flag trace_unify_fail causes unification to print
  5700 diagnostic information (PG: in trace buffer) when it fails. This is
  5701 useful for figuring out why single step proofs like rule, erule or
  5702 assumption failed.
  5703 
  5704 * Pure: Locale specifications now produce predicate definitions
  5705 according to the body of text (covering assumptions modulo local
  5706 definitions); predicate "loc_axioms" covers newly introduced text,
  5707 while "loc" is cumulative wrt. all included locale expressions; the
  5708 latter view is presented only on export into the global theory
  5709 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5710 on the old view without predicates;
  5711 
  5712 * Pure: predefined locales "var" and "struct" are useful for sharing
  5713 parameters (as in CASL, for example); just specify something like
  5714 ``var x + var y + struct M'' as import;
  5715 
  5716 * Pure: improved thms_containing: proper indexing of facts instead of
  5717 raw theorems; check validity of results wrt. current name space;
  5718 include local facts of proof configuration (also covers active
  5719 locales), cover fixed variables in index; may use "_" in term
  5720 specification; an optional limit for the number of printed facts may
  5721 be given (the default is 40);
  5722 
  5723 * Pure: disallow duplicate fact bindings within new-style theory files
  5724 (batch-mode only);
  5725 
  5726 * Provers: improved induct method: assumptions introduced by case
  5727 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5728 the goal statement); "foo" still refers to all facts collectively;
  5729 
  5730 * Provers: the function blast.overloaded has been removed: all constants
  5731 are regarded as potentially overloaded, which improves robustness in exchange
  5732 for slight decrease in efficiency;
  5733 
  5734 * Provers/linorder: New generic prover for transitivity reasoning over
  5735 linear orders.  Note: this prover is not efficient!
  5736 
  5737 * Isar: preview of problems to finish 'show' now produce an error
  5738 rather than just a warning (in interactive mode);
  5739 
  5740 
  5741 *** HOL ***
  5742 
  5743 * arith(_tac)
  5744 
  5745  - Produces a counter example if it cannot prove a goal.
  5746    Note that the counter example may be spurious if the goal is not a formula
  5747    of quantifier-free linear arithmetic.
  5748    In ProofGeneral the counter example appears in the trace buffer.
  5749 
  5750  - Knows about div k and mod k where k is a numeral of type nat or int.
  5751 
  5752  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5753    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5754    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5755 
  5756 * simp's arithmetic capabilities have been enhanced a bit: it now
  5757 takes ~= in premises into account (by performing a case split);
  5758 
  5759 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5760 are distributed over a sum of terms;
  5761 
  5762 * New tactic "trans_tac" and method "trans" instantiate
  5763 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5764 "<=", "<" and "=").
  5765 
  5766 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5767 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5768 
  5769 * 'typedef' command has new option "open" to suppress the set
  5770 definition;
  5771 
  5772 * functions Min and Max on finite sets have been introduced (theory
  5773 Finite_Set);
  5774 
  5775 * attribute [symmetric] now works for relations as well; it turns
  5776 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5777 
  5778 * induct over a !!-quantified statement (say !!x1..xn):
  5779   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5780 
  5781 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5782 %x. None. Warning: empty_def now refers to the previously hidden definition
  5783 of the empty set.
  5784 
  5785 * Algebra: formalization of classical algebra.  Intended as base for
  5786 any algebraic development in Isabelle.  Currently covers group theory
  5787 (up to Sylow's theorem) and ring theory (Universal Property of
  5788 Univariate Polynomials).  Contributions welcome;
  5789 
  5790 * GroupTheory: deleted, since its material has been moved to Algebra;
  5791 
  5792 * Complex: new directory of the complex numbers with numeric constants,
  5793 nonstandard complex numbers, and some complex analysis, standard and
  5794 nonstandard (Jacques Fleuriot);
  5795 
  5796 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  5797 
  5798 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  5799 Fleuriot);
  5800 
  5801 * Real/HahnBanach: updated and adapted to locales;
  5802 
  5803 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  5804 Gray and Kramer);
  5805 
  5806 * UNITY: added the Meier-Sanders theory of progress sets;
  5807 
  5808 * MicroJava: bytecode verifier and lightweight bytecode verifier
  5809 as abstract algorithms, instantiated to the JVM;
  5810 
  5811 * Bali: Java source language formalization. Type system, operational
  5812 semantics, axiomatic semantics. Supported language features:
  5813 classes, interfaces, objects,virtual methods, static methods,
  5814 static/instance fields, arrays, access modifiers, definite
  5815 assignment, exceptions.
  5816 
  5817 
  5818 *** ZF ***
  5819 
  5820 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  5821 universe, etc.);
  5822 
  5823 * Main ZF: virtually all theories converted to new-style format;
  5824 
  5825 
  5826 *** ML ***
  5827 
  5828 * Pure: Tactic.prove provides sane interface for internal proofs;
  5829 omits the infamous "standard" operation, so this is more appropriate
  5830 than prove_goalw_cterm in many situations (e.g. in simprocs);
  5831 
  5832 * Pure: improved error reporting of simprocs;
  5833 
  5834 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  5835 up simprocs;
  5836 
  5837 
  5838 *** Document preparation ***
  5839 
  5840 * uses \par instead of \\ for line breaks in theory text. This may
  5841 shift some page breaks in large documents. To get the old behaviour
  5842 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  5843 
  5844 * minimized dependencies of isabelle.sty and isabellesym.sty on
  5845 other packages
  5846 
  5847 * \<euro> now needs package babel/greek instead of marvosym (which
  5848 broke \Rightarrow)
  5849 
  5850 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  5851 textcomp package)
  5852 
  5853 
  5854 
  5855 New in Isabelle2002 (March 2002)
  5856 --------------------------------
  5857 
  5858 *** Document preparation ***
  5859 
  5860 * greatly simplified document preparation setup, including more
  5861 graceful interpretation of isatool usedir -i/-d/-D options, and more
  5862 instructive isatool mkdir; users should basically be able to get
  5863 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  5864 users may run a separate document processing stage manually like this:
  5865 "isatool usedir -D output HOL Test && isatool document Test/output";
  5866 
  5867 * theory dependency graph may now be incorporated into documents;
  5868 isatool usedir -g true will produce session_graph.eps/.pdf for use
  5869 with \includegraphics of LaTeX;
  5870 
  5871 * proper spacing of consecutive markup elements, especially text
  5872 blocks after section headings;
  5873 
  5874 * support bold style (for single symbols only), input syntax is like
  5875 this: "\<^bold>\<alpha>" or "\<^bold>A";
  5876 
  5877 * \<bullet> is now output as bold \cdot by default, which looks much
  5878 better in printed text;
  5879 
  5880 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  5881 note that these symbols are currently unavailable in Proof General /
  5882 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  5883 
  5884 * isatool latex no longer depends on changed TEXINPUTS, instead
  5885 isatool document copies the Isabelle style files to the target
  5886 location;
  5887 
  5888 
  5889 *** Isar ***
  5890 
  5891 * Pure/Provers: improved proof by cases and induction;
  5892   - 'case' command admits impromptu naming of parameters (such as
  5893     "case (Suc n)");
  5894   - 'induct' method divinates rule instantiation from the inductive
  5895     claim; no longer requires excessive ?P bindings for proper
  5896     instantiation of cases;
  5897   - 'induct' method properly enumerates all possibilities of set/type
  5898     rules; as a consequence facts may be also passed through *type*
  5899     rules without further ado;
  5900   - 'induct' method now derives symbolic cases from the *rulified*
  5901     rule (before it used to rulify cases stemming from the internal
  5902     atomized version); this means that the context of a non-atomic
  5903     statement becomes is included in the hypothesis, avoiding the
  5904     slightly cumbersome show "PROP ?case" form;
  5905   - 'induct' may now use elim-style induction rules without chaining
  5906     facts, using ``missing'' premises from the goal state; this allows
  5907     rules stemming from inductive sets to be applied in unstructured
  5908     scripts, while still benefitting from proper handling of non-atomic
  5909     statements; NB: major inductive premises need to be put first, all
  5910     the rest of the goal is passed through the induction;
  5911   - 'induct' proper support for mutual induction involving non-atomic
  5912     rule statements (uses the new concept of simultaneous goals, see
  5913     below);
  5914   - append all possible rule selections, but only use the first
  5915     success (no backtracking);
  5916   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  5917   - undeclared rule case names default to numbers 1, 2, 3, ...;
  5918   - added 'print_induct_rules' (covered by help item in recent Proof
  5919     General versions);
  5920   - moved induct/cases attributes to Pure, methods to Provers;
  5921   - generic method setup instantiated for FOL and HOL;
  5922 
  5923 * Pure: support multiple simultaneous goal statements, for example
  5924 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  5925 meta-level mechanism, this acts as if several individual goals had
  5926 been stated separately; in particular common proof methods need to be
  5927 repeated in order to cover all claims; note that a single elimination
  5928 step is *not* sufficient to establish the two conjunctions, so this
  5929 fails:
  5930 
  5931   assume "A & B" then have A and B ..   (*".." fails*)
  5932 
  5933 better use "obtain" in situations as above; alternative refer to
  5934 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  5935 
  5936 * Pure: proper integration with ``locales''; unlike the original
  5937 version by Florian Kammller, Isar locales package high-level proof
  5938 contexts rather than raw logical ones (e.g. we admit to include
  5939 attributes everywhere); operations on locales include merge and
  5940 rename; support for implicit arguments (``structures''); simultaneous
  5941 type-inference over imports and text; see also HOL/ex/Locales.thy for
  5942 some examples;
  5943 
  5944 * Pure: the following commands have been ``localized'', supporting a
  5945 target locale specification "(in name)": 'lemma', 'theorem',
  5946 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  5947 stored both within the locale and at the theory level (exported and
  5948 qualified by the locale name);
  5949 
  5950 * Pure: theory goals may now be specified in ``long'' form, with
  5951 ad-hoc contexts consisting of arbitrary locale elements. for example
  5952 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  5953 definitions may be given, too); the result is a meta-level rule with
  5954 the context elements being discharged in the obvious way;
  5955 
  5956 * Pure: new proof command 'using' allows to augment currently used
  5957 facts after a goal statement ('using' is syntactically analogous to
  5958 'apply', but acts on the goal's facts only); this allows chained facts
  5959 to be separated into parts given before and after a claim, as in
  5960 ``from a and b have C using d and e <proof>'';
  5961 
  5962 * Pure: renamed "antecedent" case to "rule_context";
  5963 
  5964 * Pure: new 'judgment' command records explicit information about the
  5965 object-logic embedding (used by several tools internally); no longer
  5966 use hard-wired "Trueprop";
  5967 
  5968 * Pure: added 'corollary' command;
  5969 
  5970 * Pure: fixed 'token_translation' command;
  5971 
  5972 * Pure: removed obsolete 'exported' attribute;
  5973 
  5974 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  5975 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  5976 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  5977 
  5978 * Pure: method 'atomize' presents local goal premises as object-level
  5979 statements (atomic meta-level propositions); setup controlled via
  5980 rewrite rules declarations of 'atomize' attribute; example
  5981 application: 'induct' method with proper rule statements in improper
  5982 proof *scripts*;
  5983 
  5984 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  5985 now consider the syntactic context of assumptions, giving a better
  5986 chance to get type-inference of the arguments right (this is
  5987 especially important for locales);
  5988 
  5989 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  5990 mode;
  5991 
  5992 * Pure/obtain: the formal conclusion "thesis", being marked as
  5993 ``internal'', may no longer be reference directly in the text;
  5994 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  5995 situations;
  5996 
  5997 * Pure: generic 'sym' attribute which declares a rule both as pure
  5998 'elim?' and for the 'symmetric' operation;
  5999 
  6000 * Pure: marginal comments ``--'' may now occur just anywhere in the
  6001 text; the fixed correlation with particular command syntax has been
  6002 discontinued;
  6003 
  6004 * Pure: new method 'rules' is particularly well-suited for proof
  6005 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  6006 but often produces more compact proof terms with less detours;
  6007 
  6008 * Pure/Provers/classical: simplified integration with pure rule
  6009 attributes and methods; the classical "intro?/elim?/dest?"
  6010 declarations coincide with the pure ones; the "rule" method no longer
  6011 includes classically swapped intros; "intro" and "elim" methods no
  6012 longer pick rules from the context; also got rid of ML declarations
  6013 AddXIs/AddXEs/AddXDs; all of this has some potential for
  6014 INCOMPATIBILITY;
  6015 
  6016 * Provers/classical: attribute 'swapped' produces classical inversions
  6017 of introduction rules;
  6018 
  6019 * Provers/simplifier: 'simplified' attribute may refer to explicit
  6020 rules instead of full simplifier context; 'iff' attribute handles
  6021 conditional rules;
  6022 
  6023 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  6024 
  6025 * HOL: 'recdef' now fails on unfinished automated proofs, use
  6026 "(permissive)" option to recover old behavior;
  6027 
  6028 * HOL: 'inductive' no longer features separate (collective) attributes
  6029 for 'intros' (was found too confusing);
  6030 
  6031 * HOL: properly declared induction rules less_induct and
  6032 wf_induct_rule;
  6033 
  6034 
  6035 *** HOL ***
  6036 
  6037 * HOL: moved over to sane numeral syntax; the new policy is as
  6038 follows:
  6039 
  6040   - 0 and 1 are polymorphic constants, which are defined on any
  6041   numeric type (nat, int, real etc.);
  6042 
  6043   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  6044   binary representation internally;
  6045 
  6046   - type nat has special constructor Suc, and generally prefers Suc 0
  6047   over 1::nat and Suc (Suc 0) over 2::nat;
  6048 
  6049 This change may cause significant problems of INCOMPATIBILITY; here
  6050 are some hints on converting existing sources:
  6051 
  6052   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  6053   entities, so expressions involving "-" (unary or binary minus) need
  6054   to be spaced properly;
  6055 
  6056   - existing occurrences of "1" may need to be constraint "1::nat" or
  6057   even replaced by Suc 0; similar for old "2";
  6058 
  6059   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  6060 
  6061   - remove all special provisions on numerals in proofs;
  6062 
  6063 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  6064 representation (depends on bin_arith_simps in the default context);
  6065 
  6066 * HOL: symbolic syntax for x^2 (numeral 2);
  6067 
  6068 * HOL: the class of all HOL types is now called "type" rather than
  6069 "term"; INCOMPATIBILITY, need to adapt references to this type class
  6070 in axclass/classes, instance/arities, and (usually rare) occurrences
  6071 in typings (of consts etc.); internally the class is called
  6072 "HOL.type", ML programs should refer to HOLogic.typeS;
  6073 
  6074 * HOL/record package improvements:
  6075   - new derived operations "fields" to build a partial record section,
  6076     "extend" to promote a fixed record to a record scheme, and
  6077     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  6078     declared as simp by default;
  6079   - shared operations ("more", "fields", etc.) now need to be always
  6080     qualified) --- potential INCOMPATIBILITY;
  6081   - removed "make_scheme" operations (use "make" with "extend") --
  6082     INCOMPATIBILITY;
  6083   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  6084   - provides cases/induct rules for use with corresponding Isar
  6085     methods (for concrete records, record schemes, concrete more
  6086     parts, and schematic more parts -- in that order);
  6087   - internal definitions directly based on a light-weight abstract
  6088     theory of product types over typedef rather than datatype;
  6089 
  6090 * HOL: generic code generator for generating executable ML code from
  6091 specifications; specific support for HOL constructs such as inductive
  6092 datatypes and sets, as well as recursive functions; can be invoked
  6093 via 'generate_code' theory section;
  6094 
  6095 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  6096 
  6097 * HOL: consolidated and renamed several theories.  In particular:
  6098         Ord.thy has been absorbed into HOL.thy
  6099         String.thy has been absorbed into List.thy
  6100 
  6101 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  6102 (beware of argument permutation!);
  6103 
  6104 * HOL: linorder_less_split superseded by linorder_cases;
  6105 
  6106 * HOL/List: "nodups" renamed to "distinct";
  6107 
  6108 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  6109 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  6110   - Ex_def has changed, now need to use some_eq_ex
  6111 
  6112 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  6113 in this (rare) case use:
  6114 
  6115   delSWrapper "split_all_tac"
  6116   addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
  6117 
  6118 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
  6119 MAY FAIL;
  6120 
  6121 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
  6122 Isabelle's type classes, ^ on functions and relations has too general
  6123 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be
  6124 necessary to attach explicit type constraints;
  6125 
  6126 * HOL/Relation: the prefix name of the infix "O" has been changed from
  6127 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been
  6128 renamed accordingly (eg "compI" -> "rel_compI").
  6129 
  6130 * HOL: syntax translations now work properly with numerals and records
  6131 expressions;
  6132 
  6133 * HOL: bounded abstraction now uses syntax "%" / "\<lambda>" instead
  6134 of "lam" -- INCOMPATIBILITY;
  6135 
  6136 * HOL: got rid of some global declarations (potential INCOMPATIBILITY
  6137 for ML tools): const "()" renamed "Product_Type.Unity", type "unit"
  6138 renamed "Product_Type.unit";
  6139 
  6140 * HOL: renamed rtrancl_into_rtrancl2 to converse_rtrancl_into_rtrancl
  6141 
  6142 * HOL: removed obsolete theorem "optionE" (use "option.exhaust", or
  6143 the "cases" method);
  6144 
  6145 * HOL/GroupTheory: group theory examples including Sylow's theorem (by
  6146 Florian Kammller);
  6147 
  6148 * HOL/IMP: updated and converted to new-style theory format; several
  6149 parts turned into readable document, with proper Isar proof texts and
  6150 some explanations (by Gerwin Klein);
  6151 
  6152 * HOL-Real: added Complex_Numbers (by Gertrud Bauer);
  6153 
  6154 * HOL-Hyperreal is now a logic image;
  6155 
  6156 
  6157 *** HOLCF ***
  6158 
  6159 * Isar: consts/constdefs supports mixfix syntax for continuous
  6160 operations;
  6161 
  6162 * Isar: domain package adapted to new-style theory format, e.g. see
  6163 HOLCF/ex/Dnat.thy;
  6164 
  6165 * theory Lift: proper use of rep_datatype lift instead of ML hacks --
  6166 potential INCOMPATIBILITY; now use plain induct_tac instead of former
  6167 lift.induct_tac, always use UU instead of Undef;
  6168 
  6169 * HOLCF/IMP: updated and converted to new-style theory;
  6170 
  6171 
  6172 *** ZF ***
  6173 
  6174 * Isar: proper integration of logic-specific tools and packages,
  6175 including theory commands '(co)inductive', '(co)datatype',
  6176 'rep_datatype', 'inductive_cases', as well as methods 'ind_cases',
  6177 'induct_tac', 'case_tac', and 'typecheck' (with attribute 'TC');
  6178 
  6179 * theory Main no longer includes AC; for the Axiom of Choice, base
  6180 your theory on Main_ZFC;
  6181 
  6182 * the integer library now covers quotients and remainders, with many
  6183 laws relating division to addition, multiplication, etc.;
  6184 
  6185 * ZF/UNITY: Chandy and Misra's UNITY is now available in ZF, giving a
  6186 typeless version of the formalism;
  6187 
  6188 * ZF/AC, Coind, IMP, Resid: updated and converted to new-style theory
  6189 format;
  6190 
  6191 * ZF/Induct: new directory for examples of inductive definitions,
  6192 including theory Multiset for multiset orderings; converted to
  6193 new-style theory format;
  6194 
  6195 * ZF: many new theorems about lists, ordinals, etc.;
  6196 
  6197 
  6198 *** General ***
  6199 
  6200 * Pure/kernel: meta-level proof terms (by Stefan Berghofer); reference
  6201 variable proof controls level of detail: 0 = no proofs (only oracle
  6202 dependencies), 1 = lemma dependencies, 2 = compact proof terms; see
  6203 also ref manual for further ML interfaces;
  6204 
  6205 * Pure/axclass: removed obsolete ML interface
  6206 goal_subclass/goal_arity;
  6207 
  6208 * Pure/syntax: new token syntax "num" for plain numerals (without "#"
  6209 of "xnum"); potential INCOMPATIBILITY, since -0, -1 etc. are now
  6210 separate tokens, so expressions involving minus need to be spaced
  6211 properly;
  6212 
  6213 * Pure/syntax: support non-oriented infixes, using keyword "infix"
  6214 rather than "infixl" or "infixr";
  6215 
  6216 * Pure/syntax: concrete syntax for dummy type variables admits genuine
  6217 sort constraint specifications in type inference; e.g. "x::_::foo"
  6218 ensures that the type of "x" is of sort "foo" (but not necessarily a
  6219 type variable);
  6220 
  6221 * Pure/syntax: print modes "type_brackets" and "no_type_brackets"
  6222 control output of nested => (types); the default behavior is
  6223 "type_brackets";
  6224 
  6225 * Pure/syntax: builtin parse translation for "_constify" turns valued
  6226 tokens into AST constants;
  6227 
  6228 * Pure/syntax: prefer later declarations of translations and print
  6229 translation functions; potential INCOMPATIBILITY: need to reverse
  6230 multiple declarations for same syntax element constant;
  6231 
  6232 * Pure/show_hyps reset by default (in accordance to existing Isar
  6233 practice);
  6234 
  6235 * Provers/classical: renamed addaltern to addafter, addSaltern to