NEWS
author haftmann
Wed Sep 08 13:25:22 2010 +0200 (2010-09-08)
changeset 39215 7b2631c91a95
parent 39199 720112792ba0
child 39239 47273e5b1441
child 39250 548a3e5521ab
permissions -rw-r--r--
NEWS
     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 * Renamed lemmas: expand_fun_eq -> ext_iff, expand_set_eq -> set_ext_iff
    75 
    76 * Renamed class eq and constant eq (for code generation) to class equal
    77 and constant equal, plus renaming of related facts and various tuning.
    78 INCOMPATIBILITY.
    79 
    80 * Scala (2.8 or higher) has been added to the target languages of
    81 the code generator.
    82 
    83 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
    84 
    85 * Theory SetsAndFunctions has been split into Function_Algebras and Set_Algebras;
    86 canonical names for instance definitions for functions; various improvements.
    87 INCOMPATIBILITY.
    88 
    89 * Records: logical foundation type for records do not carry a '_type' suffix
    90 any longer.  INCOMPATIBILITY.
    91 
    92 * Code generation for records: more idiomatic representation of record types.
    93 Warning: records are not covered by ancient SML code generation any longer.
    94 INCOMPATIBILITY.  In cases of need, a suitable rep_datatype declaration
    95 helps to succeed then:
    96 
    97   record 'a foo = ...
    98   ...
    99   rep_datatype foo_ext ...
   100 
   101 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   102 INCOMPATIBILITY.
   103 
   104 * Quickcheck in locales considers interpretations of that locale for
   105 counter example search.
   106 
   107 * Theory Library/Monad_Syntax provides do-syntax for monad types.  Syntax
   108 in Library/State_Monad has been changed to avoid ambiguities.
   109 INCOMPATIBILITY.
   110 
   111 * Code generator: export_code without explicit file declaration prints
   112 to standard output.  INCOMPATIBILITY.
   113 
   114 * Abolished symbol type names:  "prod" and "sum" replace "*" and "+"
   115 respectively.  INCOMPATIBILITY.
   116 
   117 * Constant "split" has been merged with constant "prod_case";  names
   118 of ML functions, facts etc. involving split have been retained so far,
   119 though.  INCOMPATIBILITY.
   120 
   121 * Dropped old infix syntax "mem" for List.member;  use "in set"
   122 instead.  INCOMPATIBILITY.
   123 
   124 * Refactoring of code-generation specific operations in List.thy
   125 
   126   constants
   127     null ~> List.null
   128 
   129   facts
   130     mem_iff ~> member_def
   131     null_empty ~> null_def
   132 
   133 INCOMPATIBILITY.  Note that these were not suppossed to be used
   134 regularly unless for striking reasons;  their main purpose was code
   135 generation.
   136 
   137 * Some previously unqualified names have been qualified:
   138 
   139   types
   140     bool ~> HOL.bool
   141     nat ~> Nat.nat
   142 
   143   constants
   144     Trueprop ~> HOL.Trueprop
   145     True ~> HOL.True
   146     False ~> HOL.False
   147     op & ~> HOL.conj
   148     op | ~> HOL.disj
   149     op --> ~> HOL.implies
   150     op = ~> HOL.eq
   151     Not ~> HOL.Not
   152     The ~> HOL.The
   153     All ~> HOL.All
   154     Ex ~> HOL.Ex
   155     Ex1 ~> HOL.Ex1
   156     Let ~> HOL.Let
   157     If ~> HOL.If
   158     Ball ~> Set.Ball
   159     Bex ~> Set.Bex
   160     Suc ~> Nat.Suc
   161     Pair ~> Product_Type.Pair
   162     fst ~> Product_Type.fst
   163     snd ~> Product_Type.snd
   164     curry ~> Product_Type.curry
   165     op : ~> Set.member
   166     Collect ~> Set.Collect
   167 
   168 INCOMPATIBILITY.
   169 
   170 * Removed simplifier congruence rule of "prod_case", as has for long
   171 been the case with "split".  INCOMPATIBILITY.
   172 
   173 * Datatype package: theorems generated for executable equality
   174 (class eq) carry proper names and are treated as default code
   175 equations.
   176 
   177 * Removed lemma Option.is_none_none (Duplicate of is_none_def).
   178 INCOMPATIBILITY.
   179 
   180 * List.thy: use various operations from the Haskell prelude when
   181 generating Haskell code.
   182 
   183 * code_simp.ML and method code_simp: simplification with rules determined
   184 by code generator.
   185 
   186 * code generator: do not print function definitions for case
   187 combinators any longer.
   188 
   189 * Multivariate Analysis: Introduced a type class for euclidean space. Most
   190 theorems are now stated in terms of euclidean spaces instead of finite
   191 cartesian products.
   192 
   193   types
   194     real ^ 'n ~>  'a::real_vector
   195               ~>  'a::euclidean_space
   196               ~>  'a::ordered_euclidean_space
   197         (depends on your needs)
   198 
   199   constants
   200      _ $ _        ~> _ $$ _
   201      \<chi> x. _  ~> \<chi>\<chi> x. _
   202      CARD('n)     ~> DIM('a)
   203 
   204 Also note that the indices are now natural numbers and not from some finite
   205 type. Finite cartesian products of euclidean spaces, products of euclidean
   206 spaces the real and complex numbers are instantiated to be euclidean_spaces.
   207 
   208 INCOMPATIBILITY.
   209 
   210 * Probability: Introduced pinfreal as real numbers with infinity. Use pinfreal
   211 as value for measures. Introduces Lebesgue Measure based on the integral in
   212 Multivariate Analysis. Proved Radon Nikodym for arbitrary sigma finite measure
   213 spaces.
   214 
   215  INCOMPATIBILITY.
   216 
   217 * Inductive package: offers new command "inductive_simps" to automatically
   218 derive instantiated and simplified equations for inductive predicates,
   219 similar to inductive_cases.
   220 
   221 * "bij f" is now an abbreviation of "bij_betw f UNIV UNIV". surj_on is a
   222 generalization of surj, and "surj f" is now a abbreviation of "surj_on f UNIV".
   223 The theorems bij_def and surj_def are unchanged.
   224 
   225 *** FOL ***
   226 
   227 * All constant names are now qualified.  INCOMPATIBILITY.
   228 
   229 
   230 *** ZF ***
   231 
   232 * All constant names are now qualified.  INCOMPATIBILITY.
   233 
   234 
   235 *** ML ***
   236 
   237 * Configuration option show_question_marks only affects regular pretty
   238 printing of types and terms, not raw Term.string_of_vname.
   239 
   240 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
   241 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
   242 @{thms} for most purposes.
   243 
   244 * ML structure Unsynchronized never opened, not even in Isar
   245 interaction mode as before.  Old Unsynchronized.set etc. have been
   246 discontinued -- use plain := instead.  This should be *rare* anyway,
   247 since modern tools always work via official context data, notably
   248 configuration options.
   249 
   250 * ML antiquotations @{theory} and @{theory_ref} refer to named
   251 theories from the ancestry of the current context, not any accidental
   252 theory loader state as before.  Potential INCOMPATIBILITY, subtle
   253 change in semantics.
   254 
   255 
   256 *** System ***
   257 
   258 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   259 
   260 
   261 
   262 New in Isabelle2009-2 (June 2010)
   263 ---------------------------------
   264 
   265 *** General ***
   266 
   267 * Authentic syntax for *all* logical entities (type classes, type
   268 constructors, term constants): provides simple and robust
   269 correspondence between formal entities and concrete syntax.  Within
   270 the parse tree / AST representations, "constants" are decorated by
   271 their category (class, type, const) and spelled out explicitly with
   272 their full internal name.
   273 
   274 Substantial INCOMPATIBILITY concerning low-level syntax declarations
   275 and translations (translation rules and translation functions in ML).
   276 Some hints on upgrading:
   277 
   278   - Many existing uses of 'syntax' and 'translations' can be replaced
   279     by more modern 'type_notation', 'notation' and 'abbreviation',
   280     which are independent of this issue.
   281 
   282   - 'translations' require markup within the AST; the term syntax
   283     provides the following special forms:
   284 
   285       CONST c   -- produces syntax version of constant c from context
   286       XCONST c  -- literally c, checked as constant from context
   287       c         -- literally c, if declared by 'syntax'
   288 
   289     Plain identifiers are treated as AST variables -- occasionally the
   290     system indicates accidental variables via the error "rhs contains
   291     extra variables".
   292 
   293     Type classes and type constructors are marked according to their
   294     concrete syntax.  Some old translations rules need to be written
   295     for the "type" category, using type constructor application
   296     instead of pseudo-term application of the default category
   297     "logic".
   298 
   299   - 'parse_translation' etc. in ML may use the following
   300     antiquotations:
   301 
   302       @{class_syntax c}   -- type class c within parse tree / AST
   303       @{term_syntax c}    -- type constructor c within parse tree / AST
   304       @{const_syntax c}   -- ML version of "CONST c" above
   305       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
   306 
   307   - Literal types within 'typed_print_translations', i.e. those *not*
   308     represented as pseudo-terms are represented verbatim.  Use @{class
   309     c} or @{type_name c} here instead of the above syntax
   310     antiquotations.
   311 
   312 Note that old non-authentic syntax was based on unqualified base
   313 names, so all of the above "constant" names would coincide.  Recall
   314 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
   315 diagnose syntax problems.
   316 
   317 * Type constructors admit general mixfix syntax, not just infix.
   318 
   319 * Concrete syntax may be attached to local entities without a proof
   320 body, too.  This works via regular mixfix annotations for 'fix',
   321 'def', 'obtain' etc. or via the explicit 'write' command, which is
   322 similar to the 'notation' command in theory specifications.
   323 
   324 * Discontinued unnamed infix syntax (legacy feature for many years) --
   325 need to specify constant name and syntax separately.  Internal ML
   326 datatype constructors have been renamed from InfixName to Infix etc.
   327 Minor INCOMPATIBILITY.
   328 
   329 * Schematic theorem statements need to be explicitly markup as such,
   330 via commands 'schematic_lemma', 'schematic_theorem',
   331 'schematic_corollary'.  Thus the relevance of the proof is made
   332 syntactically clear, which impacts performance in a parallel or
   333 asynchronous interactive environment.  Minor INCOMPATIBILITY.
   334 
   335 * Use of cumulative prems via "!" in some proof methods has been
   336 discontinued (old legacy feature).
   337 
   338 * References 'trace_simp' and 'debug_simp' have been replaced by
   339 configuration options stored in the context. Enabling tracing (the
   340 case of debugging is similar) in proofs works via
   341 
   342   using [[trace_simp = true]]
   343 
   344 Tracing is then active for all invocations of the simplifier in
   345 subsequent goal refinement steps. Tracing may also still be enabled or
   346 disabled via the ProofGeneral settings menu.
   347 
   348 * Separate commands 'hide_class', 'hide_type', 'hide_const',
   349 'hide_fact' replace the former 'hide' KIND command.  Minor
   350 INCOMPATIBILITY.
   351 
   352 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
   353 more efficient than combinations with -q1 or -q2.
   354 
   355 
   356 *** Pure ***
   357 
   358 * Proofterms record type-class reasoning explicitly, using the
   359 "unconstrain" operation internally.  This eliminates all sort
   360 constraints from a theorem and proof, introducing explicit
   361 OFCLASS-premises.  On the proof term level, this operation is
   362 automatically applied at theorem boundaries, such that closed proofs
   363 are always free of sort constraints.  INCOMPATIBILITY for tools that
   364 inspect proof terms.
   365 
   366 * Local theory specifications may depend on extra type variables that
   367 are not present in the result type -- arguments TYPE('a) :: 'a itself
   368 are added internally.  For example:
   369 
   370   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
   371 
   372 * Predicates of locales introduced by classes carry a mandatory
   373 "class" prefix.  INCOMPATIBILITY.
   374 
   375 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
   376 
   377 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
   378 'class' instead.
   379 
   380 * Command 'code_reflect' allows to incorporate generated ML code into
   381 runtime environment; replaces immature code_datatype antiquotation.
   382 INCOMPATIBILITY.
   383 
   384 * Code generator: simple concept for abstract datatypes obeying
   385 invariants.
   386 
   387 * Code generator: details of internal data cache have no impact on the
   388 user space functionality any longer.
   389 
   390 * Methods "unfold_locales" and "intro_locales" ignore non-locale
   391 subgoals.  This is more appropriate for interpretations with 'where'.
   392 INCOMPATIBILITY.
   393 
   394 * Command 'example_proof' opens an empty proof body.  This allows to
   395 experiment with Isar, without producing any persistent result.
   396 
   397 * Commands 'type_notation' and 'no_type_notation' declare type syntax
   398 within a local theory context, with explicit checking of the
   399 constructors involved (in contrast to the raw 'syntax' versions).
   400 
   401 * Commands 'types' and 'typedecl' now work within a local theory
   402 context -- without introducing dependencies on parameters or
   403 assumptions, which is not possible in Isabelle/Pure.
   404 
   405 * Command 'defaultsort' has been renamed to 'default_sort', it works
   406 within a local theory context.  Minor INCOMPATIBILITY.
   407 
   408 
   409 *** HOL ***
   410 
   411 * Command 'typedef' now works within a local theory context -- without
   412 introducing dependencies on parameters or assumptions, which is not
   413 possible in Isabelle/Pure/HOL.  Note that the logical environment may
   414 contain multiple interpretations of local typedefs (with different
   415 non-emptiness proofs), even in a global theory context.
   416 
   417 * New package for quotient types.  Commands 'quotient_type' and
   418 'quotient_definition' may be used for defining types and constants by
   419 quotient constructions.  An example is the type of integers created by
   420 quotienting pairs of natural numbers:
   421 
   422   fun
   423     intrel :: "(nat * nat) => (nat * nat) => bool"
   424   where
   425     "intrel (x, y) (u, v) = (x + v = u + y)"
   426 
   427   quotient_type int = "nat * nat" / intrel
   428     by (auto simp add: equivp_def expand_fun_eq)
   429 
   430   quotient_definition
   431     "0::int" is "(0::nat, 0::nat)"
   432 
   433 The method "lifting" can be used to lift of theorems from the
   434 underlying "raw" type to the quotient type.  The example
   435 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
   436 construction and provides a reasoning infrastructure for finite sets.
   437 
   438 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
   439 clash with new theory Quotient in Main HOL.
   440 
   441 * Moved the SMT binding into the main HOL session, eliminating
   442 separate HOL-SMT session.
   443 
   444 * List membership infix mem operation is only an input abbreviation.
   445 INCOMPATIBILITY.
   446 
   447 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
   448 for future developements; former Library/Word.thy is still present in
   449 the AFP entry RSAPPS.
   450 
   451 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
   452 longer shadowed.  INCOMPATIBILITY.
   453 
   454 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
   455 INCOMPATIBILITY.
   456 
   457 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
   458 INCOMPATIBILITY.
   459 
   460 * Dropped normalizing_semiring etc; use the facts in semiring classes
   461 instead.  INCOMPATIBILITY.
   462 
   463 * Dropped several real-specific versions of lemmas about floor and
   464 ceiling; use the generic lemmas from theory "Archimedean_Field"
   465 instead.  INCOMPATIBILITY.
   466 
   467   floor_number_of_eq         ~> floor_number_of
   468   le_floor_eq_number_of      ~> number_of_le_floor
   469   le_floor_eq_zero           ~> zero_le_floor
   470   le_floor_eq_one            ~> one_le_floor
   471   floor_less_eq_number_of    ~> floor_less_number_of
   472   floor_less_eq_zero         ~> floor_less_zero
   473   floor_less_eq_one          ~> floor_less_one
   474   less_floor_eq_number_of    ~> number_of_less_floor
   475   less_floor_eq_zero         ~> zero_less_floor
   476   less_floor_eq_one          ~> one_less_floor
   477   floor_le_eq_number_of      ~> floor_le_number_of
   478   floor_le_eq_zero           ~> floor_le_zero
   479   floor_le_eq_one            ~> floor_le_one
   480   floor_subtract_number_of   ~> floor_diff_number_of
   481   floor_subtract_one         ~> floor_diff_one
   482   ceiling_number_of_eq       ~> ceiling_number_of
   483   ceiling_le_eq_number_of    ~> ceiling_le_number_of
   484   ceiling_le_zero_eq         ~> ceiling_le_zero
   485   ceiling_le_eq_one          ~> ceiling_le_one
   486   less_ceiling_eq_number_of  ~> number_of_less_ceiling
   487   less_ceiling_eq_zero       ~> zero_less_ceiling
   488   less_ceiling_eq_one        ~> one_less_ceiling
   489   ceiling_less_eq_number_of  ~> ceiling_less_number_of
   490   ceiling_less_eq_zero       ~> ceiling_less_zero
   491   ceiling_less_eq_one        ~> ceiling_less_one
   492   le_ceiling_eq_number_of    ~> number_of_le_ceiling
   493   le_ceiling_eq_zero         ~> zero_le_ceiling
   494   le_ceiling_eq_one          ~> one_le_ceiling
   495   ceiling_subtract_number_of ~> ceiling_diff_number_of
   496   ceiling_subtract_one       ~> ceiling_diff_one
   497 
   498 * Theory "Finite_Set": various folding_XXX locales facilitate the
   499 application of the various fold combinators on finite sets.
   500 
   501 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
   502 provides abstract red-black tree type which is backed by "RBT_Impl" as
   503 implementation.  INCOMPATIBILTY.
   504 
   505 * Theory Library/Coinductive_List has been removed -- superseded by
   506 AFP/thys/Coinductive.
   507 
   508 * Theory PReal, including the type "preal" and related operations, has
   509 been removed.  INCOMPATIBILITY.
   510 
   511 * Real: new development using Cauchy Sequences.
   512 
   513 * Split off theory "Big_Operators" containing setsum, setprod,
   514 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
   515 
   516 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
   517 "Int" etc.  INCOMPATIBILITY.
   518 
   519 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
   520 
   521 * New set of rules "ac_simps" provides combined assoc / commute
   522 rewrites for all interpretations of the appropriate generic locales.
   523 
   524 * Renamed theory "OrderedGroup" to "Groups" and split theory
   525 "Ring_and_Field" into theories "Rings" and "Fields"; for more
   526 appropriate and more consistent names suitable for name prefixes
   527 within the HOL theories.  INCOMPATIBILITY.
   528 
   529 * Some generic constants have been put to appropriate theories:
   530   - less_eq, less: Orderings
   531   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
   532   - inverse, divide: Rings
   533 INCOMPATIBILITY.
   534 
   535 * More consistent naming of type classes involving orderings (and
   536 lattices):
   537 
   538     lower_semilattice                   ~> semilattice_inf
   539     upper_semilattice                   ~> semilattice_sup
   540 
   541     dense_linear_order                  ~> dense_linorder
   542 
   543     pordered_ab_group_add               ~> ordered_ab_group_add
   544     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
   545     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
   546     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
   547     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
   548     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
   549     pordered_cancel_semiring            ~> ordered_cancel_semiring
   550     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
   551     pordered_comm_ring                  ~> ordered_comm_ring
   552     pordered_comm_semiring              ~> ordered_comm_semiring
   553     pordered_ring                       ~> ordered_ring
   554     pordered_ring_abs                   ~> ordered_ring_abs
   555     pordered_semiring                   ~> ordered_semiring
   556 
   557     ordered_ab_group_add                ~> linordered_ab_group_add
   558     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
   559     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
   560     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
   561     ordered_field                       ~> linordered_field
   562     ordered_field_no_lb                 ~> linordered_field_no_lb
   563     ordered_field_no_ub                 ~> linordered_field_no_ub
   564     ordered_field_dense_linear_order    ~> dense_linordered_field
   565     ordered_idom                        ~> linordered_idom
   566     ordered_ring                        ~> linordered_ring
   567     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
   568     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
   569     ordered_ring_strict                 ~> linordered_ring_strict
   570     ordered_semidom                     ~> linordered_semidom
   571     ordered_semiring                    ~> linordered_semiring
   572     ordered_semiring_1                  ~> linordered_semiring_1
   573     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
   574     ordered_semiring_strict             ~> linordered_semiring_strict
   575 
   576   The following slightly odd type classes have been moved to a
   577   separate theory Library/Lattice_Algebras:
   578 
   579     lordered_ab_group_add               ~> lattice_ab_group_add
   580     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
   581     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
   582     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
   583     lordered_ring                       ~> lattice_ring
   584 
   585 INCOMPATIBILITY.
   586 
   587 * Refined field classes:
   588   - classes division_ring_inverse_zero, field_inverse_zero,
   589     linordered_field_inverse_zero include rule inverse 0 = 0 --
   590     subsumes former division_by_zero class;
   591   - numerous lemmas have been ported from field to division_ring.
   592 INCOMPATIBILITY.
   593 
   594 * Refined algebra theorem collections:
   595   - dropped theorem group group_simps, use algebra_simps instead;
   596   - dropped theorem group ring_simps, use field_simps instead;
   597   - proper theorem collection field_simps subsumes former theorem
   598     groups field_eq_simps and field_simps;
   599   - dropped lemma eq_minus_self_iff which is a duplicate for
   600     equal_neg_zero.
   601 INCOMPATIBILITY.
   602 
   603 * Theory Finite_Set and List: some lemmas have been generalized from
   604 sets to lattices:
   605 
   606   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
   607   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
   608   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
   609   union_Union_fold_union        ~> sup_Sup_fold_sup
   610   Inter_fold_inter              ~> Inf_fold_inf
   611   Union_fold_union              ~> Sup_fold_sup
   612   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
   613   union_UNION_fold_union        ~> sup_SUPR_fold_sup
   614   INTER_fold_inter              ~> INFI_fold_inf
   615   UNION_fold_union              ~> SUPR_fold_sup
   616 
   617 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
   618 replaced by the more convenient lemmas Inf_empty and Sup_empty.
   619 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
   620 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
   621 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
   622 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
   623 
   624 * Reorganized theory Multiset: swapped notation of pointwise and
   625 multiset order:
   626 
   627   - pointwise ordering is instance of class order with standard syntax
   628     <= and <;
   629   - multiset ordering has syntax <=# and <#; partial order properties
   630     are provided by means of interpretation with prefix
   631     multiset_order;
   632   - less duplication, less historical organization of sections,
   633     conversion from associations lists to multisets, rudimentary code
   634     generation;
   635   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
   636     if needed.
   637 
   638 Renamed:
   639 
   640   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
   641   multi_count_ext  ~>  multiset_ext
   642   diff_union_inverse2  ~>  diff_union_cancelR
   643 
   644 INCOMPATIBILITY.
   645 
   646 * Theory Permutation: replaced local "remove" by List.remove1.
   647 
   648 * Code generation: ML and OCaml code is decorated with signatures.
   649 
   650 * Theory List: added transpose.
   651 
   652 * Library/Nat_Bijection.thy is a collection of bijective functions
   653 between nat and other types, which supersedes the older libraries
   654 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
   655 
   656   Constants:
   657   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
   658   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
   659   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
   660   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
   661   Countable.pair_encode           ~> prod_encode
   662   NatIso.prod2nat                 ~> prod_encode
   663   NatIso.nat2prod                 ~> prod_decode
   664   NatIso.sum2nat                  ~> sum_encode
   665   NatIso.nat2sum                  ~> sum_decode
   666   NatIso.list2nat                 ~> list_encode
   667   NatIso.nat2list                 ~> list_decode
   668   NatIso.set2nat                  ~> set_encode
   669   NatIso.nat2set                  ~> set_decode
   670 
   671   Lemmas:
   672   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
   673   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
   674   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
   675   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
   676   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
   677   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
   678   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
   679   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
   680   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
   681   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
   682   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
   683   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
   684   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
   685 
   686 * Sledgehammer:
   687   - Renamed ATP commands:
   688     atp_info     ~> sledgehammer running_atps
   689     atp_kill     ~> sledgehammer kill_atps
   690     atp_messages ~> sledgehammer messages
   691     atp_minimize ~> sledgehammer minimize
   692     print_atps   ~> sledgehammer available_atps
   693     INCOMPATIBILITY.
   694   - Added user's manual ("isabelle doc sledgehammer").
   695   - Added option syntax and "sledgehammer_params" to customize
   696     Sledgehammer's behavior.  See the manual for details.
   697   - Modified the Isar proof reconstruction code so that it produces
   698     direct proofs rather than proofs by contradiction.  (This feature
   699     is still experimental.)
   700   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
   701     full-typed mode.
   702   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
   703 
   704 * Nitpick:
   705   - Added and implemented "binary_ints" and "bits" options.
   706   - Added "std" option and implemented support for nonstandard models.
   707   - Added and implemented "finitize" option to improve the precision
   708     of infinite datatypes based on a monotonicity analysis.
   709   - Added support for quotient types.
   710   - Added support for "specification" and "ax_specification"
   711     constructs.
   712   - Added support for local definitions (for "function" and
   713     "termination" proofs).
   714   - Added support for term postprocessors.
   715   - Optimized "Multiset.multiset" and "FinFun.finfun".
   716   - Improved efficiency of "destroy_constrs" optimization.
   717   - Fixed soundness bugs related to "destroy_constrs" optimization and
   718     record getters.
   719   - Fixed soundness bug related to higher-order constructors.
   720   - Fixed soundness bug when "full_descrs" is enabled.
   721   - Improved precision of set constructs.
   722   - Added "atoms" option.
   723   - Added cache to speed up repeated Kodkod invocations on the same
   724     problems.
   725   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
   726     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
   727     "SAT4J_Light".  INCOMPATIBILITY.
   728   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
   729     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
   730   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
   731 
   732 * Method "induct" now takes instantiations of the form t, where t is not
   733   a variable, as a shorthand for "x == t", where x is a fresh variable.
   734   If this is not intended, t has to be enclosed in parentheses.
   735   By default, the equalities generated by definitional instantiations
   736   are pre-simplified, which may cause parameters of inductive cases
   737   to disappear, or may even delete some of the inductive cases.
   738   Use "induct (no_simp)" instead of "induct" to restore the old
   739   behaviour. The (no_simp) option is also understood by the "cases"
   740   and "nominal_induct" methods, which now perform pre-simplification, too.
   741   INCOMPATIBILITY.
   742 
   743 
   744 *** HOLCF ***
   745 
   746 * Variable names in lemmas generated by the domain package have
   747 changed; the naming scheme is now consistent with the HOL datatype
   748 package.  Some proof scripts may be affected, INCOMPATIBILITY.
   749 
   750 * The domain package no longer defines the function "foo_copy" for
   751 recursive domain "foo".  The reach lemma is now stated directly in
   752 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
   753 be reformulated in terms of "foo_take", INCOMPATIBILITY.
   754 
   755 * Most definedness lemmas generated by the domain package (previously
   756 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
   757 like "foo$x = UU <-> x = UU", which works better as a simp rule.
   758 Proofs that used definedness lemmas as intro rules may break,
   759 potential INCOMPATIBILITY.
   760 
   761 * Induction and casedist rules generated by the domain package now
   762 declare proper case_names (one called "bottom", and one named for each
   763 constructor).  INCOMPATIBILITY.
   764 
   765 * For mutually-recursive domains, separate "reach" and "take_lemma"
   766 rules are generated for each domain, INCOMPATIBILITY.
   767 
   768   foo_bar.reach       ~> foo.reach  bar.reach
   769   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
   770 
   771 * Some lemmas generated by the domain package have been renamed for
   772 consistency with the datatype package, INCOMPATIBILITY.
   773 
   774   foo.ind        ~> foo.induct
   775   foo.finite_ind ~> foo.finite_induct
   776   foo.coind      ~> foo.coinduct
   777   foo.casedist   ~> foo.exhaust
   778   foo.exhaust    ~> foo.nchotomy
   779 
   780 * For consistency with other definition packages, the fixrec package
   781 now generates qualified theorem names, INCOMPATIBILITY.
   782 
   783   foo_simps  ~> foo.simps
   784   foo_unfold ~> foo.unfold
   785   foo_induct ~> foo.induct
   786 
   787 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
   788 method and internal fixrec proofs now use the default simpset instead.
   789 INCOMPATIBILITY.
   790 
   791 * The "contlub" predicate has been removed.  Proof scripts should use
   792 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
   793 
   794 * The "admw" predicate has been removed, INCOMPATIBILITY.
   795 
   796 * The constants cpair, cfst, and csnd have been removed in favor of
   797 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
   798 
   799 
   800 *** ML ***
   801 
   802 * Antiquotations for basic formal entities:
   803 
   804     @{class NAME}         -- type class
   805     @{class_syntax NAME}  -- syntax representation of the above
   806 
   807     @{type_name NAME}     -- logical type
   808     @{type_abbrev NAME}   -- type abbreviation
   809     @{nonterminal NAME}   -- type of concrete syntactic category
   810     @{type_syntax NAME}   -- syntax representation of any of the above
   811 
   812     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
   813     @{const_abbrev NAME}  -- abbreviated constant
   814     @{const_syntax NAME}  -- syntax representation of any of the above
   815 
   816 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
   817 syntax constant (cf. 'syntax' command).
   818 
   819 * Antiquotation @{make_string} inlines a function to print arbitrary
   820 values similar to the ML toplevel.  The result is compiler dependent
   821 and may fall back on "?" in certain situations.
   822 
   823 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
   824 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
   825 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
   826 not work with the asynchronous Isar document model.
   827 
   828 * Configuration options now admit dynamic default values, depending on
   829 the context or even global references.
   830 
   831 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
   832 uses an efficient external library if available (for Poly/ML).
   833 
   834 * Renamed some important ML structures, while keeping the old names
   835 for some time as aliases within the structure Legacy:
   836 
   837   OuterKeyword  ~>  Keyword
   838   OuterLex      ~>  Token
   839   OuterParse    ~>  Parse
   840   OuterSyntax   ~>  Outer_Syntax
   841   PrintMode     ~>  Print_Mode
   842   SpecParse     ~>  Parse_Spec
   843   ThyInfo       ~>  Thy_Info
   844   ThyLoad       ~>  Thy_Load
   845   ThyOutput     ~>  Thy_Output
   846   TypeInfer     ~>  Type_Infer
   847 
   848 Note that "open Legacy" simplifies porting of sources, but forgetting
   849 to remove it again will complicate porting again in the future.
   850 
   851 * Most operations that refer to a global context are named
   852 accordingly, e.g. Simplifier.global_context or
   853 ProofContext.init_global.  There are some situations where a global
   854 context actually works, but under normal circumstances one needs to
   855 pass the proper local context through the code!
   856 
   857 * Discontinued old TheoryDataFun with its copy/init operation -- data
   858 needs to be pure.  Functor Theory_Data_PP retains the traditional
   859 Pretty.pp argument to merge, which is absent in the standard
   860 Theory_Data version.
   861 
   862 * Sorts.certify_sort and derived "cert" operations for types and terms
   863 no longer minimize sorts.  Thus certification at the boundary of the
   864 inference kernel becomes invariant under addition of class relations,
   865 which is an important monotonicity principle.  Sorts are now minimized
   866 in the syntax layer only, at the boundary between the end-user and the
   867 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
   868 explicitly in rare situations.
   869 
   870 * Renamed old-style Drule.standard to Drule.export_without_context, to
   871 emphasize that this is in no way a standard operation.
   872 INCOMPATIBILITY.
   873 
   874 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
   875 usual for resolution.  Rare INCOMPATIBILITY.
   876 
   877 * Renamed varify/unvarify operations to varify_global/unvarify_global
   878 to emphasize that these only work in a global situation (which is
   879 quite rare).
   880 
   881 * Curried take and drop in library.ML; negative length is interpreted
   882 as infinity (as in chop).  Subtle INCOMPATIBILITY.
   883 
   884 * Proof terms: type substitutions on proof constants now use canonical
   885 order of type variables.  INCOMPATIBILITY for tools working with proof
   886 terms.
   887 
   888 * Raw axioms/defs may no longer carry sort constraints, and raw defs
   889 may no longer carry premises.  User-level specifications are
   890 transformed accordingly by Thm.add_axiom/add_def.
   891 
   892 
   893 *** System ***
   894 
   895 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
   896 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
   897 proof terms are enabled unconditionally in the new HOL-Proofs image.
   898 
   899 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
   900 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
   901 respectively.
   902 
   903 * Old lib/scripts/polyml-platform is superseded by the
   904 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
   905 variant, even on a 64 bit machine.  The following example setting
   906 prefers 64 bit if available:
   907 
   908   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
   909 
   910 * The preliminary Isabelle/jEdit application demonstrates the emerging
   911 Isabelle/Scala layer for advanced prover interaction and integration.
   912 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
   913 component.
   914 
   915 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
   916 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
   917 similar to the default assignment of the document preparation system
   918 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
   919 provides some operations for direct access to the font without asking
   920 the user for manual installation.
   921 
   922 
   923 
   924 New in Isabelle2009-1 (December 2009)
   925 -------------------------------------
   926 
   927 *** General ***
   928 
   929 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
   930 one backslash should be used, even in ML sources.
   931 
   932 
   933 *** Pure ***
   934 
   935 * Locale interpretation propagates mixins along the locale hierarchy.
   936 The currently only available mixins are the equations used to map
   937 local definitions to terms of the target domain of an interpretation.
   938 
   939 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
   940 loc" to print all interpretations of locale "loc" in the theory.
   941 Interpretations in proofs are not shown.
   942 
   943 * Thoroughly revised locales tutorial.  New section on conditional
   944 interpretation.
   945 
   946 * On instantiation of classes, remaining undefined class parameters
   947 are formally declared.  INCOMPATIBILITY.
   948 
   949 
   950 *** Document preparation ***
   951 
   952 * New generalized style concept for printing terms: @{foo (style) ...}
   953 instead of @{foo_style style ...}  (old form is still retained for
   954 backward compatibility).  Styles can be also applied for
   955 antiquotations prop, term_type and typeof.
   956 
   957 
   958 *** HOL ***
   959 
   960 * New proof method "smt" for a combination of first-order logic with
   961 equality, linear and nonlinear (natural/integer/real) arithmetic, and
   962 fixed-size bitvectors; there is also basic support for higher-order
   963 features (esp. lambda abstractions).  It is an incomplete decision
   964 procedure based on external SMT solvers using the oracle mechanism;
   965 for the SMT solver Z3, this method is proof-producing.  Certificates
   966 are provided to avoid calling the external solvers solely for
   967 re-checking proofs.  Due to a remote SMT service there is no need for
   968 installing SMT solvers locally.  See src/HOL/SMT.
   969 
   970 * New commands to load and prove verification conditions generated by
   971 the Boogie program verifier or derived systems (e.g. the Verifying C
   972 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
   973 
   974 * New counterexample generator tool 'nitpick' based on the Kodkod
   975 relational model finder.  See src/HOL/Tools/Nitpick and
   976 src/HOL/Nitpick_Examples.
   977 
   978 * New commands 'code_pred' and 'values' to invoke the predicate
   979 compiler and to enumerate values of inductive predicates.
   980 
   981 * A tabled implementation of the reflexive transitive closure.
   982 
   983 * New implementation of quickcheck uses generic code generator;
   984 default generators are provided for all suitable HOL types, records
   985 and datatypes.  Old quickcheck can be re-activated importing theory
   986 Library/SML_Quickcheck.
   987 
   988 * New testing tool Mirabelle for automated proof tools.  Applies
   989 several tools and tactics like sledgehammer, metis, or quickcheck, to
   990 every proof step in a theory.  To be used in batch mode via the
   991 "mirabelle" utility.
   992 
   993 * New proof method "sos" (sum of squares) for nonlinear real
   994 arithmetic (originally due to John Harison). It requires theory
   995 Library/Sum_Of_Squares.  It is not a complete decision procedure but
   996 works well in practice on quantifier-free real arithmetic with +, -,
   997 *, ^, =, <= and <, i.e. boolean combinations of equalities and
   998 inequalities between polynomials.  It makes use of external
   999 semidefinite programming solvers.  Method "sos" generates a
  1000 certificate that can be pasted into the proof thus avoiding the need
  1001 to call an external tool every time the proof is checked.  See
  1002 src/HOL/Library/Sum_Of_Squares.
  1003 
  1004 * New method "linarith" invokes existing linear arithmetic decision
  1005 procedure only.
  1006 
  1007 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1008 
  1009 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1010 Causes full type information to be output to the ATPs.  This slows
  1011 ATPs down considerably but eliminates a source of unsound "proofs"
  1012 that fail later.
  1013 
  1014 * New method "metisFT": A version of metis that uses full type
  1015 information in order to avoid failures of proof reconstruction.
  1016 
  1017 * New evaluator "approximate" approximates an real valued term using
  1018 the same method as the approximation method.
  1019 
  1020 * Method "approximate" now supports arithmetic expressions as
  1021 boundaries of intervals and implements interval splitting and Taylor
  1022 series expansion.
  1023 
  1024 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1025 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1026 
  1027 * New theory SupInf of the supremum and infimum operators for sets of
  1028 reals.
  1029 
  1030 * New theory Probability, which contains a development of measure
  1031 theory, eventually leading to Lebesgue integration and probability.
  1032 
  1033 * Extended Multivariate Analysis to include derivation and Brouwer's
  1034 fixpoint theorem.
  1035 
  1036 * Reorganization of number theory, INCOMPATIBILITY:
  1037   - new number theory development for nat and int, in theories Divides
  1038     and GCD as well as in new session Number_Theory
  1039   - some constants and facts now suffixed with _nat and _int
  1040     accordingly
  1041   - former session NumberTheory now named Old_Number_Theory, including
  1042     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1043   - moved theory Pocklington from src/HOL/Library to
  1044     src/HOL/Old_Number_Theory
  1045 
  1046 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1047 lcm of finite and infinite sets. It is shown that they form a complete
  1048 lattice.
  1049 
  1050 * Class semiring_div requires superclass no_zero_divisors and proof of
  1051 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1052 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1053 generalized to class semiring_div, subsuming former theorems
  1054 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1055 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1056 INCOMPATIBILITY.
  1057 
  1058 * Refinements to lattice classes and sets:
  1059   - less default intro/elim rules in locale variant, more default
  1060     intro/elim rules in class variant: more uniformity
  1061   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1062     le_inf_iff
  1063   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1064     sup_aci)
  1065   - renamed ACI to inf_sup_aci
  1066   - new class "boolean_algebra"
  1067   - class "complete_lattice" moved to separate theory
  1068     "Complete_Lattice"; corresponding constants (and abbreviations)
  1069     renamed and with authentic syntax:
  1070     Set.Inf ~>    Complete_Lattice.Inf
  1071     Set.Sup ~>    Complete_Lattice.Sup
  1072     Set.INFI ~>   Complete_Lattice.INFI
  1073     Set.SUPR ~>   Complete_Lattice.SUPR
  1074     Set.Inter ~>  Complete_Lattice.Inter
  1075     Set.Union ~>  Complete_Lattice.Union
  1076     Set.INTER ~>  Complete_Lattice.INTER
  1077     Set.UNION ~>  Complete_Lattice.UNION
  1078   - authentic syntax for
  1079     Set.Pow
  1080     Set.image
  1081   - mere abbreviations:
  1082     Set.empty               (for bot)
  1083     Set.UNIV                (for top)
  1084     Set.inter               (for inf, formerly Set.Int)
  1085     Set.union               (for sup, formerly Set.Un)
  1086     Complete_Lattice.Inter  (for Inf)
  1087     Complete_Lattice.Union  (for Sup)
  1088     Complete_Lattice.INTER  (for INFI)
  1089     Complete_Lattice.UNION  (for SUPR)
  1090   - object-logic definitions as far as appropriate
  1091 
  1092 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1093 Un_subset_iff are explicitly deleted as default simp rules; then also
  1094 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1095 deleted to achieve the desired effect.
  1096 
  1097 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1098 rules by default any longer; the same applies to min_max.inf_absorb1
  1099 etc.  INCOMPATIBILITY.
  1100 
  1101 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1102 pred_set_conv by default.  INCOMPATIBILITY.
  1103 
  1104 * Power operations on relations and functions are now one dedicated
  1105 constant "compow" with infix syntax "^^".  Power operation on
  1106 multiplicative monoids retains syntax "^" and is now defined generic
  1107 in class power.  INCOMPATIBILITY.
  1108 
  1109 * Relation composition "R O S" now has a more standard argument order:
  1110 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1111 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1112 break, since the O_assoc rule was not rewritten like this.  Fix using
  1113 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1114 
  1115 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1116 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1117 INCOMPATIBILITY.
  1118 
  1119 * Most rules produced by inductive and datatype package have mandatory
  1120 prefixes.  INCOMPATIBILITY.
  1121 
  1122 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1123 the attribute of the same name.  Each of the theorems in the list
  1124 DERIV_intros assumes composition with an additional function and
  1125 matches a variable to the derivative, which has to be solved by the
  1126 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1127 of most elementary terms.  Former Maclauren.DERIV_tac and
  1128 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1129 INCOMPATIBILITY.
  1130 
  1131 * Code generator attributes follow the usual underscore convention:
  1132     code_unfold     replaces    code unfold
  1133     code_post       replaces    code post
  1134     etc.
  1135   INCOMPATIBILITY.
  1136 
  1137 * Renamed methods:
  1138     sizechange -> size_change
  1139     induct_scheme -> induction_schema
  1140   INCOMPATIBILITY.
  1141 
  1142 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1143 INCOMPATIBILITY, use "undefined" directly.
  1144 
  1145 * Renamed theorems:
  1146     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1147     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1148     Suc_plus1 -> Suc_eq_plus1
  1149     *anti_sym -> *antisym*
  1150     vector_less_eq_def -> vector_le_def
  1151   INCOMPATIBILITY.
  1152 
  1153 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1154 INCOMPATIBILITY.
  1155 
  1156 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1157 INCOMPATIBILITY.
  1158 
  1159 
  1160 *** HOLCF ***
  1161 
  1162 * Theory Representable defines a class "rep" of domains that are
  1163 representable (via an ep-pair) in the universal domain type "udom".
  1164 Instances are provided for all type constructors defined in HOLCF.
  1165 
  1166 * The 'new_domain' command is a purely definitional version of the
  1167 domain package, for representable domains.  Syntax is identical to the
  1168 old domain package.  The 'new_domain' package also supports indirect
  1169 recursion using previously-defined type constructors.  See
  1170 src/HOLCF/ex/New_Domain.thy for examples.
  1171 
  1172 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1173 on the left-hand side of an equation, and then performs
  1174 simplification.  Rewriting is done using rules declared with the
  1175 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1176 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1177 
  1178 * The pattern-match compiler in 'fixrec' can now handle constructors
  1179 with HOL function types.  Pattern-match combinators for the Pair
  1180 constructor are pre-configured.
  1181 
  1182 * The 'fixrec' package now produces better fixed-point induction rules
  1183 for mutually-recursive definitions:  Induction rules have conclusions
  1184 of the form "P foo bar" instead of "P <foo, bar>".
  1185 
  1186 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1187 been renamed to "below".  The name "below" now replaces "less" in many
  1188 theorem names.  (Legacy theorem names using "less" are still supported
  1189 as well.)
  1190 
  1191 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1192 patterns can be used to generate strictness rules, or to make
  1193 functions more strict (much like the bang-patterns supported by the
  1194 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1195 examples.
  1196 
  1197 
  1198 *** ML ***
  1199 
  1200 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1201 errors and run-time exceptions, including detailed source positions.
  1202 
  1203 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1204 identified entries, with some additional information such as source
  1205 position, logical grouping etc.
  1206 
  1207 * Theory and context data is now introduced by the simplified and
  1208 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1209 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1210 copy operation) is still available for some time.
  1211 
  1212 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1213 provides a high-level programming interface to synchronized state
  1214 variables with atomic update.  This works via pure function
  1215 application within a critical section -- its runtime should be as
  1216 short as possible; beware of deadlocks if critical code is nested,
  1217 either directly or indirectly via other synchronized variables!
  1218 
  1219 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1220 wraps raw ML references, explicitly indicating their non-thread-safe
  1221 behaviour.  The Isar toplevel keeps this structure open, to
  1222 accommodate Proof General as well as quick and dirty interactive
  1223 experiments with references.
  1224 
  1225 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1226 parallel tactical reasoning.
  1227 
  1228 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1229 are similar to SUBPROOF, but are slightly more flexible: only the
  1230 specified parts of the subgoal are imported into the context, and the
  1231 body tactic may introduce new subgoals and schematic variables.
  1232 
  1233 * Old tactical METAHYPS, which does not observe the proof context, has
  1234 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1235 or Subgoal.FOCUS etc.
  1236 
  1237 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1238 functors have their own ML name space there is no point to mark them
  1239 separately.)  Minor INCOMPATIBILITY.
  1240 
  1241 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1242 
  1243 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1244 INCOMPATIBILITY.
  1245 
  1246 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1247 mode, which avoids critical setmp.
  1248 
  1249 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1250 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1251 Attrib/Method.setup introduced in Isabelle2009.
  1252 
  1253 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1254 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1255 last resort.  INCOMPATIBILITY.
  1256 
  1257 * Display.pretty_thm now requires a proper context (cf. former
  1258 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1259 or even Display.pretty_thm_without_context as last resort.
  1260 INCOMPATIBILITY.
  1261 
  1262 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1263 Syntax.pretty_typ/term directly, preferably with proper context
  1264 instead of global theory.
  1265 
  1266 
  1267 *** System ***
  1268 
  1269 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1270 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1271 usedir option -q.
  1272 
  1273 * Support for additional "Isabelle components" via etc/components, see
  1274 also the system manual.
  1275 
  1276 * The isabelle makeall tool now operates on all components with
  1277 IsaMakefile, not just hardwired "logics".
  1278 
  1279 * Removed "compress" option from isabelle-process and isabelle usedir;
  1280 this is always enabled.
  1281 
  1282 * Discontinued support for Poly/ML 4.x versions.
  1283 
  1284 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  1285 on a given logic image.  This requires the lighttpd webserver and is
  1286 currently supported on Linux only.
  1287 
  1288 
  1289 
  1290 New in Isabelle2009 (April 2009)
  1291 --------------------------------
  1292 
  1293 *** General ***
  1294 
  1295 * Simplified main Isabelle executables, with less surprises on
  1296 case-insensitive file-systems (such as Mac OS).
  1297 
  1298   - The main Isabelle tool wrapper is now called "isabelle" instead of
  1299     "isatool."
  1300 
  1301   - The former "isabelle" alias for "isabelle-process" has been
  1302     removed (should rarely occur to regular users).
  1303 
  1304   - The former "isabelle-interface" and its alias "Isabelle" have been
  1305     removed (interfaces are now regular Isabelle tools).
  1306 
  1307 Within scripts and make files, the Isabelle environment variables
  1308 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  1309 respectively.  (The latter are still available as legacy feature.)
  1310 
  1311 The old isabelle-interface wrapper could react in confusing ways if
  1312 the interface was uninstalled or changed otherwise.  Individual
  1313 interface tool configuration is now more explicit, see also the
  1314 Isabelle system manual.  In particular, Proof General is now available
  1315 via "isabelle emacs".
  1316 
  1317 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  1318 purge installed copies of Isabelle executables and re-run "isabelle
  1319 install -p ...", or use symlinks.
  1320 
  1321 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  1322 old ~/isabelle, which was slightly non-standard and apt to cause
  1323 surprises on case-insensitive file-systems (such as Mac OS).
  1324 
  1325 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  1326 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  1327 care is required when using older releases of Isabelle.  Note that
  1328 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  1329 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  1330 
  1331 * Proofs of fully specified statements are run in parallel on
  1332 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  1333 a regular 4-core machine, if the initial heap space is made reasonably
  1334 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  1335 
  1336 * The main reference manuals ("isar-ref", "implementation", and
  1337 "system") have been updated and extended.  Formally checked references
  1338 as hyperlinks are now available uniformly.
  1339 
  1340 
  1341 *** Pure ***
  1342 
  1343 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  1344 respects.  The most important changes are listed below.  See the
  1345 Tutorial on Locales ("locales" manual) for details.
  1346 
  1347 - In locale expressions, instantiation replaces renaming.  Parameters
  1348 must be declared in a for clause.  To aid compatibility with previous
  1349 parameter inheritance, in locale declarations, parameters that are not
  1350 'touched' (instantiation position "_" or omitted) are implicitly added
  1351 with their syntax at the beginning of the for clause.
  1352 
  1353 - Syntax from abbreviations and definitions in locales is available in
  1354 locale expressions and context elements.  The latter is particularly
  1355 useful in locale declarations.
  1356 
  1357 - More flexible mechanisms to qualify names generated by locale
  1358 expressions.  Qualifiers (prefixes) may be specified in locale
  1359 expressions, and can be marked as mandatory (syntax: "name!:") or
  1360 optional (syntax "name?:").  The default depends for plain "name:"
  1361 depends on the situation where a locale expression is used: in
  1362 commands 'locale' and 'sublocale' prefixes are optional, in
  1363 'interpretation' and 'interpret' prefixes are mandatory.  The old
  1364 implicit qualifiers derived from the parameter names of a locale are
  1365 no longer generated.
  1366 
  1367 - Command "sublocale l < e" replaces "interpretation l < e".  The
  1368 instantiation clause in "interpretation" and "interpret" (square
  1369 brackets) is no longer available.  Use locale expressions.
  1370 
  1371 - When converting proof scripts, mandatory qualifiers in
  1372 'interpretation' and 'interpret' should be retained by default, even
  1373 if this is an INCOMPATIBILITY compared to former behavior.  In the
  1374 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  1375 in locale expressions range over a single locale instance only.
  1376 
  1377 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  1378 In existing theorem specifications replace the includes element by the
  1379 respective context elements of the included locale, omitting those
  1380 that are already present in the theorem specification.  Multiple
  1381 assume elements of a locale should be replaced by a single one
  1382 involving the locale predicate.  In the proof body, declarations (most
  1383 notably theorems) may be regained by interpreting the respective
  1384 locales in the proof context as required (command "interpret").
  1385 
  1386 If using "includes" in replacement of a target solely because the
  1387 parameter types in the theorem are not as general as in the target,
  1388 consider declaring a new locale with additional type constraints on
  1389 the parameters (context element "constrains").
  1390 
  1391 - Discontinued "locale (open)".  INCOMPATIBILITY.
  1392 
  1393 - Locale interpretation commands no longer attempt to simplify goal.
  1394 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  1395 methods intro_locales and unfold_locales to clarify.
  1396 
  1397 - Locale interpretation commands no longer accept interpretation
  1398 attributes.  INCOMPATIBILITY.
  1399 
  1400 * Class declaration: so-called "base sort" must not be given in import
  1401 list any longer, but is inferred from the specification.  Particularly
  1402 in HOL, write
  1403 
  1404     class foo = ...
  1405 
  1406 instead of
  1407 
  1408     class foo = type + ...
  1409 
  1410 * Class target: global versions of theorems stemming do not carry a
  1411 parameter prefix any longer.  INCOMPATIBILITY.
  1412 
  1413 * Class 'instance' command no longer accepts attached definitions.
  1414 INCOMPATIBILITY, use proper 'instantiation' target instead.
  1415 
  1416 * Recovered hiding of consts, which was accidentally broken in
  1417 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  1418 makes c inaccessible; consider using ``hide (open) const c'' instead.
  1419 
  1420 * Slightly more coherent Pure syntax, with updated documentation in
  1421 isar-ref manual.  Removed locales meta_term_syntax and
  1422 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  1423 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  1424 directly in regular applications.
  1425 
  1426 * There is a new syntactic category "float_const" for signed decimal
  1427 fractions (e.g. 123.45 or -123.45).
  1428 
  1429 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  1430 interface with 'setup' command instead.
  1431 
  1432 * Command 'local_setup' is similar to 'setup', but operates on a local
  1433 theory context.
  1434 
  1435 * The 'axiomatization' command now only works within a global theory
  1436 context.  INCOMPATIBILITY.
  1437 
  1438 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  1439 hypotheses.  Sorts required in the course of reasoning need to be
  1440 covered by the constraints in the initial statement, completed by the
  1441 type instance information of the background theory.  Non-trivial sort
  1442 hypotheses, which rarely occur in practice, may be specified via
  1443 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  1444 
  1445   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  1446 
  1447 The result contains an implicit sort hypotheses as before --
  1448 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  1449 normalization.
  1450 
  1451 * Generalized Isar history, with support for linear undo, direct state
  1452 addressing etc.
  1453 
  1454 * Changed defaults for unify configuration options:
  1455 
  1456   unify_trace_bound = 50 (formerly 25)
  1457   unify_search_bound = 60 (formerly 30)
  1458 
  1459 * Different bookkeeping for code equations (INCOMPATIBILITY):
  1460 
  1461   a) On theory merge, the last set of code equations for a particular
  1462      constant is taken (in accordance with the policy applied by other
  1463      parts of the code generator framework).
  1464 
  1465   b) Code equations stemming from explicit declarations (e.g. code
  1466      attribute) gain priority over default code equations stemming
  1467      from definition, primrec, fun etc.
  1468 
  1469 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  1470 
  1471 * Unified theorem tables for both code generators.  Thus [code
  1472 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  1473 
  1474 * Command 'find_consts' searches for constants based on type and name
  1475 patterns, e.g.
  1476 
  1477     find_consts "_ => bool"
  1478 
  1479 By default, matching is against subtypes, but it may be restricted to
  1480 the whole type.  Searching by name is possible.  Multiple queries are
  1481 conjunctive and queries may be negated by prefixing them with a
  1482 hyphen:
  1483 
  1484     find_consts strict: "_ => bool" name: "Int" -"int => int"
  1485 
  1486 * New 'find_theorems' criterion "solves" matches theorems that
  1487 directly solve the current goal (modulo higher-order unification).
  1488 
  1489 * Auto solve feature for main theorem statements: whenever a new goal
  1490 is stated, "find_theorems solves" is called; any theorems that could
  1491 solve the lemma directly are listed as part of the goal state.
  1492 Cf. associated options in Proof General Isabelle settings menu,
  1493 enabled by default, with reasonable timeout for pathological cases of
  1494 higher-order unification.
  1495 
  1496 
  1497 *** Document preparation ***
  1498 
  1499 * Antiquotation @{lemma} now imitates a regular terminal proof,
  1500 demanding keyword 'by' and supporting the full method expression
  1501 syntax just like the Isar command 'by'.
  1502 
  1503 
  1504 *** HOL ***
  1505 
  1506 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  1507 points Main and Complex_Main remain as before.
  1508 
  1509 * Logic image HOL-Plain provides a minimal HOL with the most important
  1510 tools available (inductive, datatype, primrec, ...).  This facilitates
  1511 experimentation and tool development.  Note that user applications
  1512 (and library theories) should never refer to anything below theory
  1513 Main, as before.
  1514 
  1515 * Logic image HOL-Main stops at theory Main, and thus facilitates
  1516 experimentation due to shorter build times.
  1517 
  1518 * Logic image HOL-NSA contains theories of nonstandard analysis which
  1519 were previously part of former HOL-Complex.  Entry point Hyperreal
  1520 remains valid, but theories formerly using Complex_Main should now use
  1521 new entry point Hypercomplex.
  1522 
  1523 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  1524 Posix processes.  Avoids potentially expensive forking of the ML
  1525 process.  New thread-based implementation also works on non-Unix
  1526 platforms (Cygwin).  Provers are no longer hardwired, but defined
  1527 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  1528 commands are covered in the isar-ref manual.
  1529 
  1530 * Wrapper scripts for remote SystemOnTPTP service allows to use
  1531 sledgehammer without local ATP installation (Vampire etc.). Other
  1532 provers may be included via suitable ML wrappers, see also
  1533 src/HOL/ATP_Linkup.thy.
  1534 
  1535 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  1536 menu.
  1537 
  1538 * The metis method no longer fails because the theorem is too trivial
  1539 (contains the empty clause).
  1540 
  1541 * The metis method now fails in the usual manner, rather than raising
  1542 an exception, if it determines that it cannot prove the theorem.
  1543 
  1544 * Method "coherent" implements a prover for coherent logic (see also
  1545 src/Tools/coherent.ML).
  1546 
  1547 * Constants "undefined" and "default" replace "arbitrary".  Usually
  1548 "undefined" is the right choice to replace "arbitrary", though
  1549 logically there is no difference.  INCOMPATIBILITY.
  1550 
  1551 * Command "value" now integrates different evaluation mechanisms.  The
  1552 result of the first successful evaluation mechanism is printed.  In
  1553 square brackets a particular named evaluation mechanisms may be
  1554 specified (currently, [SML], [code] or [nbe]).  See further
  1555 src/HOL/ex/Eval_Examples.thy.
  1556 
  1557 * Normalization by evaluation now allows non-leftlinear equations.
  1558 Declare with attribute [code nbe].
  1559 
  1560 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  1561 as the structured Isar versions "cases" and "induct", cf. the
  1562 corresponding "cases" and "induct" attributes.  Mutual induction rules
  1563 are now presented as a list of individual projections
  1564 (e.g. foo_bar.inducts for types foo and bar); the old format with
  1565 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  1566 rare situations a different rule is selected --- notably nested tuple
  1567 elimination instead of former prod.exhaust: use explicit (case_tac t
  1568 rule: prod.exhaust) here.
  1569 
  1570 * Attributes "cases", "induct", "coinduct" support "del" option.
  1571 
  1572 * Removed fact "case_split_thm", which duplicates "case_split".
  1573 
  1574 * The option datatype has been moved to a new theory Option.  Renamed
  1575 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  1576 
  1577 * New predicate "strict_mono" classifies strict functions on partial
  1578 orders.  With strict functions on linear orders, reasoning about
  1579 (in)equalities is facilitated by theorems "strict_mono_eq",
  1580 "strict_mono_less_eq" and "strict_mono_less".
  1581 
  1582 * Some set operations are now proper qualified constants with
  1583 authentic syntax.  INCOMPATIBILITY:
  1584 
  1585     op Int ~>   Set.Int
  1586     op Un ~>    Set.Un
  1587     INTER ~>    Set.INTER
  1588     UNION ~>    Set.UNION
  1589     Inter ~>    Set.Inter
  1590     Union ~>    Set.Union
  1591     {} ~>       Set.empty
  1592     UNIV ~>     Set.UNIV
  1593 
  1594 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  1595 theory Set.
  1596 
  1597 * Auxiliary class "itself" has disappeared -- classes without any
  1598 parameter are treated as expected by the 'class' command.
  1599 
  1600 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  1601 
  1602 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  1603 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  1604 
  1605 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  1606 method "approximation".  It proves formulas on real values by using
  1607 interval arithmetic.  In the formulas are also the transcendental
  1608 functions sin, cos, tan, atan, ln, exp and the constant pi are
  1609 allowed. For examples see
  1610 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  1611 
  1612 * Theory "Reflection" now resides in HOL/Library.
  1613 
  1614 * Entry point to Word library now simply named "Word".
  1615 INCOMPATIBILITY.
  1616 
  1617 * Made source layout more coherent with logical distribution
  1618 structure:
  1619 
  1620     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  1621     src/HOL/Library/Code_Message.thy ~> src/HOL/
  1622     src/HOL/Library/GCD.thy ~> src/HOL/
  1623     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  1624     src/HOL/Library/Parity.thy ~> src/HOL/
  1625     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  1626     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  1627     src/HOL/Real/Lubs.thy ~> src/HOL/
  1628     src/HOL/Real/PReal.thy ~> src/HOL/
  1629     src/HOL/Real/Rational.thy ~> src/HOL/
  1630     src/HOL/Real/RComplete.thy ~> src/HOL/
  1631     src/HOL/Real/RealDef.thy ~> src/HOL/
  1632     src/HOL/Real/RealPow.thy ~> src/HOL/
  1633     src/HOL/Real/Real.thy ~> src/HOL/
  1634     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  1635     src/HOL/Complex/Complex.thy ~> src/HOL/
  1636     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  1637     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  1638     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  1639     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  1640     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  1641     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  1642     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  1643     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  1644     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  1645     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  1646     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  1647     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  1648     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  1649     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  1650     src/HOL/Real/Float ~> src/HOL/Library/
  1651     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  1652     src/HOL/Real/RealVector.thy ~> src/HOL/
  1653 
  1654     src/HOL/arith_data.ML ~> src/HOL/Tools
  1655     src/HOL/hologic.ML ~> src/HOL/Tools
  1656     src/HOL/simpdata.ML ~> src/HOL/Tools
  1657     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  1658     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  1659     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  1660     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  1661     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  1662     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  1663     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  1664 
  1665     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  1666     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  1667     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  1668     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  1669     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  1670     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  1671 
  1672 * If methods "eval" and "evaluation" encounter a structured proof
  1673 state with !!/==>, only the conclusion is evaluated to True (if
  1674 possible), avoiding strange error messages.
  1675 
  1676 * Method "sizechange" automates termination proofs using (a
  1677 modification of) the size-change principle.  Requires SAT solver.  See
  1678 src/HOL/ex/Termination.thy for examples.
  1679 
  1680 * Simplifier: simproc for let expressions now unfolds if bound
  1681 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  1682 
  1683 * Method "arith": Linear arithmetic now ignores all inequalities when
  1684 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  1685 
  1686 * New attribute "arith" for facts that should always be used
  1687 automatically by arithmetic. It is intended to be used locally in
  1688 proofs, e.g.
  1689 
  1690   assumes [arith]: "x > 0"
  1691 
  1692 Global usage is discouraged because of possible performance impact.
  1693 
  1694 * New classes "top" and "bot" with corresponding operations "top" and
  1695 "bot" in theory Orderings; instantiation of class "complete_lattice"
  1696 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  1697 
  1698 * Changed definition lemma "less_fun_def" in order to provide an
  1699 instance for preorders on functions; use lemma "less_le" instead.
  1700 INCOMPATIBILITY.
  1701 
  1702 * Theory Orderings: class "wellorder" moved here, with explicit
  1703 induction rule "less_induct" as assumption.  For instantiation of
  1704 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  1705 INCOMPATIBILITY.
  1706 
  1707 * Theory Orderings: added class "preorder" as superclass of "order".
  1708 INCOMPATIBILITY: Instantiation proofs for order, linorder
  1709 etc. slightly changed.  Some theorems named order_class.* now named
  1710 preorder_class.*.
  1711 
  1712 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  1713 "diag" to "Id_on".
  1714 
  1715 * Theory Finite_Set: added a new fold combinator of type
  1716 
  1717   ('a => 'b => 'b) => 'b => 'a set => 'b
  1718 
  1719 Occasionally this is more convenient than the old fold combinator
  1720 which is now defined in terms of the new one and renamed to
  1721 fold_image.
  1722 
  1723 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  1724 and "ring_simps" have been replaced by "algebra_simps" (which can be
  1725 extended with further lemmas!).  At the moment both still exist but
  1726 the former will disappear at some point.
  1727 
  1728 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  1729 class recpower.  Type-specific simp rules for various recpower types
  1730 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  1731 
  1732 rat_power_0    -> power_0
  1733 rat_power_Suc  -> power_Suc
  1734 realpow_0      -> power_0
  1735 realpow_Suc    -> power_Suc
  1736 complexpow_0   -> power_0
  1737 complexpow_Suc -> power_Suc
  1738 power_poly_0   -> power_0
  1739 power_poly_Suc -> power_Suc
  1740 
  1741 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  1742 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  1743 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  1744 of lemmas from Divides has been generalized from nat to class
  1745 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  1746 renames resulting from duplicate elimination:
  1747 
  1748     dvd_def_mod ~>          dvd_eq_mod_eq_0
  1749     zero_dvd_iff ~>         dvd_0_left_iff
  1750     dvd_0 ~>                dvd_0_right
  1751     DIVISION_BY_ZERO_DIV ~> div_by_0
  1752     DIVISION_BY_ZERO_MOD ~> mod_by_0
  1753     mult_div ~>             div_mult_self2_is_id
  1754     mult_mod ~>             mod_mult_self2_is_0
  1755 
  1756 * Theory IntDiv: removed many lemmas that are instances of class-based
  1757 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  1758 rename old lemmas as follows:
  1759 
  1760 dvd_diff               -> nat_dvd_diff
  1761 dvd_zminus_iff         -> dvd_minus_iff
  1762 mod_add1_eq            -> mod_add_eq
  1763 mod_mult1_eq           -> mod_mult_right_eq
  1764 mod_mult1_eq'          -> mod_mult_left_eq
  1765 mod_mult_distrib_mod   -> mod_mult_eq
  1766 nat_mod_add_left_eq    -> mod_add_left_eq
  1767 nat_mod_add_right_eq   -> mod_add_right_eq
  1768 nat_mod_div_trivial    -> mod_div_trivial
  1769 nat_mod_mod_trivial    -> mod_mod_trivial
  1770 zdiv_zadd_self1        -> div_add_self1
  1771 zdiv_zadd_self2        -> div_add_self2
  1772 zdiv_zmult_self1       -> div_mult_self2_is_id
  1773 zdiv_zmult_self2       -> div_mult_self1_is_id
  1774 zdvd_triv_left         -> dvd_triv_left
  1775 zdvd_triv_right        -> dvd_triv_right
  1776 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  1777 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  1778 zmod_zadd_left_eq      -> mod_add_left_eq
  1779 zmod_zadd_right_eq     -> mod_add_right_eq
  1780 zmod_zadd_self1        -> mod_add_self1
  1781 zmod_zadd_self2        -> mod_add_self2
  1782 zmod_zadd1_eq          -> mod_add_eq
  1783 zmod_zdiff1_eq         -> mod_diff_eq
  1784 zmod_zdvd_zmod         -> mod_mod_cancel
  1785 zmod_zmod_cancel       -> mod_mod_cancel
  1786 zmod_zmult_self1       -> mod_mult_self2_is_0
  1787 zmod_zmult_self2       -> mod_mult_self1_is_0
  1788 zmod_1                 -> mod_by_1
  1789 zdiv_1                 -> div_by_1
  1790 zdvd_abs1              -> abs_dvd_iff
  1791 zdvd_abs2              -> dvd_abs_iff
  1792 zdvd_refl              -> dvd_refl
  1793 zdvd_trans             -> dvd_trans
  1794 zdvd_zadd              -> dvd_add
  1795 zdvd_zdiff             -> dvd_diff
  1796 zdvd_zminus_iff        -> dvd_minus_iff
  1797 zdvd_zminus2_iff       -> minus_dvd_iff
  1798 zdvd_zmultD            -> dvd_mult_right
  1799 zdvd_zmultD2           -> dvd_mult_left
  1800 zdvd_zmult_mono        -> mult_dvd_mono
  1801 zdvd_0_right           -> dvd_0_right
  1802 zdvd_0_left            -> dvd_0_left_iff
  1803 zdvd_1_left            -> one_dvd
  1804 zminus_dvd_iff         -> minus_dvd_iff
  1805 
  1806 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  1807 
  1808 * The real numbers offer decimal input syntax: 12.34 is translated
  1809 into 1234/10^2. This translation is not reversed upon output.
  1810 
  1811 * Theory Library/Polynomial defines an abstract type 'a poly of
  1812 univariate polynomials with coefficients of type 'a.  In addition to
  1813 the standard ring operations, it also supports div and mod.  Code
  1814 generation is also supported, using list-style constructors.
  1815 
  1816 * Theory Library/Inner_Product defines a class of real_inner for real
  1817 inner product spaces, with an overloaded operation inner :: 'a => 'a
  1818 => real.  Class real_inner is a subclass of real_normed_vector from
  1819 theory RealVector.
  1820 
  1821 * Theory Library/Product_Vector provides instances for the product
  1822 type 'a * 'b of several classes from RealVector and Inner_Product.
  1823 Definitions of addition, subtraction, scalar multiplication, norms,
  1824 and inner products are included.
  1825 
  1826 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  1827 addition to the field operations, numerals and case syntax are also
  1828 supported.
  1829 
  1830 * Theory Library/Diagonalize provides constructive version of Cantor's
  1831 first diagonalization argument.
  1832 
  1833 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  1834 zlcm (for int); carried together from various gcd/lcm developements in
  1835 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  1836 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  1837 may recover tupled syntax as follows:
  1838 
  1839     hide (open) const gcd
  1840     abbreviation gcd where
  1841       "gcd == (%(a, b). GCD.gcd a b)"
  1842     notation (output)
  1843       GCD.gcd ("gcd '(_, _')")
  1844 
  1845 The same works for lcm, zgcd, zlcm.
  1846 
  1847 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  1848 instantiations for algebraic structures.  Removed some duplicate
  1849 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  1850 
  1851 * ML antiquotation @{code} takes a constant as argument and generates
  1852 corresponding code in background and inserts name of the corresponding
  1853 resulting ML value/function/datatype constructor binding in place.
  1854 All occurrences of @{code} with a single ML block are generated
  1855 simultaneously.  Provides a generic and safe interface for
  1856 instrumentalizing code generation.  See
  1857 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  1858 In future you ought to refrain from ad-hoc compiling generated SML
  1859 code on the ML toplevel.  Note that (for technical reasons) @{code}
  1860 cannot refer to constants for which user-defined serializations are
  1861 set.  Refer to the corresponding ML counterpart directly in that
  1862 cases.
  1863 
  1864 * Command 'rep_datatype': instead of theorem names the command now
  1865 takes a list of terms denoting the constructors of the type to be
  1866 represented as datatype.  The characteristic theorems have to be
  1867 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  1868 have disappeared in favour of existing ones:
  1869 
  1870     unit_induct                 ~> unit.induct
  1871     prod_induct                 ~> prod.induct
  1872     sum_induct                  ~> sum.induct
  1873     Suc_Suc_eq                  ~> nat.inject
  1874     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  1875 
  1876 
  1877 *** HOL-Algebra ***
  1878 
  1879 * New locales for orders and lattices where the equivalence relation
  1880 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  1881 locales use a record structure with field eq for the equivalence.
  1882 
  1883 * New theory of factorial domains.
  1884 
  1885 * Units_l_inv and Units_r_inv are now simp rules by default.
  1886 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  1887 and/or r_inv will now also require deletion of these lemmas.
  1888 
  1889 * Renamed the following theorems, INCOMPATIBILITY:
  1890 
  1891 UpperD ~> Upper_memD
  1892 LowerD ~> Lower_memD
  1893 least_carrier ~> least_closed
  1894 greatest_carrier ~> greatest_closed
  1895 greatest_Lower_above ~> greatest_Lower_below
  1896 one_zero ~> carrier_one_zero
  1897 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  1898 
  1899 
  1900 *** HOL-Nominal ***
  1901 
  1902 * Nominal datatypes can now contain type-variables.
  1903 
  1904 * Commands 'nominal_inductive' and 'equivariance' work with local
  1905 theory targets.
  1906 
  1907 * Nominal primrec can now works with local theory targets and its
  1908 specification syntax now conforms to the general format as seen in
  1909 'inductive' etc.
  1910 
  1911 * Method "perm_simp" honours the standard simplifier attributes
  1912 (no_asm), (no_asm_use) etc.
  1913 
  1914 * The new predicate #* is defined like freshness, except that on the
  1915 left hand side can be a set or list of atoms.
  1916 
  1917 * Experimental command 'nominal_inductive2' derives strong induction
  1918 principles for inductive definitions.  In contrast to
  1919 'nominal_inductive', which can only deal with a fixed number of
  1920 binders, it can deal with arbitrary expressions standing for sets of
  1921 atoms to be avoided.  The only inductive definition we have at the
  1922 moment that needs this generalisation is the typing rule for Lets in
  1923 the algorithm W:
  1924 
  1925  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  1926  -----------------------------------------------------------------
  1927          Gamma |- Let x be t1 in t2 : T2
  1928 
  1929 In this rule one wants to avoid all the binders that are introduced by
  1930 "close Gamma T1".  We are looking for other examples where this
  1931 feature might be useful.  Please let us know.
  1932 
  1933 
  1934 *** HOLCF ***
  1935 
  1936 * Reimplemented the simplification procedure for proving continuity
  1937 subgoals.  The new simproc is extensible; users can declare additional
  1938 continuity introduction rules with the attribute [cont2cont].
  1939 
  1940 * The continuity simproc now uses a different introduction rule for
  1941 solving continuity subgoals on terms with lambda abstractions.  In
  1942 some rare cases the new simproc may fail to solve subgoals that the
  1943 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  1944 Potential INCOMPATIBILITY.
  1945 
  1946 * Command 'fixrec': specification syntax now conforms to the general
  1947 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  1948 examples.  INCOMPATIBILITY.
  1949 
  1950 
  1951 *** ZF ***
  1952 
  1953 * Proof of Zorn's Lemma for partial orders.
  1954 
  1955 
  1956 *** ML ***
  1957 
  1958 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  1959 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  1960 depends on multithreading, so timouts will not work before Poly/ML
  1961 5.2.1!
  1962 
  1963 * High-level support for concurrent ML programming, see
  1964 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  1965 particularly convenient to organize independent functional
  1966 computations.  The concept of "synchronized variables" provides a
  1967 higher-order interface for components with shared state, avoiding the
  1968 delicate details of mutexes and condition variables.  (Requires
  1969 Poly/ML 5.2.1 or later.)
  1970 
  1971 * ML bindings produced via Isar commands are stored within the Isar
  1972 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  1973 become thread-safe and work with undo as expected (concerning
  1974 top-level bindings, not side-effects on global references).
  1975 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  1976 compiler at runtime; really global bindings need to be given outside a
  1977 theory.  (Requires Poly/ML 5.2 or later.)
  1978 
  1979 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  1980 context.  Top-level ML bindings are stored within the proof context in
  1981 a purely sequential fashion, disregarding the nested proof structure.
  1982 ML bindings introduced by 'ML_prf' are discarded at the end of the
  1983 proof.  (Requires Poly/ML 5.2 or later.)
  1984 
  1985 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  1986 and Method.setup, as well as Isar commands 'attribute_setup' and
  1987 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  1988 existing code accordingly, or use plain 'setup' together with old
  1989 Method.add_method.
  1990 
  1991 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  1992 to 'a -> thm, while results are always tagged with an authentic oracle
  1993 name.  The Isar command 'oracle' is now polymorphic, no argument type
  1994 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  1995 accordingly.  Note that extra performance may be gained by producing
  1996 the cterm carefully, avoiding slow Thm.cterm_of.
  1997 
  1998 * Simplified interface for defining document antiquotations via
  1999 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2000 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2001 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2002 examples.
  2003 
  2004 * More systematic treatment of long names, abstract name bindings, and
  2005 name space operations.  Basic operations on qualified names have been
  2006 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2007 Long_Name.append.  Old type bstring has been mostly replaced by
  2008 abstract type binding (see structure Binding), which supports precise
  2009 qualification by packages and local theory targets, as well as proper
  2010 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2011 bstring values into Binding.name, or better pass through abstract
  2012 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2013 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2014 
  2015 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2016 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2017 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2018 
  2019 * Disposed old type and term read functions (Sign.read_def_typ,
  2020 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2021 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2022 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2023 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2024 resort for legacy applications.
  2025 
  2026 * Disposed old declarations, tactics, tactic combinators that refer to
  2027 the simpset or claset of an implicit theory (such as Addsimps,
  2028 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2029 embedded ML text, or local_simpset_of with a proper context passed as
  2030 explicit runtime argument.
  2031 
  2032 * Rules and tactics that read instantiations (read_instantiate,
  2033 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2034 context, which is required for parsing and type-checking.  Moreover,
  2035 the variables are specified as plain indexnames, not string encodings
  2036 thereof.  INCOMPATIBILITY.
  2037 
  2038 * Generic Toplevel.add_hook interface allows to analyze the result of
  2039 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2040 for theorem dependency output of transactions resulting in a new
  2041 theory state.
  2042 
  2043 * ML antiquotations: block-structured compilation context indicated by
  2044 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2045 
  2046   @{binding name}                         - basic name binding
  2047   @{let ?pat = term}                      - term abbreviation (HO matching)
  2048   @{note name = fact}                     - fact abbreviation
  2049   @{thm fact}                             - singleton fact (with attributes)
  2050   @{thms fact}                            - general fact (with attributes)
  2051   @{lemma prop by method}                 - singleton goal
  2052   @{lemma prop by meth1 meth2}            - singleton goal
  2053   @{lemma prop1 ... propN by method}      - general goal
  2054   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2055   @{lemma (open) ...}                     - open derivation
  2056 
  2057 
  2058 *** System ***
  2059 
  2060 * The Isabelle "emacs" tool provides a specific interface to invoke
  2061 Proof General / Emacs, with more explicit failure if that is not
  2062 installed (the old isabelle-interface script silently falls back on
  2063 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2064 installation location of the Proof General distribution.
  2065 
  2066 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2067 the Isabelle process into a JVM/Scala application.  See
  2068 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2069 process wrapper has been discontinued.)
  2070 
  2071 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2072 
  2073 * Various status messages (with exact source position information) are
  2074 emitted, if proper markup print mode is enabled.  This allows
  2075 user-interface components to provide detailed feedback on internal
  2076 prover operations.
  2077 
  2078 
  2079 
  2080 New in Isabelle2008 (June 2008)
  2081 -------------------------------
  2082 
  2083 *** General ***
  2084 
  2085 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2086 and updated, with formally checked references as hyperlinks.
  2087 
  2088 * Theory loader: use_thy (and similar operations) no longer set the
  2089 implicit ML context, which was occasionally hard to predict and in
  2090 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2091 provides a proper context already.
  2092 
  2093 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2094 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2095 'use' within a theory file will do the job.
  2096 
  2097 * Name space merge now observes canonical order, i.e. the second space
  2098 is inserted into the first one, while existing entries in the first
  2099 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2100 swap theory imports.
  2101 
  2102 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2103 INCOMPATIBILITY in identifier syntax etc.
  2104 
  2105 * Outer syntax: string tokens no longer admit escaped white space,
  2106 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2107 white space without escapes.
  2108 
  2109 * Outer syntax: string tokens may contain arbitrary character codes
  2110 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2111 "foo_bar".
  2112 
  2113 
  2114 *** Pure ***
  2115 
  2116 * Context-dependent token translations.  Default setup reverts locally
  2117 fixed variables, and adds hilite markup for undeclared frees.
  2118 
  2119 * Unused theorems can be found using the new command 'unused_thms'.
  2120 There are three ways of invoking it:
  2121 
  2122 (1) unused_thms
  2123      Only finds unused theorems in the current theory.
  2124 
  2125 (2) unused_thms thy_1 ... thy_n -
  2126      Finds unused theorems in the current theory and all of its ancestors,
  2127      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2128 
  2129 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2130      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2131      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2132      their ancestors.
  2133 
  2134 In order to increase the readability of the list produced by
  2135 unused_thms, theorems that have been created by a particular instance
  2136 of a theory command such as 'inductive' or 'function' are considered
  2137 to belong to the same "group", meaning that if at least one theorem in
  2138 this group is used, the other theorems in the same group are no longer
  2139 reported as unused.  Moreover, if all theorems in the group are
  2140 unused, only one theorem in the group is displayed.
  2141 
  2142 Note that proof objects have to be switched on in order for
  2143 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2144 usually the case when using Proof General with the default settings).
  2145 
  2146 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2147 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2148 duplicate fact bindings, or even accidental fact duplications.  Note
  2149 that tools may maintain dynamically scoped facts systematically, using
  2150 PureThy.add_thms_dynamic.
  2151 
  2152 * Command 'hide' now allows to hide from "fact" name space as well.
  2153 
  2154 * Eliminated destructive theorem database, simpset, claset, and
  2155 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2156 update of theories within ML code.
  2157 
  2158 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2159 INCOMPATIBILITY, object-logics depending on former Pure require
  2160 additional setup PureThy.old_appl_syntax_setup; object-logics
  2161 depending on former CPure need to refer to Pure.
  2162 
  2163 * Commands 'use' and 'ML' are now purely functional, operating on
  2164 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2165 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2166 INCOMPATIBILITY.
  2167 
  2168 * Command 'setup': discontinued implicit version with ML reference.
  2169 
  2170 * Instantiation target allows for simultaneous specification of class
  2171 instance operations together with an instantiation proof.
  2172 Type-checking phase allows to refer to class operations uniformly.
  2173 See src/HOL/Complex/Complex.thy for an Isar example and
  2174 src/HOL/Library/Eval.thy for an ML example.
  2175 
  2176 * Indexing of literal facts: be more serious about including only
  2177 facts from the visible specification/proof context, but not the
  2178 background context (locale etc.).  Affects `prop` notation and method
  2179 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2180 situations.
  2181 
  2182 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2183 "(open)" option, which used to expose internal bound variables to the
  2184 proof text.
  2185 
  2186 * Isar statements: removed obsolete case "rule_context".
  2187 INCOMPATIBILITY, better use explicit fixes/assumes.
  2188 
  2189 * Locale proofs: default proof step now includes 'unfold_locales';
  2190 hence 'proof' without argument may be used to unfold locale
  2191 predicates.
  2192 
  2193 
  2194 *** Document preparation ***
  2195 
  2196 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2197 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2198 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2199 spot); renamed link color from "darkblue" to "linkcolor" (default
  2200 value unchanged, can be redefined via \definecolor); no longer sets
  2201 "a4paper" option (unnecessary or even intrusive).
  2202 
  2203 * Antiquotation @{lemma A method} proves proposition A by the given
  2204 method (either a method name or a method name plus (optional) method
  2205 arguments in parentheses) and prints A just like @{prop A}.
  2206 
  2207 
  2208 *** HOL ***
  2209 
  2210 * New primrec package.  Specification syntax conforms in style to
  2211 definition/function/....  No separate induction rule is provided.  The
  2212 "primrec" command distinguishes old-style and new-style specifications
  2213 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2214 When adjusting theories, beware: constants stemming from new-style
  2215 primrec specifications have authentic syntax.
  2216 
  2217 * Metis prover is now an order of magnitude faster, and also works
  2218 with multithreading.
  2219 
  2220 * Metis: the maximum number of clauses that can be produced from a
  2221 theorem is now given by the attribute max_clauses.  Theorems that
  2222 exceed this number are ignored, with a warning printed.
  2223 
  2224 * Sledgehammer no longer produces structured proofs by default. To
  2225 enable, declare [[sledgehammer_full = true]].  Attributes
  2226 reconstruction_modulus, reconstruction_sorts renamed
  2227 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2228 
  2229 * Method "induct_scheme" derives user-specified induction rules
  2230 from well-founded induction and completeness of patterns. This factors
  2231 out some operations that are done internally by the function package
  2232 and makes them available separately.  See
  2233 src/HOL/ex/Induction_Scheme.thy for examples.
  2234 
  2235 * More flexible generation of measure functions for termination
  2236 proofs: Measure functions can be declared by proving a rule of the
  2237 form "is_measure f" and giving it the [measure_function] attribute.
  2238 The "is_measure" predicate is logically meaningless (always true), and
  2239 just guides the heuristic.  To find suitable measure functions, the
  2240 termination prover sets up the goal "is_measure ?f" of the appropriate
  2241 type and generates all solutions by prolog-style backwards proof using
  2242 the declared rules.
  2243 
  2244 This setup also deals with rules like 
  2245 
  2246   "is_measure f ==> is_measure (list_size f)"
  2247 
  2248 which accommodates nested datatypes that recurse through lists.
  2249 Similar rules are predeclared for products and option types.
  2250 
  2251 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2252 
  2253   INCOMPATIBILITIES:
  2254 
  2255   - Definitions of overloaded constants on sets have to be replaced by
  2256     definitions on => and bool.
  2257 
  2258   - Some definitions of overloaded operators on sets can now be proved
  2259     using the definitions of the operators on => and bool.  Therefore,
  2260     the following theorems have been renamed:
  2261 
  2262       subset_def   -> subset_eq
  2263       psubset_def  -> psubset_eq
  2264       set_diff_def -> set_diff_eq
  2265       Compl_def    -> Compl_eq
  2266       Sup_set_def  -> Sup_set_eq
  2267       Inf_set_def  -> Inf_set_eq
  2268       sup_set_def  -> sup_set_eq
  2269       inf_set_def  -> inf_set_eq
  2270 
  2271   - Due to the incompleteness of the HO unification algorithm, some
  2272     rules such as subst may require manual instantiation, if some of
  2273     the unknowns in the rule is a set.
  2274 
  2275   - Higher order unification and forward proofs:
  2276     The proof pattern
  2277 
  2278       have "P (S::'a set)" <...>
  2279       then have "EX S. P S" ..
  2280 
  2281     no longer works (due to the incompleteness of the HO unification
  2282     algorithm) and must be replaced by the pattern
  2283 
  2284       have "EX S. P S"
  2285       proof
  2286         show "P S" <...>
  2287       qed
  2288 
  2289   - Calculational reasoning with subst (or similar rules):
  2290     The proof pattern
  2291 
  2292       have "P (S::'a set)" <...>
  2293       also have "S = T" <...>
  2294       finally have "P T" .
  2295 
  2296     no longer works (for similar reasons as the previous example) and
  2297     must be replaced by something like
  2298 
  2299       have "P (S::'a set)" <...>
  2300       moreover have "S = T" <...>
  2301       ultimately have "P T" by simp
  2302 
  2303   - Tactics or packages written in ML code:
  2304     Code performing pattern matching on types via
  2305 
  2306       Type ("set", [T]) => ...
  2307 
  2308     must be rewritten. Moreover, functions like strip_type or
  2309     binder_types no longer return the right value when applied to a
  2310     type of the form
  2311 
  2312       T1 => ... => Tn => U => bool
  2313 
  2314     rather than
  2315 
  2316       T1 => ... => Tn => U set
  2317 
  2318 * Merged theories Wellfounded_Recursion, Accessible_Part and
  2319 Wellfounded_Relations to theory Wellfounded.
  2320 
  2321 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  2322 
  2323 * Class finite no longer treats UNIV as class parameter.  Use class
  2324 enum from theory Library/Enum instead to achieve a similar effect.
  2325 INCOMPATIBILITY.
  2326 
  2327 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  2328 and "Cons".  INCOMPATIBILITY.
  2329 
  2330 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  2331 Potential INCOMPATIBILITY.
  2332 
  2333 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  2334 injective_fst_snd removed, use split_eta and prod_eqI instead.
  2335 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  2336 
  2337 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  2338 the same name in theory Orderings:
  2339 
  2340   less_trans
  2341   less_linear
  2342   le_imp_less_or_eq
  2343   le_less_trans
  2344   less_le_trans
  2345   less_not_sym
  2346   less_asym
  2347 
  2348 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  2349 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  2350 and different variable names.
  2351 
  2352 * Library/Option_ord.thy: Canonical order on option type.
  2353 
  2354 * Library/RBT.thy: Red-black trees, an efficient implementation of
  2355 finite maps.
  2356 
  2357 * Library/Countable.thy: Type class for countable types.
  2358 
  2359 * Theory Int: The representation of numerals has changed.  The infix
  2360 operator BIT and the bit datatype with constructors B0 and B1 have
  2361 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  2362 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  2363 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  2364 accordingly.
  2365 
  2366 * Theory Nat: definition of <= and < on natural numbers no longer
  2367 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  2368 le_def and less_def have disappeared.  Consider lemmas not_less
  2369 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  2370 
  2371 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  2372 (whose purpose mainly is for various fold_set functionals) have been
  2373 abandoned in favor of the existing algebraic classes
  2374 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  2375 lower_semilattice (resp. upper_semilattice) and linorder.
  2376 INCOMPATIBILITY.
  2377 
  2378 * Theory Transitive_Closure: induct and cases rules now declare proper
  2379 case_names ("base" and "step").  INCOMPATIBILITY.
  2380 
  2381 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  2382 lattices.  The form set-specific version is available as
  2383 Inductive.lfp_ordinal_induct_set.
  2384 
  2385 * Renamed theorems "power.simps" to "power_int.simps".
  2386 INCOMPATIBILITY.
  2387 
  2388 * Class semiring_div provides basic abstract properties of semirings
  2389 with division and modulo operations.  Subsumes former class dvd_mod.
  2390 
  2391 * Merged theories IntDef, Numeral and IntArith into unified theory
  2392 Int.  INCOMPATIBILITY.
  2393 
  2394 * Theory Library/Code_Index: type "index" now represents natural
  2395 numbers rather than integers.  INCOMPATIBILITY.
  2396 
  2397 * New class "uminus" with operation "uminus" (split of from class
  2398 "minus" which now only has operation "minus", binary).
  2399 INCOMPATIBILITY.
  2400 
  2401 * Constants "card", "internal_split", "option_map" now with authentic
  2402 syntax.  INCOMPATIBILITY.
  2403 
  2404 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  2405 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  2406 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  2407 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  2408 Sup_set_def, le_def, less_def, option_map_def now with object
  2409 equality.  INCOMPATIBILITY.
  2410 
  2411 * Records. Removed K_record, and replaced it by pure lambda term
  2412 %x. c. The simplifier setup is now more robust against eta expansion.
  2413 INCOMPATIBILITY: in cases explicitly referring to K_record.
  2414 
  2415 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  2416 
  2417 * Library/ListVector: new theory of arithmetic vector operations.
  2418 
  2419 * Library/Order_Relation: new theory of various orderings as sets of
  2420 pairs.  Defines preorders, partial orders, linear orders and
  2421 well-orders on sets and on types.
  2422 
  2423 
  2424 *** ZF ***
  2425 
  2426 * Renamed some theories to allow to loading both ZF and HOL in the
  2427 same session:
  2428 
  2429   Datatype  -> Datatype_ZF
  2430   Inductive -> Inductive_ZF
  2431   Int       -> Int_ZF
  2432   IntDiv    -> IntDiv_ZF
  2433   Nat       -> Nat_ZF
  2434   List      -> List_ZF
  2435   Main      -> Main_ZF
  2436 
  2437 INCOMPATIBILITY: ZF theories that import individual theories below
  2438 Main might need to be adapted.  Regular theory Main is still
  2439 available, as trivial extension of Main_ZF.
  2440 
  2441 
  2442 *** ML ***
  2443 
  2444 * ML within Isar: antiquotation @{const name} or @{const
  2445 name(typargs)} produces statically-checked Const term.
  2446 
  2447 * Functor NamedThmsFun: data is available to the user as dynamic fact
  2448 (of the same name).  Removed obsolete print command.
  2449 
  2450 * Removed obsolete "use_legacy_bindings" function.
  2451 
  2452 * The ``print mode'' is now a thread-local value derived from a global
  2453 template (the former print_mode reference), thus access becomes
  2454 non-critical.  The global print_mode reference is for session
  2455 management only; user-code should use print_mode_value,
  2456 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  2457 
  2458 * Functions system/system_out provide a robust way to invoke external
  2459 shell commands, with propagation of interrupts (requires Poly/ML
  2460 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  2461 
  2462 
  2463 *** System ***
  2464 
  2465 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  2466 in accordance with Proof General 3.7, which prefers GNU emacs.
  2467 
  2468 * isatool tty runs Isabelle process with plain tty interaction;
  2469 optional line editor may be specified via ISABELLE_LINE_EDITOR
  2470 setting, the default settings attempt to locate "ledit" and "rlwrap".
  2471 
  2472 * isatool browser now works with Cygwin as well, using general
  2473 "javapath" function defined in Isabelle process environment.
  2474 
  2475 * YXML notation provides a simple and efficient alternative to
  2476 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  2477 isatool yxml as described in the Isabelle system manual.
  2478 
  2479 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  2480 provides general wrapper for managing an Isabelle process in a robust
  2481 fashion, with ``cooked'' output from stdin/stderr.
  2482 
  2483 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  2484 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  2485 
  2486 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  2487 way of changing the user's settings is via
  2488 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  2489 script.
  2490 
  2491 * Multithreading.max_threads := 0 refers to the number of actual CPU
  2492 cores of the underlying machine, which is a good starting point for
  2493 optimal performance tuning.  The corresponding usedir option -M allows
  2494 "max" as an alias for "0".  WARNING: does not work on certain versions
  2495 of Mac OS (with Poly/ML 5.1).
  2496 
  2497 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  2498 adverse effect of Isabelle flooding interactive front-ends (notably
  2499 ProofGeneral / XEmacs).
  2500 
  2501 
  2502 
  2503 New in Isabelle2007 (November 2007)
  2504 -----------------------------------
  2505 
  2506 *** General ***
  2507 
  2508 * More uniform information about legacy features, notably a
  2509 warning/error of "Legacy feature: ...", depending on the state of the
  2510 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  2511 legacy features will disappear eventually.
  2512 
  2513 * Theory syntax: the header format ``theory A = B + C:'' has been
  2514 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  2515 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  2516 
  2517 * Theory syntax: the old non-Isar theory file format has been
  2518 discontinued altogether.  Note that ML proof scripts may still be used
  2519 with Isar theories; migration is usually quite simple with the ML
  2520 function use_legacy_bindings.  INCOMPATIBILITY.
  2521 
  2522 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  2523 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  2524 quotes.
  2525 
  2526 * Theory loader: be more serious about observing the static theory
  2527 header specifications (including optional directories), but not the
  2528 accidental file locations of previously successful loads.  The strict
  2529 update policy of former update_thy is now already performed by
  2530 use_thy, so the former has been removed; use_thys updates several
  2531 theories simultaneously, just as 'imports' within a theory header
  2532 specification, but without merging the results.  Potential
  2533 INCOMPATIBILITY: may need to refine theory headers and commands
  2534 ROOT.ML which depend on load order.
  2535 
  2536 * Theory loader: optional support for content-based file
  2537 identification, instead of the traditional scheme of full physical
  2538 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  2539 (cf. the system manual).  The new scheme allows to work with
  2540 non-finished theories in persistent session images, such that source
  2541 files may be moved later on without requiring reloads.
  2542 
  2543 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2544 file (with the same base name as the theory) are considered a legacy
  2545 feature, which will disappear eventually. Even now, the theory loader
  2546 no longer maintains dependencies on such files.
  2547 
  2548 * Syntax: the scope for resolving ambiguities via type-inference is
  2549 now limited to individual terms, instead of whole simultaneous
  2550 specifications as before. This greatly reduces the complexity of the
  2551 syntax module and improves flexibility by separating parsing and
  2552 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  2553 'fixes' etc.) are required in rare situations.
  2554 
  2555 * Syntax: constants introduced by new-style packages ('definition',
  2556 'abbreviation' etc.) are passed through the syntax module in
  2557 ``authentic mode''. This means that associated mixfix annotations
  2558 really stick to such constants, independently of potential name space
  2559 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  2560 trees are represented slightly differently, may need to adapt syntax
  2561 translations accordingly. Use CONST marker in 'translations' and
  2562 @{const_syntax} antiquotation in 'parse_translation' etc.
  2563 
  2564 * Legacy goal package: reduced interface to the bare minimum required
  2565 to keep existing proof scripts running.  Most other user-level
  2566 functions are now part of the OldGoals structure, which is *not* open
  2567 by default (consider isatool expandshort before open OldGoals).
  2568 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  2569 these tend to cause confusion about the actual goal (!) context being
  2570 used here, which is not necessarily the same as the_context().
  2571 
  2572 * Command 'find_theorems': supports "*" wild-card in "name:"
  2573 criterion; "with_dups" option.  Certain ProofGeneral versions might
  2574 support a specific search form (see ProofGeneral/CHANGES).
  2575 
  2576 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  2577 by default, which means that "prems" (and also "fixed variables") are
  2578 suppressed from proof state output.  Note that the ProofGeneral
  2579 settings mechanism allows to change and save options persistently, but
  2580 older versions of Isabelle will fail to start up if a negative prems
  2581 limit is imposed.
  2582 
  2583 * Local theory targets may be specified by non-nested blocks of
  2584 ``context/locale/class ... begin'' followed by ``end''.  The body may
  2585 contain definitions, theorems etc., including any derived mechanism
  2586 that has been implemented on top of these primitives.  This concept
  2587 generalizes the existing ``theorem (in ...)'' towards more versatility
  2588 and scalability.
  2589 
  2590 * Proof General interface: proper undo of final 'end' command;
  2591 discontinued Isabelle/classic mode (ML proof scripts).
  2592 
  2593 
  2594 *** Document preparation ***
  2595 
  2596 * Added antiquotation @{theory name} which prints the given name,
  2597 after checking that it refers to a valid ancestor theory in the
  2598 current context.
  2599 
  2600 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  2601 check the given source text as ML type/structure, printing verbatim.
  2602 
  2603 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  2604 "c args == rhs" given in the current context.  (Any number of
  2605 arguments may be given on the LHS.)
  2606 
  2607 
  2608 *** Pure ***
  2609 
  2610 * The 'class' package offers a combination of axclass and locale to
  2611 achieve Haskell-like type classes in Isabelle.  Definitions and
  2612 theorems within a class context produce both relative results (with
  2613 implicit parameters according to the locale context), and polymorphic
  2614 constants with qualified polymorphism (according to the class
  2615 context).  Within the body context of a 'class' target, a separate
  2616 syntax layer ("user space type system") takes care of converting
  2617 between global polymorphic consts and internal locale representation.
  2618 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  2619 "isatool doc classes" provides a tutorial.
  2620 
  2621 * Generic code generator framework allows to generate executable
  2622 code for ML and Haskell (including Isabelle classes).  A short usage
  2623 sketch:
  2624 
  2625     internal compilation:
  2626         export_code <list of constants (term syntax)> in SML
  2627     writing SML code to a file:
  2628         export_code <list of constants (term syntax)> in SML <filename>
  2629     writing OCaml code to a file:
  2630         export_code <list of constants (term syntax)> in OCaml <filename>
  2631     writing Haskell code to a bunch of files:
  2632         export_code <list of constants (term syntax)> in Haskell <filename>
  2633 
  2634     evaluating closed propositions to True/False using code generation:
  2635         method ``eval''
  2636 
  2637 Reasonable default setup of framework in HOL.
  2638 
  2639 Theorem attributs for selecting and transforming function equations theorems:
  2640 
  2641     [code fun]:        select a theorem as function equation for a specific constant
  2642     [code fun del]:    deselect a theorem as function equation for a specific constant
  2643     [code inline]:     select an equation theorem for unfolding (inlining) in place
  2644     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  2645 
  2646 User-defined serializations (target in {SML, OCaml, Haskell}):
  2647 
  2648     code_const <and-list of constants (term syntax)>
  2649       {(target) <and-list of const target syntax>}+
  2650 
  2651     code_type <and-list of type constructors>
  2652       {(target) <and-list of type target syntax>}+
  2653 
  2654     code_instance <and-list of instances>
  2655       {(target)}+
  2656         where instance ::= <type constructor> :: <class>
  2657 
  2658     code_class <and_list of classes>
  2659       {(target) <and-list of class target syntax>}+
  2660         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  2661 
  2662 code_instance and code_class only are effective to target Haskell.
  2663 
  2664 For example usage see src/HOL/ex/Codegenerator.thy and
  2665 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  2666 generation from Isabelle/HOL theories is available via "isatool doc
  2667 codegen".
  2668 
  2669 * Code generator: consts in 'consts_code' Isar commands are now
  2670 referred to by usual term syntax (including optional type
  2671 annotations).
  2672 
  2673 * Command 'no_translations' removes translation rules from theory
  2674 syntax.
  2675 
  2676 * Overloaded definitions are now actually checked for acyclic
  2677 dependencies.  The overloading scheme is slightly more general than
  2678 that of Haskell98, although Isabelle does not demand an exact
  2679 correspondence to type class and instance declarations.
  2680 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  2681 exotic versions of overloading -- at the discretion of the user!
  2682 
  2683 Polymorphic constants are represented via type arguments, i.e. the
  2684 instantiation that matches an instance against the most general
  2685 declaration given in the signature.  For example, with the declaration
  2686 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  2687 as c(nat).  Overloading is essentially simultaneous structural
  2688 recursion over such type arguments.  Incomplete specification patterns
  2689 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  2690 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  2691 Command 'print_theory' outputs the normalized system of recursive
  2692 equations, see section "definitions".
  2693 
  2694 * Configuration options are maintained within the theory or proof
  2695 context (with name and type bool/int/string), providing a very simple
  2696 interface to a poor-man's version of general context data.  Tools may
  2697 declare options in ML (e.g. using Attrib.config_int) and then refer to
  2698 these values using Config.get etc.  Users may change options via an
  2699 associated attribute of the same name.  This form of context
  2700 declaration works particularly well with commands 'declare' or
  2701 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  2702 very easy to avoid global references, which would not observe Isar
  2703 toplevel undo/redo and fail to work with multithreading.
  2704 
  2705 Various global ML references of Pure and HOL have been turned into
  2706 configuration options:
  2707 
  2708   Unify.search_bound		unify_search_bound
  2709   Unify.trace_bound		unify_trace_bound
  2710   Unify.trace_simp		unify_trace_simp
  2711   Unify.trace_types		unify_trace_types
  2712   Simplifier.simp_depth_limit	simp_depth_limit
  2713   Blast.depth_limit		blast_depth_limit
  2714   DatatypeProp.dtK		datatype_distinctness_limit
  2715   fast_arith_neq_limit  	fast_arith_neq_limit
  2716   fast_arith_split_limit	fast_arith_split_limit
  2717 
  2718 * Named collections of theorems may be easily installed as context
  2719 data using the functor NamedThmsFun (see also
  2720 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  2721 attributes; there is also a toplevel print command.  This facility is
  2722 just a common case of general context data, which is the preferred way
  2723 for anything more complex than just a list of facts in canonical
  2724 order.
  2725 
  2726 * Isar: command 'declaration' augments a local theory by generic
  2727 declaration functions written in ML.  This enables arbitrary content
  2728 being added to the context, depending on a morphism that tells the
  2729 difference of the original declaration context wrt. the application
  2730 context encountered later on.
  2731 
  2732 * Isar: proper interfaces for simplification procedures.  Command
  2733 'simproc_setup' declares named simprocs (with match patterns, and body
  2734 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  2735 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  2736 
  2737 * Isar: an extra pair of brackets around attribute declarations
  2738 abbreviates a theorem reference involving an internal dummy fact,
  2739 which will be ignored later --- only the effect of the attribute on
  2740 the background context will persist.  This form of in-place
  2741 declarations is particularly useful with commands like 'declare' and
  2742 'using', for example ``have A using [[simproc a]] by simp''.
  2743 
  2744 * Isar: method "assumption" (and implicit closing of subproofs) now
  2745 takes simple non-atomic goal assumptions into account: after applying
  2746 an assumption as a rule the resulting subgoals are solved by atomic
  2747 assumption steps.  This is particularly useful to finish 'obtain'
  2748 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  2749 without referring to the original premise "!!x. P x ==> thesis" in the
  2750 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  2751 more permissive.
  2752 
  2753 * Isar: implicit use of prems from the Isar proof context is
  2754 considered a legacy feature.  Common applications like ``have A .''
  2755 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  2756 referencing facts explicitly here improves readability and
  2757 maintainability of proof texts.
  2758 
  2759 * Isar: improper proof element 'guess' is like 'obtain', but derives
  2760 the obtained context from the course of reasoning!  For example:
  2761 
  2762   assume "EX x y. A x & B y"   -- "any previous fact"
  2763   then guess x and y by clarify
  2764 
  2765 This technique is potentially adventurous, depending on the facts and
  2766 proof tools being involved here.
  2767 
  2768 * Isar: known facts from the proof context may be specified as literal
  2769 propositions, using ASCII back-quote syntax.  This works wherever
  2770 named facts used to be allowed so far, in proof commands, proof
  2771 methods, attributes etc.  Literal facts are retrieved from the context
  2772 according to unification of type and term parameters.  For example,
  2773 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  2774 theorems in the current context, then these are valid literal facts:
  2775 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  2776 
  2777 There is also a proof method "fact" which does the same composition
  2778 for explicit goal states, e.g. the following proof texts coincide with
  2779 certain special cases of literal facts:
  2780 
  2781   have "A" by fact                 ==  note `A`
  2782   have "A ==> B" by fact           ==  note `A ==> B`
  2783   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  2784   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  2785 
  2786 * Isar: ":" (colon) is no longer a symbolic identifier character in
  2787 outer syntax.  Thus symbolic identifiers may be used without
  2788 additional white space in declarations like this: ``assume *: A''.
  2789 
  2790 * Isar: 'print_facts' prints all local facts of the current context,
  2791 both named and unnamed ones.
  2792 
  2793 * Isar: 'def' now admits simultaneous definitions, e.g.:
  2794 
  2795   def x == "t" and y == "u"
  2796 
  2797 * Isar: added command 'unfolding', which is structurally similar to
  2798 'using', but affects both the goal state and facts by unfolding given
  2799 rewrite rules.  Thus many occurrences of the 'unfold' method or
  2800 'unfolded' attribute may be replaced by first-class proof text.
  2801 
  2802 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  2803 and command 'unfolding' now all support object-level equalities
  2804 (potentially conditional).  The underlying notion of rewrite rule is
  2805 analogous to the 'rule_format' attribute, but *not* that of the
  2806 Simplifier (which is usually more generous).
  2807 
  2808 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  2809 premises of a theorem by n. Useful in conjunction with drule.
  2810 
  2811 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  2812 method expression within a sandbox consisting of the first N
  2813 sub-goals, which need to exist.  For example, ``simp_all [3]''
  2814 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  2815 simplifies all new goals that emerge from applying rule foo to the
  2816 originally first one.
  2817 
  2818 * Isar: schematic goals are no longer restricted to higher-order
  2819 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  2820 expected.
  2821 
  2822 * Isar: the conclusion of a long theorem statement is now either
  2823 'shows' (a simultaneous conjunction, as before), or 'obtains'
  2824 (essentially a disjunction of cases with local parameters and
  2825 assumptions).  The latter allows to express general elimination rules
  2826 adequately; in this notation common elimination rules look like this:
  2827 
  2828   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  2829     assumes "EX x. P x"
  2830     obtains x where "P x"
  2831 
  2832   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  2833     assumes "A & B"
  2834     obtains A and B
  2835 
  2836   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  2837     assumes "A | B"
  2838     obtains
  2839       A
  2840     | B
  2841 
  2842 The subsequent classical rules even refer to the formal "thesis"
  2843 explicitly:
  2844 
  2845   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  2846     obtains "~ thesis"
  2847 
  2848   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  2849     obtains "thesis ==> something"
  2850 
  2851 The actual proof of an 'obtains' statement is analogous to that of the
  2852 Isar proof element 'obtain', only that there may be several cases.
  2853 Optional case names may be specified in parentheses; these will be
  2854 available both in the present proof and as annotations in the
  2855 resulting rule, for later use with the 'cases' method (cf. attribute
  2856 case_names).
  2857 
  2858 * Isar: the assumptions of a long theorem statement are available as
  2859 "assms" fact in the proof context.  This is more appropriate than the
  2860 (historical) "prems", which refers to all assumptions of the current
  2861 context, including those from the target locale, proof body etc.
  2862 
  2863 * Isar: 'print_statement' prints theorems from the current theory or
  2864 proof context in long statement form, according to the syntax of a
  2865 top-level lemma.
  2866 
  2867 * Isar: 'obtain' takes an optional case name for the local context
  2868 introduction rule (default "that").
  2869 
  2870 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  2871 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  2872 to occur.
  2873 
  2874 * Pure: syntax "CONST name" produces a fully internalized constant
  2875 according to the current context.  This is particularly useful for
  2876 syntax translations that should refer to internal constant
  2877 representations independently of name spaces.
  2878 
  2879 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  2880 instead of "FOO ". This allows multiple binder declarations to coexist
  2881 in the same context.  INCOMPATIBILITY.
  2882 
  2883 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  2884 primitive that also works in a locale context (both for constants and
  2885 fixed variables). Type declaration and internal syntactic representation
  2886 of given constants retrieved from the context. Likewise, the
  2887 'no_notation' command allows to remove given syntax annotations from the
  2888 current context.
  2889 
  2890 * Isar/locales: new derived specification elements 'axiomatization',
  2891 'definition', 'abbreviation', which support type-inference, admit
  2892 object-level specifications (equality, equivalence).  See also the
  2893 isar-ref manual.  Examples:
  2894 
  2895   axiomatization
  2896     eq  (infix "===" 50) where
  2897     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  2898 
  2899   definition "f x y = x + y + 1"
  2900   definition g where "g x = f x x"
  2901 
  2902   abbreviation
  2903     neq  (infix "=!=" 50) where
  2904     "x =!= y == ~ (x === y)"
  2905 
  2906 These specifications may be also used in a locale context.  Then the
  2907 constants being introduced depend on certain fixed parameters, and the
  2908 constant name is qualified by the locale base name.  An internal
  2909 abbreviation takes care for convenient input and output, making the
  2910 parameters implicit and using the original short name.  See also
  2911 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  2912 entities from a monomorphic theory.
  2913 
  2914 Presently, abbreviations are only available 'in' a target locale, but
  2915 not inherited by general import expressions.  Also note that
  2916 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  2917 'translations' in common applications.  The "no_abbrevs" print mode
  2918 prevents folding of abbreviations in term output.
  2919 
  2920 Concrete syntax is attached to specified constants in internal form,
  2921 independently of name spaces.  The parse tree representation is
  2922 slightly different -- use 'notation' instead of raw 'syntax', and
  2923 'translations' with explicit "CONST" markup to accommodate this.
  2924 
  2925 * Pure/Isar: unified syntax for new-style specification mechanisms
  2926 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  2927 full type inference and dummy patterns ("_").  For example:
  2928 
  2929   definition "K x _ = x"
  2930 
  2931   inductive conj for A B
  2932   where "A ==> B ==> conj A B"
  2933 
  2934 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  2935 the current context.  Print mode "no_abbrevs" prevents inversion of
  2936 abbreviations on output.
  2937 
  2938 * Isar/locales: improved parameter handling: use of locales "var" and
  2939 "struct" no longer necessary; - parameter renamings are no longer
  2940 required to be injective.  For example, this allows to define
  2941 endomorphisms as locale endom = homom mult mult h.
  2942 
  2943 * Isar/locales: changed the way locales with predicates are defined.
  2944 Instead of accumulating the specification, the imported expression is
  2945 now an interpretation.  INCOMPATIBILITY: different normal form of
  2946 locale expressions.  In particular, in interpretations of locales with
  2947 predicates, goals repesenting already interpreted fragments are not
  2948 removed automatically.  Use methods `intro_locales' and
  2949 `unfold_locales'; see below.
  2950 
  2951 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  2952 provide backward reasoning on locales predicates.  The methods are
  2953 aware of interpretations and discharge corresponding goals.
  2954 `intro_locales' is less aggressive then `unfold_locales' and does not
  2955 unfold predicates to assumptions.
  2956 
  2957 * Isar/locales: the order in which locale fragments are accumulated
  2958 has changed.  This enables to override declarations from fragments due
  2959 to interpretations -- for example, unwanted simp rules.
  2960 
  2961 * Isar/locales: interpretation in theories and proof contexts has been
  2962 extended.  One may now specify (and prove) equations, which are
  2963 unfolded in interpreted theorems.  This is useful for replacing
  2964 defined concepts (constants depending on locale parameters) by
  2965 concepts already existing in the target context.  Example:
  2966 
  2967   interpretation partial_order ["op <= :: [int, int] => bool"]
  2968     where "partial_order.less (op <=) (x::int) y = (x < y)"
  2969 
  2970 Typically, the constant `partial_order.less' is created by a
  2971 definition specification element in the context of locale
  2972 partial_order.
  2973 
  2974 * Method "induct": improved internal context management to support
  2975 local fixes and defines on-the-fly. Thus explicit meta-level
  2976 connectives !!  and ==> are rarely required anymore in inductive goals
  2977 (using object-logic connectives for this purpose has been long
  2978 obsolete anyway). Common proof patterns are explained in
  2979 src/HOL/Induct/Common_Patterns.thy, see also
  2980 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  2981 examples.
  2982 
  2983 * Method "induct": improved handling of simultaneous goals. Instead of
  2984 introducing object-level conjunction, the statement is now split into
  2985 several conclusions, while the corresponding symbolic cases are nested
  2986 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  2987 see src/HOL/Induct/Common_Patterns.thy, for example.
  2988 
  2989 * Method "induct": mutual induction rules are now specified as a list
  2990 of rule sharing the same induction cases. HOL packages usually provide
  2991 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  2992 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  2993 mutual induction rules differently, i.e. like this:
  2994 
  2995   (induct rule: foo_bar.inducts)
  2996   (induct set: foo bar)
  2997   (induct pred: foo bar)
  2998   (induct type: foo bar)
  2999 
  3000 The ML function ProjectRule.projections turns old-style rules into the
  3001 new format.
  3002 
  3003 * Method "coinduct": dual of induction, see
  3004 src/HOL/Library/Coinductive_List.thy for various examples.
  3005 
  3006 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3007 considered a legacy feature.
  3008 
  3009 * Attribute "symmetric" produces result with standardized schematic
  3010 variables (index 0).  Potential INCOMPATIBILITY.
  3011 
  3012 * Simplifier: by default the simplifier trace only shows top level
  3013 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3014 default. Thus there is less danger of being flooded by the trace. The
  3015 trace indicates where parts have been suppressed.
  3016   
  3017 * Provers/classical: removed obsolete classical version of elim_format
  3018 attribute; classical elim/dest rules are now treated uniformly when
  3019 manipulating the claset.
  3020 
  3021 * Provers/classical: stricter checks to ensure that supplied intro,
  3022 dest and elim rules are well-formed; dest and elim rules must have at
  3023 least one premise.
  3024 
  3025 * Provers/classical: attributes dest/elim/intro take an optional
  3026 weight argument for the rule (just as the Pure versions).  Weights are
  3027 ignored by automated tools, but determine the search order of single
  3028 rule steps.
  3029 
  3030 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3031 where the body does not mention the bound variable.  Note that dummy
  3032 patterns implicitly depend on their context of bounds, which makes
  3033 "{_. _}" match any set comprehension as expected.  Potential
  3034 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3035 constant "_idtdummy" in the binding position.
  3036 
  3037 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3038 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3039 for example "A -> B" => "Pi A (%_. B)".
  3040 
  3041 * Pure: 'class_deps' command visualizes the subclass relation, using
  3042 the graph browser tool.
  3043 
  3044 * Pure: 'print_theory' now suppresses certain internal declarations by
  3045 default; use '!' option for full details.
  3046 
  3047 
  3048 *** HOL ***
  3049 
  3050 * Method "metis" proves goals by applying the Metis general-purpose
  3051 resolution prover (see also http://gilith.com/software/metis/).
  3052 Examples are in the directory MetisExamples.  WARNING: the
  3053 Isabelle/HOL-Metis integration does not yet work properly with
  3054 multi-threading.
  3055   
  3056 * Command 'sledgehammer' invokes external automatic theorem provers as
  3057 background processes.  It generates calls to the "metis" method if
  3058 successful. These can be pasted into the proof.  Users do not have to
  3059 wait for the automatic provers to return.  WARNING: does not really
  3060 work with multi-threading.
  3061 
  3062 * New "auto_quickcheck" feature tests outermost goal statements for
  3063 potential counter-examples.  Controlled by ML references
  3064 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3065 5000 milliseconds).  Fails silently if statements is outside of
  3066 executable fragment, or any other codgenerator problem occurs.
  3067 
  3068 * New constant "undefined" with axiom "undefined x = undefined".
  3069 
  3070 * Added class "HOL.eq", allowing for code generation with polymorphic
  3071 equality.
  3072 
  3073 * Some renaming of class constants due to canonical name prefixing in
  3074 the new 'class' package:
  3075 
  3076     HOL.abs ~> HOL.abs_class.abs
  3077     HOL.divide ~> HOL.divide_class.divide
  3078     0 ~> HOL.zero_class.zero
  3079     1 ~> HOL.one_class.one
  3080     op + ~> HOL.plus_class.plus
  3081     op - ~> HOL.minus_class.minus
  3082     uminus ~> HOL.minus_class.uminus
  3083     op * ~> HOL.times_class.times
  3084     op < ~> HOL.ord_class.less
  3085     op <= > HOL.ord_class.less_eq
  3086     Nat.power ~> Power.power_class.power
  3087     Nat.size ~> Nat.size_class.size
  3088     Numeral.number_of ~> Numeral.number_class.number_of
  3089     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3090     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3091     Orderings.min ~> Orderings.ord_class.min
  3092     Orderings.max ~> Orderings.ord_class.max
  3093     Divides.op div ~> Divides.div_class.div
  3094     Divides.op mod ~> Divides.div_class.mod
  3095     Divides.op dvd ~> Divides.div_class.dvd
  3096 
  3097 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3098 
  3099 a) User-defined constants using any of the names "plus", "minus",
  3100 "times", "less" or "less_eq". The standard syntax translations for
  3101 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3102 names.
  3103 
  3104 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3105 INCOMPATIBILITY: use more specific names.
  3106 
  3107 c) Permutative equations (e.g. "a + b = b + a")
  3108 Since the change of names also changes the order of terms, permutative
  3109 rewrite rules may get applied in a different order. Experience shows
  3110 that this is rarely the case (only two adaptions in the whole Isabelle
  3111 distribution).  INCOMPATIBILITY: rewrite proofs
  3112 
  3113 d) ML code directly refering to constant names
  3114 This in general only affects hand-written proof tactics, simprocs and
  3115 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3116 Consider using @{const_name} antiquotation.
  3117 
  3118 * New class "default" with associated constant "default".
  3119 
  3120 * Function "sgn" is now overloaded and available on int, real, complex
  3121 (and other numeric types), using class "sgn".  Two possible defs of
  3122 sgn are given as equational assumptions in the classes sgn_if and
  3123 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3124 INCOMPATIBILITY.
  3125 
  3126 * Locale "partial_order" now unified with class "order" (cf. theory
  3127 Orderings), added parameter "less".  INCOMPATIBILITY.
  3128 
  3129 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3130 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3131 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3132 
  3133 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3134 changed order of proof goals in instance proofs.
  3135 
  3136 * The transitivity reasoner for partial and linear orders is set up
  3137 for classes "order" and "linorder".  Instances of the reasoner are available
  3138 in all contexts importing or interpreting the corresponding locales.
  3139 Method "order" invokes the reasoner separately; the reasoner
  3140 is also integrated with the Simplifier as a solver.  Diagnostic
  3141 command 'print_orders' shows the available instances of the reasoner
  3142 in the current context.
  3143 
  3144 * Localized monotonicity predicate in theory "Orderings"; integrated
  3145 lemmas max_of_mono and min_of_mono with this predicate.
  3146 INCOMPATIBILITY.
  3147 
  3148 * Formulation of theorem "dense" changed slightly due to integration
  3149 with new class dense_linear_order.
  3150 
  3151 * Uniform lattice theory development in HOL.
  3152 
  3153     constants "meet" and "join" now named "inf" and "sup"
  3154     constant "Meet" now named "Inf"
  3155 
  3156     classes "meet_semilorder" and "join_semilorder" now named
  3157       "lower_semilattice" and "upper_semilattice"
  3158     class "lorder" now named "lattice"
  3159     class "comp_lat" now named "complete_lattice"
  3160 
  3161     Instantiation of lattice classes allows explicit definitions
  3162     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3163 
  3164   INCOMPATIBILITY.  Theorem renames:
  3165 
  3166     meet_left_le            ~> inf_le1
  3167     meet_right_le           ~> inf_le2
  3168     join_left_le            ~> sup_ge1
  3169     join_right_le           ~> sup_ge2
  3170     meet_join_le            ~> inf_sup_ord
  3171     le_meetI                ~> le_infI
  3172     join_leI                ~> le_supI
  3173     le_meet                 ~> le_inf_iff
  3174     le_join                 ~> ge_sup_conv
  3175     meet_idempotent         ~> inf_idem
  3176     join_idempotent         ~> sup_idem
  3177     meet_comm               ~> inf_commute
  3178     join_comm               ~> sup_commute
  3179     meet_leI1               ~> le_infI1
  3180     meet_leI2               ~> le_infI2
  3181     le_joinI1               ~> le_supI1
  3182     le_joinI2               ~> le_supI2
  3183     meet_assoc              ~> inf_assoc
  3184     join_assoc              ~> sup_assoc
  3185     meet_left_comm          ~> inf_left_commute
  3186     meet_left_idempotent    ~> inf_left_idem
  3187     join_left_comm          ~> sup_left_commute
  3188     join_left_idempotent    ~> sup_left_idem
  3189     meet_aci                ~> inf_aci
  3190     join_aci                ~> sup_aci
  3191     le_def_meet             ~> le_iff_inf
  3192     le_def_join             ~> le_iff_sup
  3193     join_absorp2            ~> sup_absorb2
  3194     join_absorp1            ~> sup_absorb1
  3195     meet_absorp1            ~> inf_absorb1
  3196     meet_absorp2            ~> inf_absorb2
  3197     meet_join_absorp        ~> inf_sup_absorb
  3198     join_meet_absorp        ~> sup_inf_absorb
  3199     distrib_join_le         ~> distrib_sup_le
  3200     distrib_meet_le         ~> distrib_inf_le
  3201 
  3202     add_meet_distrib_left   ~> add_inf_distrib_left
  3203     add_join_distrib_left   ~> add_sup_distrib_left
  3204     is_join_neg_meet        ~> is_join_neg_inf
  3205     is_meet_neg_join        ~> is_meet_neg_sup
  3206     add_meet_distrib_right  ~> add_inf_distrib_right
  3207     add_join_distrib_right  ~> add_sup_distrib_right
  3208     add_meet_join_distribs  ~> add_sup_inf_distribs
  3209     join_eq_neg_meet        ~> sup_eq_neg_inf
  3210     meet_eq_neg_join        ~> inf_eq_neg_sup
  3211     add_eq_meet_join        ~> add_eq_inf_sup
  3212     meet_0_imp_0            ~> inf_0_imp_0
  3213     join_0_imp_0            ~> sup_0_imp_0
  3214     meet_0_eq_0             ~> inf_0_eq_0
  3215     join_0_eq_0             ~> sup_0_eq_0
  3216     neg_meet_eq_join        ~> neg_inf_eq_sup
  3217     neg_join_eq_meet        ~> neg_sup_eq_inf
  3218     join_eq_if              ~> sup_eq_if
  3219 
  3220     mono_meet               ~> mono_inf
  3221     mono_join               ~> mono_sup
  3222     meet_bool_eq            ~> inf_bool_eq
  3223     join_bool_eq            ~> sup_bool_eq
  3224     meet_fun_eq             ~> inf_fun_eq
  3225     join_fun_eq             ~> sup_fun_eq
  3226     meet_set_eq             ~> inf_set_eq
  3227     join_set_eq             ~> sup_set_eq
  3228     meet1_iff               ~> inf1_iff
  3229     meet2_iff               ~> inf2_iff
  3230     meet1I                  ~> inf1I
  3231     meet2I                  ~> inf2I
  3232     meet1D1                 ~> inf1D1
  3233     meet2D1                 ~> inf2D1
  3234     meet1D2                 ~> inf1D2
  3235     meet2D2                 ~> inf2D2
  3236     meet1E                  ~> inf1E
  3237     meet2E                  ~> inf2E
  3238     join1_iff               ~> sup1_iff
  3239     join2_iff               ~> sup2_iff
  3240     join1I1                 ~> sup1I1
  3241     join2I1                 ~> sup2I1
  3242     join1I1                 ~> sup1I1
  3243     join2I2                 ~> sup1I2
  3244     join1CI                 ~> sup1CI
  3245     join2CI                 ~> sup2CI
  3246     join1E                  ~> sup1E
  3247     join2E                  ~> sup2E
  3248 
  3249     is_meet_Meet            ~> is_meet_Inf
  3250     Meet_bool_def           ~> Inf_bool_def
  3251     Meet_fun_def            ~> Inf_fun_def
  3252     Meet_greatest           ~> Inf_greatest
  3253     Meet_lower              ~> Inf_lower
  3254     Meet_set_def            ~> Inf_set_def
  3255 
  3256     Sup_def                 ~> Sup_Inf
  3257     Sup_bool_eq             ~> Sup_bool_def
  3258     Sup_fun_eq              ~> Sup_fun_def
  3259     Sup_set_eq              ~> Sup_set_def
  3260 
  3261     listsp_meetI            ~> listsp_infI
  3262     listsp_meet_eq          ~> listsp_inf_eq
  3263 
  3264     meet_min                ~> inf_min
  3265     join_max                ~> sup_max
  3266 
  3267 * Added syntactic class "size"; overloaded constant "size" now has
  3268 type "'a::size ==> bool"
  3269 
  3270 * Internal reorganisation of `size' of datatypes: size theorems
  3271 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3272 simplification rules by default!); theorems "prod.size" now named
  3273 "*.size".
  3274 
  3275 * Class "div" now inherits from class "times" rather than "type".
  3276 INCOMPATIBILITY.
  3277 
  3278 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  3279 Linorder etc.  have disappeared; operations defined in terms of
  3280 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  3281 
  3282 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  3283 
  3284 * HOL-Word: New extensive library and type for generic, fixed size
  3285 machine words, with arithemtic, bit-wise, shifting and rotating
  3286 operations, reflection into int, nat, and bool lists, automation for
  3287 linear arithmetic (by automatic reflection into nat or int), including
  3288 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  3289 arithmetic type classes, supporting automatic simplification of
  3290 numerals on all operations.
  3291 
  3292 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  3293 
  3294 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  3295 
  3296 * Code generator library theories:
  3297   - Code_Integer represents HOL integers by big integer literals in target
  3298     languages.
  3299   - Code_Char represents HOL characters by character literals in target
  3300     languages.
  3301   - Code_Char_chr like Code_Char, but also offers treatment of character
  3302     codes; includes Code_Integer.
  3303   - Executable_Set allows to generate code for finite sets using lists.
  3304   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  3305     denominator).
  3306   - Executable_Real implements a subset of real numbers, namly those
  3307     representable by rational numbers.
  3308   - Efficient_Nat implements natural numbers by integers, which in general will
  3309     result in higher efficency; pattern matching with 0/Suc is eliminated;
  3310     includes Code_Integer.
  3311   - Code_Index provides an additional datatype index which is mapped to
  3312     target-language built-in integers.
  3313   - Code_Message provides an additional datatype message_string which is isomorphic to
  3314     strings; messages are mapped to target-language strings.
  3315 
  3316 * New package for inductive predicates
  3317 
  3318   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  3319 
  3320     inductive
  3321       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3322       for z_1 :: U_1 and ... and z_n :: U_m
  3323     where
  3324       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3325     | ...
  3326 
  3327   with full support for type-inference, rather than
  3328 
  3329     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3330 
  3331     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3332     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3333 
  3334     inductive "s z_1 ... z_m"
  3335     intros
  3336       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3337       ...
  3338 
  3339   For backward compatibility, there is a wrapper allowing inductive
  3340   sets to be defined with the new package via
  3341 
  3342     inductive_set
  3343       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3344       for z_1 :: U_1 and ... and z_n :: U_m
  3345     where
  3346       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3347     | ...
  3348 
  3349   or
  3350 
  3351     inductive_set
  3352       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3353       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3354       for z_1 :: U_1 and ... and z_n :: U_m
  3355     where
  3356       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3357     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3358     | ...
  3359 
  3360   if the additional syntax "p ..." is required.
  3361 
  3362   Numerous examples can be found in the subdirectories src/HOL/Auth,
  3363   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  3364 
  3365   INCOMPATIBILITIES:
  3366 
  3367   - Since declaration and definition of inductive sets or predicates
  3368     is no longer separated, abbreviations involving the newly
  3369     introduced sets or predicates must be specified together with the
  3370     introduction rules after the 'where' keyword (see above), rather
  3371     than before the actual inductive definition.
  3372 
  3373   - The variables in induction and elimination rules are now
  3374     quantified in the order of their occurrence in the introduction
  3375     rules, rather than in alphabetical order. Since this may break
  3376     some proofs, these proofs either have to be repaired, e.g. by
  3377     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  3378     statements of the form
  3379 
  3380       case (rule_i a_i_1 ... a_i_{k_i})
  3381 
  3382     or the old order of quantification has to be restored by explicitly adding
  3383     meta-level quantifiers in the introduction rules, i.e.
  3384 
  3385       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  3386 
  3387   - The format of the elimination rules is now
  3388 
  3389       p z_1 ... z_m x_1 ... x_n ==>
  3390         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3391         ==> ... ==> P
  3392 
  3393     for predicates and
  3394 
  3395       (x_1, ..., x_n) : s z_1 ... z_m ==>
  3396         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3397         ==> ... ==> P
  3398 
  3399     for sets rather than
  3400 
  3401       x : s z_1 ... z_m ==>
  3402         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  3403         ==> ... ==> P
  3404 
  3405     This may require terms in goals to be expanded to n-tuples
  3406     (e.g. using case_tac or simplification with the split_paired_all
  3407     rule) before the above elimination rule is applicable.
  3408 
  3409   - The elimination or case analysis rules for (mutually) inductive
  3410     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  3411     list of rules "p_1_..._p_k.elims" is no longer available.
  3412 
  3413 * New package "function"/"fun" for general recursive functions,
  3414 supporting mutual and nested recursion, definitions in local contexts,
  3415 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  3416 for small examples, and the separate tutorial on the function
  3417 package. The old recdef "package" is still available as before, but
  3418 users are encouraged to use the new package.
  3419 
  3420 * Method "lexicographic_order" automatically synthesizes termination
  3421 relations as lexicographic combinations of size measures. 
  3422 
  3423 * Case-expressions allow arbitrary constructor-patterns (including
  3424 "_") and take their order into account, like in functional
  3425 programming.  Internally, this is translated into nested
  3426 case-expressions; missing cases are added and mapped to the predefined
  3427 constant "undefined". In complicated cases printing may no longer show
  3428 the original input but the internal form. Lambda-abstractions allow
  3429 the same form of pattern matching: "% pat1 => e1 | ..." is an
  3430 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  3431 variable.
  3432 
  3433 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  3434 is an abbreviation for "of_nat :: nat => int". The simplification
  3435 rules for "of_nat" have been changed to work like "int" did
  3436 previously.  Potential INCOMPATIBILITY:
  3437   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  3438   - of_nat_diff and of_nat_mult are no longer default simp rules
  3439 
  3440 * Method "algebra" solves polynomial equations over (semi)rings using
  3441 Groebner bases. The (semi)ring structure is defined by locales and the
  3442 tool setup depends on that generic context. Installing the method for
  3443 a specific type involves instantiating the locale and possibly adding
  3444 declarations for computation on the coefficients.  The method is
  3445 already instantiated for natural numbers and for the axiomatic class
  3446 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  3447 CALCULEMUS 2007 for the general principles underlying this
  3448 architecture of context-aware proof-tools.
  3449 
  3450 * Method "ferrack" implements quantifier elimination over
  3451 special-purpose dense linear orders using locales (analogous to
  3452 "algebra"). The method is already installed for class
  3453 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  3454 rat, etc.
  3455 
  3456 * Former constant "List.op @" now named "List.append".  Use ML
  3457 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  3458 circumvent possible incompatibilities when working on ML level.
  3459 
  3460 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  3461 
  3462 * New function listsum :: 'a list => 'a for arbitrary monoids.
  3463 Special syntax: "SUM x <- xs. f x" (and latex variants)
  3464 
  3465 * New syntax for Haskell-like list comprehension (input only), eg.
  3466 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  3467 
  3468 * The special syntax for function "filter" has changed from [x :
  3469 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  3470 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  3471 
  3472 * [a..b] is now defined for arbitrary linear orders.  It used to be
  3473 defined on nat only, as an abbreviation for [a..<Suc b]
  3474 INCOMPATIBILITY.
  3475 
  3476 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  3477 
  3478 * New functions "sorted" and "sort" in src/HOL/List.thy.
  3479 
  3480 * New lemma collection field_simps (an extension of ring_simps) for
  3481 manipulating (in)equations involving division. Multiplies with all
  3482 denominators that can be proved to be non-zero (in equations) or
  3483 positive/negative (in inequations).
  3484 
  3485 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  3486 have been improved and renamed to ring_simps, group_simps and
  3487 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  3488 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  3489 
  3490 * Theory Library/Commutative_Ring: switched from recdef to function
  3491 package; constants add, mul, pow now curried.  Infix syntax for
  3492 algebraic operations.
  3493 
  3494 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  3495 INCOMPATIBILITY.
  3496 
  3497 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  3498 INCOMPATIBILITY.
  3499 
  3500 * HOL/records: generalised field-update to take a function on the
  3501 field rather than the new value: r(|A := x|) is translated to A_update
  3502 (K x) r The K-combinator that is internally used is called K_record.
  3503 INCOMPATIBILITY: Usage of the plain update functions has to be
  3504 adapted.
  3505  
  3506 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  3507 * x = 0, which are required for a semiring.  Richer structures do not
  3508 inherit from semiring_0 anymore, because this property is a theorem
  3509 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  3510 there is more to prove, but this is mostly trivial.
  3511 
  3512 * Class "recpower" is generalized to arbitrary monoids, not just
  3513 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  3514 commutativity or semiring properties additionally.
  3515 
  3516 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  3517 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  3518 better use 'abbreviation'.
  3519 
  3520 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  3521 
  3522 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  3523 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  3524 significant changes for setting up numeral syntax for types:
  3525   - New constants Numeral.pred and Numeral.succ instead
  3526       of former Numeral.bin_pred and Numeral.bin_succ.
  3527   - Use integer operations instead of bin_add, bin_mult and so on.
  3528   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  3529   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  3530 
  3531 See src/HOL/Integ/IntArith.thy for an example setup.
  3532 
  3533 * Command 'normal_form' computes the normal form of a term that may
  3534 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  3535 produces ``[b, c, a]'' (without proof).  This command is suitable for
  3536 heavy-duty computations because the functions are compiled to ML
  3537 first.  Correspondingly, a method "normalization" is provided.  See
  3538 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  3539 
  3540 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  3541 25 like -->); output depends on the "iff" print_mode, the default is
  3542 "A = B" (with priority 50).
  3543 
  3544 * Relations less (<) and less_eq (<=) are also available on type bool.
  3545 Modified syntax to disallow nesting without explicit parentheses,
  3546 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  3547 INCOMPATIBILITY.
  3548 
  3549 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  3550 
  3551 * Relation composition operator "op O" now has precedence 75 and binds
  3552 stronger than union and intersection. INCOMPATIBILITY.
  3553 
  3554 * The old set interval syntax "{m..n(}" (and relatives) has been
  3555 removed.  Use "{m..<n}" (and relatives) instead.
  3556 
  3557 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  3558 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  3559 ``declare [[simproc del: neq]]''.
  3560 
  3561 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  3562 True/False.
  3563 
  3564 * Theorem Cons_eq_map_conv no longer declared as "simp".
  3565 
  3566 * Theorem setsum_mult renamed to setsum_right_distrib.
  3567 
  3568 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  3569 ``rule'' method.
  3570 
  3571 * Reimplemented methods "sat" and "satx", with several improvements:
  3572 goals no longer need to be stated as "<prems> ==> False", equivalences
  3573 (i.e. "=" on type bool) are handled, variable names of the form
  3574 "lit_<n>" are no longer reserved, significant speedup.
  3575 
  3576 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  3577 zChaff is still supported as well.
  3578 
  3579 * 'inductive' and 'datatype': provide projections of mutual rules,
  3580 bundled as foo_bar.inducts;
  3581 
  3582 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  3583 Library.
  3584 
  3585 * Library: moved theory Accessible_Part to main HOL.
  3586 
  3587 * Library: added theory Coinductive_List of potentially infinite lists
  3588 as greatest fixed-point.
  3589 
  3590 * Library: added theory AssocList which implements (finite) maps as
  3591 association lists.
  3592 
  3593 * Method "evaluation" solves goals (i.e. a boolean expression)
  3594 efficiently by compiling it to ML.  The goal is "proved" (via an
  3595 oracle) if it evaluates to True.
  3596 
  3597 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  3598 also when invoked by the simplifier.  This results in the Simplifier
  3599 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  3600 Configuration option fast_arith_split_limit=0 recovers the old
  3601 behavior.
  3602 
  3603 * Support for hex (0x20) and binary (0b1001) numerals.
  3604 
  3605 * New method: reify eqs (t), where eqs are equations for an
  3606 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  3607 parameter, computes a term s::'b and a list xs::'a list and proves the
  3608 theorem I xs s = t. This is also known as reification or quoting. The
  3609 resulting theorem is applied to the subgoal to substitute t with I xs
  3610 s.  If t is omitted, the subgoal itself is reified.
  3611 
  3612 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  3613 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  3614 where f is supposed to be a computable function (in the sense of code
  3615 generattion). The method uses reify to compute s and xs as above then
  3616 applies corr_thm and uses normalization by evaluation to "prove" f s =
  3617 r and finally gets the theorem t = r, which is again applied to the
  3618 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  3619 
  3620 * Reflection: Automatic reification now handels binding, an example is
  3621 available in src/HOL/ex/ReflectionEx.thy
  3622 
  3623 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  3624 command 'statespace' that is similar to 'record', but introduces an
  3625 abstract specification based on the locale infrastructure instead of
  3626 HOL types.  This leads to extra flexibility in composing state spaces,
  3627 in particular multiple inheritance and renaming of components.
  3628 
  3629 
  3630 *** HOL-Complex ***
  3631 
  3632 * Hyperreal: Functions root and sqrt are now defined on negative real
  3633 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  3634 Nonnegativity side conditions have been removed from many lemmas, so
  3635 that more subgoals may now be solved by simplification; potential
  3636 INCOMPATIBILITY.
  3637 
  3638 * Real: new type classes formalize real normed vector spaces and
  3639 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  3640 and norm :: 'a => real.
  3641 
  3642 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  3643 reals into other types. The overloaded constant Reals :: 'a set is now
  3644 defined as range of_real; potential INCOMPATIBILITY.
  3645 
  3646 * Real: proper support for ML code generation, including 'quickcheck'.
  3647 Reals are implemented as arbitrary precision rationals.
  3648 
  3649 * Hyperreal: Several constants that previously worked only for the
  3650 reals have been generalized, so they now work over arbitrary vector
  3651 spaces. Type annotations may need to be added in some cases; potential
  3652 INCOMPATIBILITY.
  3653 
  3654   Infinitesimal  :: ('a::real_normed_vector) star set
  3655   HFinite        :: ('a::real_normed_vector) star set
  3656   HInfinite      :: ('a::real_normed_vector) star set
  3657   approx         :: ('a::real_normed_vector) star => 'a star => bool
  3658   monad          :: ('a::real_normed_vector) star => 'a star set
  3659   galaxy         :: ('a::real_normed_vector) star => 'a star set
  3660   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  3661   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  3662   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  3663   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  3664   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  3665   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  3666   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  3667   sgn            :: 'a::real_normed_vector => 'a
  3668   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  3669 
  3670 * Complex: Some complex-specific constants are now abbreviations for
  3671 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  3672 hnorm.  Other constants have been entirely removed in favor of the
  3673 polymorphic versions (INCOMPATIBILITY):
  3674 
  3675   approx        <-- capprox
  3676   HFinite       <-- CFinite
  3677   HInfinite     <-- CInfinite
  3678   Infinitesimal <-- CInfinitesimal
  3679   monad         <-- cmonad
  3680   galaxy        <-- cgalaxy
  3681   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  3682   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  3683   (ns)deriv     <-- (ns)cderiv
  3684 
  3685 
  3686 *** HOL-Algebra ***
  3687 
  3688 * Formalisation of ideals and the quotient construction over rings.
  3689 
  3690 * Order and lattice theory no longer based on records.
  3691 INCOMPATIBILITY.
  3692 
  3693 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  3694 greatest_closed.  INCOMPATIBILITY.
  3695 
  3696 * Method algebra is now set up via an attribute.  For examples see
  3697 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  3698 of algebraic structures.
  3699 
  3700 * Renamed theory CRing to Ring.
  3701 
  3702 
  3703 *** HOL-Nominal ***
  3704 
  3705 * Substantial, yet incomplete support for nominal datatypes (binding
  3706 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  3707 src/HOL/Nominal/Examples.  Prospective users should consult
  3708 http://isabelle.in.tum.de/nominal/
  3709 
  3710 
  3711 *** ML ***
  3712 
  3713 * ML basics: just one true type int, which coincides with IntInf.int
  3714 (even on SML/NJ).
  3715 
  3716 * ML within Isar: antiquotations allow to embed statically-checked
  3717 formal entities in the source, referring to the context available at
  3718 compile-time.  For example:
  3719 
  3720 ML {* @{sort "{zero,one}"} *}
  3721 ML {* @{typ "'a => 'b"} *}
  3722 ML {* @{term "%x. x"} *}
  3723 ML {* @{prop "x == y"} *}
  3724 ML {* @{ctyp "'a => 'b"} *}
  3725 ML {* @{cterm "%x. x"} *}
  3726 ML {* @{cprop "x == y"} *}
  3727 ML {* @{thm asm_rl} *}
  3728 ML {* @{thms asm_rl} *}
  3729 ML {* @{type_name c} *}
  3730 ML {* @{type_syntax c} *}
  3731 ML {* @{const_name c} *}
  3732 ML {* @{const_syntax c} *}
  3733 ML {* @{context} *}
  3734 ML {* @{theory} *}
  3735 ML {* @{theory Pure} *}
  3736 ML {* @{theory_ref} *}
  3737 ML {* @{theory_ref Pure} *}
  3738 ML {* @{simpset} *}
  3739 ML {* @{claset} *}
  3740 ML {* @{clasimpset} *}
  3741 
  3742 The same works for sources being ``used'' within an Isar context.
  3743 
  3744 * ML in Isar: improved error reporting; extra verbosity with
  3745 ML_Context.trace enabled.
  3746 
  3747 * Pure/General/table.ML: the join operations now works via exceptions
  3748 DUP/SAME instead of type option. This is simpler in simple cases, and
  3749 admits slightly more efficient complex applications.
  3750 
  3751 * Pure: 'advanced' translation functions (parse_translation etc.) now
  3752 use Context.generic instead of just theory.
  3753 
  3754 * Pure: datatype Context.generic joins theory/Proof.context and
  3755 provides some facilities for code that works in either kind of
  3756 context, notably GenericDataFun for uniform theory and proof data.
  3757 
  3758 * Pure: simplified internal attribute type, which is now always
  3759 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  3760 local (Proof.context) attributes have been discontinued, while
  3761 minimizing code duplication. Thm.rule_attribute and
  3762 Thm.declaration_attribute build canonical attributes; see also structure
  3763 Context for further operations on Context.generic, notably
  3764 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  3765 declarations and definitions.
  3766 
  3767 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  3768 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  3769 init only required for impure data. INCOMPATIBILITY: empty really need
  3770 to be empty (no dependencies on theory content!)
  3771 
  3772 * Pure/kernel: consts certification ignores sort constraints given in
  3773 signature declarations. (This information is not relevant to the
  3774 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  3775 potential INCOMPATIBILITY.
  3776 
  3777 * Pure: axiomatic type classes are now purely definitional, with
  3778 explicit proofs of class axioms and super class relations performed
  3779 internally. See Pure/axclass.ML for the main internal interfaces --
  3780 notably AxClass.define_class supercedes AxClass.add_axclass, and
  3781 AxClass.axiomatize_class/classrel/arity supersede
  3782 Sign.add_classes/classrel/arities.
  3783 
  3784 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  3785 global/local versions on theory vs. Proof.context have been
  3786 discontinued; Attrib.syntax and Method.syntax have been adapted
  3787 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  3788 attributes, methods, etc.
  3789 
  3790 * Pure: several functions of signature "... -> theory -> theory * ..."
  3791 have been reoriented to "... -> theory -> ... * theory" in order to
  3792 allow natural usage in combination with the ||>, ||>>, |-> and
  3793 fold_map combinators.
  3794 
  3795 * Pure: official theorem names (closed derivations) and additional
  3796 comments (tags) are now strictly separate.  Name hints -- which are
  3797 maintained as tags -- may be attached any time without affecting the
  3798 derivation.
  3799 
  3800 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  3801 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  3802 achieve the old behaviour.
  3803 
  3804 * Pure: the "Goal" constant is now called "prop", supporting a
  3805 slightly more general idea of ``protecting'' meta-level rule
  3806 statements.
  3807 
  3808 * Pure: Logic.(un)varify only works in a global context, which is now
  3809 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  3810 Logic.legacy_(un)varify as temporary workaround.
  3811 
  3812 * Pure: structure Name provides scalable operations for generating
  3813 internal variable names, notably Name.variants etc.  This replaces
  3814 some popular functions from term.ML:
  3815 
  3816   Term.variant		->  Name.variant
  3817   Term.variantlist	->  Name.variant_list
  3818   Term.invent_names	->  Name.invent_list
  3819 
  3820 Note that low-level renaming rarely occurs in new code -- operations
  3821 from structure Variable are used instead (see below).
  3822 
  3823 * Pure: structure Variable provides fundamental operations for proper
  3824 treatment of fixed/schematic variables in a context.  For example,
  3825 Variable.import introduces fixes for schematics of given facts and
  3826 Variable.export reverses the effect (up to renaming) -- this replaces
  3827 various freeze_thaw operations.
  3828 
  3829 * Pure: structure Goal provides simple interfaces for
  3830 init/conclude/finish and tactical prove operations (replacing former
  3831 Tactic.prove).  Goal.prove is the canonical way to prove results
  3832 within a given context; Goal.prove_global is a degraded version for
  3833 theory level goals, including a global Drule.standard.  Note that
  3834 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  3835 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  3836 in a locale context).
  3837 
  3838 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  3839 and type checking (Syntax.check_term etc.), with common combinations
  3840 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  3841 which are considered legacy and await removal.
  3842 
  3843 * Pure/Syntax: generic interfaces for type unchecking
  3844 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  3845 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  3846 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  3847 available for convenience, but refer to the very same operations using
  3848 a mere theory instead of a full context.
  3849 
  3850 * Isar: simplified treatment of user-level errors, using exception
  3851 ERROR of string uniformly.  Function error now merely raises ERROR,
  3852 without any side effect on output channels.  The Isar toplevel takes
  3853 care of proper display of ERROR exceptions.  ML code may use plain
  3854 handle/can/try; cat_error may be used to concatenate errors like this:
  3855 
  3856   ... handle ERROR msg => cat_error msg "..."
  3857 
  3858 Toplevel ML code (run directly or through the Isar toplevel) may be
  3859 embedded into the Isar toplevel with exception display/debug like
  3860 this:
  3861 
  3862   Isar.toplevel (fn () => ...)
  3863 
  3864 INCOMPATIBILITY, removed special transform_error facilities, removed
  3865 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  3866 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  3867 -- use plain ERROR instead.
  3868 
  3869 * Isar: theory setup now has type (theory -> theory), instead of a
  3870 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  3871 
  3872 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  3873 ProofContext.debug/verbose flags.
  3874 
  3875 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  3876 theory before entering a proof state.  Transactions now always see a
  3877 quasi-functional intermediate checkpoint, both in interactive and
  3878 batch mode.
  3879 
  3880 * Isar: simplified interfaces for outer syntax.  Renamed
  3881 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  3882 OuterSyntax.add_parsers -- this functionality is now included in
  3883 OuterSyntax.command etc.  INCOMPATIBILITY.
  3884 
  3885 * Simplifier: the simpset of a running simplification process now
  3886 contains a proof context (cf. Simplifier.the_context), which is the
  3887 very context that the initial simpset has been retrieved from (by
  3888 simpset_of/local_simpset_of).  Consequently, all plug-in components
  3889 (solver, looper etc.) may depend on arbitrary proof data.
  3890 
  3891 * Simplifier.inherit_context inherits the proof context (plus the
  3892 local bounds) of the current simplification process; any simproc
  3893 etc. that calls the Simplifier recursively should do this!  Removed
  3894 former Simplifier.inherit_bounds, which is already included here --
  3895 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  3896 specify an explicit context using Simplifier.context/theory_context.
  3897 
  3898 * Simplifier/Classical Reasoner: more abstract interfaces
  3899 change_simpset/claset for modifying the simpset/claset reference of a
  3900 theory; raw versions simpset/claset_ref etc. have been discontinued --
  3901 INCOMPATIBILITY.
  3902 
  3903 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  3904 "Trueprop" etc.
  3905 
  3906 
  3907 *** System ***
  3908 
  3909 * settings: the default heap location within ISABELLE_HOME_USER now
  3910 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  3911 Isabelle installations.
  3912 
  3913 * isabelle-process: option -S (secure mode) disables some critical
  3914 operations, notably runtime compilation and evaluation of ML source
  3915 code.
  3916 
  3917 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  3918 
  3919 * Support for parallel execution, using native multicore support of
  3920 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  3921 independent theories, according to the given theory header
  3922 specifications. The maximum number of worker threads is specified via
  3923 usedir option -M or the "max-threads" setting in Proof General. A
  3924 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  3925 to 6 on a 8-core machine.  User-code needs to observe certain
  3926 guidelines for thread-safe programming, see appendix A in the Isar
  3927 Implementation manual.
  3928 
  3929 
  3930 
  3931 New in Isabelle2005 (October 2005)
  3932 ----------------------------------
  3933 
  3934 *** General ***
  3935 
  3936 * Theory headers: the new header syntax for Isar theories is
  3937 
  3938   theory <name>
  3939   imports <theory1> ... <theoryN>
  3940   uses <file1> ... <fileM>
  3941   begin
  3942 
  3943 where the 'uses' part is optional.  The previous syntax
  3944 
  3945   theory <name> = <theory1> + ... + <theoryN>:
  3946 
  3947 will disappear in the next release.  Use isatool fixheaders to convert
  3948 existing theory files.  Note that there is no change in ancient
  3949 non-Isar theories now, but these will disappear soon.
  3950 
  3951 * Theory loader: parent theories can now also be referred to via
  3952 relative and absolute paths.
  3953 
  3954 * Command 'find_theorems' searches for a list of criteria instead of a
  3955 list of constants. Known criteria are: intro, elim, dest, name:string,
  3956 simp:term, and any term. Criteria can be preceded by '-' to select
  3957 theorems that do not match. Intro, elim, dest select theorems that
  3958 match the current goal, name:s selects theorems whose fully qualified
  3959 name contain s, and simp:term selects all simplification rules whose
  3960 lhs match term.  Any other term is interpreted as pattern and selects
  3961 all theorems matching the pattern. Available in ProofGeneral under
  3962 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  3963 
  3964   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  3965 
  3966 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  3967 matching the current goal as introduction rule and not having "HOL."
  3968 in their name (i.e. not being defined in theory HOL).
  3969 
  3970 * Command 'thms_containing' has been discontinued in favour of
  3971 'find_theorems'; INCOMPATIBILITY.
  3972 
  3973 * Communication with Proof General is now 8bit clean, which means that
  3974 Unicode text in UTF-8 encoding may be used within theory texts (both
  3975 formal and informal parts).  Cf. option -U of the Isabelle Proof
  3976 General interface.  Here are some simple examples (cf. src/HOL/ex):
  3977 
  3978   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  3979   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  3980 
  3981 * Improved efficiency of the Simplifier and, to a lesser degree, the
  3982 Classical Reasoner.  Typical big applications run around 2 times
  3983 faster.
  3984 
  3985 
  3986 *** Document preparation ***
  3987 
  3988 * Commands 'display_drafts' and 'print_drafts' perform simple output
  3989 of raw sources.  Only those symbols that do not require additional
  3990 LaTeX packages (depending on comments in isabellesym.sty) are
  3991 displayed properly, everything else is left verbatim.  isatool display
  3992 and isatool print are used as front ends (these are subject to the
  3993 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  3994 
  3995 * Command tags control specific markup of certain regions of text,
  3996 notably folding and hiding.  Predefined tags include "theory" (for
  3997 theory begin and end), "proof" for proof commands, and "ML" for
  3998 commands involving ML code; the additional tags "visible" and
  3999 "invisible" are unused by default.  Users may give explicit tag
  4000 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4001 interpretation of tags is determined by the LaTeX job during document
  4002 preparation: see option -V of isatool usedir, or options -n and -t of
  4003 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4004 \isadroptag.
  4005 
  4006 Several document versions may be produced at the same time via isatool
  4007 usedir (the generated index.html will link all of them).  Typical
  4008 specifications include ''-V document=theory,proof,ML'' to present
  4009 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4010 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4011 these parts without any formal replacement text.  The Isabelle site
  4012 default settings produce ''document'' and ''outline'' versions as
  4013 specified above.
  4014 
  4015 * Several new antiquotations:
  4016 
  4017   @{term_type term} prints a term with its type annotated;
  4018 
  4019   @{typeof term} prints the type of a term;
  4020 
  4021   @{const const} is the same as @{term const}, but checks that the
  4022   argument is a known logical constant;
  4023 
  4024   @{term_style style term} and @{thm_style style thm} print a term or
  4025   theorem applying a "style" to it
  4026 
  4027   @{ML text}
  4028 
  4029 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4030 definitions, equations, inequations etc., 'concl' printing only the
  4031 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4032 to print the specified premise.  TermStyle.add_style provides an ML
  4033 interface for introducing further styles.  See also the "LaTeX Sugar"
  4034 document practical applications.  The ML antiquotation prints
  4035 type-checked ML expressions verbatim.
  4036 
  4037 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4038 and 'text' support optional locale specification '(in loc)', which
  4039 specifies the default context for interpreting antiquotations.  For
  4040 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4041 
  4042 * Option 'locale=NAME' of antiquotations specifies an alternative
  4043 context interpreting the subsequent argument.  For example: @{thm
  4044 [locale=lattice] inf_assoc}.
  4045 
  4046 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4047 a proof context.
  4048 
  4049 * Proper output of antiquotations for theory commands involving a
  4050 proof context (such as 'locale' or 'theorem (in loc) ...').
  4051 
  4052 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4053 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4054 
  4055 * isatool usedir: new option -C (default true) controls whether option
  4056 -D should include a copy of the original document directory; -C false
  4057 prevents unwanted effects such as copying of administrative CVS data.
  4058 
  4059 
  4060 *** Pure ***
  4061 
  4062 * Considerably improved version of 'constdefs' command.  Now performs
  4063 automatic type-inference of declared constants; additional support for
  4064 local structure declarations (cf. locales and HOL records), see also
  4065 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4066 sequential dependencies of definitions within a single 'constdefs'
  4067 section; moreover, the declared name needs to be an identifier.  If
  4068 all fails, consider to fall back on 'consts' and 'defs' separately.
  4069 
  4070 * Improved indexed syntax and implicit structures.  First of all,
  4071 indexed syntax provides a notational device for subscripted
  4072 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4073 expressions.  Secondly, in a local context with structure
  4074 declarations, number indexes \<^sub>n or the empty index (default
  4075 number 1) refer to a certain fixed variable implicitly; option
  4076 show_structs controls printing of implicit structures.  Typical
  4077 applications of these concepts involve record types and locales.
  4078 
  4079 * New command 'no_syntax' removes grammar declarations (and
  4080 translations) resulting from the given syntax specification, which is
  4081 interpreted in the same manner as for the 'syntax' command.
  4082 
  4083 * 'Advanced' translation functions (parse_translation etc.) may depend
  4084 on the signature of the theory context being presently used for
  4085 parsing/printing, see also isar-ref manual.
  4086 
  4087 * Improved 'oracle' command provides a type-safe interface to turn an
  4088 ML expression of type theory -> T -> term into a primitive rule of
  4089 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4090 is already included here); see also FOL/ex/IffExample.thy;
  4091 INCOMPATIBILITY.
  4092 
  4093 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4094 before); "cI" is no longer bound, use "c.intro" instead.
  4095 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4096 axclasses vs. locales.
  4097 
  4098 * Improved internal renaming of symbolic identifiers -- attach primes
  4099 instead of base 26 numbers.
  4100 
  4101 * New flag show_question_marks controls printing of leading question
  4102 marks in schematic variable names.
  4103 
  4104 * In schematic variable names, *any* symbol following \<^isub> or
  4105 \<^isup> is now treated as part of the base name.  For example, the
  4106 following works without printing of awkward ".0" indexes:
  4107 
  4108   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4109     by simp
  4110 
  4111 * Inner syntax includes (*(*nested*) comments*).
  4112 
  4113 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4114 annotations as "(00...)".
  4115 
  4116 * Clear separation of logical types and nonterminals, where the latter
  4117 may only occur in 'syntax' specifications or type abbreviations.
  4118 Before that distinction was only partially implemented via type class
  4119 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4120 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4121 exotic syntax specifications may require further adaption
  4122 (e.g. Cube/Cube.thy).
  4123 
  4124 * Removed obsolete type class "logic", use the top sort {} instead.
  4125 Note that non-logical types should be declared as 'nonterminals'
  4126 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4127 specifications.
  4128 
  4129 * Attributes 'induct' and 'cases': type or set names may now be
  4130 locally fixed variables as well.
  4131 
  4132 * Simplifier: can now control the depth to which conditional rewriting
  4133 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4134 Limit.
  4135 
  4136 * Simplifier: simplification procedures may now take the current
  4137 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4138 interface), which is very useful for calling the Simplifier
  4139 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4140 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4141 low-level mk_simproc no longer applies Logic.varify internally, to
  4142 allow for use in a context of fixed variables.
  4143 
  4144 * thin_tac now works even if the assumption being deleted contains !!
  4145 or ==>.  More generally, erule now works even if the major premise of
  4146 the elimination rule contains !! or ==>.
  4147 
  4148 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4149 
  4150 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4151 from Pure, which contains all common declarations already.  Both
  4152 theories are defined via plain Isabelle/Isar .thy files.
  4153 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4154 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4155 use isatool fixcpure to adapt your theory and ML sources.
  4156 
  4157 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4158 selections of theorems in named facts via index ranges.
  4159 
  4160 * 'print_theorems': in theory mode, really print the difference
  4161 wrt. the last state (works for interactive theory development only),
  4162 in proof mode print all local facts (cf. 'print_facts');
  4163 
  4164 * 'hide': option '(open)' hides only base names.
  4165 
  4166 * More efficient treatment of intermediate checkpoints in interactive
  4167 theory development.
  4168 
  4169 * Code generator is now invoked via code_module (incremental code
  4170 generation) and code_library (modular code generation, ML structures
  4171 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4172 must be quoted when used as identifiers.
  4173 
  4174 * New 'value' command for reading, evaluating and printing terms using
  4175 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4176 quoted when used as identifier.
  4177 
  4178 
  4179 *** Locales ***
  4180 
  4181 * New commands for the interpretation of locale expressions in
  4182 theories (1), locales (2) and proof contexts (3).  These generate
  4183 proof obligations from the expression specification.  After the
  4184 obligations have been discharged, theorems of the expression are added
  4185 to the theory, target locale or proof context.  The synopsis of the
  4186 commands is a follows:
  4187 
  4188   (1) interpretation expr inst
  4189   (2) interpretation target < expr
  4190   (3) interpret expr inst
  4191 
  4192 Interpretation in theories and proof contexts require a parameter
  4193 instantiation of terms from the current context.  This is applied to
  4194 specifications and theorems of the interpreted expression.
  4195 Interpretation in locales only permits parameter renaming through the
  4196 locale expression.  Interpretation is smart in that interpretations
  4197 that are active already do not occur in proof obligations, neither are
  4198 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4199 inspect active interpretations of a particular locale.  For details,
  4200 see the Isar Reference manual.  Examples can be found in
  4201 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4202 
  4203 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4204 'interpret' instead.
  4205 
  4206 * New context element 'constrains' for adding type constraints to
  4207 parameters.
  4208 
  4209 * Context expressions: renaming of parameters with syntax
  4210 redeclaration.
  4211 
  4212 * Locale declaration: 'includes' disallowed.
  4213 
  4214 * Proper static binding of attribute syntax -- i.e. types / terms /
  4215 facts mentioned as arguments are always those of the locale definition
  4216 context, independently of the context of later invocations.  Moreover,
  4217 locale operations (renaming and type / term instantiation) are applied
  4218 to attribute arguments as expected.
  4219 
  4220 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4221 actual attributes; rare situations may require Attrib.attribute to
  4222 embed those attributes into Attrib.src that lack concrete syntax.
  4223 Attribute implementations need to cooperate properly with the static
  4224 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4225 Attrib.XXX_thm etc. already do the right thing without further
  4226 intervention.  Only unusual applications -- such as "where" or "of"
  4227 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4228 on the context and the facts involved -- may have to assign parsed
  4229 values to argument tokens explicitly.
  4230 
  4231 * Changed parameter management in theorem generation for long goal
  4232 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4233 theorem statement in rare situations.
  4234 
  4235 * Locale inspection command 'print_locale' omits notes elements.  Use
  4236 'print_locale!' to have them included in the output.
  4237 
  4238 
  4239 *** Provers ***
  4240 
  4241 * Provers/hypsubst.ML: improved version of the subst method, for
  4242 single-step rewriting: it now works in bound variable contexts. New is
  4243 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4244 rewrite a different subterm than the original subst method, which is
  4245 still available as 'simplesubst'.
  4246 
  4247 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4248 and quasi orders.
  4249 
  4250 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4251 reflexive-transitive closure of relations.
  4252 
  4253 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4254 limit (previously hard-coded with a value of 20) user-definable.
  4255 
  4256 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4257 is peformed already.  Object-logics merely need to finish their
  4258 initial simpset configuration as before.  INCOMPATIBILITY.
  4259 
  4260 
  4261 *** HOL ***
  4262 
  4263 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4264 
  4265   syntax (epsilon)
  4266     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4267 
  4268 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4269 and x-symbol; use option '-m epsilon' to get it actually printed.
  4270 Moreover, the mathematically important symbolic identifier \<epsilon>
  4271 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4272 
  4273 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  4274 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  4275 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  4276 support corresponding Isar calculations.
  4277 
  4278 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  4279 instead of ":".
  4280 
  4281 * theory SetInterval: changed the syntax for open intervals:
  4282 
  4283   Old       New
  4284   {..n(}    {..<n}
  4285   {)n..}    {n<..}
  4286   {m..n(}   {m..<n}
  4287   {)m..n}   {m<..n}
  4288   {)m..n(}  {m<..<n}
  4289 
  4290 The old syntax is still supported but will disappear in the next
  4291 release.  For conversion use the following Emacs search and replace
  4292 patterns (these are not perfect but work quite well):
  4293 
  4294   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  4295   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  4296 
  4297 * Theory Commutative_Ring (in Library): method comm_ring for proving
  4298 equalities in commutative rings; method 'algebra' provides a generic
  4299 interface.
  4300 
  4301 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  4302 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  4303 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  4304 be a tuple pattern.
  4305 
  4306 Some new syntax forms are available:
  4307 
  4308   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  4309   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  4310   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  4311   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  4312 
  4313 The latter form "\<Sum>x < k. e" used to be based on a separate
  4314 function "Summation", which has been discontinued.
  4315 
  4316 * theory Finite_Set: in structured induction proofs, the insert case
  4317 is now 'case (insert x F)' instead of the old counterintuitive 'case
  4318 (insert F x)'.
  4319 
  4320 * The 'refute' command has been extended to support a much larger
  4321 fragment of HOL, including axiomatic type classes, constdefs and
  4322 typedefs, inductive datatypes and recursion.
  4323 
  4324 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  4325 Requires zChaff with proof generation to be installed.  See
  4326 HOL/ex/SAT_Examples.thy for examples.
  4327 
  4328 * Datatype induction via method 'induct' now preserves the name of the
  4329 induction variable. For example, when proving P(xs::'a list) by
  4330 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  4331 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  4332 in unstructured proof scripts.
  4333 
  4334 * Reworked implementation of records.  Improved scalability for
  4335 records with many fields, avoiding performance problems for type
  4336 inference. Records are no longer composed of nested field types, but
  4337 of nested extension types. Therefore the record type only grows linear
  4338 in the number of extensions and not in the number of fields.  The
  4339 top-level (users) view on records is preserved.  Potential
  4340 INCOMPATIBILITY only in strange cases, where the theory depends on the
  4341 old record representation. The type generated for a record is called
  4342 <record_name>_ext_type.
  4343 
  4344 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  4345 proofs triggered by a record definition or a simproc (if
  4346 quick_and_dirty is enabled).  Definitions of large records can take
  4347 quite long.
  4348 
  4349 New simproc record_upd_simproc for simplification of multiple record
  4350 updates enabled by default.  Moreover, trivial updates are also
  4351 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  4352 occasionally, since simplification is more powerful by default.
  4353 
  4354 * typedef: proper support for polymorphic sets, which contain extra
  4355 type-variables in the term.
  4356 
  4357 * Simplifier: automatically reasons about transitivity chains
  4358 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  4359 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  4360 old proofs break occasionally as simplification may now solve more
  4361 goals than previously.
  4362 
  4363 * Simplifier: converts x <= y into x = y if assumption y <= x is
  4364 present.  Works for all partial orders (class "order"), in particular
  4365 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  4366 just like y <= x.
  4367 
  4368 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  4369 bound variable or a constant then the let is unfolded.  Otherwise
  4370 first a is simplified to b, and then f b is simplified to g. If
  4371 possible we abstract b from g arriving at "let x = b in h x",
  4372 otherwise we unfold the let and arrive at g.  The simproc can be
  4373 enabled/disabled by the reference use_let_simproc.  Potential
  4374 INCOMPATIBILITY since simplification is more powerful by default.
  4375 
  4376 * Classical reasoning: the meson method now accepts theorems as arguments.
  4377 
  4378 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  4379 jobs to provide advice on the provability of subgoals.
  4380 
  4381 * Theory OrderedGroup and Ring_and_Field: various additions and
  4382 improvements to faciliate calculations involving equalities and
  4383 inequalities.
  4384 
  4385 The following theorems have been eliminated or modified
  4386 (INCOMPATIBILITY):
  4387 
  4388   abs_eq             now named abs_of_nonneg
  4389   abs_of_ge_0        now named abs_of_nonneg
  4390   abs_minus_eq       now named abs_of_nonpos
  4391   imp_abs_id         now named abs_of_nonneg
  4392   imp_abs_neg_id     now named abs_of_nonpos
  4393   mult_pos           now named mult_pos_pos
  4394   mult_pos_le        now named mult_nonneg_nonneg
  4395   mult_pos_neg_le    now named mult_nonneg_nonpos
  4396   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  4397   mult_neg           now named mult_neg_neg
  4398   mult_neg_le        now named mult_nonpos_nonpos
  4399 
  4400 * The following lemmas in Ring_and_Field have been added to the simplifier:
  4401      
  4402      zero_le_square
  4403      not_square_less_zero 
  4404 
  4405   The following lemmas have been deleted from Real/RealPow:
  4406   
  4407      realpow_zero_zero
  4408      realpow_two
  4409      realpow_less
  4410      zero_le_power
  4411      realpow_two_le
  4412      abs_realpow_two
  4413      realpow_two_abs     
  4414 
  4415 * Theory Parity: added rules for simplifying exponents.
  4416 
  4417 * Theory List:
  4418 
  4419 The following theorems have been eliminated or modified
  4420 (INCOMPATIBILITY):
  4421 
  4422   list_all_Nil       now named list_all.simps(1)
  4423   list_all_Cons      now named list_all.simps(2)
  4424   list_all_conv      now named list_all_iff
  4425   set_mem_eq         now named mem_iff
  4426 
  4427 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  4428 asymptotic "big O" calculations.  See the notes in BigO.thy.
  4429 
  4430 
  4431 *** HOL-Complex ***
  4432 
  4433 * Theory RealDef: better support for embedding natural numbers and
  4434 integers in the reals.
  4435 
  4436 The following theorems have been eliminated or modified
  4437 (INCOMPATIBILITY):
  4438 
  4439   exp_ge_add_one_self  now requires no hypotheses
  4440   real_of_int_add      reversed direction of equality (use [symmetric])
  4441   real_of_int_minus    reversed direction of equality (use [symmetric])
  4442   real_of_int_diff     reversed direction of equality (use [symmetric])
  4443   real_of_int_mult     reversed direction of equality (use [symmetric])
  4444 
  4445 * Theory RComplete: expanded support for floor and ceiling functions.
  4446 
  4447 * Theory Ln is new, with properties of the natural logarithm
  4448 
  4449 * Hyperreal: There is a new type constructor "star" for making
  4450 nonstandard types.  The old type names are now type synonyms:
  4451 
  4452   hypreal = real star
  4453   hypnat = nat star
  4454   hcomplex = complex star
  4455 
  4456 * Hyperreal: Many groups of similarly-defined constants have been
  4457 replaced by polymorphic versions (INCOMPATIBILITY):
  4458 
  4459   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  4460 
  4461   starset      <-- starsetNat, starsetC
  4462   *s*          <-- *sNat*, *sc*
  4463   starset_n    <-- starsetNat_n, starsetC_n
  4464   *sn*         <-- *sNatn*, *scn*
  4465   InternalSets <-- InternalNatSets, InternalCSets
  4466 
  4467   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  4468   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  4469   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  4470   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  4471   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  4472 
  4473 * Hyperreal: Many type-specific theorems have been removed in favor of
  4474 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  4475 
  4476   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  4477   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  4478   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  4479   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  4480   right_minus <-- hypreal_add_minus
  4481   left_minus <-- {hypreal,hcomplex}_add_minus_left
  4482   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  4483   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  4484   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  4485   mult_1_right <-- hcomplex_mult_one_right
  4486   mult_zero_left <-- hcomplex_mult_zero_left
  4487   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  4488   right_distrib <-- hypnat_add_mult_distrib2
  4489   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  4490   right_inverse <-- hypreal_mult_inverse
  4491   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  4492   order_refl <-- {hypreal,hypnat}_le_refl
  4493   order_trans <-- {hypreal,hypnat}_le_trans
  4494   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  4495   order_less_le <-- {hypreal,hypnat}_less_le
  4496   linorder_linear <-- {hypreal,hypnat}_le_linear
  4497   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  4498   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  4499   add_nonneg_nonneg <-- hypreal_le_add_order
  4500 
  4501 * Hyperreal: Separate theorems having to do with type-specific
  4502 versions of constants have been merged into theorems that apply to the
  4503 new polymorphic constants (INCOMPATIBILITY):
  4504 
  4505   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  4506   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  4507   STAR_Un <-- {STAR,NatStar,STARC}_Un
  4508   STAR_Int <-- {STAR,NatStar,STARC}_Int
  4509   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  4510   STAR_subset <-- {STAR,NatStar,STARC}_subset
  4511   STAR_mem <-- {STAR,NatStar,STARC}_mem
  4512   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  4513   STAR_diff <-- {STAR,STARC}_diff
  4514   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  4515     STARC_hcomplex_of_complex}_image_subset
  4516   starset_n_Un <-- starset{Nat,C}_n_Un
  4517   starset_n_Int <-- starset{Nat,C}_n_Int
  4518   starset_n_Compl <-- starset{Nat,C}_n_Compl
  4519   starset_n_diff <-- starset{Nat,C}_n_diff
  4520   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  4521   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  4522   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  4523   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  4524   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  4525   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  4526   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  4527   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  4528   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  4529   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  4530   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  4531   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  4532   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  4533   starfun_diff <-- starfun{C,RC,CR}_diff
  4534   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  4535   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  4536   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  4537   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  4538   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  4539   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  4540   starfun_Id <-- starfunC_Id
  4541   starfun_approx <-- starfun{Nat,CR}_approx
  4542   starfun_capprox <-- starfun{C,RC}_capprox
  4543   starfun_abs <-- starfunNat_rabs
  4544   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  4545   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  4546   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  4547   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  4548   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  4549   starfun_add_approx <-- starfunCR_add_approx
  4550   starfun_inverse_inverse <-- starfunC_inverse_inverse
  4551   starfun_divide <-- starfun{C,CR,RC}_divide
  4552   starfun_n <-- starfun{Nat,C}_n
  4553   starfun_n_mult <-- starfun{Nat,C}_n_mult
  4554   starfun_n_add <-- starfun{Nat,C}_n_add
  4555   starfun_n_add_minus <-- starfunNat_n_add_minus
  4556   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  4557   starfun_n_minus <-- starfun{Nat,C}_n_minus
  4558   starfun_n_eq <-- starfun{Nat,C}_n_eq
  4559 
  4560   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  4561   star_n_minus <-- {hypreal,hcomplex}_minus
  4562   star_n_diff <-- {hypreal,hcomplex}_diff
  4563   star_n_mult <-- {hypreal,hcomplex}_mult
  4564   star_n_inverse <-- {hypreal,hcomplex}_inverse
  4565   star_n_le <-- {hypreal,hypnat}_le
  4566   star_n_less <-- {hypreal,hypnat}_less
  4567   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  4568   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  4569   star_n_abs <-- hypreal_hrabs
  4570   star_n_divide <-- hcomplex_divide
  4571 
  4572   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  4573   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  4574   star_of_diff <-- hypreal_of_real_diff
  4575   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  4576   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  4577   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  4578   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  4579   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  4580   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  4581   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  4582   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  4583   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  4584   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  4585   star_of_number_of <-- {hypreal,hcomplex}_number_of
  4586   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  4587   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  4588   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  4589   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  4590   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  4591   star_of_power <-- hypreal_of_real_power
  4592   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  4593 
  4594 * Hyperreal: new method "transfer" that implements the transfer
  4595 principle of nonstandard analysis. With a subgoal that mentions
  4596 nonstandard types like "'a star", the command "apply transfer"
  4597 replaces it with an equivalent one that mentions only standard types.
  4598 To be successful, all free variables must have standard types; non-
  4599 standard variables must have explicit universal quantifiers.
  4600 
  4601 * Hyperreal: A theory of Taylor series.
  4602 
  4603 
  4604 *** HOLCF ***
  4605 
  4606 * Discontinued special version of 'constdefs' (which used to support
  4607 continuous functions) in favor of the general Pure one with full
  4608 type-inference.
  4609 
  4610 * New simplification procedure for solving continuity conditions; it
  4611 is much faster on terms with many nested lambda abstractions (cubic
  4612 instead of exponential time).
  4613 
  4614 * New syntax for domain package: selector names are now optional.
  4615 Parentheses should be omitted unless argument is lazy, for example:
  4616 
  4617   domain 'a stream = cons "'a" (lazy "'a stream")
  4618 
  4619 * New command 'fixrec' for defining recursive functions with pattern
  4620 matching; defining multiple functions with mutual recursion is also
  4621 supported.  Patterns may include the constants cpair, spair, up, sinl,
  4622 sinr, or any data constructor defined by the domain package. The given
  4623 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  4624 syntax and examples.
  4625 
  4626 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  4627 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  4628 but the proof obligation additionally includes an admissibility
  4629 requirement. The packages generate instances of class cpo or pcpo,
  4630 with continuity and strictness theorems for Rep and Abs.
  4631 
  4632 * HOLCF: Many theorems have been renamed according to a more standard naming
  4633 scheme (INCOMPATIBILITY):
  4634 
  4635   foo_inject:  "foo$x = foo$y ==> x = y"
  4636   foo_eq:      "(foo$x = foo$y) = (x = y)"
  4637   foo_less:    "(foo$x << foo$y) = (x << y)"
  4638   foo_strict:  "foo$UU = UU"
  4639   foo_defined: "... ==> foo$x ~= UU"
  4640   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  4641 
  4642 
  4643 *** ZF ***
  4644 
  4645 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  4646 including the First Isomorphism Theorem (on quotienting by the kernel
  4647 of a homomorphism).
  4648 
  4649 * ZF/Simplifier: install second copy of type solver that actually
  4650 makes use of TC rules declared to Isar proof contexts (or locales);
  4651 the old version is still required for ML proof scripts.
  4652 
  4653 
  4654 *** Cube ***
  4655 
  4656 * Converted to Isar theory format; use locales instead of axiomatic
  4657 theories.
  4658 
  4659 
  4660 *** ML ***
  4661 
  4662 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  4663 for ||>, ||>>, |>>,
  4664 
  4665 * Pure/library.ML no longer defines its own option datatype, but uses
  4666 that of the SML basis, which has constructors NONE and SOME instead of
  4667 None and Some, as well as exception Option.Option instead of OPTION.
  4668 The functions the, if_none, is_some, is_none have been adapted
  4669 accordingly, while Option.map replaces apsome.
  4670 
  4671 * Pure/library.ML: the exception LIST has been given up in favour of
  4672 the standard exceptions Empty and Subscript, as well as
  4673 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  4674 superceded by the standard hd and tl functions etc.
  4675 
  4676 A number of basic list functions are no longer exported to the ML
  4677 toplevel, as they are variants of predefined functions.  The following
  4678 suggests how one can translate existing code:
  4679 
  4680     rev_append xs ys = List.revAppend (xs, ys)
  4681     nth_elem (i, xs) = List.nth (xs, i)
  4682     last_elem xs = List.last xs
  4683     flat xss = List.concat xss
  4684     seq fs = List.app fs
  4685     partition P xs = List.partition P xs
  4686     mapfilter f xs = List.mapPartial f xs
  4687 
  4688 * Pure/library.ML: several combinators for linear functional
  4689 transformations, notably reverse application and composition:
  4690 
  4691   x |> f                f #> g
  4692   (x, y) |-> f          f #-> g
  4693 
  4694 * Pure/library.ML: introduced/changed precedence of infix operators:
  4695 
  4696   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  4697   infix 2 ?;
  4698   infix 3 o oo ooo oooo;
  4699   infix 4 ~~ upto downto;
  4700 
  4701 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  4702 infix operators.
  4703 
  4704 * Pure/library.ML: natural list combinators fold, fold_rev, and
  4705 fold_map support linear functional transformations and nesting.  For
  4706 example:
  4707 
  4708   fold f [x1, ..., xN] y =
  4709     y |> f x1 |> ... |> f xN
  4710 
  4711   (fold o fold) f [xs1, ..., xsN] y =
  4712     y |> fold f xs1 |> ... |> fold f xsN
  4713 
  4714   fold f [x1, ..., xN] =
  4715     f x1 #> ... #> f xN
  4716 
  4717   (fold o fold) f [xs1, ..., xsN] =
  4718     fold f xs1 #> ... #> fold f xsN
  4719 
  4720 * Pure/library.ML: the following selectors on type 'a option are
  4721 available:
  4722 
  4723   the:               'a option -> 'a  (*partial*)
  4724   these:             'a option -> 'a  where 'a = 'b list
  4725   the_default: 'a -> 'a option -> 'a
  4726   the_list:          'a option -> 'a list
  4727 
  4728 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  4729 basic operations for association lists, following natural argument
  4730 order; moreover the explicit equality predicate passed here avoids
  4731 potentially expensive polymorphic runtime equality checks.
  4732 The old functions may be expressed as follows:
  4733 
  4734   assoc = uncurry (AList.lookup (op =))
  4735   assocs = these oo AList.lookup (op =)
  4736   overwrite = uncurry (AList.update (op =)) o swap
  4737 
  4738 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  4739 
  4740   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  4741   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  4742 
  4743 replacing make_keylist and keyfilter (occassionally used)
  4744 Naive rewrites:
  4745 
  4746   make_keylist = AList.make
  4747   keyfilter = AList.find (op =)
  4748 
  4749 * eq_fst and eq_snd now take explicit equality parameter, thus
  4750   avoiding eqtypes. Naive rewrites:
  4751 
  4752     eq_fst = eq_fst (op =)
  4753     eq_snd = eq_snd (op =)
  4754 
  4755 * Removed deprecated apl and apr (rarely used).
  4756   Naive rewrites:
  4757 
  4758     apl (n, op) =>>= curry op n
  4759     apr (op, m) =>>= fn n => op (n, m)
  4760 
  4761 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  4762 provides a reasonably efficient light-weight implementation of sets as
  4763 lists.
  4764 
  4765 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  4766 few new operations; existing lookup and update are now curried to
  4767 follow natural argument order (for use with fold etc.);
  4768 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  4769 
  4770 * Pure/General: output via the Isabelle channels of
  4771 writeln/warning/error etc. is now passed through Output.output, with a
  4772 hook for arbitrary transformations depending on the print_mode
  4773 (cf. Output.add_mode -- the first active mode that provides a output
  4774 function wins).  Already formatted output may be embedded into further
  4775 text via Output.raw; the result of Pretty.string_of/str_of and derived
  4776 functions (string_of_term/cterm/thm etc.) is already marked raw to
  4777 accommodate easy composition of diagnostic messages etc.  Programmers
  4778 rarely need to care about Output.output or Output.raw at all, with
  4779 some notable exceptions: Output.output is required when bypassing the
  4780 standard channels (writeln etc.), or in token translations to produce
  4781 properly formatted results; Output.raw is required when capturing
  4782 already output material that will eventually be presented to the user
  4783 a second time.  For the default print mode, both Output.output and
  4784 Output.raw have no effect.
  4785 
  4786 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  4787 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  4788 cumulative results are displayed at the end of a batch session.
  4789 
  4790 * Pure/General: File.sysify_path and File.quote_sysify path have been
  4791 replaced by File.platform_path and File.shell_path (with appropriate
  4792 hooks).  This provides a clean interface for unusual systems where the
  4793 internal and external process view of file names are different.
  4794 
  4795 * Pure: more efficient orders for basic syntactic entities: added
  4796 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  4797 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  4798 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  4799 orders now -- potential INCOMPATIBILITY for code that depends on a
  4800 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  4801 Library.sort_strings on result).
  4802 
  4803 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  4804 fold_types traverse types/terms from left to right, observing natural
  4805 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  4806 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  4807 
  4808 * Pure: name spaces have been refined, with significant changes of the
  4809 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  4810 to extern(_table).  The plain name entry path is superceded by a
  4811 general 'naming' context, which also includes the 'policy' to produce
  4812 a fully qualified name and external accesses of a fully qualified
  4813 name; NameSpace.extend is superceded by context dependent
  4814 Sign.declare_name.  Several theory and proof context operations modify
  4815 the naming context.  Especially note Theory.restore_naming and
  4816 ProofContext.restore_naming to get back to a sane state; note that
  4817 Theory.add_path is no longer sufficient to recover from
  4818 Theory.absolute_path in particular.
  4819 
  4820 * Pure: new flags short_names (default false) and unique_names
  4821 (default true) for controlling output of qualified names.  If
  4822 short_names is set, names are printed unqualified.  If unique_names is
  4823 reset, the name prefix is reduced to the minimum required to achieve
  4824 the original result when interning again, even if there is an overlap
  4825 with earlier declarations.
  4826 
  4827 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  4828 now 'extend', and 'merge' gets an additional Pretty.pp argument
  4829 (useful for printing error messages).  INCOMPATIBILITY.
  4830 
  4831 * Pure: major reorganization of the theory context.  Type Sign.sg and
  4832 Theory.theory are now identified, referring to the universal
  4833 Context.theory (see Pure/context.ML).  Actual signature and theory
  4834 content is managed as theory data.  The old code and interfaces were
  4835 spread over many files and structures; the new arrangement introduces
  4836 considerable INCOMPATIBILITY to gain more clarity:
  4837 
  4838   Context -- theory management operations (name, identity, inclusion,
  4839     parents, ancestors, merge, etc.), plus generic theory data;
  4840 
  4841   Sign -- logical signature and syntax operations (declaring consts,
  4842     types, etc.), plus certify/read for common entities;
  4843 
  4844   Theory -- logical theory operations (stating axioms, definitions,
  4845     oracles), plus a copy of logical signature operations (consts,
  4846     types, etc.); also a few basic management operations (Theory.copy,
  4847     Theory.merge, etc.)
  4848 
  4849 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  4850 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  4851 for convenience -- they merely return the theory.
  4852 
  4853 * Pure: type Type.tsig is superceded by theory in most interfaces.
  4854 
  4855 * Pure: the Isar proof context type is already defined early in Pure
  4856 as Context.proof (note that ProofContext.context and Proof.context are
  4857 aliases, where the latter is the preferred name).  This enables other
  4858 Isabelle components to refer to that type even before Isar is present.
  4859 
  4860 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  4861 typeK, constK, axiomK, oracleK), but provide explicit operations for
  4862 any of these kinds.  For example, Sign.intern typeK is now
  4863 Sign.intern_type, Theory.hide_space Sign.typeK is now
  4864 Theory.hide_types.  Also note that former
  4865 Theory.hide_classes/types/consts are now
  4866 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  4867 internalize their arguments!  INCOMPATIBILITY.
  4868 
  4869 * Pure: get_thm interface (of PureThy and ProofContext) expects
  4870 datatype thmref (with constructors Name and NameSelection) instead of
  4871 plain string -- INCOMPATIBILITY;
  4872 
  4873 * Pure: cases produced by proof methods specify options, where NONE
  4874 means to remove case bindings -- INCOMPATIBILITY in
  4875 (RAW_)METHOD_CASES.
  4876 
  4877 * Pure: the following operations retrieve axioms or theorems from a
  4878 theory node or theory hierarchy, respectively:
  4879 
  4880   Theory.axioms_of: theory -> (string * term) list
  4881   Theory.all_axioms_of: theory -> (string * term) list
  4882   PureThy.thms_of: theory -> (string * thm) list
  4883   PureThy.all_thms_of: theory -> (string * thm) list
  4884 
  4885 * Pure: print_tac now outputs the goal through the trace channel.
  4886 
  4887 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  4888 Reference Toplevel.debug (default false) controls detailed printing
  4889 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  4890 controls execution profiling -- set to 1 for time and 2 for space
  4891 (both increase the runtime).
  4892 
  4893 * Isar session: The initial use of ROOT.ML is now always timed,
  4894 i.e. the log will show the actual process times, in contrast to the
  4895 elapsed wall-clock time that the outer shell wrapper produces.
  4896 
  4897 * Simplifier: improved handling of bound variables (nameless
  4898 representation, avoid allocating new strings).  Simprocs that invoke
  4899 the Simplifier recursively should use Simplifier.inherit_bounds to
  4900 avoid local name clashes.  Failure to do so produces warnings
  4901 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  4902 for further details.
  4903 
  4904 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  4905 bindings for all theorems stored within a given theory; this may help
  4906 in porting non-Isar theories to Isar ones, while keeping ML proof
  4907 scripts for the time being.
  4908 
  4909 * ML operator HTML.with_charset specifies the charset begin used for
  4910 generated HTML files.  For example:
  4911 
  4912   HTML.with_charset "utf-8" use_thy "Hebrew";
  4913   HTML.with_charset "utf-8" use_thy "Chinese";
  4914 
  4915 
  4916 *** System ***
  4917 
  4918 * Allow symlinks to all proper Isabelle executables (Isabelle,
  4919 isabelle, isatool etc.).
  4920 
  4921 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  4922 isatool doc, isatool mkdir, display_drafts etc.).
  4923 
  4924 * isatool usedir: option -f allows specification of the ML file to be
  4925 used by Isabelle; default is ROOT.ML.
  4926 
  4927 * New isatool version outputs the version identifier of the Isabelle
  4928 distribution being used.
  4929 
  4930 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  4931 (containing Boolean satisfiability problems) into Isabelle/HOL
  4932 theories.
  4933 
  4934 
  4935 
  4936 New in Isabelle2004 (April 2004)
  4937 --------------------------------
  4938 
  4939 *** General ***
  4940 
  4941 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  4942   Replaces linorder.ML.
  4943 
  4944 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  4945   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  4946   (\<a>...\<z>), are now considered normal letters, and can therefore
  4947   be used anywhere where an ASCII letter (a...zA...Z) has until
  4948   now. COMPATIBILITY: This obviously changes the parsing of some
  4949   terms, especially where a symbol has been used as a binder, say
  4950   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  4951   as an identifier.  Fix it by inserting a space around former
  4952   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  4953   existing theory and ML files.
  4954 
  4955 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  4956 
  4957 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  4958   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  4959   a normal (but invisible) letter. For multiple letter subscripts repeat
  4960   \<^isub> like this: x\<^isub>1\<^isub>2.
  4961 
  4962 * Pure: There are now sub-/superscripts that can span more than one
  4963   character. Text between \<^bsub> and \<^esub> is set in subscript in
  4964   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  4965   superscript. The new control characters are not identifier parts.
  4966 
  4967 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  4968   content of "..." to the latex file instead of \isacntrl... . The "..."
  4969   may consist of any printable characters excluding the end bracket >.
  4970 
  4971 * Pure: Using new Isar command "finalconsts" (or the ML functions
  4972   Theory.add_finals or Theory.add_finals_i) it is now possible to
  4973   declare constants "final", which prevents their being given a definition
  4974   later.  It is useful for constants whose behaviour is fixed axiomatically
  4975   rather than definitionally, such as the meta-logic connectives.
  4976 
  4977 * Pure: 'instance' now handles general arities with general sorts
  4978   (i.e. intersections of classes),
  4979 
  4980 * Presentation: generated HTML now uses a CSS style sheet to make layout
  4981   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  4982   It can be changed to alter the colors/layout of generated pages.
  4983 
  4984 
  4985 *** Isar ***
  4986 
  4987 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  4988   cut_tac, subgoal_tac and thin_tac:
  4989   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  4990     locales are no longer forced to write Isar proof scripts.
  4991     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  4992     emulations.
  4993   - INCOMPATIBILITY: names of variables to be instantiated may no
  4994     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  4995     This is consistent with the instantiation attribute "where".
  4996 
  4997 * Attributes "where" and "of":
  4998   - Now take type variables of instantiated theorem into account when reading
  4999     the instantiation string.  This fixes a bug that caused instantiated
  5000     theorems to have too special types in some circumstances.
  5001   - "where" permits explicit instantiations of type variables.
  5002 
  5003 * Calculation commands "moreover" and "also" no longer interfere with
  5004   current facts ("this"), admitting arbitrary combinations with "then"
  5005   and derived forms.
  5006 
  5007 * Locales:
  5008   - Goal statements involving the context element "includes" no longer
  5009     generate theorems with internal delta predicates (those ending on
  5010     "_axioms") in the premise.
  5011     Resolve particular premise with <locale>.intro to obtain old form.
  5012   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5013     specification and "includes" elements in goal statement.
  5014   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5015     [intro?] and [elim?] (respectively) by default.
  5016   - Experimental command for instantiation of locales in proof contexts:
  5017         instantiate <label>[<attrs>]: <loc>
  5018     Instantiates locale <loc> and adds all its theorems to the current context
  5019     taking into account their attributes.  Label and attrs are optional
  5020     modifiers, like in theorem declarations.  If present, names of
  5021     instantiated theorems are qualified with <label>, and the attributes
  5022     <attrs> are applied after any attributes these theorems might have already.
  5023       If the locale has assumptions, a chained fact of the form
  5024     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5025     are derived.  The command does not support old-style locales declared
  5026     with "locale (open)".
  5027       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5028 
  5029 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5030   (Isar) contexts.
  5031 
  5032 
  5033 *** HOL ***
  5034 
  5035 * Proof import: new image HOL4 contains the imported library from
  5036   the HOL4 system with about 2500 theorems. It is imported by
  5037   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5038   can be used like any other Isabelle image.  See
  5039   HOL/Import/HOL/README for more information.
  5040 
  5041 * Simplifier:
  5042   - Much improved handling of linear and partial orders.
  5043     Reasoners for linear and partial orders are set up for type classes
  5044     "linorder" and "order" respectively, and are added to the default simpset
  5045     as solvers.  This means that the simplifier can build transitivity chains
  5046     to solve goals from the assumptions.
  5047   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5048     of blast or auto after simplification become unnecessary because the goal
  5049     is solved by simplification already.
  5050 
  5051 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5052     all proved in axiomatic type classes for semirings, rings and fields.
  5053 
  5054 * Numerics:
  5055   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5056     now formalized using the Ring_and_Field theory mentioned above.
  5057   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5058     than before, because now they are set up once in a generic manner.
  5059   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5060     Look for the general versions in Ring_and_Field (and Power if they concern
  5061     exponentiation).
  5062 
  5063 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5064 
  5065 * Records:
  5066   - Record types are now by default printed with their type abbreviation
  5067     instead of the list of all field types. This can be configured via
  5068     the reference "print_record_type_abbr".
  5069   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5070     (not enabled by default).
  5071   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5072     EX x. x = sel r to True (not enabled by default).
  5073   - Tactic "record_split_simp_tac" to split and simplify records added.
  5074 
  5075 * 'specification' command added, allowing for definition by
  5076   specification.  There is also an 'ax_specification' command that
  5077   introduces the new constants axiomatically.
  5078 
  5079 * arith(_tac) is now able to generate counterexamples for reals as well.
  5080 
  5081 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5082 
  5083 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5084   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5085 
  5086 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5087   matrix theory to linear programming.
  5088 
  5089 * Unions and Intersections:
  5090   The latex output syntax of UN and INT has been changed
  5091   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5092   i.e. the index formulae has become a subscript.
  5093   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5094 
  5095 * Unions and Intersections over Intervals:
  5096   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5097   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5098   like in normal math, and corresponding versions for < and for intersection.
  5099 
  5100 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5101   lexicographic dictonary ordering has been added as "lexord".
  5102 
  5103 * ML: the legacy theory structures Int and List have been removed. They had
  5104   conflicted with ML Basis Library structures having the same names.
  5105 
  5106 * 'refute' command added to search for (finite) countermodels.  Only works
  5107   for a fragment of HOL.  The installation of an external SAT solver is
  5108   highly recommended.  See "HOL/Refute.thy" for details.
  5109 
  5110 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5111   formulae under an assignment of free variables to random values.
  5112   In contrast to 'refute', it can deal with inductive datatypes,
  5113   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5114   for examples.
  5115 
  5116 
  5117 *** HOLCF ***
  5118 
  5119 * Streams now come with concatenation and are part of the HOLCF image
  5120 
  5121 
  5122 
  5123 New in Isabelle2003 (May 2003)
  5124 ------------------------------
  5125 
  5126 *** General ***
  5127 
  5128 * Provers/simplifier:
  5129 
  5130   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5131     Assumptions are now subject to complete mutual simplification,
  5132     not just from left to right. The simplifier now preserves
  5133     the order of assumptions.
  5134 
  5135     Potential INCOMPATIBILITY:
  5136 
  5137     -- simp sometimes diverges where the old version did
  5138        not, e.g. invoking simp on the goal
  5139 
  5140         [| P (f x); y = x; f x = f y |] ==> Q
  5141 
  5142        now gives rise to the infinite reduction sequence
  5143 
  5144         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5145 
  5146        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5147        kind of problem.
  5148 
  5149     -- Tactics combining classical reasoner and simplification (such as auto)
  5150        are also affected by this change, because many of them rely on
  5151        simp. They may sometimes diverge as well or yield a different numbers
  5152        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5153        in case of problems. Sometimes subsequent calls to the classical
  5154        reasoner will fail because a preceeding call to the simplifier too
  5155        eagerly simplified the goal, e.g. deleted redundant premises.
  5156 
  5157   - The simplifier trace now shows the names of the applied rewrite rules
  5158 
  5159   - You can limit the number of recursive invocations of the simplifier
  5160     during conditional rewriting (where the simplifie tries to solve the
  5161     conditions before applying the rewrite rule):
  5162     ML "simp_depth_limit := n"
  5163     where n is an integer. Thus you can force termination where previously
  5164     the simplifier would diverge.
  5165 
  5166   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5167 
  5168   - No longer aborts on failed congruence proof.  Instead, the
  5169     congruence is ignored.
  5170 
  5171 * Pure: New generic framework for extracting programs from constructive
  5172   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5173   as HOL/Extraction for some case studies.
  5174 
  5175 * Pure: The main goal of the proof state is no longer shown by default, only
  5176 the subgoals. This behaviour is controlled by a new flag.
  5177    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5178 (ML: Proof.show_main_goal).
  5179 
  5180 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5181 rules whose conclusion matches subgoal 1:
  5182       PG menu: Isabelle/Isar -> Show me -> matching rules
  5183 The rules are ordered by how closely they match the subgoal.
  5184 In particular, rules that solve a subgoal outright are displayed first
  5185 (or rather last, the way they are printed).
  5186 (ML: ProofGeneral.print_intros())
  5187 
  5188 * Pure: New flag trace_unify_fail causes unification to print
  5189 diagnostic information (PG: in trace buffer) when it fails. This is
  5190 useful for figuring out why single step proofs like rule, erule or
  5191 assumption failed.
  5192 
  5193 * Pure: Locale specifications now produce predicate definitions
  5194 according to the body of text (covering assumptions modulo local
  5195 definitions); predicate "loc_axioms" covers newly introduced text,
  5196 while "loc" is cumulative wrt. all included locale expressions; the
  5197 latter view is presented only on export into the global theory
  5198 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5199 on the old view without predicates;
  5200 
  5201 * Pure: predefined locales "var" and "struct" are useful for sharing
  5202 parameters (as in CASL, for example); just specify something like
  5203 ``var x + var y + struct M'' as import;
  5204 
  5205 * Pure: improved thms_containing: proper indexing of facts instead of
  5206 raw theorems; check validity of results wrt. current name space;
  5207 include local facts of proof configuration (also covers active
  5208 locales), cover fixed variables in index; may use "_" in term
  5209 specification; an optional limit for the number of printed facts may
  5210 be given (the default is 40);
  5211 
  5212 * Pure: disallow duplicate fact bindings within new-style theory files
  5213 (batch-mode only);
  5214 
  5215 * Provers: improved induct method: assumptions introduced by case
  5216 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5217 the goal statement); "foo" still refers to all facts collectively;
  5218 
  5219 * Provers: the function blast.overloaded has been removed: all constants
  5220 are regarded as potentially overloaded, which improves robustness in exchange
  5221 for slight decrease in efficiency;
  5222 
  5223 * Provers/linorder: New generic prover for transitivity reasoning over
  5224 linear orders.  Note: this prover is not efficient!
  5225 
  5226 * Isar: preview of problems to finish 'show' now produce an error
  5227 rather than just a warning (in interactive mode);
  5228 
  5229 
  5230 *** HOL ***
  5231 
  5232 * arith(_tac)
  5233 
  5234  - Produces a counter example if it cannot prove a goal.
  5235    Note that the counter example may be spurious if the goal is not a formula
  5236    of quantifier-free linear arithmetic.
  5237    In ProofGeneral the counter example appears in the trace buffer.
  5238 
  5239  - Knows about div k and mod k where k is a numeral of type nat or int.
  5240 
  5241  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5242    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5243    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5244 
  5245 * simp's arithmetic capabilities have been enhanced a bit: it now
  5246 takes ~= in premises into account (by performing a case split);
  5247 
  5248 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5249 are distributed over a sum of terms;
  5250 
  5251 * New tactic "trans_tac" and method "trans" instantiate
  5252 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5253 "<=", "<" and "=").
  5254 
  5255 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5256 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5257 
  5258 * 'typedef' command has new option "open" to suppress the set
  5259 definition;
  5260 
  5261 * functions Min and Max on finite sets have been introduced (theory
  5262 Finite_Set);
  5263 
  5264 * attribute [symmetric] now works for relations as well; it turns
  5265 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5266 
  5267 * induct over a !!-quantified statement (say !!x1..xn):
  5268   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5269 
  5270 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5271 %x. None. Warning: empty_def now refers to the previously hidden definition
  5272 of the empty set.
  5273 
  5274 * Algebra: formalization of classical algebra.  Intended as base for
  5275 any algebraic development in Isabelle.  Currently covers group theory
  5276 (up to Sylow's theorem) and ring theory (Universal Property of
  5277 Univariate Polynomials).  Contributions welcome;
  5278 
  5279 * GroupTheory: deleted, since its material has been moved to Algebra;
  5280 
  5281 * Complex: new directory of the complex numbers with numeric constants,
  5282 nonstandard complex numbers, and some complex analysis, standard and
  5283 nonstandard (Jacques Fleuriot);
  5284 
  5285 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  5286 
  5287 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  5288 Fleuriot);
  5289 
  5290 * Real/HahnBanach: updated and adapted to locales;
  5291 
  5292 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  5293 Gray and Kramer);
  5294 
  5295 * UNITY: added the Meier-Sanders theory of progress sets;
  5296 
  5297 * MicroJava: bytecode verifier and lightweight bytecode verifier
  5298 as abstract algorithms, instantiated to the JVM;
  5299 
  5300 * Bali: Java source language formalization. Type system, operational
  5301 semantics, axiomatic semantics. Supported language features:
  5302 classes, interfaces, objects,virtual methods, static methods,
  5303 static/instance fields, arrays, access modifiers, definite
  5304 assignment, exceptions.
  5305 
  5306 
  5307 *** ZF ***
  5308 
  5309 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  5310 universe, etc.);
  5311 
  5312 * Main ZF: virtually all theories converted to new-style format;
  5313 
  5314 
  5315 *** ML ***
  5316 
  5317 * Pure: Tactic.prove provides sane interface for internal proofs;
  5318 omits the infamous "standard" operation, so this is more appropriate
  5319 than prove_goalw_cterm in many situations (e.g. in simprocs);
  5320 
  5321 * Pure: improved error reporting of simprocs;
  5322 
  5323 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  5324 up simprocs;
  5325 
  5326 
  5327 *** Document preparation ***
  5328 
  5329 * uses \par instead of \\ for line breaks in theory text. This may
  5330 shift some page breaks in large documents. To get the old behaviour
  5331 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  5332 
  5333 * minimized dependencies of isabelle.sty and isabellesym.sty on
  5334 other packages
  5335 
  5336 * \<euro> now needs package babel/greek instead of marvosym (which
  5337 broke \Rightarrow)
  5338 
  5339 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  5340 textcomp package)
  5341 
  5342 
  5343 
  5344 New in Isabelle2002 (March 2002)
  5345 --------------------------------
  5346 
  5347 *** Document preparation ***
  5348 
  5349 * greatly simplified document preparation setup, including more
  5350 graceful interpretation of isatool usedir -i/-d/-D options, and more
  5351 instructive isatool mkdir; users should basically be able to get
  5352 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  5353 users may run a separate document processing stage manually like this:
  5354 "isatool usedir -D output HOL Test && isatool document Test/output";
  5355 
  5356 * theory dependency graph may now be incorporated into documents;
  5357 isatool usedir -g true will produce session_graph.eps/.pdf for use
  5358 with \includegraphics of LaTeX;
  5359 
  5360 * proper spacing of consecutive markup elements, especially text
  5361 blocks after section headings;
  5362 
  5363 * support bold style (for single symbols only), input syntax is like
  5364 this: "\<^bold>\<alpha>" or "\<^bold>A";
  5365 
  5366 * \<bullet> is now output as bold \cdot by default, which looks much
  5367 better in printed text;
  5368 
  5369 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  5370 note that these symbols are currently unavailable in Proof General /
  5371 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  5372 
  5373 * isatool latex no longer depends on changed TEXINPUTS, instead
  5374 isatool document copies the Isabelle style files to the target
  5375 location;
  5376 
  5377 
  5378 *** Isar ***
  5379 
  5380 * Pure/Provers: improved proof by cases and induction;
  5381   - 'case' command admits impromptu naming of parameters (such as
  5382     "case (Suc n)");
  5383   - 'induct' method divinates rule instantiation from the inductive
  5384     claim; no longer requires excessive ?P bindings for proper
  5385     instantiation of cases;
  5386   - 'induct' method properly enumerates all possibilities of set/type
  5387     rules; as a consequence facts may be also passed through *type*
  5388     rules without further ado;
  5389   - 'induct' method now derives symbolic cases from the *rulified*
  5390     rule (before it used to rulify cases stemming from the internal
  5391     atomized version); this means that the context of a non-atomic
  5392     statement becomes is included in the hypothesis, avoiding the
  5393     slightly cumbersome show "PROP ?case" form;
  5394   - 'induct' may now use elim-style induction rules without chaining
  5395     facts, using ``missing'' premises from the goal state; this allows
  5396     rules stemming from inductive sets to be applied in unstructured
  5397     scripts, while still benefitting from proper handling of non-atomic
  5398     statements; NB: major inductive premises need to be put first, all
  5399     the rest of the goal is passed through the induction;
  5400   - 'induct' proper support for mutual induction involving non-atomic
  5401     rule statements (uses the new concept of simultaneous goals, see
  5402     below);
  5403   - append all possible rule selections, but only use the first
  5404     success (no backtracking);
  5405   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  5406   - undeclared rule case names default to numbers 1, 2, 3, ...;
  5407   - added 'print_induct_rules' (covered by help item in recent Proof
  5408     General versions);
  5409   - moved induct/cases attributes to Pure, methods to Provers;
  5410   - generic method setup instantiated for FOL and HOL;
  5411 
  5412 * Pure: support multiple simultaneous goal statements, for example
  5413 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  5414 meta-level mechanism, this acts as if several individual goals had
  5415 been stated separately; in particular common proof methods need to be
  5416 repeated in order to cover all claims; note that a single elimination
  5417 step is *not* sufficient to establish the two conjunctions, so this
  5418 fails:
  5419 
  5420   assume "A & B" then have A and B ..   (*".." fails*)
  5421 
  5422 better use "obtain" in situations as above; alternative refer to
  5423 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  5424 
  5425 * Pure: proper integration with ``locales''; unlike the original
  5426 version by Florian Kammller, Isar locales package high-level proof
  5427 contexts rather than raw logical ones (e.g. we admit to include
  5428 attributes everywhere); operations on locales include merge and
  5429 rename; support for implicit arguments (``structures''); simultaneous
  5430 type-inference over imports and text; see also HOL/ex/Locales.thy for
  5431 some examples;
  5432 
  5433 * Pure: the following commands have been ``localized'', supporting a
  5434 target locale specification "(in name)": 'lemma', 'theorem',
  5435 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  5436 stored both within the locale and at the theory level (exported and
  5437 qualified by the locale name);
  5438 
  5439 * Pure: theory goals may now be specified in ``long'' form, with
  5440 ad-hoc contexts consisting of arbitrary locale elements. for example
  5441 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  5442 definitions may be given, too); the result is a meta-level rule with
  5443 the context elements being discharged in the obvious way;
  5444 
  5445 * Pure: new proof command 'using' allows to augment currently used
  5446 facts after a goal statement ('using' is syntactically analogous to
  5447 'apply', but acts on the goal's facts only); this allows chained facts
  5448 to be separated into parts given before and after a claim, as in
  5449 ``from a and b have C using d and e <proof>'';
  5450 
  5451 * Pure: renamed "antecedent" case to "rule_context";
  5452 
  5453 * Pure: new 'judgment' command records explicit information about the
  5454 object-logic embedding (used by several tools internally); no longer
  5455 use hard-wired "Trueprop";
  5456 
  5457 * Pure: added 'corollary' command;
  5458 
  5459 * Pure: fixed 'token_translation' command;
  5460 
  5461 * Pure: removed obsolete 'exported' attribute;
  5462 
  5463 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  5464 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  5465 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  5466 
  5467 * Pure: method 'atomize' presents local goal premises as object-level
  5468 statements (atomic meta-level propositions); setup controlled via
  5469 rewrite rules declarations of 'atomize' attribute; example
  5470 application: 'induct' method with proper rule statements in improper
  5471 proof *scripts*;
  5472 
  5473 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  5474 now consider the syntactic context of assumptions, giving a better
  5475 chance to get type-inference of the arguments right (this is
  5476 especially important for locales);
  5477 
  5478 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  5479 mode;
  5480 
  5481 * Pure/obtain: the formal conclusion "thesis", being marked as
  5482 ``internal'', may no longer be reference directly in the text;
  5483 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  5484 situations;
  5485 
  5486 * Pure: generic 'sym' attribute which declares a rule both as pure
  5487 'elim?' and for the 'symmetric' operation;
  5488 
  5489 * Pure: marginal comments ``--'' may now occur just anywhere in the
  5490 text; the fixed correlation with particular command syntax has been
  5491 discontinued;
  5492 
  5493 * Pure: new method 'rules' is particularly well-suited for proof
  5494 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  5495 but often produces more compact proof terms with less detours;
  5496 
  5497 * Pure/Provers/classical: simplified integration with pure rule
  5498 attributes and methods; the classical "intro?/elim?/dest?"
  5499 declarations coincide with the pure ones; the "rule" method no longer
  5500 includes classically swapped intros; "intro" and "elim" methods no
  5501 longer pick rules from the context; also got rid of ML declarations
  5502 AddXIs/AddXEs/AddXDs; all of this has some potential for
  5503 INCOMPATIBILITY;
  5504 
  5505 * Provers/classical: attribute 'swapped' produces classical inversions
  5506 of introduction rules;
  5507 
  5508 * Provers/simplifier: 'simplified' attribute may refer to explicit
  5509 rules instead of full simplifier context; 'iff' attribute handles
  5510 conditional rules;
  5511 
  5512 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  5513 
  5514 * HOL: 'recdef' now fails on unfinished automated proofs, use
  5515 "(permissive)" option to recover old behavior;
  5516 
  5517 * HOL: 'inductive' no longer features separate (collective) attributes
  5518 for 'intros' (was found too confusing);
  5519 
  5520 * HOL: properly declared induction rules less_induct and
  5521 wf_induct_rule;
  5522 
  5523 
  5524 *** HOL ***
  5525 
  5526 * HOL: moved over to sane numeral syntax; the new policy is as
  5527 follows:
  5528 
  5529   - 0 and 1 are polymorphic constants, which are defined on any
  5530   numeric type (nat, int, real etc.);
  5531 
  5532   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  5533   binary representation internally;
  5534 
  5535   - type nat has special constructor Suc, and generally prefers Suc 0
  5536   over 1::nat and Suc (Suc 0) over 2::nat;
  5537 
  5538 This change may cause significant problems of INCOMPATIBILITY; here
  5539 are some hints on converting existing sources:
  5540 
  5541   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  5542   entities, so expressions involving "-" (unary or binary minus) need
  5543   to be spaced properly;
  5544 
  5545   - existing occurrences of "1" may need to be constraint "1::nat" or
  5546   even replaced by Suc 0; similar for old "2";
  5547 
  5548   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  5549 
  5550   - remove all special provisions on numerals in proofs;
  5551 
  5552 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  5553 representation (depends on bin_arith_simps in the default context);
  5554 
  5555 * HOL: symbolic syntax for x^2 (numeral 2);
  5556 
  5557 * HOL: the class of all HOL types is now called "type" rather than
  5558 "term"; INCOMPATIBILITY, need to adapt references to this type class
  5559 in axclass/classes, instance/arities, and (usually rare) occurrences
  5560 in typings (of consts etc.); internally the class is called
  5561 "HOL.type", ML programs should refer to HOLogic.typeS;
  5562 
  5563 * HOL/record package improvements:
  5564   - new derived operations "fields" to build a partial record section,
  5565     "extend" to promote a fixed record to a record scheme, and
  5566     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  5567     declared as simp by default;
  5568   - shared operations ("more", "fields", etc.) now need to be always
  5569     qualified) --- potential INCOMPATIBILITY;
  5570   - removed "make_scheme" operations (use "make" with "extend") --
  5571     INCOMPATIBILITY;
  5572   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  5573   - provides cases/induct rules for use with corresponding Isar
  5574     methods (for concrete records, record schemes, concrete more
  5575     parts, and schematic more parts -- in that order);
  5576   - internal definitions directly based on a light-weight abstract
  5577     theory of product types over typedef rather than datatype;
  5578 
  5579 * HOL: generic code generator for generating executable ML code from
  5580 specifications; specific support for HOL constructs such as inductive
  5581 datatypes and sets, as well as recursive functions; can be invoked
  5582 via 'generate_code' theory section;
  5583 
  5584 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  5585 
  5586 * HOL: consolidated and renamed several theories.  In particular:
  5587         Ord.thy has been absorbed into HOL.thy
  5588         String.thy has been absorbed into List.thy
  5589 
  5590 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  5591 (beware of argument permutation!);
  5592 
  5593 * HOL: linorder_less_split superseded by linorder_cases;
  5594 
  5595 * HOL/List: "nodups" renamed to "distinct";
  5596 
  5597 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  5598 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  5599   - Ex_def has changed, now need to use some_eq_ex
  5600 
  5601 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  5602 in this (rare) case use:
  5603 
  5604   delSWrapper "split_all_tac"
  5605   addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
  5606 
  5607 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
  5608 MAY FAIL;
  5609 
  5610 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
  5611 Isabelle's type classes, ^ on functions and relations has too general
  5612 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be
  5613 necessary to attach explicit type constraints;
  5614 
  5615 * HOL/Relation: the prefix name of the infix "O" has been changed from
  5616 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been
  5617 renamed accordingly (eg "compI" -> "rel_compI").
  5618 
  5619 * HOL: syntax translations now work properly with numerals and records
  5620 expressions;
  5621 
  5622 * HOL: bounded abstraction now uses syntax "%" / "\<lambda>" instead
  5623 of "lam" -- INCOMPATIBILITY;
  5624 
  5625 * HOL: got rid of some global declarations (potential INCOMPATIBILITY
  5626 for ML tools): const "()" renamed "Product_Type.Unity", type "unit"
  5627 renamed "Product_Type.unit";
  5628 
  5629 * HOL: renamed rtrancl_into_rtrancl2 to converse_rtrancl_into_rtrancl
  5630 
  5631 * HOL: removed obsolete theorem "optionE" (use "option.exhaust", or
  5632 the "cases" method);
  5633 
  5634 * HOL/GroupTheory: group theory examples including Sylow's theorem (by
  5635 Florian Kammller);
  5636 
  5637 * HOL/IMP: updated and converted to new-style theory format; several
  5638 parts turned into readable document, with proper Isar proof texts and
  5639 some explanations (by Gerwin Klein);
  5640 
  5641 * HOL-Real: added Complex_Numbers (by Gertrud Bauer);
  5642 
  5643 * HOL-Hyperreal is now a logic image;
  5644 
  5645 
  5646 *** HOLCF ***
  5647 
  5648 * Isar: consts/constdefs supports mixfix syntax for continuous
  5649 operations;
  5650 
  5651 * Isar: domain package adapted to new-style theory format, e.g. see
  5652 HOLCF/ex/Dnat.thy;
  5653 
  5654 * theory Lift: proper use of rep_datatype lift instead of ML hacks --
  5655 potential INCOMPATIBILITY; now use plain induct_tac instead of former
  5656 lift.induct_tac, always use UU instead of Undef;
  5657 
  5658 * HOLCF/IMP: updated and converted to new-style theory;
  5659 
  5660 
  5661 *** ZF ***
  5662 
  5663 * Isar: proper integration of logic-specific tools and packages,
  5664 including theory commands '(co)inductive', '(co)datatype',
  5665 'rep_datatype', 'inductive_cases', as well as methods 'ind_cases',
  5666 'induct_tac', 'case_tac', and 'typecheck' (with attribute 'TC');
  5667 
  5668 * theory Main no longer includes AC; for the Axiom of Choice, base
  5669 your theory on Main_ZFC;
  5670 
  5671 * the integer library now covers quotients and remainders, with many
  5672 laws relating division to addition, multiplication, etc.;
  5673 
  5674 * ZF/UNITY: Chandy and Misra's UNITY is now available in ZF, giving a
  5675 typeless version of the formalism;
  5676 
  5677 * ZF/AC, Coind, IMP, Resid: updated and converted to new-style theory
  5678 format;
  5679 
  5680 * ZF/Induct: new directory for examples of inductive definitions,
  5681 including theory Multiset for multiset orderings; converted to
  5682 new-style theory format;
  5683 
  5684 * ZF: many new theorems about lists, ordinals, etc.;
  5685 
  5686 
  5687 *** General ***
  5688 
  5689 * Pure/kernel: meta-level proof terms (by Stefan Berghofer); reference
  5690 variable proof controls level of detail: 0 = no proofs (only oracle
  5691 dependencies), 1 = lemma dependencies, 2 = compact proof terms; see
  5692 also ref manual for further ML interfaces;
  5693 
  5694 * Pure/axclass: removed obsolete ML interface
  5695 goal_subclass/goal_arity;
  5696 
  5697 * Pure/syntax: new token syntax "num" for plain numerals (without "#"
  5698 of "xnum"); potential INCOMPATIBILITY, since -0, -1 etc. are now
  5699 separate tokens, so expressions involving minus need to be spaced
  5700 properly;
  5701 
  5702 * Pure/syntax: support non-oriented infixes, using keyword "infix"
  5703 rather than "infixl" or "infixr";
  5704 
  5705 * Pure/syntax: concrete syntax for dummy type variables admits genuine
  5706 sort constraint specifications in type inference; e.g. "x::_::foo"
  5707 ensures that the type of "x" is of sort "foo" (but not necessarily a
  5708 type variable);
  5709 
  5710 * Pure/syntax: print modes "type_brackets" and "no_type_brackets"
  5711 control output of nested => (types); the default behavior is
  5712 "type_brackets";
  5713 
  5714 * Pure/syntax: builtin parse translation for "_constify" turns valued
  5715 tokens into AST constants;
  5716 
  5717 * Pure/syntax: prefer later declarations of translations and print
  5718 translation functions; potential INCOMPATIBILITY: need to reverse
  5719 multiple declarations for same syntax element constant;
  5720 
  5721 * Pure/show_hyps reset by default (in accordance to existing Isar
  5722 practice);
  5723 
  5724 * Provers/classical: renamed addaltern to addafter, addSaltern to
  5725 addSafter;
  5726 
  5727 * Provers/clasimp: ``iff'' declarations now handle conditional rules
  5728 as well;
  5729 
  5730 * system: tested support for MacOS X; should be able to get Isabelle +
  5731 Proof General to work in a plain Terminal after installing Poly/ML
  5732 (e.g. from the Isabelle distribution area) and GNU bash alone
  5733 (e.g. from http://www.apple.com); full X11, XEmacs and X-Symbol
  5734 support requires further installations, e.g. from
  5735 http://fink.sourceforge.net/);
  5736 
  5737 * system: support Poly/ML 4.1.1 (able to manage larger heaps);
  5738 
  5739 * system: reduced base memory usage by Poly/ML (approx. 20 MB instead
  5740 of 40 MB), cf. ML_OPTIONS;
  5741 
  5742 * system: Proof General keywords specification is now part of the
  5743 Isabelle distribution (see etc/isar-keywords.el);
  5744 
  5745 * system: support for persistent Proof General sessions (refrain from
  5746 outdating all loaded theories on startup); user may create writable
  5747 logic images like this: ``isabelle -q HOL Test'';
  5748 
  5749 * system: smart selection of Isabelle process versus Isabelle
  5750 interface, accommodates case-insensitive file systems (e.g. HFS+); may
  5751 run both "isabelle" and "Isabelle" even if file names are badly
  5752 damaged (executable inspects the case of the first letter of its own
  5753 name); added separate "isabelle-process" and "isabelle-interface";
  5754 
  5755 * system: refrain from any attempt at filtering input streams; no
  5756 longer support ``8bit'' encoding of old isabelle font, instead proper
  5757 iso-latin characters may now be used; the related isatools
  5758 "symbolinput" and "nonascii" have disappeared as well;
  5759 
  5760 * system: removed old "xterm" interface (the print modes "xterm" and
  5761 "xterm_color" are still available for direct use in a suitable
  5762 terminal);
  5763 
  5764 
  5765 
  5766 New in Isabelle99-2 (February 2001)
  5767 -----------------------------------
  5768 
  5769 *** Overview of INCOMPATIBILITIES ***
  5770 
  5771 * HOL: please note that theories in the Library and elsewhere often use the
  5772 new-style (Isar) format; to refer to their theorems in an ML script you must
  5773 bind them to ML identifers by e.g.      val thm_name = thm "thm_name";
  5774 
  5775 * HOL: inductive package no longer splits induction rule aggressively,
  5776 but only as far as specified by the introductions given; the old
  5777 format may be recovered via ML function complete_split_rule or attribute
  5778 'split_rule (complete)';
  5779 
  5780 * HOL: induct renamed to lfp_induct, lfp_Tarski to lfp_unfold,
  5781 gfp_Tarski to gfp_unfold;
  5782 
  5783 * HOL: contrapos, contrapos2 renamed to contrapos_nn, contrapos_pp;
  5784 
  5785 * HOL: infix "dvd" now has priority 50 rather than 70 (because it is a
  5786 relation); infix "^^" has been renamed "``"; infix "``" has been
  5787 renamed "`"; "univalent" has been renamed "single_valued";
  5788 
  5789 * HOL/Real: "rinv" and "hrinv" replaced by overloaded "inverse"
  5790 operation;
  5791 
  5792 * HOLCF: infix "`" has been renamed "$"; the symbol syntax is \<cdot>;
  5793 
  5794 * Isar: 'obtain' no longer declares "that" fact as simp/intro;
  5795 
  5796 * Isar/HOL: method 'induct' now handles non-atomic goals; as a
  5797 consequence, it is no longer monotonic wrt. the local goal context
  5798 (which is now passed through the inductive cases);
  5799 
  5800 * Document preparation: renamed standard symbols \<ll> to \<lless> and
  5801 \<gg> to \<ggreater>;
  5802 
  5803 
  5804 *** Document preparation ***
  5805 
  5806 * \isabellestyle{NAME} selects version of Isabelle output (currently
  5807 available: are "it" for near math-mode best-style output, "sl" for
  5808 slanted text style, and "tt" for plain type-writer; if no
  5809 \isabellestyle command is given, output is according to slanted
  5810 type-writer);
  5811 
  5812 * support sub/super scripts (for single symbols only), input syntax is
  5813 like this: "A\<^sup>*" or "A\<^sup>\<star>";
  5814 
  5815 * some more standard symbols; see Appendix A of the system manual for
  5816 the complete list of symbols defined in isabellesym.sty;
  5817 
  5818 * improved isabelle style files; more abstract symbol implementation
  5819 (should now use \isamath{...} and \isatext{...} in custom symbol
  5820 definitions);
  5821 
  5822 * antiquotation @{goals} and @{subgoals} for output of *dynamic* goals
  5823 state; Note that presentation of goal states does not conform to
  5824 actual human-readable proof documents.  Please do not include goal
  5825 states into document output unless you really know what you are doing!
  5826 
  5827 * proper indentation of antiquoted output with proportional LaTeX
  5828 fonts;
  5829 
  5830 * no_document ML operator temporarily disables LaTeX document
  5831 generation;
  5832 
  5833 * isatool unsymbolize tunes sources for plain ASCII communication;
  5834 
  5835 
  5836 *** Isar ***
  5837 
  5838 * Pure: Isar now suffers initial goal statements to contain unbound
  5839 schematic variables (this does not conform to actual readable proof
  5840 documents, due to unpredictable outcome and non-compositional proof
  5841 checking); users who know what they are doing may use schematic goals
  5842 for Prolog-style synthesis of proven results;
  5843 
  5844 * Pure: assumption method (an implicit finishing) now handles actual
  5845 rules as well;
  5846 
  5847 * Pure: improved 'obtain' --- moved to Pure, insert "that" into
  5848 initial goal, declare "that" only as Pure intro (only for single
  5849 steps); the "that" rule assumption may now be involved in implicit
  5850 finishing, thus ".." becomes a feasible for trivial obtains;
  5851 
  5852 * Pure: default proof step now includes 'intro_classes'; thus trivial
  5853 instance proofs may be performed by "..";
  5854 
  5855 * Pure: ?thesis / ?this / "..." now work for pure meta-level
  5856 statements as well;
  5857 
  5858 * Pure: more robust selection of calculational rules;
  5859 
  5860 * Pure: the builtin notion of 'finished' goal now includes the ==-refl
  5861 rule (as well as the assumption rule);
  5862 
  5863 * Pure: 'thm_deps' command visualizes dependencies of theorems and
  5864 lemmas, using the graph browser tool;
  5865 
  5866 * Pure: predict failure of "show" in interactive mode;
  5867 
  5868 * Pure: 'thms_containing' now takes actual terms as arguments;
  5869 
  5870 * HOL: improved method 'induct' --- now handles non-atomic goals
  5871 (potential INCOMPATIBILITY); tuned error handling;
  5872 
  5873 * HOL: cases and induct rules now provide explicit hints about the
  5874 number of facts to be consumed (0 for "type" and 1 for "set" rules);
  5875 any remaining facts are inserted into the goal verbatim;
  5876 
  5877 * HOL: local contexts (aka cases) may now contain term bindings as
  5878 well; the 'cases' and 'induct' methods new provide a ?case binding for
  5879 the result to be shown in each case;
  5880 
  5881 * HOL: added 'recdef_tc' command;
  5882 
  5883 * isatool convert assists in eliminating legacy ML scripts;
  5884 
  5885 
  5886 *** HOL ***
  5887 
  5888 * HOL/Library: a collection of generic theories to be used together
  5889 with main HOL; the theory loader path already includes this directory
  5890 by default; the following existing theories have been moved here:
  5891 HOL/Induct/Multiset, HOL/Induct/Acc (as Accessible_Part), HOL/While
  5892 (as While_Combinator), HOL/Lex/Prefix (as List_Prefix);
  5893 
  5894 * HOL/Unix: "Some aspects of Unix file-system security", a typical
  5895 modelling and verification task performed in Isabelle/HOL +
  5896 Isabelle/Isar + Isabelle document preparation (by Markus Wenzel).
  5897 
  5898 * HOL/Algebra: special summation operator SUM no longer exists, it has
  5899 been replaced by setsum; infix 'assoc' now has priority 50 (like
  5900 'dvd'); axiom 'one_not_zero' has been moved from axclass 'ring' to
  5901 'domain', this makes the theory consistent with mathematical
  5902 literature;
  5903 
  5904 * HOL basics: added overloaded operations "inverse" and "divide"
  5905 (infix "/"), syntax for generic "abs" operation, generic summation
  5906 operator \<Sum>;
  5907 
  5908 * HOL/typedef: simplified package, provide more useful rules (see also
  5909 HOL/subset.thy);
  5910 
  5911 * HOL/datatype: induction rule for arbitrarily branching datatypes is
  5912 now expressed as a proper nested rule (old-style tactic scripts may
  5913 require atomize_strip_tac to cope with non-atomic premises);
  5914 
  5915 * HOL: renamed theory "Prod" to "Product_Type", renamed "split" rule
  5916 to "split_conv" (old name still available for compatibility);
  5917 
  5918 * HOL: improved concrete syntax for strings (e.g. allows translation
  5919 rules with string literals);
  5920 
  5921 * HOL-Real-Hyperreal: this extends HOL-Real with the hyperreals
  5922  and Fleuriot's mechanization of analysis, including the transcendental
  5923  functions for the reals;
  5924 
  5925 * HOL/Real, HOL/Hyperreal: improved arithmetic simplification;
  5926 
  5927 
  5928 *** CTT ***
  5929 
  5930 * CTT: x-symbol support for Pi, Sigma, -->, : (membership); note that
  5931 "lam" is displayed as TWO lambda-symbols
  5932 
  5933 * CTT: theory Main now available, containing everything (that is, Bool
  5934 and Arith);
  5935 
  5936 
  5937 *** General ***
  5938 
  5939 * Pure: the Simplifier has been implemented properly as a derived rule
  5940 outside of the actual kernel (at last!); the overall performance
  5941 penalty in practical applications is about 50%, while reliability of
  5942 the Isabelle inference kernel has been greatly improved;
  5943 
  5944 * print modes "brackets" and "no_brackets" control output of nested =>
  5945 (types) and ==> (props); the default behaviour is "brackets";
  5946 
  5947 * Provers: fast_tac (and friends) now handle actual object-logic rules
  5948 as assumptions as well;
  5949 
  5950 * system: support Poly/ML 4.0;
  5951 
  5952 * system: isatool install handles KDE version 1 or 2;
  5953 
  5954 
  5955 
  5956 New in Isabelle99-1 (October 2000)
  5957 ----------------------------------
  5958 
  5959 *** Overview of INCOMPATIBILITIES ***
  5960 
  5961 * HOL: simplification of natural numbers is much changed; to partly
  5962 recover the old behaviour (e.g. to prevent n+n rewriting to #2*n)
  5963 issue the following ML commands:
  5964 
  5965   Delsimprocs Nat_Numeral_Simprocs.cancel_numerals;
  5966   Delsimprocs [Nat_Numeral_Simprocs.combine_numerals];
  5967 
  5968 * HOL: simplification no longer dives into case-expressions; this is
  5969 controlled by "t.weak_case_cong" for each datatype t;
  5970 
  5971 * HOL: nat_less_induct renamed to less_induct;
  5972 
  5973 * HOL: systematic renaming of the SOME (Eps) rules, may use isatool
  5974 fixsome to patch .thy and .ML sources automatically;
  5975 
  5976   select_equality  -> some_equality
  5977   select_eq_Ex     -> some_eq_ex
  5978   selectI2EX       -> someI2_ex
  5979   selectI2         -> someI2
  5980   selectI          -> someI
  5981   select1_equality -> some1_equality
  5982   Eps_sym_eq       -> some_sym_eq_trivial
  5983   Eps_eq           -> some_eq_trivial
  5984 
  5985 * HOL: exhaust_tac on datatypes superceded by new generic case_tac;
  5986 
  5987 * HOL: removed obsolete theorem binding expand_if (refer to split_if
  5988 instead);
  5989 
  5990 * HOL: the recursion equations generated by 'recdef' are now called
  5991 f.simps instead of f.rules;
  5992 
  5993 * HOL: qed_spec_mp now also handles bounded ALL as well;
  5994 
  5995 * HOL: 0 is now overloaded, so the type constraint ":: nat" may
  5996 sometimes be needed;
  5997 
  5998 * HOL: the constant for "f``x" is now "image" rather than "op ``";
  5999 
  6000 * HOL: the constant for "f-``x" is now "vimage" rather than "op -``";
  6001 
  6002 * HOL: the disjoint sum is now "<+>" instead of "Plus"; the cartesian
  6003 product is now "<*>" instead of "Times"; the lexicographic product is
  6004 now "<*lex*>" instead of "**";
  6005 
  6006 * HOL: theory Sexp is now in HOL/Induct examples (it used to be part
  6007 of main HOL, but was unused); better use HOL's datatype package;
  6008 
  6009 * HOL: removed "symbols" syntax for constant "override" of theory Map;
  6010 the old syntax may be recovered as follows:
  6011 
  6012   syntax (symbols)
  6013     override  :: "('a ~=> 'b) => ('a ~=> 'b) => ('a ~=> 'b)"
  6014       (infixl "\\<oplus>" 100)
  6015 
  6016 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  6017 
  6018 * HOL/ML: even fewer consts are declared as global (see theories Ord,
  6019 Lfp, Gfp, WF); this only affects ML packages that refer to const names
  6020 internally;
  6021 
  6022 * HOL and ZF: syntax for quotienting wrt an equivalence relation
  6023 changed from A/r to A//r;
  6024 
  6025 * ZF: new treatment of arithmetic (nat & int) may break some old
  6026 proofs;
  6027 
  6028 * Isar: renamed some attributes (RS -> THEN, simplify -> simplified,
  6029 rulify -> rule_format, elimify -> elim_format, ...);
  6030 
  6031 * Isar/Provers: intro/elim/dest attributes changed; renamed
  6032 intro/intro!/intro!! flags to intro!/intro/intro? (in most cases, one
  6033 should have to change intro!! to intro? only); replaced "delrule" by
  6034 "rule del";
  6035 
  6036 * Isar/HOL: renamed "intrs" to "intros" in inductive definitions;
  6037 
  6038 * Provers: strengthened force_tac by using new first_best_tac;
  6039 
  6040 * LaTeX document preparation: several changes of isabelle.sty (see
  6041 lib/texinputs);
  6042 
  6043 
  6044 *** Document preparation ***
  6045 
  6046 * formal comments (text blocks etc.) in new-style theories may now
  6047 contain antiquotations of thm/prop/term/typ/text to be presented
  6048 according to latex print mode; concrete syntax is like this:
  6049 @{term[show_types] "f(x) = a + x"};
  6050 
  6051 * isatool mkdir provides easy setup of Isabelle session directories,
  6052 including proper document sources;
  6053 
  6054 * generated LaTeX sources are now deleted after successful run
  6055 (isatool document -c); may retain a copy somewhere else via -D option
  6056 of isatool usedir;
  6057 
  6058 * isatool usedir -D now lets isatool latex -o sty update the Isabelle
  6059 style files, achieving self-contained LaTeX sources and simplifying
  6060 LaTeX debugging;
  6061 
  6062 * old-style theories now produce (crude) LaTeX output as well;
  6063 
  6064 * browser info session directories are now self-contained (may be put
  6065 on WWW server seperately); improved graphs of nested sessions; removed
  6066 graph for 'all sessions';
  6067 
  6068 * several improvements in isabelle style files; \isabellestyle{it}
  6069 produces fake math mode output; \isamarkupheader is now \section by
  6070 default; see lib/texinputs/isabelle.sty etc.;
  6071 
  6072 
  6073 *** Isar ***
  6074 
  6075 * Isar/Pure: local results and corresponding term bindings are now
  6076 subject to Hindley-Milner polymorphism (similar to ML); this
  6077 accommodates incremental type-inference very nicely;
  6078 
  6079 * Isar/Pure: new derived language element 'obtain' supports
  6080 generalized existence reasoning;
  6081 
  6082 * Isar/Pure: new calculational elements 'moreover' and 'ultimately'
  6083 support accumulation of results, without applying any rules yet;
  6084 useful to collect intermediate results without explicit name
  6085 references, and for use with transitivity rules with more than 2
  6086 premises;
  6087 
  6088 * Isar/Pure: scalable support for case-analysis type proofs: new
  6089 'case' language element refers to local contexts symbolically, as
  6090 produced by certain proof methods; internally, case names are attached
  6091 to theorems as "tags";
  6092 
  6093 * Isar/Pure: theory command 'hide' removes declarations from
  6094 class/type/const name spaces;
  6095 
  6096 * Isar/Pure: theory command 'defs' supports option "(overloaded)" to
  6097 indicate potential overloading;
  6098 
  6099 * Isar/Pure: changed syntax of local blocks from {{ }} to { };
  6100 
  6101 * Isar/Pure: syntax of sorts made 'inner', i.e. have to write
  6102 "{a,b,c}" instead of {a,b,c};
  6103 
  6104 * Isar/Pure now provides its own version of intro/elim/dest
  6105 attributes; useful for building new logics, but beware of confusion
  6106 with the version in Provers/classical;
  6107 
  6108 * Isar/Pure: the local context of (non-atomic) goals is provided via
  6109 case name 'antecedent';
  6110 
  6111 * Isar/Pure: removed obsolete 'transfer' attribute (transfer of thms
  6112 to the current context is now done automatically);
  6113 
  6114 * Isar/Pure: theory command 'method_setup' provides a simple interface
  6115 for definining proof methods in ML;
  6116 
  6117 * Isar/Provers: intro/elim/dest attributes changed; renamed
  6118 intro/intro!/intro!! flags to intro!/intro/intro? (INCOMPATIBILITY, in
  6119 most cases, one should have to change intro!! to intro? only);
  6120 replaced "delrule" by "rule del";
  6121 
  6122 * Isar/Provers: new 'hypsubst' method, plain 'subst' method and
  6123 'symmetric' attribute (the latter supercedes [RS sym]);
  6124 
  6125 * Isar/Provers: splitter support (via 'split' attribute and 'simp'
  6126 method modifier); 'simp' method: 'only:' modifier removes loopers as
  6127 well (including splits);
  6128 
  6129 * Isar/Provers: Simplifier and Classical methods now support all kind
  6130 of modifiers used in the past, including 'cong', 'iff', etc.
  6131 
  6132 * Isar/Provers: added 'fastsimp' and 'clarsimp' methods (combination
  6133 of Simplifier and Classical reasoner);
  6134 
  6135 * Isar/HOL: new proof method 'cases' and improved version of 'induct'
  6136 now support named cases; major packages (inductive, datatype, primrec,
  6137 recdef) support case names and properly name parameters;
  6138 
  6139 * Isar/HOL: new transitivity rules for substitution in inequalities --
  6140 monotonicity conditions are extracted to be proven at end of
  6141 calculations;
  6142 
  6143 * Isar/HOL: removed 'case_split' thm binding, should use 'cases' proof
  6144 method anyway;
  6145 
  6146 * Isar/HOL: removed old expand_if = split_if; theorems if_splits =
  6147 split_if split_if_asm; datatype package provides theorems foo.splits =
  6148 foo.split foo.split_asm for each datatype;
  6149 
  6150 * Isar/HOL: tuned inductive package, rename "intrs" to "intros"
  6151 (potential INCOMPATIBILITY), emulation of mk_cases feature for proof
  6152 scripts: new 'inductive_cases' command and 'ind_cases' method; (Note:
  6153 use "(cases (simplified))" method in proper proof texts);
  6154 
  6155 * Isar/HOL: added global 'arith_split' attribute for 'arith' method;
  6156 
  6157 * Isar: names of theorems etc. may be natural numbers as well;
  6158 
  6159 * Isar: 'pr' command: optional arguments for goals_limit and
  6160 ProofContext.prems_limit; no longer prints theory contexts, but only
  6161 proof states;
  6162 
  6163 * Isar: diagnostic commands 'pr', 'thm', 'prop', 'term', 'typ' admit
  6164 additional print modes to be specified; e.g. "pr(latex)" will print
  6165 proof state according to the Isabelle LaTeX style;
  6166 
  6167 * Isar: improved support for emulating tactic scripts, including proof
  6168 methods 'rule_tac' etc., 'cut_tac', 'thin_tac', 'subgoal_tac',
  6169 'rename_tac', 'rotate_tac', 'tactic', and 'case_tac' / 'induct_tac'
  6170 (for HOL datatypes);
  6171 
  6172 * Isar: simplified (more robust) goal selection of proof methods: 1st
  6173 goal, all goals, or explicit goal specifier (tactic emulation); thus
  6174 'proof method scripts' have to be in depth-first order;
  6175 
  6176 * Isar: tuned 'let' syntax: replaced 'as' keyword by 'and';
  6177 
  6178 * Isar: removed 'help' command, which hasn't been too helpful anyway;
  6179 should instead use individual commands for printing items
  6180 (print_commands, print_methods etc.);
  6181 
  6182 * Isar: added 'nothing' --- the empty list of theorems;
  6183 
  6184 
  6185 *** HOL ***
  6186 
  6187 * HOL/MicroJava: formalization of a fragment of Java, together with a
  6188 corresponding virtual machine and a specification of its bytecode
  6189 verifier and a lightweight bytecode verifier, including proofs of
  6190 type-safety; by Gerwin Klein, Tobias Nipkow, David von Oheimb, and
  6191 Cornelia Pusch (see also the homepage of project Bali at
  6192 http://isabelle.in.tum.de/Bali/);
  6193 
  6194 * HOL/Algebra: new theory of rings and univariate polynomials, by
  6195 Clemens Ballarin;
  6196 
  6197 * HOL/NumberTheory: fundamental Theorem of Arithmetic, Chinese
  6198 Remainder Theorem, Fermat/Euler Theorem, Wilson's Theorem, by Thomas M
  6199 Rasmussen;
  6200 
  6201 * HOL/Lattice: fundamental concepts of lattice theory and order
  6202 structures, including duals, properties of bounds versus algebraic
  6203 laws, lattice operations versus set-theoretic ones, the Knaster-Tarski
  6204 Theorem for complete lattices etc.; may also serve as a demonstration
  6205 for abstract algebraic reasoning using axiomatic type classes, and
  6206 mathematics-style proof in Isabelle/Isar; by Markus Wenzel;
  6207 
  6208 * HOL/Prolog: a (bare-bones) implementation of Lambda-Prolog, by David
  6209 von Oheimb;
  6210 
  6211 * HOL/IMPP: extension of IMP with local variables and mutually
  6212 recursive procedures, by David von Oheimb;
  6213 
  6214 * HOL/Lambda: converted into new-style theory and document;
  6215 
  6216 * HOL/ex/Multiquote: example of multiple nested quotations and
  6217 anti-quotations -- basically a generalized version of de-Bruijn
  6218 representation; very useful in avoiding lifting of operations;
  6219 
  6220 * HOL/record: added general record equality rule to simpset; fixed
  6221 select-update simplification procedure to handle extended records as
  6222 well; admit "r" as field name;
  6223 
  6224 * HOL: 0 is now overloaded over the new sort "zero", allowing its use with
  6225 other numeric types and also as the identity of groups, rings, etc.;
  6226 
  6227 * HOL: new axclass plus_ac0 for addition with the AC-laws and 0 as identity.
  6228 Types nat and int belong to this axclass;
  6229 
  6230 * HOL: greatly improved simplification involving numerals of type nat, int, real:
  6231    (i + #8 + j) = Suc k simplifies to  #7 + (i + j) = k
  6232    i*j + k + j*#3*i     simplifies to  #4*(i*j) + k
  6233   two terms #m*u and #n*u are replaced by #(m+n)*u
  6234     (where #m, #n and u can implicitly be 1; this is simproc combine_numerals)
  6235   and the term/formula #m*u+x ~~ #n*u+y simplifies simplifies to #(m-n)+x ~~ y