NEWS
author huffman
Sat Oct 16 16:22:42 2010 -0700 (2010-10-16)
changeset 40026 8f8f18a88685
parent 39963 626b1d360d42
child 39993 eebfa0b93896
permissions -rw-r--r--
remove last few dependencies on domain_library.ML and delete it; temporarily disable emptiness check
     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 * Theory SetsAndFunctions has been split into Function_Algebras and Set_Algebras;
   107 canonical names for instance definitions for functions; various improvements.
   108 INCOMPATIBILITY.
   109 
   110 * Records: logical foundation type for records do not carry a '_type' suffix
   111 any longer.  INCOMPATIBILITY.
   112 
   113 * Code generation for records: more idiomatic representation of record types.
   114 Warning: records are not covered by ancient SML code generation any longer.
   115 INCOMPATIBILITY.  In cases of need, a suitable rep_datatype declaration
   116 helps to succeed then:
   117 
   118   record 'a foo = ...
   119   ...
   120   rep_datatype foo_ext ...
   121 
   122 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   123 INCOMPATIBILITY.
   124 
   125 * Quickcheck in locales considers interpretations of that locale for
   126 counter example search.
   127 
   128 * Theory Library/Monad_Syntax provides do-syntax for monad types.  Syntax
   129 in Library/State_Monad has been changed to avoid ambiguities.
   130 INCOMPATIBILITY.
   131 
   132 * Code generator: export_code without explicit file declaration prints
   133 to standard output.  INCOMPATIBILITY.
   134 
   135 * Abolished symbol type names:  "prod" and "sum" replace "*" and "+"
   136 respectively.  INCOMPATIBILITY.
   137 
   138 * Constant "split" has been merged with constant "prod_case";  names
   139 of ML functions, facts etc. involving split have been retained so far,
   140 though.  INCOMPATIBILITY.
   141 
   142 * Dropped old infix syntax "mem" for List.member;  use "in set"
   143 instead.  INCOMPATIBILITY.
   144 
   145 * Refactoring of code-generation specific operations in List.thy
   146 
   147   constants
   148     null ~> List.null
   149 
   150   facts
   151     mem_iff ~> member_def
   152     null_empty ~> null_def
   153 
   154 INCOMPATIBILITY.  Note that these were not suppossed to be used
   155 regularly unless for striking reasons;  their main purpose was code
   156 generation.
   157 
   158 * Some previously unqualified names have been qualified:
   159 
   160   types
   161     bool ~> HOL.bool
   162     nat ~> Nat.nat
   163 
   164   constants
   165     Trueprop ~> HOL.Trueprop
   166     True ~> HOL.True
   167     False ~> HOL.False
   168     op & ~> HOL.conj
   169     op | ~> HOL.disj
   170     op --> ~> HOL.implies
   171     op = ~> HOL.eq
   172     Not ~> HOL.Not
   173     The ~> HOL.The
   174     All ~> HOL.All
   175     Ex ~> HOL.Ex
   176     Ex1 ~> HOL.Ex1
   177     Let ~> HOL.Let
   178     If ~> HOL.If
   179     Ball ~> Set.Ball
   180     Bex ~> Set.Bex
   181     Suc ~> Nat.Suc
   182     Pair ~> Product_Type.Pair
   183     fst ~> Product_Type.fst
   184     snd ~> Product_Type.snd
   185     curry ~> Product_Type.curry
   186     op : ~> Set.member
   187     Collect ~> Set.Collect
   188 
   189 INCOMPATIBILITY.
   190 
   191 * Removed simplifier congruence rule of "prod_case", as has for long
   192 been the case with "split".  INCOMPATIBILITY.
   193 
   194 * Datatype package: theorems generated for executable equality
   195 (class eq) carry proper names and are treated as default code
   196 equations.
   197 
   198 * Removed lemma Option.is_none_none (Duplicate of is_none_def).
   199 INCOMPATIBILITY.
   200 
   201 * List.thy: use various operations from the Haskell prelude when
   202 generating Haskell code.
   203 
   204 * Multiset.thy: renamed empty_idemp -> empty_neutral
   205 
   206 * code_simp.ML and method code_simp: simplification with rules determined
   207 by code generator.
   208 
   209 * code generator: do not print function definitions for case
   210 combinators any longer.
   211 
   212 * Multivariate Analysis: Introduced a type class for euclidean space. Most
   213 theorems are now stated in terms of euclidean spaces instead of finite
   214 cartesian products.
   215 
   216   types
   217     real ^ 'n ~>  'a::real_vector
   218               ~>  'a::euclidean_space
   219               ~>  'a::ordered_euclidean_space
   220         (depends on your needs)
   221 
   222   constants
   223      _ $ _        ~> _ $$ _
   224      \<chi> x. _  ~> \<chi>\<chi> x. _
   225      CARD('n)     ~> DIM('a)
   226 
   227 Also note that the indices are now natural numbers and not from some finite
   228 type. Finite cartesian products of euclidean spaces, products of euclidean
   229 spaces the real and complex numbers are instantiated to be euclidean_spaces.
   230 
   231 INCOMPATIBILITY.
   232 
   233 * Probability: Introduced pinfreal as real numbers with infinity. Use pinfreal
   234 as value for measures. Introduces Lebesgue Measure based on the integral in
   235 Multivariate Analysis. Proved Radon Nikodym for arbitrary sigma finite measure
   236 spaces.
   237 
   238  INCOMPATIBILITY.
   239 
   240 * Inductive package: offers new command "inductive_simps" to automatically
   241 derive instantiated and simplified equations for inductive predicates,
   242 similar to inductive_cases.
   243 
   244 * "bij f" is now an abbreviation of "bij_betw f UNIV UNIV". surj_on is a
   245 generalization of surj, and "surj f" is now a abbreviation of "surj_on f UNIV".
   246 The theorems bij_def and surj_def are unchanged.
   247 
   248 * Function package: .psimps rules are no longer implicitly declared [simp].
   249 INCOMPATIBILITY.
   250 
   251 * Weaker versions of the "meson" and "metis" proof methods are now available in
   252   "HOL-Plain", without dependency on "Hilbert_Choice". The proof methods become
   253   more powerful after "Hilbert_Choice" is loaded in "HOL-Main".
   254 
   255 * MESON: Renamed lemmas:
   256   meson_not_conjD ~> Meson.not_conjD
   257   meson_not_disjD ~> Meson.not_disjD
   258   meson_not_notD ~> Meson.not_notD
   259   meson_not_allD ~> Meson.not_allD
   260   meson_not_exD ~> Meson.not_exD
   261   meson_imp_to_disjD ~> Meson.imp_to_disjD
   262   meson_not_impD ~> Meson.not_impD
   263   meson_iff_to_disjD ~> Meson.iff_to_disjD
   264   meson_not_iffD ~> Meson.not_iffD
   265   meson_not_refl_disj_D ~> Meson.not_refl_disj_D
   266   meson_conj_exD1 ~> Meson.conj_exD1
   267   meson_conj_exD2 ~> Meson.conj_exD2
   268   meson_disj_exD ~> Meson.disj_exD
   269   meson_disj_exD1 ~> Meson.disj_exD1
   270   meson_disj_exD2 ~> Meson.disj_exD2
   271   meson_disj_assoc ~> Meson.disj_assoc
   272   meson_disj_comm ~> Meson.disj_comm
   273   meson_disj_FalseD1 ~> Meson.disj_FalseD1
   274   meson_disj_FalseD2 ~> Meson.disj_FalseD2
   275 INCOMPATIBILITY.
   276 
   277 * Sledgehammer: Renamed lemmas:
   278   COMBI_def ~> Meson.COMBI_def
   279   COMBK_def ~> Meson.COMBK_def
   280   COMBB_def ~> Meson.COMBB_def
   281   COMBC_def ~> Meson.COMBC_def
   282   COMBS_def ~> Meson.COMBS_def
   283   abs_I ~> Meson.abs_I
   284   abs_K ~> Meson.abs_K
   285   abs_B ~> Meson.abs_B
   286   abs_C ~> Meson.abs_C
   287   abs_S ~> Meson.abs_S
   288 INCOMPATIBILITY.
   289 
   290 
   291 *** FOL ***
   292 
   293 * All constant names are now qualified.  INCOMPATIBILITY.
   294 
   295 
   296 *** ZF ***
   297 
   298 * All constant names are now qualified.  INCOMPATIBILITY.
   299 
   300 
   301 *** ML ***
   302 
   303 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   304 meaning.
   305 
   306 * Renamed structure PureThy to Pure_Thy and moved most of its
   307 operations to structure Global_Theory, to emphasize that this is
   308 rarely-used global-only stuff.
   309 
   310 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
   311 instead (or tracing for high-volume output).
   312 
   313 * Configuration option show_question_marks only affects regular pretty
   314 printing of types and terms, not raw Term.string_of_vname.
   315 
   316 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
   317 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
   318 @{thms} for most purposes.
   319 
   320 * ML structure Unsynchronized never opened, not even in Isar
   321 interaction mode as before.  Old Unsynchronized.set etc. have been
   322 discontinued -- use plain := instead.  This should be *rare* anyway,
   323 since modern tools always work via official context data, notably
   324 configuration options.
   325 
   326 * ML antiquotations @{theory} and @{theory_ref} refer to named
   327 theories from the ancestry of the current context, not any accidental
   328 theory loader state as before.  Potential INCOMPATIBILITY, subtle
   329 change in semantics.
   330 
   331 * Parallel and asynchronous execution requires special care concerning
   332 interrupts.  Structure Exn provides some convenience functions that
   333 avoid working directly with raw Interrupt.  User code must not absorb
   334 interrupts -- intermediate handling (for cleanup etc.) needs to be
   335 followed by re-raising of the original exception.  Another common
   336 source of mistakes are "handle _" patterns, which make the meaning of
   337 the program subject to physical effects of the environment.
   338 
   339 
   340 *** System ***
   341 
   342 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   343 
   344 
   345 
   346 New in Isabelle2009-2 (June 2010)
   347 ---------------------------------
   348 
   349 *** General ***
   350 
   351 * Authentic syntax for *all* logical entities (type classes, type
   352 constructors, term constants): provides simple and robust
   353 correspondence between formal entities and concrete syntax.  Within
   354 the parse tree / AST representations, "constants" are decorated by
   355 their category (class, type, const) and spelled out explicitly with
   356 their full internal name.
   357 
   358 Substantial INCOMPATIBILITY concerning low-level syntax declarations
   359 and translations (translation rules and translation functions in ML).
   360 Some hints on upgrading:
   361 
   362   - Many existing uses of 'syntax' and 'translations' can be replaced
   363     by more modern 'type_notation', 'notation' and 'abbreviation',
   364     which are independent of this issue.
   365 
   366   - 'translations' require markup within the AST; the term syntax
   367     provides the following special forms:
   368 
   369       CONST c   -- produces syntax version of constant c from context
   370       XCONST c  -- literally c, checked as constant from context
   371       c         -- literally c, if declared by 'syntax'
   372 
   373     Plain identifiers are treated as AST variables -- occasionally the
   374     system indicates accidental variables via the error "rhs contains
   375     extra variables".
   376 
   377     Type classes and type constructors are marked according to their
   378     concrete syntax.  Some old translations rules need to be written
   379     for the "type" category, using type constructor application
   380     instead of pseudo-term application of the default category
   381     "logic".
   382 
   383   - 'parse_translation' etc. in ML may use the following
   384     antiquotations:
   385 
   386       @{class_syntax c}   -- type class c within parse tree / AST
   387       @{term_syntax c}    -- type constructor c within parse tree / AST
   388       @{const_syntax c}   -- ML version of "CONST c" above
   389       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
   390 
   391   - Literal types within 'typed_print_translations', i.e. those *not*
   392     represented as pseudo-terms are represented verbatim.  Use @{class
   393     c} or @{type_name c} here instead of the above syntax
   394     antiquotations.
   395 
   396 Note that old non-authentic syntax was based on unqualified base
   397 names, so all of the above "constant" names would coincide.  Recall
   398 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
   399 diagnose syntax problems.
   400 
   401 * Type constructors admit general mixfix syntax, not just infix.
   402 
   403 * Concrete syntax may be attached to local entities without a proof
   404 body, too.  This works via regular mixfix annotations for 'fix',
   405 'def', 'obtain' etc. or via the explicit 'write' command, which is
   406 similar to the 'notation' command in theory specifications.
   407 
   408 * Discontinued unnamed infix syntax (legacy feature for many years) --
   409 need to specify constant name and syntax separately.  Internal ML
   410 datatype constructors have been renamed from InfixName to Infix etc.
   411 Minor INCOMPATIBILITY.
   412 
   413 * Schematic theorem statements need to be explicitly markup as such,
   414 via commands 'schematic_lemma', 'schematic_theorem',
   415 'schematic_corollary'.  Thus the relevance of the proof is made
   416 syntactically clear, which impacts performance in a parallel or
   417 asynchronous interactive environment.  Minor INCOMPATIBILITY.
   418 
   419 * Use of cumulative prems via "!" in some proof methods has been
   420 discontinued (old legacy feature).
   421 
   422 * References 'trace_simp' and 'debug_simp' have been replaced by
   423 configuration options stored in the context. Enabling tracing (the
   424 case of debugging is similar) in proofs works via
   425 
   426   using [[trace_simp = true]]
   427 
   428 Tracing is then active for all invocations of the simplifier in
   429 subsequent goal refinement steps. Tracing may also still be enabled or
   430 disabled via the ProofGeneral settings menu.
   431 
   432 * Separate commands 'hide_class', 'hide_type', 'hide_const',
   433 'hide_fact' replace the former 'hide' KIND command.  Minor
   434 INCOMPATIBILITY.
   435 
   436 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
   437 more efficient than combinations with -q1 or -q2.
   438 
   439 
   440 *** Pure ***
   441 
   442 * Proofterms record type-class reasoning explicitly, using the
   443 "unconstrain" operation internally.  This eliminates all sort
   444 constraints from a theorem and proof, introducing explicit
   445 OFCLASS-premises.  On the proof term level, this operation is
   446 automatically applied at theorem boundaries, such that closed proofs
   447 are always free of sort constraints.  INCOMPATIBILITY for tools that
   448 inspect proof terms.
   449 
   450 * Local theory specifications may depend on extra type variables that
   451 are not present in the result type -- arguments TYPE('a) :: 'a itself
   452 are added internally.  For example:
   453 
   454   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
   455 
   456 * Predicates of locales introduced by classes carry a mandatory
   457 "class" prefix.  INCOMPATIBILITY.
   458 
   459 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
   460 
   461 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
   462 'class' instead.
   463 
   464 * Command 'code_reflect' allows to incorporate generated ML code into
   465 runtime environment; replaces immature code_datatype antiquotation.
   466 INCOMPATIBILITY.
   467 
   468 * Code generator: simple concept for abstract datatypes obeying
   469 invariants.
   470 
   471 * Code generator: details of internal data cache have no impact on the
   472 user space functionality any longer.
   473 
   474 * Methods "unfold_locales" and "intro_locales" ignore non-locale
   475 subgoals.  This is more appropriate for interpretations with 'where'.
   476 INCOMPATIBILITY.
   477 
   478 * Command 'example_proof' opens an empty proof body.  This allows to
   479 experiment with Isar, without producing any persistent result.
   480 
   481 * Commands 'type_notation' and 'no_type_notation' declare type syntax
   482 within a local theory context, with explicit checking of the
   483 constructors involved (in contrast to the raw 'syntax' versions).
   484 
   485 * Commands 'types' and 'typedecl' now work within a local theory
   486 context -- without introducing dependencies on parameters or
   487 assumptions, which is not possible in Isabelle/Pure.
   488 
   489 * Command 'defaultsort' has been renamed to 'default_sort', it works
   490 within a local theory context.  Minor INCOMPATIBILITY.
   491 
   492 
   493 *** HOL ***
   494 
   495 * Command 'typedef' now works within a local theory context -- without
   496 introducing dependencies on parameters or assumptions, which is not
   497 possible in Isabelle/Pure/HOL.  Note that the logical environment may
   498 contain multiple interpretations of local typedefs (with different
   499 non-emptiness proofs), even in a global theory context.
   500 
   501 * New package for quotient types.  Commands 'quotient_type' and
   502 'quotient_definition' may be used for defining types and constants by
   503 quotient constructions.  An example is the type of integers created by
   504 quotienting pairs of natural numbers:
   505 
   506   fun
   507     intrel :: "(nat * nat) => (nat * nat) => bool"
   508   where
   509     "intrel (x, y) (u, v) = (x + v = u + y)"
   510 
   511   quotient_type int = "nat * nat" / intrel
   512     by (auto simp add: equivp_def expand_fun_eq)
   513 
   514   quotient_definition
   515     "0::int" is "(0::nat, 0::nat)"
   516 
   517 The method "lifting" can be used to lift of theorems from the
   518 underlying "raw" type to the quotient type.  The example
   519 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
   520 construction and provides a reasoning infrastructure for finite sets.
   521 
   522 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
   523 clash with new theory Quotient in Main HOL.
   524 
   525 * Moved the SMT binding into the main HOL session, eliminating
   526 separate HOL-SMT session.
   527 
   528 * List membership infix mem operation is only an input abbreviation.
   529 INCOMPATIBILITY.
   530 
   531 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
   532 for future developements; former Library/Word.thy is still present in
   533 the AFP entry RSAPPS.
   534 
   535 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
   536 longer shadowed.  INCOMPATIBILITY.
   537 
   538 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
   539 INCOMPATIBILITY.
   540 
   541 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
   542 INCOMPATIBILITY.
   543 
   544 * Dropped normalizing_semiring etc; use the facts in semiring classes
   545 instead.  INCOMPATIBILITY.
   546 
   547 * Dropped several real-specific versions of lemmas about floor and
   548 ceiling; use the generic lemmas from theory "Archimedean_Field"
   549 instead.  INCOMPATIBILITY.
   550 
   551   floor_number_of_eq         ~> floor_number_of
   552   le_floor_eq_number_of      ~> number_of_le_floor
   553   le_floor_eq_zero           ~> zero_le_floor
   554   le_floor_eq_one            ~> one_le_floor
   555   floor_less_eq_number_of    ~> floor_less_number_of
   556   floor_less_eq_zero         ~> floor_less_zero
   557   floor_less_eq_one          ~> floor_less_one
   558   less_floor_eq_number_of    ~> number_of_less_floor
   559   less_floor_eq_zero         ~> zero_less_floor
   560   less_floor_eq_one          ~> one_less_floor
   561   floor_le_eq_number_of      ~> floor_le_number_of
   562   floor_le_eq_zero           ~> floor_le_zero
   563   floor_le_eq_one            ~> floor_le_one
   564   floor_subtract_number_of   ~> floor_diff_number_of
   565   floor_subtract_one         ~> floor_diff_one
   566   ceiling_number_of_eq       ~> ceiling_number_of
   567   ceiling_le_eq_number_of    ~> ceiling_le_number_of
   568   ceiling_le_zero_eq         ~> ceiling_le_zero
   569   ceiling_le_eq_one          ~> ceiling_le_one
   570   less_ceiling_eq_number_of  ~> number_of_less_ceiling
   571   less_ceiling_eq_zero       ~> zero_less_ceiling
   572   less_ceiling_eq_one        ~> one_less_ceiling
   573   ceiling_less_eq_number_of  ~> ceiling_less_number_of
   574   ceiling_less_eq_zero       ~> ceiling_less_zero
   575   ceiling_less_eq_one        ~> ceiling_less_one
   576   le_ceiling_eq_number_of    ~> number_of_le_ceiling
   577   le_ceiling_eq_zero         ~> zero_le_ceiling
   578   le_ceiling_eq_one          ~> one_le_ceiling
   579   ceiling_subtract_number_of ~> ceiling_diff_number_of
   580   ceiling_subtract_one       ~> ceiling_diff_one
   581 
   582 * Theory "Finite_Set": various folding_XXX locales facilitate the
   583 application of the various fold combinators on finite sets.
   584 
   585 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
   586 provides abstract red-black tree type which is backed by "RBT_Impl" as
   587 implementation.  INCOMPATIBILTY.
   588 
   589 * Theory Library/Coinductive_List has been removed -- superseded by
   590 AFP/thys/Coinductive.
   591 
   592 * Theory PReal, including the type "preal" and related operations, has
   593 been removed.  INCOMPATIBILITY.
   594 
   595 * Real: new development using Cauchy Sequences.
   596 
   597 * Split off theory "Big_Operators" containing setsum, setprod,
   598 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
   599 
   600 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
   601 "Int" etc.  INCOMPATIBILITY.
   602 
   603 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
   604 
   605 * New set of rules "ac_simps" provides combined assoc / commute
   606 rewrites for all interpretations of the appropriate generic locales.
   607 
   608 * Renamed theory "OrderedGroup" to "Groups" and split theory
   609 "Ring_and_Field" into theories "Rings" and "Fields"; for more
   610 appropriate and more consistent names suitable for name prefixes
   611 within the HOL theories.  INCOMPATIBILITY.
   612 
   613 * Some generic constants have been put to appropriate theories:
   614   - less_eq, less: Orderings
   615   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
   616   - inverse, divide: Rings
   617 INCOMPATIBILITY.
   618 
   619 * More consistent naming of type classes involving orderings (and
   620 lattices):
   621 
   622     lower_semilattice                   ~> semilattice_inf
   623     upper_semilattice                   ~> semilattice_sup
   624 
   625     dense_linear_order                  ~> dense_linorder
   626 
   627     pordered_ab_group_add               ~> ordered_ab_group_add
   628     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
   629     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
   630     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
   631     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
   632     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
   633     pordered_cancel_semiring            ~> ordered_cancel_semiring
   634     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
   635     pordered_comm_ring                  ~> ordered_comm_ring
   636     pordered_comm_semiring              ~> ordered_comm_semiring
   637     pordered_ring                       ~> ordered_ring
   638     pordered_ring_abs                   ~> ordered_ring_abs
   639     pordered_semiring                   ~> ordered_semiring
   640 
   641     ordered_ab_group_add                ~> linordered_ab_group_add
   642     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
   643     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
   644     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
   645     ordered_field                       ~> linordered_field
   646     ordered_field_no_lb                 ~> linordered_field_no_lb
   647     ordered_field_no_ub                 ~> linordered_field_no_ub
   648     ordered_field_dense_linear_order    ~> dense_linordered_field
   649     ordered_idom                        ~> linordered_idom
   650     ordered_ring                        ~> linordered_ring
   651     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
   652     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
   653     ordered_ring_strict                 ~> linordered_ring_strict
   654     ordered_semidom                     ~> linordered_semidom
   655     ordered_semiring                    ~> linordered_semiring
   656     ordered_semiring_1                  ~> linordered_semiring_1
   657     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
   658     ordered_semiring_strict             ~> linordered_semiring_strict
   659 
   660   The following slightly odd type classes have been moved to a
   661   separate theory Library/Lattice_Algebras:
   662 
   663     lordered_ab_group_add               ~> lattice_ab_group_add
   664     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
   665     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
   666     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
   667     lordered_ring                       ~> lattice_ring
   668 
   669 INCOMPATIBILITY.
   670 
   671 * Refined field classes:
   672   - classes division_ring_inverse_zero, field_inverse_zero,
   673     linordered_field_inverse_zero include rule inverse 0 = 0 --
   674     subsumes former division_by_zero class;
   675   - numerous lemmas have been ported from field to division_ring.
   676 INCOMPATIBILITY.
   677 
   678 * Refined algebra theorem collections:
   679   - dropped theorem group group_simps, use algebra_simps instead;
   680   - dropped theorem group ring_simps, use field_simps instead;
   681   - proper theorem collection field_simps subsumes former theorem
   682     groups field_eq_simps and field_simps;
   683   - dropped lemma eq_minus_self_iff which is a duplicate for
   684     equal_neg_zero.
   685 INCOMPATIBILITY.
   686 
   687 * Theory Finite_Set and List: some lemmas have been generalized from
   688 sets to lattices:
   689 
   690   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
   691   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
   692   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
   693   union_Union_fold_union        ~> sup_Sup_fold_sup
   694   Inter_fold_inter              ~> Inf_fold_inf
   695   Union_fold_union              ~> Sup_fold_sup
   696   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
   697   union_UNION_fold_union        ~> sup_SUPR_fold_sup
   698   INTER_fold_inter              ~> INFI_fold_inf
   699   UNION_fold_union              ~> SUPR_fold_sup
   700 
   701 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
   702 replaced by the more convenient lemmas Inf_empty and Sup_empty.
   703 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
   704 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
   705 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
   706 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
   707 
   708 * Reorganized theory Multiset: swapped notation of pointwise and
   709 multiset order:
   710 
   711   - pointwise ordering is instance of class order with standard syntax
   712     <= and <;
   713   - multiset ordering has syntax <=# and <#; partial order properties
   714     are provided by means of interpretation with prefix
   715     multiset_order;
   716   - less duplication, less historical organization of sections,
   717     conversion from associations lists to multisets, rudimentary code
   718     generation;
   719   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
   720     if needed.
   721 
   722 Renamed:
   723 
   724   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
   725   multi_count_ext  ~>  multiset_ext
   726   diff_union_inverse2  ~>  diff_union_cancelR
   727 
   728 INCOMPATIBILITY.
   729 
   730 * Theory Permutation: replaced local "remove" by List.remove1.
   731 
   732 * Code generation: ML and OCaml code is decorated with signatures.
   733 
   734 * Theory List: added transpose.
   735 
   736 * Library/Nat_Bijection.thy is a collection of bijective functions
   737 between nat and other types, which supersedes the older libraries
   738 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
   739 
   740   Constants:
   741   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
   742   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
   743   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
   744   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
   745   Countable.pair_encode           ~> prod_encode
   746   NatIso.prod2nat                 ~> prod_encode
   747   NatIso.nat2prod                 ~> prod_decode
   748   NatIso.sum2nat                  ~> sum_encode
   749   NatIso.nat2sum                  ~> sum_decode
   750   NatIso.list2nat                 ~> list_encode
   751   NatIso.nat2list                 ~> list_decode
   752   NatIso.set2nat                  ~> set_encode
   753   NatIso.nat2set                  ~> set_decode
   754 
   755   Lemmas:
   756   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
   757   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
   758   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
   759   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
   760   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
   761   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
   762   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
   763   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
   764   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
   765   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
   766   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
   767   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
   768   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
   769 
   770 * Sledgehammer:
   771   - Renamed ATP commands:
   772     atp_info     ~> sledgehammer running_atps
   773     atp_kill     ~> sledgehammer kill_atps
   774     atp_messages ~> sledgehammer messages
   775     atp_minimize ~> sledgehammer minimize
   776     print_atps   ~> sledgehammer available_atps
   777     INCOMPATIBILITY.
   778   - Added user's manual ("isabelle doc sledgehammer").
   779   - Added option syntax and "sledgehammer_params" to customize
   780     Sledgehammer's behavior.  See the manual for details.
   781   - Modified the Isar proof reconstruction code so that it produces
   782     direct proofs rather than proofs by contradiction.  (This feature
   783     is still experimental.)
   784   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
   785     full-typed mode.
   786   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
   787 
   788 * Nitpick:
   789   - Added and implemented "binary_ints" and "bits" options.
   790   - Added "std" option and implemented support for nonstandard models.
   791   - Added and implemented "finitize" option to improve the precision
   792     of infinite datatypes based on a monotonicity analysis.
   793   - Added support for quotient types.
   794   - Added support for "specification" and "ax_specification"
   795     constructs.
   796   - Added support for local definitions (for "function" and
   797     "termination" proofs).
   798   - Added support for term postprocessors.
   799   - Optimized "Multiset.multiset" and "FinFun.finfun".
   800   - Improved efficiency of "destroy_constrs" optimization.
   801   - Fixed soundness bugs related to "destroy_constrs" optimization and
   802     record getters.
   803   - Fixed soundness bug related to higher-order constructors.
   804   - Fixed soundness bug when "full_descrs" is enabled.
   805   - Improved precision of set constructs.
   806   - Added "atoms" option.
   807   - Added cache to speed up repeated Kodkod invocations on the same
   808     problems.
   809   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
   810     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
   811     "SAT4J_Light".  INCOMPATIBILITY.
   812   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
   813     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
   814   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
   815 
   816 * Method "induct" now takes instantiations of the form t, where t is not
   817   a variable, as a shorthand for "x == t", where x is a fresh variable.
   818   If this is not intended, t has to be enclosed in parentheses.
   819   By default, the equalities generated by definitional instantiations
   820   are pre-simplified, which may cause parameters of inductive cases
   821   to disappear, or may even delete some of the inductive cases.
   822   Use "induct (no_simp)" instead of "induct" to restore the old
   823   behaviour. The (no_simp) option is also understood by the "cases"
   824   and "nominal_induct" methods, which now perform pre-simplification, too.
   825   INCOMPATIBILITY.
   826 
   827 
   828 *** HOLCF ***
   829 
   830 * Variable names in lemmas generated by the domain package have
   831 changed; the naming scheme is now consistent with the HOL datatype
   832 package.  Some proof scripts may be affected, INCOMPATIBILITY.
   833 
   834 * The domain package no longer defines the function "foo_copy" for
   835 recursive domain "foo".  The reach lemma is now stated directly in
   836 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
   837 be reformulated in terms of "foo_take", INCOMPATIBILITY.
   838 
   839 * Most definedness lemmas generated by the domain package (previously
   840 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
   841 like "foo$x = UU <-> x = UU", which works better as a simp rule.
   842 Proofs that used definedness lemmas as intro rules may break,
   843 potential INCOMPATIBILITY.
   844 
   845 * Induction and casedist rules generated by the domain package now
   846 declare proper case_names (one called "bottom", and one named for each
   847 constructor).  INCOMPATIBILITY.
   848 
   849 * For mutually-recursive domains, separate "reach" and "take_lemma"
   850 rules are generated for each domain, INCOMPATIBILITY.
   851 
   852   foo_bar.reach       ~> foo.reach  bar.reach
   853   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
   854 
   855 * Some lemmas generated by the domain package have been renamed for
   856 consistency with the datatype package, INCOMPATIBILITY.
   857 
   858   foo.ind        ~> foo.induct
   859   foo.finite_ind ~> foo.finite_induct
   860   foo.coind      ~> foo.coinduct
   861   foo.casedist   ~> foo.exhaust
   862   foo.exhaust    ~> foo.nchotomy
   863 
   864 * For consistency with other definition packages, the fixrec package
   865 now generates qualified theorem names, INCOMPATIBILITY.
   866 
   867   foo_simps  ~> foo.simps
   868   foo_unfold ~> foo.unfold
   869   foo_induct ~> foo.induct
   870 
   871 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
   872 method and internal fixrec proofs now use the default simpset instead.
   873 INCOMPATIBILITY.
   874 
   875 * The "contlub" predicate has been removed.  Proof scripts should use
   876 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
   877 
   878 * The "admw" predicate has been removed, INCOMPATIBILITY.
   879 
   880 * The constants cpair, cfst, and csnd have been removed in favor of
   881 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
   882 
   883 
   884 *** ML ***
   885 
   886 * Antiquotations for basic formal entities:
   887 
   888     @{class NAME}         -- type class
   889     @{class_syntax NAME}  -- syntax representation of the above
   890 
   891     @{type_name NAME}     -- logical type
   892     @{type_abbrev NAME}   -- type abbreviation
   893     @{nonterminal NAME}   -- type of concrete syntactic category
   894     @{type_syntax NAME}   -- syntax representation of any of the above
   895 
   896     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
   897     @{const_abbrev NAME}  -- abbreviated constant
   898     @{const_syntax NAME}  -- syntax representation of any of the above
   899 
   900 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
   901 syntax constant (cf. 'syntax' command).
   902 
   903 * Antiquotation @{make_string} inlines a function to print arbitrary
   904 values similar to the ML toplevel.  The result is compiler dependent
   905 and may fall back on "?" in certain situations.
   906 
   907 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
   908 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
   909 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
   910 not work with the asynchronous Isar document model.
   911 
   912 * Configuration options now admit dynamic default values, depending on
   913 the context or even global references.
   914 
   915 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
   916 uses an efficient external library if available (for Poly/ML).
   917 
   918 * Renamed some important ML structures, while keeping the old names
   919 for some time as aliases within the structure Legacy:
   920 
   921   OuterKeyword  ~>  Keyword
   922   OuterLex      ~>  Token
   923   OuterParse    ~>  Parse
   924   OuterSyntax   ~>  Outer_Syntax
   925   PrintMode     ~>  Print_Mode
   926   SpecParse     ~>  Parse_Spec
   927   ThyInfo       ~>  Thy_Info
   928   ThyLoad       ~>  Thy_Load
   929   ThyOutput     ~>  Thy_Output
   930   TypeInfer     ~>  Type_Infer
   931 
   932 Note that "open Legacy" simplifies porting of sources, but forgetting
   933 to remove it again will complicate porting again in the future.
   934 
   935 * Most operations that refer to a global context are named
   936 accordingly, e.g. Simplifier.global_context or
   937 ProofContext.init_global.  There are some situations where a global
   938 context actually works, but under normal circumstances one needs to
   939 pass the proper local context through the code!
   940 
   941 * Discontinued old TheoryDataFun with its copy/init operation -- data
   942 needs to be pure.  Functor Theory_Data_PP retains the traditional
   943 Pretty.pp argument to merge, which is absent in the standard
   944 Theory_Data version.
   945 
   946 * Sorts.certify_sort and derived "cert" operations for types and terms
   947 no longer minimize sorts.  Thus certification at the boundary of the
   948 inference kernel becomes invariant under addition of class relations,
   949 which is an important monotonicity principle.  Sorts are now minimized
   950 in the syntax layer only, at the boundary between the end-user and the
   951 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
   952 explicitly in rare situations.
   953 
   954 * Renamed old-style Drule.standard to Drule.export_without_context, to
   955 emphasize that this is in no way a standard operation.
   956 INCOMPATIBILITY.
   957 
   958 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
   959 usual for resolution.  Rare INCOMPATIBILITY.
   960 
   961 * Renamed varify/unvarify operations to varify_global/unvarify_global
   962 to emphasize that these only work in a global situation (which is
   963 quite rare).
   964 
   965 * Curried take and drop in library.ML; negative length is interpreted
   966 as infinity (as in chop).  Subtle INCOMPATIBILITY.
   967 
   968 * Proof terms: type substitutions on proof constants now use canonical
   969 order of type variables.  INCOMPATIBILITY for tools working with proof
   970 terms.
   971 
   972 * Raw axioms/defs may no longer carry sort constraints, and raw defs
   973 may no longer carry premises.  User-level specifications are
   974 transformed accordingly by Thm.add_axiom/add_def.
   975 
   976 
   977 *** System ***
   978 
   979 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
   980 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
   981 proof terms are enabled unconditionally in the new HOL-Proofs image.
   982 
   983 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
   984 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
   985 respectively.
   986 
   987 * Old lib/scripts/polyml-platform is superseded by the
   988 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
   989 variant, even on a 64 bit machine.  The following example setting
   990 prefers 64 bit if available:
   991 
   992   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
   993 
   994 * The preliminary Isabelle/jEdit application demonstrates the emerging
   995 Isabelle/Scala layer for advanced prover interaction and integration.
   996 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
   997 component.
   998 
   999 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1000 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1001 similar to the default assignment of the document preparation system
  1002 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1003 provides some operations for direct access to the font without asking
  1004 the user for manual installation.
  1005 
  1006 
  1007 
  1008 New in Isabelle2009-1 (December 2009)
  1009 -------------------------------------
  1010 
  1011 *** General ***
  1012 
  1013 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1014 one backslash should be used, even in ML sources.
  1015 
  1016 
  1017 *** Pure ***
  1018 
  1019 * Locale interpretation propagates mixins along the locale hierarchy.
  1020 The currently only available mixins are the equations used to map
  1021 local definitions to terms of the target domain of an interpretation.
  1022 
  1023 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1024 loc" to print all interpretations of locale "loc" in the theory.
  1025 Interpretations in proofs are not shown.
  1026 
  1027 * Thoroughly revised locales tutorial.  New section on conditional
  1028 interpretation.
  1029 
  1030 * On instantiation of classes, remaining undefined class parameters
  1031 are formally declared.  INCOMPATIBILITY.
  1032 
  1033 
  1034 *** Document preparation ***
  1035 
  1036 * New generalized style concept for printing terms: @{foo (style) ...}
  1037 instead of @{foo_style style ...}  (old form is still retained for
  1038 backward compatibility).  Styles can be also applied for
  1039 antiquotations prop, term_type and typeof.
  1040 
  1041 
  1042 *** HOL ***
  1043 
  1044 * New proof method "smt" for a combination of first-order logic with
  1045 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1046 fixed-size bitvectors; there is also basic support for higher-order
  1047 features (esp. lambda abstractions).  It is an incomplete decision
  1048 procedure based on external SMT solvers using the oracle mechanism;
  1049 for the SMT solver Z3, this method is proof-producing.  Certificates
  1050 are provided to avoid calling the external solvers solely for
  1051 re-checking proofs.  Due to a remote SMT service there is no need for
  1052 installing SMT solvers locally.  See src/HOL/SMT.
  1053 
  1054 * New commands to load and prove verification conditions generated by
  1055 the Boogie program verifier or derived systems (e.g. the Verifying C
  1056 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1057 
  1058 * New counterexample generator tool 'nitpick' based on the Kodkod
  1059 relational model finder.  See src/HOL/Tools/Nitpick and
  1060 src/HOL/Nitpick_Examples.
  1061 
  1062 * New commands 'code_pred' and 'values' to invoke the predicate
  1063 compiler and to enumerate values of inductive predicates.
  1064 
  1065 * A tabled implementation of the reflexive transitive closure.
  1066 
  1067 * New implementation of quickcheck uses generic code generator;
  1068 default generators are provided for all suitable HOL types, records
  1069 and datatypes.  Old quickcheck can be re-activated importing theory
  1070 Library/SML_Quickcheck.
  1071 
  1072 * New testing tool Mirabelle for automated proof tools.  Applies
  1073 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1074 every proof step in a theory.  To be used in batch mode via the
  1075 "mirabelle" utility.
  1076 
  1077 * New proof method "sos" (sum of squares) for nonlinear real
  1078 arithmetic (originally due to John Harison). It requires theory
  1079 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1080 works well in practice on quantifier-free real arithmetic with +, -,
  1081 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1082 inequalities between polynomials.  It makes use of external
  1083 semidefinite programming solvers.  Method "sos" generates a
  1084 certificate that can be pasted into the proof thus avoiding the need
  1085 to call an external tool every time the proof is checked.  See
  1086 src/HOL/Library/Sum_Of_Squares.
  1087 
  1088 * New method "linarith" invokes existing linear arithmetic decision
  1089 procedure only.
  1090 
  1091 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1092 
  1093 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1094 Causes full type information to be output to the ATPs.  This slows
  1095 ATPs down considerably but eliminates a source of unsound "proofs"
  1096 that fail later.
  1097 
  1098 * New method "metisFT": A version of metis that uses full type
  1099 information in order to avoid failures of proof reconstruction.
  1100 
  1101 * New evaluator "approximate" approximates an real valued term using
  1102 the same method as the approximation method.
  1103 
  1104 * Method "approximate" now supports arithmetic expressions as
  1105 boundaries of intervals and implements interval splitting and Taylor
  1106 series expansion.
  1107 
  1108 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1109 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1110 
  1111 * New theory SupInf of the supremum and infimum operators for sets of
  1112 reals.
  1113 
  1114 * New theory Probability, which contains a development of measure
  1115 theory, eventually leading to Lebesgue integration and probability.
  1116 
  1117 * Extended Multivariate Analysis to include derivation and Brouwer's
  1118 fixpoint theorem.
  1119 
  1120 * Reorganization of number theory, INCOMPATIBILITY:
  1121   - new number theory development for nat and int, in theories Divides
  1122     and GCD as well as in new session Number_Theory
  1123   - some constants and facts now suffixed with _nat and _int
  1124     accordingly
  1125   - former session NumberTheory now named Old_Number_Theory, including
  1126     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1127   - moved theory Pocklington from src/HOL/Library to
  1128     src/HOL/Old_Number_Theory
  1129 
  1130 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1131 lcm of finite and infinite sets. It is shown that they form a complete
  1132 lattice.
  1133 
  1134 * Class semiring_div requires superclass no_zero_divisors and proof of
  1135 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1136 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1137 generalized to class semiring_div, subsuming former theorems
  1138 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1139 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1140 INCOMPATIBILITY.
  1141 
  1142 * Refinements to lattice classes and sets:
  1143   - less default intro/elim rules in locale variant, more default
  1144     intro/elim rules in class variant: more uniformity
  1145   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1146     le_inf_iff
  1147   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1148     sup_aci)
  1149   - renamed ACI to inf_sup_aci
  1150   - new class "boolean_algebra"
  1151   - class "complete_lattice" moved to separate theory
  1152     "Complete_Lattice"; corresponding constants (and abbreviations)
  1153     renamed and with authentic syntax:
  1154     Set.Inf ~>    Complete_Lattice.Inf
  1155     Set.Sup ~>    Complete_Lattice.Sup
  1156     Set.INFI ~>   Complete_Lattice.INFI
  1157     Set.SUPR ~>   Complete_Lattice.SUPR
  1158     Set.Inter ~>  Complete_Lattice.Inter
  1159     Set.Union ~>  Complete_Lattice.Union
  1160     Set.INTER ~>  Complete_Lattice.INTER
  1161     Set.UNION ~>  Complete_Lattice.UNION
  1162   - authentic syntax for
  1163     Set.Pow
  1164     Set.image
  1165   - mere abbreviations:
  1166     Set.empty               (for bot)
  1167     Set.UNIV                (for top)
  1168     Set.inter               (for inf, formerly Set.Int)
  1169     Set.union               (for sup, formerly Set.Un)
  1170     Complete_Lattice.Inter  (for Inf)
  1171     Complete_Lattice.Union  (for Sup)
  1172     Complete_Lattice.INTER  (for INFI)
  1173     Complete_Lattice.UNION  (for SUPR)
  1174   - object-logic definitions as far as appropriate
  1175 
  1176 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1177 Un_subset_iff are explicitly deleted as default simp rules; then also
  1178 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1179 deleted to achieve the desired effect.
  1180 
  1181 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1182 rules by default any longer; the same applies to min_max.inf_absorb1
  1183 etc.  INCOMPATIBILITY.
  1184 
  1185 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1186 pred_set_conv by default.  INCOMPATIBILITY.
  1187 
  1188 * Power operations on relations and functions are now one dedicated
  1189 constant "compow" with infix syntax "^^".  Power operation on
  1190 multiplicative monoids retains syntax "^" and is now defined generic
  1191 in class power.  INCOMPATIBILITY.
  1192 
  1193 * Relation composition "R O S" now has a more standard argument order:
  1194 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1195 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1196 break, since the O_assoc rule was not rewritten like this.  Fix using
  1197 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1198 
  1199 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1200 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1201 INCOMPATIBILITY.
  1202 
  1203 * Most rules produced by inductive and datatype package have mandatory
  1204 prefixes.  INCOMPATIBILITY.
  1205 
  1206 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1207 the attribute of the same name.  Each of the theorems in the list
  1208 DERIV_intros assumes composition with an additional function and
  1209 matches a variable to the derivative, which has to be solved by the
  1210 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1211 of most elementary terms.  Former Maclauren.DERIV_tac and
  1212 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1213 INCOMPATIBILITY.
  1214 
  1215 * Code generator attributes follow the usual underscore convention:
  1216     code_unfold     replaces    code unfold
  1217     code_post       replaces    code post
  1218     etc.
  1219   INCOMPATIBILITY.
  1220 
  1221 * Renamed methods:
  1222     sizechange -> size_change
  1223     induct_scheme -> induction_schema
  1224   INCOMPATIBILITY.
  1225 
  1226 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1227 INCOMPATIBILITY, use "undefined" directly.
  1228 
  1229 * Renamed theorems:
  1230     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1231     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1232     Suc_plus1 -> Suc_eq_plus1
  1233     *anti_sym -> *antisym*
  1234     vector_less_eq_def -> vector_le_def
  1235   INCOMPATIBILITY.
  1236 
  1237 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1238 INCOMPATIBILITY.
  1239 
  1240 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1241 INCOMPATIBILITY.
  1242 
  1243 
  1244 *** HOLCF ***
  1245 
  1246 * Theory Representable defines a class "rep" of domains that are
  1247 representable (via an ep-pair) in the universal domain type "udom".
  1248 Instances are provided for all type constructors defined in HOLCF.
  1249 
  1250 * The 'new_domain' command is a purely definitional version of the
  1251 domain package, for representable domains.  Syntax is identical to the
  1252 old domain package.  The 'new_domain' package also supports indirect
  1253 recursion using previously-defined type constructors.  See
  1254 src/HOLCF/ex/New_Domain.thy for examples.
  1255 
  1256 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1257 on the left-hand side of an equation, and then performs
  1258 simplification.  Rewriting is done using rules declared with the
  1259 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1260 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1261 
  1262 * The pattern-match compiler in 'fixrec' can now handle constructors
  1263 with HOL function types.  Pattern-match combinators for the Pair
  1264 constructor are pre-configured.
  1265 
  1266 * The 'fixrec' package now produces better fixed-point induction rules
  1267 for mutually-recursive definitions:  Induction rules have conclusions
  1268 of the form "P foo bar" instead of "P <foo, bar>".
  1269 
  1270 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1271 been renamed to "below".  The name "below" now replaces "less" in many
  1272 theorem names.  (Legacy theorem names using "less" are still supported
  1273 as well.)
  1274 
  1275 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1276 patterns can be used to generate strictness rules, or to make
  1277 functions more strict (much like the bang-patterns supported by the
  1278 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1279 examples.
  1280 
  1281 
  1282 *** ML ***
  1283 
  1284 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1285 errors and run-time exceptions, including detailed source positions.
  1286 
  1287 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1288 identified entries, with some additional information such as source
  1289 position, logical grouping etc.
  1290 
  1291 * Theory and context data is now introduced by the simplified and
  1292 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1293 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1294 copy operation) is still available for some time.
  1295 
  1296 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1297 provides a high-level programming interface to synchronized state
  1298 variables with atomic update.  This works via pure function
  1299 application within a critical section -- its runtime should be as
  1300 short as possible; beware of deadlocks if critical code is nested,
  1301 either directly or indirectly via other synchronized variables!
  1302 
  1303 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1304 wraps raw ML references, explicitly indicating their non-thread-safe
  1305 behaviour.  The Isar toplevel keeps this structure open, to
  1306 accommodate Proof General as well as quick and dirty interactive
  1307 experiments with references.
  1308 
  1309 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1310 parallel tactical reasoning.
  1311 
  1312 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1313 are similar to SUBPROOF, but are slightly more flexible: only the
  1314 specified parts of the subgoal are imported into the context, and the
  1315 body tactic may introduce new subgoals and schematic variables.
  1316 
  1317 * Old tactical METAHYPS, which does not observe the proof context, has
  1318 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1319 or Subgoal.FOCUS etc.
  1320 
  1321 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1322 functors have their own ML name space there is no point to mark them
  1323 separately.)  Minor INCOMPATIBILITY.
  1324 
  1325 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1326 
  1327 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1328 INCOMPATIBILITY.
  1329 
  1330 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1331 mode, which avoids critical setmp.
  1332 
  1333 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1334 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1335 Attrib/Method.setup introduced in Isabelle2009.
  1336 
  1337 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1338 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1339 last resort.  INCOMPATIBILITY.
  1340 
  1341 * Display.pretty_thm now requires a proper context (cf. former
  1342 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1343 or even Display.pretty_thm_without_context as last resort.
  1344 INCOMPATIBILITY.
  1345 
  1346 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1347 Syntax.pretty_typ/term directly, preferably with proper context
  1348 instead of global theory.
  1349 
  1350 
  1351 *** System ***
  1352 
  1353 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1354 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1355 usedir option -q.
  1356 
  1357 * Support for additional "Isabelle components" via etc/components, see
  1358 also the system manual.
  1359 
  1360 * The isabelle makeall tool now operates on all components with
  1361 IsaMakefile, not just hardwired "logics".
  1362 
  1363 * Removed "compress" option from isabelle-process and isabelle usedir;
  1364 this is always enabled.
  1365 
  1366 * Discontinued support for Poly/ML 4.x versions.
  1367 
  1368 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  1369 on a given logic image.  This requires the lighttpd webserver and is
  1370 currently supported on Linux only.
  1371 
  1372 
  1373 
  1374 New in Isabelle2009 (April 2009)
  1375 --------------------------------
  1376 
  1377 *** General ***
  1378 
  1379 * Simplified main Isabelle executables, with less surprises on
  1380 case-insensitive file-systems (such as Mac OS).
  1381 
  1382   - The main Isabelle tool wrapper is now called "isabelle" instead of
  1383     "isatool."
  1384 
  1385   - The former "isabelle" alias for "isabelle-process" has been
  1386     removed (should rarely occur to regular users).
  1387 
  1388   - The former "isabelle-interface" and its alias "Isabelle" have been
  1389     removed (interfaces are now regular Isabelle tools).
  1390 
  1391 Within scripts and make files, the Isabelle environment variables
  1392 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  1393 respectively.  (The latter are still available as legacy feature.)
  1394 
  1395 The old isabelle-interface wrapper could react in confusing ways if
  1396 the interface was uninstalled or changed otherwise.  Individual
  1397 interface tool configuration is now more explicit, see also the
  1398 Isabelle system manual.  In particular, Proof General is now available
  1399 via "isabelle emacs".
  1400 
  1401 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  1402 purge installed copies of Isabelle executables and re-run "isabelle
  1403 install -p ...", or use symlinks.
  1404 
  1405 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  1406 old ~/isabelle, which was slightly non-standard and apt to cause
  1407 surprises on case-insensitive file-systems (such as Mac OS).
  1408 
  1409 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  1410 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  1411 care is required when using older releases of Isabelle.  Note that
  1412 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  1413 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  1414 
  1415 * Proofs of fully specified statements are run in parallel on
  1416 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  1417 a regular 4-core machine, if the initial heap space is made reasonably
  1418 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  1419 
  1420 * The main reference manuals ("isar-ref", "implementation", and
  1421 "system") have been updated and extended.  Formally checked references
  1422 as hyperlinks are now available uniformly.
  1423 
  1424 
  1425 *** Pure ***
  1426 
  1427 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  1428 respects.  The most important changes are listed below.  See the
  1429 Tutorial on Locales ("locales" manual) for details.
  1430 
  1431 - In locale expressions, instantiation replaces renaming.  Parameters
  1432 must be declared in a for clause.  To aid compatibility with previous
  1433 parameter inheritance, in locale declarations, parameters that are not
  1434 'touched' (instantiation position "_" or omitted) are implicitly added
  1435 with their syntax at the beginning of the for clause.
  1436 
  1437 - Syntax from abbreviations and definitions in locales is available in
  1438 locale expressions and context elements.  The latter is particularly
  1439 useful in locale declarations.
  1440 
  1441 - More flexible mechanisms to qualify names generated by locale
  1442 expressions.  Qualifiers (prefixes) may be specified in locale
  1443 expressions, and can be marked as mandatory (syntax: "name!:") or
  1444 optional (syntax "name?:").  The default depends for plain "name:"
  1445 depends on the situation where a locale expression is used: in
  1446 commands 'locale' and 'sublocale' prefixes are optional, in
  1447 'interpretation' and 'interpret' prefixes are mandatory.  The old
  1448 implicit qualifiers derived from the parameter names of a locale are
  1449 no longer generated.
  1450 
  1451 - Command "sublocale l < e" replaces "interpretation l < e".  The
  1452 instantiation clause in "interpretation" and "interpret" (square
  1453 brackets) is no longer available.  Use locale expressions.
  1454 
  1455 - When converting proof scripts, mandatory qualifiers in
  1456 'interpretation' and 'interpret' should be retained by default, even
  1457 if this is an INCOMPATIBILITY compared to former behavior.  In the
  1458 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  1459 in locale expressions range over a single locale instance only.
  1460 
  1461 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  1462 In existing theorem specifications replace the includes element by the
  1463 respective context elements of the included locale, omitting those
  1464 that are already present in the theorem specification.  Multiple
  1465 assume elements of a locale should be replaced by a single one
  1466 involving the locale predicate.  In the proof body, declarations (most
  1467 notably theorems) may be regained by interpreting the respective
  1468 locales in the proof context as required (command "interpret").
  1469 
  1470 If using "includes" in replacement of a target solely because the
  1471 parameter types in the theorem are not as general as in the target,
  1472 consider declaring a new locale with additional type constraints on
  1473 the parameters (context element "constrains").
  1474 
  1475 - Discontinued "locale (open)".  INCOMPATIBILITY.
  1476 
  1477 - Locale interpretation commands no longer attempt to simplify goal.
  1478 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  1479 methods intro_locales and unfold_locales to clarify.
  1480 
  1481 - Locale interpretation commands no longer accept interpretation
  1482 attributes.  INCOMPATIBILITY.
  1483 
  1484 * Class declaration: so-called "base sort" must not be given in import
  1485 list any longer, but is inferred from the specification.  Particularly
  1486 in HOL, write
  1487 
  1488     class foo = ...
  1489 
  1490 instead of
  1491 
  1492     class foo = type + ...
  1493 
  1494 * Class target: global versions of theorems stemming do not carry a
  1495 parameter prefix any longer.  INCOMPATIBILITY.
  1496 
  1497 * Class 'instance' command no longer accepts attached definitions.
  1498 INCOMPATIBILITY, use proper 'instantiation' target instead.
  1499 
  1500 * Recovered hiding of consts, which was accidentally broken in
  1501 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  1502 makes c inaccessible; consider using ``hide (open) const c'' instead.
  1503 
  1504 * Slightly more coherent Pure syntax, with updated documentation in
  1505 isar-ref manual.  Removed locales meta_term_syntax and
  1506 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  1507 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  1508 directly in regular applications.
  1509 
  1510 * There is a new syntactic category "float_const" for signed decimal
  1511 fractions (e.g. 123.45 or -123.45).
  1512 
  1513 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  1514 interface with 'setup' command instead.
  1515 
  1516 * Command 'local_setup' is similar to 'setup', but operates on a local
  1517 theory context.
  1518 
  1519 * The 'axiomatization' command now only works within a global theory
  1520 context.  INCOMPATIBILITY.
  1521 
  1522 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  1523 hypotheses.  Sorts required in the course of reasoning need to be
  1524 covered by the constraints in the initial statement, completed by the
  1525 type instance information of the background theory.  Non-trivial sort
  1526 hypotheses, which rarely occur in practice, may be specified via
  1527 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  1528 
  1529   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  1530 
  1531 The result contains an implicit sort hypotheses as before --
  1532 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  1533 normalization.
  1534 
  1535 * Generalized Isar history, with support for linear undo, direct state
  1536 addressing etc.
  1537 
  1538 * Changed defaults for unify configuration options:
  1539 
  1540   unify_trace_bound = 50 (formerly 25)
  1541   unify_search_bound = 60 (formerly 30)
  1542 
  1543 * Different bookkeeping for code equations (INCOMPATIBILITY):
  1544 
  1545   a) On theory merge, the last set of code equations for a particular
  1546      constant is taken (in accordance with the policy applied by other
  1547      parts of the code generator framework).
  1548 
  1549   b) Code equations stemming from explicit declarations (e.g. code
  1550      attribute) gain priority over default code equations stemming
  1551      from definition, primrec, fun etc.
  1552 
  1553 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  1554 
  1555 * Unified theorem tables for both code generators.  Thus [code
  1556 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  1557 
  1558 * Command 'find_consts' searches for constants based on type and name
  1559 patterns, e.g.
  1560 
  1561     find_consts "_ => bool"
  1562 
  1563 By default, matching is against subtypes, but it may be restricted to
  1564 the whole type.  Searching by name is possible.  Multiple queries are
  1565 conjunctive and queries may be negated by prefixing them with a
  1566 hyphen:
  1567 
  1568     find_consts strict: "_ => bool" name: "Int" -"int => int"
  1569 
  1570 * New 'find_theorems' criterion "solves" matches theorems that
  1571 directly solve the current goal (modulo higher-order unification).
  1572 
  1573 * Auto solve feature for main theorem statements: whenever a new goal
  1574 is stated, "find_theorems solves" is called; any theorems that could
  1575 solve the lemma directly are listed as part of the goal state.
  1576 Cf. associated options in Proof General Isabelle settings menu,
  1577 enabled by default, with reasonable timeout for pathological cases of
  1578 higher-order unification.
  1579 
  1580 
  1581 *** Document preparation ***
  1582 
  1583 * Antiquotation @{lemma} now imitates a regular terminal proof,
  1584 demanding keyword 'by' and supporting the full method expression
  1585 syntax just like the Isar command 'by'.
  1586 
  1587 
  1588 *** HOL ***
  1589 
  1590 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  1591 points Main and Complex_Main remain as before.
  1592 
  1593 * Logic image HOL-Plain provides a minimal HOL with the most important
  1594 tools available (inductive, datatype, primrec, ...).  This facilitates
  1595 experimentation and tool development.  Note that user applications
  1596 (and library theories) should never refer to anything below theory
  1597 Main, as before.
  1598 
  1599 * Logic image HOL-Main stops at theory Main, and thus facilitates
  1600 experimentation due to shorter build times.
  1601 
  1602 * Logic image HOL-NSA contains theories of nonstandard analysis which
  1603 were previously part of former HOL-Complex.  Entry point Hyperreal
  1604 remains valid, but theories formerly using Complex_Main should now use
  1605 new entry point Hypercomplex.
  1606 
  1607 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  1608 Posix processes.  Avoids potentially expensive forking of the ML
  1609 process.  New thread-based implementation also works on non-Unix
  1610 platforms (Cygwin).  Provers are no longer hardwired, but defined
  1611 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  1612 commands are covered in the isar-ref manual.
  1613 
  1614 * Wrapper scripts for remote SystemOnTPTP service allows to use
  1615 sledgehammer without local ATP installation (Vampire etc.). Other
  1616 provers may be included via suitable ML wrappers, see also
  1617 src/HOL/ATP_Linkup.thy.
  1618 
  1619 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  1620 menu.
  1621 
  1622 * The metis method no longer fails because the theorem is too trivial
  1623 (contains the empty clause).
  1624 
  1625 * The metis method now fails in the usual manner, rather than raising
  1626 an exception, if it determines that it cannot prove the theorem.
  1627 
  1628 * Method "coherent" implements a prover for coherent logic (see also
  1629 src/Tools/coherent.ML).
  1630 
  1631 * Constants "undefined" and "default" replace "arbitrary".  Usually
  1632 "undefined" is the right choice to replace "arbitrary", though
  1633 logically there is no difference.  INCOMPATIBILITY.
  1634 
  1635 * Command "value" now integrates different evaluation mechanisms.  The
  1636 result of the first successful evaluation mechanism is printed.  In
  1637 square brackets a particular named evaluation mechanisms may be
  1638 specified (currently, [SML], [code] or [nbe]).  See further
  1639 src/HOL/ex/Eval_Examples.thy.
  1640 
  1641 * Normalization by evaluation now allows non-leftlinear equations.
  1642 Declare with attribute [code nbe].
  1643 
  1644 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  1645 as the structured Isar versions "cases" and "induct", cf. the
  1646 corresponding "cases" and "induct" attributes.  Mutual induction rules
  1647 are now presented as a list of individual projections
  1648 (e.g. foo_bar.inducts for types foo and bar); the old format with
  1649 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  1650 rare situations a different rule is selected --- notably nested tuple
  1651 elimination instead of former prod.exhaust: use explicit (case_tac t
  1652 rule: prod.exhaust) here.
  1653 
  1654 * Attributes "cases", "induct", "coinduct" support "del" option.
  1655 
  1656 * Removed fact "case_split_thm", which duplicates "case_split".
  1657 
  1658 * The option datatype has been moved to a new theory Option.  Renamed
  1659 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  1660 
  1661 * New predicate "strict_mono" classifies strict functions on partial
  1662 orders.  With strict functions on linear orders, reasoning about
  1663 (in)equalities is facilitated by theorems "strict_mono_eq",
  1664 "strict_mono_less_eq" and "strict_mono_less".
  1665 
  1666 * Some set operations are now proper qualified constants with
  1667 authentic syntax.  INCOMPATIBILITY:
  1668 
  1669     op Int ~>   Set.Int
  1670     op Un ~>    Set.Un
  1671     INTER ~>    Set.INTER
  1672     UNION ~>    Set.UNION
  1673     Inter ~>    Set.Inter
  1674     Union ~>    Set.Union
  1675     {} ~>       Set.empty
  1676     UNIV ~>     Set.UNIV
  1677 
  1678 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  1679 theory Set.
  1680 
  1681 * Auxiliary class "itself" has disappeared -- classes without any
  1682 parameter are treated as expected by the 'class' command.
  1683 
  1684 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  1685 
  1686 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  1687 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  1688 
  1689 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  1690 method "approximation".  It proves formulas on real values by using
  1691 interval arithmetic.  In the formulas are also the transcendental
  1692 functions sin, cos, tan, atan, ln, exp and the constant pi are
  1693 allowed. For examples see
  1694 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  1695 
  1696 * Theory "Reflection" now resides in HOL/Library.
  1697 
  1698 * Entry point to Word library now simply named "Word".
  1699 INCOMPATIBILITY.
  1700 
  1701 * Made source layout more coherent with logical distribution
  1702 structure:
  1703 
  1704     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  1705     src/HOL/Library/Code_Message.thy ~> src/HOL/
  1706     src/HOL/Library/GCD.thy ~> src/HOL/
  1707     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  1708     src/HOL/Library/Parity.thy ~> src/HOL/
  1709     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  1710     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  1711     src/HOL/Real/Lubs.thy ~> src/HOL/
  1712     src/HOL/Real/PReal.thy ~> src/HOL/
  1713     src/HOL/Real/Rational.thy ~> src/HOL/
  1714     src/HOL/Real/RComplete.thy ~> src/HOL/
  1715     src/HOL/Real/RealDef.thy ~> src/HOL/
  1716     src/HOL/Real/RealPow.thy ~> src/HOL/
  1717     src/HOL/Real/Real.thy ~> src/HOL/
  1718     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  1719     src/HOL/Complex/Complex.thy ~> src/HOL/
  1720     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  1721     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  1722     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  1723     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  1724     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  1725     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  1726     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  1727     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  1728     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  1729     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  1730     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  1731     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  1732     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  1733     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  1734     src/HOL/Real/Float ~> src/HOL/Library/
  1735     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  1736     src/HOL/Real/RealVector.thy ~> src/HOL/
  1737 
  1738     src/HOL/arith_data.ML ~> src/HOL/Tools
  1739     src/HOL/hologic.ML ~> src/HOL/Tools
  1740     src/HOL/simpdata.ML ~> src/HOL/Tools
  1741     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  1742     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  1743     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  1744     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  1745     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  1746     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  1747     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  1748 
  1749     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  1750     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  1751     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  1752     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  1753     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  1754     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  1755 
  1756 * If methods "eval" and "evaluation" encounter a structured proof
  1757 state with !!/==>, only the conclusion is evaluated to True (if
  1758 possible), avoiding strange error messages.
  1759 
  1760 * Method "sizechange" automates termination proofs using (a
  1761 modification of) the size-change principle.  Requires SAT solver.  See
  1762 src/HOL/ex/Termination.thy for examples.
  1763 
  1764 * Simplifier: simproc for let expressions now unfolds if bound
  1765 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  1766 
  1767 * Method "arith": Linear arithmetic now ignores all inequalities when
  1768 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  1769 
  1770 * New attribute "arith" for facts that should always be used
  1771 automatically by arithmetic. It is intended to be used locally in
  1772 proofs, e.g.
  1773 
  1774   assumes [arith]: "x > 0"
  1775 
  1776 Global usage is discouraged because of possible performance impact.
  1777 
  1778 * New classes "top" and "bot" with corresponding operations "top" and
  1779 "bot" in theory Orderings; instantiation of class "complete_lattice"
  1780 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  1781 
  1782 * Changed definition lemma "less_fun_def" in order to provide an
  1783 instance for preorders on functions; use lemma "less_le" instead.
  1784 INCOMPATIBILITY.
  1785 
  1786 * Theory Orderings: class "wellorder" moved here, with explicit
  1787 induction rule "less_induct" as assumption.  For instantiation of
  1788 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  1789 INCOMPATIBILITY.
  1790 
  1791 * Theory Orderings: added class "preorder" as superclass of "order".
  1792 INCOMPATIBILITY: Instantiation proofs for order, linorder
  1793 etc. slightly changed.  Some theorems named order_class.* now named
  1794 preorder_class.*.
  1795 
  1796 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  1797 "diag" to "Id_on".
  1798 
  1799 * Theory Finite_Set: added a new fold combinator of type
  1800 
  1801   ('a => 'b => 'b) => 'b => 'a set => 'b
  1802 
  1803 Occasionally this is more convenient than the old fold combinator
  1804 which is now defined in terms of the new one and renamed to
  1805 fold_image.
  1806 
  1807 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  1808 and "ring_simps" have been replaced by "algebra_simps" (which can be
  1809 extended with further lemmas!).  At the moment both still exist but
  1810 the former will disappear at some point.
  1811 
  1812 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  1813 class recpower.  Type-specific simp rules for various recpower types
  1814 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  1815 
  1816 rat_power_0    -> power_0
  1817 rat_power_Suc  -> power_Suc
  1818 realpow_0      -> power_0
  1819 realpow_Suc    -> power_Suc
  1820 complexpow_0   -> power_0
  1821 complexpow_Suc -> power_Suc
  1822 power_poly_0   -> power_0
  1823 power_poly_Suc -> power_Suc
  1824 
  1825 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  1826 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  1827 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  1828 of lemmas from Divides has been generalized from nat to class
  1829 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  1830 renames resulting from duplicate elimination:
  1831 
  1832     dvd_def_mod ~>          dvd_eq_mod_eq_0
  1833     zero_dvd_iff ~>         dvd_0_left_iff
  1834     dvd_0 ~>                dvd_0_right
  1835     DIVISION_BY_ZERO_DIV ~> div_by_0
  1836     DIVISION_BY_ZERO_MOD ~> mod_by_0
  1837     mult_div ~>             div_mult_self2_is_id
  1838     mult_mod ~>             mod_mult_self2_is_0
  1839 
  1840 * Theory IntDiv: removed many lemmas that are instances of class-based
  1841 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  1842 rename old lemmas as follows:
  1843 
  1844 dvd_diff               -> nat_dvd_diff
  1845 dvd_zminus_iff         -> dvd_minus_iff
  1846 mod_add1_eq            -> mod_add_eq
  1847 mod_mult1_eq           -> mod_mult_right_eq
  1848 mod_mult1_eq'          -> mod_mult_left_eq
  1849 mod_mult_distrib_mod   -> mod_mult_eq
  1850 nat_mod_add_left_eq    -> mod_add_left_eq
  1851 nat_mod_add_right_eq   -> mod_add_right_eq
  1852 nat_mod_div_trivial    -> mod_div_trivial
  1853 nat_mod_mod_trivial    -> mod_mod_trivial
  1854 zdiv_zadd_self1        -> div_add_self1
  1855 zdiv_zadd_self2        -> div_add_self2
  1856 zdiv_zmult_self1       -> div_mult_self2_is_id
  1857 zdiv_zmult_self2       -> div_mult_self1_is_id
  1858 zdvd_triv_left         -> dvd_triv_left
  1859 zdvd_triv_right        -> dvd_triv_right
  1860 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  1861 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  1862 zmod_zadd_left_eq      -> mod_add_left_eq
  1863 zmod_zadd_right_eq     -> mod_add_right_eq
  1864 zmod_zadd_self1        -> mod_add_self1
  1865 zmod_zadd_self2        -> mod_add_self2
  1866 zmod_zadd1_eq          -> mod_add_eq
  1867 zmod_zdiff1_eq         -> mod_diff_eq
  1868 zmod_zdvd_zmod         -> mod_mod_cancel
  1869 zmod_zmod_cancel       -> mod_mod_cancel
  1870 zmod_zmult_self1       -> mod_mult_self2_is_0
  1871 zmod_zmult_self2       -> mod_mult_self1_is_0
  1872 zmod_1                 -> mod_by_1
  1873 zdiv_1                 -> div_by_1
  1874 zdvd_abs1              -> abs_dvd_iff
  1875 zdvd_abs2              -> dvd_abs_iff
  1876 zdvd_refl              -> dvd_refl
  1877 zdvd_trans             -> dvd_trans
  1878 zdvd_zadd              -> dvd_add
  1879 zdvd_zdiff             -> dvd_diff
  1880 zdvd_zminus_iff        -> dvd_minus_iff
  1881 zdvd_zminus2_iff       -> minus_dvd_iff
  1882 zdvd_zmultD            -> dvd_mult_right
  1883 zdvd_zmultD2           -> dvd_mult_left
  1884 zdvd_zmult_mono        -> mult_dvd_mono
  1885 zdvd_0_right           -> dvd_0_right
  1886 zdvd_0_left            -> dvd_0_left_iff
  1887 zdvd_1_left            -> one_dvd
  1888 zminus_dvd_iff         -> minus_dvd_iff
  1889 
  1890 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  1891 
  1892 * The real numbers offer decimal input syntax: 12.34 is translated
  1893 into 1234/10^2. This translation is not reversed upon output.
  1894 
  1895 * Theory Library/Polynomial defines an abstract type 'a poly of
  1896 univariate polynomials with coefficients of type 'a.  In addition to
  1897 the standard ring operations, it also supports div and mod.  Code
  1898 generation is also supported, using list-style constructors.
  1899 
  1900 * Theory Library/Inner_Product defines a class of real_inner for real
  1901 inner product spaces, with an overloaded operation inner :: 'a => 'a
  1902 => real.  Class real_inner is a subclass of real_normed_vector from
  1903 theory RealVector.
  1904 
  1905 * Theory Library/Product_Vector provides instances for the product
  1906 type 'a * 'b of several classes from RealVector and Inner_Product.
  1907 Definitions of addition, subtraction, scalar multiplication, norms,
  1908 and inner products are included.
  1909 
  1910 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  1911 addition to the field operations, numerals and case syntax are also
  1912 supported.
  1913 
  1914 * Theory Library/Diagonalize provides constructive version of Cantor's
  1915 first diagonalization argument.
  1916 
  1917 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  1918 zlcm (for int); carried together from various gcd/lcm developements in
  1919 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  1920 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  1921 may recover tupled syntax as follows:
  1922 
  1923     hide (open) const gcd
  1924     abbreviation gcd where
  1925       "gcd == (%(a, b). GCD.gcd a b)"
  1926     notation (output)
  1927       GCD.gcd ("gcd '(_, _')")
  1928 
  1929 The same works for lcm, zgcd, zlcm.
  1930 
  1931 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  1932 instantiations for algebraic structures.  Removed some duplicate
  1933 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  1934 
  1935 * ML antiquotation @{code} takes a constant as argument and generates
  1936 corresponding code in background and inserts name of the corresponding
  1937 resulting ML value/function/datatype constructor binding in place.
  1938 All occurrences of @{code} with a single ML block are generated
  1939 simultaneously.  Provides a generic and safe interface for
  1940 instrumentalizing code generation.  See
  1941 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  1942 In future you ought to refrain from ad-hoc compiling generated SML
  1943 code on the ML toplevel.  Note that (for technical reasons) @{code}
  1944 cannot refer to constants for which user-defined serializations are
  1945 set.  Refer to the corresponding ML counterpart directly in that
  1946 cases.
  1947 
  1948 * Command 'rep_datatype': instead of theorem names the command now
  1949 takes a list of terms denoting the constructors of the type to be
  1950 represented as datatype.  The characteristic theorems have to be
  1951 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  1952 have disappeared in favour of existing ones:
  1953 
  1954     unit_induct                 ~> unit.induct
  1955     prod_induct                 ~> prod.induct
  1956     sum_induct                  ~> sum.induct
  1957     Suc_Suc_eq                  ~> nat.inject
  1958     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  1959 
  1960 
  1961 *** HOL-Algebra ***
  1962 
  1963 * New locales for orders and lattices where the equivalence relation
  1964 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  1965 locales use a record structure with field eq for the equivalence.
  1966 
  1967 * New theory of factorial domains.
  1968 
  1969 * Units_l_inv and Units_r_inv are now simp rules by default.
  1970 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  1971 and/or r_inv will now also require deletion of these lemmas.
  1972 
  1973 * Renamed the following theorems, INCOMPATIBILITY:
  1974 
  1975 UpperD ~> Upper_memD
  1976 LowerD ~> Lower_memD
  1977 least_carrier ~> least_closed
  1978 greatest_carrier ~> greatest_closed
  1979 greatest_Lower_above ~> greatest_Lower_below
  1980 one_zero ~> carrier_one_zero
  1981 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  1982 
  1983 
  1984 *** HOL-Nominal ***
  1985 
  1986 * Nominal datatypes can now contain type-variables.
  1987 
  1988 * Commands 'nominal_inductive' and 'equivariance' work with local
  1989 theory targets.
  1990 
  1991 * Nominal primrec can now works with local theory targets and its
  1992 specification syntax now conforms to the general format as seen in
  1993 'inductive' etc.
  1994 
  1995 * Method "perm_simp" honours the standard simplifier attributes
  1996 (no_asm), (no_asm_use) etc.
  1997 
  1998 * The new predicate #* is defined like freshness, except that on the
  1999 left hand side can be a set or list of atoms.
  2000 
  2001 * Experimental command 'nominal_inductive2' derives strong induction
  2002 principles for inductive definitions.  In contrast to
  2003 'nominal_inductive', which can only deal with a fixed number of
  2004 binders, it can deal with arbitrary expressions standing for sets of
  2005 atoms to be avoided.  The only inductive definition we have at the
  2006 moment that needs this generalisation is the typing rule for Lets in
  2007 the algorithm W:
  2008 
  2009  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2010  -----------------------------------------------------------------
  2011          Gamma |- Let x be t1 in t2 : T2
  2012 
  2013 In this rule one wants to avoid all the binders that are introduced by
  2014 "close Gamma T1".  We are looking for other examples where this
  2015 feature might be useful.  Please let us know.
  2016 
  2017 
  2018 *** HOLCF ***
  2019 
  2020 * Reimplemented the simplification procedure for proving continuity
  2021 subgoals.  The new simproc is extensible; users can declare additional
  2022 continuity introduction rules with the attribute [cont2cont].
  2023 
  2024 * The continuity simproc now uses a different introduction rule for
  2025 solving continuity subgoals on terms with lambda abstractions.  In
  2026 some rare cases the new simproc may fail to solve subgoals that the
  2027 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2028 Potential INCOMPATIBILITY.
  2029 
  2030 * Command 'fixrec': specification syntax now conforms to the general
  2031 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2032 examples.  INCOMPATIBILITY.
  2033 
  2034 
  2035 *** ZF ***
  2036 
  2037 * Proof of Zorn's Lemma for partial orders.
  2038 
  2039 
  2040 *** ML ***
  2041 
  2042 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2043 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2044 depends on multithreading, so timouts will not work before Poly/ML
  2045 5.2.1!
  2046 
  2047 * High-level support for concurrent ML programming, see
  2048 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2049 particularly convenient to organize independent functional
  2050 computations.  The concept of "synchronized variables" provides a
  2051 higher-order interface for components with shared state, avoiding the
  2052 delicate details of mutexes and condition variables.  (Requires
  2053 Poly/ML 5.2.1 or later.)
  2054 
  2055 * ML bindings produced via Isar commands are stored within the Isar
  2056 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2057 become thread-safe and work with undo as expected (concerning
  2058 top-level bindings, not side-effects on global references).
  2059 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2060 compiler at runtime; really global bindings need to be given outside a
  2061 theory.  (Requires Poly/ML 5.2 or later.)
  2062 
  2063 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2064 context.  Top-level ML bindings are stored within the proof context in
  2065 a purely sequential fashion, disregarding the nested proof structure.
  2066 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2067 proof.  (Requires Poly/ML 5.2 or later.)
  2068 
  2069 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2070 and Method.setup, as well as Isar commands 'attribute_setup' and
  2071 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2072 existing code accordingly, or use plain 'setup' together with old
  2073 Method.add_method.
  2074 
  2075 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2076 to 'a -> thm, while results are always tagged with an authentic oracle
  2077 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2078 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2079 accordingly.  Note that extra performance may be gained by producing
  2080 the cterm carefully, avoiding slow Thm.cterm_of.
  2081 
  2082 * Simplified interface for defining document antiquotations via
  2083 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2084 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2085 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2086 examples.
  2087 
  2088 * More systematic treatment of long names, abstract name bindings, and
  2089 name space operations.  Basic operations on qualified names have been
  2090 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2091 Long_Name.append.  Old type bstring has been mostly replaced by
  2092 abstract type binding (see structure Binding), which supports precise
  2093 qualification by packages and local theory targets, as well as proper
  2094 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2095 bstring values into Binding.name, or better pass through abstract
  2096 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2097 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2098 
  2099 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2100 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2101 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2102 
  2103 * Disposed old type and term read functions (Sign.read_def_typ,
  2104 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2105 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2106 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2107 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2108 resort for legacy applications.
  2109 
  2110 * Disposed old declarations, tactics, tactic combinators that refer to
  2111 the simpset or claset of an implicit theory (such as Addsimps,
  2112 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2113 embedded ML text, or local_simpset_of with a proper context passed as
  2114 explicit runtime argument.
  2115 
  2116 * Rules and tactics that read instantiations (read_instantiate,
  2117 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2118 context, which is required for parsing and type-checking.  Moreover,
  2119 the variables are specified as plain indexnames, not string encodings
  2120 thereof.  INCOMPATIBILITY.
  2121 
  2122 * Generic Toplevel.add_hook interface allows to analyze the result of
  2123 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2124 for theorem dependency output of transactions resulting in a new
  2125 theory state.
  2126 
  2127 * ML antiquotations: block-structured compilation context indicated by
  2128 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2129 
  2130   @{binding name}                         - basic name binding
  2131   @{let ?pat = term}                      - term abbreviation (HO matching)
  2132   @{note name = fact}                     - fact abbreviation
  2133   @{thm fact}                             - singleton fact (with attributes)
  2134   @{thms fact}                            - general fact (with attributes)
  2135   @{lemma prop by method}                 - singleton goal
  2136   @{lemma prop by meth1 meth2}            - singleton goal
  2137   @{lemma prop1 ... propN by method}      - general goal
  2138   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2139   @{lemma (open) ...}                     - open derivation
  2140 
  2141 
  2142 *** System ***
  2143 
  2144 * The Isabelle "emacs" tool provides a specific interface to invoke
  2145 Proof General / Emacs, with more explicit failure if that is not
  2146 installed (the old isabelle-interface script silently falls back on
  2147 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2148 installation location of the Proof General distribution.
  2149 
  2150 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2151 the Isabelle process into a JVM/Scala application.  See
  2152 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2153 process wrapper has been discontinued.)
  2154 
  2155 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2156 
  2157 * Various status messages (with exact source position information) are
  2158 emitted, if proper markup print mode is enabled.  This allows
  2159 user-interface components to provide detailed feedback on internal
  2160 prover operations.
  2161 
  2162 
  2163 
  2164 New in Isabelle2008 (June 2008)
  2165 -------------------------------
  2166 
  2167 *** General ***
  2168 
  2169 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2170 and updated, with formally checked references as hyperlinks.
  2171 
  2172 * Theory loader: use_thy (and similar operations) no longer set the
  2173 implicit ML context, which was occasionally hard to predict and in
  2174 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2175 provides a proper context already.
  2176 
  2177 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2178 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2179 'use' within a theory file will do the job.
  2180 
  2181 * Name space merge now observes canonical order, i.e. the second space
  2182 is inserted into the first one, while existing entries in the first
  2183 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2184 swap theory imports.
  2185 
  2186 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2187 INCOMPATIBILITY in identifier syntax etc.
  2188 
  2189 * Outer syntax: string tokens no longer admit escaped white space,
  2190 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2191 white space without escapes.
  2192 
  2193 * Outer syntax: string tokens may contain arbitrary character codes
  2194 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2195 "foo_bar".
  2196 
  2197 
  2198 *** Pure ***
  2199 
  2200 * Context-dependent token translations.  Default setup reverts locally
  2201 fixed variables, and adds hilite markup for undeclared frees.
  2202 
  2203 * Unused theorems can be found using the new command 'unused_thms'.
  2204 There are three ways of invoking it:
  2205 
  2206 (1) unused_thms
  2207      Only finds unused theorems in the current theory.
  2208 
  2209 (2) unused_thms thy_1 ... thy_n -
  2210      Finds unused theorems in the current theory and all of its ancestors,
  2211      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2212 
  2213 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2214      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2215      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2216      their ancestors.
  2217 
  2218 In order to increase the readability of the list produced by
  2219 unused_thms, theorems that have been created by a particular instance
  2220 of a theory command such as 'inductive' or 'function' are considered
  2221 to belong to the same "group", meaning that if at least one theorem in
  2222 this group is used, the other theorems in the same group are no longer
  2223 reported as unused.  Moreover, if all theorems in the group are
  2224 unused, only one theorem in the group is displayed.
  2225 
  2226 Note that proof objects have to be switched on in order for
  2227 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2228 usually the case when using Proof General with the default settings).
  2229 
  2230 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2231 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2232 duplicate fact bindings, or even accidental fact duplications.  Note
  2233 that tools may maintain dynamically scoped facts systematically, using
  2234 PureThy.add_thms_dynamic.
  2235 
  2236 * Command 'hide' now allows to hide from "fact" name space as well.
  2237 
  2238 * Eliminated destructive theorem database, simpset, claset, and
  2239 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2240 update of theories within ML code.
  2241 
  2242 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2243 INCOMPATIBILITY, object-logics depending on former Pure require
  2244 additional setup PureThy.old_appl_syntax_setup; object-logics
  2245 depending on former CPure need to refer to Pure.
  2246 
  2247 * Commands 'use' and 'ML' are now purely functional, operating on
  2248 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2249 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2250 INCOMPATIBILITY.
  2251 
  2252 * Command 'setup': discontinued implicit version with ML reference.
  2253 
  2254 * Instantiation target allows for simultaneous specification of class
  2255 instance operations together with an instantiation proof.
  2256 Type-checking phase allows to refer to class operations uniformly.
  2257 See src/HOL/Complex/Complex.thy for an Isar example and
  2258 src/HOL/Library/Eval.thy for an ML example.
  2259 
  2260 * Indexing of literal facts: be more serious about including only
  2261 facts from the visible specification/proof context, but not the
  2262 background context (locale etc.).  Affects `prop` notation and method
  2263 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2264 situations.
  2265 
  2266 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2267 "(open)" option, which used to expose internal bound variables to the
  2268 proof text.
  2269 
  2270 * Isar statements: removed obsolete case "rule_context".
  2271 INCOMPATIBILITY, better use explicit fixes/assumes.
  2272 
  2273 * Locale proofs: default proof step now includes 'unfold_locales';
  2274 hence 'proof' without argument may be used to unfold locale
  2275 predicates.
  2276 
  2277 
  2278 *** Document preparation ***
  2279 
  2280 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2281 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2282 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2283 spot); renamed link color from "darkblue" to "linkcolor" (default
  2284 value unchanged, can be redefined via \definecolor); no longer sets
  2285 "a4paper" option (unnecessary or even intrusive).
  2286 
  2287 * Antiquotation @{lemma A method} proves proposition A by the given
  2288 method (either a method name or a method name plus (optional) method
  2289 arguments in parentheses) and prints A just like @{prop A}.
  2290 
  2291 
  2292 *** HOL ***
  2293 
  2294 * New primrec package.  Specification syntax conforms in style to
  2295 definition/function/....  No separate induction rule is provided.  The
  2296 "primrec" command distinguishes old-style and new-style specifications
  2297 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2298 When adjusting theories, beware: constants stemming from new-style
  2299 primrec specifications have authentic syntax.
  2300 
  2301 * Metis prover is now an order of magnitude faster, and also works
  2302 with multithreading.
  2303 
  2304 * Metis: the maximum number of clauses that can be produced from a
  2305 theorem is now given by the attribute max_clauses.  Theorems that
  2306 exceed this number are ignored, with a warning printed.
  2307 
  2308 * Sledgehammer no longer produces structured proofs by default. To
  2309 enable, declare [[sledgehammer_full = true]].  Attributes
  2310 reconstruction_modulus, reconstruction_sorts renamed
  2311 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2312 
  2313 * Method "induct_scheme" derives user-specified induction rules
  2314 from well-founded induction and completeness of patterns. This factors
  2315 out some operations that are done internally by the function package
  2316 and makes them available separately.  See
  2317 src/HOL/ex/Induction_Scheme.thy for examples.
  2318 
  2319 * More flexible generation of measure functions for termination
  2320 proofs: Measure functions can be declared by proving a rule of the
  2321 form "is_measure f" and giving it the [measure_function] attribute.
  2322 The "is_measure" predicate is logically meaningless (always true), and
  2323 just guides the heuristic.  To find suitable measure functions, the
  2324 termination prover sets up the goal "is_measure ?f" of the appropriate
  2325 type and generates all solutions by prolog-style backwards proof using
  2326 the declared rules.
  2327 
  2328 This setup also deals with rules like 
  2329 
  2330   "is_measure f ==> is_measure (list_size f)"
  2331 
  2332 which accommodates nested datatypes that recurse through lists.
  2333 Similar rules are predeclared for products and option types.
  2334 
  2335 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2336 
  2337   INCOMPATIBILITIES:
  2338 
  2339   - Definitions of overloaded constants on sets have to be replaced by
  2340     definitions on => and bool.
  2341 
  2342   - Some definitions of overloaded operators on sets can now be proved
  2343     using the definitions of the operators on => and bool.  Therefore,
  2344     the following theorems have been renamed:
  2345 
  2346       subset_def   -> subset_eq
  2347       psubset_def  -> psubset_eq
  2348       set_diff_def -> set_diff_eq
  2349       Compl_def    -> Compl_eq
  2350       Sup_set_def  -> Sup_set_eq
  2351       Inf_set_def  -> Inf_set_eq
  2352       sup_set_def  -> sup_set_eq
  2353       inf_set_def  -> inf_set_eq
  2354 
  2355   - Due to the incompleteness of the HO unification algorithm, some
  2356     rules such as subst may require manual instantiation, if some of
  2357     the unknowns in the rule is a set.
  2358 
  2359   - Higher order unification and forward proofs:
  2360     The proof pattern
  2361 
  2362       have "P (S::'a set)" <...>
  2363       then have "EX S. P S" ..
  2364 
  2365     no longer works (due to the incompleteness of the HO unification
  2366     algorithm) and must be replaced by the pattern
  2367 
  2368       have "EX S. P S"
  2369       proof
  2370         show "P S" <...>
  2371       qed
  2372 
  2373   - Calculational reasoning with subst (or similar rules):
  2374     The proof pattern
  2375 
  2376       have "P (S::'a set)" <...>
  2377       also have "S = T" <...>
  2378       finally have "P T" .
  2379 
  2380     no longer works (for similar reasons as the previous example) and
  2381     must be replaced by something like
  2382 
  2383       have "P (S::'a set)" <...>
  2384       moreover have "S = T" <...>
  2385       ultimately have "P T" by simp
  2386 
  2387   - Tactics or packages written in ML code:
  2388     Code performing pattern matching on types via
  2389 
  2390       Type ("set", [T]) => ...
  2391 
  2392     must be rewritten. Moreover, functions like strip_type or
  2393     binder_types no longer return the right value when applied to a
  2394     type of the form
  2395 
  2396       T1 => ... => Tn => U => bool
  2397 
  2398     rather than
  2399 
  2400       T1 => ... => Tn => U set
  2401 
  2402 * Merged theories Wellfounded_Recursion, Accessible_Part and
  2403 Wellfounded_Relations to theory Wellfounded.
  2404 
  2405 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  2406 
  2407 * Class finite no longer treats UNIV as class parameter.  Use class
  2408 enum from theory Library/Enum instead to achieve a similar effect.
  2409 INCOMPATIBILITY.
  2410 
  2411 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  2412 and "Cons".  INCOMPATIBILITY.
  2413 
  2414 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  2415 Potential INCOMPATIBILITY.
  2416 
  2417 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  2418 injective_fst_snd removed, use split_eta and prod_eqI instead.
  2419 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  2420 
  2421 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  2422 the same name in theory Orderings:
  2423 
  2424   less_trans
  2425   less_linear
  2426   le_imp_less_or_eq
  2427   le_less_trans
  2428   less_le_trans
  2429   less_not_sym
  2430   less_asym
  2431 
  2432 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  2433 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  2434 and different variable names.
  2435 
  2436 * Library/Option_ord.thy: Canonical order on option type.
  2437 
  2438 * Library/RBT.thy: Red-black trees, an efficient implementation of
  2439 finite maps.
  2440 
  2441 * Library/Countable.thy: Type class for countable types.
  2442 
  2443 * Theory Int: The representation of numerals has changed.  The infix
  2444 operator BIT and the bit datatype with constructors B0 and B1 have
  2445 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  2446 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  2447 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  2448 accordingly.
  2449 
  2450 * Theory Nat: definition of <= and < on natural numbers no longer
  2451 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  2452 le_def and less_def have disappeared.  Consider lemmas not_less
  2453 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  2454 
  2455 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  2456 (whose purpose mainly is for various fold_set functionals) have been
  2457 abandoned in favor of the existing algebraic classes
  2458 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  2459 lower_semilattice (resp. upper_semilattice) and linorder.
  2460 INCOMPATIBILITY.
  2461 
  2462 * Theory Transitive_Closure: induct and cases rules now declare proper
  2463 case_names ("base" and "step").  INCOMPATIBILITY.
  2464 
  2465 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  2466 lattices.  The form set-specific version is available as
  2467 Inductive.lfp_ordinal_induct_set.
  2468 
  2469 * Renamed theorems "power.simps" to "power_int.simps".
  2470 INCOMPATIBILITY.
  2471 
  2472 * Class semiring_div provides basic abstract properties of semirings
  2473 with division and modulo operations.  Subsumes former class dvd_mod.
  2474 
  2475 * Merged theories IntDef, Numeral and IntArith into unified theory
  2476 Int.  INCOMPATIBILITY.
  2477 
  2478 * Theory Library/Code_Index: type "index" now represents natural
  2479 numbers rather than integers.  INCOMPATIBILITY.
  2480 
  2481 * New class "uminus" with operation "uminus" (split of from class
  2482 "minus" which now only has operation "minus", binary).
  2483 INCOMPATIBILITY.
  2484 
  2485 * Constants "card", "internal_split", "option_map" now with authentic
  2486 syntax.  INCOMPATIBILITY.
  2487 
  2488 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  2489 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  2490 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  2491 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  2492 Sup_set_def, le_def, less_def, option_map_def now with object
  2493 equality.  INCOMPATIBILITY.
  2494 
  2495 * Records. Removed K_record, and replaced it by pure lambda term
  2496 %x. c. The simplifier setup is now more robust against eta expansion.
  2497 INCOMPATIBILITY: in cases explicitly referring to K_record.
  2498 
  2499 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  2500 
  2501 * Library/ListVector: new theory of arithmetic vector operations.
  2502 
  2503 * Library/Order_Relation: new theory of various orderings as sets of
  2504 pairs.  Defines preorders, partial orders, linear orders and
  2505 well-orders on sets and on types.
  2506 
  2507 
  2508 *** ZF ***
  2509 
  2510 * Renamed some theories to allow to loading both ZF and HOL in the
  2511 same session:
  2512 
  2513   Datatype  -> Datatype_ZF
  2514   Inductive -> Inductive_ZF
  2515   Int       -> Int_ZF
  2516   IntDiv    -> IntDiv_ZF
  2517   Nat       -> Nat_ZF
  2518   List      -> List_ZF
  2519   Main      -> Main_ZF
  2520 
  2521 INCOMPATIBILITY: ZF theories that import individual theories below
  2522 Main might need to be adapted.  Regular theory Main is still
  2523 available, as trivial extension of Main_ZF.
  2524 
  2525 
  2526 *** ML ***
  2527 
  2528 * ML within Isar: antiquotation @{const name} or @{const
  2529 name(typargs)} produces statically-checked Const term.
  2530 
  2531 * Functor NamedThmsFun: data is available to the user as dynamic fact
  2532 (of the same name).  Removed obsolete print command.
  2533 
  2534 * Removed obsolete "use_legacy_bindings" function.
  2535 
  2536 * The ``print mode'' is now a thread-local value derived from a global
  2537 template (the former print_mode reference), thus access becomes
  2538 non-critical.  The global print_mode reference is for session
  2539 management only; user-code should use print_mode_value,
  2540 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  2541 
  2542 * Functions system/system_out provide a robust way to invoke external
  2543 shell commands, with propagation of interrupts (requires Poly/ML
  2544 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  2545 
  2546 
  2547 *** System ***
  2548 
  2549 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  2550 in accordance with Proof General 3.7, which prefers GNU emacs.
  2551 
  2552 * isatool tty runs Isabelle process with plain tty interaction;
  2553 optional line editor may be specified via ISABELLE_LINE_EDITOR
  2554 setting, the default settings attempt to locate "ledit" and "rlwrap".
  2555 
  2556 * isatool browser now works with Cygwin as well, using general
  2557 "javapath" function defined in Isabelle process environment.
  2558 
  2559 * YXML notation provides a simple and efficient alternative to
  2560 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  2561 isatool yxml as described in the Isabelle system manual.
  2562 
  2563 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  2564 provides general wrapper for managing an Isabelle process in a robust
  2565 fashion, with ``cooked'' output from stdin/stderr.
  2566 
  2567 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  2568 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  2569 
  2570 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  2571 way of changing the user's settings is via
  2572 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  2573 script.
  2574 
  2575 * Multithreading.max_threads := 0 refers to the number of actual CPU
  2576 cores of the underlying machine, which is a good starting point for
  2577 optimal performance tuning.  The corresponding usedir option -M allows
  2578 "max" as an alias for "0".  WARNING: does not work on certain versions
  2579 of Mac OS (with Poly/ML 5.1).
  2580 
  2581 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  2582 adverse effect of Isabelle flooding interactive front-ends (notably
  2583 ProofGeneral / XEmacs).
  2584 
  2585 
  2586 
  2587 New in Isabelle2007 (November 2007)
  2588 -----------------------------------
  2589 
  2590 *** General ***
  2591 
  2592 * More uniform information about legacy features, notably a
  2593 warning/error of "Legacy feature: ...", depending on the state of the
  2594 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  2595 legacy features will disappear eventually.
  2596 
  2597 * Theory syntax: the header format ``theory A = B + C:'' has been
  2598 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  2599 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  2600 
  2601 * Theory syntax: the old non-Isar theory file format has been
  2602 discontinued altogether.  Note that ML proof scripts may still be used
  2603 with Isar theories; migration is usually quite simple with the ML
  2604 function use_legacy_bindings.  INCOMPATIBILITY.
  2605 
  2606 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  2607 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  2608 quotes.
  2609 
  2610 * Theory loader: be more serious about observing the static theory
  2611 header specifications (including optional directories), but not the
  2612 accidental file locations of previously successful loads.  The strict
  2613 update policy of former update_thy is now already performed by
  2614 use_thy, so the former has been removed; use_thys updates several
  2615 theories simultaneously, just as 'imports' within a theory header
  2616 specification, but without merging the results.  Potential
  2617 INCOMPATIBILITY: may need to refine theory headers and commands
  2618 ROOT.ML which depend on load order.
  2619 
  2620 * Theory loader: optional support for content-based file
  2621 identification, instead of the traditional scheme of full physical
  2622 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  2623 (cf. the system manual).  The new scheme allows to work with
  2624 non-finished theories in persistent session images, such that source
  2625 files may be moved later on without requiring reloads.
  2626 
  2627 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2628 file (with the same base name as the theory) are considered a legacy
  2629 feature, which will disappear eventually. Even now, the theory loader
  2630 no longer maintains dependencies on such files.
  2631 
  2632 * Syntax: the scope for resolving ambiguities via type-inference is
  2633 now limited to individual terms, instead of whole simultaneous
  2634 specifications as before. This greatly reduces the complexity of the
  2635 syntax module and improves flexibility by separating parsing and
  2636 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  2637 'fixes' etc.) are required in rare situations.
  2638 
  2639 * Syntax: constants introduced by new-style packages ('definition',
  2640 'abbreviation' etc.) are passed through the syntax module in
  2641 ``authentic mode''. This means that associated mixfix annotations
  2642 really stick to such constants, independently of potential name space
  2643 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  2644 trees are represented slightly differently, may need to adapt syntax
  2645 translations accordingly. Use CONST marker in 'translations' and
  2646 @{const_syntax} antiquotation in 'parse_translation' etc.
  2647 
  2648 * Legacy goal package: reduced interface to the bare minimum required
  2649 to keep existing proof scripts running.  Most other user-level
  2650 functions are now part of the OldGoals structure, which is *not* open
  2651 by default (consider isatool expandshort before open OldGoals).
  2652 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  2653 these tend to cause confusion about the actual goal (!) context being
  2654 used here, which is not necessarily the same as the_context().
  2655 
  2656 * Command 'find_theorems': supports "*" wild-card in "name:"
  2657 criterion; "with_dups" option.  Certain ProofGeneral versions might
  2658 support a specific search form (see ProofGeneral/CHANGES).
  2659 
  2660 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  2661 by default, which means that "prems" (and also "fixed variables") are
  2662 suppressed from proof state output.  Note that the ProofGeneral
  2663 settings mechanism allows to change and save options persistently, but
  2664 older versions of Isabelle will fail to start up if a negative prems
  2665 limit is imposed.
  2666 
  2667 * Local theory targets may be specified by non-nested blocks of
  2668 ``context/locale/class ... begin'' followed by ``end''.  The body may
  2669 contain definitions, theorems etc., including any derived mechanism
  2670 that has been implemented on top of these primitives.  This concept
  2671 generalizes the existing ``theorem (in ...)'' towards more versatility
  2672 and scalability.
  2673 
  2674 * Proof General interface: proper undo of final 'end' command;
  2675 discontinued Isabelle/classic mode (ML proof scripts).
  2676 
  2677 
  2678 *** Document preparation ***
  2679 
  2680 * Added antiquotation @{theory name} which prints the given name,
  2681 after checking that it refers to a valid ancestor theory in the
  2682 current context.
  2683 
  2684 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  2685 check the given source text as ML type/structure, printing verbatim.
  2686 
  2687 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  2688 "c args == rhs" given in the current context.  (Any number of
  2689 arguments may be given on the LHS.)
  2690 
  2691 
  2692 *** Pure ***
  2693 
  2694 * The 'class' package offers a combination of axclass and locale to
  2695 achieve Haskell-like type classes in Isabelle.  Definitions and
  2696 theorems within a class context produce both relative results (with
  2697 implicit parameters according to the locale context), and polymorphic
  2698 constants with qualified polymorphism (according to the class
  2699 context).  Within the body context of a 'class' target, a separate
  2700 syntax layer ("user space type system") takes care of converting
  2701 between global polymorphic consts and internal locale representation.
  2702 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  2703 "isatool doc classes" provides a tutorial.
  2704 
  2705 * Generic code generator framework allows to generate executable
  2706 code for ML and Haskell (including Isabelle classes).  A short usage
  2707 sketch:
  2708 
  2709     internal compilation:
  2710         export_code <list of constants (term syntax)> in SML
  2711     writing SML code to a file:
  2712         export_code <list of constants (term syntax)> in SML <filename>
  2713     writing OCaml code to a file:
  2714         export_code <list of constants (term syntax)> in OCaml <filename>
  2715     writing Haskell code to a bunch of files:
  2716         export_code <list of constants (term syntax)> in Haskell <filename>
  2717 
  2718     evaluating closed propositions to True/False using code generation:
  2719         method ``eval''
  2720 
  2721 Reasonable default setup of framework in HOL.
  2722 
  2723 Theorem attributs for selecting and transforming function equations theorems:
  2724 
  2725     [code fun]:        select a theorem as function equation for a specific constant
  2726     [code fun del]:    deselect a theorem as function equation for a specific constant
  2727     [code inline]:     select an equation theorem for unfolding (inlining) in place
  2728     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  2729 
  2730 User-defined serializations (target in {SML, OCaml, Haskell}):
  2731 
  2732     code_const <and-list of constants (term syntax)>
  2733       {(target) <and-list of const target syntax>}+
  2734 
  2735     code_type <and-list of type constructors>
  2736       {(target) <and-list of type target syntax>}+
  2737 
  2738     code_instance <and-list of instances>
  2739       {(target)}+
  2740         where instance ::= <type constructor> :: <class>
  2741 
  2742     code_class <and_list of classes>
  2743       {(target) <and-list of class target syntax>}+
  2744         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  2745 
  2746 code_instance and code_class only are effective to target Haskell.
  2747 
  2748 For example usage see src/HOL/ex/Codegenerator.thy and
  2749 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  2750 generation from Isabelle/HOL theories is available via "isatool doc
  2751 codegen".
  2752 
  2753 * Code generator: consts in 'consts_code' Isar commands are now
  2754 referred to by usual term syntax (including optional type
  2755 annotations).
  2756 
  2757 * Command 'no_translations' removes translation rules from theory
  2758 syntax.
  2759 
  2760 * Overloaded definitions are now actually checked for acyclic
  2761 dependencies.  The overloading scheme is slightly more general than
  2762 that of Haskell98, although Isabelle does not demand an exact
  2763 correspondence to type class and instance declarations.
  2764 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  2765 exotic versions of overloading -- at the discretion of the user!
  2766 
  2767 Polymorphic constants are represented via type arguments, i.e. the
  2768 instantiation that matches an instance against the most general
  2769 declaration given in the signature.  For example, with the declaration
  2770 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  2771 as c(nat).  Overloading is essentially simultaneous structural
  2772 recursion over such type arguments.  Incomplete specification patterns
  2773 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  2774 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  2775 Command 'print_theory' outputs the normalized system of recursive
  2776 equations, see section "definitions".
  2777 
  2778 * Configuration options are maintained within the theory or proof
  2779 context (with name and type bool/int/string), providing a very simple
  2780 interface to a poor-man's version of general context data.  Tools may
  2781 declare options in ML (e.g. using Attrib.config_int) and then refer to
  2782 these values using Config.get etc.  Users may change options via an
  2783 associated attribute of the same name.  This form of context
  2784 declaration works particularly well with commands 'declare' or
  2785 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  2786 very easy to avoid global references, which would not observe Isar
  2787 toplevel undo/redo and fail to work with multithreading.
  2788 
  2789 Various global ML references of Pure and HOL have been turned into
  2790 configuration options:
  2791 
  2792   Unify.search_bound		unify_search_bound
  2793   Unify.trace_bound		unify_trace_bound
  2794   Unify.trace_simp		unify_trace_simp
  2795   Unify.trace_types		unify_trace_types
  2796   Simplifier.simp_depth_limit	simp_depth_limit
  2797   Blast.depth_limit		blast_depth_limit
  2798   DatatypeProp.dtK		datatype_distinctness_limit
  2799   fast_arith_neq_limit  	fast_arith_neq_limit
  2800   fast_arith_split_limit	fast_arith_split_limit
  2801 
  2802 * Named collections of theorems may be easily installed as context
  2803 data using the functor NamedThmsFun (see also
  2804 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  2805 attributes; there is also a toplevel print command.  This facility is
  2806 just a common case of general context data, which is the preferred way
  2807 for anything more complex than just a list of facts in canonical
  2808 order.
  2809 
  2810 * Isar: command 'declaration' augments a local theory by generic
  2811 declaration functions written in ML.  This enables arbitrary content
  2812 being added to the context, depending on a morphism that tells the
  2813 difference of the original declaration context wrt. the application
  2814 context encountered later on.
  2815 
  2816 * Isar: proper interfaces for simplification procedures.  Command
  2817 'simproc_setup' declares named simprocs (with match patterns, and body
  2818 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  2819 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  2820 
  2821 * Isar: an extra pair of brackets around attribute declarations
  2822 abbreviates a theorem reference involving an internal dummy fact,
  2823 which will be ignored later --- only the effect of the attribute on
  2824 the background context will persist.  This form of in-place
  2825 declarations is particularly useful with commands like 'declare' and
  2826 'using', for example ``have A using [[simproc a]] by simp''.
  2827 
  2828 * Isar: method "assumption" (and implicit closing of subproofs) now
  2829 takes simple non-atomic goal assumptions into account: after applying
  2830 an assumption as a rule the resulting subgoals are solved by atomic
  2831 assumption steps.  This is particularly useful to finish 'obtain'
  2832 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  2833 without referring to the original premise "!!x. P x ==> thesis" in the
  2834 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  2835 more permissive.
  2836 
  2837 * Isar: implicit use of prems from the Isar proof context is
  2838 considered a legacy feature.  Common applications like ``have A .''
  2839 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  2840 referencing facts explicitly here improves readability and
  2841 maintainability of proof texts.
  2842 
  2843 * Isar: improper proof element 'guess' is like 'obtain', but derives
  2844 the obtained context from the course of reasoning!  For example:
  2845 
  2846   assume "EX x y. A x & B y"   -- "any previous fact"
  2847   then guess x and y by clarify
  2848 
  2849 This technique is potentially adventurous, depending on the facts and
  2850 proof tools being involved here.
  2851 
  2852 * Isar: known facts from the proof context may be specified as literal
  2853 propositions, using ASCII back-quote syntax.  This works wherever
  2854 named facts used to be allowed so far, in proof commands, proof
  2855 methods, attributes etc.  Literal facts are retrieved from the context
  2856 according to unification of type and term parameters.  For example,
  2857 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  2858 theorems in the current context, then these are valid literal facts:
  2859 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  2860 
  2861 There is also a proof method "fact" which does the same composition
  2862 for explicit goal states, e.g. the following proof texts coincide with
  2863 certain special cases of literal facts:
  2864 
  2865   have "A" by fact                 ==  note `A`
  2866   have "A ==> B" by fact           ==  note `A ==> B`
  2867   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  2868   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  2869 
  2870 * Isar: ":" (colon) is no longer a symbolic identifier character in
  2871 outer syntax.  Thus symbolic identifiers may be used without
  2872 additional white space in declarations like this: ``assume *: A''.
  2873 
  2874 * Isar: 'print_facts' prints all local facts of the current context,
  2875 both named and unnamed ones.
  2876 
  2877 * Isar: 'def' now admits simultaneous definitions, e.g.:
  2878 
  2879   def x == "t" and y == "u"
  2880 
  2881 * Isar: added command 'unfolding', which is structurally similar to
  2882 'using', but affects both the goal state and facts by unfolding given
  2883 rewrite rules.  Thus many occurrences of the 'unfold' method or
  2884 'unfolded' attribute may be replaced by first-class proof text.
  2885 
  2886 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  2887 and command 'unfolding' now all support object-level equalities
  2888 (potentially conditional).  The underlying notion of rewrite rule is
  2889 analogous to the 'rule_format' attribute, but *not* that of the
  2890 Simplifier (which is usually more generous).
  2891 
  2892 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  2893 premises of a theorem by n. Useful in conjunction with drule.
  2894 
  2895 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  2896 method expression within a sandbox consisting of the first N
  2897 sub-goals, which need to exist.  For example, ``simp_all [3]''
  2898 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  2899 simplifies all new goals that emerge from applying rule foo to the
  2900 originally first one.
  2901 
  2902 * Isar: schematic goals are no longer restricted to higher-order
  2903 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  2904 expected.
  2905 
  2906 * Isar: the conclusion of a long theorem statement is now either
  2907 'shows' (a simultaneous conjunction, as before), or 'obtains'
  2908 (essentially a disjunction of cases with local parameters and
  2909 assumptions).  The latter allows to express general elimination rules
  2910 adequately; in this notation common elimination rules look like this:
  2911 
  2912   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  2913     assumes "EX x. P x"
  2914     obtains x where "P x"
  2915 
  2916   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  2917     assumes "A & B"
  2918     obtains A and B
  2919 
  2920   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  2921     assumes "A | B"
  2922     obtains
  2923       A
  2924     | B
  2925 
  2926 The subsequent classical rules even refer to the formal "thesis"
  2927 explicitly:
  2928 
  2929   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  2930     obtains "~ thesis"
  2931 
  2932   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  2933     obtains "thesis ==> something"
  2934 
  2935 The actual proof of an 'obtains' statement is analogous to that of the
  2936 Isar proof element 'obtain', only that there may be several cases.
  2937 Optional case names may be specified in parentheses; these will be
  2938 available both in the present proof and as annotations in the
  2939 resulting rule, for later use with the 'cases' method (cf. attribute
  2940 case_names).
  2941 
  2942 * Isar: the assumptions of a long theorem statement are available as
  2943 "assms" fact in the proof context.  This is more appropriate than the
  2944 (historical) "prems", which refers to all assumptions of the current
  2945 context, including those from the target locale, proof body etc.
  2946 
  2947 * Isar: 'print_statement' prints theorems from the current theory or
  2948 proof context in long statement form, according to the syntax of a
  2949 top-level lemma.
  2950 
  2951 * Isar: 'obtain' takes an optional case name for the local context
  2952 introduction rule (default "that").
  2953 
  2954 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  2955 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  2956 to occur.
  2957 
  2958 * Pure: syntax "CONST name" produces a fully internalized constant
  2959 according to the current context.  This is particularly useful for
  2960 syntax translations that should refer to internal constant
  2961 representations independently of name spaces.
  2962 
  2963 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  2964 instead of "FOO ". This allows multiple binder declarations to coexist
  2965 in the same context.  INCOMPATIBILITY.
  2966 
  2967 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  2968 primitive that also works in a locale context (both for constants and
  2969 fixed variables). Type declaration and internal syntactic representation
  2970 of given constants retrieved from the context. Likewise, the
  2971 'no_notation' command allows to remove given syntax annotations from the
  2972 current context.
  2973 
  2974 * Isar/locales: new derived specification elements 'axiomatization',
  2975 'definition', 'abbreviation', which support type-inference, admit
  2976 object-level specifications (equality, equivalence).  See also the
  2977 isar-ref manual.  Examples:
  2978 
  2979   axiomatization
  2980     eq  (infix "===" 50) where
  2981     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  2982 
  2983   definition "f x y = x + y + 1"
  2984   definition g where "g x = f x x"
  2985 
  2986   abbreviation
  2987     neq  (infix "=!=" 50) where
  2988     "x =!= y == ~ (x === y)"
  2989 
  2990 These specifications may be also used in a locale context.  Then the
  2991 constants being introduced depend on certain fixed parameters, and the
  2992 constant name is qualified by the locale base name.  An internal
  2993 abbreviation takes care for convenient input and output, making the
  2994 parameters implicit and using the original short name.  See also
  2995 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  2996 entities from a monomorphic theory.
  2997 
  2998 Presently, abbreviations are only available 'in' a target locale, but
  2999 not inherited by general import expressions.  Also note that
  3000 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3001 'translations' in common applications.  The "no_abbrevs" print mode
  3002 prevents folding of abbreviations in term output.
  3003 
  3004 Concrete syntax is attached to specified constants in internal form,
  3005 independently of name spaces.  The parse tree representation is
  3006 slightly different -- use 'notation' instead of raw 'syntax', and
  3007 'translations' with explicit "CONST" markup to accommodate this.
  3008 
  3009 * Pure/Isar: unified syntax for new-style specification mechanisms
  3010 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3011 full type inference and dummy patterns ("_").  For example:
  3012 
  3013   definition "K x _ = x"
  3014 
  3015   inductive conj for A B
  3016   where "A ==> B ==> conj A B"
  3017 
  3018 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3019 the current context.  Print mode "no_abbrevs" prevents inversion of
  3020 abbreviations on output.
  3021 
  3022 * Isar/locales: improved parameter handling: use of locales "var" and
  3023 "struct" no longer necessary; - parameter renamings are no longer
  3024 required to be injective.  For example, this allows to define
  3025 endomorphisms as locale endom = homom mult mult h.
  3026 
  3027 * Isar/locales: changed the way locales with predicates are defined.
  3028 Instead of accumulating the specification, the imported expression is
  3029 now an interpretation.  INCOMPATIBILITY: different normal form of
  3030 locale expressions.  In particular, in interpretations of locales with
  3031 predicates, goals repesenting already interpreted fragments are not
  3032 removed automatically.  Use methods `intro_locales' and
  3033 `unfold_locales'; see below.
  3034 
  3035 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3036 provide backward reasoning on locales predicates.  The methods are
  3037 aware of interpretations and discharge corresponding goals.
  3038 `intro_locales' is less aggressive then `unfold_locales' and does not
  3039 unfold predicates to assumptions.
  3040 
  3041 * Isar/locales: the order in which locale fragments are accumulated
  3042 has changed.  This enables to override declarations from fragments due
  3043 to interpretations -- for example, unwanted simp rules.
  3044 
  3045 * Isar/locales: interpretation in theories and proof contexts has been
  3046 extended.  One may now specify (and prove) equations, which are
  3047 unfolded in interpreted theorems.  This is useful for replacing
  3048 defined concepts (constants depending on locale parameters) by
  3049 concepts already existing in the target context.  Example:
  3050 
  3051   interpretation partial_order ["op <= :: [int, int] => bool"]
  3052     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3053 
  3054 Typically, the constant `partial_order.less' is created by a
  3055 definition specification element in the context of locale
  3056 partial_order.
  3057 
  3058 * Method "induct": improved internal context management to support
  3059 local fixes and defines on-the-fly. Thus explicit meta-level
  3060 connectives !!  and ==> are rarely required anymore in inductive goals
  3061 (using object-logic connectives for this purpose has been long
  3062 obsolete anyway). Common proof patterns are explained in
  3063 src/HOL/Induct/Common_Patterns.thy, see also
  3064 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3065 examples.
  3066 
  3067 * Method "induct": improved handling of simultaneous goals. Instead of
  3068 introducing object-level conjunction, the statement is now split into
  3069 several conclusions, while the corresponding symbolic cases are nested
  3070 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3071 see src/HOL/Induct/Common_Patterns.thy, for example.
  3072 
  3073 * Method "induct": mutual induction rules are now specified as a list
  3074 of rule sharing the same induction cases. HOL packages usually provide
  3075 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3076 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3077 mutual induction rules differently, i.e. like this:
  3078 
  3079   (induct rule: foo_bar.inducts)
  3080   (induct set: foo bar)
  3081   (induct pred: foo bar)
  3082   (induct type: foo bar)
  3083 
  3084 The ML function ProjectRule.projections turns old-style rules into the
  3085 new format.
  3086 
  3087 * Method "coinduct": dual of induction, see
  3088 src/HOL/Library/Coinductive_List.thy for various examples.
  3089 
  3090 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3091 considered a legacy feature.
  3092 
  3093 * Attribute "symmetric" produces result with standardized schematic
  3094 variables (index 0).  Potential INCOMPATIBILITY.
  3095 
  3096 * Simplifier: by default the simplifier trace only shows top level
  3097 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3098 default. Thus there is less danger of being flooded by the trace. The
  3099 trace indicates where parts have been suppressed.
  3100   
  3101 * Provers/classical: removed obsolete classical version of elim_format
  3102 attribute; classical elim/dest rules are now treated uniformly when
  3103 manipulating the claset.
  3104 
  3105 * Provers/classical: stricter checks to ensure that supplied intro,
  3106 dest and elim rules are well-formed; dest and elim rules must have at
  3107 least one premise.
  3108 
  3109 * Provers/classical: attributes dest/elim/intro take an optional
  3110 weight argument for the rule (just as the Pure versions).  Weights are
  3111 ignored by automated tools, but determine the search order of single
  3112 rule steps.
  3113 
  3114 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3115 where the body does not mention the bound variable.  Note that dummy
  3116 patterns implicitly depend on their context of bounds, which makes
  3117 "{_. _}" match any set comprehension as expected.  Potential
  3118 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3119 constant "_idtdummy" in the binding position.
  3120 
  3121 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3122 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3123 for example "A -> B" => "Pi A (%_. B)".
  3124 
  3125 * Pure: 'class_deps' command visualizes the subclass relation, using
  3126 the graph browser tool.
  3127 
  3128 * Pure: 'print_theory' now suppresses certain internal declarations by
  3129 default; use '!' option for full details.
  3130 
  3131 
  3132 *** HOL ***
  3133 
  3134 * Method "metis" proves goals by applying the Metis general-purpose
  3135 resolution prover (see also http://gilith.com/software/metis/).
  3136 Examples are in the directory MetisExamples.  WARNING: the
  3137 Isabelle/HOL-Metis integration does not yet work properly with
  3138 multi-threading.
  3139   
  3140 * Command 'sledgehammer' invokes external automatic theorem provers as
  3141 background processes.  It generates calls to the "metis" method if
  3142 successful. These can be pasted into the proof.  Users do not have to
  3143 wait for the automatic provers to return.  WARNING: does not really
  3144 work with multi-threading.
  3145 
  3146 * New "auto_quickcheck" feature tests outermost goal statements for
  3147 potential counter-examples.  Controlled by ML references
  3148 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3149 5000 milliseconds).  Fails silently if statements is outside of
  3150 executable fragment, or any other codgenerator problem occurs.
  3151 
  3152 * New constant "undefined" with axiom "undefined x = undefined".
  3153 
  3154 * Added class "HOL.eq", allowing for code generation with polymorphic
  3155 equality.
  3156 
  3157 * Some renaming of class constants due to canonical name prefixing in
  3158 the new 'class' package:
  3159 
  3160     HOL.abs ~> HOL.abs_class.abs
  3161     HOL.divide ~> HOL.divide_class.divide
  3162     0 ~> HOL.zero_class.zero
  3163     1 ~> HOL.one_class.one
  3164     op + ~> HOL.plus_class.plus
  3165     op - ~> HOL.minus_class.minus
  3166     uminus ~> HOL.minus_class.uminus
  3167     op * ~> HOL.times_class.times
  3168     op < ~> HOL.ord_class.less
  3169     op <= > HOL.ord_class.less_eq
  3170     Nat.power ~> Power.power_class.power
  3171     Nat.size ~> Nat.size_class.size
  3172     Numeral.number_of ~> Numeral.number_class.number_of
  3173     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3174     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3175     Orderings.min ~> Orderings.ord_class.min
  3176     Orderings.max ~> Orderings.ord_class.max
  3177     Divides.op div ~> Divides.div_class.div
  3178     Divides.op mod ~> Divides.div_class.mod
  3179     Divides.op dvd ~> Divides.div_class.dvd
  3180 
  3181 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3182 
  3183 a) User-defined constants using any of the names "plus", "minus",
  3184 "times", "less" or "less_eq". The standard syntax translations for
  3185 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3186 names.
  3187 
  3188 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3189 INCOMPATIBILITY: use more specific names.
  3190 
  3191 c) Permutative equations (e.g. "a + b = b + a")
  3192 Since the change of names also changes the order of terms, permutative
  3193 rewrite rules may get applied in a different order. Experience shows
  3194 that this is rarely the case (only two adaptions in the whole Isabelle
  3195 distribution).  INCOMPATIBILITY: rewrite proofs
  3196 
  3197 d) ML code directly refering to constant names
  3198 This in general only affects hand-written proof tactics, simprocs and
  3199 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3200 Consider using @{const_name} antiquotation.
  3201 
  3202 * New class "default" with associated constant "default".
  3203 
  3204 * Function "sgn" is now overloaded and available on int, real, complex
  3205 (and other numeric types), using class "sgn".  Two possible defs of
  3206 sgn are given as equational assumptions in the classes sgn_if and
  3207 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3208 INCOMPATIBILITY.
  3209 
  3210 * Locale "partial_order" now unified with class "order" (cf. theory
  3211 Orderings), added parameter "less".  INCOMPATIBILITY.
  3212 
  3213 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3214 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3215 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3216 
  3217 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3218 changed order of proof goals in instance proofs.
  3219 
  3220 * The transitivity reasoner for partial and linear orders is set up
  3221 for classes "order" and "linorder".  Instances of the reasoner are available
  3222 in all contexts importing or interpreting the corresponding locales.
  3223 Method "order" invokes the reasoner separately; the reasoner
  3224 is also integrated with the Simplifier as a solver.  Diagnostic
  3225 command 'print_orders' shows the available instances of the reasoner
  3226 in the current context.
  3227 
  3228 * Localized monotonicity predicate in theory "Orderings"; integrated
  3229 lemmas max_of_mono and min_of_mono with this predicate.
  3230 INCOMPATIBILITY.
  3231 
  3232 * Formulation of theorem "dense" changed slightly due to integration
  3233 with new class dense_linear_order.
  3234 
  3235 * Uniform lattice theory development in HOL.
  3236 
  3237     constants "meet" and "join" now named "inf" and "sup"
  3238     constant "Meet" now named "Inf"
  3239 
  3240     classes "meet_semilorder" and "join_semilorder" now named
  3241       "lower_semilattice" and "upper_semilattice"
  3242     class "lorder" now named "lattice"
  3243     class "comp_lat" now named "complete_lattice"
  3244 
  3245     Instantiation of lattice classes allows explicit definitions
  3246     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3247 
  3248   INCOMPATIBILITY.  Theorem renames:
  3249 
  3250     meet_left_le            ~> inf_le1
  3251     meet_right_le           ~> inf_le2
  3252     join_left_le            ~> sup_ge1
  3253     join_right_le           ~> sup_ge2
  3254     meet_join_le            ~> inf_sup_ord
  3255     le_meetI                ~> le_infI
  3256     join_leI                ~> le_supI
  3257     le_meet                 ~> le_inf_iff
  3258     le_join                 ~> ge_sup_conv
  3259     meet_idempotent         ~> inf_idem
  3260     join_idempotent         ~> sup_idem
  3261     meet_comm               ~> inf_commute
  3262     join_comm               ~> sup_commute
  3263     meet_leI1               ~> le_infI1
  3264     meet_leI2               ~> le_infI2
  3265     le_joinI1               ~> le_supI1
  3266     le_joinI2               ~> le_supI2
  3267     meet_assoc              ~> inf_assoc
  3268     join_assoc              ~> sup_assoc
  3269     meet_left_comm          ~> inf_left_commute
  3270     meet_left_idempotent    ~> inf_left_idem
  3271     join_left_comm          ~> sup_left_commute
  3272     join_left_idempotent    ~> sup_left_idem
  3273     meet_aci                ~> inf_aci
  3274     join_aci                ~> sup_aci
  3275     le_def_meet             ~> le_iff_inf
  3276     le_def_join             ~> le_iff_sup
  3277     join_absorp2            ~> sup_absorb2
  3278     join_absorp1            ~> sup_absorb1
  3279     meet_absorp1            ~> inf_absorb1
  3280     meet_absorp2            ~> inf_absorb2
  3281     meet_join_absorp        ~> inf_sup_absorb
  3282     join_meet_absorp        ~> sup_inf_absorb
  3283     distrib_join_le         ~> distrib_sup_le
  3284     distrib_meet_le         ~> distrib_inf_le
  3285 
  3286     add_meet_distrib_left   ~> add_inf_distrib_left
  3287     add_join_distrib_left   ~> add_sup_distrib_left
  3288     is_join_neg_meet        ~> is_join_neg_inf
  3289     is_meet_neg_join        ~> is_meet_neg_sup
  3290     add_meet_distrib_right  ~> add_inf_distrib_right
  3291     add_join_distrib_right  ~> add_sup_distrib_right
  3292     add_meet_join_distribs  ~> add_sup_inf_distribs
  3293     join_eq_neg_meet        ~> sup_eq_neg_inf
  3294     meet_eq_neg_join        ~> inf_eq_neg_sup
  3295     add_eq_meet_join        ~> add_eq_inf_sup
  3296     meet_0_imp_0            ~> inf_0_imp_0
  3297     join_0_imp_0            ~> sup_0_imp_0
  3298     meet_0_eq_0             ~> inf_0_eq_0
  3299     join_0_eq_0             ~> sup_0_eq_0
  3300     neg_meet_eq_join        ~> neg_inf_eq_sup
  3301     neg_join_eq_meet        ~> neg_sup_eq_inf
  3302     join_eq_if              ~> sup_eq_if
  3303 
  3304     mono_meet               ~> mono_inf
  3305     mono_join               ~> mono_sup
  3306     meet_bool_eq            ~> inf_bool_eq
  3307     join_bool_eq            ~> sup_bool_eq
  3308     meet_fun_eq             ~> inf_fun_eq
  3309     join_fun_eq             ~> sup_fun_eq
  3310     meet_set_eq             ~> inf_set_eq
  3311     join_set_eq             ~> sup_set_eq
  3312     meet1_iff               ~> inf1_iff
  3313     meet2_iff               ~> inf2_iff
  3314     meet1I                  ~> inf1I
  3315     meet2I                  ~> inf2I
  3316     meet1D1                 ~> inf1D1
  3317     meet2D1                 ~> inf2D1
  3318     meet1D2                 ~> inf1D2
  3319     meet2D2                 ~> inf2D2
  3320     meet1E                  ~> inf1E
  3321     meet2E                  ~> inf2E
  3322     join1_iff               ~> sup1_iff
  3323     join2_iff               ~> sup2_iff
  3324     join1I1                 ~> sup1I1
  3325     join2I1                 ~> sup2I1
  3326     join1I1                 ~> sup1I1
  3327     join2I2                 ~> sup1I2
  3328     join1CI                 ~> sup1CI
  3329     join2CI                 ~> sup2CI
  3330     join1E                  ~> sup1E
  3331     join2E                  ~> sup2E
  3332 
  3333     is_meet_Meet            ~> is_meet_Inf
  3334     Meet_bool_def           ~> Inf_bool_def
  3335     Meet_fun_def            ~> Inf_fun_def
  3336     Meet_greatest           ~> Inf_greatest
  3337     Meet_lower              ~> Inf_lower
  3338     Meet_set_def            ~> Inf_set_def
  3339 
  3340     Sup_def                 ~> Sup_Inf
  3341     Sup_bool_eq             ~> Sup_bool_def
  3342     Sup_fun_eq              ~> Sup_fun_def
  3343     Sup_set_eq              ~> Sup_set_def
  3344 
  3345     listsp_meetI            ~> listsp_infI
  3346     listsp_meet_eq          ~> listsp_inf_eq
  3347 
  3348     meet_min                ~> inf_min
  3349     join_max                ~> sup_max
  3350 
  3351 * Added syntactic class "size"; overloaded constant "size" now has
  3352 type "'a::size ==> bool"
  3353 
  3354 * Internal reorganisation of `size' of datatypes: size theorems
  3355 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3356 simplification rules by default!); theorems "prod.size" now named
  3357 "*.size".
  3358 
  3359 * Class "div" now inherits from class "times" rather than "type".
  3360 INCOMPATIBILITY.
  3361 
  3362 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  3363 Linorder etc.  have disappeared; operations defined in terms of
  3364 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  3365 
  3366 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  3367 
  3368 * HOL-Word: New extensive library and type for generic, fixed size
  3369 machine words, with arithemtic, bit-wise, shifting and rotating
  3370 operations, reflection into int, nat, and bool lists, automation for
  3371 linear arithmetic (by automatic reflection into nat or int), including
  3372 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  3373 arithmetic type classes, supporting automatic simplification of
  3374 numerals on all operations.
  3375 
  3376 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  3377 
  3378 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  3379 
  3380 * Code generator library theories:
  3381   - Code_Integer represents HOL integers by big integer literals in target
  3382     languages.
  3383   - Code_Char represents HOL characters by character literals in target
  3384     languages.
  3385   - Code_Char_chr like Code_Char, but also offers treatment of character
  3386     codes; includes Code_Integer.
  3387   - Executable_Set allows to generate code for finite sets using lists.
  3388   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  3389     denominator).
  3390   - Executable_Real implements a subset of real numbers, namly those
  3391     representable by rational numbers.
  3392   - Efficient_Nat implements natural numbers by integers, which in general will
  3393     result in higher efficency; pattern matching with 0/Suc is eliminated;
  3394     includes Code_Integer.
  3395   - Code_Index provides an additional datatype index which is mapped to
  3396     target-language built-in integers.
  3397   - Code_Message provides an additional datatype message_string which is isomorphic to
  3398     strings; messages are mapped to target-language strings.
  3399 
  3400 * New package for inductive predicates
  3401 
  3402   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  3403 
  3404     inductive
  3405       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3406       for z_1 :: U_1 and ... and z_n :: U_m
  3407     where
  3408       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3409     | ...
  3410 
  3411   with full support for type-inference, rather than
  3412 
  3413     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3414 
  3415     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3416     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3417 
  3418     inductive "s z_1 ... z_m"
  3419     intros
  3420       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3421       ...
  3422 
  3423   For backward compatibility, there is a wrapper allowing inductive
  3424   sets to be defined with the new package via
  3425 
  3426     inductive_set
  3427       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3428       for z_1 :: U_1 and ... and z_n :: U_m
  3429     where
  3430       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3431     | ...
  3432 
  3433   or
  3434 
  3435     inductive_set
  3436       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3437       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3438       for z_1 :: U_1 and ... and z_n :: U_m
  3439     where
  3440       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3441     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3442     | ...
  3443 
  3444   if the additional syntax "p ..." is required.
  3445 
  3446   Numerous examples can be found in the subdirectories src/HOL/Auth,
  3447   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  3448 
  3449   INCOMPATIBILITIES:
  3450 
  3451   - Since declaration and definition of inductive sets or predicates
  3452     is no longer separated, abbreviations involving the newly
  3453     introduced sets or predicates must be specified together with the
  3454     introduction rules after the 'where' keyword (see above), rather
  3455     than before the actual inductive definition.
  3456 
  3457   - The variables in induction and elimination rules are now
  3458     quantified in the order of their occurrence in the introduction
  3459     rules, rather than in alphabetical order. Since this may break
  3460     some proofs, these proofs either have to be repaired, e.g. by
  3461     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  3462     statements of the form
  3463 
  3464       case (rule_i a_i_1 ... a_i_{k_i})
  3465 
  3466     or the old order of quantification has to be restored by explicitly adding
  3467     meta-level quantifiers in the introduction rules, i.e.
  3468 
  3469       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  3470 
  3471   - The format of the elimination rules is now
  3472 
  3473       p z_1 ... z_m x_1 ... x_n ==>
  3474         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3475         ==> ... ==> P
  3476 
  3477     for predicates and
  3478 
  3479       (x_1, ..., x_n) : s z_1 ... z_m ==>
  3480         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3481         ==> ... ==> P
  3482 
  3483     for sets rather than
  3484 
  3485       x : s z_1 ... z_m ==>
  3486         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  3487         ==> ... ==> P
  3488 
  3489     This may require terms in goals to be expanded to n-tuples
  3490     (e.g. using case_tac or simplification with the split_paired_all
  3491     rule) before the above elimination rule is applicable.
  3492 
  3493   - The elimination or case analysis rules for (mutually) inductive
  3494     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  3495     list of rules "p_1_..._p_k.elims" is no longer available.
  3496 
  3497 * New package "function"/"fun" for general recursive functions,
  3498 supporting mutual and nested recursion, definitions in local contexts,
  3499 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  3500 for small examples, and the separate tutorial on the function
  3501 package. The old recdef "package" is still available as before, but
  3502 users are encouraged to use the new package.
  3503 
  3504 * Method "lexicographic_order" automatically synthesizes termination
  3505 relations as lexicographic combinations of size measures. 
  3506 
  3507 * Case-expressions allow arbitrary constructor-patterns (including
  3508 "_") and take their order into account, like in functional
  3509 programming.  Internally, this is translated into nested
  3510 case-expressions; missing cases are added and mapped to the predefined
  3511 constant "undefined". In complicated cases printing may no longer show
  3512 the original input but the internal form. Lambda-abstractions allow
  3513 the same form of pattern matching: "% pat1 => e1 | ..." is an
  3514 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  3515 variable.
  3516 
  3517 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  3518 is an abbreviation for "of_nat :: nat => int". The simplification
  3519 rules for "of_nat" have been changed to work like "int" did
  3520 previously.  Potential INCOMPATIBILITY:
  3521   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  3522   - of_nat_diff and of_nat_mult are no longer default simp rules
  3523 
  3524 * Method "algebra" solves polynomial equations over (semi)rings using
  3525 Groebner bases. The (semi)ring structure is defined by locales and the
  3526 tool setup depends on that generic context. Installing the method for
  3527 a specific type involves instantiating the locale and possibly adding
  3528 declarations for computation on the coefficients.  The method is
  3529 already instantiated for natural numbers and for the axiomatic class
  3530 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  3531 CALCULEMUS 2007 for the general principles underlying this
  3532 architecture of context-aware proof-tools.
  3533 
  3534 * Method "ferrack" implements quantifier elimination over
  3535 special-purpose dense linear orders using locales (analogous to
  3536 "algebra"). The method is already installed for class
  3537 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  3538 rat, etc.
  3539 
  3540 * Former constant "List.op @" now named "List.append".  Use ML
  3541 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  3542 circumvent possible incompatibilities when working on ML level.
  3543 
  3544 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  3545 
  3546 * New function listsum :: 'a list => 'a for arbitrary monoids.
  3547 Special syntax: "SUM x <- xs. f x" (and latex variants)
  3548 
  3549 * New syntax for Haskell-like list comprehension (input only), eg.
  3550 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  3551 
  3552 * The special syntax for function "filter" has changed from [x :
  3553 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  3554 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  3555 
  3556 * [a..b] is now defined for arbitrary linear orders.  It used to be
  3557 defined on nat only, as an abbreviation for [a..<Suc b]
  3558 INCOMPATIBILITY.
  3559 
  3560 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  3561 
  3562 * New functions "sorted" and "sort" in src/HOL/List.thy.
  3563 
  3564 * New lemma collection field_simps (an extension of ring_simps) for
  3565 manipulating (in)equations involving division. Multiplies with all
  3566 denominators that can be proved to be non-zero (in equations) or
  3567 positive/negative (in inequations).
  3568 
  3569 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  3570 have been improved and renamed to ring_simps, group_simps and
  3571 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  3572 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  3573 
  3574 * Theory Library/Commutative_Ring: switched from recdef to function
  3575 package; constants add, mul, pow now curried.  Infix syntax for
  3576 algebraic operations.
  3577 
  3578 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  3579 INCOMPATIBILITY.
  3580 
  3581 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  3582 INCOMPATIBILITY.
  3583 
  3584 * HOL/records: generalised field-update to take a function on the
  3585 field rather than the new value: r(|A := x|) is translated to A_update
  3586 (K x) r The K-combinator that is internally used is called K_record.
  3587 INCOMPATIBILITY: Usage of the plain update functions has to be
  3588 adapted.
  3589  
  3590 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  3591 * x = 0, which are required for a semiring.  Richer structures do not
  3592 inherit from semiring_0 anymore, because this property is a theorem
  3593 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  3594 there is more to prove, but this is mostly trivial.
  3595 
  3596 * Class "recpower" is generalized to arbitrary monoids, not just
  3597 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  3598 commutativity or semiring properties additionally.
  3599 
  3600 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  3601 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  3602 better use 'abbreviation'.
  3603 
  3604 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  3605 
  3606 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  3607 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  3608 significant changes for setting up numeral syntax for types:
  3609   - New constants Numeral.pred and Numeral.succ instead
  3610       of former Numeral.bin_pred and Numeral.bin_succ.
  3611   - Use integer operations instead of bin_add, bin_mult and so on.
  3612   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  3613   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  3614 
  3615 See src/HOL/Integ/IntArith.thy for an example setup.
  3616 
  3617 * Command 'normal_form' computes the normal form of a term that may
  3618 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  3619 produces ``[b, c, a]'' (without proof).  This command is suitable for
  3620 heavy-duty computations because the functions are compiled to ML
  3621 first.  Correspondingly, a method "normalization" is provided.  See
  3622 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  3623 
  3624 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  3625 25 like -->); output depends on the "iff" print_mode, the default is
  3626 "A = B" (with priority 50).
  3627 
  3628 * Relations less (<) and less_eq (<=) are also available on type bool.
  3629 Modified syntax to disallow nesting without explicit parentheses,
  3630 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  3631 INCOMPATIBILITY.
  3632 
  3633 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  3634 
  3635 * Relation composition operator "op O" now has precedence 75 and binds
  3636 stronger than union and intersection. INCOMPATIBILITY.
  3637 
  3638 * The old set interval syntax "{m..n(}" (and relatives) has been
  3639 removed.  Use "{m..<n}" (and relatives) instead.
  3640 
  3641 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  3642 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  3643 ``declare [[simproc del: neq]]''.
  3644 
  3645 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  3646 True/False.
  3647 
  3648 * Theorem Cons_eq_map_conv no longer declared as "simp".
  3649 
  3650 * Theorem setsum_mult renamed to setsum_right_distrib.
  3651 
  3652 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  3653 ``rule'' method.
  3654 
  3655 * Reimplemented methods "sat" and "satx", with several improvements:
  3656 goals no longer need to be stated as "<prems> ==> False", equivalences
  3657 (i.e. "=" on type bool) are handled, variable names of the form
  3658 "lit_<n>" are no longer reserved, significant speedup.
  3659 
  3660 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  3661 zChaff is still supported as well.
  3662 
  3663 * 'inductive' and 'datatype': provide projections of mutual rules,
  3664 bundled as foo_bar.inducts;
  3665 
  3666 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  3667 Library.
  3668 
  3669 * Library: moved theory Accessible_Part to main HOL.
  3670 
  3671 * Library: added theory Coinductive_List of potentially infinite lists
  3672 as greatest fixed-point.
  3673 
  3674 * Library: added theory AssocList which implements (finite) maps as
  3675 association lists.
  3676 
  3677 * Method "evaluation" solves goals (i.e. a boolean expression)
  3678 efficiently by compiling it to ML.  The goal is "proved" (via an
  3679 oracle) if it evaluates to True.
  3680 
  3681 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  3682 also when invoked by the simplifier.  This results in the Simplifier
  3683 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  3684 Configuration option fast_arith_split_limit=0 recovers the old
  3685 behavior.
  3686 
  3687 * Support for hex (0x20) and binary (0b1001) numerals.
  3688 
  3689 * New method: reify eqs (t), where eqs are equations for an
  3690 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  3691 parameter, computes a term s::'b and a list xs::'a list and proves the
  3692 theorem I xs s = t. This is also known as reification or quoting. The
  3693 resulting theorem is applied to the subgoal to substitute t with I xs
  3694 s.  If t is omitted, the subgoal itself is reified.
  3695 
  3696 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  3697 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  3698 where f is supposed to be a computable function (in the sense of code
  3699 generattion). The method uses reify to compute s and xs as above then
  3700 applies corr_thm and uses normalization by evaluation to "prove" f s =
  3701 r and finally gets the theorem t = r, which is again applied to the
  3702 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  3703 
  3704 * Reflection: Automatic reification now handels binding, an example is
  3705 available in src/HOL/ex/ReflectionEx.thy
  3706 
  3707 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  3708 command 'statespace' that is similar to 'record', but introduces an
  3709 abstract specification based on the locale infrastructure instead of
  3710 HOL types.  This leads to extra flexibility in composing state spaces,
  3711 in particular multiple inheritance and renaming of components.
  3712 
  3713 
  3714 *** HOL-Complex ***
  3715 
  3716 * Hyperreal: Functions root and sqrt are now defined on negative real
  3717 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  3718 Nonnegativity side conditions have been removed from many lemmas, so
  3719 that more subgoals may now be solved by simplification; potential
  3720 INCOMPATIBILITY.
  3721 
  3722 * Real: new type classes formalize real normed vector spaces and
  3723 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  3724 and norm :: 'a => real.
  3725 
  3726 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  3727 reals into other types. The overloaded constant Reals :: 'a set is now
  3728 defined as range of_real; potential INCOMPATIBILITY.
  3729 
  3730 * Real: proper support for ML code generation, including 'quickcheck'.
  3731 Reals are implemented as arbitrary precision rationals.
  3732 
  3733 * Hyperreal: Several constants that previously worked only for the
  3734 reals have been generalized, so they now work over arbitrary vector
  3735 spaces. Type annotations may need to be added in some cases; potential
  3736 INCOMPATIBILITY.
  3737 
  3738   Infinitesimal  :: ('a::real_normed_vector) star set
  3739   HFinite        :: ('a::real_normed_vector) star set
  3740   HInfinite      :: ('a::real_normed_vector) star set
  3741   approx         :: ('a::real_normed_vector) star => 'a star => bool
  3742   monad          :: ('a::real_normed_vector) star => 'a star set
  3743   galaxy         :: ('a::real_normed_vector) star => 'a star set
  3744   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  3745   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  3746   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  3747   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  3748   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  3749   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  3750   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  3751   sgn            :: 'a::real_normed_vector => 'a
  3752   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  3753 
  3754 * Complex: Some complex-specific constants are now abbreviations for
  3755 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  3756 hnorm.  Other constants have been entirely removed in favor of the
  3757 polymorphic versions (INCOMPATIBILITY):
  3758 
  3759   approx        <-- capprox
  3760   HFinite       <-- CFinite
  3761   HInfinite     <-- CInfinite
  3762   Infinitesimal <-- CInfinitesimal
  3763   monad         <-- cmonad
  3764   galaxy        <-- cgalaxy
  3765   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  3766   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  3767   (ns)deriv     <-- (ns)cderiv
  3768 
  3769 
  3770 *** HOL-Algebra ***
  3771 
  3772 * Formalisation of ideals and the quotient construction over rings.
  3773 
  3774 * Order and lattice theory no longer based on records.
  3775 INCOMPATIBILITY.
  3776 
  3777 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  3778 greatest_closed.  INCOMPATIBILITY.
  3779 
  3780 * Method algebra is now set up via an attribute.  For examples see
  3781 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  3782 of algebraic structures.
  3783 
  3784 * Renamed theory CRing to Ring.
  3785 
  3786 
  3787 *** HOL-Nominal ***
  3788 
  3789 * Substantial, yet incomplete support for nominal datatypes (binding
  3790 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  3791 src/HOL/Nominal/Examples.  Prospective users should consult
  3792 http://isabelle.in.tum.de/nominal/
  3793 
  3794 
  3795 *** ML ***
  3796 
  3797 * ML basics: just one true type int, which coincides with IntInf.int
  3798 (even on SML/NJ).
  3799 
  3800 * ML within Isar: antiquotations allow to embed statically-checked
  3801 formal entities in the source, referring to the context available at
  3802 compile-time.  For example:
  3803 
  3804 ML {* @{sort "{zero,one}"} *}
  3805 ML {* @{typ "'a => 'b"} *}
  3806 ML {* @{term "%x. x"} *}
  3807 ML {* @{prop "x == y"} *}
  3808 ML {* @{ctyp "'a => 'b"} *}
  3809 ML {* @{cterm "%x. x"} *}
  3810 ML {* @{cprop "x == y"} *}
  3811 ML {* @{thm asm_rl} *}
  3812 ML {* @{thms asm_rl} *}
  3813 ML {* @{type_name c} *}
  3814 ML {* @{type_syntax c} *}
  3815 ML {* @{const_name c} *}
  3816 ML {* @{const_syntax c} *}
  3817 ML {* @{context} *}
  3818 ML {* @{theory} *}
  3819 ML {* @{theory Pure} *}
  3820 ML {* @{theory_ref} *}
  3821 ML {* @{theory_ref Pure} *}
  3822 ML {* @{simpset} *}
  3823 ML {* @{claset} *}
  3824 ML {* @{clasimpset} *}
  3825 
  3826 The same works for sources being ``used'' within an Isar context.
  3827 
  3828 * ML in Isar: improved error reporting; extra verbosity with
  3829 ML_Context.trace enabled.
  3830 
  3831 * Pure/General/table.ML: the join operations now works via exceptions
  3832 DUP/SAME instead of type option. This is simpler in simple cases, and
  3833 admits slightly more efficient complex applications.
  3834 
  3835 * Pure: 'advanced' translation functions (parse_translation etc.) now
  3836 use Context.generic instead of just theory.
  3837 
  3838 * Pure: datatype Context.generic joins theory/Proof.context and
  3839 provides some facilities for code that works in either kind of
  3840 context, notably GenericDataFun for uniform theory and proof data.
  3841 
  3842 * Pure: simplified internal attribute type, which is now always
  3843 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  3844 local (Proof.context) attributes have been discontinued, while
  3845 minimizing code duplication. Thm.rule_attribute and
  3846 Thm.declaration_attribute build canonical attributes; see also structure
  3847 Context for further operations on Context.generic, notably
  3848 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  3849 declarations and definitions.
  3850 
  3851 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  3852 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  3853 init only required for impure data. INCOMPATIBILITY: empty really need
  3854 to be empty (no dependencies on theory content!)
  3855 
  3856 * Pure/kernel: consts certification ignores sort constraints given in
  3857 signature declarations. (This information is not relevant to the
  3858 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  3859 potential INCOMPATIBILITY.
  3860 
  3861 * Pure: axiomatic type classes are now purely definitional, with
  3862 explicit proofs of class axioms and super class relations performed
  3863 internally. See Pure/axclass.ML for the main internal interfaces --
  3864 notably AxClass.define_class supercedes AxClass.add_axclass, and
  3865 AxClass.axiomatize_class/classrel/arity supersede
  3866 Sign.add_classes/classrel/arities.
  3867 
  3868 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  3869 global/local versions on theory vs. Proof.context have been
  3870 discontinued; Attrib.syntax and Method.syntax have been adapted
  3871 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  3872 attributes, methods, etc.
  3873 
  3874 * Pure: several functions of signature "... -> theory -> theory * ..."
  3875 have been reoriented to "... -> theory -> ... * theory" in order to
  3876 allow natural usage in combination with the ||>, ||>>, |-> and
  3877 fold_map combinators.
  3878 
  3879 * Pure: official theorem names (closed derivations) and additional
  3880 comments (tags) are now strictly separate.  Name hints -- which are
  3881 maintained as tags -- may be attached any time without affecting the
  3882 derivation.
  3883 
  3884 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  3885 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  3886 achieve the old behaviour.
  3887 
  3888 * Pure: the "Goal" constant is now called "prop", supporting a
  3889 slightly more general idea of ``protecting'' meta-level rule
  3890 statements.
  3891 
  3892 * Pure: Logic.(un)varify only works in a global context, which is now
  3893 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  3894 Logic.legacy_(un)varify as temporary workaround.
  3895 
  3896 * Pure: structure Name provides scalable operations for generating
  3897 internal variable names, notably Name.variants etc.  This replaces
  3898 some popular functions from term.ML:
  3899 
  3900   Term.variant		->  Name.variant
  3901   Term.variantlist	->  Name.variant_list
  3902   Term.invent_names	->  Name.invent_list
  3903 
  3904 Note that low-level renaming rarely occurs in new code -- operations
  3905 from structure Variable are used instead (see below).
  3906 
  3907 * Pure: structure Variable provides fundamental operations for proper
  3908 treatment of fixed/schematic variables in a context.  For example,
  3909 Variable.import introduces fixes for schematics of given facts and
  3910 Variable.export reverses the effect (up to renaming) -- this replaces
  3911 various freeze_thaw operations.
  3912 
  3913 * Pure: structure Goal provides simple interfaces for
  3914 init/conclude/finish and tactical prove operations (replacing former
  3915 Tactic.prove).  Goal.prove is the canonical way to prove results
  3916 within a given context; Goal.prove_global is a degraded version for
  3917 theory level goals, including a global Drule.standard.  Note that
  3918 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  3919 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  3920 in a locale context).
  3921 
  3922 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  3923 and type checking (Syntax.check_term etc.), with common combinations
  3924 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  3925 which are considered legacy and await removal.
  3926 
  3927 * Pure/Syntax: generic interfaces for type unchecking
  3928 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  3929 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  3930 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  3931 available for convenience, but refer to the very same operations using
  3932 a mere theory instead of a full context.
  3933 
  3934 * Isar: simplified treatment of user-level errors, using exception
  3935 ERROR of string uniformly.  Function error now merely raises ERROR,
  3936 without any side effect on output channels.  The Isar toplevel takes
  3937 care of proper display of ERROR exceptions.  ML code may use plain
  3938 handle/can/try; cat_error may be used to concatenate errors like this:
  3939 
  3940   ... handle ERROR msg => cat_error msg "..."
  3941 
  3942 Toplevel ML code (run directly or through the Isar toplevel) may be
  3943 embedded into the Isar toplevel with exception display/debug like
  3944 this:
  3945 
  3946   Isar.toplevel (fn () => ...)
  3947 
  3948 INCOMPATIBILITY, removed special transform_error facilities, removed
  3949 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  3950 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  3951 -- use plain ERROR instead.
  3952 
  3953 * Isar: theory setup now has type (theory -> theory), instead of a
  3954 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  3955 
  3956 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  3957 ProofContext.debug/verbose flags.
  3958 
  3959 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  3960 theory before entering a proof state.  Transactions now always see a
  3961 quasi-functional intermediate checkpoint, both in interactive and
  3962 batch mode.
  3963 
  3964 * Isar: simplified interfaces for outer syntax.  Renamed
  3965 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  3966 OuterSyntax.add_parsers -- this functionality is now included in
  3967 OuterSyntax.command etc.  INCOMPATIBILITY.
  3968 
  3969 * Simplifier: the simpset of a running simplification process now
  3970 contains a proof context (cf. Simplifier.the_context), which is the
  3971 very context that the initial simpset has been retrieved from (by
  3972 simpset_of/local_simpset_of).  Consequently, all plug-in components
  3973 (solver, looper etc.) may depend on arbitrary proof data.
  3974 
  3975 * Simplifier.inherit_context inherits the proof context (plus the
  3976 local bounds) of the current simplification process; any simproc
  3977 etc. that calls the Simplifier recursively should do this!  Removed
  3978 former Simplifier.inherit_bounds, which is already included here --
  3979 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  3980 specify an explicit context using Simplifier.context/theory_context.
  3981 
  3982 * Simplifier/Classical Reasoner: more abstract interfaces
  3983 change_simpset/claset for modifying the simpset/claset reference of a
  3984 theory; raw versions simpset/claset_ref etc. have been discontinued --
  3985 INCOMPATIBILITY.
  3986 
  3987 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  3988 "Trueprop" etc.
  3989 
  3990 
  3991 *** System ***
  3992 
  3993 * settings: the default heap location within ISABELLE_HOME_USER now
  3994 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  3995 Isabelle installations.
  3996 
  3997 * isabelle-process: option -S (secure mode) disables some critical
  3998 operations, notably runtime compilation and evaluation of ML source
  3999 code.
  4000 
  4001 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4002 
  4003 * Support for parallel execution, using native multicore support of
  4004 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4005 independent theories, according to the given theory header
  4006 specifications. The maximum number of worker threads is specified via
  4007 usedir option -M or the "max-threads" setting in Proof General. A
  4008 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4009 to 6 on a 8-core machine.  User-code needs to observe certain
  4010 guidelines for thread-safe programming, see appendix A in the Isar
  4011 Implementation manual.
  4012 
  4013 
  4014 
  4015 New in Isabelle2005 (October 2005)
  4016 ----------------------------------
  4017 
  4018 *** General ***
  4019 
  4020 * Theory headers: the new header syntax for Isar theories is
  4021 
  4022   theory <name>
  4023   imports <theory1> ... <theoryN>
  4024   uses <file1> ... <fileM>
  4025   begin
  4026 
  4027 where the 'uses' part is optional.  The previous syntax
  4028 
  4029   theory <name> = <theory1> + ... + <theoryN>:
  4030 
  4031 will disappear in the next release.  Use isatool fixheaders to convert
  4032 existing theory files.  Note that there is no change in ancient
  4033 non-Isar theories now, but these will disappear soon.
  4034 
  4035 * Theory loader: parent theories can now also be referred to via
  4036 relative and absolute paths.
  4037 
  4038 * Command 'find_theorems' searches for a list of criteria instead of a
  4039 list of constants. Known criteria are: intro, elim, dest, name:string,
  4040 simp:term, and any term. Criteria can be preceded by '-' to select
  4041 theorems that do not match. Intro, elim, dest select theorems that
  4042 match the current goal, name:s selects theorems whose fully qualified
  4043 name contain s, and simp:term selects all simplification rules whose
  4044 lhs match term.  Any other term is interpreted as pattern and selects
  4045 all theorems matching the pattern. Available in ProofGeneral under
  4046 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4047 
  4048   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4049 
  4050 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4051 matching the current goal as introduction rule and not having "HOL."
  4052 in their name (i.e. not being defined in theory HOL).
  4053 
  4054 * Command 'thms_containing' has been discontinued in favour of
  4055 'find_theorems'; INCOMPATIBILITY.
  4056 
  4057 * Communication with Proof General is now 8bit clean, which means that
  4058 Unicode text in UTF-8 encoding may be used within theory texts (both
  4059 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4060 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4061 
  4062   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4063   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4064 
  4065 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4066 Classical Reasoner.  Typical big applications run around 2 times
  4067 faster.
  4068 
  4069 
  4070 *** Document preparation ***
  4071 
  4072 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4073 of raw sources.  Only those symbols that do not require additional
  4074 LaTeX packages (depending on comments in isabellesym.sty) are
  4075 displayed properly, everything else is left verbatim.  isatool display
  4076 and isatool print are used as front ends (these are subject to the
  4077 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4078 
  4079 * Command tags control specific markup of certain regions of text,
  4080 notably folding and hiding.  Predefined tags include "theory" (for
  4081 theory begin and end), "proof" for proof commands, and "ML" for
  4082 commands involving ML code; the additional tags "visible" and
  4083 "invisible" are unused by default.  Users may give explicit tag
  4084 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4085 interpretation of tags is determined by the LaTeX job during document
  4086 preparation: see option -V of isatool usedir, or options -n and -t of
  4087 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4088 \isadroptag.
  4089 
  4090 Several document versions may be produced at the same time via isatool
  4091 usedir (the generated index.html will link all of them).  Typical
  4092 specifications include ''-V document=theory,proof,ML'' to present
  4093 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4094 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4095 these parts without any formal replacement text.  The Isabelle site
  4096 default settings produce ''document'' and ''outline'' versions as
  4097 specified above.
  4098 
  4099 * Several new antiquotations:
  4100 
  4101   @{term_type term} prints a term with its type annotated;
  4102 
  4103   @{typeof term} prints the type of a term;
  4104 
  4105   @{const const} is the same as @{term const}, but checks that the
  4106   argument is a known logical constant;
  4107 
  4108   @{term_style style term} and @{thm_style style thm} print a term or
  4109   theorem applying a "style" to it
  4110 
  4111   @{ML text}
  4112 
  4113 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4114 definitions, equations, inequations etc., 'concl' printing only the
  4115 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4116 to print the specified premise.  TermStyle.add_style provides an ML
  4117 interface for introducing further styles.  See also the "LaTeX Sugar"
  4118 document practical applications.  The ML antiquotation prints
  4119 type-checked ML expressions verbatim.
  4120 
  4121 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4122 and 'text' support optional locale specification '(in loc)', which
  4123 specifies the default context for interpreting antiquotations.  For
  4124 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4125 
  4126 * Option 'locale=NAME' of antiquotations specifies an alternative
  4127 context interpreting the subsequent argument.  For example: @{thm
  4128 [locale=lattice] inf_assoc}.
  4129 
  4130 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4131 a proof context.
  4132 
  4133 * Proper output of antiquotations for theory commands involving a
  4134 proof context (such as 'locale' or 'theorem (in loc) ...').
  4135 
  4136 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4137 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4138 
  4139 * isatool usedir: new option -C (default true) controls whether option
  4140 -D should include a copy of the original document directory; -C false
  4141 prevents unwanted effects such as copying of administrative CVS data.
  4142 
  4143 
  4144 *** Pure ***
  4145 
  4146 * Considerably improved version of 'constdefs' command.  Now performs
  4147 automatic type-inference of declared constants; additional support for
  4148 local structure declarations (cf. locales and HOL records), see also
  4149 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4150 sequential dependencies of definitions within a single 'constdefs'
  4151 section; moreover, the declared name needs to be an identifier.  If
  4152 all fails, consider to fall back on 'consts' and 'defs' separately.
  4153 
  4154 * Improved indexed syntax and implicit structures.  First of all,
  4155 indexed syntax provides a notational device for subscripted
  4156 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4157 expressions.  Secondly, in a local context with structure
  4158 declarations, number indexes \<^sub>n or the empty index (default
  4159 number 1) refer to a certain fixed variable implicitly; option
  4160 show_structs controls printing of implicit structures.  Typical
  4161 applications of these concepts involve record types and locales.
  4162 
  4163 * New command 'no_syntax' removes grammar declarations (and
  4164 translations) resulting from the given syntax specification, which is
  4165 interpreted in the same manner as for the 'syntax' command.
  4166 
  4167 * 'Advanced' translation functions (parse_translation etc.) may depend
  4168 on the signature of the theory context being presently used for
  4169 parsing/printing, see also isar-ref manual.
  4170 
  4171 * Improved 'oracle' command provides a type-safe interface to turn an
  4172 ML expression of type theory -> T -> term into a primitive rule of
  4173 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4174 is already included here); see also FOL/ex/IffExample.thy;
  4175 INCOMPATIBILITY.
  4176 
  4177 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4178 before); "cI" is no longer bound, use "c.intro" instead.
  4179 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4180 axclasses vs. locales.
  4181 
  4182 * Improved internal renaming of symbolic identifiers -- attach primes
  4183 instead of base 26 numbers.
  4184 
  4185 * New flag show_question_marks controls printing of leading question
  4186 marks in schematic variable names.
  4187 
  4188 * In schematic variable names, *any* symbol following \<^isub> or
  4189 \<^isup> is now treated as part of the base name.  For example, the
  4190 following works without printing of awkward ".0" indexes:
  4191 
  4192   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4193     by simp
  4194 
  4195 * Inner syntax includes (*(*nested*) comments*).
  4196 
  4197 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4198 annotations as "(00...)".
  4199 
  4200 * Clear separation of logical types and nonterminals, where the latter
  4201 may only occur in 'syntax' specifications or type abbreviations.
  4202 Before that distinction was only partially implemented via type class
  4203 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4204 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4205 exotic syntax specifications may require further adaption
  4206 (e.g. Cube/Cube.thy).
  4207 
  4208 * Removed obsolete type class "logic", use the top sort {} instead.
  4209 Note that non-logical types should be declared as 'nonterminals'
  4210 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4211 specifications.
  4212 
  4213 * Attributes 'induct' and 'cases': type or set names may now be
  4214 locally fixed variables as well.
  4215 
  4216 * Simplifier: can now control the depth to which conditional rewriting
  4217 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4218 Limit.
  4219 
  4220 * Simplifier: simplification procedures may now take the current
  4221 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4222 interface), which is very useful for calling the Simplifier
  4223 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4224 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4225 low-level mk_simproc no longer applies Logic.varify internally, to
  4226 allow for use in a context of fixed variables.
  4227 
  4228 * thin_tac now works even if the assumption being deleted contains !!
  4229 or ==>.  More generally, erule now works even if the major premise of
  4230 the elimination rule contains !! or ==>.
  4231 
  4232 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4233 
  4234 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4235 from Pure, which contains all common declarations already.  Both
  4236 theories are defined via plain Isabelle/Isar .thy files.
  4237 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4238 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4239 use isatool fixcpure to adapt your theory and ML sources.
  4240 
  4241 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4242 selections of theorems in named facts via index ranges.
  4243 
  4244 * 'print_theorems': in theory mode, really print the difference
  4245 wrt. the last state (works for interactive theory development only),
  4246 in proof mode print all local facts (cf. 'print_facts');
  4247 
  4248 * 'hide': option '(open)' hides only base names.
  4249 
  4250 * More efficient treatment of intermediate checkpoints in interactive
  4251 theory development.
  4252 
  4253 * Code generator is now invoked via code_module (incremental code
  4254 generation) and code_library (modular code generation, ML structures
  4255 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4256 must be quoted when used as identifiers.
  4257 
  4258 * New 'value' command for reading, evaluating and printing terms using
  4259 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4260 quoted when used as identifier.
  4261 
  4262 
  4263 *** Locales ***
  4264 
  4265 * New commands for the interpretation of locale expressions in
  4266 theories (1), locales (2) and proof contexts (3).  These generate
  4267 proof obligations from the expression specification.  After the
  4268 obligations have been discharged, theorems of the expression are added
  4269 to the theory, target locale or proof context.  The synopsis of the
  4270 commands is a follows:
  4271 
  4272   (1) interpretation expr inst
  4273   (2) interpretation target < expr
  4274   (3) interpret expr inst
  4275 
  4276 Interpretation in theories and proof contexts require a parameter
  4277 instantiation of terms from the current context.  This is applied to
  4278 specifications and theorems of the interpreted expression.
  4279 Interpretation in locales only permits parameter renaming through the
  4280 locale expression.  Interpretation is smart in that interpretations
  4281 that are active already do not occur in proof obligations, neither are
  4282 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4283 inspect active interpretations of a particular locale.  For details,
  4284 see the Isar Reference manual.  Examples can be found in
  4285 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4286 
  4287 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4288 'interpret' instead.
  4289 
  4290 * New context element 'constrains' for adding type constraints to
  4291 parameters.
  4292 
  4293 * Context expressions: renaming of parameters with syntax
  4294 redeclaration.
  4295 
  4296 * Locale declaration: 'includes' disallowed.
  4297 
  4298 * Proper static binding of attribute syntax -- i.e. types / terms /
  4299 facts mentioned as arguments are always those of the locale definition
  4300 context, independently of the context of later invocations.  Moreover,
  4301 locale operations (renaming and type / term instantiation) are applied
  4302 to attribute arguments as expected.
  4303 
  4304 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4305 actual attributes; rare situations may require Attrib.attribute to
  4306 embed those attributes into Attrib.src that lack concrete syntax.
  4307 Attribute implementations need to cooperate properly with the static
  4308 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4309 Attrib.XXX_thm etc. already do the right thing without further
  4310 intervention.  Only unusual applications -- such as "where" or "of"
  4311 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4312 on the context and the facts involved -- may have to assign parsed
  4313 values to argument tokens explicitly.
  4314 
  4315 * Changed parameter management in theorem generation for long goal
  4316 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4317 theorem statement in rare situations.
  4318 
  4319 * Locale inspection command 'print_locale' omits notes elements.  Use
  4320 'print_locale!' to have them included in the output.
  4321 
  4322 
  4323 *** Provers ***
  4324 
  4325 * Provers/hypsubst.ML: improved version of the subst method, for
  4326 single-step rewriting: it now works in bound variable contexts. New is
  4327 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4328 rewrite a different subterm than the original subst method, which is
  4329 still available as 'simplesubst'.
  4330 
  4331 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4332 and quasi orders.
  4333 
  4334 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4335 reflexive-transitive closure of relations.
  4336 
  4337 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4338 limit (previously hard-coded with a value of 20) user-definable.
  4339 
  4340 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4341 is peformed already.  Object-logics merely need to finish their
  4342 initial simpset configuration as before.  INCOMPATIBILITY.
  4343 
  4344 
  4345 *** HOL ***
  4346 
  4347 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4348 
  4349   syntax (epsilon)
  4350     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4351 
  4352 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4353 and x-symbol; use option '-m epsilon' to get it actually printed.
  4354 Moreover, the mathematically important symbolic identifier \<epsilon>
  4355 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4356 
  4357 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  4358 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  4359 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  4360 support corresponding Isar calculations.
  4361 
  4362 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  4363 instead of ":".
  4364 
  4365 * theory SetInterval: changed the syntax for open intervals:
  4366 
  4367   Old       New
  4368   {..n(}    {..<n}
  4369   {)n..}    {n<..}
  4370   {m..n(}   {m..<n}
  4371   {)m..n}   {m<..n}
  4372   {)m..n(}  {m<..<n}
  4373 
  4374 The old syntax is still supported but will disappear in the next
  4375 release.  For conversion use the following Emacs search and replace
  4376 patterns (these are not perfect but work quite well):
  4377 
  4378   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  4379   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  4380 
  4381 * Theory Commutative_Ring (in Library): method comm_ring for proving
  4382 equalities in commutative rings; method 'algebra' provides a generic
  4383 interface.
  4384 
  4385 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  4386 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  4387 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  4388 be a tuple pattern.
  4389 
  4390 Some new syntax forms are available:
  4391 
  4392   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  4393   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  4394   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  4395   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  4396 
  4397 The latter form "\<Sum>x < k. e" used to be based on a separate
  4398 function "Summation", which has been discontinued.
  4399 
  4400 * theory Finite_Set: in structured induction proofs, the insert case
  4401 is now 'case (insert x F)' instead of the old counterintuitive 'case
  4402 (insert F x)'.
  4403 
  4404 * The 'refute' command has been extended to support a much larger
  4405 fragment of HOL, including axiomatic type classes, constdefs and
  4406 typedefs, inductive datatypes and recursion.
  4407 
  4408 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  4409 Requires zChaff with proof generation to be installed.  See
  4410 HOL/ex/SAT_Examples.thy for examples.
  4411 
  4412 * Datatype induction via method 'induct' now preserves the name of the
  4413 induction variable. For example, when proving P(xs::'a list) by
  4414 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  4415 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  4416 in unstructured proof scripts.
  4417 
  4418 * Reworked implementation of records.  Improved scalability for
  4419 records with many fields, avoiding performance problems for type
  4420 inference. Records are no longer composed of nested field types, but
  4421 of nested extension types. Therefore the record type only grows linear
  4422 in the number of extensions and not in the number of fields.  The
  4423 top-level (users) view on records is preserved.  Potential
  4424 INCOMPATIBILITY only in strange cases, where the theory depends on the
  4425 old record representation. The type generated for a record is called
  4426 <record_name>_ext_type.
  4427 
  4428 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  4429 proofs triggered by a record definition or a simproc (if
  4430 quick_and_dirty is enabled).  Definitions of large records can take
  4431 quite long.
  4432 
  4433 New simproc record_upd_simproc for simplification of multiple record
  4434 updates enabled by default.  Moreover, trivial updates are also
  4435 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  4436 occasionally, since simplification is more powerful by default.
  4437 
  4438 * typedef: proper support for polymorphic sets, which contain extra
  4439 type-variables in the term.
  4440 
  4441 * Simplifier: automatically reasons about transitivity chains
  4442 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  4443 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  4444 old proofs break occasionally as simplification may now solve more
  4445 goals than previously.
  4446 
  4447 * Simplifier: converts x <= y into x = y if assumption y <= x is
  4448 present.  Works for all partial orders (class "order"), in particular
  4449 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  4450 just like y <= x.
  4451 
  4452 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  4453 bound variable or a constant then the let is unfolded.  Otherwise
  4454 first a is simplified to b, and then f b is simplified to g. If
  4455 possible we abstract b from g arriving at "let x = b in h x",
  4456 otherwise we unfold the let and arrive at g.  The simproc can be
  4457 enabled/disabled by the reference use_let_simproc.  Potential
  4458 INCOMPATIBILITY since simplification is more powerful by default.
  4459 
  4460 * Classical reasoning: the meson method now accepts theorems as arguments.
  4461 
  4462 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  4463 jobs to provide advice on the provability of subgoals.
  4464 
  4465 * Theory OrderedGroup and Ring_and_Field: various additions and
  4466 improvements to faciliate calculations involving equalities and
  4467 inequalities.
  4468 
  4469 The following theorems have been eliminated or modified
  4470 (INCOMPATIBILITY):
  4471 
  4472   abs_eq             now named abs_of_nonneg
  4473   abs_of_ge_0        now named abs_of_nonneg
  4474   abs_minus_eq       now named abs_of_nonpos
  4475   imp_abs_id         now named abs_of_nonneg
  4476   imp_abs_neg_id     now named abs_of_nonpos
  4477   mult_pos           now named mult_pos_pos
  4478   mult_pos_le        now named mult_nonneg_nonneg
  4479   mult_pos_neg_le    now named mult_nonneg_nonpos
  4480   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  4481   mult_neg           now named mult_neg_neg
  4482   mult_neg_le        now named mult_nonpos_nonpos
  4483 
  4484 * The following lemmas in Ring_and_Field have been added to the simplifier:
  4485      
  4486      zero_le_square
  4487      not_square_less_zero 
  4488 
  4489   The following lemmas have been deleted from Real/RealPow:
  4490   
  4491      realpow_zero_zero
  4492      realpow_two
  4493      realpow_less
  4494      zero_le_power
  4495      realpow_two_le
  4496      abs_realpow_two
  4497      realpow_two_abs     
  4498 
  4499 * Theory Parity: added rules for simplifying exponents.
  4500 
  4501 * Theory List:
  4502 
  4503 The following theorems have been eliminated or modified
  4504 (INCOMPATIBILITY):
  4505 
  4506   list_all_Nil       now named list_all.simps(1)
  4507   list_all_Cons      now named list_all.simps(2)
  4508   list_all_conv      now named list_all_iff
  4509   set_mem_eq         now named mem_iff
  4510 
  4511 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  4512 asymptotic "big O" calculations.  See the notes in BigO.thy.
  4513 
  4514 
  4515 *** HOL-Complex ***
  4516 
  4517 * Theory RealDef: better support for embedding natural numbers and
  4518 integers in the reals.
  4519 
  4520 The following theorems have been eliminated or modified
  4521 (INCOMPATIBILITY):
  4522 
  4523   exp_ge_add_one_self  now requires no hypotheses
  4524   real_of_int_add      reversed direction of equality (use [symmetric])
  4525   real_of_int_minus    reversed direction of equality (use [symmetric])
  4526   real_of_int_diff     reversed direction of equality (use [symmetric])
  4527   real_of_int_mult     reversed direction of equality (use [symmetric])
  4528 
  4529 * Theory RComplete: expanded support for floor and ceiling functions.
  4530 
  4531 * Theory Ln is new, with properties of the natural logarithm
  4532 
  4533 * Hyperreal: There is a new type constructor "star" for making
  4534 nonstandard types.  The old type names are now type synonyms:
  4535 
  4536   hypreal = real star
  4537   hypnat = nat star
  4538   hcomplex = complex star
  4539 
  4540 * Hyperreal: Many groups of similarly-defined constants have been
  4541 replaced by polymorphic versions (INCOMPATIBILITY):
  4542 
  4543   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  4544 
  4545   starset      <-- starsetNat, starsetC
  4546   *s*          <-- *sNat*, *sc*
  4547   starset_n    <-- starsetNat_n, starsetC_n
  4548   *sn*         <-- *sNatn*, *scn*
  4549   InternalSets <-- InternalNatSets, InternalCSets
  4550 
  4551   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  4552   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  4553   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  4554   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  4555   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  4556 
  4557 * Hyperreal: Many type-specific theorems have been removed in favor of
  4558 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  4559 
  4560   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  4561   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  4562   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  4563   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  4564   right_minus <-- hypreal_add_minus
  4565   left_minus <-- {hypreal,hcomplex}_add_minus_left
  4566   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  4567   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  4568   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  4569   mult_1_right <-- hcomplex_mult_one_right
  4570   mult_zero_left <-- hcomplex_mult_zero_left
  4571   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  4572   right_distrib <-- hypnat_add_mult_distrib2
  4573   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  4574   right_inverse <-- hypreal_mult_inverse
  4575   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  4576   order_refl <-- {hypreal,hypnat}_le_refl
  4577   order_trans <-- {hypreal,hypnat}_le_trans
  4578   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  4579   order_less_le <-- {hypreal,hypnat}_less_le
  4580   linorder_linear <-- {hypreal,hypnat}_le_linear
  4581   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  4582   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  4583   add_nonneg_nonneg <-- hypreal_le_add_order
  4584 
  4585 * Hyperreal: Separate theorems having to do with type-specific
  4586 versions of constants have been merged into theorems that apply to the
  4587 new polymorphic constants (INCOMPATIBILITY):
  4588 
  4589   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  4590   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  4591   STAR_Un <-- {STAR,NatStar,STARC}_Un
  4592   STAR_Int <-- {STAR,NatStar,STARC}_Int
  4593   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  4594   STAR_subset <-- {STAR,NatStar,STARC}_subset
  4595   STAR_mem <-- {STAR,NatStar,STARC}_mem
  4596   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  4597   STAR_diff <-- {STAR,STARC}_diff
  4598   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  4599     STARC_hcomplex_of_complex}_image_subset
  4600   starset_n_Un <-- starset{Nat,C}_n_Un
  4601   starset_n_Int <-- starset{Nat,C}_n_Int
  4602   starset_n_Compl <-- starset{Nat,C}_n_Compl
  4603   starset_n_diff <-- starset{Nat,C}_n_diff
  4604   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  4605   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  4606   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  4607   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  4608   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  4609   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  4610   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  4611   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  4612   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  4613   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  4614   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  4615   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  4616   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  4617   starfun_diff <-- starfun{C,RC,CR}_diff
  4618   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  4619   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  4620   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  4621   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  4622   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  4623   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  4624   starfun_Id <-- starfunC_Id
  4625   starfun_approx <-- starfun{Nat,CR}_approx
  4626   starfun_capprox <-- starfun{C,RC}_capprox
  4627   starfun_abs <-- starfunNat_rabs
  4628   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  4629   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  4630   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  4631   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  4632   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  4633   starfun_add_approx <-- starfunCR_add_approx
  4634   starfun_inverse_inverse <-- starfunC_inverse_inverse
  4635   starfun_divide <-- starfun{C,CR,RC}_divide
  4636   starfun_n <-- starfun{Nat,C}_n
  4637   starfun_n_mult <-- starfun{Nat,C}_n_mult
  4638   starfun_n_add <-- starfun{Nat,C}_n_add
  4639   starfun_n_add_minus <-- starfunNat_n_add_minus
  4640   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  4641   starfun_n_minus <-- starfun{Nat,C}_n_minus
  4642   starfun_n_eq <-- starfun{Nat,C}_n_eq
  4643 
  4644   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  4645   star_n_minus <-- {hypreal,hcomplex}_minus
  4646   star_n_diff <-- {hypreal,hcomplex}_diff
  4647   star_n_mult <-- {hypreal,hcomplex}_mult
  4648   star_n_inverse <-- {hypreal,hcomplex}_inverse
  4649   star_n_le <-- {hypreal,hypnat}_le
  4650   star_n_less <-- {hypreal,hypnat}_less
  4651   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  4652   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  4653   star_n_abs <-- hypreal_hrabs
  4654   star_n_divide <-- hcomplex_divide
  4655 
  4656   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  4657   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  4658   star_of_diff <-- hypreal_of_real_diff
  4659   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  4660   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  4661   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  4662   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  4663   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  4664   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  4665   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  4666   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  4667   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  4668   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  4669   star_of_number_of <-- {hypreal,hcomplex}_number_of
  4670   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  4671   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  4672   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  4673   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  4674   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  4675   star_of_power <-- hypreal_of_real_power
  4676   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  4677 
  4678 * Hyperreal: new method "transfer" that implements the transfer
  4679 principle of nonstandard analysis. With a subgoal that mentions
  4680 nonstandard types like "'a star", the command "apply transfer"
  4681 replaces it with an equivalent one that mentions only standard types.
  4682 To be successful, all free variables must have standard types; non-
  4683 standard variables must have explicit universal quantifiers.
  4684 
  4685 * Hyperreal: A theory of Taylor series.
  4686 
  4687 
  4688 *** HOLCF ***
  4689 
  4690 * Discontinued special version of 'constdefs' (which used to support
  4691 continuous functions) in favor of the general Pure one with full
  4692 type-inference.
  4693 
  4694 * New simplification procedure for solving continuity conditions; it
  4695 is much faster on terms with many nested lambda abstractions (cubic
  4696 instead of exponential time).
  4697 
  4698 * New syntax for domain package: selector names are now optional.
  4699 Parentheses should be omitted unless argument is lazy, for example:
  4700 
  4701   domain 'a stream = cons "'a" (lazy "'a stream")
  4702 
  4703 * New command 'fixrec' for defining recursive functions with pattern
  4704 matching; defining multiple functions with mutual recursion is also
  4705 supported.  Patterns may include the constants cpair, spair, up, sinl,
  4706 sinr, or any data constructor defined by the domain package. The given
  4707 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  4708 syntax and examples.
  4709 
  4710 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  4711 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  4712 but the proof obligation additionally includes an admissibility
  4713 requirement. The packages generate instances of class cpo or pcpo,
  4714 with continuity and strictness theorems for Rep and Abs.
  4715 
  4716 * HOLCF: Many theorems have been renamed according to a more standard naming
  4717 scheme (INCOMPATIBILITY):
  4718 
  4719   foo_inject:  "foo$x = foo$y ==> x = y"
  4720   foo_eq:      "(foo$x = foo$y) = (x = y)"
  4721   foo_less:    "(foo$x << foo$y) = (x << y)"
  4722   foo_strict:  "foo$UU = UU"
  4723   foo_defined: "... ==> foo$x ~= UU"
  4724   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  4725 
  4726 
  4727 *** ZF ***
  4728 
  4729 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  4730 including the First Isomorphism Theorem (on quotienting by the kernel
  4731 of a homomorphism).
  4732 
  4733 * ZF/Simplifier: install second copy of type solver that actually
  4734 makes use of TC rules declared to Isar proof contexts (or locales);
  4735 the old version is still required for ML proof scripts.
  4736 
  4737 
  4738 *** Cube ***
  4739 
  4740 * Converted to Isar theory format; use locales instead of axiomatic
  4741 theories.
  4742 
  4743 
  4744 *** ML ***
  4745 
  4746 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  4747 for ||>, ||>>, |>>,
  4748 
  4749 * Pure/library.ML no longer defines its own option datatype, but uses
  4750 that of the SML basis, which has constructors NONE and SOME instead of
  4751 None and Some, as well as exception Option.Option instead of OPTION.
  4752 The functions the, if_none, is_some, is_none have been adapted
  4753 accordingly, while Option.map replaces apsome.
  4754 
  4755 * Pure/library.ML: the exception LIST has been given up in favour of
  4756 the standard exceptions Empty and Subscript, as well as
  4757 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  4758 superceded by the standard hd and tl functions etc.
  4759 
  4760 A number of basic list functions are no longer exported to the ML
  4761 toplevel, as they are variants of predefined functions.  The following
  4762 suggests how one can translate existing code:
  4763 
  4764     rev_append xs ys = List.revAppend (xs, ys)
  4765     nth_elem (i, xs) = List.nth (xs, i)
  4766     last_elem xs = List.last xs
  4767     flat xss = List.concat xss
  4768     seq fs = List.app fs
  4769     partition P xs = List.partition P xs
  4770     mapfilter f xs = List.mapPartial f xs
  4771 
  4772 * Pure/library.ML: several combinators for linear functional
  4773 transformations, notably reverse application and composition:
  4774 
  4775   x |> f                f #> g
  4776   (x, y) |-> f          f #-> g
  4777 
  4778 * Pure/library.ML: introduced/changed precedence of infix operators:
  4779 
  4780   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  4781   infix 2 ?;
  4782   infix 3 o oo ooo oooo;
  4783   infix 4 ~~ upto downto;
  4784 
  4785 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  4786 infix operators.
  4787 
  4788 * Pure/library.ML: natural list combinators fold, fold_rev, and
  4789 fold_map support linear functional transformations and nesting.  For
  4790 example:
  4791 
  4792   fold f [x1, ..., xN] y =
  4793     y |> f x1 |> ... |> f xN
  4794 
  4795   (fold o fold) f [xs1, ..., xsN] y =
  4796     y |> fold f xs1 |> ... |> fold f xsN
  4797 
  4798   fold f [x1, ..., xN] =
  4799     f x1 #> ... #> f xN
  4800 
  4801   (fold o fold) f [xs1, ..., xsN] =
  4802     fold f xs1 #> ... #> fold f xsN
  4803 
  4804 * Pure/library.ML: the following selectors on type 'a option are
  4805 available:
  4806 
  4807   the:               'a option -> 'a  (*partial*)
  4808   these:             'a option -> 'a  where 'a = 'b list
  4809   the_default: 'a -> 'a option -> 'a
  4810   the_list:          'a option -> 'a list
  4811 
  4812 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  4813 basic operations for association lists, following natural argument
  4814 order; moreover the explicit equality predicate passed here avoids
  4815 potentially expensive polymorphic runtime equality checks.
  4816 The old functions may be expressed as follows:
  4817 
  4818   assoc = uncurry (AList.lookup (op =))
  4819   assocs = these oo AList.lookup (op =)
  4820   overwrite = uncurry (AList.update (op =)) o swap
  4821 
  4822 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  4823 
  4824   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  4825   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  4826 
  4827 replacing make_keylist and keyfilter (occassionally used)
  4828 Naive rewrites:
  4829 
  4830   make_keylist = AList.make
  4831   keyfilter = AList.find (op =)
  4832 
  4833 * eq_fst and eq_snd now take explicit equality parameter, thus
  4834   avoiding eqtypes. Naive rewrites:
  4835 
  4836     eq_fst = eq_fst (op =)
  4837     eq_snd = eq_snd (op =)
  4838 
  4839 * Removed deprecated apl and apr (rarely used).
  4840   Naive rewrites:
  4841 
  4842     apl (n, op) =>>= curry op n
  4843     apr (op, m) =>>= fn n => op (n, m)
  4844 
  4845 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  4846 provides a reasonably efficient light-weight implementation of sets as
  4847 lists.
  4848 
  4849 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  4850 few new operations; existing lookup and update are now curried to
  4851 follow natural argument order (for use with fold etc.);
  4852 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  4853 
  4854 * Pure/General: output via the Isabelle channels of
  4855 writeln/warning/error etc. is now passed through Output.output, with a
  4856 hook for arbitrary transformations depending on the print_mode
  4857 (cf. Output.add_mode -- the first active mode that provides a output
  4858 function wins).  Already formatted output may be embedded into further
  4859 text via Output.raw; the result of Pretty.string_of/str_of and derived
  4860 functions (string_of_term/cterm/thm etc.) is already marked raw to
  4861 accommodate easy composition of diagnostic messages etc.  Programmers
  4862 rarely need to care about Output.output or Output.raw at all, with
  4863 some notable exceptions: Output.output is required when bypassing the
  4864 standard channels (writeln etc.), or in token translations to produce
  4865 properly formatted results; Output.raw is required when capturing
  4866 already output material that will eventually be presented to the user
  4867 a second time.  For the default print mode, both Output.output and
  4868 Output.raw have no effect.
  4869 
  4870 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  4871 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  4872 cumulative results are displayed at the end of a batch session.
  4873 
  4874 * Pure/General: File.sysify_path and File.quote_sysify path have been
  4875 replaced by File.platform_path and File.shell_path (with appropriate
  4876 hooks).  This provides a clean interface for unusual systems where the
  4877 internal and external process view of file names are different.
  4878 
  4879 * Pure: more efficient orders for basic syntactic entities: added
  4880 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  4881 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  4882 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  4883 orders now -- potential INCOMPATIBILITY for code that depends on a
  4884 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  4885 Library.sort_strings on result).
  4886 
  4887 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  4888 fold_types traverse types/terms from left to right, observing natural
  4889 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  4890 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  4891 
  4892 * Pure: name spaces have been refined, with significant changes of the
  4893 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  4894 to extern(_table).  The plain name entry path is superceded by a
  4895 general 'naming' context, which also includes the 'policy' to produce
  4896 a fully qualified name and external accesses of a fully qualified
  4897 name; NameSpace.extend is superceded by context dependent
  4898 Sign.declare_name.  Several theory and proof context operations modify
  4899 the naming context.  Especially note Theory.restore_naming and
  4900 ProofContext.restore_naming to get back to a sane state; note that
  4901 Theory.add_path is no longer sufficient to recover from
  4902 Theory.absolute_path in particular.
  4903 
  4904 * Pure: new flags short_names (default false) and unique_names
  4905 (default true) for controlling output of qualified names.  If
  4906 short_names is set, names are printed unqualified.  If unique_names is
  4907 reset, the name prefix is reduced to the minimum required to achieve
  4908 the original result when interning again, even if there is an overlap
  4909 with earlier declarations.
  4910 
  4911 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  4912 now 'extend', and 'merge' gets an additional Pretty.pp argument
  4913 (useful for printing error messages).  INCOMPATIBILITY.
  4914 
  4915 * Pure: major reorganization of the theory context.  Type Sign.sg and
  4916 Theory.theory are now identified, referring to the universal
  4917 Context.theory (see Pure/context.ML).  Actual signature and theory
  4918 content is managed as theory data.  The old code and interfaces were
  4919 spread over many files and structures; the new arrangement introduces
  4920 considerable INCOMPATIBILITY to gain more clarity:
  4921 
  4922   Context -- theory management operations (name, identity, inclusion,
  4923     parents, ancestors, merge, etc.), plus generic theory data;
  4924 
  4925   Sign -- logical signature and syntax operations (declaring consts,
  4926     types, etc.), plus certify/read for common entities;
  4927 
  4928   Theory -- logical theory operations (stating axioms, definitions,
  4929     oracles), plus a copy of logical signature operations (consts,
  4930     types, etc.); also a few basic management operations (Theory.copy,
  4931     Theory.merge, etc.)
  4932 
  4933 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  4934 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  4935 for convenience -- they merely return the theory.
  4936 
  4937 * Pure: type Type.tsig is superceded by theory in most interfaces.
  4938 
  4939 * Pure: the Isar proof context type is already defined early in Pure
  4940 as Context.proof (note that ProofContext.context and Proof.context are
  4941 aliases, where the latter is the preferred name).  This enables other
  4942 Isabelle components to refer to that type even before Isar is present.
  4943 
  4944 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  4945 typeK, constK, axiomK, oracleK), but provide explicit operations for
  4946 any of these kinds.  For example, Sign.intern typeK is now
  4947 Sign.intern_type, Theory.hide_space Sign.typeK is now
  4948 Theory.hide_types.  Also note that former
  4949 Theory.hide_classes/types/consts are now
  4950 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  4951 internalize their arguments!  INCOMPATIBILITY.
  4952 
  4953 * Pure: get_thm interface (of PureThy and ProofContext) expects
  4954 datatype thmref (with constructors Name and NameSelection) instead of
  4955 plain string -- INCOMPATIBILITY;
  4956 
  4957 * Pure: cases produced by proof methods specify options, where NONE
  4958 means to remove case bindings -- INCOMPATIBILITY in
  4959 (RAW_)METHOD_CASES.
  4960 
  4961 * Pure: the following operations retrieve axioms or theorems from a
  4962 theory node or theory hierarchy, respectively:
  4963 
  4964   Theory.axioms_of: theory -> (string * term) list
  4965   Theory.all_axioms_of: theory -> (string * term) list
  4966   PureThy.thms_of: theory -> (string * thm) list
  4967   PureThy.all_thms_of: theory -> (string * thm) list
  4968 
  4969 * Pure: print_tac now outputs the goal through the trace channel.
  4970 
  4971 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  4972 Reference Toplevel.debug (default false) controls detailed printing
  4973 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  4974 controls execution profiling -- set to 1 for time and 2 for space
  4975 (both increase the runtime).
  4976 
  4977 * Isar session: The initial use of ROOT.ML is now always timed,
  4978 i.e. the log will show the actual process times, in contrast to the
  4979 elapsed wall-clock time that the outer shell wrapper produces.
  4980 
  4981 * Simplifier: improved handling of bound variables (nameless
  4982 representation, avoid allocating new strings).  Simprocs that invoke
  4983 the Simplifier recursively should use Simplifier.inherit_bounds to
  4984 avoid local name clashes.  Failure to do so produces warnings
  4985 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  4986 for further details.
  4987 
  4988 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  4989 bindings for all theorems stored within a given theory; this may help
  4990 in porting non-Isar theories to Isar ones, while keeping ML proof
  4991 scripts for the time being.
  4992 
  4993 * ML operator HTML.with_charset specifies the charset begin used for
  4994 generated HTML files.  For example:
  4995 
  4996   HTML.with_charset "utf-8" use_thy "Hebrew";
  4997   HTML.with_charset "utf-8" use_thy "Chinese";
  4998 
  4999 
  5000 *** System ***
  5001 
  5002 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5003 isabelle, isatool etc.).
  5004 
  5005 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5006 isatool doc, isatool mkdir, display_drafts etc.).
  5007 
  5008 * isatool usedir: option -f allows specification of the ML file to be
  5009 used by Isabelle; default is ROOT.ML.
  5010 
  5011 * New isatool version outputs the version identifier of the Isabelle
  5012 distribution being used.
  5013 
  5014 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5015 (containing Boolean satisfiability problems) into Isabelle/HOL
  5016 theories.
  5017 
  5018 
  5019 
  5020 New in Isabelle2004 (April 2004)
  5021 --------------------------------
  5022 
  5023 *** General ***
  5024 
  5025 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5026   Replaces linorder.ML.
  5027 
  5028 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5029   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5030   (\<a>...\<z>), are now considered normal letters, and can therefore
  5031   be used anywhere where an ASCII letter (a...zA...Z) has until
  5032   now. COMPATIBILITY: This obviously changes the parsing of some
  5033   terms, especially where a symbol has been used as a binder, say
  5034   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5035   as an identifier.  Fix it by inserting a space around former
  5036   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5037   existing theory and ML files.
  5038 
  5039 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5040 
  5041 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5042   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5043   a normal (but invisible) letter. For multiple letter subscripts repeat
  5044   \<^isub> like this: x\<^isub>1\<^isub>2.
  5045 
  5046 * Pure: There are now sub-/superscripts that can span more than one
  5047   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5048   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5049   superscript. The new control characters are not identifier parts.
  5050 
  5051 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5052   content of "..." to the latex file instead of \isacntrl... . The "..."
  5053   may consist of any printable characters excluding the end bracket >.
  5054 
  5055 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5056   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5057   declare constants "final", which prevents their being given a definition
  5058   later.  It is useful for constants whose behaviour is fixed axiomatically
  5059   rather than definitionally, such as the meta-logic connectives.
  5060 
  5061 * Pure: 'instance' now handles general arities with general sorts
  5062   (i.e. intersections of classes),
  5063 
  5064 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5065   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5066   It can be changed to alter the colors/layout of generated pages.
  5067 
  5068 
  5069 *** Isar ***
  5070 
  5071 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5072   cut_tac, subgoal_tac and thin_tac:
  5073   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5074     locales are no longer forced to write Isar proof scripts.
  5075     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5076     emulations.
  5077   - INCOMPATIBILITY: names of variables to be instantiated may no
  5078     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5079     This is consistent with the instantiation attribute "where".
  5080 
  5081 * Attributes "where" and "of":
  5082   - Now take type variables of instantiated theorem into account when reading
  5083     the instantiation string.  This fixes a bug that caused instantiated
  5084     theorems to have too special types in some circumstances.
  5085   - "where" permits explicit instantiations of type variables.
  5086 
  5087 * Calculation commands "moreover" and "also" no longer interfere with
  5088   current facts ("this"), admitting arbitrary combinations with "then"
  5089   and derived forms.
  5090 
  5091 * Locales:
  5092   - Goal statements involving the context element "includes" no longer
  5093     generate theorems with internal delta predicates (those ending on
  5094     "_axioms") in the premise.
  5095     Resolve particular premise with <locale>.intro to obtain old form.
  5096   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5097     specification and "includes" elements in goal statement.
  5098   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5099     [intro?] and [elim?] (respectively) by default.
  5100   - Experimental command for instantiation of locales in proof contexts:
  5101         instantiate <label>[<attrs>]: <loc>
  5102     Instantiates locale <loc> and adds all its theorems to the current context
  5103     taking into account their attributes.  Label and attrs are optional
  5104     modifiers, like in theorem declarations.  If present, names of
  5105     instantiated theorems are qualified with <label>, and the attributes
  5106     <attrs> are applied after any attributes these theorems might have already.
  5107       If the locale has assumptions, a chained fact of the form
  5108     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5109     are derived.  The command does not support old-style locales declared
  5110     with "locale (open)".
  5111       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5112 
  5113 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5114   (Isar) contexts.
  5115 
  5116 
  5117 *** HOL ***
  5118 
  5119 * Proof import: new image HOL4 contains the imported library from
  5120   the HOL4 system with about 2500 theorems. It is imported by
  5121   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5122   can be used like any other Isabelle image.  See
  5123   HOL/Import/HOL/README for more information.
  5124 
  5125 * Simplifier:
  5126   - Much improved handling of linear and partial orders.
  5127     Reasoners for linear and partial orders are set up for type classes
  5128     "linorder" and "order" respectively, and are added to the default simpset
  5129     as solvers.  This means that the simplifier can build transitivity chains
  5130     to solve goals from the assumptions.
  5131   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5132     of blast or auto after simplification become unnecessary because the goal
  5133     is solved by simplification already.
  5134 
  5135 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5136     all proved in axiomatic type classes for semirings, rings and fields.
  5137 
  5138 * Numerics:
  5139   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5140     now formalized using the Ring_and_Field theory mentioned above.
  5141   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5142     than before, because now they are set up once in a generic manner.
  5143   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5144     Look for the general versions in Ring_and_Field (and Power if they concern
  5145     exponentiation).
  5146 
  5147 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5148 
  5149 * Records:
  5150   - Record types are now by default printed with their type abbreviation
  5151     instead of the list of all field types. This can be configured via
  5152     the reference "print_record_type_abbr".
  5153   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5154     (not enabled by default).
  5155   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5156     EX x. x = sel r to True (not enabled by default).
  5157   - Tactic "record_split_simp_tac" to split and simplify records added.
  5158 
  5159 * 'specification' command added, allowing for definition by
  5160   specification.  There is also an 'ax_specification' command that
  5161   introduces the new constants axiomatically.
  5162 
  5163 * arith(_tac) is now able to generate counterexamples for reals as well.
  5164 
  5165 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5166 
  5167 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5168   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5169 
  5170 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5171   matrix theory to linear programming.
  5172 
  5173 * Unions and Intersections:
  5174   The latex output syntax of UN and INT has been changed
  5175   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5176   i.e. the index formulae has become a subscript.
  5177   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5178 
  5179 * Unions and Intersections over Intervals:
  5180   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5181   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5182   like in normal math, and corresponding versions for < and for intersection.
  5183 
  5184 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5185   lexicographic dictonary ordering has been added as "lexord".
  5186 
  5187 * ML: the legacy theory structures Int and List have been removed. They had
  5188   conflicted with ML Basis Library structures having the same names.
  5189 
  5190 * 'refute' command added to search for (finite) countermodels.  Only works
  5191   for a fragment of HOL.  The installation of an external SAT solver is
  5192   highly recommended.  See "HOL/Refute.thy" for details.
  5193 
  5194 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5195   formulae under an assignment of free variables to random values.
  5196   In contrast to 'refute', it can deal with inductive datatypes,
  5197   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5198   for examples.
  5199 
  5200 
  5201 *** HOLCF ***
  5202 
  5203 * Streams now come with concatenation and are part of the HOLCF image
  5204 
  5205 
  5206 
  5207 New in Isabelle2003 (May 2003)
  5208 ------------------------------
  5209 
  5210 *** General ***
  5211 
  5212 * Provers/simplifier:
  5213 
  5214   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5215     Assumptions are now subject to complete mutual simplification,
  5216     not just from left to right. The simplifier now preserves
  5217     the order of assumptions.
  5218 
  5219     Potential INCOMPATIBILITY:
  5220 
  5221     -- simp sometimes diverges where the old version did
  5222        not, e.g. invoking simp on the goal
  5223 
  5224         [| P (f x); y = x; f x = f y |] ==> Q
  5225 
  5226        now gives rise to the infinite reduction sequence
  5227 
  5228         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5229 
  5230        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5231        kind of problem.
  5232 
  5233     -- Tactics combining classical reasoner and simplification (such as auto)
  5234        are also affected by this change, because many of them rely on
  5235        simp. They may sometimes diverge as well or yield a different numbers
  5236        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5237        in case of problems. Sometimes subsequent calls to the classical
  5238        reasoner will fail because a preceeding call to the simplifier too
  5239        eagerly simplified the goal, e.g. deleted redundant premises.
  5240 
  5241   - The simplifier trace now shows the names of the applied rewrite rules
  5242 
  5243   - You can limit the number of recursive invocations of the simplifier
  5244     during conditional rewriting (where the simplifie tries to solve the
  5245     conditions before applying the rewrite rule):
  5246     ML "simp_depth_limit := n"
  5247     where n is an integer. Thus you can force termination where previously
  5248     the simplifier would diverge.
  5249 
  5250   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5251 
  5252   - No longer aborts on failed congruence proof.  Instead, the
  5253     congruence is ignored.
  5254 
  5255 * Pure: New generic framework for extracting programs from constructive
  5256   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5257   as HOL/Extraction for some case studies.
  5258 
  5259 * Pure: The main goal of the proof state is no longer shown by default, only
  5260 the subgoals. This behaviour is controlled by a new flag.
  5261    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5262 (ML: Proof.show_main_goal).
  5263 
  5264 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5265 rules whose conclusion matches subgoal 1:
  5266       PG menu: Isabelle/Isar -> Show me -> matching rules
  5267 The rules are ordered by how closely they match the subgoal.
  5268 In particular, rules that solve a subgoal outright are displayed first
  5269 (or rather last, the way they are printed).
  5270 (ML: ProofGeneral.print_intros())
  5271 
  5272 * Pure: New flag trace_unify_fail causes unification to print
  5273 diagnostic information (PG: in trace buffer) when it fails. This is
  5274 useful for figuring out why single step proofs like rule, erule or
  5275 assumption failed.
  5276 
  5277 * Pure: Locale specifications now produce predicate definitions
  5278 according to the body of text (covering assumptions modulo local
  5279 definitions); predicate "loc_axioms" covers newly introduced text,
  5280 while "loc" is cumulative wrt. all included locale expressions; the
  5281 latter view is presented only on export into the global theory
  5282 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5283 on the old view without predicates;
  5284 
  5285 * Pure: predefined locales "var" and "struct" are useful for sharing
  5286 parameters (as in CASL, for example); just specify something like
  5287 ``var x + var y + struct M'' as import;
  5288 
  5289 * Pure: improved thms_containing: proper indexing of facts instead of
  5290 raw theorems; check validity of results wrt. current name space;
  5291 include local facts of proof configuration (also covers active
  5292 locales), cover fixed variables in index; may use "_" in term
  5293 specification; an optional limit for the number of printed facts may
  5294 be given (the default is 40);
  5295 
  5296 * Pure: disallow duplicate fact bindings within new-style theory files
  5297 (batch-mode only);
  5298 
  5299 * Provers: improved induct method: assumptions introduced by case
  5300 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5301 the goal statement); "foo" still refers to all facts collectively;
  5302 
  5303 * Provers: the function blast.overloaded has been removed: all constants
  5304 are regarded as potentially overloaded, which improves robustness in exchange
  5305 for slight decrease in efficiency;
  5306 
  5307 * Provers/linorder: New generic prover for transitivity reasoning over
  5308 linear orders.  Note: this prover is not efficient!
  5309 
  5310 * Isar: preview of problems to finish 'show' now produce an error
  5311 rather than just a warning (in interactive mode);
  5312 
  5313 
  5314 *** HOL ***
  5315 
  5316 * arith(_tac)
  5317 
  5318  - Produces a counter example if it cannot prove a goal.
  5319    Note that the counter example may be spurious if the goal is not a formula
  5320    of quantifier-free linear arithmetic.
  5321    In ProofGeneral the counter example appears in the trace buffer.
  5322 
  5323  - Knows about div k and mod k where k is a numeral of type nat or int.
  5324 
  5325  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5326    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5327    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5328 
  5329 * simp's arithmetic capabilities have been enhanced a bit: it now
  5330 takes ~= in premises into account (by performing a case split);
  5331 
  5332 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5333 are distributed over a sum of terms;
  5334 
  5335 * New tactic "trans_tac" and method "trans" instantiate
  5336 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5337 "<=", "<" and "=").
  5338 
  5339 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5340 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5341 
  5342 * 'typedef' command has new option "open" to suppress the set
  5343 definition;
  5344 
  5345 * functions Min and Max on finite sets have been introduced (theory
  5346 Finite_Set);
  5347 
  5348 * attribute [symmetric] now works for relations as well; it turns
  5349 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5350 
  5351 * induct over a !!-quantified statement (say !!x1..xn):
  5352   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5353 
  5354 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5355 %x. None. Warning: empty_def now refers to the previously hidden definition
  5356 of the empty set.
  5357 
  5358 * Algebra: formalization of classical algebra.  Intended as base for
  5359 any algebraic development in Isabelle.  Currently covers group theory
  5360 (up to Sylow's theorem) and ring theory (Universal Property of
  5361 Univariate Polynomials).  Contributions welcome;
  5362 
  5363 * GroupTheory: deleted, since its material has been moved to Algebra;
  5364 
  5365 * Complex: new directory of the complex numbers with numeric constants,
  5366 nonstandard complex numbers, and some complex analysis, standard and
  5367 nonstandard (Jacques Fleuriot);
  5368 
  5369 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  5370 
  5371 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  5372 Fleuriot);
  5373 
  5374 * Real/HahnBanach: updated and adapted to locales;
  5375 
  5376 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  5377 Gray and Kramer);
  5378 
  5379 * UNITY: added the Meier-Sanders theory of progress sets;
  5380 
  5381 * MicroJava: bytecode verifier and lightweight bytecode verifier
  5382 as abstract algorithms, instantiated to the JVM;
  5383 
  5384 * Bali: Java source language formalization. Type system, operational
  5385 semantics, axiomatic semantics. Supported language features:
  5386 classes, interfaces, objects,virtual methods, static methods,
  5387 static/instance fields, arrays, access modifiers, definite
  5388 assignment, exceptions.
  5389 
  5390 
  5391 *** ZF ***
  5392 
  5393 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  5394 universe, etc.);
  5395 
  5396 * Main ZF: virtually all theories converted to new-style format;
  5397 
  5398 
  5399 *** ML ***
  5400 
  5401 * Pure: Tactic.prove provides sane interface for internal proofs;
  5402 omits the infamous "standard" operation, so this is more appropriate
  5403 than prove_goalw_cterm in many situations (e.g. in simprocs);
  5404 
  5405 * Pure: improved error reporting of simprocs;
  5406 
  5407 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  5408 up simprocs;
  5409 
  5410 
  5411 *** Document preparation ***
  5412 
  5413 * uses \par instead of \\ for line breaks in theory text. This may
  5414 shift some page breaks in large documents. To get the old behaviour
  5415 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  5416 
  5417 * minimized dependencies of isabelle.sty and isabellesym.sty on
  5418 other packages
  5419 
  5420 * \<euro> now needs package babel/greek instead of marvosym (which
  5421 broke \Rightarrow)
  5422 
  5423 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  5424 textcomp package)
  5425 
  5426 
  5427 
  5428 New in Isabelle2002 (March 2002)
  5429 --------------------------------
  5430 
  5431 *** Document preparation ***
  5432 
  5433 * greatly simplified document preparation setup, including more
  5434 graceful interpretation of isatool usedir -i/-d/-D options, and more
  5435 instructive isatool mkdir; users should basically be able to get
  5436 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  5437 users may run a separate document processing stage manually like this:
  5438 "isatool usedir -D output HOL Test && isatool document Test/output";
  5439 
  5440 * theory dependency graph may now be incorporated into documents;
  5441 isatool usedir -g true will produce session_graph.eps/.pdf for use
  5442 with \includegraphics of LaTeX;
  5443 
  5444 * proper spacing of consecutive markup elements, especially text
  5445 blocks after section headings;
  5446 
  5447 * support bold style (for single symbols only), input syntax is like
  5448 this: "\<^bold>\<alpha>" or "\<^bold>A";
  5449 
  5450 * \<bullet> is now output as bold \cdot by default, which looks much
  5451 better in printed text;
  5452 
  5453 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  5454 note that these symbols are currently unavailable in Proof General /
  5455 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  5456 
  5457 * isatool latex no longer depends on changed TEXINPUTS, instead
  5458 isatool document copies the Isabelle style files to the target
  5459 location;
  5460 
  5461 
  5462 *** Isar ***
  5463 
  5464 * Pure/Provers: improved proof by cases and induction;
  5465   - 'case' command admits impromptu naming of parameters (such as
  5466     "case (Suc n)");
  5467   - 'induct' method divinates rule instantiation from the inductive
  5468     claim; no longer requires excessive ?P bindings for proper
  5469     instantiation of cases;
  5470   - 'induct' method properly enumerates all possibilities of set/type
  5471     rules; as a consequence facts may be also passed through *type*
  5472     rules without further ado;
  5473   - 'induct' method now derives symbolic cases from the *rulified*
  5474     rule (before it used to rulify cases stemming from the internal
  5475     atomized version); this means that the context of a non-atomic
  5476     statement becomes is included in the hypothesis, avoiding the
  5477     slightly cumbersome show "PROP ?case" form;
  5478   - 'induct' may now use elim-style induction rules without chaining
  5479     facts, using ``missing'' premises from the goal state; this allows
  5480     rules stemming from inductive sets to be applied in unstructured
  5481     scripts, while still benefitting from proper handling of non-atomic
  5482     statements; NB: major inductive premises need to be put first, all
  5483     the rest of the goal is passed through the induction;
  5484   - 'induct' proper support for mutual induction involving non-atomic
  5485     rule statements (uses the new concept of simultaneous goals, see
  5486     below);
  5487   - append all possible rule selections, but only use the first
  5488     success (no backtracking);
  5489   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  5490   - undeclared rule case names default to numbers 1, 2, 3, ...;
  5491   - added 'print_induct_rules' (covered by help item in recent Proof
  5492     General versions);
  5493   - moved induct/cases attributes to Pure, methods to Provers;
  5494   - generic method setup instantiated for FOL and HOL;
  5495 
  5496 * Pure: support multiple simultaneous goal statements, for example
  5497 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  5498 meta-level mechanism, this acts as if several individual goals had
  5499 been stated separately; in particular common proof methods need to be
  5500 repeated in order to cover all claims; note that a single elimination
  5501 step is *not* sufficient to establish the two conjunctions, so this
  5502 fails:
  5503 
  5504   assume "A & B" then have A and B ..   (*".." fails*)
  5505 
  5506 better use "obtain" in situations as above; alternative refer to
  5507 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  5508 
  5509 * Pure: proper integration with ``locales''; unlike the original
  5510 version by Florian Kammller, Isar locales package high-level proof
  5511 contexts rather than raw logical ones (e.g. we admit to include
  5512 attributes everywhere); operations on locales include merge and
  5513 rename; support for implicit arguments (``structures''); simultaneous
  5514 type-inference over imports and text; see also HOL/ex/Locales.thy for
  5515 some examples;
  5516 
  5517 * Pure: the following commands have been ``localized'', supporting a
  5518 target locale specification "(in name)": 'lemma', 'theorem',
  5519 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  5520 stored both within the locale and at the theory level (exported and
  5521 qualified by the locale name);
  5522 
  5523 * Pure: theory goals may now be specified in ``long'' form, with
  5524 ad-hoc contexts consisting of arbitrary locale elements. for example
  5525 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  5526 definitions may be given, too); the result is a meta-level rule with
  5527 the context elements being discharged in the obvious way;
  5528 
  5529 * Pure: new proof command 'using' allows to augment currently used
  5530 facts after a goal statement ('using' is syntactically analogous to
  5531 'apply', but acts on the goal's facts only); this allows chained facts
  5532 to be separated into parts given before and after a claim, as in
  5533 ``from a and b have C using d and e <proof>'';
  5534 
  5535 * Pure: renamed "antecedent" case to "rule_context";
  5536 
  5537 * Pure: new 'judgment' command records explicit information about the
  5538 object-logic embedding (used by several tools internally); no longer
  5539 use hard-wired "Trueprop";
  5540 
  5541 * Pure: added 'corollary' command;
  5542 
  5543 * Pure: fixed 'token_translation' command;
  5544 
  5545 * Pure: removed obsolete 'exported' attribute;
  5546 
  5547 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  5548 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  5549 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  5550 
  5551 * Pure: method 'atomize' presents local goal premises as object-level
  5552 statements (atomic meta-level propositions); setup controlled via
  5553 rewrite rules declarations of 'atomize' attribute; example
  5554 application: 'induct' method with proper rule statements in improper
  5555 proof *scripts*;
  5556 
  5557 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  5558 now consider the syntactic context of assumptions, giving a better
  5559 chance to get type-inference of the arguments right (this is
  5560 especially important for locales);
  5561 
  5562 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  5563 mode;
  5564 
  5565 * Pure/obtain: the formal conclusion "thesis", being marked as
  5566 ``internal'', may no longer be reference directly in the text;
  5567 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  5568 situations;
  5569 
  5570 * Pure: generic 'sym' attribute which declares a rule both as pure
  5571 'elim?' and for the 'symmetric' operation;
  5572 
  5573 * Pure: marginal comments ``--'' may now occur just anywhere in the
  5574 text; the fixed correlation with particular command syntax has been
  5575 discontinued;
  5576 
  5577 * Pure: new method 'rules' is particularly well-suited for proof
  5578 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  5579 but often produces more compact proof terms with less detours;
  5580 
  5581 * Pure/Provers/classical: simplified integration with pure rule
  5582 attributes and methods; the classical "intro?/elim?/dest?"
  5583 declarations coincide with the pure ones; the "rule" method no longer
  5584 includes classically swapped intros; "intro" and "elim" methods no
  5585 longer pick rules from the context; also got rid of ML declarations
  5586 AddXIs/AddXEs/AddXDs; all of this has some potential for
  5587 INCOMPATIBILITY;
  5588 
  5589 * Provers/classical: attribute 'swapped' produces classical inversions
  5590 of introduction rules;
  5591 
  5592 * Provers/simplifier: 'simplified' attribute may refer to explicit
  5593 rules instead of full simplifier context; 'iff' attribute handles
  5594 conditional rules;
  5595 
  5596 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  5597 
  5598 * HOL: 'recdef' now fails on unfinished automated proofs, use
  5599 "(permissive)" option to recover old behavior;
  5600 
  5601 * HOL: 'inductive' no longer features separate (collective) attributes
  5602 for 'intros' (was found too confusing);
  5603 
  5604 * HOL: properly declared induction rules less_induct and
  5605 wf_induct_rule;
  5606 
  5607 
  5608 *** HOL ***
  5609 
  5610 * HOL: moved over to sane numeral syntax; the new policy is as
  5611 follows:
  5612 
  5613   - 0 and 1 are polymorphic constants, which are defined on any
  5614   numeric type (nat, int, real etc.);
  5615 
  5616   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  5617   binary representation internally;
  5618 
  5619   - type nat has special constructor Suc, and generally prefers Suc 0
  5620   over 1::nat and Suc (Suc 0) over 2::nat;
  5621 
  5622 This change may cause significant problems of INCOMPATIBILITY; here
  5623 are some hints on converting existing sources:
  5624 
  5625   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  5626   entities, so expressions involving "-" (unary or binary minus) need
  5627   to be spaced properly;
  5628 
  5629   - existing occurrences of "1" may need to be constraint "1::nat" or
  5630   even replaced by Suc 0; similar for old "2";
  5631 
  5632   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  5633 
  5634   - remove all special provisions on numerals in proofs;
  5635 
  5636 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  5637 representation (depends on bin_arith_simps in the default context);
  5638 
  5639 * HOL: symbolic syntax for x^2 (numeral 2);
  5640 
  5641 * HOL: the class of all HOL types is now called "type" rather than
  5642 "term"; INCOMPATIBILITY, need to adapt references to this type class
  5643 in axclass/classes, instance/arities, and (usually rare) occurrences
  5644 in typings (of consts etc.); internally the class is called
  5645 "HOL.type", ML programs should refer to HOLogic.typeS;
  5646 
  5647 * HOL/record package improvements:
  5648   - new derived operations "fields" to build a partial record section,
  5649     "extend" to promote a fixed record to a record scheme, and
  5650     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  5651     declared as simp by default;
  5652   - shared operations ("more", "fields", etc.) now need to be always
  5653     qualified) --- potential INCOMPATIBILITY;
  5654   - removed "make_scheme" operations (use "make" with "extend") --
  5655     INCOMPATIBILITY;
  5656   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  5657   - provides cases/induct rules for use with corresponding Isar
  5658     methods (for concrete records, record schemes, concrete more
  5659     parts, and schematic more parts -- in that order);
  5660   - internal definitions directly based on a light-weight abstract
  5661     theory of product types over typedef rather than datatype;
  5662 
  5663 * HOL: generic code generator for generating executable ML code from
  5664 specifications; specific support for HOL constructs such as inductive
  5665 datatypes and sets, as well as recursive functions; can be invoked
  5666 via 'generate_code' theory section;
  5667 
  5668 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  5669 
  5670 * HOL: consolidated and renamed several theories.  In particular:
  5671         Ord.thy has been absorbed into HOL.thy
  5672         String.thy has been absorbed into List.thy
  5673 
  5674 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  5675 (beware of argument permutation!);
  5676 
  5677 * HOL: linorder_less_split superseded by linorder_cases;
  5678 
  5679 * HOL/List: "nodups" renamed to "distinct";
  5680 
  5681 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  5682 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  5683   - Ex_def has changed, now need to use some_eq_ex
  5684 
  5685 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  5686 in this (rare) case use:
  5687 
  5688   delSWrapper "split_all_tac"
  5689   addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
  5690 
  5691 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
  5692 MAY FAIL;
  5693 
  5694 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
  5695 Isabelle's type classes, ^ on functions and relations has too general
  5696 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be
  5697 necessary to attach explicit type constraints;
  5698 
  5699 * HOL/Relation: the prefix name of the infix "O" has been changed from
  5700 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been
  5701 renamed accordingly (eg "compI" -> "rel_compI").
  5702 
  5703 * HOL: syntax translations now work properly with numerals and records
  5704 expressions;
  5705 
  5706 * HOL: bounded abstraction now uses syntax "%" / "\<lambda>" instead
  5707 of "lam" -- INCOMPATIBILITY;
  5708 
  5709 * HOL: got rid of some global declarations (potential INCOMPATIBILITY
  5710 for ML tools): const "()" renamed "Product_Type.Unity", type "unit"
  5711 renamed "Product_Type.unit";
  5712 
  5713 * HOL: renamed rtrancl_into_rtrancl2 to converse_rtrancl_into_rtrancl
  5714 
  5715 * HOL: removed obsolete theorem "optionE" (use "option.exhaust", or
  5716 the "cases" method);
  5717 
  5718 * HOL/GroupTheory: group theory examples including Sylow's theorem (by
  5719 Florian Kammller);
  5720 
  5721 * HOL/IMP: updated and converted to new-style theory format; several
  5722 parts turned into readable document, with proper Isar proof texts and
  5723 some explanations (by Gerwin Klein);
  5724 
  5725 * HOL-Real: added Complex_Numbers (by Gertrud Bauer);
  5726 
  5727 * HOL-Hyperreal is now a logic image;
  5728 
  5729 
  5730 *** HOLCF ***
  5731 
  5732 * Isar: consts/constdefs supports mixfix syntax for continuous
  5733 operations;
  5734 
  5735 * Isar: domain package adapted to new-style theory format, e.g. see
  5736 HOLCF/ex/Dnat.thy;
  5737 
  5738 * theory Lift: proper use of rep_datatype lift instead of ML hacks --
  5739 potential INCOMPATIBILITY; now use plain induct_tac instead of former
  5740 lift.induct_tac, always use UU instead of Undef;
  5741 
  5742 * HOLCF/IMP: updated and converted to new-style theory;
  5743 
  5744 
  5745 *** ZF ***
  5746 
  5747 * Isar: proper integration of logic-specific tools and packages,
  5748 including theory commands '(co)inductive', '(co)datatype',
  5749 'rep_datatype', 'inductive_cases', as well as methods 'ind_cases',
  5750 'induct_tac', 'case_tac', and 'typecheck' (with attribute 'TC');
  5751 
  5752 * theory Main no longer includes AC; for the Axiom of Choice, base
  5753 your theory on Main_ZFC;
  5754 
  5755 * the integer library now covers quotients and remainders, with many
  5756 laws relating division to addition, multiplication, etc.;
  5757 
  5758 * ZF/UNITY: Chandy and Misra's UNITY is now available in ZF, giving a
  5759 typeless version of the formalism;
  5760 
  5761 * ZF/AC, Coind, IMP, Resid: updated and converted to new-style theory
  5762 format;
  5763 
  5764 * ZF/Induct: new directory for examples of inductive definitions,
  5765 including theory Multiset for multiset orderings; converted to
  5766 new-style theory format;
  5767 
  5768 * ZF: many new theorems about lists, ordinals, etc.;
  5769 
  5770 
  5771 *** General ***
  5772 
  5773 * Pure/kernel: meta-level proof terms (by Stefan Berghofer); reference
  5774 variable proof controls level of detail: 0 = no proofs (only oracle
  5775 dependencies), 1 = lemma dependencies, 2 = compact proof terms; see
  5776 also ref manual for further ML interfaces;
  5777 
  5778 * Pure/axclass: removed obsolete ML interface
  5779 goal_subclass/goal_arity;
  5780 
  5781 * Pure/syntax: new token syntax "num" for plain numerals (without "#"
  5782 of "xnum"); potential INCOMPATIBILITY, since -0, -1 etc. are now
  5783 separate tokens, so expressions involving minus need to be spaced
  5784 properly;
  5785 
  5786 * Pure/syntax: support non-oriented infixes, using keyword "infix"
  5787 rather than "infixl" or "infixr";
  5788 
  5789 * Pure/syntax: concrete syntax for dummy type variables admits genuine
  5790 sort constraint specifications in type inference; e.g. "x::_::foo"
  5791 ensures that the type of "x" is of sort "foo" (but not necessarily a
  5792 type variable);
  5793 
  5794 * Pure/syntax: print modes "type_brackets" and "no_type_brackets"
  5795 control output of nested => (types); the default behavior is
  5796 "type_brackets";
  5797 
  5798 * Pure/syntax: builtin parse translation for "_constify" turns valued
  5799 tokens into AST constants;
  5800 
  5801 * Pure/syntax: prefer later declarations of translations and print
  5802 translation functions; potential INCOMPATIBILITY: need to reverse
  5803 multiple declarations for same syntax element constant;
  5804 
  5805 * Pure/show_hyps reset by default (in accordance to existing Isar
  5806 practice);
  5807 
  5808 * Provers/classical: renamed addaltern to addafter, addSaltern to
  5809 addSafter;
  5810 
  5811 * Provers/clasimp: ``iff'' declarations now handle conditional rules
  5812 as well;
  5813 
  5814 * system: tested support for MacOS X; should be able to get Isabelle +
  5815 Proof General to work in a plain Terminal after installing Poly/ML
  5816 (e.g. from the Isabelle distribution area) and GNU bash alone
  5817 (e.g. from http://www.apple.com); full X11, XEmacs and X-Symbol
  5818 support requires further installations, e.g. from
  5819 http://fink.sourceforge.net/);
  5820 
  5821 * system: support Poly/ML 4.1.1 (able to manage larger heaps);
  5822 
  5823 * system: reduced base memory usage by Poly/ML (approx. 20 MB instead
  5824 of 40 MB), cf. ML_OPTIONS;
  5825 
  5826 * system: Proof General keywords specification is now part of the
  5827 Isabelle distribution (see etc/isar-keywords.el);
  5828 
  5829 * system: support for persistent Proof General sessions (refrain from
  5830 outdating all loaded theories on startup); user may create writable
  5831 logic images like this: ``isabelle -q HOL Test'';
  5832 
  5833 * system: smart selection of Isabelle process versus Isabelle
  5834 interface, accommodates case-insensitive file systems (e.g. HFS+); may
  5835 run both "isabelle" and "Isabelle" even if file names are badly
  5836 damaged (executable inspects the case of the first letter of its own
  5837 name); added separate "isabelle-process" and "isabelle-interface";
  5838 
  5839 * system: refrain from any attempt at filtering input streams; no
  5840 longer support ``8bit'' encoding of old isabelle font, instead proper
  5841 iso-latin characters may now be used; the related isatools
  5842 "symbolinput" and "nonascii" have disappeared as well;
  5843 
  5844 * system: removed old "xterm" interface (the print modes "xterm" and
  5845 "xterm_color" are still available for direct use in a suitable
  5846 terminal);
  5847 
  5848 
  5849 
  5850 New in Isabelle99-2 (February 2001)
  5851 -----------------------------------
  5852 
  5853 *** Overview of INCOMPATIBILITIES ***
  5854 
  5855 * HOL: please note that theories in the Library and elsewhere often use the
  5856 new-style (Isar) format; to refer to their theorems in an ML script you must
  5857 bind them to ML identifers by e.g.      val thm_name = thm "thm_name";
  5858 
  5859 * HOL: inductive package no longer splits induction rule aggressively,
  5860 but only as far as specified by the introductions given; the old
  5861 format may be recovered via ML function complete_split_rule or attribute
  5862 'split_rule (complete)';
  5863 
  5864 * HOL: induct renamed to lfp_induct, lfp_Tarski to lfp_unfold,
  5865 gfp_Tarski to gfp_unfold;
  5866 
  5867 * HOL: contrapos, contrapos2 renamed to contrapos_nn, contrapos_pp;
  5868 
  5869 * HOL: infix "dvd" now has priority 50 rather than 70 (because it is a
  5870 relation); infix "^^" has been renamed "``"; infix "``" has been
  5871 renamed "`"; "univalent" has been renamed "single_valued";
  5872 
  5873 * HOL/Real: "rinv" and "hrinv" replaced by overloaded "inverse"
  5874 operation;
  5875 
  5876 * HOLCF: infix "`" has been renamed "$"; the symbol syntax is \<cdot>;
  5877 
  5878 * Isar: 'obtain' no longer declares "that" fact as simp/intro;
  5879 
  5880 * Isar/HOL: method 'induct' now handles non-atomic goals; as a
  5881 consequence, it is no longer monotonic wrt. the local goal context
  5882 (which is now passed through the inductive cases);
  5883 
  5884 * Document preparation: renamed standard symbols \<ll> to \<lless> and
  5885 \<gg> to \<ggreater>;
  5886 
  5887 
  5888 *** Document preparation ***
  5889 
  5890 * \isabellestyle{NAME} selects version of Isabelle output (currently
  5891 available: are "it" for near math-mode best-style output, "sl" for
  5892 slanted text style, and "tt" for plain type-writer; if no
  5893 \isabellestyle command is given, output is according to slanted
  5894 type-writer);
  5895 
  5896 * support sub/super scripts (for single symbols only), input syntax is
  5897 like this: "A\<^sup>*" or "A\<^sup>\<star>";
  5898 
  5899 * some more standard symbols; see Appendix A of the system manual for
  5900 the complete list of symbols defined in isabellesym.sty;
  5901 
  5902 * improved isabelle style files; more abstract symbol implementation
  5903 (should now use \isamath{...} and \isatext{...} in custom symbol
  5904 definitions);
  5905 
  5906 * antiquotation @{goals} and @{subgoals} for output of *dynamic* goals
  5907 state; Note that presentation of goal states does not conform to
  5908 actual human-readable proof documents.  Please do not include goal
  5909 states into document output unless you really know what you are doing!
  5910 
  5911 * proper indentation of antiquoted output with proportional LaTeX
  5912 fonts;
  5913 
  5914 * no_document ML operator temporarily disables LaTeX document
  5915 generation;
  5916 
  5917 * isatool unsymbolize tunes sources for plain ASCII communication;
  5918 
  5919 
  5920 *** Isar ***
  5921 
  5922 * Pure: Isar now suffers initial goal statements to contain unbound
  5923 schematic variables (this does not conform to actual readable proof
  5924 documents, due to unpredictable outcome and non-compositional proof
  5925 checking); users who know what they are doing may use schematic goals
  5926 for Prolog-style synthesis of proven results;
  5927 
  5928 * Pure: assumption method (an implicit finishing) now handles actual
  5929 rules as well;
  5930 
  5931 * Pure: improved 'obtain' --- moved to Pure, insert "that" into
  5932 initial goal, declare "that" only as Pure intro (only for single
  5933 steps); the "that" rule assumption may now be involved in implicit
  5934 finishing, thus ".." becomes a feasible for trivial obtains;
  5935 
  5936 * Pure: default proof step now includes 'intro_classes'; thus trivial
  5937 instance proofs may be performed by "..";
  5938 
  5939 * Pure: ?thesis / ?this / "..." now work for pure meta-level
  5940 statements as well;
  5941 
  5942 * Pure: more robust selection of calculational rules;
  5943 
  5944 * Pure: the builtin notion of 'finished' goal now includes the ==-refl
  5945 rule (as well as the assumption rule);
  5946 
  5947 * Pure: 'thm_deps' command visualizes dependencies of theorems and
  5948 lemmas, using the graph browser tool;
  5949 
  5950 * Pure: predict failure of "show" in interactive mode;
  5951 
  5952 * Pure: 'thms_containing' now takes actual terms as arguments;
  5953 
  5954 * HOL: improved method 'induct' --- now handles non-atomic goals
  5955 (potential INCOMPATIBILITY); tuned error handling;
  5956 
  5957 * HOL: cases and induct rules now provide explicit hints about the
  5958 number of facts to be consumed (0 for "type" and 1 for "set" rules);
  5959 any remaining facts are inserted into the goal verbatim;
  5960 
  5961 * HOL: local contexts (aka cases) may now contain term bindings as
  5962 well; the 'cases' and 'induct' methods new provide a ?case binding for
  5963 the result to be shown in each case;
  5964 
  5965 * HOL: added 'recdef_tc' command;
  5966 
  5967 * isatool convert assists in eliminating legacy ML scripts;
  5968 
  5969 
  5970 *** HOL ***
  5971 
  5972 * HOL/Library: a collection of generic theories to be used together
  5973 with main HOL; the theory loader path already includes this directory
  5974 by default; the following existing theories have been moved here:
  5975 HOL/Induct/Multiset, HOL/Induct/Acc (as Accessible_Part), HOL/While
  5976 (as While_Combinator), HOL/Lex/Prefix (as List_Prefix);
  5977 
  5978 * HOL/Unix: "Some aspects of Unix file-system security", a typical
  5979 modelling and verification task performed in Isabelle/HOL +
  5980 Isabelle/Isar + Isabelle document preparation (by Markus Wenzel).
  5981 
  5982 * HOL/Algebra: special summation operator SUM no longer exists, it has
  5983 been replaced by setsum; infix 'assoc' now has priority 50 (like
  5984 'dvd'); axiom 'one_not_zero' has been moved from axclass 'ring' to
  5985 'domain', this makes the theory consistent with mathematical
  5986 literature;
  5987 
  5988 * HOL basics: added overloaded operations "inverse" and "divide"
  5989 (infix "/"), syntax for generic "abs" operation, generic summation
  5990 operator \<Sum>;
  5991 
  5992 * HOL/typedef: simplified package, provide more useful rules (see also
  5993 HOL/subset.thy);
  5994 
  5995 * HOL/datatype: induction rule for arbitrarily branching datatypes is
  5996 now expressed as a proper nested rule (old-style tactic scripts may
  5997 require atomize_strip_tac to cope with non-atomic premises);
  5998 
  5999 * HOL: renamed theory "Prod" to "Product_Type", renamed "split" rule
  6000 to "split_conv" (old name still available for compatibility);
  6001 
  6002 * HOL: improved concrete syntax for strings (e.g. allows translation
  6003 rules with string literals);
  6004 
  6005 * HOL-Real-Hyperreal: this extends HOL-Real with the hyperreals
  6006  and Fleuriot's mechanization of analysis, including the transcendental
  6007  functions for the reals;
  6008 
  6009 * HOL/Real, HOL/Hyperreal: improved arithmetic simplification;
  6010 
  6011 
  6012 *** CTT ***
  6013 
  6014 * CTT: x-symbol support for Pi, Sigma, -->, : (membership); note that
  6015 "lam" is displayed as TWO lambda-symbols
  6016 
  6017 * CTT: theory Main now available, containing everything (that is, Bool
  6018 and Arith);
  6019 
  6020 
  6021 *** General ***
  6022 
  6023 * Pure: the Simplifier has been implemented properly as a derived rule
  6024 outside of the actual kernel (at last!); the overall performance
  6025 penalty in practical applications is about 50%, while reliability of
  6026 the Isabelle inference kernel has been greatly improved;
  6027 
  6028 * print modes "brackets" and "no_brackets" control output of nested =>
  6029 (types) and ==> (props); the default behaviour is "brackets";
  6030 
  6031 * Provers: fast_tac (and friends) now handle actual object-logic rules
  6032 as assumptions as well;
  6033 
  6034 * system: support Poly/ML 4.0;
  6035 
  6036 * system: isatool install handles KDE version 1 or 2;
  6037 
  6038 
  6039 
  6040 New in Isabelle99-1 (October 2000)
  6041 ----------------------------------
  6042 
  6043 *** Overview of INCOMPATIBILITIES ***
  6044 
  6045 * HOL: simplification of natural numbers is much changed; to partly
  6046 recover the old behaviour (e.g. to prevent n+n rewriting to #2*n)
  6047 issue the following ML commands:
  6048 
  6049   Delsimprocs Nat_Numeral_Simprocs.cancel_numerals;
  6050   Delsimprocs [Nat_Numeral_Simprocs.combine_numerals];
  6051 
  6052 * HOL: simplification no longer dives into case-expressions; this is
  6053 controlled by "t.weak_case_cong" for each datatype t;
  6054 
  6055 * HOL: nat_less_induct renamed to less_induct;
  6056 
  6057 * HOL: systematic renaming of the SOME (Eps) rules, may use isatool
  6058 fixsome to patch .thy and .ML sources automatically;
  6059 
  6060   select_equality  -> some_equality
  6061   select_eq_Ex     -> some_eq_ex
  6062   selectI2EX       -> someI2_ex
  6063   selectI2         -> someI2
  6064   selectI          -> someI
  6065   select1_equality -> some1_equality
  6066   Eps_sym_eq       -> some_sym_eq_trivial
  6067   Eps_eq           -> some_eq_trivial
  6068 
  6069 * HOL: exhaust_tac on datatypes superceded by new generic case_tac;
  6070 
  6071 * HOL: removed obsolete theorem binding expand_if (refer to split_if
  6072 instead);
  6073 
  6074 * HOL: the recursion equations generated by 'recdef' are now called
  6075 f.simps instead of f.rules;
  6076 
  6077 * HOL: qed_spec_mp now also handles bounded ALL as well;
  6078 
  6079 * HOL: 0 is now overloaded, so the type constraint ":: nat" may
  6080 sometimes be needed;
  6081 
  6082 * HOL: the constant for "f``x" is now "image" rather than "op ``";
  6083 
  6084 * HOL: the constant for "f-``x" is now "vimage" rather than "op -``";
  6085 
  6086 * HOL: the disjoint sum is now "<+>" instead of "Plus"; the cartesian
  6087 product is now "<*>" instead of "Times"; the lexicographic product is
  6088 now "<*lex*>" instead of "**";
  6089 
  6090 * HOL: theory Sexp is now in HOL/Induct examples (it used to be part
  6091 of main HOL, but was unused); better use HOL's datatype package;
  6092 
  6093 * HOL: removed "symbols" syntax for constant "override" of theory Map;
  6094 the old syntax may be recovered as follows:
  6095 
  6096   syntax (symbols)
  6097     override  :: "('a ~=> 'b) => ('a ~=> 'b) => ('a ~=> 'b)"
  6098       (infixl "\\<oplus>" 100)
  6099 
  6100 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  6101 
  6102 * HOL/ML: even fewer consts are declared as global (see theories Ord,
  6103 Lfp, Gfp, WF); this only affects ML packages that refer to const names
  6104 internally;
  6105 
  6106 * HOL and ZF: syntax for quotienting wrt an equivalence relation
  6107 changed from A/r to A//r;
  6108 
  6109 * ZF: new treatment of arithmetic (nat & int) may break some old
  6110 proofs;
  6111 
  6112 * Isar: renamed some attributes (RS -> THEN, simplify -> simplified,
  6113 rulify -> rule_format, elimify -> elim_format, ...);
  6114 
  6115 * Isar/Provers: intro/elim/dest attributes changed; renamed
  6116 intro/intro!/intro!! flags to intro!/intro/intro? (in most cases, one
  6117 should have to change intro!! to intro? only); replaced "delrule" by
  6118 "rule del";
  6119 
  6120 * Isar/HOL: renamed "intrs" to "intros" in inductive definitions;
  6121 
  6122 * Provers: strengthened force_tac by using new first_best_tac;
  6123 
  6124 * LaTeX document preparation: several changes of isabelle.sty (see
  6125 lib/texinputs);
  6126 
  6127 
  6128 *** Document preparation ***
  6129 
  6130 * formal comments (text blocks etc.) in new-style theories may now
  6131 contain antiquotations of thm/prop/term/typ/text to be presented
  6132 according to latex print mode; concrete syntax is like this:
  6133 @{term[show_types] "f(x) = a + x"};
  6134 
  6135 * isatool mkdir provides easy setup of Isabelle session directories,
  6136 including proper document sources;
  6137 
  6138 * generated LaTeX sources are now deleted after successful run
  6139 (isatool document -c); may retain a copy somewhere else via -D option
  6140 of isatool usedir;
  6141 
  6142 * isatool usedir -D now lets isatool latex -o sty update the Isabelle
  6143 style files, achieving self-contained LaTeX sources and simplifying
  6144 LaTeX debugging;
  6145 
  6146 * old-style theories now produce (crude) LaTeX output as well;
  6147 
  6148 * browser info session directories are now self-contained (may be put
  6149 on WWW server seperately); improved graphs of nested sessions; removed
  6150 graph for 'all sessions';
  6151 
  6152 * several improvements in isabelle style files; \isabellestyle{it}
  6153 produces fake math mode output; \isamarkupheader is now \section by
  6154 default; see lib/texinputs/isabelle.sty etc.;
  6155 
  6156 
  6157 *** Isar ***
  6158 
  6159 * Isar/Pure: local results and corresponding term bindings are now
  6160 subject to Hindley-Milner polymorphism (similar to ML); this
  6161 accommodates incremental type-inference very nicely;
  6162 
  6163 * Isar/Pure: new derived language element 'obtain' supports
  6164 generalized existence reasoning;
  6165 
  6166 * Isar/Pure: new calculational elements 'moreover' and 'ultimately'
  6167 support accumulation of results, without applying any rules yet;
  6168 useful to collect intermediate results without explicit name
  6169 references, and for use with transitivity rules with more than 2
  6170 premises;
  6171 
  6172 * Isar/Pure: scalable support for case-analysis type proofs: new
  6173 'case' language element refers to local contexts symbolically, as
  6174 produced by certain proof methods; internally, case names are attached
  6175 to theorems as "tags";
  6176 
  6177 * Isar/Pure: theory command 'hide' removes declarations from
  6178 class/type/const name spaces;
  6179 
  6180 * Isar/Pure: theory command 'defs' supports option "(overloaded)" to
  6181 indicate potential overloading;
  6182 
  6183 * Isar/Pure: changed syntax of local blocks from {{ }} to { };
  6184 
  6185 * Isar/Pure: syntax of sorts made 'inner', i.e. have to write
  6186 "{a,b,c}" instead of {a,b,c};
  6187 
  6188 * Isar/Pure now provides its own version of intro/elim/dest
  6189 attributes; useful for building new logics, but beware of confusion
  6190 with the version in Provers/classical;
  6191 
  6192 * Isar/Pure: the local context of (non-atomic) goals is provided via
  6193 case name 'antecedent';
  6194 
  6195 * Isar/Pure: removed obsolete 'transfer' attribute (transfer of thms
  6196 to the current context is now done automatically);
  6197 
  6198 * Isar/Pure: theory command 'method_setup' provides a simple interface
  6199 for definining proof methods in ML;
  6200 
  6201 * Isar/Provers: intro/elim/dest attributes changed; renamed
  6202 intro/intro!/intro!! flags to intro!/intro/intro? (INCOMPATIBILITY, in
  6203 most cases, one should have to change intro!! to intro? only);
  6204 replaced "delrule" by "rule del";
  6205 
  6206 * Isar/Provers: new 'hypsubst' method, plain 'subst' method and
  6207 'symmetric' attribute (the latter supercedes [RS sym]);
  6208 
  6209 * Isar/Provers: splitter support (via 'split' attribute and 'simp'
  6210 method modifier); 'simp' method: 'only:' modifier removes loopers as
  6211 well (including splits);
  6212 
  6213 * Isar/Provers: Simplifier and Classical methods now support all kind
  6214 of modifiers used in the past, including 'cong', 'iff', etc.
  6215 
  6216 * Isar/Provers: added 'fastsimp' and 'clarsimp' methods (combination
  6217 of Simplifier and Classical reasoner);
  6218 
  6219 * Isar/HOL: new proof method 'cases' and improved version of 'induct'
  6220 now support named cases; major packages (inductive, datatype, primrec,
  6221 recdef) support case names and properly name parameters;
  6222 
  6223 * Isar/HOL: new transitivity rules for substitution in inequalities --
  6224 monotonicity conditions are extracted to be proven at end of
  6225 calculations;
  6226 
  6227 * Isar/HOL: removed 'case_split' thm binding, should use 'cases' proof
  6228 method anyway;
  6229 
  6230 * Isar/HOL: removed old expand_if = split_if; theorems if_splits =
  6231 split_if split_if_asm; datatype package provides theorems foo.splits =
  6232 foo.split foo.split_asm for each datatype;
  6233 
  6234 * Isar/HOL: tuned inductive package, rename "intrs" to "intros"
  6235 (potential INCOMPATIBILITY), emulation of mk_cases feature for proof
  6236 scripts: new 'inductive_cases' command and 'ind_cases' method; (Note:
  6237 use "(cases (simplified))" method in proper proof texts);
  6238