NEWS
author wenzelm
Sun Aug 22 19:33:01 2010 +0200 (2010-08-22)
changeset 38578 1ebc6b76e5ff
parent 38559 befdd6833ec0
child 38622 86fc906dcd86
permissions -rw-r--r--
misc tuning and simplification;
     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 * Records: logical foundation type for records do not carry a '_type' suffix
    39 any longer.  INCOMPATIBILITY.
    40 
    41 * Code generation for records: more idiomatic representation of record types.
    42 Warning: records are not covered by ancient SML code generation any longer.
    43 INCOMPATIBILITY.  In cases of need, a suitable rep_datatype declaration
    44 helps to succeed then:
    45 
    46   record 'a foo = ...
    47   ...
    48   rep_datatype foo_ext ...
    49 
    50 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
    51 INCOMPATIBILITY.
    52 
    53 * Quickcheck in locales considers interpretations of that locale for
    54 counter example search.
    55 
    56 * Theory Library/Monad_Syntax provides do-syntax for monad types.  Syntax
    57 in Library/State_Monad has been changed to avoid ambiguities.
    58 INCOMPATIBILITY.
    59 
    60 * Code generator: export_code without explicit file declaration prints
    61 to standard output.  INCOMPATIBILITY.
    62 
    63 * Abolished symbol type names:  "prod" and "sum" replace "*" and "+"
    64 respectively.  INCOMPATIBILITY.
    65 
    66 * Constant "split" has been merged with constant "prod_case";  names
    67 of ML functions, facts etc. involving split have been retained so far,
    68 though.  INCOMPATIBILITY.
    69 
    70 * Dropped old infix syntax "mem" for List.member;  use "in set"
    71 instead.  INCOMPATIBILITY.
    72 
    73 * Refactoring of code-generation specific operations in List.thy
    74 
    75   constants
    76     null ~> List.null
    77 
    78   facts
    79     mem_iff ~> member_def
    80     null_empty ~> null_def
    81 
    82 INCOMPATIBILITY.  Note that these were not suppossed to be used
    83 regularly unless for striking reasons;  their main purpose was code
    84 generation.
    85 
    86 * Some previously unqualified names have been qualified:
    87 
    88   types
    89     bool ~> HOL.bool
    90     nat ~> Nat.nat
    91 
    92   constants
    93     Trueprop ~> HOL.Trueprop
    94     True ~> HOL.True
    95     False ~> HOL.False
    96     Not ~> HOL.Not
    97     The ~> HOL.The
    98     All ~> HOL.All
    99     Ex ~> HOL.Ex
   100     Ex1 ~> HOL.Ex1
   101     Let ~> HOL.Let
   102     If ~> HOL.If
   103     Ball ~> Set.Ball
   104     Bex ~> Set.Bex
   105     Suc ~> Nat.Suc
   106     Pair ~> Product_Type.Pair
   107     fst ~> Product_Type.fst
   108     snd ~> Product_Type.snd
   109     curry ~> Product_Type.curry
   110     op : ~> Set.member
   111     Collect ~> Set.Collect
   112 
   113 INCOMPATIBILITY.
   114 
   115 * Removed simplifier congruence rule of "prod_case", as has for long
   116 been the case with "split".  INCOMPATIBILITY.
   117 
   118 * Datatype package: theorems generated for executable equality
   119 (class eq) carry proper names and are treated as default code
   120 equations.
   121 
   122 * List.thy: use various operations from the Haskell prelude when
   123 generating Haskell code.
   124 
   125 * code_simp.ML and method code_simp: simplification with rules determined
   126 by code generator.
   127 
   128 * code generator: do not print function definitions for case
   129 combinators any longer.
   130 
   131 * Multivariate Analysis: Introduced a type class for euclidean space. Most
   132 theorems are now stated in terms of euclidean spaces instead of finite
   133 cartesian products.
   134 
   135   types
   136     real ^ 'n ~>  'a::real_vector
   137               ~>  'a::euclidean_space
   138               ~>  'a::ordered_euclidean_space
   139         (depends on your needs)
   140 
   141   constants
   142      _ $ _        ~> _ $$ _
   143      \<chi> x. _  ~> \<chi>\<chi> x. _
   144      CARD('n)     ~> DIM('a)
   145 
   146 Also note that the indices are now natural numbers and not from some finite
   147 type. Finite cartesian products of euclidean spaces, products of euclidean
   148 spaces the real and complex numbers are instantiated to be euclidean_spaces.
   149 
   150 INCOMPATIBILITY.
   151 
   152 * Inductive package: offers new command "inductive_simps" to automatically
   153 derive instantiated and simplified equations for inductive predicates,
   154 similar to inductive_cases.
   155 
   156 
   157 *** FOL ***
   158 
   159 * All constant names are now qualified.  INCOMPATIBILITY.
   160 
   161 
   162 *** ZF ***
   163 
   164 * All constant names are now qualified.  INCOMPATIBILITY.
   165 
   166 
   167 *** ML ***
   168 
   169 * ML antiquotations @{theory} and @{theory_ref} refer to named
   170 theories from the ancestry of the current context, not any accidental
   171 theory loader state as before.  Potential INCOMPATIBILITY, subtle
   172 change in semantics.
   173 
   174 
   175 *** System ***
   176 
   177 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   178 
   179 
   180 
   181 New in Isabelle2009-2 (June 2010)
   182 ---------------------------------
   183 
   184 *** General ***
   185 
   186 * Authentic syntax for *all* logical entities (type classes, type
   187 constructors, term constants): provides simple and robust
   188 correspondence between formal entities and concrete syntax.  Within
   189 the parse tree / AST representations, "constants" are decorated by
   190 their category (class, type, const) and spelled out explicitly with
   191 their full internal name.
   192 
   193 Substantial INCOMPATIBILITY concerning low-level syntax declarations
   194 and translations (translation rules and translation functions in ML).
   195 Some hints on upgrading:
   196 
   197   - Many existing uses of 'syntax' and 'translations' can be replaced
   198     by more modern 'type_notation', 'notation' and 'abbreviation',
   199     which are independent of this issue.
   200 
   201   - 'translations' require markup within the AST; the term syntax
   202     provides the following special forms:
   203 
   204       CONST c   -- produces syntax version of constant c from context
   205       XCONST c  -- literally c, checked as constant from context
   206       c         -- literally c, if declared by 'syntax'
   207 
   208     Plain identifiers are treated as AST variables -- occasionally the
   209     system indicates accidental variables via the error "rhs contains
   210     extra variables".
   211 
   212     Type classes and type constructors are marked according to their
   213     concrete syntax.  Some old translations rules need to be written
   214     for the "type" category, using type constructor application
   215     instead of pseudo-term application of the default category
   216     "logic".
   217 
   218   - 'parse_translation' etc. in ML may use the following
   219     antiquotations:
   220 
   221       @{class_syntax c}   -- type class c within parse tree / AST
   222       @{term_syntax c}    -- type constructor c within parse tree / AST
   223       @{const_syntax c}   -- ML version of "CONST c" above
   224       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
   225 
   226   - Literal types within 'typed_print_translations', i.e. those *not*
   227     represented as pseudo-terms are represented verbatim.  Use @{class
   228     c} or @{type_name c} here instead of the above syntax
   229     antiquotations.
   230 
   231 Note that old non-authentic syntax was based on unqualified base
   232 names, so all of the above "constant" names would coincide.  Recall
   233 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
   234 diagnose syntax problems.
   235 
   236 * Type constructors admit general mixfix syntax, not just infix.
   237 
   238 * Concrete syntax may be attached to local entities without a proof
   239 body, too.  This works via regular mixfix annotations for 'fix',
   240 'def', 'obtain' etc. or via the explicit 'write' command, which is
   241 similar to the 'notation' command in theory specifications.
   242 
   243 * Discontinued unnamed infix syntax (legacy feature for many years) --
   244 need to specify constant name and syntax separately.  Internal ML
   245 datatype constructors have been renamed from InfixName to Infix etc.
   246 Minor INCOMPATIBILITY.
   247 
   248 * Schematic theorem statements need to be explicitly markup as such,
   249 via commands 'schematic_lemma', 'schematic_theorem',
   250 'schematic_corollary'.  Thus the relevance of the proof is made
   251 syntactically clear, which impacts performance in a parallel or
   252 asynchronous interactive environment.  Minor INCOMPATIBILITY.
   253 
   254 * Use of cumulative prems via "!" in some proof methods has been
   255 discontinued (old legacy feature).
   256 
   257 * References 'trace_simp' and 'debug_simp' have been replaced by
   258 configuration options stored in the context. Enabling tracing (the
   259 case of debugging is similar) in proofs works via
   260 
   261   using [[trace_simp = true]]
   262 
   263 Tracing is then active for all invocations of the simplifier in
   264 subsequent goal refinement steps. Tracing may also still be enabled or
   265 disabled via the ProofGeneral settings menu.
   266 
   267 * Separate commands 'hide_class', 'hide_type', 'hide_const',
   268 'hide_fact' replace the former 'hide' KIND command.  Minor
   269 INCOMPATIBILITY.
   270 
   271 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
   272 more efficient than combinations with -q1 or -q2.
   273 
   274 
   275 *** Pure ***
   276 
   277 * Proofterms record type-class reasoning explicitly, using the
   278 "unconstrain" operation internally.  This eliminates all sort
   279 constraints from a theorem and proof, introducing explicit
   280 OFCLASS-premises.  On the proof term level, this operation is
   281 automatically applied at theorem boundaries, such that closed proofs
   282 are always free of sort constraints.  INCOMPATIBILITY for tools that
   283 inspect proof terms.
   284 
   285 * Local theory specifications may depend on extra type variables that
   286 are not present in the result type -- arguments TYPE('a) :: 'a itself
   287 are added internally.  For example:
   288 
   289   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
   290 
   291 * Predicates of locales introduced by classes carry a mandatory
   292 "class" prefix.  INCOMPATIBILITY.
   293 
   294 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
   295 
   296 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
   297 'class' instead.
   298 
   299 * Command 'code_reflect' allows to incorporate generated ML code into
   300 runtime environment; replaces immature code_datatype antiquotation.
   301 INCOMPATIBILITY.
   302 
   303 * Code generator: simple concept for abstract datatypes obeying
   304 invariants.
   305 
   306 * Code generator: details of internal data cache have no impact on the
   307 user space functionality any longer.
   308 
   309 * Methods "unfold_locales" and "intro_locales" ignore non-locale
   310 subgoals.  This is more appropriate for interpretations with 'where'.
   311 INCOMPATIBILITY.
   312 
   313 * Command 'example_proof' opens an empty proof body.  This allows to
   314 experiment with Isar, without producing any persistent result.
   315 
   316 * Commands 'type_notation' and 'no_type_notation' declare type syntax
   317 within a local theory context, with explicit checking of the
   318 constructors involved (in contrast to the raw 'syntax' versions).
   319 
   320 * Commands 'types' and 'typedecl' now work within a local theory
   321 context -- without introducing dependencies on parameters or
   322 assumptions, which is not possible in Isabelle/Pure.
   323 
   324 * Command 'defaultsort' has been renamed to 'default_sort', it works
   325 within a local theory context.  Minor INCOMPATIBILITY.
   326 
   327 
   328 *** HOL ***
   329 
   330 * Command 'typedef' now works within a local theory context -- without
   331 introducing dependencies on parameters or assumptions, which is not
   332 possible in Isabelle/Pure/HOL.  Note that the logical environment may
   333 contain multiple interpretations of local typedefs (with different
   334 non-emptiness proofs), even in a global theory context.
   335 
   336 * New package for quotient types.  Commands 'quotient_type' and
   337 'quotient_definition' may be used for defining types and constants by
   338 quotient constructions.  An example is the type of integers created by
   339 quotienting pairs of natural numbers:
   340 
   341   fun
   342     intrel :: "(nat * nat) => (nat * nat) => bool"
   343   where
   344     "intrel (x, y) (u, v) = (x + v = u + y)"
   345 
   346   quotient_type int = "nat * nat" / intrel
   347     by (auto simp add: equivp_def expand_fun_eq)
   348 
   349   quotient_definition
   350     "0::int" is "(0::nat, 0::nat)"
   351 
   352 The method "lifting" can be used to lift of theorems from the
   353 underlying "raw" type to the quotient type.  The example
   354 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
   355 construction and provides a reasoning infrastructure for finite sets.
   356 
   357 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
   358 clash with new theory Quotient in Main HOL.
   359 
   360 * Moved the SMT binding into the main HOL session, eliminating
   361 separate HOL-SMT session.
   362 
   363 * List membership infix mem operation is only an input abbreviation.
   364 INCOMPATIBILITY.
   365 
   366 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
   367 for future developements; former Library/Word.thy is still present in
   368 the AFP entry RSAPPS.
   369 
   370 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
   371 longer shadowed.  INCOMPATIBILITY.
   372 
   373 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
   374 INCOMPATIBILITY.
   375 
   376 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
   377 INCOMPATIBILITY.
   378 
   379 * Dropped normalizing_semiring etc; use the facts in semiring classes
   380 instead.  INCOMPATIBILITY.
   381 
   382 * Dropped several real-specific versions of lemmas about floor and
   383 ceiling; use the generic lemmas from theory "Archimedean_Field"
   384 instead.  INCOMPATIBILITY.
   385 
   386   floor_number_of_eq         ~> floor_number_of
   387   le_floor_eq_number_of      ~> number_of_le_floor
   388   le_floor_eq_zero           ~> zero_le_floor
   389   le_floor_eq_one            ~> one_le_floor
   390   floor_less_eq_number_of    ~> floor_less_number_of
   391   floor_less_eq_zero         ~> floor_less_zero
   392   floor_less_eq_one          ~> floor_less_one
   393   less_floor_eq_number_of    ~> number_of_less_floor
   394   less_floor_eq_zero         ~> zero_less_floor
   395   less_floor_eq_one          ~> one_less_floor
   396   floor_le_eq_number_of      ~> floor_le_number_of
   397   floor_le_eq_zero           ~> floor_le_zero
   398   floor_le_eq_one            ~> floor_le_one
   399   floor_subtract_number_of   ~> floor_diff_number_of
   400   floor_subtract_one         ~> floor_diff_one
   401   ceiling_number_of_eq       ~> ceiling_number_of
   402   ceiling_le_eq_number_of    ~> ceiling_le_number_of
   403   ceiling_le_zero_eq         ~> ceiling_le_zero
   404   ceiling_le_eq_one          ~> ceiling_le_one
   405   less_ceiling_eq_number_of  ~> number_of_less_ceiling
   406   less_ceiling_eq_zero       ~> zero_less_ceiling
   407   less_ceiling_eq_one        ~> one_less_ceiling
   408   ceiling_less_eq_number_of  ~> ceiling_less_number_of
   409   ceiling_less_eq_zero       ~> ceiling_less_zero
   410   ceiling_less_eq_one        ~> ceiling_less_one
   411   le_ceiling_eq_number_of    ~> number_of_le_ceiling
   412   le_ceiling_eq_zero         ~> zero_le_ceiling
   413   le_ceiling_eq_one          ~> one_le_ceiling
   414   ceiling_subtract_number_of ~> ceiling_diff_number_of
   415   ceiling_subtract_one       ~> ceiling_diff_one
   416 
   417 * Theory "Finite_Set": various folding_XXX locales facilitate the
   418 application of the various fold combinators on finite sets.
   419 
   420 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
   421 provides abstract red-black tree type which is backed by "RBT_Impl" as
   422 implementation.  INCOMPATIBILTY.
   423 
   424 * Theory Library/Coinductive_List has been removed -- superseded by
   425 AFP/thys/Coinductive.
   426 
   427 * Theory PReal, including the type "preal" and related operations, has
   428 been removed.  INCOMPATIBILITY.
   429 
   430 * Real: new development using Cauchy Sequences.
   431 
   432 * Split off theory "Big_Operators" containing setsum, setprod,
   433 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
   434 
   435 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
   436 "Int" etc.  INCOMPATIBILITY.
   437 
   438 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
   439 
   440 * New set of rules "ac_simps" provides combined assoc / commute
   441 rewrites for all interpretations of the appropriate generic locales.
   442 
   443 * Renamed theory "OrderedGroup" to "Groups" and split theory
   444 "Ring_and_Field" into theories "Rings" and "Fields"; for more
   445 appropriate and more consistent names suitable for name prefixes
   446 within the HOL theories.  INCOMPATIBILITY.
   447 
   448 * Some generic constants have been put to appropriate theories:
   449   - less_eq, less: Orderings
   450   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
   451   - inverse, divide: Rings
   452 INCOMPATIBILITY.
   453 
   454 * More consistent naming of type classes involving orderings (and
   455 lattices):
   456 
   457     lower_semilattice                   ~> semilattice_inf
   458     upper_semilattice                   ~> semilattice_sup
   459 
   460     dense_linear_order                  ~> dense_linorder
   461 
   462     pordered_ab_group_add               ~> ordered_ab_group_add
   463     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
   464     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
   465     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
   466     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
   467     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
   468     pordered_cancel_semiring            ~> ordered_cancel_semiring
   469     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
   470     pordered_comm_ring                  ~> ordered_comm_ring
   471     pordered_comm_semiring              ~> ordered_comm_semiring
   472     pordered_ring                       ~> ordered_ring
   473     pordered_ring_abs                   ~> ordered_ring_abs
   474     pordered_semiring                   ~> ordered_semiring
   475 
   476     ordered_ab_group_add                ~> linordered_ab_group_add
   477     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
   478     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
   479     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
   480     ordered_field                       ~> linordered_field
   481     ordered_field_no_lb                 ~> linordered_field_no_lb
   482     ordered_field_no_ub                 ~> linordered_field_no_ub
   483     ordered_field_dense_linear_order    ~> dense_linordered_field
   484     ordered_idom                        ~> linordered_idom
   485     ordered_ring                        ~> linordered_ring
   486     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
   487     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
   488     ordered_ring_strict                 ~> linordered_ring_strict
   489     ordered_semidom                     ~> linordered_semidom
   490     ordered_semiring                    ~> linordered_semiring
   491     ordered_semiring_1                  ~> linordered_semiring_1
   492     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
   493     ordered_semiring_strict             ~> linordered_semiring_strict
   494 
   495   The following slightly odd type classes have been moved to a
   496   separate theory Library/Lattice_Algebras:
   497 
   498     lordered_ab_group_add               ~> lattice_ab_group_add
   499     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
   500     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
   501     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
   502     lordered_ring                       ~> lattice_ring
   503 
   504 INCOMPATIBILITY.
   505 
   506 * Refined field classes:
   507   - classes division_ring_inverse_zero, field_inverse_zero,
   508     linordered_field_inverse_zero include rule inverse 0 = 0 --
   509     subsumes former division_by_zero class;
   510   - numerous lemmas have been ported from field to division_ring.
   511 INCOMPATIBILITY.
   512 
   513 * Refined algebra theorem collections:
   514   - dropped theorem group group_simps, use algebra_simps instead;
   515   - dropped theorem group ring_simps, use field_simps instead;
   516   - proper theorem collection field_simps subsumes former theorem
   517     groups field_eq_simps and field_simps;
   518   - dropped lemma eq_minus_self_iff which is a duplicate for
   519     equal_neg_zero.
   520 INCOMPATIBILITY.
   521 
   522 * Theory Finite_Set and List: some lemmas have been generalized from
   523 sets to lattices:
   524 
   525   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
   526   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
   527   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
   528   union_Union_fold_union        ~> sup_Sup_fold_sup
   529   Inter_fold_inter              ~> Inf_fold_inf
   530   Union_fold_union              ~> Sup_fold_sup
   531   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
   532   union_UNION_fold_union        ~> sup_SUPR_fold_sup
   533   INTER_fold_inter              ~> INFI_fold_inf
   534   UNION_fold_union              ~> SUPR_fold_sup
   535 
   536 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
   537 replaced by the more convenient lemmas Inf_empty and Sup_empty.
   538 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
   539 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
   540 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
   541 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
   542 
   543 * Reorganized theory Multiset: swapped notation of pointwise and
   544 multiset order:
   545 
   546   - pointwise ordering is instance of class order with standard syntax
   547     <= and <;
   548   - multiset ordering has syntax <=# and <#; partial order properties
   549     are provided by means of interpretation with prefix
   550     multiset_order;
   551   - less duplication, less historical organization of sections,
   552     conversion from associations lists to multisets, rudimentary code
   553     generation;
   554   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
   555     if needed.
   556 
   557 Renamed:
   558 
   559   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
   560   multi_count_ext  ~>  multiset_ext
   561   diff_union_inverse2  ~>  diff_union_cancelR
   562 
   563 INCOMPATIBILITY.
   564 
   565 * Theory Permutation: replaced local "remove" by List.remove1.
   566 
   567 * Code generation: ML and OCaml code is decorated with signatures.
   568 
   569 * Theory List: added transpose.
   570 
   571 * Library/Nat_Bijection.thy is a collection of bijective functions
   572 between nat and other types, which supersedes the older libraries
   573 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
   574 
   575   Constants:
   576   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
   577   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
   578   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
   579   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
   580   Countable.pair_encode           ~> prod_encode
   581   NatIso.prod2nat                 ~> prod_encode
   582   NatIso.nat2prod                 ~> prod_decode
   583   NatIso.sum2nat                  ~> sum_encode
   584   NatIso.nat2sum                  ~> sum_decode
   585   NatIso.list2nat                 ~> list_encode
   586   NatIso.nat2list                 ~> list_decode
   587   NatIso.set2nat                  ~> set_encode
   588   NatIso.nat2set                  ~> set_decode
   589 
   590   Lemmas:
   591   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
   592   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
   593   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
   594   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
   595   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
   596   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
   597   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
   598   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
   599   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
   600   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
   601   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
   602   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
   603   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
   604 
   605 * Sledgehammer:
   606   - Renamed ATP commands:
   607     atp_info     ~> sledgehammer running_atps
   608     atp_kill     ~> sledgehammer kill_atps
   609     atp_messages ~> sledgehammer messages
   610     atp_minimize ~> sledgehammer minimize
   611     print_atps   ~> sledgehammer available_atps
   612     INCOMPATIBILITY.
   613   - Added user's manual ("isabelle doc sledgehammer").
   614   - Added option syntax and "sledgehammer_params" to customize
   615     Sledgehammer's behavior.  See the manual for details.
   616   - Modified the Isar proof reconstruction code so that it produces
   617     direct proofs rather than proofs by contradiction.  (This feature
   618     is still experimental.)
   619   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
   620     full-typed mode.
   621   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
   622 
   623 * Nitpick:
   624   - Added and implemented "binary_ints" and "bits" options.
   625   - Added "std" option and implemented support for nonstandard models.
   626   - Added and implemented "finitize" option to improve the precision
   627     of infinite datatypes based on a monotonicity analysis.
   628   - Added support for quotient types.
   629   - Added support for "specification" and "ax_specification"
   630     constructs.
   631   - Added support for local definitions (for "function" and
   632     "termination" proofs).
   633   - Added support for term postprocessors.
   634   - Optimized "Multiset.multiset" and "FinFun.finfun".
   635   - Improved efficiency of "destroy_constrs" optimization.
   636   - Fixed soundness bugs related to "destroy_constrs" optimization and
   637     record getters.
   638   - Fixed soundness bug related to higher-order constructors.
   639   - Fixed soundness bug when "full_descrs" is enabled.
   640   - Improved precision of set constructs.
   641   - Added "atoms" option.
   642   - Added cache to speed up repeated Kodkod invocations on the same
   643     problems.
   644   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
   645     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
   646     "SAT4J_Light".  INCOMPATIBILITY.
   647   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
   648     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
   649   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
   650 
   651 * Method "induct" now takes instantiations of the form t, where t is not
   652   a variable, as a shorthand for "x == t", where x is a fresh variable.
   653   If this is not intended, t has to be enclosed in parentheses.
   654   By default, the equalities generated by definitional instantiations
   655   are pre-simplified, which may cause parameters of inductive cases
   656   to disappear, or may even delete some of the inductive cases.
   657   Use "induct (no_simp)" instead of "induct" to restore the old
   658   behaviour. The (no_simp) option is also understood by the "cases"
   659   and "nominal_induct" methods, which now perform pre-simplification, too.
   660   INCOMPATIBILITY.
   661 
   662 
   663 *** HOLCF ***
   664 
   665 * Variable names in lemmas generated by the domain package have
   666 changed; the naming scheme is now consistent with the HOL datatype
   667 package.  Some proof scripts may be affected, INCOMPATIBILITY.
   668 
   669 * The domain package no longer defines the function "foo_copy" for
   670 recursive domain "foo".  The reach lemma is now stated directly in
   671 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
   672 be reformulated in terms of "foo_take", INCOMPATIBILITY.
   673 
   674 * Most definedness lemmas generated by the domain package (previously
   675 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
   676 like "foo$x = UU <-> x = UU", which works better as a simp rule.
   677 Proofs that used definedness lemmas as intro rules may break,
   678 potential INCOMPATIBILITY.
   679 
   680 * Induction and casedist rules generated by the domain package now
   681 declare proper case_names (one called "bottom", and one named for each
   682 constructor).  INCOMPATIBILITY.
   683 
   684 * For mutually-recursive domains, separate "reach" and "take_lemma"
   685 rules are generated for each domain, INCOMPATIBILITY.
   686 
   687   foo_bar.reach       ~> foo.reach  bar.reach
   688   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
   689 
   690 * Some lemmas generated by the domain package have been renamed for
   691 consistency with the datatype package, INCOMPATIBILITY.
   692 
   693   foo.ind        ~> foo.induct
   694   foo.finite_ind ~> foo.finite_induct
   695   foo.coind      ~> foo.coinduct
   696   foo.casedist   ~> foo.exhaust
   697   foo.exhaust    ~> foo.nchotomy
   698 
   699 * For consistency with other definition packages, the fixrec package
   700 now generates qualified theorem names, INCOMPATIBILITY.
   701 
   702   foo_simps  ~> foo.simps
   703   foo_unfold ~> foo.unfold
   704   foo_induct ~> foo.induct
   705 
   706 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
   707 method and internal fixrec proofs now use the default simpset instead.
   708 INCOMPATIBILITY.
   709 
   710 * The "contlub" predicate has been removed.  Proof scripts should use
   711 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
   712 
   713 * The "admw" predicate has been removed, INCOMPATIBILITY.
   714 
   715 * The constants cpair, cfst, and csnd have been removed in favor of
   716 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
   717 
   718 
   719 *** ML ***
   720 
   721 * Antiquotations for basic formal entities:
   722 
   723     @{class NAME}         -- type class
   724     @{class_syntax NAME}  -- syntax representation of the above
   725 
   726     @{type_name NAME}     -- logical type
   727     @{type_abbrev NAME}   -- type abbreviation
   728     @{nonterminal NAME}   -- type of concrete syntactic category
   729     @{type_syntax NAME}   -- syntax representation of any of the above
   730 
   731     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
   732     @{const_abbrev NAME}  -- abbreviated constant
   733     @{const_syntax NAME}  -- syntax representation of any of the above
   734 
   735 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
   736 syntax constant (cf. 'syntax' command).
   737 
   738 * Antiquotation @{make_string} inlines a function to print arbitrary
   739 values similar to the ML toplevel.  The result is compiler dependent
   740 and may fall back on "?" in certain situations.
   741 
   742 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
   743 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
   744 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
   745 not work with the asynchronous Isar document model.
   746 
   747 * Configuration options now admit dynamic default values, depending on
   748 the context or even global references.
   749 
   750 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
   751 uses an efficient external library if available (for Poly/ML).
   752 
   753 * Renamed some important ML structures, while keeping the old names
   754 for some time as aliases within the structure Legacy:
   755 
   756   OuterKeyword  ~>  Keyword
   757   OuterLex      ~>  Token
   758   OuterParse    ~>  Parse
   759   OuterSyntax   ~>  Outer_Syntax
   760   PrintMode     ~>  Print_Mode
   761   SpecParse     ~>  Parse_Spec
   762   ThyInfo       ~>  Thy_Info
   763   ThyLoad       ~>  Thy_Load
   764   ThyOutput     ~>  Thy_Output
   765   TypeInfer     ~>  Type_Infer
   766 
   767 Note that "open Legacy" simplifies porting of sources, but forgetting
   768 to remove it again will complicate porting again in the future.
   769 
   770 * Most operations that refer to a global context are named
   771 accordingly, e.g. Simplifier.global_context or
   772 ProofContext.init_global.  There are some situations where a global
   773 context actually works, but under normal circumstances one needs to
   774 pass the proper local context through the code!
   775 
   776 * Discontinued old TheoryDataFun with its copy/init operation -- data
   777 needs to be pure.  Functor Theory_Data_PP retains the traditional
   778 Pretty.pp argument to merge, which is absent in the standard
   779 Theory_Data version.
   780 
   781 * Sorts.certify_sort and derived "cert" operations for types and terms
   782 no longer minimize sorts.  Thus certification at the boundary of the
   783 inference kernel becomes invariant under addition of class relations,
   784 which is an important monotonicity principle.  Sorts are now minimized
   785 in the syntax layer only, at the boundary between the end-user and the
   786 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
   787 explicitly in rare situations.
   788 
   789 * Renamed old-style Drule.standard to Drule.export_without_context, to
   790 emphasize that this is in no way a standard operation.
   791 INCOMPATIBILITY.
   792 
   793 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
   794 usual for resolution.  Rare INCOMPATIBILITY.
   795 
   796 * Renamed varify/unvarify operations to varify_global/unvarify_global
   797 to emphasize that these only work in a global situation (which is
   798 quite rare).
   799 
   800 * Curried take and drop in library.ML; negative length is interpreted
   801 as infinity (as in chop).  Subtle INCOMPATIBILITY.
   802 
   803 * Proof terms: type substitutions on proof constants now use canonical
   804 order of type variables.  INCOMPATIBILITY for tools working with proof
   805 terms.
   806 
   807 * Raw axioms/defs may no longer carry sort constraints, and raw defs
   808 may no longer carry premises.  User-level specifications are
   809 transformed accordingly by Thm.add_axiom/add_def.
   810 
   811 
   812 *** System ***
   813 
   814 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
   815 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
   816 proof terms are enabled unconditionally in the new HOL-Proofs image.
   817 
   818 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
   819 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
   820 respectively.
   821 
   822 * Old lib/scripts/polyml-platform is superseded by the
   823 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
   824 variant, even on a 64 bit machine.  The following example setting
   825 prefers 64 bit if available:
   826 
   827   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
   828 
   829 * The preliminary Isabelle/jEdit application demonstrates the emerging
   830 Isabelle/Scala layer for advanced prover interaction and integration.
   831 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
   832 component.
   833 
   834 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
   835 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
   836 similar to the default assignment of the document preparation system
   837 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
   838 provides some operations for direct access to the font without asking
   839 the user for manual installation.
   840 
   841 
   842 
   843 New in Isabelle2009-1 (December 2009)
   844 -------------------------------------
   845 
   846 *** General ***
   847 
   848 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
   849 one backslash should be used, even in ML sources.
   850 
   851 
   852 *** Pure ***
   853 
   854 * Locale interpretation propagates mixins along the locale hierarchy.
   855 The currently only available mixins are the equations used to map
   856 local definitions to terms of the target domain of an interpretation.
   857 
   858 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
   859 loc" to print all interpretations of locale "loc" in the theory.
   860 Interpretations in proofs are not shown.
   861 
   862 * Thoroughly revised locales tutorial.  New section on conditional
   863 interpretation.
   864 
   865 * On instantiation of classes, remaining undefined class parameters
   866 are formally declared.  INCOMPATIBILITY.
   867 
   868 
   869 *** Document preparation ***
   870 
   871 * New generalized style concept for printing terms: @{foo (style) ...}
   872 instead of @{foo_style style ...}  (old form is still retained for
   873 backward compatibility).  Styles can be also applied for
   874 antiquotations prop, term_type and typeof.
   875 
   876 
   877 *** HOL ***
   878 
   879 * New proof method "smt" for a combination of first-order logic with
   880 equality, linear and nonlinear (natural/integer/real) arithmetic, and
   881 fixed-size bitvectors; there is also basic support for higher-order
   882 features (esp. lambda abstractions).  It is an incomplete decision
   883 procedure based on external SMT solvers using the oracle mechanism;
   884 for the SMT solver Z3, this method is proof-producing.  Certificates
   885 are provided to avoid calling the external solvers solely for
   886 re-checking proofs.  Due to a remote SMT service there is no need for
   887 installing SMT solvers locally.  See src/HOL/SMT.
   888 
   889 * New commands to load and prove verification conditions generated by
   890 the Boogie program verifier or derived systems (e.g. the Verifying C
   891 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
   892 
   893 * New counterexample generator tool 'nitpick' based on the Kodkod
   894 relational model finder.  See src/HOL/Tools/Nitpick and
   895 src/HOL/Nitpick_Examples.
   896 
   897 * New commands 'code_pred' and 'values' to invoke the predicate
   898 compiler and to enumerate values of inductive predicates.
   899 
   900 * A tabled implementation of the reflexive transitive closure.
   901 
   902 * New implementation of quickcheck uses generic code generator;
   903 default generators are provided for all suitable HOL types, records
   904 and datatypes.  Old quickcheck can be re-activated importing theory
   905 Library/SML_Quickcheck.
   906 
   907 * New testing tool Mirabelle for automated proof tools.  Applies
   908 several tools and tactics like sledgehammer, metis, or quickcheck, to
   909 every proof step in a theory.  To be used in batch mode via the
   910 "mirabelle" utility.
   911 
   912 * New proof method "sos" (sum of squares) for nonlinear real
   913 arithmetic (originally due to John Harison). It requires theory
   914 Library/Sum_Of_Squares.  It is not a complete decision procedure but
   915 works well in practice on quantifier-free real arithmetic with +, -,
   916 *, ^, =, <= and <, i.e. boolean combinations of equalities and
   917 inequalities between polynomials.  It makes use of external
   918 semidefinite programming solvers.  Method "sos" generates a
   919 certificate that can be pasted into the proof thus avoiding the need
   920 to call an external tool every time the proof is checked.  See
   921 src/HOL/Library/Sum_Of_Squares.
   922 
   923 * New method "linarith" invokes existing linear arithmetic decision
   924 procedure only.
   925 
   926 * New command 'atp_minimal' reduces result produced by Sledgehammer.
   927 
   928 * New Sledgehammer option "Full Types" in Proof General settings menu.
   929 Causes full type information to be output to the ATPs.  This slows
   930 ATPs down considerably but eliminates a source of unsound "proofs"
   931 that fail later.
   932 
   933 * New method "metisFT": A version of metis that uses full type
   934 information in order to avoid failures of proof reconstruction.
   935 
   936 * New evaluator "approximate" approximates an real valued term using
   937 the same method as the approximation method.
   938 
   939 * Method "approximate" now supports arithmetic expressions as
   940 boundaries of intervals and implements interval splitting and Taylor
   941 series expansion.
   942 
   943 * ML antiquotation @{code_datatype} inserts definition of a datatype
   944 generated by the code generator; e.g. see src/HOL/Predicate.thy.
   945 
   946 * New theory SupInf of the supremum and infimum operators for sets of
   947 reals.
   948 
   949 * New theory Probability, which contains a development of measure
   950 theory, eventually leading to Lebesgue integration and probability.
   951 
   952 * Extended Multivariate Analysis to include derivation and Brouwer's
   953 fixpoint theorem.
   954 
   955 * Reorganization of number theory, INCOMPATIBILITY:
   956   - new number theory development for nat and int, in theories Divides
   957     and GCD as well as in new session Number_Theory
   958   - some constants and facts now suffixed with _nat and _int
   959     accordingly
   960   - former session NumberTheory now named Old_Number_Theory, including
   961     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
   962   - moved theory Pocklington from src/HOL/Library to
   963     src/HOL/Old_Number_Theory
   964 
   965 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
   966 lcm of finite and infinite sets. It is shown that they form a complete
   967 lattice.
   968 
   969 * Class semiring_div requires superclass no_zero_divisors and proof of
   970 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
   971 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
   972 generalized to class semiring_div, subsuming former theorems
   973 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
   974 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
   975 INCOMPATIBILITY.
   976 
   977 * Refinements to lattice classes and sets:
   978   - less default intro/elim rules in locale variant, more default
   979     intro/elim rules in class variant: more uniformity
   980   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
   981     le_inf_iff
   982   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
   983     sup_aci)
   984   - renamed ACI to inf_sup_aci
   985   - new class "boolean_algebra"
   986   - class "complete_lattice" moved to separate theory
   987     "Complete_Lattice"; corresponding constants (and abbreviations)
   988     renamed and with authentic syntax:
   989     Set.Inf ~>    Complete_Lattice.Inf
   990     Set.Sup ~>    Complete_Lattice.Sup
   991     Set.INFI ~>   Complete_Lattice.INFI
   992     Set.SUPR ~>   Complete_Lattice.SUPR
   993     Set.Inter ~>  Complete_Lattice.Inter
   994     Set.Union ~>  Complete_Lattice.Union
   995     Set.INTER ~>  Complete_Lattice.INTER
   996     Set.UNION ~>  Complete_Lattice.UNION
   997   - authentic syntax for
   998     Set.Pow
   999     Set.image
  1000   - mere abbreviations:
  1001     Set.empty               (for bot)
  1002     Set.UNIV                (for top)
  1003     Set.inter               (for inf, formerly Set.Int)
  1004     Set.union               (for sup, formerly Set.Un)
  1005     Complete_Lattice.Inter  (for Inf)
  1006     Complete_Lattice.Union  (for Sup)
  1007     Complete_Lattice.INTER  (for INFI)
  1008     Complete_Lattice.UNION  (for SUPR)
  1009   - object-logic definitions as far as appropriate
  1010 
  1011 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1012 Un_subset_iff are explicitly deleted as default simp rules; then also
  1013 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1014 deleted to achieve the desired effect.
  1015 
  1016 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1017 rules by default any longer; the same applies to min_max.inf_absorb1
  1018 etc.  INCOMPATIBILITY.
  1019 
  1020 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1021 pred_set_conv by default.  INCOMPATIBILITY.
  1022 
  1023 * Power operations on relations and functions are now one dedicated
  1024 constant "compow" with infix syntax "^^".  Power operation on
  1025 multiplicative monoids retains syntax "^" and is now defined generic
  1026 in class power.  INCOMPATIBILITY.
  1027 
  1028 * Relation composition "R O S" now has a more standard argument order:
  1029 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1030 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1031 break, since the O_assoc rule was not rewritten like this.  Fix using
  1032 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1033 
  1034 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1035 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1036 INCOMPATIBILITY.
  1037 
  1038 * Most rules produced by inductive and datatype package have mandatory
  1039 prefixes.  INCOMPATIBILITY.
  1040 
  1041 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1042 the attribute of the same name.  Each of the theorems in the list
  1043 DERIV_intros assumes composition with an additional function and
  1044 matches a variable to the derivative, which has to be solved by the
  1045 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1046 of most elementary terms.  Former Maclauren.DERIV_tac and
  1047 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1048 INCOMPATIBILITY.
  1049 
  1050 * Code generator attributes follow the usual underscore convention:
  1051     code_unfold     replaces    code unfold
  1052     code_post       replaces    code post
  1053     etc.
  1054   INCOMPATIBILITY.
  1055 
  1056 * Renamed methods:
  1057     sizechange -> size_change
  1058     induct_scheme -> induction_schema
  1059   INCOMPATIBILITY.
  1060 
  1061 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1062 INCOMPATIBILITY, use "undefined" directly.
  1063 
  1064 * Renamed theorems:
  1065     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1066     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1067     Suc_plus1 -> Suc_eq_plus1
  1068     *anti_sym -> *antisym*
  1069     vector_less_eq_def -> vector_le_def
  1070   INCOMPATIBILITY.
  1071 
  1072 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1073 INCOMPATIBILITY.
  1074 
  1075 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1076 INCOMPATIBILITY.
  1077 
  1078 
  1079 *** HOLCF ***
  1080 
  1081 * Theory Representable defines a class "rep" of domains that are
  1082 representable (via an ep-pair) in the universal domain type "udom".
  1083 Instances are provided for all type constructors defined in HOLCF.
  1084 
  1085 * The 'new_domain' command is a purely definitional version of the
  1086 domain package, for representable domains.  Syntax is identical to the
  1087 old domain package.  The 'new_domain' package also supports indirect
  1088 recursion using previously-defined type constructors.  See
  1089 src/HOLCF/ex/New_Domain.thy for examples.
  1090 
  1091 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1092 on the left-hand side of an equation, and then performs
  1093 simplification.  Rewriting is done using rules declared with the
  1094 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1095 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1096 
  1097 * The pattern-match compiler in 'fixrec' can now handle constructors
  1098 with HOL function types.  Pattern-match combinators for the Pair
  1099 constructor are pre-configured.
  1100 
  1101 * The 'fixrec' package now produces better fixed-point induction rules
  1102 for mutually-recursive definitions:  Induction rules have conclusions
  1103 of the form "P foo bar" instead of "P <foo, bar>".
  1104 
  1105 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1106 been renamed to "below".  The name "below" now replaces "less" in many
  1107 theorem names.  (Legacy theorem names using "less" are still supported
  1108 as well.)
  1109 
  1110 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1111 patterns can be used to generate strictness rules, or to make
  1112 functions more strict (much like the bang-patterns supported by the
  1113 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1114 examples.
  1115 
  1116 
  1117 *** ML ***
  1118 
  1119 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1120 errors and run-time exceptions, including detailed source positions.
  1121 
  1122 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1123 identified entries, with some additional information such as source
  1124 position, logical grouping etc.
  1125 
  1126 * Theory and context data is now introduced by the simplified and
  1127 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1128 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1129 copy operation) is still available for some time.
  1130 
  1131 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1132 provides a high-level programming interface to synchronized state
  1133 variables with atomic update.  This works via pure function
  1134 application within a critical section -- its runtime should be as
  1135 short as possible; beware of deadlocks if critical code is nested,
  1136 either directly or indirectly via other synchronized variables!
  1137 
  1138 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1139 wraps raw ML references, explicitly indicating their non-thread-safe
  1140 behaviour.  The Isar toplevel keeps this structure open, to
  1141 accommodate Proof General as well as quick and dirty interactive
  1142 experiments with references.
  1143 
  1144 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1145 parallel tactical reasoning.
  1146 
  1147 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1148 are similar to SUBPROOF, but are slightly more flexible: only the
  1149 specified parts of the subgoal are imported into the context, and the
  1150 body tactic may introduce new subgoals and schematic variables.
  1151 
  1152 * Old tactical METAHYPS, which does not observe the proof context, has
  1153 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1154 or Subgoal.FOCUS etc.
  1155 
  1156 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1157 functors have their own ML name space there is no point to mark them
  1158 separately.)  Minor INCOMPATIBILITY.
  1159 
  1160 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1161 
  1162 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1163 INCOMPATIBILITY.
  1164 
  1165 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1166 mode, which avoids critical setmp.
  1167 
  1168 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1169 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1170 Attrib/Method.setup introduced in Isabelle2009.
  1171 
  1172 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1173 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1174 last resort.  INCOMPATIBILITY.
  1175 
  1176 * Display.pretty_thm now requires a proper context (cf. former
  1177 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1178 or even Display.pretty_thm_without_context as last resort.
  1179 INCOMPATIBILITY.
  1180 
  1181 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1182 Syntax.pretty_typ/term directly, preferably with proper context
  1183 instead of global theory.
  1184 
  1185 
  1186 *** System ***
  1187 
  1188 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1189 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1190 usedir option -q.
  1191 
  1192 * Support for additional "Isabelle components" via etc/components, see
  1193 also the system manual.
  1194 
  1195 * The isabelle makeall tool now operates on all components with
  1196 IsaMakefile, not just hardwired "logics".
  1197 
  1198 * Removed "compress" option from isabelle-process and isabelle usedir;
  1199 this is always enabled.
  1200 
  1201 * Discontinued support for Poly/ML 4.x versions.
  1202 
  1203 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  1204 on a given logic image.  This requires the lighttpd webserver and is
  1205 currently supported on Linux only.
  1206 
  1207 
  1208 
  1209 New in Isabelle2009 (April 2009)
  1210 --------------------------------
  1211 
  1212 *** General ***
  1213 
  1214 * Simplified main Isabelle executables, with less surprises on
  1215 case-insensitive file-systems (such as Mac OS).
  1216 
  1217   - The main Isabelle tool wrapper is now called "isabelle" instead of
  1218     "isatool."
  1219 
  1220   - The former "isabelle" alias for "isabelle-process" has been
  1221     removed (should rarely occur to regular users).
  1222 
  1223   - The former "isabelle-interface" and its alias "Isabelle" have been
  1224     removed (interfaces are now regular Isabelle tools).
  1225 
  1226 Within scripts and make files, the Isabelle environment variables
  1227 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  1228 respectively.  (The latter are still available as legacy feature.)
  1229 
  1230 The old isabelle-interface wrapper could react in confusing ways if
  1231 the interface was uninstalled or changed otherwise.  Individual
  1232 interface tool configuration is now more explicit, see also the
  1233 Isabelle system manual.  In particular, Proof General is now available
  1234 via "isabelle emacs".
  1235 
  1236 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  1237 purge installed copies of Isabelle executables and re-run "isabelle
  1238 install -p ...", or use symlinks.
  1239 
  1240 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  1241 old ~/isabelle, which was slightly non-standard and apt to cause
  1242 surprises on case-insensitive file-systems (such as Mac OS).
  1243 
  1244 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  1245 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  1246 care is required when using older releases of Isabelle.  Note that
  1247 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  1248 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  1249 
  1250 * Proofs of fully specified statements are run in parallel on
  1251 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  1252 a regular 4-core machine, if the initial heap space is made reasonably
  1253 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  1254 
  1255 * The main reference manuals ("isar-ref", "implementation", and
  1256 "system") have been updated and extended.  Formally checked references
  1257 as hyperlinks are now available uniformly.
  1258 
  1259 
  1260 *** Pure ***
  1261 
  1262 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  1263 respects.  The most important changes are listed below.  See the
  1264 Tutorial on Locales ("locales" manual) for details.
  1265 
  1266 - In locale expressions, instantiation replaces renaming.  Parameters
  1267 must be declared in a for clause.  To aid compatibility with previous
  1268 parameter inheritance, in locale declarations, parameters that are not
  1269 'touched' (instantiation position "_" or omitted) are implicitly added
  1270 with their syntax at the beginning of the for clause.
  1271 
  1272 - Syntax from abbreviations and definitions in locales is available in
  1273 locale expressions and context elements.  The latter is particularly
  1274 useful in locale declarations.
  1275 
  1276 - More flexible mechanisms to qualify names generated by locale
  1277 expressions.  Qualifiers (prefixes) may be specified in locale
  1278 expressions, and can be marked as mandatory (syntax: "name!:") or
  1279 optional (syntax "name?:").  The default depends for plain "name:"
  1280 depends on the situation where a locale expression is used: in
  1281 commands 'locale' and 'sublocale' prefixes are optional, in
  1282 'interpretation' and 'interpret' prefixes are mandatory.  The old
  1283 implicit qualifiers derived from the parameter names of a locale are
  1284 no longer generated.
  1285 
  1286 - Command "sublocale l < e" replaces "interpretation l < e".  The
  1287 instantiation clause in "interpretation" and "interpret" (square
  1288 brackets) is no longer available.  Use locale expressions.
  1289 
  1290 - When converting proof scripts, mandatory qualifiers in
  1291 'interpretation' and 'interpret' should be retained by default, even
  1292 if this is an INCOMPATIBILITY compared to former behavior.  In the
  1293 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  1294 in locale expressions range over a single locale instance only.
  1295 
  1296 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  1297 In existing theorem specifications replace the includes element by the
  1298 respective context elements of the included locale, omitting those
  1299 that are already present in the theorem specification.  Multiple
  1300 assume elements of a locale should be replaced by a single one
  1301 involving the locale predicate.  In the proof body, declarations (most
  1302 notably theorems) may be regained by interpreting the respective
  1303 locales in the proof context as required (command "interpret").
  1304 
  1305 If using "includes" in replacement of a target solely because the
  1306 parameter types in the theorem are not as general as in the target,
  1307 consider declaring a new locale with additional type constraints on
  1308 the parameters (context element "constrains").
  1309 
  1310 - Discontinued "locale (open)".  INCOMPATIBILITY.
  1311 
  1312 - Locale interpretation commands no longer attempt to simplify goal.
  1313 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  1314 methods intro_locales and unfold_locales to clarify.
  1315 
  1316 - Locale interpretation commands no longer accept interpretation
  1317 attributes.  INCOMPATIBILITY.
  1318 
  1319 * Class declaration: so-called "base sort" must not be given in import
  1320 list any longer, but is inferred from the specification.  Particularly
  1321 in HOL, write
  1322 
  1323     class foo = ...
  1324 
  1325 instead of
  1326 
  1327     class foo = type + ...
  1328 
  1329 * Class target: global versions of theorems stemming do not carry a
  1330 parameter prefix any longer.  INCOMPATIBILITY.
  1331 
  1332 * Class 'instance' command no longer accepts attached definitions.
  1333 INCOMPATIBILITY, use proper 'instantiation' target instead.
  1334 
  1335 * Recovered hiding of consts, which was accidentally broken in
  1336 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  1337 makes c inaccessible; consider using ``hide (open) const c'' instead.
  1338 
  1339 * Slightly more coherent Pure syntax, with updated documentation in
  1340 isar-ref manual.  Removed locales meta_term_syntax and
  1341 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  1342 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  1343 directly in regular applications.
  1344 
  1345 * There is a new syntactic category "float_const" for signed decimal
  1346 fractions (e.g. 123.45 or -123.45).
  1347 
  1348 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  1349 interface with 'setup' command instead.
  1350 
  1351 * Command 'local_setup' is similar to 'setup', but operates on a local
  1352 theory context.
  1353 
  1354 * The 'axiomatization' command now only works within a global theory
  1355 context.  INCOMPATIBILITY.
  1356 
  1357 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  1358 hypotheses.  Sorts required in the course of reasoning need to be
  1359 covered by the constraints in the initial statement, completed by the
  1360 type instance information of the background theory.  Non-trivial sort
  1361 hypotheses, which rarely occur in practice, may be specified via
  1362 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  1363 
  1364   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  1365 
  1366 The result contains an implicit sort hypotheses as before --
  1367 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  1368 normalization.
  1369 
  1370 * Generalized Isar history, with support for linear undo, direct state
  1371 addressing etc.
  1372 
  1373 * Changed defaults for unify configuration options:
  1374 
  1375   unify_trace_bound = 50 (formerly 25)
  1376   unify_search_bound = 60 (formerly 30)
  1377 
  1378 * Different bookkeeping for code equations (INCOMPATIBILITY):
  1379 
  1380   a) On theory merge, the last set of code equations for a particular
  1381      constant is taken (in accordance with the policy applied by other
  1382      parts of the code generator framework).
  1383 
  1384   b) Code equations stemming from explicit declarations (e.g. code
  1385      attribute) gain priority over default code equations stemming
  1386      from definition, primrec, fun etc.
  1387 
  1388 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  1389 
  1390 * Unified theorem tables for both code generators.  Thus [code
  1391 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  1392 
  1393 * Command 'find_consts' searches for constants based on type and name
  1394 patterns, e.g.
  1395 
  1396     find_consts "_ => bool"
  1397 
  1398 By default, matching is against subtypes, but it may be restricted to
  1399 the whole type.  Searching by name is possible.  Multiple queries are
  1400 conjunctive and queries may be negated by prefixing them with a
  1401 hyphen:
  1402 
  1403     find_consts strict: "_ => bool" name: "Int" -"int => int"
  1404 
  1405 * New 'find_theorems' criterion "solves" matches theorems that
  1406 directly solve the current goal (modulo higher-order unification).
  1407 
  1408 * Auto solve feature for main theorem statements: whenever a new goal
  1409 is stated, "find_theorems solves" is called; any theorems that could
  1410 solve the lemma directly are listed as part of the goal state.
  1411 Cf. associated options in Proof General Isabelle settings menu,
  1412 enabled by default, with reasonable timeout for pathological cases of
  1413 higher-order unification.
  1414 
  1415 
  1416 *** Document preparation ***
  1417 
  1418 * Antiquotation @{lemma} now imitates a regular terminal proof,
  1419 demanding keyword 'by' and supporting the full method expression
  1420 syntax just like the Isar command 'by'.
  1421 
  1422 
  1423 *** HOL ***
  1424 
  1425 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  1426 points Main and Complex_Main remain as before.
  1427 
  1428 * Logic image HOL-Plain provides a minimal HOL with the most important
  1429 tools available (inductive, datatype, primrec, ...).  This facilitates
  1430 experimentation and tool development.  Note that user applications
  1431 (and library theories) should never refer to anything below theory
  1432 Main, as before.
  1433 
  1434 * Logic image HOL-Main stops at theory Main, and thus facilitates
  1435 experimentation due to shorter build times.
  1436 
  1437 * Logic image HOL-NSA contains theories of nonstandard analysis which
  1438 were previously part of former HOL-Complex.  Entry point Hyperreal
  1439 remains valid, but theories formerly using Complex_Main should now use
  1440 new entry point Hypercomplex.
  1441 
  1442 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  1443 Posix processes.  Avoids potentially expensive forking of the ML
  1444 process.  New thread-based implementation also works on non-Unix
  1445 platforms (Cygwin).  Provers are no longer hardwired, but defined
  1446 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  1447 commands are covered in the isar-ref manual.
  1448 
  1449 * Wrapper scripts for remote SystemOnTPTP service allows to use
  1450 sledgehammer without local ATP installation (Vampire etc.). Other
  1451 provers may be included via suitable ML wrappers, see also
  1452 src/HOL/ATP_Linkup.thy.
  1453 
  1454 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  1455 menu.
  1456 
  1457 * The metis method no longer fails because the theorem is too trivial
  1458 (contains the empty clause).
  1459 
  1460 * The metis method now fails in the usual manner, rather than raising
  1461 an exception, if it determines that it cannot prove the theorem.
  1462 
  1463 * Method "coherent" implements a prover for coherent logic (see also
  1464 src/Tools/coherent.ML).
  1465 
  1466 * Constants "undefined" and "default" replace "arbitrary".  Usually
  1467 "undefined" is the right choice to replace "arbitrary", though
  1468 logically there is no difference.  INCOMPATIBILITY.
  1469 
  1470 * Command "value" now integrates different evaluation mechanisms.  The
  1471 result of the first successful evaluation mechanism is printed.  In
  1472 square brackets a particular named evaluation mechanisms may be
  1473 specified (currently, [SML], [code] or [nbe]).  See further
  1474 src/HOL/ex/Eval_Examples.thy.
  1475 
  1476 * Normalization by evaluation now allows non-leftlinear equations.
  1477 Declare with attribute [code nbe].
  1478 
  1479 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  1480 as the structured Isar versions "cases" and "induct", cf. the
  1481 corresponding "cases" and "induct" attributes.  Mutual induction rules
  1482 are now presented as a list of individual projections
  1483 (e.g. foo_bar.inducts for types foo and bar); the old format with
  1484 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  1485 rare situations a different rule is selected --- notably nested tuple
  1486 elimination instead of former prod.exhaust: use explicit (case_tac t
  1487 rule: prod.exhaust) here.
  1488 
  1489 * Attributes "cases", "induct", "coinduct" support "del" option.
  1490 
  1491 * Removed fact "case_split_thm", which duplicates "case_split".
  1492 
  1493 * The option datatype has been moved to a new theory Option.  Renamed
  1494 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  1495 
  1496 * New predicate "strict_mono" classifies strict functions on partial
  1497 orders.  With strict functions on linear orders, reasoning about
  1498 (in)equalities is facilitated by theorems "strict_mono_eq",
  1499 "strict_mono_less_eq" and "strict_mono_less".
  1500 
  1501 * Some set operations are now proper qualified constants with
  1502 authentic syntax.  INCOMPATIBILITY:
  1503 
  1504     op Int ~>   Set.Int
  1505     op Un ~>    Set.Un
  1506     INTER ~>    Set.INTER
  1507     UNION ~>    Set.UNION
  1508     Inter ~>    Set.Inter
  1509     Union ~>    Set.Union
  1510     {} ~>       Set.empty
  1511     UNIV ~>     Set.UNIV
  1512 
  1513 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  1514 theory Set.
  1515 
  1516 * Auxiliary class "itself" has disappeared -- classes without any
  1517 parameter are treated as expected by the 'class' command.
  1518 
  1519 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  1520 
  1521 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  1522 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  1523 
  1524 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  1525 method "approximation".  It proves formulas on real values by using
  1526 interval arithmetic.  In the formulas are also the transcendental
  1527 functions sin, cos, tan, atan, ln, exp and the constant pi are
  1528 allowed. For examples see
  1529 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  1530 
  1531 * Theory "Reflection" now resides in HOL/Library.
  1532 
  1533 * Entry point to Word library now simply named "Word".
  1534 INCOMPATIBILITY.
  1535 
  1536 * Made source layout more coherent with logical distribution
  1537 structure:
  1538 
  1539     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  1540     src/HOL/Library/Code_Message.thy ~> src/HOL/
  1541     src/HOL/Library/GCD.thy ~> src/HOL/
  1542     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  1543     src/HOL/Library/Parity.thy ~> src/HOL/
  1544     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  1545     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  1546     src/HOL/Real/Lubs.thy ~> src/HOL/
  1547     src/HOL/Real/PReal.thy ~> src/HOL/
  1548     src/HOL/Real/Rational.thy ~> src/HOL/
  1549     src/HOL/Real/RComplete.thy ~> src/HOL/
  1550     src/HOL/Real/RealDef.thy ~> src/HOL/
  1551     src/HOL/Real/RealPow.thy ~> src/HOL/
  1552     src/HOL/Real/Real.thy ~> src/HOL/
  1553     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  1554     src/HOL/Complex/Complex.thy ~> src/HOL/
  1555     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  1556     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  1557     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  1558     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  1559     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  1560     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  1561     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  1562     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  1563     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  1564     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  1565     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  1566     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  1567     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  1568     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  1569     src/HOL/Real/Float ~> src/HOL/Library/
  1570     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  1571     src/HOL/Real/RealVector.thy ~> src/HOL/
  1572 
  1573     src/HOL/arith_data.ML ~> src/HOL/Tools
  1574     src/HOL/hologic.ML ~> src/HOL/Tools
  1575     src/HOL/simpdata.ML ~> src/HOL/Tools
  1576     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  1577     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  1578     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  1579     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  1580     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  1581     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  1582     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  1583 
  1584     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  1585     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  1586     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  1587     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  1588     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  1589     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  1590 
  1591 * If methods "eval" and "evaluation" encounter a structured proof
  1592 state with !!/==>, only the conclusion is evaluated to True (if
  1593 possible), avoiding strange error messages.
  1594 
  1595 * Method "sizechange" automates termination proofs using (a
  1596 modification of) the size-change principle.  Requires SAT solver.  See
  1597 src/HOL/ex/Termination.thy for examples.
  1598 
  1599 * Simplifier: simproc for let expressions now unfolds if bound
  1600 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  1601 
  1602 * Method "arith": Linear arithmetic now ignores all inequalities when
  1603 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  1604 
  1605 * New attribute "arith" for facts that should always be used
  1606 automatically by arithmetic. It is intended to be used locally in
  1607 proofs, e.g.
  1608 
  1609   assumes [arith]: "x > 0"
  1610 
  1611 Global usage is discouraged because of possible performance impact.
  1612 
  1613 * New classes "top" and "bot" with corresponding operations "top" and
  1614 "bot" in theory Orderings; instantiation of class "complete_lattice"
  1615 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  1616 
  1617 * Changed definition lemma "less_fun_def" in order to provide an
  1618 instance for preorders on functions; use lemma "less_le" instead.
  1619 INCOMPATIBILITY.
  1620 
  1621 * Theory Orderings: class "wellorder" moved here, with explicit
  1622 induction rule "less_induct" as assumption.  For instantiation of
  1623 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  1624 INCOMPATIBILITY.
  1625 
  1626 * Theory Orderings: added class "preorder" as superclass of "order".
  1627 INCOMPATIBILITY: Instantiation proofs for order, linorder
  1628 etc. slightly changed.  Some theorems named order_class.* now named
  1629 preorder_class.*.
  1630 
  1631 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  1632 "diag" to "Id_on".
  1633 
  1634 * Theory Finite_Set: added a new fold combinator of type
  1635 
  1636   ('a => 'b => 'b) => 'b => 'a set => 'b
  1637 
  1638 Occasionally this is more convenient than the old fold combinator
  1639 which is now defined in terms of the new one and renamed to
  1640 fold_image.
  1641 
  1642 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  1643 and "ring_simps" have been replaced by "algebra_simps" (which can be
  1644 extended with further lemmas!).  At the moment both still exist but
  1645 the former will disappear at some point.
  1646 
  1647 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  1648 class recpower.  Type-specific simp rules for various recpower types
  1649 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  1650 
  1651 rat_power_0    -> power_0
  1652 rat_power_Suc  -> power_Suc
  1653 realpow_0      -> power_0
  1654 realpow_Suc    -> power_Suc
  1655 complexpow_0   -> power_0
  1656 complexpow_Suc -> power_Suc
  1657 power_poly_0   -> power_0
  1658 power_poly_Suc -> power_Suc
  1659 
  1660 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  1661 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  1662 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  1663 of lemmas from Divides has been generalized from nat to class
  1664 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  1665 renames resulting from duplicate elimination:
  1666 
  1667     dvd_def_mod ~>          dvd_eq_mod_eq_0
  1668     zero_dvd_iff ~>         dvd_0_left_iff
  1669     dvd_0 ~>                dvd_0_right
  1670     DIVISION_BY_ZERO_DIV ~> div_by_0
  1671     DIVISION_BY_ZERO_MOD ~> mod_by_0
  1672     mult_div ~>             div_mult_self2_is_id
  1673     mult_mod ~>             mod_mult_self2_is_0
  1674 
  1675 * Theory IntDiv: removed many lemmas that are instances of class-based
  1676 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  1677 rename old lemmas as follows:
  1678 
  1679 dvd_diff               -> nat_dvd_diff
  1680 dvd_zminus_iff         -> dvd_minus_iff
  1681 mod_add1_eq            -> mod_add_eq
  1682 mod_mult1_eq           -> mod_mult_right_eq
  1683 mod_mult1_eq'          -> mod_mult_left_eq
  1684 mod_mult_distrib_mod   -> mod_mult_eq
  1685 nat_mod_add_left_eq    -> mod_add_left_eq
  1686 nat_mod_add_right_eq   -> mod_add_right_eq
  1687 nat_mod_div_trivial    -> mod_div_trivial
  1688 nat_mod_mod_trivial    -> mod_mod_trivial
  1689 zdiv_zadd_self1        -> div_add_self1
  1690 zdiv_zadd_self2        -> div_add_self2
  1691 zdiv_zmult_self1       -> div_mult_self2_is_id
  1692 zdiv_zmult_self2       -> div_mult_self1_is_id
  1693 zdvd_triv_left         -> dvd_triv_left
  1694 zdvd_triv_right        -> dvd_triv_right
  1695 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  1696 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  1697 zmod_zadd_left_eq      -> mod_add_left_eq
  1698 zmod_zadd_right_eq     -> mod_add_right_eq
  1699 zmod_zadd_self1        -> mod_add_self1
  1700 zmod_zadd_self2        -> mod_add_self2
  1701 zmod_zadd1_eq          -> mod_add_eq
  1702 zmod_zdiff1_eq         -> mod_diff_eq
  1703 zmod_zdvd_zmod         -> mod_mod_cancel
  1704 zmod_zmod_cancel       -> mod_mod_cancel
  1705 zmod_zmult_self1       -> mod_mult_self2_is_0
  1706 zmod_zmult_self2       -> mod_mult_self1_is_0
  1707 zmod_1                 -> mod_by_1
  1708 zdiv_1                 -> div_by_1
  1709 zdvd_abs1              -> abs_dvd_iff
  1710 zdvd_abs2              -> dvd_abs_iff
  1711 zdvd_refl              -> dvd_refl
  1712 zdvd_trans             -> dvd_trans
  1713 zdvd_zadd              -> dvd_add
  1714 zdvd_zdiff             -> dvd_diff
  1715 zdvd_zminus_iff        -> dvd_minus_iff
  1716 zdvd_zminus2_iff       -> minus_dvd_iff
  1717 zdvd_zmultD            -> dvd_mult_right
  1718 zdvd_zmultD2           -> dvd_mult_left
  1719 zdvd_zmult_mono        -> mult_dvd_mono
  1720 zdvd_0_right           -> dvd_0_right
  1721 zdvd_0_left            -> dvd_0_left_iff
  1722 zdvd_1_left            -> one_dvd
  1723 zminus_dvd_iff         -> minus_dvd_iff
  1724 
  1725 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  1726 
  1727 * The real numbers offer decimal input syntax: 12.34 is translated
  1728 into 1234/10^2. This translation is not reversed upon output.
  1729 
  1730 * Theory Library/Polynomial defines an abstract type 'a poly of
  1731 univariate polynomials with coefficients of type 'a.  In addition to
  1732 the standard ring operations, it also supports div and mod.  Code
  1733 generation is also supported, using list-style constructors.
  1734 
  1735 * Theory Library/Inner_Product defines a class of real_inner for real
  1736 inner product spaces, with an overloaded operation inner :: 'a => 'a
  1737 => real.  Class real_inner is a subclass of real_normed_vector from
  1738 theory RealVector.
  1739 
  1740 * Theory Library/Product_Vector provides instances for the product
  1741 type 'a * 'b of several classes from RealVector and Inner_Product.
  1742 Definitions of addition, subtraction, scalar multiplication, norms,
  1743 and inner products are included.
  1744 
  1745 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  1746 addition to the field operations, numerals and case syntax are also
  1747 supported.
  1748 
  1749 * Theory Library/Diagonalize provides constructive version of Cantor's
  1750 first diagonalization argument.
  1751 
  1752 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  1753 zlcm (for int); carried together from various gcd/lcm developements in
  1754 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  1755 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  1756 may recover tupled syntax as follows:
  1757 
  1758     hide (open) const gcd
  1759     abbreviation gcd where
  1760       "gcd == (%(a, b). GCD.gcd a b)"
  1761     notation (output)
  1762       GCD.gcd ("gcd '(_, _')")
  1763 
  1764 The same works for lcm, zgcd, zlcm.
  1765 
  1766 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  1767 instantiations for algebraic structures.  Removed some duplicate
  1768 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  1769 
  1770 * ML antiquotation @{code} takes a constant as argument and generates
  1771 corresponding code in background and inserts name of the corresponding
  1772 resulting ML value/function/datatype constructor binding in place.
  1773 All occurrences of @{code} with a single ML block are generated
  1774 simultaneously.  Provides a generic and safe interface for
  1775 instrumentalizing code generation.  See
  1776 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  1777 In future you ought to refrain from ad-hoc compiling generated SML
  1778 code on the ML toplevel.  Note that (for technical reasons) @{code}
  1779 cannot refer to constants for which user-defined serializations are
  1780 set.  Refer to the corresponding ML counterpart directly in that
  1781 cases.
  1782 
  1783 * Command 'rep_datatype': instead of theorem names the command now
  1784 takes a list of terms denoting the constructors of the type to be
  1785 represented as datatype.  The characteristic theorems have to be
  1786 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  1787 have disappeared in favour of existing ones:
  1788 
  1789     unit_induct                 ~> unit.induct
  1790     prod_induct                 ~> prod.induct
  1791     sum_induct                  ~> sum.induct
  1792     Suc_Suc_eq                  ~> nat.inject
  1793     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  1794 
  1795 
  1796 *** HOL-Algebra ***
  1797 
  1798 * New locales for orders and lattices where the equivalence relation
  1799 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  1800 locales use a record structure with field eq for the equivalence.
  1801 
  1802 * New theory of factorial domains.
  1803 
  1804 * Units_l_inv and Units_r_inv are now simp rules by default.
  1805 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  1806 and/or r_inv will now also require deletion of these lemmas.
  1807 
  1808 * Renamed the following theorems, INCOMPATIBILITY:
  1809 
  1810 UpperD ~> Upper_memD
  1811 LowerD ~> Lower_memD
  1812 least_carrier ~> least_closed
  1813 greatest_carrier ~> greatest_closed
  1814 greatest_Lower_above ~> greatest_Lower_below
  1815 one_zero ~> carrier_one_zero
  1816 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  1817 
  1818 
  1819 *** HOL-Nominal ***
  1820 
  1821 * Nominal datatypes can now contain type-variables.
  1822 
  1823 * Commands 'nominal_inductive' and 'equivariance' work with local
  1824 theory targets.
  1825 
  1826 * Nominal primrec can now works with local theory targets and its
  1827 specification syntax now conforms to the general format as seen in
  1828 'inductive' etc.
  1829 
  1830 * Method "perm_simp" honours the standard simplifier attributes
  1831 (no_asm), (no_asm_use) etc.
  1832 
  1833 * The new predicate #* is defined like freshness, except that on the
  1834 left hand side can be a set or list of atoms.
  1835 
  1836 * Experimental command 'nominal_inductive2' derives strong induction
  1837 principles for inductive definitions.  In contrast to
  1838 'nominal_inductive', which can only deal with a fixed number of
  1839 binders, it can deal with arbitrary expressions standing for sets of
  1840 atoms to be avoided.  The only inductive definition we have at the
  1841 moment that needs this generalisation is the typing rule for Lets in
  1842 the algorithm W:
  1843 
  1844  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  1845  -----------------------------------------------------------------
  1846          Gamma |- Let x be t1 in t2 : T2
  1847 
  1848 In this rule one wants to avoid all the binders that are introduced by
  1849 "close Gamma T1".  We are looking for other examples where this
  1850 feature might be useful.  Please let us know.
  1851 
  1852 
  1853 *** HOLCF ***
  1854 
  1855 * Reimplemented the simplification procedure for proving continuity
  1856 subgoals.  The new simproc is extensible; users can declare additional
  1857 continuity introduction rules with the attribute [cont2cont].
  1858 
  1859 * The continuity simproc now uses a different introduction rule for
  1860 solving continuity subgoals on terms with lambda abstractions.  In
  1861 some rare cases the new simproc may fail to solve subgoals that the
  1862 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  1863 Potential INCOMPATIBILITY.
  1864 
  1865 * Command 'fixrec': specification syntax now conforms to the general
  1866 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  1867 examples.  INCOMPATIBILITY.
  1868 
  1869 
  1870 *** ZF ***
  1871 
  1872 * Proof of Zorn's Lemma for partial orders.
  1873 
  1874 
  1875 *** ML ***
  1876 
  1877 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  1878 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  1879 depends on multithreading, so timouts will not work before Poly/ML
  1880 5.2.1!
  1881 
  1882 * High-level support for concurrent ML programming, see
  1883 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  1884 particularly convenient to organize independent functional
  1885 computations.  The concept of "synchronized variables" provides a
  1886 higher-order interface for components with shared state, avoiding the
  1887 delicate details of mutexes and condition variables.  (Requires
  1888 Poly/ML 5.2.1 or later.)
  1889 
  1890 * ML bindings produced via Isar commands are stored within the Isar
  1891 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  1892 become thread-safe and work with undo as expected (concerning
  1893 top-level bindings, not side-effects on global references).
  1894 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  1895 compiler at runtime; really global bindings need to be given outside a
  1896 theory.  (Requires Poly/ML 5.2 or later.)
  1897 
  1898 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  1899 context.  Top-level ML bindings are stored within the proof context in
  1900 a purely sequential fashion, disregarding the nested proof structure.
  1901 ML bindings introduced by 'ML_prf' are discarded at the end of the
  1902 proof.  (Requires Poly/ML 5.2 or later.)
  1903 
  1904 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  1905 and Method.setup, as well as Isar commands 'attribute_setup' and
  1906 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  1907 existing code accordingly, or use plain 'setup' together with old
  1908 Method.add_method.
  1909 
  1910 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  1911 to 'a -> thm, while results are always tagged with an authentic oracle
  1912 name.  The Isar command 'oracle' is now polymorphic, no argument type
  1913 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  1914 accordingly.  Note that extra performance may be gained by producing
  1915 the cterm carefully, avoiding slow Thm.cterm_of.
  1916 
  1917 * Simplified interface for defining document antiquotations via
  1918 ThyOutput.antiquotation, ThyOutput.output, and optionally
  1919 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  1920 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  1921 examples.
  1922 
  1923 * More systematic treatment of long names, abstract name bindings, and
  1924 name space operations.  Basic operations on qualified names have been
  1925 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  1926 Long_Name.append.  Old type bstring has been mostly replaced by
  1927 abstract type binding (see structure Binding), which supports precise
  1928 qualification by packages and local theory targets, as well as proper
  1929 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  1930 bstring values into Binding.name, or better pass through abstract
  1931 bindings everywhere.  See further src/Pure/General/long_name.ML,
  1932 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  1933 
  1934 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  1935 LocalTheory.note etc.) now refer to the *full* internal name, not the
  1936 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  1937 
  1938 * Disposed old type and term read functions (Sign.read_def_typ,
  1939 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  1940 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  1941 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  1942 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  1943 resort for legacy applications.
  1944 
  1945 * Disposed old declarations, tactics, tactic combinators that refer to
  1946 the simpset or claset of an implicit theory (such as Addsimps,
  1947 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  1948 embedded ML text, or local_simpset_of with a proper context passed as
  1949 explicit runtime argument.
  1950 
  1951 * Rules and tactics that read instantiations (read_instantiate,
  1952 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  1953 context, which is required for parsing and type-checking.  Moreover,
  1954 the variables are specified as plain indexnames, not string encodings
  1955 thereof.  INCOMPATIBILITY.
  1956 
  1957 * Generic Toplevel.add_hook interface allows to analyze the result of
  1958 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  1959 for theorem dependency output of transactions resulting in a new
  1960 theory state.
  1961 
  1962 * ML antiquotations: block-structured compilation context indicated by
  1963 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  1964 
  1965   @{binding name}                         - basic name binding
  1966   @{let ?pat = term}                      - term abbreviation (HO matching)
  1967   @{note name = fact}                     - fact abbreviation
  1968   @{thm fact}                             - singleton fact (with attributes)
  1969   @{thms fact}                            - general fact (with attributes)
  1970   @{lemma prop by method}                 - singleton goal
  1971   @{lemma prop by meth1 meth2}            - singleton goal
  1972   @{lemma prop1 ... propN by method}      - general goal
  1973   @{lemma prop1 ... propN by meth1 meth2} - general goal
  1974   @{lemma (open) ...}                     - open derivation
  1975 
  1976 
  1977 *** System ***
  1978 
  1979 * The Isabelle "emacs" tool provides a specific interface to invoke
  1980 Proof General / Emacs, with more explicit failure if that is not
  1981 installed (the old isabelle-interface script silently falls back on
  1982 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  1983 installation location of the Proof General distribution.
  1984 
  1985 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  1986 the Isabelle process into a JVM/Scala application.  See
  1987 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  1988 process wrapper has been discontinued.)
  1989 
  1990 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  1991 
  1992 * Various status messages (with exact source position information) are
  1993 emitted, if proper markup print mode is enabled.  This allows
  1994 user-interface components to provide detailed feedback on internal
  1995 prover operations.
  1996 
  1997 
  1998 
  1999 New in Isabelle2008 (June 2008)
  2000 -------------------------------
  2001 
  2002 *** General ***
  2003 
  2004 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2005 and updated, with formally checked references as hyperlinks.
  2006 
  2007 * Theory loader: use_thy (and similar operations) no longer set the
  2008 implicit ML context, which was occasionally hard to predict and in
  2009 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2010 provides a proper context already.
  2011 
  2012 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2013 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2014 'use' within a theory file will do the job.
  2015 
  2016 * Name space merge now observes canonical order, i.e. the second space
  2017 is inserted into the first one, while existing entries in the first
  2018 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2019 swap theory imports.
  2020 
  2021 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2022 INCOMPATIBILITY in identifier syntax etc.
  2023 
  2024 * Outer syntax: string tokens no longer admit escaped white space,
  2025 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2026 white space without escapes.
  2027 
  2028 * Outer syntax: string tokens may contain arbitrary character codes
  2029 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2030 "foo_bar".
  2031 
  2032 
  2033 *** Pure ***
  2034 
  2035 * Context-dependent token translations.  Default setup reverts locally
  2036 fixed variables, and adds hilite markup for undeclared frees.
  2037 
  2038 * Unused theorems can be found using the new command 'unused_thms'.
  2039 There are three ways of invoking it:
  2040 
  2041 (1) unused_thms
  2042      Only finds unused theorems in the current theory.
  2043 
  2044 (2) unused_thms thy_1 ... thy_n -
  2045      Finds unused theorems in the current theory and all of its ancestors,
  2046      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2047 
  2048 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2049      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2050      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2051      their ancestors.
  2052 
  2053 In order to increase the readability of the list produced by
  2054 unused_thms, theorems that have been created by a particular instance
  2055 of a theory command such as 'inductive' or 'function' are considered
  2056 to belong to the same "group", meaning that if at least one theorem in
  2057 this group is used, the other theorems in the same group are no longer
  2058 reported as unused.  Moreover, if all theorems in the group are
  2059 unused, only one theorem in the group is displayed.
  2060 
  2061 Note that proof objects have to be switched on in order for
  2062 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2063 usually the case when using Proof General with the default settings).
  2064 
  2065 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2066 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2067 duplicate fact bindings, or even accidental fact duplications.  Note
  2068 that tools may maintain dynamically scoped facts systematically, using
  2069 PureThy.add_thms_dynamic.
  2070 
  2071 * Command 'hide' now allows to hide from "fact" name space as well.
  2072 
  2073 * Eliminated destructive theorem database, simpset, claset, and
  2074 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2075 update of theories within ML code.
  2076 
  2077 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2078 INCOMPATIBILITY, object-logics depending on former Pure require
  2079 additional setup PureThy.old_appl_syntax_setup; object-logics
  2080 depending on former CPure need to refer to Pure.
  2081 
  2082 * Commands 'use' and 'ML' are now purely functional, operating on
  2083 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2084 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2085 INCOMPATIBILITY.
  2086 
  2087 * Command 'setup': discontinued implicit version with ML reference.
  2088 
  2089 * Instantiation target allows for simultaneous specification of class
  2090 instance operations together with an instantiation proof.
  2091 Type-checking phase allows to refer to class operations uniformly.
  2092 See src/HOL/Complex/Complex.thy for an Isar example and
  2093 src/HOL/Library/Eval.thy for an ML example.
  2094 
  2095 * Indexing of literal facts: be more serious about including only
  2096 facts from the visible specification/proof context, but not the
  2097 background context (locale etc.).  Affects `prop` notation and method
  2098 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2099 situations.
  2100 
  2101 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2102 "(open)" option, which used to expose internal bound variables to the
  2103 proof text.
  2104 
  2105 * Isar statements: removed obsolete case "rule_context".
  2106 INCOMPATIBILITY, better use explicit fixes/assumes.
  2107 
  2108 * Locale proofs: default proof step now includes 'unfold_locales';
  2109 hence 'proof' without argument may be used to unfold locale
  2110 predicates.
  2111 
  2112 
  2113 *** Document preparation ***
  2114 
  2115 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2116 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2117 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2118 spot); renamed link color from "darkblue" to "linkcolor" (default
  2119 value unchanged, can be redefined via \definecolor); no longer sets
  2120 "a4paper" option (unnecessary or even intrusive).
  2121 
  2122 * Antiquotation @{lemma A method} proves proposition A by the given
  2123 method (either a method name or a method name plus (optional) method
  2124 arguments in parentheses) and prints A just like @{prop A}.
  2125 
  2126 
  2127 *** HOL ***
  2128 
  2129 * New primrec package.  Specification syntax conforms in style to
  2130 definition/function/....  No separate induction rule is provided.  The
  2131 "primrec" command distinguishes old-style and new-style specifications
  2132 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2133 When adjusting theories, beware: constants stemming from new-style
  2134 primrec specifications have authentic syntax.
  2135 
  2136 * Metis prover is now an order of magnitude faster, and also works
  2137 with multithreading.
  2138 
  2139 * Metis: the maximum number of clauses that can be produced from a
  2140 theorem is now given by the attribute max_clauses.  Theorems that
  2141 exceed this number are ignored, with a warning printed.
  2142 
  2143 * Sledgehammer no longer produces structured proofs by default. To
  2144 enable, declare [[sledgehammer_full = true]].  Attributes
  2145 reconstruction_modulus, reconstruction_sorts renamed
  2146 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2147 
  2148 * Method "induct_scheme" derives user-specified induction rules
  2149 from well-founded induction and completeness of patterns. This factors
  2150 out some operations that are done internally by the function package
  2151 and makes them available separately.  See
  2152 src/HOL/ex/Induction_Scheme.thy for examples.
  2153 
  2154 * More flexible generation of measure functions for termination
  2155 proofs: Measure functions can be declared by proving a rule of the
  2156 form "is_measure f" and giving it the [measure_function] attribute.
  2157 The "is_measure" predicate is logically meaningless (always true), and
  2158 just guides the heuristic.  To find suitable measure functions, the
  2159 termination prover sets up the goal "is_measure ?f" of the appropriate
  2160 type and generates all solutions by prolog-style backwards proof using
  2161 the declared rules.
  2162 
  2163 This setup also deals with rules like 
  2164 
  2165   "is_measure f ==> is_measure (list_size f)"
  2166 
  2167 which accommodates nested datatypes that recurse through lists.
  2168 Similar rules are predeclared for products and option types.
  2169 
  2170 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2171 
  2172   INCOMPATIBILITIES:
  2173 
  2174   - Definitions of overloaded constants on sets have to be replaced by
  2175     definitions on => and bool.
  2176 
  2177   - Some definitions of overloaded operators on sets can now be proved
  2178     using the definitions of the operators on => and bool.  Therefore,
  2179     the following theorems have been renamed:
  2180 
  2181       subset_def   -> subset_eq
  2182       psubset_def  -> psubset_eq
  2183       set_diff_def -> set_diff_eq
  2184       Compl_def    -> Compl_eq
  2185       Sup_set_def  -> Sup_set_eq
  2186       Inf_set_def  -> Inf_set_eq
  2187       sup_set_def  -> sup_set_eq
  2188       inf_set_def  -> inf_set_eq
  2189 
  2190   - Due to the incompleteness of the HO unification algorithm, some
  2191     rules such as subst may require manual instantiation, if some of
  2192     the unknowns in the rule is a set.
  2193 
  2194   - Higher order unification and forward proofs:
  2195     The proof pattern
  2196 
  2197       have "P (S::'a set)" <...>
  2198       then have "EX S. P S" ..
  2199 
  2200     no longer works (due to the incompleteness of the HO unification
  2201     algorithm) and must be replaced by the pattern
  2202 
  2203       have "EX S. P S"
  2204       proof
  2205         show "P S" <...>
  2206       qed
  2207 
  2208   - Calculational reasoning with subst (or similar rules):
  2209     The proof pattern
  2210 
  2211       have "P (S::'a set)" <...>
  2212       also have "S = T" <...>
  2213       finally have "P T" .
  2214 
  2215     no longer works (for similar reasons as the previous example) and
  2216     must be replaced by something like
  2217 
  2218       have "P (S::'a set)" <...>
  2219       moreover have "S = T" <...>
  2220       ultimately have "P T" by simp
  2221 
  2222   - Tactics or packages written in ML code:
  2223     Code performing pattern matching on types via
  2224 
  2225       Type ("set", [T]) => ...
  2226 
  2227     must be rewritten. Moreover, functions like strip_type or
  2228     binder_types no longer return the right value when applied to a
  2229     type of the form
  2230 
  2231       T1 => ... => Tn => U => bool
  2232 
  2233     rather than
  2234 
  2235       T1 => ... => Tn => U set
  2236 
  2237 * Merged theories Wellfounded_Recursion, Accessible_Part and
  2238 Wellfounded_Relations to theory Wellfounded.
  2239 
  2240 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  2241 
  2242 * Class finite no longer treats UNIV as class parameter.  Use class
  2243 enum from theory Library/Enum instead to achieve a similar effect.
  2244 INCOMPATIBILITY.
  2245 
  2246 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  2247 and "Cons".  INCOMPATIBILITY.
  2248 
  2249 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  2250 Potential INCOMPATIBILITY.
  2251 
  2252 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  2253 injective_fst_snd removed, use split_eta and prod_eqI instead.
  2254 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  2255 
  2256 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  2257 the same name in theory Orderings:
  2258 
  2259   less_trans
  2260   less_linear
  2261   le_imp_less_or_eq
  2262   le_less_trans
  2263   less_le_trans
  2264   less_not_sym
  2265   less_asym
  2266 
  2267 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  2268 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  2269 and different variable names.
  2270 
  2271 * Library/Option_ord.thy: Canonical order on option type.
  2272 
  2273 * Library/RBT.thy: Red-black trees, an efficient implementation of
  2274 finite maps.
  2275 
  2276 * Library/Countable.thy: Type class for countable types.
  2277 
  2278 * Theory Int: The representation of numerals has changed.  The infix
  2279 operator BIT and the bit datatype with constructors B0 and B1 have
  2280 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  2281 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  2282 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  2283 accordingly.
  2284 
  2285 * Theory Nat: definition of <= and < on natural numbers no longer
  2286 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  2287 le_def and less_def have disappeared.  Consider lemmas not_less
  2288 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  2289 
  2290 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  2291 (whose purpose mainly is for various fold_set functionals) have been
  2292 abandoned in favor of the existing algebraic classes
  2293 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  2294 lower_semilattice (resp. upper_semilattice) and linorder.
  2295 INCOMPATIBILITY.
  2296 
  2297 * Theory Transitive_Closure: induct and cases rules now declare proper
  2298 case_names ("base" and "step").  INCOMPATIBILITY.
  2299 
  2300 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  2301 lattices.  The form set-specific version is available as
  2302 Inductive.lfp_ordinal_induct_set.
  2303 
  2304 * Renamed theorems "power.simps" to "power_int.simps".
  2305 INCOMPATIBILITY.
  2306 
  2307 * Class semiring_div provides basic abstract properties of semirings
  2308 with division and modulo operations.  Subsumes former class dvd_mod.
  2309 
  2310 * Merged theories IntDef, Numeral and IntArith into unified theory
  2311 Int.  INCOMPATIBILITY.
  2312 
  2313 * Theory Library/Code_Index: type "index" now represents natural
  2314 numbers rather than integers.  INCOMPATIBILITY.
  2315 
  2316 * New class "uminus" with operation "uminus" (split of from class
  2317 "minus" which now only has operation "minus", binary).
  2318 INCOMPATIBILITY.
  2319 
  2320 * Constants "card", "internal_split", "option_map" now with authentic
  2321 syntax.  INCOMPATIBILITY.
  2322 
  2323 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  2324 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  2325 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  2326 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  2327 Sup_set_def, le_def, less_def, option_map_def now with object
  2328 equality.  INCOMPATIBILITY.
  2329 
  2330 * Records. Removed K_record, and replaced it by pure lambda term
  2331 %x. c. The simplifier setup is now more robust against eta expansion.
  2332 INCOMPATIBILITY: in cases explicitly referring to K_record.
  2333 
  2334 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  2335 
  2336 * Library/ListVector: new theory of arithmetic vector operations.
  2337 
  2338 * Library/Order_Relation: new theory of various orderings as sets of
  2339 pairs.  Defines preorders, partial orders, linear orders and
  2340 well-orders on sets and on types.
  2341 
  2342 
  2343 *** ZF ***
  2344 
  2345 * Renamed some theories to allow to loading both ZF and HOL in the
  2346 same session:
  2347 
  2348   Datatype  -> Datatype_ZF
  2349   Inductive -> Inductive_ZF
  2350   Int       -> Int_ZF
  2351   IntDiv    -> IntDiv_ZF
  2352   Nat       -> Nat_ZF
  2353   List      -> List_ZF
  2354   Main      -> Main_ZF
  2355 
  2356 INCOMPATIBILITY: ZF theories that import individual theories below
  2357 Main might need to be adapted.  Regular theory Main is still
  2358 available, as trivial extension of Main_ZF.
  2359 
  2360 
  2361 *** ML ***
  2362 
  2363 * ML within Isar: antiquotation @{const name} or @{const
  2364 name(typargs)} produces statically-checked Const term.
  2365 
  2366 * Functor NamedThmsFun: data is available to the user as dynamic fact
  2367 (of the same name).  Removed obsolete print command.
  2368 
  2369 * Removed obsolete "use_legacy_bindings" function.
  2370 
  2371 * The ``print mode'' is now a thread-local value derived from a global
  2372 template (the former print_mode reference), thus access becomes
  2373 non-critical.  The global print_mode reference is for session
  2374 management only; user-code should use print_mode_value,
  2375 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  2376 
  2377 * Functions system/system_out provide a robust way to invoke external
  2378 shell commands, with propagation of interrupts (requires Poly/ML
  2379 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  2380 
  2381 
  2382 *** System ***
  2383 
  2384 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  2385 in accordance with Proof General 3.7, which prefers GNU emacs.
  2386 
  2387 * isatool tty runs Isabelle process with plain tty interaction;
  2388 optional line editor may be specified via ISABELLE_LINE_EDITOR
  2389 setting, the default settings attempt to locate "ledit" and "rlwrap".
  2390 
  2391 * isatool browser now works with Cygwin as well, using general
  2392 "javapath" function defined in Isabelle process environment.
  2393 
  2394 * YXML notation provides a simple and efficient alternative to
  2395 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  2396 isatool yxml as described in the Isabelle system manual.
  2397 
  2398 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  2399 provides general wrapper for managing an Isabelle process in a robust
  2400 fashion, with ``cooked'' output from stdin/stderr.
  2401 
  2402 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  2403 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  2404 
  2405 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  2406 way of changing the user's settings is via
  2407 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  2408 script.
  2409 
  2410 * Multithreading.max_threads := 0 refers to the number of actual CPU
  2411 cores of the underlying machine, which is a good starting point for
  2412 optimal performance tuning.  The corresponding usedir option -M allows
  2413 "max" as an alias for "0".  WARNING: does not work on certain versions
  2414 of Mac OS (with Poly/ML 5.1).
  2415 
  2416 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  2417 adverse effect of Isabelle flooding interactive front-ends (notably
  2418 ProofGeneral / XEmacs).
  2419 
  2420 
  2421 
  2422 New in Isabelle2007 (November 2007)
  2423 -----------------------------------
  2424 
  2425 *** General ***
  2426 
  2427 * More uniform information about legacy features, notably a
  2428 warning/error of "Legacy feature: ...", depending on the state of the
  2429 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  2430 legacy features will disappear eventually.
  2431 
  2432 * Theory syntax: the header format ``theory A = B + C:'' has been
  2433 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  2434 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  2435 
  2436 * Theory syntax: the old non-Isar theory file format has been
  2437 discontinued altogether.  Note that ML proof scripts may still be used
  2438 with Isar theories; migration is usually quite simple with the ML
  2439 function use_legacy_bindings.  INCOMPATIBILITY.
  2440 
  2441 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  2442 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  2443 quotes.
  2444 
  2445 * Theory loader: be more serious about observing the static theory
  2446 header specifications (including optional directories), but not the
  2447 accidental file locations of previously successful loads.  The strict
  2448 update policy of former update_thy is now already performed by
  2449 use_thy, so the former has been removed; use_thys updates several
  2450 theories simultaneously, just as 'imports' within a theory header
  2451 specification, but without merging the results.  Potential
  2452 INCOMPATIBILITY: may need to refine theory headers and commands
  2453 ROOT.ML which depend on load order.
  2454 
  2455 * Theory loader: optional support for content-based file
  2456 identification, instead of the traditional scheme of full physical
  2457 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  2458 (cf. the system manual).  The new scheme allows to work with
  2459 non-finished theories in persistent session images, such that source
  2460 files may be moved later on without requiring reloads.
  2461 
  2462 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2463 file (with the same base name as the theory) are considered a legacy
  2464 feature, which will disappear eventually. Even now, the theory loader
  2465 no longer maintains dependencies on such files.
  2466 
  2467 * Syntax: the scope for resolving ambiguities via type-inference is
  2468 now limited to individual terms, instead of whole simultaneous
  2469 specifications as before. This greatly reduces the complexity of the
  2470 syntax module and improves flexibility by separating parsing and
  2471 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  2472 'fixes' etc.) are required in rare situations.
  2473 
  2474 * Syntax: constants introduced by new-style packages ('definition',
  2475 'abbreviation' etc.) are passed through the syntax module in
  2476 ``authentic mode''. This means that associated mixfix annotations
  2477 really stick to such constants, independently of potential name space
  2478 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  2479 trees are represented slightly differently, may need to adapt syntax
  2480 translations accordingly. Use CONST marker in 'translations' and
  2481 @{const_syntax} antiquotation in 'parse_translation' etc.
  2482 
  2483 * Legacy goal package: reduced interface to the bare minimum required
  2484 to keep existing proof scripts running.  Most other user-level
  2485 functions are now part of the OldGoals structure, which is *not* open
  2486 by default (consider isatool expandshort before open OldGoals).
  2487 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  2488 these tend to cause confusion about the actual goal (!) context being
  2489 used here, which is not necessarily the same as the_context().
  2490 
  2491 * Command 'find_theorems': supports "*" wild-card in "name:"
  2492 criterion; "with_dups" option.  Certain ProofGeneral versions might
  2493 support a specific search form (see ProofGeneral/CHANGES).
  2494 
  2495 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  2496 by default, which means that "prems" (and also "fixed variables") are
  2497 suppressed from proof state output.  Note that the ProofGeneral
  2498 settings mechanism allows to change and save options persistently, but
  2499 older versions of Isabelle will fail to start up if a negative prems
  2500 limit is imposed.
  2501 
  2502 * Local theory targets may be specified by non-nested blocks of
  2503 ``context/locale/class ... begin'' followed by ``end''.  The body may
  2504 contain definitions, theorems etc., including any derived mechanism
  2505 that has been implemented on top of these primitives.  This concept
  2506 generalizes the existing ``theorem (in ...)'' towards more versatility
  2507 and scalability.
  2508 
  2509 * Proof General interface: proper undo of final 'end' command;
  2510 discontinued Isabelle/classic mode (ML proof scripts).
  2511 
  2512 
  2513 *** Document preparation ***
  2514 
  2515 * Added antiquotation @{theory name} which prints the given name,
  2516 after checking that it refers to a valid ancestor theory in the
  2517 current context.
  2518 
  2519 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  2520 check the given source text as ML type/structure, printing verbatim.
  2521 
  2522 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  2523 "c args == rhs" given in the current context.  (Any number of
  2524 arguments may be given on the LHS.)
  2525 
  2526 
  2527 *** Pure ***
  2528 
  2529 * The 'class' package offers a combination of axclass and locale to
  2530 achieve Haskell-like type classes in Isabelle.  Definitions and
  2531 theorems within a class context produce both relative results (with
  2532 implicit parameters according to the locale context), and polymorphic
  2533 constants with qualified polymorphism (according to the class
  2534 context).  Within the body context of a 'class' target, a separate
  2535 syntax layer ("user space type system") takes care of converting
  2536 between global polymorphic consts and internal locale representation.
  2537 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  2538 "isatool doc classes" provides a tutorial.
  2539 
  2540 * Generic code generator framework allows to generate executable
  2541 code for ML and Haskell (including Isabelle classes).  A short usage
  2542 sketch:
  2543 
  2544     internal compilation:
  2545         export_code <list of constants (term syntax)> in SML
  2546     writing SML code to a file:
  2547         export_code <list of constants (term syntax)> in SML <filename>
  2548     writing OCaml code to a file:
  2549         export_code <list of constants (term syntax)> in OCaml <filename>
  2550     writing Haskell code to a bunch of files:
  2551         export_code <list of constants (term syntax)> in Haskell <filename>
  2552 
  2553     evaluating closed propositions to True/False using code generation:
  2554         method ``eval''
  2555 
  2556 Reasonable default setup of framework in HOL.
  2557 
  2558 Theorem attributs for selecting and transforming function equations theorems:
  2559 
  2560     [code fun]:        select a theorem as function equation for a specific constant
  2561     [code fun del]:    deselect a theorem as function equation for a specific constant
  2562     [code inline]:     select an equation theorem for unfolding (inlining) in place
  2563     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  2564 
  2565 User-defined serializations (target in {SML, OCaml, Haskell}):
  2566 
  2567     code_const <and-list of constants (term syntax)>
  2568       {(target) <and-list of const target syntax>}+
  2569 
  2570     code_type <and-list of type constructors>
  2571       {(target) <and-list of type target syntax>}+
  2572 
  2573     code_instance <and-list of instances>
  2574       {(target)}+
  2575         where instance ::= <type constructor> :: <class>
  2576 
  2577     code_class <and_list of classes>
  2578       {(target) <and-list of class target syntax>}+
  2579         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  2580 
  2581 code_instance and code_class only are effective to target Haskell.
  2582 
  2583 For example usage see src/HOL/ex/Codegenerator.thy and
  2584 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  2585 generation from Isabelle/HOL theories is available via "isatool doc
  2586 codegen".
  2587 
  2588 * Code generator: consts in 'consts_code' Isar commands are now
  2589 referred to by usual term syntax (including optional type
  2590 annotations).
  2591 
  2592 * Command 'no_translations' removes translation rules from theory
  2593 syntax.
  2594 
  2595 * Overloaded definitions are now actually checked for acyclic
  2596 dependencies.  The overloading scheme is slightly more general than
  2597 that of Haskell98, although Isabelle does not demand an exact
  2598 correspondence to type class and instance declarations.
  2599 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  2600 exotic versions of overloading -- at the discretion of the user!
  2601 
  2602 Polymorphic constants are represented via type arguments, i.e. the
  2603 instantiation that matches an instance against the most general
  2604 declaration given in the signature.  For example, with the declaration
  2605 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  2606 as c(nat).  Overloading is essentially simultaneous structural
  2607 recursion over such type arguments.  Incomplete specification patterns
  2608 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  2609 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  2610 Command 'print_theory' outputs the normalized system of recursive
  2611 equations, see section "definitions".
  2612 
  2613 * Configuration options are maintained within the theory or proof
  2614 context (with name and type bool/int/string), providing a very simple
  2615 interface to a poor-man's version of general context data.  Tools may
  2616 declare options in ML (e.g. using Attrib.config_int) and then refer to
  2617 these values using Config.get etc.  Users may change options via an
  2618 associated attribute of the same name.  This form of context
  2619 declaration works particularly well with commands 'declare' or
  2620 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  2621 very easy to avoid global references, which would not observe Isar
  2622 toplevel undo/redo and fail to work with multithreading.
  2623 
  2624 Various global ML references of Pure and HOL have been turned into
  2625 configuration options:
  2626 
  2627   Unify.search_bound		unify_search_bound
  2628   Unify.trace_bound		unify_trace_bound
  2629   Unify.trace_simp		unify_trace_simp
  2630   Unify.trace_types		unify_trace_types
  2631   Simplifier.simp_depth_limit	simp_depth_limit
  2632   Blast.depth_limit		blast_depth_limit
  2633   DatatypeProp.dtK		datatype_distinctness_limit
  2634   fast_arith_neq_limit  	fast_arith_neq_limit
  2635   fast_arith_split_limit	fast_arith_split_limit
  2636 
  2637 * Named collections of theorems may be easily installed as context
  2638 data using the functor NamedThmsFun (see also
  2639 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  2640 attributes; there is also a toplevel print command.  This facility is
  2641 just a common case of general context data, which is the preferred way
  2642 for anything more complex than just a list of facts in canonical
  2643 order.
  2644 
  2645 * Isar: command 'declaration' augments a local theory by generic
  2646 declaration functions written in ML.  This enables arbitrary content
  2647 being added to the context, depending on a morphism that tells the
  2648 difference of the original declaration context wrt. the application
  2649 context encountered later on.
  2650 
  2651 * Isar: proper interfaces for simplification procedures.  Command
  2652 'simproc_setup' declares named simprocs (with match patterns, and body
  2653 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  2654 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  2655 
  2656 * Isar: an extra pair of brackets around attribute declarations
  2657 abbreviates a theorem reference involving an internal dummy fact,
  2658 which will be ignored later --- only the effect of the attribute on
  2659 the background context will persist.  This form of in-place
  2660 declarations is particularly useful with commands like 'declare' and
  2661 'using', for example ``have A using [[simproc a]] by simp''.
  2662 
  2663 * Isar: method "assumption" (and implicit closing of subproofs) now
  2664 takes simple non-atomic goal assumptions into account: after applying
  2665 an assumption as a rule the resulting subgoals are solved by atomic
  2666 assumption steps.  This is particularly useful to finish 'obtain'
  2667 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  2668 without referring to the original premise "!!x. P x ==> thesis" in the
  2669 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  2670 more permissive.
  2671 
  2672 * Isar: implicit use of prems from the Isar proof context is
  2673 considered a legacy feature.  Common applications like ``have A .''
  2674 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  2675 referencing facts explicitly here improves readability and
  2676 maintainability of proof texts.
  2677 
  2678 * Isar: improper proof element 'guess' is like 'obtain', but derives
  2679 the obtained context from the course of reasoning!  For example:
  2680 
  2681   assume "EX x y. A x & B y"   -- "any previous fact"
  2682   then guess x and y by clarify
  2683 
  2684 This technique is potentially adventurous, depending on the facts and
  2685 proof tools being involved here.
  2686 
  2687 * Isar: known facts from the proof context may be specified as literal
  2688 propositions, using ASCII back-quote syntax.  This works wherever
  2689 named facts used to be allowed so far, in proof commands, proof
  2690 methods, attributes etc.  Literal facts are retrieved from the context
  2691 according to unification of type and term parameters.  For example,
  2692 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  2693 theorems in the current context, then these are valid literal facts:
  2694 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  2695 
  2696 There is also a proof method "fact" which does the same composition
  2697 for explicit goal states, e.g. the following proof texts coincide with
  2698 certain special cases of literal facts:
  2699 
  2700   have "A" by fact                 ==  note `A`
  2701   have "A ==> B" by fact           ==  note `A ==> B`
  2702   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  2703   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  2704 
  2705 * Isar: ":" (colon) is no longer a symbolic identifier character in
  2706 outer syntax.  Thus symbolic identifiers may be used without
  2707 additional white space in declarations like this: ``assume *: A''.
  2708 
  2709 * Isar: 'print_facts' prints all local facts of the current context,
  2710 both named and unnamed ones.
  2711 
  2712 * Isar: 'def' now admits simultaneous definitions, e.g.:
  2713 
  2714   def x == "t" and y == "u"
  2715 
  2716 * Isar: added command 'unfolding', which is structurally similar to
  2717 'using', but affects both the goal state and facts by unfolding given
  2718 rewrite rules.  Thus many occurrences of the 'unfold' method or
  2719 'unfolded' attribute may be replaced by first-class proof text.
  2720 
  2721 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  2722 and command 'unfolding' now all support object-level equalities
  2723 (potentially conditional).  The underlying notion of rewrite rule is
  2724 analogous to the 'rule_format' attribute, but *not* that of the
  2725 Simplifier (which is usually more generous).
  2726 
  2727 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  2728 premises of a theorem by n. Useful in conjunction with drule.
  2729 
  2730 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  2731 method expression within a sandbox consisting of the first N
  2732 sub-goals, which need to exist.  For example, ``simp_all [3]''
  2733 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  2734 simplifies all new goals that emerge from applying rule foo to the
  2735 originally first one.
  2736 
  2737 * Isar: schematic goals are no longer restricted to higher-order
  2738 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  2739 expected.
  2740 
  2741 * Isar: the conclusion of a long theorem statement is now either
  2742 'shows' (a simultaneous conjunction, as before), or 'obtains'
  2743 (essentially a disjunction of cases with local parameters and
  2744 assumptions).  The latter allows to express general elimination rules
  2745 adequately; in this notation common elimination rules look like this:
  2746 
  2747   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  2748     assumes "EX x. P x"
  2749     obtains x where "P x"
  2750 
  2751   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  2752     assumes "A & B"
  2753     obtains A and B
  2754 
  2755   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  2756     assumes "A | B"
  2757     obtains
  2758       A
  2759     | B
  2760 
  2761 The subsequent classical rules even refer to the formal "thesis"
  2762 explicitly:
  2763 
  2764   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  2765     obtains "~ thesis"
  2766 
  2767   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  2768     obtains "thesis ==> something"
  2769 
  2770 The actual proof of an 'obtains' statement is analogous to that of the
  2771 Isar proof element 'obtain', only that there may be several cases.
  2772 Optional case names may be specified in parentheses; these will be
  2773 available both in the present proof and as annotations in the
  2774 resulting rule, for later use with the 'cases' method (cf. attribute
  2775 case_names).
  2776 
  2777 * Isar: the assumptions of a long theorem statement are available as
  2778 "assms" fact in the proof context.  This is more appropriate than the
  2779 (historical) "prems", which refers to all assumptions of the current
  2780 context, including those from the target locale, proof body etc.
  2781 
  2782 * Isar: 'print_statement' prints theorems from the current theory or
  2783 proof context in long statement form, according to the syntax of a
  2784 top-level lemma.
  2785 
  2786 * Isar: 'obtain' takes an optional case name for the local context
  2787 introduction rule (default "that").
  2788 
  2789 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  2790 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  2791 to occur.
  2792 
  2793 * Pure: syntax "CONST name" produces a fully internalized constant
  2794 according to the current context.  This is particularly useful for
  2795 syntax translations that should refer to internal constant
  2796 representations independently of name spaces.
  2797 
  2798 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  2799 instead of "FOO ". This allows multiple binder declarations to coexist
  2800 in the same context.  INCOMPATIBILITY.
  2801 
  2802 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  2803 primitive that also works in a locale context (both for constants and
  2804 fixed variables). Type declaration and internal syntactic representation
  2805 of given constants retrieved from the context. Likewise, the
  2806 'no_notation' command allows to remove given syntax annotations from the
  2807 current context.
  2808 
  2809 * Isar/locales: new derived specification elements 'axiomatization',
  2810 'definition', 'abbreviation', which support type-inference, admit
  2811 object-level specifications (equality, equivalence).  See also the
  2812 isar-ref manual.  Examples:
  2813 
  2814   axiomatization
  2815     eq  (infix "===" 50) where
  2816     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  2817 
  2818   definition "f x y = x + y + 1"
  2819   definition g where "g x = f x x"
  2820 
  2821   abbreviation
  2822     neq  (infix "=!=" 50) where
  2823     "x =!= y == ~ (x === y)"
  2824 
  2825 These specifications may be also used in a locale context.  Then the
  2826 constants being introduced depend on certain fixed parameters, and the
  2827 constant name is qualified by the locale base name.  An internal
  2828 abbreviation takes care for convenient input and output, making the
  2829 parameters implicit and using the original short name.  See also
  2830 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  2831 entities from a monomorphic theory.
  2832 
  2833 Presently, abbreviations are only available 'in' a target locale, but
  2834 not inherited by general import expressions.  Also note that
  2835 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  2836 'translations' in common applications.  The "no_abbrevs" print mode
  2837 prevents folding of abbreviations in term output.
  2838 
  2839 Concrete syntax is attached to specified constants in internal form,
  2840 independently of name spaces.  The parse tree representation is
  2841 slightly different -- use 'notation' instead of raw 'syntax', and
  2842 'translations' with explicit "CONST" markup to accommodate this.
  2843 
  2844 * Pure/Isar: unified syntax for new-style specification mechanisms
  2845 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  2846 full type inference and dummy patterns ("_").  For example:
  2847 
  2848   definition "K x _ = x"
  2849 
  2850   inductive conj for A B
  2851   where "A ==> B ==> conj A B"
  2852 
  2853 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  2854 the current context.  Print mode "no_abbrevs" prevents inversion of
  2855 abbreviations on output.
  2856 
  2857 * Isar/locales: improved parameter handling: use of locales "var" and
  2858 "struct" no longer necessary; - parameter renamings are no longer
  2859 required to be injective.  For example, this allows to define
  2860 endomorphisms as locale endom = homom mult mult h.
  2861 
  2862 * Isar/locales: changed the way locales with predicates are defined.
  2863 Instead of accumulating the specification, the imported expression is
  2864 now an interpretation.  INCOMPATIBILITY: different normal form of
  2865 locale expressions.  In particular, in interpretations of locales with
  2866 predicates, goals repesenting already interpreted fragments are not
  2867 removed automatically.  Use methods `intro_locales' and
  2868 `unfold_locales'; see below.
  2869 
  2870 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  2871 provide backward reasoning on locales predicates.  The methods are
  2872 aware of interpretations and discharge corresponding goals.
  2873 `intro_locales' is less aggressive then `unfold_locales' and does not
  2874 unfold predicates to assumptions.
  2875 
  2876 * Isar/locales: the order in which locale fragments are accumulated
  2877 has changed.  This enables to override declarations from fragments due
  2878 to interpretations -- for example, unwanted simp rules.
  2879 
  2880 * Isar/locales: interpretation in theories and proof contexts has been
  2881 extended.  One may now specify (and prove) equations, which are
  2882 unfolded in interpreted theorems.  This is useful for replacing
  2883 defined concepts (constants depending on locale parameters) by
  2884 concepts already existing in the target context.  Example:
  2885 
  2886   interpretation partial_order ["op <= :: [int, int] => bool"]
  2887     where "partial_order.less (op <=) (x::int) y = (x < y)"
  2888 
  2889 Typically, the constant `partial_order.less' is created by a
  2890 definition specification element in the context of locale
  2891 partial_order.
  2892 
  2893 * Method "induct": improved internal context management to support
  2894 local fixes and defines on-the-fly. Thus explicit meta-level
  2895 connectives !!  and ==> are rarely required anymore in inductive goals
  2896 (using object-logic connectives for this purpose has been long
  2897 obsolete anyway). Common proof patterns are explained in
  2898 src/HOL/Induct/Common_Patterns.thy, see also
  2899 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  2900 examples.
  2901 
  2902 * Method "induct": improved handling of simultaneous goals. Instead of
  2903 introducing object-level conjunction, the statement is now split into
  2904 several conclusions, while the corresponding symbolic cases are nested
  2905 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  2906 see src/HOL/Induct/Common_Patterns.thy, for example.
  2907 
  2908 * Method "induct": mutual induction rules are now specified as a list
  2909 of rule sharing the same induction cases. HOL packages usually provide
  2910 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  2911 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  2912 mutual induction rules differently, i.e. like this:
  2913 
  2914   (induct rule: foo_bar.inducts)
  2915   (induct set: foo bar)
  2916   (induct pred: foo bar)
  2917   (induct type: foo bar)
  2918 
  2919 The ML function ProjectRule.projections turns old-style rules into the
  2920 new format.
  2921 
  2922 * Method "coinduct": dual of induction, see
  2923 src/HOL/Library/Coinductive_List.thy for various examples.
  2924 
  2925 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  2926 considered a legacy feature.
  2927 
  2928 * Attribute "symmetric" produces result with standardized schematic
  2929 variables (index 0).  Potential INCOMPATIBILITY.
  2930 
  2931 * Simplifier: by default the simplifier trace only shows top level
  2932 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  2933 default. Thus there is less danger of being flooded by the trace. The
  2934 trace indicates where parts have been suppressed.
  2935   
  2936 * Provers/classical: removed obsolete classical version of elim_format
  2937 attribute; classical elim/dest rules are now treated uniformly when
  2938 manipulating the claset.
  2939 
  2940 * Provers/classical: stricter checks to ensure that supplied intro,
  2941 dest and elim rules are well-formed; dest and elim rules must have at
  2942 least one premise.
  2943 
  2944 * Provers/classical: attributes dest/elim/intro take an optional
  2945 weight argument for the rule (just as the Pure versions).  Weights are
  2946 ignored by automated tools, but determine the search order of single
  2947 rule steps.
  2948 
  2949 * Syntax: input syntax now supports dummy variable binding "%_. b",
  2950 where the body does not mention the bound variable.  Note that dummy
  2951 patterns implicitly depend on their context of bounds, which makes
  2952 "{_. _}" match any set comprehension as expected.  Potential
  2953 INCOMPATIBILITY -- parse translations need to cope with syntactic
  2954 constant "_idtdummy" in the binding position.
  2955 
  2956 * Syntax: removed obsolete syntactic constant "_K" and its associated
  2957 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  2958 for example "A -> B" => "Pi A (%_. B)".
  2959 
  2960 * Pure: 'class_deps' command visualizes the subclass relation, using
  2961 the graph browser tool.
  2962 
  2963 * Pure: 'print_theory' now suppresses certain internal declarations by
  2964 default; use '!' option for full details.
  2965 
  2966 
  2967 *** HOL ***
  2968 
  2969 * Method "metis" proves goals by applying the Metis general-purpose
  2970 resolution prover (see also http://gilith.com/software/metis/).
  2971 Examples are in the directory MetisExamples.  WARNING: the
  2972 Isabelle/HOL-Metis integration does not yet work properly with
  2973 multi-threading.
  2974   
  2975 * Command 'sledgehammer' invokes external automatic theorem provers as
  2976 background processes.  It generates calls to the "metis" method if
  2977 successful. These can be pasted into the proof.  Users do not have to
  2978 wait for the automatic provers to return.  WARNING: does not really
  2979 work with multi-threading.
  2980 
  2981 * New "auto_quickcheck" feature tests outermost goal statements for
  2982 potential counter-examples.  Controlled by ML references
  2983 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  2984 5000 milliseconds).  Fails silently if statements is outside of
  2985 executable fragment, or any other codgenerator problem occurs.
  2986 
  2987 * New constant "undefined" with axiom "undefined x = undefined".
  2988 
  2989 * Added class "HOL.eq", allowing for code generation with polymorphic
  2990 equality.
  2991 
  2992 * Some renaming of class constants due to canonical name prefixing in
  2993 the new 'class' package:
  2994 
  2995     HOL.abs ~> HOL.abs_class.abs
  2996     HOL.divide ~> HOL.divide_class.divide
  2997     0 ~> HOL.zero_class.zero
  2998     1 ~> HOL.one_class.one
  2999     op + ~> HOL.plus_class.plus
  3000     op - ~> HOL.minus_class.minus
  3001     uminus ~> HOL.minus_class.uminus
  3002     op * ~> HOL.times_class.times
  3003     op < ~> HOL.ord_class.less
  3004     op <= > HOL.ord_class.less_eq
  3005     Nat.power ~> Power.power_class.power
  3006     Nat.size ~> Nat.size_class.size
  3007     Numeral.number_of ~> Numeral.number_class.number_of
  3008     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3009     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3010     Orderings.min ~> Orderings.ord_class.min
  3011     Orderings.max ~> Orderings.ord_class.max
  3012     Divides.op div ~> Divides.div_class.div
  3013     Divides.op mod ~> Divides.div_class.mod
  3014     Divides.op dvd ~> Divides.div_class.dvd
  3015 
  3016 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3017 
  3018 a) User-defined constants using any of the names "plus", "minus",
  3019 "times", "less" or "less_eq". The standard syntax translations for
  3020 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3021 names.
  3022 
  3023 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3024 INCOMPATIBILITY: use more specific names.
  3025 
  3026 c) Permutative equations (e.g. "a + b = b + a")
  3027 Since the change of names also changes the order of terms, permutative
  3028 rewrite rules may get applied in a different order. Experience shows
  3029 that this is rarely the case (only two adaptions in the whole Isabelle
  3030 distribution).  INCOMPATIBILITY: rewrite proofs
  3031 
  3032 d) ML code directly refering to constant names
  3033 This in general only affects hand-written proof tactics, simprocs and
  3034 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3035 Consider using @{const_name} antiquotation.
  3036 
  3037 * New class "default" with associated constant "default".
  3038 
  3039 * Function "sgn" is now overloaded and available on int, real, complex
  3040 (and other numeric types), using class "sgn".  Two possible defs of
  3041 sgn are given as equational assumptions in the classes sgn_if and
  3042 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3043 INCOMPATIBILITY.
  3044 
  3045 * Locale "partial_order" now unified with class "order" (cf. theory
  3046 Orderings), added parameter "less".  INCOMPATIBILITY.
  3047 
  3048 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3049 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3050 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3051 
  3052 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3053 changed order of proof goals in instance proofs.
  3054 
  3055 * The transitivity reasoner for partial and linear orders is set up
  3056 for classes "order" and "linorder".  Instances of the reasoner are available
  3057 in all contexts importing or interpreting the corresponding locales.
  3058 Method "order" invokes the reasoner separately; the reasoner
  3059 is also integrated with the Simplifier as a solver.  Diagnostic
  3060 command 'print_orders' shows the available instances of the reasoner
  3061 in the current context.
  3062 
  3063 * Localized monotonicity predicate in theory "Orderings"; integrated
  3064 lemmas max_of_mono and min_of_mono with this predicate.
  3065 INCOMPATIBILITY.
  3066 
  3067 * Formulation of theorem "dense" changed slightly due to integration
  3068 with new class dense_linear_order.
  3069 
  3070 * Uniform lattice theory development in HOL.
  3071 
  3072     constants "meet" and "join" now named "inf" and "sup"
  3073     constant "Meet" now named "Inf"
  3074 
  3075     classes "meet_semilorder" and "join_semilorder" now named
  3076       "lower_semilattice" and "upper_semilattice"
  3077     class "lorder" now named "lattice"
  3078     class "comp_lat" now named "complete_lattice"
  3079 
  3080     Instantiation of lattice classes allows explicit definitions
  3081     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3082 
  3083   INCOMPATIBILITY.  Theorem renames:
  3084 
  3085     meet_left_le            ~> inf_le1
  3086     meet_right_le           ~> inf_le2
  3087     join_left_le            ~> sup_ge1
  3088     join_right_le           ~> sup_ge2
  3089     meet_join_le            ~> inf_sup_ord
  3090     le_meetI                ~> le_infI
  3091     join_leI                ~> le_supI
  3092     le_meet                 ~> le_inf_iff
  3093     le_join                 ~> ge_sup_conv
  3094     meet_idempotent         ~> inf_idem
  3095     join_idempotent         ~> sup_idem
  3096     meet_comm               ~> inf_commute
  3097     join_comm               ~> sup_commute
  3098     meet_leI1               ~> le_infI1
  3099     meet_leI2               ~> le_infI2
  3100     le_joinI1               ~> le_supI1
  3101     le_joinI2               ~> le_supI2
  3102     meet_assoc              ~> inf_assoc
  3103     join_assoc              ~> sup_assoc
  3104     meet_left_comm          ~> inf_left_commute
  3105     meet_left_idempotent    ~> inf_left_idem
  3106     join_left_comm          ~> sup_left_commute
  3107     join_left_idempotent    ~> sup_left_idem
  3108     meet_aci                ~> inf_aci
  3109     join_aci                ~> sup_aci
  3110     le_def_meet             ~> le_iff_inf
  3111     le_def_join             ~> le_iff_sup
  3112     join_absorp2            ~> sup_absorb2
  3113     join_absorp1            ~> sup_absorb1
  3114     meet_absorp1            ~> inf_absorb1
  3115     meet_absorp2            ~> inf_absorb2
  3116     meet_join_absorp        ~> inf_sup_absorb
  3117     join_meet_absorp        ~> sup_inf_absorb
  3118     distrib_join_le         ~> distrib_sup_le
  3119     distrib_meet_le         ~> distrib_inf_le
  3120 
  3121     add_meet_distrib_left   ~> add_inf_distrib_left
  3122     add_join_distrib_left   ~> add_sup_distrib_left
  3123     is_join_neg_meet        ~> is_join_neg_inf
  3124     is_meet_neg_join        ~> is_meet_neg_sup
  3125     add_meet_distrib_right  ~> add_inf_distrib_right
  3126     add_join_distrib_right  ~> add_sup_distrib_right
  3127     add_meet_join_distribs  ~> add_sup_inf_distribs
  3128     join_eq_neg_meet        ~> sup_eq_neg_inf
  3129     meet_eq_neg_join        ~> inf_eq_neg_sup
  3130     add_eq_meet_join        ~> add_eq_inf_sup
  3131     meet_0_imp_0            ~> inf_0_imp_0
  3132     join_0_imp_0            ~> sup_0_imp_0
  3133     meet_0_eq_0             ~> inf_0_eq_0
  3134     join_0_eq_0             ~> sup_0_eq_0
  3135     neg_meet_eq_join        ~> neg_inf_eq_sup
  3136     neg_join_eq_meet        ~> neg_sup_eq_inf
  3137     join_eq_if              ~> sup_eq_if
  3138 
  3139     mono_meet               ~> mono_inf
  3140     mono_join               ~> mono_sup
  3141     meet_bool_eq            ~> inf_bool_eq
  3142     join_bool_eq            ~> sup_bool_eq
  3143     meet_fun_eq             ~> inf_fun_eq
  3144     join_fun_eq             ~> sup_fun_eq
  3145     meet_set_eq             ~> inf_set_eq
  3146     join_set_eq             ~> sup_set_eq
  3147     meet1_iff               ~> inf1_iff
  3148     meet2_iff               ~> inf2_iff
  3149     meet1I                  ~> inf1I
  3150     meet2I                  ~> inf2I
  3151     meet1D1                 ~> inf1D1
  3152     meet2D1                 ~> inf2D1
  3153     meet1D2                 ~> inf1D2
  3154     meet2D2                 ~> inf2D2
  3155     meet1E                  ~> inf1E
  3156     meet2E                  ~> inf2E
  3157     join1_iff               ~> sup1_iff
  3158     join2_iff               ~> sup2_iff
  3159     join1I1                 ~> sup1I1
  3160     join2I1                 ~> sup2I1
  3161     join1I1                 ~> sup1I1
  3162     join2I2                 ~> sup1I2
  3163     join1CI                 ~> sup1CI
  3164     join2CI                 ~> sup2CI
  3165     join1E                  ~> sup1E
  3166     join2E                  ~> sup2E
  3167 
  3168     is_meet_Meet            ~> is_meet_Inf
  3169     Meet_bool_def           ~> Inf_bool_def
  3170     Meet_fun_def            ~> Inf_fun_def
  3171     Meet_greatest           ~> Inf_greatest
  3172     Meet_lower              ~> Inf_lower
  3173     Meet_set_def            ~> Inf_set_def
  3174 
  3175     Sup_def                 ~> Sup_Inf
  3176     Sup_bool_eq             ~> Sup_bool_def
  3177     Sup_fun_eq              ~> Sup_fun_def
  3178     Sup_set_eq              ~> Sup_set_def
  3179 
  3180     listsp_meetI            ~> listsp_infI
  3181     listsp_meet_eq          ~> listsp_inf_eq
  3182 
  3183     meet_min                ~> inf_min
  3184     join_max                ~> sup_max
  3185 
  3186 * Added syntactic class "size"; overloaded constant "size" now has
  3187 type "'a::size ==> bool"
  3188 
  3189 * Internal reorganisation of `size' of datatypes: size theorems
  3190 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3191 simplification rules by default!); theorems "prod.size" now named
  3192 "*.size".
  3193 
  3194 * Class "div" now inherits from class "times" rather than "type".
  3195 INCOMPATIBILITY.
  3196 
  3197 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  3198 Linorder etc.  have disappeared; operations defined in terms of
  3199 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  3200 
  3201 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  3202 
  3203 * HOL-Word: New extensive library and type for generic, fixed size
  3204 machine words, with arithemtic, bit-wise, shifting and rotating
  3205 operations, reflection into int, nat, and bool lists, automation for
  3206 linear arithmetic (by automatic reflection into nat or int), including
  3207 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  3208 arithmetic type classes, supporting automatic simplification of
  3209 numerals on all operations.
  3210 
  3211 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  3212 
  3213 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  3214 
  3215 * Code generator library theories:
  3216   - Code_Integer represents HOL integers by big integer literals in target
  3217     languages.
  3218   - Code_Char represents HOL characters by character literals in target
  3219     languages.
  3220   - Code_Char_chr like Code_Char, but also offers treatment of character
  3221     codes; includes Code_Integer.
  3222   - Executable_Set allows to generate code for finite sets using lists.
  3223   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  3224     denominator).
  3225   - Executable_Real implements a subset of real numbers, namly those
  3226     representable by rational numbers.
  3227   - Efficient_Nat implements natural numbers by integers, which in general will
  3228     result in higher efficency; pattern matching with 0/Suc is eliminated;
  3229     includes Code_Integer.
  3230   - Code_Index provides an additional datatype index which is mapped to
  3231     target-language built-in integers.
  3232   - Code_Message provides an additional datatype message_string which is isomorphic to
  3233     strings; messages are mapped to target-language strings.
  3234 
  3235 * New package for inductive predicates
  3236 
  3237   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  3238 
  3239     inductive
  3240       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3241       for z_1 :: U_1 and ... and z_n :: U_m
  3242     where
  3243       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3244     | ...
  3245 
  3246   with full support for type-inference, rather than
  3247 
  3248     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3249 
  3250     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3251     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3252 
  3253     inductive "s z_1 ... z_m"
  3254     intros
  3255       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3256       ...
  3257 
  3258   For backward compatibility, there is a wrapper allowing inductive
  3259   sets to be defined with the new package via
  3260 
  3261     inductive_set
  3262       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3263       for z_1 :: U_1 and ... and z_n :: U_m
  3264     where
  3265       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3266     | ...
  3267 
  3268   or
  3269 
  3270     inductive_set
  3271       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3272       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3273       for z_1 :: U_1 and ... and z_n :: U_m
  3274     where
  3275       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3276     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3277     | ...
  3278 
  3279   if the additional syntax "p ..." is required.
  3280 
  3281   Numerous examples can be found in the subdirectories src/HOL/Auth,
  3282   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  3283 
  3284   INCOMPATIBILITIES:
  3285 
  3286   - Since declaration and definition of inductive sets or predicates
  3287     is no longer separated, abbreviations involving the newly
  3288     introduced sets or predicates must be specified together with the
  3289     introduction rules after the 'where' keyword (see above), rather
  3290     than before the actual inductive definition.
  3291 
  3292   - The variables in induction and elimination rules are now
  3293     quantified in the order of their occurrence in the introduction
  3294     rules, rather than in alphabetical order. Since this may break
  3295     some proofs, these proofs either have to be repaired, e.g. by
  3296     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  3297     statements of the form
  3298 
  3299       case (rule_i a_i_1 ... a_i_{k_i})
  3300 
  3301     or the old order of quantification has to be restored by explicitly adding
  3302     meta-level quantifiers in the introduction rules, i.e.
  3303 
  3304       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  3305 
  3306   - The format of the elimination rules is now
  3307 
  3308       p z_1 ... z_m x_1 ... x_n ==>
  3309         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3310         ==> ... ==> P
  3311 
  3312     for predicates and
  3313 
  3314       (x_1, ..., x_n) : s z_1 ... z_m ==>
  3315         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3316         ==> ... ==> P
  3317 
  3318     for sets rather than
  3319 
  3320       x : s z_1 ... z_m ==>
  3321         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  3322         ==> ... ==> P
  3323 
  3324     This may require terms in goals to be expanded to n-tuples
  3325     (e.g. using case_tac or simplification with the split_paired_all
  3326     rule) before the above elimination rule is applicable.
  3327 
  3328   - The elimination or case analysis rules for (mutually) inductive
  3329     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  3330     list of rules "p_1_..._p_k.elims" is no longer available.
  3331 
  3332 * New package "function"/"fun" for general recursive functions,
  3333 supporting mutual and nested recursion, definitions in local contexts,
  3334 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  3335 for small examples, and the separate tutorial on the function
  3336 package. The old recdef "package" is still available as before, but
  3337 users are encouraged to use the new package.
  3338 
  3339 * Method "lexicographic_order" automatically synthesizes termination
  3340 relations as lexicographic combinations of size measures. 
  3341 
  3342 * Case-expressions allow arbitrary constructor-patterns (including
  3343 "_") and take their order into account, like in functional
  3344 programming.  Internally, this is translated into nested
  3345 case-expressions; missing cases are added and mapped to the predefined
  3346 constant "undefined". In complicated cases printing may no longer show
  3347 the original input but the internal form. Lambda-abstractions allow
  3348 the same form of pattern matching: "% pat1 => e1 | ..." is an
  3349 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  3350 variable.
  3351 
  3352 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  3353 is an abbreviation for "of_nat :: nat => int". The simplification
  3354 rules for "of_nat" have been changed to work like "int" did
  3355 previously.  Potential INCOMPATIBILITY:
  3356   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  3357   - of_nat_diff and of_nat_mult are no longer default simp rules
  3358 
  3359 * Method "algebra" solves polynomial equations over (semi)rings using
  3360 Groebner bases. The (semi)ring structure is defined by locales and the
  3361 tool setup depends on that generic context. Installing the method for
  3362 a specific type involves instantiating the locale and possibly adding
  3363 declarations for computation on the coefficients.  The method is
  3364 already instantiated for natural numbers and for the axiomatic class
  3365 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  3366 CALCULEMUS 2007 for the general principles underlying this
  3367 architecture of context-aware proof-tools.
  3368 
  3369 * Method "ferrack" implements quantifier elimination over
  3370 special-purpose dense linear orders using locales (analogous to
  3371 "algebra"). The method is already installed for class
  3372 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  3373 rat, etc.
  3374 
  3375 * Former constant "List.op @" now named "List.append".  Use ML
  3376 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  3377 circumvent possible incompatibilities when working on ML level.
  3378 
  3379 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  3380 
  3381 * New function listsum :: 'a list => 'a for arbitrary monoids.
  3382 Special syntax: "SUM x <- xs. f x" (and latex variants)
  3383 
  3384 * New syntax for Haskell-like list comprehension (input only), eg.
  3385 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  3386 
  3387 * The special syntax for function "filter" has changed from [x :
  3388 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  3389 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  3390 
  3391 * [a..b] is now defined for arbitrary linear orders.  It used to be
  3392 defined on nat only, as an abbreviation for [a..<Suc b]
  3393 INCOMPATIBILITY.
  3394 
  3395 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  3396 
  3397 * New functions "sorted" and "sort" in src/HOL/List.thy.
  3398 
  3399 * New lemma collection field_simps (an extension of ring_simps) for
  3400 manipulating (in)equations involving division. Multiplies with all
  3401 denominators that can be proved to be non-zero (in equations) or
  3402 positive/negative (in inequations).
  3403 
  3404 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  3405 have been improved and renamed to ring_simps, group_simps and
  3406 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  3407 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  3408 
  3409 * Theory Library/Commutative_Ring: switched from recdef to function
  3410 package; constants add, mul, pow now curried.  Infix syntax for
  3411 algebraic operations.
  3412 
  3413 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  3414 INCOMPATIBILITY.
  3415 
  3416 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  3417 INCOMPATIBILITY.
  3418 
  3419 * HOL/records: generalised field-update to take a function on the
  3420 field rather than the new value: r(|A := x|) is translated to A_update
  3421 (K x) r The K-combinator that is internally used is called K_record.
  3422 INCOMPATIBILITY: Usage of the plain update functions has to be
  3423 adapted.
  3424  
  3425 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  3426 * x = 0, which are required for a semiring.  Richer structures do not
  3427 inherit from semiring_0 anymore, because this property is a theorem
  3428 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  3429 there is more to prove, but this is mostly trivial.
  3430 
  3431 * Class "recpower" is generalized to arbitrary monoids, not just
  3432 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  3433 commutativity or semiring properties additionally.
  3434 
  3435 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  3436 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  3437 better use 'abbreviation'.
  3438 
  3439 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  3440 
  3441 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  3442 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  3443 significant changes for setting up numeral syntax for types:
  3444   - New constants Numeral.pred and Numeral.succ instead
  3445       of former Numeral.bin_pred and Numeral.bin_succ.
  3446   - Use integer operations instead of bin_add, bin_mult and so on.
  3447   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  3448   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  3449 
  3450 See src/HOL/Integ/IntArith.thy for an example setup.
  3451 
  3452 * Command 'normal_form' computes the normal form of a term that may
  3453 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  3454 produces ``[b, c, a]'' (without proof).  This command is suitable for
  3455 heavy-duty computations because the functions are compiled to ML
  3456 first.  Correspondingly, a method "normalization" is provided.  See
  3457 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  3458 
  3459 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  3460 25 like -->); output depends on the "iff" print_mode, the default is
  3461 "A = B" (with priority 50).
  3462 
  3463 * Relations less (<) and less_eq (<=) are also available on type bool.
  3464 Modified syntax to disallow nesting without explicit parentheses,
  3465 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  3466 INCOMPATIBILITY.
  3467 
  3468 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  3469 
  3470 * Relation composition operator "op O" now has precedence 75 and binds
  3471 stronger than union and intersection. INCOMPATIBILITY.
  3472 
  3473 * The old set interval syntax "{m..n(}" (and relatives) has been
  3474 removed.  Use "{m..<n}" (and relatives) instead.
  3475 
  3476 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  3477 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  3478 ``declare [[simproc del: neq]]''.
  3479 
  3480 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  3481 True/False.
  3482 
  3483 * Theorem Cons_eq_map_conv no longer declared as "simp".
  3484 
  3485 * Theorem setsum_mult renamed to setsum_right_distrib.
  3486 
  3487 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  3488 ``rule'' method.
  3489 
  3490 * Reimplemented methods "sat" and "satx", with several improvements:
  3491 goals no longer need to be stated as "<prems> ==> False", equivalences
  3492 (i.e. "=" on type bool) are handled, variable names of the form
  3493 "lit_<n>" are no longer reserved, significant speedup.
  3494 
  3495 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  3496 zChaff is still supported as well.
  3497 
  3498 * 'inductive' and 'datatype': provide projections of mutual rules,
  3499 bundled as foo_bar.inducts;
  3500 
  3501 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  3502 Library.
  3503 
  3504 * Library: moved theory Accessible_Part to main HOL.
  3505 
  3506 * Library: added theory Coinductive_List of potentially infinite lists
  3507 as greatest fixed-point.
  3508 
  3509 * Library: added theory AssocList which implements (finite) maps as
  3510 association lists.
  3511 
  3512 * Method "evaluation" solves goals (i.e. a boolean expression)
  3513 efficiently by compiling it to ML.  The goal is "proved" (via an
  3514 oracle) if it evaluates to True.
  3515 
  3516 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  3517 also when invoked by the simplifier.  This results in the Simplifier
  3518 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  3519 Configuration option fast_arith_split_limit=0 recovers the old
  3520 behavior.
  3521 
  3522 * Support for hex (0x20) and binary (0b1001) numerals.
  3523 
  3524 * New method: reify eqs (t), where eqs are equations for an
  3525 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  3526 parameter, computes a term s::'b and a list xs::'a list and proves the
  3527 theorem I xs s = t. This is also known as reification or quoting. The
  3528 resulting theorem is applied to the subgoal to substitute t with I xs
  3529 s.  If t is omitted, the subgoal itself is reified.
  3530 
  3531 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  3532 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  3533 where f is supposed to be a computable function (in the sense of code
  3534 generattion). The method uses reify to compute s and xs as above then
  3535 applies corr_thm and uses normalization by evaluation to "prove" f s =
  3536 r and finally gets the theorem t = r, which is again applied to the
  3537 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  3538 
  3539 * Reflection: Automatic reification now handels binding, an example is
  3540 available in src/HOL/ex/ReflectionEx.thy
  3541 
  3542 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  3543 command 'statespace' that is similar to 'record', but introduces an
  3544 abstract specification based on the locale infrastructure instead of
  3545 HOL types.  This leads to extra flexibility in composing state spaces,
  3546 in particular multiple inheritance and renaming of components.
  3547 
  3548 
  3549 *** HOL-Complex ***
  3550 
  3551 * Hyperreal: Functions root and sqrt are now defined on negative real
  3552 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  3553 Nonnegativity side conditions have been removed from many lemmas, so
  3554 that more subgoals may now be solved by simplification; potential
  3555 INCOMPATIBILITY.
  3556 
  3557 * Real: new type classes formalize real normed vector spaces and
  3558 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  3559 and norm :: 'a => real.
  3560 
  3561 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  3562 reals into other types. The overloaded constant Reals :: 'a set is now
  3563 defined as range of_real; potential INCOMPATIBILITY.
  3564 
  3565 * Real: proper support for ML code generation, including 'quickcheck'.
  3566 Reals are implemented as arbitrary precision rationals.
  3567 
  3568 * Hyperreal: Several constants that previously worked only for the
  3569 reals have been generalized, so they now work over arbitrary vector
  3570 spaces. Type annotations may need to be added in some cases; potential
  3571 INCOMPATIBILITY.
  3572 
  3573   Infinitesimal  :: ('a::real_normed_vector) star set
  3574   HFinite        :: ('a::real_normed_vector) star set
  3575   HInfinite      :: ('a::real_normed_vector) star set
  3576   approx         :: ('a::real_normed_vector) star => 'a star => bool
  3577   monad          :: ('a::real_normed_vector) star => 'a star set
  3578   galaxy         :: ('a::real_normed_vector) star => 'a star set
  3579   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  3580   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  3581   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  3582   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  3583   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  3584   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  3585   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  3586   sgn            :: 'a::real_normed_vector => 'a
  3587   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  3588 
  3589 * Complex: Some complex-specific constants are now abbreviations for
  3590 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  3591 hnorm.  Other constants have been entirely removed in favor of the
  3592 polymorphic versions (INCOMPATIBILITY):
  3593 
  3594   approx        <-- capprox
  3595   HFinite       <-- CFinite
  3596   HInfinite     <-- CInfinite
  3597   Infinitesimal <-- CInfinitesimal
  3598   monad         <-- cmonad
  3599   galaxy        <-- cgalaxy
  3600   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  3601   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  3602   (ns)deriv     <-- (ns)cderiv
  3603 
  3604 
  3605 *** HOL-Algebra ***
  3606 
  3607 * Formalisation of ideals and the quotient construction over rings.
  3608 
  3609 * Order and lattice theory no longer based on records.
  3610 INCOMPATIBILITY.
  3611 
  3612 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  3613 greatest_closed.  INCOMPATIBILITY.
  3614 
  3615 * Method algebra is now set up via an attribute.  For examples see
  3616 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  3617 of algebraic structures.
  3618 
  3619 * Renamed theory CRing to Ring.
  3620 
  3621 
  3622 *** HOL-Nominal ***
  3623 
  3624 * Substantial, yet incomplete support for nominal datatypes (binding
  3625 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  3626 src/HOL/Nominal/Examples.  Prospective users should consult
  3627 http://isabelle.in.tum.de/nominal/
  3628 
  3629 
  3630 *** ML ***
  3631 
  3632 * ML basics: just one true type int, which coincides with IntInf.int
  3633 (even on SML/NJ).
  3634 
  3635 * ML within Isar: antiquotations allow to embed statically-checked
  3636 formal entities in the source, referring to the context available at
  3637 compile-time.  For example:
  3638 
  3639 ML {* @{sort "{zero,one}"} *}
  3640 ML {* @{typ "'a => 'b"} *}
  3641 ML {* @{term "%x. x"} *}
  3642 ML {* @{prop "x == y"} *}
  3643 ML {* @{ctyp "'a => 'b"} *}
  3644 ML {* @{cterm "%x. x"} *}
  3645 ML {* @{cprop "x == y"} *}
  3646 ML {* @{thm asm_rl} *}
  3647 ML {* @{thms asm_rl} *}
  3648 ML {* @{type_name c} *}
  3649 ML {* @{type_syntax c} *}
  3650 ML {* @{const_name c} *}
  3651 ML {* @{const_syntax c} *}
  3652 ML {* @{context} *}
  3653 ML {* @{theory} *}
  3654 ML {* @{theory Pure} *}
  3655 ML {* @{theory_ref} *}
  3656 ML {* @{theory_ref Pure} *}
  3657 ML {* @{simpset} *}
  3658 ML {* @{claset} *}
  3659 ML {* @{clasimpset} *}
  3660 
  3661 The same works for sources being ``used'' within an Isar context.
  3662 
  3663 * ML in Isar: improved error reporting; extra verbosity with
  3664 ML_Context.trace enabled.
  3665 
  3666 * Pure/General/table.ML: the join operations now works via exceptions
  3667 DUP/SAME instead of type option. This is simpler in simple cases, and
  3668 admits slightly more efficient complex applications.
  3669 
  3670 * Pure: 'advanced' translation functions (parse_translation etc.) now
  3671 use Context.generic instead of just theory.
  3672 
  3673 * Pure: datatype Context.generic joins theory/Proof.context and
  3674 provides some facilities for code that works in either kind of
  3675 context, notably GenericDataFun for uniform theory and proof data.
  3676 
  3677 * Pure: simplified internal attribute type, which is now always
  3678 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  3679 local (Proof.context) attributes have been discontinued, while
  3680 minimizing code duplication. Thm.rule_attribute and
  3681 Thm.declaration_attribute build canonical attributes; see also structure
  3682 Context for further operations on Context.generic, notably
  3683 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  3684 declarations and definitions.
  3685 
  3686 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  3687 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  3688 init only required for impure data. INCOMPATIBILITY: empty really need
  3689 to be empty (no dependencies on theory content!)
  3690 
  3691 * Pure/kernel: consts certification ignores sort constraints given in
  3692 signature declarations. (This information is not relevant to the
  3693 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  3694 potential INCOMPATIBILITY.
  3695 
  3696 * Pure: axiomatic type classes are now purely definitional, with
  3697 explicit proofs of class axioms and super class relations performed
  3698 internally. See Pure/axclass.ML for the main internal interfaces --
  3699 notably AxClass.define_class supercedes AxClass.add_axclass, and
  3700 AxClass.axiomatize_class/classrel/arity supersede
  3701 Sign.add_classes/classrel/arities.
  3702 
  3703 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  3704 global/local versions on theory vs. Proof.context have been
  3705 discontinued; Attrib.syntax and Method.syntax have been adapted
  3706 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  3707 attributes, methods, etc.
  3708 
  3709 * Pure: several functions of signature "... -> theory -> theory * ..."
  3710 have been reoriented to "... -> theory -> ... * theory" in order to
  3711 allow natural usage in combination with the ||>, ||>>, |-> and
  3712 fold_map combinators.
  3713 
  3714 * Pure: official theorem names (closed derivations) and additional
  3715 comments (tags) are now strictly separate.  Name hints -- which are
  3716 maintained as tags -- may be attached any time without affecting the
  3717 derivation.
  3718 
  3719 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  3720 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  3721 achieve the old behaviour.
  3722 
  3723 * Pure: the "Goal" constant is now called "prop", supporting a
  3724 slightly more general idea of ``protecting'' meta-level rule
  3725 statements.
  3726 
  3727 * Pure: Logic.(un)varify only works in a global context, which is now
  3728 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  3729 Logic.legacy_(un)varify as temporary workaround.
  3730 
  3731 * Pure: structure Name provides scalable operations for generating
  3732 internal variable names, notably Name.variants etc.  This replaces
  3733 some popular functions from term.ML:
  3734 
  3735   Term.variant		->  Name.variant
  3736   Term.variantlist	->  Name.variant_list
  3737   Term.invent_names	->  Name.invent_list
  3738 
  3739 Note that low-level renaming rarely occurs in new code -- operations
  3740 from structure Variable are used instead (see below).
  3741 
  3742 * Pure: structure Variable provides fundamental operations for proper
  3743 treatment of fixed/schematic variables in a context.  For example,
  3744 Variable.import introduces fixes for schematics of given facts and
  3745 Variable.export reverses the effect (up to renaming) -- this replaces
  3746 various freeze_thaw operations.
  3747 
  3748 * Pure: structure Goal provides simple interfaces for
  3749 init/conclude/finish and tactical prove operations (replacing former
  3750 Tactic.prove).  Goal.prove is the canonical way to prove results
  3751 within a given context; Goal.prove_global is a degraded version for
  3752 theory level goals, including a global Drule.standard.  Note that
  3753 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  3754 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  3755 in a locale context).
  3756 
  3757 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  3758 and type checking (Syntax.check_term etc.), with common combinations
  3759 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  3760 which are considered legacy and await removal.
  3761 
  3762 * Pure/Syntax: generic interfaces for type unchecking
  3763 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  3764 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  3765 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  3766 available for convenience, but refer to the very same operations using
  3767 a mere theory instead of a full context.
  3768 
  3769 * Isar: simplified treatment of user-level errors, using exception
  3770 ERROR of string uniformly.  Function error now merely raises ERROR,
  3771 without any side effect on output channels.  The Isar toplevel takes
  3772 care of proper display of ERROR exceptions.  ML code may use plain
  3773 handle/can/try; cat_error may be used to concatenate errors like this:
  3774 
  3775   ... handle ERROR msg => cat_error msg "..."
  3776 
  3777 Toplevel ML code (run directly or through the Isar toplevel) may be
  3778 embedded into the Isar toplevel with exception display/debug like
  3779 this:
  3780 
  3781   Isar.toplevel (fn () => ...)
  3782 
  3783 INCOMPATIBILITY, removed special transform_error facilities, removed
  3784 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  3785 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  3786 -- use plain ERROR instead.
  3787 
  3788 * Isar: theory setup now has type (theory -> theory), instead of a
  3789 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  3790 
  3791 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  3792 ProofContext.debug/verbose flags.
  3793 
  3794 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  3795 theory before entering a proof state.  Transactions now always see a
  3796 quasi-functional intermediate checkpoint, both in interactive and
  3797 batch mode.
  3798 
  3799 * Isar: simplified interfaces for outer syntax.  Renamed
  3800 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  3801 OuterSyntax.add_parsers -- this functionality is now included in
  3802 OuterSyntax.command etc.  INCOMPATIBILITY.
  3803 
  3804 * Simplifier: the simpset of a running simplification process now
  3805 contains a proof context (cf. Simplifier.the_context), which is the
  3806 very context that the initial simpset has been retrieved from (by
  3807 simpset_of/local_simpset_of).  Consequently, all plug-in components
  3808 (solver, looper etc.) may depend on arbitrary proof data.
  3809 
  3810 * Simplifier.inherit_context inherits the proof context (plus the
  3811 local bounds) of the current simplification process; any simproc
  3812 etc. that calls the Simplifier recursively should do this!  Removed
  3813 former Simplifier.inherit_bounds, which is already included here --
  3814 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  3815 specify an explicit context using Simplifier.context/theory_context.
  3816 
  3817 * Simplifier/Classical Reasoner: more abstract interfaces
  3818 change_simpset/claset for modifying the simpset/claset reference of a
  3819 theory; raw versions simpset/claset_ref etc. have been discontinued --
  3820 INCOMPATIBILITY.
  3821 
  3822 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  3823 "Trueprop" etc.
  3824 
  3825 
  3826 *** System ***
  3827 
  3828 * settings: the default heap location within ISABELLE_HOME_USER now
  3829 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  3830 Isabelle installations.
  3831 
  3832 * isabelle-process: option -S (secure mode) disables some critical
  3833 operations, notably runtime compilation and evaluation of ML source
  3834 code.
  3835 
  3836 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  3837 
  3838 * Support for parallel execution, using native multicore support of
  3839 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  3840 independent theories, according to the given theory header
  3841 specifications. The maximum number of worker threads is specified via
  3842 usedir option -M or the "max-threads" setting in Proof General. A
  3843 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  3844 to 6 on a 8-core machine.  User-code needs to observe certain
  3845 guidelines for thread-safe programming, see appendix A in the Isar
  3846 Implementation manual.
  3847 
  3848 
  3849 
  3850 New in Isabelle2005 (October 2005)
  3851 ----------------------------------
  3852 
  3853 *** General ***
  3854 
  3855 * Theory headers: the new header syntax for Isar theories is
  3856 
  3857   theory <name>
  3858   imports <theory1> ... <theoryN>
  3859   uses <file1> ... <fileM>
  3860   begin
  3861 
  3862 where the 'uses' part is optional.  The previous syntax
  3863 
  3864   theory <name> = <theory1> + ... + <theoryN>:
  3865 
  3866 will disappear in the next release.  Use isatool fixheaders to convert
  3867 existing theory files.  Note that there is no change in ancient
  3868 non-Isar theories now, but these will disappear soon.
  3869 
  3870 * Theory loader: parent theories can now also be referred to via
  3871 relative and absolute paths.
  3872 
  3873 * Command 'find_theorems' searches for a list of criteria instead of a
  3874 list of constants. Known criteria are: intro, elim, dest, name:string,
  3875 simp:term, and any term. Criteria can be preceded by '-' to select
  3876 theorems that do not match. Intro, elim, dest select theorems that
  3877 match the current goal, name:s selects theorems whose fully qualified
  3878 name contain s, and simp:term selects all simplification rules whose
  3879 lhs match term.  Any other term is interpreted as pattern and selects
  3880 all theorems matching the pattern. Available in ProofGeneral under
  3881 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  3882 
  3883   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  3884 
  3885 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  3886 matching the current goal as introduction rule and not having "HOL."
  3887 in their name (i.e. not being defined in theory HOL).
  3888 
  3889 * Command 'thms_containing' has been discontinued in favour of
  3890 'find_theorems'; INCOMPATIBILITY.
  3891 
  3892 * Communication with Proof General is now 8bit clean, which means that
  3893 Unicode text in UTF-8 encoding may be used within theory texts (both
  3894 formal and informal parts).  Cf. option -U of the Isabelle Proof
  3895 General interface.  Here are some simple examples (cf. src/HOL/ex):
  3896 
  3897   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  3898   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  3899 
  3900 * Improved efficiency of the Simplifier and, to a lesser degree, the
  3901 Classical Reasoner.  Typical big applications run around 2 times
  3902 faster.
  3903 
  3904 
  3905 *** Document preparation ***
  3906 
  3907 * Commands 'display_drafts' and 'print_drafts' perform simple output
  3908 of raw sources.  Only those symbols that do not require additional
  3909 LaTeX packages (depending on comments in isabellesym.sty) are
  3910 displayed properly, everything else is left verbatim.  isatool display
  3911 and isatool print are used as front ends (these are subject to the
  3912 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  3913 
  3914 * Command tags control specific markup of certain regions of text,
  3915 notably folding and hiding.  Predefined tags include "theory" (for
  3916 theory begin and end), "proof" for proof commands, and "ML" for
  3917 commands involving ML code; the additional tags "visible" and
  3918 "invisible" are unused by default.  Users may give explicit tag
  3919 specifications in the text, e.g. ''by %invisible (auto)''.  The
  3920 interpretation of tags is determined by the LaTeX job during document
  3921 preparation: see option -V of isatool usedir, or options -n and -t of
  3922 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  3923 \isadroptag.
  3924 
  3925 Several document versions may be produced at the same time via isatool
  3926 usedir (the generated index.html will link all of them).  Typical
  3927 specifications include ''-V document=theory,proof,ML'' to present
  3928 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  3929 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  3930 these parts without any formal replacement text.  The Isabelle site
  3931 default settings produce ''document'' and ''outline'' versions as
  3932 specified above.
  3933 
  3934 * Several new antiquotations:
  3935 
  3936   @{term_type term} prints a term with its type annotated;
  3937 
  3938   @{typeof term} prints the type of a term;
  3939 
  3940   @{const const} is the same as @{term const}, but checks that the
  3941   argument is a known logical constant;
  3942 
  3943   @{term_style style term} and @{thm_style style thm} print a term or
  3944   theorem applying a "style" to it
  3945 
  3946   @{ML text}
  3947 
  3948 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  3949 definitions, equations, inequations etc., 'concl' printing only the
  3950 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  3951 to print the specified premise.  TermStyle.add_style provides an ML
  3952 interface for introducing further styles.  See also the "LaTeX Sugar"
  3953 document practical applications.  The ML antiquotation prints
  3954 type-checked ML expressions verbatim.
  3955 
  3956 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  3957 and 'text' support optional locale specification '(in loc)', which
  3958 specifies the default context for interpreting antiquotations.  For
  3959 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  3960 
  3961 * Option 'locale=NAME' of antiquotations specifies an alternative
  3962 context interpreting the subsequent argument.  For example: @{thm
  3963 [locale=lattice] inf_assoc}.
  3964 
  3965 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  3966 a proof context.
  3967 
  3968 * Proper output of antiquotations for theory commands involving a
  3969 proof context (such as 'locale' or 'theorem (in loc) ...').
  3970 
  3971 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  3972 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  3973 
  3974 * isatool usedir: new option -C (default true) controls whether option
  3975 -D should include a copy of the original document directory; -C false
  3976 prevents unwanted effects such as copying of administrative CVS data.
  3977 
  3978 
  3979 *** Pure ***
  3980 
  3981 * Considerably improved version of 'constdefs' command.  Now performs
  3982 automatic type-inference of declared constants; additional support for
  3983 local structure declarations (cf. locales and HOL records), see also
  3984 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  3985 sequential dependencies of definitions within a single 'constdefs'
  3986 section; moreover, the declared name needs to be an identifier.  If
  3987 all fails, consider to fall back on 'consts' and 'defs' separately.
  3988 
  3989 * Improved indexed syntax and implicit structures.  First of all,
  3990 indexed syntax provides a notational device for subscripted
  3991 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  3992 expressions.  Secondly, in a local context with structure
  3993 declarations, number indexes \<^sub>n or the empty index (default
  3994 number 1) refer to a certain fixed variable implicitly; option
  3995 show_structs controls printing of implicit structures.  Typical
  3996 applications of these concepts involve record types and locales.
  3997 
  3998 * New command 'no_syntax' removes grammar declarations (and
  3999 translations) resulting from the given syntax specification, which is
  4000 interpreted in the same manner as for the 'syntax' command.
  4001 
  4002 * 'Advanced' translation functions (parse_translation etc.) may depend
  4003 on the signature of the theory context being presently used for
  4004 parsing/printing, see also isar-ref manual.
  4005 
  4006 * Improved 'oracle' command provides a type-safe interface to turn an
  4007 ML expression of type theory -> T -> term into a primitive rule of
  4008 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4009 is already included here); see also FOL/ex/IffExample.thy;
  4010 INCOMPATIBILITY.
  4011 
  4012 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4013 before); "cI" is no longer bound, use "c.intro" instead.
  4014 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4015 axclasses vs. locales.
  4016 
  4017 * Improved internal renaming of symbolic identifiers -- attach primes
  4018 instead of base 26 numbers.
  4019 
  4020 * New flag show_question_marks controls printing of leading question
  4021 marks in schematic variable names.
  4022 
  4023 * In schematic variable names, *any* symbol following \<^isub> or
  4024 \<^isup> is now treated as part of the base name.  For example, the
  4025 following works without printing of awkward ".0" indexes:
  4026 
  4027   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4028     by simp
  4029 
  4030 * Inner syntax includes (*(*nested*) comments*).
  4031 
  4032 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4033 annotations as "(00...)".
  4034 
  4035 * Clear separation of logical types and nonterminals, where the latter
  4036 may only occur in 'syntax' specifications or type abbreviations.
  4037 Before that distinction was only partially implemented via type class
  4038 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4039 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4040 exotic syntax specifications may require further adaption
  4041 (e.g. Cube/Cube.thy).
  4042 
  4043 * Removed obsolete type class "logic", use the top sort {} instead.
  4044 Note that non-logical types should be declared as 'nonterminals'
  4045 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4046 specifications.
  4047 
  4048 * Attributes 'induct' and 'cases': type or set names may now be
  4049 locally fixed variables as well.
  4050 
  4051 * Simplifier: can now control the depth to which conditional rewriting
  4052 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4053 Limit.
  4054 
  4055 * Simplifier: simplification procedures may now take the current
  4056 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4057 interface), which is very useful for calling the Simplifier
  4058 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4059 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4060 low-level mk_simproc no longer applies Logic.varify internally, to
  4061 allow for use in a context of fixed variables.
  4062 
  4063 * thin_tac now works even if the assumption being deleted contains !!
  4064 or ==>.  More generally, erule now works even if the major premise of
  4065 the elimination rule contains !! or ==>.
  4066 
  4067 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4068 
  4069 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4070 from Pure, which contains all common declarations already.  Both
  4071 theories are defined via plain Isabelle/Isar .thy files.
  4072 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4073 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4074 use isatool fixcpure to adapt your theory and ML sources.
  4075 
  4076 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4077 selections of theorems in named facts via index ranges.
  4078 
  4079 * 'print_theorems': in theory mode, really print the difference
  4080 wrt. the last state (works for interactive theory development only),
  4081 in proof mode print all local facts (cf. 'print_facts');
  4082 
  4083 * 'hide': option '(open)' hides only base names.
  4084 
  4085 * More efficient treatment of intermediate checkpoints in interactive
  4086 theory development.
  4087 
  4088 * Code generator is now invoked via code_module (incremental code
  4089 generation) and code_library (modular code generation, ML structures
  4090 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4091 must be quoted when used as identifiers.
  4092 
  4093 * New 'value' command for reading, evaluating and printing terms using
  4094 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4095 quoted when used as identifier.
  4096 
  4097 
  4098 *** Locales ***
  4099 
  4100 * New commands for the interpretation of locale expressions in
  4101 theories (1), locales (2) and proof contexts (3).  These generate
  4102 proof obligations from the expression specification.  After the
  4103 obligations have been discharged, theorems of the expression are added
  4104 to the theory, target locale or proof context.  The synopsis of the
  4105 commands is a follows:
  4106 
  4107   (1) interpretation expr inst
  4108   (2) interpretation target < expr
  4109   (3) interpret expr inst
  4110 
  4111 Interpretation in theories and proof contexts require a parameter
  4112 instantiation of terms from the current context.  This is applied to
  4113 specifications and theorems of the interpreted expression.
  4114 Interpretation in locales only permits parameter renaming through the
  4115 locale expression.  Interpretation is smart in that interpretations
  4116 that are active already do not occur in proof obligations, neither are
  4117 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4118 inspect active interpretations of a particular locale.  For details,
  4119 see the Isar Reference manual.  Examples can be found in
  4120 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4121 
  4122 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4123 'interpret' instead.
  4124 
  4125 * New context element 'constrains' for adding type constraints to
  4126 parameters.
  4127 
  4128 * Context expressions: renaming of parameters with syntax
  4129 redeclaration.
  4130 
  4131 * Locale declaration: 'includes' disallowed.
  4132 
  4133 * Proper static binding of attribute syntax -- i.e. types / terms /
  4134 facts mentioned as arguments are always those of the locale definition
  4135 context, independently of the context of later invocations.  Moreover,
  4136 locale operations (renaming and type / term instantiation) are applied
  4137 to attribute arguments as expected.
  4138 
  4139 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4140 actual attributes; rare situations may require Attrib.attribute to
  4141 embed those attributes into Attrib.src that lack concrete syntax.
  4142 Attribute implementations need to cooperate properly with the static
  4143 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4144 Attrib.XXX_thm etc. already do the right thing without further
  4145 intervention.  Only unusual applications -- such as "where" or "of"
  4146 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4147 on the context and the facts involved -- may have to assign parsed
  4148 values to argument tokens explicitly.
  4149 
  4150 * Changed parameter management in theorem generation for long goal
  4151 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4152 theorem statement in rare situations.
  4153 
  4154 * Locale inspection command 'print_locale' omits notes elements.  Use
  4155 'print_locale!' to have them included in the output.
  4156 
  4157 
  4158 *** Provers ***
  4159 
  4160 * Provers/hypsubst.ML: improved version of the subst method, for
  4161 single-step rewriting: it now works in bound variable contexts. New is
  4162 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4163 rewrite a different subterm than the original subst method, which is
  4164 still available as 'simplesubst'.
  4165 
  4166 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4167 and quasi orders.
  4168 
  4169 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4170 reflexive-transitive closure of relations.
  4171 
  4172 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4173 limit (previously hard-coded with a value of 20) user-definable.
  4174 
  4175 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4176 is peformed already.  Object-logics merely need to finish their
  4177 initial simpset configuration as before.  INCOMPATIBILITY.
  4178 
  4179 
  4180 *** HOL ***
  4181 
  4182 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4183 
  4184   syntax (epsilon)
  4185     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4186 
  4187 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4188 and x-symbol; use option '-m epsilon' to get it actually printed.
  4189 Moreover, the mathematically important symbolic identifier \<epsilon>
  4190 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4191 
  4192 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  4193 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  4194 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  4195 support corresponding Isar calculations.
  4196 
  4197 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  4198 instead of ":".
  4199 
  4200 * theory SetInterval: changed the syntax for open intervals:
  4201 
  4202   Old       New
  4203   {..n(}    {..<n}
  4204   {)n..}    {n<..}
  4205   {m..n(}   {m..<n}
  4206   {)m..n}   {m<..n}
  4207   {)m..n(}  {m<..<n}
  4208 
  4209 The old syntax is still supported but will disappear in the next
  4210 release.  For conversion use the following Emacs search and replace
  4211 patterns (these are not perfect but work quite well):
  4212 
  4213   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  4214   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  4215 
  4216 * Theory Commutative_Ring (in Library): method comm_ring for proving
  4217 equalities in commutative rings; method 'algebra' provides a generic
  4218 interface.
  4219 
  4220 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  4221 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  4222 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  4223 be a tuple pattern.
  4224 
  4225 Some new syntax forms are available:
  4226 
  4227   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  4228   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  4229   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  4230   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  4231 
  4232 The latter form "\<Sum>x < k. e" used to be based on a separate
  4233 function "Summation", which has been discontinued.
  4234 
  4235 * theory Finite_Set: in structured induction proofs, the insert case
  4236 is now 'case (insert x F)' instead of the old counterintuitive 'case
  4237 (insert F x)'.
  4238 
  4239 * The 'refute' command has been extended to support a much larger
  4240 fragment of HOL, including axiomatic type classes, constdefs and
  4241 typedefs, inductive datatypes and recursion.
  4242 
  4243 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  4244 Requires zChaff with proof generation to be installed.  See
  4245 HOL/ex/SAT_Examples.thy for examples.
  4246 
  4247 * Datatype induction via method 'induct' now preserves the name of the
  4248 induction variable. For example, when proving P(xs::'a list) by
  4249 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  4250 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  4251 in unstructured proof scripts.
  4252 
  4253 * Reworked implementation of records.  Improved scalability for
  4254 records with many fields, avoiding performance problems for type
  4255 inference. Records are no longer composed of nested field types, but
  4256 of nested extension types. Therefore the record type only grows linear
  4257 in the number of extensions and not in the number of fields.  The
  4258 top-level (users) view on records is preserved.  Potential
  4259 INCOMPATIBILITY only in strange cases, where the theory depends on the
  4260 old record representation. The type generated for a record is called
  4261 <record_name>_ext_type.
  4262 
  4263 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  4264 proofs triggered by a record definition or a simproc (if
  4265 quick_and_dirty is enabled).  Definitions of large records can take
  4266 quite long.
  4267 
  4268 New simproc record_upd_simproc for simplification of multiple record
  4269 updates enabled by default.  Moreover, trivial updates are also
  4270 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  4271 occasionally, since simplification is more powerful by default.
  4272 
  4273 * typedef: proper support for polymorphic sets, which contain extra
  4274 type-variables in the term.
  4275 
  4276 * Simplifier: automatically reasons about transitivity chains
  4277 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  4278 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  4279 old proofs break occasionally as simplification may now solve more
  4280 goals than previously.
  4281 
  4282 * Simplifier: converts x <= y into x = y if assumption y <= x is
  4283 present.  Works for all partial orders (class "order"), in particular
  4284 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  4285 just like y <= x.
  4286 
  4287 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  4288 bound variable or a constant then the let is unfolded.  Otherwise
  4289 first a is simplified to b, and then f b is simplified to g. If
  4290 possible we abstract b from g arriving at "let x = b in h x",
  4291 otherwise we unfold the let and arrive at g.  The simproc can be
  4292 enabled/disabled by the reference use_let_simproc.  Potential
  4293 INCOMPATIBILITY since simplification is more powerful by default.
  4294 
  4295 * Classical reasoning: the meson method now accepts theorems as arguments.
  4296 
  4297 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  4298 jobs to provide advice on the provability of subgoals.
  4299 
  4300 * Theory OrderedGroup and Ring_and_Field: various additions and
  4301 improvements to faciliate calculations involving equalities and
  4302 inequalities.
  4303 
  4304 The following theorems have been eliminated or modified
  4305 (INCOMPATIBILITY):
  4306 
  4307   abs_eq             now named abs_of_nonneg
  4308   abs_of_ge_0        now named abs_of_nonneg
  4309   abs_minus_eq       now named abs_of_nonpos
  4310   imp_abs_id         now named abs_of_nonneg
  4311   imp_abs_neg_id     now named abs_of_nonpos
  4312   mult_pos           now named mult_pos_pos
  4313   mult_pos_le        now named mult_nonneg_nonneg
  4314   mult_pos_neg_le    now named mult_nonneg_nonpos
  4315   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  4316   mult_neg           now named mult_neg_neg
  4317   mult_neg_le        now named mult_nonpos_nonpos
  4318 
  4319 * The following lemmas in Ring_and_Field have been added to the simplifier:
  4320      
  4321      zero_le_square
  4322      not_square_less_zero 
  4323 
  4324   The following lemmas have been deleted from Real/RealPow:
  4325   
  4326      realpow_zero_zero
  4327      realpow_two
  4328      realpow_less
  4329      zero_le_power
  4330      realpow_two_le
  4331      abs_realpow_two
  4332      realpow_two_abs     
  4333 
  4334 * Theory Parity: added rules for simplifying exponents.
  4335 
  4336 * Theory List:
  4337 
  4338 The following theorems have been eliminated or modified
  4339 (INCOMPATIBILITY):
  4340 
  4341   list_all_Nil       now named list_all.simps(1)
  4342   list_all_Cons      now named list_all.simps(2)
  4343   list_all_conv      now named list_all_iff
  4344   set_mem_eq         now named mem_iff
  4345 
  4346 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  4347 asymptotic "big O" calculations.  See the notes in BigO.thy.
  4348 
  4349 
  4350 *** HOL-Complex ***
  4351 
  4352 * Theory RealDef: better support for embedding natural numbers and
  4353 integers in the reals.
  4354 
  4355 The following theorems have been eliminated or modified
  4356 (INCOMPATIBILITY):
  4357 
  4358   exp_ge_add_one_self  now requires no hypotheses
  4359   real_of_int_add      reversed direction of equality (use [symmetric])
  4360   real_of_int_minus    reversed direction of equality (use [symmetric])
  4361   real_of_int_diff     reversed direction of equality (use [symmetric])
  4362   real_of_int_mult     reversed direction of equality (use [symmetric])
  4363 
  4364 * Theory RComplete: expanded support for floor and ceiling functions.
  4365 
  4366 * Theory Ln is new, with properties of the natural logarithm
  4367 
  4368 * Hyperreal: There is a new type constructor "star" for making
  4369 nonstandard types.  The old type names are now type synonyms:
  4370 
  4371   hypreal = real star
  4372   hypnat = nat star
  4373   hcomplex = complex star
  4374 
  4375 * Hyperreal: Many groups of similarly-defined constants have been
  4376 replaced by polymorphic versions (INCOMPATIBILITY):
  4377 
  4378   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  4379 
  4380   starset      <-- starsetNat, starsetC
  4381   *s*          <-- *sNat*, *sc*
  4382   starset_n    <-- starsetNat_n, starsetC_n
  4383   *sn*         <-- *sNatn*, *scn*
  4384   InternalSets <-- InternalNatSets, InternalCSets
  4385 
  4386   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  4387   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  4388   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  4389   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  4390   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  4391 
  4392 * Hyperreal: Many type-specific theorems have been removed in favor of
  4393 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  4394 
  4395   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  4396   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  4397   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  4398   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  4399   right_minus <-- hypreal_add_minus
  4400   left_minus <-- {hypreal,hcomplex}_add_minus_left
  4401   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  4402   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  4403   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  4404   mult_1_right <-- hcomplex_mult_one_right
  4405   mult_zero_left <-- hcomplex_mult_zero_left
  4406   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  4407   right_distrib <-- hypnat_add_mult_distrib2
  4408   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  4409   right_inverse <-- hypreal_mult_inverse
  4410   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  4411   order_refl <-- {hypreal,hypnat}_le_refl
  4412   order_trans <-- {hypreal,hypnat}_le_trans
  4413   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  4414   order_less_le <-- {hypreal,hypnat}_less_le
  4415   linorder_linear <-- {hypreal,hypnat}_le_linear
  4416   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  4417   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  4418   add_nonneg_nonneg <-- hypreal_le_add_order
  4419 
  4420 * Hyperreal: Separate theorems having to do with type-specific
  4421 versions of constants have been merged into theorems that apply to the
  4422 new polymorphic constants (INCOMPATIBILITY):
  4423 
  4424   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  4425   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  4426   STAR_Un <-- {STAR,NatStar,STARC}_Un
  4427   STAR_Int <-- {STAR,NatStar,STARC}_Int
  4428   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  4429   STAR_subset <-- {STAR,NatStar,STARC}_subset
  4430   STAR_mem <-- {STAR,NatStar,STARC}_mem
  4431   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  4432   STAR_diff <-- {STAR,STARC}_diff
  4433   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  4434     STARC_hcomplex_of_complex}_image_subset
  4435   starset_n_Un <-- starset{Nat,C}_n_Un
  4436   starset_n_Int <-- starset{Nat,C}_n_Int
  4437   starset_n_Compl <-- starset{Nat,C}_n_Compl
  4438   starset_n_diff <-- starset{Nat,C}_n_diff
  4439   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  4440   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  4441   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  4442   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  4443   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  4444   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  4445   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  4446   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  4447   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  4448   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  4449   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  4450   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  4451   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  4452   starfun_diff <-- starfun{C,RC,CR}_diff
  4453   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  4454   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  4455   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  4456   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  4457   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  4458   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  4459   starfun_Id <-- starfunC_Id
  4460   starfun_approx <-- starfun{Nat,CR}_approx
  4461   starfun_capprox <-- starfun{C,RC}_capprox
  4462   starfun_abs <-- starfunNat_rabs
  4463   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  4464   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  4465   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  4466   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  4467   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  4468   starfun_add_approx <-- starfunCR_add_approx
  4469   starfun_inverse_inverse <-- starfunC_inverse_inverse
  4470   starfun_divide <-- starfun{C,CR,RC}_divide
  4471   starfun_n <-- starfun{Nat,C}_n
  4472   starfun_n_mult <-- starfun{Nat,C}_n_mult
  4473   starfun_n_add <-- starfun{Nat,C}_n_add
  4474   starfun_n_add_minus <-- starfunNat_n_add_minus
  4475   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  4476   starfun_n_minus <-- starfun{Nat,C}_n_minus
  4477   starfun_n_eq <-- starfun{Nat,C}_n_eq
  4478 
  4479   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  4480   star_n_minus <-- {hypreal,hcomplex}_minus
  4481   star_n_diff <-- {hypreal,hcomplex}_diff
  4482   star_n_mult <-- {hypreal,hcomplex}_mult
  4483   star_n_inverse <-- {hypreal,hcomplex}_inverse
  4484   star_n_le <-- {hypreal,hypnat}_le
  4485   star_n_less <-- {hypreal,hypnat}_less
  4486   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  4487   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  4488   star_n_abs <-- hypreal_hrabs
  4489   star_n_divide <-- hcomplex_divide
  4490 
  4491   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  4492   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  4493   star_of_diff <-- hypreal_of_real_diff
  4494   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  4495   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  4496   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  4497   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  4498   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  4499   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  4500   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  4501   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  4502   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  4503   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  4504   star_of_number_of <-- {hypreal,hcomplex}_number_of
  4505   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  4506   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  4507   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  4508   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  4509   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  4510   star_of_power <-- hypreal_of_real_power
  4511   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  4512 
  4513 * Hyperreal: new method "transfer" that implements the transfer
  4514 principle of nonstandard analysis. With a subgoal that mentions
  4515 nonstandard types like "'a star", the command "apply transfer"
  4516 replaces it with an equivalent one that mentions only standard types.
  4517 To be successful, all free variables must have standard types; non-
  4518 standard variables must have explicit universal quantifiers.
  4519 
  4520 * Hyperreal: A theory of Taylor series.
  4521 
  4522 
  4523 *** HOLCF ***
  4524 
  4525 * Discontinued special version of 'constdefs' (which used to support
  4526 continuous functions) in favor of the general Pure one with full
  4527 type-inference.
  4528 
  4529 * New simplification procedure for solving continuity conditions; it
  4530 is much faster on terms with many nested lambda abstractions (cubic
  4531 instead of exponential time).
  4532 
  4533 * New syntax for domain package: selector names are now optional.
  4534 Parentheses should be omitted unless argument is lazy, for example:
  4535 
  4536   domain 'a stream = cons "'a" (lazy "'a stream")
  4537 
  4538 * New command 'fixrec' for defining recursive functions with pattern
  4539 matching; defining multiple functions with mutual recursion is also
  4540 supported.  Patterns may include the constants cpair, spair, up, sinl,
  4541 sinr, or any data constructor defined by the domain package. The given
  4542 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  4543 syntax and examples.
  4544 
  4545 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  4546 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  4547 but the proof obligation additionally includes an admissibility
  4548 requirement. The packages generate instances of class cpo or pcpo,
  4549 with continuity and strictness theorems for Rep and Abs.
  4550 
  4551 * HOLCF: Many theorems have been renamed according to a more standard naming
  4552 scheme (INCOMPATIBILITY):
  4553 
  4554   foo_inject:  "foo$x = foo$y ==> x = y"
  4555   foo_eq:      "(foo$x = foo$y) = (x = y)"
  4556   foo_less:    "(foo$x << foo$y) = (x << y)"
  4557   foo_strict:  "foo$UU = UU"
  4558   foo_defined: "... ==> foo$x ~= UU"
  4559   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  4560 
  4561 
  4562 *** ZF ***
  4563 
  4564 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  4565 including the First Isomorphism Theorem (on quotienting by the kernel
  4566 of a homomorphism).
  4567 
  4568 * ZF/Simplifier: install second copy of type solver that actually
  4569 makes use of TC rules declared to Isar proof contexts (or locales);
  4570 the old version is still required for ML proof scripts.
  4571 
  4572 
  4573 *** Cube ***
  4574 
  4575 * Converted to Isar theory format; use locales instead of axiomatic
  4576 theories.
  4577 
  4578 
  4579 *** ML ***
  4580 
  4581 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  4582 for ||>, ||>>, |>>,
  4583 
  4584 * Pure/library.ML no longer defines its own option datatype, but uses
  4585 that of the SML basis, which has constructors NONE and SOME instead of
  4586 None and Some, as well as exception Option.Option instead of OPTION.
  4587 The functions the, if_none, is_some, is_none have been adapted
  4588 accordingly, while Option.map replaces apsome.
  4589 
  4590 * Pure/library.ML: the exception LIST has been given up in favour of
  4591 the standard exceptions Empty and Subscript, as well as
  4592 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  4593 superceded by the standard hd and tl functions etc.
  4594 
  4595 A number of basic list functions are no longer exported to the ML
  4596 toplevel, as they are variants of predefined functions.  The following
  4597 suggests how one can translate existing code:
  4598 
  4599     rev_append xs ys = List.revAppend (xs, ys)
  4600     nth_elem (i, xs) = List.nth (xs, i)
  4601     last_elem xs = List.last xs
  4602     flat xss = List.concat xss
  4603     seq fs = List.app fs
  4604     partition P xs = List.partition P xs
  4605     mapfilter f xs = List.mapPartial f xs
  4606 
  4607 * Pure/library.ML: several combinators for linear functional
  4608 transformations, notably reverse application and composition:
  4609 
  4610   x |> f                f #> g
  4611   (x, y) |-> f          f #-> g
  4612 
  4613 * Pure/library.ML: introduced/changed precedence of infix operators:
  4614 
  4615   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  4616   infix 2 ?;
  4617   infix 3 o oo ooo oooo;
  4618   infix 4 ~~ upto downto;
  4619 
  4620 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  4621 infix operators.
  4622 
  4623 * Pure/library.ML: natural list combinators fold, fold_rev, and
  4624 fold_map support linear functional transformations and nesting.  For
  4625 example:
  4626 
  4627   fold f [x1, ..., xN] y =
  4628     y |> f x1 |> ... |> f xN
  4629 
  4630   (fold o fold) f [xs1, ..., xsN] y =
  4631     y |> fold f xs1 |> ... |> fold f xsN
  4632 
  4633   fold f [x1, ..., xN] =
  4634     f x1 #> ... #> f xN
  4635 
  4636   (fold o fold) f [xs1, ..., xsN] =
  4637     fold f xs1 #> ... #> fold f xsN
  4638 
  4639 * Pure/library.ML: the following selectors on type 'a option are
  4640 available:
  4641 
  4642   the:               'a option -> 'a  (*partial*)
  4643   these:             'a option -> 'a  where 'a = 'b list
  4644   the_default: 'a -> 'a option -> 'a
  4645   the_list:          'a option -> 'a list
  4646 
  4647 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  4648 basic operations for association lists, following natural argument
  4649 order; moreover the explicit equality predicate passed here avoids
  4650 potentially expensive polymorphic runtime equality checks.
  4651 The old functions may be expressed as follows:
  4652 
  4653   assoc = uncurry (AList.lookup (op =))
  4654   assocs = these oo AList.lookup (op =)
  4655   overwrite = uncurry (AList.update (op =)) o swap
  4656 
  4657 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  4658 
  4659   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  4660   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  4661 
  4662 replacing make_keylist and keyfilter (occassionally used)
  4663 Naive rewrites:
  4664 
  4665   make_keylist = AList.make
  4666   keyfilter = AList.find (op =)
  4667 
  4668 * eq_fst and eq_snd now take explicit equality parameter, thus
  4669   avoiding eqtypes. Naive rewrites:
  4670 
  4671     eq_fst = eq_fst (op =)
  4672     eq_snd = eq_snd (op =)
  4673 
  4674 * Removed deprecated apl and apr (rarely used).
  4675   Naive rewrites:
  4676 
  4677     apl (n, op) =>>= curry op n
  4678     apr (op, m) =>>= fn n => op (n, m)
  4679 
  4680 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  4681 provides a reasonably efficient light-weight implementation of sets as
  4682 lists.
  4683 
  4684 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  4685 few new operations; existing lookup and update are now curried to
  4686 follow natural argument order (for use with fold etc.);
  4687 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  4688 
  4689 * Pure/General: output via the Isabelle channels of
  4690 writeln/warning/error etc. is now passed through Output.output, with a
  4691 hook for arbitrary transformations depending on the print_mode
  4692 (cf. Output.add_mode -- the first active mode that provides a output
  4693 function wins).  Already formatted output may be embedded into further
  4694 text via Output.raw; the result of Pretty.string_of/str_of and derived
  4695 functions (string_of_term/cterm/thm etc.) is already marked raw to
  4696 accommodate easy composition of diagnostic messages etc.  Programmers
  4697 rarely need to care about Output.output or Output.raw at all, with
  4698 some notable exceptions: Output.output is required when bypassing the
  4699 standard channels (writeln etc.), or in token translations to produce
  4700 properly formatted results; Output.raw is required when capturing
  4701 already output material that will eventually be presented to the user
  4702 a second time.  For the default print mode, both Output.output and
  4703 Output.raw have no effect.
  4704 
  4705 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  4706 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  4707 cumulative results are displayed at the end of a batch session.
  4708 
  4709 * Pure/General: File.sysify_path and File.quote_sysify path have been
  4710 replaced by File.platform_path and File.shell_path (with appropriate
  4711 hooks).  This provides a clean interface for unusual systems where the
  4712 internal and external process view of file names are different.
  4713 
  4714 * Pure: more efficient orders for basic syntactic entities: added
  4715 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  4716 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  4717 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  4718 orders now -- potential INCOMPATIBILITY for code that depends on a
  4719 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  4720 Library.sort_strings on result).
  4721 
  4722 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  4723 fold_types traverse types/terms from left to right, observing natural
  4724 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  4725 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  4726 
  4727 * Pure: name spaces have been refined, with significant changes of the
  4728 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  4729 to extern(_table).  The plain name entry path is superceded by a
  4730 general 'naming' context, which also includes the 'policy' to produce
  4731 a fully qualified name and external accesses of a fully qualified
  4732 name; NameSpace.extend is superceded by context dependent
  4733 Sign.declare_name.  Several theory and proof context operations modify
  4734 the naming context.  Especially note Theory.restore_naming and
  4735 ProofContext.restore_naming to get back to a sane state; note that
  4736 Theory.add_path is no longer sufficient to recover from
  4737 Theory.absolute_path in particular.
  4738 
  4739 * Pure: new flags short_names (default false) and unique_names
  4740 (default true) for controlling output of qualified names.  If
  4741 short_names is set, names are printed unqualified.  If unique_names is
  4742 reset, the name prefix is reduced to the minimum required to achieve
  4743 the original result when interning again, even if there is an overlap
  4744 with earlier declarations.
  4745 
  4746 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  4747 now 'extend', and 'merge' gets an additional Pretty.pp argument
  4748 (useful for printing error messages).  INCOMPATIBILITY.
  4749 
  4750 * Pure: major reorganization of the theory context.  Type Sign.sg and
  4751 Theory.theory are now identified, referring to the universal
  4752 Context.theory (see Pure/context.ML).  Actual signature and theory
  4753 content is managed as theory data.  The old code and interfaces were
  4754 spread over many files and structures; the new arrangement introduces
  4755 considerable INCOMPATIBILITY to gain more clarity:
  4756 
  4757   Context -- theory management operations (name, identity, inclusion,
  4758     parents, ancestors, merge, etc.), plus generic theory data;
  4759 
  4760   Sign -- logical signature and syntax operations (declaring consts,
  4761     types, etc.), plus certify/read for common entities;
  4762 
  4763   Theory -- logical theory operations (stating axioms, definitions,
  4764     oracles), plus a copy of logical signature operations (consts,
  4765     types, etc.); also a few basic management operations (Theory.copy,
  4766     Theory.merge, etc.)
  4767 
  4768 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  4769 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  4770 for convenience -- they merely return the theory.
  4771 
  4772 * Pure: type Type.tsig is superceded by theory in most interfaces.
  4773 
  4774 * Pure: the Isar proof context type is already defined early in Pure
  4775 as Context.proof (note that ProofContext.context and Proof.context are
  4776 aliases, where the latter is the preferred name).  This enables other
  4777 Isabelle components to refer to that type even before Isar is present.
  4778 
  4779 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  4780 typeK, constK, axiomK, oracleK), but provide explicit operations for
  4781 any of these kinds.  For example, Sign.intern typeK is now
  4782 Sign.intern_type, Theory.hide_space Sign.typeK is now
  4783 Theory.hide_types.  Also note that former
  4784 Theory.hide_classes/types/consts are now
  4785 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  4786 internalize their arguments!  INCOMPATIBILITY.
  4787 
  4788 * Pure: get_thm interface (of PureThy and ProofContext) expects
  4789 datatype thmref (with constructors Name and NameSelection) instead of
  4790 plain string -- INCOMPATIBILITY;
  4791 
  4792 * Pure: cases produced by proof methods specify options, where NONE
  4793 means to remove case bindings -- INCOMPATIBILITY in
  4794 (RAW_)METHOD_CASES.
  4795 
  4796 * Pure: the following operations retrieve axioms or theorems from a
  4797 theory node or theory hierarchy, respectively:
  4798 
  4799   Theory.axioms_of: theory -> (string * term) list
  4800   Theory.all_axioms_of: theory -> (string * term) list
  4801   PureThy.thms_of: theory -> (string * thm) list
  4802   PureThy.all_thms_of: theory -> (string * thm) list
  4803 
  4804 * Pure: print_tac now outputs the goal through the trace channel.
  4805 
  4806 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  4807 Reference Toplevel.debug (default false) controls detailed printing
  4808 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  4809 controls execution profiling -- set to 1 for time and 2 for space
  4810 (both increase the runtime).
  4811 
  4812 * Isar session: The initial use of ROOT.ML is now always timed,
  4813 i.e. the log will show the actual process times, in contrast to the
  4814 elapsed wall-clock time that the outer shell wrapper produces.
  4815 
  4816 * Simplifier: improved handling of bound variables (nameless
  4817 representation, avoid allocating new strings).  Simprocs that invoke
  4818 the Simplifier recursively should use Simplifier.inherit_bounds to
  4819 avoid local name clashes.  Failure to do so produces warnings
  4820 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  4821 for further details.
  4822 
  4823 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  4824 bindings for all theorems stored within a given theory; this may help
  4825 in porting non-Isar theories to Isar ones, while keeping ML proof
  4826 scripts for the time being.
  4827 
  4828 * ML operator HTML.with_charset specifies the charset begin used for
  4829 generated HTML files.  For example:
  4830 
  4831   HTML.with_charset "utf-8" use_thy "Hebrew";
  4832   HTML.with_charset "utf-8" use_thy "Chinese";
  4833 
  4834 
  4835 *** System ***
  4836 
  4837 * Allow symlinks to all proper Isabelle executables (Isabelle,
  4838 isabelle, isatool etc.).
  4839 
  4840 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  4841 isatool doc, isatool mkdir, display_drafts etc.).
  4842 
  4843 * isatool usedir: option -f allows specification of the ML file to be
  4844 used by Isabelle; default is ROOT.ML.
  4845 
  4846 * New isatool version outputs the version identifier of the Isabelle
  4847 distribution being used.
  4848 
  4849 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  4850 (containing Boolean satisfiability problems) into Isabelle/HOL
  4851 theories.
  4852 
  4853 
  4854 
  4855 New in Isabelle2004 (April 2004)
  4856 --------------------------------
  4857 
  4858 *** General ***
  4859 
  4860 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  4861   Replaces linorder.ML.
  4862 
  4863 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  4864   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  4865   (\<a>...\<z>), are now considered normal letters, and can therefore
  4866   be used anywhere where an ASCII letter (a...zA...Z) has until
  4867   now. COMPATIBILITY: This obviously changes the parsing of some
  4868   terms, especially where a symbol has been used as a binder, say
  4869   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  4870   as an identifier.  Fix it by inserting a space around former
  4871   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  4872   existing theory and ML files.
  4873 
  4874 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  4875 
  4876 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  4877   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  4878   a normal (but invisible) letter. For multiple letter subscripts repeat
  4879   \<^isub> like this: x\<^isub>1\<^isub>2.
  4880 
  4881 * Pure: There are now sub-/superscripts that can span more than one
  4882   character. Text between \<^bsub> and \<^esub> is set in subscript in
  4883   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  4884   superscript. The new control characters are not identifier parts.
  4885 
  4886 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  4887   content of "..." to the latex file instead of \isacntrl... . The "..."
  4888   may consist of any printable characters excluding the end bracket >.
  4889 
  4890 * Pure: Using new Isar command "finalconsts" (or the ML functions
  4891   Theory.add_finals or Theory.add_finals_i) it is now possible to
  4892   declare constants "final", which prevents their being given a definition
  4893   later.  It is useful for constants whose behaviour is fixed axiomatically
  4894   rather than definitionally, such as the meta-logic connectives.
  4895 
  4896 * Pure: 'instance' now handles general arities with general sorts
  4897   (i.e. intersections of classes),
  4898 
  4899 * Presentation: generated HTML now uses a CSS style sheet to make layout
  4900   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  4901   It can be changed to alter the colors/layout of generated pages.
  4902 
  4903 
  4904 *** Isar ***
  4905 
  4906 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  4907   cut_tac, subgoal_tac and thin_tac:
  4908   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  4909     locales are no longer forced to write Isar proof scripts.
  4910     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  4911     emulations.
  4912   - INCOMPATIBILITY: names of variables to be instantiated may no
  4913     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  4914     This is consistent with the instantiation attribute "where".
  4915 
  4916 * Attributes "where" and "of":
  4917   - Now take type variables of instantiated theorem into account when reading
  4918     the instantiation string.  This fixes a bug that caused instantiated
  4919     theorems to have too special types in some circumstances.
  4920   - "where" permits explicit instantiations of type variables.
  4921 
  4922 * Calculation commands "moreover" and "also" no longer interfere with
  4923   current facts ("this"), admitting arbitrary combinations with "then"
  4924   and derived forms.
  4925 
  4926 * Locales:
  4927   - Goal statements involving the context element "includes" no longer
  4928     generate theorems with internal delta predicates (those ending on
  4929     "_axioms") in the premise.
  4930     Resolve particular premise with <locale>.intro to obtain old form.
  4931   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  4932     specification and "includes" elements in goal statement.
  4933   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  4934     [intro?] and [elim?] (respectively) by default.
  4935   - Experimental command for instantiation of locales in proof contexts:
  4936         instantiate <label>[<attrs>]: <loc>
  4937     Instantiates locale <loc> and adds all its theorems to the current context
  4938     taking into account their attributes.  Label and attrs are optional
  4939     modifiers, like in theorem declarations.  If present, names of
  4940     instantiated theorems are qualified with <label>, and the attributes
  4941     <attrs> are applied after any attributes these theorems might have already.
  4942       If the locale has assumptions, a chained fact of the form
  4943     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  4944     are derived.  The command does not support old-style locales declared
  4945     with "locale (open)".
  4946       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  4947 
  4948 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  4949   (Isar) contexts.
  4950 
  4951 
  4952 *** HOL ***
  4953 
  4954 * Proof import: new image HOL4 contains the imported library from
  4955   the HOL4 system with about 2500 theorems. It is imported by
  4956   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  4957   can be used like any other Isabelle image.  See
  4958   HOL/Import/HOL/README for more information.
  4959 
  4960 * Simplifier:
  4961   - Much improved handling of linear and partial orders.
  4962     Reasoners for linear and partial orders are set up for type classes
  4963     "linorder" and "order" respectively, and are added to the default simpset
  4964     as solvers.  This means that the simplifier can build transitivity chains
  4965     to solve goals from the assumptions.
  4966   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  4967     of blast or auto after simplification become unnecessary because the goal
  4968     is solved by simplification already.
  4969 
  4970 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  4971     all proved in axiomatic type classes for semirings, rings and fields.
  4972 
  4973 * Numerics:
  4974   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  4975     now formalized using the Ring_and_Field theory mentioned above.
  4976   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  4977     than before, because now they are set up once in a generic manner.
  4978   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  4979     Look for the general versions in Ring_and_Field (and Power if they concern
  4980     exponentiation).
  4981 
  4982 * Type "rat" of the rational numbers is now available in HOL-Complex.
  4983 
  4984 * Records:
  4985   - Record types are now by default printed with their type abbreviation
  4986     instead of the list of all field types. This can be configured via
  4987     the reference "print_record_type_abbr".
  4988   - Simproc "record_upd_simproc" for simplification of multiple updates added
  4989     (not enabled by default).
  4990   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  4991     EX x. x = sel r to True (not enabled by default).
  4992   - Tactic "record_split_simp_tac" to split and simplify records added.
  4993 
  4994 * 'specification' command added, allowing for definition by
  4995   specification.  There is also an 'ax_specification' command that
  4996   introduces the new constants axiomatically.
  4997 
  4998 * arith(_tac) is now able to generate counterexamples for reals as well.
  4999 
  5000 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5001 
  5002 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5003   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5004 
  5005 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5006   matrix theory to linear programming.
  5007 
  5008 * Unions and Intersections:
  5009   The latex output syntax of UN and INT has been changed
  5010   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5011   i.e. the index formulae has become a subscript.
  5012   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5013 
  5014 * Unions and Intersections over Intervals:
  5015   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5016   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5017   like in normal math, and corresponding versions for < and for intersection.
  5018 
  5019 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5020   lexicographic dictonary ordering has been added as "lexord".
  5021 
  5022 * ML: the legacy theory structures Int and List have been removed. They had
  5023   conflicted with ML Basis Library structures having the same names.
  5024 
  5025 * 'refute' command added to search for (finite) countermodels.  Only works
  5026   for a fragment of HOL.  The installation of an external SAT solver is
  5027   highly recommended.  See "HOL/Refute.thy" for details.
  5028 
  5029 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5030   formulae under an assignment of free variables to random values.
  5031   In contrast to 'refute', it can deal with inductive datatypes,
  5032   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5033   for examples.
  5034 
  5035 
  5036 *** HOLCF ***
  5037 
  5038 * Streams now come with concatenation and are part of the HOLCF image
  5039 
  5040 
  5041 
  5042 New in Isabelle2003 (May 2003)
  5043 ------------------------------
  5044 
  5045 *** General ***
  5046 
  5047 * Provers/simplifier:
  5048 
  5049   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5050     Assumptions are now subject to complete mutual simplification,
  5051     not just from left to right. The simplifier now preserves
  5052     the order of assumptions.
  5053 
  5054     Potential INCOMPATIBILITY:
  5055 
  5056     -- simp sometimes diverges where the old version did
  5057        not, e.g. invoking simp on the goal
  5058 
  5059         [| P (f x); y = x; f x = f y |] ==> Q
  5060 
  5061        now gives rise to the infinite reduction sequence
  5062 
  5063         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5064 
  5065        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5066        kind of problem.
  5067 
  5068     -- Tactics combining classical reasoner and simplification (such as auto)
  5069        are also affected by this change, because many of them rely on
  5070        simp. They may sometimes diverge as well or yield a different numbers
  5071        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5072        in case of problems. Sometimes subsequent calls to the classical
  5073        reasoner will fail because a preceeding call to the simplifier too
  5074        eagerly simplified the goal, e.g. deleted redundant premises.
  5075 
  5076   - The simplifier trace now shows the names of the applied rewrite rules
  5077 
  5078   - You can limit the number of recursive invocations of the simplifier
  5079     during conditional rewriting (where the simplifie tries to solve the
  5080     conditions before applying the rewrite rule):
  5081     ML "simp_depth_limit := n"
  5082     where n is an integer. Thus you can force termination where previously
  5083     the simplifier would diverge.
  5084 
  5085   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5086 
  5087   - No longer aborts on failed congruence proof.  Instead, the
  5088     congruence is ignored.
  5089 
  5090 * Pure: New generic framework for extracting programs from constructive
  5091   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5092   as HOL/Extraction for some case studies.
  5093 
  5094 * Pure: The main goal of the proof state is no longer shown by default, only
  5095 the subgoals. This behaviour is controlled by a new flag.
  5096    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5097 (ML: Proof.show_main_goal).
  5098 
  5099 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5100 rules whose conclusion matches subgoal 1:
  5101       PG menu: Isabelle/Isar -> Show me -> matching rules
  5102 The rules are ordered by how closely they match the subgoal.
  5103 In particular, rules that solve a subgoal outright are displayed first
  5104 (or rather last, the way they are printed).
  5105 (ML: ProofGeneral.print_intros())
  5106 
  5107 * Pure: New flag trace_unify_fail causes unification to print
  5108 diagnostic information (PG: in trace buffer) when it fails. This is
  5109 useful for figuring out why single step proofs like rule, erule or
  5110 assumption failed.
  5111 
  5112 * Pure: Locale specifications now produce predicate definitions
  5113 according to the body of text (covering assumptions modulo local
  5114 definitions); predicate "loc_axioms" covers newly introduced text,
  5115 while "loc" is cumulative wrt. all included locale expressions; the
  5116 latter view is presented only on export into the global theory
  5117 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5118 on the old view without predicates;
  5119 
  5120 * Pure: predefined locales "var" and "struct" are useful for sharing
  5121 parameters (as in CASL, for example); just specify something like
  5122 ``var x + var y + struct M'' as import;
  5123 
  5124 * Pure: improved thms_containing: proper indexing of facts instead of
  5125 raw theorems; check validity of results wrt. current name space;
  5126 include local facts of proof configuration (also covers active
  5127 locales), cover fixed variables in index; may use "_" in term
  5128 specification; an optional limit for the number of printed facts may
  5129 be given (the default is 40);
  5130 
  5131 * Pure: disallow duplicate fact bindings within new-style theory files
  5132 (batch-mode only);
  5133 
  5134 * Provers: improved induct method: assumptions introduced by case
  5135 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5136 the goal statement); "foo" still refers to all facts collectively;
  5137 
  5138 * Provers: the function blast.overloaded has been removed: all constants
  5139 are regarded as potentially overloaded, which improves robustness in exchange
  5140 for slight decrease in efficiency;
  5141 
  5142 * Provers/linorder: New generic prover for transitivity reasoning over
  5143 linear orders.  Note: this prover is not efficient!
  5144 
  5145 * Isar: preview of problems to finish 'show' now produce an error
  5146 rather than just a warning (in interactive mode);
  5147 
  5148 
  5149 *** HOL ***
  5150 
  5151 * arith(_tac)
  5152 
  5153  - Produces a counter example if it cannot prove a goal.
  5154    Note that the counter example may be spurious if the goal is not a formula
  5155    of quantifier-free linear arithmetic.
  5156    In ProofGeneral the counter example appears in the trace buffer.
  5157 
  5158  - Knows about div k and mod k where k is a numeral of type nat or int.
  5159 
  5160  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5161    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5162    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5163 
  5164 * simp's arithmetic capabilities have been enhanced a bit: it now
  5165 takes ~= in premises into account (by performing a case split);
  5166 
  5167 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5168 are distributed over a sum of terms;
  5169 
  5170 * New tactic "trans_tac" and method "trans" instantiate
  5171 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5172 "<=", "<" and "=").
  5173 
  5174 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5175 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5176 
  5177 * 'typedef' command has new option "open" to suppress the set
  5178 definition;
  5179 
  5180 * functions Min and Max on finite sets have been introduced (theory
  5181 Finite_Set);
  5182 
  5183 * attribute [symmetric] now works for relations as well; it turns
  5184 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5185 
  5186 * induct over a !!-quantified statement (say !!x1..xn):
  5187   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5188 
  5189 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5190 %x. None. Warning: empty_def now refers to the previously hidden definition
  5191 of the empty set.
  5192 
  5193 * Algebra: formalization of classical algebra.  Intended as base for
  5194 any algebraic development in Isabelle.  Currently covers group theory
  5195 (up to Sylow's theorem) and ring theory (Universal Property of
  5196 Univariate Polynomials).  Contributions welcome;
  5197 
  5198 * GroupTheory: deleted, since its material has been moved to Algebra;
  5199 
  5200 * Complex: new directory of the complex numbers with numeric constants,
  5201 nonstandard complex numbers, and some complex analysis, standard and
  5202 nonstandard (Jacques Fleuriot);
  5203 
  5204 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  5205 
  5206 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  5207 Fleuriot);
  5208 
  5209 * Real/HahnBanach: updated and adapted to locales;
  5210 
  5211 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  5212 Gray and Kramer);
  5213 
  5214 * UNITY: added the Meier-Sanders theory of progress sets;
  5215 
  5216 * MicroJava: bytecode verifier and lightweight bytecode verifier
  5217 as abstract algorithms, instantiated to the JVM;
  5218 
  5219 * Bali: Java source language formalization. Type system, operational
  5220 semantics, axiomatic semantics. Supported language features:
  5221 classes, interfaces, objects,virtual methods, static methods,
  5222 static/instance fields, arrays, access modifiers, definite
  5223 assignment, exceptions.
  5224 
  5225 
  5226 *** ZF ***
  5227 
  5228 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  5229 universe, etc.);
  5230 
  5231 * Main ZF: virtually all theories converted to new-style format;
  5232 
  5233 
  5234 *** ML ***
  5235 
  5236 * Pure: Tactic.prove provides sane interface for internal proofs;
  5237 omits the infamous "standard" operation, so this is more appropriate
  5238 than prove_goalw_cterm in many situations (e.g. in simprocs);
  5239 
  5240 * Pure: improved error reporting of simprocs;
  5241 
  5242 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  5243 up simprocs;
  5244 
  5245 
  5246 *** Document preparation ***
  5247 
  5248 * uses \par instead of \\ for line breaks in theory text. This may
  5249 shift some page breaks in large documents. To get the old behaviour
  5250 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  5251 
  5252 * minimized dependencies of isabelle.sty and isabellesym.sty on
  5253 other packages
  5254 
  5255 * \<euro> now needs package babel/greek instead of marvosym (which
  5256 broke \Rightarrow)
  5257 
  5258 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  5259 textcomp package)
  5260 
  5261 
  5262 
  5263 New in Isabelle2002 (March 2002)
  5264 --------------------------------
  5265 
  5266 *** Document preparation ***
  5267 
  5268 * greatly simplified document preparation setup, including more
  5269 graceful interpretation of isatool usedir -i/-d/-D options, and more
  5270 instructive isatool mkdir; users should basically be able to get
  5271 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  5272 users may run a separate document processing stage manually like this:
  5273 "isatool usedir -D output HOL Test && isatool document Test/output";
  5274 
  5275 * theory dependency graph may now be incorporated into documents;
  5276 isatool usedir -g true will produce session_graph.eps/.pdf for use
  5277 with \includegraphics of LaTeX;
  5278 
  5279 * proper spacing of consecutive markup elements, especially text
  5280 blocks after section headings;
  5281 
  5282 * support bold style (for single symbols only), input syntax is like
  5283 this: "\<^bold>\<alpha>" or "\<^bold>A";
  5284 
  5285 * \<bullet> is now output as bold \cdot by default, which looks much
  5286 better in printed text;
  5287 
  5288 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  5289 note that these symbols are currently unavailable in Proof General /
  5290 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  5291 
  5292 * isatool latex no longer depends on changed TEXINPUTS, instead
  5293 isatool document copies the Isabelle style files to the target
  5294 location;
  5295 
  5296 
  5297 *** Isar ***
  5298 
  5299 * Pure/Provers: improved proof by cases and induction;
  5300   - 'case' command admits impromptu naming of parameters (such as
  5301     "case (Suc n)");
  5302   - 'induct' method divinates rule instantiation from the inductive
  5303     claim; no longer requires excessive ?P bindings for proper
  5304     instantiation of cases;
  5305   - 'induct' method properly enumerates all possibilities of set/type
  5306     rules; as a consequence facts may be also passed through *type*
  5307     rules without further ado;
  5308   - 'induct' method now derives symbolic cases from the *rulified*
  5309     rule (before it used to rulify cases stemming from the internal
  5310     atomized version); this means that the context of a non-atomic
  5311     statement becomes is included in the hypothesis, avoiding the
  5312     slightly cumbersome show "PROP ?case" form;
  5313   - 'induct' may now use elim-style induction rules without chaining
  5314     facts, using ``missing'' premises from the goal state; this allows
  5315     rules stemming from inductive sets to be applied in unstructured
  5316     scripts, while still benefitting from proper handling of non-atomic
  5317     statements; NB: major inductive premises need to be put first, all
  5318     the rest of the goal is passed through the induction;
  5319   - 'induct' proper support for mutual induction involving non-atomic
  5320     rule statements (uses the new concept of simultaneous goals, see
  5321     below);
  5322   - append all possible rule selections, but only use the first
  5323     success (no backtracking);
  5324   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  5325   - undeclared rule case names default to numbers 1, 2, 3, ...;
  5326   - added 'print_induct_rules' (covered by help item in recent Proof
  5327     General versions);
  5328   - moved induct/cases attributes to Pure, methods to Provers;
  5329   - generic method setup instantiated for FOL and HOL;
  5330 
  5331 * Pure: support multiple simultaneous goal statements, for example
  5332 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  5333 meta-level mechanism, this acts as if several individual goals had
  5334 been stated separately; in particular common proof methods need to be
  5335 repeated in order to cover all claims; note that a single elimination
  5336 step is *not* sufficient to establish the two conjunctions, so this
  5337 fails:
  5338 
  5339   assume "A & B" then have A and B ..   (*".." fails*)
  5340 
  5341 better use "obtain" in situations as above; alternative refer to
  5342 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  5343 
  5344 * Pure: proper integration with ``locales''; unlike the original
  5345 version by Florian Kammller, Isar locales package high-level proof
  5346 contexts rather than raw logical ones (e.g. we admit to include
  5347 attributes everywhere); operations on locales include merge and
  5348 rename; support for implicit arguments (``structures''); simultaneous
  5349 type-inference over imports and text; see also HOL/ex/Locales.thy for
  5350 some examples;
  5351 
  5352 * Pure: the following commands have been ``localized'', supporting a
  5353 target locale specification "(in name)": 'lemma', 'theorem',
  5354 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  5355 stored both within the locale and at the theory level (exported and
  5356 qualified by the locale name);
  5357 
  5358 * Pure: theory goals may now be specified in ``long'' form, with
  5359 ad-hoc contexts consisting of arbitrary locale elements. for example
  5360 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  5361 definitions may be given, too); the result is a meta-level rule with
  5362 the context elements being discharged in the obvious way;
  5363 
  5364 * Pure: new proof command 'using' allows to augment currently used
  5365 facts after a goal statement ('using' is syntactically analogous to
  5366 'apply', but acts on the goal's facts only); this allows chained facts
  5367 to be separated into parts given before and after a claim, as in
  5368 ``from a and b have C using d and e <proof>'';
  5369 
  5370 * Pure: renamed "antecedent" case to "rule_context";
  5371 
  5372 * Pure: new 'judgment' command records explicit information about the
  5373 object-logic embedding (used by several tools internally); no longer
  5374 use hard-wired "Trueprop";
  5375 
  5376 * Pure: added 'corollary' command;
  5377 
  5378 * Pure: fixed 'token_translation' command;
  5379 
  5380 * Pure: removed obsolete 'exported' attribute;
  5381 
  5382 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  5383 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  5384 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  5385 
  5386 * Pure: method 'atomize' presents local goal premises as object-level
  5387 statements (atomic meta-level propositions); setup controlled via
  5388 rewrite rules declarations of 'atomize' attribute; example
  5389 application: 'induct' method with proper rule statements in improper
  5390 proof *scripts*;
  5391 
  5392 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  5393 now consider the syntactic context of assumptions, giving a better
  5394 chance to get type-inference of the arguments right (this is
  5395 especially important for locales);
  5396 
  5397 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  5398 mode;
  5399 
  5400 * Pure/obtain: the formal conclusion "thesis", being marked as
  5401 ``internal'', may no longer be reference directly in the text;
  5402 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  5403 situations;
  5404 
  5405 * Pure: generic 'sym' attribute which declares a rule both as pure
  5406 'elim?' and for the 'symmetric' operation;
  5407 
  5408 * Pure: marginal comments ``--'' may now occur just anywhere in the
  5409 text; the fixed correlation with particular command syntax has been
  5410 discontinued;
  5411 
  5412 * Pure: new method 'rules' is particularly well-suited for proof
  5413 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  5414 but often produces more compact proof terms with less detours;
  5415 
  5416 * Pure/Provers/classical: simplified integration with pure rule
  5417 attributes and methods; the classical "intro?/elim?/dest?"
  5418 declarations coincide with the pure ones; the "rule" method no longer
  5419 includes classically swapped intros; "intro" and "elim" methods no
  5420 longer pick rules from the context; also got rid of ML declarations
  5421 AddXIs/AddXEs/AddXDs; all of this has some potential for
  5422 INCOMPATIBILITY;
  5423 
  5424 * Provers/classical: attribute 'swapped' produces classical inversions
  5425 of introduction rules;
  5426 
  5427 * Provers/simplifier: 'simplified' attribute may refer to explicit
  5428 rules instead of full simplifier context; 'iff' attribute handles
  5429 conditional rules;
  5430 
  5431 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  5432 
  5433 * HOL: 'recdef' now fails on unfinished automated proofs, use
  5434 "(permissive)" option to recover old behavior;
  5435 
  5436 * HOL: 'inductive' no longer features separate (collective) attributes
  5437 for 'intros' (was found too confusing);
  5438 
  5439 * HOL: properly declared induction rules less_induct and
  5440 wf_induct_rule;
  5441 
  5442 
  5443 *** HOL ***
  5444 
  5445 * HOL: moved over to sane numeral syntax; the new policy is as
  5446 follows:
  5447 
  5448   - 0 and 1 are polymorphic constants, which are defined on any
  5449   numeric type (nat, int, real etc.);
  5450 
  5451   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  5452   binary representation internally;
  5453 
  5454   - type nat has special constructor Suc, and generally prefers Suc 0
  5455   over 1::nat and Suc (Suc 0) over 2::nat;
  5456 
  5457 This change may cause significant problems of INCOMPATIBILITY; here
  5458 are some hints on converting existing sources:
  5459 
  5460   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  5461   entities, so expressions involving "-" (unary or binary minus) need
  5462   to be spaced properly;
  5463 
  5464   - existing occurrences of "1" may need to be constraint "1::nat" or
  5465   even replaced by Suc 0; similar for old "2";
  5466 
  5467   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  5468 
  5469   - remove all special provisions on numerals in proofs;
  5470 
  5471 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  5472 representation (depends on bin_arith_simps in the default context);
  5473 
  5474 * HOL: symbolic syntax for x^2 (numeral 2);
  5475 
  5476 * HOL: the class of all HOL types is now called "type" rather than
  5477 "term"; INCOMPATIBILITY, need to adapt references to this type class
  5478 in axclass/classes, instance/arities, and (usually rare) occurrences
  5479 in typings (of consts etc.); internally the class is called
  5480 "HOL.type", ML programs should refer to HOLogic.typeS;
  5481 
  5482 * HOL/record package improvements:
  5483   - new derived operations "fields" to build a partial record section,
  5484     "extend" to promote a fixed record to a record scheme, and
  5485     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  5486     declared as simp by default;
  5487   - shared operations ("more", "fields", etc.) now need to be always
  5488     qualified) --- potential INCOMPATIBILITY;
  5489   - removed "make_scheme" operations (use "make" with "extend") --
  5490     INCOMPATIBILITY;
  5491   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  5492   - provides cases/induct rules for use with corresponding Isar
  5493     methods (for concrete records, record schemes, concrete more
  5494     parts, and schematic more parts -- in that order);
  5495   - internal definitions directly based on a light-weight abstract
  5496     theory of product types over typedef rather than datatype;
  5497 
  5498 * HOL: generic code generator for generating executable ML code from
  5499 specifications; specific support for HOL constructs such as inductive
  5500 datatypes and sets, as well as recursive functions; can be invoked
  5501 via 'generate_code' theory section;
  5502 
  5503 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  5504 
  5505 * HOL: consolidated and renamed several theories.  In particular:
  5506         Ord.thy has been absorbed into HOL.thy
  5507         String.thy has been absorbed into List.thy
  5508 
  5509 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  5510 (beware of argument permutation!);
  5511 
  5512 * HOL: linorder_less_split superseded by linorder_cases;
  5513 
  5514 * HOL/List: "nodups" renamed to "distinct";
  5515 
  5516 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  5517 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  5518   - Ex_def has changed, now need to use some_eq_ex
  5519 
  5520 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  5521 in this (rare) case use:
  5522 
  5523   delSWrapper "split_all_tac"
  5524   addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
  5525 
  5526 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
  5527 MAY FAIL;
  5528 
  5529 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
  5530 Isabelle's type classes, ^ on functions and relations has too general
  5531 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be
  5532 necessary to attach explicit type constraints;
  5533 
  5534 * HOL/Relation: the prefix name of the infix "O" has been changed from
  5535 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been
  5536 renamed accordingly (eg "compI" -> "rel_compI").
  5537 
  5538 * HOL: syntax translations now work properly with numerals and records
  5539 expressions;
  5540 
  5541 * HOL: bounded abstraction now uses syntax "%" / "\<lambda>" instead
  5542 of "lam" -- INCOMPATIBILITY;
  5543 
  5544 * HOL: got rid of some global declarations (potential INCOMPATIBILITY
  5545 for ML tools): const "()" renamed "Product_Type.Unity", type "unit"
  5546 renamed "Product_Type.unit";
  5547 
  5548 * HOL: renamed rtrancl_into_rtrancl2 to converse_rtrancl_into_rtrancl
  5549 
  5550 * HOL: removed obsolete theorem "optionE" (use "option.exhaust", or
  5551 the "cases" method);
  5552 
  5553 * HOL/GroupTheory: group theory examples including Sylow's theorem (by
  5554 Florian Kammller);
  5555 
  5556 * HOL/IMP: updated and converted to new-style theory format; several
  5557 parts turned into readable document, with proper Isar proof texts and
  5558 some explanations (by Gerwin Klein);
  5559 
  5560 * HOL-Real: added Complex_Numbers (by Gertrud Bauer);
  5561 
  5562 * HOL-Hyperreal is now a logic image;
  5563 
  5564 
  5565 *** HOLCF ***
  5566 
  5567 * Isar: consts/constdefs supports mixfix syntax for continuous
  5568 operations;
  5569 
  5570 * Isar: domain package adapted to new-style theory format, e.g. see
  5571 HOLCF/ex/Dnat.thy;
  5572 
  5573 * theory Lift: proper use of rep_datatype lift instead of ML hacks --
  5574 potential INCOMPATIBILITY; now use plain induct_tac instead of former
  5575 lift.induct_tac, always use UU instead of Undef;
  5576 
  5577 * HOLCF/IMP: updated and converted to new-style theory;
  5578 
  5579 
  5580 *** ZF ***
  5581 
  5582 * Isar: proper integration of logic-specific tools and packages,
  5583 including theory commands '(co)inductive', '(co)datatype',
  5584 'rep_datatype', 'inductive_cases', as well as methods 'ind_cases',
  5585 'induct_tac', 'case_tac', and 'typecheck' (with attribute 'TC');
  5586 
  5587 * theory Main no longer includes AC; for the Axiom of Choice, base
  5588 your theory on Main_ZFC;
  5589 
  5590 * the integer library now covers quotients and remainders, with many
  5591 laws relating division to addition, multiplication, etc.;
  5592 
  5593 * ZF/UNITY: Chandy and Misra's UNITY is now available in ZF, giving a
  5594 typeless version of the formalism;
  5595 
  5596 * ZF/AC, Coind, IMP, Resid: updated and converted to new-style theory
  5597 format;
  5598 
  5599 * ZF/Induct: new directory for examples of inductive definitions,
  5600 including theory Multiset for multiset orderings; converted to
  5601 new-style theory format;
  5602 
  5603 * ZF: many new theorems about lists, ordinals, etc.;
  5604 
  5605 
  5606 *** General ***
  5607 
  5608 * Pure/kernel: meta-level proof terms (by Stefan Berghofer); reference
  5609 variable proof controls level of detail: 0 = no proofs (only oracle
  5610 dependencies), 1 = lemma dependencies, 2 = compact proof terms; see
  5611 also ref manual for further ML interfaces;
  5612 
  5613 * Pure/axclass: removed obsolete ML interface
  5614 goal_subclass/goal_arity;
  5615 
  5616 * Pure/syntax: new token syntax "num" for plain numerals (without "#"
  5617 of "xnum"); potential INCOMPATIBILITY, since -0, -1 etc. are now
  5618 separate tokens, so expressions involving minus need to be spaced
  5619 properly;
  5620 
  5621 * Pure/syntax: support non-oriented infixes, using keyword "infix"
  5622 rather than "infixl" or "infixr";
  5623 
  5624 * Pure/syntax: concrete syntax for dummy type variables admits genuine
  5625 sort constraint specifications in type inference; e.g. "x::_::foo"
  5626 ensures that the type of "x" is of sort "foo" (but not necessarily a
  5627 type variable);
  5628 
  5629 * Pure/syntax: print modes "type_brackets" and "no_type_brackets"
  5630 control output of nested => (types); the default behavior is
  5631 "type_brackets";
  5632 
  5633 * Pure/syntax: builtin parse translation for "_constify" turns valued
  5634 tokens into AST constants;
  5635 
  5636 * Pure/syntax: prefer later declarations of translations and print
  5637 translation functions; potential INCOMPATIBILITY: need to reverse
  5638 multiple declarations for same syntax element constant;
  5639 
  5640 * Pure/show_hyps reset by default (in accordance to existing Isar
  5641 practice);
  5642 
  5643 * Provers/classical: renamed addaltern to addafter, addSaltern to
  5644 addSafter;
  5645 
  5646 * Provers/clasimp: ``iff'' declarations now handle conditional rules
  5647 as well;
  5648 
  5649 * system: tested support for MacOS X; should be able to get Isabelle +
  5650 Proof General to work in a plain Terminal after installing Poly/ML
  5651 (e.g. from the Isabelle distribution area) and GNU bash alone
  5652 (e.g. from http://www.apple.com); full X11, XEmacs and X-Symbol
  5653 support requires further installations, e.g. from
  5654 http://fink.sourceforge.net/);
  5655 
  5656 * system: support Poly/ML 4.1.1 (able to manage larger heaps);
  5657 
  5658 * system: reduced base memory usage by Poly/ML (approx. 20 MB instead
  5659 of 40 MB), cf. ML_OPTIONS;
  5660 
  5661 * system: Proof General keywords specification is now part of the
  5662 Isabelle distribution (see etc/isar-keywords.el);
  5663 
  5664 * system: support for persistent Proof General sessions (refrain from
  5665 outdating all loaded theories on startup); user may create writable
  5666 logic images like this: ``isabelle -q HOL Test'';
  5667 
  5668 * system: smart selection of Isabelle process versus Isabelle
  5669 interface, accommodates case-insensitive file systems (e.g. HFS+); may
  5670 run both "isabelle" and "Isabelle" even if file names are badly
  5671 damaged (executable inspects the case of the first letter of its own
  5672 name); added separate "isabelle-process" and "isabelle-interface";
  5673 
  5674 * system: refrain from any attempt at filtering input streams; no
  5675 longer support ``8bit'' encoding of old isabelle font, instead proper
  5676 iso-latin characters may now be used; the related isatools
  5677 "symbolinput" and "nonascii" have disappeared as well;
  5678 
  5679 * system: removed old "xterm" interface (the print modes "xterm" and
  5680 "xterm_color" are still available for direct use in a suitable
  5681 terminal);
  5682 
  5683 
  5684 
  5685 New in Isabelle99-2 (February 2001)
  5686 -----------------------------------
  5687 
  5688 *** Overview of INCOMPATIBILITIES ***
  5689 
  5690 * HOL: please note that theories in the Library and elsewhere often use the
  5691 new-style (Isar) format; to refer to their theorems in an ML script you must
  5692 bind them to ML identifers by e.g.      val thm_name = thm "thm_name";
  5693 
  5694 * HOL: inductive package no longer splits induction rule aggressively,
  5695 but only as far as specified by the introductions given; the old
  5696 format may be recovered via ML function complete_split_rule or attribute
  5697 'split_rule (complete)';
  5698 
  5699 * HOL: induct renamed to lfp_induct, lfp_Tarski to lfp_unfold,
  5700 gfp_Tarski to gfp_unfold;
  5701 
  5702 * HOL: contrapos, contrapos2 renamed to contrapos_nn, contrapos_pp;
  5703 
  5704 * HOL: infix "dvd" now has priority 50 rather than 70 (because it is a
  5705 relation); infix "^^" has been renamed "``"; infix "``" has been
  5706 renamed "`"; "univalent" has been renamed "single_valued";
  5707 
  5708 * HOL/Real: "rinv" and "hrinv" replaced by overloaded "inverse"
  5709 operation;
  5710 
  5711 * HOLCF: infix "`" has been renamed "$"; the symbol syntax is \<cdot>;
  5712 
  5713 * Isar: 'obtain' no longer declares "that" fact as simp/intro;
  5714 
  5715 * Isar/HOL: method 'induct' now handles non-atomic goals; as a
  5716 consequence, it is no longer monotonic wrt. the local goal context
  5717 (which is now passed through the inductive cases);
  5718 
  5719 * Document preparation: renamed standard symbols \<ll> to \<lless> and
  5720 \<gg> to \<ggreater>;
  5721 
  5722 
  5723 *** Document preparation ***
  5724 
  5725 * \isabellestyle{NAME} selects version of Isabelle output (currently
  5726 available: are "it" for near math-mode best-style output, "sl" for
  5727 slanted text style, and "tt" for plain type-writer; if no
  5728 \isabellestyle command is given, output is according to slanted
  5729 type-writer);
  5730 
  5731 * support sub/super scripts (for single symbols only), input syntax is
  5732 like this: "A\<^sup>*" or "A\<^sup>\<star>";
  5733 
  5734 * some more standard symbols; see Appendix A of the system manual for
  5735 the complete list of symbols defined in isabellesym.sty;
  5736 
  5737 * improved isabelle style files; more abstract symbol implementation
  5738 (should now use \isamath{...} and \isatext{...} in custom symbol
  5739 definitions);
  5740 
  5741 * antiquotation @{goals} and @{subgoals} for output of *dynamic* goals
  5742 state; Note that presentation of goal states does not conform to
  5743 actual human-readable proof documents.  Please do not include goal
  5744 states into document output unless you really know what you are doing!
  5745 
  5746 * proper indentation of antiquoted output with proportional LaTeX
  5747 fonts;
  5748 
  5749 * no_document ML operator temporarily disables LaTeX document
  5750 generation;
  5751 
  5752 * isatool unsymbolize tunes sources for plain ASCII communication;
  5753 
  5754 
  5755 *** Isar ***
  5756 
  5757 * Pure: Isar now suffers initial goal statements to contain unbound
  5758 schematic variables (this does not conform to actual readable proof
  5759 documents, due to unpredictable outcome and non-compositional proof
  5760 checking); users who know what they are doing may use schematic goals
  5761 for Prolog-style synthesis of proven results;
  5762 
  5763 * Pure: assumption method (an implicit finishing) now handles actual
  5764 rules as well;
  5765 
  5766 * Pure: improved 'obtain' --- moved to Pure, insert "that" into
  5767 initial goal, declare "that" only as Pure intro (only for single
  5768 steps); the "that" rule assumption may now be involved in implicit
  5769 finishing, thus ".." becomes a feasible for trivial obtains;
  5770 
  5771 * Pure: default proof step now includes 'intro_classes'; thus trivial
  5772 instance proofs may be performed by "..";
  5773 
  5774 * Pure: ?thesis / ?this / "..." now work for pure meta-level
  5775 statements as well;
  5776 
  5777 * Pure: more robust selection of calculational rules;
  5778 
  5779 * Pure: the builtin notion of 'finished' goal now includes the ==-refl
  5780 rule (as well as the assumption rule);
  5781 
  5782 * Pure: 'thm_deps' command visualizes dependencies of theorems and
  5783 lemmas, using the graph browser tool;
  5784 
  5785 * Pure: predict failure of "show" in interactive mode;
  5786 
  5787 * Pure: 'thms_containing' now takes actual terms as arguments;
  5788 
  5789 * HOL: improved method 'induct' --- now handles non-atomic goals
  5790 (potential INCOMPATIBILITY); tuned error handling;
  5791 
  5792 * HOL: cases and induct rules now provide explicit hints about the
  5793 number of facts to be consumed (0 for "type" and 1 for "set" rules);
  5794 any remaining facts are inserted into the goal verbatim;
  5795 
  5796 * HOL: local contexts (aka cases) may now contain term bindings as
  5797 well; the 'cases' and 'induct' methods new provide a ?case binding for
  5798 the result to be shown in each case;
  5799 
  5800 * HOL: added 'recdef_tc' command;
  5801 
  5802 * isatool convert assists in eliminating legacy ML scripts;
  5803 
  5804 
  5805 *** HOL ***
  5806 
  5807 * HOL/Library: a collection of generic theories to be used together
  5808 with main HOL; the theory loader path already includes this directory
  5809 by default; the following existing theories have been moved here:
  5810 HOL/Induct/Multiset, HOL/Induct/Acc (as Accessible_Part), HOL/While
  5811 (as While_Combinator), HOL/Lex/Prefix (as List_Prefix);
  5812 
  5813 * HOL/Unix: "Some aspects of Unix file-system security", a typical
  5814 modelling and verification task performed in Isabelle/HOL +
  5815 Isabelle/Isar + Isabelle document preparation (by Markus Wenzel).
  5816 
  5817 * HOL/Algebra: special summation operator SUM no longer exists, it has
  5818 been replaced by setsum; infix 'assoc' now has priority 50 (like
  5819 'dvd'); axiom 'one_not_zero' has been moved from axclass 'ring' to
  5820 'domain', this makes the theory consistent with mathematical
  5821 literature;
  5822 
  5823 * HOL basics: added overloaded operations "inverse" and "divide"
  5824 (infix "/"), syntax for generic "abs" operation, generic summation
  5825 operator \<Sum>;
  5826 
  5827 * HOL/typedef: simplified package, provide more useful rules (see also
  5828 HOL/subset.thy);
  5829 
  5830 * HOL/datatype: induction rule for arbitrarily branching datatypes is
  5831 now expressed as a proper nested rule (old-style tactic scripts may
  5832 require atomize_strip_tac to cope with non-atomic premises);
  5833 
  5834 * HOL: renamed theory "Prod" to "Product_Type", renamed "split" rule
  5835 to "split_conv" (old name still available for compatibility);
  5836 
  5837 * HOL: improved concrete syntax for strings (e.g. allows translation
  5838 rules with string literals);
  5839 
  5840 * HOL-Real-Hyperreal: this extends HOL-Real with the hyperreals
  5841  and Fleuriot's mechanization of analysis, including the transcendental
  5842  functions for the reals;
  5843 
  5844 * HOL/Real, HOL/Hyperreal: improved arithmetic simplification;
  5845 
  5846 
  5847 *** CTT ***
  5848 
  5849 * CTT: x-symbol support for Pi, Sigma, -->, : (membership); note that
  5850 "lam" is displayed as TWO lambda-symbols
  5851 
  5852 * CTT: theory Main now available, containing everything (that is, Bool
  5853 and Arith);
  5854 
  5855 
  5856 *** General ***
  5857 
  5858 * Pure: the Simplifier has been implemented properly as a derived rule
  5859 outside of the actual kernel (at last!); the overall performance
  5860 penalty in practical applications is about 50%, while reliability of
  5861 the Isabelle inference kernel has been greatly improved;
  5862 
  5863 * print modes "brackets" and "no_brackets" control output of nested =>
  5864 (types) and ==> (props); the default behaviour is "brackets";
  5865 
  5866 * Provers: fast_tac (and friends) now handle actual object-logic rules
  5867 as assumptions as well;
  5868 
  5869 * system: support Poly/ML 4.0;
  5870 
  5871 * system: isatool install handles KDE version 1 or 2;
  5872 
  5873 
  5874 
  5875 New in Isabelle99-1 (October 2000)
  5876 ----------------------------------
  5877 
  5878 *** Overview of INCOMPATIBILITIES ***
  5879 
  5880 * HOL: simplification of natural numbers is much changed; to partly
  5881 recover the old behaviour (e.g. to prevent n+n rewriting to #2*n)
  5882 issue the following ML commands:
  5883 
  5884   Delsimprocs Nat_Numeral_Simprocs.cancel_numerals;
  5885   Delsimprocs [Nat_Numeral_Simprocs.combine_numerals];
  5886 
  5887 * HOL: simplification no longer dives into case-expressions; this is
  5888 controlled by "t.weak_case_cong" for each datatype t;
  5889 
  5890 * HOL: nat_less_induct renamed to less_induct;
  5891 
  5892 * HOL: systematic renaming of the SOME (Eps) rules, may use isatool
  5893 fixsome to patch .thy and .ML sources automatically;
  5894 
  5895   select_equality  -> some_equality
  5896   select_eq_Ex     -> some_eq_ex
  5897   selectI2EX       -> someI2_ex
  5898   selectI2         -> someI2
  5899   selectI          -> someI
  5900   select1_equality -> some1_equality
  5901   Eps_sym_eq       -> some_sym_eq_trivial
  5902   Eps_eq           -> some_eq_trivial
  5903 
  5904 * HOL: exhaust_tac on datatypes superceded by new generic case_tac;
  5905 
  5906 * HOL: removed obsolete theorem binding expand_if (refer to split_if
  5907 instead);
  5908 
  5909 * HOL: the recursion equations generated by 'recdef' are now called
  5910 f.simps instead of f.rules;
  5911 
  5912 * HOL: qed_spec_mp now also handles bounded ALL as well;
  5913 
  5914 * HOL: 0 is now overloaded, so the type constraint ":: nat" may
  5915 sometimes be needed;
  5916 
  5917 * HOL: the constant for "f``x" is now "image" rather than "op ``";
  5918 
  5919 * HOL: the constant for "f-``x" is now "vimage" rather than "op -``";
  5920 
  5921 * HOL: the disjoint sum is now "<+>" instead of "Plus"; the cartesian
  5922 product is now "<*>" instead of "Times"; the lexicographic product is
  5923 now "<*lex*>" instead of "**";
  5924 
  5925 * HOL: theory Sexp is now in HOL/Induct examples (it used to be part
  5926 of main HOL, but was unused); better use HOL's datatype package;
  5927 
  5928 * HOL: removed "symbols" syntax for constant "override" of theory Map;
  5929 the old syntax may be recovered as follows:
  5930 
  5931   syntax (symbols)
  5932     override  :: "('a ~=> 'b) => ('a ~=> 'b) => ('a ~=> 'b)"
  5933       (infixl "\\<oplus>" 100)
  5934 
  5935 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  5936 
  5937 * HOL/ML: even fewer consts are declared as global (see theories Ord,
  5938 Lfp, Gfp, WF); this only affects ML packages that refer to const names
  5939 internally;
  5940 
  5941 * HOL and ZF: syntax for quotienting wrt an equivalence relation
  5942 changed from A/r to A//r;
  5943 
  5944 * ZF: new treatment of arithmetic (nat & int) may break some old
  5945 proofs;
  5946 
  5947 * Isar: renamed some attributes (RS -> THEN, simplify -> simplified,
  5948 rulify -> rule_format, elimify -> elim_format, ...);
  5949 
  5950 * Isar/Provers: intro/elim/dest attributes changed; renamed
  5951 intro/intro!/intro!! flags to intro!/intro/intro? (in most cases, one
  5952 should have to change intro!! to intro? only); replaced "delrule" by
  5953 "rule del";
  5954 
  5955 * Isar/HOL: renamed "intrs" to "intros" in inductive definitions;
  5956 
  5957 * Provers: strengthened force_tac by using new first_best_tac;
  5958 
  5959 * LaTeX document preparation: several changes of isabelle.sty (see
  5960 lib/texinputs);
  5961 
  5962 
  5963 *** Document preparation ***
  5964 
  5965 * formal comments (text blocks etc.) in new-style theories may now
  5966 contain antiquotations of thm/prop/term/typ/text to be presented
  5967 according to latex print mode; concrete syntax is like this:
  5968 @{term[show_types] "f(x) = a + x"};
  5969 
  5970 * isatool mkdir provides easy setup of Isabelle session directories,
  5971 including proper document sources;
  5972 
  5973 * generated LaTeX sources are now deleted after successful run
  5974 (isatool document -c); may retain a copy somewhere else via -D option
  5975 of isatool usedir;
  5976 
  5977 * isatool usedir -D now lets isatool latex -o sty update the Isabelle
  5978 style files, achieving self-contained LaTeX sources and simplifying
  5979 LaTeX debugging;
  5980 
  5981 * old-style theories now produce (crude) LaTeX output as well;
  5982 
  5983 * browser info session directories are now self-contained (may be put
  5984 on WWW server seperately); improved graphs of nested sessions; removed
  5985 graph for 'all sessions';
  5986 
  5987 * several improvements in isabelle style files; \isabellestyle{it}
  5988 produces fake math mode output; \isamarkupheader is now \section by
  5989 default; see lib/texinputs/isabelle.sty etc.;
  5990 
  5991 
  5992 *** Isar ***
  5993 
  5994 * Isar/Pure: local results and corresponding term bindings are now
  5995 subject to Hindley-Milner polymorphism (similar to ML); this
  5996 accommodates incremental type-inference very nicely;
  5997 
  5998 * Isar/Pure: new derived language element 'obtain' supports
  5999 generalized existence reasoning;
  6000 
  6001 * Isar/Pure: new calculational elements 'moreover' and 'ultimately'
  6002 support accumulation of results, without applying any rules yet;
  6003 useful to collect intermediate results without explicit name
  6004 references, and for use with transitivity rules with more than 2
  6005 premises;
  6006 
  6007 * Isar/Pure: scalable support for case-analysis type proofs: new
  6008 'case' language element refers to local contexts symbolically, as
  6009 produced by certain proof methods; internally, case names are attached
  6010 to theorems as "tags";
  6011 
  6012 * Isar/Pure: theory command 'hide' removes declarations from
  6013 class/type/const name spaces;
  6014 
  6015 * Isar/Pure: theory command 'defs' supports option "(overloaded)" to
  6016 indicate potential overloading;
  6017 
  6018 * Isar/Pure: changed syntax of local blocks from {{ }} to { };
  6019 
  6020 * Isar/Pure: syntax of sorts made 'inner', i.e. have to write
  6021 "{a,b,c}" instead of {a,b,c};
  6022 
  6023 * Isar/Pure now provides its own version of intro/elim/dest
  6024 attributes; useful for building new logics, but beware of confusion
  6025 with the version in Provers/classical;
  6026 
  6027 * Isar/Pure: the local context of (non-atomic) goals is provided via
  6028 case name 'antecedent';
  6029 
  6030 * Isar/Pure: removed obsolete 'transfer' attribute (transfer of thms
  6031 to the current context is now done automatically);
  6032 
  6033 * Isar/Pure: theory command 'method_setup' provides a simple interface
  6034 for definining proof methods in ML;
  6035 
  6036 * Isar/Provers: intro/elim/dest attributes changed; renamed
  6037 intro/intro!/intro!! flags to intro!/intro/intro? (INCOMPATIBILITY, in
  6038 most cases, one should have to change intro!! to intro? only);
  6039 replaced "delrule" by "rule del";
  6040 
  6041 * Isar/Provers: new 'hypsubst' method, plain 'subst' method and
  6042 'symmetric' attribute (the latter supercedes [RS sym]);
  6043 
  6044 * Isar/Provers: splitter support (via 'split' attribute and 'simp'
  6045 method modifier); 'simp' method: 'only:' modifier removes loopers as
  6046 well (including splits);
  6047 
  6048 * Isar/Provers: Simplifier and Classical methods now support all kind
  6049 of modifiers used in the past, including 'cong', 'iff', etc.
  6050 
  6051 * Isar/Provers: added 'fastsimp' and 'clarsimp' methods (combination
  6052 of Simplifier and Classical reasoner);
  6053 
  6054 * Isar/HOL: new proof method 'cases' and improved version of 'induct'
  6055 now support named cases; major packages (inductive, datatype, primrec,
  6056 recdef) support case names and properly name parameters;
  6057 
  6058 * Isar/HOL: new transitivity rules for substitution in inequalities --
  6059 monotonicity conditions are extracted to be proven at end of
  6060 calculations;
  6061 
  6062 * Isar/HOL: removed 'case_split' thm binding, should use 'cases' proof
  6063 method anyway;
  6064 
  6065 * Isar/HOL: removed old expand_if = split_if; theorems if_splits =
  6066 split_if split_if_asm; datatype package provides theorems foo.splits =
  6067 foo.split foo.split_asm for each datatype;
  6068 
  6069 * Isar/HOL: tuned inductive package, rename "intrs" to "intros"
  6070 (potential INCOMPATIBILITY), emulation of mk_cases feature for proof
  6071 scripts: new 'inductive_cases' command and 'ind_cases' method; (Note:
  6072 use "(cases (simplified))" method in proper proof texts);
  6073 
  6074 * Isar/HOL: added global 'arith_split' attribute for 'arith' method;
  6075 
  6076 * Isar: names of theorems etc. may be natural numbers as well;
  6077 
  6078 * Isar: 'pr' command: optional arguments for goals_limit and
  6079 ProofContext.prems_limit; no longer prints theory contexts, but only
  6080 proof states;
  6081 
  6082 * Isar: diagnostic commands 'pr', 'thm', 'prop', 'term', 'typ' admit
  6083 additional print modes to be specified; e.g. "pr(latex)" will print
  6084 proof state according to the Isabelle LaTeX style;
  6085 
  6086 * Isar: improved support for emulating tactic scripts, including proof
  6087 methods 'rule_tac' etc., 'cut_tac', 'thin_tac', 'subgoal_tac',
  6088 'rename_tac', 'rotate_tac', 'tactic', and 'case_tac' / 'induct_tac'
  6089 (for HOL datatypes);
  6090 
  6091 * Isar: simplified (more robust) goal selection of proof methods: 1st
  6092 goal, all goals, or explicit goal specifier (tactic emulation); thus
  6093 'proof method scripts' have to be in depth-first order;
  6094 
  6095 * Isar: tuned 'let' syntax: replaced 'as' keyword by 'and';
  6096 
  6097 * Isar: removed 'help' command, which hasn't been too helpful anyway;
  6098 should instead use individual commands for printing items
  6099 (print_commands, print_methods etc.);
  6100 
  6101 * Isar: added 'nothing' --- the empty list of theorems;
  6102 
  6103 
  6104 *** HOL ***
  6105 
  6106 * HOL/MicroJava: formalization of a fragment of Java, together with a
  6107 corresponding virtual machine and a specification of its bytecode
  6108 verifier and a lightweight bytecode verifier, including proofs of
  6109 type-safety; by Gerwin Klein, Tobias Nipkow, David von Oheimb, and
  6110 Cornelia Pusch (see also the homepage of project Bali at
  6111 http://isabelle.in.tum.de/Bali/);
  6112 
  6113 * HOL/Algebra: new theory of rings and univariate polynomials, by
  6114 Clemens Ballarin;
  6115 
  6116 * HOL/NumberTheory: fundamental Theorem of Arithmetic, Chinese
  6117 Remainder Theorem, Fermat/Euler Theorem, Wilson's Theorem, by Thomas M
  6118 Rasmussen;
  6119 
  6120 * HOL/Lattice: fundamental concepts of lattice theory and order
  6121 structures, including duals, properties of bounds versus algebraic
  6122 laws, lattice operations versus set-theoretic ones, the Knaster-Tarski
  6123 Theorem for complete lattices etc.; may also serve as a demonstration
  6124 for abstract algebraic reasoning using axiomatic type classes, and
  6125 mathematics-style proof in Isabelle/Isar; by Markus Wenzel;
  6126 
  6127 * HOL/Prolog: a (bare-bones) implementation of Lambda-Prolog, by David
  6128 von Oheimb;
  6129 
  6130 * HOL/IMPP: extension of IMP with local variables and mutually
  6131 recursive procedures, by David von Oheimb;
  6132 
  6133 * HOL/Lambda: converted into new-style theory and document;
  6134 
  6135 * HOL/ex/Multiquote: example of multiple nested quotations and
  6136 anti-quotations -- basically a generalized version of de-Bruijn
  6137 representation; very useful in avoiding lifting of operations;
  6138 
  6139 * HOL/record: added general record equality rule to simpset; fixed
  6140 select-update simplification procedure to handle extended records as
  6141 well; admit "r" as field name;
  6142 
  6143 * HOL: 0 is now overloaded over the new sort "zero", allowing its use with
  6144 other numeric types and also as the identity of groups, rings, etc.;
  6145 
  6146 * HOL: new axclass plus_ac0 for addition with the AC-laws and 0 as identity.
  6147 Types nat and int belong to this axclass;
  6148 
  6149 * HOL: greatly improved simplification involving numerals of type nat, int, real:
  6150    (i + #8 + j) = Suc k simplifies to  #7 + (i + j) = k
  6151    i*j + k + j*#3*i     simplifies to  #4*(i*j) + k
  6152   two terms #m*u and #n*u are replaced by #(m+n)*u
  6153     (where #m, #n and u can implicitly be 1; this is simproc combine_numerals)
  6154   and the term/formula #m*u+x ~~ #n*u+y simplifies simplifies to #(m-n)+x ~~ y
  6155     or x ~~ #(n-m)+y, where ~~ is one of = < <= or - (simproc cancel_numerals);
  6156 
  6157 * HOL: meson_tac is available (previously in ex/meson.ML); it is a
  6158 powerful prover for predicate logic but knows nothing of clasets; see
  6159 ex/mesontest.ML and ex/mesontest2.ML for example applications;
  6160 
  6161 * HOL: new version of "case_tac" subsumes both boolean case split and
  6162 "exhaust_tac" on datatypes; INCOMPATIBILITY: exhaust_tac no longer
  6163 exists, may define val exhaust_tac = case_tac for ad-hoc portability;
  6164 
  6165 * HOL: simplification no longer dives into case-expressions: only the
  6166 selector expression is simplified, but not the remaining arms; to
  6167 enable full simplification of case-expressions for datatype t, you may
  6168 remove t.weak_case_cong from the simpset, either globally (Delcongs
  6169 [thm"t.weak_case_cong"];) or locally (delcongs [...]).
  6170 
  6171 * HOL/recdef: the recursion equations generated by 'recdef' for
  6172 function 'f' are now called f.simps instead of f.rules; if all
  6173 termination conditions are proved automatically, these simplification
  6174 rules are added to the simpset, as in primrec; rules may be named
  6175 individually as well, resulting in a separate list of theorems for
  6176 each equation;
  6177 
  6178 * HOL/While is a new theory that provides a while-combinator. It
  6179 permits the definition of tail-recursive functions without the
  6180 provision of a termination measure. The latter is necessary once the
  6181 invariant proof rule for while is applied.
  6182 
  6183 * HOL: new (overloaded) notation for the set of elements below/above
  6184 some element: {..u}, {..u(}, {l..}, {)l..}. See theory SetInterval.
  6185 
  6186 * HOL: theorems impI, allI, ballI bound as "strip";
  6187 
  6188 * HOL: new tactic induct_thm_tac: thm -> string -> int -> tactic
  6189 induct_tac th "x1 ... xn" expects th to have a conclusion of the form
  6190 P v1 ... vn and abbreviates res_inst_tac [("v1","x1"),...,("vn","xn")] th;
  6191 
  6192 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  6193 
  6194 * HOL: theory Sexp now in HOL/Induct examples (it used to be part of
  6195 main HOL, but was unused);
  6196 
  6197 * HOL: fewer consts declared as global (e.g. have to refer to
  6198 "Lfp.lfp" instead of "lfp" internally; affects ML packages only);
  6199 
  6200 * HOL: tuned AST representation of nested pairs, avoiding bogus output
  6201 in case of overlap with user translations (e.g. judgements over
  6202 tuples); (note that the underlying logical represenation is still
  6203 bogus);
  6204 
  6205 
  6206 *** ZF ***
  6207 
  6208 * ZF: simplification automatically cancels common terms in arithmetic
  6209 expressions over nat and int;
  6210 
  6211 * ZF: new treatment of nat to minimize type-checking: all operators
  6212 coerce their operands to a natural number using the function natify,
  6213 making the algebraic laws unconditional;
  6214 
  6215 * ZF: as above, for int: operators coerce their operands to an integer
  6216 using the function intify;
  6217 
  6218 * ZF: the integer library now contains many of the usual laws for the
  6219 orderings, including $<=, and monotonicity laws for $+ and $*;
  6220 
  6221 * ZF: new example ZF/ex/NatSum to demonstrate integer arithmetic
  6222 simplification;
  6223 
  6224 * FOL and ZF: AddIffs now available, giving theorems of the form P<->Q
  6225 to the simplifier and classical reasoner simultaneously;
  6226 
  6227 
  6228 *** General ***
  6229 
  6230 * Provers: blast_tac now handles actual object-logic rules as
  6231 assumptions; note that auto_tac uses blast_tac internally as well;
  6232 
  6233 * Provers: new functions rulify/rulify_no_asm: thm -> thm for turning
  6234 outer -->/All/Ball into ==>/!!; qed_spec_mp now uses rulify_no_asm;
<