NEWS
author Cezary Kaliszyk <kaliszyk@in.tum.de>
Fri Oct 15 21:46:45 2010 +0900 (2010-10-15)
changeset 39994 7bd8013b903f
parent 39993 eebfa0b93896
child 40059 6ad9081665db
permissions -rw-r--r--
FSet: give names to respectfulness theorems, rename list_all2_refl to avoid clash
     1 Isabelle NEWS -- history user-relevant changes
     2 ==============================================
     3 
     4 New in this Isabelle version
     5 ----------------------------
     6 
     7 *** General ***
     8 
     9 * Explicit treatment of UTF8 sequences as Isabelle symbols, such that
    10 a Unicode character is treated as a single symbol, not a sequence of
    11 non-ASCII bytes as before.  Since Isabelle/ML string literals may
    12 contain symbols without further backslash escapes, Unicode can now be
    13 used here as well.  Recall that Symbol.explode in ML provides a
    14 consistent view on symbols, while raw explode (or String.explode)
    15 merely give a byte-oriented representation.
    16 
    17 * Theory loading: only the master source file is looked-up in the
    18 implicit load path, all other files are addressed relatively to its
    19 directory.  Minor INCOMPATIBILITY, subtle change in semantics.
    20 
    21 * Special treatment of ML file names has been discontinued.
    22 Historically, optional extensions .ML or .sml were added on demand --
    23 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
    24 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
    25 
    26 * Various options that affect pretty printing etc. are now properly
    27 handled within the context via configuration options, instead of
    28 unsynchronized references.  There are both ML Config.T entities and
    29 Isar declaration attributes to access these.
    30 
    31   ML (Config.T)                 Isar (attribute)
    32 
    33   eta_contract                  eta_contract
    34   show_brackets                 show_brackets
    35   show_sorts                    show_sorts
    36   show_types                    show_types
    37   show_question_marks           show_question_marks
    38   show_consts                   show_consts
    39 
    40   Syntax.ambiguity_level        syntax_ambiguity_level
    41 
    42   Goal_Display.goals_limit      goals_limit
    43   Goal_Display.show_main_goal   show_main_goal
    44 
    45   Thy_Output.display            thy_output_display
    46   Thy_Output.quotes             thy_output_quotes
    47   Thy_Output.indent             thy_output_indent
    48   Thy_Output.source             thy_output_source
    49   Thy_Output.break              thy_output_break
    50 
    51 Note that corresponding "..._default" references in ML may be only
    52 changed globally at the ROOT session setup, but *not* within a theory.
    53 
    54 
    55 *** Pure ***
    56 
    57 * Interpretation command 'interpret' accepts a list of equations like
    58 'interpretation' does.
    59 
    60 * Diagnostic command 'print_interps' prints interpretations in proofs
    61 in addition to interpretations in theories.
    62 
    63 * Discontinued obsolete 'global' and 'local' commands to manipulate
    64 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
    65 Sign.root_path and Sign.local_path may be applied directly where this
    66 feature is still required for historical reasons.
    67 
    68 * Discontinued ancient 'constdefs' command.  INCOMPATIBILITY, use
    69 'definition' instead.
    70 
    71 * Document antiquotations @{class} and @{type} for printing classes
    72 and type constructors.
    73 
    74 
    75 *** HOL ***
    76 
    77 * Predicates `distinct` and `sorted` now defined inductively, with nice
    78 induction rules.  INCOMPATIBILITY: former distinct.simps and sorted.simps
    79 now named distinct_simps and sorted_simps.
    80 
    81 * Constant `contents` renamed to `the_elem`, to free the generic name
    82 contents for other uses.  INCOMPATIBILITY.
    83 
    84 * Dropped old primrec package.  INCOMPATIBILITY.
    85 
    86 * Improved infrastructure for term evaluation using code generator
    87 techniques, in particular static evaluation conversions.
    88 
    89 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
    90  
    91 * Renamed lemmas:
    92   expand_fun_eq -> fun_eq_iff
    93   expand_set_eq -> set_eq_iff
    94   set_ext -> set_eqI
    95  INCOMPATIBILITY.
    96 
    97 * Renamed class eq and constant eq (for code generation) to class equal
    98 and constant equal, plus renaming of related facts and various tuning.
    99 INCOMPATIBILITY.
   100 
   101 * Scala (2.8 or higher) has been added to the target languages of
   102 the code generator.
   103 
   104 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   105 
   106 * Removed output syntax "'a ~=> 'b" for "'a => 'b option". INCOMPATIBILITY.
   107 
   108 * Theory SetsAndFunctions has been split into Function_Algebras and Set_Algebras;
   109 canonical names for instance definitions for functions; various improvements.
   110 INCOMPATIBILITY.
   111 
   112 * Records: logical foundation type for records do not carry a '_type' suffix
   113 any longer.  INCOMPATIBILITY.
   114 
   115 * Code generation for records: more idiomatic representation of record types.
   116 Warning: records are not covered by ancient SML code generation any longer.
   117 INCOMPATIBILITY.  In cases of need, a suitable rep_datatype declaration
   118 helps to succeed then:
   119 
   120   record 'a foo = ...
   121   ...
   122   rep_datatype foo_ext ...
   123 
   124 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   125 INCOMPATIBILITY.
   126 
   127 * Quickcheck in locales considers interpretations of that locale for
   128 counter example search.
   129 
   130 * Theory Library/Monad_Syntax provides do-syntax for monad types.  Syntax
   131 in Library/State_Monad has been changed to avoid ambiguities.
   132 INCOMPATIBILITY.
   133 
   134 * Code generator: export_code without explicit file declaration prints
   135 to standard output.  INCOMPATIBILITY.
   136 
   137 * Abolished symbol type names:  "prod" and "sum" replace "*" and "+"
   138 respectively.  INCOMPATIBILITY.
   139 
   140 * Constant "split" has been merged with constant "prod_case";  names
   141 of ML functions, facts etc. involving split have been retained so far,
   142 though.  INCOMPATIBILITY.
   143 
   144 * Dropped old infix syntax "mem" for List.member;  use "in set"
   145 instead.  INCOMPATIBILITY.
   146 
   147 * Refactoring of code-generation specific operations in List.thy
   148 
   149   constants
   150     null ~> List.null
   151 
   152   facts
   153     mem_iff ~> member_def
   154     null_empty ~> null_def
   155 
   156 INCOMPATIBILITY.  Note that these were not suppossed to be used
   157 regularly unless for striking reasons;  their main purpose was code
   158 generation.
   159 
   160 * Some previously unqualified names have been qualified:
   161 
   162   types
   163     bool ~> HOL.bool
   164     nat ~> Nat.nat
   165 
   166   constants
   167     Trueprop ~> HOL.Trueprop
   168     True ~> HOL.True
   169     False ~> HOL.False
   170     op & ~> HOL.conj
   171     op | ~> HOL.disj
   172     op --> ~> HOL.implies
   173     op = ~> HOL.eq
   174     Not ~> HOL.Not
   175     The ~> HOL.The
   176     All ~> HOL.All
   177     Ex ~> HOL.Ex
   178     Ex1 ~> HOL.Ex1
   179     Let ~> HOL.Let
   180     If ~> HOL.If
   181     Ball ~> Set.Ball
   182     Bex ~> Set.Bex
   183     Suc ~> Nat.Suc
   184     Pair ~> Product_Type.Pair
   185     fst ~> Product_Type.fst
   186     snd ~> Product_Type.snd
   187     curry ~> Product_Type.curry
   188     op : ~> Set.member
   189     Collect ~> Set.Collect
   190 
   191 INCOMPATIBILITY.
   192 
   193 * Removed simplifier congruence rule of "prod_case", as has for long
   194 been the case with "split".  INCOMPATIBILITY.
   195 
   196 * Datatype package: theorems generated for executable equality
   197 (class eq) carry proper names and are treated as default code
   198 equations.
   199 
   200 * Removed lemma Option.is_none_none (Duplicate of is_none_def).
   201 INCOMPATIBILITY.
   202 
   203 * List.thy: use various operations from the Haskell prelude when
   204 generating Haskell code.
   205 
   206 * Multiset.thy: renamed empty_idemp -> empty_neutral
   207 
   208 * code_simp.ML and method code_simp: simplification with rules determined
   209 by code generator.
   210 
   211 * code generator: do not print function definitions for case
   212 combinators any longer.
   213 
   214 * Multivariate Analysis: Introduced a type class for euclidean space. Most
   215 theorems are now stated in terms of euclidean spaces instead of finite
   216 cartesian products.
   217 
   218   types
   219     real ^ 'n ~>  'a::real_vector
   220               ~>  'a::euclidean_space
   221               ~>  'a::ordered_euclidean_space
   222         (depends on your needs)
   223 
   224   constants
   225      _ $ _        ~> _ $$ _
   226      \<chi> x. _  ~> \<chi>\<chi> x. _
   227      CARD('n)     ~> DIM('a)
   228 
   229 Also note that the indices are now natural numbers and not from some finite
   230 type. Finite cartesian products of euclidean spaces, products of euclidean
   231 spaces the real and complex numbers are instantiated to be euclidean_spaces.
   232 
   233 INCOMPATIBILITY.
   234 
   235 * Probability: Introduced pinfreal as real numbers with infinity. Use pinfreal
   236 as value for measures. Introduces Lebesgue Measure based on the integral in
   237 Multivariate Analysis. Proved Radon Nikodym for arbitrary sigma finite measure
   238 spaces.
   239 
   240  INCOMPATIBILITY.
   241 
   242 * Inductive package: offers new command "inductive_simps" to automatically
   243 derive instantiated and simplified equations for inductive predicates,
   244 similar to inductive_cases.
   245 
   246 * "bij f" is now an abbreviation of "bij_betw f UNIV UNIV". surj_on is a
   247 generalization of surj, and "surj f" is now a abbreviation of "surj_on f UNIV".
   248 The theorems bij_def and surj_def are unchanged.
   249 
   250 * Function package: .psimps rules are no longer implicitly declared [simp].
   251 INCOMPATIBILITY.
   252 
   253 * Weaker versions of the "meson" and "metis" proof methods are now available in
   254   "HOL-Plain", without dependency on "Hilbert_Choice". The proof methods become
   255   more powerful after "Hilbert_Choice" is loaded in "HOL-Main".
   256 
   257 * MESON: Renamed lemmas:
   258   meson_not_conjD ~> Meson.not_conjD
   259   meson_not_disjD ~> Meson.not_disjD
   260   meson_not_notD ~> Meson.not_notD
   261   meson_not_allD ~> Meson.not_allD
   262   meson_not_exD ~> Meson.not_exD
   263   meson_imp_to_disjD ~> Meson.imp_to_disjD
   264   meson_not_impD ~> Meson.not_impD
   265   meson_iff_to_disjD ~> Meson.iff_to_disjD
   266   meson_not_iffD ~> Meson.not_iffD
   267   meson_not_refl_disj_D ~> Meson.not_refl_disj_D
   268   meson_conj_exD1 ~> Meson.conj_exD1
   269   meson_conj_exD2 ~> Meson.conj_exD2
   270   meson_disj_exD ~> Meson.disj_exD
   271   meson_disj_exD1 ~> Meson.disj_exD1
   272   meson_disj_exD2 ~> Meson.disj_exD2
   273   meson_disj_assoc ~> Meson.disj_assoc
   274   meson_disj_comm ~> Meson.disj_comm
   275   meson_disj_FalseD1 ~> Meson.disj_FalseD1
   276   meson_disj_FalseD2 ~> Meson.disj_FalseD2
   277 INCOMPATIBILITY.
   278 
   279 * Sledgehammer: Renamed lemmas:
   280   COMBI_def ~> Meson.COMBI_def
   281   COMBK_def ~> Meson.COMBK_def
   282   COMBB_def ~> Meson.COMBB_def
   283   COMBC_def ~> Meson.COMBC_def
   284   COMBS_def ~> Meson.COMBS_def
   285   abs_I ~> Meson.abs_I
   286   abs_K ~> Meson.abs_K
   287   abs_B ~> Meson.abs_B
   288   abs_C ~> Meson.abs_C
   289   abs_S ~> Meson.abs_S
   290 INCOMPATIBILITY.
   291 
   292 
   293 *** FOL ***
   294 
   295 * All constant names are now qualified.  INCOMPATIBILITY.
   296 
   297 
   298 *** ZF ***
   299 
   300 * All constant names are now qualified.  INCOMPATIBILITY.
   301 
   302 
   303 *** ML ***
   304 
   305 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   306 meaning.
   307 
   308 * Renamed structure PureThy to Pure_Thy and moved most of its
   309 operations to structure Global_Theory, to emphasize that this is
   310 rarely-used global-only stuff.
   311 
   312 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
   313 instead (or tracing for high-volume output).
   314 
   315 * Configuration option show_question_marks only affects regular pretty
   316 printing of types and terms, not raw Term.string_of_vname.
   317 
   318 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
   319 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
   320 @{thms} for most purposes.
   321 
   322 * ML structure Unsynchronized never opened, not even in Isar
   323 interaction mode as before.  Old Unsynchronized.set etc. have been
   324 discontinued -- use plain := instead.  This should be *rare* anyway,
   325 since modern tools always work via official context data, notably
   326 configuration options.
   327 
   328 * ML antiquotations @{theory} and @{theory_ref} refer to named
   329 theories from the ancestry of the current context, not any accidental
   330 theory loader state as before.  Potential INCOMPATIBILITY, subtle
   331 change in semantics.
   332 
   333 * Parallel and asynchronous execution requires special care concerning
   334 interrupts.  Structure Exn provides some convenience functions that
   335 avoid working directly with raw Interrupt.  User code must not absorb
   336 interrupts -- intermediate handling (for cleanup etc.) needs to be
   337 followed by re-raising of the original exception.  Another common
   338 source of mistakes are "handle _" patterns, which make the meaning of
   339 the program subject to physical effects of the environment.
   340 
   341 
   342 *** System ***
   343 
   344 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   345 
   346 
   347 
   348 New in Isabelle2009-2 (June 2010)
   349 ---------------------------------
   350 
   351 *** General ***
   352 
   353 * Authentic syntax for *all* logical entities (type classes, type
   354 constructors, term constants): provides simple and robust
   355 correspondence between formal entities and concrete syntax.  Within
   356 the parse tree / AST representations, "constants" are decorated by
   357 their category (class, type, const) and spelled out explicitly with
   358 their full internal name.
   359 
   360 Substantial INCOMPATIBILITY concerning low-level syntax declarations
   361 and translations (translation rules and translation functions in ML).
   362 Some hints on upgrading:
   363 
   364   - Many existing uses of 'syntax' and 'translations' can be replaced
   365     by more modern 'type_notation', 'notation' and 'abbreviation',
   366     which are independent of this issue.
   367 
   368   - 'translations' require markup within the AST; the term syntax
   369     provides the following special forms:
   370 
   371       CONST c   -- produces syntax version of constant c from context
   372       XCONST c  -- literally c, checked as constant from context
   373       c         -- literally c, if declared by 'syntax'
   374 
   375     Plain identifiers are treated as AST variables -- occasionally the
   376     system indicates accidental variables via the error "rhs contains
   377     extra variables".
   378 
   379     Type classes and type constructors are marked according to their
   380     concrete syntax.  Some old translations rules need to be written
   381     for the "type" category, using type constructor application
   382     instead of pseudo-term application of the default category
   383     "logic".
   384 
   385   - 'parse_translation' etc. in ML may use the following
   386     antiquotations:
   387 
   388       @{class_syntax c}   -- type class c within parse tree / AST
   389       @{term_syntax c}    -- type constructor c within parse tree / AST
   390       @{const_syntax c}   -- ML version of "CONST c" above
   391       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
   392 
   393   - Literal types within 'typed_print_translations', i.e. those *not*
   394     represented as pseudo-terms are represented verbatim.  Use @{class
   395     c} or @{type_name c} here instead of the above syntax
   396     antiquotations.
   397 
   398 Note that old non-authentic syntax was based on unqualified base
   399 names, so all of the above "constant" names would coincide.  Recall
   400 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
   401 diagnose syntax problems.
   402 
   403 * Type constructors admit general mixfix syntax, not just infix.
   404 
   405 * Concrete syntax may be attached to local entities without a proof
   406 body, too.  This works via regular mixfix annotations for 'fix',
   407 'def', 'obtain' etc. or via the explicit 'write' command, which is
   408 similar to the 'notation' command in theory specifications.
   409 
   410 * Discontinued unnamed infix syntax (legacy feature for many years) --
   411 need to specify constant name and syntax separately.  Internal ML
   412 datatype constructors have been renamed from InfixName to Infix etc.
   413 Minor INCOMPATIBILITY.
   414 
   415 * Schematic theorem statements need to be explicitly markup as such,
   416 via commands 'schematic_lemma', 'schematic_theorem',
   417 'schematic_corollary'.  Thus the relevance of the proof is made
   418 syntactically clear, which impacts performance in a parallel or
   419 asynchronous interactive environment.  Minor INCOMPATIBILITY.
   420 
   421 * Use of cumulative prems via "!" in some proof methods has been
   422 discontinued (old legacy feature).
   423 
   424 * References 'trace_simp' and 'debug_simp' have been replaced by
   425 configuration options stored in the context. Enabling tracing (the
   426 case of debugging is similar) in proofs works via
   427 
   428   using [[trace_simp = true]]
   429 
   430 Tracing is then active for all invocations of the simplifier in
   431 subsequent goal refinement steps. Tracing may also still be enabled or
   432 disabled via the ProofGeneral settings menu.
   433 
   434 * Separate commands 'hide_class', 'hide_type', 'hide_const',
   435 'hide_fact' replace the former 'hide' KIND command.  Minor
   436 INCOMPATIBILITY.
   437 
   438 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
   439 more efficient than combinations with -q1 or -q2.
   440 
   441 
   442 *** Pure ***
   443 
   444 * Proofterms record type-class reasoning explicitly, using the
   445 "unconstrain" operation internally.  This eliminates all sort
   446 constraints from a theorem and proof, introducing explicit
   447 OFCLASS-premises.  On the proof term level, this operation is
   448 automatically applied at theorem boundaries, such that closed proofs
   449 are always free of sort constraints.  INCOMPATIBILITY for tools that
   450 inspect proof terms.
   451 
   452 * Local theory specifications may depend on extra type variables that
   453 are not present in the result type -- arguments TYPE('a) :: 'a itself
   454 are added internally.  For example:
   455 
   456   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
   457 
   458 * Predicates of locales introduced by classes carry a mandatory
   459 "class" prefix.  INCOMPATIBILITY.
   460 
   461 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
   462 
   463 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
   464 'class' instead.
   465 
   466 * Command 'code_reflect' allows to incorporate generated ML code into
   467 runtime environment; replaces immature code_datatype antiquotation.
   468 INCOMPATIBILITY.
   469 
   470 * Code generator: simple concept for abstract datatypes obeying
   471 invariants.
   472 
   473 * Code generator: details of internal data cache have no impact on the
   474 user space functionality any longer.
   475 
   476 * Methods "unfold_locales" and "intro_locales" ignore non-locale
   477 subgoals.  This is more appropriate for interpretations with 'where'.
   478 INCOMPATIBILITY.
   479 
   480 * Command 'example_proof' opens an empty proof body.  This allows to
   481 experiment with Isar, without producing any persistent result.
   482 
   483 * Commands 'type_notation' and 'no_type_notation' declare type syntax
   484 within a local theory context, with explicit checking of the
   485 constructors involved (in contrast to the raw 'syntax' versions).
   486 
   487 * Commands 'types' and 'typedecl' now work within a local theory
   488 context -- without introducing dependencies on parameters or
   489 assumptions, which is not possible in Isabelle/Pure.
   490 
   491 * Command 'defaultsort' has been renamed to 'default_sort', it works
   492 within a local theory context.  Minor INCOMPATIBILITY.
   493 
   494 
   495 *** HOL ***
   496 
   497 * Command 'typedef' now works within a local theory context -- without
   498 introducing dependencies on parameters or assumptions, which is not
   499 possible in Isabelle/Pure/HOL.  Note that the logical environment may
   500 contain multiple interpretations of local typedefs (with different
   501 non-emptiness proofs), even in a global theory context.
   502 
   503 * New package for quotient types.  Commands 'quotient_type' and
   504 'quotient_definition' may be used for defining types and constants by
   505 quotient constructions.  An example is the type of integers created by
   506 quotienting pairs of natural numbers:
   507 
   508   fun
   509     intrel :: "(nat * nat) => (nat * nat) => bool"
   510   where
   511     "intrel (x, y) (u, v) = (x + v = u + y)"
   512 
   513   quotient_type int = "nat * nat" / intrel
   514     by (auto simp add: equivp_def expand_fun_eq)
   515 
   516   quotient_definition
   517     "0::int" is "(0::nat, 0::nat)"
   518 
   519 The method "lifting" can be used to lift of theorems from the
   520 underlying "raw" type to the quotient type.  The example
   521 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
   522 construction and provides a reasoning infrastructure for finite sets.
   523 
   524 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
   525 clash with new theory Quotient in Main HOL.
   526 
   527 * Moved the SMT binding into the main HOL session, eliminating
   528 separate HOL-SMT session.
   529 
   530 * List membership infix mem operation is only an input abbreviation.
   531 INCOMPATIBILITY.
   532 
   533 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
   534 for future developements; former Library/Word.thy is still present in
   535 the AFP entry RSAPPS.
   536 
   537 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
   538 longer shadowed.  INCOMPATIBILITY.
   539 
   540 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
   541 INCOMPATIBILITY.
   542 
   543 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
   544 INCOMPATIBILITY.
   545 
   546 * Dropped normalizing_semiring etc; use the facts in semiring classes
   547 instead.  INCOMPATIBILITY.
   548 
   549 * Dropped several real-specific versions of lemmas about floor and
   550 ceiling; use the generic lemmas from theory "Archimedean_Field"
   551 instead.  INCOMPATIBILITY.
   552 
   553   floor_number_of_eq         ~> floor_number_of
   554   le_floor_eq_number_of      ~> number_of_le_floor
   555   le_floor_eq_zero           ~> zero_le_floor
   556   le_floor_eq_one            ~> one_le_floor
   557   floor_less_eq_number_of    ~> floor_less_number_of
   558   floor_less_eq_zero         ~> floor_less_zero
   559   floor_less_eq_one          ~> floor_less_one
   560   less_floor_eq_number_of    ~> number_of_less_floor
   561   less_floor_eq_zero         ~> zero_less_floor
   562   less_floor_eq_one          ~> one_less_floor
   563   floor_le_eq_number_of      ~> floor_le_number_of
   564   floor_le_eq_zero           ~> floor_le_zero
   565   floor_le_eq_one            ~> floor_le_one
   566   floor_subtract_number_of   ~> floor_diff_number_of
   567   floor_subtract_one         ~> floor_diff_one
   568   ceiling_number_of_eq       ~> ceiling_number_of
   569   ceiling_le_eq_number_of    ~> ceiling_le_number_of
   570   ceiling_le_zero_eq         ~> ceiling_le_zero
   571   ceiling_le_eq_one          ~> ceiling_le_one
   572   less_ceiling_eq_number_of  ~> number_of_less_ceiling
   573   less_ceiling_eq_zero       ~> zero_less_ceiling
   574   less_ceiling_eq_one        ~> one_less_ceiling
   575   ceiling_less_eq_number_of  ~> ceiling_less_number_of
   576   ceiling_less_eq_zero       ~> ceiling_less_zero
   577   ceiling_less_eq_one        ~> ceiling_less_one
   578   le_ceiling_eq_number_of    ~> number_of_le_ceiling
   579   le_ceiling_eq_zero         ~> zero_le_ceiling
   580   le_ceiling_eq_one          ~> one_le_ceiling
   581   ceiling_subtract_number_of ~> ceiling_diff_number_of
   582   ceiling_subtract_one       ~> ceiling_diff_one
   583 
   584 * Theory "Finite_Set": various folding_XXX locales facilitate the
   585 application of the various fold combinators on finite sets.
   586 
   587 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
   588 provides abstract red-black tree type which is backed by "RBT_Impl" as
   589 implementation.  INCOMPATIBILTY.
   590 
   591 * Theory Library/Coinductive_List has been removed -- superseded by
   592 AFP/thys/Coinductive.
   593 
   594 * Theory PReal, including the type "preal" and related operations, has
   595 been removed.  INCOMPATIBILITY.
   596 
   597 * Real: new development using Cauchy Sequences.
   598 
   599 * Split off theory "Big_Operators" containing setsum, setprod,
   600 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
   601 
   602 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
   603 "Int" etc.  INCOMPATIBILITY.
   604 
   605 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
   606 
   607 * New set of rules "ac_simps" provides combined assoc / commute
   608 rewrites for all interpretations of the appropriate generic locales.
   609 
   610 * Renamed theory "OrderedGroup" to "Groups" and split theory
   611 "Ring_and_Field" into theories "Rings" and "Fields"; for more
   612 appropriate and more consistent names suitable for name prefixes
   613 within the HOL theories.  INCOMPATIBILITY.
   614 
   615 * Some generic constants have been put to appropriate theories:
   616   - less_eq, less: Orderings
   617   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
   618   - inverse, divide: Rings
   619 INCOMPATIBILITY.
   620 
   621 * More consistent naming of type classes involving orderings (and
   622 lattices):
   623 
   624     lower_semilattice                   ~> semilattice_inf
   625     upper_semilattice                   ~> semilattice_sup
   626 
   627     dense_linear_order                  ~> dense_linorder
   628 
   629     pordered_ab_group_add               ~> ordered_ab_group_add
   630     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
   631     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
   632     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
   633     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
   634     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
   635     pordered_cancel_semiring            ~> ordered_cancel_semiring
   636     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
   637     pordered_comm_ring                  ~> ordered_comm_ring
   638     pordered_comm_semiring              ~> ordered_comm_semiring
   639     pordered_ring                       ~> ordered_ring
   640     pordered_ring_abs                   ~> ordered_ring_abs
   641     pordered_semiring                   ~> ordered_semiring
   642 
   643     ordered_ab_group_add                ~> linordered_ab_group_add
   644     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
   645     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
   646     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
   647     ordered_field                       ~> linordered_field
   648     ordered_field_no_lb                 ~> linordered_field_no_lb
   649     ordered_field_no_ub                 ~> linordered_field_no_ub
   650     ordered_field_dense_linear_order    ~> dense_linordered_field
   651     ordered_idom                        ~> linordered_idom
   652     ordered_ring                        ~> linordered_ring
   653     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
   654     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
   655     ordered_ring_strict                 ~> linordered_ring_strict
   656     ordered_semidom                     ~> linordered_semidom
   657     ordered_semiring                    ~> linordered_semiring
   658     ordered_semiring_1                  ~> linordered_semiring_1
   659     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
   660     ordered_semiring_strict             ~> linordered_semiring_strict
   661 
   662   The following slightly odd type classes have been moved to a
   663   separate theory Library/Lattice_Algebras:
   664 
   665     lordered_ab_group_add               ~> lattice_ab_group_add
   666     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
   667     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
   668     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
   669     lordered_ring                       ~> lattice_ring
   670 
   671 INCOMPATIBILITY.
   672 
   673 * Refined field classes:
   674   - classes division_ring_inverse_zero, field_inverse_zero,
   675     linordered_field_inverse_zero include rule inverse 0 = 0 --
   676     subsumes former division_by_zero class;
   677   - numerous lemmas have been ported from field to division_ring.
   678 INCOMPATIBILITY.
   679 
   680 * Refined algebra theorem collections:
   681   - dropped theorem group group_simps, use algebra_simps instead;
   682   - dropped theorem group ring_simps, use field_simps instead;
   683   - proper theorem collection field_simps subsumes former theorem
   684     groups field_eq_simps and field_simps;
   685   - dropped lemma eq_minus_self_iff which is a duplicate for
   686     equal_neg_zero.
   687 INCOMPATIBILITY.
   688 
   689 * Theory Finite_Set and List: some lemmas have been generalized from
   690 sets to lattices:
   691 
   692   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
   693   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
   694   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
   695   union_Union_fold_union        ~> sup_Sup_fold_sup
   696   Inter_fold_inter              ~> Inf_fold_inf
   697   Union_fold_union              ~> Sup_fold_sup
   698   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
   699   union_UNION_fold_union        ~> sup_SUPR_fold_sup
   700   INTER_fold_inter              ~> INFI_fold_inf
   701   UNION_fold_union              ~> SUPR_fold_sup
   702 
   703 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
   704 replaced by the more convenient lemmas Inf_empty and Sup_empty.
   705 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
   706 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
   707 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
   708 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
   709 
   710 * Reorganized theory Multiset: swapped notation of pointwise and
   711 multiset order:
   712 
   713   - pointwise ordering is instance of class order with standard syntax
   714     <= and <;
   715   - multiset ordering has syntax <=# and <#; partial order properties
   716     are provided by means of interpretation with prefix
   717     multiset_order;
   718   - less duplication, less historical organization of sections,
   719     conversion from associations lists to multisets, rudimentary code
   720     generation;
   721   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
   722     if needed.
   723 
   724 Renamed:
   725 
   726   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
   727   multi_count_ext  ~>  multiset_ext
   728   diff_union_inverse2  ~>  diff_union_cancelR
   729 
   730 INCOMPATIBILITY.
   731 
   732 * Theory Permutation: replaced local "remove" by List.remove1.
   733 
   734 * Code generation: ML and OCaml code is decorated with signatures.
   735 
   736 * Theory List: added transpose.
   737 
   738 * Library/Nat_Bijection.thy is a collection of bijective functions
   739 between nat and other types, which supersedes the older libraries
   740 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
   741 
   742   Constants:
   743   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
   744   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
   745   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
   746   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
   747   Countable.pair_encode           ~> prod_encode
   748   NatIso.prod2nat                 ~> prod_encode
   749   NatIso.nat2prod                 ~> prod_decode
   750   NatIso.sum2nat                  ~> sum_encode
   751   NatIso.nat2sum                  ~> sum_decode
   752   NatIso.list2nat                 ~> list_encode
   753   NatIso.nat2list                 ~> list_decode
   754   NatIso.set2nat                  ~> set_encode
   755   NatIso.nat2set                  ~> set_decode
   756 
   757   Lemmas:
   758   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
   759   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
   760   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
   761   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
   762   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
   763   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
   764   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
   765   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
   766   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
   767   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
   768   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
   769   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
   770   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
   771 
   772 * Sledgehammer:
   773   - Renamed ATP commands:
   774     atp_info     ~> sledgehammer running_atps
   775     atp_kill     ~> sledgehammer kill_atps
   776     atp_messages ~> sledgehammer messages
   777     atp_minimize ~> sledgehammer minimize
   778     print_atps   ~> sledgehammer available_atps
   779     INCOMPATIBILITY.
   780   - Added user's manual ("isabelle doc sledgehammer").
   781   - Added option syntax and "sledgehammer_params" to customize
   782     Sledgehammer's behavior.  See the manual for details.
   783   - Modified the Isar proof reconstruction code so that it produces
   784     direct proofs rather than proofs by contradiction.  (This feature
   785     is still experimental.)
   786   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
   787     full-typed mode.
   788   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
   789 
   790 * Nitpick:
   791   - Added and implemented "binary_ints" and "bits" options.
   792   - Added "std" option and implemented support for nonstandard models.
   793   - Added and implemented "finitize" option to improve the precision
   794     of infinite datatypes based on a monotonicity analysis.
   795   - Added support for quotient types.
   796   - Added support for "specification" and "ax_specification"
   797     constructs.
   798   - Added support for local definitions (for "function" and
   799     "termination" proofs).
   800   - Added support for term postprocessors.
   801   - Optimized "Multiset.multiset" and "FinFun.finfun".
   802   - Improved efficiency of "destroy_constrs" optimization.
   803   - Fixed soundness bugs related to "destroy_constrs" optimization and
   804     record getters.
   805   - Fixed soundness bug related to higher-order constructors.
   806   - Fixed soundness bug when "full_descrs" is enabled.
   807   - Improved precision of set constructs.
   808   - Added "atoms" option.
   809   - Added cache to speed up repeated Kodkod invocations on the same
   810     problems.
   811   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
   812     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
   813     "SAT4J_Light".  INCOMPATIBILITY.
   814   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
   815     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
   816   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
   817 
   818 * Method "induct" now takes instantiations of the form t, where t is not
   819   a variable, as a shorthand for "x == t", where x is a fresh variable.
   820   If this is not intended, t has to be enclosed in parentheses.
   821   By default, the equalities generated by definitional instantiations
   822   are pre-simplified, which may cause parameters of inductive cases
   823   to disappear, or may even delete some of the inductive cases.
   824   Use "induct (no_simp)" instead of "induct" to restore the old
   825   behaviour. The (no_simp) option is also understood by the "cases"
   826   and "nominal_induct" methods, which now perform pre-simplification, too.
   827   INCOMPATIBILITY.
   828 
   829 
   830 *** HOLCF ***
   831 
   832 * Variable names in lemmas generated by the domain package have
   833 changed; the naming scheme is now consistent with the HOL datatype
   834 package.  Some proof scripts may be affected, INCOMPATIBILITY.
   835 
   836 * The domain package no longer defines the function "foo_copy" for
   837 recursive domain "foo".  The reach lemma is now stated directly in
   838 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
   839 be reformulated in terms of "foo_take", INCOMPATIBILITY.
   840 
   841 * Most definedness lemmas generated by the domain package (previously
   842 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
   843 like "foo$x = UU <-> x = UU", which works better as a simp rule.
   844 Proofs that used definedness lemmas as intro rules may break,
   845 potential INCOMPATIBILITY.
   846 
   847 * Induction and casedist rules generated by the domain package now
   848 declare proper case_names (one called "bottom", and one named for each
   849 constructor).  INCOMPATIBILITY.
   850 
   851 * For mutually-recursive domains, separate "reach" and "take_lemma"
   852 rules are generated for each domain, INCOMPATIBILITY.
   853 
   854   foo_bar.reach       ~> foo.reach  bar.reach
   855   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
   856 
   857 * Some lemmas generated by the domain package have been renamed for
   858 consistency with the datatype package, INCOMPATIBILITY.
   859 
   860   foo.ind        ~> foo.induct
   861   foo.finite_ind ~> foo.finite_induct
   862   foo.coind      ~> foo.coinduct
   863   foo.casedist   ~> foo.exhaust
   864   foo.exhaust    ~> foo.nchotomy
   865 
   866 * For consistency with other definition packages, the fixrec package
   867 now generates qualified theorem names, INCOMPATIBILITY.
   868 
   869   foo_simps  ~> foo.simps
   870   foo_unfold ~> foo.unfold
   871   foo_induct ~> foo.induct
   872 
   873 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
   874 method and internal fixrec proofs now use the default simpset instead.
   875 INCOMPATIBILITY.
   876 
   877 * The "contlub" predicate has been removed.  Proof scripts should use
   878 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
   879 
   880 * The "admw" predicate has been removed, INCOMPATIBILITY.
   881 
   882 * The constants cpair, cfst, and csnd have been removed in favor of
   883 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
   884 
   885 
   886 *** ML ***
   887 
   888 * Antiquotations for basic formal entities:
   889 
   890     @{class NAME}         -- type class
   891     @{class_syntax NAME}  -- syntax representation of the above
   892 
   893     @{type_name NAME}     -- logical type
   894     @{type_abbrev NAME}   -- type abbreviation
   895     @{nonterminal NAME}   -- type of concrete syntactic category
   896     @{type_syntax NAME}   -- syntax representation of any of the above
   897 
   898     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
   899     @{const_abbrev NAME}  -- abbreviated constant
   900     @{const_syntax NAME}  -- syntax representation of any of the above
   901 
   902 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
   903 syntax constant (cf. 'syntax' command).
   904 
   905 * Antiquotation @{make_string} inlines a function to print arbitrary
   906 values similar to the ML toplevel.  The result is compiler dependent
   907 and may fall back on "?" in certain situations.
   908 
   909 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
   910 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
   911 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
   912 not work with the asynchronous Isar document model.
   913 
   914 * Configuration options now admit dynamic default values, depending on
   915 the context or even global references.
   916 
   917 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
   918 uses an efficient external library if available (for Poly/ML).
   919 
   920 * Renamed some important ML structures, while keeping the old names
   921 for some time as aliases within the structure Legacy:
   922 
   923   OuterKeyword  ~>  Keyword
   924   OuterLex      ~>  Token
   925   OuterParse    ~>  Parse
   926   OuterSyntax   ~>  Outer_Syntax
   927   PrintMode     ~>  Print_Mode
   928   SpecParse     ~>  Parse_Spec
   929   ThyInfo       ~>  Thy_Info
   930   ThyLoad       ~>  Thy_Load
   931   ThyOutput     ~>  Thy_Output
   932   TypeInfer     ~>  Type_Infer
   933 
   934 Note that "open Legacy" simplifies porting of sources, but forgetting
   935 to remove it again will complicate porting again in the future.
   936 
   937 * Most operations that refer to a global context are named
   938 accordingly, e.g. Simplifier.global_context or
   939 ProofContext.init_global.  There are some situations where a global
   940 context actually works, but under normal circumstances one needs to
   941 pass the proper local context through the code!
   942 
   943 * Discontinued old TheoryDataFun with its copy/init operation -- data
   944 needs to be pure.  Functor Theory_Data_PP retains the traditional
   945 Pretty.pp argument to merge, which is absent in the standard
   946 Theory_Data version.
   947 
   948 * Sorts.certify_sort and derived "cert" operations for types and terms
   949 no longer minimize sorts.  Thus certification at the boundary of the
   950 inference kernel becomes invariant under addition of class relations,
   951 which is an important monotonicity principle.  Sorts are now minimized
   952 in the syntax layer only, at the boundary between the end-user and the
   953 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
   954 explicitly in rare situations.
   955 
   956 * Renamed old-style Drule.standard to Drule.export_without_context, to
   957 emphasize that this is in no way a standard operation.
   958 INCOMPATIBILITY.
   959 
   960 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
   961 usual for resolution.  Rare INCOMPATIBILITY.
   962 
   963 * Renamed varify/unvarify operations to varify_global/unvarify_global
   964 to emphasize that these only work in a global situation (which is
   965 quite rare).
   966 
   967 * Curried take and drop in library.ML; negative length is interpreted
   968 as infinity (as in chop).  Subtle INCOMPATIBILITY.
   969 
   970 * Proof terms: type substitutions on proof constants now use canonical
   971 order of type variables.  INCOMPATIBILITY for tools working with proof
   972 terms.
   973 
   974 * Raw axioms/defs may no longer carry sort constraints, and raw defs
   975 may no longer carry premises.  User-level specifications are
   976 transformed accordingly by Thm.add_axiom/add_def.
   977 
   978 
   979 *** System ***
   980 
   981 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
   982 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
   983 proof terms are enabled unconditionally in the new HOL-Proofs image.
   984 
   985 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
   986 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
   987 respectively.
   988 
   989 * Old lib/scripts/polyml-platform is superseded by the
   990 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
   991 variant, even on a 64 bit machine.  The following example setting
   992 prefers 64 bit if available:
   993 
   994   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
   995 
   996 * The preliminary Isabelle/jEdit application demonstrates the emerging
   997 Isabelle/Scala layer for advanced prover interaction and integration.
   998 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
   999 component.
  1000 
  1001 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1002 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1003 similar to the default assignment of the document preparation system
  1004 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1005 provides some operations for direct access to the font without asking
  1006 the user for manual installation.
  1007 
  1008 
  1009 
  1010 New in Isabelle2009-1 (December 2009)
  1011 -------------------------------------
  1012 
  1013 *** General ***
  1014 
  1015 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1016 one backslash should be used, even in ML sources.
  1017 
  1018 
  1019 *** Pure ***
  1020 
  1021 * Locale interpretation propagates mixins along the locale hierarchy.
  1022 The currently only available mixins are the equations used to map
  1023 local definitions to terms of the target domain of an interpretation.
  1024 
  1025 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1026 loc" to print all interpretations of locale "loc" in the theory.
  1027 Interpretations in proofs are not shown.
  1028 
  1029 * Thoroughly revised locales tutorial.  New section on conditional
  1030 interpretation.
  1031 
  1032 * On instantiation of classes, remaining undefined class parameters
  1033 are formally declared.  INCOMPATIBILITY.
  1034 
  1035 
  1036 *** Document preparation ***
  1037 
  1038 * New generalized style concept for printing terms: @{foo (style) ...}
  1039 instead of @{foo_style style ...}  (old form is still retained for
  1040 backward compatibility).  Styles can be also applied for
  1041 antiquotations prop, term_type and typeof.
  1042 
  1043 
  1044 *** HOL ***
  1045 
  1046 * New proof method "smt" for a combination of first-order logic with
  1047 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1048 fixed-size bitvectors; there is also basic support for higher-order
  1049 features (esp. lambda abstractions).  It is an incomplete decision
  1050 procedure based on external SMT solvers using the oracle mechanism;
  1051 for the SMT solver Z3, this method is proof-producing.  Certificates
  1052 are provided to avoid calling the external solvers solely for
  1053 re-checking proofs.  Due to a remote SMT service there is no need for
  1054 installing SMT solvers locally.  See src/HOL/SMT.
  1055 
  1056 * New commands to load and prove verification conditions generated by
  1057 the Boogie program verifier or derived systems (e.g. the Verifying C
  1058 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1059 
  1060 * New counterexample generator tool 'nitpick' based on the Kodkod
  1061 relational model finder.  See src/HOL/Tools/Nitpick and
  1062 src/HOL/Nitpick_Examples.
  1063 
  1064 * New commands 'code_pred' and 'values' to invoke the predicate
  1065 compiler and to enumerate values of inductive predicates.
  1066 
  1067 * A tabled implementation of the reflexive transitive closure.
  1068 
  1069 * New implementation of quickcheck uses generic code generator;
  1070 default generators are provided for all suitable HOL types, records
  1071 and datatypes.  Old quickcheck can be re-activated importing theory
  1072 Library/SML_Quickcheck.
  1073 
  1074 * New testing tool Mirabelle for automated proof tools.  Applies
  1075 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1076 every proof step in a theory.  To be used in batch mode via the
  1077 "mirabelle" utility.
  1078 
  1079 * New proof method "sos" (sum of squares) for nonlinear real
  1080 arithmetic (originally due to John Harison). It requires theory
  1081 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1082 works well in practice on quantifier-free real arithmetic with +, -,
  1083 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1084 inequalities between polynomials.  It makes use of external
  1085 semidefinite programming solvers.  Method "sos" generates a
  1086 certificate that can be pasted into the proof thus avoiding the need
  1087 to call an external tool every time the proof is checked.  See
  1088 src/HOL/Library/Sum_Of_Squares.
  1089 
  1090 * New method "linarith" invokes existing linear arithmetic decision
  1091 procedure only.
  1092 
  1093 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1094 
  1095 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1096 Causes full type information to be output to the ATPs.  This slows
  1097 ATPs down considerably but eliminates a source of unsound "proofs"
  1098 that fail later.
  1099 
  1100 * New method "metisFT": A version of metis that uses full type
  1101 information in order to avoid failures of proof reconstruction.
  1102 
  1103 * New evaluator "approximate" approximates an real valued term using
  1104 the same method as the approximation method.
  1105 
  1106 * Method "approximate" now supports arithmetic expressions as
  1107 boundaries of intervals and implements interval splitting and Taylor
  1108 series expansion.
  1109 
  1110 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1111 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1112 
  1113 * New theory SupInf of the supremum and infimum operators for sets of
  1114 reals.
  1115 
  1116 * New theory Probability, which contains a development of measure
  1117 theory, eventually leading to Lebesgue integration and probability.
  1118 
  1119 * Extended Multivariate Analysis to include derivation and Brouwer's
  1120 fixpoint theorem.
  1121 
  1122 * Reorganization of number theory, INCOMPATIBILITY:
  1123   - new number theory development for nat and int, in theories Divides
  1124     and GCD as well as in new session Number_Theory
  1125   - some constants and facts now suffixed with _nat and _int
  1126     accordingly
  1127   - former session NumberTheory now named Old_Number_Theory, including
  1128     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1129   - moved theory Pocklington from src/HOL/Library to
  1130     src/HOL/Old_Number_Theory
  1131 
  1132 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1133 lcm of finite and infinite sets. It is shown that they form a complete
  1134 lattice.
  1135 
  1136 * Class semiring_div requires superclass no_zero_divisors and proof of
  1137 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1138 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1139 generalized to class semiring_div, subsuming former theorems
  1140 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1141 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1142 INCOMPATIBILITY.
  1143 
  1144 * Refinements to lattice classes and sets:
  1145   - less default intro/elim rules in locale variant, more default
  1146     intro/elim rules in class variant: more uniformity
  1147   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1148     le_inf_iff
  1149   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1150     sup_aci)
  1151   - renamed ACI to inf_sup_aci
  1152   - new class "boolean_algebra"
  1153   - class "complete_lattice" moved to separate theory
  1154     "Complete_Lattice"; corresponding constants (and abbreviations)
  1155     renamed and with authentic syntax:
  1156     Set.Inf ~>    Complete_Lattice.Inf
  1157     Set.Sup ~>    Complete_Lattice.Sup
  1158     Set.INFI ~>   Complete_Lattice.INFI
  1159     Set.SUPR ~>   Complete_Lattice.SUPR
  1160     Set.Inter ~>  Complete_Lattice.Inter
  1161     Set.Union ~>  Complete_Lattice.Union
  1162     Set.INTER ~>  Complete_Lattice.INTER
  1163     Set.UNION ~>  Complete_Lattice.UNION
  1164   - authentic syntax for
  1165     Set.Pow
  1166     Set.image
  1167   - mere abbreviations:
  1168     Set.empty               (for bot)
  1169     Set.UNIV                (for top)
  1170     Set.inter               (for inf, formerly Set.Int)
  1171     Set.union               (for sup, formerly Set.Un)
  1172     Complete_Lattice.Inter  (for Inf)
  1173     Complete_Lattice.Union  (for Sup)
  1174     Complete_Lattice.INTER  (for INFI)
  1175     Complete_Lattice.UNION  (for SUPR)
  1176   - object-logic definitions as far as appropriate
  1177 
  1178 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1179 Un_subset_iff are explicitly deleted as default simp rules; then also
  1180 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1181 deleted to achieve the desired effect.
  1182 
  1183 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1184 rules by default any longer; the same applies to min_max.inf_absorb1
  1185 etc.  INCOMPATIBILITY.
  1186 
  1187 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1188 pred_set_conv by default.  INCOMPATIBILITY.
  1189 
  1190 * Power operations on relations and functions are now one dedicated
  1191 constant "compow" with infix syntax "^^".  Power operation on
  1192 multiplicative monoids retains syntax "^" and is now defined generic
  1193 in class power.  INCOMPATIBILITY.
  1194 
  1195 * Relation composition "R O S" now has a more standard argument order:
  1196 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1197 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1198 break, since the O_assoc rule was not rewritten like this.  Fix using
  1199 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1200 
  1201 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1202 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1203 INCOMPATIBILITY.
  1204 
  1205 * Most rules produced by inductive and datatype package have mandatory
  1206 prefixes.  INCOMPATIBILITY.
  1207 
  1208 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1209 the attribute of the same name.  Each of the theorems in the list
  1210 DERIV_intros assumes composition with an additional function and
  1211 matches a variable to the derivative, which has to be solved by the
  1212 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1213 of most elementary terms.  Former Maclauren.DERIV_tac and
  1214 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1215 INCOMPATIBILITY.
  1216 
  1217 * Code generator attributes follow the usual underscore convention:
  1218     code_unfold     replaces    code unfold
  1219     code_post       replaces    code post
  1220     etc.
  1221   INCOMPATIBILITY.
  1222 
  1223 * Renamed methods:
  1224     sizechange -> size_change
  1225     induct_scheme -> induction_schema
  1226   INCOMPATIBILITY.
  1227 
  1228 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1229 INCOMPATIBILITY, use "undefined" directly.
  1230 
  1231 * Renamed theorems:
  1232     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1233     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1234     Suc_plus1 -> Suc_eq_plus1
  1235     *anti_sym -> *antisym*
  1236     vector_less_eq_def -> vector_le_def
  1237   INCOMPATIBILITY.
  1238 
  1239 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1240 INCOMPATIBILITY.
  1241 
  1242 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1243 INCOMPATIBILITY.
  1244 
  1245 
  1246 *** HOLCF ***
  1247 
  1248 * Theory Representable defines a class "rep" of domains that are
  1249 representable (via an ep-pair) in the universal domain type "udom".
  1250 Instances are provided for all type constructors defined in HOLCF.
  1251 
  1252 * The 'new_domain' command is a purely definitional version of the
  1253 domain package, for representable domains.  Syntax is identical to the
  1254 old domain package.  The 'new_domain' package also supports indirect
  1255 recursion using previously-defined type constructors.  See
  1256 src/HOLCF/ex/New_Domain.thy for examples.
  1257 
  1258 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1259 on the left-hand side of an equation, and then performs
  1260 simplification.  Rewriting is done using rules declared with the
  1261 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1262 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1263 
  1264 * The pattern-match compiler in 'fixrec' can now handle constructors
  1265 with HOL function types.  Pattern-match combinators for the Pair
  1266 constructor are pre-configured.
  1267 
  1268 * The 'fixrec' package now produces better fixed-point induction rules
  1269 for mutually-recursive definitions:  Induction rules have conclusions
  1270 of the form "P foo bar" instead of "P <foo, bar>".
  1271 
  1272 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1273 been renamed to "below".  The name "below" now replaces "less" in many
  1274 theorem names.  (Legacy theorem names using "less" are still supported
  1275 as well.)
  1276 
  1277 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1278 patterns can be used to generate strictness rules, or to make
  1279 functions more strict (much like the bang-patterns supported by the
  1280 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1281 examples.
  1282 
  1283 
  1284 *** ML ***
  1285 
  1286 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1287 errors and run-time exceptions, including detailed source positions.
  1288 
  1289 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1290 identified entries, with some additional information such as source
  1291 position, logical grouping etc.
  1292 
  1293 * Theory and context data is now introduced by the simplified and
  1294 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1295 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1296 copy operation) is still available for some time.
  1297 
  1298 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1299 provides a high-level programming interface to synchronized state
  1300 variables with atomic update.  This works via pure function
  1301 application within a critical section -- its runtime should be as
  1302 short as possible; beware of deadlocks if critical code is nested,
  1303 either directly or indirectly via other synchronized variables!
  1304 
  1305 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1306 wraps raw ML references, explicitly indicating their non-thread-safe
  1307 behaviour.  The Isar toplevel keeps this structure open, to
  1308 accommodate Proof General as well as quick and dirty interactive
  1309 experiments with references.
  1310 
  1311 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1312 parallel tactical reasoning.
  1313 
  1314 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1315 are similar to SUBPROOF, but are slightly more flexible: only the
  1316 specified parts of the subgoal are imported into the context, and the
  1317 body tactic may introduce new subgoals and schematic variables.
  1318 
  1319 * Old tactical METAHYPS, which does not observe the proof context, has
  1320 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1321 or Subgoal.FOCUS etc.
  1322 
  1323 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1324 functors have their own ML name space there is no point to mark them
  1325 separately.)  Minor INCOMPATIBILITY.
  1326 
  1327 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1328 
  1329 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1330 INCOMPATIBILITY.
  1331 
  1332 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1333 mode, which avoids critical setmp.
  1334 
  1335 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1336 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1337 Attrib/Method.setup introduced in Isabelle2009.
  1338 
  1339 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1340 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1341 last resort.  INCOMPATIBILITY.
  1342 
  1343 * Display.pretty_thm now requires a proper context (cf. former
  1344 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1345 or even Display.pretty_thm_without_context as last resort.
  1346 INCOMPATIBILITY.
  1347 
  1348 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1349 Syntax.pretty_typ/term directly, preferably with proper context
  1350 instead of global theory.
  1351 
  1352 
  1353 *** System ***
  1354 
  1355 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1356 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1357 usedir option -q.
  1358 
  1359 * Support for additional "Isabelle components" via etc/components, see
  1360 also the system manual.
  1361 
  1362 * The isabelle makeall tool now operates on all components with
  1363 IsaMakefile, not just hardwired "logics".
  1364 
  1365 * Removed "compress" option from isabelle-process and isabelle usedir;
  1366 this is always enabled.
  1367 
  1368 * Discontinued support for Poly/ML 4.x versions.
  1369 
  1370 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  1371 on a given logic image.  This requires the lighttpd webserver and is
  1372 currently supported on Linux only.
  1373 
  1374 
  1375 
  1376 New in Isabelle2009 (April 2009)
  1377 --------------------------------
  1378 
  1379 *** General ***
  1380 
  1381 * Simplified main Isabelle executables, with less surprises on
  1382 case-insensitive file-systems (such as Mac OS).
  1383 
  1384   - The main Isabelle tool wrapper is now called "isabelle" instead of
  1385     "isatool."
  1386 
  1387   - The former "isabelle" alias for "isabelle-process" has been
  1388     removed (should rarely occur to regular users).
  1389 
  1390   - The former "isabelle-interface" and its alias "Isabelle" have been
  1391     removed (interfaces are now regular Isabelle tools).
  1392 
  1393 Within scripts and make files, the Isabelle environment variables
  1394 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  1395 respectively.  (The latter are still available as legacy feature.)
  1396 
  1397 The old isabelle-interface wrapper could react in confusing ways if
  1398 the interface was uninstalled or changed otherwise.  Individual
  1399 interface tool configuration is now more explicit, see also the
  1400 Isabelle system manual.  In particular, Proof General is now available
  1401 via "isabelle emacs".
  1402 
  1403 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  1404 purge installed copies of Isabelle executables and re-run "isabelle
  1405 install -p ...", or use symlinks.
  1406 
  1407 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  1408 old ~/isabelle, which was slightly non-standard and apt to cause
  1409 surprises on case-insensitive file-systems (such as Mac OS).
  1410 
  1411 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  1412 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  1413 care is required when using older releases of Isabelle.  Note that
  1414 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  1415 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  1416 
  1417 * Proofs of fully specified statements are run in parallel on
  1418 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  1419 a regular 4-core machine, if the initial heap space is made reasonably
  1420 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  1421 
  1422 * The main reference manuals ("isar-ref", "implementation", and
  1423 "system") have been updated and extended.  Formally checked references
  1424 as hyperlinks are now available uniformly.
  1425 
  1426 
  1427 *** Pure ***
  1428 
  1429 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  1430 respects.  The most important changes are listed below.  See the
  1431 Tutorial on Locales ("locales" manual) for details.
  1432 
  1433 - In locale expressions, instantiation replaces renaming.  Parameters
  1434 must be declared in a for clause.  To aid compatibility with previous
  1435 parameter inheritance, in locale declarations, parameters that are not
  1436 'touched' (instantiation position "_" or omitted) are implicitly added
  1437 with their syntax at the beginning of the for clause.
  1438 
  1439 - Syntax from abbreviations and definitions in locales is available in
  1440 locale expressions and context elements.  The latter is particularly
  1441 useful in locale declarations.
  1442 
  1443 - More flexible mechanisms to qualify names generated by locale
  1444 expressions.  Qualifiers (prefixes) may be specified in locale
  1445 expressions, and can be marked as mandatory (syntax: "name!:") or
  1446 optional (syntax "name?:").  The default depends for plain "name:"
  1447 depends on the situation where a locale expression is used: in
  1448 commands 'locale' and 'sublocale' prefixes are optional, in
  1449 'interpretation' and 'interpret' prefixes are mandatory.  The old
  1450 implicit qualifiers derived from the parameter names of a locale are
  1451 no longer generated.
  1452 
  1453 - Command "sublocale l < e" replaces "interpretation l < e".  The
  1454 instantiation clause in "interpretation" and "interpret" (square
  1455 brackets) is no longer available.  Use locale expressions.
  1456 
  1457 - When converting proof scripts, mandatory qualifiers in
  1458 'interpretation' and 'interpret' should be retained by default, even
  1459 if this is an INCOMPATIBILITY compared to former behavior.  In the
  1460 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  1461 in locale expressions range over a single locale instance only.
  1462 
  1463 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  1464 In existing theorem specifications replace the includes element by the
  1465 respective context elements of the included locale, omitting those
  1466 that are already present in the theorem specification.  Multiple
  1467 assume elements of a locale should be replaced by a single one
  1468 involving the locale predicate.  In the proof body, declarations (most
  1469 notably theorems) may be regained by interpreting the respective
  1470 locales in the proof context as required (command "interpret").
  1471 
  1472 If using "includes" in replacement of a target solely because the
  1473 parameter types in the theorem are not as general as in the target,
  1474 consider declaring a new locale with additional type constraints on
  1475 the parameters (context element "constrains").
  1476 
  1477 - Discontinued "locale (open)".  INCOMPATIBILITY.
  1478 
  1479 - Locale interpretation commands no longer attempt to simplify goal.
  1480 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  1481 methods intro_locales and unfold_locales to clarify.
  1482 
  1483 - Locale interpretation commands no longer accept interpretation
  1484 attributes.  INCOMPATIBILITY.
  1485 
  1486 * Class declaration: so-called "base sort" must not be given in import
  1487 list any longer, but is inferred from the specification.  Particularly
  1488 in HOL, write
  1489 
  1490     class foo = ...
  1491 
  1492 instead of
  1493 
  1494     class foo = type + ...
  1495 
  1496 * Class target: global versions of theorems stemming do not carry a
  1497 parameter prefix any longer.  INCOMPATIBILITY.
  1498 
  1499 * Class 'instance' command no longer accepts attached definitions.
  1500 INCOMPATIBILITY, use proper 'instantiation' target instead.
  1501 
  1502 * Recovered hiding of consts, which was accidentally broken in
  1503 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  1504 makes c inaccessible; consider using ``hide (open) const c'' instead.
  1505 
  1506 * Slightly more coherent Pure syntax, with updated documentation in
  1507 isar-ref manual.  Removed locales meta_term_syntax and
  1508 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  1509 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  1510 directly in regular applications.
  1511 
  1512 * There is a new syntactic category "float_const" for signed decimal
  1513 fractions (e.g. 123.45 or -123.45).
  1514 
  1515 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  1516 interface with 'setup' command instead.
  1517 
  1518 * Command 'local_setup' is similar to 'setup', but operates on a local
  1519 theory context.
  1520 
  1521 * The 'axiomatization' command now only works within a global theory
  1522 context.  INCOMPATIBILITY.
  1523 
  1524 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  1525 hypotheses.  Sorts required in the course of reasoning need to be
  1526 covered by the constraints in the initial statement, completed by the
  1527 type instance information of the background theory.  Non-trivial sort
  1528 hypotheses, which rarely occur in practice, may be specified via
  1529 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  1530 
  1531   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  1532 
  1533 The result contains an implicit sort hypotheses as before --
  1534 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  1535 normalization.
  1536 
  1537 * Generalized Isar history, with support for linear undo, direct state
  1538 addressing etc.
  1539 
  1540 * Changed defaults for unify configuration options:
  1541 
  1542   unify_trace_bound = 50 (formerly 25)
  1543   unify_search_bound = 60 (formerly 30)
  1544 
  1545 * Different bookkeeping for code equations (INCOMPATIBILITY):
  1546 
  1547   a) On theory merge, the last set of code equations for a particular
  1548      constant is taken (in accordance with the policy applied by other
  1549      parts of the code generator framework).
  1550 
  1551   b) Code equations stemming from explicit declarations (e.g. code
  1552      attribute) gain priority over default code equations stemming
  1553      from definition, primrec, fun etc.
  1554 
  1555 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  1556 
  1557 * Unified theorem tables for both code generators.  Thus [code
  1558 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  1559 
  1560 * Command 'find_consts' searches for constants based on type and name
  1561 patterns, e.g.
  1562 
  1563     find_consts "_ => bool"
  1564 
  1565 By default, matching is against subtypes, but it may be restricted to
  1566 the whole type.  Searching by name is possible.  Multiple queries are
  1567 conjunctive and queries may be negated by prefixing them with a
  1568 hyphen:
  1569 
  1570     find_consts strict: "_ => bool" name: "Int" -"int => int"
  1571 
  1572 * New 'find_theorems' criterion "solves" matches theorems that
  1573 directly solve the current goal (modulo higher-order unification).
  1574 
  1575 * Auto solve feature for main theorem statements: whenever a new goal
  1576 is stated, "find_theorems solves" is called; any theorems that could
  1577 solve the lemma directly are listed as part of the goal state.
  1578 Cf. associated options in Proof General Isabelle settings menu,
  1579 enabled by default, with reasonable timeout for pathological cases of
  1580 higher-order unification.
  1581 
  1582 
  1583 *** Document preparation ***
  1584 
  1585 * Antiquotation @{lemma} now imitates a regular terminal proof,
  1586 demanding keyword 'by' and supporting the full method expression
  1587 syntax just like the Isar command 'by'.
  1588 
  1589 
  1590 *** HOL ***
  1591 
  1592 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  1593 points Main and Complex_Main remain as before.
  1594 
  1595 * Logic image HOL-Plain provides a minimal HOL with the most important
  1596 tools available (inductive, datatype, primrec, ...).  This facilitates
  1597 experimentation and tool development.  Note that user applications
  1598 (and library theories) should never refer to anything below theory
  1599 Main, as before.
  1600 
  1601 * Logic image HOL-Main stops at theory Main, and thus facilitates
  1602 experimentation due to shorter build times.
  1603 
  1604 * Logic image HOL-NSA contains theories of nonstandard analysis which
  1605 were previously part of former HOL-Complex.  Entry point Hyperreal
  1606 remains valid, but theories formerly using Complex_Main should now use
  1607 new entry point Hypercomplex.
  1608 
  1609 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  1610 Posix processes.  Avoids potentially expensive forking of the ML
  1611 process.  New thread-based implementation also works on non-Unix
  1612 platforms (Cygwin).  Provers are no longer hardwired, but defined
  1613 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  1614 commands are covered in the isar-ref manual.
  1615 
  1616 * Wrapper scripts for remote SystemOnTPTP service allows to use
  1617 sledgehammer without local ATP installation (Vampire etc.). Other
  1618 provers may be included via suitable ML wrappers, see also
  1619 src/HOL/ATP_Linkup.thy.
  1620 
  1621 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  1622 menu.
  1623 
  1624 * The metis method no longer fails because the theorem is too trivial
  1625 (contains the empty clause).
  1626 
  1627 * The metis method now fails in the usual manner, rather than raising
  1628 an exception, if it determines that it cannot prove the theorem.
  1629 
  1630 * Method "coherent" implements a prover for coherent logic (see also
  1631 src/Tools/coherent.ML).
  1632 
  1633 * Constants "undefined" and "default" replace "arbitrary".  Usually
  1634 "undefined" is the right choice to replace "arbitrary", though
  1635 logically there is no difference.  INCOMPATIBILITY.
  1636 
  1637 * Command "value" now integrates different evaluation mechanisms.  The
  1638 result of the first successful evaluation mechanism is printed.  In
  1639 square brackets a particular named evaluation mechanisms may be
  1640 specified (currently, [SML], [code] or [nbe]).  See further
  1641 src/HOL/ex/Eval_Examples.thy.
  1642 
  1643 * Normalization by evaluation now allows non-leftlinear equations.
  1644 Declare with attribute [code nbe].
  1645 
  1646 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  1647 as the structured Isar versions "cases" and "induct", cf. the
  1648 corresponding "cases" and "induct" attributes.  Mutual induction rules
  1649 are now presented as a list of individual projections
  1650 (e.g. foo_bar.inducts for types foo and bar); the old format with
  1651 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  1652 rare situations a different rule is selected --- notably nested tuple
  1653 elimination instead of former prod.exhaust: use explicit (case_tac t
  1654 rule: prod.exhaust) here.
  1655 
  1656 * Attributes "cases", "induct", "coinduct" support "del" option.
  1657 
  1658 * Removed fact "case_split_thm", which duplicates "case_split".
  1659 
  1660 * The option datatype has been moved to a new theory Option.  Renamed
  1661 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  1662 
  1663 * New predicate "strict_mono" classifies strict functions on partial
  1664 orders.  With strict functions on linear orders, reasoning about
  1665 (in)equalities is facilitated by theorems "strict_mono_eq",
  1666 "strict_mono_less_eq" and "strict_mono_less".
  1667 
  1668 * Some set operations are now proper qualified constants with
  1669 authentic syntax.  INCOMPATIBILITY:
  1670 
  1671     op Int ~>   Set.Int
  1672     op Un ~>    Set.Un
  1673     INTER ~>    Set.INTER
  1674     UNION ~>    Set.UNION
  1675     Inter ~>    Set.Inter
  1676     Union ~>    Set.Union
  1677     {} ~>       Set.empty
  1678     UNIV ~>     Set.UNIV
  1679 
  1680 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  1681 theory Set.
  1682 
  1683 * Auxiliary class "itself" has disappeared -- classes without any
  1684 parameter are treated as expected by the 'class' command.
  1685 
  1686 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  1687 
  1688 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  1689 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  1690 
  1691 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  1692 method "approximation".  It proves formulas on real values by using
  1693 interval arithmetic.  In the formulas are also the transcendental
  1694 functions sin, cos, tan, atan, ln, exp and the constant pi are
  1695 allowed. For examples see
  1696 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  1697 
  1698 * Theory "Reflection" now resides in HOL/Library.
  1699 
  1700 * Entry point to Word library now simply named "Word".
  1701 INCOMPATIBILITY.
  1702 
  1703 * Made source layout more coherent with logical distribution
  1704 structure:
  1705 
  1706     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  1707     src/HOL/Library/Code_Message.thy ~> src/HOL/
  1708     src/HOL/Library/GCD.thy ~> src/HOL/
  1709     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  1710     src/HOL/Library/Parity.thy ~> src/HOL/
  1711     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  1712     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  1713     src/HOL/Real/Lubs.thy ~> src/HOL/
  1714     src/HOL/Real/PReal.thy ~> src/HOL/
  1715     src/HOL/Real/Rational.thy ~> src/HOL/
  1716     src/HOL/Real/RComplete.thy ~> src/HOL/
  1717     src/HOL/Real/RealDef.thy ~> src/HOL/
  1718     src/HOL/Real/RealPow.thy ~> src/HOL/
  1719     src/HOL/Real/Real.thy ~> src/HOL/
  1720     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  1721     src/HOL/Complex/Complex.thy ~> src/HOL/
  1722     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  1723     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  1724     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  1725     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  1726     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  1727     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  1728     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  1729     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  1730     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  1731     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  1732     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  1733     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  1734     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  1735     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  1736     src/HOL/Real/Float ~> src/HOL/Library/
  1737     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  1738     src/HOL/Real/RealVector.thy ~> src/HOL/
  1739 
  1740     src/HOL/arith_data.ML ~> src/HOL/Tools
  1741     src/HOL/hologic.ML ~> src/HOL/Tools
  1742     src/HOL/simpdata.ML ~> src/HOL/Tools
  1743     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  1744     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  1745     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  1746     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  1747     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  1748     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  1749     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  1750 
  1751     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  1752     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  1753     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  1754     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  1755     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  1756     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  1757 
  1758 * If methods "eval" and "evaluation" encounter a structured proof
  1759 state with !!/==>, only the conclusion is evaluated to True (if
  1760 possible), avoiding strange error messages.
  1761 
  1762 * Method "sizechange" automates termination proofs using (a
  1763 modification of) the size-change principle.  Requires SAT solver.  See
  1764 src/HOL/ex/Termination.thy for examples.
  1765 
  1766 * Simplifier: simproc for let expressions now unfolds if bound
  1767 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  1768 
  1769 * Method "arith": Linear arithmetic now ignores all inequalities when
  1770 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  1771 
  1772 * New attribute "arith" for facts that should always be used
  1773 automatically by arithmetic. It is intended to be used locally in
  1774 proofs, e.g.
  1775 
  1776   assumes [arith]: "x > 0"
  1777 
  1778 Global usage is discouraged because of possible performance impact.
  1779 
  1780 * New classes "top" and "bot" with corresponding operations "top" and
  1781 "bot" in theory Orderings; instantiation of class "complete_lattice"
  1782 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  1783 
  1784 * Changed definition lemma "less_fun_def" in order to provide an
  1785 instance for preorders on functions; use lemma "less_le" instead.
  1786 INCOMPATIBILITY.
  1787 
  1788 * Theory Orderings: class "wellorder" moved here, with explicit
  1789 induction rule "less_induct" as assumption.  For instantiation of
  1790 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  1791 INCOMPATIBILITY.
  1792 
  1793 * Theory Orderings: added class "preorder" as superclass of "order".
  1794 INCOMPATIBILITY: Instantiation proofs for order, linorder
  1795 etc. slightly changed.  Some theorems named order_class.* now named
  1796 preorder_class.*.
  1797 
  1798 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  1799 "diag" to "Id_on".
  1800 
  1801 * Theory Finite_Set: added a new fold combinator of type
  1802 
  1803   ('a => 'b => 'b) => 'b => 'a set => 'b
  1804 
  1805 Occasionally this is more convenient than the old fold combinator
  1806 which is now defined in terms of the new one and renamed to
  1807 fold_image.
  1808 
  1809 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  1810 and "ring_simps" have been replaced by "algebra_simps" (which can be
  1811 extended with further lemmas!).  At the moment both still exist but
  1812 the former will disappear at some point.
  1813 
  1814 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  1815 class recpower.  Type-specific simp rules for various recpower types
  1816 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  1817 
  1818 rat_power_0    -> power_0
  1819 rat_power_Suc  -> power_Suc
  1820 realpow_0      -> power_0
  1821 realpow_Suc    -> power_Suc
  1822 complexpow_0   -> power_0
  1823 complexpow_Suc -> power_Suc
  1824 power_poly_0   -> power_0
  1825 power_poly_Suc -> power_Suc
  1826 
  1827 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  1828 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  1829 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  1830 of lemmas from Divides has been generalized from nat to class
  1831 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  1832 renames resulting from duplicate elimination:
  1833 
  1834     dvd_def_mod ~>          dvd_eq_mod_eq_0
  1835     zero_dvd_iff ~>         dvd_0_left_iff
  1836     dvd_0 ~>                dvd_0_right
  1837     DIVISION_BY_ZERO_DIV ~> div_by_0
  1838     DIVISION_BY_ZERO_MOD ~> mod_by_0
  1839     mult_div ~>             div_mult_self2_is_id
  1840     mult_mod ~>             mod_mult_self2_is_0
  1841 
  1842 * Theory IntDiv: removed many lemmas that are instances of class-based
  1843 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  1844 rename old lemmas as follows:
  1845 
  1846 dvd_diff               -> nat_dvd_diff
  1847 dvd_zminus_iff         -> dvd_minus_iff
  1848 mod_add1_eq            -> mod_add_eq
  1849 mod_mult1_eq           -> mod_mult_right_eq
  1850 mod_mult1_eq'          -> mod_mult_left_eq
  1851 mod_mult_distrib_mod   -> mod_mult_eq
  1852 nat_mod_add_left_eq    -> mod_add_left_eq
  1853 nat_mod_add_right_eq   -> mod_add_right_eq
  1854 nat_mod_div_trivial    -> mod_div_trivial
  1855 nat_mod_mod_trivial    -> mod_mod_trivial
  1856 zdiv_zadd_self1        -> div_add_self1
  1857 zdiv_zadd_self2        -> div_add_self2
  1858 zdiv_zmult_self1       -> div_mult_self2_is_id
  1859 zdiv_zmult_self2       -> div_mult_self1_is_id
  1860 zdvd_triv_left         -> dvd_triv_left
  1861 zdvd_triv_right        -> dvd_triv_right
  1862 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  1863 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  1864 zmod_zadd_left_eq      -> mod_add_left_eq
  1865 zmod_zadd_right_eq     -> mod_add_right_eq
  1866 zmod_zadd_self1        -> mod_add_self1
  1867 zmod_zadd_self2        -> mod_add_self2
  1868 zmod_zadd1_eq          -> mod_add_eq
  1869 zmod_zdiff1_eq         -> mod_diff_eq
  1870 zmod_zdvd_zmod         -> mod_mod_cancel
  1871 zmod_zmod_cancel       -> mod_mod_cancel
  1872 zmod_zmult_self1       -> mod_mult_self2_is_0
  1873 zmod_zmult_self2       -> mod_mult_self1_is_0
  1874 zmod_1                 -> mod_by_1
  1875 zdiv_1                 -> div_by_1
  1876 zdvd_abs1              -> abs_dvd_iff
  1877 zdvd_abs2              -> dvd_abs_iff
  1878 zdvd_refl              -> dvd_refl
  1879 zdvd_trans             -> dvd_trans
  1880 zdvd_zadd              -> dvd_add
  1881 zdvd_zdiff             -> dvd_diff
  1882 zdvd_zminus_iff        -> dvd_minus_iff
  1883 zdvd_zminus2_iff       -> minus_dvd_iff
  1884 zdvd_zmultD            -> dvd_mult_right
  1885 zdvd_zmultD2           -> dvd_mult_left
  1886 zdvd_zmult_mono        -> mult_dvd_mono
  1887 zdvd_0_right           -> dvd_0_right
  1888 zdvd_0_left            -> dvd_0_left_iff
  1889 zdvd_1_left            -> one_dvd
  1890 zminus_dvd_iff         -> minus_dvd_iff
  1891 
  1892 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  1893 
  1894 * The real numbers offer decimal input syntax: 12.34 is translated
  1895 into 1234/10^2. This translation is not reversed upon output.
  1896 
  1897 * Theory Library/Polynomial defines an abstract type 'a poly of
  1898 univariate polynomials with coefficients of type 'a.  In addition to
  1899 the standard ring operations, it also supports div and mod.  Code
  1900 generation is also supported, using list-style constructors.
  1901 
  1902 * Theory Library/Inner_Product defines a class of real_inner for real
  1903 inner product spaces, with an overloaded operation inner :: 'a => 'a
  1904 => real.  Class real_inner is a subclass of real_normed_vector from
  1905 theory RealVector.
  1906 
  1907 * Theory Library/Product_Vector provides instances for the product
  1908 type 'a * 'b of several classes from RealVector and Inner_Product.
  1909 Definitions of addition, subtraction, scalar multiplication, norms,
  1910 and inner products are included.
  1911 
  1912 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  1913 addition to the field operations, numerals and case syntax are also
  1914 supported.
  1915 
  1916 * Theory Library/Diagonalize provides constructive version of Cantor's
  1917 first diagonalization argument.
  1918 
  1919 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  1920 zlcm (for int); carried together from various gcd/lcm developements in
  1921 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  1922 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  1923 may recover tupled syntax as follows:
  1924 
  1925     hide (open) const gcd
  1926     abbreviation gcd where
  1927       "gcd == (%(a, b). GCD.gcd a b)"
  1928     notation (output)
  1929       GCD.gcd ("gcd '(_, _')")
  1930 
  1931 The same works for lcm, zgcd, zlcm.
  1932 
  1933 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  1934 instantiations for algebraic structures.  Removed some duplicate
  1935 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  1936 
  1937 * ML antiquotation @{code} takes a constant as argument and generates
  1938 corresponding code in background and inserts name of the corresponding
  1939 resulting ML value/function/datatype constructor binding in place.
  1940 All occurrences of @{code} with a single ML block are generated
  1941 simultaneously.  Provides a generic and safe interface for
  1942 instrumentalizing code generation.  See
  1943 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  1944 In future you ought to refrain from ad-hoc compiling generated SML
  1945 code on the ML toplevel.  Note that (for technical reasons) @{code}
  1946 cannot refer to constants for which user-defined serializations are
  1947 set.  Refer to the corresponding ML counterpart directly in that
  1948 cases.
  1949 
  1950 * Command 'rep_datatype': instead of theorem names the command now
  1951 takes a list of terms denoting the constructors of the type to be
  1952 represented as datatype.  The characteristic theorems have to be
  1953 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  1954 have disappeared in favour of existing ones:
  1955 
  1956     unit_induct                 ~> unit.induct
  1957     prod_induct                 ~> prod.induct
  1958     sum_induct                  ~> sum.induct
  1959     Suc_Suc_eq                  ~> nat.inject
  1960     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  1961 
  1962 
  1963 *** HOL-Algebra ***
  1964 
  1965 * New locales for orders and lattices where the equivalence relation
  1966 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  1967 locales use a record structure with field eq for the equivalence.
  1968 
  1969 * New theory of factorial domains.
  1970 
  1971 * Units_l_inv and Units_r_inv are now simp rules by default.
  1972 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  1973 and/or r_inv will now also require deletion of these lemmas.
  1974 
  1975 * Renamed the following theorems, INCOMPATIBILITY:
  1976 
  1977 UpperD ~> Upper_memD
  1978 LowerD ~> Lower_memD
  1979 least_carrier ~> least_closed
  1980 greatest_carrier ~> greatest_closed
  1981 greatest_Lower_above ~> greatest_Lower_below
  1982 one_zero ~> carrier_one_zero
  1983 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  1984 
  1985 
  1986 *** HOL-Nominal ***
  1987 
  1988 * Nominal datatypes can now contain type-variables.
  1989 
  1990 * Commands 'nominal_inductive' and 'equivariance' work with local
  1991 theory targets.
  1992 
  1993 * Nominal primrec can now works with local theory targets and its
  1994 specification syntax now conforms to the general format as seen in
  1995 'inductive' etc.
  1996 
  1997 * Method "perm_simp" honours the standard simplifier attributes
  1998 (no_asm), (no_asm_use) etc.
  1999 
  2000 * The new predicate #* is defined like freshness, except that on the
  2001 left hand side can be a set or list of atoms.
  2002 
  2003 * Experimental command 'nominal_inductive2' derives strong induction
  2004 principles for inductive definitions.  In contrast to
  2005 'nominal_inductive', which can only deal with a fixed number of
  2006 binders, it can deal with arbitrary expressions standing for sets of
  2007 atoms to be avoided.  The only inductive definition we have at the
  2008 moment that needs this generalisation is the typing rule for Lets in
  2009 the algorithm W:
  2010 
  2011  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2012  -----------------------------------------------------------------
  2013          Gamma |- Let x be t1 in t2 : T2
  2014 
  2015 In this rule one wants to avoid all the binders that are introduced by
  2016 "close Gamma T1".  We are looking for other examples where this
  2017 feature might be useful.  Please let us know.
  2018 
  2019 
  2020 *** HOLCF ***
  2021 
  2022 * Reimplemented the simplification procedure for proving continuity
  2023 subgoals.  The new simproc is extensible; users can declare additional
  2024 continuity introduction rules with the attribute [cont2cont].
  2025 
  2026 * The continuity simproc now uses a different introduction rule for
  2027 solving continuity subgoals on terms with lambda abstractions.  In
  2028 some rare cases the new simproc may fail to solve subgoals that the
  2029 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2030 Potential INCOMPATIBILITY.
  2031 
  2032 * Command 'fixrec': specification syntax now conforms to the general
  2033 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2034 examples.  INCOMPATIBILITY.
  2035 
  2036 
  2037 *** ZF ***
  2038 
  2039 * Proof of Zorn's Lemma for partial orders.
  2040 
  2041 
  2042 *** ML ***
  2043 
  2044 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2045 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2046 depends on multithreading, so timouts will not work before Poly/ML
  2047 5.2.1!
  2048 
  2049 * High-level support for concurrent ML programming, see
  2050 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2051 particularly convenient to organize independent functional
  2052 computations.  The concept of "synchronized variables" provides a
  2053 higher-order interface for components with shared state, avoiding the
  2054 delicate details of mutexes and condition variables.  (Requires
  2055 Poly/ML 5.2.1 or later.)
  2056 
  2057 * ML bindings produced via Isar commands are stored within the Isar
  2058 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2059 become thread-safe and work with undo as expected (concerning
  2060 top-level bindings, not side-effects on global references).
  2061 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2062 compiler at runtime; really global bindings need to be given outside a
  2063 theory.  (Requires Poly/ML 5.2 or later.)
  2064 
  2065 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2066 context.  Top-level ML bindings are stored within the proof context in
  2067 a purely sequential fashion, disregarding the nested proof structure.
  2068 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2069 proof.  (Requires Poly/ML 5.2 or later.)
  2070 
  2071 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2072 and Method.setup, as well as Isar commands 'attribute_setup' and
  2073 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2074 existing code accordingly, or use plain 'setup' together with old
  2075 Method.add_method.
  2076 
  2077 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2078 to 'a -> thm, while results are always tagged with an authentic oracle
  2079 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2080 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2081 accordingly.  Note that extra performance may be gained by producing
  2082 the cterm carefully, avoiding slow Thm.cterm_of.
  2083 
  2084 * Simplified interface for defining document antiquotations via
  2085 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2086 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2087 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2088 examples.
  2089 
  2090 * More systematic treatment of long names, abstract name bindings, and
  2091 name space operations.  Basic operations on qualified names have been
  2092 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2093 Long_Name.append.  Old type bstring has been mostly replaced by
  2094 abstract type binding (see structure Binding), which supports precise
  2095 qualification by packages and local theory targets, as well as proper
  2096 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2097 bstring values into Binding.name, or better pass through abstract
  2098 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2099 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2100 
  2101 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2102 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2103 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2104 
  2105 * Disposed old type and term read functions (Sign.read_def_typ,
  2106 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2107 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2108 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2109 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2110 resort for legacy applications.
  2111 
  2112 * Disposed old declarations, tactics, tactic combinators that refer to
  2113 the simpset or claset of an implicit theory (such as Addsimps,
  2114 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2115 embedded ML text, or local_simpset_of with a proper context passed as
  2116 explicit runtime argument.
  2117 
  2118 * Rules and tactics that read instantiations (read_instantiate,
  2119 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2120 context, which is required for parsing and type-checking.  Moreover,
  2121 the variables are specified as plain indexnames, not string encodings
  2122 thereof.  INCOMPATIBILITY.
  2123 
  2124 * Generic Toplevel.add_hook interface allows to analyze the result of
  2125 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2126 for theorem dependency output of transactions resulting in a new
  2127 theory state.
  2128 
  2129 * ML antiquotations: block-structured compilation context indicated by
  2130 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2131 
  2132   @{binding name}                         - basic name binding
  2133   @{let ?pat = term}                      - term abbreviation (HO matching)
  2134   @{note name = fact}                     - fact abbreviation
  2135   @{thm fact}                             - singleton fact (with attributes)
  2136   @{thms fact}                            - general fact (with attributes)
  2137   @{lemma prop by method}                 - singleton goal
  2138   @{lemma prop by meth1 meth2}            - singleton goal
  2139   @{lemma prop1 ... propN by method}      - general goal
  2140   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2141   @{lemma (open) ...}                     - open derivation
  2142 
  2143 
  2144 *** System ***
  2145 
  2146 * The Isabelle "emacs" tool provides a specific interface to invoke
  2147 Proof General / Emacs, with more explicit failure if that is not
  2148 installed (the old isabelle-interface script silently falls back on
  2149 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2150 installation location of the Proof General distribution.
  2151 
  2152 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2153 the Isabelle process into a JVM/Scala application.  See
  2154 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2155 process wrapper has been discontinued.)
  2156 
  2157 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2158 
  2159 * Various status messages (with exact source position information) are
  2160 emitted, if proper markup print mode is enabled.  This allows
  2161 user-interface components to provide detailed feedback on internal
  2162 prover operations.
  2163 
  2164 
  2165 
  2166 New in Isabelle2008 (June 2008)
  2167 -------------------------------
  2168 
  2169 *** General ***
  2170 
  2171 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2172 and updated, with formally checked references as hyperlinks.
  2173 
  2174 * Theory loader: use_thy (and similar operations) no longer set the
  2175 implicit ML context, which was occasionally hard to predict and in
  2176 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2177 provides a proper context already.
  2178 
  2179 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2180 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2181 'use' within a theory file will do the job.
  2182 
  2183 * Name space merge now observes canonical order, i.e. the second space
  2184 is inserted into the first one, while existing entries in the first
  2185 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2186 swap theory imports.
  2187 
  2188 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2189 INCOMPATIBILITY in identifier syntax etc.
  2190 
  2191 * Outer syntax: string tokens no longer admit escaped white space,
  2192 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2193 white space without escapes.
  2194 
  2195 * Outer syntax: string tokens may contain arbitrary character codes
  2196 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2197 "foo_bar".
  2198 
  2199 
  2200 *** Pure ***
  2201 
  2202 * Context-dependent token translations.  Default setup reverts locally
  2203 fixed variables, and adds hilite markup for undeclared frees.
  2204 
  2205 * Unused theorems can be found using the new command 'unused_thms'.
  2206 There are three ways of invoking it:
  2207 
  2208 (1) unused_thms
  2209      Only finds unused theorems in the current theory.
  2210 
  2211 (2) unused_thms thy_1 ... thy_n -
  2212      Finds unused theorems in the current theory and all of its ancestors,
  2213      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2214 
  2215 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2216      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2217      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2218      their ancestors.
  2219 
  2220 In order to increase the readability of the list produced by
  2221 unused_thms, theorems that have been created by a particular instance
  2222 of a theory command such as 'inductive' or 'function' are considered
  2223 to belong to the same "group", meaning that if at least one theorem in
  2224 this group is used, the other theorems in the same group are no longer
  2225 reported as unused.  Moreover, if all theorems in the group are
  2226 unused, only one theorem in the group is displayed.
  2227 
  2228 Note that proof objects have to be switched on in order for
  2229 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2230 usually the case when using Proof General with the default settings).
  2231 
  2232 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2233 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2234 duplicate fact bindings, or even accidental fact duplications.  Note
  2235 that tools may maintain dynamically scoped facts systematically, using
  2236 PureThy.add_thms_dynamic.
  2237 
  2238 * Command 'hide' now allows to hide from "fact" name space as well.
  2239 
  2240 * Eliminated destructive theorem database, simpset, claset, and
  2241 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2242 update of theories within ML code.
  2243 
  2244 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2245 INCOMPATIBILITY, object-logics depending on former Pure require
  2246 additional setup PureThy.old_appl_syntax_setup; object-logics
  2247 depending on former CPure need to refer to Pure.
  2248 
  2249 * Commands 'use' and 'ML' are now purely functional, operating on
  2250 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2251 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2252 INCOMPATIBILITY.
  2253 
  2254 * Command 'setup': discontinued implicit version with ML reference.
  2255 
  2256 * Instantiation target allows for simultaneous specification of class
  2257 instance operations together with an instantiation proof.
  2258 Type-checking phase allows to refer to class operations uniformly.
  2259 See src/HOL/Complex/Complex.thy for an Isar example and
  2260 src/HOL/Library/Eval.thy for an ML example.
  2261 
  2262 * Indexing of literal facts: be more serious about including only
  2263 facts from the visible specification/proof context, but not the
  2264 background context (locale etc.).  Affects `prop` notation and method
  2265 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2266 situations.
  2267 
  2268 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2269 "(open)" option, which used to expose internal bound variables to the
  2270 proof text.
  2271 
  2272 * Isar statements: removed obsolete case "rule_context".
  2273 INCOMPATIBILITY, better use explicit fixes/assumes.
  2274 
  2275 * Locale proofs: default proof step now includes 'unfold_locales';
  2276 hence 'proof' without argument may be used to unfold locale
  2277 predicates.
  2278 
  2279 
  2280 *** Document preparation ***
  2281 
  2282 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2283 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2284 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2285 spot); renamed link color from "darkblue" to "linkcolor" (default
  2286 value unchanged, can be redefined via \definecolor); no longer sets
  2287 "a4paper" option (unnecessary or even intrusive).
  2288 
  2289 * Antiquotation @{lemma A method} proves proposition A by the given
  2290 method (either a method name or a method name plus (optional) method
  2291 arguments in parentheses) and prints A just like @{prop A}.
  2292 
  2293 
  2294 *** HOL ***
  2295 
  2296 * New primrec package.  Specification syntax conforms in style to
  2297 definition/function/....  No separate induction rule is provided.  The
  2298 "primrec" command distinguishes old-style and new-style specifications
  2299 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2300 When adjusting theories, beware: constants stemming from new-style
  2301 primrec specifications have authentic syntax.
  2302 
  2303 * Metis prover is now an order of magnitude faster, and also works
  2304 with multithreading.
  2305 
  2306 * Metis: the maximum number of clauses that can be produced from a
  2307 theorem is now given by the attribute max_clauses.  Theorems that
  2308 exceed this number are ignored, with a warning printed.
  2309 
  2310 * Sledgehammer no longer produces structured proofs by default. To
  2311 enable, declare [[sledgehammer_full = true]].  Attributes
  2312 reconstruction_modulus, reconstruction_sorts renamed
  2313 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2314 
  2315 * Method "induct_scheme" derives user-specified induction rules
  2316 from well-founded induction and completeness of patterns. This factors
  2317 out some operations that are done internally by the function package
  2318 and makes them available separately.  See
  2319 src/HOL/ex/Induction_Scheme.thy for examples.
  2320 
  2321 * More flexible generation of measure functions for termination
  2322 proofs: Measure functions can be declared by proving a rule of the
  2323 form "is_measure f" and giving it the [measure_function] attribute.
  2324 The "is_measure" predicate is logically meaningless (always true), and
  2325 just guides the heuristic.  To find suitable measure functions, the
  2326 termination prover sets up the goal "is_measure ?f" of the appropriate
  2327 type and generates all solutions by prolog-style backwards proof using
  2328 the declared rules.
  2329 
  2330 This setup also deals with rules like 
  2331 
  2332   "is_measure f ==> is_measure (list_size f)"
  2333 
  2334 which accommodates nested datatypes that recurse through lists.
  2335 Similar rules are predeclared for products and option types.
  2336 
  2337 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2338 
  2339   INCOMPATIBILITIES:
  2340 
  2341   - Definitions of overloaded constants on sets have to be replaced by
  2342     definitions on => and bool.
  2343 
  2344   - Some definitions of overloaded operators on sets can now be proved
  2345     using the definitions of the operators on => and bool.  Therefore,
  2346     the following theorems have been renamed:
  2347 
  2348       subset_def   -> subset_eq
  2349       psubset_def  -> psubset_eq
  2350       set_diff_def -> set_diff_eq
  2351       Compl_def    -> Compl_eq
  2352       Sup_set_def  -> Sup_set_eq
  2353       Inf_set_def  -> Inf_set_eq
  2354       sup_set_def  -> sup_set_eq
  2355       inf_set_def  -> inf_set_eq
  2356 
  2357   - Due to the incompleteness of the HO unification algorithm, some
  2358     rules such as subst may require manual instantiation, if some of
  2359     the unknowns in the rule is a set.
  2360 
  2361   - Higher order unification and forward proofs:
  2362     The proof pattern
  2363 
  2364       have "P (S::'a set)" <...>
  2365       then have "EX S. P S" ..
  2366 
  2367     no longer works (due to the incompleteness of the HO unification
  2368     algorithm) and must be replaced by the pattern
  2369 
  2370       have "EX S. P S"
  2371       proof
  2372         show "P S" <...>
  2373       qed
  2374 
  2375   - Calculational reasoning with subst (or similar rules):
  2376     The proof pattern
  2377 
  2378       have "P (S::'a set)" <...>
  2379       also have "S = T" <...>
  2380       finally have "P T" .
  2381 
  2382     no longer works (for similar reasons as the previous example) and
  2383     must be replaced by something like
  2384 
  2385       have "P (S::'a set)" <...>
  2386       moreover have "S = T" <...>
  2387       ultimately have "P T" by simp
  2388 
  2389   - Tactics or packages written in ML code:
  2390     Code performing pattern matching on types via
  2391 
  2392       Type ("set", [T]) => ...
  2393 
  2394     must be rewritten. Moreover, functions like strip_type or
  2395     binder_types no longer return the right value when applied to a
  2396     type of the form
  2397 
  2398       T1 => ... => Tn => U => bool
  2399 
  2400     rather than
  2401 
  2402       T1 => ... => Tn => U set
  2403 
  2404 * Merged theories Wellfounded_Recursion, Accessible_Part and
  2405 Wellfounded_Relations to theory Wellfounded.
  2406 
  2407 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  2408 
  2409 * Class finite no longer treats UNIV as class parameter.  Use class
  2410 enum from theory Library/Enum instead to achieve a similar effect.
  2411 INCOMPATIBILITY.
  2412 
  2413 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  2414 and "Cons".  INCOMPATIBILITY.
  2415 
  2416 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  2417 Potential INCOMPATIBILITY.
  2418 
  2419 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  2420 injective_fst_snd removed, use split_eta and prod_eqI instead.
  2421 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  2422 
  2423 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  2424 the same name in theory Orderings:
  2425 
  2426   less_trans
  2427   less_linear
  2428   le_imp_less_or_eq
  2429   le_less_trans
  2430   less_le_trans
  2431   less_not_sym
  2432   less_asym
  2433 
  2434 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  2435 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  2436 and different variable names.
  2437 
  2438 * Library/Option_ord.thy: Canonical order on option type.
  2439 
  2440 * Library/RBT.thy: Red-black trees, an efficient implementation of
  2441 finite maps.
  2442 
  2443 * Library/Countable.thy: Type class for countable types.
  2444 
  2445 * Theory Int: The representation of numerals has changed.  The infix
  2446 operator BIT and the bit datatype with constructors B0 and B1 have
  2447 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  2448 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  2449 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  2450 accordingly.
  2451 
  2452 * Theory Nat: definition of <= and < on natural numbers no longer
  2453 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  2454 le_def and less_def have disappeared.  Consider lemmas not_less
  2455 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  2456 
  2457 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  2458 (whose purpose mainly is for various fold_set functionals) have been
  2459 abandoned in favor of the existing algebraic classes
  2460 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  2461 lower_semilattice (resp. upper_semilattice) and linorder.
  2462 INCOMPATIBILITY.
  2463 
  2464 * Theory Transitive_Closure: induct and cases rules now declare proper
  2465 case_names ("base" and "step").  INCOMPATIBILITY.
  2466 
  2467 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  2468 lattices.  The form set-specific version is available as
  2469 Inductive.lfp_ordinal_induct_set.
  2470 
  2471 * Renamed theorems "power.simps" to "power_int.simps".
  2472 INCOMPATIBILITY.
  2473 
  2474 * Class semiring_div provides basic abstract properties of semirings
  2475 with division and modulo operations.  Subsumes former class dvd_mod.
  2476 
  2477 * Merged theories IntDef, Numeral and IntArith into unified theory
  2478 Int.  INCOMPATIBILITY.
  2479 
  2480 * Theory Library/Code_Index: type "index" now represents natural
  2481 numbers rather than integers.  INCOMPATIBILITY.
  2482 
  2483 * New class "uminus" with operation "uminus" (split of from class
  2484 "minus" which now only has operation "minus", binary).
  2485 INCOMPATIBILITY.
  2486 
  2487 * Constants "card", "internal_split", "option_map" now with authentic
  2488 syntax.  INCOMPATIBILITY.
  2489 
  2490 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  2491 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  2492 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  2493 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  2494 Sup_set_def, le_def, less_def, option_map_def now with object
  2495 equality.  INCOMPATIBILITY.
  2496 
  2497 * Records. Removed K_record, and replaced it by pure lambda term
  2498 %x. c. The simplifier setup is now more robust against eta expansion.
  2499 INCOMPATIBILITY: in cases explicitly referring to K_record.
  2500 
  2501 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  2502 
  2503 * Library/ListVector: new theory of arithmetic vector operations.
  2504 
  2505 * Library/Order_Relation: new theory of various orderings as sets of
  2506 pairs.  Defines preorders, partial orders, linear orders and
  2507 well-orders on sets and on types.
  2508 
  2509 
  2510 *** ZF ***
  2511 
  2512 * Renamed some theories to allow to loading both ZF and HOL in the
  2513 same session:
  2514 
  2515   Datatype  -> Datatype_ZF
  2516   Inductive -> Inductive_ZF
  2517   Int       -> Int_ZF
  2518   IntDiv    -> IntDiv_ZF
  2519   Nat       -> Nat_ZF
  2520   List      -> List_ZF
  2521   Main      -> Main_ZF
  2522 
  2523 INCOMPATIBILITY: ZF theories that import individual theories below
  2524 Main might need to be adapted.  Regular theory Main is still
  2525 available, as trivial extension of Main_ZF.
  2526 
  2527 
  2528 *** ML ***
  2529 
  2530 * ML within Isar: antiquotation @{const name} or @{const
  2531 name(typargs)} produces statically-checked Const term.
  2532 
  2533 * Functor NamedThmsFun: data is available to the user as dynamic fact
  2534 (of the same name).  Removed obsolete print command.
  2535 
  2536 * Removed obsolete "use_legacy_bindings" function.
  2537 
  2538 * The ``print mode'' is now a thread-local value derived from a global
  2539 template (the former print_mode reference), thus access becomes
  2540 non-critical.  The global print_mode reference is for session
  2541 management only; user-code should use print_mode_value,
  2542 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  2543 
  2544 * Functions system/system_out provide a robust way to invoke external
  2545 shell commands, with propagation of interrupts (requires Poly/ML
  2546 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  2547 
  2548 
  2549 *** System ***
  2550 
  2551 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  2552 in accordance with Proof General 3.7, which prefers GNU emacs.
  2553 
  2554 * isatool tty runs Isabelle process with plain tty interaction;
  2555 optional line editor may be specified via ISABELLE_LINE_EDITOR
  2556 setting, the default settings attempt to locate "ledit" and "rlwrap".
  2557 
  2558 * isatool browser now works with Cygwin as well, using general
  2559 "javapath" function defined in Isabelle process environment.
  2560 
  2561 * YXML notation provides a simple and efficient alternative to
  2562 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  2563 isatool yxml as described in the Isabelle system manual.
  2564 
  2565 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  2566 provides general wrapper for managing an Isabelle process in a robust
  2567 fashion, with ``cooked'' output from stdin/stderr.
  2568 
  2569 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  2570 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  2571 
  2572 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  2573 way of changing the user's settings is via
  2574 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  2575 script.
  2576 
  2577 * Multithreading.max_threads := 0 refers to the number of actual CPU
  2578 cores of the underlying machine, which is a good starting point for
  2579 optimal performance tuning.  The corresponding usedir option -M allows
  2580 "max" as an alias for "0".  WARNING: does not work on certain versions
  2581 of Mac OS (with Poly/ML 5.1).
  2582 
  2583 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  2584 adverse effect of Isabelle flooding interactive front-ends (notably
  2585 ProofGeneral / XEmacs).
  2586 
  2587 
  2588 
  2589 New in Isabelle2007 (November 2007)
  2590 -----------------------------------
  2591 
  2592 *** General ***
  2593 
  2594 * More uniform information about legacy features, notably a
  2595 warning/error of "Legacy feature: ...", depending on the state of the
  2596 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  2597 legacy features will disappear eventually.
  2598 
  2599 * Theory syntax: the header format ``theory A = B + C:'' has been
  2600 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  2601 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  2602 
  2603 * Theory syntax: the old non-Isar theory file format has been
  2604 discontinued altogether.  Note that ML proof scripts may still be used
  2605 with Isar theories; migration is usually quite simple with the ML
  2606 function use_legacy_bindings.  INCOMPATIBILITY.
  2607 
  2608 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  2609 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  2610 quotes.
  2611 
  2612 * Theory loader: be more serious about observing the static theory
  2613 header specifications (including optional directories), but not the
  2614 accidental file locations of previously successful loads.  The strict
  2615 update policy of former update_thy is now already performed by
  2616 use_thy, so the former has been removed; use_thys updates several
  2617 theories simultaneously, just as 'imports' within a theory header
  2618 specification, but without merging the results.  Potential
  2619 INCOMPATIBILITY: may need to refine theory headers and commands
  2620 ROOT.ML which depend on load order.
  2621 
  2622 * Theory loader: optional support for content-based file
  2623 identification, instead of the traditional scheme of full physical
  2624 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  2625 (cf. the system manual).  The new scheme allows to work with
  2626 non-finished theories in persistent session images, such that source
  2627 files may be moved later on without requiring reloads.
  2628 
  2629 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2630 file (with the same base name as the theory) are considered a legacy
  2631 feature, which will disappear eventually. Even now, the theory loader
  2632 no longer maintains dependencies on such files.
  2633 
  2634 * Syntax: the scope for resolving ambiguities via type-inference is
  2635 now limited to individual terms, instead of whole simultaneous
  2636 specifications as before. This greatly reduces the complexity of the
  2637 syntax module and improves flexibility by separating parsing and
  2638 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  2639 'fixes' etc.) are required in rare situations.
  2640 
  2641 * Syntax: constants introduced by new-style packages ('definition',
  2642 'abbreviation' etc.) are passed through the syntax module in
  2643 ``authentic mode''. This means that associated mixfix annotations
  2644 really stick to such constants, independently of potential name space
  2645 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  2646 trees are represented slightly differently, may need to adapt syntax
  2647 translations accordingly. Use CONST marker in 'translations' and
  2648 @{const_syntax} antiquotation in 'parse_translation' etc.
  2649 
  2650 * Legacy goal package: reduced interface to the bare minimum required
  2651 to keep existing proof scripts running.  Most other user-level
  2652 functions are now part of the OldGoals structure, which is *not* open
  2653 by default (consider isatool expandshort before open OldGoals).
  2654 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  2655 these tend to cause confusion about the actual goal (!) context being
  2656 used here, which is not necessarily the same as the_context().
  2657 
  2658 * Command 'find_theorems': supports "*" wild-card in "name:"
  2659 criterion; "with_dups" option.  Certain ProofGeneral versions might
  2660 support a specific search form (see ProofGeneral/CHANGES).
  2661 
  2662 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  2663 by default, which means that "prems" (and also "fixed variables") are
  2664 suppressed from proof state output.  Note that the ProofGeneral
  2665 settings mechanism allows to change and save options persistently, but
  2666 older versions of Isabelle will fail to start up if a negative prems
  2667 limit is imposed.
  2668 
  2669 * Local theory targets may be specified by non-nested blocks of
  2670 ``context/locale/class ... begin'' followed by ``end''.  The body may
  2671 contain definitions, theorems etc., including any derived mechanism
  2672 that has been implemented on top of these primitives.  This concept
  2673 generalizes the existing ``theorem (in ...)'' towards more versatility
  2674 and scalability.
  2675 
  2676 * Proof General interface: proper undo of final 'end' command;
  2677 discontinued Isabelle/classic mode (ML proof scripts).
  2678 
  2679 
  2680 *** Document preparation ***
  2681 
  2682 * Added antiquotation @{theory name} which prints the given name,
  2683 after checking that it refers to a valid ancestor theory in the
  2684 current context.
  2685 
  2686 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  2687 check the given source text as ML type/structure, printing verbatim.
  2688 
  2689 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  2690 "c args == rhs" given in the current context.  (Any number of
  2691 arguments may be given on the LHS.)
  2692 
  2693 
  2694 *** Pure ***
  2695 
  2696 * The 'class' package offers a combination of axclass and locale to
  2697 achieve Haskell-like type classes in Isabelle.  Definitions and
  2698 theorems within a class context produce both relative results (with
  2699 implicit parameters according to the locale context), and polymorphic
  2700 constants with qualified polymorphism (according to the class
  2701 context).  Within the body context of a 'class' target, a separate
  2702 syntax layer ("user space type system") takes care of converting
  2703 between global polymorphic consts and internal locale representation.
  2704 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  2705 "isatool doc classes" provides a tutorial.
  2706 
  2707 * Generic code generator framework allows to generate executable
  2708 code for ML and Haskell (including Isabelle classes).  A short usage
  2709 sketch:
  2710 
  2711     internal compilation:
  2712         export_code <list of constants (term syntax)> in SML
  2713     writing SML code to a file:
  2714         export_code <list of constants (term syntax)> in SML <filename>
  2715     writing OCaml code to a file:
  2716         export_code <list of constants (term syntax)> in OCaml <filename>
  2717     writing Haskell code to a bunch of files:
  2718         export_code <list of constants (term syntax)> in Haskell <filename>
  2719 
  2720     evaluating closed propositions to True/False using code generation:
  2721         method ``eval''
  2722 
  2723 Reasonable default setup of framework in HOL.
  2724 
  2725 Theorem attributs for selecting and transforming function equations theorems:
  2726 
  2727     [code fun]:        select a theorem as function equation for a specific constant
  2728     [code fun del]:    deselect a theorem as function equation for a specific constant
  2729     [code inline]:     select an equation theorem for unfolding (inlining) in place
  2730     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  2731 
  2732 User-defined serializations (target in {SML, OCaml, Haskell}):
  2733 
  2734     code_const <and-list of constants (term syntax)>
  2735       {(target) <and-list of const target syntax>}+
  2736 
  2737     code_type <and-list of type constructors>
  2738       {(target) <and-list of type target syntax>}+
  2739 
  2740     code_instance <and-list of instances>
  2741       {(target)}+
  2742         where instance ::= <type constructor> :: <class>
  2743 
  2744     code_class <and_list of classes>
  2745       {(target) <and-list of class target syntax>}+
  2746         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  2747 
  2748 code_instance and code_class only are effective to target Haskell.
  2749 
  2750 For example usage see src/HOL/ex/Codegenerator.thy and
  2751 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  2752 generation from Isabelle/HOL theories is available via "isatool doc
  2753 codegen".
  2754 
  2755 * Code generator: consts in 'consts_code' Isar commands are now
  2756 referred to by usual term syntax (including optional type
  2757 annotations).
  2758 
  2759 * Command 'no_translations' removes translation rules from theory
  2760 syntax.
  2761 
  2762 * Overloaded definitions are now actually checked for acyclic
  2763 dependencies.  The overloading scheme is slightly more general than
  2764 that of Haskell98, although Isabelle does not demand an exact
  2765 correspondence to type class and instance declarations.
  2766 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  2767 exotic versions of overloading -- at the discretion of the user!
  2768 
  2769 Polymorphic constants are represented via type arguments, i.e. the
  2770 instantiation that matches an instance against the most general
  2771 declaration given in the signature.  For example, with the declaration
  2772 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  2773 as c(nat).  Overloading is essentially simultaneous structural
  2774 recursion over such type arguments.  Incomplete specification patterns
  2775 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  2776 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  2777 Command 'print_theory' outputs the normalized system of recursive
  2778 equations, see section "definitions".
  2779 
  2780 * Configuration options are maintained within the theory or proof
  2781 context (with name and type bool/int/string), providing a very simple
  2782 interface to a poor-man's version of general context data.  Tools may
  2783 declare options in ML (e.g. using Attrib.config_int) and then refer to
  2784 these values using Config.get etc.  Users may change options via an
  2785 associated attribute of the same name.  This form of context
  2786 declaration works particularly well with commands 'declare' or
  2787 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  2788 very easy to avoid global references, which would not observe Isar
  2789 toplevel undo/redo and fail to work with multithreading.
  2790 
  2791 Various global ML references of Pure and HOL have been turned into
  2792 configuration options:
  2793 
  2794   Unify.search_bound		unify_search_bound
  2795   Unify.trace_bound		unify_trace_bound
  2796   Unify.trace_simp		unify_trace_simp
  2797   Unify.trace_types		unify_trace_types
  2798   Simplifier.simp_depth_limit	simp_depth_limit
  2799   Blast.depth_limit		blast_depth_limit
  2800   DatatypeProp.dtK		datatype_distinctness_limit
  2801   fast_arith_neq_limit  	fast_arith_neq_limit
  2802   fast_arith_split_limit	fast_arith_split_limit
  2803 
  2804 * Named collections of theorems may be easily installed as context
  2805 data using the functor NamedThmsFun (see also
  2806 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  2807 attributes; there is also a toplevel print command.  This facility is
  2808 just a common case of general context data, which is the preferred way
  2809 for anything more complex than just a list of facts in canonical
  2810 order.
  2811 
  2812 * Isar: command 'declaration' augments a local theory by generic
  2813 declaration functions written in ML.  This enables arbitrary content
  2814 being added to the context, depending on a morphism that tells the
  2815 difference of the original declaration context wrt. the application
  2816 context encountered later on.
  2817 
  2818 * Isar: proper interfaces for simplification procedures.  Command
  2819 'simproc_setup' declares named simprocs (with match patterns, and body
  2820 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  2821 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  2822 
  2823 * Isar: an extra pair of brackets around attribute declarations
  2824 abbreviates a theorem reference involving an internal dummy fact,
  2825 which will be ignored later --- only the effect of the attribute on
  2826 the background context will persist.  This form of in-place
  2827 declarations is particularly useful with commands like 'declare' and
  2828 'using', for example ``have A using [[simproc a]] by simp''.
  2829 
  2830 * Isar: method "assumption" (and implicit closing of subproofs) now
  2831 takes simple non-atomic goal assumptions into account: after applying
  2832 an assumption as a rule the resulting subgoals are solved by atomic
  2833 assumption steps.  This is particularly useful to finish 'obtain'
  2834 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  2835 without referring to the original premise "!!x. P x ==> thesis" in the
  2836 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  2837 more permissive.
  2838 
  2839 * Isar: implicit use of prems from the Isar proof context is
  2840 considered a legacy feature.  Common applications like ``have A .''
  2841 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  2842 referencing facts explicitly here improves readability and
  2843 maintainability of proof texts.
  2844 
  2845 * Isar: improper proof element 'guess' is like 'obtain', but derives
  2846 the obtained context from the course of reasoning!  For example:
  2847 
  2848   assume "EX x y. A x & B y"   -- "any previous fact"
  2849   then guess x and y by clarify
  2850 
  2851 This technique is potentially adventurous, depending on the facts and
  2852 proof tools being involved here.
  2853 
  2854 * Isar: known facts from the proof context may be specified as literal
  2855 propositions, using ASCII back-quote syntax.  This works wherever
  2856 named facts used to be allowed so far, in proof commands, proof
  2857 methods, attributes etc.  Literal facts are retrieved from the context
  2858 according to unification of type and term parameters.  For example,
  2859 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  2860 theorems in the current context, then these are valid literal facts:
  2861 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  2862 
  2863 There is also a proof method "fact" which does the same composition
  2864 for explicit goal states, e.g. the following proof texts coincide with
  2865 certain special cases of literal facts:
  2866 
  2867   have "A" by fact                 ==  note `A`
  2868   have "A ==> B" by fact           ==  note `A ==> B`
  2869   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  2870   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  2871 
  2872 * Isar: ":" (colon) is no longer a symbolic identifier character in
  2873 outer syntax.  Thus symbolic identifiers may be used without
  2874 additional white space in declarations like this: ``assume *: A''.
  2875 
  2876 * Isar: 'print_facts' prints all local facts of the current context,
  2877 both named and unnamed ones.
  2878 
  2879 * Isar: 'def' now admits simultaneous definitions, e.g.:
  2880 
  2881   def x == "t" and y == "u"
  2882 
  2883 * Isar: added command 'unfolding', which is structurally similar to
  2884 'using', but affects both the goal state and facts by unfolding given
  2885 rewrite rules.  Thus many occurrences of the 'unfold' method or
  2886 'unfolded' attribute may be replaced by first-class proof text.
  2887 
  2888 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  2889 and command 'unfolding' now all support object-level equalities
  2890 (potentially conditional).  The underlying notion of rewrite rule is
  2891 analogous to the 'rule_format' attribute, but *not* that of the
  2892 Simplifier (which is usually more generous).
  2893 
  2894 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  2895 premises of a theorem by n. Useful in conjunction with drule.
  2896 
  2897 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  2898 method expression within a sandbox consisting of the first N
  2899 sub-goals, which need to exist.  For example, ``simp_all [3]''
  2900 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  2901 simplifies all new goals that emerge from applying rule foo to the
  2902 originally first one.
  2903 
  2904 * Isar: schematic goals are no longer restricted to higher-order
  2905 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  2906 expected.
  2907 
  2908 * Isar: the conclusion of a long theorem statement is now either
  2909 'shows' (a simultaneous conjunction, as before), or 'obtains'
  2910 (essentially a disjunction of cases with local parameters and
  2911 assumptions).  The latter allows to express general elimination rules
  2912 adequately; in this notation common elimination rules look like this:
  2913 
  2914   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  2915     assumes "EX x. P x"
  2916     obtains x where "P x"
  2917 
  2918   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  2919     assumes "A & B"
  2920     obtains A and B
  2921 
  2922   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  2923     assumes "A | B"
  2924     obtains
  2925       A
  2926     | B
  2927 
  2928 The subsequent classical rules even refer to the formal "thesis"
  2929 explicitly:
  2930 
  2931   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  2932     obtains "~ thesis"
  2933 
  2934   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  2935     obtains "thesis ==> something"
  2936 
  2937 The actual proof of an 'obtains' statement is analogous to that of the
  2938 Isar proof element 'obtain', only that there may be several cases.
  2939 Optional case names may be specified in parentheses; these will be
  2940 available both in the present proof and as annotations in the
  2941 resulting rule, for later use with the 'cases' method (cf. attribute
  2942 case_names).
  2943 
  2944 * Isar: the assumptions of a long theorem statement are available as
  2945 "assms" fact in the proof context.  This is more appropriate than the
  2946 (historical) "prems", which refers to all assumptions of the current
  2947 context, including those from the target locale, proof body etc.
  2948 
  2949 * Isar: 'print_statement' prints theorems from the current theory or
  2950 proof context in long statement form, according to the syntax of a
  2951 top-level lemma.
  2952 
  2953 * Isar: 'obtain' takes an optional case name for the local context
  2954 introduction rule (default "that").
  2955 
  2956 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  2957 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  2958 to occur.
  2959 
  2960 * Pure: syntax "CONST name" produces a fully internalized constant
  2961 according to the current context.  This is particularly useful for
  2962 syntax translations that should refer to internal constant
  2963 representations independently of name spaces.
  2964 
  2965 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  2966 instead of "FOO ". This allows multiple binder declarations to coexist
  2967 in the same context.  INCOMPATIBILITY.
  2968 
  2969 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  2970 primitive that also works in a locale context (both for constants and
  2971 fixed variables). Type declaration and internal syntactic representation
  2972 of given constants retrieved from the context. Likewise, the
  2973 'no_notation' command allows to remove given syntax annotations from the
  2974 current context.
  2975 
  2976 * Isar/locales: new derived specification elements 'axiomatization',
  2977 'definition', 'abbreviation', which support type-inference, admit
  2978 object-level specifications (equality, equivalence).  See also the
  2979 isar-ref manual.  Examples:
  2980 
  2981   axiomatization
  2982     eq  (infix "===" 50) where
  2983     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  2984 
  2985   definition "f x y = x + y + 1"
  2986   definition g where "g x = f x x"
  2987 
  2988   abbreviation
  2989     neq  (infix "=!=" 50) where
  2990     "x =!= y == ~ (x === y)"
  2991 
  2992 These specifications may be also used in a locale context.  Then the
  2993 constants being introduced depend on certain fixed parameters, and the
  2994 constant name is qualified by the locale base name.  An internal
  2995 abbreviation takes care for convenient input and output, making the
  2996 parameters implicit and using the original short name.  See also
  2997 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  2998 entities from a monomorphic theory.
  2999 
  3000 Presently, abbreviations are only available 'in' a target locale, but
  3001 not inherited by general import expressions.  Also note that
  3002 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3003 'translations' in common applications.  The "no_abbrevs" print mode
  3004 prevents folding of abbreviations in term output.
  3005 
  3006 Concrete syntax is attached to specified constants in internal form,
  3007 independently of name spaces.  The parse tree representation is
  3008 slightly different -- use 'notation' instead of raw 'syntax', and
  3009 'translations' with explicit "CONST" markup to accommodate this.
  3010 
  3011 * Pure/Isar: unified syntax for new-style specification mechanisms
  3012 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3013 full type inference and dummy patterns ("_").  For example:
  3014 
  3015   definition "K x _ = x"
  3016 
  3017   inductive conj for A B
  3018   where "A ==> B ==> conj A B"
  3019 
  3020 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3021 the current context.  Print mode "no_abbrevs" prevents inversion of
  3022 abbreviations on output.
  3023 
  3024 * Isar/locales: improved parameter handling: use of locales "var" and
  3025 "struct" no longer necessary; - parameter renamings are no longer
  3026 required to be injective.  For example, this allows to define
  3027 endomorphisms as locale endom = homom mult mult h.
  3028 
  3029 * Isar/locales: changed the way locales with predicates are defined.
  3030 Instead of accumulating the specification, the imported expression is
  3031 now an interpretation.  INCOMPATIBILITY: different normal form of
  3032 locale expressions.  In particular, in interpretations of locales with
  3033 predicates, goals repesenting already interpreted fragments are not
  3034 removed automatically.  Use methods `intro_locales' and
  3035 `unfold_locales'; see below.
  3036 
  3037 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3038 provide backward reasoning on locales predicates.  The methods are
  3039 aware of interpretations and discharge corresponding goals.
  3040 `intro_locales' is less aggressive then `unfold_locales' and does not
  3041 unfold predicates to assumptions.
  3042 
  3043 * Isar/locales: the order in which locale fragments are accumulated
  3044 has changed.  This enables to override declarations from fragments due
  3045 to interpretations -- for example, unwanted simp rules.
  3046 
  3047 * Isar/locales: interpretation in theories and proof contexts has been
  3048 extended.  One may now specify (and prove) equations, which are
  3049 unfolded in interpreted theorems.  This is useful for replacing
  3050 defined concepts (constants depending on locale parameters) by
  3051 concepts already existing in the target context.  Example:
  3052 
  3053   interpretation partial_order ["op <= :: [int, int] => bool"]
  3054     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3055 
  3056 Typically, the constant `partial_order.less' is created by a
  3057 definition specification element in the context of locale
  3058 partial_order.
  3059 
  3060 * Method "induct": improved internal context management to support
  3061 local fixes and defines on-the-fly. Thus explicit meta-level
  3062 connectives !!  and ==> are rarely required anymore in inductive goals
  3063 (using object-logic connectives for this purpose has been long
  3064 obsolete anyway). Common proof patterns are explained in
  3065 src/HOL/Induct/Common_Patterns.thy, see also
  3066 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3067 examples.
  3068 
  3069 * Method "induct": improved handling of simultaneous goals. Instead of
  3070 introducing object-level conjunction, the statement is now split into
  3071 several conclusions, while the corresponding symbolic cases are nested
  3072 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3073 see src/HOL/Induct/Common_Patterns.thy, for example.
  3074 
  3075 * Method "induct": mutual induction rules are now specified as a list
  3076 of rule sharing the same induction cases. HOL packages usually provide
  3077 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3078 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3079 mutual induction rules differently, i.e. like this:
  3080 
  3081   (induct rule: foo_bar.inducts)
  3082   (induct set: foo bar)
  3083   (induct pred: foo bar)
  3084   (induct type: foo bar)
  3085 
  3086 The ML function ProjectRule.projections turns old-style rules into the
  3087 new format.
  3088 
  3089 * Method "coinduct": dual of induction, see
  3090 src/HOL/Library/Coinductive_List.thy for various examples.
  3091 
  3092 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3093 considered a legacy feature.
  3094 
  3095 * Attribute "symmetric" produces result with standardized schematic
  3096 variables (index 0).  Potential INCOMPATIBILITY.
  3097 
  3098 * Simplifier: by default the simplifier trace only shows top level
  3099 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3100 default. Thus there is less danger of being flooded by the trace. The
  3101 trace indicates where parts have been suppressed.
  3102   
  3103 * Provers/classical: removed obsolete classical version of elim_format
  3104 attribute; classical elim/dest rules are now treated uniformly when
  3105 manipulating the claset.
  3106 
  3107 * Provers/classical: stricter checks to ensure that supplied intro,
  3108 dest and elim rules are well-formed; dest and elim rules must have at
  3109 least one premise.
  3110 
  3111 * Provers/classical: attributes dest/elim/intro take an optional
  3112 weight argument for the rule (just as the Pure versions).  Weights are
  3113 ignored by automated tools, but determine the search order of single
  3114 rule steps.
  3115 
  3116 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3117 where the body does not mention the bound variable.  Note that dummy
  3118 patterns implicitly depend on their context of bounds, which makes
  3119 "{_. _}" match any set comprehension as expected.  Potential
  3120 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3121 constant "_idtdummy" in the binding position.
  3122 
  3123 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3124 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3125 for example "A -> B" => "Pi A (%_. B)".
  3126 
  3127 * Pure: 'class_deps' command visualizes the subclass relation, using
  3128 the graph browser tool.
  3129 
  3130 * Pure: 'print_theory' now suppresses certain internal declarations by
  3131 default; use '!' option for full details.
  3132 
  3133 
  3134 *** HOL ***
  3135 
  3136 * Method "metis" proves goals by applying the Metis general-purpose
  3137 resolution prover (see also http://gilith.com/software/metis/).
  3138 Examples are in the directory MetisExamples.  WARNING: the
  3139 Isabelle/HOL-Metis integration does not yet work properly with
  3140 multi-threading.
  3141   
  3142 * Command 'sledgehammer' invokes external automatic theorem provers as
  3143 background processes.  It generates calls to the "metis" method if
  3144 successful. These can be pasted into the proof.  Users do not have to
  3145 wait for the automatic provers to return.  WARNING: does not really
  3146 work with multi-threading.
  3147 
  3148 * New "auto_quickcheck" feature tests outermost goal statements for
  3149 potential counter-examples.  Controlled by ML references
  3150 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3151 5000 milliseconds).  Fails silently if statements is outside of
  3152 executable fragment, or any other codgenerator problem occurs.
  3153 
  3154 * New constant "undefined" with axiom "undefined x = undefined".
  3155 
  3156 * Added class "HOL.eq", allowing for code generation with polymorphic
  3157 equality.
  3158 
  3159 * Some renaming of class constants due to canonical name prefixing in
  3160 the new 'class' package:
  3161 
  3162     HOL.abs ~> HOL.abs_class.abs
  3163     HOL.divide ~> HOL.divide_class.divide
  3164     0 ~> HOL.zero_class.zero
  3165     1 ~> HOL.one_class.one
  3166     op + ~> HOL.plus_class.plus
  3167     op - ~> HOL.minus_class.minus
  3168     uminus ~> HOL.minus_class.uminus
  3169     op * ~> HOL.times_class.times
  3170     op < ~> HOL.ord_class.less
  3171     op <= > HOL.ord_class.less_eq
  3172     Nat.power ~> Power.power_class.power
  3173     Nat.size ~> Nat.size_class.size
  3174     Numeral.number_of ~> Numeral.number_class.number_of
  3175     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3176     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3177     Orderings.min ~> Orderings.ord_class.min
  3178     Orderings.max ~> Orderings.ord_class.max
  3179     Divides.op div ~> Divides.div_class.div
  3180     Divides.op mod ~> Divides.div_class.mod
  3181     Divides.op dvd ~> Divides.div_class.dvd
  3182 
  3183 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3184 
  3185 a) User-defined constants using any of the names "plus", "minus",
  3186 "times", "less" or "less_eq". The standard syntax translations for
  3187 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3188 names.
  3189 
  3190 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3191 INCOMPATIBILITY: use more specific names.
  3192 
  3193 c) Permutative equations (e.g. "a + b = b + a")
  3194 Since the change of names also changes the order of terms, permutative
  3195 rewrite rules may get applied in a different order. Experience shows
  3196 that this is rarely the case (only two adaptions in the whole Isabelle
  3197 distribution).  INCOMPATIBILITY: rewrite proofs
  3198 
  3199 d) ML code directly refering to constant names
  3200 This in general only affects hand-written proof tactics, simprocs and
  3201 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3202 Consider using @{const_name} antiquotation.
  3203 
  3204 * New class "default" with associated constant "default".
  3205 
  3206 * Function "sgn" is now overloaded and available on int, real, complex
  3207 (and other numeric types), using class "sgn".  Two possible defs of
  3208 sgn are given as equational assumptions in the classes sgn_if and
  3209 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3210 INCOMPATIBILITY.
  3211 
  3212 * Locale "partial_order" now unified with class "order" (cf. theory
  3213 Orderings), added parameter "less".  INCOMPATIBILITY.
  3214 
  3215 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3216 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3217 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3218 
  3219 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3220 changed order of proof goals in instance proofs.
  3221 
  3222 * The transitivity reasoner for partial and linear orders is set up
  3223 for classes "order" and "linorder".  Instances of the reasoner are available
  3224 in all contexts importing or interpreting the corresponding locales.
  3225 Method "order" invokes the reasoner separately; the reasoner
  3226 is also integrated with the Simplifier as a solver.  Diagnostic
  3227 command 'print_orders' shows the available instances of the reasoner
  3228 in the current context.
  3229 
  3230 * Localized monotonicity predicate in theory "Orderings"; integrated
  3231 lemmas max_of_mono and min_of_mono with this predicate.
  3232 INCOMPATIBILITY.
  3233 
  3234 * Formulation of theorem "dense" changed slightly due to integration
  3235 with new class dense_linear_order.
  3236 
  3237 * Uniform lattice theory development in HOL.
  3238 
  3239     constants "meet" and "join" now named "inf" and "sup"
  3240     constant "Meet" now named "Inf"
  3241 
  3242     classes "meet_semilorder" and "join_semilorder" now named
  3243       "lower_semilattice" and "upper_semilattice"
  3244     class "lorder" now named "lattice"
  3245     class "comp_lat" now named "complete_lattice"
  3246 
  3247     Instantiation of lattice classes allows explicit definitions
  3248     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3249 
  3250   INCOMPATIBILITY.  Theorem renames:
  3251 
  3252     meet_left_le            ~> inf_le1
  3253     meet_right_le           ~> inf_le2
  3254     join_left_le            ~> sup_ge1
  3255     join_right_le           ~> sup_ge2
  3256     meet_join_le            ~> inf_sup_ord
  3257     le_meetI                ~> le_infI
  3258     join_leI                ~> le_supI
  3259     le_meet                 ~> le_inf_iff
  3260     le_join                 ~> ge_sup_conv
  3261     meet_idempotent         ~> inf_idem
  3262     join_idempotent         ~> sup_idem
  3263     meet_comm               ~> inf_commute
  3264     join_comm               ~> sup_commute
  3265     meet_leI1               ~> le_infI1
  3266     meet_leI2               ~> le_infI2
  3267     le_joinI1               ~> le_supI1
  3268     le_joinI2               ~> le_supI2
  3269     meet_assoc              ~> inf_assoc
  3270     join_assoc              ~> sup_assoc
  3271     meet_left_comm          ~> inf_left_commute
  3272     meet_left_idempotent    ~> inf_left_idem
  3273     join_left_comm          ~> sup_left_commute
  3274     join_left_idempotent    ~> sup_left_idem
  3275     meet_aci                ~> inf_aci
  3276     join_aci                ~> sup_aci
  3277     le_def_meet             ~> le_iff_inf
  3278     le_def_join             ~> le_iff_sup
  3279     join_absorp2            ~> sup_absorb2
  3280     join_absorp1            ~> sup_absorb1
  3281     meet_absorp1            ~> inf_absorb1
  3282     meet_absorp2            ~> inf_absorb2
  3283     meet_join_absorp        ~> inf_sup_absorb
  3284     join_meet_absorp        ~> sup_inf_absorb
  3285     distrib_join_le         ~> distrib_sup_le
  3286     distrib_meet_le         ~> distrib_inf_le
  3287 
  3288     add_meet_distrib_left   ~> add_inf_distrib_left
  3289     add_join_distrib_left   ~> add_sup_distrib_left
  3290     is_join_neg_meet        ~> is_join_neg_inf
  3291     is_meet_neg_join        ~> is_meet_neg_sup
  3292     add_meet_distrib_right  ~> add_inf_distrib_right
  3293     add_join_distrib_right  ~> add_sup_distrib_right
  3294     add_meet_join_distribs  ~> add_sup_inf_distribs
  3295     join_eq_neg_meet        ~> sup_eq_neg_inf
  3296     meet_eq_neg_join        ~> inf_eq_neg_sup
  3297     add_eq_meet_join        ~> add_eq_inf_sup
  3298     meet_0_imp_0            ~> inf_0_imp_0
  3299     join_0_imp_0            ~> sup_0_imp_0
  3300     meet_0_eq_0             ~> inf_0_eq_0
  3301     join_0_eq_0             ~> sup_0_eq_0
  3302     neg_meet_eq_join        ~> neg_inf_eq_sup
  3303     neg_join_eq_meet        ~> neg_sup_eq_inf
  3304     join_eq_if              ~> sup_eq_if
  3305 
  3306     mono_meet               ~> mono_inf
  3307     mono_join               ~> mono_sup
  3308     meet_bool_eq            ~> inf_bool_eq
  3309     join_bool_eq            ~> sup_bool_eq
  3310     meet_fun_eq             ~> inf_fun_eq
  3311     join_fun_eq             ~> sup_fun_eq
  3312     meet_set_eq             ~> inf_set_eq
  3313     join_set_eq             ~> sup_set_eq
  3314     meet1_iff               ~> inf1_iff
  3315     meet2_iff               ~> inf2_iff
  3316     meet1I                  ~> inf1I
  3317     meet2I                  ~> inf2I
  3318     meet1D1                 ~> inf1D1
  3319     meet2D1                 ~> inf2D1
  3320     meet1D2                 ~> inf1D2
  3321     meet2D2                 ~> inf2D2
  3322     meet1E                  ~> inf1E
  3323     meet2E                  ~> inf2E
  3324     join1_iff               ~> sup1_iff
  3325     join2_iff               ~> sup2_iff
  3326     join1I1                 ~> sup1I1
  3327     join2I1                 ~> sup2I1
  3328     join1I1                 ~> sup1I1
  3329     join2I2                 ~> sup1I2
  3330     join1CI                 ~> sup1CI
  3331     join2CI                 ~> sup2CI
  3332     join1E                  ~> sup1E
  3333     join2E                  ~> sup2E
  3334 
  3335     is_meet_Meet            ~> is_meet_Inf
  3336     Meet_bool_def           ~> Inf_bool_def
  3337     Meet_fun_def            ~> Inf_fun_def
  3338     Meet_greatest           ~> Inf_greatest
  3339     Meet_lower              ~> Inf_lower
  3340     Meet_set_def            ~> Inf_set_def
  3341 
  3342     Sup_def                 ~> Sup_Inf
  3343     Sup_bool_eq             ~> Sup_bool_def
  3344     Sup_fun_eq              ~> Sup_fun_def
  3345     Sup_set_eq              ~> Sup_set_def
  3346 
  3347     listsp_meetI            ~> listsp_infI
  3348     listsp_meet_eq          ~> listsp_inf_eq
  3349 
  3350     meet_min                ~> inf_min
  3351     join_max                ~> sup_max
  3352 
  3353 * Added syntactic class "size"; overloaded constant "size" now has
  3354 type "'a::size ==> bool"
  3355 
  3356 * Internal reorganisation of `size' of datatypes: size theorems
  3357 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3358 simplification rules by default!); theorems "prod.size" now named
  3359 "*.size".
  3360 
  3361 * Class "div" now inherits from class "times" rather than "type".
  3362 INCOMPATIBILITY.
  3363 
  3364 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  3365 Linorder etc.  have disappeared; operations defined in terms of
  3366 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  3367 
  3368 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  3369 
  3370 * HOL-Word: New extensive library and type for generic, fixed size
  3371 machine words, with arithemtic, bit-wise, shifting and rotating
  3372 operations, reflection into int, nat, and bool lists, automation for
  3373 linear arithmetic (by automatic reflection into nat or int), including
  3374 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  3375 arithmetic type classes, supporting automatic simplification of
  3376 numerals on all operations.
  3377 
  3378 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  3379 
  3380 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  3381 
  3382 * Code generator library theories:
  3383   - Code_Integer represents HOL integers by big integer literals in target
  3384     languages.
  3385   - Code_Char represents HOL characters by character literals in target
  3386     languages.
  3387   - Code_Char_chr like Code_Char, but also offers treatment of character
  3388     codes; includes Code_Integer.
  3389   - Executable_Set allows to generate code for finite sets using lists.
  3390   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  3391     denominator).
  3392   - Executable_Real implements a subset of real numbers, namly those
  3393     representable by rational numbers.
  3394   - Efficient_Nat implements natural numbers by integers, which in general will
  3395     result in higher efficency; pattern matching with 0/Suc is eliminated;
  3396     includes Code_Integer.
  3397   - Code_Index provides an additional datatype index which is mapped to
  3398     target-language built-in integers.
  3399   - Code_Message provides an additional datatype message_string which is isomorphic to
  3400     strings; messages are mapped to target-language strings.
  3401 
  3402 * New package for inductive predicates
  3403 
  3404   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  3405 
  3406     inductive
  3407       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3408       for z_1 :: U_1 and ... and z_n :: U_m
  3409     where
  3410       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3411     | ...
  3412 
  3413   with full support for type-inference, rather than
  3414 
  3415     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3416 
  3417     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3418     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3419 
  3420     inductive "s z_1 ... z_m"
  3421     intros
  3422       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3423       ...
  3424 
  3425   For backward compatibility, there is a wrapper allowing inductive
  3426   sets to be defined with the new package via
  3427 
  3428     inductive_set
  3429       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3430       for z_1 :: U_1 and ... and z_n :: U_m
  3431     where
  3432       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3433     | ...
  3434 
  3435   or
  3436 
  3437     inductive_set
  3438       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3439       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3440       for z_1 :: U_1 and ... and z_n :: U_m
  3441     where
  3442       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3443     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3444     | ...
  3445 
  3446   if the additional syntax "p ..." is required.
  3447 
  3448   Numerous examples can be found in the subdirectories src/HOL/Auth,
  3449   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  3450 
  3451   INCOMPATIBILITIES:
  3452 
  3453   - Since declaration and definition of inductive sets or predicates
  3454     is no longer separated, abbreviations involving the newly
  3455     introduced sets or predicates must be specified together with the
  3456     introduction rules after the 'where' keyword (see above), rather
  3457     than before the actual inductive definition.
  3458 
  3459   - The variables in induction and elimination rules are now
  3460     quantified in the order of their occurrence in the introduction
  3461     rules, rather than in alphabetical order. Since this may break
  3462     some proofs, these proofs either have to be repaired, e.g. by
  3463     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  3464     statements of the form
  3465 
  3466       case (rule_i a_i_1 ... a_i_{k_i})
  3467 
  3468     or the old order of quantification has to be restored by explicitly adding
  3469     meta-level quantifiers in the introduction rules, i.e.
  3470 
  3471       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  3472 
  3473   - The format of the elimination rules is now
  3474 
  3475       p z_1 ... z_m x_1 ... x_n ==>
  3476         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3477         ==> ... ==> P
  3478 
  3479     for predicates and
  3480 
  3481       (x_1, ..., x_n) : s z_1 ... z_m ==>
  3482         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3483         ==> ... ==> P
  3484 
  3485     for sets rather than
  3486 
  3487       x : s z_1 ... z_m ==>
  3488         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  3489         ==> ... ==> P
  3490 
  3491     This may require terms in goals to be expanded to n-tuples
  3492     (e.g. using case_tac or simplification with the split_paired_all
  3493     rule) before the above elimination rule is applicable.
  3494 
  3495   - The elimination or case analysis rules for (mutually) inductive
  3496     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  3497     list of rules "p_1_..._p_k.elims" is no longer available.
  3498 
  3499 * New package "function"/"fun" for general recursive functions,
  3500 supporting mutual and nested recursion, definitions in local contexts,
  3501 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  3502 for small examples, and the separate tutorial on the function
  3503 package. The old recdef "package" is still available as before, but
  3504 users are encouraged to use the new package.
  3505 
  3506 * Method "lexicographic_order" automatically synthesizes termination
  3507 relations as lexicographic combinations of size measures. 
  3508 
  3509 * Case-expressions allow arbitrary constructor-patterns (including
  3510 "_") and take their order into account, like in functional
  3511 programming.  Internally, this is translated into nested
  3512 case-expressions; missing cases are added and mapped to the predefined
  3513 constant "undefined". In complicated cases printing may no longer show
  3514 the original input but the internal form. Lambda-abstractions allow
  3515 the same form of pattern matching: "% pat1 => e1 | ..." is an
  3516 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  3517 variable.
  3518 
  3519 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  3520 is an abbreviation for "of_nat :: nat => int". The simplification
  3521 rules for "of_nat" have been changed to work like "int" did
  3522 previously.  Potential INCOMPATIBILITY:
  3523   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  3524   - of_nat_diff and of_nat_mult are no longer default simp rules
  3525 
  3526 * Method "algebra" solves polynomial equations over (semi)rings using
  3527 Groebner bases. The (semi)ring structure is defined by locales and the
  3528 tool setup depends on that generic context. Installing the method for
  3529 a specific type involves instantiating the locale and possibly adding
  3530 declarations for computation on the coefficients.  The method is
  3531 already instantiated for natural numbers and for the axiomatic class
  3532 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  3533 CALCULEMUS 2007 for the general principles underlying this
  3534 architecture of context-aware proof-tools.
  3535 
  3536 * Method "ferrack" implements quantifier elimination over
  3537 special-purpose dense linear orders using locales (analogous to
  3538 "algebra"). The method is already installed for class
  3539 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  3540 rat, etc.
  3541 
  3542 * Former constant "List.op @" now named "List.append".  Use ML
  3543 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  3544 circumvent possible incompatibilities when working on ML level.
  3545 
  3546 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  3547 
  3548 * New function listsum :: 'a list => 'a for arbitrary monoids.
  3549 Special syntax: "SUM x <- xs. f x" (and latex variants)
  3550 
  3551 * New syntax for Haskell-like list comprehension (input only), eg.
  3552 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  3553 
  3554 * The special syntax for function "filter" has changed from [x :
  3555 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  3556 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  3557 
  3558 * [a..b] is now defined for arbitrary linear orders.  It used to be
  3559 defined on nat only, as an abbreviation for [a..<Suc b]
  3560 INCOMPATIBILITY.
  3561 
  3562 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  3563 
  3564 * New functions "sorted" and "sort" in src/HOL/List.thy.
  3565 
  3566 * New lemma collection field_simps (an extension of ring_simps) for
  3567 manipulating (in)equations involving division. Multiplies with all
  3568 denominators that can be proved to be non-zero (in equations) or
  3569 positive/negative (in inequations).
  3570 
  3571 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  3572 have been improved and renamed to ring_simps, group_simps and
  3573 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  3574 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  3575 
  3576 * Theory Library/Commutative_Ring: switched from recdef to function
  3577 package; constants add, mul, pow now curried.  Infix syntax for
  3578 algebraic operations.
  3579 
  3580 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  3581 INCOMPATIBILITY.
  3582 
  3583 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  3584 INCOMPATIBILITY.
  3585 
  3586 * HOL/records: generalised field-update to take a function on the
  3587 field rather than the new value: r(|A := x|) is translated to A_update
  3588 (K x) r The K-combinator that is internally used is called K_record.
  3589 INCOMPATIBILITY: Usage of the plain update functions has to be
  3590 adapted.
  3591  
  3592 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  3593 * x = 0, which are required for a semiring.  Richer structures do not
  3594 inherit from semiring_0 anymore, because this property is a theorem
  3595 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  3596 there is more to prove, but this is mostly trivial.
  3597 
  3598 * Class "recpower" is generalized to arbitrary monoids, not just
  3599 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  3600 commutativity or semiring properties additionally.
  3601 
  3602 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  3603 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  3604 better use 'abbreviation'.
  3605 
  3606 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  3607 
  3608 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  3609 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  3610 significant changes for setting up numeral syntax for types:
  3611   - New constants Numeral.pred and Numeral.succ instead
  3612       of former Numeral.bin_pred and Numeral.bin_succ.
  3613   - Use integer operations instead of bin_add, bin_mult and so on.
  3614   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  3615   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  3616 
  3617 See src/HOL/Integ/IntArith.thy for an example setup.
  3618 
  3619 * Command 'normal_form' computes the normal form of a term that may
  3620 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  3621 produces ``[b, c, a]'' (without proof).  This command is suitable for
  3622 heavy-duty computations because the functions are compiled to ML
  3623 first.  Correspondingly, a method "normalization" is provided.  See
  3624 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  3625 
  3626 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  3627 25 like -->); output depends on the "iff" print_mode, the default is
  3628 "A = B" (with priority 50).
  3629 
  3630 * Relations less (<) and less_eq (<=) are also available on type bool.
  3631 Modified syntax to disallow nesting without explicit parentheses,
  3632 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  3633 INCOMPATIBILITY.
  3634 
  3635 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  3636 
  3637 * Relation composition operator "op O" now has precedence 75 and binds
  3638 stronger than union and intersection. INCOMPATIBILITY.
  3639 
  3640 * The old set interval syntax "{m..n(}" (and relatives) has been
  3641 removed.  Use "{m..<n}" (and relatives) instead.
  3642 
  3643 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  3644 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  3645 ``declare [[simproc del: neq]]''.
  3646 
  3647 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  3648 True/False.
  3649 
  3650 * Theorem Cons_eq_map_conv no longer declared as "simp".
  3651 
  3652 * Theorem setsum_mult renamed to setsum_right_distrib.
  3653 
  3654 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  3655 ``rule'' method.
  3656 
  3657 * Reimplemented methods "sat" and "satx", with several improvements:
  3658 goals no longer need to be stated as "<prems> ==> False", equivalences
  3659 (i.e. "=" on type bool) are handled, variable names of the form
  3660 "lit_<n>" are no longer reserved, significant speedup.
  3661 
  3662 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  3663 zChaff is still supported as well.
  3664 
  3665 * 'inductive' and 'datatype': provide projections of mutual rules,
  3666 bundled as foo_bar.inducts;
  3667 
  3668 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  3669 Library.
  3670 
  3671 * Library: moved theory Accessible_Part to main HOL.
  3672 
  3673 * Library: added theory Coinductive_List of potentially infinite lists
  3674 as greatest fixed-point.
  3675 
  3676 * Library: added theory AssocList which implements (finite) maps as
  3677 association lists.
  3678 
  3679 * Method "evaluation" solves goals (i.e. a boolean expression)
  3680 efficiently by compiling it to ML.  The goal is "proved" (via an
  3681 oracle) if it evaluates to True.
  3682 
  3683 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  3684 also when invoked by the simplifier.  This results in the Simplifier
  3685 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  3686 Configuration option fast_arith_split_limit=0 recovers the old
  3687 behavior.
  3688 
  3689 * Support for hex (0x20) and binary (0b1001) numerals.
  3690 
  3691 * New method: reify eqs (t), where eqs are equations for an
  3692 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  3693 parameter, computes a term s::'b and a list xs::'a list and proves the
  3694 theorem I xs s = t. This is also known as reification or quoting. The
  3695 resulting theorem is applied to the subgoal to substitute t with I xs
  3696 s.  If t is omitted, the subgoal itself is reified.
  3697 
  3698 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  3699 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  3700 where f is supposed to be a computable function (in the sense of code
  3701 generattion). The method uses reify to compute s and xs as above then
  3702 applies corr_thm and uses normalization by evaluation to "prove" f s =
  3703 r and finally gets the theorem t = r, which is again applied to the
  3704 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  3705 
  3706 * Reflection: Automatic reification now handels binding, an example is
  3707 available in src/HOL/ex/ReflectionEx.thy
  3708 
  3709 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  3710 command 'statespace' that is similar to 'record', but introduces an
  3711 abstract specification based on the locale infrastructure instead of
  3712 HOL types.  This leads to extra flexibility in composing state spaces,
  3713 in particular multiple inheritance and renaming of components.
  3714 
  3715 
  3716 *** HOL-Complex ***
  3717 
  3718 * Hyperreal: Functions root and sqrt are now defined on negative real
  3719 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  3720 Nonnegativity side conditions have been removed from many lemmas, so
  3721 that more subgoals may now be solved by simplification; potential
  3722 INCOMPATIBILITY.
  3723 
  3724 * Real: new type classes formalize real normed vector spaces and
  3725 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  3726 and norm :: 'a => real.
  3727 
  3728 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  3729 reals into other types. The overloaded constant Reals :: 'a set is now
  3730 defined as range of_real; potential INCOMPATIBILITY.
  3731 
  3732 * Real: proper support for ML code generation, including 'quickcheck'.
  3733 Reals are implemented as arbitrary precision rationals.
  3734 
  3735 * Hyperreal: Several constants that previously worked only for the
  3736 reals have been generalized, so they now work over arbitrary vector
  3737 spaces. Type annotations may need to be added in some cases; potential
  3738 INCOMPATIBILITY.
  3739 
  3740   Infinitesimal  :: ('a::real_normed_vector) star set
  3741   HFinite        :: ('a::real_normed_vector) star set
  3742   HInfinite      :: ('a::real_normed_vector) star set
  3743   approx         :: ('a::real_normed_vector) star => 'a star => bool
  3744   monad          :: ('a::real_normed_vector) star => 'a star set
  3745   galaxy         :: ('a::real_normed_vector) star => 'a star set
  3746   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  3747   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  3748   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  3749   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  3750   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  3751   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  3752   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  3753   sgn            :: 'a::real_normed_vector => 'a
  3754   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  3755 
  3756 * Complex: Some complex-specific constants are now abbreviations for
  3757 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  3758 hnorm.  Other constants have been entirely removed in favor of the
  3759 polymorphic versions (INCOMPATIBILITY):
  3760 
  3761   approx        <-- capprox
  3762   HFinite       <-- CFinite
  3763   HInfinite     <-- CInfinite
  3764   Infinitesimal <-- CInfinitesimal
  3765   monad         <-- cmonad
  3766   galaxy        <-- cgalaxy
  3767   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  3768   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  3769   (ns)deriv     <-- (ns)cderiv
  3770 
  3771 
  3772 *** HOL-Algebra ***
  3773 
  3774 * Formalisation of ideals and the quotient construction over rings.
  3775 
  3776 * Order and lattice theory no longer based on records.
  3777 INCOMPATIBILITY.
  3778 
  3779 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  3780 greatest_closed.  INCOMPATIBILITY.
  3781 
  3782 * Method algebra is now set up via an attribute.  For examples see
  3783 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  3784 of algebraic structures.
  3785 
  3786 * Renamed theory CRing to Ring.
  3787 
  3788 
  3789 *** HOL-Nominal ***
  3790 
  3791 * Substantial, yet incomplete support for nominal datatypes (binding
  3792 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  3793 src/HOL/Nominal/Examples.  Prospective users should consult
  3794 http://isabelle.in.tum.de/nominal/
  3795 
  3796 
  3797 *** ML ***
  3798 
  3799 * ML basics: just one true type int, which coincides with IntInf.int
  3800 (even on SML/NJ).
  3801 
  3802 * ML within Isar: antiquotations allow to embed statically-checked
  3803 formal entities in the source, referring to the context available at
  3804 compile-time.  For example:
  3805 
  3806 ML {* @{sort "{zero,one}"} *}
  3807 ML {* @{typ "'a => 'b"} *}
  3808 ML {* @{term "%x. x"} *}
  3809 ML {* @{prop "x == y"} *}
  3810 ML {* @{ctyp "'a => 'b"} *}
  3811 ML {* @{cterm "%x. x"} *}
  3812 ML {* @{cprop "x == y"} *}
  3813 ML {* @{thm asm_rl} *}
  3814 ML {* @{thms asm_rl} *}
  3815 ML {* @{type_name c} *}
  3816 ML {* @{type_syntax c} *}
  3817 ML {* @{const_name c} *}
  3818 ML {* @{const_syntax c} *}
  3819 ML {* @{context} *}
  3820 ML {* @{theory} *}
  3821 ML {* @{theory Pure} *}
  3822 ML {* @{theory_ref} *}
  3823 ML {* @{theory_ref Pure} *}
  3824 ML {* @{simpset} *}
  3825 ML {* @{claset} *}
  3826 ML {* @{clasimpset} *}
  3827 
  3828 The same works for sources being ``used'' within an Isar context.
  3829 
  3830 * ML in Isar: improved error reporting; extra verbosity with
  3831 ML_Context.trace enabled.
  3832 
  3833 * Pure/General/table.ML: the join operations now works via exceptions
  3834 DUP/SAME instead of type option. This is simpler in simple cases, and
  3835 admits slightly more efficient complex applications.
  3836 
  3837 * Pure: 'advanced' translation functions (parse_translation etc.) now
  3838 use Context.generic instead of just theory.
  3839 
  3840 * Pure: datatype Context.generic joins theory/Proof.context and
  3841 provides some facilities for code that works in either kind of
  3842 context, notably GenericDataFun for uniform theory and proof data.
  3843 
  3844 * Pure: simplified internal attribute type, which is now always
  3845 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  3846 local (Proof.context) attributes have been discontinued, while
  3847 minimizing code duplication. Thm.rule_attribute and
  3848 Thm.declaration_attribute build canonical attributes; see also structure
  3849 Context for further operations on Context.generic, notably
  3850 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  3851 declarations and definitions.
  3852 
  3853 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  3854 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  3855 init only required for impure data. INCOMPATIBILITY: empty really need
  3856 to be empty (no dependencies on theory content!)
  3857 
  3858 * Pure/kernel: consts certification ignores sort constraints given in
  3859 signature declarations. (This information is not relevant to the
  3860 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  3861 potential INCOMPATIBILITY.
  3862 
  3863 * Pure: axiomatic type classes are now purely definitional, with
  3864 explicit proofs of class axioms and super class relations performed
  3865 internally. See Pure/axclass.ML for the main internal interfaces --
  3866 notably AxClass.define_class supercedes AxClass.add_axclass, and
  3867 AxClass.axiomatize_class/classrel/arity supersede
  3868 Sign.add_classes/classrel/arities.
  3869 
  3870 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  3871 global/local versions on theory vs. Proof.context have been
  3872 discontinued; Attrib.syntax and Method.syntax have been adapted
  3873 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  3874 attributes, methods, etc.
  3875 
  3876 * Pure: several functions of signature "... -> theory -> theory * ..."
  3877 have been reoriented to "... -> theory -> ... * theory" in order to
  3878 allow natural usage in combination with the ||>, ||>>, |-> and
  3879 fold_map combinators.
  3880 
  3881 * Pure: official theorem names (closed derivations) and additional
  3882 comments (tags) are now strictly separate.  Name hints -- which are
  3883 maintained as tags -- may be attached any time without affecting the
  3884 derivation.
  3885 
  3886 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  3887 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  3888 achieve the old behaviour.
  3889 
  3890 * Pure: the "Goal" constant is now called "prop", supporting a
  3891 slightly more general idea of ``protecting'' meta-level rule
  3892 statements.
  3893 
  3894 * Pure: Logic.(un)varify only works in a global context, which is now
  3895 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  3896 Logic.legacy_(un)varify as temporary workaround.
  3897 
  3898 * Pure: structure Name provides scalable operations for generating
  3899 internal variable names, notably Name.variants etc.  This replaces
  3900 some popular functions from term.ML:
  3901 
  3902   Term.variant		->  Name.variant
  3903   Term.variantlist	->  Name.variant_list
  3904   Term.invent_names	->  Name.invent_list
  3905 
  3906 Note that low-level renaming rarely occurs in new code -- operations
  3907 from structure Variable are used instead (see below).
  3908 
  3909 * Pure: structure Variable provides fundamental operations for proper
  3910 treatment of fixed/schematic variables in a context.  For example,
  3911 Variable.import introduces fixes for schematics of given facts and
  3912 Variable.export reverses the effect (up to renaming) -- this replaces
  3913 various freeze_thaw operations.
  3914 
  3915 * Pure: structure Goal provides simple interfaces for
  3916 init/conclude/finish and tactical prove operations (replacing former
  3917 Tactic.prove).  Goal.prove is the canonical way to prove results
  3918 within a given context; Goal.prove_global is a degraded version for
  3919 theory level goals, including a global Drule.standard.  Note that
  3920 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  3921 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  3922 in a locale context).
  3923 
  3924 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  3925 and type checking (Syntax.check_term etc.), with common combinations
  3926 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  3927 which are considered legacy and await removal.
  3928 
  3929 * Pure/Syntax: generic interfaces for type unchecking
  3930 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  3931 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  3932 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  3933 available for convenience, but refer to the very same operations using
  3934 a mere theory instead of a full context.
  3935 
  3936 * Isar: simplified treatment of user-level errors, using exception
  3937 ERROR of string uniformly.  Function error now merely raises ERROR,
  3938 without any side effect on output channels.  The Isar toplevel takes
  3939 care of proper display of ERROR exceptions.  ML code may use plain
  3940 handle/can/try; cat_error may be used to concatenate errors like this:
  3941 
  3942   ... handle ERROR msg => cat_error msg "..."
  3943 
  3944 Toplevel ML code (run directly or through the Isar toplevel) may be
  3945 embedded into the Isar toplevel with exception display/debug like
  3946 this:
  3947 
  3948   Isar.toplevel (fn () => ...)
  3949 
  3950 INCOMPATIBILITY, removed special transform_error facilities, removed
  3951 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  3952 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  3953 -- use plain ERROR instead.
  3954 
  3955 * Isar: theory setup now has type (theory -> theory), instead of a
  3956 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  3957 
  3958 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  3959 ProofContext.debug/verbose flags.
  3960 
  3961 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  3962 theory before entering a proof state.  Transactions now always see a
  3963 quasi-functional intermediate checkpoint, both in interactive and
  3964 batch mode.
  3965 
  3966 * Isar: simplified interfaces for outer syntax.  Renamed
  3967 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  3968 OuterSyntax.add_parsers -- this functionality is now included in
  3969 OuterSyntax.command etc.  INCOMPATIBILITY.
  3970 
  3971 * Simplifier: the simpset of a running simplification process now
  3972 contains a proof context (cf. Simplifier.the_context), which is the
  3973 very context that the initial simpset has been retrieved from (by
  3974 simpset_of/local_simpset_of).  Consequently, all plug-in components
  3975 (solver, looper etc.) may depend on arbitrary proof data.
  3976 
  3977 * Simplifier.inherit_context inherits the proof context (plus the
  3978 local bounds) of the current simplification process; any simproc
  3979 etc. that calls the Simplifier recursively should do this!  Removed
  3980 former Simplifier.inherit_bounds, which is already included here --
  3981 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  3982 specify an explicit context using Simplifier.context/theory_context.
  3983 
  3984 * Simplifier/Classical Reasoner: more abstract interfaces
  3985 change_simpset/claset for modifying the simpset/claset reference of a
  3986 theory; raw versions simpset/claset_ref etc. have been discontinued --
  3987 INCOMPATIBILITY.
  3988 
  3989 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  3990 "Trueprop" etc.
  3991 
  3992 
  3993 *** System ***
  3994 
  3995 * settings: the default heap location within ISABELLE_HOME_USER now
  3996 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  3997 Isabelle installations.
  3998 
  3999 * isabelle-process: option -S (secure mode) disables some critical
  4000 operations, notably runtime compilation and evaluation of ML source
  4001 code.
  4002 
  4003 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4004 
  4005 * Support for parallel execution, using native multicore support of
  4006 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4007 independent theories, according to the given theory header
  4008 specifications. The maximum number of worker threads is specified via
  4009 usedir option -M or the "max-threads" setting in Proof General. A
  4010 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4011 to 6 on a 8-core machine.  User-code needs to observe certain
  4012 guidelines for thread-safe programming, see appendix A in the Isar
  4013 Implementation manual.
  4014 
  4015 
  4016 
  4017 New in Isabelle2005 (October 2005)
  4018 ----------------------------------
  4019 
  4020 *** General ***
  4021 
  4022 * Theory headers: the new header syntax for Isar theories is
  4023 
  4024   theory <name>
  4025   imports <theory1> ... <theoryN>
  4026   uses <file1> ... <fileM>
  4027   begin
  4028 
  4029 where the 'uses' part is optional.  The previous syntax
  4030 
  4031   theory <name> = <theory1> + ... + <theoryN>:
  4032 
  4033 will disappear in the next release.  Use isatool fixheaders to convert
  4034 existing theory files.  Note that there is no change in ancient
  4035 non-Isar theories now, but these will disappear soon.
  4036 
  4037 * Theory loader: parent theories can now also be referred to via
  4038 relative and absolute paths.
  4039 
  4040 * Command 'find_theorems' searches for a list of criteria instead of a
  4041 list of constants. Known criteria are: intro, elim, dest, name:string,
  4042 simp:term, and any term. Criteria can be preceded by '-' to select
  4043 theorems that do not match. Intro, elim, dest select theorems that
  4044 match the current goal, name:s selects theorems whose fully qualified
  4045 name contain s, and simp:term selects all simplification rules whose
  4046 lhs match term.  Any other term is interpreted as pattern and selects
  4047 all theorems matching the pattern. Available in ProofGeneral under
  4048 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4049 
  4050   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4051 
  4052 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4053 matching the current goal as introduction rule and not having "HOL."
  4054 in their name (i.e. not being defined in theory HOL).
  4055 
  4056 * Command 'thms_containing' has been discontinued in favour of
  4057 'find_theorems'; INCOMPATIBILITY.
  4058 
  4059 * Communication with Proof General is now 8bit clean, which means that
  4060 Unicode text in UTF-8 encoding may be used within theory texts (both
  4061 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4062 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4063 
  4064   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4065   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4066 
  4067 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4068 Classical Reasoner.  Typical big applications run around 2 times
  4069 faster.
  4070 
  4071 
  4072 *** Document preparation ***
  4073 
  4074 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4075 of raw sources.  Only those symbols that do not require additional
  4076 LaTeX packages (depending on comments in isabellesym.sty) are
  4077 displayed properly, everything else is left verbatim.  isatool display
  4078 and isatool print are used as front ends (these are subject to the
  4079 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4080 
  4081 * Command tags control specific markup of certain regions of text,
  4082 notably folding and hiding.  Predefined tags include "theory" (for
  4083 theory begin and end), "proof" for proof commands, and "ML" for
  4084 commands involving ML code; the additional tags "visible" and
  4085 "invisible" are unused by default.  Users may give explicit tag
  4086 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4087 interpretation of tags is determined by the LaTeX job during document
  4088 preparation: see option -V of isatool usedir, or options -n and -t of
  4089 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4090 \isadroptag.
  4091 
  4092 Several document versions may be produced at the same time via isatool
  4093 usedir (the generated index.html will link all of them).  Typical
  4094 specifications include ''-V document=theory,proof,ML'' to present
  4095 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4096 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4097 these parts without any formal replacement text.  The Isabelle site
  4098 default settings produce ''document'' and ''outline'' versions as
  4099 specified above.
  4100 
  4101 * Several new antiquotations:
  4102 
  4103   @{term_type term} prints a term with its type annotated;
  4104 
  4105   @{typeof term} prints the type of a term;
  4106 
  4107   @{const const} is the same as @{term const}, but checks that the
  4108   argument is a known logical constant;
  4109 
  4110   @{term_style style term} and @{thm_style style thm} print a term or
  4111   theorem applying a "style" to it
  4112 
  4113   @{ML text}
  4114 
  4115 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4116 definitions, equations, inequations etc., 'concl' printing only the
  4117 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4118 to print the specified premise.  TermStyle.add_style provides an ML
  4119 interface for introducing further styles.  See also the "LaTeX Sugar"
  4120 document practical applications.  The ML antiquotation prints
  4121 type-checked ML expressions verbatim.
  4122 
  4123 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4124 and 'text' support optional locale specification '(in loc)', which
  4125 specifies the default context for interpreting antiquotations.  For
  4126 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4127 
  4128 * Option 'locale=NAME' of antiquotations specifies an alternative
  4129 context interpreting the subsequent argument.  For example: @{thm
  4130 [locale=lattice] inf_assoc}.
  4131 
  4132 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4133 a proof context.
  4134 
  4135 * Proper output of antiquotations for theory commands involving a
  4136 proof context (such as 'locale' or 'theorem (in loc) ...').
  4137 
  4138 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4139 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4140 
  4141 * isatool usedir: new option -C (default true) controls whether option
  4142 -D should include a copy of the original document directory; -C false
  4143 prevents unwanted effects such as copying of administrative CVS data.
  4144 
  4145 
  4146 *** Pure ***
  4147 
  4148 * Considerably improved version of 'constdefs' command.  Now performs
  4149 automatic type-inference of declared constants; additional support for
  4150 local structure declarations (cf. locales and HOL records), see also
  4151 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4152 sequential dependencies of definitions within a single 'constdefs'
  4153 section; moreover, the declared name needs to be an identifier.  If
  4154 all fails, consider to fall back on 'consts' and 'defs' separately.
  4155 
  4156 * Improved indexed syntax and implicit structures.  First of all,
  4157 indexed syntax provides a notational device for subscripted
  4158 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4159 expressions.  Secondly, in a local context with structure
  4160 declarations, number indexes \<^sub>n or the empty index (default
  4161 number 1) refer to a certain fixed variable implicitly; option
  4162 show_structs controls printing of implicit structures.  Typical
  4163 applications of these concepts involve record types and locales.
  4164 
  4165 * New command 'no_syntax' removes grammar declarations (and
  4166 translations) resulting from the given syntax specification, which is
  4167 interpreted in the same manner as for the 'syntax' command.
  4168 
  4169 * 'Advanced' translation functions (parse_translation etc.) may depend
  4170 on the signature of the theory context being presently used for
  4171 parsing/printing, see also isar-ref manual.
  4172 
  4173 * Improved 'oracle' command provides a type-safe interface to turn an
  4174 ML expression of type theory -> T -> term into a primitive rule of
  4175 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4176 is already included here); see also FOL/ex/IffExample.thy;
  4177 INCOMPATIBILITY.
  4178 
  4179 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4180 before); "cI" is no longer bound, use "c.intro" instead.
  4181 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4182 axclasses vs. locales.
  4183 
  4184 * Improved internal renaming of symbolic identifiers -- attach primes
  4185 instead of base 26 numbers.
  4186 
  4187 * New flag show_question_marks controls printing of leading question
  4188 marks in schematic variable names.
  4189 
  4190 * In schematic variable names, *any* symbol following \<^isub> or
  4191 \<^isup> is now treated as part of the base name.  For example, the
  4192 following works without printing of awkward ".0" indexes:
  4193 
  4194   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4195     by simp
  4196 
  4197 * Inner syntax includes (*(*nested*) comments*).
  4198 
  4199 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4200 annotations as "(00...)".
  4201 
  4202 * Clear separation of logical types and nonterminals, where the latter
  4203 may only occur in 'syntax' specifications or type abbreviations.
  4204 Before that distinction was only partially implemented via type class
  4205 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4206 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4207 exotic syntax specifications may require further adaption
  4208 (e.g. Cube/Cube.thy).
  4209 
  4210 * Removed obsolete type class "logic", use the top sort {} instead.
  4211 Note that non-logical types should be declared as 'nonterminals'
  4212 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4213 specifications.
  4214 
  4215 * Attributes 'induct' and 'cases': type or set names may now be
  4216 locally fixed variables as well.
  4217 
  4218 * Simplifier: can now control the depth to which conditional rewriting
  4219 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4220 Limit.
  4221 
  4222 * Simplifier: simplification procedures may now take the current
  4223 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4224 interface), which is very useful for calling the Simplifier
  4225 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4226 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4227 low-level mk_simproc no longer applies Logic.varify internally, to
  4228 allow for use in a context of fixed variables.
  4229 
  4230 * thin_tac now works even if the assumption being deleted contains !!
  4231 or ==>.  More generally, erule now works even if the major premise of
  4232 the elimination rule contains !! or ==>.
  4233 
  4234 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4235 
  4236 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4237 from Pure, which contains all common declarations already.  Both
  4238 theories are defined via plain Isabelle/Isar .thy files.
  4239 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4240 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4241 use isatool fixcpure to adapt your theory and ML sources.
  4242 
  4243 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4244 selections of theorems in named facts via index ranges.
  4245 
  4246 * 'print_theorems': in theory mode, really print the difference
  4247 wrt. the last state (works for interactive theory development only),
  4248 in proof mode print all local facts (cf. 'print_facts');
  4249 
  4250 * 'hide': option '(open)' hides only base names.
  4251 
  4252 * More efficient treatment of intermediate checkpoints in interactive
  4253 theory development.
  4254 
  4255 * Code generator is now invoked via code_module (incremental code
  4256 generation) and code_library (modular code generation, ML structures
  4257 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4258 must be quoted when used as identifiers.
  4259 
  4260 * New 'value' command for reading, evaluating and printing terms using
  4261 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4262 quoted when used as identifier.
  4263 
  4264 
  4265 *** Locales ***
  4266 
  4267 * New commands for the interpretation of locale expressions in
  4268 theories (1), locales (2) and proof contexts (3).  These generate
  4269 proof obligations from the expression specification.  After the
  4270 obligations have been discharged, theorems of the expression are added
  4271 to the theory, target locale or proof context.  The synopsis of the
  4272 commands is a follows:
  4273 
  4274   (1) interpretation expr inst
  4275   (2) interpretation target < expr
  4276   (3) interpret expr inst
  4277 
  4278 Interpretation in theories and proof contexts require a parameter
  4279 instantiation of terms from the current context.  This is applied to
  4280 specifications and theorems of the interpreted expression.
  4281 Interpretation in locales only permits parameter renaming through the
  4282 locale expression.  Interpretation is smart in that interpretations
  4283 that are active already do not occur in proof obligations, neither are
  4284 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4285 inspect active interpretations of a particular locale.  For details,
  4286 see the Isar Reference manual.  Examples can be found in
  4287 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4288 
  4289 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4290 'interpret' instead.
  4291 
  4292 * New context element 'constrains' for adding type constraints to
  4293 parameters.
  4294 
  4295 * Context expressions: renaming of parameters with syntax
  4296 redeclaration.
  4297 
  4298 * Locale declaration: 'includes' disallowed.
  4299 
  4300 * Proper static binding of attribute syntax -- i.e. types / terms /
  4301 facts mentioned as arguments are always those of the locale definition
  4302 context, independently of the context of later invocations.  Moreover,
  4303 locale operations (renaming and type / term instantiation) are applied
  4304 to attribute arguments as expected.
  4305 
  4306 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4307 actual attributes; rare situations may require Attrib.attribute to
  4308 embed those attributes into Attrib.src that lack concrete syntax.
  4309 Attribute implementations need to cooperate properly with the static
  4310 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4311 Attrib.XXX_thm etc. already do the right thing without further
  4312 intervention.  Only unusual applications -- such as "where" or "of"
  4313 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4314 on the context and the facts involved -- may have to assign parsed
  4315 values to argument tokens explicitly.
  4316 
  4317 * Changed parameter management in theorem generation for long goal
  4318 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4319 theorem statement in rare situations.
  4320 
  4321 * Locale inspection command 'print_locale' omits notes elements.  Use
  4322 'print_locale!' to have them included in the output.
  4323 
  4324 
  4325 *** Provers ***
  4326 
  4327 * Provers/hypsubst.ML: improved version of the subst method, for
  4328 single-step rewriting: it now works in bound variable contexts. New is
  4329 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4330 rewrite a different subterm than the original subst method, which is
  4331 still available as 'simplesubst'.
  4332 
  4333 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4334 and quasi orders.
  4335 
  4336 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4337 reflexive-transitive closure of relations.
  4338 
  4339 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4340 limit (previously hard-coded with a value of 20) user-definable.
  4341 
  4342 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4343 is peformed already.  Object-logics merely need to finish their
  4344 initial simpset configuration as before.  INCOMPATIBILITY.
  4345 
  4346 
  4347 *** HOL ***
  4348 
  4349 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4350 
  4351   syntax (epsilon)
  4352     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4353 
  4354 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4355 and x-symbol; use option '-m epsilon' to get it actually printed.
  4356 Moreover, the mathematically important symbolic identifier \<epsilon>
  4357 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4358 
  4359 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  4360 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  4361 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  4362 support corresponding Isar calculations.
  4363 
  4364 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  4365 instead of ":".
  4366 
  4367 * theory SetInterval: changed the syntax for open intervals:
  4368 
  4369   Old       New
  4370   {..n(}    {..<n}
  4371   {)n..}    {n<..}
  4372   {m..n(}   {m..<n}
  4373   {)m..n}   {m<..n}
  4374   {)m..n(}  {m<..<n}
  4375 
  4376 The old syntax is still supported but will disappear in the next
  4377 release.  For conversion use the following Emacs search and replace
  4378 patterns (these are not perfect but work quite well):
  4379 
  4380   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  4381   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  4382 
  4383 * Theory Commutative_Ring (in Library): method comm_ring for proving
  4384 equalities in commutative rings; method 'algebra' provides a generic
  4385 interface.
  4386 
  4387 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  4388 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  4389 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  4390 be a tuple pattern.
  4391 
  4392 Some new syntax forms are available:
  4393 
  4394   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  4395   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  4396   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  4397   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  4398 
  4399 The latter form "\<Sum>x < k. e" used to be based on a separate
  4400 function "Summation", which has been discontinued.
  4401 
  4402 * theory Finite_Set: in structured induction proofs, the insert case
  4403 is now 'case (insert x F)' instead of the old counterintuitive 'case
  4404 (insert F x)'.
  4405 
  4406 * The 'refute' command has been extended to support a much larger
  4407 fragment of HOL, including axiomatic type classes, constdefs and
  4408 typedefs, inductive datatypes and recursion.
  4409 
  4410 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  4411 Requires zChaff with proof generation to be installed.  See
  4412 HOL/ex/SAT_Examples.thy for examples.
  4413 
  4414 * Datatype induction via method 'induct' now preserves the name of the
  4415 induction variable. For example, when proving P(xs::'a list) by
  4416 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  4417 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  4418 in unstructured proof scripts.
  4419 
  4420 * Reworked implementation of records.  Improved scalability for
  4421 records with many fields, avoiding performance problems for type
  4422 inference. Records are no longer composed of nested field types, but
  4423 of nested extension types. Therefore the record type only grows linear
  4424 in the number of extensions and not in the number of fields.  The
  4425 top-level (users) view on records is preserved.  Potential
  4426 INCOMPATIBILITY only in strange cases, where the theory depends on the
  4427 old record representation. The type generated for a record is called
  4428 <record_name>_ext_type.
  4429 
  4430 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  4431 proofs triggered by a record definition or a simproc (if
  4432 quick_and_dirty is enabled).  Definitions of large records can take
  4433 quite long.
  4434 
  4435 New simproc record_upd_simproc for simplification of multiple record
  4436 updates enabled by default.  Moreover, trivial updates are also
  4437 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  4438 occasionally, since simplification is more powerful by default.
  4439 
  4440 * typedef: proper support for polymorphic sets, which contain extra
  4441 type-variables in the term.
  4442 
  4443 * Simplifier: automatically reasons about transitivity chains
  4444 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  4445 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  4446 old proofs break occasionally as simplification may now solve more
  4447 goals than previously.
  4448 
  4449 * Simplifier: converts x <= y into x = y if assumption y <= x is
  4450 present.  Works for all partial orders (class "order"), in particular
  4451 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  4452 just like y <= x.
  4453 
  4454 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  4455 bound variable or a constant then the let is unfolded.  Otherwise
  4456 first a is simplified to b, and then f b is simplified to g. If
  4457 possible we abstract b from g arriving at "let x = b in h x",
  4458 otherwise we unfold the let and arrive at g.  The simproc can be
  4459 enabled/disabled by the reference use_let_simproc.  Potential
  4460 INCOMPATIBILITY since simplification is more powerful by default.
  4461 
  4462 * Classical reasoning: the meson method now accepts theorems as arguments.
  4463 
  4464 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  4465 jobs to provide advice on the provability of subgoals.
  4466 
  4467 * Theory OrderedGroup and Ring_and_Field: various additions and
  4468 improvements to faciliate calculations involving equalities and
  4469 inequalities.
  4470 
  4471 The following theorems have been eliminated or modified
  4472 (INCOMPATIBILITY):
  4473 
  4474   abs_eq             now named abs_of_nonneg
  4475   abs_of_ge_0        now named abs_of_nonneg
  4476   abs_minus_eq       now named abs_of_nonpos
  4477   imp_abs_id         now named abs_of_nonneg
  4478   imp_abs_neg_id     now named abs_of_nonpos
  4479   mult_pos           now named mult_pos_pos
  4480   mult_pos_le        now named mult_nonneg_nonneg
  4481   mult_pos_neg_le    now named mult_nonneg_nonpos
  4482   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  4483   mult_neg           now named mult_neg_neg
  4484   mult_neg_le        now named mult_nonpos_nonpos
  4485 
  4486 * The following lemmas in Ring_and_Field have been added to the simplifier:
  4487      
  4488      zero_le_square
  4489      not_square_less_zero 
  4490 
  4491   The following lemmas have been deleted from Real/RealPow:
  4492   
  4493      realpow_zero_zero
  4494      realpow_two
  4495      realpow_less
  4496      zero_le_power
  4497      realpow_two_le
  4498      abs_realpow_two
  4499      realpow_two_abs     
  4500 
  4501 * Theory Parity: added rules for simplifying exponents.
  4502 
  4503 * Theory List:
  4504 
  4505 The following theorems have been eliminated or modified
  4506 (INCOMPATIBILITY):
  4507 
  4508   list_all_Nil       now named list_all.simps(1)
  4509   list_all_Cons      now named list_all.simps(2)
  4510   list_all_conv      now named list_all_iff
  4511   set_mem_eq         now named mem_iff
  4512 
  4513 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  4514 asymptotic "big O" calculations.  See the notes in BigO.thy.
  4515 
  4516 
  4517 *** HOL-Complex ***
  4518 
  4519 * Theory RealDef: better support for embedding natural numbers and
  4520 integers in the reals.
  4521 
  4522 The following theorems have been eliminated or modified
  4523 (INCOMPATIBILITY):
  4524 
  4525   exp_ge_add_one_self  now requires no hypotheses
  4526   real_of_int_add      reversed direction of equality (use [symmetric])
  4527   real_of_int_minus    reversed direction of equality (use [symmetric])
  4528   real_of_int_diff     reversed direction of equality (use [symmetric])
  4529   real_of_int_mult     reversed direction of equality (use [symmetric])
  4530 
  4531 * Theory RComplete: expanded support for floor and ceiling functions.
  4532 
  4533 * Theory Ln is new, with properties of the natural logarithm
  4534 
  4535 * Hyperreal: There is a new type constructor "star" for making
  4536 nonstandard types.  The old type names are now type synonyms:
  4537 
  4538   hypreal = real star
  4539   hypnat = nat star
  4540   hcomplex = complex star
  4541 
  4542 * Hyperreal: Many groups of similarly-defined constants have been
  4543 replaced by polymorphic versions (INCOMPATIBILITY):
  4544 
  4545   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  4546 
  4547   starset      <-- starsetNat, starsetC
  4548   *s*          <-- *sNat*, *sc*
  4549   starset_n    <-- starsetNat_n, starsetC_n
  4550   *sn*         <-- *sNatn*, *scn*
  4551   InternalSets <-- InternalNatSets, InternalCSets
  4552 
  4553   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  4554   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  4555   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  4556   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  4557   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  4558 
  4559 * Hyperreal: Many type-specific theorems have been removed in favor of
  4560 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  4561 
  4562   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  4563   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  4564   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  4565   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  4566   right_minus <-- hypreal_add_minus
  4567   left_minus <-- {hypreal,hcomplex}_add_minus_left
  4568   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  4569   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  4570   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  4571   mult_1_right <-- hcomplex_mult_one_right
  4572   mult_zero_left <-- hcomplex_mult_zero_left
  4573   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  4574   right_distrib <-- hypnat_add_mult_distrib2
  4575   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  4576   right_inverse <-- hypreal_mult_inverse
  4577   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  4578   order_refl <-- {hypreal,hypnat}_le_refl
  4579   order_trans <-- {hypreal,hypnat}_le_trans
  4580   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  4581   order_less_le <-- {hypreal,hypnat}_less_le
  4582   linorder_linear <-- {hypreal,hypnat}_le_linear
  4583   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  4584   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  4585   add_nonneg_nonneg <-- hypreal_le_add_order
  4586 
  4587 * Hyperreal: Separate theorems having to do with type-specific
  4588 versions of constants have been merged into theorems that apply to the
  4589 new polymorphic constants (INCOMPATIBILITY):
  4590 
  4591   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  4592   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  4593   STAR_Un <-- {STAR,NatStar,STARC}_Un
  4594   STAR_Int <-- {STAR,NatStar,STARC}_Int
  4595   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  4596   STAR_subset <-- {STAR,NatStar,STARC}_subset
  4597   STAR_mem <-- {STAR,NatStar,STARC}_mem
  4598   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  4599   STAR_diff <-- {STAR,STARC}_diff
  4600   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  4601     STARC_hcomplex_of_complex}_image_subset
  4602   starset_n_Un <-- starset{Nat,C}_n_Un
  4603   starset_n_Int <-- starset{Nat,C}_n_Int
  4604   starset_n_Compl <-- starset{Nat,C}_n_Compl
  4605   starset_n_diff <-- starset{Nat,C}_n_diff
  4606   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  4607   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  4608   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  4609   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  4610   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  4611   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  4612   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  4613   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  4614   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  4615   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  4616   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  4617   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  4618   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  4619   starfun_diff <-- starfun{C,RC,CR}_diff
  4620   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  4621   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  4622   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  4623   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  4624   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  4625   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  4626   starfun_Id <-- starfunC_Id
  4627   starfun_approx <-- starfun{Nat,CR}_approx
  4628   starfun_capprox <-- starfun{C,RC}_capprox
  4629   starfun_abs <-- starfunNat_rabs
  4630   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  4631   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  4632   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  4633   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  4634   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  4635   starfun_add_approx <-- starfunCR_add_approx
  4636   starfun_inverse_inverse <-- starfunC_inverse_inverse
  4637   starfun_divide <-- starfun{C,CR,RC}_divide
  4638   starfun_n <-- starfun{Nat,C}_n
  4639   starfun_n_mult <-- starfun{Nat,C}_n_mult
  4640   starfun_n_add <-- starfun{Nat,C}_n_add
  4641   starfun_n_add_minus <-- starfunNat_n_add_minus
  4642   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  4643   starfun_n_minus <-- starfun{Nat,C}_n_minus
  4644   starfun_n_eq <-- starfun{Nat,C}_n_eq
  4645 
  4646   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  4647   star_n_minus <-- {hypreal,hcomplex}_minus
  4648   star_n_diff <-- {hypreal,hcomplex}_diff
  4649   star_n_mult <-- {hypreal,hcomplex}_mult
  4650   star_n_inverse <-- {hypreal,hcomplex}_inverse
  4651   star_n_le <-- {hypreal,hypnat}_le
  4652   star_n_less <-- {hypreal,hypnat}_less
  4653   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  4654   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  4655   star_n_abs <-- hypreal_hrabs
  4656   star_n_divide <-- hcomplex_divide
  4657 
  4658   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  4659   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  4660   star_of_diff <-- hypreal_of_real_diff
  4661   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  4662   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  4663   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  4664   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  4665   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  4666   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  4667   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  4668   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  4669   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  4670   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  4671   star_of_number_of <-- {hypreal,hcomplex}_number_of
  4672   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  4673   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  4674   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  4675   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  4676   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  4677   star_of_power <-- hypreal_of_real_power
  4678   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  4679 
  4680 * Hyperreal: new method "transfer" that implements the transfer
  4681 principle of nonstandard analysis. With a subgoal that mentions
  4682 nonstandard types like "'a star", the command "apply transfer"
  4683 replaces it with an equivalent one that mentions only standard types.
  4684 To be successful, all free variables must have standard types; non-
  4685 standard variables must have explicit universal quantifiers.
  4686 
  4687 * Hyperreal: A theory of Taylor series.
  4688 
  4689 
  4690 *** HOLCF ***
  4691 
  4692 * Discontinued special version of 'constdefs' (which used to support
  4693 continuous functions) in favor of the general Pure one with full
  4694 type-inference.
  4695 
  4696 * New simplification procedure for solving continuity conditions; it
  4697 is much faster on terms with many nested lambda abstractions (cubic
  4698 instead of exponential time).
  4699 
  4700 * New syntax for domain package: selector names are now optional.
  4701 Parentheses should be omitted unless argument is lazy, for example:
  4702 
  4703   domain 'a stream = cons "'a" (lazy "'a stream")
  4704 
  4705 * New command 'fixrec' for defining recursive functions with pattern
  4706 matching; defining multiple functions with mutual recursion is also
  4707 supported.  Patterns may include the constants cpair, spair, up, sinl,
  4708 sinr, or any data constructor defined by the domain package. The given
  4709 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  4710 syntax and examples.
  4711 
  4712 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  4713 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  4714 but the proof obligation additionally includes an admissibility
  4715 requirement. The packages generate instances of class cpo or pcpo,
  4716 with continuity and strictness theorems for Rep and Abs.
  4717 
  4718 * HOLCF: Many theorems have been renamed according to a more standard naming
  4719 scheme (INCOMPATIBILITY):
  4720 
  4721   foo_inject:  "foo$x = foo$y ==> x = y"
  4722   foo_eq:      "(foo$x = foo$y) = (x = y)"
  4723   foo_less:    "(foo$x << foo$y) = (x << y)"
  4724   foo_strict:  "foo$UU = UU"
  4725   foo_defined: "... ==> foo$x ~= UU"
  4726   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  4727 
  4728 
  4729 *** ZF ***
  4730 
  4731 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  4732 including the First Isomorphism Theorem (on quotienting by the kernel
  4733 of a homomorphism).
  4734 
  4735 * ZF/Simplifier: install second copy of type solver that actually
  4736 makes use of TC rules declared to Isar proof contexts (or locales);
  4737 the old version is still required for ML proof scripts.
  4738 
  4739 
  4740 *** Cube ***
  4741 
  4742 * Converted to Isar theory format; use locales instead of axiomatic
  4743 theories.
  4744 
  4745 
  4746 *** ML ***
  4747 
  4748 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  4749 for ||>, ||>>, |>>,
  4750 
  4751 * Pure/library.ML no longer defines its own option datatype, but uses
  4752 that of the SML basis, which has constructors NONE and SOME instead of
  4753 None and Some, as well as exception Option.Option instead of OPTION.
  4754 The functions the, if_none, is_some, is_none have been adapted
  4755 accordingly, while Option.map replaces apsome.
  4756 
  4757 * Pure/library.ML: the exception LIST has been given up in favour of
  4758 the standard exceptions Empty and Subscript, as well as
  4759 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  4760 superceded by the standard hd and tl functions etc.
  4761 
  4762 A number of basic list functions are no longer exported to the ML
  4763 toplevel, as they are variants of predefined functions.  The following
  4764 suggests how one can translate existing code:
  4765 
  4766     rev_append xs ys = List.revAppend (xs, ys)
  4767     nth_elem (i, xs) = List.nth (xs, i)
  4768     last_elem xs = List.last xs
  4769     flat xss = List.concat xss
  4770     seq fs = List.app fs
  4771     partition P xs = List.partition P xs
  4772     mapfilter f xs = List.mapPartial f xs
  4773 
  4774 * Pure/library.ML: several combinators for linear functional
  4775 transformations, notably reverse application and composition:
  4776 
  4777   x |> f                f #> g
  4778   (x, y) |-> f          f #-> g
  4779 
  4780 * Pure/library.ML: introduced/changed precedence of infix operators:
  4781 
  4782   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  4783   infix 2 ?;
  4784   infix 3 o oo ooo oooo;
  4785   infix 4 ~~ upto downto;
  4786 
  4787 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  4788 infix operators.
  4789 
  4790 * Pure/library.ML: natural list combinators fold, fold_rev, and
  4791 fold_map support linear functional transformations and nesting.  For
  4792 example:
  4793 
  4794   fold f [x1, ..., xN] y =
  4795     y |> f x1 |> ... |> f xN
  4796 
  4797   (fold o fold) f [xs1, ..., xsN] y =
  4798     y |> fold f xs1 |> ... |> fold f xsN
  4799 
  4800   fold f [x1, ..., xN] =
  4801     f x1 #> ... #> f xN
  4802 
  4803   (fold o fold) f [xs1, ..., xsN] =
  4804     fold f xs1 #> ... #> fold f xsN
  4805 
  4806 * Pure/library.ML: the following selectors on type 'a option are
  4807 available:
  4808 
  4809   the:               'a option -> 'a  (*partial*)
  4810   these:             'a option -> 'a  where 'a = 'b list
  4811   the_default: 'a -> 'a option -> 'a
  4812   the_list:          'a option -> 'a list
  4813 
  4814 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  4815 basic operations for association lists, following natural argument
  4816 order; moreover the explicit equality predicate passed here avoids
  4817 potentially expensive polymorphic runtime equality checks.
  4818 The old functions may be expressed as follows:
  4819 
  4820   assoc = uncurry (AList.lookup (op =))
  4821   assocs = these oo AList.lookup (op =)
  4822   overwrite = uncurry (AList.update (op =)) o swap
  4823 
  4824 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  4825 
  4826   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  4827   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  4828 
  4829 replacing make_keylist and keyfilter (occassionally used)
  4830 Naive rewrites:
  4831 
  4832   make_keylist = AList.make
  4833   keyfilter = AList.find (op =)
  4834 
  4835 * eq_fst and eq_snd now take explicit equality parameter, thus
  4836   avoiding eqtypes. Naive rewrites:
  4837 
  4838     eq_fst = eq_fst (op =)
  4839     eq_snd = eq_snd (op =)
  4840 
  4841 * Removed deprecated apl and apr (rarely used).
  4842   Naive rewrites:
  4843 
  4844     apl (n, op) =>>= curry op n
  4845     apr (op, m) =>>= fn n => op (n, m)
  4846 
  4847 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  4848 provides a reasonably efficient light-weight implementation of sets as
  4849 lists.
  4850 
  4851 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  4852 few new operations; existing lookup and update are now curried to
  4853 follow natural argument order (for use with fold etc.);
  4854 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  4855 
  4856 * Pure/General: output via the Isabelle channels of
  4857 writeln/warning/error etc. is now passed through Output.output, with a
  4858 hook for arbitrary transformations depending on the print_mode
  4859 (cf. Output.add_mode -- the first active mode that provides a output
  4860 function wins).  Already formatted output may be embedded into further
  4861 text via Output.raw; the result of Pretty.string_of/str_of and derived
  4862 functions (string_of_term/cterm/thm etc.) is already marked raw to
  4863 accommodate easy composition of diagnostic messages etc.  Programmers
  4864 rarely need to care about Output.output or Output.raw at all, with
  4865 some notable exceptions: Output.output is required when bypassing the
  4866 standard channels (writeln etc.), or in token translations to produce
  4867 properly formatted results; Output.raw is required when capturing
  4868 already output material that will eventually be presented to the user
  4869 a second time.  For the default print mode, both Output.output and
  4870 Output.raw have no effect.
  4871 
  4872 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  4873 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  4874 cumulative results are displayed at the end of a batch session.
  4875 
  4876 * Pure/General: File.sysify_path and File.quote_sysify path have been
  4877 replaced by File.platform_path and File.shell_path (with appropriate
  4878 hooks).  This provides a clean interface for unusual systems where the
  4879 internal and external process view of file names are different.
  4880 
  4881 * Pure: more efficient orders for basic syntactic entities: added
  4882 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  4883 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  4884 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  4885 orders now -- potential INCOMPATIBILITY for code that depends on a
  4886 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  4887 Library.sort_strings on result).
  4888 
  4889 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  4890 fold_types traverse types/terms from left to right, observing natural
  4891 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  4892 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  4893 
  4894 * Pure: name spaces have been refined, with significant changes of the
  4895 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  4896 to extern(_table).  The plain name entry path is superceded by a
  4897 general 'naming' context, which also includes the 'policy' to produce
  4898 a fully qualified name and external accesses of a fully qualified
  4899 name; NameSpace.extend is superceded by context dependent
  4900 Sign.declare_name.  Several theory and proof context operations modify
  4901 the naming context.  Especially note Theory.restore_naming and
  4902 ProofContext.restore_naming to get back to a sane state; note that
  4903 Theory.add_path is no longer sufficient to recover from
  4904 Theory.absolute_path in particular.
  4905 
  4906 * Pure: new flags short_names (default false) and unique_names
  4907 (default true) for controlling output of qualified names.  If
  4908 short_names is set, names are printed unqualified.  If unique_names is
  4909 reset, the name prefix is reduced to the minimum required to achieve
  4910 the original result when interning again, even if there is an overlap
  4911 with earlier declarations.
  4912 
  4913 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  4914 now 'extend', and 'merge' gets an additional Pretty.pp argument
  4915 (useful for printing error messages).  INCOMPATIBILITY.
  4916 
  4917 * Pure: major reorganization of the theory context.  Type Sign.sg and
  4918 Theory.theory are now identified, referring to the universal
  4919 Context.theory (see Pure/context.ML).  Actual signature and theory
  4920 content is managed as theory data.  The old code and interfaces were
  4921 spread over many files and structures; the new arrangement introduces
  4922 considerable INCOMPATIBILITY to gain more clarity:
  4923 
  4924   Context -- theory management operations (name, identity, inclusion,
  4925     parents, ancestors, merge, etc.), plus generic theory data;
  4926 
  4927   Sign -- logical signature and syntax operations (declaring consts,
  4928     types, etc.), plus certify/read for common entities;
  4929 
  4930   Theory -- logical theory operations (stating axioms, definitions,
  4931     oracles), plus a copy of logical signature operations (consts,
  4932     types, etc.); also a few basic management operations (Theory.copy,
  4933     Theory.merge, etc.)
  4934 
  4935 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  4936 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  4937 for convenience -- they merely return the theory.
  4938 
  4939 * Pure: type Type.tsig is superceded by theory in most interfaces.
  4940 
  4941 * Pure: the Isar proof context type is already defined early in Pure
  4942 as Context.proof (note that ProofContext.context and Proof.context are
  4943 aliases, where the latter is the preferred name).  This enables other
  4944 Isabelle components to refer to that type even before Isar is present.
  4945 
  4946 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  4947 typeK, constK, axiomK, oracleK), but provide explicit operations for
  4948 any of these kinds.  For example, Sign.intern typeK is now
  4949 Sign.intern_type, Theory.hide_space Sign.typeK is now
  4950 Theory.hide_types.  Also note that former
  4951 Theory.hide_classes/types/consts are now
  4952 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  4953 internalize their arguments!  INCOMPATIBILITY.
  4954 
  4955 * Pure: get_thm interface (of PureThy and ProofContext) expects
  4956 datatype thmref (with constructors Name and NameSelection) instead of
  4957 plain string -- INCOMPATIBILITY;
  4958 
  4959 * Pure: cases produced by proof methods specify options, where NONE
  4960 means to remove case bindings -- INCOMPATIBILITY in
  4961 (RAW_)METHOD_CASES.
  4962 
  4963 * Pure: the following operations retrieve axioms or theorems from a
  4964 theory node or theory hierarchy, respectively:
  4965 
  4966   Theory.axioms_of: theory -> (string * term) list
  4967   Theory.all_axioms_of: theory -> (string * term) list
  4968   PureThy.thms_of: theory -> (string * thm) list
  4969   PureThy.all_thms_of: theory -> (string * thm) list
  4970 
  4971 * Pure: print_tac now outputs the goal through the trace channel.
  4972 
  4973 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  4974 Reference Toplevel.debug (default false) controls detailed printing
  4975 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  4976 controls execution profiling -- set to 1 for time and 2 for space
  4977 (both increase the runtime).
  4978 
  4979 * Isar session: The initial use of ROOT.ML is now always timed,
  4980 i.e. the log will show the actual process times, in contrast to the
  4981 elapsed wall-clock time that the outer shell wrapper produces.
  4982 
  4983 * Simplifier: improved handling of bound variables (nameless
  4984 representation, avoid allocating new strings).  Simprocs that invoke
  4985 the Simplifier recursively should use Simplifier.inherit_bounds to
  4986 avoid local name clashes.  Failure to do so produces warnings
  4987 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  4988 for further details.
  4989 
  4990 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  4991 bindings for all theorems stored within a given theory; this may help
  4992 in porting non-Isar theories to Isar ones, while keeping ML proof
  4993 scripts for the time being.
  4994 
  4995 * ML operator HTML.with_charset specifies the charset begin used for
  4996 generated HTML files.  For example:
  4997 
  4998   HTML.with_charset "utf-8" use_thy "Hebrew";
  4999   HTML.with_charset "utf-8" use_thy "Chinese";
  5000 
  5001 
  5002 *** System ***
  5003 
  5004 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5005 isabelle, isatool etc.).
  5006 
  5007 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5008 isatool doc, isatool mkdir, display_drafts etc.).
  5009 
  5010 * isatool usedir: option -f allows specification of the ML file to be
  5011 used by Isabelle; default is ROOT.ML.
  5012 
  5013 * New isatool version outputs the version identifier of the Isabelle
  5014 distribution being used.
  5015 
  5016 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5017 (containing Boolean satisfiability problems) into Isabelle/HOL
  5018 theories.
  5019 
  5020 
  5021 
  5022 New in Isabelle2004 (April 2004)
  5023 --------------------------------
  5024 
  5025 *** General ***
  5026 
  5027 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5028   Replaces linorder.ML.
  5029 
  5030 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5031   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5032   (\<a>...\<z>), are now considered normal letters, and can therefore
  5033   be used anywhere where an ASCII letter (a...zA...Z) has until
  5034   now. COMPATIBILITY: This obviously changes the parsing of some
  5035   terms, especially where a symbol has been used as a binder, say
  5036   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5037   as an identifier.  Fix it by inserting a space around former
  5038   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5039   existing theory and ML files.
  5040 
  5041 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5042 
  5043 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5044   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5045   a normal (but invisible) letter. For multiple letter subscripts repeat
  5046   \<^isub> like this: x\<^isub>1\<^isub>2.
  5047 
  5048 * Pure: There are now sub-/superscripts that can span more than one
  5049   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5050   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5051   superscript. The new control characters are not identifier parts.
  5052 
  5053 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5054   content of "..." to the latex file instead of \isacntrl... . The "..."
  5055   may consist of any printable characters excluding the end bracket >.
  5056 
  5057 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5058   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5059   declare constants "final", which prevents their being given a definition
  5060   later.  It is useful for constants whose behaviour is fixed axiomatically
  5061   rather than definitionally, such as the meta-logic connectives.
  5062 
  5063 * Pure: 'instance' now handles general arities with general sorts
  5064   (i.e. intersections of classes),
  5065 
  5066 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5067   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5068   It can be changed to alter the colors/layout of generated pages.
  5069 
  5070 
  5071 *** Isar ***
  5072 
  5073 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5074   cut_tac, subgoal_tac and thin_tac:
  5075   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5076     locales are no longer forced to write Isar proof scripts.
  5077     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5078     emulations.
  5079   - INCOMPATIBILITY: names of variables to be instantiated may no
  5080     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5081     This is consistent with the instantiation attribute "where".
  5082 
  5083 * Attributes "where" and "of":
  5084   - Now take type variables of instantiated theorem into account when reading
  5085     the instantiation string.  This fixes a bug that caused instantiated
  5086     theorems to have too special types in some circumstances.
  5087   - "where" permits explicit instantiations of type variables.
  5088 
  5089 * Calculation commands "moreover" and "also" no longer interfere with
  5090   current facts ("this"), admitting arbitrary combinations with "then"
  5091   and derived forms.
  5092 
  5093 * Locales:
  5094   - Goal statements involving the context element "includes" no longer
  5095     generate theorems with internal delta predicates (those ending on
  5096     "_axioms") in the premise.
  5097     Resolve particular premise with <locale>.intro to obtain old form.
  5098   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5099     specification and "includes" elements in goal statement.
  5100   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5101     [intro?] and [elim?] (respectively) by default.
  5102   - Experimental command for instantiation of locales in proof contexts:
  5103         instantiate <label>[<attrs>]: <loc>
  5104     Instantiates locale <loc> and adds all its theorems to the current context
  5105     taking into account their attributes.  Label and attrs are optional
  5106     modifiers, like in theorem declarations.  If present, names of
  5107     instantiated theorems are qualified with <label>, and the attributes
  5108     <attrs> are applied after any attributes these theorems might have already.
  5109       If the locale has assumptions, a chained fact of the form
  5110     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5111     are derived.  The command does not support old-style locales declared
  5112     with "locale (open)".
  5113       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5114 
  5115 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5116   (Isar) contexts.
  5117 
  5118 
  5119 *** HOL ***
  5120 
  5121 * Proof import: new image HOL4 contains the imported library from
  5122   the HOL4 system with about 2500 theorems. It is imported by
  5123   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5124   can be used like any other Isabelle image.  See
  5125   HOL/Import/HOL/README for more information.
  5126 
  5127 * Simplifier:
  5128   - Much improved handling of linear and partial orders.
  5129     Reasoners for linear and partial orders are set up for type classes
  5130     "linorder" and "order" respectively, and are added to the default simpset
  5131     as solvers.  This means that the simplifier can build transitivity chains
  5132     to solve goals from the assumptions.
  5133   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5134     of blast or auto after simplification become unnecessary because the goal
  5135     is solved by simplification already.
  5136 
  5137 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5138     all proved in axiomatic type classes for semirings, rings and fields.
  5139 
  5140 * Numerics:
  5141   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5142     now formalized using the Ring_and_Field theory mentioned above.
  5143   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5144     than before, because now they are set up once in a generic manner.
  5145   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5146     Look for the general versions in Ring_and_Field (and Power if they concern
  5147     exponentiation).
  5148 
  5149 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5150 
  5151 * Records:
  5152   - Record types are now by default printed with their type abbreviation
  5153     instead of the list of all field types. This can be configured via
  5154     the reference "print_record_type_abbr".
  5155   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5156     (not enabled by default).
  5157   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5158     EX x. x = sel r to True (not enabled by default).
  5159   - Tactic "record_split_simp_tac" to split and simplify records added.
  5160 
  5161 * 'specification' command added, allowing for definition by
  5162   specification.  There is also an 'ax_specification' command that
  5163   introduces the new constants axiomatically.
  5164 
  5165 * arith(_tac) is now able to generate counterexamples for reals as well.
  5166 
  5167 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5168 
  5169 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5170   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5171 
  5172 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5173   matrix theory to linear programming.
  5174 
  5175 * Unions and Intersections:
  5176   The latex output syntax of UN and INT has been changed
  5177   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5178   i.e. the index formulae has become a subscript.
  5179   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5180 
  5181 * Unions and Intersections over Intervals:
  5182   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5183   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5184   like in normal math, and corresponding versions for < and for intersection.
  5185 
  5186 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5187   lexicographic dictonary ordering has been added as "lexord".
  5188 
  5189 * ML: the legacy theory structures Int and List have been removed. They had
  5190   conflicted with ML Basis Library structures having the same names.
  5191 
  5192 * 'refute' command added to search for (finite) countermodels.  Only works
  5193   for a fragment of HOL.  The installation of an external SAT solver is
  5194   highly recommended.  See "HOL/Refute.thy" for details.
  5195 
  5196 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5197   formulae under an assignment of free variables to random values.
  5198   In contrast to 'refute', it can deal with inductive datatypes,
  5199   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5200   for examples.
  5201 
  5202 
  5203 *** HOLCF ***
  5204 
  5205 * Streams now come with concatenation and are part of the HOLCF image
  5206 
  5207 
  5208 
  5209 New in Isabelle2003 (May 2003)
  5210 ------------------------------
  5211 
  5212 *** General ***
  5213 
  5214 * Provers/simplifier:
  5215 
  5216   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5217     Assumptions are now subject to complete mutual simplification,
  5218     not just from left to right. The simplifier now preserves
  5219     the order of assumptions.
  5220 
  5221     Potential INCOMPATIBILITY:
  5222 
  5223     -- simp sometimes diverges where the old version did
  5224        not, e.g. invoking simp on the goal
  5225 
  5226         [| P (f x); y = x; f x = f y |] ==> Q
  5227 
  5228        now gives rise to the infinite reduction sequence
  5229 
  5230         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5231 
  5232        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5233        kind of problem.
  5234 
  5235     -- Tactics combining classical reasoner and simplification (such as auto)
  5236        are also affected by this change, because many of them rely on
  5237        simp. They may sometimes diverge as well or yield a different numbers
  5238        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5239        in case of problems. Sometimes subsequent calls to the classical
  5240        reasoner will fail because a preceeding call to the simplifier too
  5241        eagerly simplified the goal, e.g. deleted redundant premises.
  5242 
  5243   - The simplifier trace now shows the names of the applied rewrite rules
  5244 
  5245   - You can limit the number of recursive invocations of the simplifier
  5246     during conditional rewriting (where the simplifie tries to solve the
  5247     conditions before applying the rewrite rule):
  5248     ML "simp_depth_limit := n"
  5249     where n is an integer. Thus you can force termination where previously
  5250     the simplifier would diverge.
  5251 
  5252   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5253 
  5254   - No longer aborts on failed congruence proof.  Instead, the
  5255     congruence is ignored.
  5256 
  5257 * Pure: New generic framework for extracting programs from constructive
  5258   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5259   as HOL/Extraction for some case studies.
  5260 
  5261 * Pure: The main goal of the proof state is no longer shown by default, only
  5262 the subgoals. This behaviour is controlled by a new flag.
  5263    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5264 (ML: Proof.show_main_goal).
  5265 
  5266 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5267 rules whose conclusion matches subgoal 1:
  5268       PG menu: Isabelle/Isar -> Show me -> matching rules
  5269 The rules are ordered by how closely they match the subgoal.
  5270 In particular, rules that solve a subgoal outright are displayed first
  5271 (or rather last, the way they are printed).
  5272 (ML: ProofGeneral.print_intros())
  5273 
  5274 * Pure: New flag trace_unify_fail causes unification to print
  5275 diagnostic information (PG: in trace buffer) when it fails. This is
  5276 useful for figuring out why single step proofs like rule, erule or
  5277 assumption failed.
  5278 
  5279 * Pure: Locale specifications now produce predicate definitions
  5280 according to the body of text (covering assumptions modulo local
  5281 definitions); predicate "loc_axioms" covers newly introduced text,
  5282 while "loc" is cumulative wrt. all included locale expressions; the
  5283 latter view is presented only on export into the global theory
  5284 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5285 on the old view without predicates;
  5286 
  5287 * Pure: predefined locales "var" and "struct" are useful for sharing
  5288 parameters (as in CASL, for example); just specify something like
  5289 ``var x + var y + struct M'' as import;
  5290 
  5291 * Pure: improved thms_containing: proper indexing of facts instead of
  5292 raw theorems; check validity of results wrt. current name space;
  5293 include local facts of proof configuration (also covers active
  5294 locales), cover fixed variables in index; may use "_" in term
  5295 specification; an optional limit for the number of printed facts may
  5296 be given (the default is 40);
  5297 
  5298 * Pure: disallow duplicate fact bindings within new-style theory files
  5299 (batch-mode only);
  5300 
  5301 * Provers: improved induct method: assumptions introduced by case
  5302 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5303 the goal statement); "foo" still refers to all facts collectively;
  5304 
  5305 * Provers: the function blast.overloaded has been removed: all constants
  5306 are regarded as potentially overloaded, which improves robustness in exchange
  5307 for slight decrease in efficiency;
  5308 
  5309 * Provers/linorder: New generic prover for transitivity reasoning over
  5310 linear orders.  Note: this prover is not efficient!
  5311 
  5312 * Isar: preview of problems to finish 'show' now produce an error
  5313 rather than just a warning (in interactive mode);
  5314 
  5315 
  5316 *** HOL ***
  5317 
  5318 * arith(_tac)
  5319 
  5320  - Produces a counter example if it cannot prove a goal.
  5321    Note that the counter example may be spurious if the goal is not a formula
  5322    of quantifier-free linear arithmetic.
  5323    In ProofGeneral the counter example appears in the trace buffer.
  5324 
  5325  - Knows about div k and mod k where k is a numeral of type nat or int.
  5326 
  5327  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5328    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5329    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5330 
  5331 * simp's arithmetic capabilities have been enhanced a bit: it now
  5332 takes ~= in premises into account (by performing a case split);
  5333 
  5334 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5335 are distributed over a sum of terms;
  5336 
  5337 * New tactic "trans_tac" and method "trans" instantiate
  5338 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5339 "<=", "<" and "=").
  5340 
  5341 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5342 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5343 
  5344 * 'typedef' command has new option "open" to suppress the set
  5345 definition;
  5346 
  5347 * functions Min and Max on finite sets have been introduced (theory
  5348 Finite_Set);
  5349 
  5350 * attribute [symmetric] now works for relations as well; it turns
  5351 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5352 
  5353 * induct over a !!-quantified statement (say !!x1..xn):
  5354   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5355 
  5356 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5357 %x. None. Warning: empty_def now refers to the previously hidden definition
  5358 of the empty set.
  5359 
  5360 * Algebra: formalization of classical algebra.  Intended as base for
  5361 any algebraic development in Isabelle.  Currently covers group theory
  5362 (up to Sylow's theorem) and ring theory (Universal Property of
  5363 Univariate Polynomials).  Contributions welcome;
  5364 
  5365 * GroupTheory: deleted, since its material has been moved to Algebra;
  5366 
  5367 * Complex: new directory of the complex numbers with numeric constants,
  5368 nonstandard complex numbers, and some complex analysis, standard and
  5369 nonstandard (Jacques Fleuriot);
  5370 
  5371 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  5372 
  5373 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  5374 Fleuriot);
  5375 
  5376 * Real/HahnBanach: updated and adapted to locales;
  5377 
  5378 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  5379 Gray and Kramer);
  5380 
  5381 * UNITY: added the Meier-Sanders theory of progress sets;
  5382 
  5383 * MicroJava: bytecode verifier and lightweight bytecode verifier
  5384 as abstract algorithms, instantiated to the JVM;
  5385 
  5386 * Bali: Java source language formalization. Type system, operational
  5387 semantics, axiomatic semantics. Supported language features:
  5388 classes, interfaces, objects,virtual methods, static methods,
  5389 static/instance fields, arrays, access modifiers, definite
  5390 assignment, exceptions.
  5391 
  5392 
  5393 *** ZF ***
  5394 
  5395 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  5396 universe, etc.);
  5397 
  5398 * Main ZF: virtually all theories converted to new-style format;
  5399 
  5400 
  5401 *** ML ***
  5402 
  5403 * Pure: Tactic.prove provides sane interface for internal proofs;
  5404 omits the infamous "standard" operation, so this is more appropriate
  5405 than prove_goalw_cterm in many situations (e.g. in simprocs);
  5406 
  5407 * Pure: improved error reporting of simprocs;
  5408 
  5409 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  5410 up simprocs;
  5411 
  5412 
  5413 *** Document preparation ***
  5414 
  5415 * uses \par instead of \\ for line breaks in theory text. This may
  5416 shift some page breaks in large documents. To get the old behaviour
  5417 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  5418 
  5419 * minimized dependencies of isabelle.sty and isabellesym.sty on
  5420 other packages
  5421 
  5422 * \<euro> now needs package babel/greek instead of marvosym (which
  5423 broke \Rightarrow)
  5424 
  5425 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  5426 textcomp package)
  5427 
  5428 
  5429 
  5430 New in Isabelle2002 (March 2002)
  5431 --------------------------------
  5432 
  5433 *** Document preparation ***
  5434 
  5435 * greatly simplified document preparation setup, including more
  5436 graceful interpretation of isatool usedir -i/-d/-D options, and more
  5437 instructive isatool mkdir; users should basically be able to get
  5438 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  5439 users may run a separate document processing stage manually like this:
  5440 "isatool usedir -D output HOL Test && isatool document Test/output";
  5441 
  5442 * theory dependency graph may now be incorporated into documents;
  5443 isatool usedir -g true will produce session_graph.eps/.pdf for use
  5444 with \includegraphics of LaTeX;
  5445 
  5446 * proper spacing of consecutive markup elements, especially text
  5447 blocks after section headings;
  5448 
  5449 * support bold style (for single symbols only), input syntax is like
  5450 this: "\<^bold>\<alpha>" or "\<^bold>A";
  5451 
  5452 * \<bullet> is now output as bold \cdot by default, which looks much
  5453 better in printed text;
  5454 
  5455 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  5456 note that these symbols are currently unavailable in Proof General /
  5457 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  5458 
  5459 * isatool latex no longer depends on changed TEXINPUTS, instead
  5460 isatool document copies the Isabelle style files to the target
  5461 location;
  5462 
  5463 
  5464 *** Isar ***
  5465 
  5466 * Pure/Provers: improved proof by cases and induction;
  5467   - 'case' command admits impromptu naming of parameters (such as
  5468     "case (Suc n)");
  5469   - 'induct' method divinates rule instantiation from the inductive
  5470     claim; no longer requires excessive ?P bindings for proper
  5471     instantiation of cases;
  5472   - 'induct' method properly enumerates all possibilities of set/type
  5473     rules; as a consequence facts may be also passed through *type*
  5474     rules without further ado;
  5475   - 'induct' method now derives symbolic cases from the *rulified*
  5476     rule (before it used to rulify cases stemming from the internal
  5477     atomized version); this means that the context of a non-atomic
  5478     statement becomes is included in the hypothesis, avoiding the
  5479     slightly cumbersome show "PROP ?case" form;
  5480   - 'induct' may now use elim-style induction rules without chaining
  5481     facts, using ``missing'' premises from the goal state; this allows
  5482     rules stemming from inductive sets to be applied in unstructured
  5483     scripts, while still benefitting from proper handling of non-atomic
  5484     statements; NB: major inductive premises need to be put first, all
  5485     the rest of the goal is passed through the induction;
  5486   - 'induct' proper support for mutual induction involving non-atomic
  5487     rule statements (uses the new concept of simultaneous goals, see
  5488     below);
  5489   - append all possible rule selections, but only use the first
  5490     success (no backtracking);
  5491   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  5492   - undeclared rule case names default to numbers 1, 2, 3, ...;
  5493   - added 'print_induct_rules' (covered by help item in recent Proof
  5494     General versions);
  5495   - moved induct/cases attributes to Pure, methods to Provers;
  5496   - generic method setup instantiated for FOL and HOL;
  5497 
  5498 * Pure: support multiple simultaneous goal statements, for example
  5499 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  5500 meta-level mechanism, this acts as if several individual goals had
  5501 been stated separately; in particular common proof methods need to be
  5502 repeated in order to cover all claims; note that a single elimination
  5503 step is *not* sufficient to establish the two conjunctions, so this
  5504 fails:
  5505 
  5506   assume "A & B" then have A and B ..   (*".." fails*)
  5507 
  5508 better use "obtain" in situations as above; alternative refer to
  5509 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  5510 
  5511 * Pure: proper integration with ``locales''; unlike the original
  5512 version by Florian Kammller, Isar locales package high-level proof
  5513 contexts rather than raw logical ones (e.g. we admit to include
  5514 attributes everywhere); operations on locales include merge and
  5515 rename; support for implicit arguments (``structures''); simultaneous
  5516 type-inference over imports and text; see also HOL/ex/Locales.thy for
  5517 some examples;
  5518 
  5519 * Pure: the following commands have been ``localized'', supporting a
  5520 target locale specification "(in name)": 'lemma', 'theorem',
  5521 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  5522 stored both within the locale and at the theory level (exported and
  5523 qualified by the locale name);
  5524 
  5525 * Pure: theory goals may now be specified in ``long'' form, with
  5526 ad-hoc contexts consisting of arbitrary locale elements. for example
  5527 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  5528 definitions may be given, too); the result is a meta-level rule with
  5529 the context elements being discharged in the obvious way;
  5530 
  5531 * Pure: new proof command 'using' allows to augment currently used
  5532 facts after a goal statement ('using' is syntactically analogous to
  5533 'apply', but acts on the goal's facts only); this allows chained facts
  5534 to be separated into parts given before and after a claim, as in
  5535 ``from a and b have C using d and e <proof>'';
  5536 
  5537 * Pure: renamed "antecedent" case to "rule_context";
  5538 
  5539 * Pure: new 'judgment' command records explicit information about the
  5540 object-logic embedding (used by several tools internally); no longer
  5541 use hard-wired "Trueprop";
  5542 
  5543 * Pure: added 'corollary' command;
  5544 
  5545 * Pure: fixed 'token_translation' command;
  5546 
  5547 * Pure: removed obsolete 'exported' attribute;
  5548 
  5549 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  5550 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  5551 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  5552 
  5553 * Pure: method 'atomize' presents local goal premises as object-level
  5554 statements (atomic meta-level propositions); setup controlled via
  5555 rewrite rules declarations of 'atomize' attribute; example
  5556 application: 'induct' method with proper rule statements in improper
  5557 proof *scripts*;
  5558 
  5559 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  5560 now consider the syntactic context of assumptions, giving a better
  5561 chance to get type-inference of the arguments right (this is
  5562 especially important for locales);
  5563 
  5564 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  5565 mode;
  5566 
  5567 * Pure/obtain: the formal conclusion "thesis", being marked as
  5568 ``internal'', may no longer be reference directly in the text;
  5569 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  5570 situations;
  5571 
  5572 * Pure: generic 'sym' attribute which declares a rule both as pure
  5573 'elim?' and for the 'symmetric' operation;
  5574 
  5575 * Pure: marginal comments ``--'' may now occur just anywhere in the
  5576 text; the fixed correlation with particular command syntax has been
  5577 discontinued;
  5578 
  5579 * Pure: new method 'rules' is particularly well-suited for proof
  5580 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  5581 but often produces more compact proof terms with less detours;
  5582 
  5583 * Pure/Provers/classical: simplified integration with pure rule
  5584 attributes and methods; the classical "intro?/elim?/dest?"
  5585 declarations coincide with the pure ones; the "rule" method no longer
  5586 includes classically swapped intros; "intro" and "elim" methods no
  5587 longer pick rules from the context; also got rid of ML declarations
  5588 AddXIs/AddXEs/AddXDs; all of this has some potential for
  5589 INCOMPATIBILITY;
  5590 
  5591 * Provers/classical: attribute 'swapped' produces classical inversions
  5592 of introduction rules;
  5593 
  5594 * Provers/simplifier: 'simplified' attribute may refer to explicit
  5595 rules instead of full simplifier context; 'iff' attribute handles
  5596 conditional rules;
  5597 
  5598 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  5599 
  5600 * HOL: 'recdef' now fails on unfinished automated proofs, use
  5601 "(permissive)" option to recover old behavior;
  5602 
  5603 * HOL: 'inductive' no longer features separate (collective) attributes
  5604 for 'intros' (was found too confusing);
  5605 
  5606 * HOL: properly declared induction rules less_induct and
  5607 wf_induct_rule;
  5608 
  5609 
  5610 *** HOL ***
  5611 
  5612 * HOL: moved over to sane numeral syntax; the new policy is as
  5613 follows:
  5614 
  5615   - 0 and 1 are polymorphic constants, which are defined on any
  5616   numeric type (nat, int, real etc.);
  5617 
  5618   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  5619   binary representation internally;
  5620 
  5621   - type nat has special constructor Suc, and generally prefers Suc 0
  5622   over 1::nat and Suc (Suc 0) over 2::nat;
  5623 
  5624 This change may cause significant problems of INCOMPATIBILITY; here
  5625 are some hints on converting existing sources:
  5626 
  5627   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  5628   entities, so expressions involving "-" (unary or binary minus) need
  5629   to be spaced properly;
  5630 
  5631   - existing occurrences of "1" may need to be constraint "1::nat" or
  5632   even replaced by Suc 0; similar for old "2";
  5633 
  5634   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  5635 
  5636   - remove all special provisions on numerals in proofs;
  5637 
  5638 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  5639 representation (depends on bin_arith_simps in the default context);
  5640 
  5641 * HOL: symbolic syntax for x^2 (numeral 2);
  5642 
  5643 * HOL: the class of all HOL types is now called "type" rather than
  5644 "term"; INCOMPATIBILITY, need to adapt references to this type class
  5645 in axclass/classes, instance/arities, and (usually rare) occurrences
  5646 in typings (of consts etc.); internally the class is called
  5647 "HOL.type", ML programs should refer to HOLogic.typeS;
  5648 
  5649 * HOL/record package improvements:
  5650   - new derived operations "fields" to build a partial record section,
  5651     "extend" to promote a fixed record to a record scheme, and
  5652     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  5653     declared as simp by default;
  5654   - shared operations ("more", "fields", etc.) now need to be always
  5655     qualified) --- potential INCOMPATIBILITY;
  5656   - removed "make_scheme" operations (use "make" with "extend") --
  5657     INCOMPATIBILITY;
  5658   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  5659   - provides cases/induct rules for use with corresponding Isar
  5660     methods (for concrete records, record schemes, concrete more
  5661     parts, and schematic more parts -- in that order);
  5662   - internal definitions directly based on a light-weight abstract
  5663     theory of product types over typedef rather than datatype;
  5664 
  5665 * HOL: generic code generator for generating executable ML code from
  5666 specifications; specific support for HOL constructs such as inductive
  5667 datatypes and sets, as well as recursive functions; can be invoked
  5668 via 'generate_code' theory section;
  5669 
  5670 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  5671 
  5672 * HOL: consolidated and renamed several theories.  In particular:
  5673         Ord.thy has been absorbed into HOL.thy
  5674         String.thy has been absorbed into List.thy
  5675 
  5676 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  5677 (beware of argument permutation!);
  5678 
  5679 * HOL: linorder_less_split superseded by linorder_cases;
  5680 
  5681 * HOL/List: "nodups" renamed to "distinct";
  5682 
  5683 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  5684 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  5685   - Ex_def has changed, now need to use some_eq_ex
  5686 
  5687 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  5688 in this (rare) case use:
  5689 
  5690   delSWrapper "split_all_tac"
  5691   addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
  5692 
  5693 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
  5694 MAY FAIL;
  5695 
  5696 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
  5697 Isabelle's type classes, ^ on functions and relations has too general
  5698 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be
  5699 necessary to attach explicit type constraints;
  5700 
  5701 * HOL/Relation: the prefix name of the infix "O" has been changed from
  5702 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been
  5703 renamed accordingly (eg "compI" -> "rel_compI").
  5704 
  5705 * HOL: syntax translations now work properly with numerals and records
  5706 expressions;
  5707 
  5708 * HOL: bounded abstraction now uses syntax "%" / "\<lambda>" instead
  5709 of "lam" -- INCOMPATIBILITY;
  5710 
  5711 * HOL: got rid of some global declarations (potential INCOMPATIBILITY
  5712 for ML tools): const "()" renamed "Product_Type.Unity", type "unit"
  5713 renamed "Product_Type.unit";
  5714 
  5715 * HOL: renamed rtrancl_into_rtrancl2 to converse_rtrancl_into_rtrancl
  5716 
  5717 * HOL: removed obsolete theorem "optionE" (use "option.exhaust", or
  5718 the "cases" method);
  5719 
  5720 * HOL/GroupTheory: group theory examples including Sylow's theorem (by
  5721 Florian Kammller);
  5722 
  5723 * HOL/IMP: updated and converted to new-style theory format; several
  5724 parts turned into readable document, with proper Isar proof texts and
  5725 some explanations (by Gerwin Klein);
  5726 
  5727 * HOL-Real: added Complex_Numbers (by Gertrud Bauer);
  5728 
  5729 * HOL-Hyperreal is now a logic image;
  5730 
  5731 
  5732 *** HOLCF ***
  5733 
  5734 * Isar: consts/constdefs supports mixfix syntax for continuous
  5735 operations;
  5736 
  5737 * Isar: domain package adapted to new-style theory format, e.g. see
  5738 HOLCF/ex/Dnat.thy;
  5739 
  5740 * theory Lift: proper use of rep_datatype lift instead of ML hacks --
  5741 potential INCOMPATIBILITY; now use plain induct_tac instead of former
  5742 lift.induct_tac, always use UU instead of Undef;
  5743 
  5744 * HOLCF/IMP: updated and converted to new-style theory;
  5745 
  5746 
  5747 *** ZF ***
  5748 
  5749 * Isar: proper integration of logic-specific tools and packages,
  5750 including theory commands '(co)inductive', '(co)datatype',
  5751 'rep_datatype', 'inductive_cases', as well as methods 'ind_cases',
  5752 'induct_tac', 'case_tac', and 'typecheck' (with attribute 'TC');
  5753 
  5754 * theory Main no longer includes AC; for the Axiom of Choice, base
  5755 your theory on Main_ZFC;
  5756 
  5757 * the integer library now covers quotients and remainders, with many
  5758 laws relating division to addition, multiplication, etc.;
  5759 
  5760 * ZF/UNITY: Chandy and Misra's UNITY is now available in ZF, giving a
  5761 typeless version of the formalism;
  5762 
  5763 * ZF/AC, Coind, IMP, Resid: updated and converted to new-style theory
  5764 format;
  5765 
  5766 * ZF/Induct: new directory for examples of inductive definitions,
  5767 including theory Multiset for multiset orderings; converted to
  5768 new-style theory format;
  5769 
  5770 * ZF: many new theorems about lists, ordinals, etc.;
  5771 
  5772 
  5773 *** General ***
  5774 
  5775 * Pure/kernel: meta-level proof terms (by Stefan Berghofer); reference
  5776 variable proof controls level of detail: 0 = no proofs (only oracle
  5777 dependencies), 1 = lemma dependencies, 2 = compact proof terms; see
  5778 also ref manual for further ML interfaces;
  5779 
  5780 * Pure/axclass: removed obsolete ML interface
  5781 goal_subclass/goal_arity;
  5782 
  5783 * Pure/syntax: new token syntax "num" for plain numerals (without "#"
  5784 of "xnum"); potential INCOMPATIBILITY, since -0, -1 etc. are now
  5785 separate tokens, so expressions involving minus need to be spaced
  5786 properly;
  5787 
  5788 * Pure/syntax: support non-oriented infixes, using keyword "infix"
  5789 rather than "infixl" or "infixr";
  5790 
  5791 * Pure/syntax: concrete syntax for dummy type variables admits genuine
  5792 sort constraint specifications in type inference; e.g. "x::_::foo"
  5793 ensures that the type of "x" is of sort "foo" (but not necessarily a
  5794 type variable);
  5795 
  5796 * Pure/syntax: print modes "type_brackets" and "no_type_brackets"
  5797 control output of nested => (types); the default behavior is
  5798 "type_brackets";
  5799 
  5800 * Pure/syntax: builtin parse translation for "_constify" turns valued
  5801 tokens into AST constants;
  5802 
  5803 * Pure/syntax: prefer later declarations of translations and print
  5804 translation functions; potential INCOMPATIBILITY: need to reverse
  5805 multiple declarations for same syntax element constant;
  5806 
  5807 * Pure/show_hyps reset by default (in accordance to existing Isar
  5808 practice);
  5809 
  5810 * Provers/classical: renamed addaltern to addafter, addSaltern to
  5811 addSafter;
  5812 
  5813 * Provers/clasimp: ``iff'' declarations now handle conditional rules
  5814 as well;
  5815 
  5816 * system: tested support for MacOS X; should be able to get Isabelle +
  5817 Proof General to work in a plain Terminal after installing Poly/ML
  5818 (e.g. from the Isabelle distribution area) and GNU bash alone
  5819 (e.g. from http://www.apple.com); full X11, XEmacs and X-Symbol
  5820 support requires further installations, e.g. from
  5821 http://fink.sourceforge.net/);
  5822 
  5823 * system: support Poly/ML 4.1.1 (able to manage larger heaps);
  5824 
  5825 * system: reduced base memory usage by Poly/ML (approx. 20 MB instead
  5826 of 40 MB), cf. ML_OPTIONS;
  5827 
  5828 * system: Proof General keywords specification is now part of the
  5829 Isabelle distribution (see etc/isar-keywords.el);
  5830 
  5831 * system: support for persistent Proof General sessions (refrain from
  5832 outdating all loaded theories on startup); user may create writable
  5833 logic images like this: ``isabelle -q HOL Test'';
  5834 
  5835 * system: smart selection of Isabelle process versus Isabelle
  5836 interface, accommodates case-insensitive file systems (e.g. HFS+); may
  5837 run both "isabelle" and "Isabelle" even if file names are badly
  5838 damaged (executable inspects the case of the first letter of its own
  5839 name); added separate "isabelle-process" and "isabelle-interface";
  5840 
  5841 * system: refrain from any attempt at filtering input streams; no
  5842 longer support ``8bit'' encoding of old isabelle font, instead proper
  5843 iso-latin characters may now be used; the related isatools
  5844 "symbolinput" and "nonascii" have disappeared as well;
  5845 
  5846 * system: removed old "xterm" interface (the print modes "xterm" and
  5847 "xterm_color" are still available for direct use in a suitable
  5848 terminal);
  5849 
  5850 
  5851 
  5852 New in Isabelle99-2 (February 2001)
  5853 -----------------------------------
  5854 
  5855 *** Overview of INCOMPATIBILITIES ***
  5856 
  5857 * HOL: please note that theories in the Library and elsewhere often use the
  5858 new-style (Isar) format; to refer to their theorems in an ML script you must
  5859 bind them to ML identifers by e.g.      val thm_name = thm "thm_name";
  5860 
  5861 * HOL: inductive package no longer splits induction rule aggressively,
  5862 but only as far as specified by the introductions given; the old
  5863 format may be recovered via ML function complete_split_rule or attribute
  5864 'split_rule (complete)';
  5865 
  5866 * HOL: induct renamed to lfp_induct, lfp_Tarski to lfp_unfold,
  5867 gfp_Tarski to gfp_unfold;
  5868 
  5869 * HOL: contrapos, contrapos2 renamed to contrapos_nn, contrapos_pp;
  5870 
  5871 * HOL: infix "dvd" now has priority 50 rather than 70 (because it is a
  5872 relation); infix "^^" has been renamed "``"; infix "``" has been
  5873 renamed "`"; "univalent" has been renamed "single_valued";
  5874 
  5875 * HOL/Real: "rinv" and "hrinv" replaced by overloaded "inverse"
  5876 operation;
  5877 
  5878 * HOLCF: infix "`" has been renamed "$"; the symbol syntax is \<cdot>;
  5879 
  5880 * Isar: 'obtain' no longer declares "that" fact as simp/intro;
  5881 
  5882 * Isar/HOL: method 'induct' now handles non-atomic goals; as a
  5883 consequence, it is no longer monotonic wrt. the local goal context
  5884 (which is now passed through the inductive cases);
  5885 
  5886 * Document preparation: renamed standard symbols \<ll> to \<lless> and
  5887 \<gg> to \<ggreater>;
  5888 
  5889 
  5890 *** Document preparation ***
  5891 
  5892 * \isabellestyle{NAME} selects version of Isabelle output (currently
  5893 available: are "it" for near math-mode best-style output, "sl" for
  5894 slanted text style, and "tt" for plain type-writer; if no
  5895 \isabellestyle command is given, output is according to slanted
  5896 type-writer);
  5897 
  5898 * support sub/super scripts (for single symbols only), input syntax is
  5899 like this: "A\<^sup>*" or "A\<^sup>\<star>";
  5900 
  5901 * some more standard symbols; see Appendix A of the system manual for
  5902 the complete list of symbols defined in isabellesym.sty;
  5903 
  5904 * improved isabelle style files; more abstract symbol implementation
  5905 (should now use \isamath{...} and \isatext{...} in custom symbol
  5906 definitions);
  5907 
  5908 * antiquotation @{goals} and @{subgoals} for output of *dynamic* goals
  5909 state; Note that presentation of goal states does not conform to
  5910 actual human-readable proof documents.  Please do not include goal
  5911 states into document output unless you really know what you are doing!
  5912 
  5913 * proper indentation of antiquoted output with proportional LaTeX
  5914 fonts;
  5915 
  5916 * no_document ML operator temporarily disables LaTeX document
  5917 generation;
  5918 
  5919 * isatool unsymbolize tunes sources for plain ASCII communication;
  5920 
  5921 
  5922 *** Isar ***
  5923 
  5924 * Pure: Isar now suffers initial goal statements to contain unbound
  5925 schematic variables (this does not conform to actual readable proof
  5926 documents, due to unpredictable outcome and non-compositional proof
  5927 checking); users who know what they are doing may use schematic goals
  5928 for Prolog-style synthesis of proven results;
  5929 
  5930 * Pure: assumption method (an implicit finishing) now handles actual
  5931 rules as well;
  5932 
  5933 * Pure: improved 'obtain' --- moved to Pure, insert "that" into
  5934 initial goal, declare "that" only as Pure intro (only for single
  5935 steps); the "that" rule assumption may now be involved in implicit
  5936 finishing, thus ".." becomes a feasible for trivial obtains;
  5937 
  5938 * Pure: default proof step now includes 'intro_classes'; thus trivial
  5939 instance proofs may be performed by "..";
  5940 
  5941 * Pure: ?thesis / ?this / "..." now work for pure meta-level
  5942 statements as well;
  5943 
  5944 * Pure: more robust selection of calculational rules;
  5945 
  5946 * Pure: the builtin notion of 'finished' goal now includes the ==-refl
  5947 rule (as well as the assumption rule);
  5948 
  5949 * Pure: 'thm_deps' command visualizes dependencies of theorems and
  5950 lemmas, using the graph browser tool;
  5951 
  5952 * Pure: predict failure of "show" in interactive mode;
  5953 
  5954 * Pure: 'thms_containing' now takes actual terms as arguments;
  5955 
  5956 * HOL: improved method 'induct' --- now handles non-atomic goals
  5957 (potential INCOMPATIBILITY); tuned error handling;
  5958 
  5959 * HOL: cases and induct rules now provide explicit hints about the
  5960 number of facts to be consumed (0 for "type" and 1 for "set" rules);
  5961 any remaining facts are inserted into the goal verbatim;
  5962 
  5963 * HOL: local contexts (aka cases) may now contain term bindings as
  5964 well; the 'cases' and 'induct' methods new provide a ?case binding for
  5965 the result to be shown in each case;
  5966 
  5967 * HOL: added 'recdef_tc' command;
  5968 
  5969 * isatool convert assists in eliminating legacy ML scripts;
  5970 
  5971 
  5972 *** HOL ***
  5973 
  5974 * HOL/Library: a collection of generic theories to be used together
  5975 with main HOL; the theory loader path already includes this directory
  5976 by default; the following existing theories have been moved here:
  5977 HOL/Induct/Multiset, HOL/Induct/Acc (as Accessible_Part), HOL/While
  5978 (as While_Combinator), HOL/Lex/Prefix (as List_Prefix);
  5979 
  5980 * HOL/Unix: "Some aspects of Unix file-system security", a typical
  5981 modelling and verification task performed in Isabelle/HOL +
  5982 Isabelle/Isar + Isabelle document preparation (by Markus Wenzel).
  5983 
  5984 * HOL/Algebra: special summation operator SUM no longer exists, it has
  5985 been replaced by setsum; infix 'assoc' now has priority 50 (like
  5986 'dvd'); axiom 'one_not_zero' has been moved from axclass 'ring' to
  5987 'domain', this makes the theory consistent with mathematical
  5988 literature;
  5989 
  5990 * HOL basics: added overloaded operations "inverse" and "divide"
  5991 (infix "/"), syntax for generic "abs" operation, generic summation
  5992 operator \<Sum>;
  5993 
  5994 * HOL/typedef: simplified package, provide more useful rules (see also
  5995 HOL/subset.thy);
  5996 
  5997 * HOL/datatype: induction rule for arbitrarily branching datatypes is
  5998 now expressed as a proper nested rule (old-style tactic scripts may
  5999 require atomize_strip_tac to cope with non-atomic premises);
  6000 
  6001 * HOL: renamed theory "Prod" to "Product_Type", renamed "split" rule
  6002 to "split_conv" (old name still available for compatibility);
  6003 
  6004 * HOL: improved concrete syntax for strings (e.g. allows translation
  6005 rules with string literals);
  6006 
  6007 * HOL-Real-Hyperreal: this extends HOL-Real with the hyperreals
  6008  and Fleuriot's mechanization of analysis, including the transcendental
  6009  functions for the reals;
  6010 
  6011 * HOL/Real, HOL/Hyperreal: improved arithmetic simplification;
  6012 
  6013 
  6014 *** CTT ***
  6015 
  6016 * CTT: x-symbol support for Pi, Sigma, -->, : (membership); note that
  6017 "lam" is displayed as TWO lambda-symbols
  6018 
  6019 * CTT: theory Main now available, containing everything (that is, Bool
  6020 and Arith);
  6021 
  6022 
  6023 *** General ***
  6024 
  6025 * Pure: the Simplifier has been implemented properly as a derived rule
  6026 outside of the actual kernel (at last!); the overall performance
  6027 penalty in practical applications is about 50%, while reliability of
  6028 the Isabelle inference kernel has been greatly improved;
  6029 
  6030 * print modes "brackets" and "no_brackets" control output of nested =>
  6031 (types) and ==> (props); the default behaviour is "brackets";
  6032 
  6033 * Provers: fast_tac (and friends) now handle actual object-logic rules
  6034 as assumptions as well;
  6035 
  6036 * system: support Poly/ML 4.0;
  6037 
  6038 * system: isatool install handles KDE version 1 or 2;
  6039 
  6040 
  6041 
  6042 New in Isabelle99-1 (October 2000)
  6043 ----------------------------------
  6044 
  6045 *** Overview of INCOMPATIBILITIES ***
  6046 
  6047 * HOL: simplification of natural numbers is much changed; to partly
  6048 recover the old behaviour (e.g. to prevent n+n rewriting to #2*n)
  6049 issue the following ML commands:
  6050 
  6051   Delsimprocs Nat_Numeral_Simprocs.cancel_numerals;
  6052   Delsimprocs [Nat_Numeral_Simprocs.combine_numerals];
  6053 
  6054 * HOL: simplification no longer dives into case-expressions; this is
  6055 controlled by "t.weak_case_cong" for each datatype t;
  6056 
  6057 * HOL: nat_less_induct renamed to less_induct;
  6058 
  6059 * HOL: systematic renaming of the SOME (Eps) rules, may use isatool
  6060 fixsome to patch .thy and .ML sources automatically;
  6061 
  6062   select_equality  -> some_equality
  6063   select_eq_Ex     -> some_eq_ex
  6064   selectI2EX       -> someI2_ex
  6065   selectI2         -> someI2
  6066   selectI          -> someI
  6067   select1_equality -> some1_equality
  6068   Eps_sym_eq       -> some_sym_eq_trivial
  6069   Eps_eq           -> some_eq_trivial
  6070 
  6071 * HOL: exhaust_tac on datatypes superceded by new generic case_tac;
  6072 
  6073 * HOL: removed obsolete theorem binding expand_if (refer to split_if
  6074 instead);
  6075 
  6076 * HOL: the recursion equations generated by 'recdef' are now called
  6077 f.simps instead of f.rules;
  6078 
  6079 * HOL: qed_spec_mp now also handles bounded ALL as well;
  6080 
  6081 * HOL: 0 is now overloaded, so the type constraint ":: nat" may
  6082 sometimes be needed;
  6083 
  6084 * HOL: the constant for "f``x" is now "image" rather than "op ``";
  6085 
  6086 * HOL: the constant for "f-``x" is now "vimage" rather than "op -``";
  6087 
  6088 * HOL: the disjoint sum is now "<+>" instead of "Plus"; the cartesian
  6089 product is now "<*>" instead of "Times"; the lexicographic product is
  6090 now "<*lex*>" instead of "**";
  6091 
  6092 * HOL: theory Sexp is now in HOL/Induct examples (it used to be part
  6093 of main HOL, but was unused); better use HOL's datatype package;
  6094 
  6095 * HOL: removed "symbols" syntax for constant "override" of theory Map;
  6096 the old syntax may be recovered as follows:
  6097 
  6098   syntax (symbols)
  6099     override  :: "('a ~=> 'b) => ('a ~=> 'b) => ('a ~=> 'b)"
  6100       (infixl "\\<oplus>" 100)
  6101 
  6102 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  6103 
  6104 * HOL/ML: even fewer consts are declared as global (see theories Ord,
  6105 Lfp, Gfp, WF); this only affects ML packages that refer to const names
  6106 internally;
  6107 
  6108 * HOL and ZF: syntax for quotienting wrt an equivalence relation
  6109 changed from A/r to A//r;
  6110 
  6111 * ZF: new treatment of arithmetic (nat & int) may break some old
  6112 proofs;
  6113 
  6114 * Isar: renamed some attributes (RS -> THEN, simplify -> simplified,
  6115 rulify -> rule_format, elimify -> elim_format, ...);
  6116 
  6117 * Isar/Provers: intro/elim/dest attributes changed; renamed
  6118 intro/intro!/intro!! flags to intro!/intro/intro? (in most cases, one
  6119 should have to change intro!! to intro? only); replaced "delrule" by
  6120 "rule del";
  6121 
  6122 * Isar/HOL: renamed "intrs" to "intros" in inductive definitions;
  6123 
  6124 * Provers: strengthened force_tac by using new first_best_tac;
  6125 
  6126 * LaTeX document preparation: several changes of isabelle.sty (see
  6127 lib/texinputs);
  6128 
  6129 
  6130 *** Document preparation ***
  6131 
  6132 * formal comments (text blocks etc.) in new-style theories may now
  6133 contain antiquotations of thm/prop/term/typ/text to be presented
  6134 according to latex print mode; concrete syntax is like this:
  6135 @{term[show_types] "f(x) = a + x"};
  6136 
  6137 * isatool mkdir provides easy setup of Isabelle session directories,
  6138 including proper document sources;
  6139 
  6140 * generated LaTeX sources are now deleted after successful run
  6141 (isatool document -c); may retain a copy somewhere else via -D option
  6142 of isatool usedir;
  6143 
  6144 * isatool usedir -D now lets isatool latex -o sty update the Isabelle
  6145 style files, achieving self-contained LaTeX sources and simplifying
  6146 LaTeX debugging;
  6147 
  6148 * old-style theories now produce (crude) LaTeX output as well;
  6149 
  6150 * browser info session directories are now self-contained (may be put
  6151 on WWW server seperately); improved graphs of nested sessions; removed
  6152 graph for 'all sessions';
  6153 
  6154 * several improvements in isabelle style files; \isabellestyle{it}
  6155 produces fake math mode output; \isamarkupheader is now \section by
  6156 default; see lib/texinputs/isabelle.sty etc.;
  6157 
  6158 
  6159 *** Isar ***
  6160 
  6161 * Isar/Pure: local results and corresponding term bindings are now
  6162 subject to Hindley-Milner polymorphism (similar to ML); this
  6163 accommodates incremental type-inference very nicely;
  6164 
  6165 * Isar/Pure: new derived language element 'obtain' supports
  6166 generalized existence reasoning;
  6167 
  6168 * Isar/Pure: new calculational elements 'moreover' and 'ultimately'
  6169 support accumulation of results, without applying any rules yet;
  6170 useful to collect intermediate results without explicit name
  6171 references, and for use with transitivity rules with more than 2
  6172 premises;
  6173 
  6174 * Isar/Pure: scalable support for case-analysis type proofs: new
  6175 'case' language element refers to local contexts symbolically, as
  6176 produced by certain proof methods; internally, case names are attached
  6177 to theorems as "tags";
  6178 
  6179 * Isar/Pure: theory command 'hide' removes declarations from
  6180 class/type/const name spaces;
  6181 
  6182 * Isar/Pure: theory command 'defs' supports option "(overloaded)" to
  6183 indicate potential overloading;
  6184 
  6185 * Isar/Pure: changed syntax of local blocks from {{ }} to { };
  6186 
  6187 * Isar/Pure: syntax of sorts made 'inner', i.e. have to write
  6188 "{a,b,c}" instead of {a,b,c};
  6189 
  6190 * Isar/Pure now provides its own version of intro/elim/dest
  6191 attributes; useful for building new logics, but beware of confusion
  6192 with the version in Provers/classical;
  6193 
  6194 * Isar/Pure: the local context of (non-atomic) goals is provided via
  6195 case name 'antecedent';
  6196 
  6197 * Isar/Pure: removed obsolete 'transfer' attribute (transfer of thms
  6198 to the current context is now done automatically);
  6199 
  6200 * Isar/Pure: theory command 'method_setup' provides a simple interface
  6201 for definining proof methods in ML;
  6202 
  6203 * Isar/Provers: intro/elim/dest attributes changed; renamed
  6204 intro/intro!/intro!! flags to intro!/intro/intro? (INCOMPATIBILITY, in
  6205 most cases, one should have to change intro!! to intro? only);
  6206 replaced "delrule" by "rule del";
  6207 
  6208 * Isar/Provers: new 'hypsubst' method, plain 'subst' method and
  6209 'symmetric' attribute (the latter supercedes [RS sym]);
  6210 
  6211 * Isar/Provers: splitter support (via 'split' attribute and 'simp'
  6212 method modifier); 'simp' method: 'only:' modifier removes loopers as
  6213 well (including splits);
  6214 
  6215 * Isar/Provers: Simplifier and Classical methods now support all kind
  6216 of modifiers used in the past, including 'cong', 'iff', etc.
  6217 
  6218 * Isar/Provers: added 'fastsimp' and 'clarsimp' methods (combination
  6219 of Simplifier and Classical reasoner);
  6220 
  6221 * Isar/HOL: new proof method 'cases' and improved version of 'induct'
  6222 now support named cases; major packages (inductive, datatype, primrec,
  6223 recdef) support case names and properly name parameters;
  6224 
  6225 * Isar/HOL: new transitivity rules for substitution in inequalities --
  6226 monotonicity conditions are extracted to be proven at end of
  6227 calculations;
  6228 
  6229 * Isar/HOL: removed 'case_split' thm binding, should use 'cases' proof
  6230 method anyway;
  6231 
  6232 * Isar/HOL: removed old expand_if = split_if; theorems if_splits =
  6233 split_if split_if_asm; datatype package provides theorems foo.splits =
  6234 foo.split foo.split_asm for each datatype;
  6235 
  6236 * Isar/HOL: tuned inductive package, rename "intrs" to "intros"
  6237 (potential INCOMPATIBILITY), emulation of mk_cases feature for proof