NEWS
author bulwahn
Thu Sep 09 14:38:14 2010 +0200 (2010-09-09)
changeset 39250 548a3e5521ab
parent 39215 7b2631c91a95
child 39277 f263522ab226
permissions -rw-r--r--
changing String.literal to a type instead of a datatype
     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 
    72 *** HOL ***
    73 
    74 * String.literal is a type, but not a datatype. INCOMPATIBILITY.
    75  
    76 * Renamed lemmas: expand_fun_eq -> ext_iff, expand_set_eq -> set_ext_iff
    77 
    78 * Renamed class eq and constant eq (for code generation) to class equal
    79 and constant equal, plus renaming of related facts and various tuning.
    80 INCOMPATIBILITY.
    81 
    82 * Scala (2.8 or higher) has been added to the target languages of
    83 the code generator.
    84 
    85 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
    86 
    87 * Theory SetsAndFunctions has been split into Function_Algebras and Set_Algebras;
    88 canonical names for instance definitions for functions; various improvements.
    89 INCOMPATIBILITY.
    90 
    91 * Records: logical foundation type for records do not carry a '_type' suffix
    92 any longer.  INCOMPATIBILITY.
    93 
    94 * Code generation for records: more idiomatic representation of record types.
    95 Warning: records are not covered by ancient SML code generation any longer.
    96 INCOMPATIBILITY.  In cases of need, a suitable rep_datatype declaration
    97 helps to succeed then:
    98 
    99   record 'a foo = ...
   100   ...
   101   rep_datatype foo_ext ...
   102 
   103 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   104 INCOMPATIBILITY.
   105 
   106 * Quickcheck in locales considers interpretations of that locale for
   107 counter example search.
   108 
   109 * Theory Library/Monad_Syntax provides do-syntax for monad types.  Syntax
   110 in Library/State_Monad has been changed to avoid ambiguities.
   111 INCOMPATIBILITY.
   112 
   113 * Code generator: export_code without explicit file declaration prints
   114 to standard output.  INCOMPATIBILITY.
   115 
   116 * Abolished symbol type names:  "prod" and "sum" replace "*" and "+"
   117 respectively.  INCOMPATIBILITY.
   118 
   119 * Constant "split" has been merged with constant "prod_case";  names
   120 of ML functions, facts etc. involving split have been retained so far,
   121 though.  INCOMPATIBILITY.
   122 
   123 * Dropped old infix syntax "mem" for List.member;  use "in set"
   124 instead.  INCOMPATIBILITY.
   125 
   126 * Refactoring of code-generation specific operations in List.thy
   127 
   128   constants
   129     null ~> List.null
   130 
   131   facts
   132     mem_iff ~> member_def
   133     null_empty ~> null_def
   134 
   135 INCOMPATIBILITY.  Note that these were not suppossed to be used
   136 regularly unless for striking reasons;  their main purpose was code
   137 generation.
   138 
   139 * Some previously unqualified names have been qualified:
   140 
   141   types
   142     bool ~> HOL.bool
   143     nat ~> Nat.nat
   144 
   145   constants
   146     Trueprop ~> HOL.Trueprop
   147     True ~> HOL.True
   148     False ~> HOL.False
   149     op & ~> HOL.conj
   150     op | ~> HOL.disj
   151     op --> ~> HOL.implies
   152     op = ~> HOL.eq
   153     Not ~> HOL.Not
   154     The ~> HOL.The
   155     All ~> HOL.All
   156     Ex ~> HOL.Ex
   157     Ex1 ~> HOL.Ex1
   158     Let ~> HOL.Let
   159     If ~> HOL.If
   160     Ball ~> Set.Ball
   161     Bex ~> Set.Bex
   162     Suc ~> Nat.Suc
   163     Pair ~> Product_Type.Pair
   164     fst ~> Product_Type.fst
   165     snd ~> Product_Type.snd
   166     curry ~> Product_Type.curry
   167     op : ~> Set.member
   168     Collect ~> Set.Collect
   169 
   170 INCOMPATIBILITY.
   171 
   172 * Removed simplifier congruence rule of "prod_case", as has for long
   173 been the case with "split".  INCOMPATIBILITY.
   174 
   175 * Datatype package: theorems generated for executable equality
   176 (class eq) carry proper names and are treated as default code
   177 equations.
   178 
   179 * Removed lemma Option.is_none_none (Duplicate of is_none_def).
   180 INCOMPATIBILITY.
   181 
   182 * List.thy: use various operations from the Haskell prelude when
   183 generating Haskell code.
   184 
   185 * code_simp.ML and method code_simp: simplification with rules determined
   186 by code generator.
   187 
   188 * code generator: do not print function definitions for case
   189 combinators any longer.
   190 
   191 * Multivariate Analysis: Introduced a type class for euclidean space. Most
   192 theorems are now stated in terms of euclidean spaces instead of finite
   193 cartesian products.
   194 
   195   types
   196     real ^ 'n ~>  'a::real_vector
   197               ~>  'a::euclidean_space
   198               ~>  'a::ordered_euclidean_space
   199         (depends on your needs)
   200 
   201   constants
   202      _ $ _        ~> _ $$ _
   203      \<chi> x. _  ~> \<chi>\<chi> x. _
   204      CARD('n)     ~> DIM('a)
   205 
   206 Also note that the indices are now natural numbers and not from some finite
   207 type. Finite cartesian products of euclidean spaces, products of euclidean
   208 spaces the real and complex numbers are instantiated to be euclidean_spaces.
   209 
   210 INCOMPATIBILITY.
   211 
   212 * Probability: Introduced pinfreal as real numbers with infinity. Use pinfreal
   213 as value for measures. Introduces Lebesgue Measure based on the integral in
   214 Multivariate Analysis. Proved Radon Nikodym for arbitrary sigma finite measure
   215 spaces.
   216 
   217  INCOMPATIBILITY.
   218 
   219 * Inductive package: offers new command "inductive_simps" to automatically
   220 derive instantiated and simplified equations for inductive predicates,
   221 similar to inductive_cases.
   222 
   223 * "bij f" is now an abbreviation of "bij_betw f UNIV UNIV". surj_on is a
   224 generalization of surj, and "surj f" is now a abbreviation of "surj_on f UNIV".
   225 The theorems bij_def and surj_def are unchanged.
   226 
   227 *** FOL ***
   228 
   229 * All constant names are now qualified.  INCOMPATIBILITY.
   230 
   231 
   232 *** ZF ***
   233 
   234 * All constant names are now qualified.  INCOMPATIBILITY.
   235 
   236 
   237 *** ML ***
   238 
   239 * Configuration option show_question_marks only affects regular pretty
   240 printing of types and terms, not raw Term.string_of_vname.
   241 
   242 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
   243 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
   244 @{thms} for most purposes.
   245 
   246 * ML structure Unsynchronized never opened, not even in Isar
   247 interaction mode as before.  Old Unsynchronized.set etc. have been
   248 discontinued -- use plain := instead.  This should be *rare* anyway,
   249 since modern tools always work via official context data, notably
   250 configuration options.
   251 
   252 * ML antiquotations @{theory} and @{theory_ref} refer to named
   253 theories from the ancestry of the current context, not any accidental
   254 theory loader state as before.  Potential INCOMPATIBILITY, subtle
   255 change in semantics.
   256 
   257 
   258 *** System ***
   259 
   260 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   261 
   262 
   263 
   264 New in Isabelle2009-2 (June 2010)
   265 ---------------------------------
   266 
   267 *** General ***
   268 
   269 * Authentic syntax for *all* logical entities (type classes, type
   270 constructors, term constants): provides simple and robust
   271 correspondence between formal entities and concrete syntax.  Within
   272 the parse tree / AST representations, "constants" are decorated by
   273 their category (class, type, const) and spelled out explicitly with
   274 their full internal name.
   275 
   276 Substantial INCOMPATIBILITY concerning low-level syntax declarations
   277 and translations (translation rules and translation functions in ML).
   278 Some hints on upgrading:
   279 
   280   - Many existing uses of 'syntax' and 'translations' can be replaced
   281     by more modern 'type_notation', 'notation' and 'abbreviation',
   282     which are independent of this issue.
   283 
   284   - 'translations' require markup within the AST; the term syntax
   285     provides the following special forms:
   286 
   287       CONST c   -- produces syntax version of constant c from context
   288       XCONST c  -- literally c, checked as constant from context
   289       c         -- literally c, if declared by 'syntax'
   290 
   291     Plain identifiers are treated as AST variables -- occasionally the
   292     system indicates accidental variables via the error "rhs contains
   293     extra variables".
   294 
   295     Type classes and type constructors are marked according to their
   296     concrete syntax.  Some old translations rules need to be written
   297     for the "type" category, using type constructor application
   298     instead of pseudo-term application of the default category
   299     "logic".
   300 
   301   - 'parse_translation' etc. in ML may use the following
   302     antiquotations:
   303 
   304       @{class_syntax c}   -- type class c within parse tree / AST
   305       @{term_syntax c}    -- type constructor c within parse tree / AST
   306       @{const_syntax c}   -- ML version of "CONST c" above
   307       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
   308 
   309   - Literal types within 'typed_print_translations', i.e. those *not*
   310     represented as pseudo-terms are represented verbatim.  Use @{class
   311     c} or @{type_name c} here instead of the above syntax
   312     antiquotations.
   313 
   314 Note that old non-authentic syntax was based on unqualified base
   315 names, so all of the above "constant" names would coincide.  Recall
   316 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
   317 diagnose syntax problems.
   318 
   319 * Type constructors admit general mixfix syntax, not just infix.
   320 
   321 * Concrete syntax may be attached to local entities without a proof
   322 body, too.  This works via regular mixfix annotations for 'fix',
   323 'def', 'obtain' etc. or via the explicit 'write' command, which is
   324 similar to the 'notation' command in theory specifications.
   325 
   326 * Discontinued unnamed infix syntax (legacy feature for many years) --
   327 need to specify constant name and syntax separately.  Internal ML
   328 datatype constructors have been renamed from InfixName to Infix etc.
   329 Minor INCOMPATIBILITY.
   330 
   331 * Schematic theorem statements need to be explicitly markup as such,
   332 via commands 'schematic_lemma', 'schematic_theorem',
   333 'schematic_corollary'.  Thus the relevance of the proof is made
   334 syntactically clear, which impacts performance in a parallel or
   335 asynchronous interactive environment.  Minor INCOMPATIBILITY.
   336 
   337 * Use of cumulative prems via "!" in some proof methods has been
   338 discontinued (old legacy feature).
   339 
   340 * References 'trace_simp' and 'debug_simp' have been replaced by
   341 configuration options stored in the context. Enabling tracing (the
   342 case of debugging is similar) in proofs works via
   343 
   344   using [[trace_simp = true]]
   345 
   346 Tracing is then active for all invocations of the simplifier in
   347 subsequent goal refinement steps. Tracing may also still be enabled or
   348 disabled via the ProofGeneral settings menu.
   349 
   350 * Separate commands 'hide_class', 'hide_type', 'hide_const',
   351 'hide_fact' replace the former 'hide' KIND command.  Minor
   352 INCOMPATIBILITY.
   353 
   354 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
   355 more efficient than combinations with -q1 or -q2.
   356 
   357 
   358 *** Pure ***
   359 
   360 * Proofterms record type-class reasoning explicitly, using the
   361 "unconstrain" operation internally.  This eliminates all sort
   362 constraints from a theorem and proof, introducing explicit
   363 OFCLASS-premises.  On the proof term level, this operation is
   364 automatically applied at theorem boundaries, such that closed proofs
   365 are always free of sort constraints.  INCOMPATIBILITY for tools that
   366 inspect proof terms.
   367 
   368 * Local theory specifications may depend on extra type variables that
   369 are not present in the result type -- arguments TYPE('a) :: 'a itself
   370 are added internally.  For example:
   371 
   372   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
   373 
   374 * Predicates of locales introduced by classes carry a mandatory
   375 "class" prefix.  INCOMPATIBILITY.
   376 
   377 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
   378 
   379 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
   380 'class' instead.
   381 
   382 * Command 'code_reflect' allows to incorporate generated ML code into
   383 runtime environment; replaces immature code_datatype antiquotation.
   384 INCOMPATIBILITY.
   385 
   386 * Code generator: simple concept for abstract datatypes obeying
   387 invariants.
   388 
   389 * Code generator: details of internal data cache have no impact on the
   390 user space functionality any longer.
   391 
   392 * Methods "unfold_locales" and "intro_locales" ignore non-locale
   393 subgoals.  This is more appropriate for interpretations with 'where'.
   394 INCOMPATIBILITY.
   395 
   396 * Command 'example_proof' opens an empty proof body.  This allows to
   397 experiment with Isar, without producing any persistent result.
   398 
   399 * Commands 'type_notation' and 'no_type_notation' declare type syntax
   400 within a local theory context, with explicit checking of the
   401 constructors involved (in contrast to the raw 'syntax' versions).
   402 
   403 * Commands 'types' and 'typedecl' now work within a local theory
   404 context -- without introducing dependencies on parameters or
   405 assumptions, which is not possible in Isabelle/Pure.
   406 
   407 * Command 'defaultsort' has been renamed to 'default_sort', it works
   408 within a local theory context.  Minor INCOMPATIBILITY.
   409 
   410 
   411 *** HOL ***
   412 
   413 * Command 'typedef' now works within a local theory context -- without
   414 introducing dependencies on parameters or assumptions, which is not
   415 possible in Isabelle/Pure/HOL.  Note that the logical environment may
   416 contain multiple interpretations of local typedefs (with different
   417 non-emptiness proofs), even in a global theory context.
   418 
   419 * New package for quotient types.  Commands 'quotient_type' and
   420 'quotient_definition' may be used for defining types and constants by
   421 quotient constructions.  An example is the type of integers created by
   422 quotienting pairs of natural numbers:
   423 
   424   fun
   425     intrel :: "(nat * nat) => (nat * nat) => bool"
   426   where
   427     "intrel (x, y) (u, v) = (x + v = u + y)"
   428 
   429   quotient_type int = "nat * nat" / intrel
   430     by (auto simp add: equivp_def expand_fun_eq)
   431 
   432   quotient_definition
   433     "0::int" is "(0::nat, 0::nat)"
   434 
   435 The method "lifting" can be used to lift of theorems from the
   436 underlying "raw" type to the quotient type.  The example
   437 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
   438 construction and provides a reasoning infrastructure for finite sets.
   439 
   440 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
   441 clash with new theory Quotient in Main HOL.
   442 
   443 * Moved the SMT binding into the main HOL session, eliminating
   444 separate HOL-SMT session.
   445 
   446 * List membership infix mem operation is only an input abbreviation.
   447 INCOMPATIBILITY.
   448 
   449 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
   450 for future developements; former Library/Word.thy is still present in
   451 the AFP entry RSAPPS.
   452 
   453 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
   454 longer shadowed.  INCOMPATIBILITY.
   455 
   456 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
   457 INCOMPATIBILITY.
   458 
   459 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
   460 INCOMPATIBILITY.
   461 
   462 * Dropped normalizing_semiring etc; use the facts in semiring classes
   463 instead.  INCOMPATIBILITY.
   464 
   465 * Dropped several real-specific versions of lemmas about floor and
   466 ceiling; use the generic lemmas from theory "Archimedean_Field"
   467 instead.  INCOMPATIBILITY.
   468 
   469   floor_number_of_eq         ~> floor_number_of
   470   le_floor_eq_number_of      ~> number_of_le_floor
   471   le_floor_eq_zero           ~> zero_le_floor
   472   le_floor_eq_one            ~> one_le_floor
   473   floor_less_eq_number_of    ~> floor_less_number_of
   474   floor_less_eq_zero         ~> floor_less_zero
   475   floor_less_eq_one          ~> floor_less_one
   476   less_floor_eq_number_of    ~> number_of_less_floor
   477   less_floor_eq_zero         ~> zero_less_floor
   478   less_floor_eq_one          ~> one_less_floor
   479   floor_le_eq_number_of      ~> floor_le_number_of
   480   floor_le_eq_zero           ~> floor_le_zero
   481   floor_le_eq_one            ~> floor_le_one
   482   floor_subtract_number_of   ~> floor_diff_number_of
   483   floor_subtract_one         ~> floor_diff_one
   484   ceiling_number_of_eq       ~> ceiling_number_of
   485   ceiling_le_eq_number_of    ~> ceiling_le_number_of
   486   ceiling_le_zero_eq         ~> ceiling_le_zero
   487   ceiling_le_eq_one          ~> ceiling_le_one
   488   less_ceiling_eq_number_of  ~> number_of_less_ceiling
   489   less_ceiling_eq_zero       ~> zero_less_ceiling
   490   less_ceiling_eq_one        ~> one_less_ceiling
   491   ceiling_less_eq_number_of  ~> ceiling_less_number_of
   492   ceiling_less_eq_zero       ~> ceiling_less_zero
   493   ceiling_less_eq_one        ~> ceiling_less_one
   494   le_ceiling_eq_number_of    ~> number_of_le_ceiling
   495   le_ceiling_eq_zero         ~> zero_le_ceiling
   496   le_ceiling_eq_one          ~> one_le_ceiling
   497   ceiling_subtract_number_of ~> ceiling_diff_number_of
   498   ceiling_subtract_one       ~> ceiling_diff_one
   499 
   500 * Theory "Finite_Set": various folding_XXX locales facilitate the
   501 application of the various fold combinators on finite sets.
   502 
   503 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
   504 provides abstract red-black tree type which is backed by "RBT_Impl" as
   505 implementation.  INCOMPATIBILTY.
   506 
   507 * Theory Library/Coinductive_List has been removed -- superseded by
   508 AFP/thys/Coinductive.
   509 
   510 * Theory PReal, including the type "preal" and related operations, has
   511 been removed.  INCOMPATIBILITY.
   512 
   513 * Real: new development using Cauchy Sequences.
   514 
   515 * Split off theory "Big_Operators" containing setsum, setprod,
   516 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
   517 
   518 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
   519 "Int" etc.  INCOMPATIBILITY.
   520 
   521 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
   522 
   523 * New set of rules "ac_simps" provides combined assoc / commute
   524 rewrites for all interpretations of the appropriate generic locales.
   525 
   526 * Renamed theory "OrderedGroup" to "Groups" and split theory
   527 "Ring_and_Field" into theories "Rings" and "Fields"; for more
   528 appropriate and more consistent names suitable for name prefixes
   529 within the HOL theories.  INCOMPATIBILITY.
   530 
   531 * Some generic constants have been put to appropriate theories:
   532   - less_eq, less: Orderings
   533   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
   534   - inverse, divide: Rings
   535 INCOMPATIBILITY.
   536 
   537 * More consistent naming of type classes involving orderings (and
   538 lattices):
   539 
   540     lower_semilattice                   ~> semilattice_inf
   541     upper_semilattice                   ~> semilattice_sup
   542 
   543     dense_linear_order                  ~> dense_linorder
   544 
   545     pordered_ab_group_add               ~> ordered_ab_group_add
   546     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
   547     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
   548     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
   549     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
   550     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
   551     pordered_cancel_semiring            ~> ordered_cancel_semiring
   552     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
   553     pordered_comm_ring                  ~> ordered_comm_ring
   554     pordered_comm_semiring              ~> ordered_comm_semiring
   555     pordered_ring                       ~> ordered_ring
   556     pordered_ring_abs                   ~> ordered_ring_abs
   557     pordered_semiring                   ~> ordered_semiring
   558 
   559     ordered_ab_group_add                ~> linordered_ab_group_add
   560     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
   561     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
   562     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
   563     ordered_field                       ~> linordered_field
   564     ordered_field_no_lb                 ~> linordered_field_no_lb
   565     ordered_field_no_ub                 ~> linordered_field_no_ub
   566     ordered_field_dense_linear_order    ~> dense_linordered_field
   567     ordered_idom                        ~> linordered_idom
   568     ordered_ring                        ~> linordered_ring
   569     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
   570     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
   571     ordered_ring_strict                 ~> linordered_ring_strict
   572     ordered_semidom                     ~> linordered_semidom
   573     ordered_semiring                    ~> linordered_semiring
   574     ordered_semiring_1                  ~> linordered_semiring_1
   575     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
   576     ordered_semiring_strict             ~> linordered_semiring_strict
   577 
   578   The following slightly odd type classes have been moved to a
   579   separate theory Library/Lattice_Algebras:
   580 
   581     lordered_ab_group_add               ~> lattice_ab_group_add
   582     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
   583     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
   584     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
   585     lordered_ring                       ~> lattice_ring
   586 
   587 INCOMPATIBILITY.
   588 
   589 * Refined field classes:
   590   - classes division_ring_inverse_zero, field_inverse_zero,
   591     linordered_field_inverse_zero include rule inverse 0 = 0 --
   592     subsumes former division_by_zero class;
   593   - numerous lemmas have been ported from field to division_ring.
   594 INCOMPATIBILITY.
   595 
   596 * Refined algebra theorem collections:
   597   - dropped theorem group group_simps, use algebra_simps instead;
   598   - dropped theorem group ring_simps, use field_simps instead;
   599   - proper theorem collection field_simps subsumes former theorem
   600     groups field_eq_simps and field_simps;
   601   - dropped lemma eq_minus_self_iff which is a duplicate for
   602     equal_neg_zero.
   603 INCOMPATIBILITY.
   604 
   605 * Theory Finite_Set and List: some lemmas have been generalized from
   606 sets to lattices:
   607 
   608   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
   609   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
   610   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
   611   union_Union_fold_union        ~> sup_Sup_fold_sup
   612   Inter_fold_inter              ~> Inf_fold_inf
   613   Union_fold_union              ~> Sup_fold_sup
   614   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
   615   union_UNION_fold_union        ~> sup_SUPR_fold_sup
   616   INTER_fold_inter              ~> INFI_fold_inf
   617   UNION_fold_union              ~> SUPR_fold_sup
   618 
   619 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
   620 replaced by the more convenient lemmas Inf_empty and Sup_empty.
   621 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
   622 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
   623 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
   624 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
   625 
   626 * Reorganized theory Multiset: swapped notation of pointwise and
   627 multiset order:
   628 
   629   - pointwise ordering is instance of class order with standard syntax
   630     <= and <;
   631   - multiset ordering has syntax <=# and <#; partial order properties
   632     are provided by means of interpretation with prefix
   633     multiset_order;
   634   - less duplication, less historical organization of sections,
   635     conversion from associations lists to multisets, rudimentary code
   636     generation;
   637   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
   638     if needed.
   639 
   640 Renamed:
   641 
   642   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
   643   multi_count_ext  ~>  multiset_ext
   644   diff_union_inverse2  ~>  diff_union_cancelR
   645 
   646 INCOMPATIBILITY.
   647 
   648 * Theory Permutation: replaced local "remove" by List.remove1.
   649 
   650 * Code generation: ML and OCaml code is decorated with signatures.
   651 
   652 * Theory List: added transpose.
   653 
   654 * Library/Nat_Bijection.thy is a collection of bijective functions
   655 between nat and other types, which supersedes the older libraries
   656 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
   657 
   658   Constants:
   659   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
   660   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
   661   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
   662   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
   663   Countable.pair_encode           ~> prod_encode
   664   NatIso.prod2nat                 ~> prod_encode
   665   NatIso.nat2prod                 ~> prod_decode
   666   NatIso.sum2nat                  ~> sum_encode
   667   NatIso.nat2sum                  ~> sum_decode
   668   NatIso.list2nat                 ~> list_encode
   669   NatIso.nat2list                 ~> list_decode
   670   NatIso.set2nat                  ~> set_encode
   671   NatIso.nat2set                  ~> set_decode
   672 
   673   Lemmas:
   674   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
   675   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
   676   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
   677   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
   678   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
   679   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
   680   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
   681   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
   682   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
   683   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
   684   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
   685   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
   686   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
   687 
   688 * Sledgehammer:
   689   - Renamed ATP commands:
   690     atp_info     ~> sledgehammer running_atps
   691     atp_kill     ~> sledgehammer kill_atps
   692     atp_messages ~> sledgehammer messages
   693     atp_minimize ~> sledgehammer minimize
   694     print_atps   ~> sledgehammer available_atps
   695     INCOMPATIBILITY.
   696   - Added user's manual ("isabelle doc sledgehammer").
   697   - Added option syntax and "sledgehammer_params" to customize
   698     Sledgehammer's behavior.  See the manual for details.
   699   - Modified the Isar proof reconstruction code so that it produces
   700     direct proofs rather than proofs by contradiction.  (This feature
   701     is still experimental.)
   702   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
   703     full-typed mode.
   704   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
   705 
   706 * Nitpick:
   707   - Added and implemented "binary_ints" and "bits" options.
   708   - Added "std" option and implemented support for nonstandard models.
   709   - Added and implemented "finitize" option to improve the precision
   710     of infinite datatypes based on a monotonicity analysis.
   711   - Added support for quotient types.
   712   - Added support for "specification" and "ax_specification"
   713     constructs.
   714   - Added support for local definitions (for "function" and
   715     "termination" proofs).
   716   - Added support for term postprocessors.
   717   - Optimized "Multiset.multiset" and "FinFun.finfun".
   718   - Improved efficiency of "destroy_constrs" optimization.
   719   - Fixed soundness bugs related to "destroy_constrs" optimization and
   720     record getters.
   721   - Fixed soundness bug related to higher-order constructors.
   722   - Fixed soundness bug when "full_descrs" is enabled.
   723   - Improved precision of set constructs.
   724   - Added "atoms" option.
   725   - Added cache to speed up repeated Kodkod invocations on the same
   726     problems.
   727   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
   728     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
   729     "SAT4J_Light".  INCOMPATIBILITY.
   730   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
   731     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
   732   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
   733 
   734 * Method "induct" now takes instantiations of the form t, where t is not
   735   a variable, as a shorthand for "x == t", where x is a fresh variable.
   736   If this is not intended, t has to be enclosed in parentheses.
   737   By default, the equalities generated by definitional instantiations
   738   are pre-simplified, which may cause parameters of inductive cases
   739   to disappear, or may even delete some of the inductive cases.
   740   Use "induct (no_simp)" instead of "induct" to restore the old
   741   behaviour. The (no_simp) option is also understood by the "cases"
   742   and "nominal_induct" methods, which now perform pre-simplification, too.
   743   INCOMPATIBILITY.
   744 
   745 
   746 *** HOLCF ***
   747 
   748 * Variable names in lemmas generated by the domain package have
   749 changed; the naming scheme is now consistent with the HOL datatype
   750 package.  Some proof scripts may be affected, INCOMPATIBILITY.
   751 
   752 * The domain package no longer defines the function "foo_copy" for
   753 recursive domain "foo".  The reach lemma is now stated directly in
   754 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
   755 be reformulated in terms of "foo_take", INCOMPATIBILITY.
   756 
   757 * Most definedness lemmas generated by the domain package (previously
   758 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
   759 like "foo$x = UU <-> x = UU", which works better as a simp rule.
   760 Proofs that used definedness lemmas as intro rules may break,
   761 potential INCOMPATIBILITY.
   762 
   763 * Induction and casedist rules generated by the domain package now
   764 declare proper case_names (one called "bottom", and one named for each
   765 constructor).  INCOMPATIBILITY.
   766 
   767 * For mutually-recursive domains, separate "reach" and "take_lemma"
   768 rules are generated for each domain, INCOMPATIBILITY.
   769 
   770   foo_bar.reach       ~> foo.reach  bar.reach
   771   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
   772 
   773 * Some lemmas generated by the domain package have been renamed for
   774 consistency with the datatype package, INCOMPATIBILITY.
   775 
   776   foo.ind        ~> foo.induct
   777   foo.finite_ind ~> foo.finite_induct
   778   foo.coind      ~> foo.coinduct
   779   foo.casedist   ~> foo.exhaust
   780   foo.exhaust    ~> foo.nchotomy
   781 
   782 * For consistency with other definition packages, the fixrec package
   783 now generates qualified theorem names, INCOMPATIBILITY.
   784 
   785   foo_simps  ~> foo.simps
   786   foo_unfold ~> foo.unfold
   787   foo_induct ~> foo.induct
   788 
   789 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
   790 method and internal fixrec proofs now use the default simpset instead.
   791 INCOMPATIBILITY.
   792 
   793 * The "contlub" predicate has been removed.  Proof scripts should use
   794 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
   795 
   796 * The "admw" predicate has been removed, INCOMPATIBILITY.
   797 
   798 * The constants cpair, cfst, and csnd have been removed in favor of
   799 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
   800 
   801 
   802 *** ML ***
   803 
   804 * Antiquotations for basic formal entities:
   805 
   806     @{class NAME}         -- type class
   807     @{class_syntax NAME}  -- syntax representation of the above
   808 
   809     @{type_name NAME}     -- logical type
   810     @{type_abbrev NAME}   -- type abbreviation
   811     @{nonterminal NAME}   -- type of concrete syntactic category
   812     @{type_syntax NAME}   -- syntax representation of any of the above
   813 
   814     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
   815     @{const_abbrev NAME}  -- abbreviated constant
   816     @{const_syntax NAME}  -- syntax representation of any of the above
   817 
   818 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
   819 syntax constant (cf. 'syntax' command).
   820 
   821 * Antiquotation @{make_string} inlines a function to print arbitrary
   822 values similar to the ML toplevel.  The result is compiler dependent
   823 and may fall back on "?" in certain situations.
   824 
   825 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
   826 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
   827 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
   828 not work with the asynchronous Isar document model.
   829 
   830 * Configuration options now admit dynamic default values, depending on
   831 the context or even global references.
   832 
   833 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
   834 uses an efficient external library if available (for Poly/ML).
   835 
   836 * Renamed some important ML structures, while keeping the old names
   837 for some time as aliases within the structure Legacy:
   838 
   839   OuterKeyword  ~>  Keyword
   840   OuterLex      ~>  Token
   841   OuterParse    ~>  Parse
   842   OuterSyntax   ~>  Outer_Syntax
   843   PrintMode     ~>  Print_Mode
   844   SpecParse     ~>  Parse_Spec
   845   ThyInfo       ~>  Thy_Info
   846   ThyLoad       ~>  Thy_Load
   847   ThyOutput     ~>  Thy_Output
   848   TypeInfer     ~>  Type_Infer
   849 
   850 Note that "open Legacy" simplifies porting of sources, but forgetting
   851 to remove it again will complicate porting again in the future.
   852 
   853 * Most operations that refer to a global context are named
   854 accordingly, e.g. Simplifier.global_context or
   855 ProofContext.init_global.  There are some situations where a global
   856 context actually works, but under normal circumstances one needs to
   857 pass the proper local context through the code!
   858 
   859 * Discontinued old TheoryDataFun with its copy/init operation -- data
   860 needs to be pure.  Functor Theory_Data_PP retains the traditional
   861 Pretty.pp argument to merge, which is absent in the standard
   862 Theory_Data version.
   863 
   864 * Sorts.certify_sort and derived "cert" operations for types and terms
   865 no longer minimize sorts.  Thus certification at the boundary of the
   866 inference kernel becomes invariant under addition of class relations,
   867 which is an important monotonicity principle.  Sorts are now minimized
   868 in the syntax layer only, at the boundary between the end-user and the
   869 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
   870 explicitly in rare situations.
   871 
   872 * Renamed old-style Drule.standard to Drule.export_without_context, to
   873 emphasize that this is in no way a standard operation.
   874 INCOMPATIBILITY.
   875 
   876 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
   877 usual for resolution.  Rare INCOMPATIBILITY.
   878 
   879 * Renamed varify/unvarify operations to varify_global/unvarify_global
   880 to emphasize that these only work in a global situation (which is
   881 quite rare).
   882 
   883 * Curried take and drop in library.ML; negative length is interpreted
   884 as infinity (as in chop).  Subtle INCOMPATIBILITY.
   885 
   886 * Proof terms: type substitutions on proof constants now use canonical
   887 order of type variables.  INCOMPATIBILITY for tools working with proof
   888 terms.
   889 
   890 * Raw axioms/defs may no longer carry sort constraints, and raw defs
   891 may no longer carry premises.  User-level specifications are
   892 transformed accordingly by Thm.add_axiom/add_def.
   893 
   894 
   895 *** System ***
   896 
   897 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
   898 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
   899 proof terms are enabled unconditionally in the new HOL-Proofs image.
   900 
   901 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
   902 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
   903 respectively.
   904 
   905 * Old lib/scripts/polyml-platform is superseded by the
   906 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
   907 variant, even on a 64 bit machine.  The following example setting
   908 prefers 64 bit if available:
   909 
   910   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
   911 
   912 * The preliminary Isabelle/jEdit application demonstrates the emerging
   913 Isabelle/Scala layer for advanced prover interaction and integration.
   914 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
   915 component.
   916 
   917 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
   918 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
   919 similar to the default assignment of the document preparation system
   920 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
   921 provides some operations for direct access to the font without asking
   922 the user for manual installation.
   923 
   924 
   925 
   926 New in Isabelle2009-1 (December 2009)
   927 -------------------------------------
   928 
   929 *** General ***
   930 
   931 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
   932 one backslash should be used, even in ML sources.
   933 
   934 
   935 *** Pure ***
   936 
   937 * Locale interpretation propagates mixins along the locale hierarchy.
   938 The currently only available mixins are the equations used to map
   939 local definitions to terms of the target domain of an interpretation.
   940 
   941 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
   942 loc" to print all interpretations of locale "loc" in the theory.
   943 Interpretations in proofs are not shown.
   944 
   945 * Thoroughly revised locales tutorial.  New section on conditional
   946 interpretation.
   947 
   948 * On instantiation of classes, remaining undefined class parameters
   949 are formally declared.  INCOMPATIBILITY.
   950 
   951 
   952 *** Document preparation ***
   953 
   954 * New generalized style concept for printing terms: @{foo (style) ...}
   955 instead of @{foo_style style ...}  (old form is still retained for
   956 backward compatibility).  Styles can be also applied for
   957 antiquotations prop, term_type and typeof.
   958 
   959 
   960 *** HOL ***
   961 
   962 * New proof method "smt" for a combination of first-order logic with
   963 equality, linear and nonlinear (natural/integer/real) arithmetic, and
   964 fixed-size bitvectors; there is also basic support for higher-order
   965 features (esp. lambda abstractions).  It is an incomplete decision
   966 procedure based on external SMT solvers using the oracle mechanism;
   967 for the SMT solver Z3, this method is proof-producing.  Certificates
   968 are provided to avoid calling the external solvers solely for
   969 re-checking proofs.  Due to a remote SMT service there is no need for
   970 installing SMT solvers locally.  See src/HOL/SMT.
   971 
   972 * New commands to load and prove verification conditions generated by
   973 the Boogie program verifier or derived systems (e.g. the Verifying C
   974 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
   975 
   976 * New counterexample generator tool 'nitpick' based on the Kodkod
   977 relational model finder.  See src/HOL/Tools/Nitpick and
   978 src/HOL/Nitpick_Examples.
   979 
   980 * New commands 'code_pred' and 'values' to invoke the predicate
   981 compiler and to enumerate values of inductive predicates.
   982 
   983 * A tabled implementation of the reflexive transitive closure.
   984 
   985 * New implementation of quickcheck uses generic code generator;
   986 default generators are provided for all suitable HOL types, records
   987 and datatypes.  Old quickcheck can be re-activated importing theory
   988 Library/SML_Quickcheck.
   989 
   990 * New testing tool Mirabelle for automated proof tools.  Applies
   991 several tools and tactics like sledgehammer, metis, or quickcheck, to
   992 every proof step in a theory.  To be used in batch mode via the
   993 "mirabelle" utility.
   994 
   995 * New proof method "sos" (sum of squares) for nonlinear real
   996 arithmetic (originally due to John Harison). It requires theory
   997 Library/Sum_Of_Squares.  It is not a complete decision procedure but
   998 works well in practice on quantifier-free real arithmetic with +, -,
   999 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1000 inequalities between polynomials.  It makes use of external
  1001 semidefinite programming solvers.  Method "sos" generates a
  1002 certificate that can be pasted into the proof thus avoiding the need
  1003 to call an external tool every time the proof is checked.  See
  1004 src/HOL/Library/Sum_Of_Squares.
  1005 
  1006 * New method "linarith" invokes existing linear arithmetic decision
  1007 procedure only.
  1008 
  1009 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1010 
  1011 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1012 Causes full type information to be output to the ATPs.  This slows
  1013 ATPs down considerably but eliminates a source of unsound "proofs"
  1014 that fail later.
  1015 
  1016 * New method "metisFT": A version of metis that uses full type
  1017 information in order to avoid failures of proof reconstruction.
  1018 
  1019 * New evaluator "approximate" approximates an real valued term using
  1020 the same method as the approximation method.
  1021 
  1022 * Method "approximate" now supports arithmetic expressions as
  1023 boundaries of intervals and implements interval splitting and Taylor
  1024 series expansion.
  1025 
  1026 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1027 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1028 
  1029 * New theory SupInf of the supremum and infimum operators for sets of
  1030 reals.
  1031 
  1032 * New theory Probability, which contains a development of measure
  1033 theory, eventually leading to Lebesgue integration and probability.
  1034 
  1035 * Extended Multivariate Analysis to include derivation and Brouwer's
  1036 fixpoint theorem.
  1037 
  1038 * Reorganization of number theory, INCOMPATIBILITY:
  1039   - new number theory development for nat and int, in theories Divides
  1040     and GCD as well as in new session Number_Theory
  1041   - some constants and facts now suffixed with _nat and _int
  1042     accordingly
  1043   - former session NumberTheory now named Old_Number_Theory, including
  1044     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1045   - moved theory Pocklington from src/HOL/Library to
  1046     src/HOL/Old_Number_Theory
  1047 
  1048 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1049 lcm of finite and infinite sets. It is shown that they form a complete
  1050 lattice.
  1051 
  1052 * Class semiring_div requires superclass no_zero_divisors and proof of
  1053 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1054 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1055 generalized to class semiring_div, subsuming former theorems
  1056 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1057 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1058 INCOMPATIBILITY.
  1059 
  1060 * Refinements to lattice classes and sets:
  1061   - less default intro/elim rules in locale variant, more default
  1062     intro/elim rules in class variant: more uniformity
  1063   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1064     le_inf_iff
  1065   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1066     sup_aci)
  1067   - renamed ACI to inf_sup_aci
  1068   - new class "boolean_algebra"
  1069   - class "complete_lattice" moved to separate theory
  1070     "Complete_Lattice"; corresponding constants (and abbreviations)
  1071     renamed and with authentic syntax:
  1072     Set.Inf ~>    Complete_Lattice.Inf
  1073     Set.Sup ~>    Complete_Lattice.Sup
  1074     Set.INFI ~>   Complete_Lattice.INFI
  1075     Set.SUPR ~>   Complete_Lattice.SUPR
  1076     Set.Inter ~>  Complete_Lattice.Inter
  1077     Set.Union ~>  Complete_Lattice.Union
  1078     Set.INTER ~>  Complete_Lattice.INTER
  1079     Set.UNION ~>  Complete_Lattice.UNION
  1080   - authentic syntax for
  1081     Set.Pow
  1082     Set.image
  1083   - mere abbreviations:
  1084     Set.empty               (for bot)
  1085     Set.UNIV                (for top)
  1086     Set.inter               (for inf, formerly Set.Int)
  1087     Set.union               (for sup, formerly Set.Un)
  1088     Complete_Lattice.Inter  (for Inf)
  1089     Complete_Lattice.Union  (for Sup)
  1090     Complete_Lattice.INTER  (for INFI)
  1091     Complete_Lattice.UNION  (for SUPR)
  1092   - object-logic definitions as far as appropriate
  1093 
  1094 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1095 Un_subset_iff are explicitly deleted as default simp rules; then also
  1096 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1097 deleted to achieve the desired effect.
  1098 
  1099 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1100 rules by default any longer; the same applies to min_max.inf_absorb1
  1101 etc.  INCOMPATIBILITY.
  1102 
  1103 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1104 pred_set_conv by default.  INCOMPATIBILITY.
  1105 
  1106 * Power operations on relations and functions are now one dedicated
  1107 constant "compow" with infix syntax "^^".  Power operation on
  1108 multiplicative monoids retains syntax "^" and is now defined generic
  1109 in class power.  INCOMPATIBILITY.
  1110 
  1111 * Relation composition "R O S" now has a more standard argument order:
  1112 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1113 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1114 break, since the O_assoc rule was not rewritten like this.  Fix using
  1115 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1116 
  1117 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1118 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1119 INCOMPATIBILITY.
  1120 
  1121 * Most rules produced by inductive and datatype package have mandatory
  1122 prefixes.  INCOMPATIBILITY.
  1123 
  1124 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1125 the attribute of the same name.  Each of the theorems in the list
  1126 DERIV_intros assumes composition with an additional function and
  1127 matches a variable to the derivative, which has to be solved by the
  1128 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1129 of most elementary terms.  Former Maclauren.DERIV_tac and
  1130 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1131 INCOMPATIBILITY.
  1132 
  1133 * Code generator attributes follow the usual underscore convention:
  1134     code_unfold     replaces    code unfold
  1135     code_post       replaces    code post
  1136     etc.
  1137   INCOMPATIBILITY.
  1138 
  1139 * Renamed methods:
  1140     sizechange -> size_change
  1141     induct_scheme -> induction_schema
  1142   INCOMPATIBILITY.
  1143 
  1144 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1145 INCOMPATIBILITY, use "undefined" directly.
  1146 
  1147 * Renamed theorems:
  1148     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1149     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1150     Suc_plus1 -> Suc_eq_plus1
  1151     *anti_sym -> *antisym*
  1152     vector_less_eq_def -> vector_le_def
  1153   INCOMPATIBILITY.
  1154 
  1155 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1156 INCOMPATIBILITY.
  1157 
  1158 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1159 INCOMPATIBILITY.
  1160 
  1161 
  1162 *** HOLCF ***
  1163 
  1164 * Theory Representable defines a class "rep" of domains that are
  1165 representable (via an ep-pair) in the universal domain type "udom".
  1166 Instances are provided for all type constructors defined in HOLCF.
  1167 
  1168 * The 'new_domain' command is a purely definitional version of the
  1169 domain package, for representable domains.  Syntax is identical to the
  1170 old domain package.  The 'new_domain' package also supports indirect
  1171 recursion using previously-defined type constructors.  See
  1172 src/HOLCF/ex/New_Domain.thy for examples.
  1173 
  1174 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1175 on the left-hand side of an equation, and then performs
  1176 simplification.  Rewriting is done using rules declared with the
  1177 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1178 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1179 
  1180 * The pattern-match compiler in 'fixrec' can now handle constructors
  1181 with HOL function types.  Pattern-match combinators for the Pair
  1182 constructor are pre-configured.
  1183 
  1184 * The 'fixrec' package now produces better fixed-point induction rules
  1185 for mutually-recursive definitions:  Induction rules have conclusions
  1186 of the form "P foo bar" instead of "P <foo, bar>".
  1187 
  1188 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1189 been renamed to "below".  The name "below" now replaces "less" in many
  1190 theorem names.  (Legacy theorem names using "less" are still supported
  1191 as well.)
  1192 
  1193 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1194 patterns can be used to generate strictness rules, or to make
  1195 functions more strict (much like the bang-patterns supported by the
  1196 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1197 examples.
  1198 
  1199 
  1200 *** ML ***
  1201 
  1202 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1203 errors and run-time exceptions, including detailed source positions.
  1204 
  1205 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1206 identified entries, with some additional information such as source
  1207 position, logical grouping etc.
  1208 
  1209 * Theory and context data is now introduced by the simplified and
  1210 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1211 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1212 copy operation) is still available for some time.
  1213 
  1214 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1215 provides a high-level programming interface to synchronized state
  1216 variables with atomic update.  This works via pure function
  1217 application within a critical section -- its runtime should be as
  1218 short as possible; beware of deadlocks if critical code is nested,
  1219 either directly or indirectly via other synchronized variables!
  1220 
  1221 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1222 wraps raw ML references, explicitly indicating their non-thread-safe
  1223 behaviour.  The Isar toplevel keeps this structure open, to
  1224 accommodate Proof General as well as quick and dirty interactive
  1225 experiments with references.
  1226 
  1227 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1228 parallel tactical reasoning.
  1229 
  1230 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1231 are similar to SUBPROOF, but are slightly more flexible: only the
  1232 specified parts of the subgoal are imported into the context, and the
  1233 body tactic may introduce new subgoals and schematic variables.
  1234 
  1235 * Old tactical METAHYPS, which does not observe the proof context, has
  1236 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1237 or Subgoal.FOCUS etc.
  1238 
  1239 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1240 functors have their own ML name space there is no point to mark them
  1241 separately.)  Minor INCOMPATIBILITY.
  1242 
  1243 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1244 
  1245 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1246 INCOMPATIBILITY.
  1247 
  1248 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1249 mode, which avoids critical setmp.
  1250 
  1251 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1252 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1253 Attrib/Method.setup introduced in Isabelle2009.
  1254 
  1255 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1256 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1257 last resort.  INCOMPATIBILITY.
  1258 
  1259 * Display.pretty_thm now requires a proper context (cf. former
  1260 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1261 or even Display.pretty_thm_without_context as last resort.
  1262 INCOMPATIBILITY.
  1263 
  1264 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1265 Syntax.pretty_typ/term directly, preferably with proper context
  1266 instead of global theory.
  1267 
  1268 
  1269 *** System ***
  1270 
  1271 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1272 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1273 usedir option -q.
  1274 
  1275 * Support for additional "Isabelle components" via etc/components, see
  1276 also the system manual.
  1277 
  1278 * The isabelle makeall tool now operates on all components with
  1279 IsaMakefile, not just hardwired "logics".
  1280 
  1281 * Removed "compress" option from isabelle-process and isabelle usedir;
  1282 this is always enabled.
  1283 
  1284 * Discontinued support for Poly/ML 4.x versions.
  1285 
  1286 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  1287 on a given logic image.  This requires the lighttpd webserver and is
  1288 currently supported on Linux only.
  1289 
  1290 
  1291 
  1292 New in Isabelle2009 (April 2009)
  1293 --------------------------------
  1294 
  1295 *** General ***
  1296 
  1297 * Simplified main Isabelle executables, with less surprises on
  1298 case-insensitive file-systems (such as Mac OS).
  1299 
  1300   - The main Isabelle tool wrapper is now called "isabelle" instead of
  1301     "isatool."
  1302 
  1303   - The former "isabelle" alias for "isabelle-process" has been
  1304     removed (should rarely occur to regular users).
  1305 
  1306   - The former "isabelle-interface" and its alias "Isabelle" have been
  1307     removed (interfaces are now regular Isabelle tools).
  1308 
  1309 Within scripts and make files, the Isabelle environment variables
  1310 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  1311 respectively.  (The latter are still available as legacy feature.)
  1312 
  1313 The old isabelle-interface wrapper could react in confusing ways if
  1314 the interface was uninstalled or changed otherwise.  Individual
  1315 interface tool configuration is now more explicit, see also the
  1316 Isabelle system manual.  In particular, Proof General is now available
  1317 via "isabelle emacs".
  1318 
  1319 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  1320 purge installed copies of Isabelle executables and re-run "isabelle
  1321 install -p ...", or use symlinks.
  1322 
  1323 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  1324 old ~/isabelle, which was slightly non-standard and apt to cause
  1325 surprises on case-insensitive file-systems (such as Mac OS).
  1326 
  1327 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  1328 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  1329 care is required when using older releases of Isabelle.  Note that
  1330 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  1331 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  1332 
  1333 * Proofs of fully specified statements are run in parallel on
  1334 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  1335 a regular 4-core machine, if the initial heap space is made reasonably
  1336 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  1337 
  1338 * The main reference manuals ("isar-ref", "implementation", and
  1339 "system") have been updated and extended.  Formally checked references
  1340 as hyperlinks are now available uniformly.
  1341 
  1342 
  1343 *** Pure ***
  1344 
  1345 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  1346 respects.  The most important changes are listed below.  See the
  1347 Tutorial on Locales ("locales" manual) for details.
  1348 
  1349 - In locale expressions, instantiation replaces renaming.  Parameters
  1350 must be declared in a for clause.  To aid compatibility with previous
  1351 parameter inheritance, in locale declarations, parameters that are not
  1352 'touched' (instantiation position "_" or omitted) are implicitly added
  1353 with their syntax at the beginning of the for clause.
  1354 
  1355 - Syntax from abbreviations and definitions in locales is available in
  1356 locale expressions and context elements.  The latter is particularly
  1357 useful in locale declarations.
  1358 
  1359 - More flexible mechanisms to qualify names generated by locale
  1360 expressions.  Qualifiers (prefixes) may be specified in locale
  1361 expressions, and can be marked as mandatory (syntax: "name!:") or
  1362 optional (syntax "name?:").  The default depends for plain "name:"
  1363 depends on the situation where a locale expression is used: in
  1364 commands 'locale' and 'sublocale' prefixes are optional, in
  1365 'interpretation' and 'interpret' prefixes are mandatory.  The old
  1366 implicit qualifiers derived from the parameter names of a locale are
  1367 no longer generated.
  1368 
  1369 - Command "sublocale l < e" replaces "interpretation l < e".  The
  1370 instantiation clause in "interpretation" and "interpret" (square
  1371 brackets) is no longer available.  Use locale expressions.
  1372 
  1373 - When converting proof scripts, mandatory qualifiers in
  1374 'interpretation' and 'interpret' should be retained by default, even
  1375 if this is an INCOMPATIBILITY compared to former behavior.  In the
  1376 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  1377 in locale expressions range over a single locale instance only.
  1378 
  1379 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  1380 In existing theorem specifications replace the includes element by the
  1381 respective context elements of the included locale, omitting those
  1382 that are already present in the theorem specification.  Multiple
  1383 assume elements of a locale should be replaced by a single one
  1384 involving the locale predicate.  In the proof body, declarations (most
  1385 notably theorems) may be regained by interpreting the respective
  1386 locales in the proof context as required (command "interpret").
  1387 
  1388 If using "includes" in replacement of a target solely because the
  1389 parameter types in the theorem are not as general as in the target,
  1390 consider declaring a new locale with additional type constraints on
  1391 the parameters (context element "constrains").
  1392 
  1393 - Discontinued "locale (open)".  INCOMPATIBILITY.
  1394 
  1395 - Locale interpretation commands no longer attempt to simplify goal.
  1396 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  1397 methods intro_locales and unfold_locales to clarify.
  1398 
  1399 - Locale interpretation commands no longer accept interpretation
  1400 attributes.  INCOMPATIBILITY.
  1401 
  1402 * Class declaration: so-called "base sort" must not be given in import
  1403 list any longer, but is inferred from the specification.  Particularly
  1404 in HOL, write
  1405 
  1406     class foo = ...
  1407 
  1408 instead of
  1409 
  1410     class foo = type + ...
  1411 
  1412 * Class target: global versions of theorems stemming do not carry a
  1413 parameter prefix any longer.  INCOMPATIBILITY.
  1414 
  1415 * Class 'instance' command no longer accepts attached definitions.
  1416 INCOMPATIBILITY, use proper 'instantiation' target instead.
  1417 
  1418 * Recovered hiding of consts, which was accidentally broken in
  1419 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  1420 makes c inaccessible; consider using ``hide (open) const c'' instead.
  1421 
  1422 * Slightly more coherent Pure syntax, with updated documentation in
  1423 isar-ref manual.  Removed locales meta_term_syntax and
  1424 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  1425 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  1426 directly in regular applications.
  1427 
  1428 * There is a new syntactic category "float_const" for signed decimal
  1429 fractions (e.g. 123.45 or -123.45).
  1430 
  1431 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  1432 interface with 'setup' command instead.
  1433 
  1434 * Command 'local_setup' is similar to 'setup', but operates on a local
  1435 theory context.
  1436 
  1437 * The 'axiomatization' command now only works within a global theory
  1438 context.  INCOMPATIBILITY.
  1439 
  1440 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  1441 hypotheses.  Sorts required in the course of reasoning need to be
  1442 covered by the constraints in the initial statement, completed by the
  1443 type instance information of the background theory.  Non-trivial sort
  1444 hypotheses, which rarely occur in practice, may be specified via
  1445 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  1446 
  1447   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  1448 
  1449 The result contains an implicit sort hypotheses as before --
  1450 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  1451 normalization.
  1452 
  1453 * Generalized Isar history, with support for linear undo, direct state
  1454 addressing etc.
  1455 
  1456 * Changed defaults for unify configuration options:
  1457 
  1458   unify_trace_bound = 50 (formerly 25)
  1459   unify_search_bound = 60 (formerly 30)
  1460 
  1461 * Different bookkeeping for code equations (INCOMPATIBILITY):
  1462 
  1463   a) On theory merge, the last set of code equations for a particular
  1464      constant is taken (in accordance with the policy applied by other
  1465      parts of the code generator framework).
  1466 
  1467   b) Code equations stemming from explicit declarations (e.g. code
  1468      attribute) gain priority over default code equations stemming
  1469      from definition, primrec, fun etc.
  1470 
  1471 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  1472 
  1473 * Unified theorem tables for both code generators.  Thus [code
  1474 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  1475 
  1476 * Command 'find_consts' searches for constants based on type and name
  1477 patterns, e.g.
  1478 
  1479     find_consts "_ => bool"
  1480 
  1481 By default, matching is against subtypes, but it may be restricted to
  1482 the whole type.  Searching by name is possible.  Multiple queries are
  1483 conjunctive and queries may be negated by prefixing them with a
  1484 hyphen:
  1485 
  1486     find_consts strict: "_ => bool" name: "Int" -"int => int"
  1487 
  1488 * New 'find_theorems' criterion "solves" matches theorems that
  1489 directly solve the current goal (modulo higher-order unification).
  1490 
  1491 * Auto solve feature for main theorem statements: whenever a new goal
  1492 is stated, "find_theorems solves" is called; any theorems that could
  1493 solve the lemma directly are listed as part of the goal state.
  1494 Cf. associated options in Proof General Isabelle settings menu,
  1495 enabled by default, with reasonable timeout for pathological cases of
  1496 higher-order unification.
  1497 
  1498 
  1499 *** Document preparation ***
  1500 
  1501 * Antiquotation @{lemma} now imitates a regular terminal proof,
  1502 demanding keyword 'by' and supporting the full method expression
  1503 syntax just like the Isar command 'by'.
  1504 
  1505 
  1506 *** HOL ***
  1507 
  1508 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  1509 points Main and Complex_Main remain as before.
  1510 
  1511 * Logic image HOL-Plain provides a minimal HOL with the most important
  1512 tools available (inductive, datatype, primrec, ...).  This facilitates
  1513 experimentation and tool development.  Note that user applications
  1514 (and library theories) should never refer to anything below theory
  1515 Main, as before.
  1516 
  1517 * Logic image HOL-Main stops at theory Main, and thus facilitates
  1518 experimentation due to shorter build times.
  1519 
  1520 * Logic image HOL-NSA contains theories of nonstandard analysis which
  1521 were previously part of former HOL-Complex.  Entry point Hyperreal
  1522 remains valid, but theories formerly using Complex_Main should now use
  1523 new entry point Hypercomplex.
  1524 
  1525 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  1526 Posix processes.  Avoids potentially expensive forking of the ML
  1527 process.  New thread-based implementation also works on non-Unix
  1528 platforms (Cygwin).  Provers are no longer hardwired, but defined
  1529 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  1530 commands are covered in the isar-ref manual.
  1531 
  1532 * Wrapper scripts for remote SystemOnTPTP service allows to use
  1533 sledgehammer without local ATP installation (Vampire etc.). Other
  1534 provers may be included via suitable ML wrappers, see also
  1535 src/HOL/ATP_Linkup.thy.
  1536 
  1537 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  1538 menu.
  1539 
  1540 * The metis method no longer fails because the theorem is too trivial
  1541 (contains the empty clause).
  1542 
  1543 * The metis method now fails in the usual manner, rather than raising
  1544 an exception, if it determines that it cannot prove the theorem.
  1545 
  1546 * Method "coherent" implements a prover for coherent logic (see also
  1547 src/Tools/coherent.ML).
  1548 
  1549 * Constants "undefined" and "default" replace "arbitrary".  Usually
  1550 "undefined" is the right choice to replace "arbitrary", though
  1551 logically there is no difference.  INCOMPATIBILITY.
  1552 
  1553 * Command "value" now integrates different evaluation mechanisms.  The
  1554 result of the first successful evaluation mechanism is printed.  In
  1555 square brackets a particular named evaluation mechanisms may be
  1556 specified (currently, [SML], [code] or [nbe]).  See further
  1557 src/HOL/ex/Eval_Examples.thy.
  1558 
  1559 * Normalization by evaluation now allows non-leftlinear equations.
  1560 Declare with attribute [code nbe].
  1561 
  1562 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  1563 as the structured Isar versions "cases" and "induct", cf. the
  1564 corresponding "cases" and "induct" attributes.  Mutual induction rules
  1565 are now presented as a list of individual projections
  1566 (e.g. foo_bar.inducts for types foo and bar); the old format with
  1567 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  1568 rare situations a different rule is selected --- notably nested tuple
  1569 elimination instead of former prod.exhaust: use explicit (case_tac t
  1570 rule: prod.exhaust) here.
  1571 
  1572 * Attributes "cases", "induct", "coinduct" support "del" option.
  1573 
  1574 * Removed fact "case_split_thm", which duplicates "case_split".
  1575 
  1576 * The option datatype has been moved to a new theory Option.  Renamed
  1577 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  1578 
  1579 * New predicate "strict_mono" classifies strict functions on partial
  1580 orders.  With strict functions on linear orders, reasoning about
  1581 (in)equalities is facilitated by theorems "strict_mono_eq",
  1582 "strict_mono_less_eq" and "strict_mono_less".
  1583 
  1584 * Some set operations are now proper qualified constants with
  1585 authentic syntax.  INCOMPATIBILITY:
  1586 
  1587     op Int ~>   Set.Int
  1588     op Un ~>    Set.Un
  1589     INTER ~>    Set.INTER
  1590     UNION ~>    Set.UNION
  1591     Inter ~>    Set.Inter
  1592     Union ~>    Set.Union
  1593     {} ~>       Set.empty
  1594     UNIV ~>     Set.UNIV
  1595 
  1596 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  1597 theory Set.
  1598 
  1599 * Auxiliary class "itself" has disappeared -- classes without any
  1600 parameter are treated as expected by the 'class' command.
  1601 
  1602 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  1603 
  1604 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  1605 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  1606 
  1607 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  1608 method "approximation".  It proves formulas on real values by using
  1609 interval arithmetic.  In the formulas are also the transcendental
  1610 functions sin, cos, tan, atan, ln, exp and the constant pi are
  1611 allowed. For examples see
  1612 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  1613 
  1614 * Theory "Reflection" now resides in HOL/Library.
  1615 
  1616 * Entry point to Word library now simply named "Word".
  1617 INCOMPATIBILITY.
  1618 
  1619 * Made source layout more coherent with logical distribution
  1620 structure:
  1621 
  1622     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  1623     src/HOL/Library/Code_Message.thy ~> src/HOL/
  1624     src/HOL/Library/GCD.thy ~> src/HOL/
  1625     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  1626     src/HOL/Library/Parity.thy ~> src/HOL/
  1627     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  1628     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  1629     src/HOL/Real/Lubs.thy ~> src/HOL/
  1630     src/HOL/Real/PReal.thy ~> src/HOL/
  1631     src/HOL/Real/Rational.thy ~> src/HOL/
  1632     src/HOL/Real/RComplete.thy ~> src/HOL/
  1633     src/HOL/Real/RealDef.thy ~> src/HOL/
  1634     src/HOL/Real/RealPow.thy ~> src/HOL/
  1635     src/HOL/Real/Real.thy ~> src/HOL/
  1636     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  1637     src/HOL/Complex/Complex.thy ~> src/HOL/
  1638     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  1639     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  1640     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  1641     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  1642     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  1643     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  1644     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  1645     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  1646     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  1647     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  1648     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  1649     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  1650     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  1651     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  1652     src/HOL/Real/Float ~> src/HOL/Library/
  1653     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  1654     src/HOL/Real/RealVector.thy ~> src/HOL/
  1655 
  1656     src/HOL/arith_data.ML ~> src/HOL/Tools
  1657     src/HOL/hologic.ML ~> src/HOL/Tools
  1658     src/HOL/simpdata.ML ~> src/HOL/Tools
  1659     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  1660     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  1661     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  1662     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  1663     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  1664     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  1665     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  1666 
  1667     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  1668     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  1669     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  1670     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  1671     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  1672     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  1673 
  1674 * If methods "eval" and "evaluation" encounter a structured proof
  1675 state with !!/==>, only the conclusion is evaluated to True (if
  1676 possible), avoiding strange error messages.
  1677 
  1678 * Method "sizechange" automates termination proofs using (a
  1679 modification of) the size-change principle.  Requires SAT solver.  See
  1680 src/HOL/ex/Termination.thy for examples.
  1681 
  1682 * Simplifier: simproc for let expressions now unfolds if bound
  1683 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  1684 
  1685 * Method "arith": Linear arithmetic now ignores all inequalities when
  1686 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  1687 
  1688 * New attribute "arith" for facts that should always be used
  1689 automatically by arithmetic. It is intended to be used locally in
  1690 proofs, e.g.
  1691 
  1692   assumes [arith]: "x > 0"
  1693 
  1694 Global usage is discouraged because of possible performance impact.
  1695 
  1696 * New classes "top" and "bot" with corresponding operations "top" and
  1697 "bot" in theory Orderings; instantiation of class "complete_lattice"
  1698 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  1699 
  1700 * Changed definition lemma "less_fun_def" in order to provide an
  1701 instance for preorders on functions; use lemma "less_le" instead.
  1702 INCOMPATIBILITY.
  1703 
  1704 * Theory Orderings: class "wellorder" moved here, with explicit
  1705 induction rule "less_induct" as assumption.  For instantiation of
  1706 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  1707 INCOMPATIBILITY.
  1708 
  1709 * Theory Orderings: added class "preorder" as superclass of "order".
  1710 INCOMPATIBILITY: Instantiation proofs for order, linorder
  1711 etc. slightly changed.  Some theorems named order_class.* now named
  1712 preorder_class.*.
  1713 
  1714 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  1715 "diag" to "Id_on".
  1716 
  1717 * Theory Finite_Set: added a new fold combinator of type
  1718 
  1719   ('a => 'b => 'b) => 'b => 'a set => 'b
  1720 
  1721 Occasionally this is more convenient than the old fold combinator
  1722 which is now defined in terms of the new one and renamed to
  1723 fold_image.
  1724 
  1725 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  1726 and "ring_simps" have been replaced by "algebra_simps" (which can be
  1727 extended with further lemmas!).  At the moment both still exist but
  1728 the former will disappear at some point.
  1729 
  1730 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  1731 class recpower.  Type-specific simp rules for various recpower types
  1732 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  1733 
  1734 rat_power_0    -> power_0
  1735 rat_power_Suc  -> power_Suc
  1736 realpow_0      -> power_0
  1737 realpow_Suc    -> power_Suc
  1738 complexpow_0   -> power_0
  1739 complexpow_Suc -> power_Suc
  1740 power_poly_0   -> power_0
  1741 power_poly_Suc -> power_Suc
  1742 
  1743 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  1744 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  1745 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  1746 of lemmas from Divides has been generalized from nat to class
  1747 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  1748 renames resulting from duplicate elimination:
  1749 
  1750     dvd_def_mod ~>          dvd_eq_mod_eq_0
  1751     zero_dvd_iff ~>         dvd_0_left_iff
  1752     dvd_0 ~>                dvd_0_right
  1753     DIVISION_BY_ZERO_DIV ~> div_by_0
  1754     DIVISION_BY_ZERO_MOD ~> mod_by_0
  1755     mult_div ~>             div_mult_self2_is_id
  1756     mult_mod ~>             mod_mult_self2_is_0
  1757 
  1758 * Theory IntDiv: removed many lemmas that are instances of class-based
  1759 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  1760 rename old lemmas as follows:
  1761 
  1762 dvd_diff               -> nat_dvd_diff
  1763 dvd_zminus_iff         -> dvd_minus_iff
  1764 mod_add1_eq            -> mod_add_eq
  1765 mod_mult1_eq           -> mod_mult_right_eq
  1766 mod_mult1_eq'          -> mod_mult_left_eq
  1767 mod_mult_distrib_mod   -> mod_mult_eq
  1768 nat_mod_add_left_eq    -> mod_add_left_eq
  1769 nat_mod_add_right_eq   -> mod_add_right_eq
  1770 nat_mod_div_trivial    -> mod_div_trivial
  1771 nat_mod_mod_trivial    -> mod_mod_trivial
  1772 zdiv_zadd_self1        -> div_add_self1
  1773 zdiv_zadd_self2        -> div_add_self2
  1774 zdiv_zmult_self1       -> div_mult_self2_is_id
  1775 zdiv_zmult_self2       -> div_mult_self1_is_id
  1776 zdvd_triv_left         -> dvd_triv_left
  1777 zdvd_triv_right        -> dvd_triv_right
  1778 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  1779 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  1780 zmod_zadd_left_eq      -> mod_add_left_eq
  1781 zmod_zadd_right_eq     -> mod_add_right_eq
  1782 zmod_zadd_self1        -> mod_add_self1
  1783 zmod_zadd_self2        -> mod_add_self2
  1784 zmod_zadd1_eq          -> mod_add_eq
  1785 zmod_zdiff1_eq         -> mod_diff_eq
  1786 zmod_zdvd_zmod         -> mod_mod_cancel
  1787 zmod_zmod_cancel       -> mod_mod_cancel
  1788 zmod_zmult_self1       -> mod_mult_self2_is_0
  1789 zmod_zmult_self2       -> mod_mult_self1_is_0
  1790 zmod_1                 -> mod_by_1
  1791 zdiv_1                 -> div_by_1
  1792 zdvd_abs1              -> abs_dvd_iff
  1793 zdvd_abs2              -> dvd_abs_iff
  1794 zdvd_refl              -> dvd_refl
  1795 zdvd_trans             -> dvd_trans
  1796 zdvd_zadd              -> dvd_add
  1797 zdvd_zdiff             -> dvd_diff
  1798 zdvd_zminus_iff        -> dvd_minus_iff
  1799 zdvd_zminus2_iff       -> minus_dvd_iff
  1800 zdvd_zmultD            -> dvd_mult_right
  1801 zdvd_zmultD2           -> dvd_mult_left
  1802 zdvd_zmult_mono        -> mult_dvd_mono
  1803 zdvd_0_right           -> dvd_0_right
  1804 zdvd_0_left            -> dvd_0_left_iff
  1805 zdvd_1_left            -> one_dvd
  1806 zminus_dvd_iff         -> minus_dvd_iff
  1807 
  1808 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  1809 
  1810 * The real numbers offer decimal input syntax: 12.34 is translated
  1811 into 1234/10^2. This translation is not reversed upon output.
  1812 
  1813 * Theory Library/Polynomial defines an abstract type 'a poly of
  1814 univariate polynomials with coefficients of type 'a.  In addition to
  1815 the standard ring operations, it also supports div and mod.  Code
  1816 generation is also supported, using list-style constructors.
  1817 
  1818 * Theory Library/Inner_Product defines a class of real_inner for real
  1819 inner product spaces, with an overloaded operation inner :: 'a => 'a
  1820 => real.  Class real_inner is a subclass of real_normed_vector from
  1821 theory RealVector.
  1822 
  1823 * Theory Library/Product_Vector provides instances for the product
  1824 type 'a * 'b of several classes from RealVector and Inner_Product.
  1825 Definitions of addition, subtraction, scalar multiplication, norms,
  1826 and inner products are included.
  1827 
  1828 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  1829 addition to the field operations, numerals and case syntax are also
  1830 supported.
  1831 
  1832 * Theory Library/Diagonalize provides constructive version of Cantor's
  1833 first diagonalization argument.
  1834 
  1835 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  1836 zlcm (for int); carried together from various gcd/lcm developements in
  1837 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  1838 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  1839 may recover tupled syntax as follows:
  1840 
  1841     hide (open) const gcd
  1842     abbreviation gcd where
  1843       "gcd == (%(a, b). GCD.gcd a b)"
  1844     notation (output)
  1845       GCD.gcd ("gcd '(_, _')")
  1846 
  1847 The same works for lcm, zgcd, zlcm.
  1848 
  1849 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  1850 instantiations for algebraic structures.  Removed some duplicate
  1851 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  1852 
  1853 * ML antiquotation @{code} takes a constant as argument and generates
  1854 corresponding code in background and inserts name of the corresponding
  1855 resulting ML value/function/datatype constructor binding in place.
  1856 All occurrences of @{code} with a single ML block are generated
  1857 simultaneously.  Provides a generic and safe interface for
  1858 instrumentalizing code generation.  See
  1859 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  1860 In future you ought to refrain from ad-hoc compiling generated SML
  1861 code on the ML toplevel.  Note that (for technical reasons) @{code}
  1862 cannot refer to constants for which user-defined serializations are
  1863 set.  Refer to the corresponding ML counterpart directly in that
  1864 cases.
  1865 
  1866 * Command 'rep_datatype': instead of theorem names the command now
  1867 takes a list of terms denoting the constructors of the type to be
  1868 represented as datatype.  The characteristic theorems have to be
  1869 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  1870 have disappeared in favour of existing ones:
  1871 
  1872     unit_induct                 ~> unit.induct
  1873     prod_induct                 ~> prod.induct
  1874     sum_induct                  ~> sum.induct
  1875     Suc_Suc_eq                  ~> nat.inject
  1876     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  1877 
  1878 
  1879 *** HOL-Algebra ***
  1880 
  1881 * New locales for orders and lattices where the equivalence relation
  1882 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  1883 locales use a record structure with field eq for the equivalence.
  1884 
  1885 * New theory of factorial domains.
  1886 
  1887 * Units_l_inv and Units_r_inv are now simp rules by default.
  1888 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  1889 and/or r_inv will now also require deletion of these lemmas.
  1890 
  1891 * Renamed the following theorems, INCOMPATIBILITY:
  1892 
  1893 UpperD ~> Upper_memD
  1894 LowerD ~> Lower_memD
  1895 least_carrier ~> least_closed
  1896 greatest_carrier ~> greatest_closed
  1897 greatest_Lower_above ~> greatest_Lower_below
  1898 one_zero ~> carrier_one_zero
  1899 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  1900 
  1901 
  1902 *** HOL-Nominal ***
  1903 
  1904 * Nominal datatypes can now contain type-variables.
  1905 
  1906 * Commands 'nominal_inductive' and 'equivariance' work with local
  1907 theory targets.
  1908 
  1909 * Nominal primrec can now works with local theory targets and its
  1910 specification syntax now conforms to the general format as seen in
  1911 'inductive' etc.
  1912 
  1913 * Method "perm_simp" honours the standard simplifier attributes
  1914 (no_asm), (no_asm_use) etc.
  1915 
  1916 * The new predicate #* is defined like freshness, except that on the
  1917 left hand side can be a set or list of atoms.
  1918 
  1919 * Experimental command 'nominal_inductive2' derives strong induction
  1920 principles for inductive definitions.  In contrast to
  1921 'nominal_inductive', which can only deal with a fixed number of
  1922 binders, it can deal with arbitrary expressions standing for sets of
  1923 atoms to be avoided.  The only inductive definition we have at the
  1924 moment that needs this generalisation is the typing rule for Lets in
  1925 the algorithm W:
  1926 
  1927  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  1928  -----------------------------------------------------------------
  1929          Gamma |- Let x be t1 in t2 : T2
  1930 
  1931 In this rule one wants to avoid all the binders that are introduced by
  1932 "close Gamma T1".  We are looking for other examples where this
  1933 feature might be useful.  Please let us know.
  1934 
  1935 
  1936 *** HOLCF ***
  1937 
  1938 * Reimplemented the simplification procedure for proving continuity
  1939 subgoals.  The new simproc is extensible; users can declare additional
  1940 continuity introduction rules with the attribute [cont2cont].
  1941 
  1942 * The continuity simproc now uses a different introduction rule for
  1943 solving continuity subgoals on terms with lambda abstractions.  In
  1944 some rare cases the new simproc may fail to solve subgoals that the
  1945 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  1946 Potential INCOMPATIBILITY.
  1947 
  1948 * Command 'fixrec': specification syntax now conforms to the general
  1949 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  1950 examples.  INCOMPATIBILITY.
  1951 
  1952 
  1953 *** ZF ***
  1954 
  1955 * Proof of Zorn's Lemma for partial orders.
  1956 
  1957 
  1958 *** ML ***
  1959 
  1960 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  1961 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  1962 depends on multithreading, so timouts will not work before Poly/ML
  1963 5.2.1!
  1964 
  1965 * High-level support for concurrent ML programming, see
  1966 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  1967 particularly convenient to organize independent functional
  1968 computations.  The concept of "synchronized variables" provides a
  1969 higher-order interface for components with shared state, avoiding the
  1970 delicate details of mutexes and condition variables.  (Requires
  1971 Poly/ML 5.2.1 or later.)
  1972 
  1973 * ML bindings produced via Isar commands are stored within the Isar
  1974 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  1975 become thread-safe and work with undo as expected (concerning
  1976 top-level bindings, not side-effects on global references).
  1977 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  1978 compiler at runtime; really global bindings need to be given outside a
  1979 theory.  (Requires Poly/ML 5.2 or later.)
  1980 
  1981 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  1982 context.  Top-level ML bindings are stored within the proof context in
  1983 a purely sequential fashion, disregarding the nested proof structure.
  1984 ML bindings introduced by 'ML_prf' are discarded at the end of the
  1985 proof.  (Requires Poly/ML 5.2 or later.)
  1986 
  1987 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  1988 and Method.setup, as well as Isar commands 'attribute_setup' and
  1989 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  1990 existing code accordingly, or use plain 'setup' together with old
  1991 Method.add_method.
  1992 
  1993 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  1994 to 'a -> thm, while results are always tagged with an authentic oracle
  1995 name.  The Isar command 'oracle' is now polymorphic, no argument type
  1996 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  1997 accordingly.  Note that extra performance may be gained by producing
  1998 the cterm carefully, avoiding slow Thm.cterm_of.
  1999 
  2000 * Simplified interface for defining document antiquotations via
  2001 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2002 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2003 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2004 examples.
  2005 
  2006 * More systematic treatment of long names, abstract name bindings, and
  2007 name space operations.  Basic operations on qualified names have been
  2008 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2009 Long_Name.append.  Old type bstring has been mostly replaced by
  2010 abstract type binding (see structure Binding), which supports precise
  2011 qualification by packages and local theory targets, as well as proper
  2012 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2013 bstring values into Binding.name, or better pass through abstract
  2014 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2015 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2016 
  2017 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2018 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2019 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2020 
  2021 * Disposed old type and term read functions (Sign.read_def_typ,
  2022 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2023 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2024 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2025 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2026 resort for legacy applications.
  2027 
  2028 * Disposed old declarations, tactics, tactic combinators that refer to
  2029 the simpset or claset of an implicit theory (such as Addsimps,
  2030 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2031 embedded ML text, or local_simpset_of with a proper context passed as
  2032 explicit runtime argument.
  2033 
  2034 * Rules and tactics that read instantiations (read_instantiate,
  2035 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2036 context, which is required for parsing and type-checking.  Moreover,
  2037 the variables are specified as plain indexnames, not string encodings
  2038 thereof.  INCOMPATIBILITY.
  2039 
  2040 * Generic Toplevel.add_hook interface allows to analyze the result of
  2041 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2042 for theorem dependency output of transactions resulting in a new
  2043 theory state.
  2044 
  2045 * ML antiquotations: block-structured compilation context indicated by
  2046 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2047 
  2048   @{binding name}                         - basic name binding
  2049   @{let ?pat = term}                      - term abbreviation (HO matching)
  2050   @{note name = fact}                     - fact abbreviation
  2051   @{thm fact}                             - singleton fact (with attributes)
  2052   @{thms fact}                            - general fact (with attributes)
  2053   @{lemma prop by method}                 - singleton goal
  2054   @{lemma prop by meth1 meth2}            - singleton goal
  2055   @{lemma prop1 ... propN by method}      - general goal
  2056   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2057   @{lemma (open) ...}                     - open derivation
  2058 
  2059 
  2060 *** System ***
  2061 
  2062 * The Isabelle "emacs" tool provides a specific interface to invoke
  2063 Proof General / Emacs, with more explicit failure if that is not
  2064 installed (the old isabelle-interface script silently falls back on
  2065 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2066 installation location of the Proof General distribution.
  2067 
  2068 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2069 the Isabelle process into a JVM/Scala application.  See
  2070 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2071 process wrapper has been discontinued.)
  2072 
  2073 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2074 
  2075 * Various status messages (with exact source position information) are
  2076 emitted, if proper markup print mode is enabled.  This allows
  2077 user-interface components to provide detailed feedback on internal
  2078 prover operations.
  2079 
  2080 
  2081 
  2082 New in Isabelle2008 (June 2008)
  2083 -------------------------------
  2084 
  2085 *** General ***
  2086 
  2087 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2088 and updated, with formally checked references as hyperlinks.
  2089 
  2090 * Theory loader: use_thy (and similar operations) no longer set the
  2091 implicit ML context, which was occasionally hard to predict and in
  2092 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2093 provides a proper context already.
  2094 
  2095 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2096 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2097 'use' within a theory file will do the job.
  2098 
  2099 * Name space merge now observes canonical order, i.e. the second space
  2100 is inserted into the first one, while existing entries in the first
  2101 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2102 swap theory imports.
  2103 
  2104 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2105 INCOMPATIBILITY in identifier syntax etc.
  2106 
  2107 * Outer syntax: string tokens no longer admit escaped white space,
  2108 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2109 white space without escapes.
  2110 
  2111 * Outer syntax: string tokens may contain arbitrary character codes
  2112 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2113 "foo_bar".
  2114 
  2115 
  2116 *** Pure ***
  2117 
  2118 * Context-dependent token translations.  Default setup reverts locally
  2119 fixed variables, and adds hilite markup for undeclared frees.
  2120 
  2121 * Unused theorems can be found using the new command 'unused_thms'.
  2122 There are three ways of invoking it:
  2123 
  2124 (1) unused_thms
  2125      Only finds unused theorems in the current theory.
  2126 
  2127 (2) unused_thms thy_1 ... thy_n -
  2128      Finds unused theorems in the current theory and all of its ancestors,
  2129      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2130 
  2131 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2132      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2133      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2134      their ancestors.
  2135 
  2136 In order to increase the readability of the list produced by
  2137 unused_thms, theorems that have been created by a particular instance
  2138 of a theory command such as 'inductive' or 'function' are considered
  2139 to belong to the same "group", meaning that if at least one theorem in
  2140 this group is used, the other theorems in the same group are no longer
  2141 reported as unused.  Moreover, if all theorems in the group are
  2142 unused, only one theorem in the group is displayed.
  2143 
  2144 Note that proof objects have to be switched on in order for
  2145 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2146 usually the case when using Proof General with the default settings).
  2147 
  2148 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2149 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2150 duplicate fact bindings, or even accidental fact duplications.  Note
  2151 that tools may maintain dynamically scoped facts systematically, using
  2152 PureThy.add_thms_dynamic.
  2153 
  2154 * Command 'hide' now allows to hide from "fact" name space as well.
  2155 
  2156 * Eliminated destructive theorem database, simpset, claset, and
  2157 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2158 update of theories within ML code.
  2159 
  2160 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2161 INCOMPATIBILITY, object-logics depending on former Pure require
  2162 additional setup PureThy.old_appl_syntax_setup; object-logics
  2163 depending on former CPure need to refer to Pure.
  2164 
  2165 * Commands 'use' and 'ML' are now purely functional, operating on
  2166 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2167 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2168 INCOMPATIBILITY.
  2169 
  2170 * Command 'setup': discontinued implicit version with ML reference.
  2171 
  2172 * Instantiation target allows for simultaneous specification of class
  2173 instance operations together with an instantiation proof.
  2174 Type-checking phase allows to refer to class operations uniformly.
  2175 See src/HOL/Complex/Complex.thy for an Isar example and
  2176 src/HOL/Library/Eval.thy for an ML example.
  2177 
  2178 * Indexing of literal facts: be more serious about including only
  2179 facts from the visible specification/proof context, but not the
  2180 background context (locale etc.).  Affects `prop` notation and method
  2181 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2182 situations.
  2183 
  2184 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2185 "(open)" option, which used to expose internal bound variables to the
  2186 proof text.
  2187 
  2188 * Isar statements: removed obsolete case "rule_context".
  2189 INCOMPATIBILITY, better use explicit fixes/assumes.
  2190 
  2191 * Locale proofs: default proof step now includes 'unfold_locales';
  2192 hence 'proof' without argument may be used to unfold locale
  2193 predicates.
  2194 
  2195 
  2196 *** Document preparation ***
  2197 
  2198 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2199 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2200 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2201 spot); renamed link color from "darkblue" to "linkcolor" (default
  2202 value unchanged, can be redefined via \definecolor); no longer sets
  2203 "a4paper" option (unnecessary or even intrusive).
  2204 
  2205 * Antiquotation @{lemma A method} proves proposition A by the given
  2206 method (either a method name or a method name plus (optional) method
  2207 arguments in parentheses) and prints A just like @{prop A}.
  2208 
  2209 
  2210 *** HOL ***
  2211 
  2212 * New primrec package.  Specification syntax conforms in style to
  2213 definition/function/....  No separate induction rule is provided.  The
  2214 "primrec" command distinguishes old-style and new-style specifications
  2215 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2216 When adjusting theories, beware: constants stemming from new-style
  2217 primrec specifications have authentic syntax.
  2218 
  2219 * Metis prover is now an order of magnitude faster, and also works
  2220 with multithreading.
  2221 
  2222 * Metis: the maximum number of clauses that can be produced from a
  2223 theorem is now given by the attribute max_clauses.  Theorems that
  2224 exceed this number are ignored, with a warning printed.
  2225 
  2226 * Sledgehammer no longer produces structured proofs by default. To
  2227 enable, declare [[sledgehammer_full = true]].  Attributes
  2228 reconstruction_modulus, reconstruction_sorts renamed
  2229 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2230 
  2231 * Method "induct_scheme" derives user-specified induction rules
  2232 from well-founded induction and completeness of patterns. This factors
  2233 out some operations that are done internally by the function package
  2234 and makes them available separately.  See
  2235 src/HOL/ex/Induction_Scheme.thy for examples.
  2236 
  2237 * More flexible generation of measure functions for termination
  2238 proofs: Measure functions can be declared by proving a rule of the
  2239 form "is_measure f" and giving it the [measure_function] attribute.
  2240 The "is_measure" predicate is logically meaningless (always true), and
  2241 just guides the heuristic.  To find suitable measure functions, the
  2242 termination prover sets up the goal "is_measure ?f" of the appropriate
  2243 type and generates all solutions by prolog-style backwards proof using
  2244 the declared rules.
  2245 
  2246 This setup also deals with rules like 
  2247 
  2248   "is_measure f ==> is_measure (list_size f)"
  2249 
  2250 which accommodates nested datatypes that recurse through lists.
  2251 Similar rules are predeclared for products and option types.
  2252 
  2253 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2254 
  2255   INCOMPATIBILITIES:
  2256 
  2257   - Definitions of overloaded constants on sets have to be replaced by
  2258     definitions on => and bool.
  2259 
  2260   - Some definitions of overloaded operators on sets can now be proved
  2261     using the definitions of the operators on => and bool.  Therefore,
  2262     the following theorems have been renamed:
  2263 
  2264       subset_def   -> subset_eq
  2265       psubset_def  -> psubset_eq
  2266       set_diff_def -> set_diff_eq
  2267       Compl_def    -> Compl_eq
  2268       Sup_set_def  -> Sup_set_eq
  2269       Inf_set_def  -> Inf_set_eq
  2270       sup_set_def  -> sup_set_eq
  2271       inf_set_def  -> inf_set_eq
  2272 
  2273   - Due to the incompleteness of the HO unification algorithm, some
  2274     rules such as subst may require manual instantiation, if some of
  2275     the unknowns in the rule is a set.
  2276 
  2277   - Higher order unification and forward proofs:
  2278     The proof pattern
  2279 
  2280       have "P (S::'a set)" <...>
  2281       then have "EX S. P S" ..
  2282 
  2283     no longer works (due to the incompleteness of the HO unification
  2284     algorithm) and must be replaced by the pattern
  2285 
  2286       have "EX S. P S"
  2287       proof
  2288         show "P S" <...>
  2289       qed
  2290 
  2291   - Calculational reasoning with subst (or similar rules):
  2292     The proof pattern
  2293 
  2294       have "P (S::'a set)" <...>
  2295       also have "S = T" <...>
  2296       finally have "P T" .
  2297 
  2298     no longer works (for similar reasons as the previous example) and
  2299     must be replaced by something like
  2300 
  2301       have "P (S::'a set)" <...>
  2302       moreover have "S = T" <...>
  2303       ultimately have "P T" by simp
  2304 
  2305   - Tactics or packages written in ML code:
  2306     Code performing pattern matching on types via
  2307 
  2308       Type ("set", [T]) => ...
  2309 
  2310     must be rewritten. Moreover, functions like strip_type or
  2311     binder_types no longer return the right value when applied to a
  2312     type of the form
  2313 
  2314       T1 => ... => Tn => U => bool
  2315 
  2316     rather than
  2317 
  2318       T1 => ... => Tn => U set
  2319 
  2320 * Merged theories Wellfounded_Recursion, Accessible_Part and
  2321 Wellfounded_Relations to theory Wellfounded.
  2322 
  2323 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  2324 
  2325 * Class finite no longer treats UNIV as class parameter.  Use class
  2326 enum from theory Library/Enum instead to achieve a similar effect.
  2327 INCOMPATIBILITY.
  2328 
  2329 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  2330 and "Cons".  INCOMPATIBILITY.
  2331 
  2332 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  2333 Potential INCOMPATIBILITY.
  2334 
  2335 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  2336 injective_fst_snd removed, use split_eta and prod_eqI instead.
  2337 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  2338 
  2339 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  2340 the same name in theory Orderings:
  2341 
  2342   less_trans
  2343   less_linear
  2344   le_imp_less_or_eq
  2345   le_less_trans
  2346   less_le_trans
  2347   less_not_sym
  2348   less_asym
  2349 
  2350 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  2351 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  2352 and different variable names.
  2353 
  2354 * Library/Option_ord.thy: Canonical order on option type.
  2355 
  2356 * Library/RBT.thy: Red-black trees, an efficient implementation of
  2357 finite maps.
  2358 
  2359 * Library/Countable.thy: Type class for countable types.
  2360 
  2361 * Theory Int: The representation of numerals has changed.  The infix
  2362 operator BIT and the bit datatype with constructors B0 and B1 have
  2363 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  2364 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  2365 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  2366 accordingly.
  2367 
  2368 * Theory Nat: definition of <= and < on natural numbers no longer
  2369 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  2370 le_def and less_def have disappeared.  Consider lemmas not_less
  2371 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  2372 
  2373 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  2374 (whose purpose mainly is for various fold_set functionals) have been
  2375 abandoned in favor of the existing algebraic classes
  2376 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  2377 lower_semilattice (resp. upper_semilattice) and linorder.
  2378 INCOMPATIBILITY.
  2379 
  2380 * Theory Transitive_Closure: induct and cases rules now declare proper
  2381 case_names ("base" and "step").  INCOMPATIBILITY.
  2382 
  2383 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  2384 lattices.  The form set-specific version is available as
  2385 Inductive.lfp_ordinal_induct_set.
  2386 
  2387 * Renamed theorems "power.simps" to "power_int.simps".
  2388 INCOMPATIBILITY.
  2389 
  2390 * Class semiring_div provides basic abstract properties of semirings
  2391 with division and modulo operations.  Subsumes former class dvd_mod.
  2392 
  2393 * Merged theories IntDef, Numeral and IntArith into unified theory
  2394 Int.  INCOMPATIBILITY.
  2395 
  2396 * Theory Library/Code_Index: type "index" now represents natural
  2397 numbers rather than integers.  INCOMPATIBILITY.
  2398 
  2399 * New class "uminus" with operation "uminus" (split of from class
  2400 "minus" which now only has operation "minus", binary).
  2401 INCOMPATIBILITY.
  2402 
  2403 * Constants "card", "internal_split", "option_map" now with authentic
  2404 syntax.  INCOMPATIBILITY.
  2405 
  2406 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  2407 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  2408 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  2409 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  2410 Sup_set_def, le_def, less_def, option_map_def now with object
  2411 equality.  INCOMPATIBILITY.
  2412 
  2413 * Records. Removed K_record, and replaced it by pure lambda term
  2414 %x. c. The simplifier setup is now more robust against eta expansion.
  2415 INCOMPATIBILITY: in cases explicitly referring to K_record.
  2416 
  2417 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  2418 
  2419 * Library/ListVector: new theory of arithmetic vector operations.
  2420 
  2421 * Library/Order_Relation: new theory of various orderings as sets of
  2422 pairs.  Defines preorders, partial orders, linear orders and
  2423 well-orders on sets and on types.
  2424 
  2425 
  2426 *** ZF ***
  2427 
  2428 * Renamed some theories to allow to loading both ZF and HOL in the
  2429 same session:
  2430 
  2431   Datatype  -> Datatype_ZF
  2432   Inductive -> Inductive_ZF
  2433   Int       -> Int_ZF
  2434   IntDiv    -> IntDiv_ZF
  2435   Nat       -> Nat_ZF
  2436   List      -> List_ZF
  2437   Main      -> Main_ZF
  2438 
  2439 INCOMPATIBILITY: ZF theories that import individual theories below
  2440 Main might need to be adapted.  Regular theory Main is still
  2441 available, as trivial extension of Main_ZF.
  2442 
  2443 
  2444 *** ML ***
  2445 
  2446 * ML within Isar: antiquotation @{const name} or @{const
  2447 name(typargs)} produces statically-checked Const term.
  2448 
  2449 * Functor NamedThmsFun: data is available to the user as dynamic fact
  2450 (of the same name).  Removed obsolete print command.
  2451 
  2452 * Removed obsolete "use_legacy_bindings" function.
  2453 
  2454 * The ``print mode'' is now a thread-local value derived from a global
  2455 template (the former print_mode reference), thus access becomes
  2456 non-critical.  The global print_mode reference is for session
  2457 management only; user-code should use print_mode_value,
  2458 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  2459 
  2460 * Functions system/system_out provide a robust way to invoke external
  2461 shell commands, with propagation of interrupts (requires Poly/ML
  2462 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  2463 
  2464 
  2465 *** System ***
  2466 
  2467 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  2468 in accordance with Proof General 3.7, which prefers GNU emacs.
  2469 
  2470 * isatool tty runs Isabelle process with plain tty interaction;
  2471 optional line editor may be specified via ISABELLE_LINE_EDITOR
  2472 setting, the default settings attempt to locate "ledit" and "rlwrap".
  2473 
  2474 * isatool browser now works with Cygwin as well, using general
  2475 "javapath" function defined in Isabelle process environment.
  2476 
  2477 * YXML notation provides a simple and efficient alternative to
  2478 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  2479 isatool yxml as described in the Isabelle system manual.
  2480 
  2481 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  2482 provides general wrapper for managing an Isabelle process in a robust
  2483 fashion, with ``cooked'' output from stdin/stderr.
  2484 
  2485 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  2486 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  2487 
  2488 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  2489 way of changing the user's settings is via
  2490 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  2491 script.
  2492 
  2493 * Multithreading.max_threads := 0 refers to the number of actual CPU
  2494 cores of the underlying machine, which is a good starting point for
  2495 optimal performance tuning.  The corresponding usedir option -M allows
  2496 "max" as an alias for "0".  WARNING: does not work on certain versions
  2497 of Mac OS (with Poly/ML 5.1).
  2498 
  2499 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  2500 adverse effect of Isabelle flooding interactive front-ends (notably
  2501 ProofGeneral / XEmacs).
  2502 
  2503 
  2504 
  2505 New in Isabelle2007 (November 2007)
  2506 -----------------------------------
  2507 
  2508 *** General ***
  2509 
  2510 * More uniform information about legacy features, notably a
  2511 warning/error of "Legacy feature: ...", depending on the state of the
  2512 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  2513 legacy features will disappear eventually.
  2514 
  2515 * Theory syntax: the header format ``theory A = B + C:'' has been
  2516 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  2517 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  2518 
  2519 * Theory syntax: the old non-Isar theory file format has been
  2520 discontinued altogether.  Note that ML proof scripts may still be used
  2521 with Isar theories; migration is usually quite simple with the ML
  2522 function use_legacy_bindings.  INCOMPATIBILITY.
  2523 
  2524 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  2525 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  2526 quotes.
  2527 
  2528 * Theory loader: be more serious about observing the static theory
  2529 header specifications (including optional directories), but not the
  2530 accidental file locations of previously successful loads.  The strict
  2531 update policy of former update_thy is now already performed by
  2532 use_thy, so the former has been removed; use_thys updates several
  2533 theories simultaneously, just as 'imports' within a theory header
  2534 specification, but without merging the results.  Potential
  2535 INCOMPATIBILITY: may need to refine theory headers and commands
  2536 ROOT.ML which depend on load order.
  2537 
  2538 * Theory loader: optional support for content-based file
  2539 identification, instead of the traditional scheme of full physical
  2540 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  2541 (cf. the system manual).  The new scheme allows to work with
  2542 non-finished theories in persistent session images, such that source
  2543 files may be moved later on without requiring reloads.
  2544 
  2545 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2546 file (with the same base name as the theory) are considered a legacy
  2547 feature, which will disappear eventually. Even now, the theory loader
  2548 no longer maintains dependencies on such files.
  2549 
  2550 * Syntax: the scope for resolving ambiguities via type-inference is
  2551 now limited to individual terms, instead of whole simultaneous
  2552 specifications as before. This greatly reduces the complexity of the
  2553 syntax module and improves flexibility by separating parsing and
  2554 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  2555 'fixes' etc.) are required in rare situations.
  2556 
  2557 * Syntax: constants introduced by new-style packages ('definition',
  2558 'abbreviation' etc.) are passed through the syntax module in
  2559 ``authentic mode''. This means that associated mixfix annotations
  2560 really stick to such constants, independently of potential name space
  2561 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  2562 trees are represented slightly differently, may need to adapt syntax
  2563 translations accordingly. Use CONST marker in 'translations' and
  2564 @{const_syntax} antiquotation in 'parse_translation' etc.
  2565 
  2566 * Legacy goal package: reduced interface to the bare minimum required
  2567 to keep existing proof scripts running.  Most other user-level
  2568 functions are now part of the OldGoals structure, which is *not* open
  2569 by default (consider isatool expandshort before open OldGoals).
  2570 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  2571 these tend to cause confusion about the actual goal (!) context being
  2572 used here, which is not necessarily the same as the_context().
  2573 
  2574 * Command 'find_theorems': supports "*" wild-card in "name:"
  2575 criterion; "with_dups" option.  Certain ProofGeneral versions might
  2576 support a specific search form (see ProofGeneral/CHANGES).
  2577 
  2578 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  2579 by default, which means that "prems" (and also "fixed variables") are
  2580 suppressed from proof state output.  Note that the ProofGeneral
  2581 settings mechanism allows to change and save options persistently, but
  2582 older versions of Isabelle will fail to start up if a negative prems
  2583 limit is imposed.
  2584 
  2585 * Local theory targets may be specified by non-nested blocks of
  2586 ``context/locale/class ... begin'' followed by ``end''.  The body may
  2587 contain definitions, theorems etc., including any derived mechanism
  2588 that has been implemented on top of these primitives.  This concept
  2589 generalizes the existing ``theorem (in ...)'' towards more versatility
  2590 and scalability.
  2591 
  2592 * Proof General interface: proper undo of final 'end' command;
  2593 discontinued Isabelle/classic mode (ML proof scripts).
  2594 
  2595 
  2596 *** Document preparation ***
  2597 
  2598 * Added antiquotation @{theory name} which prints the given name,
  2599 after checking that it refers to a valid ancestor theory in the
  2600 current context.
  2601 
  2602 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  2603 check the given source text as ML type/structure, printing verbatim.
  2604 
  2605 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  2606 "c args == rhs" given in the current context.  (Any number of
  2607 arguments may be given on the LHS.)
  2608 
  2609 
  2610 *** Pure ***
  2611 
  2612 * The 'class' package offers a combination of axclass and locale to
  2613 achieve Haskell-like type classes in Isabelle.  Definitions and
  2614 theorems within a class context produce both relative results (with
  2615 implicit parameters according to the locale context), and polymorphic
  2616 constants with qualified polymorphism (according to the class
  2617 context).  Within the body context of a 'class' target, a separate
  2618 syntax layer ("user space type system") takes care of converting
  2619 between global polymorphic consts and internal locale representation.
  2620 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  2621 "isatool doc classes" provides a tutorial.
  2622 
  2623 * Generic code generator framework allows to generate executable
  2624 code for ML and Haskell (including Isabelle classes).  A short usage
  2625 sketch:
  2626 
  2627     internal compilation:
  2628         export_code <list of constants (term syntax)> in SML
  2629     writing SML code to a file:
  2630         export_code <list of constants (term syntax)> in SML <filename>
  2631     writing OCaml code to a file:
  2632         export_code <list of constants (term syntax)> in OCaml <filename>
  2633     writing Haskell code to a bunch of files:
  2634         export_code <list of constants (term syntax)> in Haskell <filename>
  2635 
  2636     evaluating closed propositions to True/False using code generation:
  2637         method ``eval''
  2638 
  2639 Reasonable default setup of framework in HOL.
  2640 
  2641 Theorem attributs for selecting and transforming function equations theorems:
  2642 
  2643     [code fun]:        select a theorem as function equation for a specific constant
  2644     [code fun del]:    deselect a theorem as function equation for a specific constant
  2645     [code inline]:     select an equation theorem for unfolding (inlining) in place
  2646     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  2647 
  2648 User-defined serializations (target in {SML, OCaml, Haskell}):
  2649 
  2650     code_const <and-list of constants (term syntax)>
  2651       {(target) <and-list of const target syntax>}+
  2652 
  2653     code_type <and-list of type constructors>
  2654       {(target) <and-list of type target syntax>}+
  2655 
  2656     code_instance <and-list of instances>
  2657       {(target)}+
  2658         where instance ::= <type constructor> :: <class>
  2659 
  2660     code_class <and_list of classes>
  2661       {(target) <and-list of class target syntax>}+
  2662         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  2663 
  2664 code_instance and code_class only are effective to target Haskell.
  2665 
  2666 For example usage see src/HOL/ex/Codegenerator.thy and
  2667 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  2668 generation from Isabelle/HOL theories is available via "isatool doc
  2669 codegen".
  2670 
  2671 * Code generator: consts in 'consts_code' Isar commands are now
  2672 referred to by usual term syntax (including optional type
  2673 annotations).
  2674 
  2675 * Command 'no_translations' removes translation rules from theory
  2676 syntax.
  2677 
  2678 * Overloaded definitions are now actually checked for acyclic
  2679 dependencies.  The overloading scheme is slightly more general than
  2680 that of Haskell98, although Isabelle does not demand an exact
  2681 correspondence to type class and instance declarations.
  2682 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  2683 exotic versions of overloading -- at the discretion of the user!
  2684 
  2685 Polymorphic constants are represented via type arguments, i.e. the
  2686 instantiation that matches an instance against the most general
  2687 declaration given in the signature.  For example, with the declaration
  2688 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  2689 as c(nat).  Overloading is essentially simultaneous structural
  2690 recursion over such type arguments.  Incomplete specification patterns
  2691 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  2692 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  2693 Command 'print_theory' outputs the normalized system of recursive
  2694 equations, see section "definitions".
  2695 
  2696 * Configuration options are maintained within the theory or proof
  2697 context (with name and type bool/int/string), providing a very simple
  2698 interface to a poor-man's version of general context data.  Tools may
  2699 declare options in ML (e.g. using Attrib.config_int) and then refer to
  2700 these values using Config.get etc.  Users may change options via an
  2701 associated attribute of the same name.  This form of context
  2702 declaration works particularly well with commands 'declare' or
  2703 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  2704 very easy to avoid global references, which would not observe Isar
  2705 toplevel undo/redo and fail to work with multithreading.
  2706 
  2707 Various global ML references of Pure and HOL have been turned into
  2708 configuration options:
  2709 
  2710   Unify.search_bound		unify_search_bound
  2711   Unify.trace_bound		unify_trace_bound
  2712   Unify.trace_simp		unify_trace_simp
  2713   Unify.trace_types		unify_trace_types
  2714   Simplifier.simp_depth_limit	simp_depth_limit
  2715   Blast.depth_limit		blast_depth_limit
  2716   DatatypeProp.dtK		datatype_distinctness_limit
  2717   fast_arith_neq_limit  	fast_arith_neq_limit
  2718   fast_arith_split_limit	fast_arith_split_limit
  2719 
  2720 * Named collections of theorems may be easily installed as context
  2721 data using the functor NamedThmsFun (see also
  2722 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  2723 attributes; there is also a toplevel print command.  This facility is
  2724 just a common case of general context data, which is the preferred way
  2725 for anything more complex than just a list of facts in canonical
  2726 order.
  2727 
  2728 * Isar: command 'declaration' augments a local theory by generic
  2729 declaration functions written in ML.  This enables arbitrary content
  2730 being added to the context, depending on a morphism that tells the
  2731 difference of the original declaration context wrt. the application
  2732 context encountered later on.
  2733 
  2734 * Isar: proper interfaces for simplification procedures.  Command
  2735 'simproc_setup' declares named simprocs (with match patterns, and body
  2736 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  2737 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  2738 
  2739 * Isar: an extra pair of brackets around attribute declarations
  2740 abbreviates a theorem reference involving an internal dummy fact,
  2741 which will be ignored later --- only the effect of the attribute on
  2742 the background context will persist.  This form of in-place
  2743 declarations is particularly useful with commands like 'declare' and
  2744 'using', for example ``have A using [[simproc a]] by simp''.
  2745 
  2746 * Isar: method "assumption" (and implicit closing of subproofs) now
  2747 takes simple non-atomic goal assumptions into account: after applying
  2748 an assumption as a rule the resulting subgoals are solved by atomic
  2749 assumption steps.  This is particularly useful to finish 'obtain'
  2750 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  2751 without referring to the original premise "!!x. P x ==> thesis" in the
  2752 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  2753 more permissive.
  2754 
  2755 * Isar: implicit use of prems from the Isar proof context is
  2756 considered a legacy feature.  Common applications like ``have A .''
  2757 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  2758 referencing facts explicitly here improves readability and
  2759 maintainability of proof texts.
  2760 
  2761 * Isar: improper proof element 'guess' is like 'obtain', but derives
  2762 the obtained context from the course of reasoning!  For example:
  2763 
  2764   assume "EX x y. A x & B y"   -- "any previous fact"
  2765   then guess x and y by clarify
  2766 
  2767 This technique is potentially adventurous, depending on the facts and
  2768 proof tools being involved here.
  2769 
  2770 * Isar: known facts from the proof context may be specified as literal
  2771 propositions, using ASCII back-quote syntax.  This works wherever
  2772 named facts used to be allowed so far, in proof commands, proof
  2773 methods, attributes etc.  Literal facts are retrieved from the context
  2774 according to unification of type and term parameters.  For example,
  2775 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  2776 theorems in the current context, then these are valid literal facts:
  2777 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  2778 
  2779 There is also a proof method "fact" which does the same composition
  2780 for explicit goal states, e.g. the following proof texts coincide with
  2781 certain special cases of literal facts:
  2782 
  2783   have "A" by fact                 ==  note `A`
  2784   have "A ==> B" by fact           ==  note `A ==> B`
  2785   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  2786   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  2787 
  2788 * Isar: ":" (colon) is no longer a symbolic identifier character in
  2789 outer syntax.  Thus symbolic identifiers may be used without
  2790 additional white space in declarations like this: ``assume *: A''.
  2791 
  2792 * Isar: 'print_facts' prints all local facts of the current context,
  2793 both named and unnamed ones.
  2794 
  2795 * Isar: 'def' now admits simultaneous definitions, e.g.:
  2796 
  2797   def x == "t" and y == "u"
  2798 
  2799 * Isar: added command 'unfolding', which is structurally similar to
  2800 'using', but affects both the goal state and facts by unfolding given
  2801 rewrite rules.  Thus many occurrences of the 'unfold' method or
  2802 'unfolded' attribute may be replaced by first-class proof text.
  2803 
  2804 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  2805 and command 'unfolding' now all support object-level equalities
  2806 (potentially conditional).  The underlying notion of rewrite rule is
  2807 analogous to the 'rule_format' attribute, but *not* that of the
  2808 Simplifier (which is usually more generous).
  2809 
  2810 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  2811 premises of a theorem by n. Useful in conjunction with drule.
  2812 
  2813 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  2814 method expression within a sandbox consisting of the first N
  2815 sub-goals, which need to exist.  For example, ``simp_all [3]''
  2816 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  2817 simplifies all new goals that emerge from applying rule foo to the
  2818 originally first one.
  2819 
  2820 * Isar: schematic goals are no longer restricted to higher-order
  2821 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  2822 expected.
  2823 
  2824 * Isar: the conclusion of a long theorem statement is now either
  2825 'shows' (a simultaneous conjunction, as before), or 'obtains'
  2826 (essentially a disjunction of cases with local parameters and
  2827 assumptions).  The latter allows to express general elimination rules
  2828 adequately; in this notation common elimination rules look like this:
  2829 
  2830   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  2831     assumes "EX x. P x"
  2832     obtains x where "P x"
  2833 
  2834   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  2835     assumes "A & B"
  2836     obtains A and B
  2837 
  2838   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  2839     assumes "A | B"
  2840     obtains
  2841       A
  2842     | B
  2843 
  2844 The subsequent classical rules even refer to the formal "thesis"
  2845 explicitly:
  2846 
  2847   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  2848     obtains "~ thesis"
  2849 
  2850   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  2851     obtains "thesis ==> something"
  2852 
  2853 The actual proof of an 'obtains' statement is analogous to that of the
  2854 Isar proof element 'obtain', only that there may be several cases.
  2855 Optional case names may be specified in parentheses; these will be
  2856 available both in the present proof and as annotations in the
  2857 resulting rule, for later use with the 'cases' method (cf. attribute
  2858 case_names).
  2859 
  2860 * Isar: the assumptions of a long theorem statement are available as
  2861 "assms" fact in the proof context.  This is more appropriate than the
  2862 (historical) "prems", which refers to all assumptions of the current
  2863 context, including those from the target locale, proof body etc.
  2864 
  2865 * Isar: 'print_statement' prints theorems from the current theory or
  2866 proof context in long statement form, according to the syntax of a
  2867 top-level lemma.
  2868 
  2869 * Isar: 'obtain' takes an optional case name for the local context
  2870 introduction rule (default "that").
  2871 
  2872 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  2873 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  2874 to occur.
  2875 
  2876 * Pure: syntax "CONST name" produces a fully internalized constant
  2877 according to the current context.  This is particularly useful for
  2878 syntax translations that should refer to internal constant
  2879 representations independently of name spaces.
  2880 
  2881 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  2882 instead of "FOO ". This allows multiple binder declarations to coexist
  2883 in the same context.  INCOMPATIBILITY.
  2884 
  2885 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  2886 primitive that also works in a locale context (both for constants and
  2887 fixed variables). Type declaration and internal syntactic representation
  2888 of given constants retrieved from the context. Likewise, the
  2889 'no_notation' command allows to remove given syntax annotations from the
  2890 current context.
  2891 
  2892 * Isar/locales: new derived specification elements 'axiomatization',
  2893 'definition', 'abbreviation', which support type-inference, admit
  2894 object-level specifications (equality, equivalence).  See also the
  2895 isar-ref manual.  Examples:
  2896 
  2897   axiomatization
  2898     eq  (infix "===" 50) where
  2899     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  2900 
  2901   definition "f x y = x + y + 1"
  2902   definition g where "g x = f x x"
  2903 
  2904   abbreviation
  2905     neq  (infix "=!=" 50) where
  2906     "x =!= y == ~ (x === y)"
  2907 
  2908 These specifications may be also used in a locale context.  Then the
  2909 constants being introduced depend on certain fixed parameters, and the
  2910 constant name is qualified by the locale base name.  An internal
  2911 abbreviation takes care for convenient input and output, making the
  2912 parameters implicit and using the original short name.  See also
  2913 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  2914 entities from a monomorphic theory.
  2915 
  2916 Presently, abbreviations are only available 'in' a target locale, but
  2917 not inherited by general import expressions.  Also note that
  2918 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  2919 'translations' in common applications.  The "no_abbrevs" print mode
  2920 prevents folding of abbreviations in term output.
  2921 
  2922 Concrete syntax is attached to specified constants in internal form,
  2923 independently of name spaces.  The parse tree representation is
  2924 slightly different -- use 'notation' instead of raw 'syntax', and
  2925 'translations' with explicit "CONST" markup to accommodate this.
  2926 
  2927 * Pure/Isar: unified syntax for new-style specification mechanisms
  2928 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  2929 full type inference and dummy patterns ("_").  For example:
  2930 
  2931   definition "K x _ = x"
  2932 
  2933   inductive conj for A B
  2934   where "A ==> B ==> conj A B"
  2935 
  2936 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  2937 the current context.  Print mode "no_abbrevs" prevents inversion of
  2938 abbreviations on output.
  2939 
  2940 * Isar/locales: improved parameter handling: use of locales "var" and
  2941 "struct" no longer necessary; - parameter renamings are no longer
  2942 required to be injective.  For example, this allows to define
  2943 endomorphisms as locale endom = homom mult mult h.
  2944 
  2945 * Isar/locales: changed the way locales with predicates are defined.
  2946 Instead of accumulating the specification, the imported expression is
  2947 now an interpretation.  INCOMPATIBILITY: different normal form of
  2948 locale expressions.  In particular, in interpretations of locales with
  2949 predicates, goals repesenting already interpreted fragments are not
  2950 removed automatically.  Use methods `intro_locales' and
  2951 `unfold_locales'; see below.
  2952 
  2953 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  2954 provide backward reasoning on locales predicates.  The methods are
  2955 aware of interpretations and discharge corresponding goals.
  2956 `intro_locales' is less aggressive then `unfold_locales' and does not
  2957 unfold predicates to assumptions.
  2958 
  2959 * Isar/locales: the order in which locale fragments are accumulated
  2960 has changed.  This enables to override declarations from fragments due
  2961 to interpretations -- for example, unwanted simp rules.
  2962 
  2963 * Isar/locales: interpretation in theories and proof contexts has been
  2964 extended.  One may now specify (and prove) equations, which are
  2965 unfolded in interpreted theorems.  This is useful for replacing
  2966 defined concepts (constants depending on locale parameters) by
  2967 concepts already existing in the target context.  Example:
  2968 
  2969   interpretation partial_order ["op <= :: [int, int] => bool"]
  2970     where "partial_order.less (op <=) (x::int) y = (x < y)"
  2971 
  2972 Typically, the constant `partial_order.less' is created by a
  2973 definition specification element in the context of locale
  2974 partial_order.
  2975 
  2976 * Method "induct": improved internal context management to support
  2977 local fixes and defines on-the-fly. Thus explicit meta-level
  2978 connectives !!  and ==> are rarely required anymore in inductive goals
  2979 (using object-logic connectives for this purpose has been long
  2980 obsolete anyway). Common proof patterns are explained in
  2981 src/HOL/Induct/Common_Patterns.thy, see also
  2982 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  2983 examples.
  2984 
  2985 * Method "induct": improved handling of simultaneous goals. Instead of
  2986 introducing object-level conjunction, the statement is now split into
  2987 several conclusions, while the corresponding symbolic cases are nested
  2988 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  2989 see src/HOL/Induct/Common_Patterns.thy, for example.
  2990 
  2991 * Method "induct": mutual induction rules are now specified as a list
  2992 of rule sharing the same induction cases. HOL packages usually provide
  2993 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  2994 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  2995 mutual induction rules differently, i.e. like this:
  2996 
  2997   (induct rule: foo_bar.inducts)
  2998   (induct set: foo bar)
  2999   (induct pred: foo bar)
  3000   (induct type: foo bar)
  3001 
  3002 The ML function ProjectRule.projections turns old-style rules into the
  3003 new format.
  3004 
  3005 * Method "coinduct": dual of induction, see
  3006 src/HOL/Library/Coinductive_List.thy for various examples.
  3007 
  3008 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3009 considered a legacy feature.
  3010 
  3011 * Attribute "symmetric" produces result with standardized schematic
  3012 variables (index 0).  Potential INCOMPATIBILITY.
  3013 
  3014 * Simplifier: by default the simplifier trace only shows top level
  3015 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3016 default. Thus there is less danger of being flooded by the trace. The
  3017 trace indicates where parts have been suppressed.
  3018   
  3019 * Provers/classical: removed obsolete classical version of elim_format
  3020 attribute; classical elim/dest rules are now treated uniformly when
  3021 manipulating the claset.
  3022 
  3023 * Provers/classical: stricter checks to ensure that supplied intro,
  3024 dest and elim rules are well-formed; dest and elim rules must have at
  3025 least one premise.
  3026 
  3027 * Provers/classical: attributes dest/elim/intro take an optional
  3028 weight argument for the rule (just as the Pure versions).  Weights are
  3029 ignored by automated tools, but determine the search order of single
  3030 rule steps.
  3031 
  3032 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3033 where the body does not mention the bound variable.  Note that dummy
  3034 patterns implicitly depend on their context of bounds, which makes
  3035 "{_. _}" match any set comprehension as expected.  Potential
  3036 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3037 constant "_idtdummy" in the binding position.
  3038 
  3039 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3040 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3041 for example "A -> B" => "Pi A (%_. B)".
  3042 
  3043 * Pure: 'class_deps' command visualizes the subclass relation, using
  3044 the graph browser tool.
  3045 
  3046 * Pure: 'print_theory' now suppresses certain internal declarations by
  3047 default; use '!' option for full details.
  3048 
  3049 
  3050 *** HOL ***
  3051 
  3052 * Method "metis" proves goals by applying the Metis general-purpose
  3053 resolution prover (see also http://gilith.com/software/metis/).
  3054 Examples are in the directory MetisExamples.  WARNING: the
  3055 Isabelle/HOL-Metis integration does not yet work properly with
  3056 multi-threading.
  3057   
  3058 * Command 'sledgehammer' invokes external automatic theorem provers as
  3059 background processes.  It generates calls to the "metis" method if
  3060 successful. These can be pasted into the proof.  Users do not have to
  3061 wait for the automatic provers to return.  WARNING: does not really
  3062 work with multi-threading.
  3063 
  3064 * New "auto_quickcheck" feature tests outermost goal statements for
  3065 potential counter-examples.  Controlled by ML references
  3066 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3067 5000 milliseconds).  Fails silently if statements is outside of
  3068 executable fragment, or any other codgenerator problem occurs.
  3069 
  3070 * New constant "undefined" with axiom "undefined x = undefined".
  3071 
  3072 * Added class "HOL.eq", allowing for code generation with polymorphic
  3073 equality.
  3074 
  3075 * Some renaming of class constants due to canonical name prefixing in
  3076 the new 'class' package:
  3077 
  3078     HOL.abs ~> HOL.abs_class.abs
  3079     HOL.divide ~> HOL.divide_class.divide
  3080     0 ~> HOL.zero_class.zero
  3081     1 ~> HOL.one_class.one
  3082     op + ~> HOL.plus_class.plus
  3083     op - ~> HOL.minus_class.minus
  3084     uminus ~> HOL.minus_class.uminus
  3085     op * ~> HOL.times_class.times
  3086     op < ~> HOL.ord_class.less
  3087     op <= > HOL.ord_class.less_eq
  3088     Nat.power ~> Power.power_class.power
  3089     Nat.size ~> Nat.size_class.size
  3090     Numeral.number_of ~> Numeral.number_class.number_of
  3091     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3092     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3093     Orderings.min ~> Orderings.ord_class.min
  3094     Orderings.max ~> Orderings.ord_class.max
  3095     Divides.op div ~> Divides.div_class.div
  3096     Divides.op mod ~> Divides.div_class.mod
  3097     Divides.op dvd ~> Divides.div_class.dvd
  3098 
  3099 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3100 
  3101 a) User-defined constants using any of the names "plus", "minus",
  3102 "times", "less" or "less_eq". The standard syntax translations for
  3103 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3104 names.
  3105 
  3106 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3107 INCOMPATIBILITY: use more specific names.
  3108 
  3109 c) Permutative equations (e.g. "a + b = b + a")
  3110 Since the change of names also changes the order of terms, permutative
  3111 rewrite rules may get applied in a different order. Experience shows
  3112 that this is rarely the case (only two adaptions in the whole Isabelle
  3113 distribution).  INCOMPATIBILITY: rewrite proofs
  3114 
  3115 d) ML code directly refering to constant names
  3116 This in general only affects hand-written proof tactics, simprocs and
  3117 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3118 Consider using @{const_name} antiquotation.
  3119 
  3120 * New class "default" with associated constant "default".
  3121 
  3122 * Function "sgn" is now overloaded and available on int, real, complex
  3123 (and other numeric types), using class "sgn".  Two possible defs of
  3124 sgn are given as equational assumptions in the classes sgn_if and
  3125 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3126 INCOMPATIBILITY.
  3127 
  3128 * Locale "partial_order" now unified with class "order" (cf. theory
  3129 Orderings), added parameter "less".  INCOMPATIBILITY.
  3130 
  3131 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3132 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3133 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3134 
  3135 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3136 changed order of proof goals in instance proofs.
  3137 
  3138 * The transitivity reasoner for partial and linear orders is set up
  3139 for classes "order" and "linorder".  Instances of the reasoner are available
  3140 in all contexts importing or interpreting the corresponding locales.
  3141 Method "order" invokes the reasoner separately; the reasoner
  3142 is also integrated with the Simplifier as a solver.  Diagnostic
  3143 command 'print_orders' shows the available instances of the reasoner
  3144 in the current context.
  3145 
  3146 * Localized monotonicity predicate in theory "Orderings"; integrated
  3147 lemmas max_of_mono and min_of_mono with this predicate.
  3148 INCOMPATIBILITY.
  3149 
  3150 * Formulation of theorem "dense" changed slightly due to integration
  3151 with new class dense_linear_order.
  3152 
  3153 * Uniform lattice theory development in HOL.
  3154 
  3155     constants "meet" and "join" now named "inf" and "sup"
  3156     constant "Meet" now named "Inf"
  3157 
  3158     classes "meet_semilorder" and "join_semilorder" now named
  3159       "lower_semilattice" and "upper_semilattice"
  3160     class "lorder" now named "lattice"
  3161     class "comp_lat" now named "complete_lattice"
  3162 
  3163     Instantiation of lattice classes allows explicit definitions
  3164     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3165 
  3166   INCOMPATIBILITY.  Theorem renames:
  3167 
  3168     meet_left_le            ~> inf_le1
  3169     meet_right_le           ~> inf_le2
  3170     join_left_le            ~> sup_ge1
  3171     join_right_le           ~> sup_ge2
  3172     meet_join_le            ~> inf_sup_ord
  3173     le_meetI                ~> le_infI
  3174     join_leI                ~> le_supI
  3175     le_meet                 ~> le_inf_iff
  3176     le_join                 ~> ge_sup_conv
  3177     meet_idempotent         ~> inf_idem
  3178     join_idempotent         ~> sup_idem
  3179     meet_comm               ~> inf_commute
  3180     join_comm               ~> sup_commute
  3181     meet_leI1               ~> le_infI1
  3182     meet_leI2               ~> le_infI2
  3183     le_joinI1               ~> le_supI1
  3184     le_joinI2               ~> le_supI2
  3185     meet_assoc              ~> inf_assoc
  3186     join_assoc              ~> sup_assoc
  3187     meet_left_comm          ~> inf_left_commute
  3188     meet_left_idempotent    ~> inf_left_idem
  3189     join_left_comm          ~> sup_left_commute
  3190     join_left_idempotent    ~> sup_left_idem
  3191     meet_aci                ~> inf_aci
  3192     join_aci                ~> sup_aci
  3193     le_def_meet             ~> le_iff_inf
  3194     le_def_join             ~> le_iff_sup
  3195     join_absorp2            ~> sup_absorb2
  3196     join_absorp1            ~> sup_absorb1
  3197     meet_absorp1            ~> inf_absorb1
  3198     meet_absorp2            ~> inf_absorb2
  3199     meet_join_absorp        ~> inf_sup_absorb
  3200     join_meet_absorp        ~> sup_inf_absorb
  3201     distrib_join_le         ~> distrib_sup_le
  3202     distrib_meet_le         ~> distrib_inf_le
  3203 
  3204     add_meet_distrib_left   ~> add_inf_distrib_left
  3205     add_join_distrib_left   ~> add_sup_distrib_left
  3206     is_join_neg_meet        ~> is_join_neg_inf
  3207     is_meet_neg_join        ~> is_meet_neg_sup
  3208     add_meet_distrib_right  ~> add_inf_distrib_right
  3209     add_join_distrib_right  ~> add_sup_distrib_right
  3210     add_meet_join_distribs  ~> add_sup_inf_distribs
  3211     join_eq_neg_meet        ~> sup_eq_neg_inf
  3212     meet_eq_neg_join        ~> inf_eq_neg_sup
  3213     add_eq_meet_join        ~> add_eq_inf_sup
  3214     meet_0_imp_0            ~> inf_0_imp_0
  3215     join_0_imp_0            ~> sup_0_imp_0
  3216     meet_0_eq_0             ~> inf_0_eq_0
  3217     join_0_eq_0             ~> sup_0_eq_0
  3218     neg_meet_eq_join        ~> neg_inf_eq_sup
  3219     neg_join_eq_meet        ~> neg_sup_eq_inf
  3220     join_eq_if              ~> sup_eq_if
  3221 
  3222     mono_meet               ~> mono_inf
  3223     mono_join               ~> mono_sup
  3224     meet_bool_eq            ~> inf_bool_eq
  3225     join_bool_eq            ~> sup_bool_eq
  3226     meet_fun_eq             ~> inf_fun_eq
  3227     join_fun_eq             ~> sup_fun_eq
  3228     meet_set_eq             ~> inf_set_eq
  3229     join_set_eq             ~> sup_set_eq
  3230     meet1_iff               ~> inf1_iff
  3231     meet2_iff               ~> inf2_iff
  3232     meet1I                  ~> inf1I
  3233     meet2I                  ~> inf2I
  3234     meet1D1                 ~> inf1D1
  3235     meet2D1                 ~> inf2D1
  3236     meet1D2                 ~> inf1D2
  3237     meet2D2                 ~> inf2D2
  3238     meet1E                  ~> inf1E
  3239     meet2E                  ~> inf2E
  3240     join1_iff               ~> sup1_iff
  3241     join2_iff               ~> sup2_iff
  3242     join1I1                 ~> sup1I1
  3243     join2I1                 ~> sup2I1
  3244     join1I1                 ~> sup1I1
  3245     join2I2                 ~> sup1I2
  3246     join1CI                 ~> sup1CI
  3247     join2CI                 ~> sup2CI
  3248     join1E                  ~> sup1E
  3249     join2E                  ~> sup2E
  3250 
  3251     is_meet_Meet            ~> is_meet_Inf
  3252     Meet_bool_def           ~> Inf_bool_def
  3253     Meet_fun_def            ~> Inf_fun_def
  3254     Meet_greatest           ~> Inf_greatest
  3255     Meet_lower              ~> Inf_lower
  3256     Meet_set_def            ~> Inf_set_def
  3257 
  3258     Sup_def                 ~> Sup_Inf
  3259     Sup_bool_eq             ~> Sup_bool_def
  3260     Sup_fun_eq              ~> Sup_fun_def
  3261     Sup_set_eq              ~> Sup_set_def
  3262 
  3263     listsp_meetI            ~> listsp_infI
  3264     listsp_meet_eq          ~> listsp_inf_eq
  3265 
  3266     meet_min                ~> inf_min
  3267     join_max                ~> sup_max
  3268 
  3269 * Added syntactic class "size"; overloaded constant "size" now has
  3270 type "'a::size ==> bool"
  3271 
  3272 * Internal reorganisation of `size' of datatypes: size theorems
  3273 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3274 simplification rules by default!); theorems "prod.size" now named
  3275 "*.size".
  3276 
  3277 * Class "div" now inherits from class "times" rather than "type".
  3278 INCOMPATIBILITY.
  3279 
  3280 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  3281 Linorder etc.  have disappeared; operations defined in terms of
  3282 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  3283 
  3284 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  3285 
  3286 * HOL-Word: New extensive library and type for generic, fixed size
  3287 machine words, with arithemtic, bit-wise, shifting and rotating
  3288 operations, reflection into int, nat, and bool lists, automation for
  3289 linear arithmetic (by automatic reflection into nat or int), including
  3290 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  3291 arithmetic type classes, supporting automatic simplification of
  3292 numerals on all operations.
  3293 
  3294 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  3295 
  3296 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  3297 
  3298 * Code generator library theories:
  3299   - Code_Integer represents HOL integers by big integer literals in target
  3300     languages.
  3301   - Code_Char represents HOL characters by character literals in target
  3302     languages.
  3303   - Code_Char_chr like Code_Char, but also offers treatment of character
  3304     codes; includes Code_Integer.
  3305   - Executable_Set allows to generate code for finite sets using lists.
  3306   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  3307     denominator).
  3308   - Executable_Real implements a subset of real numbers, namly those
  3309     representable by rational numbers.
  3310   - Efficient_Nat implements natural numbers by integers, which in general will
  3311     result in higher efficency; pattern matching with 0/Suc is eliminated;
  3312     includes Code_Integer.
  3313   - Code_Index provides an additional datatype index which is mapped to
  3314     target-language built-in integers.
  3315   - Code_Message provides an additional datatype message_string which is isomorphic to
  3316     strings; messages are mapped to target-language strings.
  3317 
  3318 * New package for inductive predicates
  3319 
  3320   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  3321 
  3322     inductive
  3323       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3324       for z_1 :: U_1 and ... and z_n :: U_m
  3325     where
  3326       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3327     | ...
  3328 
  3329   with full support for type-inference, rather than
  3330 
  3331     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3332 
  3333     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3334     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3335 
  3336     inductive "s z_1 ... z_m"
  3337     intros
  3338       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3339       ...
  3340 
  3341   For backward compatibility, there is a wrapper allowing inductive
  3342   sets to be defined with the new package via
  3343 
  3344     inductive_set
  3345       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3346       for z_1 :: U_1 and ... and z_n :: U_m
  3347     where
  3348       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3349     | ...
  3350 
  3351   or
  3352 
  3353     inductive_set
  3354       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3355       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3356       for z_1 :: U_1 and ... and z_n :: U_m
  3357     where
  3358       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3359     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3360     | ...
  3361 
  3362   if the additional syntax "p ..." is required.
  3363 
  3364   Numerous examples can be found in the subdirectories src/HOL/Auth,
  3365   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  3366 
  3367   INCOMPATIBILITIES:
  3368 
  3369   - Since declaration and definition of inductive sets or predicates
  3370     is no longer separated, abbreviations involving the newly
  3371     introduced sets or predicates must be specified together with the
  3372     introduction rules after the 'where' keyword (see above), rather
  3373     than before the actual inductive definition.
  3374 
  3375   - The variables in induction and elimination rules are now
  3376     quantified in the order of their occurrence in the introduction
  3377     rules, rather than in alphabetical order. Since this may break
  3378     some proofs, these proofs either have to be repaired, e.g. by
  3379     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  3380     statements of the form
  3381 
  3382       case (rule_i a_i_1 ... a_i_{k_i})
  3383 
  3384     or the old order of quantification has to be restored by explicitly adding
  3385     meta-level quantifiers in the introduction rules, i.e.
  3386 
  3387       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  3388 
  3389   - The format of the elimination rules is now
  3390 
  3391       p z_1 ... z_m x_1 ... x_n ==>
  3392         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3393         ==> ... ==> P
  3394 
  3395     for predicates and
  3396 
  3397       (x_1, ..., x_n) : s z_1 ... z_m ==>
  3398         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3399         ==> ... ==> P
  3400 
  3401     for sets rather than
  3402 
  3403       x : s z_1 ... z_m ==>
  3404         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  3405         ==> ... ==> P
  3406 
  3407     This may require terms in goals to be expanded to n-tuples
  3408     (e.g. using case_tac or simplification with the split_paired_all
  3409     rule) before the above elimination rule is applicable.
  3410 
  3411   - The elimination or case analysis rules for (mutually) inductive
  3412     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  3413     list of rules "p_1_..._p_k.elims" is no longer available.
  3414 
  3415 * New package "function"/"fun" for general recursive functions,
  3416 supporting mutual and nested recursion, definitions in local contexts,
  3417 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  3418 for small examples, and the separate tutorial on the function
  3419 package. The old recdef "package" is still available as before, but
  3420 users are encouraged to use the new package.
  3421 
  3422 * Method "lexicographic_order" automatically synthesizes termination
  3423 relations as lexicographic combinations of size measures. 
  3424 
  3425 * Case-expressions allow arbitrary constructor-patterns (including
  3426 "_") and take their order into account, like in functional
  3427 programming.  Internally, this is translated into nested
  3428 case-expressions; missing cases are added and mapped to the predefined
  3429 constant "undefined". In complicated cases printing may no longer show
  3430 the original input but the internal form. Lambda-abstractions allow
  3431 the same form of pattern matching: "% pat1 => e1 | ..." is an
  3432 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  3433 variable.
  3434 
  3435 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  3436 is an abbreviation for "of_nat :: nat => int". The simplification
  3437 rules for "of_nat" have been changed to work like "int" did
  3438 previously.  Potential INCOMPATIBILITY:
  3439   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  3440   - of_nat_diff and of_nat_mult are no longer default simp rules
  3441 
  3442 * Method "algebra" solves polynomial equations over (semi)rings using
  3443 Groebner bases. The (semi)ring structure is defined by locales and the
  3444 tool setup depends on that generic context. Installing the method for
  3445 a specific type involves instantiating the locale and possibly adding
  3446 declarations for computation on the coefficients.  The method is
  3447 already instantiated for natural numbers and for the axiomatic class
  3448 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  3449 CALCULEMUS 2007 for the general principles underlying this
  3450 architecture of context-aware proof-tools.
  3451 
  3452 * Method "ferrack" implements quantifier elimination over
  3453 special-purpose dense linear orders using locales (analogous to
  3454 "algebra"). The method is already installed for class
  3455 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  3456 rat, etc.
  3457 
  3458 * Former constant "List.op @" now named "List.append".  Use ML
  3459 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  3460 circumvent possible incompatibilities when working on ML level.
  3461 
  3462 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  3463 
  3464 * New function listsum :: 'a list => 'a for arbitrary monoids.
  3465 Special syntax: "SUM x <- xs. f x" (and latex variants)
  3466 
  3467 * New syntax for Haskell-like list comprehension (input only), eg.
  3468 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  3469 
  3470 * The special syntax for function "filter" has changed from [x :
  3471 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  3472 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  3473 
  3474 * [a..b] is now defined for arbitrary linear orders.  It used to be
  3475 defined on nat only, as an abbreviation for [a..<Suc b]
  3476 INCOMPATIBILITY.
  3477 
  3478 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  3479 
  3480 * New functions "sorted" and "sort" in src/HOL/List.thy.
  3481 
  3482 * New lemma collection field_simps (an extension of ring_simps) for
  3483 manipulating (in)equations involving division. Multiplies with all
  3484 denominators that can be proved to be non-zero (in equations) or
  3485 positive/negative (in inequations).
  3486 
  3487 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  3488 have been improved and renamed to ring_simps, group_simps and
  3489 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  3490 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  3491 
  3492 * Theory Library/Commutative_Ring: switched from recdef to function
  3493 package; constants add, mul, pow now curried.  Infix syntax for
  3494 algebraic operations.
  3495 
  3496 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  3497 INCOMPATIBILITY.
  3498 
  3499 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  3500 INCOMPATIBILITY.
  3501 
  3502 * HOL/records: generalised field-update to take a function on the
  3503 field rather than the new value: r(|A := x|) is translated to A_update
  3504 (K x) r The K-combinator that is internally used is called K_record.
  3505 INCOMPATIBILITY: Usage of the plain update functions has to be
  3506 adapted.
  3507  
  3508 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  3509 * x = 0, which are required for a semiring.  Richer structures do not
  3510 inherit from semiring_0 anymore, because this property is a theorem
  3511 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  3512 there is more to prove, but this is mostly trivial.
  3513 
  3514 * Class "recpower" is generalized to arbitrary monoids, not just
  3515 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  3516 commutativity or semiring properties additionally.
  3517 
  3518 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  3519 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  3520 better use 'abbreviation'.
  3521 
  3522 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  3523 
  3524 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  3525 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  3526 significant changes for setting up numeral syntax for types:
  3527   - New constants Numeral.pred and Numeral.succ instead
  3528       of former Numeral.bin_pred and Numeral.bin_succ.
  3529   - Use integer operations instead of bin_add, bin_mult and so on.
  3530   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  3531   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  3532 
  3533 See src/HOL/Integ/IntArith.thy for an example setup.
  3534 
  3535 * Command 'normal_form' computes the normal form of a term that may
  3536 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  3537 produces ``[b, c, a]'' (without proof).  This command is suitable for
  3538 heavy-duty computations because the functions are compiled to ML
  3539 first.  Correspondingly, a method "normalization" is provided.  See
  3540 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  3541 
  3542 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  3543 25 like -->); output depends on the "iff" print_mode, the default is
  3544 "A = B" (with priority 50).
  3545 
  3546 * Relations less (<) and less_eq (<=) are also available on type bool.
  3547 Modified syntax to disallow nesting without explicit parentheses,
  3548 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  3549 INCOMPATIBILITY.
  3550 
  3551 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  3552 
  3553 * Relation composition operator "op O" now has precedence 75 and binds
  3554 stronger than union and intersection. INCOMPATIBILITY.
  3555 
  3556 * The old set interval syntax "{m..n(}" (and relatives) has been
  3557 removed.  Use "{m..<n}" (and relatives) instead.
  3558 
  3559 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  3560 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  3561 ``declare [[simproc del: neq]]''.
  3562 
  3563 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  3564 True/False.
  3565 
  3566 * Theorem Cons_eq_map_conv no longer declared as "simp".
  3567 
  3568 * Theorem setsum_mult renamed to setsum_right_distrib.
  3569 
  3570 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  3571 ``rule'' method.
  3572 
  3573 * Reimplemented methods "sat" and "satx", with several improvements:
  3574 goals no longer need to be stated as "<prems> ==> False", equivalences
  3575 (i.e. "=" on type bool) are handled, variable names of the form
  3576 "lit_<n>" are no longer reserved, significant speedup.
  3577 
  3578 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  3579 zChaff is still supported as well.
  3580 
  3581 * 'inductive' and 'datatype': provide projections of mutual rules,
  3582 bundled as foo_bar.inducts;
  3583 
  3584 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  3585 Library.
  3586 
  3587 * Library: moved theory Accessible_Part to main HOL.
  3588 
  3589 * Library: added theory Coinductive_List of potentially infinite lists
  3590 as greatest fixed-point.
  3591 
  3592 * Library: added theory AssocList which implements (finite) maps as
  3593 association lists.
  3594 
  3595 * Method "evaluation" solves goals (i.e. a boolean expression)
  3596 efficiently by compiling it to ML.  The goal is "proved" (via an
  3597 oracle) if it evaluates to True.
  3598 
  3599 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  3600 also when invoked by the simplifier.  This results in the Simplifier
  3601 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  3602 Configuration option fast_arith_split_limit=0 recovers the old
  3603 behavior.
  3604 
  3605 * Support for hex (0x20) and binary (0b1001) numerals.
  3606 
  3607 * New method: reify eqs (t), where eqs are equations for an
  3608 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  3609 parameter, computes a term s::'b and a list xs::'a list and proves the
  3610 theorem I xs s = t. This is also known as reification or quoting. The
  3611 resulting theorem is applied to the subgoal to substitute t with I xs
  3612 s.  If t is omitted, the subgoal itself is reified.
  3613 
  3614 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  3615 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  3616 where f is supposed to be a computable function (in the sense of code
  3617 generattion). The method uses reify to compute s and xs as above then
  3618 applies corr_thm and uses normalization by evaluation to "prove" f s =
  3619 r and finally gets the theorem t = r, which is again applied to the
  3620 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  3621 
  3622 * Reflection: Automatic reification now handels binding, an example is
  3623 available in src/HOL/ex/ReflectionEx.thy
  3624 
  3625 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  3626 command 'statespace' that is similar to 'record', but introduces an
  3627 abstract specification based on the locale infrastructure instead of
  3628 HOL types.  This leads to extra flexibility in composing state spaces,
  3629 in particular multiple inheritance and renaming of components.
  3630 
  3631 
  3632 *** HOL-Complex ***
  3633 
  3634 * Hyperreal: Functions root and sqrt are now defined on negative real
  3635 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  3636 Nonnegativity side conditions have been removed from many lemmas, so
  3637 that more subgoals may now be solved by simplification; potential
  3638 INCOMPATIBILITY.
  3639 
  3640 * Real: new type classes formalize real normed vector spaces and
  3641 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  3642 and norm :: 'a => real.
  3643 
  3644 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  3645 reals into other types. The overloaded constant Reals :: 'a set is now
  3646 defined as range of_real; potential INCOMPATIBILITY.
  3647 
  3648 * Real: proper support for ML code generation, including 'quickcheck'.
  3649 Reals are implemented as arbitrary precision rationals.
  3650 
  3651 * Hyperreal: Several constants that previously worked only for the
  3652 reals have been generalized, so they now work over arbitrary vector
  3653 spaces. Type annotations may need to be added in some cases; potential
  3654 INCOMPATIBILITY.
  3655 
  3656   Infinitesimal  :: ('a::real_normed_vector) star set
  3657   HFinite        :: ('a::real_normed_vector) star set
  3658   HInfinite      :: ('a::real_normed_vector) star set
  3659   approx         :: ('a::real_normed_vector) star => 'a star => bool
  3660   monad          :: ('a::real_normed_vector) star => 'a star set
  3661   galaxy         :: ('a::real_normed_vector) star => 'a star set
  3662   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  3663   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  3664   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  3665   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  3666   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  3667   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  3668   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  3669   sgn            :: 'a::real_normed_vector => 'a
  3670   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  3671 
  3672 * Complex: Some complex-specific constants are now abbreviations for
  3673 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  3674 hnorm.  Other constants have been entirely removed in favor of the
  3675 polymorphic versions (INCOMPATIBILITY):
  3676 
  3677   approx        <-- capprox
  3678   HFinite       <-- CFinite
  3679   HInfinite     <-- CInfinite
  3680   Infinitesimal <-- CInfinitesimal
  3681   monad         <-- cmonad
  3682   galaxy        <-- cgalaxy
  3683   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  3684   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  3685   (ns)deriv     <-- (ns)cderiv
  3686 
  3687 
  3688 *** HOL-Algebra ***
  3689 
  3690 * Formalisation of ideals and the quotient construction over rings.
  3691 
  3692 * Order and lattice theory no longer based on records.
  3693 INCOMPATIBILITY.
  3694 
  3695 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  3696 greatest_closed.  INCOMPATIBILITY.
  3697 
  3698 * Method algebra is now set up via an attribute.  For examples see
  3699 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  3700 of algebraic structures.
  3701 
  3702 * Renamed theory CRing to Ring.
  3703 
  3704 
  3705 *** HOL-Nominal ***
  3706 
  3707 * Substantial, yet incomplete support for nominal datatypes (binding
  3708 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  3709 src/HOL/Nominal/Examples.  Prospective users should consult
  3710 http://isabelle.in.tum.de/nominal/
  3711 
  3712 
  3713 *** ML ***
  3714 
  3715 * ML basics: just one true type int, which coincides with IntInf.int
  3716 (even on SML/NJ).
  3717 
  3718 * ML within Isar: antiquotations allow to embed statically-checked
  3719 formal entities in the source, referring to the context available at
  3720 compile-time.  For example:
  3721 
  3722 ML {* @{sort "{zero,one}"} *}
  3723 ML {* @{typ "'a => 'b"} *}
  3724 ML {* @{term "%x. x"} *}
  3725 ML {* @{prop "x == y"} *}
  3726 ML {* @{ctyp "'a => 'b"} *}
  3727 ML {* @{cterm "%x. x"} *}
  3728 ML {* @{cprop "x == y"} *}
  3729 ML {* @{thm asm_rl} *}
  3730 ML {* @{thms asm_rl} *}
  3731 ML {* @{type_name c} *}
  3732 ML {* @{type_syntax c} *}
  3733 ML {* @{const_name c} *}
  3734 ML {* @{const_syntax c} *}
  3735 ML {* @{context} *}
  3736 ML {* @{theory} *}
  3737 ML {* @{theory Pure} *}
  3738 ML {* @{theory_ref} *}
  3739 ML {* @{theory_ref Pure} *}
  3740 ML {* @{simpset} *}
  3741 ML {* @{claset} *}
  3742 ML {* @{clasimpset} *}
  3743 
  3744 The same works for sources being ``used'' within an Isar context.
  3745 
  3746 * ML in Isar: improved error reporting; extra verbosity with
  3747 ML_Context.trace enabled.
  3748 
  3749 * Pure/General/table.ML: the join operations now works via exceptions
  3750 DUP/SAME instead of type option. This is simpler in simple cases, and
  3751 admits slightly more efficient complex applications.
  3752 
  3753 * Pure: 'advanced' translation functions (parse_translation etc.) now
  3754 use Context.generic instead of just theory.
  3755 
  3756 * Pure: datatype Context.generic joins theory/Proof.context and
  3757 provides some facilities for code that works in either kind of
  3758 context, notably GenericDataFun for uniform theory and proof data.
  3759 
  3760 * Pure: simplified internal attribute type, which is now always
  3761 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  3762 local (Proof.context) attributes have been discontinued, while
  3763 minimizing code duplication. Thm.rule_attribute and
  3764 Thm.declaration_attribute build canonical attributes; see also structure
  3765 Context for further operations on Context.generic, notably
  3766 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  3767 declarations and definitions.
  3768 
  3769 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  3770 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  3771 init only required for impure data. INCOMPATIBILITY: empty really need
  3772 to be empty (no dependencies on theory content!)
  3773 
  3774 * Pure/kernel: consts certification ignores sort constraints given in
  3775 signature declarations. (This information is not relevant to the
  3776 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  3777 potential INCOMPATIBILITY.
  3778 
  3779 * Pure: axiomatic type classes are now purely definitional, with
  3780 explicit proofs of class axioms and super class relations performed
  3781 internally. See Pure/axclass.ML for the main internal interfaces --
  3782 notably AxClass.define_class supercedes AxClass.add_axclass, and
  3783 AxClass.axiomatize_class/classrel/arity supersede
  3784 Sign.add_classes/classrel/arities.
  3785 
  3786 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  3787 global/local versions on theory vs. Proof.context have been
  3788 discontinued; Attrib.syntax and Method.syntax have been adapted
  3789 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  3790 attributes, methods, etc.
  3791 
  3792 * Pure: several functions of signature "... -> theory -> theory * ..."
  3793 have been reoriented to "... -> theory -> ... * theory" in order to
  3794 allow natural usage in combination with the ||>, ||>>, |-> and
  3795 fold_map combinators.
  3796 
  3797 * Pure: official theorem names (closed derivations) and additional
  3798 comments (tags) are now strictly separate.  Name hints -- which are
  3799 maintained as tags -- may be attached any time without affecting the
  3800 derivation.
  3801 
  3802 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  3803 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  3804 achieve the old behaviour.
  3805 
  3806 * Pure: the "Goal" constant is now called "prop", supporting a
  3807 slightly more general idea of ``protecting'' meta-level rule
  3808 statements.
  3809 
  3810 * Pure: Logic.(un)varify only works in a global context, which is now
  3811 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  3812 Logic.legacy_(un)varify as temporary workaround.
  3813 
  3814 * Pure: structure Name provides scalable operations for generating
  3815 internal variable names, notably Name.variants etc.  This replaces
  3816 some popular functions from term.ML:
  3817 
  3818   Term.variant		->  Name.variant
  3819   Term.variantlist	->  Name.variant_list
  3820   Term.invent_names	->  Name.invent_list
  3821 
  3822 Note that low-level renaming rarely occurs in new code -- operations
  3823 from structure Variable are used instead (see below).
  3824 
  3825 * Pure: structure Variable provides fundamental operations for proper
  3826 treatment of fixed/schematic variables in a context.  For example,
  3827 Variable.import introduces fixes for schematics of given facts and
  3828 Variable.export reverses the effect (up to renaming) -- this replaces
  3829 various freeze_thaw operations.
  3830 
  3831 * Pure: structure Goal provides simple interfaces for
  3832 init/conclude/finish and tactical prove operations (replacing former
  3833 Tactic.prove).  Goal.prove is the canonical way to prove results
  3834 within a given context; Goal.prove_global is a degraded version for
  3835 theory level goals, including a global Drule.standard.  Note that
  3836 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  3837 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  3838 in a locale context).
  3839 
  3840 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  3841 and type checking (Syntax.check_term etc.), with common combinations
  3842 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  3843 which are considered legacy and await removal.
  3844 
  3845 * Pure/Syntax: generic interfaces for type unchecking
  3846 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  3847 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  3848 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  3849 available for convenience, but refer to the very same operations using
  3850 a mere theory instead of a full context.
  3851 
  3852 * Isar: simplified treatment of user-level errors, using exception
  3853 ERROR of string uniformly.  Function error now merely raises ERROR,
  3854 without any side effect on output channels.  The Isar toplevel takes
  3855 care of proper display of ERROR exceptions.  ML code may use plain
  3856 handle/can/try; cat_error may be used to concatenate errors like this:
  3857 
  3858   ... handle ERROR msg => cat_error msg "..."
  3859 
  3860 Toplevel ML code (run directly or through the Isar toplevel) may be
  3861 embedded into the Isar toplevel with exception display/debug like
  3862 this:
  3863 
  3864   Isar.toplevel (fn () => ...)
  3865 
  3866 INCOMPATIBILITY, removed special transform_error facilities, removed
  3867 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  3868 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  3869 -- use plain ERROR instead.
  3870 
  3871 * Isar: theory setup now has type (theory -> theory), instead of a
  3872 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  3873 
  3874 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  3875 ProofContext.debug/verbose flags.
  3876 
  3877 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  3878 theory before entering a proof state.  Transactions now always see a
  3879 quasi-functional intermediate checkpoint, both in interactive and
  3880 batch mode.
  3881 
  3882 * Isar: simplified interfaces for outer syntax.  Renamed
  3883 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  3884 OuterSyntax.add_parsers -- this functionality is now included in
  3885 OuterSyntax.command etc.  INCOMPATIBILITY.
  3886 
  3887 * Simplifier: the simpset of a running simplification process now
  3888 contains a proof context (cf. Simplifier.the_context), which is the
  3889 very context that the initial simpset has been retrieved from (by
  3890 simpset_of/local_simpset_of).  Consequently, all plug-in components
  3891 (solver, looper etc.) may depend on arbitrary proof data.
  3892 
  3893 * Simplifier.inherit_context inherits the proof context (plus the
  3894 local bounds) of the current simplification process; any simproc
  3895 etc. that calls the Simplifier recursively should do this!  Removed
  3896 former Simplifier.inherit_bounds, which is already included here --
  3897 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  3898 specify an explicit context using Simplifier.context/theory_context.
  3899 
  3900 * Simplifier/Classical Reasoner: more abstract interfaces
  3901 change_simpset/claset for modifying the simpset/claset reference of a
  3902 theory; raw versions simpset/claset_ref etc. have been discontinued --
  3903 INCOMPATIBILITY.
  3904 
  3905 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  3906 "Trueprop" etc.
  3907 
  3908 
  3909 *** System ***
  3910 
  3911 * settings: the default heap location within ISABELLE_HOME_USER now
  3912 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  3913 Isabelle installations.
  3914 
  3915 * isabelle-process: option -S (secure mode) disables some critical
  3916 operations, notably runtime compilation and evaluation of ML source
  3917 code.
  3918 
  3919 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  3920 
  3921 * Support for parallel execution, using native multicore support of
  3922 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  3923 independent theories, according to the given theory header
  3924 specifications. The maximum number of worker threads is specified via
  3925 usedir option -M or the "max-threads" setting in Proof General. A
  3926 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  3927 to 6 on a 8-core machine.  User-code needs to observe certain
  3928 guidelines for thread-safe programming, see appendix A in the Isar
  3929 Implementation manual.
  3930 
  3931 
  3932 
  3933 New in Isabelle2005 (October 2005)
  3934 ----------------------------------
  3935 
  3936 *** General ***
  3937 
  3938 * Theory headers: the new header syntax for Isar theories is
  3939 
  3940   theory <name>
  3941   imports <theory1> ... <theoryN>
  3942   uses <file1> ... <fileM>
  3943   begin
  3944 
  3945 where the 'uses' part is optional.  The previous syntax
  3946 
  3947   theory <name> = <theory1> + ... + <theoryN>:
  3948 
  3949 will disappear in the next release.  Use isatool fixheaders to convert
  3950 existing theory files.  Note that there is no change in ancient
  3951 non-Isar theories now, but these will disappear soon.
  3952 
  3953 * Theory loader: parent theories can now also be referred to via
  3954 relative and absolute paths.
  3955 
  3956 * Command 'find_theorems' searches for a list of criteria instead of a
  3957 list of constants. Known criteria are: intro, elim, dest, name:string,
  3958 simp:term, and any term. Criteria can be preceded by '-' to select
  3959 theorems that do not match. Intro, elim, dest select theorems that
  3960 match the current goal, name:s selects theorems whose fully qualified
  3961 name contain s, and simp:term selects all simplification rules whose
  3962 lhs match term.  Any other term is interpreted as pattern and selects
  3963 all theorems matching the pattern. Available in ProofGeneral under
  3964 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  3965 
  3966   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  3967 
  3968 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  3969 matching the current goal as introduction rule and not having "HOL."
  3970 in their name (i.e. not being defined in theory HOL).
  3971 
  3972 * Command 'thms_containing' has been discontinued in favour of
  3973 'find_theorems'; INCOMPATIBILITY.
  3974 
  3975 * Communication with Proof General is now 8bit clean, which means that
  3976 Unicode text in UTF-8 encoding may be used within theory texts (both
  3977 formal and informal parts).  Cf. option -U of the Isabelle Proof
  3978 General interface.  Here are some simple examples (cf. src/HOL/ex):
  3979 
  3980   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  3981   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  3982 
  3983 * Improved efficiency of the Simplifier and, to a lesser degree, the
  3984 Classical Reasoner.  Typical big applications run around 2 times
  3985 faster.
  3986 
  3987 
  3988 *** Document preparation ***
  3989 
  3990 * Commands 'display_drafts' and 'print_drafts' perform simple output
  3991 of raw sources.  Only those symbols that do not require additional
  3992 LaTeX packages (depending on comments in isabellesym.sty) are
  3993 displayed properly, everything else is left verbatim.  isatool display
  3994 and isatool print are used as front ends (these are subject to the
  3995 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  3996 
  3997 * Command tags control specific markup of certain regions of text,
  3998 notably folding and hiding.  Predefined tags include "theory" (for
  3999 theory begin and end), "proof" for proof commands, and "ML" for
  4000 commands involving ML code; the additional tags "visible" and
  4001 "invisible" are unused by default.  Users may give explicit tag
  4002 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4003 interpretation of tags is determined by the LaTeX job during document
  4004 preparation: see option -V of isatool usedir, or options -n and -t of
  4005 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4006 \isadroptag.
  4007 
  4008 Several document versions may be produced at the same time via isatool
  4009 usedir (the generated index.html will link all of them).  Typical
  4010 specifications include ''-V document=theory,proof,ML'' to present
  4011 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4012 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4013 these parts without any formal replacement text.  The Isabelle site
  4014 default settings produce ''document'' and ''outline'' versions as
  4015 specified above.
  4016 
  4017 * Several new antiquotations:
  4018 
  4019   @{term_type term} prints a term with its type annotated;
  4020 
  4021   @{typeof term} prints the type of a term;
  4022 
  4023   @{const const} is the same as @{term const}, but checks that the
  4024   argument is a known logical constant;
  4025 
  4026   @{term_style style term} and @{thm_style style thm} print a term or
  4027   theorem applying a "style" to it
  4028 
  4029   @{ML text}
  4030 
  4031 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4032 definitions, equations, inequations etc., 'concl' printing only the
  4033 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4034 to print the specified premise.  TermStyle.add_style provides an ML
  4035 interface for introducing further styles.  See also the "LaTeX Sugar"
  4036 document practical applications.  The ML antiquotation prints
  4037 type-checked ML expressions verbatim.
  4038 
  4039 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4040 and 'text' support optional locale specification '(in loc)', which
  4041 specifies the default context for interpreting antiquotations.  For
  4042 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4043 
  4044 * Option 'locale=NAME' of antiquotations specifies an alternative
  4045 context interpreting the subsequent argument.  For example: @{thm
  4046 [locale=lattice] inf_assoc}.
  4047 
  4048 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4049 a proof context.
  4050 
  4051 * Proper output of antiquotations for theory commands involving a
  4052 proof context (such as 'locale' or 'theorem (in loc) ...').
  4053 
  4054 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4055 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4056 
  4057 * isatool usedir: new option -C (default true) controls whether option
  4058 -D should include a copy of the original document directory; -C false
  4059 prevents unwanted effects such as copying of administrative CVS data.
  4060 
  4061 
  4062 *** Pure ***
  4063 
  4064 * Considerably improved version of 'constdefs' command.  Now performs
  4065 automatic type-inference of declared constants; additional support for
  4066 local structure declarations (cf. locales and HOL records), see also
  4067 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4068 sequential dependencies of definitions within a single 'constdefs'
  4069 section; moreover, the declared name needs to be an identifier.  If
  4070 all fails, consider to fall back on 'consts' and 'defs' separately.
  4071 
  4072 * Improved indexed syntax and implicit structures.  First of all,
  4073 indexed syntax provides a notational device for subscripted
  4074 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4075 expressions.  Secondly, in a local context with structure
  4076 declarations, number indexes \<^sub>n or the empty index (default
  4077 number 1) refer to a certain fixed variable implicitly; option
  4078 show_structs controls printing of implicit structures.  Typical
  4079 applications of these concepts involve record types and locales.
  4080 
  4081 * New command 'no_syntax' removes grammar declarations (and
  4082 translations) resulting from the given syntax specification, which is
  4083 interpreted in the same manner as for the 'syntax' command.
  4084 
  4085 * 'Advanced' translation functions (parse_translation etc.) may depend
  4086 on the signature of the theory context being presently used for
  4087 parsing/printing, see also isar-ref manual.
  4088 
  4089 * Improved 'oracle' command provides a type-safe interface to turn an
  4090 ML expression of type theory -> T -> term into a primitive rule of
  4091 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4092 is already included here); see also FOL/ex/IffExample.thy;
  4093 INCOMPATIBILITY.
  4094 
  4095 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4096 before); "cI" is no longer bound, use "c.intro" instead.
  4097 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4098 axclasses vs. locales.
  4099 
  4100 * Improved internal renaming of symbolic identifiers -- attach primes
  4101 instead of base 26 numbers.
  4102 
  4103 * New flag show_question_marks controls printing of leading question
  4104 marks in schematic variable names.
  4105 
  4106 * In schematic variable names, *any* symbol following \<^isub> or
  4107 \<^isup> is now treated as part of the base name.  For example, the
  4108 following works without printing of awkward ".0" indexes:
  4109 
  4110   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4111     by simp
  4112 
  4113 * Inner syntax includes (*(*nested*) comments*).
  4114 
  4115 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4116 annotations as "(00...)".
  4117 
  4118 * Clear separation of logical types and nonterminals, where the latter
  4119 may only occur in 'syntax' specifications or type abbreviations.
  4120 Before that distinction was only partially implemented via type class
  4121 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4122 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4123 exotic syntax specifications may require further adaption
  4124 (e.g. Cube/Cube.thy).
  4125 
  4126 * Removed obsolete type class "logic", use the top sort {} instead.
  4127 Note that non-logical types should be declared as 'nonterminals'
  4128 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4129 specifications.
  4130 
  4131 * Attributes 'induct' and 'cases': type or set names may now be
  4132 locally fixed variables as well.
  4133 
  4134 * Simplifier: can now control the depth to which conditional rewriting
  4135 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4136 Limit.
  4137 
  4138 * Simplifier: simplification procedures may now take the current
  4139 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4140 interface), which is very useful for calling the Simplifier
  4141 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4142 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4143 low-level mk_simproc no longer applies Logic.varify internally, to
  4144 allow for use in a context of fixed variables.
  4145 
  4146 * thin_tac now works even if the assumption being deleted contains !!
  4147 or ==>.  More generally, erule now works even if the major premise of
  4148 the elimination rule contains !! or ==>.
  4149 
  4150 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4151 
  4152 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4153 from Pure, which contains all common declarations already.  Both
  4154 theories are defined via plain Isabelle/Isar .thy files.
  4155 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4156 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4157 use isatool fixcpure to adapt your theory and ML sources.
  4158 
  4159 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4160 selections of theorems in named facts via index ranges.
  4161 
  4162 * 'print_theorems': in theory mode, really print the difference
  4163 wrt. the last state (works for interactive theory development only),
  4164 in proof mode print all local facts (cf. 'print_facts');
  4165 
  4166 * 'hide': option '(open)' hides only base names.
  4167 
  4168 * More efficient treatment of intermediate checkpoints in interactive
  4169 theory development.
  4170 
  4171 * Code generator is now invoked via code_module (incremental code
  4172 generation) and code_library (modular code generation, ML structures
  4173 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4174 must be quoted when used as identifiers.
  4175 
  4176 * New 'value' command for reading, evaluating and printing terms using
  4177 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4178 quoted when used as identifier.
  4179 
  4180 
  4181 *** Locales ***
  4182 
  4183 * New commands for the interpretation of locale expressions in
  4184 theories (1), locales (2) and proof contexts (3).  These generate
  4185 proof obligations from the expression specification.  After the
  4186 obligations have been discharged, theorems of the expression are added
  4187 to the theory, target locale or proof context.  The synopsis of the
  4188 commands is a follows:
  4189 
  4190   (1) interpretation expr inst
  4191   (2) interpretation target < expr
  4192   (3) interpret expr inst
  4193 
  4194 Interpretation in theories and proof contexts require a parameter
  4195 instantiation of terms from the current context.  This is applied to
  4196 specifications and theorems of the interpreted expression.
  4197 Interpretation in locales only permits parameter renaming through the
  4198 locale expression.  Interpretation is smart in that interpretations
  4199 that are active already do not occur in proof obligations, neither are
  4200 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4201 inspect active interpretations of a particular locale.  For details,
  4202 see the Isar Reference manual.  Examples can be found in
  4203 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4204 
  4205 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4206 'interpret' instead.
  4207 
  4208 * New context element 'constrains' for adding type constraints to
  4209 parameters.
  4210 
  4211 * Context expressions: renaming of parameters with syntax
  4212 redeclaration.
  4213 
  4214 * Locale declaration: 'includes' disallowed.
  4215 
  4216 * Proper static binding of attribute syntax -- i.e. types / terms /
  4217 facts mentioned as arguments are always those of the locale definition
  4218 context, independently of the context of later invocations.  Moreover,
  4219 locale operations (renaming and type / term instantiation) are applied
  4220 to attribute arguments as expected.
  4221 
  4222 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4223 actual attributes; rare situations may require Attrib.attribute to
  4224 embed those attributes into Attrib.src that lack concrete syntax.
  4225 Attribute implementations need to cooperate properly with the static
  4226 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4227 Attrib.XXX_thm etc. already do the right thing without further
  4228 intervention.  Only unusual applications -- such as "where" or "of"
  4229 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4230 on the context and the facts involved -- may have to assign parsed
  4231 values to argument tokens explicitly.
  4232 
  4233 * Changed parameter management in theorem generation for long goal
  4234 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4235 theorem statement in rare situations.
  4236 
  4237 * Locale inspection command 'print_locale' omits notes elements.  Use
  4238 'print_locale!' to have them included in the output.
  4239 
  4240 
  4241 *** Provers ***
  4242 
  4243 * Provers/hypsubst.ML: improved version of the subst method, for
  4244 single-step rewriting: it now works in bound variable contexts. New is
  4245 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4246 rewrite a different subterm than the original subst method, which is
  4247 still available as 'simplesubst'.
  4248 
  4249 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4250 and quasi orders.
  4251 
  4252 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4253 reflexive-transitive closure of relations.
  4254 
  4255 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4256 limit (previously hard-coded with a value of 20) user-definable.
  4257 
  4258 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4259 is peformed already.  Object-logics merely need to finish their
  4260 initial simpset configuration as before.  INCOMPATIBILITY.
  4261 
  4262 
  4263 *** HOL ***
  4264 
  4265 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4266 
  4267   syntax (epsilon)
  4268     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4269 
  4270 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4271 and x-symbol; use option '-m epsilon' to get it actually printed.
  4272 Moreover, the mathematically important symbolic identifier \<epsilon>
  4273 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4274 
  4275 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  4276 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  4277 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  4278 support corresponding Isar calculations.
  4279 
  4280 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  4281 instead of ":".
  4282 
  4283 * theory SetInterval: changed the syntax for open intervals:
  4284 
  4285   Old       New
  4286   {..n(}    {..<n}
  4287   {)n..}    {n<..}
  4288   {m..n(}   {m..<n}
  4289   {)m..n}   {m<..n}
  4290   {)m..n(}  {m<..<n}
  4291 
  4292 The old syntax is still supported but will disappear in the next
  4293 release.  For conversion use the following Emacs search and replace
  4294 patterns (these are not perfect but work quite well):
  4295 
  4296   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  4297   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  4298 
  4299 * Theory Commutative_Ring (in Library): method comm_ring for proving
  4300 equalities in commutative rings; method 'algebra' provides a generic
  4301 interface.
  4302 
  4303 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  4304 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  4305 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  4306 be a tuple pattern.
  4307 
  4308 Some new syntax forms are available:
  4309 
  4310   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  4311   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  4312   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  4313   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  4314 
  4315 The latter form "\<Sum>x < k. e" used to be based on a separate
  4316 function "Summation", which has been discontinued.
  4317 
  4318 * theory Finite_Set: in structured induction proofs, the insert case
  4319 is now 'case (insert x F)' instead of the old counterintuitive 'case
  4320 (insert F x)'.
  4321 
  4322 * The 'refute' command has been extended to support a much larger
  4323 fragment of HOL, including axiomatic type classes, constdefs and
  4324 typedefs, inductive datatypes and recursion.
  4325 
  4326 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  4327 Requires zChaff with proof generation to be installed.  See
  4328 HOL/ex/SAT_Examples.thy for examples.
  4329 
  4330 * Datatype induction via method 'induct' now preserves the name of the
  4331 induction variable. For example, when proving P(xs::'a list) by
  4332 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  4333 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  4334 in unstructured proof scripts.
  4335 
  4336 * Reworked implementation of records.  Improved scalability for
  4337 records with many fields, avoiding performance problems for type
  4338 inference. Records are no longer composed of nested field types, but
  4339 of nested extension types. Therefore the record type only grows linear
  4340 in the number of extensions and not in the number of fields.  The
  4341 top-level (users) view on records is preserved.  Potential
  4342 INCOMPATIBILITY only in strange cases, where the theory depends on the
  4343 old record representation. The type generated for a record is called
  4344 <record_name>_ext_type.
  4345 
  4346 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  4347 proofs triggered by a record definition or a simproc (if
  4348 quick_and_dirty is enabled).  Definitions of large records can take
  4349 quite long.
  4350 
  4351 New simproc record_upd_simproc for simplification of multiple record
  4352 updates enabled by default.  Moreover, trivial updates are also
  4353 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  4354 occasionally, since simplification is more powerful by default.
  4355 
  4356 * typedef: proper support for polymorphic sets, which contain extra
  4357 type-variables in the term.
  4358 
  4359 * Simplifier: automatically reasons about transitivity chains
  4360 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  4361 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  4362 old proofs break occasionally as simplification may now solve more
  4363 goals than previously.
  4364 
  4365 * Simplifier: converts x <= y into x = y if assumption y <= x is
  4366 present.  Works for all partial orders (class "order"), in particular
  4367 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  4368 just like y <= x.
  4369 
  4370 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  4371 bound variable or a constant then the let is unfolded.  Otherwise
  4372 first a is simplified to b, and then f b is simplified to g. If
  4373 possible we abstract b from g arriving at "let x = b in h x",
  4374 otherwise we unfold the let and arrive at g.  The simproc can be
  4375 enabled/disabled by the reference use_let_simproc.  Potential
  4376 INCOMPATIBILITY since simplification is more powerful by default.
  4377 
  4378 * Classical reasoning: the meson method now accepts theorems as arguments.
  4379 
  4380 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  4381 jobs to provide advice on the provability of subgoals.
  4382 
  4383 * Theory OrderedGroup and Ring_and_Field: various additions and
  4384 improvements to faciliate calculations involving equalities and
  4385 inequalities.
  4386 
  4387 The following theorems have been eliminated or modified
  4388 (INCOMPATIBILITY):
  4389 
  4390   abs_eq             now named abs_of_nonneg
  4391   abs_of_ge_0        now named abs_of_nonneg
  4392   abs_minus_eq       now named abs_of_nonpos
  4393   imp_abs_id         now named abs_of_nonneg
  4394   imp_abs_neg_id     now named abs_of_nonpos
  4395   mult_pos           now named mult_pos_pos
  4396   mult_pos_le        now named mult_nonneg_nonneg
  4397   mult_pos_neg_le    now named mult_nonneg_nonpos
  4398   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  4399   mult_neg           now named mult_neg_neg
  4400   mult_neg_le        now named mult_nonpos_nonpos
  4401 
  4402 * The following lemmas in Ring_and_Field have been added to the simplifier:
  4403      
  4404      zero_le_square
  4405      not_square_less_zero 
  4406 
  4407   The following lemmas have been deleted from Real/RealPow:
  4408   
  4409      realpow_zero_zero
  4410      realpow_two
  4411      realpow_less
  4412      zero_le_power
  4413      realpow_two_le
  4414      abs_realpow_two
  4415      realpow_two_abs     
  4416 
  4417 * Theory Parity: added rules for simplifying exponents.
  4418 
  4419 * Theory List:
  4420 
  4421 The following theorems have been eliminated or modified
  4422 (INCOMPATIBILITY):
  4423 
  4424   list_all_Nil       now named list_all.simps(1)
  4425   list_all_Cons      now named list_all.simps(2)
  4426   list_all_conv      now named list_all_iff
  4427   set_mem_eq         now named mem_iff
  4428 
  4429 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  4430 asymptotic "big O" calculations.  See the notes in BigO.thy.
  4431 
  4432 
  4433 *** HOL-Complex ***
  4434 
  4435 * Theory RealDef: better support for embedding natural numbers and
  4436 integers in the reals.
  4437 
  4438 The following theorems have been eliminated or modified
  4439 (INCOMPATIBILITY):
  4440 
  4441   exp_ge_add_one_self  now requires no hypotheses
  4442   real_of_int_add      reversed direction of equality (use [symmetric])
  4443   real_of_int_minus    reversed direction of equality (use [symmetric])
  4444   real_of_int_diff     reversed direction of equality (use [symmetric])
  4445   real_of_int_mult     reversed direction of equality (use [symmetric])
  4446 
  4447 * Theory RComplete: expanded support for floor and ceiling functions.
  4448 
  4449 * Theory Ln is new, with properties of the natural logarithm
  4450 
  4451 * Hyperreal: There is a new type constructor "star" for making
  4452 nonstandard types.  The old type names are now type synonyms:
  4453 
  4454   hypreal = real star
  4455   hypnat = nat star
  4456   hcomplex = complex star
  4457 
  4458 * Hyperreal: Many groups of similarly-defined constants have been
  4459 replaced by polymorphic versions (INCOMPATIBILITY):
  4460 
  4461   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  4462 
  4463   starset      <-- starsetNat, starsetC
  4464   *s*          <-- *sNat*, *sc*
  4465   starset_n    <-- starsetNat_n, starsetC_n
  4466   *sn*         <-- *sNatn*, *scn*
  4467   InternalSets <-- InternalNatSets, InternalCSets
  4468 
  4469   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  4470   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  4471   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  4472   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  4473   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  4474 
  4475 * Hyperreal: Many type-specific theorems have been removed in favor of
  4476 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  4477 
  4478   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  4479   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  4480   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  4481   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  4482   right_minus <-- hypreal_add_minus
  4483   left_minus <-- {hypreal,hcomplex}_add_minus_left
  4484   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  4485   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  4486   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  4487   mult_1_right <-- hcomplex_mult_one_right
  4488   mult_zero_left <-- hcomplex_mult_zero_left
  4489   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  4490   right_distrib <-- hypnat_add_mult_distrib2
  4491   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  4492   right_inverse <-- hypreal_mult_inverse
  4493   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  4494   order_refl <-- {hypreal,hypnat}_le_refl
  4495   order_trans <-- {hypreal,hypnat}_le_trans
  4496   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  4497   order_less_le <-- {hypreal,hypnat}_less_le
  4498   linorder_linear <-- {hypreal,hypnat}_le_linear
  4499   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  4500   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  4501   add_nonneg_nonneg <-- hypreal_le_add_order
  4502 
  4503 * Hyperreal: Separate theorems having to do with type-specific
  4504 versions of constants have been merged into theorems that apply to the
  4505 new polymorphic constants (INCOMPATIBILITY):
  4506 
  4507   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  4508   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  4509   STAR_Un <-- {STAR,NatStar,STARC}_Un
  4510   STAR_Int <-- {STAR,NatStar,STARC}_Int
  4511   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  4512   STAR_subset <-- {STAR,NatStar,STARC}_subset
  4513   STAR_mem <-- {STAR,NatStar,STARC}_mem
  4514   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  4515   STAR_diff <-- {STAR,STARC}_diff
  4516   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  4517     STARC_hcomplex_of_complex}_image_subset
  4518   starset_n_Un <-- starset{Nat,C}_n_Un
  4519   starset_n_Int <-- starset{Nat,C}_n_Int
  4520   starset_n_Compl <-- starset{Nat,C}_n_Compl
  4521   starset_n_diff <-- starset{Nat,C}_n_diff
  4522   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  4523   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  4524   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  4525   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  4526   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  4527   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  4528   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  4529   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  4530   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  4531   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  4532   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  4533   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  4534   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  4535   starfun_diff <-- starfun{C,RC,CR}_diff
  4536   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  4537   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  4538   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  4539   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  4540   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  4541   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  4542   starfun_Id <-- starfunC_Id
  4543   starfun_approx <-- starfun{Nat,CR}_approx
  4544   starfun_capprox <-- starfun{C,RC}_capprox
  4545   starfun_abs <-- starfunNat_rabs
  4546   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  4547   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  4548   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  4549   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  4550   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  4551   starfun_add_approx <-- starfunCR_add_approx
  4552   starfun_inverse_inverse <-- starfunC_inverse_inverse
  4553   starfun_divide <-- starfun{C,CR,RC}_divide
  4554   starfun_n <-- starfun{Nat,C}_n
  4555   starfun_n_mult <-- starfun{Nat,C}_n_mult
  4556   starfun_n_add <-- starfun{Nat,C}_n_add
  4557   starfun_n_add_minus <-- starfunNat_n_add_minus
  4558   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  4559   starfun_n_minus <-- starfun{Nat,C}_n_minus
  4560   starfun_n_eq <-- starfun{Nat,C}_n_eq
  4561 
  4562   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  4563   star_n_minus <-- {hypreal,hcomplex}_minus
  4564   star_n_diff <-- {hypreal,hcomplex}_diff
  4565   star_n_mult <-- {hypreal,hcomplex}_mult
  4566   star_n_inverse <-- {hypreal,hcomplex}_inverse
  4567   star_n_le <-- {hypreal,hypnat}_le
  4568   star_n_less <-- {hypreal,hypnat}_less
  4569   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  4570   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  4571   star_n_abs <-- hypreal_hrabs
  4572   star_n_divide <-- hcomplex_divide
  4573 
  4574   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  4575   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  4576   star_of_diff <-- hypreal_of_real_diff
  4577   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  4578   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  4579   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  4580   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  4581   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  4582   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  4583   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  4584   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  4585   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  4586   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  4587   star_of_number_of <-- {hypreal,hcomplex}_number_of
  4588   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  4589   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  4590   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  4591   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  4592   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  4593   star_of_power <-- hypreal_of_real_power
  4594   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  4595 
  4596 * Hyperreal: new method "transfer" that implements the transfer
  4597 principle of nonstandard analysis. With a subgoal that mentions
  4598 nonstandard types like "'a star", the command "apply transfer"
  4599 replaces it with an equivalent one that mentions only standard types.
  4600 To be successful, all free variables must have standard types; non-
  4601 standard variables must have explicit universal quantifiers.
  4602 
  4603 * Hyperreal: A theory of Taylor series.
  4604 
  4605 
  4606 *** HOLCF ***
  4607 
  4608 * Discontinued special version of 'constdefs' (which used to support
  4609 continuous functions) in favor of the general Pure one with full
  4610 type-inference.
  4611 
  4612 * New simplification procedure for solving continuity conditions; it
  4613 is much faster on terms with many nested lambda abstractions (cubic
  4614 instead of exponential time).
  4615 
  4616 * New syntax for domain package: selector names are now optional.
  4617 Parentheses should be omitted unless argument is lazy, for example:
  4618 
  4619   domain 'a stream = cons "'a" (lazy "'a stream")
  4620 
  4621 * New command 'fixrec' for defining recursive functions with pattern
  4622 matching; defining multiple functions with mutual recursion is also
  4623 supported.  Patterns may include the constants cpair, spair, up, sinl,
  4624 sinr, or any data constructor defined by the domain package. The given
  4625 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  4626 syntax and examples.
  4627 
  4628 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  4629 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  4630 but the proof obligation additionally includes an admissibility
  4631 requirement. The packages generate instances of class cpo or pcpo,
  4632 with continuity and strictness theorems for Rep and Abs.
  4633 
  4634 * HOLCF: Many theorems have been renamed according to a more standard naming
  4635 scheme (INCOMPATIBILITY):
  4636 
  4637   foo_inject:  "foo$x = foo$y ==> x = y"
  4638   foo_eq:      "(foo$x = foo$y) = (x = y)"
  4639   foo_less:    "(foo$x << foo$y) = (x << y)"
  4640   foo_strict:  "foo$UU = UU"
  4641   foo_defined: "... ==> foo$x ~= UU"
  4642   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  4643 
  4644 
  4645 *** ZF ***
  4646 
  4647 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  4648 including the First Isomorphism Theorem (on quotienting by the kernel
  4649 of a homomorphism).
  4650 
  4651 * ZF/Simplifier: install second copy of type solver that actually
  4652 makes use of TC rules declared to Isar proof contexts (or locales);
  4653 the old version is still required for ML proof scripts.
  4654 
  4655 
  4656 *** Cube ***
  4657 
  4658 * Converted to Isar theory format; use locales instead of axiomatic
  4659 theories.
  4660 
  4661 
  4662 *** ML ***
  4663 
  4664 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  4665 for ||>, ||>>, |>>,
  4666 
  4667 * Pure/library.ML no longer defines its own option datatype, but uses
  4668 that of the SML basis, which has constructors NONE and SOME instead of
  4669 None and Some, as well as exception Option.Option instead of OPTION.
  4670 The functions the, if_none, is_some, is_none have been adapted
  4671 accordingly, while Option.map replaces apsome.
  4672 
  4673 * Pure/library.ML: the exception LIST has been given up in favour of
  4674 the standard exceptions Empty and Subscript, as well as
  4675 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  4676 superceded by the standard hd and tl functions etc.
  4677 
  4678 A number of basic list functions are no longer exported to the ML
  4679 toplevel, as they are variants of predefined functions.  The following
  4680 suggests how one can translate existing code:
  4681 
  4682     rev_append xs ys = List.revAppend (xs, ys)
  4683     nth_elem (i, xs) = List.nth (xs, i)
  4684     last_elem xs = List.last xs
  4685     flat xss = List.concat xss
  4686     seq fs = List.app fs
  4687     partition P xs = List.partition P xs
  4688     mapfilter f xs = List.mapPartial f xs
  4689 
  4690 * Pure/library.ML: several combinators for linear functional
  4691 transformations, notably reverse application and composition:
  4692 
  4693   x |> f                f #> g
  4694   (x, y) |-> f          f #-> g
  4695 
  4696 * Pure/library.ML: introduced/changed precedence of infix operators:
  4697 
  4698   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  4699   infix 2 ?;
  4700   infix 3 o oo ooo oooo;
  4701   infix 4 ~~ upto downto;
  4702 
  4703 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  4704 infix operators.
  4705 
  4706 * Pure/library.ML: natural list combinators fold, fold_rev, and
  4707 fold_map support linear functional transformations and nesting.  For
  4708 example:
  4709 
  4710   fold f [x1, ..., xN] y =
  4711     y |> f x1 |> ... |> f xN
  4712 
  4713   (fold o fold) f [xs1, ..., xsN] y =
  4714     y |> fold f xs1 |> ... |> fold f xsN
  4715 
  4716   fold f [x1, ..., xN] =
  4717     f x1 #> ... #> f xN
  4718 
  4719   (fold o fold) f [xs1, ..., xsN] =
  4720     fold f xs1 #> ... #> fold f xsN
  4721 
  4722 * Pure/library.ML: the following selectors on type 'a option are
  4723 available:
  4724 
  4725   the:               'a option -> 'a  (*partial*)
  4726   these:             'a option -> 'a  where 'a = 'b list
  4727   the_default: 'a -> 'a option -> 'a
  4728   the_list:          'a option -> 'a list
  4729 
  4730 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  4731 basic operations for association lists, following natural argument
  4732 order; moreover the explicit equality predicate passed here avoids
  4733 potentially expensive polymorphic runtime equality checks.
  4734 The old functions may be expressed as follows:
  4735 
  4736   assoc = uncurry (AList.lookup (op =))
  4737   assocs = these oo AList.lookup (op =)
  4738   overwrite = uncurry (AList.update (op =)) o swap
  4739 
  4740 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  4741 
  4742   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  4743   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  4744 
  4745 replacing make_keylist and keyfilter (occassionally used)
  4746 Naive rewrites:
  4747 
  4748   make_keylist = AList.make
  4749   keyfilter = AList.find (op =)
  4750 
  4751 * eq_fst and eq_snd now take explicit equality parameter, thus
  4752   avoiding eqtypes. Naive rewrites:
  4753 
  4754     eq_fst = eq_fst (op =)
  4755     eq_snd = eq_snd (op =)
  4756 
  4757 * Removed deprecated apl and apr (rarely used).
  4758   Naive rewrites:
  4759 
  4760     apl (n, op) =>>= curry op n
  4761     apr (op, m) =>>= fn n => op (n, m)
  4762 
  4763 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  4764 provides a reasonably efficient light-weight implementation of sets as
  4765 lists.
  4766 
  4767 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  4768 few new operations; existing lookup and update are now curried to
  4769 follow natural argument order (for use with fold etc.);
  4770 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  4771 
  4772 * Pure/General: output via the Isabelle channels of
  4773 writeln/warning/error etc. is now passed through Output.output, with a
  4774 hook for arbitrary transformations depending on the print_mode
  4775 (cf. Output.add_mode -- the first active mode that provides a output
  4776 function wins).  Already formatted output may be embedded into further
  4777 text via Output.raw; the result of Pretty.string_of/str_of and derived
  4778 functions (string_of_term/cterm/thm etc.) is already marked raw to
  4779 accommodate easy composition of diagnostic messages etc.  Programmers
  4780 rarely need to care about Output.output or Output.raw at all, with
  4781 some notable exceptions: Output.output is required when bypassing the
  4782 standard channels (writeln etc.), or in token translations to produce
  4783 properly formatted results; Output.raw is required when capturing
  4784 already output material that will eventually be presented to the user
  4785 a second time.  For the default print mode, both Output.output and
  4786 Output.raw have no effect.
  4787 
  4788 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  4789 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  4790 cumulative results are displayed at the end of a batch session.
  4791 
  4792 * Pure/General: File.sysify_path and File.quote_sysify path have been
  4793 replaced by File.platform_path and File.shell_path (with appropriate
  4794 hooks).  This provides a clean interface for unusual systems where the
  4795 internal and external process view of file names are different.
  4796 
  4797 * Pure: more efficient orders for basic syntactic entities: added
  4798 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  4799 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  4800 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  4801 orders now -- potential INCOMPATIBILITY for code that depends on a
  4802 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  4803 Library.sort_strings on result).
  4804 
  4805 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  4806 fold_types traverse types/terms from left to right, observing natural
  4807 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  4808 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  4809 
  4810 * Pure: name spaces have been refined, with significant changes of the
  4811 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  4812 to extern(_table).  The plain name entry path is superceded by a
  4813 general 'naming' context, which also includes the 'policy' to produce
  4814 a fully qualified name and external accesses of a fully qualified
  4815 name; NameSpace.extend is superceded by context dependent
  4816 Sign.declare_name.  Several theory and proof context operations modify
  4817 the naming context.  Especially note Theory.restore_naming and
  4818 ProofContext.restore_naming to get back to a sane state; note that
  4819 Theory.add_path is no longer sufficient to recover from
  4820 Theory.absolute_path in particular.
  4821 
  4822 * Pure: new flags short_names (default false) and unique_names
  4823 (default true) for controlling output of qualified names.  If
  4824 short_names is set, names are printed unqualified.  If unique_names is
  4825 reset, the name prefix is reduced to the minimum required to achieve
  4826 the original result when interning again, even if there is an overlap
  4827 with earlier declarations.
  4828 
  4829 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  4830 now 'extend', and 'merge' gets an additional Pretty.pp argument
  4831 (useful for printing error messages).  INCOMPATIBILITY.
  4832 
  4833 * Pure: major reorganization of the theory context.  Type Sign.sg and
  4834 Theory.theory are now identified, referring to the universal
  4835 Context.theory (see Pure/context.ML).  Actual signature and theory
  4836 content is managed as theory data.  The old code and interfaces were
  4837 spread over many files and structures; the new arrangement introduces
  4838 considerable INCOMPATIBILITY to gain more clarity:
  4839 
  4840   Context -- theory management operations (name, identity, inclusion,
  4841     parents, ancestors, merge, etc.), plus generic theory data;
  4842 
  4843   Sign -- logical signature and syntax operations (declaring consts,
  4844     types, etc.), plus certify/read for common entities;
  4845 
  4846   Theory -- logical theory operations (stating axioms, definitions,
  4847     oracles), plus a copy of logical signature operations (consts,
  4848     types, etc.); also a few basic management operations (Theory.copy,
  4849     Theory.merge, etc.)
  4850 
  4851 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  4852 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  4853 for convenience -- they merely return the theory.
  4854 
  4855 * Pure: type Type.tsig is superceded by theory in most interfaces.
  4856 
  4857 * Pure: the Isar proof context type is already defined early in Pure
  4858 as Context.proof (note that ProofContext.context and Proof.context are
  4859 aliases, where the latter is the preferred name).  This enables other
  4860 Isabelle components to refer to that type even before Isar is present.
  4861 
  4862 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  4863 typeK, constK, axiomK, oracleK), but provide explicit operations for
  4864 any of these kinds.  For example, Sign.intern typeK is now
  4865 Sign.intern_type, Theory.hide_space Sign.typeK is now
  4866 Theory.hide_types.  Also note that former
  4867 Theory.hide_classes/types/consts are now
  4868 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  4869 internalize their arguments!  INCOMPATIBILITY.
  4870 
  4871 * Pure: get_thm interface (of PureThy and ProofContext) expects
  4872 datatype thmref (with constructors Name and NameSelection) instead of
  4873 plain string -- INCOMPATIBILITY;
  4874 
  4875 * Pure: cases produced by proof methods specify options, where NONE
  4876 means to remove case bindings -- INCOMPATIBILITY in
  4877 (RAW_)METHOD_CASES.
  4878 
  4879 * Pure: the following operations retrieve axioms or theorems from a
  4880 theory node or theory hierarchy, respectively:
  4881 
  4882   Theory.axioms_of: theory -> (string * term) list
  4883   Theory.all_axioms_of: theory -> (string * term) list
  4884   PureThy.thms_of: theory -> (string * thm) list
  4885   PureThy.all_thms_of: theory -> (string * thm) list
  4886 
  4887 * Pure: print_tac now outputs the goal through the trace channel.
  4888 
  4889 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  4890 Reference Toplevel.debug (default false) controls detailed printing
  4891 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  4892 controls execution profiling -- set to 1 for time and 2 for space
  4893 (both increase the runtime).
  4894 
  4895 * Isar session: The initial use of ROOT.ML is now always timed,
  4896 i.e. the log will show the actual process times, in contrast to the
  4897 elapsed wall-clock time that the outer shell wrapper produces.
  4898 
  4899 * Simplifier: improved handling of bound variables (nameless
  4900 representation, avoid allocating new strings).  Simprocs that invoke
  4901 the Simplifier recursively should use Simplifier.inherit_bounds to
  4902 avoid local name clashes.  Failure to do so produces warnings
  4903 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  4904 for further details.
  4905 
  4906 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  4907 bindings for all theorems stored within a given theory; this may help
  4908 in porting non-Isar theories to Isar ones, while keeping ML proof
  4909 scripts for the time being.
  4910 
  4911 * ML operator HTML.with_charset specifies the charset begin used for
  4912 generated HTML files.  For example:
  4913 
  4914   HTML.with_charset "utf-8" use_thy "Hebrew";
  4915   HTML.with_charset "utf-8" use_thy "Chinese";
  4916 
  4917 
  4918 *** System ***
  4919 
  4920 * Allow symlinks to all proper Isabelle executables (Isabelle,
  4921 isabelle, isatool etc.).
  4922 
  4923 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  4924 isatool doc, isatool mkdir, display_drafts etc.).
  4925 
  4926 * isatool usedir: option -f allows specification of the ML file to be
  4927 used by Isabelle; default is ROOT.ML.
  4928 
  4929 * New isatool version outputs the version identifier of the Isabelle
  4930 distribution being used.
  4931 
  4932 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  4933 (containing Boolean satisfiability problems) into Isabelle/HOL
  4934 theories.
  4935 
  4936 
  4937 
  4938 New in Isabelle2004 (April 2004)
  4939 --------------------------------
  4940 
  4941 *** General ***
  4942 
  4943 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  4944   Replaces linorder.ML.
  4945 
  4946 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  4947   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  4948   (\<a>...\<z>), are now considered normal letters, and can therefore
  4949   be used anywhere where an ASCII letter (a...zA...Z) has until
  4950   now. COMPATIBILITY: This obviously changes the parsing of some
  4951   terms, especially where a symbol has been used as a binder, say
  4952   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  4953   as an identifier.  Fix it by inserting a space around former
  4954   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  4955   existing theory and ML files.
  4956 
  4957 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  4958 
  4959 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  4960   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  4961   a normal (but invisible) letter. For multiple letter subscripts repeat
  4962   \<^isub> like this: x\<^isub>1\<^isub>2.
  4963 
  4964 * Pure: There are now sub-/superscripts that can span more than one
  4965   character. Text between \<^bsub> and \<^esub> is set in subscript in
  4966   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  4967   superscript. The new control characters are not identifier parts.
  4968 
  4969 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  4970   content of "..." to the latex file instead of \isacntrl... . The "..."
  4971   may consist of any printable characters excluding the end bracket >.
  4972 
  4973 * Pure: Using new Isar command "finalconsts" (or the ML functions
  4974   Theory.add_finals or Theory.add_finals_i) it is now possible to
  4975   declare constants "final", which prevents their being given a definition
  4976   later.  It is useful for constants whose behaviour is fixed axiomatically
  4977   rather than definitionally, such as the meta-logic connectives.
  4978 
  4979 * Pure: 'instance' now handles general arities with general sorts
  4980   (i.e. intersections of classes),
  4981 
  4982 * Presentation: generated HTML now uses a CSS style sheet to make layout
  4983   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  4984   It can be changed to alter the colors/layout of generated pages.
  4985 
  4986 
  4987 *** Isar ***
  4988 
  4989 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  4990   cut_tac, subgoal_tac and thin_tac:
  4991   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  4992     locales are no longer forced to write Isar proof scripts.
  4993     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  4994     emulations.
  4995   - INCOMPATIBILITY: names of variables to be instantiated may no
  4996     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  4997     This is consistent with the instantiation attribute "where".
  4998 
  4999 * Attributes "where" and "of":
  5000   - Now take type variables of instantiated theorem into account when reading
  5001     the instantiation string.  This fixes a bug that caused instantiated
  5002     theorems to have too special types in some circumstances.
  5003   - "where" permits explicit instantiations of type variables.
  5004 
  5005 * Calculation commands "moreover" and "also" no longer interfere with
  5006   current facts ("this"), admitting arbitrary combinations with "then"
  5007   and derived forms.
  5008 
  5009 * Locales:
  5010   - Goal statements involving the context element "includes" no longer
  5011     generate theorems with internal delta predicates (those ending on
  5012     "_axioms") in the premise.
  5013     Resolve particular premise with <locale>.intro to obtain old form.
  5014   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5015     specification and "includes" elements in goal statement.
  5016   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5017     [intro?] and [elim?] (respectively) by default.
  5018   - Experimental command for instantiation of locales in proof contexts:
  5019         instantiate <label>[<attrs>]: <loc>
  5020     Instantiates locale <loc> and adds all its theorems to the current context
  5021     taking into account their attributes.  Label and attrs are optional
  5022     modifiers, like in theorem declarations.  If present, names of
  5023     instantiated theorems are qualified with <label>, and the attributes
  5024     <attrs> are applied after any attributes these theorems might have already.
  5025       If the locale has assumptions, a chained fact of the form
  5026     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5027     are derived.  The command does not support old-style locales declared
  5028     with "locale (open)".
  5029       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5030 
  5031 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5032   (Isar) contexts.
  5033 
  5034 
  5035 *** HOL ***
  5036 
  5037 * Proof import: new image HOL4 contains the imported library from
  5038   the HOL4 system with about 2500 theorems. It is imported by
  5039   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5040   can be used like any other Isabelle image.  See
  5041   HOL/Import/HOL/README for more information.
  5042 
  5043 * Simplifier:
  5044   - Much improved handling of linear and partial orders.
  5045     Reasoners for linear and partial orders are set up for type classes
  5046     "linorder" and "order" respectively, and are added to the default simpset
  5047     as solvers.  This means that the simplifier can build transitivity chains
  5048     to solve goals from the assumptions.
  5049   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5050     of blast or auto after simplification become unnecessary because the goal
  5051     is solved by simplification already.
  5052 
  5053 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5054     all proved in axiomatic type classes for semirings, rings and fields.
  5055 
  5056 * Numerics:
  5057   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5058     now formalized using the Ring_and_Field theory mentioned above.
  5059   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5060     than before, because now they are set up once in a generic manner.
  5061   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5062     Look for the general versions in Ring_and_Field (and Power if they concern
  5063     exponentiation).
  5064 
  5065 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5066 
  5067 * Records:
  5068   - Record types are now by default printed with their type abbreviation
  5069     instead of the list of all field types. This can be configured via
  5070     the reference "print_record_type_abbr".
  5071   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5072     (not enabled by default).
  5073   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5074     EX x. x = sel r to True (not enabled by default).
  5075   - Tactic "record_split_simp_tac" to split and simplify records added.
  5076 
  5077 * 'specification' command added, allowing for definition by
  5078   specification.  There is also an 'ax_specification' command that
  5079   introduces the new constants axiomatically.
  5080 
  5081 * arith(_tac) is now able to generate counterexamples for reals as well.
  5082 
  5083 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5084 
  5085 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5086   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5087 
  5088 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5089   matrix theory to linear programming.
  5090 
  5091 * Unions and Intersections:
  5092   The latex output syntax of UN and INT has been changed
  5093   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5094   i.e. the index formulae has become a subscript.
  5095   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5096 
  5097 * Unions and Intersections over Intervals:
  5098   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5099   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5100   like in normal math, and corresponding versions for < and for intersection.
  5101 
  5102 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5103   lexicographic dictonary ordering has been added as "lexord".
  5104 
  5105 * ML: the legacy theory structures Int and List have been removed. They had
  5106   conflicted with ML Basis Library structures having the same names.
  5107 
  5108 * 'refute' command added to search for (finite) countermodels.  Only works
  5109   for a fragment of HOL.  The installation of an external SAT solver is
  5110   highly recommended.  See "HOL/Refute.thy" for details.
  5111 
  5112 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5113   formulae under an assignment of free variables to random values.
  5114   In contrast to 'refute', it can deal with inductive datatypes,
  5115   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5116   for examples.
  5117 
  5118 
  5119 *** HOLCF ***
  5120 
  5121 * Streams now come with concatenation and are part of the HOLCF image
  5122 
  5123 
  5124 
  5125 New in Isabelle2003 (May 2003)
  5126 ------------------------------
  5127 
  5128 *** General ***
  5129 
  5130 * Provers/simplifier:
  5131 
  5132   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5133     Assumptions are now subject to complete mutual simplification,
  5134     not just from left to right. The simplifier now preserves
  5135     the order of assumptions.
  5136 
  5137     Potential INCOMPATIBILITY:
  5138 
  5139     -- simp sometimes diverges where the old version did
  5140        not, e.g. invoking simp on the goal
  5141 
  5142         [| P (f x); y = x; f x = f y |] ==> Q
  5143 
  5144        now gives rise to the infinite reduction sequence
  5145 
  5146         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5147 
  5148        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5149        kind of problem.
  5150 
  5151     -- Tactics combining classical reasoner and simplification (such as auto)
  5152        are also affected by this change, because many of them rely on
  5153        simp. They may sometimes diverge as well or yield a different numbers
  5154        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5155        in case of problems. Sometimes subsequent calls to the classical
  5156        reasoner will fail because a preceeding call to the simplifier too
  5157        eagerly simplified the goal, e.g. deleted redundant premises.
  5158 
  5159   - The simplifier trace now shows the names of the applied rewrite rules
  5160 
  5161   - You can limit the number of recursive invocations of the simplifier
  5162     during conditional rewriting (where the simplifie tries to solve the
  5163     conditions before applying the rewrite rule):
  5164     ML "simp_depth_limit := n"
  5165     where n is an integer. Thus you can force termination where previously
  5166     the simplifier would diverge.
  5167 
  5168   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5169 
  5170   - No longer aborts on failed congruence proof.  Instead, the
  5171     congruence is ignored.
  5172 
  5173 * Pure: New generic framework for extracting programs from constructive
  5174   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5175   as HOL/Extraction for some case studies.
  5176 
  5177 * Pure: The main goal of the proof state is no longer shown by default, only
  5178 the subgoals. This behaviour is controlled by a new flag.
  5179    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5180 (ML: Proof.show_main_goal).
  5181 
  5182 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5183 rules whose conclusion matches subgoal 1:
  5184       PG menu: Isabelle/Isar -> Show me -> matching rules
  5185 The rules are ordered by how closely they match the subgoal.
  5186 In particular, rules that solve a subgoal outright are displayed first
  5187 (or rather last, the way they are printed).
  5188 (ML: ProofGeneral.print_intros())
  5189 
  5190 * Pure: New flag trace_unify_fail causes unification to print
  5191 diagnostic information (PG: in trace buffer) when it fails. This is
  5192 useful for figuring out why single step proofs like rule, erule or
  5193 assumption failed.
  5194 
  5195 * Pure: Locale specifications now produce predicate definitions
  5196 according to the body of text (covering assumptions modulo local
  5197 definitions); predicate "loc_axioms" covers newly introduced text,
  5198 while "loc" is cumulative wrt. all included locale expressions; the
  5199 latter view is presented only on export into the global theory
  5200 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5201 on the old view without predicates;
  5202 
  5203 * Pure: predefined locales "var" and "struct" are useful for sharing
  5204 parameters (as in CASL, for example); just specify something like
  5205 ``var x + var y + struct M'' as import;
  5206 
  5207 * Pure: improved thms_containing: proper indexing of facts instead of
  5208 raw theorems; check validity of results wrt. current name space;
  5209 include local facts of proof configuration (also covers active
  5210 locales), cover fixed variables in index; may use "_" in term
  5211 specification; an optional limit for the number of printed facts may
  5212 be given (the default is 40);
  5213 
  5214 * Pure: disallow duplicate fact bindings within new-style theory files
  5215 (batch-mode only);
  5216 
  5217 * Provers: improved induct method: assumptions introduced by case
  5218 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5219 the goal statement); "foo" still refers to all facts collectively;
  5220 
  5221 * Provers: the function blast.overloaded has been removed: all constants
  5222 are regarded as potentially overloaded, which improves robustness in exchange
  5223 for slight decrease in efficiency;
  5224 
  5225 * Provers/linorder: New generic prover for transitivity reasoning over
  5226 linear orders.  Note: this prover is not efficient!
  5227 
  5228 * Isar: preview of problems to finish 'show' now produce an error
  5229 rather than just a warning (in interactive mode);
  5230 
  5231 
  5232 *** HOL ***
  5233 
  5234 * arith(_tac)
  5235 
  5236  - Produces a counter example if it cannot prove a goal.
  5237    Note that the counter example may be spurious if the goal is not a formula
  5238    of quantifier-free linear arithmetic.
  5239    In ProofGeneral the counter example appears in the trace buffer.
  5240 
  5241  - Knows about div k and mod k where k is a numeral of type nat or int.
  5242 
  5243  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5244    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5245    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5246 
  5247 * simp's arithmetic capabilities have been enhanced a bit: it now
  5248 takes ~= in premises into account (by performing a case split);
  5249 
  5250 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5251 are distributed over a sum of terms;
  5252 
  5253 * New tactic "trans_tac" and method "trans" instantiate
  5254 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5255 "<=", "<" and "=").
  5256 
  5257 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5258 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5259 
  5260 * 'typedef' command has new option "open" to suppress the set
  5261 definition;
  5262 
  5263 * functions Min and Max on finite sets have been introduced (theory
  5264 Finite_Set);
  5265 
  5266 * attribute [symmetric] now works for relations as well; it turns
  5267 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5268 
  5269 * induct over a !!-quantified statement (say !!x1..xn):
  5270   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5271 
  5272 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5273 %x. None. Warning: empty_def now refers to the previously hidden definition
  5274 of the empty set.
  5275 
  5276 * Algebra: formalization of classical algebra.  Intended as base for
  5277 any algebraic development in Isabelle.  Currently covers group theory
  5278 (up to Sylow's theorem) and ring theory (Universal Property of
  5279 Univariate Polynomials).  Contributions welcome;
  5280 
  5281 * GroupTheory: deleted, since its material has been moved to Algebra;
  5282 
  5283 * Complex: new directory of the complex numbers with numeric constants,
  5284 nonstandard complex numbers, and some complex analysis, standard and
  5285 nonstandard (Jacques Fleuriot);
  5286 
  5287 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  5288 
  5289 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  5290 Fleuriot);
  5291 
  5292 * Real/HahnBanach: updated and adapted to locales;
  5293 
  5294 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  5295 Gray and Kramer);
  5296 
  5297 * UNITY: added the Meier-Sanders theory of progress sets;
  5298 
  5299 * MicroJava: bytecode verifier and lightweight bytecode verifier
  5300 as abstract algorithms, instantiated to the JVM;
  5301 
  5302 * Bali: Java source language formalization. Type system, operational
  5303 semantics, axiomatic semantics. Supported language features:
  5304 classes, interfaces, objects,virtual methods, static methods,
  5305 static/instance fields, arrays, access modifiers, definite
  5306 assignment, exceptions.
  5307 
  5308 
  5309 *** ZF ***
  5310 
  5311 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  5312 universe, etc.);
  5313 
  5314 * Main ZF: virtually all theories converted to new-style format;
  5315 
  5316 
  5317 *** ML ***
  5318 
  5319 * Pure: Tactic.prove provides sane interface for internal proofs;
  5320 omits the infamous "standard" operation, so this is more appropriate
  5321 than prove_goalw_cterm in many situations (e.g. in simprocs);
  5322 
  5323 * Pure: improved error reporting of simprocs;
  5324 
  5325 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  5326 up simprocs;
  5327 
  5328 
  5329 *** Document preparation ***
  5330 
  5331 * uses \par instead of \\ for line breaks in theory text. This may
  5332 shift some page breaks in large documents. To get the old behaviour
  5333 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  5334 
  5335 * minimized dependencies of isabelle.sty and isabellesym.sty on
  5336 other packages
  5337 
  5338 * \<euro> now needs package babel/greek instead of marvosym (which
  5339 broke \Rightarrow)
  5340 
  5341 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  5342 textcomp package)
  5343 
  5344 
  5345 
  5346 New in Isabelle2002 (March 2002)
  5347 --------------------------------
  5348 
  5349 *** Document preparation ***
  5350 
  5351 * greatly simplified document preparation setup, including more
  5352 graceful interpretation of isatool usedir -i/-d/-D options, and more
  5353 instructive isatool mkdir; users should basically be able to get
  5354 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  5355 users may run a separate document processing stage manually like this:
  5356 "isatool usedir -D output HOL Test && isatool document Test/output";
  5357 
  5358 * theory dependency graph may now be incorporated into documents;
  5359 isatool usedir -g true will produce session_graph.eps/.pdf for use
  5360 with \includegraphics of LaTeX;
  5361 
  5362 * proper spacing of consecutive markup elements, especially text
  5363 blocks after section headings;
  5364 
  5365 * support bold style (for single symbols only), input syntax is like
  5366 this: "\<^bold>\<alpha>" or "\<^bold>A";
  5367 
  5368 * \<bullet> is now output as bold \cdot by default, which looks much
  5369 better in printed text;
  5370 
  5371 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  5372 note that these symbols are currently unavailable in Proof General /
  5373 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  5374 
  5375 * isatool latex no longer depends on changed TEXINPUTS, instead
  5376 isatool document copies the Isabelle style files to the target
  5377 location;
  5378 
  5379 
  5380 *** Isar ***
  5381 
  5382 * Pure/Provers: improved proof by cases and induction;
  5383   - 'case' command admits impromptu naming of parameters (such as
  5384     "case (Suc n)");
  5385   - 'induct' method divinates rule instantiation from the inductive
  5386     claim; no longer requires excessive ?P bindings for proper
  5387     instantiation of cases;
  5388   - 'induct' method properly enumerates all possibilities of set/type
  5389     rules; as a consequence facts may be also passed through *type*
  5390     rules without further ado;
  5391   - 'induct' method now derives symbolic cases from the *rulified*
  5392     rule (before it used to rulify cases stemming from the internal
  5393     atomized version); this means that the context of a non-atomic
  5394     statement becomes is included in the hypothesis, avoiding the
  5395     slightly cumbersome show "PROP ?case" form;
  5396   - 'induct' may now use elim-style induction rules without chaining
  5397     facts, using ``missing'' premises from the goal state; this allows
  5398     rules stemming from inductive sets to be applied in unstructured
  5399     scripts, while still benefitting from proper handling of non-atomic
  5400     statements; NB: major inductive premises need to be put first, all
  5401     the rest of the goal is passed through the induction;
  5402   - 'induct' proper support for mutual induction involving non-atomic
  5403     rule statements (uses the new concept of simultaneous goals, see
  5404     below);
  5405   - append all possible rule selections, but only use the first
  5406     success (no backtracking);
  5407   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  5408   - undeclared rule case names default to numbers 1, 2, 3, ...;
  5409   - added 'print_induct_rules' (covered by help item in recent Proof
  5410     General versions);
  5411   - moved induct/cases attributes to Pure, methods to Provers;
  5412   - generic method setup instantiated for FOL and HOL;
  5413 
  5414 * Pure: support multiple simultaneous goal statements, for example
  5415 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  5416 meta-level mechanism, this acts as if several individual goals had
  5417 been stated separately; in particular common proof methods need to be
  5418 repeated in order to cover all claims; note that a single elimination
  5419 step is *not* sufficient to establish the two conjunctions, so this
  5420 fails:
  5421 
  5422   assume "A & B" then have A and B ..   (*".." fails*)
  5423 
  5424 better use "obtain" in situations as above; alternative refer to
  5425 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  5426 
  5427 * Pure: proper integration with ``locales''; unlike the original
  5428 version by Florian Kammller, Isar locales package high-level proof
  5429 contexts rather than raw logical ones (e.g. we admit to include
  5430 attributes everywhere); operations on locales include merge and
  5431 rename; support for implicit arguments (``structures''); simultaneous
  5432 type-inference over imports and text; see also HOL/ex/Locales.thy for
  5433 some examples;
  5434 
  5435 * Pure: the following commands have been ``localized'', supporting a
  5436 target locale specification "(in name)": 'lemma', 'theorem',
  5437 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  5438 stored both within the locale and at the theory level (exported and
  5439 qualified by the locale name);
  5440 
  5441 * Pure: theory goals may now be specified in ``long'' form, with
  5442 ad-hoc contexts consisting of arbitrary locale elements. for example
  5443 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  5444 definitions may be given, too); the result is a meta-level rule with
  5445 the context elements being discharged in the obvious way;
  5446 
  5447 * Pure: new proof command 'using' allows to augment currently used
  5448 facts after a goal statement ('using' is syntactically analogous to
  5449 'apply', but acts on the goal's facts only); this allows chained facts
  5450 to be separated into parts given before and after a claim, as in
  5451 ``from a and b have C using d and e <proof>'';
  5452 
  5453 * Pure: renamed "antecedent" case to "rule_context";
  5454 
  5455 * Pure: new 'judgment' command records explicit information about the
  5456 object-logic embedding (used by several tools internally); no longer
  5457 use hard-wired "Trueprop";
  5458 
  5459 * Pure: added 'corollary' command;
  5460 
  5461 * Pure: fixed 'token_translation' command;
  5462 
  5463 * Pure: removed obsolete 'exported' attribute;
  5464 
  5465 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  5466 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  5467 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  5468 
  5469 * Pure: method 'atomize' presents local goal premises as object-level
  5470 statements (atomic meta-level propositions); setup controlled via
  5471 rewrite rules declarations of 'atomize' attribute; example
  5472 application: 'induct' method with proper rule statements in improper
  5473 proof *scripts*;
  5474 
  5475 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  5476 now consider the syntactic context of assumptions, giving a better
  5477 chance to get type-inference of the arguments right (this is
  5478 especially important for locales);
  5479 
  5480 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  5481 mode;
  5482 
  5483 * Pure/obtain: the formal conclusion "thesis", being marked as
  5484 ``internal'', may no longer be reference directly in the text;
  5485 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  5486 situations;
  5487 
  5488 * Pure: generic 'sym' attribute which declares a rule both as pure
  5489 'elim?' and for the 'symmetric' operation;
  5490 
  5491 * Pure: marginal comments ``--'' may now occur just anywhere in the
  5492 text; the fixed correlation with particular command syntax has been
  5493 discontinued;
  5494 
  5495 * Pure: new method 'rules' is particularly well-suited for proof
  5496 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  5497 but often produces more compact proof terms with less detours;
  5498 
  5499 * Pure/Provers/classical: simplified integration with pure rule
  5500 attributes and methods; the classical "intro?/elim?/dest?"
  5501 declarations coincide with the pure ones; the "rule" method no longer
  5502 includes classically swapped intros; "intro" and "elim" methods no
  5503 longer pick rules from the context; also got rid of ML declarations
  5504 AddXIs/AddXEs/AddXDs; all of this has some potential for
  5505 INCOMPATIBILITY;
  5506 
  5507 * Provers/classical: attribute 'swapped' produces classical inversions
  5508 of introduction rules;
  5509 
  5510 * Provers/simplifier: 'simplified' attribute may refer to explicit
  5511 rules instead of full simplifier context; 'iff' attribute handles
  5512 conditional rules;
  5513 
  5514 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  5515 
  5516 * HOL: 'recdef' now fails on unfinished automated proofs, use
  5517 "(permissive)" option to recover old behavior;
  5518 
  5519 * HOL: 'inductive' no longer features separate (collective) attributes
  5520 for 'intros' (was found too confusing);
  5521 
  5522 * HOL: properly declared induction rules less_induct and
  5523 wf_induct_rule;
  5524 
  5525 
  5526 *** HOL ***
  5527 
  5528 * HOL: moved over to sane numeral syntax; the new policy is as
  5529 follows:
  5530 
  5531   - 0 and 1 are polymorphic constants, which are defined on any
  5532   numeric type (nat, int, real etc.);
  5533 
  5534   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  5535   binary representation internally;
  5536 
  5537   - type nat has special constructor Suc, and generally prefers Suc 0
  5538   over 1::nat and Suc (Suc 0) over 2::nat;
  5539 
  5540 This change may cause significant problems of INCOMPATIBILITY; here
  5541 are some hints on converting existing sources:
  5542 
  5543   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  5544   entities, so expressions involving "-" (unary or binary minus) need
  5545   to be spaced properly;
  5546 
  5547   - existing occurrences of "1" may need to be constraint "1::nat" or
  5548   even replaced by Suc 0; similar for old "2";
  5549 
  5550   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  5551 
  5552   - remove all special provisions on numerals in proofs;
  5553 
  5554 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  5555 representation (depends on bin_arith_simps in the default context);
  5556 
  5557 * HOL: symbolic syntax for x^2 (numeral 2);
  5558 
  5559 * HOL: the class of all HOL types is now called "type" rather than
  5560 "term"; INCOMPATIBILITY, need to adapt references to this type class
  5561 in axclass/classes, instance/arities, and (usually rare) occurrences
  5562 in typings (of consts etc.); internally the class is called
  5563 "HOL.type", ML programs should refer to HOLogic.typeS;
  5564 
  5565 * HOL/record package improvements:
  5566   - new derived operations "fields" to build a partial record section,
  5567     "extend" to promote a fixed record to a record scheme, and
  5568     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  5569     declared as simp by default;
  5570   - shared operations ("more", "fields", etc.) now need to be always
  5571     qualified) --- potential INCOMPATIBILITY;
  5572   - removed "make_scheme" operations (use "make" with "extend") --
  5573     INCOMPATIBILITY;
  5574   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  5575   - provides cases/induct rules for use with corresponding Isar
  5576     methods (for concrete records, record schemes, concrete more
  5577     parts, and schematic more parts -- in that order);
  5578   - internal definitions directly based on a light-weight abstract
  5579     theory of product types over typedef rather than datatype;
  5580 
  5581 * HOL: generic code generator for generating executable ML code from
  5582 specifications; specific support for HOL constructs such as inductive
  5583 datatypes and sets, as well as recursive functions; can be invoked
  5584 via 'generate_code' theory section;
  5585 
  5586 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  5587 
  5588 * HOL: consolidated and renamed several theories.  In particular:
  5589         Ord.thy has been absorbed into HOL.thy
  5590         String.thy has been absorbed into List.thy
  5591 
  5592 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  5593 (beware of argument permutation!);
  5594 
  5595 * HOL: linorder_less_split superseded by linorder_cases;
  5596 
  5597 * HOL/List: "nodups" renamed to "distinct";
  5598 
  5599 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  5600 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  5601   - Ex_def has changed, now need to use some_eq_ex
  5602 
  5603 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  5604 in this (rare) case use:
  5605 
  5606   delSWrapper "split_all_tac"
  5607   addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
  5608 
  5609 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
  5610 MAY FAIL;
  5611 
  5612 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
  5613 Isabelle's type classes, ^ on functions and relations has too general
  5614 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be
  5615 necessary to attach explicit type constraints;
  5616 
  5617 * HOL/Relation: the prefix name of the infix "O" has been changed from
  5618 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been
  5619 renamed accordingly (eg "compI" -> "rel_compI").
  5620 
  5621 * HOL: syntax translations now work properly with numerals and records
  5622 expressions;
  5623 
  5624 * HOL: bounded abstraction now uses syntax "%" / "\<lambda>" instead
  5625 of "lam" -- INCOMPATIBILITY;
  5626 
  5627 * HOL: got rid of some global declarations (potential INCOMPATIBILITY
  5628 for ML tools): const "()" renamed "Product_Type.Unity", type "unit"
  5629 renamed "Product_Type.unit";
  5630 
  5631 * HOL: renamed rtrancl_into_rtrancl2 to converse_rtrancl_into_rtrancl
  5632 
  5633 * HOL: removed obsolete theorem "optionE" (use "option.exhaust", or
  5634 the "cases" method);
  5635 
  5636 * HOL/GroupTheory: group theory examples including Sylow's theorem (by
  5637 Florian Kammller);
  5638 
  5639 * HOL/IMP: updated and converted to new-style theory format; several
  5640 parts turned into readable document, with proper Isar proof texts and
  5641 some explanations (by Gerwin Klein);
  5642 
  5643 * HOL-Real: added Complex_Numbers (by Gertrud Bauer);
  5644 
  5645 * HOL-Hyperreal is now a logic image;
  5646 
  5647 
  5648 *** HOLCF ***
  5649 
  5650 * Isar: consts/constdefs supports mixfix syntax for continuous
  5651 operations;
  5652 
  5653 * Isar: domain package adapted to new-style theory format, e.g. see
  5654 HOLCF/ex/Dnat.thy;
  5655 
  5656 * theory Lift: proper use of rep_datatype lift instead of ML hacks --
  5657 potential INCOMPATIBILITY; now use plain induct_tac instead of former
  5658 lift.induct_tac, always use UU instead of Undef;
  5659 
  5660 * HOLCF/IMP: updated and converted to new-style theory;
  5661 
  5662 
  5663 *** ZF ***
  5664 
  5665 * Isar: proper integration of logic-specific tools and packages,
  5666 including theory commands '(co)inductive', '(co)datatype',
  5667 'rep_datatype', 'inductive_cases', as well as methods 'ind_cases',
  5668 'induct_tac', 'case_tac', and 'typecheck' (with attribute 'TC');
  5669 
  5670 * theory Main no longer includes AC; for the Axiom of Choice, base
  5671 your theory on Main_ZFC;
  5672 
  5673 * the integer library now covers quotients and remainders, with many
  5674 laws relating division to addition, multiplication, etc.;
  5675 
  5676 * ZF/UNITY: Chandy and Misra's UNITY is now available in ZF, giving a
  5677 typeless version of the formalism;
  5678 
  5679 * ZF/AC, Coind, IMP, Resid: updated and converted to new-style theory
  5680 format;
  5681 
  5682 * ZF/Induct: new directory for examples of inductive definitions,
  5683 including theory Multiset for multiset orderings; converted to
  5684 new-style theory format;
  5685 
  5686 * ZF: many new theorems about lists, ordinals, etc.;
  5687 
  5688 
  5689 *** General ***
  5690 
  5691 * Pure/kernel: meta-level proof terms (by Stefan Berghofer); reference
  5692 variable proof controls level of detail: 0 = no proofs (only oracle
  5693 dependencies), 1 = lemma dependencies, 2 = compact proof terms; see
  5694 also ref manual for further ML interfaces;
  5695 
  5696 * Pure/axclass: removed obsolete ML interface
  5697 goal_subclass/goal_arity;
  5698 
  5699 * Pure/syntax: new token syntax "num" for plain numerals (without "#"
  5700 of "xnum"); potential INCOMPATIBILITY, since -0, -1 etc. are now
  5701 separate tokens, so expressions involving minus need to be spaced
  5702 properly;
  5703 
  5704 * Pure/syntax: support non-oriented infixes, using keyword "infix"
  5705 rather than "infixl" or "infixr";
  5706 
  5707 * Pure/syntax: concrete syntax for dummy type variables admits genuine
  5708 sort constraint specifications in type inference; e.g. "x::_::foo"
  5709 ensures that the type of "x" is of sort "foo" (but not necessarily a
  5710 type variable);
  5711 
  5712 * Pure/syntax: print modes "type_brackets" and "no_type_brackets"
  5713 control output of nested => (types); the default behavior is
  5714 "type_brackets";
  5715 
  5716 * Pure/syntax: builtin parse translation for "_constify" turns valued
  5717 tokens into AST constants;
  5718 
  5719 * Pure/syntax: prefer later declarations of translations and print
  5720 translation functions; potential INCOMPATIBILITY: need to reverse
  5721 multiple declarations for same syntax element constant;
  5722 
  5723 * Pure/show_hyps reset by default (in accordance to existing Isar
  5724 practice);
  5725 
  5726 * Provers/classical: renamed addaltern to addafter, addSaltern to
  5727 addSafter;
  5728 
  5729 * Provers/clasimp: ``iff'' declarations now handle conditional rules
  5730 as well;
  5731 
  5732 * system: tested support for MacOS X; should be able to get Isabelle +
  5733 Proof General to work in a plain Terminal after installing Poly/ML
  5734 (e.g. from the Isabelle distribution area) and GNU bash alone
  5735 (e.g. from http://www.apple.com); full X11, XEmacs and X-Symbol
  5736 support requires further installations, e.g. from
  5737 http://fink.sourceforge.net/);
  5738 
  5739 * system: support Poly/ML 4.1.1 (able to manage larger heaps);
  5740 
  5741 * system: reduced base memory usage by Poly/ML (approx. 20 MB instead
  5742 of 40 MB), cf. ML_OPTIONS;
  5743 
  5744 * system: Proof General keywords specification is now part of the
  5745 Isabelle distribution (see etc/isar-keywords.el);
  5746 
  5747 * system: support for persistent Proof General sessions (refrain from
  5748 outdating all loaded theories on startup); user may create writable
  5749 logic images like this: ``isabelle -q HOL Test'';
  5750 
  5751 * system: smart selection of Isabelle process versus Isabelle
  5752 interface, accommodates case-insensitive file systems (e.g. HFS+); may
  5753 run both "isabelle" and "Isabelle" even if file names are badly
  5754 damaged (executable inspects the case of the first letter of its own
  5755 name); added separate "isabelle-process" and "isabelle-interface";
  5756 
  5757 * system: refrain from any attempt at filtering input streams; no
  5758 longer support ``8bit'' encoding of old isabelle font, instead proper
  5759 iso-latin characters may now be used; the related isatools
  5760 "symbolinput" and "nonascii" have disappeared as well;
  5761 
  5762 * system: removed old "xterm" interface (the print modes "xterm" and
  5763 "xterm_color" are still available for direct use in a suitable
  5764 terminal);
  5765 
  5766 
  5767 
  5768 New in Isabelle99-2 (February 2001)
  5769 -----------------------------------
  5770 
  5771 *** Overview of INCOMPATIBILITIES ***
  5772 
  5773 * HOL: please note that theories in the Library and elsewhere often use the
  5774 new-style (Isar) format; to refer to their theorems in an ML script you must
  5775 bind them to ML identifers by e.g.      val thm_name = thm "thm_name";
  5776 
  5777 * HOL: inductive package no longer splits induction rule aggressively,
  5778 but only as far as specified by the introductions given; the old
  5779 format may be recovered via ML function complete_split_rule or attribute
  5780 'split_rule (complete)';
  5781 
  5782 * HOL: induct renamed to lfp_induct, lfp_Tarski to lfp_unfold,
  5783 gfp_Tarski to gfp_unfold;
  5784 
  5785 * HOL: contrapos, contrapos2 renamed to contrapos_nn, contrapos_pp;
  5786 
  5787 * HOL: infix "dvd" now has priority 50 rather than 70 (because it is a
  5788 relation); infix "^^" has been renamed "``"; infix "``" has been
  5789 renamed "`"; "univalent" has been renamed "single_valued";
  5790 
  5791 * HOL/Real: "rinv" and "hrinv" replaced by overloaded "inverse"
  5792 operation;
  5793 
  5794 * HOLCF: infix "`" has been renamed "$"; the symbol syntax is \<cdot>;
  5795 
  5796 * Isar: 'obtain' no longer declares "that" fact as simp/intro;
  5797 
  5798 * Isar/HOL: method 'induct' now handles non-atomic goals; as a
  5799 consequence, it is no longer monotonic wrt. the local goal context
  5800 (which is now passed through the inductive cases);
  5801 
  5802 * Document preparation: renamed standard symbols \<ll> to \<lless> and
  5803 \<gg> to \<ggreater>;
  5804 
  5805 
  5806 *** Document preparation ***
  5807 
  5808 * \isabellestyle{NAME} selects version of Isabelle output (currently
  5809 available: are "it" for near math-mode best-style output, "sl" for
  5810 slanted text style, and "tt" for plain type-writer; if no
  5811 \isabellestyle command is given, output is according to slanted
  5812 type-writer);
  5813 
  5814 * support sub/super scripts (for single symbols only), input syntax is
  5815 like this: "A\<^sup>*" or "A\<^sup>\<star>";
  5816 
  5817 * some more standard symbols; see Appendix A of the system manual for
  5818 the complete list of symbols defined in isabellesym.sty;
  5819 
  5820 * improved isabelle style files; more abstract symbol implementation
  5821 (should now use \isamath{...} and \isatext{...} in custom symbol
  5822 definitions);
  5823 
  5824 * antiquotation @{goals} and @{subgoals} for output of *dynamic* goals
  5825 state; Note that presentation of goal states does not conform to
  5826 actual human-readable proof documents.  Please do not include goal
  5827 states into document output unless you really know what you are doing!
  5828 
  5829 * proper indentation of antiquoted output with proportional LaTeX
  5830 fonts;
  5831 
  5832 * no_document ML operator temporarily disables LaTeX document
  5833 generation;
  5834 
  5835 * isatool unsymbolize tunes sources for plain ASCII communication;
  5836 
  5837 
  5838 *** Isar ***
  5839 
  5840 * Pure: Isar now suffers initial goal statements to contain unbound
  5841 schematic variables (this does not conform to actual readable proof
  5842 documents, due to unpredictable outcome and non-compositional proof
  5843 checking); users who know what they are doing may use schematic goals
  5844 for Prolog-style synthesis of proven results;
  5845 
  5846 * Pure: assumption method (an implicit finishing) now handles actual
  5847 rules as well;
  5848 
  5849 * Pure: improved 'obtain' --- moved to Pure, insert "that" into
  5850 initial goal, declare "that" only as Pure intro (only for single
  5851 steps); the "that" rule assumption may now be involved in implicit
  5852 finishing, thus ".." becomes a feasible for trivial obtains;
  5853 
  5854 * Pure: default proof step now includes 'intro_classes'; thus trivial
  5855 instance proofs may be performed by "..";
  5856 
  5857 * Pure: ?thesis / ?this / "..." now work for pure meta-level
  5858 statements as well;
  5859 
  5860 * Pure: more robust selection of calculational rules;
  5861 
  5862 * Pure: the builtin notion of 'finished' goal now includes the ==-refl
  5863 rule (as well as the assumption rule);
  5864 
  5865 * Pure: 'thm_deps' command visualizes dependencies of theorems and
  5866 lemmas, using the graph browser tool;
  5867 
  5868 * Pure: predict failure of "show" in interactive mode;
  5869 
  5870 * Pure: 'thms_containing' now takes actual terms as arguments;
  5871 
  5872 * HOL: improved method 'induct' --- now handles non-atomic goals
  5873 (potential INCOMPATIBILITY); tuned error handling;
  5874 
  5875 * HOL: cases and induct rules now provide explicit hints about the
  5876 number of facts to be consumed (0 for "type" and 1 for "set" rules);
  5877 any remaining facts are inserted into the goal verbatim;
  5878 
  5879 * HOL: local contexts (aka cases) may now contain term bindings as
  5880 well; the 'cases' and 'induct' methods new provide a ?case binding for
  5881 the result to be shown in each case;
  5882 
  5883 * HOL: added 'recdef_tc' command;
  5884 
  5885 * isatool convert assists in eliminating legacy ML scripts;
  5886 
  5887 
  5888 *** HOL ***
  5889 
  5890 * HOL/Library: a collection of generic theories to be used together
  5891 with main HOL; the theory loader path already includes this directory
  5892 by default; the following existing theories have been moved here:
  5893 HOL/Induct/Multiset, HOL/Induct/Acc (as Accessible_Part), HOL/While
  5894 (as While_Combinator), HOL/Lex/Prefix (as List_Prefix);
  5895 
  5896 * HOL/Unix: "Some aspects of Unix file-system security", a typical
  5897 modelling and verification task performed in Isabelle/HOL +
  5898 Isabelle/Isar + Isabelle document preparation (by Markus Wenzel).
  5899 
  5900 * HOL/Algebra: special summation operator SUM no longer exists, it has
  5901 been replaced by setsum; infix 'assoc' now has priority 50 (like
  5902 'dvd'); axiom 'one_not_zero' has been moved from axclass 'ring' to
  5903 'domain', this makes the theory consistent with mathematical
  5904 literature;
  5905 
  5906 * HOL basics: added overloaded operations "inverse" and "divide"
  5907 (infix "/"), syntax for generic "abs" operation, generic summation
  5908 operator \<Sum>;
  5909 
  5910 * HOL/typedef: simplified package, provide more useful rules (see also
  5911 HOL/subset.thy);
  5912 
  5913 * HOL/datatype: induction rule for arbitrarily branching datatypes is
  5914 now expressed as a proper nested rule (old-style tactic scripts may
  5915 require atomize_strip_tac to cope with non-atomic premises);
  5916 
  5917 * HOL: renamed theory "Prod" to "Product_Type", renamed "split" rule
  5918 to "split_conv" (old name still available for compatibility);
  5919 
  5920 * HOL: improved concrete syntax for strings (e.g. allows translation
  5921 rules with string literals);
  5922 
  5923 * HOL-Real-Hyperreal: this extends HOL-Real with the hyperreals
  5924  and Fleuriot's mechanization of analysis, including the transcendental
  5925  functions for the reals;
  5926 
  5927 * HOL/Real, HOL/Hyperreal: improved arithmetic simplification;
  5928 
  5929 
  5930 *** CTT ***
  5931 
  5932 * CTT: x-symbol support for Pi, Sigma, -->, : (membership); note that
  5933 "lam" is displayed as TWO lambda-symbols
  5934 
  5935 * CTT: theory Main now available, containing everything (that is, Bool
  5936 and Arith);
  5937 
  5938 
  5939 *** General ***
  5940 
  5941 * Pure: the Simplifier has been implemented properly as a derived rule
  5942 outside of the actual kernel (at last!); the overall performance
  5943 penalty in practical applications is about 50%, while reliability of
  5944 the Isabelle inference kernel has been greatly improved;
  5945 
  5946 * print modes "brackets" and "no_brackets" control output of nested =>
  5947 (types) and ==> (props); the default behaviour is "brackets";
  5948 
  5949 * Provers: fast_tac (and friends) now handle actual object-logic rules
  5950 as assumptions as well;
  5951 
  5952 * system: support Poly/ML 4.0;
  5953 
  5954 * system: isatool install handles KDE version 1 or 2;
  5955 
  5956 
  5957 
  5958 New in Isabelle99-1 (October 2000)
  5959 ----------------------------------
  5960 
  5961 *** Overview of INCOMPATIBILITIES ***
  5962 
  5963 * HOL: simplification of natural numbers is much changed; to partly
  5964 recover the old behaviour (e.g. to prevent n+n rewriting to #2*n)
  5965 issue the following ML commands:
  5966 
  5967   Delsimprocs Nat_Numeral_Simprocs.cancel_numerals;
  5968   Delsimprocs [Nat_Numeral_Simprocs.combine_numerals];
  5969 
  5970 * HOL: simplification no longer dives into case-expressions; this is
  5971 controlled by "t.weak_case_cong" for each datatype t;
  5972 
  5973 * HOL: nat_less_induct renamed to less_induct;
  5974 
  5975 * HOL: systematic renaming of the SOME (Eps) rules, may use isatool
  5976 fixsome to patch .thy and .ML sources automatically;
  5977 
  5978   select_equality  -> some_equality
  5979   select_eq_Ex     -> some_eq_ex
  5980   selectI2EX       -> someI2_ex
  5981   selectI2         -> someI2
  5982   selectI          -> someI
  5983   select1_equality -> some1_equality
  5984   Eps_sym_eq       -> some_sym_eq_trivial
  5985   Eps_eq           -> some_eq_trivial
  5986 
  5987 * HOL: exhaust_tac on datatypes superceded by new generic case_tac;
  5988 
  5989 * HOL: removed obsolete theorem binding expand_if (refer to split_if
  5990 instead);
  5991 
  5992 * HOL: the recursion equations generated by 'recdef' are now called
  5993 f.simps instead of f.rules;
  5994 
  5995 * HOL: qed_spec_mp now also handles bounded ALL as well;
  5996 
  5997 * HOL: 0 is now overloaded, so the type constraint ":: nat" may
  5998 sometimes be needed;
  5999 
  6000 * HOL: the constant for "f``x" is now "image" rather than "op ``";
  6001 
  6002 * HOL: the constant for "f-``x" is now "vimage" rather than "op -``";
  6003 
  6004 * HOL: the disjoint sum is now "<+>" instead of "Plus"; the cartesian
  6005 product is now "<*>" instead of "Times"; the lexicographic product is
  6006 now "<*lex*>" instead of "**";
  6007 
  6008 * HOL: theory Sexp is now in HOL/Induct examples (it used to be part
  6009 of main HOL, but was unused); better use HOL's datatype package;
  6010 
  6011 * HOL: removed "symbols" syntax for constant "override" of theory Map;
  6012 the old syntax may be recovered as follows:
  6013 
  6014   syntax (symbols)
  6015     override  :: "('a ~=> 'b) => ('a ~=> 'b) => ('a ~=> 'b)"
  6016       (infixl "\\<oplus>" 100)
  6017 
  6018 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  6019 
  6020 * HOL/ML: even fewer consts are declared as global (see theories Ord,
  6021 Lfp, Gfp, WF); this only affects ML packages that refer to const names
  6022 internally;
  6023 
  6024 * HOL and ZF: syntax for quotienting wrt an equivalence relation
  6025 changed from A/r to A//r;
  6026 
  6027 * ZF: new treatment of arithmetic (nat & int) may break some old
  6028 proofs;
  6029 
  6030 * Isar: renamed some attributes (RS -> THEN, simplify -> simplified,
  6031 rulify -> rule_format, elimify -> elim_format, ...);
  6032 
  6033 * Isar/Provers: intro/elim/dest attributes changed; renamed
  6034 intro/intro!/intro!! flags to intro!/intro/intro? (in most cases, one
  6035 should have to change intro!! to intro? only); replaced "delrule" by
  6036 "rule del";
  6037 
  6038 * Isar/HOL: renamed "intrs" to "intros" in inductive definitions;
  6039 
  6040 * Provers: strengthened force_tac by using new first_best_tac;
  6041 
  6042 * LaTeX document preparation: several changes of isabelle.sty (see
  6043 lib/texinputs);
  6044 
  6045 
  6046 *** Document preparation ***
  6047 
  6048 * formal comments (text blocks etc.) in new-style theories may now
  6049 contain antiquotations of thm/prop/term/typ/text to be presented
  6050 according to latex print mode; concrete syntax is like this:
  6051 @{term[show_types] "f(x) = a + x"};
  6052 
  6053 * isatool mkdir provides easy setup of Isabelle session directories,
  6054 including proper document sources;
  6055 
  6056 * generated LaTeX sources are now deleted after successful run
  6057 (isatool document -c); may retain a copy somewhere else via -D option
  6058 of isatool usedir;
  6059 
  6060 * isatool usedir -D now lets isatool latex -o sty update the Isabelle
  6061 style files, achieving self-contained LaTeX sources and simplifying
  6062 LaTeX debugging;
  6063 
  6064 * old-style theories now produce (crude) LaTeX output as well;
  6065 
  6066 * browser info session directories are now self-contained (may be put
  6067 on WWW server seperately); improved graphs of nested sessions; removed
  6068 graph for 'all sessions';
  6069 
  6070 * several improvements in isabelle style files; \isabellestyle{it}
  6071 produces fake math mode output; \isamarkupheader is now \section by
  6072 default; see lib/texinputs/isabelle.sty etc.;
  6073 
  6074 
  6075 *** Isar ***
  6076 
  6077 * Isar/Pure: local results and corresponding term bindings are now
  6078 subject to Hindley-Milner polymorphism (similar to ML); this
  6079 accommodates incremental type-inference very nicely;
  6080 
  6081 * Isar/Pure: new derived language element 'obtain' supports
  6082 generalized existence reasoning;
  6083 
  6084 * Isar/Pure: new calculational elements 'moreover' and 'ultimately'
  6085 support accumulation of results, without applying any rules yet;
  6086 useful to collect intermediate results without explicit name
  6087 references, and for use with transitivity rules with more than 2
  6088 premises;
  6089 
  6090 * Isar/Pure: scalable support for case-analysis type proofs: new
  6091 'case' language element refers to local contexts symbolically, as
  6092 produced by certain proof methods; internally, case names are attached
  6093 to theorems as "tags";
  6094 
  6095 * Isar/Pure: theory command 'hide' removes declarations from
  6096 class/type/const name spaces;
  6097 
  6098 * Isar/Pure: theory command 'defs' supports option "(overloaded)" to
  6099 indicate potential overloading;
  6100 
  6101 * Isar/Pure: changed syntax of local blocks from {{ }} to { };
  6102 
  6103 * Isar/Pure: syntax of sorts made 'inner', i.e. have to write
  6104 "{a,b,c}" instead of {a,b,c};
  6105 
  6106 * Isar/Pure now provides its own version of intro/elim/dest
  6107 attributes; useful for building new logics, but beware of confusion
  6108 with the version in Provers/classical;
  6109 
  6110 * Isar/Pure: the local context of (non-atomic) goals is provided via
  6111 case name 'antecedent';
  6112 
  6113 * Isar/Pure: removed obsolete 'transfer' attribute (transfer of thms
  6114 to the current context is now done automatically);
  6115 
  6116 * Isar/Pure: theory command 'method_setup' provides a simple interface
  6117 for definining proof methods in ML;
  6118 
  6119 * Isar/Provers: intro/elim/dest attributes changed; renamed
  6120 intro/intro!/intro!! flags to intro!/intro/intro? (INCOMPATIBILITY, in
  6121 most cases, one should have to change intro!! to intro? only);
  6122 replaced "delrule" by "rule del";
  6123 
  6124 * Isar/Provers: new 'hypsubst' method, plain 'subst' method and
  6125 'symmetric' attribute (the latter supercedes [RS sym]);
  6126 
  6127 * Isar/Provers: splitter support (via 'split' attribute and 'simp'
  6128 method modifier); 'simp' method: 'only:' modifier removes loopers as
  6129 well (including splits);
  6130 
  6131 * Isar/Provers: Simplifier and Classical methods now support all kind
  6132 of modifiers used in the past, including 'cong', 'iff', etc.
  6133 
  6134 * Isar/Provers: added 'fastsimp' and 'clarsimp' methods (combination
  6135 of Simplifier and Classical reasoner);
  6136 
  6137 * Isar/HOL: new proof method 'cases' and improved version of 'induct'
  6138 now support named cases; major packages (inductive, datatype, primrec,
  6139 recdef) support case names and properly name parameters;
  6140 
  6141 * Isar/HOL: new transitivity rules for substitution in inequalities --
  6142 monotonicity conditions are extracted to be proven at end of
  6143 calculations;
  6144 
  6145 * Isar/HOL: removed 'case_split' thm binding, should use 'cases' proof
  6146 method anyway;
  6147 
  6148 * Isar/HOL: removed old expand_if = split_if; theorems if_splits =
  6149 split_if split_if_asm; datatype package provides theorems foo.splits =
  6150 foo.split foo.split_asm for each datatype;
  6151 
  6152 * Isar/HOL: tuned inductive package, rename "intrs" to "intros"
  6153 (potential INCOMPATIBILITY), emulation of mk_cases feature for proof
  6154 scripts: new 'inductive_cases' command and 'ind_cases' method; (Note:
  6155 use "(cases (simplified))" method in proper proof texts);
  6156 
  6157 * Isar/HOL: added global 'arith_split' attribute for 'arith' method;
  6158 
  6159 * Isar: names of theorems etc. may be natural numbers as well;
  6160 
  6161 * Isar: 'pr' command: optional arguments for goals_limit and
  6162 ProofContext.prems_limit; no longer prints theory contexts, but only
  6163 proof states;
  6164 
  6165 * Isar: diagnostic commands 'pr', 'thm', 'prop', 'term', 'typ' admit
  6166 additional print modes to be specified; e.g. "pr(latex)" will print
  6167 proof state according to the Isabelle LaTeX style;
  6168 
  6169 * Isar: improved support for emulating tactic scripts, including proof
  6170 methods 'rule_tac' etc., 'cut_tac', 'thin_tac', 'subgoal_tac',
  6171 'rename_tac', 'rotate_tac', 'tactic', and 'case_tac' / 'induct_tac'
  6172 (for HOL datatypes);
  6173 
  6174 * Isar: simplified (more robust) goal selection of proof methods: 1st
  6175 goal, all goals, or explicit goal specifier (tactic emulation); thus
  6176 'proof method scripts' have to be in depth-first order;
  6177 
  6178 * Isar: tuned 'let' syntax: replaced 'as' keyword by 'and';
  6179 
  6180 * Isar: removed 'help' command, which hasn't been too helpful anyway;
  6181 should instead use individual commands for printing items
  6182 (print_commands, print_methods etc.);
  6183 
  6184 * Isar: added 'nothing' --- the empty list of theorems;
  6185 
  6186 
  6187 *** HOL ***
  6188 
  6189 * HOL/MicroJava: formalization of a fragment of Java, together with a
  6190 corresponding virtual machine and a specification of its bytecode
  6191 verifier and a lightweight bytecode verifier, including proofs of
  6192 type-safety; by Gerwin Klein, Tobias Nipkow, David von Oheimb, and
  6193 Cornelia Pusch (see also the homepage of project Bali at
  6194 http://isabelle.in.tum.de/Bali/);
  6195 
  6196 * HOL/Algebra: new theory of rings and univariate polynomials, by
  6197 Clemens Ballarin;
  6198 
  6199 * HOL/NumberTheory: fundamental Theorem of Arithmetic, Chinese
  6200 Remainder Theorem, Fermat/Euler Theorem, Wilson's Theorem, by Thomas M
  6201 Rasmussen;
  6202 
  6203 * HOL/Lattice: fundamental concepts of lattice theory and order
  6204 structures, including duals, properties of bounds versus algebraic
  6205 laws, lattice operations versus set-theoretic ones, the Knaster-Tarski
  6206 Theorem for complete lattices etc.; may also serve as a demonstration
  6207 for abstract algebraic reasoning using axiomatic type classes, and
  6208 mathematics-style proof in Isabelle/Isar; by Markus Wenzel;
  6209 
  6210 * HOL/Prolog: a (bare-bones) implementation of Lambda-Prolog, by David
  6211 von Oheimb;
  6212 
  6213 * HOL/IMPP: extension of IMP with local variables and mutually
  6214 recursive procedures, by David von Oheimb;
  6215 
  6216 * HOL/Lambda: converted into new-style theory and document;
  6217 
  6218 * HOL/ex/Multiquote: example of multiple nested quotations and
  6219 anti-quotations -- basically a generalized version of de-Bruijn
  6220 representation; very useful in avoiding lifting of operations;
  6221 
  6222 * HOL/record: added general record equality rule to simpset; fixed
  6223 select-update simplification procedure to handle extended records as
  6224 well; admit "r" as field name;
  6225 
  6226 * HOL: 0 is now overloaded over the new sort "zero", allowing its use with
  6227 other numeric types and also as the identity of groups, rings, etc.;
  6228 
  6229 * HOL: new axclass plus_ac0 for addition with the AC-laws and 0 as identity.
  6230 Types nat and int belong to this axclass;
  6231 
  6232 * HOL: greatly improved simplification involving numerals of type nat, int, real:
  6233    (i + #8 + j) = Suc k simplifies to  #7 + (i + j) = k
  6234    i*j + k + j*#3*i     simplifies to  #4*(i*j) + k
  6235   two terms #m*u and #n*u are replaced by #(m+n)*u
  6236     (where #m, #n and u can implicitly be 1; this is simproc combine_numerals