NEWS
author haftmann
Fri Aug 20 17:48:30 2010 +0200 (2010-08-20)
changeset 38622 86fc906dcd86
parent 38559 befdd6833ec0
child 38642 8fa437809c67
permissions -rw-r--r--
split and enriched theory SetsAndFunctions
     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 
    27 *** Pure ***
    28 
    29 * Interpretation command 'interpret' accepts a list of equations like
    30 'interpretation' does.
    31 
    32 * Diagnostic command 'print_interps' prints interpretations in proofs
    33 in addition to interpretations in theories.
    34 
    35 
    36 *** HOL ***
    37 
    38 * Theory SetsAndFunctions has been split into Function_Algebras and Set_Algebras;
    39 canonical names for instance definitions for functions; various improvements.
    40 INCOMPATIBILITY.
    41 
    42 * Records: logical foundation type for records do not carry a '_type' suffix
    43 any longer.  INCOMPATIBILITY.
    44 
    45 * Code generation for records: more idiomatic representation of record types.
    46 Warning: records are not covered by ancient SML code generation any longer.
    47 INCOMPATIBILITY.  In cases of need, a suitable rep_datatype declaration
    48 helps to succeed then:
    49 
    50   record 'a foo = ...
    51   ...
    52   rep_datatype foo_ext ...
    53 
    54 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
    55 INCOMPATIBILITY.
    56 
    57 * Quickcheck in locales considers interpretations of that locale for
    58 counter example search.
    59 
    60 * Theory Library/Monad_Syntax provides do-syntax for monad types.  Syntax
    61 in Library/State_Monad has been changed to avoid ambiguities.
    62 INCOMPATIBILITY.
    63 
    64 * Code generator: export_code without explicit file declaration prints
    65 to standard output.  INCOMPATIBILITY.
    66 
    67 * Abolished symbol type names:  "prod" and "sum" replace "*" and "+"
    68 respectively.  INCOMPATIBILITY.
    69 
    70 * Constant "split" has been merged with constant "prod_case";  names
    71 of ML functions, facts etc. involving split have been retained so far,
    72 though.  INCOMPATIBILITY.
    73 
    74 * Dropped old infix syntax "mem" for List.member;  use "in set"
    75 instead.  INCOMPATIBILITY.
    76 
    77 * Refactoring of code-generation specific operations in List.thy
    78 
    79   constants
    80     null ~> List.null
    81 
    82   facts
    83     mem_iff ~> member_def
    84     null_empty ~> null_def
    85 
    86 INCOMPATIBILITY.  Note that these were not suppossed to be used
    87 regularly unless for striking reasons;  their main purpose was code
    88 generation.
    89 
    90 * Some previously unqualified names have been qualified:
    91 
    92   types
    93     bool ~> HOL.bool
    94     nat ~> Nat.nat
    95 
    96   constants
    97     Trueprop ~> HOL.Trueprop
    98     True ~> HOL.True
    99     False ~> HOL.False
   100     Not ~> HOL.Not
   101     The ~> HOL.The
   102     All ~> HOL.All
   103     Ex ~> HOL.Ex
   104     Ex1 ~> HOL.Ex1
   105     Let ~> HOL.Let
   106     If ~> HOL.If
   107     Ball ~> Set.Ball
   108     Bex ~> Set.Bex
   109     Suc ~> Nat.Suc
   110     Pair ~> Product_Type.Pair
   111     fst ~> Product_Type.fst
   112     snd ~> Product_Type.snd
   113     curry ~> Product_Type.curry
   114     op : ~> Set.member
   115     Collect ~> Set.Collect
   116 
   117 INCOMPATIBILITY.
   118 
   119 * Removed simplifier congruence rule of "prod_case", as has for long
   120 been the case with "split".  INCOMPATIBILITY.
   121 
   122 * Datatype package: theorems generated for executable equality
   123 (class eq) carry proper names and are treated as default code
   124 equations.
   125 
   126 * List.thy: use various operations from the Haskell prelude when
   127 generating Haskell code.
   128 
   129 * code_simp.ML and method code_simp: simplification with rules determined
   130 by code generator.
   131 
   132 * code generator: do not print function definitions for case
   133 combinators any longer.
   134 
   135 * Multivariate Analysis: Introduced a type class for euclidean space. Most
   136 theorems are now stated in terms of euclidean spaces instead of finite
   137 cartesian products.
   138 
   139   types
   140     real ^ 'n ~>  'a::real_vector
   141               ~>  'a::euclidean_space
   142               ~>  'a::ordered_euclidean_space
   143         (depends on your needs)
   144 
   145   constants
   146      _ $ _        ~> _ $$ _
   147      \<chi> x. _  ~> \<chi>\<chi> x. _
   148      CARD('n)     ~> DIM('a)
   149 
   150 Also note that the indices are now natural numbers and not from some finite
   151 type. Finite cartesian products of euclidean spaces, products of euclidean
   152 spaces the real and complex numbers are instantiated to be euclidean_spaces.
   153 
   154 INCOMPATIBILITY.
   155 
   156 * Inductive package: offers new command "inductive_simps" to automatically
   157 derive instantiated and simplified equations for inductive predicates,
   158 similar to inductive_cases.
   159 
   160 
   161 *** FOL ***
   162 
   163 * All constant names are now qualified.  INCOMPATIBILITY.
   164 
   165 
   166 *** ZF ***
   167 
   168 * All constant names are now qualified.  INCOMPATIBILITY.
   169 
   170 
   171 *** ML ***
   172 
   173 * ML antiquotations @{theory} and @{theory_ref} refer to named
   174 theories from the ancestry of the current context, not any accidental
   175 theory loader state as before.  Potential INCOMPATIBILITY, subtle
   176 change in semantics.
   177 
   178 
   179 *** System ***
   180 
   181 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   182 
   183 
   184 
   185 New in Isabelle2009-2 (June 2010)
   186 ---------------------------------
   187 
   188 *** General ***
   189 
   190 * Authentic syntax for *all* logical entities (type classes, type
   191 constructors, term constants): provides simple and robust
   192 correspondence between formal entities and concrete syntax.  Within
   193 the parse tree / AST representations, "constants" are decorated by
   194 their category (class, type, const) and spelled out explicitly with
   195 their full internal name.
   196 
   197 Substantial INCOMPATIBILITY concerning low-level syntax declarations
   198 and translations (translation rules and translation functions in ML).
   199 Some hints on upgrading:
   200 
   201   - Many existing uses of 'syntax' and 'translations' can be replaced
   202     by more modern 'type_notation', 'notation' and 'abbreviation',
   203     which are independent of this issue.
   204 
   205   - 'translations' require markup within the AST; the term syntax
   206     provides the following special forms:
   207 
   208       CONST c   -- produces syntax version of constant c from context
   209       XCONST c  -- literally c, checked as constant from context
   210       c         -- literally c, if declared by 'syntax'
   211 
   212     Plain identifiers are treated as AST variables -- occasionally the
   213     system indicates accidental variables via the error "rhs contains
   214     extra variables".
   215 
   216     Type classes and type constructors are marked according to their
   217     concrete syntax.  Some old translations rules need to be written
   218     for the "type" category, using type constructor application
   219     instead of pseudo-term application of the default category
   220     "logic".
   221 
   222   - 'parse_translation' etc. in ML may use the following
   223     antiquotations:
   224 
   225       @{class_syntax c}   -- type class c within parse tree / AST
   226       @{term_syntax c}    -- type constructor c within parse tree / AST
   227       @{const_syntax c}   -- ML version of "CONST c" above
   228       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
   229 
   230   - Literal types within 'typed_print_translations', i.e. those *not*
   231     represented as pseudo-terms are represented verbatim.  Use @{class
   232     c} or @{type_name c} here instead of the above syntax
   233     antiquotations.
   234 
   235 Note that old non-authentic syntax was based on unqualified base
   236 names, so all of the above "constant" names would coincide.  Recall
   237 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
   238 diagnose syntax problems.
   239 
   240 * Type constructors admit general mixfix syntax, not just infix.
   241 
   242 * Concrete syntax may be attached to local entities without a proof
   243 body, too.  This works via regular mixfix annotations for 'fix',
   244 'def', 'obtain' etc. or via the explicit 'write' command, which is
   245 similar to the 'notation' command in theory specifications.
   246 
   247 * Discontinued unnamed infix syntax (legacy feature for many years) --
   248 need to specify constant name and syntax separately.  Internal ML
   249 datatype constructors have been renamed from InfixName to Infix etc.
   250 Minor INCOMPATIBILITY.
   251 
   252 * Schematic theorem statements need to be explicitly markup as such,
   253 via commands 'schematic_lemma', 'schematic_theorem',
   254 'schematic_corollary'.  Thus the relevance of the proof is made
   255 syntactically clear, which impacts performance in a parallel or
   256 asynchronous interactive environment.  Minor INCOMPATIBILITY.
   257 
   258 * Use of cumulative prems via "!" in some proof methods has been
   259 discontinued (old legacy feature).
   260 
   261 * References 'trace_simp' and 'debug_simp' have been replaced by
   262 configuration options stored in the context. Enabling tracing (the
   263 case of debugging is similar) in proofs works via
   264 
   265   using [[trace_simp = true]]
   266 
   267 Tracing is then active for all invocations of the simplifier in
   268 subsequent goal refinement steps. Tracing may also still be enabled or
   269 disabled via the ProofGeneral settings menu.
   270 
   271 * Separate commands 'hide_class', 'hide_type', 'hide_const',
   272 'hide_fact' replace the former 'hide' KIND command.  Minor
   273 INCOMPATIBILITY.
   274 
   275 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
   276 more efficient than combinations with -q1 or -q2.
   277 
   278 
   279 *** Pure ***
   280 
   281 * Proofterms record type-class reasoning explicitly, using the
   282 "unconstrain" operation internally.  This eliminates all sort
   283 constraints from a theorem and proof, introducing explicit
   284 OFCLASS-premises.  On the proof term level, this operation is
   285 automatically applied at theorem boundaries, such that closed proofs
   286 are always free of sort constraints.  INCOMPATIBILITY for tools that
   287 inspect proof terms.
   288 
   289 * Local theory specifications may depend on extra type variables that
   290 are not present in the result type -- arguments TYPE('a) :: 'a itself
   291 are added internally.  For example:
   292 
   293   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
   294 
   295 * Predicates of locales introduced by classes carry a mandatory
   296 "class" prefix.  INCOMPATIBILITY.
   297 
   298 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
   299 
   300 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
   301 'class' instead.
   302 
   303 * Command 'code_reflect' allows to incorporate generated ML code into
   304 runtime environment; replaces immature code_datatype antiquotation.
   305 INCOMPATIBILITY.
   306 
   307 * Code generator: simple concept for abstract datatypes obeying
   308 invariants.
   309 
   310 * Code generator: details of internal data cache have no impact on the
   311 user space functionality any longer.
   312 
   313 * Methods "unfold_locales" and "intro_locales" ignore non-locale
   314 subgoals.  This is more appropriate for interpretations with 'where'.
   315 INCOMPATIBILITY.
   316 
   317 * Command 'example_proof' opens an empty proof body.  This allows to
   318 experiment with Isar, without producing any persistent result.
   319 
   320 * Commands 'type_notation' and 'no_type_notation' declare type syntax
   321 within a local theory context, with explicit checking of the
   322 constructors involved (in contrast to the raw 'syntax' versions).
   323 
   324 * Commands 'types' and 'typedecl' now work within a local theory
   325 context -- without introducing dependencies on parameters or
   326 assumptions, which is not possible in Isabelle/Pure.
   327 
   328 * Command 'defaultsort' has been renamed to 'default_sort', it works
   329 within a local theory context.  Minor INCOMPATIBILITY.
   330 
   331 
   332 *** HOL ***
   333 
   334 * Command 'typedef' now works within a local theory context -- without
   335 introducing dependencies on parameters or assumptions, which is not
   336 possible in Isabelle/Pure/HOL.  Note that the logical environment may
   337 contain multiple interpretations of local typedefs (with different
   338 non-emptiness proofs), even in a global theory context.
   339 
   340 * New package for quotient types.  Commands 'quotient_type' and
   341 'quotient_definition' may be used for defining types and constants by
   342 quotient constructions.  An example is the type of integers created by
   343 quotienting pairs of natural numbers:
   344 
   345   fun
   346     intrel :: "(nat * nat) => (nat * nat) => bool"
   347   where
   348     "intrel (x, y) (u, v) = (x + v = u + y)"
   349 
   350   quotient_type int = "nat * nat" / intrel
   351     by (auto simp add: equivp_def expand_fun_eq)
   352 
   353   quotient_definition
   354     "0::int" is "(0::nat, 0::nat)"
   355 
   356 The method "lifting" can be used to lift of theorems from the
   357 underlying "raw" type to the quotient type.  The example
   358 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
   359 construction and provides a reasoning infrastructure for finite sets.
   360 
   361 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
   362 clash with new theory Quotient in Main HOL.
   363 
   364 * Moved the SMT binding into the main HOL session, eliminating
   365 separate HOL-SMT session.
   366 
   367 * List membership infix mem operation is only an input abbreviation.
   368 INCOMPATIBILITY.
   369 
   370 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
   371 for future developements; former Library/Word.thy is still present in
   372 the AFP entry RSAPPS.
   373 
   374 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
   375 longer shadowed.  INCOMPATIBILITY.
   376 
   377 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
   378 INCOMPATIBILITY.
   379 
   380 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
   381 INCOMPATIBILITY.
   382 
   383 * Dropped normalizing_semiring etc; use the facts in semiring classes
   384 instead.  INCOMPATIBILITY.
   385 
   386 * Dropped several real-specific versions of lemmas about floor and
   387 ceiling; use the generic lemmas from theory "Archimedean_Field"
   388 instead.  INCOMPATIBILITY.
   389 
   390   floor_number_of_eq         ~> floor_number_of
   391   le_floor_eq_number_of      ~> number_of_le_floor
   392   le_floor_eq_zero           ~> zero_le_floor
   393   le_floor_eq_one            ~> one_le_floor
   394   floor_less_eq_number_of    ~> floor_less_number_of
   395   floor_less_eq_zero         ~> floor_less_zero
   396   floor_less_eq_one          ~> floor_less_one
   397   less_floor_eq_number_of    ~> number_of_less_floor
   398   less_floor_eq_zero         ~> zero_less_floor
   399   less_floor_eq_one          ~> one_less_floor
   400   floor_le_eq_number_of      ~> floor_le_number_of
   401   floor_le_eq_zero           ~> floor_le_zero
   402   floor_le_eq_one            ~> floor_le_one
   403   floor_subtract_number_of   ~> floor_diff_number_of
   404   floor_subtract_one         ~> floor_diff_one
   405   ceiling_number_of_eq       ~> ceiling_number_of
   406   ceiling_le_eq_number_of    ~> ceiling_le_number_of
   407   ceiling_le_zero_eq         ~> ceiling_le_zero
   408   ceiling_le_eq_one          ~> ceiling_le_one
   409   less_ceiling_eq_number_of  ~> number_of_less_ceiling
   410   less_ceiling_eq_zero       ~> zero_less_ceiling
   411   less_ceiling_eq_one        ~> one_less_ceiling
   412   ceiling_less_eq_number_of  ~> ceiling_less_number_of
   413   ceiling_less_eq_zero       ~> ceiling_less_zero
   414   ceiling_less_eq_one        ~> ceiling_less_one
   415   le_ceiling_eq_number_of    ~> number_of_le_ceiling
   416   le_ceiling_eq_zero         ~> zero_le_ceiling
   417   le_ceiling_eq_one          ~> one_le_ceiling
   418   ceiling_subtract_number_of ~> ceiling_diff_number_of
   419   ceiling_subtract_one       ~> ceiling_diff_one
   420 
   421 * Theory "Finite_Set": various folding_XXX locales facilitate the
   422 application of the various fold combinators on finite sets.
   423 
   424 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
   425 provides abstract red-black tree type which is backed by "RBT_Impl" as
   426 implementation.  INCOMPATIBILTY.
   427 
   428 * Theory Library/Coinductive_List has been removed -- superseded by
   429 AFP/thys/Coinductive.
   430 
   431 * Theory PReal, including the type "preal" and related operations, has
   432 been removed.  INCOMPATIBILITY.
   433 
   434 * Real: new development using Cauchy Sequences.
   435 
   436 * Split off theory "Big_Operators" containing setsum, setprod,
   437 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
   438 
   439 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
   440 "Int" etc.  INCOMPATIBILITY.
   441 
   442 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
   443 
   444 * New set of rules "ac_simps" provides combined assoc / commute
   445 rewrites for all interpretations of the appropriate generic locales.
   446 
   447 * Renamed theory "OrderedGroup" to "Groups" and split theory
   448 "Ring_and_Field" into theories "Rings" and "Fields"; for more
   449 appropriate and more consistent names suitable for name prefixes
   450 within the HOL theories.  INCOMPATIBILITY.
   451 
   452 * Some generic constants have been put to appropriate theories:
   453   - less_eq, less: Orderings
   454   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
   455   - inverse, divide: Rings
   456 INCOMPATIBILITY.
   457 
   458 * More consistent naming of type classes involving orderings (and
   459 lattices):
   460 
   461     lower_semilattice                   ~> semilattice_inf
   462     upper_semilattice                   ~> semilattice_sup
   463 
   464     dense_linear_order                  ~> dense_linorder
   465 
   466     pordered_ab_group_add               ~> ordered_ab_group_add
   467     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
   468     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
   469     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
   470     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
   471     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
   472     pordered_cancel_semiring            ~> ordered_cancel_semiring
   473     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
   474     pordered_comm_ring                  ~> ordered_comm_ring
   475     pordered_comm_semiring              ~> ordered_comm_semiring
   476     pordered_ring                       ~> ordered_ring
   477     pordered_ring_abs                   ~> ordered_ring_abs
   478     pordered_semiring                   ~> ordered_semiring
   479 
   480     ordered_ab_group_add                ~> linordered_ab_group_add
   481     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
   482     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
   483     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
   484     ordered_field                       ~> linordered_field
   485     ordered_field_no_lb                 ~> linordered_field_no_lb
   486     ordered_field_no_ub                 ~> linordered_field_no_ub
   487     ordered_field_dense_linear_order    ~> dense_linordered_field
   488     ordered_idom                        ~> linordered_idom
   489     ordered_ring                        ~> linordered_ring
   490     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
   491     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
   492     ordered_ring_strict                 ~> linordered_ring_strict
   493     ordered_semidom                     ~> linordered_semidom
   494     ordered_semiring                    ~> linordered_semiring
   495     ordered_semiring_1                  ~> linordered_semiring_1
   496     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
   497     ordered_semiring_strict             ~> linordered_semiring_strict
   498 
   499   The following slightly odd type classes have been moved to a
   500   separate theory Library/Lattice_Algebras:
   501 
   502     lordered_ab_group_add               ~> lattice_ab_group_add
   503     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
   504     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
   505     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
   506     lordered_ring                       ~> lattice_ring
   507 
   508 INCOMPATIBILITY.
   509 
   510 * Refined field classes:
   511   - classes division_ring_inverse_zero, field_inverse_zero,
   512     linordered_field_inverse_zero include rule inverse 0 = 0 --
   513     subsumes former division_by_zero class;
   514   - numerous lemmas have been ported from field to division_ring.
   515 INCOMPATIBILITY.
   516 
   517 * Refined algebra theorem collections:
   518   - dropped theorem group group_simps, use algebra_simps instead;
   519   - dropped theorem group ring_simps, use field_simps instead;
   520   - proper theorem collection field_simps subsumes former theorem
   521     groups field_eq_simps and field_simps;
   522   - dropped lemma eq_minus_self_iff which is a duplicate for
   523     equal_neg_zero.
   524 INCOMPATIBILITY.
   525 
   526 * Theory Finite_Set and List: some lemmas have been generalized from
   527 sets to lattices:
   528 
   529   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
   530   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
   531   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
   532   union_Union_fold_union        ~> sup_Sup_fold_sup
   533   Inter_fold_inter              ~> Inf_fold_inf
   534   Union_fold_union              ~> Sup_fold_sup
   535   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
   536   union_UNION_fold_union        ~> sup_SUPR_fold_sup
   537   INTER_fold_inter              ~> INFI_fold_inf
   538   UNION_fold_union              ~> SUPR_fold_sup
   539 
   540 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
   541 replaced by the more convenient lemmas Inf_empty and Sup_empty.
   542 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
   543 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
   544 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
   545 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
   546 
   547 * Reorganized theory Multiset: swapped notation of pointwise and
   548 multiset order:
   549 
   550   - pointwise ordering is instance of class order with standard syntax
   551     <= and <;
   552   - multiset ordering has syntax <=# and <#; partial order properties
   553     are provided by means of interpretation with prefix
   554     multiset_order;
   555   - less duplication, less historical organization of sections,
   556     conversion from associations lists to multisets, rudimentary code
   557     generation;
   558   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
   559     if needed.
   560 
   561 Renamed:
   562 
   563   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
   564   multi_count_ext  ~>  multiset_ext
   565   diff_union_inverse2  ~>  diff_union_cancelR
   566 
   567 INCOMPATIBILITY.
   568 
   569 * Theory Permutation: replaced local "remove" by List.remove1.
   570 
   571 * Code generation: ML and OCaml code is decorated with signatures.
   572 
   573 * Theory List: added transpose.
   574 
   575 * Library/Nat_Bijection.thy is a collection of bijective functions
   576 between nat and other types, which supersedes the older libraries
   577 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
   578 
   579   Constants:
   580   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
   581   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
   582   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
   583   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
   584   Countable.pair_encode           ~> prod_encode
   585   NatIso.prod2nat                 ~> prod_encode
   586   NatIso.nat2prod                 ~> prod_decode
   587   NatIso.sum2nat                  ~> sum_encode
   588   NatIso.nat2sum                  ~> sum_decode
   589   NatIso.list2nat                 ~> list_encode
   590   NatIso.nat2list                 ~> list_decode
   591   NatIso.set2nat                  ~> set_encode
   592   NatIso.nat2set                  ~> set_decode
   593 
   594   Lemmas:
   595   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
   596   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
   597   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
   598   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
   599   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
   600   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
   601   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
   602   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
   603   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
   604   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
   605   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
   606   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
   607   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
   608 
   609 * Sledgehammer:
   610   - Renamed ATP commands:
   611     atp_info     ~> sledgehammer running_atps
   612     atp_kill     ~> sledgehammer kill_atps
   613     atp_messages ~> sledgehammer messages
   614     atp_minimize ~> sledgehammer minimize
   615     print_atps   ~> sledgehammer available_atps
   616     INCOMPATIBILITY.
   617   - Added user's manual ("isabelle doc sledgehammer").
   618   - Added option syntax and "sledgehammer_params" to customize
   619     Sledgehammer's behavior.  See the manual for details.
   620   - Modified the Isar proof reconstruction code so that it produces
   621     direct proofs rather than proofs by contradiction.  (This feature
   622     is still experimental.)
   623   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
   624     full-typed mode.
   625   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
   626 
   627 * Nitpick:
   628   - Added and implemented "binary_ints" and "bits" options.
   629   - Added "std" option and implemented support for nonstandard models.
   630   - Added and implemented "finitize" option to improve the precision
   631     of infinite datatypes based on a monotonicity analysis.
   632   - Added support for quotient types.
   633   - Added support for "specification" and "ax_specification"
   634     constructs.
   635   - Added support for local definitions (for "function" and
   636     "termination" proofs).
   637   - Added support for term postprocessors.
   638   - Optimized "Multiset.multiset" and "FinFun.finfun".
   639   - Improved efficiency of "destroy_constrs" optimization.
   640   - Fixed soundness bugs related to "destroy_constrs" optimization and
   641     record getters.
   642   - Fixed soundness bug related to higher-order constructors.
   643   - Fixed soundness bug when "full_descrs" is enabled.
   644   - Improved precision of set constructs.
   645   - Added "atoms" option.
   646   - Added cache to speed up repeated Kodkod invocations on the same
   647     problems.
   648   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
   649     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
   650     "SAT4J_Light".  INCOMPATIBILITY.
   651   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
   652     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
   653   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
   654 
   655 * Method "induct" now takes instantiations of the form t, where t is not
   656   a variable, as a shorthand for "x == t", where x is a fresh variable.
   657   If this is not intended, t has to be enclosed in parentheses.
   658   By default, the equalities generated by definitional instantiations
   659   are pre-simplified, which may cause parameters of inductive cases
   660   to disappear, or may even delete some of the inductive cases.
   661   Use "induct (no_simp)" instead of "induct" to restore the old
   662   behaviour. The (no_simp) option is also understood by the "cases"
   663   and "nominal_induct" methods, which now perform pre-simplification, too.
   664   INCOMPATIBILITY.
   665 
   666 
   667 *** HOLCF ***
   668 
   669 * Variable names in lemmas generated by the domain package have
   670 changed; the naming scheme is now consistent with the HOL datatype
   671 package.  Some proof scripts may be affected, INCOMPATIBILITY.
   672 
   673 * The domain package no longer defines the function "foo_copy" for
   674 recursive domain "foo".  The reach lemma is now stated directly in
   675 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
   676 be reformulated in terms of "foo_take", INCOMPATIBILITY.
   677 
   678 * Most definedness lemmas generated by the domain package (previously
   679 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
   680 like "foo$x = UU <-> x = UU", which works better as a simp rule.
   681 Proofs that used definedness lemmas as intro rules may break,
   682 potential INCOMPATIBILITY.
   683 
   684 * Induction and casedist rules generated by the domain package now
   685 declare proper case_names (one called "bottom", and one named for each
   686 constructor).  INCOMPATIBILITY.
   687 
   688 * For mutually-recursive domains, separate "reach" and "take_lemma"
   689 rules are generated for each domain, INCOMPATIBILITY.
   690 
   691   foo_bar.reach       ~> foo.reach  bar.reach
   692   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
   693 
   694 * Some lemmas generated by the domain package have been renamed for
   695 consistency with the datatype package, INCOMPATIBILITY.
   696 
   697   foo.ind        ~> foo.induct
   698   foo.finite_ind ~> foo.finite_induct
   699   foo.coind      ~> foo.coinduct
   700   foo.casedist   ~> foo.exhaust
   701   foo.exhaust    ~> foo.nchotomy
   702 
   703 * For consistency with other definition packages, the fixrec package
   704 now generates qualified theorem names, INCOMPATIBILITY.
   705 
   706   foo_simps  ~> foo.simps
   707   foo_unfold ~> foo.unfold
   708   foo_induct ~> foo.induct
   709 
   710 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
   711 method and internal fixrec proofs now use the default simpset instead.
   712 INCOMPATIBILITY.
   713 
   714 * The "contlub" predicate has been removed.  Proof scripts should use
   715 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
   716 
   717 * The "admw" predicate has been removed, INCOMPATIBILITY.
   718 
   719 * The constants cpair, cfst, and csnd have been removed in favor of
   720 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
   721 
   722 
   723 *** ML ***
   724 
   725 * Antiquotations for basic formal entities:
   726 
   727     @{class NAME}         -- type class
   728     @{class_syntax NAME}  -- syntax representation of the above
   729 
   730     @{type_name NAME}     -- logical type
   731     @{type_abbrev NAME}   -- type abbreviation
   732     @{nonterminal NAME}   -- type of concrete syntactic category
   733     @{type_syntax NAME}   -- syntax representation of any of the above
   734 
   735     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
   736     @{const_abbrev NAME}  -- abbreviated constant
   737     @{const_syntax NAME}  -- syntax representation of any of the above
   738 
   739 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
   740 syntax constant (cf. 'syntax' command).
   741 
   742 * Antiquotation @{make_string} inlines a function to print arbitrary
   743 values similar to the ML toplevel.  The result is compiler dependent
   744 and may fall back on "?" in certain situations.
   745 
   746 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
   747 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
   748 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
   749 not work with the asynchronous Isar document model.
   750 
   751 * Configuration options now admit dynamic default values, depending on
   752 the context or even global references.
   753 
   754 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
   755 uses an efficient external library if available (for Poly/ML).
   756 
   757 * Renamed some important ML structures, while keeping the old names
   758 for some time as aliases within the structure Legacy:
   759 
   760   OuterKeyword  ~>  Keyword
   761   OuterLex      ~>  Token
   762   OuterParse    ~>  Parse
   763   OuterSyntax   ~>  Outer_Syntax
   764   PrintMode     ~>  Print_Mode
   765   SpecParse     ~>  Parse_Spec
   766   ThyInfo       ~>  Thy_Info
   767   ThyLoad       ~>  Thy_Load
   768   ThyOutput     ~>  Thy_Output
   769   TypeInfer     ~>  Type_Infer
   770 
   771 Note that "open Legacy" simplifies porting of sources, but forgetting
   772 to remove it again will complicate porting again in the future.
   773 
   774 * Most operations that refer to a global context are named
   775 accordingly, e.g. Simplifier.global_context or
   776 ProofContext.init_global.  There are some situations where a global
   777 context actually works, but under normal circumstances one needs to
   778 pass the proper local context through the code!
   779 
   780 * Discontinued old TheoryDataFun with its copy/init operation -- data
   781 needs to be pure.  Functor Theory_Data_PP retains the traditional
   782 Pretty.pp argument to merge, which is absent in the standard
   783 Theory_Data version.
   784 
   785 * Sorts.certify_sort and derived "cert" operations for types and terms
   786 no longer minimize sorts.  Thus certification at the boundary of the
   787 inference kernel becomes invariant under addition of class relations,
   788 which is an important monotonicity principle.  Sorts are now minimized
   789 in the syntax layer only, at the boundary between the end-user and the
   790 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
   791 explicitly in rare situations.
   792 
   793 * Renamed old-style Drule.standard to Drule.export_without_context, to
   794 emphasize that this is in no way a standard operation.
   795 INCOMPATIBILITY.
   796 
   797 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
   798 usual for resolution.  Rare INCOMPATIBILITY.
   799 
   800 * Renamed varify/unvarify operations to varify_global/unvarify_global
   801 to emphasize that these only work in a global situation (which is
   802 quite rare).
   803 
   804 * Curried take and drop in library.ML; negative length is interpreted
   805 as infinity (as in chop).  Subtle INCOMPATIBILITY.
   806 
   807 * Proof terms: type substitutions on proof constants now use canonical
   808 order of type variables.  INCOMPATIBILITY for tools working with proof
   809 terms.
   810 
   811 * Raw axioms/defs may no longer carry sort constraints, and raw defs
   812 may no longer carry premises.  User-level specifications are
   813 transformed accordingly by Thm.add_axiom/add_def.
   814 
   815 
   816 *** System ***
   817 
   818 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
   819 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
   820 proof terms are enabled unconditionally in the new HOL-Proofs image.
   821 
   822 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
   823 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
   824 respectively.
   825 
   826 * Old lib/scripts/polyml-platform is superseded by the
   827 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
   828 variant, even on a 64 bit machine.  The following example setting
   829 prefers 64 bit if available:
   830 
   831   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
   832 
   833 * The preliminary Isabelle/jEdit application demonstrates the emerging
   834 Isabelle/Scala layer for advanced prover interaction and integration.
   835 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
   836 component.
   837 
   838 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
   839 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
   840 similar to the default assignment of the document preparation system
   841 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
   842 provides some operations for direct access to the font without asking
   843 the user for manual installation.
   844 
   845 
   846 
   847 New in Isabelle2009-1 (December 2009)
   848 -------------------------------------
   849 
   850 *** General ***
   851 
   852 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
   853 one backslash should be used, even in ML sources.
   854 
   855 
   856 *** Pure ***
   857 
   858 * Locale interpretation propagates mixins along the locale hierarchy.
   859 The currently only available mixins are the equations used to map
   860 local definitions to terms of the target domain of an interpretation.
   861 
   862 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
   863 loc" to print all interpretations of locale "loc" in the theory.
   864 Interpretations in proofs are not shown.
   865 
   866 * Thoroughly revised locales tutorial.  New section on conditional
   867 interpretation.
   868 
   869 * On instantiation of classes, remaining undefined class parameters
   870 are formally declared.  INCOMPATIBILITY.
   871 
   872 
   873 *** Document preparation ***
   874 
   875 * New generalized style concept for printing terms: @{foo (style) ...}
   876 instead of @{foo_style style ...}  (old form is still retained for
   877 backward compatibility).  Styles can be also applied for
   878 antiquotations prop, term_type and typeof.
   879 
   880 
   881 *** HOL ***
   882 
   883 * New proof method "smt" for a combination of first-order logic with
   884 equality, linear and nonlinear (natural/integer/real) arithmetic, and
   885 fixed-size bitvectors; there is also basic support for higher-order
   886 features (esp. lambda abstractions).  It is an incomplete decision
   887 procedure based on external SMT solvers using the oracle mechanism;
   888 for the SMT solver Z3, this method is proof-producing.  Certificates
   889 are provided to avoid calling the external solvers solely for
   890 re-checking proofs.  Due to a remote SMT service there is no need for
   891 installing SMT solvers locally.  See src/HOL/SMT.
   892 
   893 * New commands to load and prove verification conditions generated by
   894 the Boogie program verifier or derived systems (e.g. the Verifying C
   895 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
   896 
   897 * New counterexample generator tool 'nitpick' based on the Kodkod
   898 relational model finder.  See src/HOL/Tools/Nitpick and
   899 src/HOL/Nitpick_Examples.
   900 
   901 * New commands 'code_pred' and 'values' to invoke the predicate
   902 compiler and to enumerate values of inductive predicates.
   903 
   904 * A tabled implementation of the reflexive transitive closure.
   905 
   906 * New implementation of quickcheck uses generic code generator;
   907 default generators are provided for all suitable HOL types, records
   908 and datatypes.  Old quickcheck can be re-activated importing theory
   909 Library/SML_Quickcheck.
   910 
   911 * New testing tool Mirabelle for automated proof tools.  Applies
   912 several tools and tactics like sledgehammer, metis, or quickcheck, to
   913 every proof step in a theory.  To be used in batch mode via the
   914 "mirabelle" utility.
   915 
   916 * New proof method "sos" (sum of squares) for nonlinear real
   917 arithmetic (originally due to John Harison). It requires theory
   918 Library/Sum_Of_Squares.  It is not a complete decision procedure but
   919 works well in practice on quantifier-free real arithmetic with +, -,
   920 *, ^, =, <= and <, i.e. boolean combinations of equalities and
   921 inequalities between polynomials.  It makes use of external
   922 semidefinite programming solvers.  Method "sos" generates a
   923 certificate that can be pasted into the proof thus avoiding the need
   924 to call an external tool every time the proof is checked.  See
   925 src/HOL/Library/Sum_Of_Squares.
   926 
   927 * New method "linarith" invokes existing linear arithmetic decision
   928 procedure only.
   929 
   930 * New command 'atp_minimal' reduces result produced by Sledgehammer.
   931 
   932 * New Sledgehammer option "Full Types" in Proof General settings menu.
   933 Causes full type information to be output to the ATPs.  This slows
   934 ATPs down considerably but eliminates a source of unsound "proofs"
   935 that fail later.
   936 
   937 * New method "metisFT": A version of metis that uses full type
   938 information in order to avoid failures of proof reconstruction.
   939 
   940 * New evaluator "approximate" approximates an real valued term using
   941 the same method as the approximation method.
   942 
   943 * Method "approximate" now supports arithmetic expressions as
   944 boundaries of intervals and implements interval splitting and Taylor
   945 series expansion.
   946 
   947 * ML antiquotation @{code_datatype} inserts definition of a datatype
   948 generated by the code generator; e.g. see src/HOL/Predicate.thy.
   949 
   950 * New theory SupInf of the supremum and infimum operators for sets of
   951 reals.
   952 
   953 * New theory Probability, which contains a development of measure
   954 theory, eventually leading to Lebesgue integration and probability.
   955 
   956 * Extended Multivariate Analysis to include derivation and Brouwer's
   957 fixpoint theorem.
   958 
   959 * Reorganization of number theory, INCOMPATIBILITY:
   960   - new number theory development for nat and int, in theories Divides
   961     and GCD as well as in new session Number_Theory
   962   - some constants and facts now suffixed with _nat and _int
   963     accordingly
   964   - former session NumberTheory now named Old_Number_Theory, including
   965     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
   966   - moved theory Pocklington from src/HOL/Library to
   967     src/HOL/Old_Number_Theory
   968 
   969 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
   970 lcm of finite and infinite sets. It is shown that they form a complete
   971 lattice.
   972 
   973 * Class semiring_div requires superclass no_zero_divisors and proof of
   974 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
   975 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
   976 generalized to class semiring_div, subsuming former theorems
   977 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
   978 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
   979 INCOMPATIBILITY.
   980 
   981 * Refinements to lattice classes and sets:
   982   - less default intro/elim rules in locale variant, more default
   983     intro/elim rules in class variant: more uniformity
   984   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
   985     le_inf_iff
   986   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
   987     sup_aci)
   988   - renamed ACI to inf_sup_aci
   989   - new class "boolean_algebra"
   990   - class "complete_lattice" moved to separate theory
   991     "Complete_Lattice"; corresponding constants (and abbreviations)
   992     renamed and with authentic syntax:
   993     Set.Inf ~>    Complete_Lattice.Inf
   994     Set.Sup ~>    Complete_Lattice.Sup
   995     Set.INFI ~>   Complete_Lattice.INFI
   996     Set.SUPR ~>   Complete_Lattice.SUPR
   997     Set.Inter ~>  Complete_Lattice.Inter
   998     Set.Union ~>  Complete_Lattice.Union
   999     Set.INTER ~>  Complete_Lattice.INTER
  1000     Set.UNION ~>  Complete_Lattice.UNION
  1001   - authentic syntax for
  1002     Set.Pow
  1003     Set.image
  1004   - mere abbreviations:
  1005     Set.empty               (for bot)
  1006     Set.UNIV                (for top)
  1007     Set.inter               (for inf, formerly Set.Int)
  1008     Set.union               (for sup, formerly Set.Un)
  1009     Complete_Lattice.Inter  (for Inf)
  1010     Complete_Lattice.Union  (for Sup)
  1011     Complete_Lattice.INTER  (for INFI)
  1012     Complete_Lattice.UNION  (for SUPR)
  1013   - object-logic definitions as far as appropriate
  1014 
  1015 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1016 Un_subset_iff are explicitly deleted as default simp rules; then also
  1017 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1018 deleted to achieve the desired effect.
  1019 
  1020 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1021 rules by default any longer; the same applies to min_max.inf_absorb1
  1022 etc.  INCOMPATIBILITY.
  1023 
  1024 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1025 pred_set_conv by default.  INCOMPATIBILITY.
  1026 
  1027 * Power operations on relations and functions are now one dedicated
  1028 constant "compow" with infix syntax "^^".  Power operation on
  1029 multiplicative monoids retains syntax "^" and is now defined generic
  1030 in class power.  INCOMPATIBILITY.
  1031 
  1032 * Relation composition "R O S" now has a more standard argument order:
  1033 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1034 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1035 break, since the O_assoc rule was not rewritten like this.  Fix using
  1036 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1037 
  1038 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1039 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1040 INCOMPATIBILITY.
  1041 
  1042 * Most rules produced by inductive and datatype package have mandatory
  1043 prefixes.  INCOMPATIBILITY.
  1044 
  1045 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1046 the attribute of the same name.  Each of the theorems in the list
  1047 DERIV_intros assumes composition with an additional function and
  1048 matches a variable to the derivative, which has to be solved by the
  1049 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1050 of most elementary terms.  Former Maclauren.DERIV_tac and
  1051 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1052 INCOMPATIBILITY.
  1053 
  1054 * Code generator attributes follow the usual underscore convention:
  1055     code_unfold     replaces    code unfold
  1056     code_post       replaces    code post
  1057     etc.
  1058   INCOMPATIBILITY.
  1059 
  1060 * Renamed methods:
  1061     sizechange -> size_change
  1062     induct_scheme -> induction_schema
  1063   INCOMPATIBILITY.
  1064 
  1065 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1066 INCOMPATIBILITY, use "undefined" directly.
  1067 
  1068 * Renamed theorems:
  1069     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1070     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1071     Suc_plus1 -> Suc_eq_plus1
  1072     *anti_sym -> *antisym*
  1073     vector_less_eq_def -> vector_le_def
  1074   INCOMPATIBILITY.
  1075 
  1076 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1077 INCOMPATIBILITY.
  1078 
  1079 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1080 INCOMPATIBILITY.
  1081 
  1082 
  1083 *** HOLCF ***
  1084 
  1085 * Theory Representable defines a class "rep" of domains that are
  1086 representable (via an ep-pair) in the universal domain type "udom".
  1087 Instances are provided for all type constructors defined in HOLCF.
  1088 
  1089 * The 'new_domain' command is a purely definitional version of the
  1090 domain package, for representable domains.  Syntax is identical to the
  1091 old domain package.  The 'new_domain' package also supports indirect
  1092 recursion using previously-defined type constructors.  See
  1093 src/HOLCF/ex/New_Domain.thy for examples.
  1094 
  1095 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1096 on the left-hand side of an equation, and then performs
  1097 simplification.  Rewriting is done using rules declared with the
  1098 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1099 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1100 
  1101 * The pattern-match compiler in 'fixrec' can now handle constructors
  1102 with HOL function types.  Pattern-match combinators for the Pair
  1103 constructor are pre-configured.
  1104 
  1105 * The 'fixrec' package now produces better fixed-point induction rules
  1106 for mutually-recursive definitions:  Induction rules have conclusions
  1107 of the form "P foo bar" instead of "P <foo, bar>".
  1108 
  1109 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1110 been renamed to "below".  The name "below" now replaces "less" in many
  1111 theorem names.  (Legacy theorem names using "less" are still supported
  1112 as well.)
  1113 
  1114 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1115 patterns can be used to generate strictness rules, or to make
  1116 functions more strict (much like the bang-patterns supported by the
  1117 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1118 examples.
  1119 
  1120 
  1121 *** ML ***
  1122 
  1123 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1124 errors and run-time exceptions, including detailed source positions.
  1125 
  1126 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1127 identified entries, with some additional information such as source
  1128 position, logical grouping etc.
  1129 
  1130 * Theory and context data is now introduced by the simplified and
  1131 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1132 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1133 copy operation) is still available for some time.
  1134 
  1135 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1136 provides a high-level programming interface to synchronized state
  1137 variables with atomic update.  This works via pure function
  1138 application within a critical section -- its runtime should be as
  1139 short as possible; beware of deadlocks if critical code is nested,
  1140 either directly or indirectly via other synchronized variables!
  1141 
  1142 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1143 wraps raw ML references, explicitly indicating their non-thread-safe
  1144 behaviour.  The Isar toplevel keeps this structure open, to
  1145 accommodate Proof General as well as quick and dirty interactive
  1146 experiments with references.
  1147 
  1148 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1149 parallel tactical reasoning.
  1150 
  1151 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1152 are similar to SUBPROOF, but are slightly more flexible: only the
  1153 specified parts of the subgoal are imported into the context, and the
  1154 body tactic may introduce new subgoals and schematic variables.
  1155 
  1156 * Old tactical METAHYPS, which does not observe the proof context, has
  1157 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1158 or Subgoal.FOCUS etc.
  1159 
  1160 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1161 functors have their own ML name space there is no point to mark them
  1162 separately.)  Minor INCOMPATIBILITY.
  1163 
  1164 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1165 
  1166 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1167 INCOMPATIBILITY.
  1168 
  1169 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1170 mode, which avoids critical setmp.
  1171 
  1172 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1173 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1174 Attrib/Method.setup introduced in Isabelle2009.
  1175 
  1176 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1177 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1178 last resort.  INCOMPATIBILITY.
  1179 
  1180 * Display.pretty_thm now requires a proper context (cf. former
  1181 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1182 or even Display.pretty_thm_without_context as last resort.
  1183 INCOMPATIBILITY.
  1184 
  1185 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1186 Syntax.pretty_typ/term directly, preferably with proper context
  1187 instead of global theory.
  1188 
  1189 
  1190 *** System ***
  1191 
  1192 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1193 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1194 usedir option -q.
  1195 
  1196 * Support for additional "Isabelle components" via etc/components, see
  1197 also the system manual.
  1198 
  1199 * The isabelle makeall tool now operates on all components with
  1200 IsaMakefile, not just hardwired "logics".
  1201 
  1202 * Removed "compress" option from isabelle-process and isabelle usedir;
  1203 this is always enabled.
  1204 
  1205 * Discontinued support for Poly/ML 4.x versions.
  1206 
  1207 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  1208 on a given logic image.  This requires the lighttpd webserver and is
  1209 currently supported on Linux only.
  1210 
  1211 
  1212 
  1213 New in Isabelle2009 (April 2009)
  1214 --------------------------------
  1215 
  1216 *** General ***
  1217 
  1218 * Simplified main Isabelle executables, with less surprises on
  1219 case-insensitive file-systems (such as Mac OS).
  1220 
  1221   - The main Isabelle tool wrapper is now called "isabelle" instead of
  1222     "isatool."
  1223 
  1224   - The former "isabelle" alias for "isabelle-process" has been
  1225     removed (should rarely occur to regular users).
  1226 
  1227   - The former "isabelle-interface" and its alias "Isabelle" have been
  1228     removed (interfaces are now regular Isabelle tools).
  1229 
  1230 Within scripts and make files, the Isabelle environment variables
  1231 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  1232 respectively.  (The latter are still available as legacy feature.)
  1233 
  1234 The old isabelle-interface wrapper could react in confusing ways if
  1235 the interface was uninstalled or changed otherwise.  Individual
  1236 interface tool configuration is now more explicit, see also the
  1237 Isabelle system manual.  In particular, Proof General is now available
  1238 via "isabelle emacs".
  1239 
  1240 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  1241 purge installed copies of Isabelle executables and re-run "isabelle
  1242 install -p ...", or use symlinks.
  1243 
  1244 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  1245 old ~/isabelle, which was slightly non-standard and apt to cause
  1246 surprises on case-insensitive file-systems (such as Mac OS).
  1247 
  1248 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  1249 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  1250 care is required when using older releases of Isabelle.  Note that
  1251 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  1252 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  1253 
  1254 * Proofs of fully specified statements are run in parallel on
  1255 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  1256 a regular 4-core machine, if the initial heap space is made reasonably
  1257 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  1258 
  1259 * The main reference manuals ("isar-ref", "implementation", and
  1260 "system") have been updated and extended.  Formally checked references
  1261 as hyperlinks are now available uniformly.
  1262 
  1263 
  1264 *** Pure ***
  1265 
  1266 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  1267 respects.  The most important changes are listed below.  See the
  1268 Tutorial on Locales ("locales" manual) for details.
  1269 
  1270 - In locale expressions, instantiation replaces renaming.  Parameters
  1271 must be declared in a for clause.  To aid compatibility with previous
  1272 parameter inheritance, in locale declarations, parameters that are not
  1273 'touched' (instantiation position "_" or omitted) are implicitly added
  1274 with their syntax at the beginning of the for clause.
  1275 
  1276 - Syntax from abbreviations and definitions in locales is available in
  1277 locale expressions and context elements.  The latter is particularly
  1278 useful in locale declarations.
  1279 
  1280 - More flexible mechanisms to qualify names generated by locale
  1281 expressions.  Qualifiers (prefixes) may be specified in locale
  1282 expressions, and can be marked as mandatory (syntax: "name!:") or
  1283 optional (syntax "name?:").  The default depends for plain "name:"
  1284 depends on the situation where a locale expression is used: in
  1285 commands 'locale' and 'sublocale' prefixes are optional, in
  1286 'interpretation' and 'interpret' prefixes are mandatory.  The old
  1287 implicit qualifiers derived from the parameter names of a locale are
  1288 no longer generated.
  1289 
  1290 - Command "sublocale l < e" replaces "interpretation l < e".  The
  1291 instantiation clause in "interpretation" and "interpret" (square
  1292 brackets) is no longer available.  Use locale expressions.
  1293 
  1294 - When converting proof scripts, mandatory qualifiers in
  1295 'interpretation' and 'interpret' should be retained by default, even
  1296 if this is an INCOMPATIBILITY compared to former behavior.  In the
  1297 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  1298 in locale expressions range over a single locale instance only.
  1299 
  1300 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  1301 In existing theorem specifications replace the includes element by the
  1302 respective context elements of the included locale, omitting those
  1303 that are already present in the theorem specification.  Multiple
  1304 assume elements of a locale should be replaced by a single one
  1305 involving the locale predicate.  In the proof body, declarations (most
  1306 notably theorems) may be regained by interpreting the respective
  1307 locales in the proof context as required (command "interpret").
  1308 
  1309 If using "includes" in replacement of a target solely because the
  1310 parameter types in the theorem are not as general as in the target,
  1311 consider declaring a new locale with additional type constraints on
  1312 the parameters (context element "constrains").
  1313 
  1314 - Discontinued "locale (open)".  INCOMPATIBILITY.
  1315 
  1316 - Locale interpretation commands no longer attempt to simplify goal.
  1317 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  1318 methods intro_locales and unfold_locales to clarify.
  1319 
  1320 - Locale interpretation commands no longer accept interpretation
  1321 attributes.  INCOMPATIBILITY.
  1322 
  1323 * Class declaration: so-called "base sort" must not be given in import
  1324 list any longer, but is inferred from the specification.  Particularly
  1325 in HOL, write
  1326 
  1327     class foo = ...
  1328 
  1329 instead of
  1330 
  1331     class foo = type + ...
  1332 
  1333 * Class target: global versions of theorems stemming do not carry a
  1334 parameter prefix any longer.  INCOMPATIBILITY.
  1335 
  1336 * Class 'instance' command no longer accepts attached definitions.
  1337 INCOMPATIBILITY, use proper 'instantiation' target instead.
  1338 
  1339 * Recovered hiding of consts, which was accidentally broken in
  1340 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  1341 makes c inaccessible; consider using ``hide (open) const c'' instead.
  1342 
  1343 * Slightly more coherent Pure syntax, with updated documentation in
  1344 isar-ref manual.  Removed locales meta_term_syntax and
  1345 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  1346 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  1347 directly in regular applications.
  1348 
  1349 * There is a new syntactic category "float_const" for signed decimal
  1350 fractions (e.g. 123.45 or -123.45).
  1351 
  1352 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  1353 interface with 'setup' command instead.
  1354 
  1355 * Command 'local_setup' is similar to 'setup', but operates on a local
  1356 theory context.
  1357 
  1358 * The 'axiomatization' command now only works within a global theory
  1359 context.  INCOMPATIBILITY.
  1360 
  1361 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  1362 hypotheses.  Sorts required in the course of reasoning need to be
  1363 covered by the constraints in the initial statement, completed by the
  1364 type instance information of the background theory.  Non-trivial sort
  1365 hypotheses, which rarely occur in practice, may be specified via
  1366 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  1367 
  1368   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  1369 
  1370 The result contains an implicit sort hypotheses as before --
  1371 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  1372 normalization.
  1373 
  1374 * Generalized Isar history, with support for linear undo, direct state
  1375 addressing etc.
  1376 
  1377 * Changed defaults for unify configuration options:
  1378 
  1379   unify_trace_bound = 50 (formerly 25)
  1380   unify_search_bound = 60 (formerly 30)
  1381 
  1382 * Different bookkeeping for code equations (INCOMPATIBILITY):
  1383 
  1384   a) On theory merge, the last set of code equations for a particular
  1385      constant is taken (in accordance with the policy applied by other
  1386      parts of the code generator framework).
  1387 
  1388   b) Code equations stemming from explicit declarations (e.g. code
  1389      attribute) gain priority over default code equations stemming
  1390      from definition, primrec, fun etc.
  1391 
  1392 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  1393 
  1394 * Unified theorem tables for both code generators.  Thus [code
  1395 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  1396 
  1397 * Command 'find_consts' searches for constants based on type and name
  1398 patterns, e.g.
  1399 
  1400     find_consts "_ => bool"
  1401 
  1402 By default, matching is against subtypes, but it may be restricted to
  1403 the whole type.  Searching by name is possible.  Multiple queries are
  1404 conjunctive and queries may be negated by prefixing them with a
  1405 hyphen:
  1406 
  1407     find_consts strict: "_ => bool" name: "Int" -"int => int"
  1408 
  1409 * New 'find_theorems' criterion "solves" matches theorems that
  1410 directly solve the current goal (modulo higher-order unification).
  1411 
  1412 * Auto solve feature for main theorem statements: whenever a new goal
  1413 is stated, "find_theorems solves" is called; any theorems that could
  1414 solve the lemma directly are listed as part of the goal state.
  1415 Cf. associated options in Proof General Isabelle settings menu,
  1416 enabled by default, with reasonable timeout for pathological cases of
  1417 higher-order unification.
  1418 
  1419 
  1420 *** Document preparation ***
  1421 
  1422 * Antiquotation @{lemma} now imitates a regular terminal proof,
  1423 demanding keyword 'by' and supporting the full method expression
  1424 syntax just like the Isar command 'by'.
  1425 
  1426 
  1427 *** HOL ***
  1428 
  1429 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  1430 points Main and Complex_Main remain as before.
  1431 
  1432 * Logic image HOL-Plain provides a minimal HOL with the most important
  1433 tools available (inductive, datatype, primrec, ...).  This facilitates
  1434 experimentation and tool development.  Note that user applications
  1435 (and library theories) should never refer to anything below theory
  1436 Main, as before.
  1437 
  1438 * Logic image HOL-Main stops at theory Main, and thus facilitates
  1439 experimentation due to shorter build times.
  1440 
  1441 * Logic image HOL-NSA contains theories of nonstandard analysis which
  1442 were previously part of former HOL-Complex.  Entry point Hyperreal
  1443 remains valid, but theories formerly using Complex_Main should now use
  1444 new entry point Hypercomplex.
  1445 
  1446 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  1447 Posix processes.  Avoids potentially expensive forking of the ML
  1448 process.  New thread-based implementation also works on non-Unix
  1449 platforms (Cygwin).  Provers are no longer hardwired, but defined
  1450 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  1451 commands are covered in the isar-ref manual.
  1452 
  1453 * Wrapper scripts for remote SystemOnTPTP service allows to use
  1454 sledgehammer without local ATP installation (Vampire etc.). Other
  1455 provers may be included via suitable ML wrappers, see also
  1456 src/HOL/ATP_Linkup.thy.
  1457 
  1458 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  1459 menu.
  1460 
  1461 * The metis method no longer fails because the theorem is too trivial
  1462 (contains the empty clause).
  1463 
  1464 * The metis method now fails in the usual manner, rather than raising
  1465 an exception, if it determines that it cannot prove the theorem.
  1466 
  1467 * Method "coherent" implements a prover for coherent logic (see also
  1468 src/Tools/coherent.ML).
  1469 
  1470 * Constants "undefined" and "default" replace "arbitrary".  Usually
  1471 "undefined" is the right choice to replace "arbitrary", though
  1472 logically there is no difference.  INCOMPATIBILITY.
  1473 
  1474 * Command "value" now integrates different evaluation mechanisms.  The
  1475 result of the first successful evaluation mechanism is printed.  In
  1476 square brackets a particular named evaluation mechanisms may be
  1477 specified (currently, [SML], [code] or [nbe]).  See further
  1478 src/HOL/ex/Eval_Examples.thy.
  1479 
  1480 * Normalization by evaluation now allows non-leftlinear equations.
  1481 Declare with attribute [code nbe].
  1482 
  1483 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  1484 as the structured Isar versions "cases" and "induct", cf. the
  1485 corresponding "cases" and "induct" attributes.  Mutual induction rules
  1486 are now presented as a list of individual projections
  1487 (e.g. foo_bar.inducts for types foo and bar); the old format with
  1488 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  1489 rare situations a different rule is selected --- notably nested tuple
  1490 elimination instead of former prod.exhaust: use explicit (case_tac t
  1491 rule: prod.exhaust) here.
  1492 
  1493 * Attributes "cases", "induct", "coinduct" support "del" option.
  1494 
  1495 * Removed fact "case_split_thm", which duplicates "case_split".
  1496 
  1497 * The option datatype has been moved to a new theory Option.  Renamed
  1498 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  1499 
  1500 * New predicate "strict_mono" classifies strict functions on partial
  1501 orders.  With strict functions on linear orders, reasoning about
  1502 (in)equalities is facilitated by theorems "strict_mono_eq",
  1503 "strict_mono_less_eq" and "strict_mono_less".
  1504 
  1505 * Some set operations are now proper qualified constants with
  1506 authentic syntax.  INCOMPATIBILITY:
  1507 
  1508     op Int ~>   Set.Int
  1509     op Un ~>    Set.Un
  1510     INTER ~>    Set.INTER
  1511     UNION ~>    Set.UNION
  1512     Inter ~>    Set.Inter
  1513     Union ~>    Set.Union
  1514     {} ~>       Set.empty
  1515     UNIV ~>     Set.UNIV
  1516 
  1517 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  1518 theory Set.
  1519 
  1520 * Auxiliary class "itself" has disappeared -- classes without any
  1521 parameter are treated as expected by the 'class' command.
  1522 
  1523 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  1524 
  1525 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  1526 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  1527 
  1528 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  1529 method "approximation".  It proves formulas on real values by using
  1530 interval arithmetic.  In the formulas are also the transcendental
  1531 functions sin, cos, tan, atan, ln, exp and the constant pi are
  1532 allowed. For examples see
  1533 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  1534 
  1535 * Theory "Reflection" now resides in HOL/Library.
  1536 
  1537 * Entry point to Word library now simply named "Word".
  1538 INCOMPATIBILITY.
  1539 
  1540 * Made source layout more coherent with logical distribution
  1541 structure:
  1542 
  1543     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  1544     src/HOL/Library/Code_Message.thy ~> src/HOL/
  1545     src/HOL/Library/GCD.thy ~> src/HOL/
  1546     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  1547     src/HOL/Library/Parity.thy ~> src/HOL/
  1548     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  1549     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  1550     src/HOL/Real/Lubs.thy ~> src/HOL/
  1551     src/HOL/Real/PReal.thy ~> src/HOL/
  1552     src/HOL/Real/Rational.thy ~> src/HOL/
  1553     src/HOL/Real/RComplete.thy ~> src/HOL/
  1554     src/HOL/Real/RealDef.thy ~> src/HOL/
  1555     src/HOL/Real/RealPow.thy ~> src/HOL/
  1556     src/HOL/Real/Real.thy ~> src/HOL/
  1557     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  1558     src/HOL/Complex/Complex.thy ~> src/HOL/
  1559     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  1560     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  1561     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  1562     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  1563     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  1564     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  1565     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  1566     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  1567     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  1568     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  1569     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  1570     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  1571     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  1572     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  1573     src/HOL/Real/Float ~> src/HOL/Library/
  1574     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  1575     src/HOL/Real/RealVector.thy ~> src/HOL/
  1576 
  1577     src/HOL/arith_data.ML ~> src/HOL/Tools
  1578     src/HOL/hologic.ML ~> src/HOL/Tools
  1579     src/HOL/simpdata.ML ~> src/HOL/Tools
  1580     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  1581     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  1582     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  1583     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  1584     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  1585     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  1586     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  1587 
  1588     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  1589     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  1590     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  1591     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  1592     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  1593     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  1594 
  1595 * If methods "eval" and "evaluation" encounter a structured proof
  1596 state with !!/==>, only the conclusion is evaluated to True (if
  1597 possible), avoiding strange error messages.
  1598 
  1599 * Method "sizechange" automates termination proofs using (a
  1600 modification of) the size-change principle.  Requires SAT solver.  See
  1601 src/HOL/ex/Termination.thy for examples.
  1602 
  1603 * Simplifier: simproc for let expressions now unfolds if bound
  1604 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  1605 
  1606 * Method "arith": Linear arithmetic now ignores all inequalities when
  1607 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  1608 
  1609 * New attribute "arith" for facts that should always be used
  1610 automatically by arithmetic. It is intended to be used locally in
  1611 proofs, e.g.
  1612 
  1613   assumes [arith]: "x > 0"
  1614 
  1615 Global usage is discouraged because of possible performance impact.
  1616 
  1617 * New classes "top" and "bot" with corresponding operations "top" and
  1618 "bot" in theory Orderings; instantiation of class "complete_lattice"
  1619 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  1620 
  1621 * Changed definition lemma "less_fun_def" in order to provide an
  1622 instance for preorders on functions; use lemma "less_le" instead.
  1623 INCOMPATIBILITY.
  1624 
  1625 * Theory Orderings: class "wellorder" moved here, with explicit
  1626 induction rule "less_induct" as assumption.  For instantiation of
  1627 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  1628 INCOMPATIBILITY.
  1629 
  1630 * Theory Orderings: added class "preorder" as superclass of "order".
  1631 INCOMPATIBILITY: Instantiation proofs for order, linorder
  1632 etc. slightly changed.  Some theorems named order_class.* now named
  1633 preorder_class.*.
  1634 
  1635 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  1636 "diag" to "Id_on".
  1637 
  1638 * Theory Finite_Set: added a new fold combinator of type
  1639 
  1640   ('a => 'b => 'b) => 'b => 'a set => 'b
  1641 
  1642 Occasionally this is more convenient than the old fold combinator
  1643 which is now defined in terms of the new one and renamed to
  1644 fold_image.
  1645 
  1646 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  1647 and "ring_simps" have been replaced by "algebra_simps" (which can be
  1648 extended with further lemmas!).  At the moment both still exist but
  1649 the former will disappear at some point.
  1650 
  1651 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  1652 class recpower.  Type-specific simp rules for various recpower types
  1653 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  1654 
  1655 rat_power_0    -> power_0
  1656 rat_power_Suc  -> power_Suc
  1657 realpow_0      -> power_0
  1658 realpow_Suc    -> power_Suc
  1659 complexpow_0   -> power_0
  1660 complexpow_Suc -> power_Suc
  1661 power_poly_0   -> power_0
  1662 power_poly_Suc -> power_Suc
  1663 
  1664 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  1665 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  1666 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  1667 of lemmas from Divides has been generalized from nat to class
  1668 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  1669 renames resulting from duplicate elimination:
  1670 
  1671     dvd_def_mod ~>          dvd_eq_mod_eq_0
  1672     zero_dvd_iff ~>         dvd_0_left_iff
  1673     dvd_0 ~>                dvd_0_right
  1674     DIVISION_BY_ZERO_DIV ~> div_by_0
  1675     DIVISION_BY_ZERO_MOD ~> mod_by_0
  1676     mult_div ~>             div_mult_self2_is_id
  1677     mult_mod ~>             mod_mult_self2_is_0
  1678 
  1679 * Theory IntDiv: removed many lemmas that are instances of class-based
  1680 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  1681 rename old lemmas as follows:
  1682 
  1683 dvd_diff               -> nat_dvd_diff
  1684 dvd_zminus_iff         -> dvd_minus_iff
  1685 mod_add1_eq            -> mod_add_eq
  1686 mod_mult1_eq           -> mod_mult_right_eq
  1687 mod_mult1_eq'          -> mod_mult_left_eq
  1688 mod_mult_distrib_mod   -> mod_mult_eq
  1689 nat_mod_add_left_eq    -> mod_add_left_eq
  1690 nat_mod_add_right_eq   -> mod_add_right_eq
  1691 nat_mod_div_trivial    -> mod_div_trivial
  1692 nat_mod_mod_trivial    -> mod_mod_trivial
  1693 zdiv_zadd_self1        -> div_add_self1
  1694 zdiv_zadd_self2        -> div_add_self2
  1695 zdiv_zmult_self1       -> div_mult_self2_is_id
  1696 zdiv_zmult_self2       -> div_mult_self1_is_id
  1697 zdvd_triv_left         -> dvd_triv_left
  1698 zdvd_triv_right        -> dvd_triv_right
  1699 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  1700 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  1701 zmod_zadd_left_eq      -> mod_add_left_eq
  1702 zmod_zadd_right_eq     -> mod_add_right_eq
  1703 zmod_zadd_self1        -> mod_add_self1
  1704 zmod_zadd_self2        -> mod_add_self2
  1705 zmod_zadd1_eq          -> mod_add_eq
  1706 zmod_zdiff1_eq         -> mod_diff_eq
  1707 zmod_zdvd_zmod         -> mod_mod_cancel
  1708 zmod_zmod_cancel       -> mod_mod_cancel
  1709 zmod_zmult_self1       -> mod_mult_self2_is_0
  1710 zmod_zmult_self2       -> mod_mult_self1_is_0
  1711 zmod_1                 -> mod_by_1
  1712 zdiv_1                 -> div_by_1
  1713 zdvd_abs1              -> abs_dvd_iff
  1714 zdvd_abs2              -> dvd_abs_iff
  1715 zdvd_refl              -> dvd_refl
  1716 zdvd_trans             -> dvd_trans
  1717 zdvd_zadd              -> dvd_add
  1718 zdvd_zdiff             -> dvd_diff
  1719 zdvd_zminus_iff        -> dvd_minus_iff
  1720 zdvd_zminus2_iff       -> minus_dvd_iff
  1721 zdvd_zmultD            -> dvd_mult_right
  1722 zdvd_zmultD2           -> dvd_mult_left
  1723 zdvd_zmult_mono        -> mult_dvd_mono
  1724 zdvd_0_right           -> dvd_0_right
  1725 zdvd_0_left            -> dvd_0_left_iff
  1726 zdvd_1_left            -> one_dvd
  1727 zminus_dvd_iff         -> minus_dvd_iff
  1728 
  1729 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  1730 
  1731 * The real numbers offer decimal input syntax: 12.34 is translated
  1732 into 1234/10^2. This translation is not reversed upon output.
  1733 
  1734 * Theory Library/Polynomial defines an abstract type 'a poly of
  1735 univariate polynomials with coefficients of type 'a.  In addition to
  1736 the standard ring operations, it also supports div and mod.  Code
  1737 generation is also supported, using list-style constructors.
  1738 
  1739 * Theory Library/Inner_Product defines a class of real_inner for real
  1740 inner product spaces, with an overloaded operation inner :: 'a => 'a
  1741 => real.  Class real_inner is a subclass of real_normed_vector from
  1742 theory RealVector.
  1743 
  1744 * Theory Library/Product_Vector provides instances for the product
  1745 type 'a * 'b of several classes from RealVector and Inner_Product.
  1746 Definitions of addition, subtraction, scalar multiplication, norms,
  1747 and inner products are included.
  1748 
  1749 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  1750 addition to the field operations, numerals and case syntax are also
  1751 supported.
  1752 
  1753 * Theory Library/Diagonalize provides constructive version of Cantor's
  1754 first diagonalization argument.
  1755 
  1756 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  1757 zlcm (for int); carried together from various gcd/lcm developements in
  1758 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  1759 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  1760 may recover tupled syntax as follows:
  1761 
  1762     hide (open) const gcd
  1763     abbreviation gcd where
  1764       "gcd == (%(a, b). GCD.gcd a b)"
  1765     notation (output)
  1766       GCD.gcd ("gcd '(_, _')")
  1767 
  1768 The same works for lcm, zgcd, zlcm.
  1769 
  1770 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  1771 instantiations for algebraic structures.  Removed some duplicate
  1772 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  1773 
  1774 * ML antiquotation @{code} takes a constant as argument and generates
  1775 corresponding code in background and inserts name of the corresponding
  1776 resulting ML value/function/datatype constructor binding in place.
  1777 All occurrences of @{code} with a single ML block are generated
  1778 simultaneously.  Provides a generic and safe interface for
  1779 instrumentalizing code generation.  See
  1780 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  1781 In future you ought to refrain from ad-hoc compiling generated SML
  1782 code on the ML toplevel.  Note that (for technical reasons) @{code}
  1783 cannot refer to constants for which user-defined serializations are
  1784 set.  Refer to the corresponding ML counterpart directly in that
  1785 cases.
  1786 
  1787 * Command 'rep_datatype': instead of theorem names the command now
  1788 takes a list of terms denoting the constructors of the type to be
  1789 represented as datatype.  The characteristic theorems have to be
  1790 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  1791 have disappeared in favour of existing ones:
  1792 
  1793     unit_induct                 ~> unit.induct
  1794     prod_induct                 ~> prod.induct
  1795     sum_induct                  ~> sum.induct
  1796     Suc_Suc_eq                  ~> nat.inject
  1797     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  1798 
  1799 
  1800 *** HOL-Algebra ***
  1801 
  1802 * New locales for orders and lattices where the equivalence relation
  1803 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  1804 locales use a record structure with field eq for the equivalence.
  1805 
  1806 * New theory of factorial domains.
  1807 
  1808 * Units_l_inv and Units_r_inv are now simp rules by default.
  1809 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  1810 and/or r_inv will now also require deletion of these lemmas.
  1811 
  1812 * Renamed the following theorems, INCOMPATIBILITY:
  1813 
  1814 UpperD ~> Upper_memD
  1815 LowerD ~> Lower_memD
  1816 least_carrier ~> least_closed
  1817 greatest_carrier ~> greatest_closed
  1818 greatest_Lower_above ~> greatest_Lower_below
  1819 one_zero ~> carrier_one_zero
  1820 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  1821 
  1822 
  1823 *** HOL-Nominal ***
  1824 
  1825 * Nominal datatypes can now contain type-variables.
  1826 
  1827 * Commands 'nominal_inductive' and 'equivariance' work with local
  1828 theory targets.
  1829 
  1830 * Nominal primrec can now works with local theory targets and its
  1831 specification syntax now conforms to the general format as seen in
  1832 'inductive' etc.
  1833 
  1834 * Method "perm_simp" honours the standard simplifier attributes
  1835 (no_asm), (no_asm_use) etc.
  1836 
  1837 * The new predicate #* is defined like freshness, except that on the
  1838 left hand side can be a set or list of atoms.
  1839 
  1840 * Experimental command 'nominal_inductive2' derives strong induction
  1841 principles for inductive definitions.  In contrast to
  1842 'nominal_inductive', which can only deal with a fixed number of
  1843 binders, it can deal with arbitrary expressions standing for sets of
  1844 atoms to be avoided.  The only inductive definition we have at the
  1845 moment that needs this generalisation is the typing rule for Lets in
  1846 the algorithm W:
  1847 
  1848  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  1849  -----------------------------------------------------------------
  1850          Gamma |- Let x be t1 in t2 : T2
  1851 
  1852 In this rule one wants to avoid all the binders that are introduced by
  1853 "close Gamma T1".  We are looking for other examples where this
  1854 feature might be useful.  Please let us know.
  1855 
  1856 
  1857 *** HOLCF ***
  1858 
  1859 * Reimplemented the simplification procedure for proving continuity
  1860 subgoals.  The new simproc is extensible; users can declare additional
  1861 continuity introduction rules with the attribute [cont2cont].
  1862 
  1863 * The continuity simproc now uses a different introduction rule for
  1864 solving continuity subgoals on terms with lambda abstractions.  In
  1865 some rare cases the new simproc may fail to solve subgoals that the
  1866 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  1867 Potential INCOMPATIBILITY.
  1868 
  1869 * Command 'fixrec': specification syntax now conforms to the general
  1870 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  1871 examples.  INCOMPATIBILITY.
  1872 
  1873 
  1874 *** ZF ***
  1875 
  1876 * Proof of Zorn's Lemma for partial orders.
  1877 
  1878 
  1879 *** ML ***
  1880 
  1881 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  1882 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  1883 depends on multithreading, so timouts will not work before Poly/ML
  1884 5.2.1!
  1885 
  1886 * High-level support for concurrent ML programming, see
  1887 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  1888 particularly convenient to organize independent functional
  1889 computations.  The concept of "synchronized variables" provides a
  1890 higher-order interface for components with shared state, avoiding the
  1891 delicate details of mutexes and condition variables.  (Requires
  1892 Poly/ML 5.2.1 or later.)
  1893 
  1894 * ML bindings produced via Isar commands are stored within the Isar
  1895 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  1896 become thread-safe and work with undo as expected (concerning
  1897 top-level bindings, not side-effects on global references).
  1898 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  1899 compiler at runtime; really global bindings need to be given outside a
  1900 theory.  (Requires Poly/ML 5.2 or later.)
  1901 
  1902 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  1903 context.  Top-level ML bindings are stored within the proof context in
  1904 a purely sequential fashion, disregarding the nested proof structure.
  1905 ML bindings introduced by 'ML_prf' are discarded at the end of the
  1906 proof.  (Requires Poly/ML 5.2 or later.)
  1907 
  1908 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  1909 and Method.setup, as well as Isar commands 'attribute_setup' and
  1910 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  1911 existing code accordingly, or use plain 'setup' together with old
  1912 Method.add_method.
  1913 
  1914 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  1915 to 'a -> thm, while results are always tagged with an authentic oracle
  1916 name.  The Isar command 'oracle' is now polymorphic, no argument type
  1917 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  1918 accordingly.  Note that extra performance may be gained by producing
  1919 the cterm carefully, avoiding slow Thm.cterm_of.
  1920 
  1921 * Simplified interface for defining document antiquotations via
  1922 ThyOutput.antiquotation, ThyOutput.output, and optionally
  1923 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  1924 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  1925 examples.
  1926 
  1927 * More systematic treatment of long names, abstract name bindings, and
  1928 name space operations.  Basic operations on qualified names have been
  1929 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  1930 Long_Name.append.  Old type bstring has been mostly replaced by
  1931 abstract type binding (see structure Binding), which supports precise
  1932 qualification by packages and local theory targets, as well as proper
  1933 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  1934 bstring values into Binding.name, or better pass through abstract
  1935 bindings everywhere.  See further src/Pure/General/long_name.ML,
  1936 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  1937 
  1938 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  1939 LocalTheory.note etc.) now refer to the *full* internal name, not the
  1940 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  1941 
  1942 * Disposed old type and term read functions (Sign.read_def_typ,
  1943 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  1944 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  1945 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  1946 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  1947 resort for legacy applications.
  1948 
  1949 * Disposed old declarations, tactics, tactic combinators that refer to
  1950 the simpset or claset of an implicit theory (such as Addsimps,
  1951 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  1952 embedded ML text, or local_simpset_of with a proper context passed as
  1953 explicit runtime argument.
  1954 
  1955 * Rules and tactics that read instantiations (read_instantiate,
  1956 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  1957 context, which is required for parsing and type-checking.  Moreover,
  1958 the variables are specified as plain indexnames, not string encodings
  1959 thereof.  INCOMPATIBILITY.
  1960 
  1961 * Generic Toplevel.add_hook interface allows to analyze the result of
  1962 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  1963 for theorem dependency output of transactions resulting in a new
  1964 theory state.
  1965 
  1966 * ML antiquotations: block-structured compilation context indicated by
  1967 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  1968 
  1969   @{binding name}                         - basic name binding
  1970   @{let ?pat = term}                      - term abbreviation (HO matching)
  1971   @{note name = fact}                     - fact abbreviation
  1972   @{thm fact}                             - singleton fact (with attributes)
  1973   @{thms fact}                            - general fact (with attributes)
  1974   @{lemma prop by method}                 - singleton goal
  1975   @{lemma prop by meth1 meth2}            - singleton goal
  1976   @{lemma prop1 ... propN by method}      - general goal
  1977   @{lemma prop1 ... propN by meth1 meth2} - general goal
  1978   @{lemma (open) ...}                     - open derivation
  1979 
  1980 
  1981 *** System ***
  1982 
  1983 * The Isabelle "emacs" tool provides a specific interface to invoke
  1984 Proof General / Emacs, with more explicit failure if that is not
  1985 installed (the old isabelle-interface script silently falls back on
  1986 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  1987 installation location of the Proof General distribution.
  1988 
  1989 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  1990 the Isabelle process into a JVM/Scala application.  See
  1991 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  1992 process wrapper has been discontinued.)
  1993 
  1994 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  1995 
  1996 * Various status messages (with exact source position information) are
  1997 emitted, if proper markup print mode is enabled.  This allows
  1998 user-interface components to provide detailed feedback on internal
  1999 prover operations.
  2000 
  2001 
  2002 
  2003 New in Isabelle2008 (June 2008)
  2004 -------------------------------
  2005 
  2006 *** General ***
  2007 
  2008 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2009 and updated, with formally checked references as hyperlinks.
  2010 
  2011 * Theory loader: use_thy (and similar operations) no longer set the
  2012 implicit ML context, which was occasionally hard to predict and in
  2013 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2014 provides a proper context already.
  2015 
  2016 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2017 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2018 'use' within a theory file will do the job.
  2019 
  2020 * Name space merge now observes canonical order, i.e. the second space
  2021 is inserted into the first one, while existing entries in the first
  2022 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2023 swap theory imports.
  2024 
  2025 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2026 INCOMPATIBILITY in identifier syntax etc.
  2027 
  2028 * Outer syntax: string tokens no longer admit escaped white space,
  2029 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2030 white space without escapes.
  2031 
  2032 * Outer syntax: string tokens may contain arbitrary character codes
  2033 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2034 "foo_bar".
  2035 
  2036 
  2037 *** Pure ***
  2038 
  2039 * Context-dependent token translations.  Default setup reverts locally
  2040 fixed variables, and adds hilite markup for undeclared frees.
  2041 
  2042 * Unused theorems can be found using the new command 'unused_thms'.
  2043 There are three ways of invoking it:
  2044 
  2045 (1) unused_thms
  2046      Only finds unused theorems in the current theory.
  2047 
  2048 (2) unused_thms thy_1 ... thy_n -
  2049      Finds unused theorems in the current theory and all of its ancestors,
  2050      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2051 
  2052 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2053      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2054      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2055      their ancestors.
  2056 
  2057 In order to increase the readability of the list produced by
  2058 unused_thms, theorems that have been created by a particular instance
  2059 of a theory command such as 'inductive' or 'function' are considered
  2060 to belong to the same "group", meaning that if at least one theorem in
  2061 this group is used, the other theorems in the same group are no longer
  2062 reported as unused.  Moreover, if all theorems in the group are
  2063 unused, only one theorem in the group is displayed.
  2064 
  2065 Note that proof objects have to be switched on in order for
  2066 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2067 usually the case when using Proof General with the default settings).
  2068 
  2069 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2070 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2071 duplicate fact bindings, or even accidental fact duplications.  Note
  2072 that tools may maintain dynamically scoped facts systematically, using
  2073 PureThy.add_thms_dynamic.
  2074 
  2075 * Command 'hide' now allows to hide from "fact" name space as well.
  2076 
  2077 * Eliminated destructive theorem database, simpset, claset, and
  2078 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2079 update of theories within ML code.
  2080 
  2081 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2082 INCOMPATIBILITY, object-logics depending on former Pure require
  2083 additional setup PureThy.old_appl_syntax_setup; object-logics
  2084 depending on former CPure need to refer to Pure.
  2085 
  2086 * Commands 'use' and 'ML' are now purely functional, operating on
  2087 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2088 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2089 INCOMPATIBILITY.
  2090 
  2091 * Command 'setup': discontinued implicit version with ML reference.
  2092 
  2093 * Instantiation target allows for simultaneous specification of class
  2094 instance operations together with an instantiation proof.
  2095 Type-checking phase allows to refer to class operations uniformly.
  2096 See src/HOL/Complex/Complex.thy for an Isar example and
  2097 src/HOL/Library/Eval.thy for an ML example.
  2098 
  2099 * Indexing of literal facts: be more serious about including only
  2100 facts from the visible specification/proof context, but not the
  2101 background context (locale etc.).  Affects `prop` notation and method
  2102 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2103 situations.
  2104 
  2105 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2106 "(open)" option, which used to expose internal bound variables to the
  2107 proof text.
  2108 
  2109 * Isar statements: removed obsolete case "rule_context".
  2110 INCOMPATIBILITY, better use explicit fixes/assumes.
  2111 
  2112 * Locale proofs: default proof step now includes 'unfold_locales';
  2113 hence 'proof' without argument may be used to unfold locale
  2114 predicates.
  2115 
  2116 
  2117 *** Document preparation ***
  2118 
  2119 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2120 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2121 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2122 spot); renamed link color from "darkblue" to "linkcolor" (default
  2123 value unchanged, can be redefined via \definecolor); no longer sets
  2124 "a4paper" option (unnecessary or even intrusive).
  2125 
  2126 * Antiquotation @{lemma A method} proves proposition A by the given
  2127 method (either a method name or a method name plus (optional) method
  2128 arguments in parentheses) and prints A just like @{prop A}.
  2129 
  2130 
  2131 *** HOL ***
  2132 
  2133 * New primrec package.  Specification syntax conforms in style to
  2134 definition/function/....  No separate induction rule is provided.  The
  2135 "primrec" command distinguishes old-style and new-style specifications
  2136 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2137 When adjusting theories, beware: constants stemming from new-style
  2138 primrec specifications have authentic syntax.
  2139 
  2140 * Metis prover is now an order of magnitude faster, and also works
  2141 with multithreading.
  2142 
  2143 * Metis: the maximum number of clauses that can be produced from a
  2144 theorem is now given by the attribute max_clauses.  Theorems that
  2145 exceed this number are ignored, with a warning printed.
  2146 
  2147 * Sledgehammer no longer produces structured proofs by default. To
  2148 enable, declare [[sledgehammer_full = true]].  Attributes
  2149 reconstruction_modulus, reconstruction_sorts renamed
  2150 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2151 
  2152 * Method "induct_scheme" derives user-specified induction rules
  2153 from well-founded induction and completeness of patterns. This factors
  2154 out some operations that are done internally by the function package
  2155 and makes them available separately.  See
  2156 src/HOL/ex/Induction_Scheme.thy for examples.
  2157 
  2158 * More flexible generation of measure functions for termination
  2159 proofs: Measure functions can be declared by proving a rule of the
  2160 form "is_measure f" and giving it the [measure_function] attribute.
  2161 The "is_measure" predicate is logically meaningless (always true), and
  2162 just guides the heuristic.  To find suitable measure functions, the
  2163 termination prover sets up the goal "is_measure ?f" of the appropriate
  2164 type and generates all solutions by prolog-style backwards proof using
  2165 the declared rules.
  2166 
  2167 This setup also deals with rules like 
  2168 
  2169   "is_measure f ==> is_measure (list_size f)"
  2170 
  2171 which accommodates nested datatypes that recurse through lists.
  2172 Similar rules are predeclared for products and option types.
  2173 
  2174 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2175 
  2176   INCOMPATIBILITIES:
  2177 
  2178   - Definitions of overloaded constants on sets have to be replaced by
  2179     definitions on => and bool.
  2180 
  2181   - Some definitions of overloaded operators on sets can now be proved
  2182     using the definitions of the operators on => and bool.  Therefore,
  2183     the following theorems have been renamed:
  2184 
  2185       subset_def   -> subset_eq
  2186       psubset_def  -> psubset_eq
  2187       set_diff_def -> set_diff_eq
  2188       Compl_def    -> Compl_eq
  2189       Sup_set_def  -> Sup_set_eq
  2190       Inf_set_def  -> Inf_set_eq
  2191       sup_set_def  -> sup_set_eq
  2192       inf_set_def  -> inf_set_eq
  2193 
  2194   - Due to the incompleteness of the HO unification algorithm, some
  2195     rules such as subst may require manual instantiation, if some of
  2196     the unknowns in the rule is a set.
  2197 
  2198   - Higher order unification and forward proofs:
  2199     The proof pattern
  2200 
  2201       have "P (S::'a set)" <...>
  2202       then have "EX S. P S" ..
  2203 
  2204     no longer works (due to the incompleteness of the HO unification
  2205     algorithm) and must be replaced by the pattern
  2206 
  2207       have "EX S. P S"
  2208       proof
  2209         show "P S" <...>
  2210       qed
  2211 
  2212   - Calculational reasoning with subst (or similar rules):
  2213     The proof pattern
  2214 
  2215       have "P (S::'a set)" <...>
  2216       also have "S = T" <...>
  2217       finally have "P T" .
  2218 
  2219     no longer works (for similar reasons as the previous example) and
  2220     must be replaced by something like
  2221 
  2222       have "P (S::'a set)" <...>
  2223       moreover have "S = T" <...>
  2224       ultimately have "P T" by simp
  2225 
  2226   - Tactics or packages written in ML code:
  2227     Code performing pattern matching on types via
  2228 
  2229       Type ("set", [T]) => ...
  2230 
  2231     must be rewritten. Moreover, functions like strip_type or
  2232     binder_types no longer return the right value when applied to a
  2233     type of the form
  2234 
  2235       T1 => ... => Tn => U => bool
  2236 
  2237     rather than
  2238 
  2239       T1 => ... => Tn => U set
  2240 
  2241 * Merged theories Wellfounded_Recursion, Accessible_Part and
  2242 Wellfounded_Relations to theory Wellfounded.
  2243 
  2244 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  2245 
  2246 * Class finite no longer treats UNIV as class parameter.  Use class
  2247 enum from theory Library/Enum instead to achieve a similar effect.
  2248 INCOMPATIBILITY.
  2249 
  2250 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  2251 and "Cons".  INCOMPATIBILITY.
  2252 
  2253 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  2254 Potential INCOMPATIBILITY.
  2255 
  2256 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  2257 injective_fst_snd removed, use split_eta and prod_eqI instead.
  2258 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  2259 
  2260 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  2261 the same name in theory Orderings:
  2262 
  2263   less_trans
  2264   less_linear
  2265   le_imp_less_or_eq
  2266   le_less_trans
  2267   less_le_trans
  2268   less_not_sym
  2269   less_asym
  2270 
  2271 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  2272 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  2273 and different variable names.
  2274 
  2275 * Library/Option_ord.thy: Canonical order on option type.
  2276 
  2277 * Library/RBT.thy: Red-black trees, an efficient implementation of
  2278 finite maps.
  2279 
  2280 * Library/Countable.thy: Type class for countable types.
  2281 
  2282 * Theory Int: The representation of numerals has changed.  The infix
  2283 operator BIT and the bit datatype with constructors B0 and B1 have
  2284 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  2285 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  2286 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  2287 accordingly.
  2288 
  2289 * Theory Nat: definition of <= and < on natural numbers no longer
  2290 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  2291 le_def and less_def have disappeared.  Consider lemmas not_less
  2292 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  2293 
  2294 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  2295 (whose purpose mainly is for various fold_set functionals) have been
  2296 abandoned in favor of the existing algebraic classes
  2297 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  2298 lower_semilattice (resp. upper_semilattice) and linorder.
  2299 INCOMPATIBILITY.
  2300 
  2301 * Theory Transitive_Closure: induct and cases rules now declare proper
  2302 case_names ("base" and "step").  INCOMPATIBILITY.
  2303 
  2304 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  2305 lattices.  The form set-specific version is available as
  2306 Inductive.lfp_ordinal_induct_set.
  2307 
  2308 * Renamed theorems "power.simps" to "power_int.simps".
  2309 INCOMPATIBILITY.
  2310 
  2311 * Class semiring_div provides basic abstract properties of semirings
  2312 with division and modulo operations.  Subsumes former class dvd_mod.
  2313 
  2314 * Merged theories IntDef, Numeral and IntArith into unified theory
  2315 Int.  INCOMPATIBILITY.
  2316 
  2317 * Theory Library/Code_Index: type "index" now represents natural
  2318 numbers rather than integers.  INCOMPATIBILITY.
  2319 
  2320 * New class "uminus" with operation "uminus" (split of from class
  2321 "minus" which now only has operation "minus", binary).
  2322 INCOMPATIBILITY.
  2323 
  2324 * Constants "card", "internal_split", "option_map" now with authentic
  2325 syntax.  INCOMPATIBILITY.
  2326 
  2327 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  2328 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  2329 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  2330 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  2331 Sup_set_def, le_def, less_def, option_map_def now with object
  2332 equality.  INCOMPATIBILITY.
  2333 
  2334 * Records. Removed K_record, and replaced it by pure lambda term
  2335 %x. c. The simplifier setup is now more robust against eta expansion.
  2336 INCOMPATIBILITY: in cases explicitly referring to K_record.
  2337 
  2338 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  2339 
  2340 * Library/ListVector: new theory of arithmetic vector operations.
  2341 
  2342 * Library/Order_Relation: new theory of various orderings as sets of
  2343 pairs.  Defines preorders, partial orders, linear orders and
  2344 well-orders on sets and on types.
  2345 
  2346 
  2347 *** ZF ***
  2348 
  2349 * Renamed some theories to allow to loading both ZF and HOL in the
  2350 same session:
  2351 
  2352   Datatype  -> Datatype_ZF
  2353   Inductive -> Inductive_ZF
  2354   Int       -> Int_ZF
  2355   IntDiv    -> IntDiv_ZF
  2356   Nat       -> Nat_ZF
  2357   List      -> List_ZF
  2358   Main      -> Main_ZF
  2359 
  2360 INCOMPATIBILITY: ZF theories that import individual theories below
  2361 Main might need to be adapted.  Regular theory Main is still
  2362 available, as trivial extension of Main_ZF.
  2363 
  2364 
  2365 *** ML ***
  2366 
  2367 * ML within Isar: antiquotation @{const name} or @{const
  2368 name(typargs)} produces statically-checked Const term.
  2369 
  2370 * Functor NamedThmsFun: data is available to the user as dynamic fact
  2371 (of the same name).  Removed obsolete print command.
  2372 
  2373 * Removed obsolete "use_legacy_bindings" function.
  2374 
  2375 * The ``print mode'' is now a thread-local value derived from a global
  2376 template (the former print_mode reference), thus access becomes
  2377 non-critical.  The global print_mode reference is for session
  2378 management only; user-code should use print_mode_value,
  2379 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  2380 
  2381 * Functions system/system_out provide a robust way to invoke external
  2382 shell commands, with propagation of interrupts (requires Poly/ML
  2383 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  2384 
  2385 
  2386 *** System ***
  2387 
  2388 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  2389 in accordance with Proof General 3.7, which prefers GNU emacs.
  2390 
  2391 * isatool tty runs Isabelle process with plain tty interaction;
  2392 optional line editor may be specified via ISABELLE_LINE_EDITOR
  2393 setting, the default settings attempt to locate "ledit" and "rlwrap".
  2394 
  2395 * isatool browser now works with Cygwin as well, using general
  2396 "javapath" function defined in Isabelle process environment.
  2397 
  2398 * YXML notation provides a simple and efficient alternative to
  2399 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  2400 isatool yxml as described in the Isabelle system manual.
  2401 
  2402 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  2403 provides general wrapper for managing an Isabelle process in a robust
  2404 fashion, with ``cooked'' output from stdin/stderr.
  2405 
  2406 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  2407 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  2408 
  2409 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  2410 way of changing the user's settings is via
  2411 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  2412 script.
  2413 
  2414 * Multithreading.max_threads := 0 refers to the number of actual CPU
  2415 cores of the underlying machine, which is a good starting point for
  2416 optimal performance tuning.  The corresponding usedir option -M allows
  2417 "max" as an alias for "0".  WARNING: does not work on certain versions
  2418 of Mac OS (with Poly/ML 5.1).
  2419 
  2420 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  2421 adverse effect of Isabelle flooding interactive front-ends (notably
  2422 ProofGeneral / XEmacs).
  2423 
  2424 
  2425 
  2426 New in Isabelle2007 (November 2007)
  2427 -----------------------------------
  2428 
  2429 *** General ***
  2430 
  2431 * More uniform information about legacy features, notably a
  2432 warning/error of "Legacy feature: ...", depending on the state of the
  2433 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  2434 legacy features will disappear eventually.
  2435 
  2436 * Theory syntax: the header format ``theory A = B + C:'' has been
  2437 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  2438 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  2439 
  2440 * Theory syntax: the old non-Isar theory file format has been
  2441 discontinued altogether.  Note that ML proof scripts may still be used
  2442 with Isar theories; migration is usually quite simple with the ML
  2443 function use_legacy_bindings.  INCOMPATIBILITY.
  2444 
  2445 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  2446 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  2447 quotes.
  2448 
  2449 * Theory loader: be more serious about observing the static theory
  2450 header specifications (including optional directories), but not the
  2451 accidental file locations of previously successful loads.  The strict
  2452 update policy of former update_thy is now already performed by
  2453 use_thy, so the former has been removed; use_thys updates several
  2454 theories simultaneously, just as 'imports' within a theory header
  2455 specification, but without merging the results.  Potential
  2456 INCOMPATIBILITY: may need to refine theory headers and commands
  2457 ROOT.ML which depend on load order.
  2458 
  2459 * Theory loader: optional support for content-based file
  2460 identification, instead of the traditional scheme of full physical
  2461 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  2462 (cf. the system manual).  The new scheme allows to work with
  2463 non-finished theories in persistent session images, such that source
  2464 files may be moved later on without requiring reloads.
  2465 
  2466 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2467 file (with the same base name as the theory) are considered a legacy
  2468 feature, which will disappear eventually. Even now, the theory loader
  2469 no longer maintains dependencies on such files.
  2470 
  2471 * Syntax: the scope for resolving ambiguities via type-inference is
  2472 now limited to individual terms, instead of whole simultaneous
  2473 specifications as before. This greatly reduces the complexity of the
  2474 syntax module and improves flexibility by separating parsing and
  2475 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  2476 'fixes' etc.) are required in rare situations.
  2477 
  2478 * Syntax: constants introduced by new-style packages ('definition',
  2479 'abbreviation' etc.) are passed through the syntax module in
  2480 ``authentic mode''. This means that associated mixfix annotations
  2481 really stick to such constants, independently of potential name space
  2482 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  2483 trees are represented slightly differently, may need to adapt syntax
  2484 translations accordingly. Use CONST marker in 'translations' and
  2485 @{const_syntax} antiquotation in 'parse_translation' etc.
  2486 
  2487 * Legacy goal package: reduced interface to the bare minimum required
  2488 to keep existing proof scripts running.  Most other user-level
  2489 functions are now part of the OldGoals structure, which is *not* open
  2490 by default (consider isatool expandshort before open OldGoals).
  2491 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  2492 these tend to cause confusion about the actual goal (!) context being
  2493 used here, which is not necessarily the same as the_context().
  2494 
  2495 * Command 'find_theorems': supports "*" wild-card in "name:"
  2496 criterion; "with_dups" option.  Certain ProofGeneral versions might
  2497 support a specific search form (see ProofGeneral/CHANGES).
  2498 
  2499 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  2500 by default, which means that "prems" (and also "fixed variables") are
  2501 suppressed from proof state output.  Note that the ProofGeneral
  2502 settings mechanism allows to change and save options persistently, but
  2503 older versions of Isabelle will fail to start up if a negative prems
  2504 limit is imposed.
  2505 
  2506 * Local theory targets may be specified by non-nested blocks of
  2507 ``context/locale/class ... begin'' followed by ``end''.  The body may
  2508 contain definitions, theorems etc., including any derived mechanism
  2509 that has been implemented on top of these primitives.  This concept
  2510 generalizes the existing ``theorem (in ...)'' towards more versatility
  2511 and scalability.
  2512 
  2513 * Proof General interface: proper undo of final 'end' command;
  2514 discontinued Isabelle/classic mode (ML proof scripts).
  2515 
  2516 
  2517 *** Document preparation ***
  2518 
  2519 * Added antiquotation @{theory name} which prints the given name,
  2520 after checking that it refers to a valid ancestor theory in the
  2521 current context.
  2522 
  2523 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  2524 check the given source text as ML type/structure, printing verbatim.
  2525 
  2526 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  2527 "c args == rhs" given in the current context.  (Any number of
  2528 arguments may be given on the LHS.)
  2529 
  2530 
  2531 *** Pure ***
  2532 
  2533 * The 'class' package offers a combination of axclass and locale to
  2534 achieve Haskell-like type classes in Isabelle.  Definitions and
  2535 theorems within a class context produce both relative results (with
  2536 implicit parameters according to the locale context), and polymorphic
  2537 constants with qualified polymorphism (according to the class
  2538 context).  Within the body context of a 'class' target, a separate
  2539 syntax layer ("user space type system") takes care of converting
  2540 between global polymorphic consts and internal locale representation.
  2541 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  2542 "isatool doc classes" provides a tutorial.
  2543 
  2544 * Generic code generator framework allows to generate executable
  2545 code for ML and Haskell (including Isabelle classes).  A short usage
  2546 sketch:
  2547 
  2548     internal compilation:
  2549         export_code <list of constants (term syntax)> in SML
  2550     writing SML code to a file:
  2551         export_code <list of constants (term syntax)> in SML <filename>
  2552     writing OCaml code to a file:
  2553         export_code <list of constants (term syntax)> in OCaml <filename>
  2554     writing Haskell code to a bunch of files:
  2555         export_code <list of constants (term syntax)> in Haskell <filename>
  2556 
  2557     evaluating closed propositions to True/False using code generation:
  2558         method ``eval''
  2559 
  2560 Reasonable default setup of framework in HOL.
  2561 
  2562 Theorem attributs for selecting and transforming function equations theorems:
  2563 
  2564     [code fun]:        select a theorem as function equation for a specific constant
  2565     [code fun del]:    deselect a theorem as function equation for a specific constant
  2566     [code inline]:     select an equation theorem for unfolding (inlining) in place
  2567     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  2568 
  2569 User-defined serializations (target in {SML, OCaml, Haskell}):
  2570 
  2571     code_const <and-list of constants (term syntax)>
  2572       {(target) <and-list of const target syntax>}+
  2573 
  2574     code_type <and-list of type constructors>
  2575       {(target) <and-list of type target syntax>}+
  2576 
  2577     code_instance <and-list of instances>
  2578       {(target)}+
  2579         where instance ::= <type constructor> :: <class>
  2580 
  2581     code_class <and_list of classes>
  2582       {(target) <and-list of class target syntax>}+
  2583         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  2584 
  2585 code_instance and code_class only are effective to target Haskell.
  2586 
  2587 For example usage see src/HOL/ex/Codegenerator.thy and
  2588 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  2589 generation from Isabelle/HOL theories is available via "isatool doc
  2590 codegen".
  2591 
  2592 * Code generator: consts in 'consts_code' Isar commands are now
  2593 referred to by usual term syntax (including optional type
  2594 annotations).
  2595 
  2596 * Command 'no_translations' removes translation rules from theory
  2597 syntax.
  2598 
  2599 * Overloaded definitions are now actually checked for acyclic
  2600 dependencies.  The overloading scheme is slightly more general than
  2601 that of Haskell98, although Isabelle does not demand an exact
  2602 correspondence to type class and instance declarations.
  2603 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  2604 exotic versions of overloading -- at the discretion of the user!
  2605 
  2606 Polymorphic constants are represented via type arguments, i.e. the
  2607 instantiation that matches an instance against the most general
  2608 declaration given in the signature.  For example, with the declaration
  2609 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  2610 as c(nat).  Overloading is essentially simultaneous structural
  2611 recursion over such type arguments.  Incomplete specification patterns
  2612 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  2613 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  2614 Command 'print_theory' outputs the normalized system of recursive
  2615 equations, see section "definitions".
  2616 
  2617 * Configuration options are maintained within the theory or proof
  2618 context (with name and type bool/int/string), providing a very simple
  2619 interface to a poor-man's version of general context data.  Tools may
  2620 declare options in ML (e.g. using Attrib.config_int) and then refer to
  2621 these values using Config.get etc.  Users may change options via an
  2622 associated attribute of the same name.  This form of context
  2623 declaration works particularly well with commands 'declare' or
  2624 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  2625 very easy to avoid global references, which would not observe Isar
  2626 toplevel undo/redo and fail to work with multithreading.
  2627 
  2628 Various global ML references of Pure and HOL have been turned into
  2629 configuration options:
  2630 
  2631   Unify.search_bound		unify_search_bound
  2632   Unify.trace_bound		unify_trace_bound
  2633   Unify.trace_simp		unify_trace_simp
  2634   Unify.trace_types		unify_trace_types
  2635   Simplifier.simp_depth_limit	simp_depth_limit
  2636   Blast.depth_limit		blast_depth_limit
  2637   DatatypeProp.dtK		datatype_distinctness_limit
  2638   fast_arith_neq_limit  	fast_arith_neq_limit
  2639   fast_arith_split_limit	fast_arith_split_limit
  2640 
  2641 * Named collections of theorems may be easily installed as context
  2642 data using the functor NamedThmsFun (see also
  2643 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  2644 attributes; there is also a toplevel print command.  This facility is
  2645 just a common case of general context data, which is the preferred way
  2646 for anything more complex than just a list of facts in canonical
  2647 order.
  2648 
  2649 * Isar: command 'declaration' augments a local theory by generic
  2650 declaration functions written in ML.  This enables arbitrary content
  2651 being added to the context, depending on a morphism that tells the
  2652 difference of the original declaration context wrt. the application
  2653 context encountered later on.
  2654 
  2655 * Isar: proper interfaces for simplification procedures.  Command
  2656 'simproc_setup' declares named simprocs (with match patterns, and body
  2657 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  2658 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  2659 
  2660 * Isar: an extra pair of brackets around attribute declarations
  2661 abbreviates a theorem reference involving an internal dummy fact,
  2662 which will be ignored later --- only the effect of the attribute on
  2663 the background context will persist.  This form of in-place
  2664 declarations is particularly useful with commands like 'declare' and
  2665 'using', for example ``have A using [[simproc a]] by simp''.
  2666 
  2667 * Isar: method "assumption" (and implicit closing of subproofs) now
  2668 takes simple non-atomic goal assumptions into account: after applying
  2669 an assumption as a rule the resulting subgoals are solved by atomic
  2670 assumption steps.  This is particularly useful to finish 'obtain'
  2671 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  2672 without referring to the original premise "!!x. P x ==> thesis" in the
  2673 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  2674 more permissive.
  2675 
  2676 * Isar: implicit use of prems from the Isar proof context is
  2677 considered a legacy feature.  Common applications like ``have A .''
  2678 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  2679 referencing facts explicitly here improves readability and
  2680 maintainability of proof texts.
  2681 
  2682 * Isar: improper proof element 'guess' is like 'obtain', but derives
  2683 the obtained context from the course of reasoning!  For example:
  2684 
  2685   assume "EX x y. A x & B y"   -- "any previous fact"
  2686   then guess x and y by clarify
  2687 
  2688 This technique is potentially adventurous, depending on the facts and
  2689 proof tools being involved here.
  2690 
  2691 * Isar: known facts from the proof context may be specified as literal
  2692 propositions, using ASCII back-quote syntax.  This works wherever
  2693 named facts used to be allowed so far, in proof commands, proof
  2694 methods, attributes etc.  Literal facts are retrieved from the context
  2695 according to unification of type and term parameters.  For example,
  2696 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  2697 theorems in the current context, then these are valid literal facts:
  2698 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  2699 
  2700 There is also a proof method "fact" which does the same composition
  2701 for explicit goal states, e.g. the following proof texts coincide with
  2702 certain special cases of literal facts:
  2703 
  2704   have "A" by fact                 ==  note `A`
  2705   have "A ==> B" by fact           ==  note `A ==> B`
  2706   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  2707   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  2708 
  2709 * Isar: ":" (colon) is no longer a symbolic identifier character in
  2710 outer syntax.  Thus symbolic identifiers may be used without
  2711 additional white space in declarations like this: ``assume *: A''.
  2712 
  2713 * Isar: 'print_facts' prints all local facts of the current context,
  2714 both named and unnamed ones.
  2715 
  2716 * Isar: 'def' now admits simultaneous definitions, e.g.:
  2717 
  2718   def x == "t" and y == "u"
  2719 
  2720 * Isar: added command 'unfolding', which is structurally similar to
  2721 'using', but affects both the goal state and facts by unfolding given
  2722 rewrite rules.  Thus many occurrences of the 'unfold' method or
  2723 'unfolded' attribute may be replaced by first-class proof text.
  2724 
  2725 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  2726 and command 'unfolding' now all support object-level equalities
  2727 (potentially conditional).  The underlying notion of rewrite rule is
  2728 analogous to the 'rule_format' attribute, but *not* that of the
  2729 Simplifier (which is usually more generous).
  2730 
  2731 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  2732 premises of a theorem by n. Useful in conjunction with drule.
  2733 
  2734 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  2735 method expression within a sandbox consisting of the first N
  2736 sub-goals, which need to exist.  For example, ``simp_all [3]''
  2737 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  2738 simplifies all new goals that emerge from applying rule foo to the
  2739 originally first one.
  2740 
  2741 * Isar: schematic goals are no longer restricted to higher-order
  2742 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  2743 expected.
  2744 
  2745 * Isar: the conclusion of a long theorem statement is now either
  2746 'shows' (a simultaneous conjunction, as before), or 'obtains'
  2747 (essentially a disjunction of cases with local parameters and
  2748 assumptions).  The latter allows to express general elimination rules
  2749 adequately; in this notation common elimination rules look like this:
  2750 
  2751   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  2752     assumes "EX x. P x"
  2753     obtains x where "P x"
  2754 
  2755   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  2756     assumes "A & B"
  2757     obtains A and B
  2758 
  2759   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  2760     assumes "A | B"
  2761     obtains
  2762       A
  2763     | B
  2764 
  2765 The subsequent classical rules even refer to the formal "thesis"
  2766 explicitly:
  2767 
  2768   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  2769     obtains "~ thesis"
  2770 
  2771   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  2772     obtains "thesis ==> something"
  2773 
  2774 The actual proof of an 'obtains' statement is analogous to that of the
  2775 Isar proof element 'obtain', only that there may be several cases.
  2776 Optional case names may be specified in parentheses; these will be
  2777 available both in the present proof and as annotations in the
  2778 resulting rule, for later use with the 'cases' method (cf. attribute
  2779 case_names).
  2780 
  2781 * Isar: the assumptions of a long theorem statement are available as
  2782 "assms" fact in the proof context.  This is more appropriate than the
  2783 (historical) "prems", which refers to all assumptions of the current
  2784 context, including those from the target locale, proof body etc.
  2785 
  2786 * Isar: 'print_statement' prints theorems from the current theory or
  2787 proof context in long statement form, according to the syntax of a
  2788 top-level lemma.
  2789 
  2790 * Isar: 'obtain' takes an optional case name for the local context
  2791 introduction rule (default "that").
  2792 
  2793 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  2794 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  2795 to occur.
  2796 
  2797 * Pure: syntax "CONST name" produces a fully internalized constant
  2798 according to the current context.  This is particularly useful for
  2799 syntax translations that should refer to internal constant
  2800 representations independently of name spaces.
  2801 
  2802 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  2803 instead of "FOO ". This allows multiple binder declarations to coexist
  2804 in the same context.  INCOMPATIBILITY.
  2805 
  2806 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  2807 primitive that also works in a locale context (both for constants and
  2808 fixed variables). Type declaration and internal syntactic representation
  2809 of given constants retrieved from the context. Likewise, the
  2810 'no_notation' command allows to remove given syntax annotations from the
  2811 current context.
  2812 
  2813 * Isar/locales: new derived specification elements 'axiomatization',
  2814 'definition', 'abbreviation', which support type-inference, admit
  2815 object-level specifications (equality, equivalence).  See also the
  2816 isar-ref manual.  Examples:
  2817 
  2818   axiomatization
  2819     eq  (infix "===" 50) where
  2820     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  2821 
  2822   definition "f x y = x + y + 1"
  2823   definition g where "g x = f x x"
  2824 
  2825   abbreviation
  2826     neq  (infix "=!=" 50) where
  2827     "x =!= y == ~ (x === y)"
  2828 
  2829 These specifications may be also used in a locale context.  Then the
  2830 constants being introduced depend on certain fixed parameters, and the
  2831 constant name is qualified by the locale base name.  An internal
  2832 abbreviation takes care for convenient input and output, making the
  2833 parameters implicit and using the original short name.  See also
  2834 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  2835 entities from a monomorphic theory.
  2836 
  2837 Presently, abbreviations are only available 'in' a target locale, but
  2838 not inherited by general import expressions.  Also note that
  2839 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  2840 'translations' in common applications.  The "no_abbrevs" print mode
  2841 prevents folding of abbreviations in term output.
  2842 
  2843 Concrete syntax is attached to specified constants in internal form,
  2844 independently of name spaces.  The parse tree representation is
  2845 slightly different -- use 'notation' instead of raw 'syntax', and
  2846 'translations' with explicit "CONST" markup to accommodate this.
  2847 
  2848 * Pure/Isar: unified syntax for new-style specification mechanisms
  2849 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  2850 full type inference and dummy patterns ("_").  For example:
  2851 
  2852   definition "K x _ = x"
  2853 
  2854   inductive conj for A B
  2855   where "A ==> B ==> conj A B"
  2856 
  2857 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  2858 the current context.  Print mode "no_abbrevs" prevents inversion of
  2859 abbreviations on output.
  2860 
  2861 * Isar/locales: improved parameter handling: use of locales "var" and
  2862 "struct" no longer necessary; - parameter renamings are no longer
  2863 required to be injective.  For example, this allows to define
  2864 endomorphisms as locale endom = homom mult mult h.
  2865 
  2866 * Isar/locales: changed the way locales with predicates are defined.
  2867 Instead of accumulating the specification, the imported expression is
  2868 now an interpretation.  INCOMPATIBILITY: different normal form of
  2869 locale expressions.  In particular, in interpretations of locales with
  2870 predicates, goals repesenting already interpreted fragments are not
  2871 removed automatically.  Use methods `intro_locales' and
  2872 `unfold_locales'; see below.
  2873 
  2874 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  2875 provide backward reasoning on locales predicates.  The methods are
  2876 aware of interpretations and discharge corresponding goals.
  2877 `intro_locales' is less aggressive then `unfold_locales' and does not
  2878 unfold predicates to assumptions.
  2879 
  2880 * Isar/locales: the order in which locale fragments are accumulated
  2881 has changed.  This enables to override declarations from fragments due
  2882 to interpretations -- for example, unwanted simp rules.
  2883 
  2884 * Isar/locales: interpretation in theories and proof contexts has been
  2885 extended.  One may now specify (and prove) equations, which are
  2886 unfolded in interpreted theorems.  This is useful for replacing
  2887 defined concepts (constants depending on locale parameters) by
  2888 concepts already existing in the target context.  Example:
  2889 
  2890   interpretation partial_order ["op <= :: [int, int] => bool"]
  2891     where "partial_order.less (op <=) (x::int) y = (x < y)"
  2892 
  2893 Typically, the constant `partial_order.less' is created by a
  2894 definition specification element in the context of locale
  2895 partial_order.
  2896 
  2897 * Method "induct": improved internal context management to support
  2898 local fixes and defines on-the-fly. Thus explicit meta-level
  2899 connectives !!  and ==> are rarely required anymore in inductive goals
  2900 (using object-logic connectives for this purpose has been long
  2901 obsolete anyway). Common proof patterns are explained in
  2902 src/HOL/Induct/Common_Patterns.thy, see also
  2903 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  2904 examples.
  2905 
  2906 * Method "induct": improved handling of simultaneous goals. Instead of
  2907 introducing object-level conjunction, the statement is now split into
  2908 several conclusions, while the corresponding symbolic cases are nested
  2909 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  2910 see src/HOL/Induct/Common_Patterns.thy, for example.
  2911 
  2912 * Method "induct": mutual induction rules are now specified as a list
  2913 of rule sharing the same induction cases. HOL packages usually provide
  2914 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  2915 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  2916 mutual induction rules differently, i.e. like this:
  2917 
  2918   (induct rule: foo_bar.inducts)
  2919   (induct set: foo bar)
  2920   (induct pred: foo bar)
  2921   (induct type: foo bar)
  2922 
  2923 The ML function ProjectRule.projections turns old-style rules into the
  2924 new format.
  2925 
  2926 * Method "coinduct": dual of induction, see
  2927 src/HOL/Library/Coinductive_List.thy for various examples.
  2928 
  2929 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  2930 considered a legacy feature.
  2931 
  2932 * Attribute "symmetric" produces result with standardized schematic
  2933 variables (index 0).  Potential INCOMPATIBILITY.
  2934 
  2935 * Simplifier: by default the simplifier trace only shows top level
  2936 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  2937 default. Thus there is less danger of being flooded by the trace. The
  2938 trace indicates where parts have been suppressed.
  2939   
  2940 * Provers/classical: removed obsolete classical version of elim_format
  2941 attribute; classical elim/dest rules are now treated uniformly when
  2942 manipulating the claset.
  2943 
  2944 * Provers/classical: stricter checks to ensure that supplied intro,
  2945 dest and elim rules are well-formed; dest and elim rules must have at
  2946 least one premise.
  2947 
  2948 * Provers/classical: attributes dest/elim/intro take an optional
  2949 weight argument for the rule (just as the Pure versions).  Weights are
  2950 ignored by automated tools, but determine the search order of single
  2951 rule steps.
  2952 
  2953 * Syntax: input syntax now supports dummy variable binding "%_. b",
  2954 where the body does not mention the bound variable.  Note that dummy
  2955 patterns implicitly depend on their context of bounds, which makes
  2956 "{_. _}" match any set comprehension as expected.  Potential
  2957 INCOMPATIBILITY -- parse translations need to cope with syntactic
  2958 constant "_idtdummy" in the binding position.
  2959 
  2960 * Syntax: removed obsolete syntactic constant "_K" and its associated
  2961 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  2962 for example "A -> B" => "Pi A (%_. B)".
  2963 
  2964 * Pure: 'class_deps' command visualizes the subclass relation, using
  2965 the graph browser tool.
  2966 
  2967 * Pure: 'print_theory' now suppresses certain internal declarations by
  2968 default; use '!' option for full details.
  2969 
  2970 
  2971 *** HOL ***
  2972 
  2973 * Method "metis" proves goals by applying the Metis general-purpose
  2974 resolution prover (see also http://gilith.com/software/metis/).
  2975 Examples are in the directory MetisExamples.  WARNING: the
  2976 Isabelle/HOL-Metis integration does not yet work properly with
  2977 multi-threading.
  2978   
  2979 * Command 'sledgehammer' invokes external automatic theorem provers as
  2980 background processes.  It generates calls to the "metis" method if
  2981 successful. These can be pasted into the proof.  Users do not have to
  2982 wait for the automatic provers to return.  WARNING: does not really
  2983 work with multi-threading.
  2984 
  2985 * New "auto_quickcheck" feature tests outermost goal statements for
  2986 potential counter-examples.  Controlled by ML references
  2987 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  2988 5000 milliseconds).  Fails silently if statements is outside of
  2989 executable fragment, or any other codgenerator problem occurs.
  2990 
  2991 * New constant "undefined" with axiom "undefined x = undefined".
  2992 
  2993 * Added class "HOL.eq", allowing for code generation with polymorphic
  2994 equality.
  2995 
  2996 * Some renaming of class constants due to canonical name prefixing in
  2997 the new 'class' package:
  2998 
  2999     HOL.abs ~> HOL.abs_class.abs
  3000     HOL.divide ~> HOL.divide_class.divide
  3001     0 ~> HOL.zero_class.zero
  3002     1 ~> HOL.one_class.one
  3003     op + ~> HOL.plus_class.plus
  3004     op - ~> HOL.minus_class.minus
  3005     uminus ~> HOL.minus_class.uminus
  3006     op * ~> HOL.times_class.times
  3007     op < ~> HOL.ord_class.less
  3008     op <= > HOL.ord_class.less_eq
  3009     Nat.power ~> Power.power_class.power
  3010     Nat.size ~> Nat.size_class.size
  3011     Numeral.number_of ~> Numeral.number_class.number_of
  3012     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3013     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3014     Orderings.min ~> Orderings.ord_class.min
  3015     Orderings.max ~> Orderings.ord_class.max
  3016     Divides.op div ~> Divides.div_class.div
  3017     Divides.op mod ~> Divides.div_class.mod
  3018     Divides.op dvd ~> Divides.div_class.dvd
  3019 
  3020 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3021 
  3022 a) User-defined constants using any of the names "plus", "minus",
  3023 "times", "less" or "less_eq". The standard syntax translations for
  3024 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3025 names.
  3026 
  3027 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3028 INCOMPATIBILITY: use more specific names.
  3029 
  3030 c) Permutative equations (e.g. "a + b = b + a")
  3031 Since the change of names also changes the order of terms, permutative
  3032 rewrite rules may get applied in a different order. Experience shows
  3033 that this is rarely the case (only two adaptions in the whole Isabelle
  3034 distribution).  INCOMPATIBILITY: rewrite proofs
  3035 
  3036 d) ML code directly refering to constant names
  3037 This in general only affects hand-written proof tactics, simprocs and
  3038 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3039 Consider using @{const_name} antiquotation.
  3040 
  3041 * New class "default" with associated constant "default".
  3042 
  3043 * Function "sgn" is now overloaded and available on int, real, complex
  3044 (and other numeric types), using class "sgn".  Two possible defs of
  3045 sgn are given as equational assumptions in the classes sgn_if and
  3046 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3047 INCOMPATIBILITY.
  3048 
  3049 * Locale "partial_order" now unified with class "order" (cf. theory
  3050 Orderings), added parameter "less".  INCOMPATIBILITY.
  3051 
  3052 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3053 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3054 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3055 
  3056 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3057 changed order of proof goals in instance proofs.
  3058 
  3059 * The transitivity reasoner for partial and linear orders is set up
  3060 for classes "order" and "linorder".  Instances of the reasoner are available
  3061 in all contexts importing or interpreting the corresponding locales.
  3062 Method "order" invokes the reasoner separately; the reasoner
  3063 is also integrated with the Simplifier as a solver.  Diagnostic
  3064 command 'print_orders' shows the available instances of the reasoner
  3065 in the current context.
  3066 
  3067 * Localized monotonicity predicate in theory "Orderings"; integrated
  3068 lemmas max_of_mono and min_of_mono with this predicate.
  3069 INCOMPATIBILITY.
  3070 
  3071 * Formulation of theorem "dense" changed slightly due to integration
  3072 with new class dense_linear_order.
  3073 
  3074 * Uniform lattice theory development in HOL.
  3075 
  3076     constants "meet" and "join" now named "inf" and "sup"
  3077     constant "Meet" now named "Inf"
  3078 
  3079     classes "meet_semilorder" and "join_semilorder" now named
  3080       "lower_semilattice" and "upper_semilattice"
  3081     class "lorder" now named "lattice"
  3082     class "comp_lat" now named "complete_lattice"
  3083 
  3084     Instantiation of lattice classes allows explicit definitions
  3085     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3086 
  3087   INCOMPATIBILITY.  Theorem renames:
  3088 
  3089     meet_left_le            ~> inf_le1
  3090     meet_right_le           ~> inf_le2
  3091     join_left_le            ~> sup_ge1
  3092     join_right_le           ~> sup_ge2
  3093     meet_join_le            ~> inf_sup_ord
  3094     le_meetI                ~> le_infI
  3095     join_leI                ~> le_supI
  3096     le_meet                 ~> le_inf_iff
  3097     le_join                 ~> ge_sup_conv
  3098     meet_idempotent         ~> inf_idem
  3099     join_idempotent         ~> sup_idem
  3100     meet_comm               ~> inf_commute
  3101     join_comm               ~> sup_commute
  3102     meet_leI1               ~> le_infI1
  3103     meet_leI2               ~> le_infI2
  3104     le_joinI1               ~> le_supI1
  3105     le_joinI2               ~> le_supI2
  3106     meet_assoc              ~> inf_assoc
  3107     join_assoc              ~> sup_assoc
  3108     meet_left_comm          ~> inf_left_commute
  3109     meet_left_idempotent    ~> inf_left_idem
  3110     join_left_comm          ~> sup_left_commute
  3111     join_left_idempotent    ~> sup_left_idem
  3112     meet_aci                ~> inf_aci
  3113     join_aci                ~> sup_aci
  3114     le_def_meet             ~> le_iff_inf
  3115     le_def_join             ~> le_iff_sup
  3116     join_absorp2            ~> sup_absorb2
  3117     join_absorp1            ~> sup_absorb1
  3118     meet_absorp1            ~> inf_absorb1
  3119     meet_absorp2            ~> inf_absorb2
  3120     meet_join_absorp        ~> inf_sup_absorb
  3121     join_meet_absorp        ~> sup_inf_absorb
  3122     distrib_join_le         ~> distrib_sup_le
  3123     distrib_meet_le         ~> distrib_inf_le
  3124 
  3125     add_meet_distrib_left   ~> add_inf_distrib_left
  3126     add_join_distrib_left   ~> add_sup_distrib_left
  3127     is_join_neg_meet        ~> is_join_neg_inf
  3128     is_meet_neg_join        ~> is_meet_neg_sup
  3129     add_meet_distrib_right  ~> add_inf_distrib_right
  3130     add_join_distrib_right  ~> add_sup_distrib_right
  3131     add_meet_join_distribs  ~> add_sup_inf_distribs
  3132     join_eq_neg_meet        ~> sup_eq_neg_inf
  3133     meet_eq_neg_join        ~> inf_eq_neg_sup
  3134     add_eq_meet_join        ~> add_eq_inf_sup
  3135     meet_0_imp_0            ~> inf_0_imp_0
  3136     join_0_imp_0            ~> sup_0_imp_0
  3137     meet_0_eq_0             ~> inf_0_eq_0
  3138     join_0_eq_0             ~> sup_0_eq_0
  3139     neg_meet_eq_join        ~> neg_inf_eq_sup
  3140     neg_join_eq_meet        ~> neg_sup_eq_inf
  3141     join_eq_if              ~> sup_eq_if
  3142 
  3143     mono_meet               ~> mono_inf
  3144     mono_join               ~> mono_sup
  3145     meet_bool_eq            ~> inf_bool_eq
  3146     join_bool_eq            ~> sup_bool_eq
  3147     meet_fun_eq             ~> inf_fun_eq
  3148     join_fun_eq             ~> sup_fun_eq
  3149     meet_set_eq             ~> inf_set_eq
  3150     join_set_eq             ~> sup_set_eq
  3151     meet1_iff               ~> inf1_iff
  3152     meet2_iff               ~> inf2_iff
  3153     meet1I                  ~> inf1I
  3154     meet2I                  ~> inf2I
  3155     meet1D1                 ~> inf1D1
  3156     meet2D1                 ~> inf2D1
  3157     meet1D2                 ~> inf1D2
  3158     meet2D2                 ~> inf2D2
  3159     meet1E                  ~> inf1E
  3160     meet2E                  ~> inf2E
  3161     join1_iff               ~> sup1_iff
  3162     join2_iff               ~> sup2_iff
  3163     join1I1                 ~> sup1I1
  3164     join2I1                 ~> sup2I1
  3165     join1I1                 ~> sup1I1
  3166     join2I2                 ~> sup1I2
  3167     join1CI                 ~> sup1CI
  3168     join2CI                 ~> sup2CI
  3169     join1E                  ~> sup1E
  3170     join2E                  ~> sup2E
  3171 
  3172     is_meet_Meet            ~> is_meet_Inf
  3173     Meet_bool_def           ~> Inf_bool_def
  3174     Meet_fun_def            ~> Inf_fun_def
  3175     Meet_greatest           ~> Inf_greatest
  3176     Meet_lower              ~> Inf_lower
  3177     Meet_set_def            ~> Inf_set_def
  3178 
  3179     Sup_def                 ~> Sup_Inf
  3180     Sup_bool_eq             ~> Sup_bool_def
  3181     Sup_fun_eq              ~> Sup_fun_def
  3182     Sup_set_eq              ~> Sup_set_def
  3183 
  3184     listsp_meetI            ~> listsp_infI
  3185     listsp_meet_eq          ~> listsp_inf_eq
  3186 
  3187     meet_min                ~> inf_min
  3188     join_max                ~> sup_max
  3189 
  3190 * Added syntactic class "size"; overloaded constant "size" now has
  3191 type "'a::size ==> bool"
  3192 
  3193 * Internal reorganisation of `size' of datatypes: size theorems
  3194 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3195 simplification rules by default!); theorems "prod.size" now named
  3196 "*.size".
  3197 
  3198 * Class "div" now inherits from class "times" rather than "type".
  3199 INCOMPATIBILITY.
  3200 
  3201 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  3202 Linorder etc.  have disappeared; operations defined in terms of
  3203 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  3204 
  3205 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  3206 
  3207 * HOL-Word: New extensive library and type for generic, fixed size
  3208 machine words, with arithemtic, bit-wise, shifting and rotating
  3209 operations, reflection into int, nat, and bool lists, automation for
  3210 linear arithmetic (by automatic reflection into nat or int), including
  3211 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  3212 arithmetic type classes, supporting automatic simplification of
  3213 numerals on all operations.
  3214 
  3215 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  3216 
  3217 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  3218 
  3219 * Code generator library theories:
  3220   - Code_Integer represents HOL integers by big integer literals in target
  3221     languages.
  3222   - Code_Char represents HOL characters by character literals in target
  3223     languages.
  3224   - Code_Char_chr like Code_Char, but also offers treatment of character
  3225     codes; includes Code_Integer.
  3226   - Executable_Set allows to generate code for finite sets using lists.
  3227   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  3228     denominator).
  3229   - Executable_Real implements a subset of real numbers, namly those
  3230     representable by rational numbers.
  3231   - Efficient_Nat implements natural numbers by integers, which in general will
  3232     result in higher efficency; pattern matching with 0/Suc is eliminated;
  3233     includes Code_Integer.
  3234   - Code_Index provides an additional datatype index which is mapped to
  3235     target-language built-in integers.
  3236   - Code_Message provides an additional datatype message_string which is isomorphic to
  3237     strings; messages are mapped to target-language strings.
  3238 
  3239 * New package for inductive predicates
  3240 
  3241   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  3242 
  3243     inductive
  3244       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3245       for z_1 :: U_1 and ... and z_n :: U_m
  3246     where
  3247       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3248     | ...
  3249 
  3250   with full support for type-inference, rather than
  3251 
  3252     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3253 
  3254     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3255     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3256 
  3257     inductive "s z_1 ... z_m"
  3258     intros
  3259       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3260       ...
  3261 
  3262   For backward compatibility, there is a wrapper allowing inductive
  3263   sets to be defined with the new package via
  3264 
  3265     inductive_set
  3266       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3267       for z_1 :: U_1 and ... and z_n :: U_m
  3268     where
  3269       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3270     | ...
  3271 
  3272   or
  3273 
  3274     inductive_set
  3275       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3276       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3277       for z_1 :: U_1 and ... and z_n :: U_m
  3278     where
  3279       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3280     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3281     | ...
  3282 
  3283   if the additional syntax "p ..." is required.
  3284 
  3285   Numerous examples can be found in the subdirectories src/HOL/Auth,
  3286   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  3287 
  3288   INCOMPATIBILITIES:
  3289 
  3290   - Since declaration and definition of inductive sets or predicates
  3291     is no longer separated, abbreviations involving the newly
  3292     introduced sets or predicates must be specified together with the
  3293     introduction rules after the 'where' keyword (see above), rather
  3294     than before the actual inductive definition.
  3295 
  3296   - The variables in induction and elimination rules are now
  3297     quantified in the order of their occurrence in the introduction
  3298     rules, rather than in alphabetical order. Since this may break
  3299     some proofs, these proofs either have to be repaired, e.g. by
  3300     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  3301     statements of the form
  3302 
  3303       case (rule_i a_i_1 ... a_i_{k_i})
  3304 
  3305     or the old order of quantification has to be restored by explicitly adding
  3306     meta-level quantifiers in the introduction rules, i.e.
  3307 
  3308       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  3309 
  3310   - The format of the elimination rules is now
  3311 
  3312       p z_1 ... z_m x_1 ... x_n ==>
  3313         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3314         ==> ... ==> P
  3315 
  3316     for predicates and
  3317 
  3318       (x_1, ..., x_n) : s z_1 ... z_m ==>
  3319         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3320         ==> ... ==> P
  3321 
  3322     for sets rather than
  3323 
  3324       x : s z_1 ... z_m ==>
  3325         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  3326         ==> ... ==> P
  3327 
  3328     This may require terms in goals to be expanded to n-tuples
  3329     (e.g. using case_tac or simplification with the split_paired_all
  3330     rule) before the above elimination rule is applicable.
  3331 
  3332   - The elimination or case analysis rules for (mutually) inductive
  3333     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  3334     list of rules "p_1_..._p_k.elims" is no longer available.
  3335 
  3336 * New package "function"/"fun" for general recursive functions,
  3337 supporting mutual and nested recursion, definitions in local contexts,
  3338 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  3339 for small examples, and the separate tutorial on the function
  3340 package. The old recdef "package" is still available as before, but
  3341 users are encouraged to use the new package.
  3342 
  3343 * Method "lexicographic_order" automatically synthesizes termination
  3344 relations as lexicographic combinations of size measures. 
  3345 
  3346 * Case-expressions allow arbitrary constructor-patterns (including
  3347 "_") and take their order into account, like in functional
  3348 programming.  Internally, this is translated into nested
  3349 case-expressions; missing cases are added and mapped to the predefined
  3350 constant "undefined". In complicated cases printing may no longer show
  3351 the original input but the internal form. Lambda-abstractions allow
  3352 the same form of pattern matching: "% pat1 => e1 | ..." is an
  3353 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  3354 variable.
  3355 
  3356 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  3357 is an abbreviation for "of_nat :: nat => int". The simplification
  3358 rules for "of_nat" have been changed to work like "int" did
  3359 previously.  Potential INCOMPATIBILITY:
  3360   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  3361   - of_nat_diff and of_nat_mult are no longer default simp rules
  3362 
  3363 * Method "algebra" solves polynomial equations over (semi)rings using
  3364 Groebner bases. The (semi)ring structure is defined by locales and the
  3365 tool setup depends on that generic context. Installing the method for
  3366 a specific type involves instantiating the locale and possibly adding
  3367 declarations for computation on the coefficients.  The method is
  3368 already instantiated for natural numbers and for the axiomatic class
  3369 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  3370 CALCULEMUS 2007 for the general principles underlying this
  3371 architecture of context-aware proof-tools.
  3372 
  3373 * Method "ferrack" implements quantifier elimination over
  3374 special-purpose dense linear orders using locales (analogous to
  3375 "algebra"). The method is already installed for class
  3376 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  3377 rat, etc.
  3378 
  3379 * Former constant "List.op @" now named "List.append".  Use ML
  3380 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  3381 circumvent possible incompatibilities when working on ML level.
  3382 
  3383 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  3384 
  3385 * New function listsum :: 'a list => 'a for arbitrary monoids.
  3386 Special syntax: "SUM x <- xs. f x" (and latex variants)
  3387 
  3388 * New syntax for Haskell-like list comprehension (input only), eg.
  3389 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  3390 
  3391 * The special syntax for function "filter" has changed from [x :
  3392 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  3393 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  3394 
  3395 * [a..b] is now defined for arbitrary linear orders.  It used to be
  3396 defined on nat only, as an abbreviation for [a..<Suc b]
  3397 INCOMPATIBILITY.
  3398 
  3399 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  3400 
  3401 * New functions "sorted" and "sort" in src/HOL/List.thy.
  3402 
  3403 * New lemma collection field_simps (an extension of ring_simps) for
  3404 manipulating (in)equations involving division. Multiplies with all
  3405 denominators that can be proved to be non-zero (in equations) or
  3406 positive/negative (in inequations).
  3407 
  3408 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  3409 have been improved and renamed to ring_simps, group_simps and
  3410 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  3411 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  3412 
  3413 * Theory Library/Commutative_Ring: switched from recdef to function
  3414 package; constants add, mul, pow now curried.  Infix syntax for
  3415 algebraic operations.
  3416 
  3417 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  3418 INCOMPATIBILITY.
  3419 
  3420 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  3421 INCOMPATIBILITY.
  3422 
  3423 * HOL/records: generalised field-update to take a function on the
  3424 field rather than the new value: r(|A := x|) is translated to A_update
  3425 (K x) r The K-combinator that is internally used is called K_record.
  3426 INCOMPATIBILITY: Usage of the plain update functions has to be
  3427 adapted.
  3428  
  3429 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  3430 * x = 0, which are required for a semiring.  Richer structures do not
  3431 inherit from semiring_0 anymore, because this property is a theorem
  3432 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  3433 there is more to prove, but this is mostly trivial.
  3434 
  3435 * Class "recpower" is generalized to arbitrary monoids, not just
  3436 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  3437 commutativity or semiring properties additionally.
  3438 
  3439 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  3440 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  3441 better use 'abbreviation'.
  3442 
  3443 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  3444 
  3445 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  3446 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  3447 significant changes for setting up numeral syntax for types:
  3448   - New constants Numeral.pred and Numeral.succ instead
  3449       of former Numeral.bin_pred and Numeral.bin_succ.
  3450   - Use integer operations instead of bin_add, bin_mult and so on.
  3451   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  3452   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  3453 
  3454 See src/HOL/Integ/IntArith.thy for an example setup.
  3455 
  3456 * Command 'normal_form' computes the normal form of a term that may
  3457 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  3458 produces ``[b, c, a]'' (without proof).  This command is suitable for
  3459 heavy-duty computations because the functions are compiled to ML
  3460 first.  Correspondingly, a method "normalization" is provided.  See
  3461 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  3462 
  3463 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  3464 25 like -->); output depends on the "iff" print_mode, the default is
  3465 "A = B" (with priority 50).
  3466 
  3467 * Relations less (<) and less_eq (<=) are also available on type bool.
  3468 Modified syntax to disallow nesting without explicit parentheses,
  3469 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  3470 INCOMPATIBILITY.
  3471 
  3472 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  3473 
  3474 * Relation composition operator "op O" now has precedence 75 and binds
  3475 stronger than union and intersection. INCOMPATIBILITY.
  3476 
  3477 * The old set interval syntax "{m..n(}" (and relatives) has been
  3478 removed.  Use "{m..<n}" (and relatives) instead.
  3479 
  3480 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  3481 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  3482 ``declare [[simproc del: neq]]''.
  3483 
  3484 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  3485 True/False.
  3486 
  3487 * Theorem Cons_eq_map_conv no longer declared as "simp".
  3488 
  3489 * Theorem setsum_mult renamed to setsum_right_distrib.
  3490 
  3491 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  3492 ``rule'' method.
  3493 
  3494 * Reimplemented methods "sat" and "satx", with several improvements:
  3495 goals no longer need to be stated as "<prems> ==> False", equivalences
  3496 (i.e. "=" on type bool) are handled, variable names of the form
  3497 "lit_<n>" are no longer reserved, significant speedup.
  3498 
  3499 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  3500 zChaff is still supported as well.
  3501 
  3502 * 'inductive' and 'datatype': provide projections of mutual rules,
  3503 bundled as foo_bar.inducts;
  3504 
  3505 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  3506 Library.
  3507 
  3508 * Library: moved theory Accessible_Part to main HOL.
  3509 
  3510 * Library: added theory Coinductive_List of potentially infinite lists
  3511 as greatest fixed-point.
  3512 
  3513 * Library: added theory AssocList which implements (finite) maps as
  3514 association lists.
  3515 
  3516 * Method "evaluation" solves goals (i.e. a boolean expression)
  3517 efficiently by compiling it to ML.  The goal is "proved" (via an
  3518 oracle) if it evaluates to True.
  3519 
  3520 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  3521 also when invoked by the simplifier.  This results in the Simplifier
  3522 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  3523 Configuration option fast_arith_split_limit=0 recovers the old
  3524 behavior.
  3525 
  3526 * Support for hex (0x20) and binary (0b1001) numerals.
  3527 
  3528 * New method: reify eqs (t), where eqs are equations for an
  3529 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  3530 parameter, computes a term s::'b and a list xs::'a list and proves the
  3531 theorem I xs s = t. This is also known as reification or quoting. The
  3532 resulting theorem is applied to the subgoal to substitute t with I xs
  3533 s.  If t is omitted, the subgoal itself is reified.
  3534 
  3535 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  3536 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  3537 where f is supposed to be a computable function (in the sense of code
  3538 generattion). The method uses reify to compute s and xs as above then
  3539 applies corr_thm and uses normalization by evaluation to "prove" f s =
  3540 r and finally gets the theorem t = r, which is again applied to the
  3541 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  3542 
  3543 * Reflection: Automatic reification now handels binding, an example is
  3544 available in src/HOL/ex/ReflectionEx.thy
  3545 
  3546 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  3547 command 'statespace' that is similar to 'record', but introduces an
  3548 abstract specification based on the locale infrastructure instead of
  3549 HOL types.  This leads to extra flexibility in composing state spaces,
  3550 in particular multiple inheritance and renaming of components.
  3551 
  3552 
  3553 *** HOL-Complex ***
  3554 
  3555 * Hyperreal: Functions root and sqrt are now defined on negative real
  3556 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  3557 Nonnegativity side conditions have been removed from many lemmas, so
  3558 that more subgoals may now be solved by simplification; potential
  3559 INCOMPATIBILITY.
  3560 
  3561 * Real: new type classes formalize real normed vector spaces and
  3562 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  3563 and norm :: 'a => real.
  3564 
  3565 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  3566 reals into other types. The overloaded constant Reals :: 'a set is now
  3567 defined as range of_real; potential INCOMPATIBILITY.
  3568 
  3569 * Real: proper support for ML code generation, including 'quickcheck'.
  3570 Reals are implemented as arbitrary precision rationals.
  3571 
  3572 * Hyperreal: Several constants that previously worked only for the
  3573 reals have been generalized, so they now work over arbitrary vector
  3574 spaces. Type annotations may need to be added in some cases; potential
  3575 INCOMPATIBILITY.
  3576 
  3577   Infinitesimal  :: ('a::real_normed_vector) star set
  3578   HFinite        :: ('a::real_normed_vector) star set
  3579   HInfinite      :: ('a::real_normed_vector) star set
  3580   approx         :: ('a::real_normed_vector) star => 'a star => bool
  3581   monad          :: ('a::real_normed_vector) star => 'a star set
  3582   galaxy         :: ('a::real_normed_vector) star => 'a star set
  3583   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  3584   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  3585   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  3586   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  3587   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  3588   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  3589   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  3590   sgn            :: 'a::real_normed_vector => 'a
  3591   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  3592 
  3593 * Complex: Some complex-specific constants are now abbreviations for
  3594 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  3595 hnorm.  Other constants have been entirely removed in favor of the
  3596 polymorphic versions (INCOMPATIBILITY):
  3597 
  3598   approx        <-- capprox
  3599   HFinite       <-- CFinite
  3600   HInfinite     <-- CInfinite
  3601   Infinitesimal <-- CInfinitesimal
  3602   monad         <-- cmonad
  3603   galaxy        <-- cgalaxy
  3604   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  3605   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  3606   (ns)deriv     <-- (ns)cderiv
  3607 
  3608 
  3609 *** HOL-Algebra ***
  3610 
  3611 * Formalisation of ideals and the quotient construction over rings.
  3612 
  3613 * Order and lattice theory no longer based on records.
  3614 INCOMPATIBILITY.
  3615 
  3616 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  3617 greatest_closed.  INCOMPATIBILITY.
  3618 
  3619 * Method algebra is now set up via an attribute.  For examples see
  3620 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  3621 of algebraic structures.
  3622 
  3623 * Renamed theory CRing to Ring.
  3624 
  3625 
  3626 *** HOL-Nominal ***
  3627 
  3628 * Substantial, yet incomplete support for nominal datatypes (binding
  3629 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  3630 src/HOL/Nominal/Examples.  Prospective users should consult
  3631 http://isabelle.in.tum.de/nominal/
  3632 
  3633 
  3634 *** ML ***
  3635 
  3636 * ML basics: just one true type int, which coincides with IntInf.int
  3637 (even on SML/NJ).
  3638 
  3639 * ML within Isar: antiquotations allow to embed statically-checked
  3640 formal entities in the source, referring to the context available at
  3641 compile-time.  For example:
  3642 
  3643 ML {* @{sort "{zero,one}"} *}
  3644 ML {* @{typ "'a => 'b"} *}
  3645 ML {* @{term "%x. x"} *}
  3646 ML {* @{prop "x == y"} *}
  3647 ML {* @{ctyp "'a => 'b"} *}
  3648 ML {* @{cterm "%x. x"} *}
  3649 ML {* @{cprop "x == y"} *}
  3650 ML {* @{thm asm_rl} *}
  3651 ML {* @{thms asm_rl} *}
  3652 ML {* @{type_name c} *}
  3653 ML {* @{type_syntax c} *}
  3654 ML {* @{const_name c} *}
  3655 ML {* @{const_syntax c} *}
  3656 ML {* @{context} *}
  3657 ML {* @{theory} *}
  3658 ML {* @{theory Pure} *}
  3659 ML {* @{theory_ref} *}
  3660 ML {* @{theory_ref Pure} *}
  3661 ML {* @{simpset} *}
  3662 ML {* @{claset} *}
  3663 ML {* @{clasimpset} *}
  3664 
  3665 The same works for sources being ``used'' within an Isar context.
  3666 
  3667 * ML in Isar: improved error reporting; extra verbosity with
  3668 ML_Context.trace enabled.
  3669 
  3670 * Pure/General/table.ML: the join operations now works via exceptions
  3671 DUP/SAME instead of type option. This is simpler in simple cases, and
  3672 admits slightly more efficient complex applications.
  3673 
  3674 * Pure: 'advanced' translation functions (parse_translation etc.) now
  3675 use Context.generic instead of just theory.
  3676 
  3677 * Pure: datatype Context.generic joins theory/Proof.context and
  3678 provides some facilities for code that works in either kind of
  3679 context, notably GenericDataFun for uniform theory and proof data.
  3680 
  3681 * Pure: simplified internal attribute type, which is now always
  3682 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  3683 local (Proof.context) attributes have been discontinued, while
  3684 minimizing code duplication. Thm.rule_attribute and
  3685 Thm.declaration_attribute build canonical attributes; see also structure
  3686 Context for further operations on Context.generic, notably
  3687 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  3688 declarations and definitions.
  3689 
  3690 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  3691 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  3692 init only required for impure data. INCOMPATIBILITY: empty really need
  3693 to be empty (no dependencies on theory content!)
  3694 
  3695 * Pure/kernel: consts certification ignores sort constraints given in
  3696 signature declarations. (This information is not relevant to the
  3697 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  3698 potential INCOMPATIBILITY.
  3699 
  3700 * Pure: axiomatic type classes are now purely definitional, with
  3701 explicit proofs of class axioms and super class relations performed
  3702 internally. See Pure/axclass.ML for the main internal interfaces --
  3703 notably AxClass.define_class supercedes AxClass.add_axclass, and
  3704 AxClass.axiomatize_class/classrel/arity supersede
  3705 Sign.add_classes/classrel/arities.
  3706 
  3707 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  3708 global/local versions on theory vs. Proof.context have been
  3709 discontinued; Attrib.syntax and Method.syntax have been adapted
  3710 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  3711 attributes, methods, etc.
  3712 
  3713 * Pure: several functions of signature "... -> theory -> theory * ..."
  3714 have been reoriented to "... -> theory -> ... * theory" in order to
  3715 allow natural usage in combination with the ||>, ||>>, |-> and
  3716 fold_map combinators.
  3717 
  3718 * Pure: official theorem names (closed derivations) and additional
  3719 comments (tags) are now strictly separate.  Name hints -- which are
  3720 maintained as tags -- may be attached any time without affecting the
  3721 derivation.
  3722 
  3723 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  3724 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  3725 achieve the old behaviour.
  3726 
  3727 * Pure: the "Goal" constant is now called "prop", supporting a
  3728 slightly more general idea of ``protecting'' meta-level rule
  3729 statements.
  3730 
  3731 * Pure: Logic.(un)varify only works in a global context, which is now
  3732 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  3733 Logic.legacy_(un)varify as temporary workaround.
  3734 
  3735 * Pure: structure Name provides scalable operations for generating
  3736 internal variable names, notably Name.variants etc.  This replaces
  3737 some popular functions from term.ML:
  3738 
  3739   Term.variant		->  Name.variant
  3740   Term.variantlist	->  Name.variant_list
  3741   Term.invent_names	->  Name.invent_list
  3742 
  3743 Note that low-level renaming rarely occurs in new code -- operations
  3744 from structure Variable are used instead (see below).
  3745 
  3746 * Pure: structure Variable provides fundamental operations for proper
  3747 treatment of fixed/schematic variables in a context.  For example,
  3748 Variable.import introduces fixes for schematics of given facts and
  3749 Variable.export reverses the effect (up to renaming) -- this replaces
  3750 various freeze_thaw operations.
  3751 
  3752 * Pure: structure Goal provides simple interfaces for
  3753 init/conclude/finish and tactical prove operations (replacing former
  3754 Tactic.prove).  Goal.prove is the canonical way to prove results
  3755 within a given context; Goal.prove_global is a degraded version for
  3756 theory level goals, including a global Drule.standard.  Note that
  3757 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  3758 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  3759 in a locale context).
  3760 
  3761 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  3762 and type checking (Syntax.check_term etc.), with common combinations
  3763 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  3764 which are considered legacy and await removal.
  3765 
  3766 * Pure/Syntax: generic interfaces for type unchecking
  3767 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  3768 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  3769 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  3770 available for convenience, but refer to the very same operations using
  3771 a mere theory instead of a full context.
  3772 
  3773 * Isar: simplified treatment of user-level errors, using exception
  3774 ERROR of string uniformly.  Function error now merely raises ERROR,
  3775 without any side effect on output channels.  The Isar toplevel takes
  3776 care of proper display of ERROR exceptions.  ML code may use plain
  3777 handle/can/try; cat_error may be used to concatenate errors like this:
  3778 
  3779   ... handle ERROR msg => cat_error msg "..."
  3780 
  3781 Toplevel ML code (run directly or through the Isar toplevel) may be
  3782 embedded into the Isar toplevel with exception display/debug like
  3783 this:
  3784 
  3785   Isar.toplevel (fn () => ...)
  3786 
  3787 INCOMPATIBILITY, removed special transform_error facilities, removed
  3788 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  3789 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  3790 -- use plain ERROR instead.
  3791 
  3792 * Isar: theory setup now has type (theory -> theory), instead of a
  3793 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  3794 
  3795 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  3796 ProofContext.debug/verbose flags.
  3797 
  3798 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  3799 theory before entering a proof state.  Transactions now always see a
  3800 quasi-functional intermediate checkpoint, both in interactive and
  3801 batch mode.
  3802 
  3803 * Isar: simplified interfaces for outer syntax.  Renamed
  3804 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  3805 OuterSyntax.add_parsers -- this functionality is now included in
  3806 OuterSyntax.command etc.  INCOMPATIBILITY.
  3807 
  3808 * Simplifier: the simpset of a running simplification process now
  3809 contains a proof context (cf. Simplifier.the_context), which is the
  3810 very context that the initial simpset has been retrieved from (by
  3811 simpset_of/local_simpset_of).  Consequently, all plug-in components
  3812 (solver, looper etc.) may depend on arbitrary proof data.
  3813 
  3814 * Simplifier.inherit_context inherits the proof context (plus the
  3815 local bounds) of the current simplification process; any simproc
  3816 etc. that calls the Simplifier recursively should do this!  Removed
  3817 former Simplifier.inherit_bounds, which is already included here --
  3818 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  3819 specify an explicit context using Simplifier.context/theory_context.
  3820 
  3821 * Simplifier/Classical Reasoner: more abstract interfaces
  3822 change_simpset/claset for modifying the simpset/claset reference of a
  3823 theory; raw versions simpset/claset_ref etc. have been discontinued --
  3824 INCOMPATIBILITY.
  3825 
  3826 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  3827 "Trueprop" etc.
  3828 
  3829 
  3830 *** System ***
  3831 
  3832 * settings: the default heap location within ISABELLE_HOME_USER now
  3833 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  3834 Isabelle installations.
  3835 
  3836 * isabelle-process: option -S (secure mode) disables some critical
  3837 operations, notably runtime compilation and evaluation of ML source
  3838 code.
  3839 
  3840 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  3841 
  3842 * Support for parallel execution, using native multicore support of
  3843 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  3844 independent theories, according to the given theory header
  3845 specifications. The maximum number of worker threads is specified via
  3846 usedir option -M or the "max-threads" setting in Proof General. A
  3847 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  3848 to 6 on a 8-core machine.  User-code needs to observe certain
  3849 guidelines for thread-safe programming, see appendix A in the Isar
  3850 Implementation manual.
  3851 
  3852 
  3853 
  3854 New in Isabelle2005 (October 2005)
  3855 ----------------------------------
  3856 
  3857 *** General ***
  3858 
  3859 * Theory headers: the new header syntax for Isar theories is
  3860 
  3861   theory <name>
  3862   imports <theory1> ... <theoryN>
  3863   uses <file1> ... <fileM>
  3864   begin
  3865 
  3866 where the 'uses' part is optional.  The previous syntax
  3867 
  3868   theory <name> = <theory1> + ... + <theoryN>:
  3869 
  3870 will disappear in the next release.  Use isatool fixheaders to convert
  3871 existing theory files.  Note that there is no change in ancient
  3872 non-Isar theories now, but these will disappear soon.
  3873 
  3874 * Theory loader: parent theories can now also be referred to via
  3875 relative and absolute paths.
  3876 
  3877 * Command 'find_theorems' searches for a list of criteria instead of a
  3878 list of constants. Known criteria are: intro, elim, dest, name:string,
  3879 simp:term, and any term. Criteria can be preceded by '-' to select
  3880 theorems that do not match. Intro, elim, dest select theorems that
  3881 match the current goal, name:s selects theorems whose fully qualified
  3882 name contain s, and simp:term selects all simplification rules whose
  3883 lhs match term.  Any other term is interpreted as pattern and selects
  3884 all theorems matching the pattern. Available in ProofGeneral under
  3885 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  3886 
  3887   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  3888 
  3889 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  3890 matching the current goal as introduction rule and not having "HOL."
  3891 in their name (i.e. not being defined in theory HOL).
  3892 
  3893 * Command 'thms_containing' has been discontinued in favour of
  3894 'find_theorems'; INCOMPATIBILITY.
  3895 
  3896 * Communication with Proof General is now 8bit clean, which means that
  3897 Unicode text in UTF-8 encoding may be used within theory texts (both
  3898 formal and informal parts).  Cf. option -U of the Isabelle Proof
  3899 General interface.  Here are some simple examples (cf. src/HOL/ex):
  3900 
  3901   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  3902   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  3903 
  3904 * Improved efficiency of the Simplifier and, to a lesser degree, the
  3905 Classical Reasoner.  Typical big applications run around 2 times
  3906 faster.
  3907 
  3908 
  3909 *** Document preparation ***
  3910 
  3911 * Commands 'display_drafts' and 'print_drafts' perform simple output
  3912 of raw sources.  Only those symbols that do not require additional
  3913 LaTeX packages (depending on comments in isabellesym.sty) are
  3914 displayed properly, everything else is left verbatim.  isatool display
  3915 and isatool print are used as front ends (these are subject to the
  3916 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  3917 
  3918 * Command tags control specific markup of certain regions of text,
  3919 notably folding and hiding.  Predefined tags include "theory" (for
  3920 theory begin and end), "proof" for proof commands, and "ML" for
  3921 commands involving ML code; the additional tags "visible" and
  3922 "invisible" are unused by default.  Users may give explicit tag
  3923 specifications in the text, e.g. ''by %invisible (auto)''.  The
  3924 interpretation of tags is determined by the LaTeX job during document
  3925 preparation: see option -V of isatool usedir, or options -n and -t of
  3926 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  3927 \isadroptag.
  3928 
  3929 Several document versions may be produced at the same time via isatool
  3930 usedir (the generated index.html will link all of them).  Typical
  3931 specifications include ''-V document=theory,proof,ML'' to present
  3932 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  3933 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  3934 these parts without any formal replacement text.  The Isabelle site
  3935 default settings produce ''document'' and ''outline'' versions as
  3936 specified above.
  3937 
  3938 * Several new antiquotations:
  3939 
  3940   @{term_type term} prints a term with its type annotated;
  3941 
  3942   @{typeof term} prints the type of a term;
  3943 
  3944   @{const const} is the same as @{term const}, but checks that the
  3945   argument is a known logical constant;
  3946 
  3947   @{term_style style term} and @{thm_style style thm} print a term or
  3948   theorem applying a "style" to it
  3949 
  3950   @{ML text}
  3951 
  3952 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  3953 definitions, equations, inequations etc., 'concl' printing only the
  3954 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  3955 to print the specified premise.  TermStyle.add_style provides an ML
  3956 interface for introducing further styles.  See also the "LaTeX Sugar"
  3957 document practical applications.  The ML antiquotation prints
  3958 type-checked ML expressions verbatim.
  3959 
  3960 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  3961 and 'text' support optional locale specification '(in loc)', which
  3962 specifies the default context for interpreting antiquotations.  For
  3963 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  3964 
  3965 * Option 'locale=NAME' of antiquotations specifies an alternative
  3966 context interpreting the subsequent argument.  For example: @{thm
  3967 [locale=lattice] inf_assoc}.
  3968 
  3969 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  3970 a proof context.
  3971 
  3972 * Proper output of antiquotations for theory commands involving a
  3973 proof context (such as 'locale' or 'theorem (in loc) ...').
  3974 
  3975 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  3976 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  3977 
  3978 * isatool usedir: new option -C (default true) controls whether option
  3979 -D should include a copy of the original document directory; -C false
  3980 prevents unwanted effects such as copying of administrative CVS data.
  3981 
  3982 
  3983 *** Pure ***
  3984 
  3985 * Considerably improved version of 'constdefs' command.  Now performs
  3986 automatic type-inference of declared constants; additional support for
  3987 local structure declarations (cf. locales and HOL records), see also
  3988 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  3989 sequential dependencies of definitions within a single 'constdefs'
  3990 section; moreover, the declared name needs to be an identifier.  If
  3991 all fails, consider to fall back on 'consts' and 'defs' separately.
  3992 
  3993 * Improved indexed syntax and implicit structures.  First of all,
  3994 indexed syntax provides a notational device for subscripted
  3995 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  3996 expressions.  Secondly, in a local context with structure
  3997 declarations, number indexes \<^sub>n or the empty index (default
  3998 number 1) refer to a certain fixed variable implicitly; option
  3999 show_structs controls printing of implicit structures.  Typical
  4000 applications of these concepts involve record types and locales.
  4001 
  4002 * New command 'no_syntax' removes grammar declarations (and
  4003 translations) resulting from the given syntax specification, which is
  4004 interpreted in the same manner as for the 'syntax' command.
  4005 
  4006 * 'Advanced' translation functions (parse_translation etc.) may depend
  4007 on the signature of the theory context being presently used for
  4008 parsing/printing, see also isar-ref manual.
  4009 
  4010 * Improved 'oracle' command provides a type-safe interface to turn an
  4011 ML expression of type theory -> T -> term into a primitive rule of
  4012 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4013 is already included here); see also FOL/ex/IffExample.thy;
  4014 INCOMPATIBILITY.
  4015 
  4016 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4017 before); "cI" is no longer bound, use "c.intro" instead.
  4018 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4019 axclasses vs. locales.
  4020 
  4021 * Improved internal renaming of symbolic identifiers -- attach primes
  4022 instead of base 26 numbers.
  4023 
  4024 * New flag show_question_marks controls printing of leading question
  4025 marks in schematic variable names.
  4026 
  4027 * In schematic variable names, *any* symbol following \<^isub> or
  4028 \<^isup> is now treated as part of the base name.  For example, the
  4029 following works without printing of awkward ".0" indexes:
  4030 
  4031   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4032     by simp
  4033 
  4034 * Inner syntax includes (*(*nested*) comments*).
  4035 
  4036 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4037 annotations as "(00...)".
  4038 
  4039 * Clear separation of logical types and nonterminals, where the latter
  4040 may only occur in 'syntax' specifications or type abbreviations.
  4041 Before that distinction was only partially implemented via type class
  4042 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4043 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4044 exotic syntax specifications may require further adaption
  4045 (e.g. Cube/Cube.thy).
  4046 
  4047 * Removed obsolete type class "logic", use the top sort {} instead.
  4048 Note that non-logical types should be declared as 'nonterminals'
  4049 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4050 specifications.
  4051 
  4052 * Attributes 'induct' and 'cases': type or set names may now be
  4053 locally fixed variables as well.
  4054 
  4055 * Simplifier: can now control the depth to which conditional rewriting
  4056 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4057 Limit.
  4058 
  4059 * Simplifier: simplification procedures may now take the current
  4060 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4061 interface), which is very useful for calling the Simplifier
  4062 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4063 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4064 low-level mk_simproc no longer applies Logic.varify internally, to
  4065 allow for use in a context of fixed variables.
  4066 
  4067 * thin_tac now works even if the assumption being deleted contains !!
  4068 or ==>.  More generally, erule now works even if the major premise of
  4069 the elimination rule contains !! or ==>.
  4070 
  4071 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4072 
  4073 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4074 from Pure, which contains all common declarations already.  Both
  4075 theories are defined via plain Isabelle/Isar .thy files.
  4076 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4077 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4078 use isatool fixcpure to adapt your theory and ML sources.
  4079 
  4080 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4081 selections of theorems in named facts via index ranges.
  4082 
  4083 * 'print_theorems': in theory mode, really print the difference
  4084 wrt. the last state (works for interactive theory development only),
  4085 in proof mode print all local facts (cf. 'print_facts');
  4086 
  4087 * 'hide': option '(open)' hides only base names.
  4088 
  4089 * More efficient treatment of intermediate checkpoints in interactive
  4090 theory development.
  4091 
  4092 * Code generator is now invoked via code_module (incremental code
  4093 generation) and code_library (modular code generation, ML structures
  4094 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4095 must be quoted when used as identifiers.
  4096 
  4097 * New 'value' command for reading, evaluating and printing terms using
  4098 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4099 quoted when used as identifier.
  4100 
  4101 
  4102 *** Locales ***
  4103 
  4104 * New commands for the interpretation of locale expressions in
  4105 theories (1), locales (2) and proof contexts (3).  These generate
  4106 proof obligations from the expression specification.  After the
  4107 obligations have been discharged, theorems of the expression are added
  4108 to the theory, target locale or proof context.  The synopsis of the
  4109 commands is a follows:
  4110 
  4111   (1) interpretation expr inst
  4112   (2) interpretation target < expr
  4113   (3) interpret expr inst
  4114 
  4115 Interpretation in theories and proof contexts require a parameter
  4116 instantiation of terms from the current context.  This is applied to
  4117 specifications and theorems of the interpreted expression.
  4118 Interpretation in locales only permits parameter renaming through the
  4119 locale expression.  Interpretation is smart in that interpretations
  4120 that are active already do not occur in proof obligations, neither are
  4121 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4122 inspect active interpretations of a particular locale.  For details,
  4123 see the Isar Reference manual.  Examples can be found in
  4124 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4125 
  4126 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4127 'interpret' instead.
  4128 
  4129 * New context element 'constrains' for adding type constraints to
  4130 parameters.
  4131 
  4132 * Context expressions: renaming of parameters with syntax
  4133 redeclaration.
  4134 
  4135 * Locale declaration: 'includes' disallowed.
  4136 
  4137 * Proper static binding of attribute syntax -- i.e. types / terms /
  4138 facts mentioned as arguments are always those of the locale definition
  4139 context, independently of the context of later invocations.  Moreover,
  4140 locale operations (renaming and type / term instantiation) are applied
  4141 to attribute arguments as expected.
  4142 
  4143 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4144 actual attributes; rare situations may require Attrib.attribute to
  4145 embed those attributes into Attrib.src that lack concrete syntax.
  4146 Attribute implementations need to cooperate properly with the static
  4147 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4148 Attrib.XXX_thm etc. already do the right thing without further
  4149 intervention.  Only unusual applications -- such as "where" or "of"
  4150 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4151 on the context and the facts involved -- may have to assign parsed
  4152 values to argument tokens explicitly.
  4153 
  4154 * Changed parameter management in theorem generation for long goal
  4155 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4156 theorem statement in rare situations.
  4157 
  4158 * Locale inspection command 'print_locale' omits notes elements.  Use
  4159 'print_locale!' to have them included in the output.
  4160 
  4161 
  4162 *** Provers ***
  4163 
  4164 * Provers/hypsubst.ML: improved version of the subst method, for
  4165 single-step rewriting: it now works in bound variable contexts. New is
  4166 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4167 rewrite a different subterm than the original subst method, which is
  4168 still available as 'simplesubst'.
  4169 
  4170 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4171 and quasi orders.
  4172 
  4173 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4174 reflexive-transitive closure of relations.
  4175 
  4176 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4177 limit (previously hard-coded with a value of 20) user-definable.
  4178 
  4179 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4180 is peformed already.  Object-logics merely need to finish their
  4181 initial simpset configuration as before.  INCOMPATIBILITY.
  4182 
  4183 
  4184 *** HOL ***
  4185 
  4186 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4187 
  4188   syntax (epsilon)
  4189     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4190 
  4191 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4192 and x-symbol; use option '-m epsilon' to get it actually printed.
  4193 Moreover, the mathematically important symbolic identifier \<epsilon>
  4194 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4195 
  4196 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  4197 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  4198 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  4199 support corresponding Isar calculations.
  4200 
  4201 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  4202 instead of ":".
  4203 
  4204 * theory SetInterval: changed the syntax for open intervals:
  4205 
  4206   Old       New
  4207   {..n(}    {..<n}
  4208   {)n..}    {n<..}
  4209   {m..n(}   {m..<n}
  4210   {)m..n}   {m<..n}
  4211   {)m..n(}  {m<..<n}
  4212 
  4213 The old syntax is still supported but will disappear in the next
  4214 release.  For conversion use the following Emacs search and replace
  4215 patterns (these are not perfect but work quite well):
  4216 
  4217   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  4218   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  4219 
  4220 * Theory Commutative_Ring (in Library): method comm_ring for proving
  4221 equalities in commutative rings; method 'algebra' provides a generic
  4222 interface.
  4223 
  4224 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  4225 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  4226 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  4227 be a tuple pattern.
  4228 
  4229 Some new syntax forms are available:
  4230 
  4231   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  4232   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  4233   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  4234   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  4235 
  4236 The latter form "\<Sum>x < k. e" used to be based on a separate
  4237 function "Summation", which has been discontinued.
  4238 
  4239 * theory Finite_Set: in structured induction proofs, the insert case
  4240 is now 'case (insert x F)' instead of the old counterintuitive 'case
  4241 (insert F x)'.
  4242 
  4243 * The 'refute' command has been extended to support a much larger
  4244 fragment of HOL, including axiomatic type classes, constdefs and
  4245 typedefs, inductive datatypes and recursion.
  4246 
  4247 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  4248 Requires zChaff with proof generation to be installed.  See
  4249 HOL/ex/SAT_Examples.thy for examples.
  4250 
  4251 * Datatype induction via method 'induct' now preserves the name of the
  4252 induction variable. For example, when proving P(xs::'a list) by
  4253 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  4254 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  4255 in unstructured proof scripts.
  4256 
  4257 * Reworked implementation of records.  Improved scalability for
  4258 records with many fields, avoiding performance problems for type
  4259 inference. Records are no longer composed of nested field types, but
  4260 of nested extension types. Therefore the record type only grows linear
  4261 in the number of extensions and not in the number of fields.  The
  4262 top-level (users) view on records is preserved.  Potential
  4263 INCOMPATIBILITY only in strange cases, where the theory depends on the
  4264 old record representation. The type generated for a record is called
  4265 <record_name>_ext_type.
  4266 
  4267 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  4268 proofs triggered by a record definition or a simproc (if
  4269 quick_and_dirty is enabled).  Definitions of large records can take
  4270 quite long.
  4271 
  4272 New simproc record_upd_simproc for simplification of multiple record
  4273 updates enabled by default.  Moreover, trivial updates are also
  4274 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  4275 occasionally, since simplification is more powerful by default.
  4276 
  4277 * typedef: proper support for polymorphic sets, which contain extra
  4278 type-variables in the term.
  4279 
  4280 * Simplifier: automatically reasons about transitivity chains
  4281 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  4282 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  4283 old proofs break occasionally as simplification may now solve more
  4284 goals than previously.
  4285 
  4286 * Simplifier: converts x <= y into x = y if assumption y <= x is
  4287 present.  Works for all partial orders (class "order"), in particular
  4288 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  4289 just like y <= x.
  4290 
  4291 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  4292 bound variable or a constant then the let is unfolded.  Otherwise
  4293 first a is simplified to b, and then f b is simplified to g. If
  4294 possible we abstract b from g arriving at "let x = b in h x",
  4295 otherwise we unfold the let and arrive at g.  The simproc can be
  4296 enabled/disabled by the reference use_let_simproc.  Potential
  4297 INCOMPATIBILITY since simplification is more powerful by default.
  4298 
  4299 * Classical reasoning: the meson method now accepts theorems as arguments.
  4300 
  4301 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  4302 jobs to provide advice on the provability of subgoals.
  4303 
  4304 * Theory OrderedGroup and Ring_and_Field: various additions and
  4305 improvements to faciliate calculations involving equalities and
  4306 inequalities.
  4307 
  4308 The following theorems have been eliminated or modified
  4309 (INCOMPATIBILITY):
  4310 
  4311   abs_eq             now named abs_of_nonneg
  4312   abs_of_ge_0        now named abs_of_nonneg
  4313   abs_minus_eq       now named abs_of_nonpos
  4314   imp_abs_id         now named abs_of_nonneg
  4315   imp_abs_neg_id     now named abs_of_nonpos
  4316   mult_pos           now named mult_pos_pos
  4317   mult_pos_le        now named mult_nonneg_nonneg
  4318   mult_pos_neg_le    now named mult_nonneg_nonpos
  4319   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  4320   mult_neg           now named mult_neg_neg
  4321   mult_neg_le        now named mult_nonpos_nonpos
  4322 
  4323 * The following lemmas in Ring_and_Field have been added to the simplifier:
  4324      
  4325      zero_le_square
  4326      not_square_less_zero 
  4327 
  4328   The following lemmas have been deleted from Real/RealPow:
  4329   
  4330      realpow_zero_zero
  4331      realpow_two
  4332      realpow_less
  4333      zero_le_power
  4334      realpow_two_le
  4335      abs_realpow_two
  4336      realpow_two_abs     
  4337 
  4338 * Theory Parity: added rules for simplifying exponents.
  4339 
  4340 * Theory List:
  4341 
  4342 The following theorems have been eliminated or modified
  4343 (INCOMPATIBILITY):
  4344 
  4345   list_all_Nil       now named list_all.simps(1)
  4346   list_all_Cons      now named list_all.simps(2)
  4347   list_all_conv      now named list_all_iff
  4348   set_mem_eq         now named mem_iff
  4349 
  4350 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  4351 asymptotic "big O" calculations.  See the notes in BigO.thy.
  4352 
  4353 
  4354 *** HOL-Complex ***
  4355 
  4356 * Theory RealDef: better support for embedding natural numbers and
  4357 integers in the reals.
  4358 
  4359 The following theorems have been eliminated or modified
  4360 (INCOMPATIBILITY):
  4361 
  4362   exp_ge_add_one_self  now requires no hypotheses
  4363   real_of_int_add      reversed direction of equality (use [symmetric])
  4364   real_of_int_minus    reversed direction of equality (use [symmetric])
  4365   real_of_int_diff     reversed direction of equality (use [symmetric])
  4366   real_of_int_mult     reversed direction of equality (use [symmetric])
  4367 
  4368 * Theory RComplete: expanded support for floor and ceiling functions.
  4369 
  4370 * Theory Ln is new, with properties of the natural logarithm
  4371 
  4372 * Hyperreal: There is a new type constructor "star" for making
  4373 nonstandard types.  The old type names are now type synonyms:
  4374 
  4375   hypreal = real star
  4376   hypnat = nat star
  4377   hcomplex = complex star
  4378 
  4379 * Hyperreal: Many groups of similarly-defined constants have been
  4380 replaced by polymorphic versions (INCOMPATIBILITY):
  4381 
  4382   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  4383 
  4384   starset      <-- starsetNat, starsetC
  4385   *s*          <-- *sNat*, *sc*
  4386   starset_n    <-- starsetNat_n, starsetC_n
  4387   *sn*         <-- *sNatn*, *scn*
  4388   InternalSets <-- InternalNatSets, InternalCSets
  4389 
  4390   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  4391   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  4392   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  4393   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  4394   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  4395 
  4396 * Hyperreal: Many type-specific theorems have been removed in favor of
  4397 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  4398 
  4399   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  4400   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  4401   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  4402   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  4403   right_minus <-- hypreal_add_minus
  4404   left_minus <-- {hypreal,hcomplex}_add_minus_left
  4405   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  4406   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  4407   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  4408   mult_1_right <-- hcomplex_mult_one_right
  4409   mult_zero_left <-- hcomplex_mult_zero_left
  4410   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  4411   right_distrib <-- hypnat_add_mult_distrib2
  4412   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  4413   right_inverse <-- hypreal_mult_inverse
  4414   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  4415   order_refl <-- {hypreal,hypnat}_le_refl
  4416   order_trans <-- {hypreal,hypnat}_le_trans
  4417   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  4418   order_less_le <-- {hypreal,hypnat}_less_le
  4419   linorder_linear <-- {hypreal,hypnat}_le_linear
  4420   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  4421   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  4422   add_nonneg_nonneg <-- hypreal_le_add_order
  4423 
  4424 * Hyperreal: Separate theorems having to do with type-specific
  4425 versions of constants have been merged into theorems that apply to the
  4426 new polymorphic constants (INCOMPATIBILITY):
  4427 
  4428   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  4429   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  4430   STAR_Un <-- {STAR,NatStar,STARC}_Un
  4431   STAR_Int <-- {STAR,NatStar,STARC}_Int
  4432   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  4433   STAR_subset <-- {STAR,NatStar,STARC}_subset
  4434   STAR_mem <-- {STAR,NatStar,STARC}_mem
  4435   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  4436   STAR_diff <-- {STAR,STARC}_diff
  4437   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  4438     STARC_hcomplex_of_complex}_image_subset
  4439   starset_n_Un <-- starset{Nat,C}_n_Un
  4440   starset_n_Int <-- starset{Nat,C}_n_Int
  4441   starset_n_Compl <-- starset{Nat,C}_n_Compl
  4442   starset_n_diff <-- starset{Nat,C}_n_diff
  4443   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  4444   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  4445   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  4446   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  4447   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  4448   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  4449   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  4450   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  4451   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  4452   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  4453   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  4454   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  4455   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  4456   starfun_diff <-- starfun{C,RC,CR}_diff
  4457   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  4458   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  4459   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  4460   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  4461   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  4462   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  4463   starfun_Id <-- starfunC_Id
  4464   starfun_approx <-- starfun{Nat,CR}_approx
  4465   starfun_capprox <-- starfun{C,RC}_capprox
  4466   starfun_abs <-- starfunNat_rabs
  4467   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  4468   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  4469   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  4470   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  4471   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  4472   starfun_add_approx <-- starfunCR_add_approx
  4473   starfun_inverse_inverse <-- starfunC_inverse_inverse
  4474   starfun_divide <-- starfun{C,CR,RC}_divide
  4475   starfun_n <-- starfun{Nat,C}_n
  4476   starfun_n_mult <-- starfun{Nat,C}_n_mult
  4477   starfun_n_add <-- starfun{Nat,C}_n_add
  4478   starfun_n_add_minus <-- starfunNat_n_add_minus
  4479   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  4480   starfun_n_minus <-- starfun{Nat,C}_n_minus
  4481   starfun_n_eq <-- starfun{Nat,C}_n_eq
  4482 
  4483   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  4484   star_n_minus <-- {hypreal,hcomplex}_minus
  4485   star_n_diff <-- {hypreal,hcomplex}_diff
  4486   star_n_mult <-- {hypreal,hcomplex}_mult
  4487   star_n_inverse <-- {hypreal,hcomplex}_inverse
  4488   star_n_le <-- {hypreal,hypnat}_le
  4489   star_n_less <-- {hypreal,hypnat}_less
  4490   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  4491   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  4492   star_n_abs <-- hypreal_hrabs
  4493   star_n_divide <-- hcomplex_divide
  4494 
  4495   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  4496   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  4497   star_of_diff <-- hypreal_of_real_diff
  4498   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  4499   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  4500   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  4501   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  4502   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  4503   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  4504   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  4505   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  4506   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  4507   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  4508   star_of_number_of <-- {hypreal,hcomplex}_number_of
  4509   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  4510   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  4511   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  4512   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  4513   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  4514   star_of_power <-- hypreal_of_real_power
  4515   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  4516 
  4517 * Hyperreal: new method "transfer" that implements the transfer
  4518 principle of nonstandard analysis. With a subgoal that mentions
  4519 nonstandard types like "'a star", the command "apply transfer"
  4520 replaces it with an equivalent one that mentions only standard types.
  4521 To be successful, all free variables must have standard types; non-
  4522 standard variables must have explicit universal quantifiers.
  4523 
  4524 * Hyperreal: A theory of Taylor series.
  4525 
  4526 
  4527 *** HOLCF ***
  4528 
  4529 * Discontinued special version of 'constdefs' (which used to support
  4530 continuous functions) in favor of the general Pure one with full
  4531 type-inference.
  4532 
  4533 * New simplification procedure for solving continuity conditions; it
  4534 is much faster on terms with many nested lambda abstractions (cubic
  4535 instead of exponential time).
  4536 
  4537 * New syntax for domain package: selector names are now optional.
  4538 Parentheses should be omitted unless argument is lazy, for example:
  4539 
  4540   domain 'a stream = cons "'a" (lazy "'a stream")
  4541 
  4542 * New command 'fixrec' for defining recursive functions with pattern
  4543 matching; defining multiple functions with mutual recursion is also
  4544 supported.  Patterns may include the constants cpair, spair, up, sinl,
  4545 sinr, or any data constructor defined by the domain package. The given
  4546 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  4547 syntax and examples.
  4548 
  4549 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  4550 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  4551 but the proof obligation additionally includes an admissibility
  4552 requirement. The packages generate instances of class cpo or pcpo,
  4553 with continuity and strictness theorems for Rep and Abs.
  4554 
  4555 * HOLCF: Many theorems have been renamed according to a more standard naming
  4556 scheme (INCOMPATIBILITY):
  4557 
  4558   foo_inject:  "foo$x = foo$y ==> x = y"
  4559   foo_eq:      "(foo$x = foo$y) = (x = y)"
  4560   foo_less:    "(foo$x << foo$y) = (x << y)"
  4561   foo_strict:  "foo$UU = UU"
  4562   foo_defined: "... ==> foo$x ~= UU"
  4563   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  4564 
  4565 
  4566 *** ZF ***
  4567 
  4568 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  4569 including the First Isomorphism Theorem (on quotienting by the kernel
  4570 of a homomorphism).
  4571 
  4572 * ZF/Simplifier: install second copy of type solver that actually
  4573 makes use of TC rules declared to Isar proof contexts (or locales);
  4574 the old version is still required for ML proof scripts.
  4575 
  4576 
  4577 *** Cube ***
  4578 
  4579 * Converted to Isar theory format; use locales instead of axiomatic
  4580 theories.
  4581 
  4582 
  4583 *** ML ***
  4584 
  4585 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  4586 for ||>, ||>>, |>>,
  4587 
  4588 * Pure/library.ML no longer defines its own option datatype, but uses
  4589 that of the SML basis, which has constructors NONE and SOME instead of
  4590 None and Some, as well as exception Option.Option instead of OPTION.
  4591 The functions the, if_none, is_some, is_none have been adapted
  4592 accordingly, while Option.map replaces apsome.
  4593 
  4594 * Pure/library.ML: the exception LIST has been given up in favour of
  4595 the standard exceptions Empty and Subscript, as well as
  4596 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  4597 superceded by the standard hd and tl functions etc.
  4598 
  4599 A number of basic list functions are no longer exported to the ML
  4600 toplevel, as they are variants of predefined functions.  The following
  4601 suggests how one can translate existing code:
  4602 
  4603     rev_append xs ys = List.revAppend (xs, ys)
  4604     nth_elem (i, xs) = List.nth (xs, i)
  4605     last_elem xs = List.last xs
  4606     flat xss = List.concat xss
  4607     seq fs = List.app fs
  4608     partition P xs = List.partition P xs
  4609     mapfilter f xs = List.mapPartial f xs
  4610 
  4611 * Pure/library.ML: several combinators for linear functional
  4612 transformations, notably reverse application and composition:
  4613 
  4614   x |> f                f #> g
  4615   (x, y) |-> f          f #-> g
  4616 
  4617 * Pure/library.ML: introduced/changed precedence of infix operators:
  4618 
  4619   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  4620   infix 2 ?;
  4621   infix 3 o oo ooo oooo;
  4622   infix 4 ~~ upto downto;
  4623 
  4624 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  4625 infix operators.
  4626 
  4627 * Pure/library.ML: natural list combinators fold, fold_rev, and
  4628 fold_map support linear functional transformations and nesting.  For
  4629 example:
  4630 
  4631   fold f [x1, ..., xN] y =
  4632     y |> f x1 |> ... |> f xN
  4633 
  4634   (fold o fold) f [xs1, ..., xsN] y =
  4635     y |> fold f xs1 |> ... |> fold f xsN
  4636 
  4637   fold f [x1, ..., xN] =
  4638     f x1 #> ... #> f xN
  4639 
  4640   (fold o fold) f [xs1, ..., xsN] =
  4641     fold f xs1 #> ... #> fold f xsN
  4642 
  4643 * Pure/library.ML: the following selectors on type 'a option are
  4644 available:
  4645 
  4646   the:               'a option -> 'a  (*partial*)
  4647   these:             'a option -> 'a  where 'a = 'b list
  4648   the_default: 'a -> 'a option -> 'a
  4649   the_list:          'a option -> 'a list
  4650 
  4651 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  4652 basic operations for association lists, following natural argument
  4653 order; moreover the explicit equality predicate passed here avoids
  4654 potentially expensive polymorphic runtime equality checks.
  4655 The old functions may be expressed as follows:
  4656 
  4657   assoc = uncurry (AList.lookup (op =))
  4658   assocs = these oo AList.lookup (op =)
  4659   overwrite = uncurry (AList.update (op =)) o swap
  4660 
  4661 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  4662 
  4663   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  4664   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  4665 
  4666 replacing make_keylist and keyfilter (occassionally used)
  4667 Naive rewrites:
  4668 
  4669   make_keylist = AList.make
  4670   keyfilter = AList.find (op =)
  4671 
  4672 * eq_fst and eq_snd now take explicit equality parameter, thus
  4673   avoiding eqtypes. Naive rewrites:
  4674 
  4675     eq_fst = eq_fst (op =)
  4676     eq_snd = eq_snd (op =)
  4677 
  4678 * Removed deprecated apl and apr (rarely used).
  4679   Naive rewrites:
  4680 
  4681     apl (n, op) =>>= curry op n
  4682     apr (op, m) =>>= fn n => op (n, m)
  4683 
  4684 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  4685 provides a reasonably efficient light-weight implementation of sets as
  4686 lists.
  4687 
  4688 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  4689 few new operations; existing lookup and update are now curried to
  4690 follow natural argument order (for use with fold etc.);
  4691 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  4692 
  4693 * Pure/General: output via the Isabelle channels of
  4694 writeln/warning/error etc. is now passed through Output.output, with a
  4695 hook for arbitrary transformations depending on the print_mode
  4696 (cf. Output.add_mode -- the first active mode that provides a output
  4697 function wins).  Already formatted output may be embedded into further
  4698 text via Output.raw; the result of Pretty.string_of/str_of and derived
  4699 functions (string_of_term/cterm/thm etc.) is already marked raw to
  4700 accommodate easy composition of diagnostic messages etc.  Programmers
  4701 rarely need to care about Output.output or Output.raw at all, with
  4702 some notable exceptions: Output.output is required when bypassing the
  4703 standard channels (writeln etc.), or in token translations to produce
  4704 properly formatted results; Output.raw is required when capturing
  4705 already output material that will eventually be presented to the user
  4706 a second time.  For the default print mode, both Output.output and
  4707 Output.raw have no effect.
  4708 
  4709 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  4710 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  4711 cumulative results are displayed at the end of a batch session.
  4712 
  4713 * Pure/General: File.sysify_path and File.quote_sysify path have been
  4714 replaced by File.platform_path and File.shell_path (with appropriate
  4715 hooks).  This provides a clean interface for unusual systems where the
  4716 internal and external process view of file names are different.
  4717 
  4718 * Pure: more efficient orders for basic syntactic entities: added
  4719 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  4720 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  4721 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  4722 orders now -- potential INCOMPATIBILITY for code that depends on a
  4723 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  4724 Library.sort_strings on result).
  4725 
  4726 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  4727 fold_types traverse types/terms from left to right, observing natural
  4728 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  4729 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  4730 
  4731 * Pure: name spaces have been refined, with significant changes of the
  4732 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  4733 to extern(_table).  The plain name entry path is superceded by a
  4734 general 'naming' context, which also includes the 'policy' to produce
  4735 a fully qualified name and external accesses of a fully qualified
  4736 name; NameSpace.extend is superceded by context dependent
  4737 Sign.declare_name.  Several theory and proof context operations modify
  4738 the naming context.  Especially note Theory.restore_naming and
  4739 ProofContext.restore_naming to get back to a sane state; note that
  4740 Theory.add_path is no longer sufficient to recover from
  4741 Theory.absolute_path in particular.
  4742 
  4743 * Pure: new flags short_names (default false) and unique_names
  4744 (default true) for controlling output of qualified names.  If
  4745 short_names is set, names are printed unqualified.  If unique_names is
  4746 reset, the name prefix is reduced to the minimum required to achieve
  4747 the original result when interning again, even if there is an overlap
  4748 with earlier declarations.
  4749 
  4750 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  4751 now 'extend', and 'merge' gets an additional Pretty.pp argument
  4752 (useful for printing error messages).  INCOMPATIBILITY.
  4753 
  4754 * Pure: major reorganization of the theory context.  Type Sign.sg and
  4755 Theory.theory are now identified, referring to the universal
  4756 Context.theory (see Pure/context.ML).  Actual signature and theory
  4757 content is managed as theory data.  The old code and interfaces were
  4758 spread over many files and structures; the new arrangement introduces
  4759 considerable INCOMPATIBILITY to gain more clarity:
  4760 
  4761   Context -- theory management operations (name, identity, inclusion,
  4762     parents, ancestors, merge, etc.), plus generic theory data;
  4763 
  4764   Sign -- logical signature and syntax operations (declaring consts,
  4765     types, etc.), plus certify/read for common entities;
  4766 
  4767   Theory -- logical theory operations (stating axioms, definitions,
  4768     oracles), plus a copy of logical signature operations (consts,
  4769     types, etc.); also a few basic management operations (Theory.copy,
  4770     Theory.merge, etc.)
  4771 
  4772 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  4773 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  4774 for convenience -- they merely return the theory.
  4775 
  4776 * Pure: type Type.tsig is superceded by theory in most interfaces.
  4777 
  4778 * Pure: the Isar proof context type is already defined early in Pure
  4779 as Context.proof (note that ProofContext.context and Proof.context are
  4780 aliases, where the latter is the preferred name).  This enables other
  4781 Isabelle components to refer to that type even before Isar is present.
  4782 
  4783 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  4784 typeK, constK, axiomK, oracleK), but provide explicit operations for
  4785 any of these kinds.  For example, Sign.intern typeK is now
  4786 Sign.intern_type, Theory.hide_space Sign.typeK is now
  4787 Theory.hide_types.  Also note that former
  4788 Theory.hide_classes/types/consts are now
  4789 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  4790 internalize their arguments!  INCOMPATIBILITY.
  4791 
  4792 * Pure: get_thm interface (of PureThy and ProofContext) expects
  4793 datatype thmref (with constructors Name and NameSelection) instead of
  4794 plain string -- INCOMPATIBILITY;
  4795 
  4796 * Pure: cases produced by proof methods specify options, where NONE
  4797 means to remove case bindings -- INCOMPATIBILITY in
  4798 (RAW_)METHOD_CASES.
  4799 
  4800 * Pure: the following operations retrieve axioms or theorems from a
  4801 theory node or theory hierarchy, respectively:
  4802 
  4803   Theory.axioms_of: theory -> (string * term) list
  4804   Theory.all_axioms_of: theory -> (string * term) list
  4805   PureThy.thms_of: theory -> (string * thm) list
  4806   PureThy.all_thms_of: theory -> (string * thm) list
  4807 
  4808 * Pure: print_tac now outputs the goal through the trace channel.
  4809 
  4810 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  4811 Reference Toplevel.debug (default false) controls detailed printing
  4812 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  4813 controls execution profiling -- set to 1 for time and 2 for space
  4814 (both increase the runtime).
  4815 
  4816 * Isar session: The initial use of ROOT.ML is now always timed,
  4817 i.e. the log will show the actual process times, in contrast to the
  4818 elapsed wall-clock time that the outer shell wrapper produces.
  4819 
  4820 * Simplifier: improved handling of bound variables (nameless
  4821 representation, avoid allocating new strings).  Simprocs that invoke
  4822 the Simplifier recursively should use Simplifier.inherit_bounds to
  4823 avoid local name clashes.  Failure to do so produces warnings
  4824 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  4825 for further details.
  4826 
  4827 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  4828 bindings for all theorems stored within a given theory; this may help
  4829 in porting non-Isar theories to Isar ones, while keeping ML proof
  4830 scripts for the time being.
  4831 
  4832 * ML operator HTML.with_charset specifies the charset begin used for
  4833 generated HTML files.  For example:
  4834 
  4835   HTML.with_charset "utf-8" use_thy "Hebrew";
  4836   HTML.with_charset "utf-8" use_thy "Chinese";
  4837 
  4838 
  4839 *** System ***
  4840 
  4841 * Allow symlinks to all proper Isabelle executables (Isabelle,
  4842 isabelle, isatool etc.).
  4843 
  4844 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  4845 isatool doc, isatool mkdir, display_drafts etc.).
  4846 
  4847 * isatool usedir: option -f allows specification of the ML file to be
  4848 used by Isabelle; default is ROOT.ML.
  4849 
  4850 * New isatool version outputs the version identifier of the Isabelle
  4851 distribution being used.
  4852 
  4853 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  4854 (containing Boolean satisfiability problems) into Isabelle/HOL
  4855 theories.
  4856 
  4857 
  4858 
  4859 New in Isabelle2004 (April 2004)
  4860 --------------------------------
  4861 
  4862 *** General ***
  4863 
  4864 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  4865   Replaces linorder.ML.
  4866 
  4867 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  4868   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  4869   (\<a>...\<z>), are now considered normal letters, and can therefore
  4870   be used anywhere where an ASCII letter (a...zA...Z) has until
  4871   now. COMPATIBILITY: This obviously changes the parsing of some
  4872   terms, especially where a symbol has been used as a binder, say
  4873   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  4874   as an identifier.  Fix it by inserting a space around former
  4875   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  4876   existing theory and ML files.
  4877 
  4878 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  4879 
  4880 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  4881   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  4882   a normal (but invisible) letter. For multiple letter subscripts repeat
  4883   \<^isub> like this: x\<^isub>1\<^isub>2.
  4884 
  4885 * Pure: There are now sub-/superscripts that can span more than one
  4886   character. Text between \<^bsub> and \<^esub> is set in subscript in
  4887   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  4888   superscript. The new control characters are not identifier parts.
  4889 
  4890 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  4891   content of "..." to the latex file instead of \isacntrl... . The "..."
  4892   may consist of any printable characters excluding the end bracket >.
  4893 
  4894 * Pure: Using new Isar command "finalconsts" (or the ML functions
  4895   Theory.add_finals or Theory.add_finals_i) it is now possible to
  4896   declare constants "final", which prevents their being given a definition
  4897   later.  It is useful for constants whose behaviour is fixed axiomatically
  4898   rather than definitionally, such as the meta-logic connectives.
  4899 
  4900 * Pure: 'instance' now handles general arities with general sorts
  4901   (i.e. intersections of classes),
  4902 
  4903 * Presentation: generated HTML now uses a CSS style sheet to make layout
  4904   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  4905   It can be changed to alter the colors/layout of generated pages.
  4906 
  4907 
  4908 *** Isar ***
  4909 
  4910 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  4911   cut_tac, subgoal_tac and thin_tac:
  4912   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  4913     locales are no longer forced to write Isar proof scripts.
  4914     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  4915     emulations.
  4916   - INCOMPATIBILITY: names of variables to be instantiated may no
  4917     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  4918     This is consistent with the instantiation attribute "where".
  4919 
  4920 * Attributes "where" and "of":
  4921   - Now take type variables of instantiated theorem into account when reading
  4922     the instantiation string.  This fixes a bug that caused instantiated
  4923     theorems to have too special types in some circumstances.
  4924   - "where" permits explicit instantiations of type variables.
  4925 
  4926 * Calculation commands "moreover" and "also" no longer interfere with
  4927   current facts ("this"), admitting arbitrary combinations with "then"
  4928   and derived forms.
  4929 
  4930 * Locales:
  4931   - Goal statements involving the context element "includes" no longer
  4932     generate theorems with internal delta predicates (those ending on
  4933     "_axioms") in the premise.
  4934     Resolve particular premise with <locale>.intro to obtain old form.
  4935   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  4936     specification and "includes" elements in goal statement.
  4937   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  4938     [intro?] and [elim?] (respectively) by default.
  4939   - Experimental command for instantiation of locales in proof contexts:
  4940         instantiate <label>[<attrs>]: <loc>
  4941     Instantiates locale <loc> and adds all its theorems to the current context
  4942     taking into account their attributes.  Label and attrs are optional
  4943     modifiers, like in theorem declarations.  If present, names of
  4944     instantiated theorems are qualified with <label>, and the attributes
  4945     <attrs> are applied after any attributes these theorems might have already.
  4946       If the locale has assumptions, a chained fact of the form
  4947     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  4948     are derived.  The command does not support old-style locales declared
  4949     with "locale (open)".
  4950       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  4951 
  4952 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  4953   (Isar) contexts.
  4954 
  4955 
  4956 *** HOL ***
  4957 
  4958 * Proof import: new image HOL4 contains the imported library from
  4959   the HOL4 system with about 2500 theorems. It is imported by
  4960   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  4961   can be used like any other Isabelle image.  See
  4962   HOL/Import/HOL/README for more information.
  4963 
  4964 * Simplifier:
  4965   - Much improved handling of linear and partial orders.
  4966     Reasoners for linear and partial orders are set up for type classes
  4967     "linorder" and "order" respectively, and are added to the default simpset
  4968     as solvers.  This means that the simplifier can build transitivity chains
  4969     to solve goals from the assumptions.
  4970   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  4971     of blast or auto after simplification become unnecessary because the goal
  4972     is solved by simplification already.
  4973 
  4974 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  4975     all proved in axiomatic type classes for semirings, rings and fields.
  4976 
  4977 * Numerics:
  4978   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  4979     now formalized using the Ring_and_Field theory mentioned above.
  4980   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  4981     than before, because now they are set up once in a generic manner.
  4982   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  4983     Look for the general versions in Ring_and_Field (and Power if they concern
  4984     exponentiation).
  4985 
  4986 * Type "rat" of the rational numbers is now available in HOL-Complex.
  4987 
  4988 * Records:
  4989   - Record types are now by default printed with their type abbreviation
  4990     instead of the list of all field types. This can be configured via
  4991     the reference "print_record_type_abbr".
  4992   - Simproc "record_upd_simproc" for simplification of multiple updates added
  4993     (not enabled by default).
  4994   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  4995     EX x. x = sel r to True (not enabled by default).
  4996   - Tactic "record_split_simp_tac" to split and simplify records added.
  4997 
  4998 * 'specification' command added, allowing for definition by
  4999   specification.  There is also an 'ax_specification' command that
  5000   introduces the new constants axiomatically.
  5001 
  5002 * arith(_tac) is now able to generate counterexamples for reals as well.
  5003 
  5004 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5005 
  5006 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5007   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5008 
  5009 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5010   matrix theory to linear programming.
  5011 
  5012 * Unions and Intersections:
  5013   The latex output syntax of UN and INT has been changed
  5014   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5015   i.e. the index formulae has become a subscript.
  5016   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5017 
  5018 * Unions and Intersections over Intervals:
  5019   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5020   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5021   like in normal math, and corresponding versions for < and for intersection.
  5022 
  5023 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5024   lexicographic dictonary ordering has been added as "lexord".
  5025 
  5026 * ML: the legacy theory structures Int and List have been removed. They had
  5027   conflicted with ML Basis Library structures having the same names.
  5028 
  5029 * 'refute' command added to search for (finite) countermodels.  Only works
  5030   for a fragment of HOL.  The installation of an external SAT solver is
  5031   highly recommended.  See "HOL/Refute.thy" for details.
  5032 
  5033 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5034   formulae under an assignment of free variables to random values.
  5035   In contrast to 'refute', it can deal with inductive datatypes,
  5036   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5037   for examples.
  5038 
  5039 
  5040 *** HOLCF ***
  5041 
  5042 * Streams now come with concatenation and are part of the HOLCF image
  5043 
  5044 
  5045 
  5046 New in Isabelle2003 (May 2003)
  5047 ------------------------------
  5048 
  5049 *** General ***
  5050 
  5051 * Provers/simplifier:
  5052 
  5053   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5054     Assumptions are now subject to complete mutual simplification,
  5055     not just from left to right. The simplifier now preserves
  5056     the order of assumptions.
  5057 
  5058     Potential INCOMPATIBILITY:
  5059 
  5060     -- simp sometimes diverges where the old version did
  5061        not, e.g. invoking simp on the goal
  5062 
  5063         [| P (f x); y = x; f x = f y |] ==> Q
  5064 
  5065        now gives rise to the infinite reduction sequence
  5066 
  5067         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5068 
  5069        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5070        kind of problem.
  5071 
  5072     -- Tactics combining classical reasoner and simplification (such as auto)
  5073        are also affected by this change, because many of them rely on
  5074        simp. They may sometimes diverge as well or yield a different numbers
  5075        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5076        in case of problems. Sometimes subsequent calls to the classical
  5077        reasoner will fail because a preceeding call to the simplifier too
  5078        eagerly simplified the goal, e.g. deleted redundant premises.
  5079 
  5080   - The simplifier trace now shows the names of the applied rewrite rules
  5081 
  5082   - You can limit the number of recursive invocations of the simplifier
  5083     during conditional rewriting (where the simplifie tries to solve the
  5084     conditions before applying the rewrite rule):
  5085     ML "simp_depth_limit := n"
  5086     where n is an integer. Thus you can force termination where previously
  5087     the simplifier would diverge.
  5088 
  5089   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5090 
  5091   - No longer aborts on failed congruence proof.  Instead, the
  5092     congruence is ignored.
  5093 
  5094 * Pure: New generic framework for extracting programs from constructive
  5095   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5096   as HOL/Extraction for some case studies.
  5097 
  5098 * Pure: The main goal of the proof state is no longer shown by default, only
  5099 the subgoals. This behaviour is controlled by a new flag.
  5100    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5101 (ML: Proof.show_main_goal).
  5102 
  5103 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5104 rules whose conclusion matches subgoal 1:
  5105       PG menu: Isabelle/Isar -> Show me -> matching rules
  5106 The rules are ordered by how closely they match the subgoal.
  5107 In particular, rules that solve a subgoal outright are displayed first
  5108 (or rather last, the way they are printed).
  5109 (ML: ProofGeneral.print_intros())
  5110 
  5111 * Pure: New flag trace_unify_fail causes unification to print
  5112 diagnostic information (PG: in trace buffer) when it fails. This is
  5113 useful for figuring out why single step proofs like rule, erule or
  5114 assumption failed.
  5115 
  5116 * Pure: Locale specifications now produce predicate definitions
  5117 according to the body of text (covering assumptions modulo local
  5118 definitions); predicate "loc_axioms" covers newly introduced text,
  5119 while "loc" is cumulative wrt. all included locale expressions; the
  5120 latter view is presented only on export into the global theory
  5121 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5122 on the old view without predicates;
  5123 
  5124 * Pure: predefined locales "var" and "struct" are useful for sharing
  5125 parameters (as in CASL, for example); just specify something like
  5126 ``var x + var y + struct M'' as import;
  5127 
  5128 * Pure: improved thms_containing: proper indexing of facts instead of
  5129 raw theorems; check validity of results wrt. current name space;
  5130 include local facts of proof configuration (also covers active
  5131 locales), cover fixed variables in index; may use "_" in term
  5132 specification; an optional limit for the number of printed facts may
  5133 be given (the default is 40);
  5134 
  5135 * Pure: disallow duplicate fact bindings within new-style theory files
  5136 (batch-mode only);
  5137 
  5138 * Provers: improved induct method: assumptions introduced by case
  5139 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5140 the goal statement); "foo" still refers to all facts collectively;
  5141 
  5142 * Provers: the function blast.overloaded has been removed: all constants
  5143 are regarded as potentially overloaded, which improves robustness in exchange
  5144 for slight decrease in efficiency;
  5145 
  5146 * Provers/linorder: New generic prover for transitivity reasoning over
  5147 linear orders.  Note: this prover is not efficient!
  5148 
  5149 * Isar: preview of problems to finish 'show' now produce an error
  5150 rather than just a warning (in interactive mode);
  5151 
  5152 
  5153 *** HOL ***
  5154 
  5155 * arith(_tac)
  5156 
  5157  - Produces a counter example if it cannot prove a goal.
  5158    Note that the counter example may be spurious if the goal is not a formula
  5159    of quantifier-free linear arithmetic.
  5160    In ProofGeneral the counter example appears in the trace buffer.
  5161 
  5162  - Knows about div k and mod k where k is a numeral of type nat or int.
  5163 
  5164  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5165    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5166    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5167 
  5168 * simp's arithmetic capabilities have been enhanced a bit: it now
  5169 takes ~= in premises into account (by performing a case split);
  5170 
  5171 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5172 are distributed over a sum of terms;
  5173 
  5174 * New tactic "trans_tac" and method "trans" instantiate
  5175 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5176 "<=", "<" and "=").
  5177 
  5178 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5179 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5180 
  5181 * 'typedef' command has new option "open" to suppress the set
  5182 definition;
  5183 
  5184 * functions Min and Max on finite sets have been introduced (theory
  5185 Finite_Set);
  5186 
  5187 * attribute [symmetric] now works for relations as well; it turns
  5188 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5189 
  5190 * induct over a !!-quantified statement (say !!x1..xn):
  5191   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5192 
  5193 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5194 %x. None. Warning: empty_def now refers to the previously hidden definition
  5195 of the empty set.
  5196 
  5197 * Algebra: formalization of classical algebra.  Intended as base for
  5198 any algebraic development in Isabelle.  Currently covers group theory
  5199 (up to Sylow's theorem) and ring theory (Universal Property of
  5200 Univariate Polynomials).  Contributions welcome;
  5201 
  5202 * GroupTheory: deleted, since its material has been moved to Algebra;
  5203 
  5204 * Complex: new directory of the complex numbers with numeric constants,
  5205 nonstandard complex numbers, and some complex analysis, standard and
  5206 nonstandard (Jacques Fleuriot);
  5207 
  5208 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  5209 
  5210 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  5211 Fleuriot);
  5212 
  5213 * Real/HahnBanach: updated and adapted to locales;
  5214 
  5215 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  5216 Gray and Kramer);
  5217 
  5218 * UNITY: added the Meier-Sanders theory of progress sets;
  5219 
  5220 * MicroJava: bytecode verifier and lightweight bytecode verifier
  5221 as abstract algorithms, instantiated to the JVM;
  5222 
  5223 * Bali: Java source language formalization. Type system, operational
  5224 semantics, axiomatic semantics. Supported language features:
  5225 classes, interfaces, objects,virtual methods, static methods,
  5226 static/instance fields, arrays, access modifiers, definite
  5227 assignment, exceptions.
  5228 
  5229 
  5230 *** ZF ***
  5231 
  5232 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  5233 universe, etc.);
  5234 
  5235 * Main ZF: virtually all theories converted to new-style format;
  5236 
  5237 
  5238 *** ML ***
  5239 
  5240 * Pure: Tactic.prove provides sane interface for internal proofs;
  5241 omits the infamous "standard" operation, so this is more appropriate
  5242 than prove_goalw_cterm in many situations (e.g. in simprocs);
  5243 
  5244 * Pure: improved error reporting of simprocs;
  5245 
  5246 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  5247 up simprocs;
  5248 
  5249 
  5250 *** Document preparation ***
  5251 
  5252 * uses \par instead of \\ for line breaks in theory text. This may
  5253 shift some page breaks in large documents. To get the old behaviour
  5254 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  5255 
  5256 * minimized dependencies of isabelle.sty and isabellesym.sty on
  5257 other packages
  5258 
  5259 * \<euro> now needs package babel/greek instead of marvosym (which
  5260 broke \Rightarrow)
  5261 
  5262 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  5263 textcomp package)
  5264 
  5265 
  5266 
  5267 New in Isabelle2002 (March 2002)
  5268 --------------------------------
  5269 
  5270 *** Document preparation ***
  5271 
  5272 * greatly simplified document preparation setup, including more
  5273 graceful interpretation of isatool usedir -i/-d/-D options, and more
  5274 instructive isatool mkdir; users should basically be able to get
  5275 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  5276 users may run a separate document processing stage manually like this:
  5277 "isatool usedir -D output HOL Test && isatool document Test/output";
  5278 
  5279 * theory dependency graph may now be incorporated into documents;
  5280 isatool usedir -g true will produce session_graph.eps/.pdf for use
  5281 with \includegraphics of LaTeX;
  5282 
  5283 * proper spacing of consecutive markup elements, especially text
  5284 blocks after section headings;
  5285 
  5286 * support bold style (for single symbols only), input syntax is like
  5287 this: "\<^bold>\<alpha>" or "\<^bold>A";
  5288 
  5289 * \<bullet> is now output as bold \cdot by default, which looks much
  5290 better in printed text;
  5291 
  5292 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  5293 note that these symbols are currently unavailable in Proof General /
  5294 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  5295 
  5296 * isatool latex no longer depends on changed TEXINPUTS, instead
  5297 isatool document copies the Isabelle style files to the target
  5298 location;
  5299 
  5300 
  5301 *** Isar ***
  5302 
  5303 * Pure/Provers: improved proof by cases and induction;
  5304   - 'case' command admits impromptu naming of parameters (such as
  5305     "case (Suc n)");
  5306   - 'induct' method divinates rule instantiation from the inductive
  5307     claim; no longer requires excessive ?P bindings for proper
  5308     instantiation of cases;
  5309   - 'induct' method properly enumerates all possibilities of set/type
  5310     rules; as a consequence facts may be also passed through *type*
  5311     rules without further ado;
  5312   - 'induct' method now derives symbolic cases from the *rulified*
  5313     rule (before it used to rulify cases stemming from the internal
  5314     atomized version); this means that the context of a non-atomic
  5315     statement becomes is included in the hypothesis, avoiding the
  5316     slightly cumbersome show "PROP ?case" form;
  5317   - 'induct' may now use elim-style induction rules without chaining
  5318     facts, using ``missing'' premises from the goal state; this allows
  5319     rules stemming from inductive sets to be applied in unstructured
  5320     scripts, while still benefitting from proper handling of non-atomic
  5321     statements; NB: major inductive premises need to be put first, all
  5322     the rest of the goal is passed through the induction;
  5323   - 'induct' proper support for mutual induction involving non-atomic
  5324     rule statements (uses the new concept of simultaneous goals, see
  5325     below);
  5326   - append all possible rule selections, but only use the first
  5327     success (no backtracking);
  5328   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  5329   - undeclared rule case names default to numbers 1, 2, 3, ...;
  5330   - added 'print_induct_rules' (covered by help item in recent Proof
  5331     General versions);
  5332   - moved induct/cases attributes to Pure, methods to Provers;
  5333   - generic method setup instantiated for FOL and HOL;
  5334 
  5335 * Pure: support multiple simultaneous goal statements, for example
  5336 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  5337 meta-level mechanism, this acts as if several individual goals had
  5338 been stated separately; in particular common proof methods need to be
  5339 repeated in order to cover all claims; note that a single elimination
  5340 step is *not* sufficient to establish the two conjunctions, so this
  5341 fails:
  5342 
  5343   assume "A & B" then have A and B ..   (*".." fails*)
  5344 
  5345 better use "obtain" in situations as above; alternative refer to
  5346 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  5347 
  5348 * Pure: proper integration with ``locales''; unlike the original
  5349 version by Florian Kammller, Isar locales package high-level proof
  5350 contexts rather than raw logical ones (e.g. we admit to include
  5351 attributes everywhere); operations on locales include merge and
  5352 rename; support for implicit arguments (``structures''); simultaneous
  5353 type-inference over imports and text; see also HOL/ex/Locales.thy for
  5354 some examples;
  5355 
  5356 * Pure: the following commands have been ``localized'', supporting a
  5357 target locale specification "(in name)": 'lemma', 'theorem',
  5358 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  5359 stored both within the locale and at the theory level (exported and
  5360 qualified by the locale name);
  5361 
  5362 * Pure: theory goals may now be specified in ``long'' form, with
  5363 ad-hoc contexts consisting of arbitrary locale elements. for example
  5364 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  5365 definitions may be given, too); the result is a meta-level rule with
  5366 the context elements being discharged in the obvious way;
  5367 
  5368 * Pure: new proof command 'using' allows to augment currently used
  5369 facts after a goal statement ('using' is syntactically analogous to
  5370 'apply', but acts on the goal's facts only); this allows chained facts
  5371 to be separated into parts given before and after a claim, as in
  5372 ``from a and b have C using d and e <proof>'';
  5373 
  5374 * Pure: renamed "antecedent" case to "rule_context";
  5375 
  5376 * Pure: new 'judgment' command records explicit information about the
  5377 object-logic embedding (used by several tools internally); no longer
  5378 use hard-wired "Trueprop";
  5379 
  5380 * Pure: added 'corollary' command;
  5381 
  5382 * Pure: fixed 'token_translation' command;
  5383 
  5384 * Pure: removed obsolete 'exported' attribute;
  5385 
  5386 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  5387 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  5388 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  5389 
  5390 * Pure: method 'atomize' presents local goal premises as object-level
  5391 statements (atomic meta-level propositions); setup controlled via
  5392 rewrite rules declarations of 'atomize' attribute; example
  5393 application: 'induct' method with proper rule statements in improper
  5394 proof *scripts*;
  5395 
  5396 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  5397 now consider the syntactic context of assumptions, giving a better
  5398 chance to get type-inference of the arguments right (this is
  5399 especially important for locales);
  5400 
  5401 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  5402 mode;
  5403 
  5404 * Pure/obtain: the formal conclusion "thesis", being marked as
  5405 ``internal'', may no longer be reference directly in the text;
  5406 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  5407 situations;
  5408 
  5409 * Pure: generic 'sym' attribute which declares a rule both as pure
  5410 'elim?' and for the 'symmetric' operation;
  5411 
  5412 * Pure: marginal comments ``--'' may now occur just anywhere in the
  5413 text; the fixed correlation with particular command syntax has been
  5414 discontinued;
  5415 
  5416 * Pure: new method 'rules' is particularly well-suited for proof
  5417 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  5418 but often produces more compact proof terms with less detours;
  5419 
  5420 * Pure/Provers/classical: simplified integration with pure rule
  5421 attributes and methods; the classical "intro?/elim?/dest?"
  5422 declarations coincide with the pure ones; the "rule" method no longer
  5423 includes classically swapped intros; "intro" and "elim" methods no
  5424 longer pick rules from the context; also got rid of ML declarations
  5425 AddXIs/AddXEs/AddXDs; all of this has some potential for
  5426 INCOMPATIBILITY;
  5427 
  5428 * Provers/classical: attribute 'swapped' produces classical inversions
  5429 of introduction rules;
  5430 
  5431 * Provers/simplifier: 'simplified' attribute may refer to explicit
  5432 rules instead of full simplifier context; 'iff' attribute handles
  5433 conditional rules;
  5434 
  5435 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  5436 
  5437 * HOL: 'recdef' now fails on unfinished automated proofs, use
  5438 "(permissive)" option to recover old behavior;
  5439 
  5440 * HOL: 'inductive' no longer features separate (collective) attributes
  5441 for 'intros' (was found too confusing);
  5442 
  5443 * HOL: properly declared induction rules less_induct and
  5444 wf_induct_rule;
  5445 
  5446 
  5447 *** HOL ***
  5448 
  5449 * HOL: moved over to sane numeral syntax; the new policy is as
  5450 follows:
  5451 
  5452   - 0 and 1 are polymorphic constants, which are defined on any
  5453   numeric type (nat, int, real etc.);
  5454 
  5455   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  5456   binary representation internally;
  5457 
  5458   - type nat has special constructor Suc, and generally prefers Suc 0
  5459   over 1::nat and Suc (Suc 0) over 2::nat;
  5460 
  5461 This change may cause significant problems of INCOMPATIBILITY; here
  5462 are some hints on converting existing sources:
  5463 
  5464   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  5465   entities, so expressions involving "-" (unary or binary minus) need
  5466   to be spaced properly;
  5467 
  5468   - existing occurrences of "1" may need to be constraint "1::nat" or
  5469   even replaced by Suc 0; similar for old "2";
  5470 
  5471   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  5472 
  5473   - remove all special provisions on numerals in proofs;
  5474 
  5475 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  5476 representation (depends on bin_arith_simps in the default context);
  5477 
  5478 * HOL: symbolic syntax for x^2 (numeral 2);
  5479 
  5480 * HOL: the class of all HOL types is now called "type" rather than
  5481 "term"; INCOMPATIBILITY, need to adapt references to this type class
  5482 in axclass/classes, instance/arities, and (usually rare) occurrences
  5483 in typings (of consts etc.); internally the class is called
  5484 "HOL.type", ML programs should refer to HOLogic.typeS;
  5485 
  5486 * HOL/record package improvements:
  5487   - new derived operations "fields" to build a partial record section,
  5488     "extend" to promote a fixed record to a record scheme, and
  5489     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  5490     declared as simp by default;
  5491   - shared operations ("more", "fields", etc.) now need to be always
  5492     qualified) --- potential INCOMPATIBILITY;
  5493   - removed "make_scheme" operations (use "make" with "extend") --
  5494     INCOMPATIBILITY;
  5495   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  5496   - provides cases/induct rules for use with corresponding Isar
  5497     methods (for concrete records, record schemes, concrete more
  5498     parts, and schematic more parts -- in that order);
  5499   - internal definitions directly based on a light-weight abstract
  5500     theory of product types over typedef rather than datatype;
  5501 
  5502 * HOL: generic code generator for generating executable ML code from
  5503 specifications; specific support for HOL constructs such as inductive
  5504 datatypes and sets, as well as recursive functions; can be invoked
  5505 via 'generate_code' theory section;
  5506 
  5507 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  5508 
  5509 * HOL: consolidated and renamed several theories.  In particular:
  5510         Ord.thy has been absorbed into HOL.thy
  5511         String.thy has been absorbed into List.thy
  5512 
  5513 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  5514 (beware of argument permutation!);
  5515 
  5516 * HOL: linorder_less_split superseded by linorder_cases;
  5517 
  5518 * HOL/List: "nodups" renamed to "distinct";
  5519 
  5520 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  5521 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  5522   - Ex_def has changed, now need to use some_eq_ex
  5523 
  5524 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  5525 in this (rare) case use:
  5526 
  5527   delSWrapper "split_all_tac"
  5528   addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
  5529 
  5530 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
  5531 MAY FAIL;
  5532 
  5533 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
  5534 Isabelle's type classes, ^ on functions and relations has too general
  5535 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be
  5536 necessary to attach explicit type constraints;
  5537 
  5538 * HOL/Relation: the prefix name of the infix "O" has been changed from
  5539 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been
  5540 renamed accordingly (eg "compI" -> "rel_compI").
  5541 
  5542 * HOL: syntax translations now work properly with numerals and records
  5543 expressions;
  5544 
  5545 * HOL: bounded abstraction now uses syntax "%" / "\<lambda>" instead
  5546 of "lam" -- INCOMPATIBILITY;
  5547 
  5548 * HOL: got rid of some global declarations (potential INCOMPATIBILITY
  5549 for ML tools): const "()" renamed "Product_Type.Unity", type "unit"
  5550 renamed "Product_Type.unit";
  5551 
  5552 * HOL: renamed rtrancl_into_rtrancl2 to converse_rtrancl_into_rtrancl
  5553 
  5554 * HOL: removed obsolete theorem "optionE" (use "option.exhaust", or
  5555 the "cases" method);
  5556 
  5557 * HOL/GroupTheory: group theory examples including Sylow's theorem (by
  5558 Florian Kammller);
  5559 
  5560 * HOL/IMP: updated and converted to new-style theory format; several
  5561 parts turned into readable document, with proper Isar proof texts and
  5562 some explanations (by Gerwin Klein);
  5563 
  5564 * HOL-Real: added Complex_Numbers (by Gertrud Bauer);
  5565 
  5566 * HOL-Hyperreal is now a logic image;
  5567 
  5568 
  5569 *** HOLCF ***
  5570 
  5571 * Isar: consts/constdefs supports mixfix syntax for continuous
  5572 operations;
  5573 
  5574 * Isar: domain package adapted to new-style theory format, e.g. see
  5575 HOLCF/ex/Dnat.thy;
  5576 
  5577 * theory Lift: proper use of rep_datatype lift instead of ML hacks --
  5578 potential INCOMPATIBILITY; now use plain induct_tac instead of former
  5579 lift.induct_tac, always use UU instead of Undef;
  5580 
  5581 * HOLCF/IMP: updated and converted to new-style theory;
  5582 
  5583 
  5584 *** ZF ***
  5585 
  5586 * Isar: proper integration of logic-specific tools and packages,
  5587 including theory commands '(co)inductive', '(co)datatype',
  5588 'rep_datatype', 'inductive_cases', as well as methods 'ind_cases',
  5589 'induct_tac', 'case_tac', and 'typecheck' (with attribute 'TC');
  5590 
  5591 * theory Main no longer includes AC; for the Axiom of Choice, base
  5592 your theory on Main_ZFC;
  5593 
  5594 * the integer library now covers quotients and remainders, with many
  5595 laws relating division to addition, multiplication, etc.;
  5596 
  5597 * ZF/UNITY: Chandy and Misra's UNITY is now available in ZF, giving a
  5598 typeless version of the formalism;
  5599 
  5600 * ZF/AC, Coind, IMP, Resid: updated and converted to new-style theory
  5601 format;
  5602 
  5603 * ZF/Induct: new directory for examples of inductive definitions,
  5604 including theory Multiset for multiset orderings; converted to
  5605 new-style theory format;
  5606 
  5607 * ZF: many new theorems about lists, ordinals, etc.;
  5608 
  5609 
  5610 *** General ***
  5611 
  5612 * Pure/kernel: meta-level proof terms (by Stefan Berghofer); reference
  5613 variable proof controls level of detail: 0 = no proofs (only oracle
  5614 dependencies), 1 = lemma dependencies, 2 = compact proof terms; see
  5615 also ref manual for further ML interfaces;
  5616 
  5617 * Pure/axclass: removed obsolete ML interface
  5618 goal_subclass/goal_arity;
  5619 
  5620 * Pure/syntax: new token syntax "num" for plain numerals (without "#"
  5621 of "xnum"); potential INCOMPATIBILITY, since -0, -1 etc. are now
  5622 separate tokens, so expressions involving minus need to be spaced
  5623 properly;
  5624 
  5625 * Pure/syntax: support non-oriented infixes, using keyword "infix"
  5626 rather than "infixl" or "infixr";
  5627 
  5628 * Pure/syntax: concrete syntax for dummy type variables admits genuine
  5629 sort constraint specifications in type inference; e.g. "x::_::foo"
  5630 ensures that the type of "x" is of sort "foo" (but not necessarily a
  5631 type variable);
  5632 
  5633 * Pure/syntax: print modes "type_brackets" and "no_type_brackets"
  5634 control output of nested => (types); the default behavior is
  5635 "type_brackets";
  5636 
  5637 * Pure/syntax: builtin parse translation for "_constify" turns valued
  5638 tokens into AST constants;
  5639 
  5640 * Pure/syntax: prefer later declarations of translations and print
  5641 translation functions; potential INCOMPATIBILITY: need to reverse
  5642 multiple declarations for same syntax element constant;
  5643 
  5644 * Pure/show_hyps reset by default (in accordance to existing Isar
  5645 practice);
  5646 
  5647 * Provers/classical: renamed addaltern to addafter, addSaltern to
  5648 addSafter;
  5649 
  5650 * Provers/clasimp: ``iff'' declarations now handle conditional rules
  5651 as well;
  5652 
  5653 * system: tested support for MacOS X; should be able to get Isabelle +
  5654 Proof General to work in a plain Terminal after installing Poly/ML
  5655 (e.g. from the Isabelle distribution area) and GNU bash alone
  5656 (e.g. from http://www.apple.com); full X11, XEmacs and X-Symbol
  5657 support requires further installations, e.g. from
  5658 http://fink.sourceforge.net/);
  5659 
  5660 * system: support Poly/ML 4.1.1 (able to manage larger heaps);
  5661 
  5662 * system: reduced base memory usage by Poly/ML (approx. 20 MB instead
  5663 of 40 MB), cf. ML_OPTIONS;
  5664 
  5665 * system: Proof General keywords specification is now part of the
  5666 Isabelle distribution (see etc/isar-keywords.el);
  5667 
  5668 * system: support for persistent Proof General sessions (refrain from
  5669 outdating all loaded theories on startup); user may create writable
  5670 logic images like this: ``isabelle -q HOL Test'';
  5671 
  5672 * system: smart selection of Isabelle process versus Isabelle
  5673 interface, accommodates case-insensitive file systems (e.g. HFS+); may
  5674 run both "isabelle" and "Isabelle" even if file names are badly
  5675 damaged (executable inspects the case of the first letter of its own
  5676 name); added separate "isabelle-process" and "isabelle-interface";
  5677 
  5678 * system: refrain from any attempt at filtering input streams; no
  5679 longer support ``8bit'' encoding of old isabelle font, instead proper
  5680 iso-latin characters may now be used; the related isatools
  5681 "symbolinput" and "nonascii" have disappeared as well;
  5682 
  5683 * system: removed old "xterm" interface (the print modes "xterm" and
  5684 "xterm_color" are still available for direct use in a suitable
  5685 terminal);
  5686 
  5687 
  5688 
  5689 New in Isabelle99-2 (February 2001)
  5690 -----------------------------------
  5691 
  5692 *** Overview of INCOMPATIBILITIES ***
  5693 
  5694 * HOL: please note that theories in the Library and elsewhere often use the
  5695 new-style (Isar) format; to refer to their theorems in an ML script you must
  5696 bind them to ML identifers by e.g.      val thm_name = thm "thm_name";
  5697 
  5698 * HOL: inductive package no longer splits induction rule aggressively,
  5699 but only as far as specified by the introductions given; the old
  5700 format may be recovered via ML function complete_split_rule or attribute
  5701 'split_rule (complete)';
  5702 
  5703 * HOL: induct renamed to lfp_induct, lfp_Tarski to lfp_unfold,
  5704 gfp_Tarski to gfp_unfold;
  5705 
  5706 * HOL: contrapos, contrapos2 renamed to contrapos_nn, contrapos_pp;
  5707 
  5708 * HOL: infix "dvd" now has priority 50 rather than 70 (because it is a
  5709 relation); infix "^^" has been renamed "``"; infix "``" has been
  5710 renamed "`"; "univalent" has been renamed "single_valued";
  5711 
  5712 * HOL/Real: "rinv" and "hrinv" replaced by overloaded "inverse"
  5713 operation;
  5714 
  5715 * HOLCF: infix "`" has been renamed "$"; the symbol syntax is \<cdot>;
  5716 
  5717 * Isar: 'obtain' no longer declares "that" fact as simp/intro;
  5718 
  5719 * Isar/HOL: method 'induct' now handles non-atomic goals; as a
  5720 consequence, it is no longer monotonic wrt. the local goal context
  5721 (which is now passed through the inductive cases);
  5722 
  5723 * Document preparation: renamed standard symbols \<ll> to \<lless> and
  5724 \<gg> to \<ggreater>;
  5725 
  5726 
  5727 *** Document preparation ***
  5728 
  5729 * \isabellestyle{NAME} selects version of Isabelle output (currently
  5730 available: are "it" for near math-mode best-style output, "sl" for
  5731 slanted text style, and "tt" for plain type-writer; if no
  5732 \isabellestyle command is given, output is according to slanted
  5733 type-writer);
  5734 
  5735 * support sub/super scripts (for single symbols only), input syntax is
  5736 like this: "A\<^sup>*" or "A\<^sup>\<star>";
  5737 
  5738 * some more standard symbols; see Appendix A of the system manual for
  5739 the complete list of symbols defined in isabellesym.sty;
  5740 
  5741 * improved isabelle style files; more abstract symbol implementation
  5742 (should now use \isamath{...} and \isatext{...} in custom symbol
  5743 definitions);
  5744 
  5745 * antiquotation @{goals} and @{subgoals} for output of *dynamic* goals
  5746 state; Note that presentation of goal states does not conform to
  5747 actual human-readable proof documents.  Please do not include goal
  5748 states into document output unless you really know what you are doing!
  5749 
  5750 * proper indentation of antiquoted output with proportional LaTeX
  5751 fonts;
  5752 
  5753 * no_document ML operator temporarily disables LaTeX document
  5754 generation;
  5755 
  5756 * isatool unsymbolize tunes sources for plain ASCII communication;
  5757 
  5758 
  5759 *** Isar ***
  5760 
  5761 * Pure: Isar now suffers initial goal statements to contain unbound
  5762 schematic variables (this does not conform to actual readable proof
  5763 documents, due to unpredictable outcome and non-compositional proof
  5764 checking); users who know what they are doing may use schematic goals
  5765 for Prolog-style synthesis of proven results;
  5766 
  5767 * Pure: assumption method (an implicit finishing) now handles actual
  5768 rules as well;
  5769 
  5770 * Pure: improved 'obtain' --- moved to Pure, insert "that" into
  5771 initial goal, declare "that" only as Pure intro (only for single
  5772 steps); the "that" rule assumption may now be involved in implicit
  5773 finishing, thus ".." becomes a feasible for trivial obtains;
  5774 
  5775 * Pure: default proof step now includes 'intro_classes'; thus trivial
  5776 instance proofs may be performed by "..";
  5777 
  5778 * Pure: ?thesis / ?this / "..." now work for pure meta-level
  5779 statements as well;
  5780 
  5781 * Pure: more robust selection of calculational rules;
  5782 
  5783 * Pure: the builtin notion of 'finished' goal now includes the ==-refl
  5784 rule (as well as the assumption rule);
  5785 
  5786 * Pure: 'thm_deps' command visualizes dependencies of theorems and
  5787 lemmas, using the graph browser tool;
  5788 
  5789 * Pure: predict failure of "show" in interactive mode;
  5790 
  5791 * Pure: 'thms_containing' now takes actual terms as arguments;
  5792 
  5793 * HOL: improved method 'induct' --- now handles non-atomic goals
  5794 (potential INCOMPATIBILITY); tuned error handling;
  5795 
  5796 * HOL: cases and induct rules now provide explicit hints about the
  5797 number of facts to be consumed (0 for "type" and 1 for "set" rules);
  5798 any remaining facts are inserted into the goal verbatim;
  5799 
  5800 * HOL: local contexts (aka cases) may now contain term bindings as
  5801 well; the 'cases' and 'induct' methods new provide a ?case binding for
  5802 the result to be shown in each case;
  5803 
  5804 * HOL: added 'recdef_tc' command;
  5805 
  5806 * isatool convert assists in eliminating legacy ML scripts;
  5807 
  5808 
  5809 *** HOL ***
  5810 
  5811 * HOL/Library: a collection of generic theories to be used together
  5812 with main HOL; the theory loader path already includes this directory
  5813 by default; the following existing theories have been moved here:
  5814 HOL/Induct/Multiset, HOL/Induct/Acc (as Accessible_Part), HOL/While
  5815 (as While_Combinator), HOL/Lex/Prefix (as List_Prefix);
  5816 
  5817 * HOL/Unix: "Some aspects of Unix file-system security", a typical
  5818 modelling and verification task performed in Isabelle/HOL +
  5819 Isabelle/Isar + Isabelle document preparation (by Markus Wenzel).
  5820 
  5821 * HOL/Algebra: special summation operator SUM no longer exists, it has
  5822 been replaced by setsum; infix 'assoc' now has priority 50 (like
  5823 'dvd'); axiom 'one_not_zero' has been moved from axclass 'ring' to
  5824 'domain', this makes the theory consistent with mathematical
  5825 literature;
  5826 
  5827 * HOL basics: added overloaded operations "inverse" and "divide"
  5828 (infix "/"), syntax for generic "abs" operation, generic summation
  5829 operator \<Sum>;
  5830 
  5831 * HOL/typedef: simplified package, provide more useful rules (see also
  5832 HOL/subset.thy);
  5833 
  5834 * HOL/datatype: induction rule for arbitrarily branching datatypes is
  5835 now expressed as a proper nested rule (old-style tactic scripts may
  5836 require atomize_strip_tac to cope with non-atomic premises);
  5837 
  5838 * HOL: renamed theory "Prod" to "Product_Type", renamed "split" rule
  5839 to "split_conv" (old name still available for compatibility);
  5840 
  5841 * HOL: improved concrete syntax for strings (e.g. allows translation
  5842 rules with string literals);
  5843 
  5844 * HOL-Real-Hyperreal: this extends HOL-Real with the hyperreals
  5845  and Fleuriot's mechanization of analysis, including the transcendental
  5846  functions for the reals;
  5847 
  5848 * HOL/Real, HOL/Hyperreal: improved arithmetic simplification;
  5849 
  5850 
  5851 *** CTT ***
  5852 
  5853 * CTT: x-symbol support for Pi, Sigma, -->, : (membership); note that
  5854 "lam" is displayed as TWO lambda-symbols
  5855 
  5856 * CTT: theory Main now available, containing everything (that is, Bool
  5857 and Arith);
  5858 
  5859 
  5860 *** General ***
  5861 
  5862 * Pure: the Simplifier has been implemented properly as a derived rule
  5863 outside of the actual kernel (at last!); the overall performance
  5864 penalty in practical applications is about 50%, while reliability of
  5865 the Isabelle inference kernel has been greatly improved;
  5866 
  5867 * print modes "brackets" and "no_brackets" control output of nested =>
  5868 (types) and ==> (props); the default behaviour is "brackets";
  5869 
  5870 * Provers: fast_tac (and friends) now handle actual object-logic rules
  5871 as assumptions as well;
  5872 
  5873 * system: support Poly/ML 4.0;
  5874 
  5875 * system: isatool install handles KDE version 1 or 2;
  5876 
  5877 
  5878 
  5879 New in Isabelle99-1 (October 2000)
  5880 ----------------------------------
  5881 
  5882 *** Overview of INCOMPATIBILITIES ***
  5883 
  5884 * HOL: simplification of natural numbers is much changed; to partly
  5885 recover the old behaviour (e.g. to prevent n+n rewriting to #2*n)
  5886 issue the following ML commands:
  5887 
  5888   Delsimprocs Nat_Numeral_Simprocs.cancel_numerals;
  5889   Delsimprocs [Nat_Numeral_Simprocs.combine_numerals];
  5890 
  5891 * HOL: simplification no longer dives into case-expressions; this is
  5892 controlled by "t.weak_case_cong" for each datatype t;
  5893 
  5894 * HOL: nat_less_induct renamed to less_induct;
  5895 
  5896 * HOL: systematic renaming of the SOME (Eps) rules, may use isatool
  5897 fixsome to patch .thy and .ML sources automatically;
  5898 
  5899   select_equality  -> some_equality
  5900   select_eq_Ex     -> some_eq_ex
  5901   selectI2EX       -> someI2_ex
  5902   selectI2         -> someI2
  5903   selectI          -> someI
  5904   select1_equality -> some1_equality
  5905   Eps_sym_eq       -> some_sym_eq_trivial
  5906   Eps_eq           -> some_eq_trivial
  5907 
  5908 * HOL: exhaust_tac on datatypes superceded by new generic case_tac;
  5909 
  5910 * HOL: removed obsolete theorem binding expand_if (refer to split_if
  5911 instead);
  5912 
  5913 * HOL: the recursion equations generated by 'recdef' are now called
  5914 f.simps instead of f.rules;
  5915 
  5916 * HOL: qed_spec_mp now also handles bounded ALL as well;
  5917 
  5918 * HOL: 0 is now overloaded, so the type constraint ":: nat" may
  5919 sometimes be needed;
  5920 
  5921 * HOL: the constant for "f``x" is now "image" rather than "op ``";
  5922 
  5923 * HOL: the constant for "f-``x" is now "vimage" rather than "op -``";
  5924 
  5925 * HOL: the disjoint sum is now "<+>" instead of "Plus"; the cartesian
  5926 product is now "<*>" instead of "Times"; the lexicographic product is
  5927 now "<*lex*>" instead of "**";
  5928 
  5929 * HOL: theory Sexp is now in HOL/Induct examples (it used to be part
  5930 of main HOL, but was unused); better use HOL's datatype package;
  5931 
  5932 * HOL: removed "symbols" syntax for constant "override" of theory Map;
  5933 the old syntax may be recovered as follows:
  5934 
  5935   syntax (symbols)
  5936     override  :: "('a ~=> 'b) => ('a ~=> 'b) => ('a ~=> 'b)"
  5937       (infixl "\\<oplus>" 100)
  5938 
  5939 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  5940 
  5941 * HOL/ML: even fewer consts are declared as global (see theories Ord,
  5942 Lfp, Gfp, WF); this only affects ML packages that refer to const names
  5943 internally;
  5944 
  5945 * HOL and ZF: syntax for quotienting wrt an equivalence relation
  5946 changed from A/r to A//r;
  5947 
  5948 * ZF: new treatment of arithmetic (nat & int) may break some old
  5949 proofs;
  5950 
  5951 * Isar: renamed some attributes (RS -> THEN, simplify -> simplified,
  5952 rulify -> rule_format, elimify -> elim_format, ...);
  5953 
  5954 * Isar/Provers: intro/elim/dest attributes changed; renamed
  5955 intro/intro!/intro!! flags to intro!/intro/intro? (in most cases, one
  5956 should have to change intro!! to intro? only); replaced "delrule" by
  5957 "rule del";
  5958 
  5959 * Isar/HOL: renamed "intrs" to "intros" in inductive definitions;
  5960 
  5961 * Provers: strengthened force_tac by using new first_best_tac;
  5962 
  5963 * LaTeX document preparation: several changes of isabelle.sty (see
  5964 lib/texinputs);
  5965 
  5966 
  5967 *** Document preparation ***
  5968 
  5969 * formal comments (text blocks etc.) in new-style theories may now
  5970 contain antiquotations of thm/prop/term/typ/text to be presented
  5971 according to latex print mode; concrete syntax is like this:
  5972 @{term[show_types] "f(x) = a + x"};
  5973 
  5974 * isatool mkdir provides easy setup of Isabelle session directories,
  5975 including proper document sources;
  5976 
  5977 * generated LaTeX sources are now deleted after successful run
  5978 (isatool document -c); may retain a copy somewhere else via -D option
  5979 of isatool usedir;
  5980 
  5981 * isatool usedir -D now lets isatool latex -o sty update the Isabelle
  5982 style files, achieving self-contained LaTeX sources and simplifying
  5983 LaTeX debugging;
  5984 
  5985 * old-style theories now produce (crude) LaTeX output as well;
  5986 
  5987 * browser info session directories are now self-contained (may be put
  5988 on WWW server seperately); improved graphs of nested sessions; removed
  5989 graph for 'all sessions';
  5990 
  5991 * several improvements in isabelle style files; \isabellestyle{it}
  5992 produces fake math mode output; \isamarkupheader is now \section by
  5993 default; see lib/texinputs/isabelle.sty etc.;
  5994 
  5995 
  5996 *** Isar ***
  5997 
  5998 * Isar/Pure: local results and corresponding term bindings are now
  5999 subject to Hindley-Milner polymorphism (similar to ML); this
  6000 accommodates incremental type-inference very nicely;
  6001 
  6002 * Isar/Pure: new derived language element 'obtain' supports
  6003 generalized existence reasoning;
  6004 
  6005 * Isar/Pure: new calculational elements 'moreover' and 'ultimately'
  6006 support accumulation of results, without applying any rules yet;
  6007 useful to collect intermediate results without explicit name
  6008 references, and for use with transitivity rules with more than 2
  6009 premises;
  6010 
  6011 * Isar/Pure: scalable support for case-analysis type proofs: new
  6012 'case' language element refers to local contexts symbolically, as
  6013 produced by certain proof methods; internally, case names are attached
  6014 to theorems as "tags";
  6015 
  6016 * Isar/Pure: theory command 'hide' removes declarations from
  6017 class/type/const name spaces;
  6018 
  6019 * Isar/Pure: theory command 'defs' supports option "(overloaded)" to
  6020 indicate potential overloading;
  6021 
  6022 * Isar/Pure: changed syntax of local blocks from {{ }} to { };
  6023 
  6024 * Isar/Pure: syntax of sorts made 'inner', i.e. have to write
  6025 "{a,b,c}" instead of {a,b,c};
  6026 
  6027 * Isar/Pure now provides its own version of intro/elim/dest
  6028 attributes; useful for building new logics, but beware of confusion
  6029 with the version in Provers/classical;
  6030 
  6031 * Isar/Pure: the local context of (non-atomic) goals is provided via
  6032 case name 'antecedent';
  6033 
  6034 * Isar/Pure: removed obsolete 'transfer' attribute (transfer of thms
  6035 to the current context is now done automatically);
  6036 
  6037 * Isar/Pure: theory command 'method_setup' provides a simple interface
  6038 for definining proof methods in ML;
  6039 
  6040 * Isar/Provers: intro/elim/dest attributes changed; renamed
  6041 intro/intro!/intro!! flags to intro!/intro/intro? (INCOMPATIBILITY, in
  6042 most cases, one should have to change intro!! to intro? only);
  6043 replaced "delrule" by "rule del";
  6044 
  6045 * Isar/Provers: new 'hypsubst' method, plain 'subst' method and
  6046 'symmetric' attribute (the latter supercedes [RS sym]);
  6047 
  6048 * Isar/Provers: splitter support (via 'split' attribute and 'simp'
  6049 method modifier); 'simp' method: 'only:' modifier removes loopers as
  6050 well (including splits);
  6051 
  6052 * Isar/Provers: Simplifier and Classical methods now support all kind
  6053 of modifiers used in the past, including 'cong', 'iff', etc.
  6054 
  6055 * Isar/Provers: added 'fastsimp' and 'clarsimp' methods (combination
  6056 of Simplifier and Classical reasoner);
  6057 
  6058 * Isar/HOL: new proof method 'cases' and improved version of 'induct'
  6059 now support named cases; major packages (inductive, datatype, primrec,
  6060 recdef) support case names and properly name parameters;
  6061 
  6062 * Isar/HOL: new transitivity rules for substitution in inequalities --
  6063 monotonicity conditions are extracted to be proven at end of
  6064 calculations;
  6065 
  6066 * Isar/HOL: removed 'case_split' thm binding, should use 'cases' proof
  6067 method anyway;
  6068 
  6069 * Isar/HOL: removed old expand_if = split_if; theorems if_splits =
  6070 split_if split_if_asm; datatype package provides theorems foo.splits =
  6071 foo.split foo.split_asm for each datatype;
  6072 
  6073 * Isar/HOL: tuned inductive package, rename "intrs" to "intros"
  6074 (potential INCOMPATIBILITY), emulation of mk_cases feature for proof
  6075 scripts: new 'inductive_cases' command and 'ind_cases' method; (Note:
  6076 use "(cases (simplified))" method in proper proof texts);
  6077 
  6078 * Isar/HOL: added global 'arith_split' attribute for 'arith' method;
  6079 
  6080 * Isar: names of theorems etc. may be natural numbers as well;
  6081 
  6082 * Isar: 'pr' command: optional arguments for goals_limit and
  6083 ProofContext.prems_limit; no longer prints theory contexts, but only
  6084 proof states;
  6085 
  6086 * Isar: diagnostic commands 'pr', 'thm', 'prop', 'term', 'typ' admit
  6087 additional print modes to be specified; e.g. "pr(latex)" will print
  6088 proof state according to the Isabelle LaTeX style;
  6089 
  6090 * Isar: improved support for emulating tactic scripts, including proof
  6091 methods 'rule_tac' etc., 'cut_tac', 'thin_tac', 'subgoal_tac',
  6092 'rename_tac', 'rotate_tac', 'tactic', and 'case_tac' / 'induct_tac'
  6093 (for HOL datatypes);
  6094 
  6095 * Isar: simplified (more robust) goal selection of proof methods: 1st
  6096 goal, all goals, or explicit goal specifier (tactic emulation); thus
  6097 'proof method scripts' have to be in depth-first order;
  6098 
  6099 * Isar: tuned 'let' syntax: replaced 'as' keyword by 'and';
  6100 
  6101 * Isar: removed 'help' command, which hasn't been too helpful anyway;
  6102 should instead use individual commands for printing items
  6103 (print_commands, print_methods etc.);
  6104 
  6105 * Isar: added 'nothing' --- the empty list of theorems;
  6106 
  6107 
  6108 *** HOL ***
  6109 
  6110 * HOL/MicroJava: formalization of a fragment of Java, together with a
  6111 corresponding virtual machine and a specification of its bytecode
  6112 verifier and a lightweight bytecode verifier, including proofs of
  6113 type-safety; by Gerwin Klein, Tobias Nipkow, David von Oheimb, and
  6114 Cornelia Pusch (see also the homepage of project Bali at
  6115 http://isabelle.in.tum.de/Bali/);
  6116 
  6117 * HOL/Algebra: new theory of rings and univariate polynomials, by
  6118 Clemens Ballarin;
  6119 
  6120 * HOL/NumberTheory: fundamental Theorem of Arithmetic, Chinese
  6121 Remainder Theorem, Fermat/Euler Theorem, Wilson's Theorem, by Thomas M
  6122 Rasmussen;
  6123 
  6124 * HOL/Lattice: fundamental concepts of lattice theory and order
  6125 structures, including duals, properties of bounds versus algebraic
  6126 laws, lattice operations versus set-theoretic ones, the Knaster-Tarski
  6127 Theorem for complete lattices etc.; may also serve as a demonstration
  6128 for abstract algebraic reasoning using axiomatic type classes, and
  6129 mathematics-style proof in Isabelle/Isar; by Markus Wenzel;
  6130 
  6131 * HOL/Prolog: a (bare-bones) implementation of Lambda-Prolog, by David
  6132 von Oheimb;
  6133 
  6134 * HOL/IMPP: extension of IMP with local variables and mutually
  6135 recursive procedures, by David von Oheimb;
  6136 
  6137 * HOL/Lambda: converted into new-style theory and document;
  6138 
  6139 * HOL/ex/Multiquote: example of multiple nested quotations and
  6140 anti-quotations -- basically a generalized version of de-Bruijn
  6141 representation; very useful in avoiding lifting of operations;
  6142 
  6143 * HOL/record: added general record equality rule to simpset; fixed
  6144 select-update simplification procedure to handle extended records as
  6145 well; admit "r" as field name;
  6146 
  6147 * HOL: 0 is now overloaded over the new sort "zero", allowing its use with
  6148 other numeric types and also as the identity of groups, rings, etc.;
  6149 
  6150 * HOL: new axclass plus_ac0 for addition with the AC-laws and 0 as identity.
  6151 Types nat and int belong to this axclass;
  6152 
  6153 * HOL: greatly improved simplification involving numerals of type nat, int, real:
  6154    (i + #8 + j) = Suc k simplifies to  #7 + (i + j) = k
  6155    i*j + k + j*#3*i     simplifies to  #4*(i*j) + k
  6156   two terms #m*u and #n*u are replaced by #(m+n)*u
  6157     (where #m, #n and u can implicitly be 1; this is simproc combine_numerals)
  6158   and the term/formula #m*u+x ~~ #n*u+y simplifies simplifies to #(m-n)+x ~~ y
  6159     or x ~~ #(n-m)+y, where ~~ is one of = < <= or - (simproc cancel_numerals);
  6160 
  6161 * HOL: meson_tac is available (previously in ex/meson.ML); it is a
  6162 powerful prover for predicate logic but knows nothing of clasets; see
  6163 ex/mesontest.ML and ex/mesontest2.ML for example applications;
  6164 
  6165 * HOL: new version of "case_tac" subsumes both boolean case split and
  6166 "exhaust_tac" on datatypes; INCOMPATIBILITY: exhaust_tac no longer
  6167 exists, may define val exhaust_tac = case_tac for ad-hoc portability;
  6168 
  6169 * HOL: simplification no longer dives into case-expressions: only the
  6170 selector expression is simplified, but not the remaining arms; to
  6171 enable full simplification of case-expressions for datatype t, you may
  6172 remove t.weak_case_cong from the simpset, either globally (Delcongs
  6173 [thm"t.weak_case_cong"];) or locally (delcongs [...]).
  6174 
  6175 * HOL/recdef: the recursion equations generated by 'recdef' for
  6176 function 'f' are now called f.simps instead of f.rules; if all
  6177 termination conditions are proved automatically, these simplification
  6178 rules are added to the simpset, as in primrec; rules may be named
  6179 individually as well, resulting in a separate list of theorems for
  6180 each equation;
  6181 
  6182 * HOL/While is a new theory that provides a while-combinator. It
  6183 permits the definition of tail-recursive functions without the
  6184 provision of a termination measure. The latter is necessary once the
  6185 invariant proof rule for while is applied.
  6186 
  6187 * HOL: new (overloaded) notation for the set of elements below/above
  6188 some element: {..u}, {..u(}, {l..}, {)l..}. See theory SetInterval.
  6189 
  6190 * HOL: theorems impI, allI, ballI bound as "strip";
  6191 
  6192 * HOL: new tactic induct_thm_tac: thm -> string -> int -> tactic
  6193 induct_tac th "x1 ... xn" expects th to have a conclusion of the form
  6194 P v1 ... vn and abbreviates res_inst_tac [("v1","x1"),...,("vn","xn")] th;
  6195 
  6196 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  6197 
  6198 * HOL: theory Sexp now in HOL/Induct examples (it used to be part of
  6199 main HOL, but was unused);
  6200 
  6201 * HOL: fewer consts declared as global (e.g. have to refer to
  6202 "Lfp.lfp" instead of "lfp" internally; affects ML packages only);
  6203 
  6204 * HOL: tuned AST representation of nested pairs, avoiding bogus output
  6205 in case of overlap with user translations (e.g. judgements over
  6206 tuples); (note that the underlying logical represenation is still
  6207 bogus);
  6208 
  6209 
  6210 *** ZF ***
  6211 
  6212 * ZF: simplification automatically cancels common terms in arithmetic
  6213 expressions over nat and int;
  6214 
  6215 * ZF: new treatment of nat to minimize type-checking: all operators
  6216 coerce their operands to a natural number using the function natify,
  6217 making the algebraic laws unconditional;
  6218 
  6219 * ZF: as above, for int: operators coerce their operands to an integer
  6220 using the function intify;
  6221 
  6222 * ZF: the integer library now contains many of the usual laws for the
  6223 orderings, including $<=, and monotonicity laws for $+ and $*;
  6224 
  6225 * ZF: new example ZF/ex/NatSum to demonstrate integer arithmetic
  6226 simplification;
  6227 
  6228 * FOL and ZF: AddIffs now available, giving theorems of the form P<->Q
  6229 to the simplifier and classical reasoner simultaneously;
  6230 
  6231 
  6232 *** General ***
  6233 
  6234 * Provers: blast_tac now handles actual object-logic rules as