NEWS
author hoelzl
Mon Aug 23 19:35:57 2010 +0200 (2010-08-23)
changeset 38656 d5d342611edb
parent 38642 8fa437809c67
child 38708 8915e3ce8655
permissions -rw-r--r--
Rewrite the Probability theory.

Introduced pinfreal as real numbers with infinity.
Use pinfreal as value for measures.
Introduces Lebesgue Measure based on the integral in Multivariate Analysis.
Proved Radon Nikodym for arbitrary sigma finite measure spaces.
     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 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
    39 
    40 * Theory SetsAndFunctions has been split into Function_Algebras and Set_Algebras;
    41 canonical names for instance definitions for functions; various improvements.
    42 INCOMPATIBILITY.
    43 
    44 * Records: logical foundation type for records do not carry a '_type' suffix
    45 any longer.  INCOMPATIBILITY.
    46 
    47 * Code generation for records: more idiomatic representation of record types.
    48 Warning: records are not covered by ancient SML code generation any longer.
    49 INCOMPATIBILITY.  In cases of need, a suitable rep_datatype declaration
    50 helps to succeed then:
    51 
    52   record 'a foo = ...
    53   ...
    54   rep_datatype foo_ext ...
    55 
    56 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
    57 INCOMPATIBILITY.
    58 
    59 * Quickcheck in locales considers interpretations of that locale for
    60 counter example search.
    61 
    62 * Theory Library/Monad_Syntax provides do-syntax for monad types.  Syntax
    63 in Library/State_Monad has been changed to avoid ambiguities.
    64 INCOMPATIBILITY.
    65 
    66 * Code generator: export_code without explicit file declaration prints
    67 to standard output.  INCOMPATIBILITY.
    68 
    69 * Abolished symbol type names:  "prod" and "sum" replace "*" and "+"
    70 respectively.  INCOMPATIBILITY.
    71 
    72 * Constant "split" has been merged with constant "prod_case";  names
    73 of ML functions, facts etc. involving split have been retained so far,
    74 though.  INCOMPATIBILITY.
    75 
    76 * Dropped old infix syntax "mem" for List.member;  use "in set"
    77 instead.  INCOMPATIBILITY.
    78 
    79 * Refactoring of code-generation specific operations in List.thy
    80 
    81   constants
    82     null ~> List.null
    83 
    84   facts
    85     mem_iff ~> member_def
    86     null_empty ~> null_def
    87 
    88 INCOMPATIBILITY.  Note that these were not suppossed to be used
    89 regularly unless for striking reasons;  their main purpose was code
    90 generation.
    91 
    92 * Some previously unqualified names have been qualified:
    93 
    94   types
    95     bool ~> HOL.bool
    96     nat ~> Nat.nat
    97 
    98   constants
    99     Trueprop ~> HOL.Trueprop
   100     True ~> HOL.True
   101     False ~> HOL.False
   102     Not ~> HOL.Not
   103     The ~> HOL.The
   104     All ~> HOL.All
   105     Ex ~> HOL.Ex
   106     Ex1 ~> HOL.Ex1
   107     Let ~> HOL.Let
   108     If ~> HOL.If
   109     Ball ~> Set.Ball
   110     Bex ~> Set.Bex
   111     Suc ~> Nat.Suc
   112     Pair ~> Product_Type.Pair
   113     fst ~> Product_Type.fst
   114     snd ~> Product_Type.snd
   115     curry ~> Product_Type.curry
   116     op : ~> Set.member
   117     Collect ~> Set.Collect
   118 
   119 INCOMPATIBILITY.
   120 
   121 * Removed simplifier congruence rule of "prod_case", as has for long
   122 been the case with "split".  INCOMPATIBILITY.
   123 
   124 * Datatype package: theorems generated for executable equality
   125 (class eq) carry proper names and are treated as default code
   126 equations.
   127 
   128 * List.thy: use various operations from the Haskell prelude when
   129 generating Haskell code.
   130 
   131 * code_simp.ML and method code_simp: simplification with rules determined
   132 by code generator.
   133 
   134 * code generator: do not print function definitions for case
   135 combinators any longer.
   136 
   137 * Multivariate Analysis: Introduced a type class for euclidean space. Most
   138 theorems are now stated in terms of euclidean spaces instead of finite
   139 cartesian products.
   140 
   141   types
   142     real ^ 'n ~>  'a::real_vector
   143               ~>  'a::euclidean_space
   144               ~>  'a::ordered_euclidean_space
   145         (depends on your needs)
   146 
   147   constants
   148      _ $ _        ~> _ $$ _
   149      \<chi> x. _  ~> \<chi>\<chi> x. _
   150      CARD('n)     ~> DIM('a)
   151 
   152 Also note that the indices are now natural numbers and not from some finite
   153 type. Finite cartesian products of euclidean spaces, products of euclidean
   154 spaces the real and complex numbers are instantiated to be euclidean_spaces.
   155 
   156 INCOMPATIBILITY.
   157 
   158 * Probability: Introduced pinfreal as real numbers with infinity. Use pinfreal
   159 as value for measures. Introduces Lebesgue Measure based on the integral in
   160 Multivariate Analysis. Proved Radon Nikodym for arbitrary sigma finite measure
   161 spaces.
   162 
   163  INCOMPATIBILITY.
   164 
   165 * Inductive package: offers new command "inductive_simps" to automatically
   166 derive instantiated and simplified equations for inductive predicates,
   167 similar to inductive_cases.
   168 
   169 
   170 *** FOL ***
   171 
   172 * All constant names are now qualified.  INCOMPATIBILITY.
   173 
   174 
   175 *** ZF ***
   176 
   177 * All constant names are now qualified.  INCOMPATIBILITY.
   178 
   179 
   180 *** ML ***
   181 
   182 * ML antiquotations @{theory} and @{theory_ref} refer to named
   183 theories from the ancestry of the current context, not any accidental
   184 theory loader state as before.  Potential INCOMPATIBILITY, subtle
   185 change in semantics.
   186 
   187 
   188 *** System ***
   189 
   190 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   191 
   192 
   193 
   194 New in Isabelle2009-2 (June 2010)
   195 ---------------------------------
   196 
   197 *** General ***
   198 
   199 * Authentic syntax for *all* logical entities (type classes, type
   200 constructors, term constants): provides simple and robust
   201 correspondence between formal entities and concrete syntax.  Within
   202 the parse tree / AST representations, "constants" are decorated by
   203 their category (class, type, const) and spelled out explicitly with
   204 their full internal name.
   205 
   206 Substantial INCOMPATIBILITY concerning low-level syntax declarations
   207 and translations (translation rules and translation functions in ML).
   208 Some hints on upgrading:
   209 
   210   - Many existing uses of 'syntax' and 'translations' can be replaced
   211     by more modern 'type_notation', 'notation' and 'abbreviation',
   212     which are independent of this issue.
   213 
   214   - 'translations' require markup within the AST; the term syntax
   215     provides the following special forms:
   216 
   217       CONST c   -- produces syntax version of constant c from context
   218       XCONST c  -- literally c, checked as constant from context
   219       c         -- literally c, if declared by 'syntax'
   220 
   221     Plain identifiers are treated as AST variables -- occasionally the
   222     system indicates accidental variables via the error "rhs contains
   223     extra variables".
   224 
   225     Type classes and type constructors are marked according to their
   226     concrete syntax.  Some old translations rules need to be written
   227     for the "type" category, using type constructor application
   228     instead of pseudo-term application of the default category
   229     "logic".
   230 
   231   - 'parse_translation' etc. in ML may use the following
   232     antiquotations:
   233 
   234       @{class_syntax c}   -- type class c within parse tree / AST
   235       @{term_syntax c}    -- type constructor c within parse tree / AST
   236       @{const_syntax c}   -- ML version of "CONST c" above
   237       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
   238 
   239   - Literal types within 'typed_print_translations', i.e. those *not*
   240     represented as pseudo-terms are represented verbatim.  Use @{class
   241     c} or @{type_name c} here instead of the above syntax
   242     antiquotations.
   243 
   244 Note that old non-authentic syntax was based on unqualified base
   245 names, so all of the above "constant" names would coincide.  Recall
   246 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
   247 diagnose syntax problems.
   248 
   249 * Type constructors admit general mixfix syntax, not just infix.
   250 
   251 * Concrete syntax may be attached to local entities without a proof
   252 body, too.  This works via regular mixfix annotations for 'fix',
   253 'def', 'obtain' etc. or via the explicit 'write' command, which is
   254 similar to the 'notation' command in theory specifications.
   255 
   256 * Discontinued unnamed infix syntax (legacy feature for many years) --
   257 need to specify constant name and syntax separately.  Internal ML
   258 datatype constructors have been renamed from InfixName to Infix etc.
   259 Minor INCOMPATIBILITY.
   260 
   261 * Schematic theorem statements need to be explicitly markup as such,
   262 via commands 'schematic_lemma', 'schematic_theorem',
   263 'schematic_corollary'.  Thus the relevance of the proof is made
   264 syntactically clear, which impacts performance in a parallel or
   265 asynchronous interactive environment.  Minor INCOMPATIBILITY.
   266 
   267 * Use of cumulative prems via "!" in some proof methods has been
   268 discontinued (old legacy feature).
   269 
   270 * References 'trace_simp' and 'debug_simp' have been replaced by
   271 configuration options stored in the context. Enabling tracing (the
   272 case of debugging is similar) in proofs works via
   273 
   274   using [[trace_simp = true]]
   275 
   276 Tracing is then active for all invocations of the simplifier in
   277 subsequent goal refinement steps. Tracing may also still be enabled or
   278 disabled via the ProofGeneral settings menu.
   279 
   280 * Separate commands 'hide_class', 'hide_type', 'hide_const',
   281 'hide_fact' replace the former 'hide' KIND command.  Minor
   282 INCOMPATIBILITY.
   283 
   284 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
   285 more efficient than combinations with -q1 or -q2.
   286 
   287 
   288 *** Pure ***
   289 
   290 * Proofterms record type-class reasoning explicitly, using the
   291 "unconstrain" operation internally.  This eliminates all sort
   292 constraints from a theorem and proof, introducing explicit
   293 OFCLASS-premises.  On the proof term level, this operation is
   294 automatically applied at theorem boundaries, such that closed proofs
   295 are always free of sort constraints.  INCOMPATIBILITY for tools that
   296 inspect proof terms.
   297 
   298 * Local theory specifications may depend on extra type variables that
   299 are not present in the result type -- arguments TYPE('a) :: 'a itself
   300 are added internally.  For example:
   301 
   302   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
   303 
   304 * Predicates of locales introduced by classes carry a mandatory
   305 "class" prefix.  INCOMPATIBILITY.
   306 
   307 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
   308 
   309 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
   310 'class' instead.
   311 
   312 * Command 'code_reflect' allows to incorporate generated ML code into
   313 runtime environment; replaces immature code_datatype antiquotation.
   314 INCOMPATIBILITY.
   315 
   316 * Code generator: simple concept for abstract datatypes obeying
   317 invariants.
   318 
   319 * Code generator: details of internal data cache have no impact on the
   320 user space functionality any longer.
   321 
   322 * Methods "unfold_locales" and "intro_locales" ignore non-locale
   323 subgoals.  This is more appropriate for interpretations with 'where'.
   324 INCOMPATIBILITY.
   325 
   326 * Command 'example_proof' opens an empty proof body.  This allows to
   327 experiment with Isar, without producing any persistent result.
   328 
   329 * Commands 'type_notation' and 'no_type_notation' declare type syntax
   330 within a local theory context, with explicit checking of the
   331 constructors involved (in contrast to the raw 'syntax' versions).
   332 
   333 * Commands 'types' and 'typedecl' now work within a local theory
   334 context -- without introducing dependencies on parameters or
   335 assumptions, which is not possible in Isabelle/Pure.
   336 
   337 * Command 'defaultsort' has been renamed to 'default_sort', it works
   338 within a local theory context.  Minor INCOMPATIBILITY.
   339 
   340 
   341 *** HOL ***
   342 
   343 * Command 'typedef' now works within a local theory context -- without
   344 introducing dependencies on parameters or assumptions, which is not
   345 possible in Isabelle/Pure/HOL.  Note that the logical environment may
   346 contain multiple interpretations of local typedefs (with different
   347 non-emptiness proofs), even in a global theory context.
   348 
   349 * New package for quotient types.  Commands 'quotient_type' and
   350 'quotient_definition' may be used for defining types and constants by
   351 quotient constructions.  An example is the type of integers created by
   352 quotienting pairs of natural numbers:
   353 
   354   fun
   355     intrel :: "(nat * nat) => (nat * nat) => bool"
   356   where
   357     "intrel (x, y) (u, v) = (x + v = u + y)"
   358 
   359   quotient_type int = "nat * nat" / intrel
   360     by (auto simp add: equivp_def expand_fun_eq)
   361 
   362   quotient_definition
   363     "0::int" is "(0::nat, 0::nat)"
   364 
   365 The method "lifting" can be used to lift of theorems from the
   366 underlying "raw" type to the quotient type.  The example
   367 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
   368 construction and provides a reasoning infrastructure for finite sets.
   369 
   370 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
   371 clash with new theory Quotient in Main HOL.
   372 
   373 * Moved the SMT binding into the main HOL session, eliminating
   374 separate HOL-SMT session.
   375 
   376 * List membership infix mem operation is only an input abbreviation.
   377 INCOMPATIBILITY.
   378 
   379 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
   380 for future developements; former Library/Word.thy is still present in
   381 the AFP entry RSAPPS.
   382 
   383 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
   384 longer shadowed.  INCOMPATIBILITY.
   385 
   386 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
   387 INCOMPATIBILITY.
   388 
   389 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
   390 INCOMPATIBILITY.
   391 
   392 * Dropped normalizing_semiring etc; use the facts in semiring classes
   393 instead.  INCOMPATIBILITY.
   394 
   395 * Dropped several real-specific versions of lemmas about floor and
   396 ceiling; use the generic lemmas from theory "Archimedean_Field"
   397 instead.  INCOMPATIBILITY.
   398 
   399   floor_number_of_eq         ~> floor_number_of
   400   le_floor_eq_number_of      ~> number_of_le_floor
   401   le_floor_eq_zero           ~> zero_le_floor
   402   le_floor_eq_one            ~> one_le_floor
   403   floor_less_eq_number_of    ~> floor_less_number_of
   404   floor_less_eq_zero         ~> floor_less_zero
   405   floor_less_eq_one          ~> floor_less_one
   406   less_floor_eq_number_of    ~> number_of_less_floor
   407   less_floor_eq_zero         ~> zero_less_floor
   408   less_floor_eq_one          ~> one_less_floor
   409   floor_le_eq_number_of      ~> floor_le_number_of
   410   floor_le_eq_zero           ~> floor_le_zero
   411   floor_le_eq_one            ~> floor_le_one
   412   floor_subtract_number_of   ~> floor_diff_number_of
   413   floor_subtract_one         ~> floor_diff_one
   414   ceiling_number_of_eq       ~> ceiling_number_of
   415   ceiling_le_eq_number_of    ~> ceiling_le_number_of
   416   ceiling_le_zero_eq         ~> ceiling_le_zero
   417   ceiling_le_eq_one          ~> ceiling_le_one
   418   less_ceiling_eq_number_of  ~> number_of_less_ceiling
   419   less_ceiling_eq_zero       ~> zero_less_ceiling
   420   less_ceiling_eq_one        ~> one_less_ceiling
   421   ceiling_less_eq_number_of  ~> ceiling_less_number_of
   422   ceiling_less_eq_zero       ~> ceiling_less_zero
   423   ceiling_less_eq_one        ~> ceiling_less_one
   424   le_ceiling_eq_number_of    ~> number_of_le_ceiling
   425   le_ceiling_eq_zero         ~> zero_le_ceiling
   426   le_ceiling_eq_one          ~> one_le_ceiling
   427   ceiling_subtract_number_of ~> ceiling_diff_number_of
   428   ceiling_subtract_one       ~> ceiling_diff_one
   429 
   430 * Theory "Finite_Set": various folding_XXX locales facilitate the
   431 application of the various fold combinators on finite sets.
   432 
   433 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
   434 provides abstract red-black tree type which is backed by "RBT_Impl" as
   435 implementation.  INCOMPATIBILTY.
   436 
   437 * Theory Library/Coinductive_List has been removed -- superseded by
   438 AFP/thys/Coinductive.
   439 
   440 * Theory PReal, including the type "preal" and related operations, has
   441 been removed.  INCOMPATIBILITY.
   442 
   443 * Real: new development using Cauchy Sequences.
   444 
   445 * Split off theory "Big_Operators" containing setsum, setprod,
   446 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
   447 
   448 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
   449 "Int" etc.  INCOMPATIBILITY.
   450 
   451 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
   452 
   453 * New set of rules "ac_simps" provides combined assoc / commute
   454 rewrites for all interpretations of the appropriate generic locales.
   455 
   456 * Renamed theory "OrderedGroup" to "Groups" and split theory
   457 "Ring_and_Field" into theories "Rings" and "Fields"; for more
   458 appropriate and more consistent names suitable for name prefixes
   459 within the HOL theories.  INCOMPATIBILITY.
   460 
   461 * Some generic constants have been put to appropriate theories:
   462   - less_eq, less: Orderings
   463   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
   464   - inverse, divide: Rings
   465 INCOMPATIBILITY.
   466 
   467 * More consistent naming of type classes involving orderings (and
   468 lattices):
   469 
   470     lower_semilattice                   ~> semilattice_inf
   471     upper_semilattice                   ~> semilattice_sup
   472 
   473     dense_linear_order                  ~> dense_linorder
   474 
   475     pordered_ab_group_add               ~> ordered_ab_group_add
   476     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
   477     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
   478     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
   479     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
   480     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
   481     pordered_cancel_semiring            ~> ordered_cancel_semiring
   482     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
   483     pordered_comm_ring                  ~> ordered_comm_ring
   484     pordered_comm_semiring              ~> ordered_comm_semiring
   485     pordered_ring                       ~> ordered_ring
   486     pordered_ring_abs                   ~> ordered_ring_abs
   487     pordered_semiring                   ~> ordered_semiring
   488 
   489     ordered_ab_group_add                ~> linordered_ab_group_add
   490     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
   491     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
   492     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
   493     ordered_field                       ~> linordered_field
   494     ordered_field_no_lb                 ~> linordered_field_no_lb
   495     ordered_field_no_ub                 ~> linordered_field_no_ub
   496     ordered_field_dense_linear_order    ~> dense_linordered_field
   497     ordered_idom                        ~> linordered_idom
   498     ordered_ring                        ~> linordered_ring
   499     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
   500     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
   501     ordered_ring_strict                 ~> linordered_ring_strict
   502     ordered_semidom                     ~> linordered_semidom
   503     ordered_semiring                    ~> linordered_semiring
   504     ordered_semiring_1                  ~> linordered_semiring_1
   505     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
   506     ordered_semiring_strict             ~> linordered_semiring_strict
   507 
   508   The following slightly odd type classes have been moved to a
   509   separate theory Library/Lattice_Algebras:
   510 
   511     lordered_ab_group_add               ~> lattice_ab_group_add
   512     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
   513     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
   514     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
   515     lordered_ring                       ~> lattice_ring
   516 
   517 INCOMPATIBILITY.
   518 
   519 * Refined field classes:
   520   - classes division_ring_inverse_zero, field_inverse_zero,
   521     linordered_field_inverse_zero include rule inverse 0 = 0 --
   522     subsumes former division_by_zero class;
   523   - numerous lemmas have been ported from field to division_ring.
   524 INCOMPATIBILITY.
   525 
   526 * Refined algebra theorem collections:
   527   - dropped theorem group group_simps, use algebra_simps instead;
   528   - dropped theorem group ring_simps, use field_simps instead;
   529   - proper theorem collection field_simps subsumes former theorem
   530     groups field_eq_simps and field_simps;
   531   - dropped lemma eq_minus_self_iff which is a duplicate for
   532     equal_neg_zero.
   533 INCOMPATIBILITY.
   534 
   535 * Theory Finite_Set and List: some lemmas have been generalized from
   536 sets to lattices:
   537 
   538   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
   539   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
   540   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
   541   union_Union_fold_union        ~> sup_Sup_fold_sup
   542   Inter_fold_inter              ~> Inf_fold_inf
   543   Union_fold_union              ~> Sup_fold_sup
   544   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
   545   union_UNION_fold_union        ~> sup_SUPR_fold_sup
   546   INTER_fold_inter              ~> INFI_fold_inf
   547   UNION_fold_union              ~> SUPR_fold_sup
   548 
   549 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
   550 replaced by the more convenient lemmas Inf_empty and Sup_empty.
   551 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
   552 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
   553 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
   554 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
   555 
   556 * Reorganized theory Multiset: swapped notation of pointwise and
   557 multiset order:
   558 
   559   - pointwise ordering is instance of class order with standard syntax
   560     <= and <;
   561   - multiset ordering has syntax <=# and <#; partial order properties
   562     are provided by means of interpretation with prefix
   563     multiset_order;
   564   - less duplication, less historical organization of sections,
   565     conversion from associations lists to multisets, rudimentary code
   566     generation;
   567   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
   568     if needed.
   569 
   570 Renamed:
   571 
   572   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
   573   multi_count_ext  ~>  multiset_ext
   574   diff_union_inverse2  ~>  diff_union_cancelR
   575 
   576 INCOMPATIBILITY.
   577 
   578 * Theory Permutation: replaced local "remove" by List.remove1.
   579 
   580 * Code generation: ML and OCaml code is decorated with signatures.
   581 
   582 * Theory List: added transpose.
   583 
   584 * Library/Nat_Bijection.thy is a collection of bijective functions
   585 between nat and other types, which supersedes the older libraries
   586 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
   587 
   588   Constants:
   589   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
   590   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
   591   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
   592   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
   593   Countable.pair_encode           ~> prod_encode
   594   NatIso.prod2nat                 ~> prod_encode
   595   NatIso.nat2prod                 ~> prod_decode
   596   NatIso.sum2nat                  ~> sum_encode
   597   NatIso.nat2sum                  ~> sum_decode
   598   NatIso.list2nat                 ~> list_encode
   599   NatIso.nat2list                 ~> list_decode
   600   NatIso.set2nat                  ~> set_encode
   601   NatIso.nat2set                  ~> set_decode
   602 
   603   Lemmas:
   604   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
   605   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
   606   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
   607   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
   608   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
   609   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
   610   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
   611   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
   612   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
   613   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
   614   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
   615   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
   616   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
   617 
   618 * Sledgehammer:
   619   - Renamed ATP commands:
   620     atp_info     ~> sledgehammer running_atps
   621     atp_kill     ~> sledgehammer kill_atps
   622     atp_messages ~> sledgehammer messages
   623     atp_minimize ~> sledgehammer minimize
   624     print_atps   ~> sledgehammer available_atps
   625     INCOMPATIBILITY.
   626   - Added user's manual ("isabelle doc sledgehammer").
   627   - Added option syntax and "sledgehammer_params" to customize
   628     Sledgehammer's behavior.  See the manual for details.
   629   - Modified the Isar proof reconstruction code so that it produces
   630     direct proofs rather than proofs by contradiction.  (This feature
   631     is still experimental.)
   632   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
   633     full-typed mode.
   634   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
   635 
   636 * Nitpick:
   637   - Added and implemented "binary_ints" and "bits" options.
   638   - Added "std" option and implemented support for nonstandard models.
   639   - Added and implemented "finitize" option to improve the precision
   640     of infinite datatypes based on a monotonicity analysis.
   641   - Added support for quotient types.
   642   - Added support for "specification" and "ax_specification"
   643     constructs.
   644   - Added support for local definitions (for "function" and
   645     "termination" proofs).
   646   - Added support for term postprocessors.
   647   - Optimized "Multiset.multiset" and "FinFun.finfun".
   648   - Improved efficiency of "destroy_constrs" optimization.
   649   - Fixed soundness bugs related to "destroy_constrs" optimization and
   650     record getters.
   651   - Fixed soundness bug related to higher-order constructors.
   652   - Fixed soundness bug when "full_descrs" is enabled.
   653   - Improved precision of set constructs.
   654   - Added "atoms" option.
   655   - Added cache to speed up repeated Kodkod invocations on the same
   656     problems.
   657   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
   658     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
   659     "SAT4J_Light".  INCOMPATIBILITY.
   660   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
   661     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
   662   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
   663 
   664 * Method "induct" now takes instantiations of the form t, where t is not
   665   a variable, as a shorthand for "x == t", where x is a fresh variable.
   666   If this is not intended, t has to be enclosed in parentheses.
   667   By default, the equalities generated by definitional instantiations
   668   are pre-simplified, which may cause parameters of inductive cases
   669   to disappear, or may even delete some of the inductive cases.
   670   Use "induct (no_simp)" instead of "induct" to restore the old
   671   behaviour. The (no_simp) option is also understood by the "cases"
   672   and "nominal_induct" methods, which now perform pre-simplification, too.
   673   INCOMPATIBILITY.
   674 
   675 
   676 *** HOLCF ***
   677 
   678 * Variable names in lemmas generated by the domain package have
   679 changed; the naming scheme is now consistent with the HOL datatype
   680 package.  Some proof scripts may be affected, INCOMPATIBILITY.
   681 
   682 * The domain package no longer defines the function "foo_copy" for
   683 recursive domain "foo".  The reach lemma is now stated directly in
   684 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
   685 be reformulated in terms of "foo_take", INCOMPATIBILITY.
   686 
   687 * Most definedness lemmas generated by the domain package (previously
   688 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
   689 like "foo$x = UU <-> x = UU", which works better as a simp rule.
   690 Proofs that used definedness lemmas as intro rules may break,
   691 potential INCOMPATIBILITY.
   692 
   693 * Induction and casedist rules generated by the domain package now
   694 declare proper case_names (one called "bottom", and one named for each
   695 constructor).  INCOMPATIBILITY.
   696 
   697 * For mutually-recursive domains, separate "reach" and "take_lemma"
   698 rules are generated for each domain, INCOMPATIBILITY.
   699 
   700   foo_bar.reach       ~> foo.reach  bar.reach
   701   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
   702 
   703 * Some lemmas generated by the domain package have been renamed for
   704 consistency with the datatype package, INCOMPATIBILITY.
   705 
   706   foo.ind        ~> foo.induct
   707   foo.finite_ind ~> foo.finite_induct
   708   foo.coind      ~> foo.coinduct
   709   foo.casedist   ~> foo.exhaust
   710   foo.exhaust    ~> foo.nchotomy
   711 
   712 * For consistency with other definition packages, the fixrec package
   713 now generates qualified theorem names, INCOMPATIBILITY.
   714 
   715   foo_simps  ~> foo.simps
   716   foo_unfold ~> foo.unfold
   717   foo_induct ~> foo.induct
   718 
   719 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
   720 method and internal fixrec proofs now use the default simpset instead.
   721 INCOMPATIBILITY.
   722 
   723 * The "contlub" predicate has been removed.  Proof scripts should use
   724 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
   725 
   726 * The "admw" predicate has been removed, INCOMPATIBILITY.
   727 
   728 * The constants cpair, cfst, and csnd have been removed in favor of
   729 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
   730 
   731 
   732 *** ML ***
   733 
   734 * Antiquotations for basic formal entities:
   735 
   736     @{class NAME}         -- type class
   737     @{class_syntax NAME}  -- syntax representation of the above
   738 
   739     @{type_name NAME}     -- logical type
   740     @{type_abbrev NAME}   -- type abbreviation
   741     @{nonterminal NAME}   -- type of concrete syntactic category
   742     @{type_syntax NAME}   -- syntax representation of any of the above
   743 
   744     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
   745     @{const_abbrev NAME}  -- abbreviated constant
   746     @{const_syntax NAME}  -- syntax representation of any of the above
   747 
   748 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
   749 syntax constant (cf. 'syntax' command).
   750 
   751 * Antiquotation @{make_string} inlines a function to print arbitrary
   752 values similar to the ML toplevel.  The result is compiler dependent
   753 and may fall back on "?" in certain situations.
   754 
   755 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
   756 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
   757 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
   758 not work with the asynchronous Isar document model.
   759 
   760 * Configuration options now admit dynamic default values, depending on
   761 the context or even global references.
   762 
   763 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
   764 uses an efficient external library if available (for Poly/ML).
   765 
   766 * Renamed some important ML structures, while keeping the old names
   767 for some time as aliases within the structure Legacy:
   768 
   769   OuterKeyword  ~>  Keyword
   770   OuterLex      ~>  Token
   771   OuterParse    ~>  Parse
   772   OuterSyntax   ~>  Outer_Syntax
   773   PrintMode     ~>  Print_Mode
   774   SpecParse     ~>  Parse_Spec
   775   ThyInfo       ~>  Thy_Info
   776   ThyLoad       ~>  Thy_Load
   777   ThyOutput     ~>  Thy_Output
   778   TypeInfer     ~>  Type_Infer
   779 
   780 Note that "open Legacy" simplifies porting of sources, but forgetting
   781 to remove it again will complicate porting again in the future.
   782 
   783 * Most operations that refer to a global context are named
   784 accordingly, e.g. Simplifier.global_context or
   785 ProofContext.init_global.  There are some situations where a global
   786 context actually works, but under normal circumstances one needs to
   787 pass the proper local context through the code!
   788 
   789 * Discontinued old TheoryDataFun with its copy/init operation -- data
   790 needs to be pure.  Functor Theory_Data_PP retains the traditional
   791 Pretty.pp argument to merge, which is absent in the standard
   792 Theory_Data version.
   793 
   794 * Sorts.certify_sort and derived "cert" operations for types and terms
   795 no longer minimize sorts.  Thus certification at the boundary of the
   796 inference kernel becomes invariant under addition of class relations,
   797 which is an important monotonicity principle.  Sorts are now minimized
   798 in the syntax layer only, at the boundary between the end-user and the
   799 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
   800 explicitly in rare situations.
   801 
   802 * Renamed old-style Drule.standard to Drule.export_without_context, to
   803 emphasize that this is in no way a standard operation.
   804 INCOMPATIBILITY.
   805 
   806 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
   807 usual for resolution.  Rare INCOMPATIBILITY.
   808 
   809 * Renamed varify/unvarify operations to varify_global/unvarify_global
   810 to emphasize that these only work in a global situation (which is
   811 quite rare).
   812 
   813 * Curried take and drop in library.ML; negative length is interpreted
   814 as infinity (as in chop).  Subtle INCOMPATIBILITY.
   815 
   816 * Proof terms: type substitutions on proof constants now use canonical
   817 order of type variables.  INCOMPATIBILITY for tools working with proof
   818 terms.
   819 
   820 * Raw axioms/defs may no longer carry sort constraints, and raw defs
   821 may no longer carry premises.  User-level specifications are
   822 transformed accordingly by Thm.add_axiom/add_def.
   823 
   824 
   825 *** System ***
   826 
   827 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
   828 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
   829 proof terms are enabled unconditionally in the new HOL-Proofs image.
   830 
   831 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
   832 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
   833 respectively.
   834 
   835 * Old lib/scripts/polyml-platform is superseded by the
   836 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
   837 variant, even on a 64 bit machine.  The following example setting
   838 prefers 64 bit if available:
   839 
   840   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
   841 
   842 * The preliminary Isabelle/jEdit application demonstrates the emerging
   843 Isabelle/Scala layer for advanced prover interaction and integration.
   844 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
   845 component.
   846 
   847 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
   848 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
   849 similar to the default assignment of the document preparation system
   850 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
   851 provides some operations for direct access to the font without asking
   852 the user for manual installation.
   853 
   854 
   855 
   856 New in Isabelle2009-1 (December 2009)
   857 -------------------------------------
   858 
   859 *** General ***
   860 
   861 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
   862 one backslash should be used, even in ML sources.
   863 
   864 
   865 *** Pure ***
   866 
   867 * Locale interpretation propagates mixins along the locale hierarchy.
   868 The currently only available mixins are the equations used to map
   869 local definitions to terms of the target domain of an interpretation.
   870 
   871 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
   872 loc" to print all interpretations of locale "loc" in the theory.
   873 Interpretations in proofs are not shown.
   874 
   875 * Thoroughly revised locales tutorial.  New section on conditional
   876 interpretation.
   877 
   878 * On instantiation of classes, remaining undefined class parameters
   879 are formally declared.  INCOMPATIBILITY.
   880 
   881 
   882 *** Document preparation ***
   883 
   884 * New generalized style concept for printing terms: @{foo (style) ...}
   885 instead of @{foo_style style ...}  (old form is still retained for
   886 backward compatibility).  Styles can be also applied for
   887 antiquotations prop, term_type and typeof.
   888 
   889 
   890 *** HOL ***
   891 
   892 * New proof method "smt" for a combination of first-order logic with
   893 equality, linear and nonlinear (natural/integer/real) arithmetic, and
   894 fixed-size bitvectors; there is also basic support for higher-order
   895 features (esp. lambda abstractions).  It is an incomplete decision
   896 procedure based on external SMT solvers using the oracle mechanism;
   897 for the SMT solver Z3, this method is proof-producing.  Certificates
   898 are provided to avoid calling the external solvers solely for
   899 re-checking proofs.  Due to a remote SMT service there is no need for
   900 installing SMT solvers locally.  See src/HOL/SMT.
   901 
   902 * New commands to load and prove verification conditions generated by
   903 the Boogie program verifier or derived systems (e.g. the Verifying C
   904 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
   905 
   906 * New counterexample generator tool 'nitpick' based on the Kodkod
   907 relational model finder.  See src/HOL/Tools/Nitpick and
   908 src/HOL/Nitpick_Examples.
   909 
   910 * New commands 'code_pred' and 'values' to invoke the predicate
   911 compiler and to enumerate values of inductive predicates.
   912 
   913 * A tabled implementation of the reflexive transitive closure.
   914 
   915 * New implementation of quickcheck uses generic code generator;
   916 default generators are provided for all suitable HOL types, records
   917 and datatypes.  Old quickcheck can be re-activated importing theory
   918 Library/SML_Quickcheck.
   919 
   920 * New testing tool Mirabelle for automated proof tools.  Applies
   921 several tools and tactics like sledgehammer, metis, or quickcheck, to
   922 every proof step in a theory.  To be used in batch mode via the
   923 "mirabelle" utility.
   924 
   925 * New proof method "sos" (sum of squares) for nonlinear real
   926 arithmetic (originally due to John Harison). It requires theory
   927 Library/Sum_Of_Squares.  It is not a complete decision procedure but
   928 works well in practice on quantifier-free real arithmetic with +, -,
   929 *, ^, =, <= and <, i.e. boolean combinations of equalities and
   930 inequalities between polynomials.  It makes use of external
   931 semidefinite programming solvers.  Method "sos" generates a
   932 certificate that can be pasted into the proof thus avoiding the need
   933 to call an external tool every time the proof is checked.  See
   934 src/HOL/Library/Sum_Of_Squares.
   935 
   936 * New method "linarith" invokes existing linear arithmetic decision
   937 procedure only.
   938 
   939 * New command 'atp_minimal' reduces result produced by Sledgehammer.
   940 
   941 * New Sledgehammer option "Full Types" in Proof General settings menu.
   942 Causes full type information to be output to the ATPs.  This slows
   943 ATPs down considerably but eliminates a source of unsound "proofs"
   944 that fail later.
   945 
   946 * New method "metisFT": A version of metis that uses full type
   947 information in order to avoid failures of proof reconstruction.
   948 
   949 * New evaluator "approximate" approximates an real valued term using
   950 the same method as the approximation method.
   951 
   952 * Method "approximate" now supports arithmetic expressions as
   953 boundaries of intervals and implements interval splitting and Taylor
   954 series expansion.
   955 
   956 * ML antiquotation @{code_datatype} inserts definition of a datatype
   957 generated by the code generator; e.g. see src/HOL/Predicate.thy.
   958 
   959 * New theory SupInf of the supremum and infimum operators for sets of
   960 reals.
   961 
   962 * New theory Probability, which contains a development of measure
   963 theory, eventually leading to Lebesgue integration and probability.
   964 
   965 * Extended Multivariate Analysis to include derivation and Brouwer's
   966 fixpoint theorem.
   967 
   968 * Reorganization of number theory, INCOMPATIBILITY:
   969   - new number theory development for nat and int, in theories Divides
   970     and GCD as well as in new session Number_Theory
   971   - some constants and facts now suffixed with _nat and _int
   972     accordingly
   973   - former session NumberTheory now named Old_Number_Theory, including
   974     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
   975   - moved theory Pocklington from src/HOL/Library to
   976     src/HOL/Old_Number_Theory
   977 
   978 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
   979 lcm of finite and infinite sets. It is shown that they form a complete
   980 lattice.
   981 
   982 * Class semiring_div requires superclass no_zero_divisors and proof of
   983 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
   984 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
   985 generalized to class semiring_div, subsuming former theorems
   986 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
   987 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
   988 INCOMPATIBILITY.
   989 
   990 * Refinements to lattice classes and sets:
   991   - less default intro/elim rules in locale variant, more default
   992     intro/elim rules in class variant: more uniformity
   993   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
   994     le_inf_iff
   995   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
   996     sup_aci)
   997   - renamed ACI to inf_sup_aci
   998   - new class "boolean_algebra"
   999   - class "complete_lattice" moved to separate theory
  1000     "Complete_Lattice"; corresponding constants (and abbreviations)
  1001     renamed and with authentic syntax:
  1002     Set.Inf ~>    Complete_Lattice.Inf
  1003     Set.Sup ~>    Complete_Lattice.Sup
  1004     Set.INFI ~>   Complete_Lattice.INFI
  1005     Set.SUPR ~>   Complete_Lattice.SUPR
  1006     Set.Inter ~>  Complete_Lattice.Inter
  1007     Set.Union ~>  Complete_Lattice.Union
  1008     Set.INTER ~>  Complete_Lattice.INTER
  1009     Set.UNION ~>  Complete_Lattice.UNION
  1010   - authentic syntax for
  1011     Set.Pow
  1012     Set.image
  1013   - mere abbreviations:
  1014     Set.empty               (for bot)
  1015     Set.UNIV                (for top)
  1016     Set.inter               (for inf, formerly Set.Int)
  1017     Set.union               (for sup, formerly Set.Un)
  1018     Complete_Lattice.Inter  (for Inf)
  1019     Complete_Lattice.Union  (for Sup)
  1020     Complete_Lattice.INTER  (for INFI)
  1021     Complete_Lattice.UNION  (for SUPR)
  1022   - object-logic definitions as far as appropriate
  1023 
  1024 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1025 Un_subset_iff are explicitly deleted as default simp rules; then also
  1026 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1027 deleted to achieve the desired effect.
  1028 
  1029 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1030 rules by default any longer; the same applies to min_max.inf_absorb1
  1031 etc.  INCOMPATIBILITY.
  1032 
  1033 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1034 pred_set_conv by default.  INCOMPATIBILITY.
  1035 
  1036 * Power operations on relations and functions are now one dedicated
  1037 constant "compow" with infix syntax "^^".  Power operation on
  1038 multiplicative monoids retains syntax "^" and is now defined generic
  1039 in class power.  INCOMPATIBILITY.
  1040 
  1041 * Relation composition "R O S" now has a more standard argument order:
  1042 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1043 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1044 break, since the O_assoc rule was not rewritten like this.  Fix using
  1045 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1046 
  1047 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1048 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1049 INCOMPATIBILITY.
  1050 
  1051 * Most rules produced by inductive and datatype package have mandatory
  1052 prefixes.  INCOMPATIBILITY.
  1053 
  1054 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1055 the attribute of the same name.  Each of the theorems in the list
  1056 DERIV_intros assumes composition with an additional function and
  1057 matches a variable to the derivative, which has to be solved by the
  1058 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1059 of most elementary terms.  Former Maclauren.DERIV_tac and
  1060 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1061 INCOMPATIBILITY.
  1062 
  1063 * Code generator attributes follow the usual underscore convention:
  1064     code_unfold     replaces    code unfold
  1065     code_post       replaces    code post
  1066     etc.
  1067   INCOMPATIBILITY.
  1068 
  1069 * Renamed methods:
  1070     sizechange -> size_change
  1071     induct_scheme -> induction_schema
  1072   INCOMPATIBILITY.
  1073 
  1074 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1075 INCOMPATIBILITY, use "undefined" directly.
  1076 
  1077 * Renamed theorems:
  1078     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1079     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1080     Suc_plus1 -> Suc_eq_plus1
  1081     *anti_sym -> *antisym*
  1082     vector_less_eq_def -> vector_le_def
  1083   INCOMPATIBILITY.
  1084 
  1085 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1086 INCOMPATIBILITY.
  1087 
  1088 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1089 INCOMPATIBILITY.
  1090 
  1091 
  1092 *** HOLCF ***
  1093 
  1094 * Theory Representable defines a class "rep" of domains that are
  1095 representable (via an ep-pair) in the universal domain type "udom".
  1096 Instances are provided for all type constructors defined in HOLCF.
  1097 
  1098 * The 'new_domain' command is a purely definitional version of the
  1099 domain package, for representable domains.  Syntax is identical to the
  1100 old domain package.  The 'new_domain' package also supports indirect
  1101 recursion using previously-defined type constructors.  See
  1102 src/HOLCF/ex/New_Domain.thy for examples.
  1103 
  1104 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1105 on the left-hand side of an equation, and then performs
  1106 simplification.  Rewriting is done using rules declared with the
  1107 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1108 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1109 
  1110 * The pattern-match compiler in 'fixrec' can now handle constructors
  1111 with HOL function types.  Pattern-match combinators for the Pair
  1112 constructor are pre-configured.
  1113 
  1114 * The 'fixrec' package now produces better fixed-point induction rules
  1115 for mutually-recursive definitions:  Induction rules have conclusions
  1116 of the form "P foo bar" instead of "P <foo, bar>".
  1117 
  1118 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1119 been renamed to "below".  The name "below" now replaces "less" in many
  1120 theorem names.  (Legacy theorem names using "less" are still supported
  1121 as well.)
  1122 
  1123 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1124 patterns can be used to generate strictness rules, or to make
  1125 functions more strict (much like the bang-patterns supported by the
  1126 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1127 examples.
  1128 
  1129 
  1130 *** ML ***
  1131 
  1132 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1133 errors and run-time exceptions, including detailed source positions.
  1134 
  1135 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1136 identified entries, with some additional information such as source
  1137 position, logical grouping etc.
  1138 
  1139 * Theory and context data is now introduced by the simplified and
  1140 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1141 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1142 copy operation) is still available for some time.
  1143 
  1144 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1145 provides a high-level programming interface to synchronized state
  1146 variables with atomic update.  This works via pure function
  1147 application within a critical section -- its runtime should be as
  1148 short as possible; beware of deadlocks if critical code is nested,
  1149 either directly or indirectly via other synchronized variables!
  1150 
  1151 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1152 wraps raw ML references, explicitly indicating their non-thread-safe
  1153 behaviour.  The Isar toplevel keeps this structure open, to
  1154 accommodate Proof General as well as quick and dirty interactive
  1155 experiments with references.
  1156 
  1157 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1158 parallel tactical reasoning.
  1159 
  1160 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1161 are similar to SUBPROOF, but are slightly more flexible: only the
  1162 specified parts of the subgoal are imported into the context, and the
  1163 body tactic may introduce new subgoals and schematic variables.
  1164 
  1165 * Old tactical METAHYPS, which does not observe the proof context, has
  1166 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1167 or Subgoal.FOCUS etc.
  1168 
  1169 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1170 functors have their own ML name space there is no point to mark them
  1171 separately.)  Minor INCOMPATIBILITY.
  1172 
  1173 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1174 
  1175 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1176 INCOMPATIBILITY.
  1177 
  1178 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1179 mode, which avoids critical setmp.
  1180 
  1181 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1182 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1183 Attrib/Method.setup introduced in Isabelle2009.
  1184 
  1185 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1186 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1187 last resort.  INCOMPATIBILITY.
  1188 
  1189 * Display.pretty_thm now requires a proper context (cf. former
  1190 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1191 or even Display.pretty_thm_without_context as last resort.
  1192 INCOMPATIBILITY.
  1193 
  1194 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1195 Syntax.pretty_typ/term directly, preferably with proper context
  1196 instead of global theory.
  1197 
  1198 
  1199 *** System ***
  1200 
  1201 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1202 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1203 usedir option -q.
  1204 
  1205 * Support for additional "Isabelle components" via etc/components, see
  1206 also the system manual.
  1207 
  1208 * The isabelle makeall tool now operates on all components with
  1209 IsaMakefile, not just hardwired "logics".
  1210 
  1211 * Removed "compress" option from isabelle-process and isabelle usedir;
  1212 this is always enabled.
  1213 
  1214 * Discontinued support for Poly/ML 4.x versions.
  1215 
  1216 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  1217 on a given logic image.  This requires the lighttpd webserver and is
  1218 currently supported on Linux only.
  1219 
  1220 
  1221 
  1222 New in Isabelle2009 (April 2009)
  1223 --------------------------------
  1224 
  1225 *** General ***
  1226 
  1227 * Simplified main Isabelle executables, with less surprises on
  1228 case-insensitive file-systems (such as Mac OS).
  1229 
  1230   - The main Isabelle tool wrapper is now called "isabelle" instead of
  1231     "isatool."
  1232 
  1233   - The former "isabelle" alias for "isabelle-process" has been
  1234     removed (should rarely occur to regular users).
  1235 
  1236   - The former "isabelle-interface" and its alias "Isabelle" have been
  1237     removed (interfaces are now regular Isabelle tools).
  1238 
  1239 Within scripts and make files, the Isabelle environment variables
  1240 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  1241 respectively.  (The latter are still available as legacy feature.)
  1242 
  1243 The old isabelle-interface wrapper could react in confusing ways if
  1244 the interface was uninstalled or changed otherwise.  Individual
  1245 interface tool configuration is now more explicit, see also the
  1246 Isabelle system manual.  In particular, Proof General is now available
  1247 via "isabelle emacs".
  1248 
  1249 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  1250 purge installed copies of Isabelle executables and re-run "isabelle
  1251 install -p ...", or use symlinks.
  1252 
  1253 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  1254 old ~/isabelle, which was slightly non-standard and apt to cause
  1255 surprises on case-insensitive file-systems (such as Mac OS).
  1256 
  1257 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  1258 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  1259 care is required when using older releases of Isabelle.  Note that
  1260 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  1261 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  1262 
  1263 * Proofs of fully specified statements are run in parallel on
  1264 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  1265 a regular 4-core machine, if the initial heap space is made reasonably
  1266 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  1267 
  1268 * The main reference manuals ("isar-ref", "implementation", and
  1269 "system") have been updated and extended.  Formally checked references
  1270 as hyperlinks are now available uniformly.
  1271 
  1272 
  1273 *** Pure ***
  1274 
  1275 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  1276 respects.  The most important changes are listed below.  See the
  1277 Tutorial on Locales ("locales" manual) for details.
  1278 
  1279 - In locale expressions, instantiation replaces renaming.  Parameters
  1280 must be declared in a for clause.  To aid compatibility with previous
  1281 parameter inheritance, in locale declarations, parameters that are not
  1282 'touched' (instantiation position "_" or omitted) are implicitly added
  1283 with their syntax at the beginning of the for clause.
  1284 
  1285 - Syntax from abbreviations and definitions in locales is available in
  1286 locale expressions and context elements.  The latter is particularly
  1287 useful in locale declarations.
  1288 
  1289 - More flexible mechanisms to qualify names generated by locale
  1290 expressions.  Qualifiers (prefixes) may be specified in locale
  1291 expressions, and can be marked as mandatory (syntax: "name!:") or
  1292 optional (syntax "name?:").  The default depends for plain "name:"
  1293 depends on the situation where a locale expression is used: in
  1294 commands 'locale' and 'sublocale' prefixes are optional, in
  1295 'interpretation' and 'interpret' prefixes are mandatory.  The old
  1296 implicit qualifiers derived from the parameter names of a locale are
  1297 no longer generated.
  1298 
  1299 - Command "sublocale l < e" replaces "interpretation l < e".  The
  1300 instantiation clause in "interpretation" and "interpret" (square
  1301 brackets) is no longer available.  Use locale expressions.
  1302 
  1303 - When converting proof scripts, mandatory qualifiers in
  1304 'interpretation' and 'interpret' should be retained by default, even
  1305 if this is an INCOMPATIBILITY compared to former behavior.  In the
  1306 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  1307 in locale expressions range over a single locale instance only.
  1308 
  1309 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  1310 In existing theorem specifications replace the includes element by the
  1311 respective context elements of the included locale, omitting those
  1312 that are already present in the theorem specification.  Multiple
  1313 assume elements of a locale should be replaced by a single one
  1314 involving the locale predicate.  In the proof body, declarations (most
  1315 notably theorems) may be regained by interpreting the respective
  1316 locales in the proof context as required (command "interpret").
  1317 
  1318 If using "includes" in replacement of a target solely because the
  1319 parameter types in the theorem are not as general as in the target,
  1320 consider declaring a new locale with additional type constraints on
  1321 the parameters (context element "constrains").
  1322 
  1323 - Discontinued "locale (open)".  INCOMPATIBILITY.
  1324 
  1325 - Locale interpretation commands no longer attempt to simplify goal.
  1326 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  1327 methods intro_locales and unfold_locales to clarify.
  1328 
  1329 - Locale interpretation commands no longer accept interpretation
  1330 attributes.  INCOMPATIBILITY.
  1331 
  1332 * Class declaration: so-called "base sort" must not be given in import
  1333 list any longer, but is inferred from the specification.  Particularly
  1334 in HOL, write
  1335 
  1336     class foo = ...
  1337 
  1338 instead of
  1339 
  1340     class foo = type + ...
  1341 
  1342 * Class target: global versions of theorems stemming do not carry a
  1343 parameter prefix any longer.  INCOMPATIBILITY.
  1344 
  1345 * Class 'instance' command no longer accepts attached definitions.
  1346 INCOMPATIBILITY, use proper 'instantiation' target instead.
  1347 
  1348 * Recovered hiding of consts, which was accidentally broken in
  1349 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  1350 makes c inaccessible; consider using ``hide (open) const c'' instead.
  1351 
  1352 * Slightly more coherent Pure syntax, with updated documentation in
  1353 isar-ref manual.  Removed locales meta_term_syntax and
  1354 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  1355 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  1356 directly in regular applications.
  1357 
  1358 * There is a new syntactic category "float_const" for signed decimal
  1359 fractions (e.g. 123.45 or -123.45).
  1360 
  1361 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  1362 interface with 'setup' command instead.
  1363 
  1364 * Command 'local_setup' is similar to 'setup', but operates on a local
  1365 theory context.
  1366 
  1367 * The 'axiomatization' command now only works within a global theory
  1368 context.  INCOMPATIBILITY.
  1369 
  1370 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  1371 hypotheses.  Sorts required in the course of reasoning need to be
  1372 covered by the constraints in the initial statement, completed by the
  1373 type instance information of the background theory.  Non-trivial sort
  1374 hypotheses, which rarely occur in practice, may be specified via
  1375 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  1376 
  1377   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  1378 
  1379 The result contains an implicit sort hypotheses as before --
  1380 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  1381 normalization.
  1382 
  1383 * Generalized Isar history, with support for linear undo, direct state
  1384 addressing etc.
  1385 
  1386 * Changed defaults for unify configuration options:
  1387 
  1388   unify_trace_bound = 50 (formerly 25)
  1389   unify_search_bound = 60 (formerly 30)
  1390 
  1391 * Different bookkeeping for code equations (INCOMPATIBILITY):
  1392 
  1393   a) On theory merge, the last set of code equations for a particular
  1394      constant is taken (in accordance with the policy applied by other
  1395      parts of the code generator framework).
  1396 
  1397   b) Code equations stemming from explicit declarations (e.g. code
  1398      attribute) gain priority over default code equations stemming
  1399      from definition, primrec, fun etc.
  1400 
  1401 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  1402 
  1403 * Unified theorem tables for both code generators.  Thus [code
  1404 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  1405 
  1406 * Command 'find_consts' searches for constants based on type and name
  1407 patterns, e.g.
  1408 
  1409     find_consts "_ => bool"
  1410 
  1411 By default, matching is against subtypes, but it may be restricted to
  1412 the whole type.  Searching by name is possible.  Multiple queries are
  1413 conjunctive and queries may be negated by prefixing them with a
  1414 hyphen:
  1415 
  1416     find_consts strict: "_ => bool" name: "Int" -"int => int"
  1417 
  1418 * New 'find_theorems' criterion "solves" matches theorems that
  1419 directly solve the current goal (modulo higher-order unification).
  1420 
  1421 * Auto solve feature for main theorem statements: whenever a new goal
  1422 is stated, "find_theorems solves" is called; any theorems that could
  1423 solve the lemma directly are listed as part of the goal state.
  1424 Cf. associated options in Proof General Isabelle settings menu,
  1425 enabled by default, with reasonable timeout for pathological cases of
  1426 higher-order unification.
  1427 
  1428 
  1429 *** Document preparation ***
  1430 
  1431 * Antiquotation @{lemma} now imitates a regular terminal proof,
  1432 demanding keyword 'by' and supporting the full method expression
  1433 syntax just like the Isar command 'by'.
  1434 
  1435 
  1436 *** HOL ***
  1437 
  1438 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  1439 points Main and Complex_Main remain as before.
  1440 
  1441 * Logic image HOL-Plain provides a minimal HOL with the most important
  1442 tools available (inductive, datatype, primrec, ...).  This facilitates
  1443 experimentation and tool development.  Note that user applications
  1444 (and library theories) should never refer to anything below theory
  1445 Main, as before.
  1446 
  1447 * Logic image HOL-Main stops at theory Main, and thus facilitates
  1448 experimentation due to shorter build times.
  1449 
  1450 * Logic image HOL-NSA contains theories of nonstandard analysis which
  1451 were previously part of former HOL-Complex.  Entry point Hyperreal
  1452 remains valid, but theories formerly using Complex_Main should now use
  1453 new entry point Hypercomplex.
  1454 
  1455 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  1456 Posix processes.  Avoids potentially expensive forking of the ML
  1457 process.  New thread-based implementation also works on non-Unix
  1458 platforms (Cygwin).  Provers are no longer hardwired, but defined
  1459 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  1460 commands are covered in the isar-ref manual.
  1461 
  1462 * Wrapper scripts for remote SystemOnTPTP service allows to use
  1463 sledgehammer without local ATP installation (Vampire etc.). Other
  1464 provers may be included via suitable ML wrappers, see also
  1465 src/HOL/ATP_Linkup.thy.
  1466 
  1467 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  1468 menu.
  1469 
  1470 * The metis method no longer fails because the theorem is too trivial
  1471 (contains the empty clause).
  1472 
  1473 * The metis method now fails in the usual manner, rather than raising
  1474 an exception, if it determines that it cannot prove the theorem.
  1475 
  1476 * Method "coherent" implements a prover for coherent logic (see also
  1477 src/Tools/coherent.ML).
  1478 
  1479 * Constants "undefined" and "default" replace "arbitrary".  Usually
  1480 "undefined" is the right choice to replace "arbitrary", though
  1481 logically there is no difference.  INCOMPATIBILITY.
  1482 
  1483 * Command "value" now integrates different evaluation mechanisms.  The
  1484 result of the first successful evaluation mechanism is printed.  In
  1485 square brackets a particular named evaluation mechanisms may be
  1486 specified (currently, [SML], [code] or [nbe]).  See further
  1487 src/HOL/ex/Eval_Examples.thy.
  1488 
  1489 * Normalization by evaluation now allows non-leftlinear equations.
  1490 Declare with attribute [code nbe].
  1491 
  1492 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  1493 as the structured Isar versions "cases" and "induct", cf. the
  1494 corresponding "cases" and "induct" attributes.  Mutual induction rules
  1495 are now presented as a list of individual projections
  1496 (e.g. foo_bar.inducts for types foo and bar); the old format with
  1497 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  1498 rare situations a different rule is selected --- notably nested tuple
  1499 elimination instead of former prod.exhaust: use explicit (case_tac t
  1500 rule: prod.exhaust) here.
  1501 
  1502 * Attributes "cases", "induct", "coinduct" support "del" option.
  1503 
  1504 * Removed fact "case_split_thm", which duplicates "case_split".
  1505 
  1506 * The option datatype has been moved to a new theory Option.  Renamed
  1507 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  1508 
  1509 * New predicate "strict_mono" classifies strict functions on partial
  1510 orders.  With strict functions on linear orders, reasoning about
  1511 (in)equalities is facilitated by theorems "strict_mono_eq",
  1512 "strict_mono_less_eq" and "strict_mono_less".
  1513 
  1514 * Some set operations are now proper qualified constants with
  1515 authentic syntax.  INCOMPATIBILITY:
  1516 
  1517     op Int ~>   Set.Int
  1518     op Un ~>    Set.Un
  1519     INTER ~>    Set.INTER
  1520     UNION ~>    Set.UNION
  1521     Inter ~>    Set.Inter
  1522     Union ~>    Set.Union
  1523     {} ~>       Set.empty
  1524     UNIV ~>     Set.UNIV
  1525 
  1526 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  1527 theory Set.
  1528 
  1529 * Auxiliary class "itself" has disappeared -- classes without any
  1530 parameter are treated as expected by the 'class' command.
  1531 
  1532 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  1533 
  1534 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  1535 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  1536 
  1537 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  1538 method "approximation".  It proves formulas on real values by using
  1539 interval arithmetic.  In the formulas are also the transcendental
  1540 functions sin, cos, tan, atan, ln, exp and the constant pi are
  1541 allowed. For examples see
  1542 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  1543 
  1544 * Theory "Reflection" now resides in HOL/Library.
  1545 
  1546 * Entry point to Word library now simply named "Word".
  1547 INCOMPATIBILITY.
  1548 
  1549 * Made source layout more coherent with logical distribution
  1550 structure:
  1551 
  1552     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  1553     src/HOL/Library/Code_Message.thy ~> src/HOL/
  1554     src/HOL/Library/GCD.thy ~> src/HOL/
  1555     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  1556     src/HOL/Library/Parity.thy ~> src/HOL/
  1557     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  1558     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  1559     src/HOL/Real/Lubs.thy ~> src/HOL/
  1560     src/HOL/Real/PReal.thy ~> src/HOL/
  1561     src/HOL/Real/Rational.thy ~> src/HOL/
  1562     src/HOL/Real/RComplete.thy ~> src/HOL/
  1563     src/HOL/Real/RealDef.thy ~> src/HOL/
  1564     src/HOL/Real/RealPow.thy ~> src/HOL/
  1565     src/HOL/Real/Real.thy ~> src/HOL/
  1566     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  1567     src/HOL/Complex/Complex.thy ~> src/HOL/
  1568     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  1569     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  1570     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  1571     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  1572     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  1573     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  1574     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  1575     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  1576     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  1577     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  1578     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  1579     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  1580     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  1581     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  1582     src/HOL/Real/Float ~> src/HOL/Library/
  1583     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  1584     src/HOL/Real/RealVector.thy ~> src/HOL/
  1585 
  1586     src/HOL/arith_data.ML ~> src/HOL/Tools
  1587     src/HOL/hologic.ML ~> src/HOL/Tools
  1588     src/HOL/simpdata.ML ~> src/HOL/Tools
  1589     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  1590     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  1591     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  1592     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  1593     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  1594     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  1595     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  1596 
  1597     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  1598     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  1599     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  1600     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  1601     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  1602     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  1603 
  1604 * If methods "eval" and "evaluation" encounter a structured proof
  1605 state with !!/==>, only the conclusion is evaluated to True (if
  1606 possible), avoiding strange error messages.
  1607 
  1608 * Method "sizechange" automates termination proofs using (a
  1609 modification of) the size-change principle.  Requires SAT solver.  See
  1610 src/HOL/ex/Termination.thy for examples.
  1611 
  1612 * Simplifier: simproc for let expressions now unfolds if bound
  1613 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  1614 
  1615 * Method "arith": Linear arithmetic now ignores all inequalities when
  1616 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  1617 
  1618 * New attribute "arith" for facts that should always be used
  1619 automatically by arithmetic. It is intended to be used locally in
  1620 proofs, e.g.
  1621 
  1622   assumes [arith]: "x > 0"
  1623 
  1624 Global usage is discouraged because of possible performance impact.
  1625 
  1626 * New classes "top" and "bot" with corresponding operations "top" and
  1627 "bot" in theory Orderings; instantiation of class "complete_lattice"
  1628 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  1629 
  1630 * Changed definition lemma "less_fun_def" in order to provide an
  1631 instance for preorders on functions; use lemma "less_le" instead.
  1632 INCOMPATIBILITY.
  1633 
  1634 * Theory Orderings: class "wellorder" moved here, with explicit
  1635 induction rule "less_induct" as assumption.  For instantiation of
  1636 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  1637 INCOMPATIBILITY.
  1638 
  1639 * Theory Orderings: added class "preorder" as superclass of "order".
  1640 INCOMPATIBILITY: Instantiation proofs for order, linorder
  1641 etc. slightly changed.  Some theorems named order_class.* now named
  1642 preorder_class.*.
  1643 
  1644 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  1645 "diag" to "Id_on".
  1646 
  1647 * Theory Finite_Set: added a new fold combinator of type
  1648 
  1649   ('a => 'b => 'b) => 'b => 'a set => 'b
  1650 
  1651 Occasionally this is more convenient than the old fold combinator
  1652 which is now defined in terms of the new one and renamed to
  1653 fold_image.
  1654 
  1655 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  1656 and "ring_simps" have been replaced by "algebra_simps" (which can be
  1657 extended with further lemmas!).  At the moment both still exist but
  1658 the former will disappear at some point.
  1659 
  1660 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  1661 class recpower.  Type-specific simp rules for various recpower types
  1662 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  1663 
  1664 rat_power_0    -> power_0
  1665 rat_power_Suc  -> power_Suc
  1666 realpow_0      -> power_0
  1667 realpow_Suc    -> power_Suc
  1668 complexpow_0   -> power_0
  1669 complexpow_Suc -> power_Suc
  1670 power_poly_0   -> power_0
  1671 power_poly_Suc -> power_Suc
  1672 
  1673 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  1674 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  1675 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  1676 of lemmas from Divides has been generalized from nat to class
  1677 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  1678 renames resulting from duplicate elimination:
  1679 
  1680     dvd_def_mod ~>          dvd_eq_mod_eq_0
  1681     zero_dvd_iff ~>         dvd_0_left_iff
  1682     dvd_0 ~>                dvd_0_right
  1683     DIVISION_BY_ZERO_DIV ~> div_by_0
  1684     DIVISION_BY_ZERO_MOD ~> mod_by_0
  1685     mult_div ~>             div_mult_self2_is_id
  1686     mult_mod ~>             mod_mult_self2_is_0
  1687 
  1688 * Theory IntDiv: removed many lemmas that are instances of class-based
  1689 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  1690 rename old lemmas as follows:
  1691 
  1692 dvd_diff               -> nat_dvd_diff
  1693 dvd_zminus_iff         -> dvd_minus_iff
  1694 mod_add1_eq            -> mod_add_eq
  1695 mod_mult1_eq           -> mod_mult_right_eq
  1696 mod_mult1_eq'          -> mod_mult_left_eq
  1697 mod_mult_distrib_mod   -> mod_mult_eq
  1698 nat_mod_add_left_eq    -> mod_add_left_eq
  1699 nat_mod_add_right_eq   -> mod_add_right_eq
  1700 nat_mod_div_trivial    -> mod_div_trivial
  1701 nat_mod_mod_trivial    -> mod_mod_trivial
  1702 zdiv_zadd_self1        -> div_add_self1
  1703 zdiv_zadd_self2        -> div_add_self2
  1704 zdiv_zmult_self1       -> div_mult_self2_is_id
  1705 zdiv_zmult_self2       -> div_mult_self1_is_id
  1706 zdvd_triv_left         -> dvd_triv_left
  1707 zdvd_triv_right        -> dvd_triv_right
  1708 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  1709 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  1710 zmod_zadd_left_eq      -> mod_add_left_eq
  1711 zmod_zadd_right_eq     -> mod_add_right_eq
  1712 zmod_zadd_self1        -> mod_add_self1
  1713 zmod_zadd_self2        -> mod_add_self2
  1714 zmod_zadd1_eq          -> mod_add_eq
  1715 zmod_zdiff1_eq         -> mod_diff_eq
  1716 zmod_zdvd_zmod         -> mod_mod_cancel
  1717 zmod_zmod_cancel       -> mod_mod_cancel
  1718 zmod_zmult_self1       -> mod_mult_self2_is_0
  1719 zmod_zmult_self2       -> mod_mult_self1_is_0
  1720 zmod_1                 -> mod_by_1
  1721 zdiv_1                 -> div_by_1
  1722 zdvd_abs1              -> abs_dvd_iff
  1723 zdvd_abs2              -> dvd_abs_iff
  1724 zdvd_refl              -> dvd_refl
  1725 zdvd_trans             -> dvd_trans
  1726 zdvd_zadd              -> dvd_add
  1727 zdvd_zdiff             -> dvd_diff
  1728 zdvd_zminus_iff        -> dvd_minus_iff
  1729 zdvd_zminus2_iff       -> minus_dvd_iff
  1730 zdvd_zmultD            -> dvd_mult_right
  1731 zdvd_zmultD2           -> dvd_mult_left
  1732 zdvd_zmult_mono        -> mult_dvd_mono
  1733 zdvd_0_right           -> dvd_0_right
  1734 zdvd_0_left            -> dvd_0_left_iff
  1735 zdvd_1_left            -> one_dvd
  1736 zminus_dvd_iff         -> minus_dvd_iff
  1737 
  1738 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  1739 
  1740 * The real numbers offer decimal input syntax: 12.34 is translated
  1741 into 1234/10^2. This translation is not reversed upon output.
  1742 
  1743 * Theory Library/Polynomial defines an abstract type 'a poly of
  1744 univariate polynomials with coefficients of type 'a.  In addition to
  1745 the standard ring operations, it also supports div and mod.  Code
  1746 generation is also supported, using list-style constructors.
  1747 
  1748 * Theory Library/Inner_Product defines a class of real_inner for real
  1749 inner product spaces, with an overloaded operation inner :: 'a => 'a
  1750 => real.  Class real_inner is a subclass of real_normed_vector from
  1751 theory RealVector.
  1752 
  1753 * Theory Library/Product_Vector provides instances for the product
  1754 type 'a * 'b of several classes from RealVector and Inner_Product.
  1755 Definitions of addition, subtraction, scalar multiplication, norms,
  1756 and inner products are included.
  1757 
  1758 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  1759 addition to the field operations, numerals and case syntax are also
  1760 supported.
  1761 
  1762 * Theory Library/Diagonalize provides constructive version of Cantor's
  1763 first diagonalization argument.
  1764 
  1765 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  1766 zlcm (for int); carried together from various gcd/lcm developements in
  1767 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  1768 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  1769 may recover tupled syntax as follows:
  1770 
  1771     hide (open) const gcd
  1772     abbreviation gcd where
  1773       "gcd == (%(a, b). GCD.gcd a b)"
  1774     notation (output)
  1775       GCD.gcd ("gcd '(_, _')")
  1776 
  1777 The same works for lcm, zgcd, zlcm.
  1778 
  1779 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  1780 instantiations for algebraic structures.  Removed some duplicate
  1781 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  1782 
  1783 * ML antiquotation @{code} takes a constant as argument and generates
  1784 corresponding code in background and inserts name of the corresponding
  1785 resulting ML value/function/datatype constructor binding in place.
  1786 All occurrences of @{code} with a single ML block are generated
  1787 simultaneously.  Provides a generic and safe interface for
  1788 instrumentalizing code generation.  See
  1789 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  1790 In future you ought to refrain from ad-hoc compiling generated SML
  1791 code on the ML toplevel.  Note that (for technical reasons) @{code}
  1792 cannot refer to constants for which user-defined serializations are
  1793 set.  Refer to the corresponding ML counterpart directly in that
  1794 cases.
  1795 
  1796 * Command 'rep_datatype': instead of theorem names the command now
  1797 takes a list of terms denoting the constructors of the type to be
  1798 represented as datatype.  The characteristic theorems have to be
  1799 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  1800 have disappeared in favour of existing ones:
  1801 
  1802     unit_induct                 ~> unit.induct
  1803     prod_induct                 ~> prod.induct
  1804     sum_induct                  ~> sum.induct
  1805     Suc_Suc_eq                  ~> nat.inject
  1806     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  1807 
  1808 
  1809 *** HOL-Algebra ***
  1810 
  1811 * New locales for orders and lattices where the equivalence relation
  1812 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  1813 locales use a record structure with field eq for the equivalence.
  1814 
  1815 * New theory of factorial domains.
  1816 
  1817 * Units_l_inv and Units_r_inv are now simp rules by default.
  1818 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  1819 and/or r_inv will now also require deletion of these lemmas.
  1820 
  1821 * Renamed the following theorems, INCOMPATIBILITY:
  1822 
  1823 UpperD ~> Upper_memD
  1824 LowerD ~> Lower_memD
  1825 least_carrier ~> least_closed
  1826 greatest_carrier ~> greatest_closed
  1827 greatest_Lower_above ~> greatest_Lower_below
  1828 one_zero ~> carrier_one_zero
  1829 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  1830 
  1831 
  1832 *** HOL-Nominal ***
  1833 
  1834 * Nominal datatypes can now contain type-variables.
  1835 
  1836 * Commands 'nominal_inductive' and 'equivariance' work with local
  1837 theory targets.
  1838 
  1839 * Nominal primrec can now works with local theory targets and its
  1840 specification syntax now conforms to the general format as seen in
  1841 'inductive' etc.
  1842 
  1843 * Method "perm_simp" honours the standard simplifier attributes
  1844 (no_asm), (no_asm_use) etc.
  1845 
  1846 * The new predicate #* is defined like freshness, except that on the
  1847 left hand side can be a set or list of atoms.
  1848 
  1849 * Experimental command 'nominal_inductive2' derives strong induction
  1850 principles for inductive definitions.  In contrast to
  1851 'nominal_inductive', which can only deal with a fixed number of
  1852 binders, it can deal with arbitrary expressions standing for sets of
  1853 atoms to be avoided.  The only inductive definition we have at the
  1854 moment that needs this generalisation is the typing rule for Lets in
  1855 the algorithm W:
  1856 
  1857  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  1858  -----------------------------------------------------------------
  1859          Gamma |- Let x be t1 in t2 : T2
  1860 
  1861 In this rule one wants to avoid all the binders that are introduced by
  1862 "close Gamma T1".  We are looking for other examples where this
  1863 feature might be useful.  Please let us know.
  1864 
  1865 
  1866 *** HOLCF ***
  1867 
  1868 * Reimplemented the simplification procedure for proving continuity
  1869 subgoals.  The new simproc is extensible; users can declare additional
  1870 continuity introduction rules with the attribute [cont2cont].
  1871 
  1872 * The continuity simproc now uses a different introduction rule for
  1873 solving continuity subgoals on terms with lambda abstractions.  In
  1874 some rare cases the new simproc may fail to solve subgoals that the
  1875 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  1876 Potential INCOMPATIBILITY.
  1877 
  1878 * Command 'fixrec': specification syntax now conforms to the general
  1879 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  1880 examples.  INCOMPATIBILITY.
  1881 
  1882 
  1883 *** ZF ***
  1884 
  1885 * Proof of Zorn's Lemma for partial orders.
  1886 
  1887 
  1888 *** ML ***
  1889 
  1890 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  1891 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  1892 depends on multithreading, so timouts will not work before Poly/ML
  1893 5.2.1!
  1894 
  1895 * High-level support for concurrent ML programming, see
  1896 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  1897 particularly convenient to organize independent functional
  1898 computations.  The concept of "synchronized variables" provides a
  1899 higher-order interface for components with shared state, avoiding the
  1900 delicate details of mutexes and condition variables.  (Requires
  1901 Poly/ML 5.2.1 or later.)
  1902 
  1903 * ML bindings produced via Isar commands are stored within the Isar
  1904 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  1905 become thread-safe and work with undo as expected (concerning
  1906 top-level bindings, not side-effects on global references).
  1907 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  1908 compiler at runtime; really global bindings need to be given outside a
  1909 theory.  (Requires Poly/ML 5.2 or later.)
  1910 
  1911 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  1912 context.  Top-level ML bindings are stored within the proof context in
  1913 a purely sequential fashion, disregarding the nested proof structure.
  1914 ML bindings introduced by 'ML_prf' are discarded at the end of the
  1915 proof.  (Requires Poly/ML 5.2 or later.)
  1916 
  1917 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  1918 and Method.setup, as well as Isar commands 'attribute_setup' and
  1919 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  1920 existing code accordingly, or use plain 'setup' together with old
  1921 Method.add_method.
  1922 
  1923 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  1924 to 'a -> thm, while results are always tagged with an authentic oracle
  1925 name.  The Isar command 'oracle' is now polymorphic, no argument type
  1926 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  1927 accordingly.  Note that extra performance may be gained by producing
  1928 the cterm carefully, avoiding slow Thm.cterm_of.
  1929 
  1930 * Simplified interface for defining document antiquotations via
  1931 ThyOutput.antiquotation, ThyOutput.output, and optionally
  1932 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  1933 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  1934 examples.
  1935 
  1936 * More systematic treatment of long names, abstract name bindings, and
  1937 name space operations.  Basic operations on qualified names have been
  1938 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  1939 Long_Name.append.  Old type bstring has been mostly replaced by
  1940 abstract type binding (see structure Binding), which supports precise
  1941 qualification by packages and local theory targets, as well as proper
  1942 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  1943 bstring values into Binding.name, or better pass through abstract
  1944 bindings everywhere.  See further src/Pure/General/long_name.ML,
  1945 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  1946 
  1947 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  1948 LocalTheory.note etc.) now refer to the *full* internal name, not the
  1949 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  1950 
  1951 * Disposed old type and term read functions (Sign.read_def_typ,
  1952 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  1953 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  1954 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  1955 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  1956 resort for legacy applications.
  1957 
  1958 * Disposed old declarations, tactics, tactic combinators that refer to
  1959 the simpset or claset of an implicit theory (such as Addsimps,
  1960 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  1961 embedded ML text, or local_simpset_of with a proper context passed as
  1962 explicit runtime argument.
  1963 
  1964 * Rules and tactics that read instantiations (read_instantiate,
  1965 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  1966 context, which is required for parsing and type-checking.  Moreover,
  1967 the variables are specified as plain indexnames, not string encodings
  1968 thereof.  INCOMPATIBILITY.
  1969 
  1970 * Generic Toplevel.add_hook interface allows to analyze the result of
  1971 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  1972 for theorem dependency output of transactions resulting in a new
  1973 theory state.
  1974 
  1975 * ML antiquotations: block-structured compilation context indicated by
  1976 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  1977 
  1978   @{binding name}                         - basic name binding
  1979   @{let ?pat = term}                      - term abbreviation (HO matching)
  1980   @{note name = fact}                     - fact abbreviation
  1981   @{thm fact}                             - singleton fact (with attributes)
  1982   @{thms fact}                            - general fact (with attributes)
  1983   @{lemma prop by method}                 - singleton goal
  1984   @{lemma prop by meth1 meth2}            - singleton goal
  1985   @{lemma prop1 ... propN by method}      - general goal
  1986   @{lemma prop1 ... propN by meth1 meth2} - general goal
  1987   @{lemma (open) ...}                     - open derivation
  1988 
  1989 
  1990 *** System ***
  1991 
  1992 * The Isabelle "emacs" tool provides a specific interface to invoke
  1993 Proof General / Emacs, with more explicit failure if that is not
  1994 installed (the old isabelle-interface script silently falls back on
  1995 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  1996 installation location of the Proof General distribution.
  1997 
  1998 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  1999 the Isabelle process into a JVM/Scala application.  See
  2000 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2001 process wrapper has been discontinued.)
  2002 
  2003 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2004 
  2005 * Various status messages (with exact source position information) are
  2006 emitted, if proper markup print mode is enabled.  This allows
  2007 user-interface components to provide detailed feedback on internal
  2008 prover operations.
  2009 
  2010 
  2011 
  2012 New in Isabelle2008 (June 2008)
  2013 -------------------------------
  2014 
  2015 *** General ***
  2016 
  2017 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2018 and updated, with formally checked references as hyperlinks.
  2019 
  2020 * Theory loader: use_thy (and similar operations) no longer set the
  2021 implicit ML context, which was occasionally hard to predict and in
  2022 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2023 provides a proper context already.
  2024 
  2025 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2026 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2027 'use' within a theory file will do the job.
  2028 
  2029 * Name space merge now observes canonical order, i.e. the second space
  2030 is inserted into the first one, while existing entries in the first
  2031 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2032 swap theory imports.
  2033 
  2034 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2035 INCOMPATIBILITY in identifier syntax etc.
  2036 
  2037 * Outer syntax: string tokens no longer admit escaped white space,
  2038 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2039 white space without escapes.
  2040 
  2041 * Outer syntax: string tokens may contain arbitrary character codes
  2042 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2043 "foo_bar".
  2044 
  2045 
  2046 *** Pure ***
  2047 
  2048 * Context-dependent token translations.  Default setup reverts locally
  2049 fixed variables, and adds hilite markup for undeclared frees.
  2050 
  2051 * Unused theorems can be found using the new command 'unused_thms'.
  2052 There are three ways of invoking it:
  2053 
  2054 (1) unused_thms
  2055      Only finds unused theorems in the current theory.
  2056 
  2057 (2) unused_thms thy_1 ... thy_n -
  2058      Finds unused theorems in the current theory and all of its ancestors,
  2059      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2060 
  2061 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2062      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2063      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2064      their ancestors.
  2065 
  2066 In order to increase the readability of the list produced by
  2067 unused_thms, theorems that have been created by a particular instance
  2068 of a theory command such as 'inductive' or 'function' are considered
  2069 to belong to the same "group", meaning that if at least one theorem in
  2070 this group is used, the other theorems in the same group are no longer
  2071 reported as unused.  Moreover, if all theorems in the group are
  2072 unused, only one theorem in the group is displayed.
  2073 
  2074 Note that proof objects have to be switched on in order for
  2075 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2076 usually the case when using Proof General with the default settings).
  2077 
  2078 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2079 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2080 duplicate fact bindings, or even accidental fact duplications.  Note
  2081 that tools may maintain dynamically scoped facts systematically, using
  2082 PureThy.add_thms_dynamic.
  2083 
  2084 * Command 'hide' now allows to hide from "fact" name space as well.
  2085 
  2086 * Eliminated destructive theorem database, simpset, claset, and
  2087 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2088 update of theories within ML code.
  2089 
  2090 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2091 INCOMPATIBILITY, object-logics depending on former Pure require
  2092 additional setup PureThy.old_appl_syntax_setup; object-logics
  2093 depending on former CPure need to refer to Pure.
  2094 
  2095 * Commands 'use' and 'ML' are now purely functional, operating on
  2096 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2097 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2098 INCOMPATIBILITY.
  2099 
  2100 * Command 'setup': discontinued implicit version with ML reference.
  2101 
  2102 * Instantiation target allows for simultaneous specification of class
  2103 instance operations together with an instantiation proof.
  2104 Type-checking phase allows to refer to class operations uniformly.
  2105 See src/HOL/Complex/Complex.thy for an Isar example and
  2106 src/HOL/Library/Eval.thy for an ML example.
  2107 
  2108 * Indexing of literal facts: be more serious about including only
  2109 facts from the visible specification/proof context, but not the
  2110 background context (locale etc.).  Affects `prop` notation and method
  2111 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2112 situations.
  2113 
  2114 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2115 "(open)" option, which used to expose internal bound variables to the
  2116 proof text.
  2117 
  2118 * Isar statements: removed obsolete case "rule_context".
  2119 INCOMPATIBILITY, better use explicit fixes/assumes.
  2120 
  2121 * Locale proofs: default proof step now includes 'unfold_locales';
  2122 hence 'proof' without argument may be used to unfold locale
  2123 predicates.
  2124 
  2125 
  2126 *** Document preparation ***
  2127 
  2128 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2129 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2130 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2131 spot); renamed link color from "darkblue" to "linkcolor" (default
  2132 value unchanged, can be redefined via \definecolor); no longer sets
  2133 "a4paper" option (unnecessary or even intrusive).
  2134 
  2135 * Antiquotation @{lemma A method} proves proposition A by the given
  2136 method (either a method name or a method name plus (optional) method
  2137 arguments in parentheses) and prints A just like @{prop A}.
  2138 
  2139 
  2140 *** HOL ***
  2141 
  2142 * New primrec package.  Specification syntax conforms in style to
  2143 definition/function/....  No separate induction rule is provided.  The
  2144 "primrec" command distinguishes old-style and new-style specifications
  2145 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2146 When adjusting theories, beware: constants stemming from new-style
  2147 primrec specifications have authentic syntax.
  2148 
  2149 * Metis prover is now an order of magnitude faster, and also works
  2150 with multithreading.
  2151 
  2152 * Metis: the maximum number of clauses that can be produced from a
  2153 theorem is now given by the attribute max_clauses.  Theorems that
  2154 exceed this number are ignored, with a warning printed.
  2155 
  2156 * Sledgehammer no longer produces structured proofs by default. To
  2157 enable, declare [[sledgehammer_full = true]].  Attributes
  2158 reconstruction_modulus, reconstruction_sorts renamed
  2159 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2160 
  2161 * Method "induct_scheme" derives user-specified induction rules
  2162 from well-founded induction and completeness of patterns. This factors
  2163 out some operations that are done internally by the function package
  2164 and makes them available separately.  See
  2165 src/HOL/ex/Induction_Scheme.thy for examples.
  2166 
  2167 * More flexible generation of measure functions for termination
  2168 proofs: Measure functions can be declared by proving a rule of the
  2169 form "is_measure f" and giving it the [measure_function] attribute.
  2170 The "is_measure" predicate is logically meaningless (always true), and
  2171 just guides the heuristic.  To find suitable measure functions, the
  2172 termination prover sets up the goal "is_measure ?f" of the appropriate
  2173 type and generates all solutions by prolog-style backwards proof using
  2174 the declared rules.
  2175 
  2176 This setup also deals with rules like 
  2177 
  2178   "is_measure f ==> is_measure (list_size f)"
  2179 
  2180 which accommodates nested datatypes that recurse through lists.
  2181 Similar rules are predeclared for products and option types.
  2182 
  2183 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2184 
  2185   INCOMPATIBILITIES:
  2186 
  2187   - Definitions of overloaded constants on sets have to be replaced by
  2188     definitions on => and bool.
  2189 
  2190   - Some definitions of overloaded operators on sets can now be proved
  2191     using the definitions of the operators on => and bool.  Therefore,
  2192     the following theorems have been renamed:
  2193 
  2194       subset_def   -> subset_eq
  2195       psubset_def  -> psubset_eq
  2196       set_diff_def -> set_diff_eq
  2197       Compl_def    -> Compl_eq
  2198       Sup_set_def  -> Sup_set_eq
  2199       Inf_set_def  -> Inf_set_eq
  2200       sup_set_def  -> sup_set_eq
  2201       inf_set_def  -> inf_set_eq
  2202 
  2203   - Due to the incompleteness of the HO unification algorithm, some
  2204     rules such as subst may require manual instantiation, if some of
  2205     the unknowns in the rule is a set.
  2206 
  2207   - Higher order unification and forward proofs:
  2208     The proof pattern
  2209 
  2210       have "P (S::'a set)" <...>
  2211       then have "EX S. P S" ..
  2212 
  2213     no longer works (due to the incompleteness of the HO unification
  2214     algorithm) and must be replaced by the pattern
  2215 
  2216       have "EX S. P S"
  2217       proof
  2218         show "P S" <...>
  2219       qed
  2220 
  2221   - Calculational reasoning with subst (or similar rules):
  2222     The proof pattern
  2223 
  2224       have "P (S::'a set)" <...>
  2225       also have "S = T" <...>
  2226       finally have "P T" .
  2227 
  2228     no longer works (for similar reasons as the previous example) and
  2229     must be replaced by something like
  2230 
  2231       have "P (S::'a set)" <...>
  2232       moreover have "S = T" <...>
  2233       ultimately have "P T" by simp
  2234 
  2235   - Tactics or packages written in ML code:
  2236     Code performing pattern matching on types via
  2237 
  2238       Type ("set", [T]) => ...
  2239 
  2240     must be rewritten. Moreover, functions like strip_type or
  2241     binder_types no longer return the right value when applied to a
  2242     type of the form
  2243 
  2244       T1 => ... => Tn => U => bool
  2245 
  2246     rather than
  2247 
  2248       T1 => ... => Tn => U set
  2249 
  2250 * Merged theories Wellfounded_Recursion, Accessible_Part and
  2251 Wellfounded_Relations to theory Wellfounded.
  2252 
  2253 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  2254 
  2255 * Class finite no longer treats UNIV as class parameter.  Use class
  2256 enum from theory Library/Enum instead to achieve a similar effect.
  2257 INCOMPATIBILITY.
  2258 
  2259 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  2260 and "Cons".  INCOMPATIBILITY.
  2261 
  2262 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  2263 Potential INCOMPATIBILITY.
  2264 
  2265 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  2266 injective_fst_snd removed, use split_eta and prod_eqI instead.
  2267 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  2268 
  2269 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  2270 the same name in theory Orderings:
  2271 
  2272   less_trans
  2273   less_linear
  2274   le_imp_less_or_eq
  2275   le_less_trans
  2276   less_le_trans
  2277   less_not_sym
  2278   less_asym
  2279 
  2280 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  2281 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  2282 and different variable names.
  2283 
  2284 * Library/Option_ord.thy: Canonical order on option type.
  2285 
  2286 * Library/RBT.thy: Red-black trees, an efficient implementation of
  2287 finite maps.
  2288 
  2289 * Library/Countable.thy: Type class for countable types.
  2290 
  2291 * Theory Int: The representation of numerals has changed.  The infix
  2292 operator BIT and the bit datatype with constructors B0 and B1 have
  2293 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  2294 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  2295 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  2296 accordingly.
  2297 
  2298 * Theory Nat: definition of <= and < on natural numbers no longer
  2299 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  2300 le_def and less_def have disappeared.  Consider lemmas not_less
  2301 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  2302 
  2303 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  2304 (whose purpose mainly is for various fold_set functionals) have been
  2305 abandoned in favor of the existing algebraic classes
  2306 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  2307 lower_semilattice (resp. upper_semilattice) and linorder.
  2308 INCOMPATIBILITY.
  2309 
  2310 * Theory Transitive_Closure: induct and cases rules now declare proper
  2311 case_names ("base" and "step").  INCOMPATIBILITY.
  2312 
  2313 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  2314 lattices.  The form set-specific version is available as
  2315 Inductive.lfp_ordinal_induct_set.
  2316 
  2317 * Renamed theorems "power.simps" to "power_int.simps".
  2318 INCOMPATIBILITY.
  2319 
  2320 * Class semiring_div provides basic abstract properties of semirings
  2321 with division and modulo operations.  Subsumes former class dvd_mod.
  2322 
  2323 * Merged theories IntDef, Numeral and IntArith into unified theory
  2324 Int.  INCOMPATIBILITY.
  2325 
  2326 * Theory Library/Code_Index: type "index" now represents natural
  2327 numbers rather than integers.  INCOMPATIBILITY.
  2328 
  2329 * New class "uminus" with operation "uminus" (split of from class
  2330 "minus" which now only has operation "minus", binary).
  2331 INCOMPATIBILITY.
  2332 
  2333 * Constants "card", "internal_split", "option_map" now with authentic
  2334 syntax.  INCOMPATIBILITY.
  2335 
  2336 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  2337 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  2338 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  2339 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  2340 Sup_set_def, le_def, less_def, option_map_def now with object
  2341 equality.  INCOMPATIBILITY.
  2342 
  2343 * Records. Removed K_record, and replaced it by pure lambda term
  2344 %x. c. The simplifier setup is now more robust against eta expansion.
  2345 INCOMPATIBILITY: in cases explicitly referring to K_record.
  2346 
  2347 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  2348 
  2349 * Library/ListVector: new theory of arithmetic vector operations.
  2350 
  2351 * Library/Order_Relation: new theory of various orderings as sets of
  2352 pairs.  Defines preorders, partial orders, linear orders and
  2353 well-orders on sets and on types.
  2354 
  2355 
  2356 *** ZF ***
  2357 
  2358 * Renamed some theories to allow to loading both ZF and HOL in the
  2359 same session:
  2360 
  2361   Datatype  -> Datatype_ZF
  2362   Inductive -> Inductive_ZF
  2363   Int       -> Int_ZF
  2364   IntDiv    -> IntDiv_ZF
  2365   Nat       -> Nat_ZF
  2366   List      -> List_ZF
  2367   Main      -> Main_ZF
  2368 
  2369 INCOMPATIBILITY: ZF theories that import individual theories below
  2370 Main might need to be adapted.  Regular theory Main is still
  2371 available, as trivial extension of Main_ZF.
  2372 
  2373 
  2374 *** ML ***
  2375 
  2376 * ML within Isar: antiquotation @{const name} or @{const
  2377 name(typargs)} produces statically-checked Const term.
  2378 
  2379 * Functor NamedThmsFun: data is available to the user as dynamic fact
  2380 (of the same name).  Removed obsolete print command.
  2381 
  2382 * Removed obsolete "use_legacy_bindings" function.
  2383 
  2384 * The ``print mode'' is now a thread-local value derived from a global
  2385 template (the former print_mode reference), thus access becomes
  2386 non-critical.  The global print_mode reference is for session
  2387 management only; user-code should use print_mode_value,
  2388 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  2389 
  2390 * Functions system/system_out provide a robust way to invoke external
  2391 shell commands, with propagation of interrupts (requires Poly/ML
  2392 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  2393 
  2394 
  2395 *** System ***
  2396 
  2397 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  2398 in accordance with Proof General 3.7, which prefers GNU emacs.
  2399 
  2400 * isatool tty runs Isabelle process with plain tty interaction;
  2401 optional line editor may be specified via ISABELLE_LINE_EDITOR
  2402 setting, the default settings attempt to locate "ledit" and "rlwrap".
  2403 
  2404 * isatool browser now works with Cygwin as well, using general
  2405 "javapath" function defined in Isabelle process environment.
  2406 
  2407 * YXML notation provides a simple and efficient alternative to
  2408 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  2409 isatool yxml as described in the Isabelle system manual.
  2410 
  2411 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  2412 provides general wrapper for managing an Isabelle process in a robust
  2413 fashion, with ``cooked'' output from stdin/stderr.
  2414 
  2415 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  2416 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  2417 
  2418 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  2419 way of changing the user's settings is via
  2420 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  2421 script.
  2422 
  2423 * Multithreading.max_threads := 0 refers to the number of actual CPU
  2424 cores of the underlying machine, which is a good starting point for
  2425 optimal performance tuning.  The corresponding usedir option -M allows
  2426 "max" as an alias for "0".  WARNING: does not work on certain versions
  2427 of Mac OS (with Poly/ML 5.1).
  2428 
  2429 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  2430 adverse effect of Isabelle flooding interactive front-ends (notably
  2431 ProofGeneral / XEmacs).
  2432 
  2433 
  2434 
  2435 New in Isabelle2007 (November 2007)
  2436 -----------------------------------
  2437 
  2438 *** General ***
  2439 
  2440 * More uniform information about legacy features, notably a
  2441 warning/error of "Legacy feature: ...", depending on the state of the
  2442 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  2443 legacy features will disappear eventually.
  2444 
  2445 * Theory syntax: the header format ``theory A = B + C:'' has been
  2446 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  2447 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  2448 
  2449 * Theory syntax: the old non-Isar theory file format has been
  2450 discontinued altogether.  Note that ML proof scripts may still be used
  2451 with Isar theories; migration is usually quite simple with the ML
  2452 function use_legacy_bindings.  INCOMPATIBILITY.
  2453 
  2454 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  2455 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  2456 quotes.
  2457 
  2458 * Theory loader: be more serious about observing the static theory
  2459 header specifications (including optional directories), but not the
  2460 accidental file locations of previously successful loads.  The strict
  2461 update policy of former update_thy is now already performed by
  2462 use_thy, so the former has been removed; use_thys updates several
  2463 theories simultaneously, just as 'imports' within a theory header
  2464 specification, but without merging the results.  Potential
  2465 INCOMPATIBILITY: may need to refine theory headers and commands
  2466 ROOT.ML which depend on load order.
  2467 
  2468 * Theory loader: optional support for content-based file
  2469 identification, instead of the traditional scheme of full physical
  2470 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  2471 (cf. the system manual).  The new scheme allows to work with
  2472 non-finished theories in persistent session images, such that source
  2473 files may be moved later on without requiring reloads.
  2474 
  2475 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2476 file (with the same base name as the theory) are considered a legacy
  2477 feature, which will disappear eventually. Even now, the theory loader
  2478 no longer maintains dependencies on such files.
  2479 
  2480 * Syntax: the scope for resolving ambiguities via type-inference is
  2481 now limited to individual terms, instead of whole simultaneous
  2482 specifications as before. This greatly reduces the complexity of the
  2483 syntax module and improves flexibility by separating parsing and
  2484 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  2485 'fixes' etc.) are required in rare situations.
  2486 
  2487 * Syntax: constants introduced by new-style packages ('definition',
  2488 'abbreviation' etc.) are passed through the syntax module in
  2489 ``authentic mode''. This means that associated mixfix annotations
  2490 really stick to such constants, independently of potential name space
  2491 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  2492 trees are represented slightly differently, may need to adapt syntax
  2493 translations accordingly. Use CONST marker in 'translations' and
  2494 @{const_syntax} antiquotation in 'parse_translation' etc.
  2495 
  2496 * Legacy goal package: reduced interface to the bare minimum required
  2497 to keep existing proof scripts running.  Most other user-level
  2498 functions are now part of the OldGoals structure, which is *not* open
  2499 by default (consider isatool expandshort before open OldGoals).
  2500 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  2501 these tend to cause confusion about the actual goal (!) context being
  2502 used here, which is not necessarily the same as the_context().
  2503 
  2504 * Command 'find_theorems': supports "*" wild-card in "name:"
  2505 criterion; "with_dups" option.  Certain ProofGeneral versions might
  2506 support a specific search form (see ProofGeneral/CHANGES).
  2507 
  2508 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  2509 by default, which means that "prems" (and also "fixed variables") are
  2510 suppressed from proof state output.  Note that the ProofGeneral
  2511 settings mechanism allows to change and save options persistently, but
  2512 older versions of Isabelle will fail to start up if a negative prems
  2513 limit is imposed.
  2514 
  2515 * Local theory targets may be specified by non-nested blocks of
  2516 ``context/locale/class ... begin'' followed by ``end''.  The body may
  2517 contain definitions, theorems etc., including any derived mechanism
  2518 that has been implemented on top of these primitives.  This concept
  2519 generalizes the existing ``theorem (in ...)'' towards more versatility
  2520 and scalability.
  2521 
  2522 * Proof General interface: proper undo of final 'end' command;
  2523 discontinued Isabelle/classic mode (ML proof scripts).
  2524 
  2525 
  2526 *** Document preparation ***
  2527 
  2528 * Added antiquotation @{theory name} which prints the given name,
  2529 after checking that it refers to a valid ancestor theory in the
  2530 current context.
  2531 
  2532 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  2533 check the given source text as ML type/structure, printing verbatim.
  2534 
  2535 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  2536 "c args == rhs" given in the current context.  (Any number of
  2537 arguments may be given on the LHS.)
  2538 
  2539 
  2540 *** Pure ***
  2541 
  2542 * The 'class' package offers a combination of axclass and locale to
  2543 achieve Haskell-like type classes in Isabelle.  Definitions and
  2544 theorems within a class context produce both relative results (with
  2545 implicit parameters according to the locale context), and polymorphic
  2546 constants with qualified polymorphism (according to the class
  2547 context).  Within the body context of a 'class' target, a separate
  2548 syntax layer ("user space type system") takes care of converting
  2549 between global polymorphic consts and internal locale representation.
  2550 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  2551 "isatool doc classes" provides a tutorial.
  2552 
  2553 * Generic code generator framework allows to generate executable
  2554 code for ML and Haskell (including Isabelle classes).  A short usage
  2555 sketch:
  2556 
  2557     internal compilation:
  2558         export_code <list of constants (term syntax)> in SML
  2559     writing SML code to a file:
  2560         export_code <list of constants (term syntax)> in SML <filename>
  2561     writing OCaml code to a file:
  2562         export_code <list of constants (term syntax)> in OCaml <filename>
  2563     writing Haskell code to a bunch of files:
  2564         export_code <list of constants (term syntax)> in Haskell <filename>
  2565 
  2566     evaluating closed propositions to True/False using code generation:
  2567         method ``eval''
  2568 
  2569 Reasonable default setup of framework in HOL.
  2570 
  2571 Theorem attributs for selecting and transforming function equations theorems:
  2572 
  2573     [code fun]:        select a theorem as function equation for a specific constant
  2574     [code fun del]:    deselect a theorem as function equation for a specific constant
  2575     [code inline]:     select an equation theorem for unfolding (inlining) in place
  2576     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  2577 
  2578 User-defined serializations (target in {SML, OCaml, Haskell}):
  2579 
  2580     code_const <and-list of constants (term syntax)>
  2581       {(target) <and-list of const target syntax>}+
  2582 
  2583     code_type <and-list of type constructors>
  2584       {(target) <and-list of type target syntax>}+
  2585 
  2586     code_instance <and-list of instances>
  2587       {(target)}+
  2588         where instance ::= <type constructor> :: <class>
  2589 
  2590     code_class <and_list of classes>
  2591       {(target) <and-list of class target syntax>}+
  2592         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  2593 
  2594 code_instance and code_class only are effective to target Haskell.
  2595 
  2596 For example usage see src/HOL/ex/Codegenerator.thy and
  2597 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  2598 generation from Isabelle/HOL theories is available via "isatool doc
  2599 codegen".
  2600 
  2601 * Code generator: consts in 'consts_code' Isar commands are now
  2602 referred to by usual term syntax (including optional type
  2603 annotations).
  2604 
  2605 * Command 'no_translations' removes translation rules from theory
  2606 syntax.
  2607 
  2608 * Overloaded definitions are now actually checked for acyclic
  2609 dependencies.  The overloading scheme is slightly more general than
  2610 that of Haskell98, although Isabelle does not demand an exact
  2611 correspondence to type class and instance declarations.
  2612 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  2613 exotic versions of overloading -- at the discretion of the user!
  2614 
  2615 Polymorphic constants are represented via type arguments, i.e. the
  2616 instantiation that matches an instance against the most general
  2617 declaration given in the signature.  For example, with the declaration
  2618 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  2619 as c(nat).  Overloading is essentially simultaneous structural
  2620 recursion over such type arguments.  Incomplete specification patterns
  2621 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  2622 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  2623 Command 'print_theory' outputs the normalized system of recursive
  2624 equations, see section "definitions".
  2625 
  2626 * Configuration options are maintained within the theory or proof
  2627 context (with name and type bool/int/string), providing a very simple
  2628 interface to a poor-man's version of general context data.  Tools may
  2629 declare options in ML (e.g. using Attrib.config_int) and then refer to
  2630 these values using Config.get etc.  Users may change options via an
  2631 associated attribute of the same name.  This form of context
  2632 declaration works particularly well with commands 'declare' or
  2633 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  2634 very easy to avoid global references, which would not observe Isar
  2635 toplevel undo/redo and fail to work with multithreading.
  2636 
  2637 Various global ML references of Pure and HOL have been turned into
  2638 configuration options:
  2639 
  2640   Unify.search_bound		unify_search_bound
  2641   Unify.trace_bound		unify_trace_bound
  2642   Unify.trace_simp		unify_trace_simp
  2643   Unify.trace_types		unify_trace_types
  2644   Simplifier.simp_depth_limit	simp_depth_limit
  2645   Blast.depth_limit		blast_depth_limit
  2646   DatatypeProp.dtK		datatype_distinctness_limit
  2647   fast_arith_neq_limit  	fast_arith_neq_limit
  2648   fast_arith_split_limit	fast_arith_split_limit
  2649 
  2650 * Named collections of theorems may be easily installed as context
  2651 data using the functor NamedThmsFun (see also
  2652 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  2653 attributes; there is also a toplevel print command.  This facility is
  2654 just a common case of general context data, which is the preferred way
  2655 for anything more complex than just a list of facts in canonical
  2656 order.
  2657 
  2658 * Isar: command 'declaration' augments a local theory by generic
  2659 declaration functions written in ML.  This enables arbitrary content
  2660 being added to the context, depending on a morphism that tells the
  2661 difference of the original declaration context wrt. the application
  2662 context encountered later on.
  2663 
  2664 * Isar: proper interfaces for simplification procedures.  Command
  2665 'simproc_setup' declares named simprocs (with match patterns, and body
  2666 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  2667 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  2668 
  2669 * Isar: an extra pair of brackets around attribute declarations
  2670 abbreviates a theorem reference involving an internal dummy fact,
  2671 which will be ignored later --- only the effect of the attribute on
  2672 the background context will persist.  This form of in-place
  2673 declarations is particularly useful with commands like 'declare' and
  2674 'using', for example ``have A using [[simproc a]] by simp''.
  2675 
  2676 * Isar: method "assumption" (and implicit closing of subproofs) now
  2677 takes simple non-atomic goal assumptions into account: after applying
  2678 an assumption as a rule the resulting subgoals are solved by atomic
  2679 assumption steps.  This is particularly useful to finish 'obtain'
  2680 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  2681 without referring to the original premise "!!x. P x ==> thesis" in the
  2682 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  2683 more permissive.
  2684 
  2685 * Isar: implicit use of prems from the Isar proof context is
  2686 considered a legacy feature.  Common applications like ``have A .''
  2687 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  2688 referencing facts explicitly here improves readability and
  2689 maintainability of proof texts.
  2690 
  2691 * Isar: improper proof element 'guess' is like 'obtain', but derives
  2692 the obtained context from the course of reasoning!  For example:
  2693 
  2694   assume "EX x y. A x & B y"   -- "any previous fact"
  2695   then guess x and y by clarify
  2696 
  2697 This technique is potentially adventurous, depending on the facts and
  2698 proof tools being involved here.
  2699 
  2700 * Isar: known facts from the proof context may be specified as literal
  2701 propositions, using ASCII back-quote syntax.  This works wherever
  2702 named facts used to be allowed so far, in proof commands, proof
  2703 methods, attributes etc.  Literal facts are retrieved from the context
  2704 according to unification of type and term parameters.  For example,
  2705 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  2706 theorems in the current context, then these are valid literal facts:
  2707 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  2708 
  2709 There is also a proof method "fact" which does the same composition
  2710 for explicit goal states, e.g. the following proof texts coincide with
  2711 certain special cases of literal facts:
  2712 
  2713   have "A" by fact                 ==  note `A`
  2714   have "A ==> B" by fact           ==  note `A ==> B`
  2715   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  2716   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  2717 
  2718 * Isar: ":" (colon) is no longer a symbolic identifier character in
  2719 outer syntax.  Thus symbolic identifiers may be used without
  2720 additional white space in declarations like this: ``assume *: A''.
  2721 
  2722 * Isar: 'print_facts' prints all local facts of the current context,
  2723 both named and unnamed ones.
  2724 
  2725 * Isar: 'def' now admits simultaneous definitions, e.g.:
  2726 
  2727   def x == "t" and y == "u"
  2728 
  2729 * Isar: added command 'unfolding', which is structurally similar to
  2730 'using', but affects both the goal state and facts by unfolding given
  2731 rewrite rules.  Thus many occurrences of the 'unfold' method or
  2732 'unfolded' attribute may be replaced by first-class proof text.
  2733 
  2734 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  2735 and command 'unfolding' now all support object-level equalities
  2736 (potentially conditional).  The underlying notion of rewrite rule is
  2737 analogous to the 'rule_format' attribute, but *not* that of the
  2738 Simplifier (which is usually more generous).
  2739 
  2740 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  2741 premises of a theorem by n. Useful in conjunction with drule.
  2742 
  2743 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  2744 method expression within a sandbox consisting of the first N
  2745 sub-goals, which need to exist.  For example, ``simp_all [3]''
  2746 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  2747 simplifies all new goals that emerge from applying rule foo to the
  2748 originally first one.
  2749 
  2750 * Isar: schematic goals are no longer restricted to higher-order
  2751 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  2752 expected.
  2753 
  2754 * Isar: the conclusion of a long theorem statement is now either
  2755 'shows' (a simultaneous conjunction, as before), or 'obtains'
  2756 (essentially a disjunction of cases with local parameters and
  2757 assumptions).  The latter allows to express general elimination rules
  2758 adequately; in this notation common elimination rules look like this:
  2759 
  2760   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  2761     assumes "EX x. P x"
  2762     obtains x where "P x"
  2763 
  2764   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  2765     assumes "A & B"
  2766     obtains A and B
  2767 
  2768   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  2769     assumes "A | B"
  2770     obtains
  2771       A
  2772     | B
  2773 
  2774 The subsequent classical rules even refer to the formal "thesis"
  2775 explicitly:
  2776 
  2777   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  2778     obtains "~ thesis"
  2779 
  2780   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  2781     obtains "thesis ==> something"
  2782 
  2783 The actual proof of an 'obtains' statement is analogous to that of the
  2784 Isar proof element 'obtain', only that there may be several cases.
  2785 Optional case names may be specified in parentheses; these will be
  2786 available both in the present proof and as annotations in the
  2787 resulting rule, for later use with the 'cases' method (cf. attribute
  2788 case_names).
  2789 
  2790 * Isar: the assumptions of a long theorem statement are available as
  2791 "assms" fact in the proof context.  This is more appropriate than the
  2792 (historical) "prems", which refers to all assumptions of the current
  2793 context, including those from the target locale, proof body etc.
  2794 
  2795 * Isar: 'print_statement' prints theorems from the current theory or
  2796 proof context in long statement form, according to the syntax of a
  2797 top-level lemma.
  2798 
  2799 * Isar: 'obtain' takes an optional case name for the local context
  2800 introduction rule (default "that").
  2801 
  2802 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  2803 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  2804 to occur.
  2805 
  2806 * Pure: syntax "CONST name" produces a fully internalized constant
  2807 according to the current context.  This is particularly useful for
  2808 syntax translations that should refer to internal constant
  2809 representations independently of name spaces.
  2810 
  2811 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  2812 instead of "FOO ". This allows multiple binder declarations to coexist
  2813 in the same context.  INCOMPATIBILITY.
  2814 
  2815 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  2816 primitive that also works in a locale context (both for constants and
  2817 fixed variables). Type declaration and internal syntactic representation
  2818 of given constants retrieved from the context. Likewise, the
  2819 'no_notation' command allows to remove given syntax annotations from the
  2820 current context.
  2821 
  2822 * Isar/locales: new derived specification elements 'axiomatization',
  2823 'definition', 'abbreviation', which support type-inference, admit
  2824 object-level specifications (equality, equivalence).  See also the
  2825 isar-ref manual.  Examples:
  2826 
  2827   axiomatization
  2828     eq  (infix "===" 50) where
  2829     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  2830 
  2831   definition "f x y = x + y + 1"
  2832   definition g where "g x = f x x"
  2833 
  2834   abbreviation
  2835     neq  (infix "=!=" 50) where
  2836     "x =!= y == ~ (x === y)"
  2837 
  2838 These specifications may be also used in a locale context.  Then the
  2839 constants being introduced depend on certain fixed parameters, and the
  2840 constant name is qualified by the locale base name.  An internal
  2841 abbreviation takes care for convenient input and output, making the
  2842 parameters implicit and using the original short name.  See also
  2843 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  2844 entities from a monomorphic theory.
  2845 
  2846 Presently, abbreviations are only available 'in' a target locale, but
  2847 not inherited by general import expressions.  Also note that
  2848 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  2849 'translations' in common applications.  The "no_abbrevs" print mode
  2850 prevents folding of abbreviations in term output.
  2851 
  2852 Concrete syntax is attached to specified constants in internal form,
  2853 independently of name spaces.  The parse tree representation is
  2854 slightly different -- use 'notation' instead of raw 'syntax', and
  2855 'translations' with explicit "CONST" markup to accommodate this.
  2856 
  2857 * Pure/Isar: unified syntax for new-style specification mechanisms
  2858 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  2859 full type inference and dummy patterns ("_").  For example:
  2860 
  2861   definition "K x _ = x"
  2862 
  2863   inductive conj for A B
  2864   where "A ==> B ==> conj A B"
  2865 
  2866 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  2867 the current context.  Print mode "no_abbrevs" prevents inversion of
  2868 abbreviations on output.
  2869 
  2870 * Isar/locales: improved parameter handling: use of locales "var" and
  2871 "struct" no longer necessary; - parameter renamings are no longer
  2872 required to be injective.  For example, this allows to define
  2873 endomorphisms as locale endom = homom mult mult h.
  2874 
  2875 * Isar/locales: changed the way locales with predicates are defined.
  2876 Instead of accumulating the specification, the imported expression is
  2877 now an interpretation.  INCOMPATIBILITY: different normal form of
  2878 locale expressions.  In particular, in interpretations of locales with
  2879 predicates, goals repesenting already interpreted fragments are not
  2880 removed automatically.  Use methods `intro_locales' and
  2881 `unfold_locales'; see below.
  2882 
  2883 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  2884 provide backward reasoning on locales predicates.  The methods are
  2885 aware of interpretations and discharge corresponding goals.
  2886 `intro_locales' is less aggressive then `unfold_locales' and does not
  2887 unfold predicates to assumptions.
  2888 
  2889 * Isar/locales: the order in which locale fragments are accumulated
  2890 has changed.  This enables to override declarations from fragments due
  2891 to interpretations -- for example, unwanted simp rules.
  2892 
  2893 * Isar/locales: interpretation in theories and proof contexts has been
  2894 extended.  One may now specify (and prove) equations, which are
  2895 unfolded in interpreted theorems.  This is useful for replacing
  2896 defined concepts (constants depending on locale parameters) by
  2897 concepts already existing in the target context.  Example:
  2898 
  2899   interpretation partial_order ["op <= :: [int, int] => bool"]
  2900     where "partial_order.less (op <=) (x::int) y = (x < y)"
  2901 
  2902 Typically, the constant `partial_order.less' is created by a
  2903 definition specification element in the context of locale
  2904 partial_order.
  2905 
  2906 * Method "induct": improved internal context management to support
  2907 local fixes and defines on-the-fly. Thus explicit meta-level
  2908 connectives !!  and ==> are rarely required anymore in inductive goals
  2909 (using object-logic connectives for this purpose has been long
  2910 obsolete anyway). Common proof patterns are explained in
  2911 src/HOL/Induct/Common_Patterns.thy, see also
  2912 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  2913 examples.
  2914 
  2915 * Method "induct": improved handling of simultaneous goals. Instead of
  2916 introducing object-level conjunction, the statement is now split into
  2917 several conclusions, while the corresponding symbolic cases are nested
  2918 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  2919 see src/HOL/Induct/Common_Patterns.thy, for example.
  2920 
  2921 * Method "induct": mutual induction rules are now specified as a list
  2922 of rule sharing the same induction cases. HOL packages usually provide
  2923 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  2924 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  2925 mutual induction rules differently, i.e. like this:
  2926 
  2927   (induct rule: foo_bar.inducts)
  2928   (induct set: foo bar)
  2929   (induct pred: foo bar)
  2930   (induct type: foo bar)
  2931 
  2932 The ML function ProjectRule.projections turns old-style rules into the
  2933 new format.
  2934 
  2935 * Method "coinduct": dual of induction, see
  2936 src/HOL/Library/Coinductive_List.thy for various examples.
  2937 
  2938 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  2939 considered a legacy feature.
  2940 
  2941 * Attribute "symmetric" produces result with standardized schematic
  2942 variables (index 0).  Potential INCOMPATIBILITY.
  2943 
  2944 * Simplifier: by default the simplifier trace only shows top level
  2945 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  2946 default. Thus there is less danger of being flooded by the trace. The
  2947 trace indicates where parts have been suppressed.
  2948   
  2949 * Provers/classical: removed obsolete classical version of elim_format
  2950 attribute; classical elim/dest rules are now treated uniformly when
  2951 manipulating the claset.
  2952 
  2953 * Provers/classical: stricter checks to ensure that supplied intro,
  2954 dest and elim rules are well-formed; dest and elim rules must have at
  2955 least one premise.
  2956 
  2957 * Provers/classical: attributes dest/elim/intro take an optional
  2958 weight argument for the rule (just as the Pure versions).  Weights are
  2959 ignored by automated tools, but determine the search order of single
  2960 rule steps.
  2961 
  2962 * Syntax: input syntax now supports dummy variable binding "%_. b",
  2963 where the body does not mention the bound variable.  Note that dummy
  2964 patterns implicitly depend on their context of bounds, which makes
  2965 "{_. _}" match any set comprehension as expected.  Potential
  2966 INCOMPATIBILITY -- parse translations need to cope with syntactic
  2967 constant "_idtdummy" in the binding position.
  2968 
  2969 * Syntax: removed obsolete syntactic constant "_K" and its associated
  2970 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  2971 for example "A -> B" => "Pi A (%_. B)".
  2972 
  2973 * Pure: 'class_deps' command visualizes the subclass relation, using
  2974 the graph browser tool.
  2975 
  2976 * Pure: 'print_theory' now suppresses certain internal declarations by
  2977 default; use '!' option for full details.
  2978 
  2979 
  2980 *** HOL ***
  2981 
  2982 * Method "metis" proves goals by applying the Metis general-purpose
  2983 resolution prover (see also http://gilith.com/software/metis/).
  2984 Examples are in the directory MetisExamples.  WARNING: the
  2985 Isabelle/HOL-Metis integration does not yet work properly with
  2986 multi-threading.
  2987   
  2988 * Command 'sledgehammer' invokes external automatic theorem provers as
  2989 background processes.  It generates calls to the "metis" method if
  2990 successful. These can be pasted into the proof.  Users do not have to
  2991 wait for the automatic provers to return.  WARNING: does not really
  2992 work with multi-threading.
  2993 
  2994 * New "auto_quickcheck" feature tests outermost goal statements for
  2995 potential counter-examples.  Controlled by ML references
  2996 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  2997 5000 milliseconds).  Fails silently if statements is outside of
  2998 executable fragment, or any other codgenerator problem occurs.
  2999 
  3000 * New constant "undefined" with axiom "undefined x = undefined".
  3001 
  3002 * Added class "HOL.eq", allowing for code generation with polymorphic
  3003 equality.
  3004 
  3005 * Some renaming of class constants due to canonical name prefixing in
  3006 the new 'class' package:
  3007 
  3008     HOL.abs ~> HOL.abs_class.abs
  3009     HOL.divide ~> HOL.divide_class.divide
  3010     0 ~> HOL.zero_class.zero
  3011     1 ~> HOL.one_class.one
  3012     op + ~> HOL.plus_class.plus
  3013     op - ~> HOL.minus_class.minus
  3014     uminus ~> HOL.minus_class.uminus
  3015     op * ~> HOL.times_class.times
  3016     op < ~> HOL.ord_class.less
  3017     op <= > HOL.ord_class.less_eq
  3018     Nat.power ~> Power.power_class.power
  3019     Nat.size ~> Nat.size_class.size
  3020     Numeral.number_of ~> Numeral.number_class.number_of
  3021     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3022     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3023     Orderings.min ~> Orderings.ord_class.min
  3024     Orderings.max ~> Orderings.ord_class.max
  3025     Divides.op div ~> Divides.div_class.div
  3026     Divides.op mod ~> Divides.div_class.mod
  3027     Divides.op dvd ~> Divides.div_class.dvd
  3028 
  3029 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3030 
  3031 a) User-defined constants using any of the names "plus", "minus",
  3032 "times", "less" or "less_eq". The standard syntax translations for
  3033 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3034 names.
  3035 
  3036 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3037 INCOMPATIBILITY: use more specific names.
  3038 
  3039 c) Permutative equations (e.g. "a + b = b + a")
  3040 Since the change of names also changes the order of terms, permutative
  3041 rewrite rules may get applied in a different order. Experience shows
  3042 that this is rarely the case (only two adaptions in the whole Isabelle
  3043 distribution).  INCOMPATIBILITY: rewrite proofs
  3044 
  3045 d) ML code directly refering to constant names
  3046 This in general only affects hand-written proof tactics, simprocs and
  3047 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3048 Consider using @{const_name} antiquotation.
  3049 
  3050 * New class "default" with associated constant "default".
  3051 
  3052 * Function "sgn" is now overloaded and available on int, real, complex
  3053 (and other numeric types), using class "sgn".  Two possible defs of
  3054 sgn are given as equational assumptions in the classes sgn_if and
  3055 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3056 INCOMPATIBILITY.
  3057 
  3058 * Locale "partial_order" now unified with class "order" (cf. theory
  3059 Orderings), added parameter "less".  INCOMPATIBILITY.
  3060 
  3061 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3062 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3063 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3064 
  3065 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3066 changed order of proof goals in instance proofs.
  3067 
  3068 * The transitivity reasoner for partial and linear orders is set up
  3069 for classes "order" and "linorder".  Instances of the reasoner are available
  3070 in all contexts importing or interpreting the corresponding locales.
  3071 Method "order" invokes the reasoner separately; the reasoner
  3072 is also integrated with the Simplifier as a solver.  Diagnostic
  3073 command 'print_orders' shows the available instances of the reasoner
  3074 in the current context.
  3075 
  3076 * Localized monotonicity predicate in theory "Orderings"; integrated
  3077 lemmas max_of_mono and min_of_mono with this predicate.
  3078 INCOMPATIBILITY.
  3079 
  3080 * Formulation of theorem "dense" changed slightly due to integration
  3081 with new class dense_linear_order.
  3082 
  3083 * Uniform lattice theory development in HOL.
  3084 
  3085     constants "meet" and "join" now named "inf" and "sup"
  3086     constant "Meet" now named "Inf"
  3087 
  3088     classes "meet_semilorder" and "join_semilorder" now named
  3089       "lower_semilattice" and "upper_semilattice"
  3090     class "lorder" now named "lattice"
  3091     class "comp_lat" now named "complete_lattice"
  3092 
  3093     Instantiation of lattice classes allows explicit definitions
  3094     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3095 
  3096   INCOMPATIBILITY.  Theorem renames:
  3097 
  3098     meet_left_le            ~> inf_le1
  3099     meet_right_le           ~> inf_le2
  3100     join_left_le            ~> sup_ge1
  3101     join_right_le           ~> sup_ge2
  3102     meet_join_le            ~> inf_sup_ord
  3103     le_meetI                ~> le_infI
  3104     join_leI                ~> le_supI
  3105     le_meet                 ~> le_inf_iff
  3106     le_join                 ~> ge_sup_conv
  3107     meet_idempotent         ~> inf_idem
  3108     join_idempotent         ~> sup_idem
  3109     meet_comm               ~> inf_commute
  3110     join_comm               ~> sup_commute
  3111     meet_leI1               ~> le_infI1
  3112     meet_leI2               ~> le_infI2
  3113     le_joinI1               ~> le_supI1
  3114     le_joinI2               ~> le_supI2
  3115     meet_assoc              ~> inf_assoc
  3116     join_assoc              ~> sup_assoc
  3117     meet_left_comm          ~> inf_left_commute
  3118     meet_left_idempotent    ~> inf_left_idem
  3119     join_left_comm          ~> sup_left_commute
  3120     join_left_idempotent    ~> sup_left_idem
  3121     meet_aci                ~> inf_aci
  3122     join_aci                ~> sup_aci
  3123     le_def_meet             ~> le_iff_inf
  3124     le_def_join             ~> le_iff_sup
  3125     join_absorp2            ~> sup_absorb2
  3126     join_absorp1            ~> sup_absorb1
  3127     meet_absorp1            ~> inf_absorb1
  3128     meet_absorp2            ~> inf_absorb2
  3129     meet_join_absorp        ~> inf_sup_absorb
  3130     join_meet_absorp        ~> sup_inf_absorb
  3131     distrib_join_le         ~> distrib_sup_le
  3132     distrib_meet_le         ~> distrib_inf_le
  3133 
  3134     add_meet_distrib_left   ~> add_inf_distrib_left
  3135     add_join_distrib_left   ~> add_sup_distrib_left
  3136     is_join_neg_meet        ~> is_join_neg_inf
  3137     is_meet_neg_join        ~> is_meet_neg_sup
  3138     add_meet_distrib_right  ~> add_inf_distrib_right
  3139     add_join_distrib_right  ~> add_sup_distrib_right
  3140     add_meet_join_distribs  ~> add_sup_inf_distribs
  3141     join_eq_neg_meet        ~> sup_eq_neg_inf
  3142     meet_eq_neg_join        ~> inf_eq_neg_sup
  3143     add_eq_meet_join        ~> add_eq_inf_sup
  3144     meet_0_imp_0            ~> inf_0_imp_0
  3145     join_0_imp_0            ~> sup_0_imp_0
  3146     meet_0_eq_0             ~> inf_0_eq_0
  3147     join_0_eq_0             ~> sup_0_eq_0
  3148     neg_meet_eq_join        ~> neg_inf_eq_sup
  3149     neg_join_eq_meet        ~> neg_sup_eq_inf
  3150     join_eq_if              ~> sup_eq_if
  3151 
  3152     mono_meet               ~> mono_inf
  3153     mono_join               ~> mono_sup
  3154     meet_bool_eq            ~> inf_bool_eq
  3155     join_bool_eq            ~> sup_bool_eq
  3156     meet_fun_eq             ~> inf_fun_eq
  3157     join_fun_eq             ~> sup_fun_eq
  3158     meet_set_eq             ~> inf_set_eq
  3159     join_set_eq             ~> sup_set_eq
  3160     meet1_iff               ~> inf1_iff
  3161     meet2_iff               ~> inf2_iff
  3162     meet1I                  ~> inf1I
  3163     meet2I                  ~> inf2I
  3164     meet1D1                 ~> inf1D1
  3165     meet2D1                 ~> inf2D1
  3166     meet1D2                 ~> inf1D2
  3167     meet2D2                 ~> inf2D2
  3168     meet1E                  ~> inf1E
  3169     meet2E                  ~> inf2E
  3170     join1_iff               ~> sup1_iff
  3171     join2_iff               ~> sup2_iff
  3172     join1I1                 ~> sup1I1
  3173     join2I1                 ~> sup2I1
  3174     join1I1                 ~> sup1I1
  3175     join2I2                 ~> sup1I2
  3176     join1CI                 ~> sup1CI
  3177     join2CI                 ~> sup2CI
  3178     join1E                  ~> sup1E
  3179     join2E                  ~> sup2E
  3180 
  3181     is_meet_Meet            ~> is_meet_Inf
  3182     Meet_bool_def           ~> Inf_bool_def
  3183     Meet_fun_def            ~> Inf_fun_def
  3184     Meet_greatest           ~> Inf_greatest
  3185     Meet_lower              ~> Inf_lower
  3186     Meet_set_def            ~> Inf_set_def
  3187 
  3188     Sup_def                 ~> Sup_Inf
  3189     Sup_bool_eq             ~> Sup_bool_def
  3190     Sup_fun_eq              ~> Sup_fun_def
  3191     Sup_set_eq              ~> Sup_set_def
  3192 
  3193     listsp_meetI            ~> listsp_infI
  3194     listsp_meet_eq          ~> listsp_inf_eq
  3195 
  3196     meet_min                ~> inf_min
  3197     join_max                ~> sup_max
  3198 
  3199 * Added syntactic class "size"; overloaded constant "size" now has
  3200 type "'a::size ==> bool"
  3201 
  3202 * Internal reorganisation of `size' of datatypes: size theorems
  3203 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3204 simplification rules by default!); theorems "prod.size" now named
  3205 "*.size".
  3206 
  3207 * Class "div" now inherits from class "times" rather than "type".
  3208 INCOMPATIBILITY.
  3209 
  3210 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  3211 Linorder etc.  have disappeared; operations defined in terms of
  3212 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  3213 
  3214 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  3215 
  3216 * HOL-Word: New extensive library and type for generic, fixed size
  3217 machine words, with arithemtic, bit-wise, shifting and rotating
  3218 operations, reflection into int, nat, and bool lists, automation for
  3219 linear arithmetic (by automatic reflection into nat or int), including
  3220 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  3221 arithmetic type classes, supporting automatic simplification of
  3222 numerals on all operations.
  3223 
  3224 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  3225 
  3226 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  3227 
  3228 * Code generator library theories:
  3229   - Code_Integer represents HOL integers by big integer literals in target
  3230     languages.
  3231   - Code_Char represents HOL characters by character literals in target
  3232     languages.
  3233   - Code_Char_chr like Code_Char, but also offers treatment of character
  3234     codes; includes Code_Integer.
  3235   - Executable_Set allows to generate code for finite sets using lists.
  3236   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  3237     denominator).
  3238   - Executable_Real implements a subset of real numbers, namly those
  3239     representable by rational numbers.
  3240   - Efficient_Nat implements natural numbers by integers, which in general will
  3241     result in higher efficency; pattern matching with 0/Suc is eliminated;
  3242     includes Code_Integer.
  3243   - Code_Index provides an additional datatype index which is mapped to
  3244     target-language built-in integers.
  3245   - Code_Message provides an additional datatype message_string which is isomorphic to
  3246     strings; messages are mapped to target-language strings.
  3247 
  3248 * New package for inductive predicates
  3249 
  3250   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  3251 
  3252     inductive
  3253       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3254       for z_1 :: U_1 and ... and z_n :: U_m
  3255     where
  3256       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3257     | ...
  3258 
  3259   with full support for type-inference, rather than
  3260 
  3261     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3262 
  3263     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3264     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3265 
  3266     inductive "s z_1 ... z_m"
  3267     intros
  3268       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3269       ...
  3270 
  3271   For backward compatibility, there is a wrapper allowing inductive
  3272   sets to be defined with the new package via
  3273 
  3274     inductive_set
  3275       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3276       for z_1 :: U_1 and ... and z_n :: U_m
  3277     where
  3278       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3279     | ...
  3280 
  3281   or
  3282 
  3283     inductive_set
  3284       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3285       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3286       for z_1 :: U_1 and ... and z_n :: U_m
  3287     where
  3288       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3289     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3290     | ...
  3291 
  3292   if the additional syntax "p ..." is required.
  3293 
  3294   Numerous examples can be found in the subdirectories src/HOL/Auth,
  3295   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  3296 
  3297   INCOMPATIBILITIES:
  3298 
  3299   - Since declaration and definition of inductive sets or predicates
  3300     is no longer separated, abbreviations involving the newly
  3301     introduced sets or predicates must be specified together with the
  3302     introduction rules after the 'where' keyword (see above), rather
  3303     than before the actual inductive definition.
  3304 
  3305   - The variables in induction and elimination rules are now
  3306     quantified in the order of their occurrence in the introduction
  3307     rules, rather than in alphabetical order. Since this may break
  3308     some proofs, these proofs either have to be repaired, e.g. by
  3309     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  3310     statements of the form
  3311 
  3312       case (rule_i a_i_1 ... a_i_{k_i})
  3313 
  3314     or the old order of quantification has to be restored by explicitly adding
  3315     meta-level quantifiers in the introduction rules, i.e.
  3316 
  3317       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  3318 
  3319   - The format of the elimination rules is now
  3320 
  3321       p z_1 ... z_m x_1 ... x_n ==>
  3322         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3323         ==> ... ==> P
  3324 
  3325     for predicates and
  3326 
  3327       (x_1, ..., x_n) : s z_1 ... z_m ==>
  3328         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3329         ==> ... ==> P
  3330 
  3331     for sets rather than
  3332 
  3333       x : s z_1 ... z_m ==>
  3334         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  3335         ==> ... ==> P
  3336 
  3337     This may require terms in goals to be expanded to n-tuples
  3338     (e.g. using case_tac or simplification with the split_paired_all
  3339     rule) before the above elimination rule is applicable.
  3340 
  3341   - The elimination or case analysis rules for (mutually) inductive
  3342     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  3343     list of rules "p_1_..._p_k.elims" is no longer available.
  3344 
  3345 * New package "function"/"fun" for general recursive functions,
  3346 supporting mutual and nested recursion, definitions in local contexts,
  3347 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  3348 for small examples, and the separate tutorial on the function
  3349 package. The old recdef "package" is still available as before, but
  3350 users are encouraged to use the new package.
  3351 
  3352 * Method "lexicographic_order" automatically synthesizes termination
  3353 relations as lexicographic combinations of size measures. 
  3354 
  3355 * Case-expressions allow arbitrary constructor-patterns (including
  3356 "_") and take their order into account, like in functional
  3357 programming.  Internally, this is translated into nested
  3358 case-expressions; missing cases are added and mapped to the predefined
  3359 constant "undefined". In complicated cases printing may no longer show
  3360 the original input but the internal form. Lambda-abstractions allow
  3361 the same form of pattern matching: "% pat1 => e1 | ..." is an
  3362 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  3363 variable.
  3364 
  3365 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  3366 is an abbreviation for "of_nat :: nat => int". The simplification
  3367 rules for "of_nat" have been changed to work like "int" did
  3368 previously.  Potential INCOMPATIBILITY:
  3369   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  3370   - of_nat_diff and of_nat_mult are no longer default simp rules
  3371 
  3372 * Method "algebra" solves polynomial equations over (semi)rings using
  3373 Groebner bases. The (semi)ring structure is defined by locales and the
  3374 tool setup depends on that generic context. Installing the method for
  3375 a specific type involves instantiating the locale and possibly adding
  3376 declarations for computation on the coefficients.  The method is
  3377 already instantiated for natural numbers and for the axiomatic class
  3378 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  3379 CALCULEMUS 2007 for the general principles underlying this
  3380 architecture of context-aware proof-tools.
  3381 
  3382 * Method "ferrack" implements quantifier elimination over
  3383 special-purpose dense linear orders using locales (analogous to
  3384 "algebra"). The method is already installed for class
  3385 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  3386 rat, etc.
  3387 
  3388 * Former constant "List.op @" now named "List.append".  Use ML
  3389 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  3390 circumvent possible incompatibilities when working on ML level.
  3391 
  3392 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  3393 
  3394 * New function listsum :: 'a list => 'a for arbitrary monoids.
  3395 Special syntax: "SUM x <- xs. f x" (and latex variants)
  3396 
  3397 * New syntax for Haskell-like list comprehension (input only), eg.
  3398 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  3399 
  3400 * The special syntax for function "filter" has changed from [x :
  3401 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  3402 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  3403 
  3404 * [a..b] is now defined for arbitrary linear orders.  It used to be
  3405 defined on nat only, as an abbreviation for [a..<Suc b]
  3406 INCOMPATIBILITY.
  3407 
  3408 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  3409 
  3410 * New functions "sorted" and "sort" in src/HOL/List.thy.
  3411 
  3412 * New lemma collection field_simps (an extension of ring_simps) for
  3413 manipulating (in)equations involving division. Multiplies with all
  3414 denominators that can be proved to be non-zero (in equations) or
  3415 positive/negative (in inequations).
  3416 
  3417 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  3418 have been improved and renamed to ring_simps, group_simps and
  3419 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  3420 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  3421 
  3422 * Theory Library/Commutative_Ring: switched from recdef to function
  3423 package; constants add, mul, pow now curried.  Infix syntax for
  3424 algebraic operations.
  3425 
  3426 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  3427 INCOMPATIBILITY.
  3428 
  3429 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  3430 INCOMPATIBILITY.
  3431 
  3432 * HOL/records: generalised field-update to take a function on the
  3433 field rather than the new value: r(|A := x|) is translated to A_update
  3434 (K x) r The K-combinator that is internally used is called K_record.
  3435 INCOMPATIBILITY: Usage of the plain update functions has to be
  3436 adapted.
  3437  
  3438 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  3439 * x = 0, which are required for a semiring.  Richer structures do not
  3440 inherit from semiring_0 anymore, because this property is a theorem
  3441 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  3442 there is more to prove, but this is mostly trivial.
  3443 
  3444 * Class "recpower" is generalized to arbitrary monoids, not just
  3445 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  3446 commutativity or semiring properties additionally.
  3447 
  3448 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  3449 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  3450 better use 'abbreviation'.
  3451 
  3452 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  3453 
  3454 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  3455 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  3456 significant changes for setting up numeral syntax for types:
  3457   - New constants Numeral.pred and Numeral.succ instead
  3458       of former Numeral.bin_pred and Numeral.bin_succ.
  3459   - Use integer operations instead of bin_add, bin_mult and so on.
  3460   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  3461   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  3462 
  3463 See src/HOL/Integ/IntArith.thy for an example setup.
  3464 
  3465 * Command 'normal_form' computes the normal form of a term that may
  3466 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  3467 produces ``[b, c, a]'' (without proof).  This command is suitable for
  3468 heavy-duty computations because the functions are compiled to ML
  3469 first.  Correspondingly, a method "normalization" is provided.  See
  3470 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  3471 
  3472 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  3473 25 like -->); output depends on the "iff" print_mode, the default is
  3474 "A = B" (with priority 50).
  3475 
  3476 * Relations less (<) and less_eq (<=) are also available on type bool.
  3477 Modified syntax to disallow nesting without explicit parentheses,
  3478 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  3479 INCOMPATIBILITY.
  3480 
  3481 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  3482 
  3483 * Relation composition operator "op O" now has precedence 75 and binds
  3484 stronger than union and intersection. INCOMPATIBILITY.
  3485 
  3486 * The old set interval syntax "{m..n(}" (and relatives) has been
  3487 removed.  Use "{m..<n}" (and relatives) instead.
  3488 
  3489 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  3490 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  3491 ``declare [[simproc del: neq]]''.
  3492 
  3493 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  3494 True/False.
  3495 
  3496 * Theorem Cons_eq_map_conv no longer declared as "simp".
  3497 
  3498 * Theorem setsum_mult renamed to setsum_right_distrib.
  3499 
  3500 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  3501 ``rule'' method.
  3502 
  3503 * Reimplemented methods "sat" and "satx", with several improvements:
  3504 goals no longer need to be stated as "<prems> ==> False", equivalences
  3505 (i.e. "=" on type bool) are handled, variable names of the form
  3506 "lit_<n>" are no longer reserved, significant speedup.
  3507 
  3508 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  3509 zChaff is still supported as well.
  3510 
  3511 * 'inductive' and 'datatype': provide projections of mutual rules,
  3512 bundled as foo_bar.inducts;
  3513 
  3514 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  3515 Library.
  3516 
  3517 * Library: moved theory Accessible_Part to main HOL.
  3518 
  3519 * Library: added theory Coinductive_List of potentially infinite lists
  3520 as greatest fixed-point.
  3521 
  3522 * Library: added theory AssocList which implements (finite) maps as
  3523 association lists.
  3524 
  3525 * Method "evaluation" solves goals (i.e. a boolean expression)
  3526 efficiently by compiling it to ML.  The goal is "proved" (via an
  3527 oracle) if it evaluates to True.
  3528 
  3529 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  3530 also when invoked by the simplifier.  This results in the Simplifier
  3531 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  3532 Configuration option fast_arith_split_limit=0 recovers the old
  3533 behavior.
  3534 
  3535 * Support for hex (0x20) and binary (0b1001) numerals.
  3536 
  3537 * New method: reify eqs (t), where eqs are equations for an
  3538 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  3539 parameter, computes a term s::'b and a list xs::'a list and proves the
  3540 theorem I xs s = t. This is also known as reification or quoting. The
  3541 resulting theorem is applied to the subgoal to substitute t with I xs
  3542 s.  If t is omitted, the subgoal itself is reified.
  3543 
  3544 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  3545 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  3546 where f is supposed to be a computable function (in the sense of code
  3547 generattion). The method uses reify to compute s and xs as above then
  3548 applies corr_thm and uses normalization by evaluation to "prove" f s =
  3549 r and finally gets the theorem t = r, which is again applied to the
  3550 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  3551 
  3552 * Reflection: Automatic reification now handels binding, an example is
  3553 available in src/HOL/ex/ReflectionEx.thy
  3554 
  3555 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  3556 command 'statespace' that is similar to 'record', but introduces an
  3557 abstract specification based on the locale infrastructure instead of
  3558 HOL types.  This leads to extra flexibility in composing state spaces,
  3559 in particular multiple inheritance and renaming of components.
  3560 
  3561 
  3562 *** HOL-Complex ***
  3563 
  3564 * Hyperreal: Functions root and sqrt are now defined on negative real
  3565 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  3566 Nonnegativity side conditions have been removed from many lemmas, so
  3567 that more subgoals may now be solved by simplification; potential
  3568 INCOMPATIBILITY.
  3569 
  3570 * Real: new type classes formalize real normed vector spaces and
  3571 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  3572 and norm :: 'a => real.
  3573 
  3574 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  3575 reals into other types. The overloaded constant Reals :: 'a set is now
  3576 defined as range of_real; potential INCOMPATIBILITY.
  3577 
  3578 * Real: proper support for ML code generation, including 'quickcheck'.
  3579 Reals are implemented as arbitrary precision rationals.
  3580 
  3581 * Hyperreal: Several constants that previously worked only for the
  3582 reals have been generalized, so they now work over arbitrary vector
  3583 spaces. Type annotations may need to be added in some cases; potential
  3584 INCOMPATIBILITY.
  3585 
  3586   Infinitesimal  :: ('a::real_normed_vector) star set
  3587   HFinite        :: ('a::real_normed_vector) star set
  3588   HInfinite      :: ('a::real_normed_vector) star set
  3589   approx         :: ('a::real_normed_vector) star => 'a star => bool
  3590   monad          :: ('a::real_normed_vector) star => 'a star set
  3591   galaxy         :: ('a::real_normed_vector) star => 'a star set
  3592   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  3593   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  3594   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  3595   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  3596   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  3597   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  3598   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  3599   sgn            :: 'a::real_normed_vector => 'a
  3600   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  3601 
  3602 * Complex: Some complex-specific constants are now abbreviations for
  3603 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  3604 hnorm.  Other constants have been entirely removed in favor of the
  3605 polymorphic versions (INCOMPATIBILITY):
  3606 
  3607   approx        <-- capprox
  3608   HFinite       <-- CFinite
  3609   HInfinite     <-- CInfinite
  3610   Infinitesimal <-- CInfinitesimal
  3611   monad         <-- cmonad
  3612   galaxy        <-- cgalaxy
  3613   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  3614   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  3615   (ns)deriv     <-- (ns)cderiv
  3616 
  3617 
  3618 *** HOL-Algebra ***
  3619 
  3620 * Formalisation of ideals and the quotient construction over rings.
  3621 
  3622 * Order and lattice theory no longer based on records.
  3623 INCOMPATIBILITY.
  3624 
  3625 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  3626 greatest_closed.  INCOMPATIBILITY.
  3627 
  3628 * Method algebra is now set up via an attribute.  For examples see
  3629 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  3630 of algebraic structures.
  3631 
  3632 * Renamed theory CRing to Ring.
  3633 
  3634 
  3635 *** HOL-Nominal ***
  3636 
  3637 * Substantial, yet incomplete support for nominal datatypes (binding
  3638 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  3639 src/HOL/Nominal/Examples.  Prospective users should consult
  3640 http://isabelle.in.tum.de/nominal/
  3641 
  3642 
  3643 *** ML ***
  3644 
  3645 * ML basics: just one true type int, which coincides with IntInf.int
  3646 (even on SML/NJ).
  3647 
  3648 * ML within Isar: antiquotations allow to embed statically-checked
  3649 formal entities in the source, referring to the context available at
  3650 compile-time.  For example:
  3651 
  3652 ML {* @{sort "{zero,one}"} *}
  3653 ML {* @{typ "'a => 'b"} *}
  3654 ML {* @{term "%x. x"} *}
  3655 ML {* @{prop "x == y"} *}
  3656 ML {* @{ctyp "'a => 'b"} *}
  3657 ML {* @{cterm "%x. x"} *}
  3658 ML {* @{cprop "x == y"} *}
  3659 ML {* @{thm asm_rl} *}
  3660 ML {* @{thms asm_rl} *}
  3661 ML {* @{type_name c} *}
  3662 ML {* @{type_syntax c} *}
  3663 ML {* @{const_name c} *}
  3664 ML {* @{const_syntax c} *}
  3665 ML {* @{context} *}
  3666 ML {* @{theory} *}
  3667 ML {* @{theory Pure} *}
  3668 ML {* @{theory_ref} *}
  3669 ML {* @{theory_ref Pure} *}
  3670 ML {* @{simpset} *}
  3671 ML {* @{claset} *}
  3672 ML {* @{clasimpset} *}
  3673 
  3674 The same works for sources being ``used'' within an Isar context.
  3675 
  3676 * ML in Isar: improved error reporting; extra verbosity with
  3677 ML_Context.trace enabled.
  3678 
  3679 * Pure/General/table.ML: the join operations now works via exceptions
  3680 DUP/SAME instead of type option. This is simpler in simple cases, and
  3681 admits slightly more efficient complex applications.
  3682 
  3683 * Pure: 'advanced' translation functions (parse_translation etc.) now
  3684 use Context.generic instead of just theory.
  3685 
  3686 * Pure: datatype Context.generic joins theory/Proof.context and
  3687 provides some facilities for code that works in either kind of
  3688 context, notably GenericDataFun for uniform theory and proof data.
  3689 
  3690 * Pure: simplified internal attribute type, which is now always
  3691 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  3692 local (Proof.context) attributes have been discontinued, while
  3693 minimizing code duplication. Thm.rule_attribute and
  3694 Thm.declaration_attribute build canonical attributes; see also structure
  3695 Context for further operations on Context.generic, notably
  3696 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  3697 declarations and definitions.
  3698 
  3699 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  3700 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  3701 init only required for impure data. INCOMPATIBILITY: empty really need
  3702 to be empty (no dependencies on theory content!)
  3703 
  3704 * Pure/kernel: consts certification ignores sort constraints given in
  3705 signature declarations. (This information is not relevant to the
  3706 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  3707 potential INCOMPATIBILITY.
  3708 
  3709 * Pure: axiomatic type classes are now purely definitional, with
  3710 explicit proofs of class axioms and super class relations performed
  3711 internally. See Pure/axclass.ML for the main internal interfaces --
  3712 notably AxClass.define_class supercedes AxClass.add_axclass, and
  3713 AxClass.axiomatize_class/classrel/arity supersede
  3714 Sign.add_classes/classrel/arities.
  3715 
  3716 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  3717 global/local versions on theory vs. Proof.context have been
  3718 discontinued; Attrib.syntax and Method.syntax have been adapted
  3719 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  3720 attributes, methods, etc.
  3721 
  3722 * Pure: several functions of signature "... -> theory -> theory * ..."
  3723 have been reoriented to "... -> theory -> ... * theory" in order to
  3724 allow natural usage in combination with the ||>, ||>>, |-> and
  3725 fold_map combinators.
  3726 
  3727 * Pure: official theorem names (closed derivations) and additional
  3728 comments (tags) are now strictly separate.  Name hints -- which are
  3729 maintained as tags -- may be attached any time without affecting the
  3730 derivation.
  3731 
  3732 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  3733 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  3734 achieve the old behaviour.
  3735 
  3736 * Pure: the "Goal" constant is now called "prop", supporting a
  3737 slightly more general idea of ``protecting'' meta-level rule
  3738 statements.
  3739 
  3740 * Pure: Logic.(un)varify only works in a global context, which is now
  3741 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  3742 Logic.legacy_(un)varify as temporary workaround.
  3743 
  3744 * Pure: structure Name provides scalable operations for generating
  3745 internal variable names, notably Name.variants etc.  This replaces
  3746 some popular functions from term.ML:
  3747 
  3748   Term.variant		->  Name.variant
  3749   Term.variantlist	->  Name.variant_list
  3750   Term.invent_names	->  Name.invent_list
  3751 
  3752 Note that low-level renaming rarely occurs in new code -- operations
  3753 from structure Variable are used instead (see below).
  3754 
  3755 * Pure: structure Variable provides fundamental operations for proper
  3756 treatment of fixed/schematic variables in a context.  For example,
  3757 Variable.import introduces fixes for schematics of given facts and
  3758 Variable.export reverses the effect (up to renaming) -- this replaces
  3759 various freeze_thaw operations.
  3760 
  3761 * Pure: structure Goal provides simple interfaces for
  3762 init/conclude/finish and tactical prove operations (replacing former
  3763 Tactic.prove).  Goal.prove is the canonical way to prove results
  3764 within a given context; Goal.prove_global is a degraded version for
  3765 theory level goals, including a global Drule.standard.  Note that
  3766 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  3767 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  3768 in a locale context).
  3769 
  3770 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  3771 and type checking (Syntax.check_term etc.), with common combinations
  3772 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  3773 which are considered legacy and await removal.
  3774 
  3775 * Pure/Syntax: generic interfaces for type unchecking
  3776 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  3777 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  3778 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  3779 available for convenience, but refer to the very same operations using
  3780 a mere theory instead of a full context.
  3781 
  3782 * Isar: simplified treatment of user-level errors, using exception
  3783 ERROR of string uniformly.  Function error now merely raises ERROR,
  3784 without any side effect on output channels.  The Isar toplevel takes
  3785 care of proper display of ERROR exceptions.  ML code may use plain
  3786 handle/can/try; cat_error may be used to concatenate errors like this:
  3787 
  3788   ... handle ERROR msg => cat_error msg "..."
  3789 
  3790 Toplevel ML code (run directly or through the Isar toplevel) may be
  3791 embedded into the Isar toplevel with exception display/debug like
  3792 this:
  3793 
  3794   Isar.toplevel (fn () => ...)
  3795 
  3796 INCOMPATIBILITY, removed special transform_error facilities, removed
  3797 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  3798 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  3799 -- use plain ERROR instead.
  3800 
  3801 * Isar: theory setup now has type (theory -> theory), instead of a
  3802 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  3803 
  3804 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  3805 ProofContext.debug/verbose flags.
  3806 
  3807 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  3808 theory before entering a proof state.  Transactions now always see a
  3809 quasi-functional intermediate checkpoint, both in interactive and
  3810 batch mode.
  3811 
  3812 * Isar: simplified interfaces for outer syntax.  Renamed
  3813 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  3814 OuterSyntax.add_parsers -- this functionality is now included in
  3815 OuterSyntax.command etc.  INCOMPATIBILITY.
  3816 
  3817 * Simplifier: the simpset of a running simplification process now
  3818 contains a proof context (cf. Simplifier.the_context), which is the
  3819 very context that the initial simpset has been retrieved from (by
  3820 simpset_of/local_simpset_of).  Consequently, all plug-in components
  3821 (solver, looper etc.) may depend on arbitrary proof data.
  3822 
  3823 * Simplifier.inherit_context inherits the proof context (plus the
  3824 local bounds) of the current simplification process; any simproc
  3825 etc. that calls the Simplifier recursively should do this!  Removed
  3826 former Simplifier.inherit_bounds, which is already included here --
  3827 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  3828 specify an explicit context using Simplifier.context/theory_context.
  3829 
  3830 * Simplifier/Classical Reasoner: more abstract interfaces
  3831 change_simpset/claset for modifying the simpset/claset reference of a
  3832 theory; raw versions simpset/claset_ref etc. have been discontinued --
  3833 INCOMPATIBILITY.
  3834 
  3835 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  3836 "Trueprop" etc.
  3837 
  3838 
  3839 *** System ***
  3840 
  3841 * settings: the default heap location within ISABELLE_HOME_USER now
  3842 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  3843 Isabelle installations.
  3844 
  3845 * isabelle-process: option -S (secure mode) disables some critical
  3846 operations, notably runtime compilation and evaluation of ML source
  3847 code.
  3848 
  3849 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  3850 
  3851 * Support for parallel execution, using native multicore support of
  3852 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  3853 independent theories, according to the given theory header
  3854 specifications. The maximum number of worker threads is specified via
  3855 usedir option -M or the "max-threads" setting in Proof General. A
  3856 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  3857 to 6 on a 8-core machine.  User-code needs to observe certain
  3858 guidelines for thread-safe programming, see appendix A in the Isar
  3859 Implementation manual.
  3860 
  3861 
  3862 
  3863 New in Isabelle2005 (October 2005)
  3864 ----------------------------------
  3865 
  3866 *** General ***
  3867 
  3868 * Theory headers: the new header syntax for Isar theories is
  3869 
  3870   theory <name>
  3871   imports <theory1> ... <theoryN>
  3872   uses <file1> ... <fileM>
  3873   begin
  3874 
  3875 where the 'uses' part is optional.  The previous syntax
  3876 
  3877   theory <name> = <theory1> + ... + <theoryN>:
  3878 
  3879 will disappear in the next release.  Use isatool fixheaders to convert
  3880 existing theory files.  Note that there is no change in ancient
  3881 non-Isar theories now, but these will disappear soon.
  3882 
  3883 * Theory loader: parent theories can now also be referred to via
  3884 relative and absolute paths.
  3885 
  3886 * Command 'find_theorems' searches for a list of criteria instead of a
  3887 list of constants. Known criteria are: intro, elim, dest, name:string,
  3888 simp:term, and any term. Criteria can be preceded by '-' to select
  3889 theorems that do not match. Intro, elim, dest select theorems that
  3890 match the current goal, name:s selects theorems whose fully qualified
  3891 name contain s, and simp:term selects all simplification rules whose
  3892 lhs match term.  Any other term is interpreted as pattern and selects
  3893 all theorems matching the pattern. Available in ProofGeneral under
  3894 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  3895 
  3896   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  3897 
  3898 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  3899 matching the current goal as introduction rule and not having "HOL."
  3900 in their name (i.e. not being defined in theory HOL).
  3901 
  3902 * Command 'thms_containing' has been discontinued in favour of
  3903 'find_theorems'; INCOMPATIBILITY.
  3904 
  3905 * Communication with Proof General is now 8bit clean, which means that
  3906 Unicode text in UTF-8 encoding may be used within theory texts (both
  3907 formal and informal parts).  Cf. option -U of the Isabelle Proof
  3908 General interface.  Here are some simple examples (cf. src/HOL/ex):
  3909 
  3910   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  3911   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  3912 
  3913 * Improved efficiency of the Simplifier and, to a lesser degree, the
  3914 Classical Reasoner.  Typical big applications run around 2 times
  3915 faster.
  3916 
  3917 
  3918 *** Document preparation ***
  3919 
  3920 * Commands 'display_drafts' and 'print_drafts' perform simple output
  3921 of raw sources.  Only those symbols that do not require additional
  3922 LaTeX packages (depending on comments in isabellesym.sty) are
  3923 displayed properly, everything else is left verbatim.  isatool display
  3924 and isatool print are used as front ends (these are subject to the
  3925 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  3926 
  3927 * Command tags control specific markup of certain regions of text,
  3928 notably folding and hiding.  Predefined tags include "theory" (for
  3929 theory begin and end), "proof" for proof commands, and "ML" for
  3930 commands involving ML code; the additional tags "visible" and
  3931 "invisible" are unused by default.  Users may give explicit tag
  3932 specifications in the text, e.g. ''by %invisible (auto)''.  The
  3933 interpretation of tags is determined by the LaTeX job during document
  3934 preparation: see option -V of isatool usedir, or options -n and -t of
  3935 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  3936 \isadroptag.
  3937 
  3938 Several document versions may be produced at the same time via isatool
  3939 usedir (the generated index.html will link all of them).  Typical
  3940 specifications include ''-V document=theory,proof,ML'' to present
  3941 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  3942 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  3943 these parts without any formal replacement text.  The Isabelle site
  3944 default settings produce ''document'' and ''outline'' versions as
  3945 specified above.
  3946 
  3947 * Several new antiquotations:
  3948 
  3949   @{term_type term} prints a term with its type annotated;
  3950 
  3951   @{typeof term} prints the type of a term;
  3952 
  3953   @{const const} is the same as @{term const}, but checks that the
  3954   argument is a known logical constant;
  3955 
  3956   @{term_style style term} and @{thm_style style thm} print a term or
  3957   theorem applying a "style" to it
  3958 
  3959   @{ML text}
  3960 
  3961 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  3962 definitions, equations, inequations etc., 'concl' printing only the
  3963 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  3964 to print the specified premise.  TermStyle.add_style provides an ML
  3965 interface for introducing further styles.  See also the "LaTeX Sugar"
  3966 document practical applications.  The ML antiquotation prints
  3967 type-checked ML expressions verbatim.
  3968 
  3969 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  3970 and 'text' support optional locale specification '(in loc)', which
  3971 specifies the default context for interpreting antiquotations.  For
  3972 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  3973 
  3974 * Option 'locale=NAME' of antiquotations specifies an alternative
  3975 context interpreting the subsequent argument.  For example: @{thm
  3976 [locale=lattice] inf_assoc}.
  3977 
  3978 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  3979 a proof context.
  3980 
  3981 * Proper output of antiquotations for theory commands involving a
  3982 proof context (such as 'locale' or 'theorem (in loc) ...').
  3983 
  3984 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  3985 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  3986 
  3987 * isatool usedir: new option -C (default true) controls whether option
  3988 -D should include a copy of the original document directory; -C false
  3989 prevents unwanted effects such as copying of administrative CVS data.
  3990 
  3991 
  3992 *** Pure ***
  3993 
  3994 * Considerably improved version of 'constdefs' command.  Now performs
  3995 automatic type-inference of declared constants; additional support for
  3996 local structure declarations (cf. locales and HOL records), see also
  3997 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  3998 sequential dependencies of definitions within a single 'constdefs'
  3999 section; moreover, the declared name needs to be an identifier.  If
  4000 all fails, consider to fall back on 'consts' and 'defs' separately.
  4001 
  4002 * Improved indexed syntax and implicit structures.  First of all,
  4003 indexed syntax provides a notational device for subscripted
  4004 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4005 expressions.  Secondly, in a local context with structure
  4006 declarations, number indexes \<^sub>n or the empty index (default
  4007 number 1) refer to a certain fixed variable implicitly; option
  4008 show_structs controls printing of implicit structures.  Typical
  4009 applications of these concepts involve record types and locales.
  4010 
  4011 * New command 'no_syntax' removes grammar declarations (and
  4012 translations) resulting from the given syntax specification, which is
  4013 interpreted in the same manner as for the 'syntax' command.
  4014 
  4015 * 'Advanced' translation functions (parse_translation etc.) may depend
  4016 on the signature of the theory context being presently used for
  4017 parsing/printing, see also isar-ref manual.
  4018 
  4019 * Improved 'oracle' command provides a type-safe interface to turn an
  4020 ML expression of type theory -> T -> term into a primitive rule of
  4021 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4022 is already included here); see also FOL/ex/IffExample.thy;
  4023 INCOMPATIBILITY.
  4024 
  4025 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4026 before); "cI" is no longer bound, use "c.intro" instead.
  4027 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4028 axclasses vs. locales.
  4029 
  4030 * Improved internal renaming of symbolic identifiers -- attach primes
  4031 instead of base 26 numbers.
  4032 
  4033 * New flag show_question_marks controls printing of leading question
  4034 marks in schematic variable names.
  4035 
  4036 * In schematic variable names, *any* symbol following \<^isub> or
  4037 \<^isup> is now treated as part of the base name.  For example, the
  4038 following works without printing of awkward ".0" indexes:
  4039 
  4040   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4041     by simp
  4042 
  4043 * Inner syntax includes (*(*nested*) comments*).
  4044 
  4045 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4046 annotations as "(00...)".
  4047 
  4048 * Clear separation of logical types and nonterminals, where the latter
  4049 may only occur in 'syntax' specifications or type abbreviations.
  4050 Before that distinction was only partially implemented via type class
  4051 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4052 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4053 exotic syntax specifications may require further adaption
  4054 (e.g. Cube/Cube.thy).
  4055 
  4056 * Removed obsolete type class "logic", use the top sort {} instead.
  4057 Note that non-logical types should be declared as 'nonterminals'
  4058 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4059 specifications.
  4060 
  4061 * Attributes 'induct' and 'cases': type or set names may now be
  4062 locally fixed variables as well.
  4063 
  4064 * Simplifier: can now control the depth to which conditional rewriting
  4065 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4066 Limit.
  4067 
  4068 * Simplifier: simplification procedures may now take the current
  4069 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4070 interface), which is very useful for calling the Simplifier
  4071 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4072 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4073 low-level mk_simproc no longer applies Logic.varify internally, to
  4074 allow for use in a context of fixed variables.
  4075 
  4076 * thin_tac now works even if the assumption being deleted contains !!
  4077 or ==>.  More generally, erule now works even if the major premise of
  4078 the elimination rule contains !! or ==>.
  4079 
  4080 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4081 
  4082 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4083 from Pure, which contains all common declarations already.  Both
  4084 theories are defined via plain Isabelle/Isar .thy files.
  4085 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4086 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4087 use isatool fixcpure to adapt your theory and ML sources.
  4088 
  4089 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4090 selections of theorems in named facts via index ranges.
  4091 
  4092 * 'print_theorems': in theory mode, really print the difference
  4093 wrt. the last state (works for interactive theory development only),
  4094 in proof mode print all local facts (cf. 'print_facts');
  4095 
  4096 * 'hide': option '(open)' hides only base names.
  4097 
  4098 * More efficient treatment of intermediate checkpoints in interactive
  4099 theory development.
  4100 
  4101 * Code generator is now invoked via code_module (incremental code
  4102 generation) and code_library (modular code generation, ML structures
  4103 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4104 must be quoted when used as identifiers.
  4105 
  4106 * New 'value' command for reading, evaluating and printing terms using
  4107 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4108 quoted when used as identifier.
  4109 
  4110 
  4111 *** Locales ***
  4112 
  4113 * New commands for the interpretation of locale expressions in
  4114 theories (1), locales (2) and proof contexts (3).  These generate
  4115 proof obligations from the expression specification.  After the
  4116 obligations have been discharged, theorems of the expression are added
  4117 to the theory, target locale or proof context.  The synopsis of the
  4118 commands is a follows:
  4119 
  4120   (1) interpretation expr inst
  4121   (2) interpretation target < expr
  4122   (3) interpret expr inst
  4123 
  4124 Interpretation in theories and proof contexts require a parameter
  4125 instantiation of terms from the current context.  This is applied to
  4126 specifications and theorems of the interpreted expression.
  4127 Interpretation in locales only permits parameter renaming through the
  4128 locale expression.  Interpretation is smart in that interpretations
  4129 that are active already do not occur in proof obligations, neither are
  4130 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4131 inspect active interpretations of a particular locale.  For details,
  4132 see the Isar Reference manual.  Examples can be found in
  4133 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4134 
  4135 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4136 'interpret' instead.
  4137 
  4138 * New context element 'constrains' for adding type constraints to
  4139 parameters.
  4140 
  4141 * Context expressions: renaming of parameters with syntax
  4142 redeclaration.
  4143 
  4144 * Locale declaration: 'includes' disallowed.
  4145 
  4146 * Proper static binding of attribute syntax -- i.e. types / terms /
  4147 facts mentioned as arguments are always those of the locale definition
  4148 context, independently of the context of later invocations.  Moreover,
  4149 locale operations (renaming and type / term instantiation) are applied
  4150 to attribute arguments as expected.
  4151 
  4152 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4153 actual attributes; rare situations may require Attrib.attribute to
  4154 embed those attributes into Attrib.src that lack concrete syntax.
  4155 Attribute implementations need to cooperate properly with the static
  4156 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4157 Attrib.XXX_thm etc. already do the right thing without further
  4158 intervention.  Only unusual applications -- such as "where" or "of"
  4159 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4160 on the context and the facts involved -- may have to assign parsed
  4161 values to argument tokens explicitly.
  4162 
  4163 * Changed parameter management in theorem generation for long goal
  4164 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4165 theorem statement in rare situations.
  4166 
  4167 * Locale inspection command 'print_locale' omits notes elements.  Use
  4168 'print_locale!' to have them included in the output.
  4169 
  4170 
  4171 *** Provers ***
  4172 
  4173 * Provers/hypsubst.ML: improved version of the subst method, for
  4174 single-step rewriting: it now works in bound variable contexts. New is
  4175 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4176 rewrite a different subterm than the original subst method, which is
  4177 still available as 'simplesubst'.
  4178 
  4179 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4180 and quasi orders.
  4181 
  4182 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4183 reflexive-transitive closure of relations.
  4184 
  4185 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4186 limit (previously hard-coded with a value of 20) user-definable.
  4187 
  4188 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4189 is peformed already.  Object-logics merely need to finish their
  4190 initial simpset configuration as before.  INCOMPATIBILITY.
  4191 
  4192 
  4193 *** HOL ***
  4194 
  4195 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4196 
  4197   syntax (epsilon)
  4198     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4199 
  4200 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4201 and x-symbol; use option '-m epsilon' to get it actually printed.
  4202 Moreover, the mathematically important symbolic identifier \<epsilon>
  4203 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4204 
  4205 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  4206 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  4207 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  4208 support corresponding Isar calculations.
  4209 
  4210 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  4211 instead of ":".
  4212 
  4213 * theory SetInterval: changed the syntax for open intervals:
  4214 
  4215   Old       New
  4216   {..n(}    {..<n}
  4217   {)n..}    {n<..}
  4218   {m..n(}   {m..<n}
  4219   {)m..n}   {m<..n}
  4220   {)m..n(}  {m<..<n}
  4221 
  4222 The old syntax is still supported but will disappear in the next
  4223 release.  For conversion use the following Emacs search and replace
  4224 patterns (these are not perfect but work quite well):
  4225 
  4226   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  4227   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  4228 
  4229 * Theory Commutative_Ring (in Library): method comm_ring for proving
  4230 equalities in commutative rings; method 'algebra' provides a generic
  4231 interface.
  4232 
  4233 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  4234 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  4235 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  4236 be a tuple pattern.
  4237 
  4238 Some new syntax forms are available:
  4239 
  4240   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  4241   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  4242   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  4243   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  4244 
  4245 The latter form "\<Sum>x < k. e" used to be based on a separate
  4246 function "Summation", which has been discontinued.
  4247 
  4248 * theory Finite_Set: in structured induction proofs, the insert case
  4249 is now 'case (insert x F)' instead of the old counterintuitive 'case
  4250 (insert F x)'.
  4251 
  4252 * The 'refute' command has been extended to support a much larger
  4253 fragment of HOL, including axiomatic type classes, constdefs and
  4254 typedefs, inductive datatypes and recursion.
  4255 
  4256 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  4257 Requires zChaff with proof generation to be installed.  See
  4258 HOL/ex/SAT_Examples.thy for examples.
  4259 
  4260 * Datatype induction via method 'induct' now preserves the name of the
  4261 induction variable. For example, when proving P(xs::'a list) by
  4262 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  4263 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  4264 in unstructured proof scripts.
  4265 
  4266 * Reworked implementation of records.  Improved scalability for
  4267 records with many fields, avoiding performance problems for type
  4268 inference. Records are no longer composed of nested field types, but
  4269 of nested extension types. Therefore the record type only grows linear
  4270 in the number of extensions and not in the number of fields.  The
  4271 top-level (users) view on records is preserved.  Potential
  4272 INCOMPATIBILITY only in strange cases, where the theory depends on the
  4273 old record representation. The type generated for a record is called
  4274 <record_name>_ext_type.
  4275 
  4276 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  4277 proofs triggered by a record definition or a simproc (if
  4278 quick_and_dirty is enabled).  Definitions of large records can take
  4279 quite long.
  4280 
  4281 New simproc record_upd_simproc for simplification of multiple record
  4282 updates enabled by default.  Moreover, trivial updates are also
  4283 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  4284 occasionally, since simplification is more powerful by default.
  4285 
  4286 * typedef: proper support for polymorphic sets, which contain extra
  4287 type-variables in the term.
  4288 
  4289 * Simplifier: automatically reasons about transitivity chains
  4290 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  4291 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  4292 old proofs break occasionally as simplification may now solve more
  4293 goals than previously.
  4294 
  4295 * Simplifier: converts x <= y into x = y if assumption y <= x is
  4296 present.  Works for all partial orders (class "order"), in particular
  4297 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  4298 just like y <= x.
  4299 
  4300 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  4301 bound variable or a constant then the let is unfolded.  Otherwise
  4302 first a is simplified to b, and then f b is simplified to g. If
  4303 possible we abstract b from g arriving at "let x = b in h x",
  4304 otherwise we unfold the let and arrive at g.  The simproc can be
  4305 enabled/disabled by the reference use_let_simproc.  Potential
  4306 INCOMPATIBILITY since simplification is more powerful by default.
  4307 
  4308 * Classical reasoning: the meson method now accepts theorems as arguments.
  4309 
  4310 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  4311 jobs to provide advice on the provability of subgoals.
  4312 
  4313 * Theory OrderedGroup and Ring_and_Field: various additions and
  4314 improvements to faciliate calculations involving equalities and
  4315 inequalities.
  4316 
  4317 The following theorems have been eliminated or modified
  4318 (INCOMPATIBILITY):
  4319 
  4320   abs_eq             now named abs_of_nonneg
  4321   abs_of_ge_0        now named abs_of_nonneg
  4322   abs_minus_eq       now named abs_of_nonpos
  4323   imp_abs_id         now named abs_of_nonneg
  4324   imp_abs_neg_id     now named abs_of_nonpos
  4325   mult_pos           now named mult_pos_pos
  4326   mult_pos_le        now named mult_nonneg_nonneg
  4327   mult_pos_neg_le    now named mult_nonneg_nonpos
  4328   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  4329   mult_neg           now named mult_neg_neg
  4330   mult_neg_le        now named mult_nonpos_nonpos
  4331 
  4332 * The following lemmas in Ring_and_Field have been added to the simplifier:
  4333      
  4334      zero_le_square
  4335      not_square_less_zero 
  4336 
  4337   The following lemmas have been deleted from Real/RealPow:
  4338   
  4339      realpow_zero_zero
  4340      realpow_two
  4341      realpow_less
  4342      zero_le_power
  4343      realpow_two_le
  4344      abs_realpow_two
  4345      realpow_two_abs     
  4346 
  4347 * Theory Parity: added rules for simplifying exponents.
  4348 
  4349 * Theory List:
  4350 
  4351 The following theorems have been eliminated or modified
  4352 (INCOMPATIBILITY):
  4353 
  4354   list_all_Nil       now named list_all.simps(1)
  4355   list_all_Cons      now named list_all.simps(2)
  4356   list_all_conv      now named list_all_iff
  4357   set_mem_eq         now named mem_iff
  4358 
  4359 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  4360 asymptotic "big O" calculations.  See the notes in BigO.thy.
  4361 
  4362 
  4363 *** HOL-Complex ***
  4364 
  4365 * Theory RealDef: better support for embedding natural numbers and
  4366 integers in the reals.
  4367 
  4368 The following theorems have been eliminated or modified
  4369 (INCOMPATIBILITY):
  4370 
  4371   exp_ge_add_one_self  now requires no hypotheses
  4372   real_of_int_add      reversed direction of equality (use [symmetric])
  4373   real_of_int_minus    reversed direction of equality (use [symmetric])
  4374   real_of_int_diff     reversed direction of equality (use [symmetric])
  4375   real_of_int_mult     reversed direction of equality (use [symmetric])
  4376 
  4377 * Theory RComplete: expanded support for floor and ceiling functions.
  4378 
  4379 * Theory Ln is new, with properties of the natural logarithm
  4380 
  4381 * Hyperreal: There is a new type constructor "star" for making
  4382 nonstandard types.  The old type names are now type synonyms:
  4383 
  4384   hypreal = real star
  4385   hypnat = nat star
  4386   hcomplex = complex star
  4387 
  4388 * Hyperreal: Many groups of similarly-defined constants have been
  4389 replaced by polymorphic versions (INCOMPATIBILITY):
  4390 
  4391   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  4392 
  4393   starset      <-- starsetNat, starsetC
  4394   *s*          <-- *sNat*, *sc*
  4395   starset_n    <-- starsetNat_n, starsetC_n
  4396   *sn*         <-- *sNatn*, *scn*
  4397   InternalSets <-- InternalNatSets, InternalCSets
  4398 
  4399   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  4400   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  4401   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  4402   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  4403   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  4404 
  4405 * Hyperreal: Many type-specific theorems have been removed in favor of
  4406 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  4407 
  4408   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  4409   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  4410   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  4411   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  4412   right_minus <-- hypreal_add_minus
  4413   left_minus <-- {hypreal,hcomplex}_add_minus_left
  4414   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  4415   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  4416   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  4417   mult_1_right <-- hcomplex_mult_one_right
  4418   mult_zero_left <-- hcomplex_mult_zero_left
  4419   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  4420   right_distrib <-- hypnat_add_mult_distrib2
  4421   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  4422   right_inverse <-- hypreal_mult_inverse
  4423   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  4424   order_refl <-- {hypreal,hypnat}_le_refl
  4425   order_trans <-- {hypreal,hypnat}_le_trans
  4426   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  4427   order_less_le <-- {hypreal,hypnat}_less_le
  4428   linorder_linear <-- {hypreal,hypnat}_le_linear
  4429   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  4430   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  4431   add_nonneg_nonneg <-- hypreal_le_add_order
  4432 
  4433 * Hyperreal: Separate theorems having to do with type-specific
  4434 versions of constants have been merged into theorems that apply to the
  4435 new polymorphic constants (INCOMPATIBILITY):
  4436 
  4437   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  4438   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  4439   STAR_Un <-- {STAR,NatStar,STARC}_Un
  4440   STAR_Int <-- {STAR,NatStar,STARC}_Int
  4441   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  4442   STAR_subset <-- {STAR,NatStar,STARC}_subset
  4443   STAR_mem <-- {STAR,NatStar,STARC}_mem
  4444   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  4445   STAR_diff <-- {STAR,STARC}_diff
  4446   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  4447     STARC_hcomplex_of_complex}_image_subset
  4448   starset_n_Un <-- starset{Nat,C}_n_Un
  4449   starset_n_Int <-- starset{Nat,C}_n_Int
  4450   starset_n_Compl <-- starset{Nat,C}_n_Compl
  4451   starset_n_diff <-- starset{Nat,C}_n_diff
  4452   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  4453   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  4454   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  4455   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  4456   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  4457   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  4458   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  4459   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  4460   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  4461   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  4462   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  4463   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  4464   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  4465   starfun_diff <-- starfun{C,RC,CR}_diff
  4466   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  4467   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  4468   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  4469   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  4470   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  4471   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  4472   starfun_Id <-- starfunC_Id
  4473   starfun_approx <-- starfun{Nat,CR}_approx
  4474   starfun_capprox <-- starfun{C,RC}_capprox
  4475   starfun_abs <-- starfunNat_rabs
  4476   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  4477   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  4478   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  4479   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  4480   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  4481   starfun_add_approx <-- starfunCR_add_approx
  4482   starfun_inverse_inverse <-- starfunC_inverse_inverse
  4483   starfun_divide <-- starfun{C,CR,RC}_divide
  4484   starfun_n <-- starfun{Nat,C}_n
  4485   starfun_n_mult <-- starfun{Nat,C}_n_mult
  4486   starfun_n_add <-- starfun{Nat,C}_n_add
  4487   starfun_n_add_minus <-- starfunNat_n_add_minus
  4488   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  4489   starfun_n_minus <-- starfun{Nat,C}_n_minus
  4490   starfun_n_eq <-- starfun{Nat,C}_n_eq
  4491 
  4492   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  4493   star_n_minus <-- {hypreal,hcomplex}_minus
  4494   star_n_diff <-- {hypreal,hcomplex}_diff
  4495   star_n_mult <-- {hypreal,hcomplex}_mult
  4496   star_n_inverse <-- {hypreal,hcomplex}_inverse
  4497   star_n_le <-- {hypreal,hypnat}_le
  4498   star_n_less <-- {hypreal,hypnat}_less
  4499   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  4500   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  4501   star_n_abs <-- hypreal_hrabs
  4502   star_n_divide <-- hcomplex_divide
  4503 
  4504   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  4505   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  4506   star_of_diff <-- hypreal_of_real_diff
  4507   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  4508   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  4509   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  4510   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  4511   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  4512   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  4513   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  4514   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  4515   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  4516   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  4517   star_of_number_of <-- {hypreal,hcomplex}_number_of
  4518   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  4519   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  4520   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  4521   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  4522   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  4523   star_of_power <-- hypreal_of_real_power
  4524   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  4525 
  4526 * Hyperreal: new method "transfer" that implements the transfer
  4527 principle of nonstandard analysis. With a subgoal that mentions
  4528 nonstandard types like "'a star", the command "apply transfer"
  4529 replaces it with an equivalent one that mentions only standard types.
  4530 To be successful, all free variables must have standard types; non-
  4531 standard variables must have explicit universal quantifiers.
  4532 
  4533 * Hyperreal: A theory of Taylor series.
  4534 
  4535 
  4536 *** HOLCF ***
  4537 
  4538 * Discontinued special version of 'constdefs' (which used to support
  4539 continuous functions) in favor of the general Pure one with full
  4540 type-inference.
  4541 
  4542 * New simplification procedure for solving continuity conditions; it
  4543 is much faster on terms with many nested lambda abstractions (cubic
  4544 instead of exponential time).
  4545 
  4546 * New syntax for domain package: selector names are now optional.
  4547 Parentheses should be omitted unless argument is lazy, for example:
  4548 
  4549   domain 'a stream = cons "'a" (lazy "'a stream")
  4550 
  4551 * New command 'fixrec' for defining recursive functions with pattern
  4552 matching; defining multiple functions with mutual recursion is also
  4553 supported.  Patterns may include the constants cpair, spair, up, sinl,
  4554 sinr, or any data constructor defined by the domain package. The given
  4555 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  4556 syntax and examples.
  4557 
  4558 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  4559 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  4560 but the proof obligation additionally includes an admissibility
  4561 requirement. The packages generate instances of class cpo or pcpo,
  4562 with continuity and strictness theorems for Rep and Abs.
  4563 
  4564 * HOLCF: Many theorems have been renamed according to a more standard naming
  4565 scheme (INCOMPATIBILITY):
  4566 
  4567   foo_inject:  "foo$x = foo$y ==> x = y"
  4568   foo_eq:      "(foo$x = foo$y) = (x = y)"
  4569   foo_less:    "(foo$x << foo$y) = (x << y)"
  4570   foo_strict:  "foo$UU = UU"
  4571   foo_defined: "... ==> foo$x ~= UU"
  4572   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  4573 
  4574 
  4575 *** ZF ***
  4576 
  4577 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  4578 including the First Isomorphism Theorem (on quotienting by the kernel
  4579 of a homomorphism).
  4580 
  4581 * ZF/Simplifier: install second copy of type solver that actually
  4582 makes use of TC rules declared to Isar proof contexts (or locales);
  4583 the old version is still required for ML proof scripts.
  4584 
  4585 
  4586 *** Cube ***
  4587 
  4588 * Converted to Isar theory format; use locales instead of axiomatic
  4589 theories.
  4590 
  4591 
  4592 *** ML ***
  4593 
  4594 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  4595 for ||>, ||>>, |>>,
  4596 
  4597 * Pure/library.ML no longer defines its own option datatype, but uses
  4598 that of the SML basis, which has constructors NONE and SOME instead of
  4599 None and Some, as well as exception Option.Option instead of OPTION.
  4600 The functions the, if_none, is_some, is_none have been adapted
  4601 accordingly, while Option.map replaces apsome.
  4602 
  4603 * Pure/library.ML: the exception LIST has been given up in favour of
  4604 the standard exceptions Empty and Subscript, as well as
  4605 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  4606 superceded by the standard hd and tl functions etc.
  4607 
  4608 A number of basic list functions are no longer exported to the ML
  4609 toplevel, as they are variants of predefined functions.  The following
  4610 suggests how one can translate existing code:
  4611 
  4612     rev_append xs ys = List.revAppend (xs, ys)
  4613     nth_elem (i, xs) = List.nth (xs, i)
  4614     last_elem xs = List.last xs
  4615     flat xss = List.concat xss
  4616     seq fs = List.app fs
  4617     partition P xs = List.partition P xs
  4618     mapfilter f xs = List.mapPartial f xs
  4619 
  4620 * Pure/library.ML: several combinators for linear functional
  4621 transformations, notably reverse application and composition:
  4622 
  4623   x |> f                f #> g
  4624   (x, y) |-> f          f #-> g
  4625 
  4626 * Pure/library.ML: introduced/changed precedence of infix operators:
  4627 
  4628   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  4629   infix 2 ?;
  4630   infix 3 o oo ooo oooo;
  4631   infix 4 ~~ upto downto;
  4632 
  4633 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  4634 infix operators.
  4635 
  4636 * Pure/library.ML: natural list combinators fold, fold_rev, and
  4637 fold_map support linear functional transformations and nesting.  For
  4638 example:
  4639 
  4640   fold f [x1, ..., xN] y =
  4641     y |> f x1 |> ... |> f xN
  4642 
  4643   (fold o fold) f [xs1, ..., xsN] y =
  4644     y |> fold f xs1 |> ... |> fold f xsN
  4645 
  4646   fold f [x1, ..., xN] =
  4647     f x1 #> ... #> f xN
  4648 
  4649   (fold o fold) f [xs1, ..., xsN] =
  4650     fold f xs1 #> ... #> fold f xsN
  4651 
  4652 * Pure/library.ML: the following selectors on type 'a option are
  4653 available:
  4654 
  4655   the:               'a option -> 'a  (*partial*)
  4656   these:             'a option -> 'a  where 'a = 'b list
  4657   the_default: 'a -> 'a option -> 'a
  4658   the_list:          'a option -> 'a list
  4659 
  4660 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  4661 basic operations for association lists, following natural argument
  4662 order; moreover the explicit equality predicate passed here avoids
  4663 potentially expensive polymorphic runtime equality checks.
  4664 The old functions may be expressed as follows:
  4665 
  4666   assoc = uncurry (AList.lookup (op =))
  4667   assocs = these oo AList.lookup (op =)
  4668   overwrite = uncurry (AList.update (op =)) o swap
  4669 
  4670 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  4671 
  4672   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  4673   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  4674 
  4675 replacing make_keylist and keyfilter (occassionally used)
  4676 Naive rewrites:
  4677 
  4678   make_keylist = AList.make
  4679   keyfilter = AList.find (op =)
  4680 
  4681 * eq_fst and eq_snd now take explicit equality parameter, thus
  4682   avoiding eqtypes. Naive rewrites:
  4683 
  4684     eq_fst = eq_fst (op =)
  4685     eq_snd = eq_snd (op =)
  4686 
  4687 * Removed deprecated apl and apr (rarely used).
  4688   Naive rewrites:
  4689 
  4690     apl (n, op) =>>= curry op n
  4691     apr (op, m) =>>= fn n => op (n, m)
  4692 
  4693 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  4694 provides a reasonably efficient light-weight implementation of sets as
  4695 lists.
  4696 
  4697 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  4698 few new operations; existing lookup and update are now curried to
  4699 follow natural argument order (for use with fold etc.);
  4700 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  4701 
  4702 * Pure/General: output via the Isabelle channels of
  4703 writeln/warning/error etc. is now passed through Output.output, with a
  4704 hook for arbitrary transformations depending on the print_mode
  4705 (cf. Output.add_mode -- the first active mode that provides a output
  4706 function wins).  Already formatted output may be embedded into further
  4707 text via Output.raw; the result of Pretty.string_of/str_of and derived
  4708 functions (string_of_term/cterm/thm etc.) is already marked raw to
  4709 accommodate easy composition of diagnostic messages etc.  Programmers
  4710 rarely need to care about Output.output or Output.raw at all, with
  4711 some notable exceptions: Output.output is required when bypassing the
  4712 standard channels (writeln etc.), or in token translations to produce
  4713 properly formatted results; Output.raw is required when capturing
  4714 already output material that will eventually be presented to the user
  4715 a second time.  For the default print mode, both Output.output and
  4716 Output.raw have no effect.
  4717 
  4718 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  4719 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  4720 cumulative results are displayed at the end of a batch session.
  4721 
  4722 * Pure/General: File.sysify_path and File.quote_sysify path have been
  4723 replaced by File.platform_path and File.shell_path (with appropriate
  4724 hooks).  This provides a clean interface for unusual systems where the
  4725 internal and external process view of file names are different.
  4726 
  4727 * Pure: more efficient orders for basic syntactic entities: added
  4728 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  4729 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  4730 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  4731 orders now -- potential INCOMPATIBILITY for code that depends on a
  4732 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  4733 Library.sort_strings on result).
  4734 
  4735 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  4736 fold_types traverse types/terms from left to right, observing natural
  4737 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  4738 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  4739 
  4740 * Pure: name spaces have been refined, with significant changes of the
  4741 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  4742 to extern(_table).  The plain name entry path is superceded by a
  4743 general 'naming' context, which also includes the 'policy' to produce
  4744 a fully qualified name and external accesses of a fully qualified
  4745 name; NameSpace.extend is superceded by context dependent
  4746 Sign.declare_name.  Several theory and proof context operations modify
  4747 the naming context.  Especially note Theory.restore_naming and
  4748 ProofContext.restore_naming to get back to a sane state; note that
  4749 Theory.add_path is no longer sufficient to recover from
  4750 Theory.absolute_path in particular.
  4751 
  4752 * Pure: new flags short_names (default false) and unique_names
  4753 (default true) for controlling output of qualified names.  If
  4754 short_names is set, names are printed unqualified.  If unique_names is
  4755 reset, the name prefix is reduced to the minimum required to achieve
  4756 the original result when interning again, even if there is an overlap
  4757 with earlier declarations.
  4758 
  4759 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  4760 now 'extend', and 'merge' gets an additional Pretty.pp argument
  4761 (useful for printing error messages).  INCOMPATIBILITY.
  4762 
  4763 * Pure: major reorganization of the theory context.  Type Sign.sg and
  4764 Theory.theory are now identified, referring to the universal
  4765 Context.theory (see Pure/context.ML).  Actual signature and theory
  4766 content is managed as theory data.  The old code and interfaces were
  4767 spread over many files and structures; the new arrangement introduces
  4768 considerable INCOMPATIBILITY to gain more clarity:
  4769 
  4770   Context -- theory management operations (name, identity, inclusion,
  4771     parents, ancestors, merge, etc.), plus generic theory data;
  4772 
  4773   Sign -- logical signature and syntax operations (declaring consts,
  4774     types, etc.), plus certify/read for common entities;
  4775 
  4776   Theory -- logical theory operations (stating axioms, definitions,
  4777     oracles), plus a copy of logical signature operations (consts,
  4778     types, etc.); also a few basic management operations (Theory.copy,
  4779     Theory.merge, etc.)
  4780 
  4781 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  4782 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  4783 for convenience -- they merely return the theory.
  4784 
  4785 * Pure: type Type.tsig is superceded by theory in most interfaces.
  4786 
  4787 * Pure: the Isar proof context type is already defined early in Pure
  4788 as Context.proof (note that ProofContext.context and Proof.context are
  4789 aliases, where the latter is the preferred name).  This enables other
  4790 Isabelle components to refer to that type even before Isar is present.
  4791 
  4792 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  4793 typeK, constK, axiomK, oracleK), but provide explicit operations for
  4794 any of these kinds.  For example, Sign.intern typeK is now
  4795 Sign.intern_type, Theory.hide_space Sign.typeK is now
  4796 Theory.hide_types.  Also note that former
  4797 Theory.hide_classes/types/consts are now
  4798 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  4799 internalize their arguments!  INCOMPATIBILITY.
  4800 
  4801 * Pure: get_thm interface (of PureThy and ProofContext) expects
  4802 datatype thmref (with constructors Name and NameSelection) instead of
  4803 plain string -- INCOMPATIBILITY;
  4804 
  4805 * Pure: cases produced by proof methods specify options, where NONE
  4806 means to remove case bindings -- INCOMPATIBILITY in
  4807 (RAW_)METHOD_CASES.
  4808 
  4809 * Pure: the following operations retrieve axioms or theorems from a
  4810 theory node or theory hierarchy, respectively:
  4811 
  4812   Theory.axioms_of: theory -> (string * term) list
  4813   Theory.all_axioms_of: theory -> (string * term) list
  4814   PureThy.thms_of: theory -> (string * thm) list
  4815   PureThy.all_thms_of: theory -> (string * thm) list
  4816 
  4817 * Pure: print_tac now outputs the goal through the trace channel.
  4818 
  4819 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  4820 Reference Toplevel.debug (default false) controls detailed printing
  4821 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  4822 controls execution profiling -- set to 1 for time and 2 for space
  4823 (both increase the runtime).
  4824 
  4825 * Isar session: The initial use of ROOT.ML is now always timed,
  4826 i.e. the log will show the actual process times, in contrast to the
  4827 elapsed wall-clock time that the outer shell wrapper produces.
  4828 
  4829 * Simplifier: improved handling of bound variables (nameless
  4830 representation, avoid allocating new strings).  Simprocs that invoke
  4831 the Simplifier recursively should use Simplifier.inherit_bounds to
  4832 avoid local name clashes.  Failure to do so produces warnings
  4833 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  4834 for further details.
  4835 
  4836 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  4837 bindings for all theorems stored within a given theory; this may help
  4838 in porting non-Isar theories to Isar ones, while keeping ML proof
  4839 scripts for the time being.
  4840 
  4841 * ML operator HTML.with_charset specifies the charset begin used for
  4842 generated HTML files.  For example:
  4843 
  4844   HTML.with_charset "utf-8" use_thy "Hebrew";
  4845   HTML.with_charset "utf-8" use_thy "Chinese";
  4846 
  4847 
  4848 *** System ***
  4849 
  4850 * Allow symlinks to all proper Isabelle executables (Isabelle,
  4851 isabelle, isatool etc.).
  4852 
  4853 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  4854 isatool doc, isatool mkdir, display_drafts etc.).
  4855 
  4856 * isatool usedir: option -f allows specification of the ML file to be
  4857 used by Isabelle; default is ROOT.ML.
  4858 
  4859 * New isatool version outputs the version identifier of the Isabelle
  4860 distribution being used.
  4861 
  4862 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  4863 (containing Boolean satisfiability problems) into Isabelle/HOL
  4864 theories.
  4865 
  4866 
  4867 
  4868 New in Isabelle2004 (April 2004)
  4869 --------------------------------
  4870 
  4871 *** General ***
  4872 
  4873 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  4874   Replaces linorder.ML.
  4875 
  4876 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  4877   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  4878   (\<a>...\<z>), are now considered normal letters, and can therefore
  4879   be used anywhere where an ASCII letter (a...zA...Z) has until
  4880   now. COMPATIBILITY: This obviously changes the parsing of some
  4881   terms, especially where a symbol has been used as a binder, say
  4882   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  4883   as an identifier.  Fix it by inserting a space around former
  4884   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  4885   existing theory and ML files.
  4886 
  4887 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  4888 
  4889 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  4890   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  4891   a normal (but invisible) letter. For multiple letter subscripts repeat
  4892   \<^isub> like this: x\<^isub>1\<^isub>2.
  4893 
  4894 * Pure: There are now sub-/superscripts that can span more than one
  4895   character. Text between \<^bsub> and \<^esub> is set in subscript in
  4896   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  4897   superscript. The new control characters are not identifier parts.
  4898 
  4899 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  4900   content of "..." to the latex file instead of \isacntrl... . The "..."
  4901   may consist of any printable characters excluding the end bracket >.
  4902 
  4903 * Pure: Using new Isar command "finalconsts" (or the ML functions
  4904   Theory.add_finals or Theory.add_finals_i) it is now possible to
  4905   declare constants "final", which prevents their being given a definition
  4906   later.  It is useful for constants whose behaviour is fixed axiomatically
  4907   rather than definitionally, such as the meta-logic connectives.
  4908 
  4909 * Pure: 'instance' now handles general arities with general sorts
  4910   (i.e. intersections of classes),
  4911 
  4912 * Presentation: generated HTML now uses a CSS style sheet to make layout
  4913   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  4914   It can be changed to alter the colors/layout of generated pages.
  4915 
  4916 
  4917 *** Isar ***
  4918 
  4919 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  4920   cut_tac, subgoal_tac and thin_tac:
  4921   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  4922     locales are no longer forced to write Isar proof scripts.
  4923     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  4924     emulations.
  4925   - INCOMPATIBILITY: names of variables to be instantiated may no
  4926     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  4927     This is consistent with the instantiation attribute "where".
  4928 
  4929 * Attributes "where" and "of":
  4930   - Now take type variables of instantiated theorem into account when reading
  4931     the instantiation string.  This fixes a bug that caused instantiated
  4932     theorems to have too special types in some circumstances.
  4933   - "where" permits explicit instantiations of type variables.
  4934 
  4935 * Calculation commands "moreover" and "also" no longer interfere with
  4936   current facts ("this"), admitting arbitrary combinations with "then"
  4937   and derived forms.
  4938 
  4939 * Locales:
  4940   - Goal statements involving the context element "includes" no longer
  4941     generate theorems with internal delta predicates (those ending on
  4942     "_axioms") in the premise.
  4943     Resolve particular premise with <locale>.intro to obtain old form.
  4944   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  4945     specification and "includes" elements in goal statement.
  4946   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  4947     [intro?] and [elim?] (respectively) by default.
  4948   - Experimental command for instantiation of locales in proof contexts:
  4949         instantiate <label>[<attrs>]: <loc>
  4950     Instantiates locale <loc> and adds all its theorems to the current context
  4951     taking into account their attributes.  Label and attrs are optional
  4952     modifiers, like in theorem declarations.  If present, names of
  4953     instantiated theorems are qualified with <label>, and the attributes
  4954     <attrs> are applied after any attributes these theorems might have already.
  4955       If the locale has assumptions, a chained fact of the form
  4956     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  4957     are derived.  The command does not support old-style locales declared
  4958     with "locale (open)".
  4959       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  4960 
  4961 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  4962   (Isar) contexts.
  4963 
  4964 
  4965 *** HOL ***
  4966 
  4967 * Proof import: new image HOL4 contains the imported library from
  4968   the HOL4 system with about 2500 theorems. It is imported by
  4969   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  4970   can be used like any other Isabelle image.  See
  4971   HOL/Import/HOL/README for more information.
  4972 
  4973 * Simplifier:
  4974   - Much improved handling of linear and partial orders.
  4975     Reasoners for linear and partial orders are set up for type classes
  4976     "linorder" and "order" respectively, and are added to the default simpset
  4977     as solvers.  This means that the simplifier can build transitivity chains
  4978     to solve goals from the assumptions.
  4979   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  4980     of blast or auto after simplification become unnecessary because the goal
  4981     is solved by simplification already.
  4982 
  4983 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  4984     all proved in axiomatic type classes for semirings, rings and fields.
  4985 
  4986 * Numerics:
  4987   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  4988     now formalized using the Ring_and_Field theory mentioned above.
  4989   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  4990     than before, because now they are set up once in a generic manner.
  4991   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  4992     Look for the general versions in Ring_and_Field (and Power if they concern
  4993     exponentiation).
  4994 
  4995 * Type "rat" of the rational numbers is now available in HOL-Complex.
  4996 
  4997 * Records:
  4998   - Record types are now by default printed with their type abbreviation
  4999     instead of the list of all field types. This can be configured via
  5000     the reference "print_record_type_abbr".
  5001   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5002     (not enabled by default).
  5003   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5004     EX x. x = sel r to True (not enabled by default).
  5005   - Tactic "record_split_simp_tac" to split and simplify records added.
  5006 
  5007 * 'specification' command added, allowing for definition by
  5008   specification.  There is also an 'ax_specification' command that
  5009   introduces the new constants axiomatically.
  5010 
  5011 * arith(_tac) is now able to generate counterexamples for reals as well.
  5012 
  5013 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5014 
  5015 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5016   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5017 
  5018 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5019   matrix theory to linear programming.
  5020 
  5021 * Unions and Intersections:
  5022   The latex output syntax of UN and INT has been changed
  5023   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5024   i.e. the index formulae has become a subscript.
  5025   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5026 
  5027 * Unions and Intersections over Intervals:
  5028   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5029   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5030   like in normal math, and corresponding versions for < and for intersection.
  5031 
  5032 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5033   lexicographic dictonary ordering has been added as "lexord".
  5034 
  5035 * ML: the legacy theory structures Int and List have been removed. They had
  5036   conflicted with ML Basis Library structures having the same names.
  5037 
  5038 * 'refute' command added to search for (finite) countermodels.  Only works
  5039   for a fragment of HOL.  The installation of an external SAT solver is
  5040   highly recommended.  See "HOL/Refute.thy" for details.
  5041 
  5042 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5043   formulae under an assignment of free variables to random values.
  5044   In contrast to 'refute', it can deal with inductive datatypes,
  5045   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5046   for examples.
  5047 
  5048 
  5049 *** HOLCF ***
  5050 
  5051 * Streams now come with concatenation and are part of the HOLCF image
  5052 
  5053 
  5054 
  5055 New in Isabelle2003 (May 2003)
  5056 ------------------------------
  5057 
  5058 *** General ***
  5059 
  5060 * Provers/simplifier:
  5061 
  5062   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5063     Assumptions are now subject to complete mutual simplification,
  5064     not just from left to right. The simplifier now preserves
  5065     the order of assumptions.
  5066 
  5067     Potential INCOMPATIBILITY:
  5068 
  5069     -- simp sometimes diverges where the old version did
  5070        not, e.g. invoking simp on the goal
  5071 
  5072         [| P (f x); y = x; f x = f y |] ==> Q
  5073 
  5074        now gives rise to the infinite reduction sequence
  5075 
  5076         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5077 
  5078        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5079        kind of problem.
  5080 
  5081     -- Tactics combining classical reasoner and simplification (such as auto)
  5082        are also affected by this change, because many of them rely on
  5083        simp. They may sometimes diverge as well or yield a different numbers
  5084        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5085        in case of problems. Sometimes subsequent calls to the classical
  5086        reasoner will fail because a preceeding call to the simplifier too
  5087        eagerly simplified the goal, e.g. deleted redundant premises.
  5088 
  5089   - The simplifier trace now shows the names of the applied rewrite rules
  5090 
  5091   - You can limit the number of recursive invocations of the simplifier
  5092     during conditional rewriting (where the simplifie tries to solve the
  5093     conditions before applying the rewrite rule):
  5094     ML "simp_depth_limit := n"
  5095     where n is an integer. Thus you can force termination where previously
  5096     the simplifier would diverge.
  5097 
  5098   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5099 
  5100   - No longer aborts on failed congruence proof.  Instead, the
  5101     congruence is ignored.
  5102 
  5103 * Pure: New generic framework for extracting programs from constructive
  5104   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5105   as HOL/Extraction for some case studies.
  5106 
  5107 * Pure: The main goal of the proof state is no longer shown by default, only
  5108 the subgoals. This behaviour is controlled by a new flag.
  5109    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5110 (ML: Proof.show_main_goal).
  5111 
  5112 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5113 rules whose conclusion matches subgoal 1:
  5114       PG menu: Isabelle/Isar -> Show me -> matching rules
  5115 The rules are ordered by how closely they match the subgoal.
  5116 In particular, rules that solve a subgoal outright are displayed first
  5117 (or rather last, the way they are printed).
  5118 (ML: ProofGeneral.print_intros())
  5119 
  5120 * Pure: New flag trace_unify_fail causes unification to print
  5121 diagnostic information (PG: in trace buffer) when it fails. This is
  5122 useful for figuring out why single step proofs like rule, erule or
  5123 assumption failed.
  5124 
  5125 * Pure: Locale specifications now produce predicate definitions
  5126 according to the body of text (covering assumptions modulo local
  5127 definitions); predicate "loc_axioms" covers newly introduced text,
  5128 while "loc" is cumulative wrt. all included locale expressions; the
  5129 latter view is presented only on export into the global theory
  5130 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5131 on the old view without predicates;
  5132 
  5133 * Pure: predefined locales "var" and "struct" are useful for sharing
  5134 parameters (as in CASL, for example); just specify something like
  5135 ``var x + var y + struct M'' as import;
  5136 
  5137 * Pure: improved thms_containing: proper indexing of facts instead of
  5138 raw theorems; check validity of results wrt. current name space;
  5139 include local facts of proof configuration (also covers active
  5140 locales), cover fixed variables in index; may use "_" in term
  5141 specification; an optional limit for the number of printed facts may
  5142 be given (the default is 40);
  5143 
  5144 * Pure: disallow duplicate fact bindings within new-style theory files
  5145 (batch-mode only);
  5146 
  5147 * Provers: improved induct method: assumptions introduced by case
  5148 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5149 the goal statement); "foo" still refers to all facts collectively;
  5150 
  5151 * Provers: the function blast.overloaded has been removed: all constants
  5152 are regarded as potentially overloaded, which improves robustness in exchange
  5153 for slight decrease in efficiency;
  5154 
  5155 * Provers/linorder: New generic prover for transitivity reasoning over
  5156 linear orders.  Note: this prover is not efficient!
  5157 
  5158 * Isar: preview of problems to finish 'show' now produce an error
  5159 rather than just a warning (in interactive mode);
  5160 
  5161 
  5162 *** HOL ***
  5163 
  5164 * arith(_tac)
  5165 
  5166  - Produces a counter example if it cannot prove a goal.
  5167    Note that the counter example may be spurious if the goal is not a formula
  5168    of quantifier-free linear arithmetic.
  5169    In ProofGeneral the counter example appears in the trace buffer.
  5170 
  5171  - Knows about div k and mod k where k is a numeral of type nat or int.
  5172 
  5173  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5174    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5175    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5176 
  5177 * simp's arithmetic capabilities have been enhanced a bit: it now
  5178 takes ~= in premises into account (by performing a case split);
  5179 
  5180 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5181 are distributed over a sum of terms;
  5182 
  5183 * New tactic "trans_tac" and method "trans" instantiate
  5184 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5185 "<=", "<" and "=").
  5186 
  5187 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5188 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5189 
  5190 * 'typedef' command has new option "open" to suppress the set
  5191 definition;
  5192 
  5193 * functions Min and Max on finite sets have been introduced (theory
  5194 Finite_Set);
  5195 
  5196 * attribute [symmetric] now works for relations as well; it turns
  5197 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5198 
  5199 * induct over a !!-quantified statement (say !!x1..xn):
  5200   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5201 
  5202 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5203 %x. None. Warning: empty_def now refers to the previously hidden definition
  5204 of the empty set.
  5205 
  5206 * Algebra: formalization of classical algebra.  Intended as base for
  5207 any algebraic development in Isabelle.  Currently covers group theory
  5208 (up to Sylow's theorem) and ring theory (Universal Property of
  5209 Univariate Polynomials).  Contributions welcome;
  5210 
  5211 * GroupTheory: deleted, since its material has been moved to Algebra;
  5212 
  5213 * Complex: new directory of the complex numbers with numeric constants,
  5214 nonstandard complex numbers, and some complex analysis, standard and
  5215 nonstandard (Jacques Fleuriot);
  5216 
  5217 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  5218 
  5219 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  5220 Fleuriot);
  5221 
  5222 * Real/HahnBanach: updated and adapted to locales;
  5223 
  5224 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  5225 Gray and Kramer);
  5226 
  5227 * UNITY: added the Meier-Sanders theory of progress sets;
  5228 
  5229 * MicroJava: bytecode verifier and lightweight bytecode verifier
  5230 as abstract algorithms, instantiated to the JVM;
  5231 
  5232 * Bali: Java source language formalization. Type system, operational
  5233 semantics, axiomatic semantics. Supported language features:
  5234 classes, interfaces, objects,virtual methods, static methods,
  5235 static/instance fields, arrays, access modifiers, definite
  5236 assignment, exceptions.
  5237 
  5238 
  5239 *** ZF ***
  5240 
  5241 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  5242 universe, etc.);
  5243 
  5244 * Main ZF: virtually all theories converted to new-style format;
  5245 
  5246 
  5247 *** ML ***
  5248 
  5249 * Pure: Tactic.prove provides sane interface for internal proofs;
  5250 omits the infamous "standard" operation, so this is more appropriate
  5251 than prove_goalw_cterm in many situations (e.g. in simprocs);
  5252 
  5253 * Pure: improved error reporting of simprocs;
  5254 
  5255 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  5256 up simprocs;
  5257 
  5258 
  5259 *** Document preparation ***
  5260 
  5261 * uses \par instead of \\ for line breaks in theory text. This may
  5262 shift some page breaks in large documents. To get the old behaviour
  5263 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  5264 
  5265 * minimized dependencies of isabelle.sty and isabellesym.sty on
  5266 other packages
  5267 
  5268 * \<euro> now needs package babel/greek instead of marvosym (which
  5269 broke \Rightarrow)
  5270 
  5271 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  5272 textcomp package)
  5273 
  5274 
  5275 
  5276 New in Isabelle2002 (March 2002)
  5277 --------------------------------
  5278 
  5279 *** Document preparation ***
  5280 
  5281 * greatly simplified document preparation setup, including more
  5282 graceful interpretation of isatool usedir -i/-d/-D options, and more
  5283 instructive isatool mkdir; users should basically be able to get
  5284 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  5285 users may run a separate document processing stage manually like this:
  5286 "isatool usedir -D output HOL Test && isatool document Test/output";
  5287 
  5288 * theory dependency graph may now be incorporated into documents;
  5289 isatool usedir -g true will produce session_graph.eps/.pdf for use
  5290 with \includegraphics of LaTeX;
  5291 
  5292 * proper spacing of consecutive markup elements, especially text
  5293 blocks after section headings;
  5294 
  5295 * support bold style (for single symbols only), input syntax is like
  5296 this: "\<^bold>\<alpha>" or "\<^bold>A";
  5297 
  5298 * \<bullet> is now output as bold \cdot by default, which looks much
  5299 better in printed text;
  5300 
  5301 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  5302 note that these symbols are currently unavailable in Proof General /
  5303 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  5304 
  5305 * isatool latex no longer depends on changed TEXINPUTS, instead
  5306 isatool document copies the Isabelle style files to the target
  5307 location;
  5308 
  5309 
  5310 *** Isar ***
  5311 
  5312 * Pure/Provers: improved proof by cases and induction;
  5313   - 'case' command admits impromptu naming of parameters (such as
  5314     "case (Suc n)");
  5315   - 'induct' method divinates rule instantiation from the inductive
  5316     claim; no longer requires excessive ?P bindings for proper
  5317     instantiation of cases;
  5318   - 'induct' method properly enumerates all possibilities of set/type
  5319     rules; as a consequence facts may be also passed through *type*
  5320     rules without further ado;
  5321   - 'induct' method now derives symbolic cases from the *rulified*
  5322     rule (before it used to rulify cases stemming from the internal
  5323     atomized version); this means that the context of a non-atomic
  5324     statement becomes is included in the hypothesis, avoiding the
  5325     slightly cumbersome show "PROP ?case" form;
  5326   - 'induct' may now use elim-style induction rules without chaining
  5327     facts, using ``missing'' premises from the goal state; this allows
  5328     rules stemming from inductive sets to be applied in unstructured
  5329     scripts, while still benefitting from proper handling of non-atomic
  5330     statements; NB: major inductive premises need to be put first, all
  5331     the rest of the goal is passed through the induction;
  5332   - 'induct' proper support for mutual induction involving non-atomic
  5333     rule statements (uses the new concept of simultaneous goals, see
  5334     below);
  5335   - append all possible rule selections, but only use the first
  5336     success (no backtracking);
  5337   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  5338   - undeclared rule case names default to numbers 1, 2, 3, ...;
  5339   - added 'print_induct_rules' (covered by help item in recent Proof
  5340     General versions);
  5341   - moved induct/cases attributes to Pure, methods to Provers;
  5342   - generic method setup instantiated for FOL and HOL;
  5343 
  5344 * Pure: support multiple simultaneous goal statements, for example
  5345 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  5346 meta-level mechanism, this acts as if several individual goals had
  5347 been stated separately; in particular common proof methods need to be
  5348 repeated in order to cover all claims; note that a single elimination
  5349 step is *not* sufficient to establish the two conjunctions, so this
  5350 fails:
  5351 
  5352   assume "A & B" then have A and B ..   (*".." fails*)
  5353 
  5354 better use "obtain" in situations as above; alternative refer to
  5355 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  5356 
  5357 * Pure: proper integration with ``locales''; unlike the original
  5358 version by Florian Kammller, Isar locales package high-level proof
  5359 contexts rather than raw logical ones (e.g. we admit to include
  5360 attributes everywhere); operations on locales include merge and
  5361 rename; support for implicit arguments (``structures''); simultaneous
  5362 type-inference over imports and text; see also HOL/ex/Locales.thy for
  5363 some examples;
  5364 
  5365 * Pure: the following commands have been ``localized'', supporting a
  5366 target locale specification "(in name)": 'lemma', 'theorem',
  5367 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  5368 stored both within the locale and at the theory level (exported and
  5369 qualified by the locale name);
  5370 
  5371 * Pure: theory goals may now be specified in ``long'' form, with
  5372 ad-hoc contexts consisting of arbitrary locale elements. for example
  5373 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  5374 definitions may be given, too); the result is a meta-level rule with
  5375 the context elements being discharged in the obvious way;
  5376 
  5377 * Pure: new proof command 'using' allows to augment currently used
  5378 facts after a goal statement ('using' is syntactically analogous to
  5379 'apply', but acts on the goal's facts only); this allows chained facts
  5380 to be separated into parts given before and after a claim, as in
  5381 ``from a and b have C using d and e <proof>'';
  5382 
  5383 * Pure: renamed "antecedent" case to "rule_context";
  5384 
  5385 * Pure: new 'judgment' command records explicit information about the
  5386 object-logic embedding (used by several tools internally); no longer
  5387 use hard-wired "Trueprop";
  5388 
  5389 * Pure: added 'corollary' command;
  5390 
  5391 * Pure: fixed 'token_translation' command;
  5392 
  5393 * Pure: removed obsolete 'exported' attribute;
  5394 
  5395 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  5396 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  5397 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  5398 
  5399 * Pure: method 'atomize' presents local goal premises as object-level
  5400 statements (atomic meta-level propositions); setup controlled via
  5401 rewrite rules declarations of 'atomize' attribute; example
  5402 application: 'induct' method with proper rule statements in improper
  5403 proof *scripts*;
  5404 
  5405 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  5406 now consider the syntactic context of assumptions, giving a better
  5407 chance to get type-inference of the arguments right (this is
  5408 especially important for locales);
  5409 
  5410 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  5411 mode;
  5412 
  5413 * Pure/obtain: the formal conclusion "thesis", being marked as
  5414 ``internal'', may no longer be reference directly in the text;
  5415 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  5416 situations;
  5417 
  5418 * Pure: generic 'sym' attribute which declares a rule both as pure
  5419 'elim?' and for the 'symmetric' operation;
  5420 
  5421 * Pure: marginal comments ``--'' may now occur just anywhere in the
  5422 text; the fixed correlation with particular command syntax has been
  5423 discontinued;
  5424 
  5425 * Pure: new method 'rules' is particularly well-suited for proof
  5426 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  5427 but often produces more compact proof terms with less detours;
  5428 
  5429 * Pure/Provers/classical: simplified integration with pure rule
  5430 attributes and methods; the classical "intro?/elim?/dest?"
  5431 declarations coincide with the pure ones; the "rule" method no longer
  5432 includes classically swapped intros; "intro" and "elim" methods no
  5433 longer pick rules from the context; also got rid of ML declarations
  5434 AddXIs/AddXEs/AddXDs; all of this has some potential for
  5435 INCOMPATIBILITY;
  5436 
  5437 * Provers/classical: attribute 'swapped' produces classical inversions
  5438 of introduction rules;
  5439 
  5440 * Provers/simplifier: 'simplified' attribute may refer to explicit
  5441 rules instead of full simplifier context; 'iff' attribute handles
  5442 conditional rules;
  5443 
  5444 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  5445 
  5446 * HOL: 'recdef' now fails on unfinished automated proofs, use
  5447 "(permissive)" option to recover old behavior;
  5448 
  5449 * HOL: 'inductive' no longer features separate (collective) attributes
  5450 for 'intros' (was found too confusing);
  5451 
  5452 * HOL: properly declared induction rules less_induct and
  5453 wf_induct_rule;
  5454 
  5455 
  5456 *** HOL ***
  5457 
  5458 * HOL: moved over to sane numeral syntax; the new policy is as
  5459 follows:
  5460 
  5461   - 0 and 1 are polymorphic constants, which are defined on any
  5462   numeric type (nat, int, real etc.);
  5463 
  5464   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  5465   binary representation internally;
  5466 
  5467   - type nat has special constructor Suc, and generally prefers Suc 0
  5468   over 1::nat and Suc (Suc 0) over 2::nat;
  5469 
  5470 This change may cause significant problems of INCOMPATIBILITY; here
  5471 are some hints on converting existing sources:
  5472 
  5473   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  5474   entities, so expressions involving "-" (unary or binary minus) need
  5475   to be spaced properly;
  5476 
  5477   - existing occurrences of "1" may need to be constraint "1::nat" or
  5478   even replaced by Suc 0; similar for old "2";
  5479 
  5480   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  5481 
  5482   - remove all special provisions on numerals in proofs;
  5483 
  5484 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  5485 representation (depends on bin_arith_simps in the default context);
  5486 
  5487 * HOL: symbolic syntax for x^2 (numeral 2);
  5488 
  5489 * HOL: the class of all HOL types is now called "type" rather than
  5490 "term"; INCOMPATIBILITY, need to adapt references to this type class
  5491 in axclass/classes, instance/arities, and (usually rare) occurrences
  5492 in typings (of consts etc.); internally the class is called
  5493 "HOL.type", ML programs should refer to HOLogic.typeS;
  5494 
  5495 * HOL/record package improvements:
  5496   - new derived operations "fields" to build a partial record section,
  5497     "extend" to promote a fixed record to a record scheme, and
  5498     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  5499     declared as simp by default;
  5500   - shared operations ("more", "fields", etc.) now need to be always
  5501     qualified) --- potential INCOMPATIBILITY;
  5502   - removed "make_scheme" operations (use "make" with "extend") --
  5503     INCOMPATIBILITY;
  5504   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  5505   - provides cases/induct rules for use with corresponding Isar
  5506     methods (for concrete records, record schemes, concrete more
  5507     parts, and schematic more parts -- in that order);
  5508   - internal definitions directly based on a light-weight abstract
  5509     theory of product types over typedef rather than datatype;
  5510 
  5511 * HOL: generic code generator for generating executable ML code from
  5512 specifications; specific support for HOL constructs such as inductive
  5513 datatypes and sets, as well as recursive functions; can be invoked
  5514 via 'generate_code' theory section;
  5515 
  5516 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  5517 
  5518 * HOL: consolidated and renamed several theories.  In particular:
  5519         Ord.thy has been absorbed into HOL.thy
  5520         String.thy has been absorbed into List.thy
  5521 
  5522 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  5523 (beware of argument permutation!);
  5524 
  5525 * HOL: linorder_less_split superseded by linorder_cases;
  5526 
  5527 * HOL/List: "nodups" renamed to "distinct";
  5528 
  5529 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  5530 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  5531   - Ex_def has changed, now need to use some_eq_ex
  5532 
  5533 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  5534 in this (rare) case use:
  5535 
  5536   delSWrapper "split_all_tac"
  5537   addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
  5538 
  5539 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
  5540 MAY FAIL;
  5541 
  5542 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
  5543 Isabelle's type classes, ^ on functions and relations has too general
  5544 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be
  5545 necessary to attach explicit type constraints;
  5546 
  5547 * HOL/Relation: the prefix name of the infix "O" has been changed from
  5548 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been
  5549 renamed accordingly (eg "compI" -> "rel_compI").
  5550 
  5551 * HOL: syntax translations now work properly with numerals and records
  5552 expressions;
  5553 
  5554 * HOL: bounded abstraction now uses syntax "%" / "\<lambda>" instead
  5555 of "lam" -- INCOMPATIBILITY;
  5556 
  5557 * HOL: got rid of some global declarations (potential INCOMPATIBILITY
  5558 for ML tools): const "()" renamed "Product_Type.Unity", type "unit"
  5559 renamed "Product_Type.unit";
  5560 
  5561 * HOL: renamed rtrancl_into_rtrancl2 to converse_rtrancl_into_rtrancl
  5562 
  5563 * HOL: removed obsolete theorem "optionE" (use "option.exhaust", or
  5564 the "cases" method);
  5565 
  5566 * HOL/GroupTheory: group theory examples including Sylow's theorem (by
  5567 Florian Kammller);
  5568 
  5569 * HOL/IMP: updated and converted to new-style theory format; several
  5570 parts turned into readable document, with proper Isar proof texts and
  5571 some explanations (by Gerwin Klein);
  5572 
  5573 * HOL-Real: added Complex_Numbers (by Gertrud Bauer);
  5574 
  5575 * HOL-Hyperreal is now a logic image;
  5576 
  5577 
  5578 *** HOLCF ***
  5579 
  5580 * Isar: consts/constdefs supports mixfix syntax for continuous
  5581 operations;
  5582 
  5583 * Isar: domain package adapted to new-style theory format, e.g. see
  5584 HOLCF/ex/Dnat.thy;
  5585 
  5586 * theory Lift: proper use of rep_datatype lift instead of ML hacks --
  5587 potential INCOMPATIBILITY; now use plain induct_tac instead of former
  5588 lift.induct_tac, always use UU instead of Undef;
  5589 
  5590 * HOLCF/IMP: updated and converted to new-style theory;
  5591 
  5592 
  5593 *** ZF ***
  5594 
  5595 * Isar: proper integration of logic-specific tools and packages,
  5596 including theory commands '(co)inductive', '(co)datatype',
  5597 'rep_datatype', 'inductive_cases', as well as methods 'ind_cases',
  5598 'induct_tac', 'case_tac', and 'typecheck' (with attribute 'TC');
  5599 
  5600 * theory Main no longer includes AC; for the Axiom of Choice, base
  5601 your theory on Main_ZFC;
  5602 
  5603 * the integer library now covers quotients and remainders, with many
  5604 laws relating division to addition, multiplication, etc.;
  5605 
  5606 * ZF/UNITY: Chandy and Misra's UNITY is now available in ZF, giving a
  5607 typeless version of the formalism;
  5608 
  5609 * ZF/AC, Coind, IMP, Resid: updated and converted to new-style theory
  5610 format;
  5611 
  5612 * ZF/Induct: new directory for examples of inductive definitions,
  5613 including theory Multiset for multiset orderings; converted to
  5614 new-style theory format;
  5615 
  5616 * ZF: many new theorems about lists, ordinals, etc.;
  5617 
  5618 
  5619 *** General ***
  5620 
  5621 * Pure/kernel: meta-level proof terms (by Stefan Berghofer); reference
  5622 variable proof controls level of detail: 0 = no proofs (only oracle
  5623 dependencies), 1 = lemma dependencies, 2 = compact proof terms; see
  5624 also ref manual for further ML interfaces;
  5625 
  5626 * Pure/axclass: removed obsolete ML interface
  5627 goal_subclass/goal_arity;
  5628 
  5629 * Pure/syntax: new token syntax "num" for plain numerals (without "#"
  5630 of "xnum"); potential INCOMPATIBILITY, since -0, -1 etc. are now
  5631 separate tokens, so expressions involving minus need to be spaced
  5632 properly;
  5633 
  5634 * Pure/syntax: support non-oriented infixes, using keyword "infix"
  5635 rather than "infixl" or "infixr";
  5636 
  5637 * Pure/syntax: concrete syntax for dummy type variables admits genuine
  5638 sort constraint specifications in type inference; e.g. "x::_::foo"
  5639 ensures that the type of "x" is of sort "foo" (but not necessarily a
  5640 type variable);
  5641 
  5642 * Pure/syntax: print modes "type_brackets" and "no_type_brackets"
  5643 control output of nested => (types); the default behavior is
  5644 "type_brackets";
  5645 
  5646 * Pure/syntax: builtin parse translation for "_constify" turns valued
  5647 tokens into AST constants;
  5648 
  5649 * Pure/syntax: prefer later declarations of translations and print
  5650 translation functions; potential INCOMPATIBILITY: need to reverse
  5651 multiple declarations for same syntax element constant;
  5652 
  5653 * Pure/show_hyps reset by default (in accordance to existing Isar
  5654 practice);
  5655 
  5656 * Provers/classical: renamed addaltern to addafter, addSaltern to
  5657 addSafter;
  5658 
  5659 * Provers/clasimp: ``iff'' declarations now handle conditional rules
  5660 as well;
  5661 
  5662 * system: tested support for MacOS X; should be able to get Isabelle +
  5663 Proof General to work in a plain Terminal after installing Poly/ML
  5664 (e.g. from the Isabelle distribution area) and GNU bash alone
  5665 (e.g. from http://www.apple.com); full X11, XEmacs and X-Symbol
  5666 support requires further installations, e.g. from
  5667 http://fink.sourceforge.net/);
  5668 
  5669 * system: support Poly/ML 4.1.1 (able to manage larger heaps);
  5670 
  5671 * system: reduced base memory usage by Poly/ML (approx. 20 MB instead
  5672 of 40 MB), cf. ML_OPTIONS;
  5673 
  5674 * system: Proof General keywords specification is now part of the
  5675 Isabelle distribution (see etc/isar-keywords.el);
  5676 
  5677 * system: support for persistent Proof General sessions (refrain from
  5678 outdating all loaded theories on startup); user may create writable
  5679 logic images like this: ``isabelle -q HOL Test'';
  5680 
  5681 * system: smart selection of Isabelle process versus Isabelle
  5682 interface, accommodates case-insensitive file systems (e.g. HFS+); may
  5683 run both "isabelle" and "Isabelle" even if file names are badly
  5684 damaged (executable inspects the case of the first letter of its own
  5685 name); added separate "isabelle-process" and "isabelle-interface";
  5686 
  5687 * system: refrain from any attempt at filtering input streams; no
  5688 longer support ``8bit'' encoding of old isabelle font, instead proper
  5689 iso-latin characters may now be used; the related isatools
  5690 "symbolinput" and "nonascii" have disappeared as well;
  5691 
  5692 * system: removed old "xterm" interface (the print modes "xterm" and
  5693 "xterm_color" are still available for direct use in a suitable
  5694 terminal);
  5695 
  5696 
  5697 
  5698 New in Isabelle99-2 (February 2001)
  5699 -----------------------------------
  5700 
  5701 *** Overview of INCOMPATIBILITIES ***
  5702 
  5703 * HOL: please note that theories in the Library and elsewhere often use the
  5704 new-style (Isar) format; to refer to their theorems in an ML script you must
  5705 bind them to ML identifers by e.g.      val thm_name = thm "thm_name";
  5706 
  5707 * HOL: inductive package no longer splits induction rule aggressively,
  5708 but only as far as specified by the introductions given; the old
  5709 format may be recovered via ML function complete_split_rule or attribute
  5710 'split_rule (complete)';
  5711 
  5712 * HOL: induct renamed to lfp_induct, lfp_Tarski to lfp_unfold,
  5713 gfp_Tarski to gfp_unfold;
  5714 
  5715 * HOL: contrapos, contrapos2 renamed to contrapos_nn, contrapos_pp;
  5716 
  5717 * HOL: infix "dvd" now has priority 50 rather than 70 (because it is a
  5718 relation); infix "^^" has been renamed "``"; infix "``" has been
  5719 renamed "`"; "univalent" has been renamed "single_valued";
  5720 
  5721 * HOL/Real: "rinv" and "hrinv" replaced by overloaded "inverse"
  5722 operation;
  5723 
  5724 * HOLCF: infix "`" has been renamed "$"; the symbol syntax is \<cdot>;
  5725 
  5726 * Isar: 'obtain' no longer declares "that" fact as simp/intro;
  5727 
  5728 * Isar/HOL: method 'induct' now handles non-atomic goals; as a
  5729 consequence, it is no longer monotonic wrt. the local goal context
  5730 (which is now passed through the inductive cases);
  5731 
  5732 * Document preparation: renamed standard symbols \<ll> to \<lless> and
  5733 \<gg> to \<ggreater>;
  5734 
  5735 
  5736 *** Document preparation ***
  5737 
  5738 * \isabellestyle{NAME} selects version of Isabelle output (currently
  5739 available: are "it" for near math-mode best-style output, "sl" for
  5740 slanted text style, and "tt" for plain type-writer; if no
  5741 \isabellestyle command is given, output is according to slanted
  5742 type-writer);
  5743 
  5744 * support sub/super scripts (for single symbols only), input syntax is
  5745 like this: "A\<^sup>*" or "A\<^sup>\<star>";
  5746 
  5747 * some more standard symbols; see Appendix A of the system manual for
  5748 the complete list of symbols defined in isabellesym.sty;
  5749 
  5750 * improved isabelle style files; more abstract symbol implementation
  5751 (should now use \isamath{...} and \isatext{...} in custom symbol
  5752 definitions);
  5753 
  5754 * antiquotation @{goals} and @{subgoals} for output of *dynamic* goals
  5755 state; Note that presentation of goal states does not conform to
  5756 actual human-readable proof documents.  Please do not include goal
  5757 states into document output unless you really know what you are doing!
  5758 
  5759 * proper indentation of antiquoted output with proportional LaTeX
  5760 fonts;
  5761 
  5762 * no_document ML operator temporarily disables LaTeX document
  5763 generation;
  5764 
  5765 * isatool unsymbolize tunes sources for plain ASCII communication;
  5766 
  5767 
  5768 *** Isar ***
  5769 
  5770 * Pure: Isar now suffers initial goal statements to contain unbound
  5771 schematic variables (this does not conform to actual readable proof
  5772 documents, due to unpredictable outcome and non-compositional proof
  5773 checking); users who know what they are doing may use schematic goals
  5774 for Prolog-style synthesis of proven results;
  5775 
  5776 * Pure: assumption method (an implicit finishing) now handles actual
  5777 rules as well;
  5778 
  5779 * Pure: improved 'obtain' --- moved to Pure, insert "that" into
  5780 initial goal, declare "that" only as Pure intro (only for single
  5781 steps); the "that" rule assumption may now be involved in implicit
  5782 finishing, thus ".." becomes a feasible for trivial obtains;
  5783 
  5784 * Pure: default proof step now includes 'intro_classes'; thus trivial
  5785 instance proofs may be performed by "..";
  5786 
  5787 * Pure: ?thesis / ?this / "..." now work for pure meta-level
  5788 statements as well;
  5789 
  5790 * Pure: more robust selection of calculational rules;
  5791 
  5792 * Pure: the builtin notion of 'finished' goal now includes the ==-refl
  5793 rule (as well as the assumption rule);
  5794 
  5795 * Pure: 'thm_deps' command visualizes dependencies of theorems and
  5796 lemmas, using the graph browser tool;
  5797 
  5798 * Pure: predict failure of "show" in interactive mode;
  5799 
  5800 * Pure: 'thms_containing' now takes actual terms as arguments;
  5801 
  5802 * HOL: improved method 'induct' --- now handles non-atomic goals
  5803 (potential INCOMPATIBILITY); tuned error handling;
  5804 
  5805 * HOL: cases and induct rules now provide explicit hints about the
  5806 number of facts to be consumed (0 for "type" and 1 for "set" rules);
  5807 any remaining facts are inserted into the goal verbatim;
  5808 
  5809 * HOL: local contexts (aka cases) may now contain term bindings as
  5810 well; the 'cases' and 'induct' methods new provide a ?case binding for
  5811 the result to be shown in each case;
  5812 
  5813 * HOL: added 'recdef_tc' command;
  5814 
  5815 * isatool convert assists in eliminating legacy ML scripts;
  5816 
  5817 
  5818 *** HOL ***
  5819 
  5820 * HOL/Library: a collection of generic theories to be used together
  5821 with main HOL; the theory loader path already includes this directory
  5822 by default; the following existing theories have been moved here:
  5823 HOL/Induct/Multiset, HOL/Induct/Acc (as Accessible_Part), HOL/While
  5824 (as While_Combinator), HOL/Lex/Prefix (as List_Prefix);
  5825 
  5826 * HOL/Unix: "Some aspects of Unix file-system security", a typical
  5827 modelling and verification task performed in Isabelle/HOL +
  5828 Isabelle/Isar + Isabelle document preparation (by Markus Wenzel).
  5829 
  5830 * HOL/Algebra: special summation operator SUM no longer exists, it has
  5831 been replaced by setsum; infix 'assoc' now has priority 50 (like
  5832 'dvd'); axiom 'one_not_zero' has been moved from axclass 'ring' to
  5833 'domain', this makes the theory consistent with mathematical
  5834 literature;
  5835 
  5836 * HOL basics: added overloaded operations "inverse" and "divide"
  5837 (infix "/"), syntax for generic "abs" operation, generic summation
  5838 operator \<Sum>;
  5839 
  5840 * HOL/typedef: simplified package, provide more useful rules (see also
  5841 HOL/subset.thy);
  5842 
  5843 * HOL/datatype: induction rule for arbitrarily branching datatypes is
  5844 now expressed as a proper nested rule (old-style tactic scripts may
  5845 require atomize_strip_tac to cope with non-atomic premises);
  5846 
  5847 * HOL: renamed theory "Prod" to "Product_Type", renamed "split" rule
  5848 to "split_conv" (old name still available for compatibility);
  5849 
  5850 * HOL: improved concrete syntax for strings (e.g. allows translation
  5851 rules with string literals);
  5852 
  5853 * HOL-Real-Hyperreal: this extends HOL-Real with the hyperreals
  5854  and Fleuriot's mechanization of analysis, including the transcendental
  5855  functions for the reals;
  5856 
  5857 * HOL/Real, HOL/Hyperreal: improved arithmetic simplification;
  5858 
  5859 
  5860 *** CTT ***
  5861 
  5862 * CTT: x-symbol support for Pi, Sigma, -->, : (membership); note that
  5863 "lam" is displayed as TWO lambda-symbols
  5864 
  5865 * CTT: theory Main now available, containing everything (that is, Bool
  5866 and Arith);
  5867 
  5868 
  5869 *** General ***
  5870 
  5871 * Pure: the Simplifier has been implemented properly as a derived rule
  5872 outside of the actual kernel (at last!); the overall performance
  5873 penalty in practical applications is about 50%, while reliability of
  5874 the Isabelle inference kernel has been greatly improved;
  5875 
  5876 * print modes "brackets" and "no_brackets" control output of nested =>
  5877 (types) and ==> (props); the default behaviour is "brackets";
  5878 
  5879 * Provers: fast_tac (and friends) now handle actual object-logic rules
  5880 as assumptions as well;
  5881 
  5882 * system: support Poly/ML 4.0;
  5883 
  5884 * system: isatool install handles KDE version 1 or 2;
  5885 
  5886 
  5887 
  5888 New in Isabelle99-1 (October 2000)
  5889 ----------------------------------
  5890 
  5891 *** Overview of INCOMPATIBILITIES ***
  5892 
  5893 * HOL: simplification of natural numbers is much changed; to partly
  5894 recover the old behaviour (e.g. to prevent n+n rewriting to #2*n)
  5895 issue the following ML commands:
  5896 
  5897   Delsimprocs Nat_Numeral_Simprocs.cancel_numerals;
  5898   Delsimprocs [Nat_Numeral_Simprocs.combine_numerals];
  5899 
  5900 * HOL: simplification no longer dives into case-expressions; this is
  5901 controlled by "t.weak_case_cong" for each datatype t;
  5902 
  5903 * HOL: nat_less_induct renamed to less_induct;
  5904 
  5905 * HOL: systematic renaming of the SOME (Eps) rules, may use isatool
  5906 fixsome to patch .thy and .ML sources automatically;
  5907 
  5908   select_equality  -> some_equality
  5909   select_eq_Ex     -> some_eq_ex
  5910   selectI2EX       -> someI2_ex
  5911   selectI2         -> someI2
  5912   selectI          -> someI
  5913   select1_equality -> some1_equality
  5914   Eps_sym_eq       -> some_sym_eq_trivial
  5915   Eps_eq           -> some_eq_trivial
  5916 
  5917 * HOL: exhaust_tac on datatypes superceded by new generic case_tac;
  5918 
  5919 * HOL: removed obsolete theorem binding expand_if (refer to split_if
  5920 instead);
  5921 
  5922 * HOL: the recursion equations generated by 'recdef' are now called
  5923 f.simps instead of f.rules;
  5924 
  5925 * HOL: qed_spec_mp now also handles bounded ALL as well;
  5926 
  5927 * HOL: 0 is now overloaded, so the type constraint ":: nat" may
  5928 sometimes be needed;
  5929 
  5930 * HOL: the constant for "f``x" is now "image" rather than "op ``";
  5931 
  5932 * HOL: the constant for "f-``x" is now "vimage" rather than "op -``";
  5933 
  5934 * HOL: the disjoint sum is now "<+>" instead of "Plus"; the cartesian
  5935 product is now "<*>" instead of "Times"; the lexicographic product is
  5936 now "<*lex*>" instead of "**";
  5937 
  5938 * HOL: theory Sexp is now in HOL/Induct examples (it used to be part
  5939 of main HOL, but was unused); better use HOL's datatype package;
  5940 
  5941 * HOL: removed "symbols" syntax for constant "override" of theory Map;
  5942 the old syntax may be recovered as follows:
  5943 
  5944   syntax (symbols)
  5945     override  :: "('a ~=> 'b) => ('a ~=> 'b) => ('a ~=> 'b)"
  5946       (infixl "\\<oplus>" 100)
  5947 
  5948 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  5949 
  5950 * HOL/ML: even fewer consts are declared as global (see theories Ord,
  5951 Lfp, Gfp, WF); this only affects ML packages that refer to const names
  5952 internally;
  5953 
  5954 * HOL and ZF: syntax for quotienting wrt an equivalence relation
  5955 changed from A/r to A//r;
  5956 
  5957 * ZF: new treatment of arithmetic (nat & int) may break some old
  5958 proofs;
  5959 
  5960 * Isar: renamed some attributes (RS -> THEN, simplify -> simplified,
  5961 rulify -> rule_format, elimify -> elim_format, ...);
  5962 
  5963 * Isar/Provers: intro/elim/dest attributes changed; renamed
  5964 intro/intro!/intro!! flags to intro!/intro/intro? (in most cases, one
  5965 should have to change intro!! to intro? only); replaced "delrule" by
  5966 "rule del";
  5967 
  5968 * Isar/HOL: renamed "intrs" to "intros" in inductive definitions;
  5969 
  5970 * Provers: strengthened force_tac by using new first_best_tac;
  5971 
  5972 * LaTeX document preparation: several changes of isabelle.sty (see
  5973 lib/texinputs);
  5974 
  5975 
  5976 *** Document preparation ***
  5977 
  5978 * formal comments (text blocks etc.) in new-style theories may now
  5979 contain antiquotations of thm/prop/term/typ/text to be presented
  5980 according to latex print mode; concrete syntax is like this:
  5981 @{term[show_types] "f(x) = a + x"};
  5982 
  5983 * isatool mkdir provides easy setup of Isabelle session directories,
  5984 including proper document sources;
  5985 
  5986 * generated LaTeX sources are now deleted after successful run
  5987 (isatool document -c); may retain a copy somewhere else via -D option
  5988 of isatool usedir;
  5989 
  5990 * isatool usedir -D now lets isatool latex -o sty update the Isabelle
  5991 style files, achieving self-contained LaTeX sources and simplifying
  5992 LaTeX debugging;
  5993 
  5994 * old-style theories now produce (crude) LaTeX output as well;
  5995 
  5996 * browser info session directories are now self-contained (may be put
  5997 on WWW server seperately); improved graphs of nested sessions; removed
  5998 graph for 'all sessions';
  5999 
  6000 * several improvements in isabelle style files; \isabellestyle{it}
  6001 produces fake math mode output; \isamarkupheader is now \section by
  6002 default; see lib/texinputs/isabelle.sty etc.;
  6003 
  6004 
  6005 *** Isar ***
  6006 
  6007 * Isar/Pure: local results and corresponding term bindings are now
  6008 subject to Hindley-Milner polymorphism (similar to ML); this
  6009 accommodates incremental type-inference very nicely;
  6010 
  6011 * Isar/Pure: new derived language element 'obtain' supports
  6012 generalized existence reasoning;
  6013 
  6014 * Isar/Pure: new calculational elements 'moreover' and 'ultimately'
  6015 support accumulation of results, without applying any rules yet;
  6016 useful to collect intermediate results without explicit name
  6017 references, and for use with transitivity rules with more than 2
  6018 premises;
  6019 
  6020 * Isar/Pure: scalable support for case-analysis type proofs: new
  6021 'case' language element refers to local contexts symbolically, as
  6022 produced by certain proof methods; internally, case names are attached
  6023 to theorems as "tags";
  6024 
  6025 * Isar/Pure: theory command 'hide' removes declarations from
  6026 class/type/const name spaces;
  6027 
  6028 * Isar/Pure: theory command 'defs' supports option "(overloaded)" to
  6029 indicate potential overloading;
  6030 
  6031 * Isar/Pure: changed syntax of local blocks from {{ }} to { };
  6032 
  6033 * Isar/Pure: syntax of sorts made 'inner', i.e. have to write
  6034 "{a,b,c}" instead of {a,b,c};
  6035 
  6036 * Isar/Pure now provides its own version of intro/elim/dest
  6037 attributes; useful for building new logics, but beware of confusion
  6038 with the version in Provers/classical;
  6039 
  6040 * Isar/Pure: the local context of (non-atomic) goals is provided via
  6041 case name 'antecedent';
  6042 
  6043 * Isar/Pure: removed obsolete 'transfer' attribute (transfer of thms
  6044 to the current context is now done automatically);
  6045 
  6046 * Isar/Pure: theory command 'method_setup' provides a simple interface
  6047 for definining proof methods in ML;
  6048 
  6049 * Isar/Provers: intro/elim/dest attributes changed; renamed
  6050 intro/intro!/intro!! flags to intro!/intro/intro? (INCOMPATIBILITY, in
  6051 most cases, one should have to change intro!! to intro? only);
  6052 replaced "delrule" by "rule del";
  6053 
  6054 * Isar/Provers: new 'hypsubst' method, plain 'subst' method and
  6055 'symmetric' attribute (the latter supercedes [RS sym]);
  6056 
  6057 * Isar/Provers: splitter support (via 'split' attribute and 'simp'
  6058 method modifier); 'simp' method: 'only:' modifier removes loopers as
  6059 well (including splits);
  6060 
  6061 * Isar/Provers: Simplifier and Classical methods now support all kind
  6062 of modifiers used in the past, including 'cong', 'iff', etc.
  6063 
  6064 * Isar/Provers: added 'fastsimp' and 'clarsimp' methods (combination
  6065 of Simplifier and Classical reasoner);
  6066 
  6067 * Isar/HOL: new proof method 'cases' and improved version of 'induct'
  6068 now support named cases; major packages (inductive, datatype, primrec,
  6069 recdef) support case names and properly name parameters;
  6070 
  6071 * Isar/HOL: new transitivity rules for substitution in inequalities --
  6072 monotonicity conditions are extracted to be proven at end of
  6073 calculations;
  6074 
  6075 * Isar/HOL: removed 'case_split' thm binding, should use 'cases' proof
  6076 method anyway;
  6077 
  6078 * Isar/HOL: removed old expand_if = split_if; theorems if_splits =
  6079 split_if split_if_asm; datatype package provides theorems foo.splits =
  6080 foo.split foo.split_asm for each datatype;
  6081 
  6082 * Isar/HOL: tuned inductive package, rename "intrs" to "intros"
  6083 (potential INCOMPATIBILITY), emulation of mk_cases feature for proof
  6084 scripts: new 'inductive_cases' command and 'ind_cases' method; (Note:
  6085 use "(cases (simplified))" method in proper proof texts);
  6086 
  6087 * Isar/HOL: added global 'arith_split' attribute for 'arith' method;
  6088 
  6089 * Isar: names of theorems etc. may be natural numbers as well;
  6090 
  6091 * Isar: 'pr' command: optional arguments for goals_limit and
  6092 ProofContext.prems_limit; no longer prints theory contexts, but only
  6093 proof states;
  6094 
  6095 * Isar: diagnostic commands 'pr', 'thm', 'prop', 'term', 'typ' admit
  6096 additional print modes to be specified; e.g. "pr(latex)" will print
  6097 proof state according to the Isabelle LaTeX style;
  6098 
  6099 * Isar: improved support for emulating tactic scripts, including proof
  6100 methods 'rule_tac' etc., 'cut_tac', 'thin_tac', 'subgoal_tac',
  6101 'rename_tac', 'rotate_tac', 'tactic', and 'case_tac' / 'induct_tac'
  6102 (for HOL datatypes);
  6103 
  6104 * Isar: simplified (more robust) goal selection of proof methods: 1st
  6105 goal, all goals, or explicit goal specifier (tactic emulation); thus
  6106 'proof method scripts' have to be in depth-first order;
  6107 
  6108 * Isar: tuned 'let' syntax: replaced 'as' keyword by 'and';
  6109 
  6110 * Isar: removed 'help' command, which hasn't been too helpful anyway;
  6111 should instead use individual commands for printing items
  6112 (print_commands, print_methods etc.);
  6113 
  6114 * Isar: added 'nothing' --- the empty list of theorems;
  6115 
  6116 
  6117 *** HOL ***
  6118 
  6119 * HOL/MicroJava: formalization of a fragment of Java, together with a
  6120 corresponding virtual machine and a specification of its bytecode
  6121 verifier and a lightweight bytecode verifier, including proofs of
  6122 type-safety; by Gerwin Klein, Tobias Nipkow, David von Oheimb, and
  6123 Cornelia Pusch (see also the homepage of project Bali at
  6124 http://isabelle.in.tum.de/Bali/);
  6125 
  6126 * HOL/Algebra: new theory of rings and univariate polynomials, by
  6127 Clemens Ballarin;
  6128 
  6129 * HOL/NumberTheory: fundamental Theorem of Arithmetic, Chinese
  6130 Remainder Theorem, Fermat/Euler Theorem, Wilson's Theorem, by Thomas M
  6131 Rasmussen;
  6132 
  6133 * HOL/Lattice: fundamental concepts of lattice theory and order
  6134 structures, including duals, properties of bounds versus algebraic
  6135 laws, lattice operations versus set-theoretic ones, the Knaster-Tarski
  6136 Theorem for complete lattices etc.; may also serve as a demonstration
  6137 for abstract algebraic reasoning using axiomatic type classes, and
  6138 mathematics-style proof in Isabelle/Isar; by Markus Wenzel;
  6139 
  6140 * HOL/Prolog: a (bare-bones) implementation of Lambda-Prolog, by David
  6141 von Oheimb;
  6142 
  6143 * HOL/IMPP: extension of IMP with local variables and mutually
  6144 recursive procedures, by David von Oheimb;
  6145 
  6146 * HOL/Lambda: converted into new-style theory and document;
  6147 
  6148 * HOL/ex/Multiquote: example of multiple nested quotations and
  6149 anti-quotations -- basically a generalized version of de-Bruijn
  6150 representation; very useful in avoiding lifting of operations;
  6151 
  6152 * HOL/record: added general record equality rule to simpset; fixed
  6153 select-update simplification procedure to handle extended records as
  6154 well; admit "r" as field name;
  6155 
  6156 * HOL: 0 is now overloaded over the new sort "zero", allowing its use with
  6157 other numeric types and also as the identity of groups, rings, etc.;
  6158 
  6159 * HOL: new axclass plus_ac0 for addition with the AC-laws and 0 as identity.
  6160 Types nat and int belong to this axclass;
  6161 
  6162 * HOL: greatly improved simplification involving numerals of type nat, int, real:
  6163    (i + #8 + j) = Suc k simplifies to  #7 + (i + j) = k
  6164    i*j + k + j*#3*i     simplifies to  #4*(i*j) + k
  6165   two terms #m*u and #n*u are replaced by #(m+n)*u
  6166     (where #m, #n and u can implicitly be 1; this is simproc combine_numerals)
  6167   and the term/formula #m*u+x ~~ #n*u+y simplifies simplifies to #(m-n)+x ~~ y
  6168     or x ~~ #(n-m)+y, where ~~ is one of = < <= or - (simproc cancel_numerals);
  6169 
  6170 * HOL: meson_tac is available (previously in ex/meson.ML); it is a
  6171 powerful prover for predicate logic but knows nothing of clasets; see
  6172 ex/mesontest.ML and ex/mesontest2.ML for example applications;
  6173 
  6174 * HOL: new version of "case_tac" subsumes both boolean case split and
  6175 "exhaust_tac" on datatypes; INCOMPATIBILITY: exhaust_tac no longer
  6176 exists, may define val exhaust_tac = case_tac for ad-hoc portability;
  6177 
  6178 * HOL: simplification no longer dives into case-expressions: only the
  6179 selector expression is simplified, but not the remaining arms; to
  6180 enable full simplification of case-expressions for datatype t, you may
  6181 remove t.weak_case_cong from the simpset, either globally (Delcongs
  6182 [thm"t.weak_case_cong"];) or locally (delcongs [...]).
  6183 
  6184 * HOL/recdef: the recursion equations generated by 'recdef' for
  6185 function 'f' are now called f.simps instead of f.rules; if all
  6186 termination conditions are proved automatically, these simplification
  6187 rules are added to the simpset, as in primrec; rules may be named
  6188 individually as well, resulting in a separate list of theorems for
  6189 each equation;
  6190 
  6191 * HOL/While is a new theory that provides a while-combinator. It
  6192 permits the definition of tail-recursive functions without the
  6193 provision of a termination measure. The latter is necessary once the
  6194 invariant proof rule for while is applied.
  6195 
  6196 * HOL: new (overloaded) notation for the set of elements below/above
  6197 some element: {..u}, {..u(}, {l..}, {)l..}. See theory SetInterval.
  6198 
  6199 * HOL: theorems impI, allI, ballI bound as "strip";
  6200 
  6201 * HOL: new tactic induct_thm_tac: thm -> string -> int -> tactic
  6202 induct_tac th "x1 ... xn" expects th to have a conclusion of the form
  6203 P v1 ... vn and abbreviates res_inst_tac [("v1","x1"),...,("vn","xn")] th;
  6204 
  6205 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  6206 
  6207 * HOL: theory Sexp now in HOL/Induct examples (it used to be part of
  6208 main HOL, but was unused);
  6209 
  6210 * HOL: fewer consts declared as global (e.g. have to refer to
  6211 "Lfp.lfp" instead of "lfp" internally; affects ML packages only);
  6212 
  6213 * HOL: tuned AST representation of nested pairs, avoiding bogus output
  6214 in case of overlap with user translations (e.g. judgements over
  6215 tuples); (note that the underlying logical represenation is still
  6216 bogus);
  6217 
  6218 
  6219 *** ZF ***
  6220 
  6221 * ZF: simplification automatically cancels common terms in arithmetic
  6222 expressions over nat and int;
  6223 
  6224 * ZF: new treatment of nat to minimize type-checking: all operators
  6225 coerce their operands to a natural number using the function natify,
  6226 making the algebraic laws unconditional;
  6227 
  6228 * ZF: as above, for int: operators coerce their operands to an integer
  6229 using the function intify;
  6230 
  6231 * ZF: the integer library now contains many of the usual laws for the
  6232 orderings, including $<=, and monotonicity laws for $+ and $*;