NEWS
author wenzelm
Fri Aug 27 12:40:20 2010 +0200 (2010-08-27)
changeset 38767 d8da44a8dd25
parent 38708 8915e3ce8655
child 38797 abe92b33ac9f
permissions -rw-r--r--
proper context for various Thy_Output options, via official configuration options in ML and Isar;
     1 Isabelle NEWS -- history user-relevant changes
     2 ==============================================
     3 
     4 New in this Isabelle version
     5 ----------------------------
     6 
     7 *** General ***
     8 
     9 * Explicit treatment of UTF8 sequences as Isabelle symbols, such that
    10 a Unicode character is treated as a single symbol, not a sequence of
    11 non-ASCII bytes as before.  Since Isabelle/ML string literals may
    12 contain symbols without further backslash escapes, Unicode can now be
    13 used here as well.  Recall that Symbol.explode in ML provides a
    14 consistent view on symbols, while raw explode (or String.explode)
    15 merely give a byte-oriented representation.
    16 
    17 * Theory loading: only the master source file is looked-up in the
    18 implicit load path, all other files are addressed relatively to its
    19 directory.  Minor INCOMPATIBILITY, subtle change in semantics.
    20 
    21 * Special treatment of ML file names has been discontinued.
    22 Historically, optional extensions .ML or .sml were added on demand --
    23 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
    24 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
    25 
    26 * Various options that affect document antiquotations are now properly
    27 handled within the context via configuration options, instead of
    28 unsynchronized references.  There are both ML Config.T entities and
    29 Isar declaration attributes to access these.
    30 
    31   ML:                       Isar:
    32 
    33   Thy_Output.display        thy_output_display
    34   Thy_Output.quotes         thy_output_quotes
    35   Thy_Output.indent         thy_output_indent
    36   Thy_Output.source         thy_output_source
    37   Thy_Output.break          thy_output_break
    38 
    39 Note that the corresponding "..._default" references may be only
    40 changed globally at the ROOT session setup, but *not* within a theory.
    41 
    42 
    43 *** Pure ***
    44 
    45 * Interpretation command 'interpret' accepts a list of equations like
    46 'interpretation' does.
    47 
    48 * Diagnostic command 'print_interps' prints interpretations in proofs
    49 in addition to interpretations in theories.
    50 
    51 * Discontinued obsolete 'global' and 'local' commands to manipulate
    52 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
    53 Sign.root_path and Sign.local_path may be applied directly where this
    54 feature is still required for historical reasons.
    55 
    56 
    57 *** HOL ***
    58 
    59 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
    60 
    61 * Theory SetsAndFunctions has been split into Function_Algebras and Set_Algebras;
    62 canonical names for instance definitions for functions; various improvements.
    63 INCOMPATIBILITY.
    64 
    65 * Records: logical foundation type for records do not carry a '_type' suffix
    66 any longer.  INCOMPATIBILITY.
    67 
    68 * Code generation for records: more idiomatic representation of record types.
    69 Warning: records are not covered by ancient SML code generation any longer.
    70 INCOMPATIBILITY.  In cases of need, a suitable rep_datatype declaration
    71 helps to succeed then:
    72 
    73   record 'a foo = ...
    74   ...
    75   rep_datatype foo_ext ...
    76 
    77 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
    78 INCOMPATIBILITY.
    79 
    80 * Quickcheck in locales considers interpretations of that locale for
    81 counter example search.
    82 
    83 * Theory Library/Monad_Syntax provides do-syntax for monad types.  Syntax
    84 in Library/State_Monad has been changed to avoid ambiguities.
    85 INCOMPATIBILITY.
    86 
    87 * Code generator: export_code without explicit file declaration prints
    88 to standard output.  INCOMPATIBILITY.
    89 
    90 * Abolished symbol type names:  "prod" and "sum" replace "*" and "+"
    91 respectively.  INCOMPATIBILITY.
    92 
    93 * Constant "split" has been merged with constant "prod_case";  names
    94 of ML functions, facts etc. involving split have been retained so far,
    95 though.  INCOMPATIBILITY.
    96 
    97 * Dropped old infix syntax "mem" for List.member;  use "in set"
    98 instead.  INCOMPATIBILITY.
    99 
   100 * Refactoring of code-generation specific operations in List.thy
   101 
   102   constants
   103     null ~> List.null
   104 
   105   facts
   106     mem_iff ~> member_def
   107     null_empty ~> null_def
   108 
   109 INCOMPATIBILITY.  Note that these were not suppossed to be used
   110 regularly unless for striking reasons;  their main purpose was code
   111 generation.
   112 
   113 * Some previously unqualified names have been qualified:
   114 
   115   types
   116     bool ~> HOL.bool
   117     nat ~> Nat.nat
   118 
   119   constants
   120     Trueprop ~> HOL.Trueprop
   121     True ~> HOL.True
   122     False ~> HOL.False
   123     Not ~> HOL.Not
   124     The ~> HOL.The
   125     All ~> HOL.All
   126     Ex ~> HOL.Ex
   127     Ex1 ~> HOL.Ex1
   128     Let ~> HOL.Let
   129     If ~> HOL.If
   130     Ball ~> Set.Ball
   131     Bex ~> Set.Bex
   132     Suc ~> Nat.Suc
   133     Pair ~> Product_Type.Pair
   134     fst ~> Product_Type.fst
   135     snd ~> Product_Type.snd
   136     curry ~> Product_Type.curry
   137     op : ~> Set.member
   138     Collect ~> Set.Collect
   139 
   140 INCOMPATIBILITY.
   141 
   142 * Removed simplifier congruence rule of "prod_case", as has for long
   143 been the case with "split".  INCOMPATIBILITY.
   144 
   145 * Datatype package: theorems generated for executable equality
   146 (class eq) carry proper names and are treated as default code
   147 equations.
   148 
   149 * List.thy: use various operations from the Haskell prelude when
   150 generating Haskell code.
   151 
   152 * code_simp.ML and method code_simp: simplification with rules determined
   153 by code generator.
   154 
   155 * code generator: do not print function definitions for case
   156 combinators any longer.
   157 
   158 * Multivariate Analysis: Introduced a type class for euclidean space. Most
   159 theorems are now stated in terms of euclidean spaces instead of finite
   160 cartesian products.
   161 
   162   types
   163     real ^ 'n ~>  'a::real_vector
   164               ~>  'a::euclidean_space
   165               ~>  'a::ordered_euclidean_space
   166         (depends on your needs)
   167 
   168   constants
   169      _ $ _        ~> _ $$ _
   170      \<chi> x. _  ~> \<chi>\<chi> x. _
   171      CARD('n)     ~> DIM('a)
   172 
   173 Also note that the indices are now natural numbers and not from some finite
   174 type. Finite cartesian products of euclidean spaces, products of euclidean
   175 spaces the real and complex numbers are instantiated to be euclidean_spaces.
   176 
   177 INCOMPATIBILITY.
   178 
   179 * Probability: Introduced pinfreal as real numbers with infinity. Use pinfreal
   180 as value for measures. Introduces Lebesgue Measure based on the integral in
   181 Multivariate Analysis. Proved Radon Nikodym for arbitrary sigma finite measure
   182 spaces.
   183 
   184  INCOMPATIBILITY.
   185 
   186 * Inductive package: offers new command "inductive_simps" to automatically
   187 derive instantiated and simplified equations for inductive predicates,
   188 similar to inductive_cases.
   189 
   190 
   191 *** FOL ***
   192 
   193 * All constant names are now qualified.  INCOMPATIBILITY.
   194 
   195 
   196 *** ZF ***
   197 
   198 * All constant names are now qualified.  INCOMPATIBILITY.
   199 
   200 
   201 *** ML ***
   202 
   203 * ML antiquotations @{theory} and @{theory_ref} refer to named
   204 theories from the ancestry of the current context, not any accidental
   205 theory loader state as before.  Potential INCOMPATIBILITY, subtle
   206 change in semantics.
   207 
   208 
   209 *** System ***
   210 
   211 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   212 
   213 
   214 
   215 New in Isabelle2009-2 (June 2010)
   216 ---------------------------------
   217 
   218 *** General ***
   219 
   220 * Authentic syntax for *all* logical entities (type classes, type
   221 constructors, term constants): provides simple and robust
   222 correspondence between formal entities and concrete syntax.  Within
   223 the parse tree / AST representations, "constants" are decorated by
   224 their category (class, type, const) and spelled out explicitly with
   225 their full internal name.
   226 
   227 Substantial INCOMPATIBILITY concerning low-level syntax declarations
   228 and translations (translation rules and translation functions in ML).
   229 Some hints on upgrading:
   230 
   231   - Many existing uses of 'syntax' and 'translations' can be replaced
   232     by more modern 'type_notation', 'notation' and 'abbreviation',
   233     which are independent of this issue.
   234 
   235   - 'translations' require markup within the AST; the term syntax
   236     provides the following special forms:
   237 
   238       CONST c   -- produces syntax version of constant c from context
   239       XCONST c  -- literally c, checked as constant from context
   240       c         -- literally c, if declared by 'syntax'
   241 
   242     Plain identifiers are treated as AST variables -- occasionally the
   243     system indicates accidental variables via the error "rhs contains
   244     extra variables".
   245 
   246     Type classes and type constructors are marked according to their
   247     concrete syntax.  Some old translations rules need to be written
   248     for the "type" category, using type constructor application
   249     instead of pseudo-term application of the default category
   250     "logic".
   251 
   252   - 'parse_translation' etc. in ML may use the following
   253     antiquotations:
   254 
   255       @{class_syntax c}   -- type class c within parse tree / AST
   256       @{term_syntax c}    -- type constructor c within parse tree / AST
   257       @{const_syntax c}   -- ML version of "CONST c" above
   258       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
   259 
   260   - Literal types within 'typed_print_translations', i.e. those *not*
   261     represented as pseudo-terms are represented verbatim.  Use @{class
   262     c} or @{type_name c} here instead of the above syntax
   263     antiquotations.
   264 
   265 Note that old non-authentic syntax was based on unqualified base
   266 names, so all of the above "constant" names would coincide.  Recall
   267 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
   268 diagnose syntax problems.
   269 
   270 * Type constructors admit general mixfix syntax, not just infix.
   271 
   272 * Concrete syntax may be attached to local entities without a proof
   273 body, too.  This works via regular mixfix annotations for 'fix',
   274 'def', 'obtain' etc. or via the explicit 'write' command, which is
   275 similar to the 'notation' command in theory specifications.
   276 
   277 * Discontinued unnamed infix syntax (legacy feature for many years) --
   278 need to specify constant name and syntax separately.  Internal ML
   279 datatype constructors have been renamed from InfixName to Infix etc.
   280 Minor INCOMPATIBILITY.
   281 
   282 * Schematic theorem statements need to be explicitly markup as such,
   283 via commands 'schematic_lemma', 'schematic_theorem',
   284 'schematic_corollary'.  Thus the relevance of the proof is made
   285 syntactically clear, which impacts performance in a parallel or
   286 asynchronous interactive environment.  Minor INCOMPATIBILITY.
   287 
   288 * Use of cumulative prems via "!" in some proof methods has been
   289 discontinued (old legacy feature).
   290 
   291 * References 'trace_simp' and 'debug_simp' have been replaced by
   292 configuration options stored in the context. Enabling tracing (the
   293 case of debugging is similar) in proofs works via
   294 
   295   using [[trace_simp = true]]
   296 
   297 Tracing is then active for all invocations of the simplifier in
   298 subsequent goal refinement steps. Tracing may also still be enabled or
   299 disabled via the ProofGeneral settings menu.
   300 
   301 * Separate commands 'hide_class', 'hide_type', 'hide_const',
   302 'hide_fact' replace the former 'hide' KIND command.  Minor
   303 INCOMPATIBILITY.
   304 
   305 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
   306 more efficient than combinations with -q1 or -q2.
   307 
   308 
   309 *** Pure ***
   310 
   311 * Proofterms record type-class reasoning explicitly, using the
   312 "unconstrain" operation internally.  This eliminates all sort
   313 constraints from a theorem and proof, introducing explicit
   314 OFCLASS-premises.  On the proof term level, this operation is
   315 automatically applied at theorem boundaries, such that closed proofs
   316 are always free of sort constraints.  INCOMPATIBILITY for tools that
   317 inspect proof terms.
   318 
   319 * Local theory specifications may depend on extra type variables that
   320 are not present in the result type -- arguments TYPE('a) :: 'a itself
   321 are added internally.  For example:
   322 
   323   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
   324 
   325 * Predicates of locales introduced by classes carry a mandatory
   326 "class" prefix.  INCOMPATIBILITY.
   327 
   328 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
   329 
   330 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
   331 'class' instead.
   332 
   333 * Command 'code_reflect' allows to incorporate generated ML code into
   334 runtime environment; replaces immature code_datatype antiquotation.
   335 INCOMPATIBILITY.
   336 
   337 * Code generator: simple concept for abstract datatypes obeying
   338 invariants.
   339 
   340 * Code generator: details of internal data cache have no impact on the
   341 user space functionality any longer.
   342 
   343 * Methods "unfold_locales" and "intro_locales" ignore non-locale
   344 subgoals.  This is more appropriate for interpretations with 'where'.
   345 INCOMPATIBILITY.
   346 
   347 * Command 'example_proof' opens an empty proof body.  This allows to
   348 experiment with Isar, without producing any persistent result.
   349 
   350 * Commands 'type_notation' and 'no_type_notation' declare type syntax
   351 within a local theory context, with explicit checking of the
   352 constructors involved (in contrast to the raw 'syntax' versions).
   353 
   354 * Commands 'types' and 'typedecl' now work within a local theory
   355 context -- without introducing dependencies on parameters or
   356 assumptions, which is not possible in Isabelle/Pure.
   357 
   358 * Command 'defaultsort' has been renamed to 'default_sort', it works
   359 within a local theory context.  Minor INCOMPATIBILITY.
   360 
   361 
   362 *** HOL ***
   363 
   364 * Command 'typedef' now works within a local theory context -- without
   365 introducing dependencies on parameters or assumptions, which is not
   366 possible in Isabelle/Pure/HOL.  Note that the logical environment may
   367 contain multiple interpretations of local typedefs (with different
   368 non-emptiness proofs), even in a global theory context.
   369 
   370 * New package for quotient types.  Commands 'quotient_type' and
   371 'quotient_definition' may be used for defining types and constants by
   372 quotient constructions.  An example is the type of integers created by
   373 quotienting pairs of natural numbers:
   374 
   375   fun
   376     intrel :: "(nat * nat) => (nat * nat) => bool"
   377   where
   378     "intrel (x, y) (u, v) = (x + v = u + y)"
   379 
   380   quotient_type int = "nat * nat" / intrel
   381     by (auto simp add: equivp_def expand_fun_eq)
   382 
   383   quotient_definition
   384     "0::int" is "(0::nat, 0::nat)"
   385 
   386 The method "lifting" can be used to lift of theorems from the
   387 underlying "raw" type to the quotient type.  The example
   388 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
   389 construction and provides a reasoning infrastructure for finite sets.
   390 
   391 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
   392 clash with new theory Quotient in Main HOL.
   393 
   394 * Moved the SMT binding into the main HOL session, eliminating
   395 separate HOL-SMT session.
   396 
   397 * List membership infix mem operation is only an input abbreviation.
   398 INCOMPATIBILITY.
   399 
   400 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
   401 for future developements; former Library/Word.thy is still present in
   402 the AFP entry RSAPPS.
   403 
   404 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
   405 longer shadowed.  INCOMPATIBILITY.
   406 
   407 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
   408 INCOMPATIBILITY.
   409 
   410 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
   411 INCOMPATIBILITY.
   412 
   413 * Dropped normalizing_semiring etc; use the facts in semiring classes
   414 instead.  INCOMPATIBILITY.
   415 
   416 * Dropped several real-specific versions of lemmas about floor and
   417 ceiling; use the generic lemmas from theory "Archimedean_Field"
   418 instead.  INCOMPATIBILITY.
   419 
   420   floor_number_of_eq         ~> floor_number_of
   421   le_floor_eq_number_of      ~> number_of_le_floor
   422   le_floor_eq_zero           ~> zero_le_floor
   423   le_floor_eq_one            ~> one_le_floor
   424   floor_less_eq_number_of    ~> floor_less_number_of
   425   floor_less_eq_zero         ~> floor_less_zero
   426   floor_less_eq_one          ~> floor_less_one
   427   less_floor_eq_number_of    ~> number_of_less_floor
   428   less_floor_eq_zero         ~> zero_less_floor
   429   less_floor_eq_one          ~> one_less_floor
   430   floor_le_eq_number_of      ~> floor_le_number_of
   431   floor_le_eq_zero           ~> floor_le_zero
   432   floor_le_eq_one            ~> floor_le_one
   433   floor_subtract_number_of   ~> floor_diff_number_of
   434   floor_subtract_one         ~> floor_diff_one
   435   ceiling_number_of_eq       ~> ceiling_number_of
   436   ceiling_le_eq_number_of    ~> ceiling_le_number_of
   437   ceiling_le_zero_eq         ~> ceiling_le_zero
   438   ceiling_le_eq_one          ~> ceiling_le_one
   439   less_ceiling_eq_number_of  ~> number_of_less_ceiling
   440   less_ceiling_eq_zero       ~> zero_less_ceiling
   441   less_ceiling_eq_one        ~> one_less_ceiling
   442   ceiling_less_eq_number_of  ~> ceiling_less_number_of
   443   ceiling_less_eq_zero       ~> ceiling_less_zero
   444   ceiling_less_eq_one        ~> ceiling_less_one
   445   le_ceiling_eq_number_of    ~> number_of_le_ceiling
   446   le_ceiling_eq_zero         ~> zero_le_ceiling
   447   le_ceiling_eq_one          ~> one_le_ceiling
   448   ceiling_subtract_number_of ~> ceiling_diff_number_of
   449   ceiling_subtract_one       ~> ceiling_diff_one
   450 
   451 * Theory "Finite_Set": various folding_XXX locales facilitate the
   452 application of the various fold combinators on finite sets.
   453 
   454 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
   455 provides abstract red-black tree type which is backed by "RBT_Impl" as
   456 implementation.  INCOMPATIBILTY.
   457 
   458 * Theory Library/Coinductive_List has been removed -- superseded by
   459 AFP/thys/Coinductive.
   460 
   461 * Theory PReal, including the type "preal" and related operations, has
   462 been removed.  INCOMPATIBILITY.
   463 
   464 * Real: new development using Cauchy Sequences.
   465 
   466 * Split off theory "Big_Operators" containing setsum, setprod,
   467 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
   468 
   469 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
   470 "Int" etc.  INCOMPATIBILITY.
   471 
   472 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
   473 
   474 * New set of rules "ac_simps" provides combined assoc / commute
   475 rewrites for all interpretations of the appropriate generic locales.
   476 
   477 * Renamed theory "OrderedGroup" to "Groups" and split theory
   478 "Ring_and_Field" into theories "Rings" and "Fields"; for more
   479 appropriate and more consistent names suitable for name prefixes
   480 within the HOL theories.  INCOMPATIBILITY.
   481 
   482 * Some generic constants have been put to appropriate theories:
   483   - less_eq, less: Orderings
   484   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
   485   - inverse, divide: Rings
   486 INCOMPATIBILITY.
   487 
   488 * More consistent naming of type classes involving orderings (and
   489 lattices):
   490 
   491     lower_semilattice                   ~> semilattice_inf
   492     upper_semilattice                   ~> semilattice_sup
   493 
   494     dense_linear_order                  ~> dense_linorder
   495 
   496     pordered_ab_group_add               ~> ordered_ab_group_add
   497     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
   498     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
   499     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
   500     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
   501     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
   502     pordered_cancel_semiring            ~> ordered_cancel_semiring
   503     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
   504     pordered_comm_ring                  ~> ordered_comm_ring
   505     pordered_comm_semiring              ~> ordered_comm_semiring
   506     pordered_ring                       ~> ordered_ring
   507     pordered_ring_abs                   ~> ordered_ring_abs
   508     pordered_semiring                   ~> ordered_semiring
   509 
   510     ordered_ab_group_add                ~> linordered_ab_group_add
   511     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
   512     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
   513     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
   514     ordered_field                       ~> linordered_field
   515     ordered_field_no_lb                 ~> linordered_field_no_lb
   516     ordered_field_no_ub                 ~> linordered_field_no_ub
   517     ordered_field_dense_linear_order    ~> dense_linordered_field
   518     ordered_idom                        ~> linordered_idom
   519     ordered_ring                        ~> linordered_ring
   520     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
   521     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
   522     ordered_ring_strict                 ~> linordered_ring_strict
   523     ordered_semidom                     ~> linordered_semidom
   524     ordered_semiring                    ~> linordered_semiring
   525     ordered_semiring_1                  ~> linordered_semiring_1
   526     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
   527     ordered_semiring_strict             ~> linordered_semiring_strict
   528 
   529   The following slightly odd type classes have been moved to a
   530   separate theory Library/Lattice_Algebras:
   531 
   532     lordered_ab_group_add               ~> lattice_ab_group_add
   533     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
   534     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
   535     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
   536     lordered_ring                       ~> lattice_ring
   537 
   538 INCOMPATIBILITY.
   539 
   540 * Refined field classes:
   541   - classes division_ring_inverse_zero, field_inverse_zero,
   542     linordered_field_inverse_zero include rule inverse 0 = 0 --
   543     subsumes former division_by_zero class;
   544   - numerous lemmas have been ported from field to division_ring.
   545 INCOMPATIBILITY.
   546 
   547 * Refined algebra theorem collections:
   548   - dropped theorem group group_simps, use algebra_simps instead;
   549   - dropped theorem group ring_simps, use field_simps instead;
   550   - proper theorem collection field_simps subsumes former theorem
   551     groups field_eq_simps and field_simps;
   552   - dropped lemma eq_minus_self_iff which is a duplicate for
   553     equal_neg_zero.
   554 INCOMPATIBILITY.
   555 
   556 * Theory Finite_Set and List: some lemmas have been generalized from
   557 sets to lattices:
   558 
   559   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
   560   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
   561   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
   562   union_Union_fold_union        ~> sup_Sup_fold_sup
   563   Inter_fold_inter              ~> Inf_fold_inf
   564   Union_fold_union              ~> Sup_fold_sup
   565   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
   566   union_UNION_fold_union        ~> sup_SUPR_fold_sup
   567   INTER_fold_inter              ~> INFI_fold_inf
   568   UNION_fold_union              ~> SUPR_fold_sup
   569 
   570 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
   571 replaced by the more convenient lemmas Inf_empty and Sup_empty.
   572 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
   573 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
   574 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
   575 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
   576 
   577 * Reorganized theory Multiset: swapped notation of pointwise and
   578 multiset order:
   579 
   580   - pointwise ordering is instance of class order with standard syntax
   581     <= and <;
   582   - multiset ordering has syntax <=# and <#; partial order properties
   583     are provided by means of interpretation with prefix
   584     multiset_order;
   585   - less duplication, less historical organization of sections,
   586     conversion from associations lists to multisets, rudimentary code
   587     generation;
   588   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
   589     if needed.
   590 
   591 Renamed:
   592 
   593   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
   594   multi_count_ext  ~>  multiset_ext
   595   diff_union_inverse2  ~>  diff_union_cancelR
   596 
   597 INCOMPATIBILITY.
   598 
   599 * Theory Permutation: replaced local "remove" by List.remove1.
   600 
   601 * Code generation: ML and OCaml code is decorated with signatures.
   602 
   603 * Theory List: added transpose.
   604 
   605 * Library/Nat_Bijection.thy is a collection of bijective functions
   606 between nat and other types, which supersedes the older libraries
   607 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
   608 
   609   Constants:
   610   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
   611   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
   612   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
   613   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
   614   Countable.pair_encode           ~> prod_encode
   615   NatIso.prod2nat                 ~> prod_encode
   616   NatIso.nat2prod                 ~> prod_decode
   617   NatIso.sum2nat                  ~> sum_encode
   618   NatIso.nat2sum                  ~> sum_decode
   619   NatIso.list2nat                 ~> list_encode
   620   NatIso.nat2list                 ~> list_decode
   621   NatIso.set2nat                  ~> set_encode
   622   NatIso.nat2set                  ~> set_decode
   623 
   624   Lemmas:
   625   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
   626   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
   627   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
   628   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
   629   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
   630   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
   631   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
   632   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
   633   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
   634   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
   635   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
   636   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
   637   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
   638 
   639 * Sledgehammer:
   640   - Renamed ATP commands:
   641     atp_info     ~> sledgehammer running_atps
   642     atp_kill     ~> sledgehammer kill_atps
   643     atp_messages ~> sledgehammer messages
   644     atp_minimize ~> sledgehammer minimize
   645     print_atps   ~> sledgehammer available_atps
   646     INCOMPATIBILITY.
   647   - Added user's manual ("isabelle doc sledgehammer").
   648   - Added option syntax and "sledgehammer_params" to customize
   649     Sledgehammer's behavior.  See the manual for details.
   650   - Modified the Isar proof reconstruction code so that it produces
   651     direct proofs rather than proofs by contradiction.  (This feature
   652     is still experimental.)
   653   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
   654     full-typed mode.
   655   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
   656 
   657 * Nitpick:
   658   - Added and implemented "binary_ints" and "bits" options.
   659   - Added "std" option and implemented support for nonstandard models.
   660   - Added and implemented "finitize" option to improve the precision
   661     of infinite datatypes based on a monotonicity analysis.
   662   - Added support for quotient types.
   663   - Added support for "specification" and "ax_specification"
   664     constructs.
   665   - Added support for local definitions (for "function" and
   666     "termination" proofs).
   667   - Added support for term postprocessors.
   668   - Optimized "Multiset.multiset" and "FinFun.finfun".
   669   - Improved efficiency of "destroy_constrs" optimization.
   670   - Fixed soundness bugs related to "destroy_constrs" optimization and
   671     record getters.
   672   - Fixed soundness bug related to higher-order constructors.
   673   - Fixed soundness bug when "full_descrs" is enabled.
   674   - Improved precision of set constructs.
   675   - Added "atoms" option.
   676   - Added cache to speed up repeated Kodkod invocations on the same
   677     problems.
   678   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
   679     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
   680     "SAT4J_Light".  INCOMPATIBILITY.
   681   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
   682     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
   683   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
   684 
   685 * Method "induct" now takes instantiations of the form t, where t is not
   686   a variable, as a shorthand for "x == t", where x is a fresh variable.
   687   If this is not intended, t has to be enclosed in parentheses.
   688   By default, the equalities generated by definitional instantiations
   689   are pre-simplified, which may cause parameters of inductive cases
   690   to disappear, or may even delete some of the inductive cases.
   691   Use "induct (no_simp)" instead of "induct" to restore the old
   692   behaviour. The (no_simp) option is also understood by the "cases"
   693   and "nominal_induct" methods, which now perform pre-simplification, too.
   694   INCOMPATIBILITY.
   695 
   696 
   697 *** HOLCF ***
   698 
   699 * Variable names in lemmas generated by the domain package have
   700 changed; the naming scheme is now consistent with the HOL datatype
   701 package.  Some proof scripts may be affected, INCOMPATIBILITY.
   702 
   703 * The domain package no longer defines the function "foo_copy" for
   704 recursive domain "foo".  The reach lemma is now stated directly in
   705 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
   706 be reformulated in terms of "foo_take", INCOMPATIBILITY.
   707 
   708 * Most definedness lemmas generated by the domain package (previously
   709 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
   710 like "foo$x = UU <-> x = UU", which works better as a simp rule.
   711 Proofs that used definedness lemmas as intro rules may break,
   712 potential INCOMPATIBILITY.
   713 
   714 * Induction and casedist rules generated by the domain package now
   715 declare proper case_names (one called "bottom", and one named for each
   716 constructor).  INCOMPATIBILITY.
   717 
   718 * For mutually-recursive domains, separate "reach" and "take_lemma"
   719 rules are generated for each domain, INCOMPATIBILITY.
   720 
   721   foo_bar.reach       ~> foo.reach  bar.reach
   722   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
   723 
   724 * Some lemmas generated by the domain package have been renamed for
   725 consistency with the datatype package, INCOMPATIBILITY.
   726 
   727   foo.ind        ~> foo.induct
   728   foo.finite_ind ~> foo.finite_induct
   729   foo.coind      ~> foo.coinduct
   730   foo.casedist   ~> foo.exhaust
   731   foo.exhaust    ~> foo.nchotomy
   732 
   733 * For consistency with other definition packages, the fixrec package
   734 now generates qualified theorem names, INCOMPATIBILITY.
   735 
   736   foo_simps  ~> foo.simps
   737   foo_unfold ~> foo.unfold
   738   foo_induct ~> foo.induct
   739 
   740 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
   741 method and internal fixrec proofs now use the default simpset instead.
   742 INCOMPATIBILITY.
   743 
   744 * The "contlub" predicate has been removed.  Proof scripts should use
   745 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
   746 
   747 * The "admw" predicate has been removed, INCOMPATIBILITY.
   748 
   749 * The constants cpair, cfst, and csnd have been removed in favor of
   750 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
   751 
   752 
   753 *** ML ***
   754 
   755 * Antiquotations for basic formal entities:
   756 
   757     @{class NAME}         -- type class
   758     @{class_syntax NAME}  -- syntax representation of the above
   759 
   760     @{type_name NAME}     -- logical type
   761     @{type_abbrev NAME}   -- type abbreviation
   762     @{nonterminal NAME}   -- type of concrete syntactic category
   763     @{type_syntax NAME}   -- syntax representation of any of the above
   764 
   765     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
   766     @{const_abbrev NAME}  -- abbreviated constant
   767     @{const_syntax NAME}  -- syntax representation of any of the above
   768 
   769 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
   770 syntax constant (cf. 'syntax' command).
   771 
   772 * Antiquotation @{make_string} inlines a function to print arbitrary
   773 values similar to the ML toplevel.  The result is compiler dependent
   774 and may fall back on "?" in certain situations.
   775 
   776 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
   777 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
   778 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
   779 not work with the asynchronous Isar document model.
   780 
   781 * Configuration options now admit dynamic default values, depending on
   782 the context or even global references.
   783 
   784 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
   785 uses an efficient external library if available (for Poly/ML).
   786 
   787 * Renamed some important ML structures, while keeping the old names
   788 for some time as aliases within the structure Legacy:
   789 
   790   OuterKeyword  ~>  Keyword
   791   OuterLex      ~>  Token
   792   OuterParse    ~>  Parse
   793   OuterSyntax   ~>  Outer_Syntax
   794   PrintMode     ~>  Print_Mode
   795   SpecParse     ~>  Parse_Spec
   796   ThyInfo       ~>  Thy_Info
   797   ThyLoad       ~>  Thy_Load
   798   ThyOutput     ~>  Thy_Output
   799   TypeInfer     ~>  Type_Infer
   800 
   801 Note that "open Legacy" simplifies porting of sources, but forgetting
   802 to remove it again will complicate porting again in the future.
   803 
   804 * Most operations that refer to a global context are named
   805 accordingly, e.g. Simplifier.global_context or
   806 ProofContext.init_global.  There are some situations where a global
   807 context actually works, but under normal circumstances one needs to
   808 pass the proper local context through the code!
   809 
   810 * Discontinued old TheoryDataFun with its copy/init operation -- data
   811 needs to be pure.  Functor Theory_Data_PP retains the traditional
   812 Pretty.pp argument to merge, which is absent in the standard
   813 Theory_Data version.
   814 
   815 * Sorts.certify_sort and derived "cert" operations for types and terms
   816 no longer minimize sorts.  Thus certification at the boundary of the
   817 inference kernel becomes invariant under addition of class relations,
   818 which is an important monotonicity principle.  Sorts are now minimized
   819 in the syntax layer only, at the boundary between the end-user and the
   820 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
   821 explicitly in rare situations.
   822 
   823 * Renamed old-style Drule.standard to Drule.export_without_context, to
   824 emphasize that this is in no way a standard operation.
   825 INCOMPATIBILITY.
   826 
   827 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
   828 usual for resolution.  Rare INCOMPATIBILITY.
   829 
   830 * Renamed varify/unvarify operations to varify_global/unvarify_global
   831 to emphasize that these only work in a global situation (which is
   832 quite rare).
   833 
   834 * Curried take and drop in library.ML; negative length is interpreted
   835 as infinity (as in chop).  Subtle INCOMPATIBILITY.
   836 
   837 * Proof terms: type substitutions on proof constants now use canonical
   838 order of type variables.  INCOMPATIBILITY for tools working with proof
   839 terms.
   840 
   841 * Raw axioms/defs may no longer carry sort constraints, and raw defs
   842 may no longer carry premises.  User-level specifications are
   843 transformed accordingly by Thm.add_axiom/add_def.
   844 
   845 
   846 *** System ***
   847 
   848 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
   849 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
   850 proof terms are enabled unconditionally in the new HOL-Proofs image.
   851 
   852 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
   853 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
   854 respectively.
   855 
   856 * Old lib/scripts/polyml-platform is superseded by the
   857 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
   858 variant, even on a 64 bit machine.  The following example setting
   859 prefers 64 bit if available:
   860 
   861   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
   862 
   863 * The preliminary Isabelle/jEdit application demonstrates the emerging
   864 Isabelle/Scala layer for advanced prover interaction and integration.
   865 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
   866 component.
   867 
   868 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
   869 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
   870 similar to the default assignment of the document preparation system
   871 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
   872 provides some operations for direct access to the font without asking
   873 the user for manual installation.
   874 
   875 
   876 
   877 New in Isabelle2009-1 (December 2009)
   878 -------------------------------------
   879 
   880 *** General ***
   881 
   882 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
   883 one backslash should be used, even in ML sources.
   884 
   885 
   886 *** Pure ***
   887 
   888 * Locale interpretation propagates mixins along the locale hierarchy.
   889 The currently only available mixins are the equations used to map
   890 local definitions to terms of the target domain of an interpretation.
   891 
   892 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
   893 loc" to print all interpretations of locale "loc" in the theory.
   894 Interpretations in proofs are not shown.
   895 
   896 * Thoroughly revised locales tutorial.  New section on conditional
   897 interpretation.
   898 
   899 * On instantiation of classes, remaining undefined class parameters
   900 are formally declared.  INCOMPATIBILITY.
   901 
   902 
   903 *** Document preparation ***
   904 
   905 * New generalized style concept for printing terms: @{foo (style) ...}
   906 instead of @{foo_style style ...}  (old form is still retained for
   907 backward compatibility).  Styles can be also applied for
   908 antiquotations prop, term_type and typeof.
   909 
   910 
   911 *** HOL ***
   912 
   913 * New proof method "smt" for a combination of first-order logic with
   914 equality, linear and nonlinear (natural/integer/real) arithmetic, and
   915 fixed-size bitvectors; there is also basic support for higher-order
   916 features (esp. lambda abstractions).  It is an incomplete decision
   917 procedure based on external SMT solvers using the oracle mechanism;
   918 for the SMT solver Z3, this method is proof-producing.  Certificates
   919 are provided to avoid calling the external solvers solely for
   920 re-checking proofs.  Due to a remote SMT service there is no need for
   921 installing SMT solvers locally.  See src/HOL/SMT.
   922 
   923 * New commands to load and prove verification conditions generated by
   924 the Boogie program verifier or derived systems (e.g. the Verifying C
   925 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
   926 
   927 * New counterexample generator tool 'nitpick' based on the Kodkod
   928 relational model finder.  See src/HOL/Tools/Nitpick and
   929 src/HOL/Nitpick_Examples.
   930 
   931 * New commands 'code_pred' and 'values' to invoke the predicate
   932 compiler and to enumerate values of inductive predicates.
   933 
   934 * A tabled implementation of the reflexive transitive closure.
   935 
   936 * New implementation of quickcheck uses generic code generator;
   937 default generators are provided for all suitable HOL types, records
   938 and datatypes.  Old quickcheck can be re-activated importing theory
   939 Library/SML_Quickcheck.
   940 
   941 * New testing tool Mirabelle for automated proof tools.  Applies
   942 several tools and tactics like sledgehammer, metis, or quickcheck, to
   943 every proof step in a theory.  To be used in batch mode via the
   944 "mirabelle" utility.
   945 
   946 * New proof method "sos" (sum of squares) for nonlinear real
   947 arithmetic (originally due to John Harison). It requires theory
   948 Library/Sum_Of_Squares.  It is not a complete decision procedure but
   949 works well in practice on quantifier-free real arithmetic with +, -,
   950 *, ^, =, <= and <, i.e. boolean combinations of equalities and
   951 inequalities between polynomials.  It makes use of external
   952 semidefinite programming solvers.  Method "sos" generates a
   953 certificate that can be pasted into the proof thus avoiding the need
   954 to call an external tool every time the proof is checked.  See
   955 src/HOL/Library/Sum_Of_Squares.
   956 
   957 * New method "linarith" invokes existing linear arithmetic decision
   958 procedure only.
   959 
   960 * New command 'atp_minimal' reduces result produced by Sledgehammer.
   961 
   962 * New Sledgehammer option "Full Types" in Proof General settings menu.
   963 Causes full type information to be output to the ATPs.  This slows
   964 ATPs down considerably but eliminates a source of unsound "proofs"
   965 that fail later.
   966 
   967 * New method "metisFT": A version of metis that uses full type
   968 information in order to avoid failures of proof reconstruction.
   969 
   970 * New evaluator "approximate" approximates an real valued term using
   971 the same method as the approximation method.
   972 
   973 * Method "approximate" now supports arithmetic expressions as
   974 boundaries of intervals and implements interval splitting and Taylor
   975 series expansion.
   976 
   977 * ML antiquotation @{code_datatype} inserts definition of a datatype
   978 generated by the code generator; e.g. see src/HOL/Predicate.thy.
   979 
   980 * New theory SupInf of the supremum and infimum operators for sets of
   981 reals.
   982 
   983 * New theory Probability, which contains a development of measure
   984 theory, eventually leading to Lebesgue integration and probability.
   985 
   986 * Extended Multivariate Analysis to include derivation and Brouwer's
   987 fixpoint theorem.
   988 
   989 * Reorganization of number theory, INCOMPATIBILITY:
   990   - new number theory development for nat and int, in theories Divides
   991     and GCD as well as in new session Number_Theory
   992   - some constants and facts now suffixed with _nat and _int
   993     accordingly
   994   - former session NumberTheory now named Old_Number_Theory, including
   995     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
   996   - moved theory Pocklington from src/HOL/Library to
   997     src/HOL/Old_Number_Theory
   998 
   999 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1000 lcm of finite and infinite sets. It is shown that they form a complete
  1001 lattice.
  1002 
  1003 * Class semiring_div requires superclass no_zero_divisors and proof of
  1004 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1005 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1006 generalized to class semiring_div, subsuming former theorems
  1007 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1008 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1009 INCOMPATIBILITY.
  1010 
  1011 * Refinements to lattice classes and sets:
  1012   - less default intro/elim rules in locale variant, more default
  1013     intro/elim rules in class variant: more uniformity
  1014   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1015     le_inf_iff
  1016   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1017     sup_aci)
  1018   - renamed ACI to inf_sup_aci
  1019   - new class "boolean_algebra"
  1020   - class "complete_lattice" moved to separate theory
  1021     "Complete_Lattice"; corresponding constants (and abbreviations)
  1022     renamed and with authentic syntax:
  1023     Set.Inf ~>    Complete_Lattice.Inf
  1024     Set.Sup ~>    Complete_Lattice.Sup
  1025     Set.INFI ~>   Complete_Lattice.INFI
  1026     Set.SUPR ~>   Complete_Lattice.SUPR
  1027     Set.Inter ~>  Complete_Lattice.Inter
  1028     Set.Union ~>  Complete_Lattice.Union
  1029     Set.INTER ~>  Complete_Lattice.INTER
  1030     Set.UNION ~>  Complete_Lattice.UNION
  1031   - authentic syntax for
  1032     Set.Pow
  1033     Set.image
  1034   - mere abbreviations:
  1035     Set.empty               (for bot)
  1036     Set.UNIV                (for top)
  1037     Set.inter               (for inf, formerly Set.Int)
  1038     Set.union               (for sup, formerly Set.Un)
  1039     Complete_Lattice.Inter  (for Inf)
  1040     Complete_Lattice.Union  (for Sup)
  1041     Complete_Lattice.INTER  (for INFI)
  1042     Complete_Lattice.UNION  (for SUPR)
  1043   - object-logic definitions as far as appropriate
  1044 
  1045 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1046 Un_subset_iff are explicitly deleted as default simp rules; then also
  1047 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1048 deleted to achieve the desired effect.
  1049 
  1050 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1051 rules by default any longer; the same applies to min_max.inf_absorb1
  1052 etc.  INCOMPATIBILITY.
  1053 
  1054 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1055 pred_set_conv by default.  INCOMPATIBILITY.
  1056 
  1057 * Power operations on relations and functions are now one dedicated
  1058 constant "compow" with infix syntax "^^".  Power operation on
  1059 multiplicative monoids retains syntax "^" and is now defined generic
  1060 in class power.  INCOMPATIBILITY.
  1061 
  1062 * Relation composition "R O S" now has a more standard argument order:
  1063 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1064 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1065 break, since the O_assoc rule was not rewritten like this.  Fix using
  1066 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1067 
  1068 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1069 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1070 INCOMPATIBILITY.
  1071 
  1072 * Most rules produced by inductive and datatype package have mandatory
  1073 prefixes.  INCOMPATIBILITY.
  1074 
  1075 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1076 the attribute of the same name.  Each of the theorems in the list
  1077 DERIV_intros assumes composition with an additional function and
  1078 matches a variable to the derivative, which has to be solved by the
  1079 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1080 of most elementary terms.  Former Maclauren.DERIV_tac and
  1081 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1082 INCOMPATIBILITY.
  1083 
  1084 * Code generator attributes follow the usual underscore convention:
  1085     code_unfold     replaces    code unfold
  1086     code_post       replaces    code post
  1087     etc.
  1088   INCOMPATIBILITY.
  1089 
  1090 * Renamed methods:
  1091     sizechange -> size_change
  1092     induct_scheme -> induction_schema
  1093   INCOMPATIBILITY.
  1094 
  1095 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1096 INCOMPATIBILITY, use "undefined" directly.
  1097 
  1098 * Renamed theorems:
  1099     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1100     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1101     Suc_plus1 -> Suc_eq_plus1
  1102     *anti_sym -> *antisym*
  1103     vector_less_eq_def -> vector_le_def
  1104   INCOMPATIBILITY.
  1105 
  1106 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1107 INCOMPATIBILITY.
  1108 
  1109 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1110 INCOMPATIBILITY.
  1111 
  1112 
  1113 *** HOLCF ***
  1114 
  1115 * Theory Representable defines a class "rep" of domains that are
  1116 representable (via an ep-pair) in the universal domain type "udom".
  1117 Instances are provided for all type constructors defined in HOLCF.
  1118 
  1119 * The 'new_domain' command is a purely definitional version of the
  1120 domain package, for representable domains.  Syntax is identical to the
  1121 old domain package.  The 'new_domain' package also supports indirect
  1122 recursion using previously-defined type constructors.  See
  1123 src/HOLCF/ex/New_Domain.thy for examples.
  1124 
  1125 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1126 on the left-hand side of an equation, and then performs
  1127 simplification.  Rewriting is done using rules declared with the
  1128 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1129 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1130 
  1131 * The pattern-match compiler in 'fixrec' can now handle constructors
  1132 with HOL function types.  Pattern-match combinators for the Pair
  1133 constructor are pre-configured.
  1134 
  1135 * The 'fixrec' package now produces better fixed-point induction rules
  1136 for mutually-recursive definitions:  Induction rules have conclusions
  1137 of the form "P foo bar" instead of "P <foo, bar>".
  1138 
  1139 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1140 been renamed to "below".  The name "below" now replaces "less" in many
  1141 theorem names.  (Legacy theorem names using "less" are still supported
  1142 as well.)
  1143 
  1144 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1145 patterns can be used to generate strictness rules, or to make
  1146 functions more strict (much like the bang-patterns supported by the
  1147 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1148 examples.
  1149 
  1150 
  1151 *** ML ***
  1152 
  1153 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1154 errors and run-time exceptions, including detailed source positions.
  1155 
  1156 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1157 identified entries, with some additional information such as source
  1158 position, logical grouping etc.
  1159 
  1160 * Theory and context data is now introduced by the simplified and
  1161 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1162 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1163 copy operation) is still available for some time.
  1164 
  1165 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1166 provides a high-level programming interface to synchronized state
  1167 variables with atomic update.  This works via pure function
  1168 application within a critical section -- its runtime should be as
  1169 short as possible; beware of deadlocks if critical code is nested,
  1170 either directly or indirectly via other synchronized variables!
  1171 
  1172 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1173 wraps raw ML references, explicitly indicating their non-thread-safe
  1174 behaviour.  The Isar toplevel keeps this structure open, to
  1175 accommodate Proof General as well as quick and dirty interactive
  1176 experiments with references.
  1177 
  1178 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1179 parallel tactical reasoning.
  1180 
  1181 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1182 are similar to SUBPROOF, but are slightly more flexible: only the
  1183 specified parts of the subgoal are imported into the context, and the
  1184 body tactic may introduce new subgoals and schematic variables.
  1185 
  1186 * Old tactical METAHYPS, which does not observe the proof context, has
  1187 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1188 or Subgoal.FOCUS etc.
  1189 
  1190 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1191 functors have their own ML name space there is no point to mark them
  1192 separately.)  Minor INCOMPATIBILITY.
  1193 
  1194 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1195 
  1196 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1197 INCOMPATIBILITY.
  1198 
  1199 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1200 mode, which avoids critical setmp.
  1201 
  1202 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1203 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1204 Attrib/Method.setup introduced in Isabelle2009.
  1205 
  1206 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1207 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1208 last resort.  INCOMPATIBILITY.
  1209 
  1210 * Display.pretty_thm now requires a proper context (cf. former
  1211 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1212 or even Display.pretty_thm_without_context as last resort.
  1213 INCOMPATIBILITY.
  1214 
  1215 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1216 Syntax.pretty_typ/term directly, preferably with proper context
  1217 instead of global theory.
  1218 
  1219 
  1220 *** System ***
  1221 
  1222 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1223 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1224 usedir option -q.
  1225 
  1226 * Support for additional "Isabelle components" via etc/components, see
  1227 also the system manual.
  1228 
  1229 * The isabelle makeall tool now operates on all components with
  1230 IsaMakefile, not just hardwired "logics".
  1231 
  1232 * Removed "compress" option from isabelle-process and isabelle usedir;
  1233 this is always enabled.
  1234 
  1235 * Discontinued support for Poly/ML 4.x versions.
  1236 
  1237 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  1238 on a given logic image.  This requires the lighttpd webserver and is
  1239 currently supported on Linux only.
  1240 
  1241 
  1242 
  1243 New in Isabelle2009 (April 2009)
  1244 --------------------------------
  1245 
  1246 *** General ***
  1247 
  1248 * Simplified main Isabelle executables, with less surprises on
  1249 case-insensitive file-systems (such as Mac OS).
  1250 
  1251   - The main Isabelle tool wrapper is now called "isabelle" instead of
  1252     "isatool."
  1253 
  1254   - The former "isabelle" alias for "isabelle-process" has been
  1255     removed (should rarely occur to regular users).
  1256 
  1257   - The former "isabelle-interface" and its alias "Isabelle" have been
  1258     removed (interfaces are now regular Isabelle tools).
  1259 
  1260 Within scripts and make files, the Isabelle environment variables
  1261 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  1262 respectively.  (The latter are still available as legacy feature.)
  1263 
  1264 The old isabelle-interface wrapper could react in confusing ways if
  1265 the interface was uninstalled or changed otherwise.  Individual
  1266 interface tool configuration is now more explicit, see also the
  1267 Isabelle system manual.  In particular, Proof General is now available
  1268 via "isabelle emacs".
  1269 
  1270 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  1271 purge installed copies of Isabelle executables and re-run "isabelle
  1272 install -p ...", or use symlinks.
  1273 
  1274 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  1275 old ~/isabelle, which was slightly non-standard and apt to cause
  1276 surprises on case-insensitive file-systems (such as Mac OS).
  1277 
  1278 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  1279 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  1280 care is required when using older releases of Isabelle.  Note that
  1281 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  1282 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  1283 
  1284 * Proofs of fully specified statements are run in parallel on
  1285 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  1286 a regular 4-core machine, if the initial heap space is made reasonably
  1287 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  1288 
  1289 * The main reference manuals ("isar-ref", "implementation", and
  1290 "system") have been updated and extended.  Formally checked references
  1291 as hyperlinks are now available uniformly.
  1292 
  1293 
  1294 *** Pure ***
  1295 
  1296 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  1297 respects.  The most important changes are listed below.  See the
  1298 Tutorial on Locales ("locales" manual) for details.
  1299 
  1300 - In locale expressions, instantiation replaces renaming.  Parameters
  1301 must be declared in a for clause.  To aid compatibility with previous
  1302 parameter inheritance, in locale declarations, parameters that are not
  1303 'touched' (instantiation position "_" or omitted) are implicitly added
  1304 with their syntax at the beginning of the for clause.
  1305 
  1306 - Syntax from abbreviations and definitions in locales is available in
  1307 locale expressions and context elements.  The latter is particularly
  1308 useful in locale declarations.
  1309 
  1310 - More flexible mechanisms to qualify names generated by locale
  1311 expressions.  Qualifiers (prefixes) may be specified in locale
  1312 expressions, and can be marked as mandatory (syntax: "name!:") or
  1313 optional (syntax "name?:").  The default depends for plain "name:"
  1314 depends on the situation where a locale expression is used: in
  1315 commands 'locale' and 'sublocale' prefixes are optional, in
  1316 'interpretation' and 'interpret' prefixes are mandatory.  The old
  1317 implicit qualifiers derived from the parameter names of a locale are
  1318 no longer generated.
  1319 
  1320 - Command "sublocale l < e" replaces "interpretation l < e".  The
  1321 instantiation clause in "interpretation" and "interpret" (square
  1322 brackets) is no longer available.  Use locale expressions.
  1323 
  1324 - When converting proof scripts, mandatory qualifiers in
  1325 'interpretation' and 'interpret' should be retained by default, even
  1326 if this is an INCOMPATIBILITY compared to former behavior.  In the
  1327 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  1328 in locale expressions range over a single locale instance only.
  1329 
  1330 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  1331 In existing theorem specifications replace the includes element by the
  1332 respective context elements of the included locale, omitting those
  1333 that are already present in the theorem specification.  Multiple
  1334 assume elements of a locale should be replaced by a single one
  1335 involving the locale predicate.  In the proof body, declarations (most
  1336 notably theorems) may be regained by interpreting the respective
  1337 locales in the proof context as required (command "interpret").
  1338 
  1339 If using "includes" in replacement of a target solely because the
  1340 parameter types in the theorem are not as general as in the target,
  1341 consider declaring a new locale with additional type constraints on
  1342 the parameters (context element "constrains").
  1343 
  1344 - Discontinued "locale (open)".  INCOMPATIBILITY.
  1345 
  1346 - Locale interpretation commands no longer attempt to simplify goal.
  1347 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  1348 methods intro_locales and unfold_locales to clarify.
  1349 
  1350 - Locale interpretation commands no longer accept interpretation
  1351 attributes.  INCOMPATIBILITY.
  1352 
  1353 * Class declaration: so-called "base sort" must not be given in import
  1354 list any longer, but is inferred from the specification.  Particularly
  1355 in HOL, write
  1356 
  1357     class foo = ...
  1358 
  1359 instead of
  1360 
  1361     class foo = type + ...
  1362 
  1363 * Class target: global versions of theorems stemming do not carry a
  1364 parameter prefix any longer.  INCOMPATIBILITY.
  1365 
  1366 * Class 'instance' command no longer accepts attached definitions.
  1367 INCOMPATIBILITY, use proper 'instantiation' target instead.
  1368 
  1369 * Recovered hiding of consts, which was accidentally broken in
  1370 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  1371 makes c inaccessible; consider using ``hide (open) const c'' instead.
  1372 
  1373 * Slightly more coherent Pure syntax, with updated documentation in
  1374 isar-ref manual.  Removed locales meta_term_syntax and
  1375 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  1376 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  1377 directly in regular applications.
  1378 
  1379 * There is a new syntactic category "float_const" for signed decimal
  1380 fractions (e.g. 123.45 or -123.45).
  1381 
  1382 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  1383 interface with 'setup' command instead.
  1384 
  1385 * Command 'local_setup' is similar to 'setup', but operates on a local
  1386 theory context.
  1387 
  1388 * The 'axiomatization' command now only works within a global theory
  1389 context.  INCOMPATIBILITY.
  1390 
  1391 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  1392 hypotheses.  Sorts required in the course of reasoning need to be
  1393 covered by the constraints in the initial statement, completed by the
  1394 type instance information of the background theory.  Non-trivial sort
  1395 hypotheses, which rarely occur in practice, may be specified via
  1396 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  1397 
  1398   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  1399 
  1400 The result contains an implicit sort hypotheses as before --
  1401 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  1402 normalization.
  1403 
  1404 * Generalized Isar history, with support for linear undo, direct state
  1405 addressing etc.
  1406 
  1407 * Changed defaults for unify configuration options:
  1408 
  1409   unify_trace_bound = 50 (formerly 25)
  1410   unify_search_bound = 60 (formerly 30)
  1411 
  1412 * Different bookkeeping for code equations (INCOMPATIBILITY):
  1413 
  1414   a) On theory merge, the last set of code equations for a particular
  1415      constant is taken (in accordance with the policy applied by other
  1416      parts of the code generator framework).
  1417 
  1418   b) Code equations stemming from explicit declarations (e.g. code
  1419      attribute) gain priority over default code equations stemming
  1420      from definition, primrec, fun etc.
  1421 
  1422 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  1423 
  1424 * Unified theorem tables for both code generators.  Thus [code
  1425 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  1426 
  1427 * Command 'find_consts' searches for constants based on type and name
  1428 patterns, e.g.
  1429 
  1430     find_consts "_ => bool"
  1431 
  1432 By default, matching is against subtypes, but it may be restricted to
  1433 the whole type.  Searching by name is possible.  Multiple queries are
  1434 conjunctive and queries may be negated by prefixing them with a
  1435 hyphen:
  1436 
  1437     find_consts strict: "_ => bool" name: "Int" -"int => int"
  1438 
  1439 * New 'find_theorems' criterion "solves" matches theorems that
  1440 directly solve the current goal (modulo higher-order unification).
  1441 
  1442 * Auto solve feature for main theorem statements: whenever a new goal
  1443 is stated, "find_theorems solves" is called; any theorems that could
  1444 solve the lemma directly are listed as part of the goal state.
  1445 Cf. associated options in Proof General Isabelle settings menu,
  1446 enabled by default, with reasonable timeout for pathological cases of
  1447 higher-order unification.
  1448 
  1449 
  1450 *** Document preparation ***
  1451 
  1452 * Antiquotation @{lemma} now imitates a regular terminal proof,
  1453 demanding keyword 'by' and supporting the full method expression
  1454 syntax just like the Isar command 'by'.
  1455 
  1456 
  1457 *** HOL ***
  1458 
  1459 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  1460 points Main and Complex_Main remain as before.
  1461 
  1462 * Logic image HOL-Plain provides a minimal HOL with the most important
  1463 tools available (inductive, datatype, primrec, ...).  This facilitates
  1464 experimentation and tool development.  Note that user applications
  1465 (and library theories) should never refer to anything below theory
  1466 Main, as before.
  1467 
  1468 * Logic image HOL-Main stops at theory Main, and thus facilitates
  1469 experimentation due to shorter build times.
  1470 
  1471 * Logic image HOL-NSA contains theories of nonstandard analysis which
  1472 were previously part of former HOL-Complex.  Entry point Hyperreal
  1473 remains valid, but theories formerly using Complex_Main should now use
  1474 new entry point Hypercomplex.
  1475 
  1476 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  1477 Posix processes.  Avoids potentially expensive forking of the ML
  1478 process.  New thread-based implementation also works on non-Unix
  1479 platforms (Cygwin).  Provers are no longer hardwired, but defined
  1480 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  1481 commands are covered in the isar-ref manual.
  1482 
  1483 * Wrapper scripts for remote SystemOnTPTP service allows to use
  1484 sledgehammer without local ATP installation (Vampire etc.). Other
  1485 provers may be included via suitable ML wrappers, see also
  1486 src/HOL/ATP_Linkup.thy.
  1487 
  1488 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  1489 menu.
  1490 
  1491 * The metis method no longer fails because the theorem is too trivial
  1492 (contains the empty clause).
  1493 
  1494 * The metis method now fails in the usual manner, rather than raising
  1495 an exception, if it determines that it cannot prove the theorem.
  1496 
  1497 * Method "coherent" implements a prover for coherent logic (see also
  1498 src/Tools/coherent.ML).
  1499 
  1500 * Constants "undefined" and "default" replace "arbitrary".  Usually
  1501 "undefined" is the right choice to replace "arbitrary", though
  1502 logically there is no difference.  INCOMPATIBILITY.
  1503 
  1504 * Command "value" now integrates different evaluation mechanisms.  The
  1505 result of the first successful evaluation mechanism is printed.  In
  1506 square brackets a particular named evaluation mechanisms may be
  1507 specified (currently, [SML], [code] or [nbe]).  See further
  1508 src/HOL/ex/Eval_Examples.thy.
  1509 
  1510 * Normalization by evaluation now allows non-leftlinear equations.
  1511 Declare with attribute [code nbe].
  1512 
  1513 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  1514 as the structured Isar versions "cases" and "induct", cf. the
  1515 corresponding "cases" and "induct" attributes.  Mutual induction rules
  1516 are now presented as a list of individual projections
  1517 (e.g. foo_bar.inducts for types foo and bar); the old format with
  1518 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  1519 rare situations a different rule is selected --- notably nested tuple
  1520 elimination instead of former prod.exhaust: use explicit (case_tac t
  1521 rule: prod.exhaust) here.
  1522 
  1523 * Attributes "cases", "induct", "coinduct" support "del" option.
  1524 
  1525 * Removed fact "case_split_thm", which duplicates "case_split".
  1526 
  1527 * The option datatype has been moved to a new theory Option.  Renamed
  1528 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  1529 
  1530 * New predicate "strict_mono" classifies strict functions on partial
  1531 orders.  With strict functions on linear orders, reasoning about
  1532 (in)equalities is facilitated by theorems "strict_mono_eq",
  1533 "strict_mono_less_eq" and "strict_mono_less".
  1534 
  1535 * Some set operations are now proper qualified constants with
  1536 authentic syntax.  INCOMPATIBILITY:
  1537 
  1538     op Int ~>   Set.Int
  1539     op Un ~>    Set.Un
  1540     INTER ~>    Set.INTER
  1541     UNION ~>    Set.UNION
  1542     Inter ~>    Set.Inter
  1543     Union ~>    Set.Union
  1544     {} ~>       Set.empty
  1545     UNIV ~>     Set.UNIV
  1546 
  1547 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  1548 theory Set.
  1549 
  1550 * Auxiliary class "itself" has disappeared -- classes without any
  1551 parameter are treated as expected by the 'class' command.
  1552 
  1553 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  1554 
  1555 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  1556 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  1557 
  1558 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  1559 method "approximation".  It proves formulas on real values by using
  1560 interval arithmetic.  In the formulas are also the transcendental
  1561 functions sin, cos, tan, atan, ln, exp and the constant pi are
  1562 allowed. For examples see
  1563 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  1564 
  1565 * Theory "Reflection" now resides in HOL/Library.
  1566 
  1567 * Entry point to Word library now simply named "Word".
  1568 INCOMPATIBILITY.
  1569 
  1570 * Made source layout more coherent with logical distribution
  1571 structure:
  1572 
  1573     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  1574     src/HOL/Library/Code_Message.thy ~> src/HOL/
  1575     src/HOL/Library/GCD.thy ~> src/HOL/
  1576     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  1577     src/HOL/Library/Parity.thy ~> src/HOL/
  1578     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  1579     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  1580     src/HOL/Real/Lubs.thy ~> src/HOL/
  1581     src/HOL/Real/PReal.thy ~> src/HOL/
  1582     src/HOL/Real/Rational.thy ~> src/HOL/
  1583     src/HOL/Real/RComplete.thy ~> src/HOL/
  1584     src/HOL/Real/RealDef.thy ~> src/HOL/
  1585     src/HOL/Real/RealPow.thy ~> src/HOL/
  1586     src/HOL/Real/Real.thy ~> src/HOL/
  1587     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  1588     src/HOL/Complex/Complex.thy ~> src/HOL/
  1589     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  1590     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  1591     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  1592     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  1593     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  1594     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  1595     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  1596     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  1597     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  1598     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  1599     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  1600     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  1601     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  1602     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  1603     src/HOL/Real/Float ~> src/HOL/Library/
  1604     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  1605     src/HOL/Real/RealVector.thy ~> src/HOL/
  1606 
  1607     src/HOL/arith_data.ML ~> src/HOL/Tools
  1608     src/HOL/hologic.ML ~> src/HOL/Tools
  1609     src/HOL/simpdata.ML ~> src/HOL/Tools
  1610     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  1611     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  1612     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  1613     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  1614     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  1615     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  1616     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  1617 
  1618     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  1619     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  1620     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  1621     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  1622     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  1623     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  1624 
  1625 * If methods "eval" and "evaluation" encounter a structured proof
  1626 state with !!/==>, only the conclusion is evaluated to True (if
  1627 possible), avoiding strange error messages.
  1628 
  1629 * Method "sizechange" automates termination proofs using (a
  1630 modification of) the size-change principle.  Requires SAT solver.  See
  1631 src/HOL/ex/Termination.thy for examples.
  1632 
  1633 * Simplifier: simproc for let expressions now unfolds if bound
  1634 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  1635 
  1636 * Method "arith": Linear arithmetic now ignores all inequalities when
  1637 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  1638 
  1639 * New attribute "arith" for facts that should always be used
  1640 automatically by arithmetic. It is intended to be used locally in
  1641 proofs, e.g.
  1642 
  1643   assumes [arith]: "x > 0"
  1644 
  1645 Global usage is discouraged because of possible performance impact.
  1646 
  1647 * New classes "top" and "bot" with corresponding operations "top" and
  1648 "bot" in theory Orderings; instantiation of class "complete_lattice"
  1649 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  1650 
  1651 * Changed definition lemma "less_fun_def" in order to provide an
  1652 instance for preorders on functions; use lemma "less_le" instead.
  1653 INCOMPATIBILITY.
  1654 
  1655 * Theory Orderings: class "wellorder" moved here, with explicit
  1656 induction rule "less_induct" as assumption.  For instantiation of
  1657 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  1658 INCOMPATIBILITY.
  1659 
  1660 * Theory Orderings: added class "preorder" as superclass of "order".
  1661 INCOMPATIBILITY: Instantiation proofs for order, linorder
  1662 etc. slightly changed.  Some theorems named order_class.* now named
  1663 preorder_class.*.
  1664 
  1665 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  1666 "diag" to "Id_on".
  1667 
  1668 * Theory Finite_Set: added a new fold combinator of type
  1669 
  1670   ('a => 'b => 'b) => 'b => 'a set => 'b
  1671 
  1672 Occasionally this is more convenient than the old fold combinator
  1673 which is now defined in terms of the new one and renamed to
  1674 fold_image.
  1675 
  1676 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  1677 and "ring_simps" have been replaced by "algebra_simps" (which can be
  1678 extended with further lemmas!).  At the moment both still exist but
  1679 the former will disappear at some point.
  1680 
  1681 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  1682 class recpower.  Type-specific simp rules for various recpower types
  1683 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  1684 
  1685 rat_power_0    -> power_0
  1686 rat_power_Suc  -> power_Suc
  1687 realpow_0      -> power_0
  1688 realpow_Suc    -> power_Suc
  1689 complexpow_0   -> power_0
  1690 complexpow_Suc -> power_Suc
  1691 power_poly_0   -> power_0
  1692 power_poly_Suc -> power_Suc
  1693 
  1694 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  1695 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  1696 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  1697 of lemmas from Divides has been generalized from nat to class
  1698 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  1699 renames resulting from duplicate elimination:
  1700 
  1701     dvd_def_mod ~>          dvd_eq_mod_eq_0
  1702     zero_dvd_iff ~>         dvd_0_left_iff
  1703     dvd_0 ~>                dvd_0_right
  1704     DIVISION_BY_ZERO_DIV ~> div_by_0
  1705     DIVISION_BY_ZERO_MOD ~> mod_by_0
  1706     mult_div ~>             div_mult_self2_is_id
  1707     mult_mod ~>             mod_mult_self2_is_0
  1708 
  1709 * Theory IntDiv: removed many lemmas that are instances of class-based
  1710 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  1711 rename old lemmas as follows:
  1712 
  1713 dvd_diff               -> nat_dvd_diff
  1714 dvd_zminus_iff         -> dvd_minus_iff
  1715 mod_add1_eq            -> mod_add_eq
  1716 mod_mult1_eq           -> mod_mult_right_eq
  1717 mod_mult1_eq'          -> mod_mult_left_eq
  1718 mod_mult_distrib_mod   -> mod_mult_eq
  1719 nat_mod_add_left_eq    -> mod_add_left_eq
  1720 nat_mod_add_right_eq   -> mod_add_right_eq
  1721 nat_mod_div_trivial    -> mod_div_trivial
  1722 nat_mod_mod_trivial    -> mod_mod_trivial
  1723 zdiv_zadd_self1        -> div_add_self1
  1724 zdiv_zadd_self2        -> div_add_self2
  1725 zdiv_zmult_self1       -> div_mult_self2_is_id
  1726 zdiv_zmult_self2       -> div_mult_self1_is_id
  1727 zdvd_triv_left         -> dvd_triv_left
  1728 zdvd_triv_right        -> dvd_triv_right
  1729 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  1730 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  1731 zmod_zadd_left_eq      -> mod_add_left_eq
  1732 zmod_zadd_right_eq     -> mod_add_right_eq
  1733 zmod_zadd_self1        -> mod_add_self1
  1734 zmod_zadd_self2        -> mod_add_self2
  1735 zmod_zadd1_eq          -> mod_add_eq
  1736 zmod_zdiff1_eq         -> mod_diff_eq
  1737 zmod_zdvd_zmod         -> mod_mod_cancel
  1738 zmod_zmod_cancel       -> mod_mod_cancel
  1739 zmod_zmult_self1       -> mod_mult_self2_is_0
  1740 zmod_zmult_self2       -> mod_mult_self1_is_0
  1741 zmod_1                 -> mod_by_1
  1742 zdiv_1                 -> div_by_1
  1743 zdvd_abs1              -> abs_dvd_iff
  1744 zdvd_abs2              -> dvd_abs_iff
  1745 zdvd_refl              -> dvd_refl
  1746 zdvd_trans             -> dvd_trans
  1747 zdvd_zadd              -> dvd_add
  1748 zdvd_zdiff             -> dvd_diff
  1749 zdvd_zminus_iff        -> dvd_minus_iff
  1750 zdvd_zminus2_iff       -> minus_dvd_iff
  1751 zdvd_zmultD            -> dvd_mult_right
  1752 zdvd_zmultD2           -> dvd_mult_left
  1753 zdvd_zmult_mono        -> mult_dvd_mono
  1754 zdvd_0_right           -> dvd_0_right
  1755 zdvd_0_left            -> dvd_0_left_iff
  1756 zdvd_1_left            -> one_dvd
  1757 zminus_dvd_iff         -> minus_dvd_iff
  1758 
  1759 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  1760 
  1761 * The real numbers offer decimal input syntax: 12.34 is translated
  1762 into 1234/10^2. This translation is not reversed upon output.
  1763 
  1764 * Theory Library/Polynomial defines an abstract type 'a poly of
  1765 univariate polynomials with coefficients of type 'a.  In addition to
  1766 the standard ring operations, it also supports div and mod.  Code
  1767 generation is also supported, using list-style constructors.
  1768 
  1769 * Theory Library/Inner_Product defines a class of real_inner for real
  1770 inner product spaces, with an overloaded operation inner :: 'a => 'a
  1771 => real.  Class real_inner is a subclass of real_normed_vector from
  1772 theory RealVector.
  1773 
  1774 * Theory Library/Product_Vector provides instances for the product
  1775 type 'a * 'b of several classes from RealVector and Inner_Product.
  1776 Definitions of addition, subtraction, scalar multiplication, norms,
  1777 and inner products are included.
  1778 
  1779 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  1780 addition to the field operations, numerals and case syntax are also
  1781 supported.
  1782 
  1783 * Theory Library/Diagonalize provides constructive version of Cantor's
  1784 first diagonalization argument.
  1785 
  1786 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  1787 zlcm (for int); carried together from various gcd/lcm developements in
  1788 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  1789 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  1790 may recover tupled syntax as follows:
  1791 
  1792     hide (open) const gcd
  1793     abbreviation gcd where
  1794       "gcd == (%(a, b). GCD.gcd a b)"
  1795     notation (output)
  1796       GCD.gcd ("gcd '(_, _')")
  1797 
  1798 The same works for lcm, zgcd, zlcm.
  1799 
  1800 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  1801 instantiations for algebraic structures.  Removed some duplicate
  1802 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  1803 
  1804 * ML antiquotation @{code} takes a constant as argument and generates
  1805 corresponding code in background and inserts name of the corresponding
  1806 resulting ML value/function/datatype constructor binding in place.
  1807 All occurrences of @{code} with a single ML block are generated
  1808 simultaneously.  Provides a generic and safe interface for
  1809 instrumentalizing code generation.  See
  1810 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  1811 In future you ought to refrain from ad-hoc compiling generated SML
  1812 code on the ML toplevel.  Note that (for technical reasons) @{code}
  1813 cannot refer to constants for which user-defined serializations are
  1814 set.  Refer to the corresponding ML counterpart directly in that
  1815 cases.
  1816 
  1817 * Command 'rep_datatype': instead of theorem names the command now
  1818 takes a list of terms denoting the constructors of the type to be
  1819 represented as datatype.  The characteristic theorems have to be
  1820 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  1821 have disappeared in favour of existing ones:
  1822 
  1823     unit_induct                 ~> unit.induct
  1824     prod_induct                 ~> prod.induct
  1825     sum_induct                  ~> sum.induct
  1826     Suc_Suc_eq                  ~> nat.inject
  1827     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  1828 
  1829 
  1830 *** HOL-Algebra ***
  1831 
  1832 * New locales for orders and lattices where the equivalence relation
  1833 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  1834 locales use a record structure with field eq for the equivalence.
  1835 
  1836 * New theory of factorial domains.
  1837 
  1838 * Units_l_inv and Units_r_inv are now simp rules by default.
  1839 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  1840 and/or r_inv will now also require deletion of these lemmas.
  1841 
  1842 * Renamed the following theorems, INCOMPATIBILITY:
  1843 
  1844 UpperD ~> Upper_memD
  1845 LowerD ~> Lower_memD
  1846 least_carrier ~> least_closed
  1847 greatest_carrier ~> greatest_closed
  1848 greatest_Lower_above ~> greatest_Lower_below
  1849 one_zero ~> carrier_one_zero
  1850 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  1851 
  1852 
  1853 *** HOL-Nominal ***
  1854 
  1855 * Nominal datatypes can now contain type-variables.
  1856 
  1857 * Commands 'nominal_inductive' and 'equivariance' work with local
  1858 theory targets.
  1859 
  1860 * Nominal primrec can now works with local theory targets and its
  1861 specification syntax now conforms to the general format as seen in
  1862 'inductive' etc.
  1863 
  1864 * Method "perm_simp" honours the standard simplifier attributes
  1865 (no_asm), (no_asm_use) etc.
  1866 
  1867 * The new predicate #* is defined like freshness, except that on the
  1868 left hand side can be a set or list of atoms.
  1869 
  1870 * Experimental command 'nominal_inductive2' derives strong induction
  1871 principles for inductive definitions.  In contrast to
  1872 'nominal_inductive', which can only deal with a fixed number of
  1873 binders, it can deal with arbitrary expressions standing for sets of
  1874 atoms to be avoided.  The only inductive definition we have at the
  1875 moment that needs this generalisation is the typing rule for Lets in
  1876 the algorithm W:
  1877 
  1878  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  1879  -----------------------------------------------------------------
  1880          Gamma |- Let x be t1 in t2 : T2
  1881 
  1882 In this rule one wants to avoid all the binders that are introduced by
  1883 "close Gamma T1".  We are looking for other examples where this
  1884 feature might be useful.  Please let us know.
  1885 
  1886 
  1887 *** HOLCF ***
  1888 
  1889 * Reimplemented the simplification procedure for proving continuity
  1890 subgoals.  The new simproc is extensible; users can declare additional
  1891 continuity introduction rules with the attribute [cont2cont].
  1892 
  1893 * The continuity simproc now uses a different introduction rule for
  1894 solving continuity subgoals on terms with lambda abstractions.  In
  1895 some rare cases the new simproc may fail to solve subgoals that the
  1896 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  1897 Potential INCOMPATIBILITY.
  1898 
  1899 * Command 'fixrec': specification syntax now conforms to the general
  1900 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  1901 examples.  INCOMPATIBILITY.
  1902 
  1903 
  1904 *** ZF ***
  1905 
  1906 * Proof of Zorn's Lemma for partial orders.
  1907 
  1908 
  1909 *** ML ***
  1910 
  1911 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  1912 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  1913 depends on multithreading, so timouts will not work before Poly/ML
  1914 5.2.1!
  1915 
  1916 * High-level support for concurrent ML programming, see
  1917 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  1918 particularly convenient to organize independent functional
  1919 computations.  The concept of "synchronized variables" provides a
  1920 higher-order interface for components with shared state, avoiding the
  1921 delicate details of mutexes and condition variables.  (Requires
  1922 Poly/ML 5.2.1 or later.)
  1923 
  1924 * ML bindings produced via Isar commands are stored within the Isar
  1925 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  1926 become thread-safe and work with undo as expected (concerning
  1927 top-level bindings, not side-effects on global references).
  1928 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  1929 compiler at runtime; really global bindings need to be given outside a
  1930 theory.  (Requires Poly/ML 5.2 or later.)
  1931 
  1932 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  1933 context.  Top-level ML bindings are stored within the proof context in
  1934 a purely sequential fashion, disregarding the nested proof structure.
  1935 ML bindings introduced by 'ML_prf' are discarded at the end of the
  1936 proof.  (Requires Poly/ML 5.2 or later.)
  1937 
  1938 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  1939 and Method.setup, as well as Isar commands 'attribute_setup' and
  1940 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  1941 existing code accordingly, or use plain 'setup' together with old
  1942 Method.add_method.
  1943 
  1944 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  1945 to 'a -> thm, while results are always tagged with an authentic oracle
  1946 name.  The Isar command 'oracle' is now polymorphic, no argument type
  1947 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  1948 accordingly.  Note that extra performance may be gained by producing
  1949 the cterm carefully, avoiding slow Thm.cterm_of.
  1950 
  1951 * Simplified interface for defining document antiquotations via
  1952 ThyOutput.antiquotation, ThyOutput.output, and optionally
  1953 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  1954 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  1955 examples.
  1956 
  1957 * More systematic treatment of long names, abstract name bindings, and
  1958 name space operations.  Basic operations on qualified names have been
  1959 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  1960 Long_Name.append.  Old type bstring has been mostly replaced by
  1961 abstract type binding (see structure Binding), which supports precise
  1962 qualification by packages and local theory targets, as well as proper
  1963 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  1964 bstring values into Binding.name, or better pass through abstract
  1965 bindings everywhere.  See further src/Pure/General/long_name.ML,
  1966 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  1967 
  1968 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  1969 LocalTheory.note etc.) now refer to the *full* internal name, not the
  1970 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  1971 
  1972 * Disposed old type and term read functions (Sign.read_def_typ,
  1973 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  1974 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  1975 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  1976 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  1977 resort for legacy applications.
  1978 
  1979 * Disposed old declarations, tactics, tactic combinators that refer to
  1980 the simpset or claset of an implicit theory (such as Addsimps,
  1981 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  1982 embedded ML text, or local_simpset_of with a proper context passed as
  1983 explicit runtime argument.
  1984 
  1985 * Rules and tactics that read instantiations (read_instantiate,
  1986 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  1987 context, which is required for parsing and type-checking.  Moreover,
  1988 the variables are specified as plain indexnames, not string encodings
  1989 thereof.  INCOMPATIBILITY.
  1990 
  1991 * Generic Toplevel.add_hook interface allows to analyze the result of
  1992 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  1993 for theorem dependency output of transactions resulting in a new
  1994 theory state.
  1995 
  1996 * ML antiquotations: block-structured compilation context indicated by
  1997 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  1998 
  1999   @{binding name}                         - basic name binding
  2000   @{let ?pat = term}                      - term abbreviation (HO matching)
  2001   @{note name = fact}                     - fact abbreviation
  2002   @{thm fact}                             - singleton fact (with attributes)
  2003   @{thms fact}                            - general fact (with attributes)
  2004   @{lemma prop by method}                 - singleton goal
  2005   @{lemma prop by meth1 meth2}            - singleton goal
  2006   @{lemma prop1 ... propN by method}      - general goal
  2007   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2008   @{lemma (open) ...}                     - open derivation
  2009 
  2010 
  2011 *** System ***
  2012 
  2013 * The Isabelle "emacs" tool provides a specific interface to invoke
  2014 Proof General / Emacs, with more explicit failure if that is not
  2015 installed (the old isabelle-interface script silently falls back on
  2016 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2017 installation location of the Proof General distribution.
  2018 
  2019 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2020 the Isabelle process into a JVM/Scala application.  See
  2021 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2022 process wrapper has been discontinued.)
  2023 
  2024 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2025 
  2026 * Various status messages (with exact source position information) are
  2027 emitted, if proper markup print mode is enabled.  This allows
  2028 user-interface components to provide detailed feedback on internal
  2029 prover operations.
  2030 
  2031 
  2032 
  2033 New in Isabelle2008 (June 2008)
  2034 -------------------------------
  2035 
  2036 *** General ***
  2037 
  2038 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2039 and updated, with formally checked references as hyperlinks.
  2040 
  2041 * Theory loader: use_thy (and similar operations) no longer set the
  2042 implicit ML context, which was occasionally hard to predict and in
  2043 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2044 provides a proper context already.
  2045 
  2046 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2047 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2048 'use' within a theory file will do the job.
  2049 
  2050 * Name space merge now observes canonical order, i.e. the second space
  2051 is inserted into the first one, while existing entries in the first
  2052 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2053 swap theory imports.
  2054 
  2055 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2056 INCOMPATIBILITY in identifier syntax etc.
  2057 
  2058 * Outer syntax: string tokens no longer admit escaped white space,
  2059 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2060 white space without escapes.
  2061 
  2062 * Outer syntax: string tokens may contain arbitrary character codes
  2063 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2064 "foo_bar".
  2065 
  2066 
  2067 *** Pure ***
  2068 
  2069 * Context-dependent token translations.  Default setup reverts locally
  2070 fixed variables, and adds hilite markup for undeclared frees.
  2071 
  2072 * Unused theorems can be found using the new command 'unused_thms'.
  2073 There are three ways of invoking it:
  2074 
  2075 (1) unused_thms
  2076      Only finds unused theorems in the current theory.
  2077 
  2078 (2) unused_thms thy_1 ... thy_n -
  2079      Finds unused theorems in the current theory and all of its ancestors,
  2080      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2081 
  2082 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2083      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2084      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2085      their ancestors.
  2086 
  2087 In order to increase the readability of the list produced by
  2088 unused_thms, theorems that have been created by a particular instance
  2089 of a theory command such as 'inductive' or 'function' are considered
  2090 to belong to the same "group", meaning that if at least one theorem in
  2091 this group is used, the other theorems in the same group are no longer
  2092 reported as unused.  Moreover, if all theorems in the group are
  2093 unused, only one theorem in the group is displayed.
  2094 
  2095 Note that proof objects have to be switched on in order for
  2096 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2097 usually the case when using Proof General with the default settings).
  2098 
  2099 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2100 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2101 duplicate fact bindings, or even accidental fact duplications.  Note
  2102 that tools may maintain dynamically scoped facts systematically, using
  2103 PureThy.add_thms_dynamic.
  2104 
  2105 * Command 'hide' now allows to hide from "fact" name space as well.
  2106 
  2107 * Eliminated destructive theorem database, simpset, claset, and
  2108 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2109 update of theories within ML code.
  2110 
  2111 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2112 INCOMPATIBILITY, object-logics depending on former Pure require
  2113 additional setup PureThy.old_appl_syntax_setup; object-logics
  2114 depending on former CPure need to refer to Pure.
  2115 
  2116 * Commands 'use' and 'ML' are now purely functional, operating on
  2117 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2118 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2119 INCOMPATIBILITY.
  2120 
  2121 * Command 'setup': discontinued implicit version with ML reference.
  2122 
  2123 * Instantiation target allows for simultaneous specification of class
  2124 instance operations together with an instantiation proof.
  2125 Type-checking phase allows to refer to class operations uniformly.
  2126 See src/HOL/Complex/Complex.thy for an Isar example and
  2127 src/HOL/Library/Eval.thy for an ML example.
  2128 
  2129 * Indexing of literal facts: be more serious about including only
  2130 facts from the visible specification/proof context, but not the
  2131 background context (locale etc.).  Affects `prop` notation and method
  2132 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2133 situations.
  2134 
  2135 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2136 "(open)" option, which used to expose internal bound variables to the
  2137 proof text.
  2138 
  2139 * Isar statements: removed obsolete case "rule_context".
  2140 INCOMPATIBILITY, better use explicit fixes/assumes.
  2141 
  2142 * Locale proofs: default proof step now includes 'unfold_locales';
  2143 hence 'proof' without argument may be used to unfold locale
  2144 predicates.
  2145 
  2146 
  2147 *** Document preparation ***
  2148 
  2149 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2150 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2151 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2152 spot); renamed link color from "darkblue" to "linkcolor" (default
  2153 value unchanged, can be redefined via \definecolor); no longer sets
  2154 "a4paper" option (unnecessary or even intrusive).
  2155 
  2156 * Antiquotation @{lemma A method} proves proposition A by the given
  2157 method (either a method name or a method name plus (optional) method
  2158 arguments in parentheses) and prints A just like @{prop A}.
  2159 
  2160 
  2161 *** HOL ***
  2162 
  2163 * New primrec package.  Specification syntax conforms in style to
  2164 definition/function/....  No separate induction rule is provided.  The
  2165 "primrec" command distinguishes old-style and new-style specifications
  2166 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2167 When adjusting theories, beware: constants stemming from new-style
  2168 primrec specifications have authentic syntax.
  2169 
  2170 * Metis prover is now an order of magnitude faster, and also works
  2171 with multithreading.
  2172 
  2173 * Metis: the maximum number of clauses that can be produced from a
  2174 theorem is now given by the attribute max_clauses.  Theorems that
  2175 exceed this number are ignored, with a warning printed.
  2176 
  2177 * Sledgehammer no longer produces structured proofs by default. To
  2178 enable, declare [[sledgehammer_full = true]].  Attributes
  2179 reconstruction_modulus, reconstruction_sorts renamed
  2180 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2181 
  2182 * Method "induct_scheme" derives user-specified induction rules
  2183 from well-founded induction and completeness of patterns. This factors
  2184 out some operations that are done internally by the function package
  2185 and makes them available separately.  See
  2186 src/HOL/ex/Induction_Scheme.thy for examples.
  2187 
  2188 * More flexible generation of measure functions for termination
  2189 proofs: Measure functions can be declared by proving a rule of the
  2190 form "is_measure f" and giving it the [measure_function] attribute.
  2191 The "is_measure" predicate is logically meaningless (always true), and
  2192 just guides the heuristic.  To find suitable measure functions, the
  2193 termination prover sets up the goal "is_measure ?f" of the appropriate
  2194 type and generates all solutions by prolog-style backwards proof using
  2195 the declared rules.
  2196 
  2197 This setup also deals with rules like 
  2198 
  2199   "is_measure f ==> is_measure (list_size f)"
  2200 
  2201 which accommodates nested datatypes that recurse through lists.
  2202 Similar rules are predeclared for products and option types.
  2203 
  2204 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2205 
  2206   INCOMPATIBILITIES:
  2207 
  2208   - Definitions of overloaded constants on sets have to be replaced by
  2209     definitions on => and bool.
  2210 
  2211   - Some definitions of overloaded operators on sets can now be proved
  2212     using the definitions of the operators on => and bool.  Therefore,
  2213     the following theorems have been renamed:
  2214 
  2215       subset_def   -> subset_eq
  2216       psubset_def  -> psubset_eq
  2217       set_diff_def -> set_diff_eq
  2218       Compl_def    -> Compl_eq
  2219       Sup_set_def  -> Sup_set_eq
  2220       Inf_set_def  -> Inf_set_eq
  2221       sup_set_def  -> sup_set_eq
  2222       inf_set_def  -> inf_set_eq
  2223 
  2224   - Due to the incompleteness of the HO unification algorithm, some
  2225     rules such as subst may require manual instantiation, if some of
  2226     the unknowns in the rule is a set.
  2227 
  2228   - Higher order unification and forward proofs:
  2229     The proof pattern
  2230 
  2231       have "P (S::'a set)" <...>
  2232       then have "EX S. P S" ..
  2233 
  2234     no longer works (due to the incompleteness of the HO unification
  2235     algorithm) and must be replaced by the pattern
  2236 
  2237       have "EX S. P S"
  2238       proof
  2239         show "P S" <...>
  2240       qed
  2241 
  2242   - Calculational reasoning with subst (or similar rules):
  2243     The proof pattern
  2244 
  2245       have "P (S::'a set)" <...>
  2246       also have "S = T" <...>
  2247       finally have "P T" .
  2248 
  2249     no longer works (for similar reasons as the previous example) and
  2250     must be replaced by something like
  2251 
  2252       have "P (S::'a set)" <...>
  2253       moreover have "S = T" <...>
  2254       ultimately have "P T" by simp
  2255 
  2256   - Tactics or packages written in ML code:
  2257     Code performing pattern matching on types via
  2258 
  2259       Type ("set", [T]) => ...
  2260 
  2261     must be rewritten. Moreover, functions like strip_type or
  2262     binder_types no longer return the right value when applied to a
  2263     type of the form
  2264 
  2265       T1 => ... => Tn => U => bool
  2266 
  2267     rather than
  2268 
  2269       T1 => ... => Tn => U set
  2270 
  2271 * Merged theories Wellfounded_Recursion, Accessible_Part and
  2272 Wellfounded_Relations to theory Wellfounded.
  2273 
  2274 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  2275 
  2276 * Class finite no longer treats UNIV as class parameter.  Use class
  2277 enum from theory Library/Enum instead to achieve a similar effect.
  2278 INCOMPATIBILITY.
  2279 
  2280 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  2281 and "Cons".  INCOMPATIBILITY.
  2282 
  2283 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  2284 Potential INCOMPATIBILITY.
  2285 
  2286 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  2287 injective_fst_snd removed, use split_eta and prod_eqI instead.
  2288 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  2289 
  2290 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  2291 the same name in theory Orderings:
  2292 
  2293   less_trans
  2294   less_linear
  2295   le_imp_less_or_eq
  2296   le_less_trans
  2297   less_le_trans
  2298   less_not_sym
  2299   less_asym
  2300 
  2301 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  2302 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  2303 and different variable names.
  2304 
  2305 * Library/Option_ord.thy: Canonical order on option type.
  2306 
  2307 * Library/RBT.thy: Red-black trees, an efficient implementation of
  2308 finite maps.
  2309 
  2310 * Library/Countable.thy: Type class for countable types.
  2311 
  2312 * Theory Int: The representation of numerals has changed.  The infix
  2313 operator BIT and the bit datatype with constructors B0 and B1 have
  2314 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  2315 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  2316 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  2317 accordingly.
  2318 
  2319 * Theory Nat: definition of <= and < on natural numbers no longer
  2320 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  2321 le_def and less_def have disappeared.  Consider lemmas not_less
  2322 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  2323 
  2324 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  2325 (whose purpose mainly is for various fold_set functionals) have been
  2326 abandoned in favor of the existing algebraic classes
  2327 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  2328 lower_semilattice (resp. upper_semilattice) and linorder.
  2329 INCOMPATIBILITY.
  2330 
  2331 * Theory Transitive_Closure: induct and cases rules now declare proper
  2332 case_names ("base" and "step").  INCOMPATIBILITY.
  2333 
  2334 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  2335 lattices.  The form set-specific version is available as
  2336 Inductive.lfp_ordinal_induct_set.
  2337 
  2338 * Renamed theorems "power.simps" to "power_int.simps".
  2339 INCOMPATIBILITY.
  2340 
  2341 * Class semiring_div provides basic abstract properties of semirings
  2342 with division and modulo operations.  Subsumes former class dvd_mod.
  2343 
  2344 * Merged theories IntDef, Numeral and IntArith into unified theory
  2345 Int.  INCOMPATIBILITY.
  2346 
  2347 * Theory Library/Code_Index: type "index" now represents natural
  2348 numbers rather than integers.  INCOMPATIBILITY.
  2349 
  2350 * New class "uminus" with operation "uminus" (split of from class
  2351 "minus" which now only has operation "minus", binary).
  2352 INCOMPATIBILITY.
  2353 
  2354 * Constants "card", "internal_split", "option_map" now with authentic
  2355 syntax.  INCOMPATIBILITY.
  2356 
  2357 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  2358 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  2359 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  2360 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  2361 Sup_set_def, le_def, less_def, option_map_def now with object
  2362 equality.  INCOMPATIBILITY.
  2363 
  2364 * Records. Removed K_record, and replaced it by pure lambda term
  2365 %x. c. The simplifier setup is now more robust against eta expansion.
  2366 INCOMPATIBILITY: in cases explicitly referring to K_record.
  2367 
  2368 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  2369 
  2370 * Library/ListVector: new theory of arithmetic vector operations.
  2371 
  2372 * Library/Order_Relation: new theory of various orderings as sets of
  2373 pairs.  Defines preorders, partial orders, linear orders and
  2374 well-orders on sets and on types.
  2375 
  2376 
  2377 *** ZF ***
  2378 
  2379 * Renamed some theories to allow to loading both ZF and HOL in the
  2380 same session:
  2381 
  2382   Datatype  -> Datatype_ZF
  2383   Inductive -> Inductive_ZF
  2384   Int       -> Int_ZF
  2385   IntDiv    -> IntDiv_ZF
  2386   Nat       -> Nat_ZF
  2387   List      -> List_ZF
  2388   Main      -> Main_ZF
  2389 
  2390 INCOMPATIBILITY: ZF theories that import individual theories below
  2391 Main might need to be adapted.  Regular theory Main is still
  2392 available, as trivial extension of Main_ZF.
  2393 
  2394 
  2395 *** ML ***
  2396 
  2397 * ML within Isar: antiquotation @{const name} or @{const
  2398 name(typargs)} produces statically-checked Const term.
  2399 
  2400 * Functor NamedThmsFun: data is available to the user as dynamic fact
  2401 (of the same name).  Removed obsolete print command.
  2402 
  2403 * Removed obsolete "use_legacy_bindings" function.
  2404 
  2405 * The ``print mode'' is now a thread-local value derived from a global
  2406 template (the former print_mode reference), thus access becomes
  2407 non-critical.  The global print_mode reference is for session
  2408 management only; user-code should use print_mode_value,
  2409 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  2410 
  2411 * Functions system/system_out provide a robust way to invoke external
  2412 shell commands, with propagation of interrupts (requires Poly/ML
  2413 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  2414 
  2415 
  2416 *** System ***
  2417 
  2418 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  2419 in accordance with Proof General 3.7, which prefers GNU emacs.
  2420 
  2421 * isatool tty runs Isabelle process with plain tty interaction;
  2422 optional line editor may be specified via ISABELLE_LINE_EDITOR
  2423 setting, the default settings attempt to locate "ledit" and "rlwrap".
  2424 
  2425 * isatool browser now works with Cygwin as well, using general
  2426 "javapath" function defined in Isabelle process environment.
  2427 
  2428 * YXML notation provides a simple and efficient alternative to
  2429 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  2430 isatool yxml as described in the Isabelle system manual.
  2431 
  2432 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  2433 provides general wrapper for managing an Isabelle process in a robust
  2434 fashion, with ``cooked'' output from stdin/stderr.
  2435 
  2436 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  2437 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  2438 
  2439 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  2440 way of changing the user's settings is via
  2441 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  2442 script.
  2443 
  2444 * Multithreading.max_threads := 0 refers to the number of actual CPU
  2445 cores of the underlying machine, which is a good starting point for
  2446 optimal performance tuning.  The corresponding usedir option -M allows
  2447 "max" as an alias for "0".  WARNING: does not work on certain versions
  2448 of Mac OS (with Poly/ML 5.1).
  2449 
  2450 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  2451 adverse effect of Isabelle flooding interactive front-ends (notably
  2452 ProofGeneral / XEmacs).
  2453 
  2454 
  2455 
  2456 New in Isabelle2007 (November 2007)
  2457 -----------------------------------
  2458 
  2459 *** General ***
  2460 
  2461 * More uniform information about legacy features, notably a
  2462 warning/error of "Legacy feature: ...", depending on the state of the
  2463 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  2464 legacy features will disappear eventually.
  2465 
  2466 * Theory syntax: the header format ``theory A = B + C:'' has been
  2467 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  2468 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  2469 
  2470 * Theory syntax: the old non-Isar theory file format has been
  2471 discontinued altogether.  Note that ML proof scripts may still be used
  2472 with Isar theories; migration is usually quite simple with the ML
  2473 function use_legacy_bindings.  INCOMPATIBILITY.
  2474 
  2475 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  2476 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  2477 quotes.
  2478 
  2479 * Theory loader: be more serious about observing the static theory
  2480 header specifications (including optional directories), but not the
  2481 accidental file locations of previously successful loads.  The strict
  2482 update policy of former update_thy is now already performed by
  2483 use_thy, so the former has been removed; use_thys updates several
  2484 theories simultaneously, just as 'imports' within a theory header
  2485 specification, but without merging the results.  Potential
  2486 INCOMPATIBILITY: may need to refine theory headers and commands
  2487 ROOT.ML which depend on load order.
  2488 
  2489 * Theory loader: optional support for content-based file
  2490 identification, instead of the traditional scheme of full physical
  2491 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  2492 (cf. the system manual).  The new scheme allows to work with
  2493 non-finished theories in persistent session images, such that source
  2494 files may be moved later on without requiring reloads.
  2495 
  2496 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2497 file (with the same base name as the theory) are considered a legacy
  2498 feature, which will disappear eventually. Even now, the theory loader
  2499 no longer maintains dependencies on such files.
  2500 
  2501 * Syntax: the scope for resolving ambiguities via type-inference is
  2502 now limited to individual terms, instead of whole simultaneous
  2503 specifications as before. This greatly reduces the complexity of the
  2504 syntax module and improves flexibility by separating parsing and
  2505 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  2506 'fixes' etc.) are required in rare situations.
  2507 
  2508 * Syntax: constants introduced by new-style packages ('definition',
  2509 'abbreviation' etc.) are passed through the syntax module in
  2510 ``authentic mode''. This means that associated mixfix annotations
  2511 really stick to such constants, independently of potential name space
  2512 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  2513 trees are represented slightly differently, may need to adapt syntax
  2514 translations accordingly. Use CONST marker in 'translations' and
  2515 @{const_syntax} antiquotation in 'parse_translation' etc.
  2516 
  2517 * Legacy goal package: reduced interface to the bare minimum required
  2518 to keep existing proof scripts running.  Most other user-level
  2519 functions are now part of the OldGoals structure, which is *not* open
  2520 by default (consider isatool expandshort before open OldGoals).
  2521 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  2522 these tend to cause confusion about the actual goal (!) context being
  2523 used here, which is not necessarily the same as the_context().
  2524 
  2525 * Command 'find_theorems': supports "*" wild-card in "name:"
  2526 criterion; "with_dups" option.  Certain ProofGeneral versions might
  2527 support a specific search form (see ProofGeneral/CHANGES).
  2528 
  2529 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  2530 by default, which means that "prems" (and also "fixed variables") are
  2531 suppressed from proof state output.  Note that the ProofGeneral
  2532 settings mechanism allows to change and save options persistently, but
  2533 older versions of Isabelle will fail to start up if a negative prems
  2534 limit is imposed.
  2535 
  2536 * Local theory targets may be specified by non-nested blocks of
  2537 ``context/locale/class ... begin'' followed by ``end''.  The body may
  2538 contain definitions, theorems etc., including any derived mechanism
  2539 that has been implemented on top of these primitives.  This concept
  2540 generalizes the existing ``theorem (in ...)'' towards more versatility
  2541 and scalability.
  2542 
  2543 * Proof General interface: proper undo of final 'end' command;
  2544 discontinued Isabelle/classic mode (ML proof scripts).
  2545 
  2546 
  2547 *** Document preparation ***
  2548 
  2549 * Added antiquotation @{theory name} which prints the given name,
  2550 after checking that it refers to a valid ancestor theory in the
  2551 current context.
  2552 
  2553 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  2554 check the given source text as ML type/structure, printing verbatim.
  2555 
  2556 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  2557 "c args == rhs" given in the current context.  (Any number of
  2558 arguments may be given on the LHS.)
  2559 
  2560 
  2561 *** Pure ***
  2562 
  2563 * The 'class' package offers a combination of axclass and locale to
  2564 achieve Haskell-like type classes in Isabelle.  Definitions and
  2565 theorems within a class context produce both relative results (with
  2566 implicit parameters according to the locale context), and polymorphic
  2567 constants with qualified polymorphism (according to the class
  2568 context).  Within the body context of a 'class' target, a separate
  2569 syntax layer ("user space type system") takes care of converting
  2570 between global polymorphic consts and internal locale representation.
  2571 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  2572 "isatool doc classes" provides a tutorial.
  2573 
  2574 * Generic code generator framework allows to generate executable
  2575 code for ML and Haskell (including Isabelle classes).  A short usage
  2576 sketch:
  2577 
  2578     internal compilation:
  2579         export_code <list of constants (term syntax)> in SML
  2580     writing SML code to a file:
  2581         export_code <list of constants (term syntax)> in SML <filename>
  2582     writing OCaml code to a file:
  2583         export_code <list of constants (term syntax)> in OCaml <filename>
  2584     writing Haskell code to a bunch of files:
  2585         export_code <list of constants (term syntax)> in Haskell <filename>
  2586 
  2587     evaluating closed propositions to True/False using code generation:
  2588         method ``eval''
  2589 
  2590 Reasonable default setup of framework in HOL.
  2591 
  2592 Theorem attributs for selecting and transforming function equations theorems:
  2593 
  2594     [code fun]:        select a theorem as function equation for a specific constant
  2595     [code fun del]:    deselect a theorem as function equation for a specific constant
  2596     [code inline]:     select an equation theorem for unfolding (inlining) in place
  2597     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  2598 
  2599 User-defined serializations (target in {SML, OCaml, Haskell}):
  2600 
  2601     code_const <and-list of constants (term syntax)>
  2602       {(target) <and-list of const target syntax>}+
  2603 
  2604     code_type <and-list of type constructors>
  2605       {(target) <and-list of type target syntax>}+
  2606 
  2607     code_instance <and-list of instances>
  2608       {(target)}+
  2609         where instance ::= <type constructor> :: <class>
  2610 
  2611     code_class <and_list of classes>
  2612       {(target) <and-list of class target syntax>}+
  2613         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  2614 
  2615 code_instance and code_class only are effective to target Haskell.
  2616 
  2617 For example usage see src/HOL/ex/Codegenerator.thy and
  2618 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  2619 generation from Isabelle/HOL theories is available via "isatool doc
  2620 codegen".
  2621 
  2622 * Code generator: consts in 'consts_code' Isar commands are now
  2623 referred to by usual term syntax (including optional type
  2624 annotations).
  2625 
  2626 * Command 'no_translations' removes translation rules from theory
  2627 syntax.
  2628 
  2629 * Overloaded definitions are now actually checked for acyclic
  2630 dependencies.  The overloading scheme is slightly more general than
  2631 that of Haskell98, although Isabelle does not demand an exact
  2632 correspondence to type class and instance declarations.
  2633 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  2634 exotic versions of overloading -- at the discretion of the user!
  2635 
  2636 Polymorphic constants are represented via type arguments, i.e. the
  2637 instantiation that matches an instance against the most general
  2638 declaration given in the signature.  For example, with the declaration
  2639 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  2640 as c(nat).  Overloading is essentially simultaneous structural
  2641 recursion over such type arguments.  Incomplete specification patterns
  2642 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  2643 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  2644 Command 'print_theory' outputs the normalized system of recursive
  2645 equations, see section "definitions".
  2646 
  2647 * Configuration options are maintained within the theory or proof
  2648 context (with name and type bool/int/string), providing a very simple
  2649 interface to a poor-man's version of general context data.  Tools may
  2650 declare options in ML (e.g. using Attrib.config_int) and then refer to
  2651 these values using Config.get etc.  Users may change options via an
  2652 associated attribute of the same name.  This form of context
  2653 declaration works particularly well with commands 'declare' or
  2654 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  2655 very easy to avoid global references, which would not observe Isar
  2656 toplevel undo/redo and fail to work with multithreading.
  2657 
  2658 Various global ML references of Pure and HOL have been turned into
  2659 configuration options:
  2660 
  2661   Unify.search_bound		unify_search_bound
  2662   Unify.trace_bound		unify_trace_bound
  2663   Unify.trace_simp		unify_trace_simp
  2664   Unify.trace_types		unify_trace_types
  2665   Simplifier.simp_depth_limit	simp_depth_limit
  2666   Blast.depth_limit		blast_depth_limit
  2667   DatatypeProp.dtK		datatype_distinctness_limit
  2668   fast_arith_neq_limit  	fast_arith_neq_limit
  2669   fast_arith_split_limit	fast_arith_split_limit
  2670 
  2671 * Named collections of theorems may be easily installed as context
  2672 data using the functor NamedThmsFun (see also
  2673 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  2674 attributes; there is also a toplevel print command.  This facility is
  2675 just a common case of general context data, which is the preferred way
  2676 for anything more complex than just a list of facts in canonical
  2677 order.
  2678 
  2679 * Isar: command 'declaration' augments a local theory by generic
  2680 declaration functions written in ML.  This enables arbitrary content
  2681 being added to the context, depending on a morphism that tells the
  2682 difference of the original declaration context wrt. the application
  2683 context encountered later on.
  2684 
  2685 * Isar: proper interfaces for simplification procedures.  Command
  2686 'simproc_setup' declares named simprocs (with match patterns, and body
  2687 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  2688 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  2689 
  2690 * Isar: an extra pair of brackets around attribute declarations
  2691 abbreviates a theorem reference involving an internal dummy fact,
  2692 which will be ignored later --- only the effect of the attribute on
  2693 the background context will persist.  This form of in-place
  2694 declarations is particularly useful with commands like 'declare' and
  2695 'using', for example ``have A using [[simproc a]] by simp''.
  2696 
  2697 * Isar: method "assumption" (and implicit closing of subproofs) now
  2698 takes simple non-atomic goal assumptions into account: after applying
  2699 an assumption as a rule the resulting subgoals are solved by atomic
  2700 assumption steps.  This is particularly useful to finish 'obtain'
  2701 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  2702 without referring to the original premise "!!x. P x ==> thesis" in the
  2703 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  2704 more permissive.
  2705 
  2706 * Isar: implicit use of prems from the Isar proof context is
  2707 considered a legacy feature.  Common applications like ``have A .''
  2708 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  2709 referencing facts explicitly here improves readability and
  2710 maintainability of proof texts.
  2711 
  2712 * Isar: improper proof element 'guess' is like 'obtain', but derives
  2713 the obtained context from the course of reasoning!  For example:
  2714 
  2715   assume "EX x y. A x & B y"   -- "any previous fact"
  2716   then guess x and y by clarify
  2717 
  2718 This technique is potentially adventurous, depending on the facts and
  2719 proof tools being involved here.
  2720 
  2721 * Isar: known facts from the proof context may be specified as literal
  2722 propositions, using ASCII back-quote syntax.  This works wherever
  2723 named facts used to be allowed so far, in proof commands, proof
  2724 methods, attributes etc.  Literal facts are retrieved from the context
  2725 according to unification of type and term parameters.  For example,
  2726 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  2727 theorems in the current context, then these are valid literal facts:
  2728 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  2729 
  2730 There is also a proof method "fact" which does the same composition
  2731 for explicit goal states, e.g. the following proof texts coincide with
  2732 certain special cases of literal facts:
  2733 
  2734   have "A" by fact                 ==  note `A`
  2735   have "A ==> B" by fact           ==  note `A ==> B`
  2736   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  2737   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  2738 
  2739 * Isar: ":" (colon) is no longer a symbolic identifier character in
  2740 outer syntax.  Thus symbolic identifiers may be used without
  2741 additional white space in declarations like this: ``assume *: A''.
  2742 
  2743 * Isar: 'print_facts' prints all local facts of the current context,
  2744 both named and unnamed ones.
  2745 
  2746 * Isar: 'def' now admits simultaneous definitions, e.g.:
  2747 
  2748   def x == "t" and y == "u"
  2749 
  2750 * Isar: added command 'unfolding', which is structurally similar to
  2751 'using', but affects both the goal state and facts by unfolding given
  2752 rewrite rules.  Thus many occurrences of the 'unfold' method or
  2753 'unfolded' attribute may be replaced by first-class proof text.
  2754 
  2755 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  2756 and command 'unfolding' now all support object-level equalities
  2757 (potentially conditional).  The underlying notion of rewrite rule is
  2758 analogous to the 'rule_format' attribute, but *not* that of the
  2759 Simplifier (which is usually more generous).
  2760 
  2761 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  2762 premises of a theorem by n. Useful in conjunction with drule.
  2763 
  2764 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  2765 method expression within a sandbox consisting of the first N
  2766 sub-goals, which need to exist.  For example, ``simp_all [3]''
  2767 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  2768 simplifies all new goals that emerge from applying rule foo to the
  2769 originally first one.
  2770 
  2771 * Isar: schematic goals are no longer restricted to higher-order
  2772 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  2773 expected.
  2774 
  2775 * Isar: the conclusion of a long theorem statement is now either
  2776 'shows' (a simultaneous conjunction, as before), or 'obtains'
  2777 (essentially a disjunction of cases with local parameters and
  2778 assumptions).  The latter allows to express general elimination rules
  2779 adequately; in this notation common elimination rules look like this:
  2780 
  2781   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  2782     assumes "EX x. P x"
  2783     obtains x where "P x"
  2784 
  2785   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  2786     assumes "A & B"
  2787     obtains A and B
  2788 
  2789   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  2790     assumes "A | B"
  2791     obtains
  2792       A
  2793     | B
  2794 
  2795 The subsequent classical rules even refer to the formal "thesis"
  2796 explicitly:
  2797 
  2798   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  2799     obtains "~ thesis"
  2800 
  2801   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  2802     obtains "thesis ==> something"
  2803 
  2804 The actual proof of an 'obtains' statement is analogous to that of the
  2805 Isar proof element 'obtain', only that there may be several cases.
  2806 Optional case names may be specified in parentheses; these will be
  2807 available both in the present proof and as annotations in the
  2808 resulting rule, for later use with the 'cases' method (cf. attribute
  2809 case_names).
  2810 
  2811 * Isar: the assumptions of a long theorem statement are available as
  2812 "assms" fact in the proof context.  This is more appropriate than the
  2813 (historical) "prems", which refers to all assumptions of the current
  2814 context, including those from the target locale, proof body etc.
  2815 
  2816 * Isar: 'print_statement' prints theorems from the current theory or
  2817 proof context in long statement form, according to the syntax of a
  2818 top-level lemma.
  2819 
  2820 * Isar: 'obtain' takes an optional case name for the local context
  2821 introduction rule (default "that").
  2822 
  2823 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  2824 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  2825 to occur.
  2826 
  2827 * Pure: syntax "CONST name" produces a fully internalized constant
  2828 according to the current context.  This is particularly useful for
  2829 syntax translations that should refer to internal constant
  2830 representations independently of name spaces.
  2831 
  2832 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  2833 instead of "FOO ". This allows multiple binder declarations to coexist
  2834 in the same context.  INCOMPATIBILITY.
  2835 
  2836 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  2837 primitive that also works in a locale context (both for constants and
  2838 fixed variables). Type declaration and internal syntactic representation
  2839 of given constants retrieved from the context. Likewise, the
  2840 'no_notation' command allows to remove given syntax annotations from the
  2841 current context.
  2842 
  2843 * Isar/locales: new derived specification elements 'axiomatization',
  2844 'definition', 'abbreviation', which support type-inference, admit
  2845 object-level specifications (equality, equivalence).  See also the
  2846 isar-ref manual.  Examples:
  2847 
  2848   axiomatization
  2849     eq  (infix "===" 50) where
  2850     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  2851 
  2852   definition "f x y = x + y + 1"
  2853   definition g where "g x = f x x"
  2854 
  2855   abbreviation
  2856     neq  (infix "=!=" 50) where
  2857     "x =!= y == ~ (x === y)"
  2858 
  2859 These specifications may be also used in a locale context.  Then the
  2860 constants being introduced depend on certain fixed parameters, and the
  2861 constant name is qualified by the locale base name.  An internal
  2862 abbreviation takes care for convenient input and output, making the
  2863 parameters implicit and using the original short name.  See also
  2864 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  2865 entities from a monomorphic theory.
  2866 
  2867 Presently, abbreviations are only available 'in' a target locale, but
  2868 not inherited by general import expressions.  Also note that
  2869 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  2870 'translations' in common applications.  The "no_abbrevs" print mode
  2871 prevents folding of abbreviations in term output.
  2872 
  2873 Concrete syntax is attached to specified constants in internal form,
  2874 independently of name spaces.  The parse tree representation is
  2875 slightly different -- use 'notation' instead of raw 'syntax', and
  2876 'translations' with explicit "CONST" markup to accommodate this.
  2877 
  2878 * Pure/Isar: unified syntax for new-style specification mechanisms
  2879 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  2880 full type inference and dummy patterns ("_").  For example:
  2881 
  2882   definition "K x _ = x"
  2883 
  2884   inductive conj for A B
  2885   where "A ==> B ==> conj A B"
  2886 
  2887 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  2888 the current context.  Print mode "no_abbrevs" prevents inversion of
  2889 abbreviations on output.
  2890 
  2891 * Isar/locales: improved parameter handling: use of locales "var" and
  2892 "struct" no longer necessary; - parameter renamings are no longer
  2893 required to be injective.  For example, this allows to define
  2894 endomorphisms as locale endom = homom mult mult h.
  2895 
  2896 * Isar/locales: changed the way locales with predicates are defined.
  2897 Instead of accumulating the specification, the imported expression is
  2898 now an interpretation.  INCOMPATIBILITY: different normal form of
  2899 locale expressions.  In particular, in interpretations of locales with
  2900 predicates, goals repesenting already interpreted fragments are not
  2901 removed automatically.  Use methods `intro_locales' and
  2902 `unfold_locales'; see below.
  2903 
  2904 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  2905 provide backward reasoning on locales predicates.  The methods are
  2906 aware of interpretations and discharge corresponding goals.
  2907 `intro_locales' is less aggressive then `unfold_locales' and does not
  2908 unfold predicates to assumptions.
  2909 
  2910 * Isar/locales: the order in which locale fragments are accumulated
  2911 has changed.  This enables to override declarations from fragments due
  2912 to interpretations -- for example, unwanted simp rules.
  2913 
  2914 * Isar/locales: interpretation in theories and proof contexts has been
  2915 extended.  One may now specify (and prove) equations, which are
  2916 unfolded in interpreted theorems.  This is useful for replacing
  2917 defined concepts (constants depending on locale parameters) by
  2918 concepts already existing in the target context.  Example:
  2919 
  2920   interpretation partial_order ["op <= :: [int, int] => bool"]
  2921     where "partial_order.less (op <=) (x::int) y = (x < y)"
  2922 
  2923 Typically, the constant `partial_order.less' is created by a
  2924 definition specification element in the context of locale
  2925 partial_order.
  2926 
  2927 * Method "induct": improved internal context management to support
  2928 local fixes and defines on-the-fly. Thus explicit meta-level
  2929 connectives !!  and ==> are rarely required anymore in inductive goals
  2930 (using object-logic connectives for this purpose has been long
  2931 obsolete anyway). Common proof patterns are explained in
  2932 src/HOL/Induct/Common_Patterns.thy, see also
  2933 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  2934 examples.
  2935 
  2936 * Method "induct": improved handling of simultaneous goals. Instead of
  2937 introducing object-level conjunction, the statement is now split into
  2938 several conclusions, while the corresponding symbolic cases are nested
  2939 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  2940 see src/HOL/Induct/Common_Patterns.thy, for example.
  2941 
  2942 * Method "induct": mutual induction rules are now specified as a list
  2943 of rule sharing the same induction cases. HOL packages usually provide
  2944 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  2945 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  2946 mutual induction rules differently, i.e. like this:
  2947 
  2948   (induct rule: foo_bar.inducts)
  2949   (induct set: foo bar)
  2950   (induct pred: foo bar)
  2951   (induct type: foo bar)
  2952 
  2953 The ML function ProjectRule.projections turns old-style rules into the
  2954 new format.
  2955 
  2956 * Method "coinduct": dual of induction, see
  2957 src/HOL/Library/Coinductive_List.thy for various examples.
  2958 
  2959 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  2960 considered a legacy feature.
  2961 
  2962 * Attribute "symmetric" produces result with standardized schematic
  2963 variables (index 0).  Potential INCOMPATIBILITY.
  2964 
  2965 * Simplifier: by default the simplifier trace only shows top level
  2966 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  2967 default. Thus there is less danger of being flooded by the trace. The
  2968 trace indicates where parts have been suppressed.
  2969   
  2970 * Provers/classical: removed obsolete classical version of elim_format
  2971 attribute; classical elim/dest rules are now treated uniformly when
  2972 manipulating the claset.
  2973 
  2974 * Provers/classical: stricter checks to ensure that supplied intro,
  2975 dest and elim rules are well-formed; dest and elim rules must have at
  2976 least one premise.
  2977 
  2978 * Provers/classical: attributes dest/elim/intro take an optional
  2979 weight argument for the rule (just as the Pure versions).  Weights are
  2980 ignored by automated tools, but determine the search order of single
  2981 rule steps.
  2982 
  2983 * Syntax: input syntax now supports dummy variable binding "%_. b",
  2984 where the body does not mention the bound variable.  Note that dummy
  2985 patterns implicitly depend on their context of bounds, which makes
  2986 "{_. _}" match any set comprehension as expected.  Potential
  2987 INCOMPATIBILITY -- parse translations need to cope with syntactic
  2988 constant "_idtdummy" in the binding position.
  2989 
  2990 * Syntax: removed obsolete syntactic constant "_K" and its associated
  2991 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  2992 for example "A -> B" => "Pi A (%_. B)".
  2993 
  2994 * Pure: 'class_deps' command visualizes the subclass relation, using
  2995 the graph browser tool.
  2996 
  2997 * Pure: 'print_theory' now suppresses certain internal declarations by
  2998 default; use '!' option for full details.
  2999 
  3000 
  3001 *** HOL ***
  3002 
  3003 * Method "metis" proves goals by applying the Metis general-purpose
  3004 resolution prover (see also http://gilith.com/software/metis/).
  3005 Examples are in the directory MetisExamples.  WARNING: the
  3006 Isabelle/HOL-Metis integration does not yet work properly with
  3007 multi-threading.
  3008   
  3009 * Command 'sledgehammer' invokes external automatic theorem provers as
  3010 background processes.  It generates calls to the "metis" method if
  3011 successful. These can be pasted into the proof.  Users do not have to
  3012 wait for the automatic provers to return.  WARNING: does not really
  3013 work with multi-threading.
  3014 
  3015 * New "auto_quickcheck" feature tests outermost goal statements for
  3016 potential counter-examples.  Controlled by ML references
  3017 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3018 5000 milliseconds).  Fails silently if statements is outside of
  3019 executable fragment, or any other codgenerator problem occurs.
  3020 
  3021 * New constant "undefined" with axiom "undefined x = undefined".
  3022 
  3023 * Added class "HOL.eq", allowing for code generation with polymorphic
  3024 equality.
  3025 
  3026 * Some renaming of class constants due to canonical name prefixing in
  3027 the new 'class' package:
  3028 
  3029     HOL.abs ~> HOL.abs_class.abs
  3030     HOL.divide ~> HOL.divide_class.divide
  3031     0 ~> HOL.zero_class.zero
  3032     1 ~> HOL.one_class.one
  3033     op + ~> HOL.plus_class.plus
  3034     op - ~> HOL.minus_class.minus
  3035     uminus ~> HOL.minus_class.uminus
  3036     op * ~> HOL.times_class.times
  3037     op < ~> HOL.ord_class.less
  3038     op <= > HOL.ord_class.less_eq
  3039     Nat.power ~> Power.power_class.power
  3040     Nat.size ~> Nat.size_class.size
  3041     Numeral.number_of ~> Numeral.number_class.number_of
  3042     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3043     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3044     Orderings.min ~> Orderings.ord_class.min
  3045     Orderings.max ~> Orderings.ord_class.max
  3046     Divides.op div ~> Divides.div_class.div
  3047     Divides.op mod ~> Divides.div_class.mod
  3048     Divides.op dvd ~> Divides.div_class.dvd
  3049 
  3050 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3051 
  3052 a) User-defined constants using any of the names "plus", "minus",
  3053 "times", "less" or "less_eq". The standard syntax translations for
  3054 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3055 names.
  3056 
  3057 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3058 INCOMPATIBILITY: use more specific names.
  3059 
  3060 c) Permutative equations (e.g. "a + b = b + a")
  3061 Since the change of names also changes the order of terms, permutative
  3062 rewrite rules may get applied in a different order. Experience shows
  3063 that this is rarely the case (only two adaptions in the whole Isabelle
  3064 distribution).  INCOMPATIBILITY: rewrite proofs
  3065 
  3066 d) ML code directly refering to constant names
  3067 This in general only affects hand-written proof tactics, simprocs and
  3068 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3069 Consider using @{const_name} antiquotation.
  3070 
  3071 * New class "default" with associated constant "default".
  3072 
  3073 * Function "sgn" is now overloaded and available on int, real, complex
  3074 (and other numeric types), using class "sgn".  Two possible defs of
  3075 sgn are given as equational assumptions in the classes sgn_if and
  3076 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3077 INCOMPATIBILITY.
  3078 
  3079 * Locale "partial_order" now unified with class "order" (cf. theory
  3080 Orderings), added parameter "less".  INCOMPATIBILITY.
  3081 
  3082 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3083 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3084 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3085 
  3086 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3087 changed order of proof goals in instance proofs.
  3088 
  3089 * The transitivity reasoner for partial and linear orders is set up
  3090 for classes "order" and "linorder".  Instances of the reasoner are available
  3091 in all contexts importing or interpreting the corresponding locales.
  3092 Method "order" invokes the reasoner separately; the reasoner
  3093 is also integrated with the Simplifier as a solver.  Diagnostic
  3094 command 'print_orders' shows the available instances of the reasoner
  3095 in the current context.
  3096 
  3097 * Localized monotonicity predicate in theory "Orderings"; integrated
  3098 lemmas max_of_mono and min_of_mono with this predicate.
  3099 INCOMPATIBILITY.
  3100 
  3101 * Formulation of theorem "dense" changed slightly due to integration
  3102 with new class dense_linear_order.
  3103 
  3104 * Uniform lattice theory development in HOL.
  3105 
  3106     constants "meet" and "join" now named "inf" and "sup"
  3107     constant "Meet" now named "Inf"
  3108 
  3109     classes "meet_semilorder" and "join_semilorder" now named
  3110       "lower_semilattice" and "upper_semilattice"
  3111     class "lorder" now named "lattice"
  3112     class "comp_lat" now named "complete_lattice"
  3113 
  3114     Instantiation of lattice classes allows explicit definitions
  3115     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3116 
  3117   INCOMPATIBILITY.  Theorem renames:
  3118 
  3119     meet_left_le            ~> inf_le1
  3120     meet_right_le           ~> inf_le2
  3121     join_left_le            ~> sup_ge1
  3122     join_right_le           ~> sup_ge2
  3123     meet_join_le            ~> inf_sup_ord
  3124     le_meetI                ~> le_infI
  3125     join_leI                ~> le_supI
  3126     le_meet                 ~> le_inf_iff
  3127     le_join                 ~> ge_sup_conv
  3128     meet_idempotent         ~> inf_idem
  3129     join_idempotent         ~> sup_idem
  3130     meet_comm               ~> inf_commute
  3131     join_comm               ~> sup_commute
  3132     meet_leI1               ~> le_infI1
  3133     meet_leI2               ~> le_infI2
  3134     le_joinI1               ~> le_supI1
  3135     le_joinI2               ~> le_supI2
  3136     meet_assoc              ~> inf_assoc
  3137     join_assoc              ~> sup_assoc
  3138     meet_left_comm          ~> inf_left_commute
  3139     meet_left_idempotent    ~> inf_left_idem
  3140     join_left_comm          ~> sup_left_commute
  3141     join_left_idempotent    ~> sup_left_idem
  3142     meet_aci                ~> inf_aci
  3143     join_aci                ~> sup_aci
  3144     le_def_meet             ~> le_iff_inf
  3145     le_def_join             ~> le_iff_sup
  3146     join_absorp2            ~> sup_absorb2
  3147     join_absorp1            ~> sup_absorb1
  3148     meet_absorp1            ~> inf_absorb1
  3149     meet_absorp2            ~> inf_absorb2
  3150     meet_join_absorp        ~> inf_sup_absorb
  3151     join_meet_absorp        ~> sup_inf_absorb
  3152     distrib_join_le         ~> distrib_sup_le
  3153     distrib_meet_le         ~> distrib_inf_le
  3154 
  3155     add_meet_distrib_left   ~> add_inf_distrib_left
  3156     add_join_distrib_left   ~> add_sup_distrib_left
  3157     is_join_neg_meet        ~> is_join_neg_inf
  3158     is_meet_neg_join        ~> is_meet_neg_sup
  3159     add_meet_distrib_right  ~> add_inf_distrib_right
  3160     add_join_distrib_right  ~> add_sup_distrib_right
  3161     add_meet_join_distribs  ~> add_sup_inf_distribs
  3162     join_eq_neg_meet        ~> sup_eq_neg_inf
  3163     meet_eq_neg_join        ~> inf_eq_neg_sup
  3164     add_eq_meet_join        ~> add_eq_inf_sup
  3165     meet_0_imp_0            ~> inf_0_imp_0
  3166     join_0_imp_0            ~> sup_0_imp_0
  3167     meet_0_eq_0             ~> inf_0_eq_0
  3168     join_0_eq_0             ~> sup_0_eq_0
  3169     neg_meet_eq_join        ~> neg_inf_eq_sup
  3170     neg_join_eq_meet        ~> neg_sup_eq_inf
  3171     join_eq_if              ~> sup_eq_if
  3172 
  3173     mono_meet               ~> mono_inf
  3174     mono_join               ~> mono_sup
  3175     meet_bool_eq            ~> inf_bool_eq
  3176     join_bool_eq            ~> sup_bool_eq
  3177     meet_fun_eq             ~> inf_fun_eq
  3178     join_fun_eq             ~> sup_fun_eq
  3179     meet_set_eq             ~> inf_set_eq
  3180     join_set_eq             ~> sup_set_eq
  3181     meet1_iff               ~> inf1_iff
  3182     meet2_iff               ~> inf2_iff
  3183     meet1I                  ~> inf1I
  3184     meet2I                  ~> inf2I
  3185     meet1D1                 ~> inf1D1
  3186     meet2D1                 ~> inf2D1
  3187     meet1D2                 ~> inf1D2
  3188     meet2D2                 ~> inf2D2
  3189     meet1E                  ~> inf1E
  3190     meet2E                  ~> inf2E
  3191     join1_iff               ~> sup1_iff
  3192     join2_iff               ~> sup2_iff
  3193     join1I1                 ~> sup1I1
  3194     join2I1                 ~> sup2I1
  3195     join1I1                 ~> sup1I1
  3196     join2I2                 ~> sup1I2
  3197     join1CI                 ~> sup1CI
  3198     join2CI                 ~> sup2CI
  3199     join1E                  ~> sup1E
  3200     join2E                  ~> sup2E
  3201 
  3202     is_meet_Meet            ~> is_meet_Inf
  3203     Meet_bool_def           ~> Inf_bool_def
  3204     Meet_fun_def            ~> Inf_fun_def
  3205     Meet_greatest           ~> Inf_greatest
  3206     Meet_lower              ~> Inf_lower
  3207     Meet_set_def            ~> Inf_set_def
  3208 
  3209     Sup_def                 ~> Sup_Inf
  3210     Sup_bool_eq             ~> Sup_bool_def
  3211     Sup_fun_eq              ~> Sup_fun_def
  3212     Sup_set_eq              ~> Sup_set_def
  3213 
  3214     listsp_meetI            ~> listsp_infI
  3215     listsp_meet_eq          ~> listsp_inf_eq
  3216 
  3217     meet_min                ~> inf_min
  3218     join_max                ~> sup_max
  3219 
  3220 * Added syntactic class "size"; overloaded constant "size" now has
  3221 type "'a::size ==> bool"
  3222 
  3223 * Internal reorganisation of `size' of datatypes: size theorems
  3224 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3225 simplification rules by default!); theorems "prod.size" now named
  3226 "*.size".
  3227 
  3228 * Class "div" now inherits from class "times" rather than "type".
  3229 INCOMPATIBILITY.
  3230 
  3231 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  3232 Linorder etc.  have disappeared; operations defined in terms of
  3233 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  3234 
  3235 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  3236 
  3237 * HOL-Word: New extensive library and type for generic, fixed size
  3238 machine words, with arithemtic, bit-wise, shifting and rotating
  3239 operations, reflection into int, nat, and bool lists, automation for
  3240 linear arithmetic (by automatic reflection into nat or int), including
  3241 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  3242 arithmetic type classes, supporting automatic simplification of
  3243 numerals on all operations.
  3244 
  3245 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  3246 
  3247 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  3248 
  3249 * Code generator library theories:
  3250   - Code_Integer represents HOL integers by big integer literals in target
  3251     languages.
  3252   - Code_Char represents HOL characters by character literals in target
  3253     languages.
  3254   - Code_Char_chr like Code_Char, but also offers treatment of character
  3255     codes; includes Code_Integer.
  3256   - Executable_Set allows to generate code for finite sets using lists.
  3257   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  3258     denominator).
  3259   - Executable_Real implements a subset of real numbers, namly those
  3260     representable by rational numbers.
  3261   - Efficient_Nat implements natural numbers by integers, which in general will
  3262     result in higher efficency; pattern matching with 0/Suc is eliminated;
  3263     includes Code_Integer.
  3264   - Code_Index provides an additional datatype index which is mapped to
  3265     target-language built-in integers.
  3266   - Code_Message provides an additional datatype message_string which is isomorphic to
  3267     strings; messages are mapped to target-language strings.
  3268 
  3269 * New package for inductive predicates
  3270 
  3271   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  3272 
  3273     inductive
  3274       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3275       for z_1 :: U_1 and ... and z_n :: U_m
  3276     where
  3277       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3278     | ...
  3279 
  3280   with full support for type-inference, rather than
  3281 
  3282     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3283 
  3284     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3285     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3286 
  3287     inductive "s z_1 ... z_m"
  3288     intros
  3289       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3290       ...
  3291 
  3292   For backward compatibility, there is a wrapper allowing inductive
  3293   sets to be defined with the new package via
  3294 
  3295     inductive_set
  3296       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3297       for z_1 :: U_1 and ... and z_n :: U_m
  3298     where
  3299       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3300     | ...
  3301 
  3302   or
  3303 
  3304     inductive_set
  3305       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3306       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3307       for z_1 :: U_1 and ... and z_n :: U_m
  3308     where
  3309       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3310     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3311     | ...
  3312 
  3313   if the additional syntax "p ..." is required.
  3314 
  3315   Numerous examples can be found in the subdirectories src/HOL/Auth,
  3316   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  3317 
  3318   INCOMPATIBILITIES:
  3319 
  3320   - Since declaration and definition of inductive sets or predicates
  3321     is no longer separated, abbreviations involving the newly
  3322     introduced sets or predicates must be specified together with the
  3323     introduction rules after the 'where' keyword (see above), rather
  3324     than before the actual inductive definition.
  3325 
  3326   - The variables in induction and elimination rules are now
  3327     quantified in the order of their occurrence in the introduction
  3328     rules, rather than in alphabetical order. Since this may break
  3329     some proofs, these proofs either have to be repaired, e.g. by
  3330     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  3331     statements of the form
  3332 
  3333       case (rule_i a_i_1 ... a_i_{k_i})
  3334 
  3335     or the old order of quantification has to be restored by explicitly adding
  3336     meta-level quantifiers in the introduction rules, i.e.
  3337 
  3338       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  3339 
  3340   - The format of the elimination rules is now
  3341 
  3342       p z_1 ... z_m x_1 ... x_n ==>
  3343         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3344         ==> ... ==> P
  3345 
  3346     for predicates and
  3347 
  3348       (x_1, ..., x_n) : s z_1 ... z_m ==>
  3349         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3350         ==> ... ==> P
  3351 
  3352     for sets rather than
  3353 
  3354       x : s z_1 ... z_m ==>
  3355         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  3356         ==> ... ==> P
  3357 
  3358     This may require terms in goals to be expanded to n-tuples
  3359     (e.g. using case_tac or simplification with the split_paired_all
  3360     rule) before the above elimination rule is applicable.
  3361 
  3362   - The elimination or case analysis rules for (mutually) inductive
  3363     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  3364     list of rules "p_1_..._p_k.elims" is no longer available.
  3365 
  3366 * New package "function"/"fun" for general recursive functions,
  3367 supporting mutual and nested recursion, definitions in local contexts,
  3368 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  3369 for small examples, and the separate tutorial on the function
  3370 package. The old recdef "package" is still available as before, but
  3371 users are encouraged to use the new package.
  3372 
  3373 * Method "lexicographic_order" automatically synthesizes termination
  3374 relations as lexicographic combinations of size measures. 
  3375 
  3376 * Case-expressions allow arbitrary constructor-patterns (including
  3377 "_") and take their order into account, like in functional
  3378 programming.  Internally, this is translated into nested
  3379 case-expressions; missing cases are added and mapped to the predefined
  3380 constant "undefined". In complicated cases printing may no longer show
  3381 the original input but the internal form. Lambda-abstractions allow
  3382 the same form of pattern matching: "% pat1 => e1 | ..." is an
  3383 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  3384 variable.
  3385 
  3386 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  3387 is an abbreviation for "of_nat :: nat => int". The simplification
  3388 rules for "of_nat" have been changed to work like "int" did
  3389 previously.  Potential INCOMPATIBILITY:
  3390   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  3391   - of_nat_diff and of_nat_mult are no longer default simp rules
  3392 
  3393 * Method "algebra" solves polynomial equations over (semi)rings using
  3394 Groebner bases. The (semi)ring structure is defined by locales and the
  3395 tool setup depends on that generic context. Installing the method for
  3396 a specific type involves instantiating the locale and possibly adding
  3397 declarations for computation on the coefficients.  The method is
  3398 already instantiated for natural numbers and for the axiomatic class
  3399 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  3400 CALCULEMUS 2007 for the general principles underlying this
  3401 architecture of context-aware proof-tools.
  3402 
  3403 * Method "ferrack" implements quantifier elimination over
  3404 special-purpose dense linear orders using locales (analogous to
  3405 "algebra"). The method is already installed for class
  3406 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  3407 rat, etc.
  3408 
  3409 * Former constant "List.op @" now named "List.append".  Use ML
  3410 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  3411 circumvent possible incompatibilities when working on ML level.
  3412 
  3413 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  3414 
  3415 * New function listsum :: 'a list => 'a for arbitrary monoids.
  3416 Special syntax: "SUM x <- xs. f x" (and latex variants)
  3417 
  3418 * New syntax for Haskell-like list comprehension (input only), eg.
  3419 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  3420 
  3421 * The special syntax for function "filter" has changed from [x :
  3422 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  3423 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  3424 
  3425 * [a..b] is now defined for arbitrary linear orders.  It used to be
  3426 defined on nat only, as an abbreviation for [a..<Suc b]
  3427 INCOMPATIBILITY.
  3428 
  3429 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  3430 
  3431 * New functions "sorted" and "sort" in src/HOL/List.thy.
  3432 
  3433 * New lemma collection field_simps (an extension of ring_simps) for
  3434 manipulating (in)equations involving division. Multiplies with all
  3435 denominators that can be proved to be non-zero (in equations) or
  3436 positive/negative (in inequations).
  3437 
  3438 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  3439 have been improved and renamed to ring_simps, group_simps and
  3440 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  3441 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  3442 
  3443 * Theory Library/Commutative_Ring: switched from recdef to function
  3444 package; constants add, mul, pow now curried.  Infix syntax for
  3445 algebraic operations.
  3446 
  3447 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  3448 INCOMPATIBILITY.
  3449 
  3450 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  3451 INCOMPATIBILITY.
  3452 
  3453 * HOL/records: generalised field-update to take a function on the
  3454 field rather than the new value: r(|A := x|) is translated to A_update
  3455 (K x) r The K-combinator that is internally used is called K_record.
  3456 INCOMPATIBILITY: Usage of the plain update functions has to be
  3457 adapted.
  3458  
  3459 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  3460 * x = 0, which are required for a semiring.  Richer structures do not
  3461 inherit from semiring_0 anymore, because this property is a theorem
  3462 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  3463 there is more to prove, but this is mostly trivial.
  3464 
  3465 * Class "recpower" is generalized to arbitrary monoids, not just
  3466 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  3467 commutativity or semiring properties additionally.
  3468 
  3469 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  3470 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  3471 better use 'abbreviation'.
  3472 
  3473 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  3474 
  3475 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  3476 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  3477 significant changes for setting up numeral syntax for types:
  3478   - New constants Numeral.pred and Numeral.succ instead
  3479       of former Numeral.bin_pred and Numeral.bin_succ.
  3480   - Use integer operations instead of bin_add, bin_mult and so on.
  3481   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  3482   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  3483 
  3484 See src/HOL/Integ/IntArith.thy for an example setup.
  3485 
  3486 * Command 'normal_form' computes the normal form of a term that may
  3487 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  3488 produces ``[b, c, a]'' (without proof).  This command is suitable for
  3489 heavy-duty computations because the functions are compiled to ML
  3490 first.  Correspondingly, a method "normalization" is provided.  See
  3491 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  3492 
  3493 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  3494 25 like -->); output depends on the "iff" print_mode, the default is
  3495 "A = B" (with priority 50).
  3496 
  3497 * Relations less (<) and less_eq (<=) are also available on type bool.
  3498 Modified syntax to disallow nesting without explicit parentheses,
  3499 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  3500 INCOMPATIBILITY.
  3501 
  3502 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  3503 
  3504 * Relation composition operator "op O" now has precedence 75 and binds
  3505 stronger than union and intersection. INCOMPATIBILITY.
  3506 
  3507 * The old set interval syntax "{m..n(}" (and relatives) has been
  3508 removed.  Use "{m..<n}" (and relatives) instead.
  3509 
  3510 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  3511 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  3512 ``declare [[simproc del: neq]]''.
  3513 
  3514 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  3515 True/False.
  3516 
  3517 * Theorem Cons_eq_map_conv no longer declared as "simp".
  3518 
  3519 * Theorem setsum_mult renamed to setsum_right_distrib.
  3520 
  3521 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  3522 ``rule'' method.
  3523 
  3524 * Reimplemented methods "sat" and "satx", with several improvements:
  3525 goals no longer need to be stated as "<prems> ==> False", equivalences
  3526 (i.e. "=" on type bool) are handled, variable names of the form
  3527 "lit_<n>" are no longer reserved, significant speedup.
  3528 
  3529 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  3530 zChaff is still supported as well.
  3531 
  3532 * 'inductive' and 'datatype': provide projections of mutual rules,
  3533 bundled as foo_bar.inducts;
  3534 
  3535 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  3536 Library.
  3537 
  3538 * Library: moved theory Accessible_Part to main HOL.
  3539 
  3540 * Library: added theory Coinductive_List of potentially infinite lists
  3541 as greatest fixed-point.
  3542 
  3543 * Library: added theory AssocList which implements (finite) maps as
  3544 association lists.
  3545 
  3546 * Method "evaluation" solves goals (i.e. a boolean expression)
  3547 efficiently by compiling it to ML.  The goal is "proved" (via an
  3548 oracle) if it evaluates to True.
  3549 
  3550 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  3551 also when invoked by the simplifier.  This results in the Simplifier
  3552 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  3553 Configuration option fast_arith_split_limit=0 recovers the old
  3554 behavior.
  3555 
  3556 * Support for hex (0x20) and binary (0b1001) numerals.
  3557 
  3558 * New method: reify eqs (t), where eqs are equations for an
  3559 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  3560 parameter, computes a term s::'b and a list xs::'a list and proves the
  3561 theorem I xs s = t. This is also known as reification or quoting. The
  3562 resulting theorem is applied to the subgoal to substitute t with I xs
  3563 s.  If t is omitted, the subgoal itself is reified.
  3564 
  3565 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  3566 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  3567 where f is supposed to be a computable function (in the sense of code
  3568 generattion). The method uses reify to compute s and xs as above then
  3569 applies corr_thm and uses normalization by evaluation to "prove" f s =
  3570 r and finally gets the theorem t = r, which is again applied to the
  3571 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  3572 
  3573 * Reflection: Automatic reification now handels binding, an example is
  3574 available in src/HOL/ex/ReflectionEx.thy
  3575 
  3576 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  3577 command 'statespace' that is similar to 'record', but introduces an
  3578 abstract specification based on the locale infrastructure instead of
  3579 HOL types.  This leads to extra flexibility in composing state spaces,
  3580 in particular multiple inheritance and renaming of components.
  3581 
  3582 
  3583 *** HOL-Complex ***
  3584 
  3585 * Hyperreal: Functions root and sqrt are now defined on negative real
  3586 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  3587 Nonnegativity side conditions have been removed from many lemmas, so
  3588 that more subgoals may now be solved by simplification; potential
  3589 INCOMPATIBILITY.
  3590 
  3591 * Real: new type classes formalize real normed vector spaces and
  3592 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  3593 and norm :: 'a => real.
  3594 
  3595 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  3596 reals into other types. The overloaded constant Reals :: 'a set is now
  3597 defined as range of_real; potential INCOMPATIBILITY.
  3598 
  3599 * Real: proper support for ML code generation, including 'quickcheck'.
  3600 Reals are implemented as arbitrary precision rationals.
  3601 
  3602 * Hyperreal: Several constants that previously worked only for the
  3603 reals have been generalized, so they now work over arbitrary vector
  3604 spaces. Type annotations may need to be added in some cases; potential
  3605 INCOMPATIBILITY.
  3606 
  3607   Infinitesimal  :: ('a::real_normed_vector) star set
  3608   HFinite        :: ('a::real_normed_vector) star set
  3609   HInfinite      :: ('a::real_normed_vector) star set
  3610   approx         :: ('a::real_normed_vector) star => 'a star => bool
  3611   monad          :: ('a::real_normed_vector) star => 'a star set
  3612   galaxy         :: ('a::real_normed_vector) star => 'a star set
  3613   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  3614   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  3615   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  3616   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  3617   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  3618   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  3619   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  3620   sgn            :: 'a::real_normed_vector => 'a
  3621   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  3622 
  3623 * Complex: Some complex-specific constants are now abbreviations for
  3624 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  3625 hnorm.  Other constants have been entirely removed in favor of the
  3626 polymorphic versions (INCOMPATIBILITY):
  3627 
  3628   approx        <-- capprox
  3629   HFinite       <-- CFinite
  3630   HInfinite     <-- CInfinite
  3631   Infinitesimal <-- CInfinitesimal
  3632   monad         <-- cmonad
  3633   galaxy        <-- cgalaxy
  3634   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  3635   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  3636   (ns)deriv     <-- (ns)cderiv
  3637 
  3638 
  3639 *** HOL-Algebra ***
  3640 
  3641 * Formalisation of ideals and the quotient construction over rings.
  3642 
  3643 * Order and lattice theory no longer based on records.
  3644 INCOMPATIBILITY.
  3645 
  3646 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  3647 greatest_closed.  INCOMPATIBILITY.
  3648 
  3649 * Method algebra is now set up via an attribute.  For examples see
  3650 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  3651 of algebraic structures.
  3652 
  3653 * Renamed theory CRing to Ring.
  3654 
  3655 
  3656 *** HOL-Nominal ***
  3657 
  3658 * Substantial, yet incomplete support for nominal datatypes (binding
  3659 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  3660 src/HOL/Nominal/Examples.  Prospective users should consult
  3661 http://isabelle.in.tum.de/nominal/
  3662 
  3663 
  3664 *** ML ***
  3665 
  3666 * ML basics: just one true type int, which coincides with IntInf.int
  3667 (even on SML/NJ).
  3668 
  3669 * ML within Isar: antiquotations allow to embed statically-checked
  3670 formal entities in the source, referring to the context available at
  3671 compile-time.  For example:
  3672 
  3673 ML {* @{sort "{zero,one}"} *}
  3674 ML {* @{typ "'a => 'b"} *}
  3675 ML {* @{term "%x. x"} *}
  3676 ML {* @{prop "x == y"} *}
  3677 ML {* @{ctyp "'a => 'b"} *}
  3678 ML {* @{cterm "%x. x"} *}
  3679 ML {* @{cprop "x == y"} *}
  3680 ML {* @{thm asm_rl} *}
  3681 ML {* @{thms asm_rl} *}
  3682 ML {* @{type_name c} *}
  3683 ML {* @{type_syntax c} *}
  3684 ML {* @{const_name c} *}
  3685 ML {* @{const_syntax c} *}
  3686 ML {* @{context} *}
  3687 ML {* @{theory} *}
  3688 ML {* @{theory Pure} *}
  3689 ML {* @{theory_ref} *}
  3690 ML {* @{theory_ref Pure} *}
  3691 ML {* @{simpset} *}
  3692 ML {* @{claset} *}
  3693 ML {* @{clasimpset} *}
  3694 
  3695 The same works for sources being ``used'' within an Isar context.
  3696 
  3697 * ML in Isar: improved error reporting; extra verbosity with
  3698 ML_Context.trace enabled.
  3699 
  3700 * Pure/General/table.ML: the join operations now works via exceptions
  3701 DUP/SAME instead of type option. This is simpler in simple cases, and
  3702 admits slightly more efficient complex applications.
  3703 
  3704 * Pure: 'advanced' translation functions (parse_translation etc.) now
  3705 use Context.generic instead of just theory.
  3706 
  3707 * Pure: datatype Context.generic joins theory/Proof.context and
  3708 provides some facilities for code that works in either kind of
  3709 context, notably GenericDataFun for uniform theory and proof data.
  3710 
  3711 * Pure: simplified internal attribute type, which is now always
  3712 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  3713 local (Proof.context) attributes have been discontinued, while
  3714 minimizing code duplication. Thm.rule_attribute and
  3715 Thm.declaration_attribute build canonical attributes; see also structure
  3716 Context for further operations on Context.generic, notably
  3717 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  3718 declarations and definitions.
  3719 
  3720 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  3721 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  3722 init only required for impure data. INCOMPATIBILITY: empty really need
  3723 to be empty (no dependencies on theory content!)
  3724 
  3725 * Pure/kernel: consts certification ignores sort constraints given in
  3726 signature declarations. (This information is not relevant to the
  3727 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  3728 potential INCOMPATIBILITY.
  3729 
  3730 * Pure: axiomatic type classes are now purely definitional, with
  3731 explicit proofs of class axioms and super class relations performed
  3732 internally. See Pure/axclass.ML for the main internal interfaces --
  3733 notably AxClass.define_class supercedes AxClass.add_axclass, and
  3734 AxClass.axiomatize_class/classrel/arity supersede
  3735 Sign.add_classes/classrel/arities.
  3736 
  3737 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  3738 global/local versions on theory vs. Proof.context have been
  3739 discontinued; Attrib.syntax and Method.syntax have been adapted
  3740 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  3741 attributes, methods, etc.
  3742 
  3743 * Pure: several functions of signature "... -> theory -> theory * ..."
  3744 have been reoriented to "... -> theory -> ... * theory" in order to
  3745 allow natural usage in combination with the ||>, ||>>, |-> and
  3746 fold_map combinators.
  3747 
  3748 * Pure: official theorem names (closed derivations) and additional
  3749 comments (tags) are now strictly separate.  Name hints -- which are
  3750 maintained as tags -- may be attached any time without affecting the
  3751 derivation.
  3752 
  3753 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  3754 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  3755 achieve the old behaviour.
  3756 
  3757 * Pure: the "Goal" constant is now called "prop", supporting a
  3758 slightly more general idea of ``protecting'' meta-level rule
  3759 statements.
  3760 
  3761 * Pure: Logic.(un)varify only works in a global context, which is now
  3762 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  3763 Logic.legacy_(un)varify as temporary workaround.
  3764 
  3765 * Pure: structure Name provides scalable operations for generating
  3766 internal variable names, notably Name.variants etc.  This replaces
  3767 some popular functions from term.ML:
  3768 
  3769   Term.variant		->  Name.variant
  3770   Term.variantlist	->  Name.variant_list
  3771   Term.invent_names	->  Name.invent_list
  3772 
  3773 Note that low-level renaming rarely occurs in new code -- operations
  3774 from structure Variable are used instead (see below).
  3775 
  3776 * Pure: structure Variable provides fundamental operations for proper
  3777 treatment of fixed/schematic variables in a context.  For example,
  3778 Variable.import introduces fixes for schematics of given facts and
  3779 Variable.export reverses the effect (up to renaming) -- this replaces
  3780 various freeze_thaw operations.
  3781 
  3782 * Pure: structure Goal provides simple interfaces for
  3783 init/conclude/finish and tactical prove operations (replacing former
  3784 Tactic.prove).  Goal.prove is the canonical way to prove results
  3785 within a given context; Goal.prove_global is a degraded version for
  3786 theory level goals, including a global Drule.standard.  Note that
  3787 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  3788 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  3789 in a locale context).
  3790 
  3791 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  3792 and type checking (Syntax.check_term etc.), with common combinations
  3793 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  3794 which are considered legacy and await removal.
  3795 
  3796 * Pure/Syntax: generic interfaces for type unchecking
  3797 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  3798 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  3799 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  3800 available for convenience, but refer to the very same operations using
  3801 a mere theory instead of a full context.
  3802 
  3803 * Isar: simplified treatment of user-level errors, using exception
  3804 ERROR of string uniformly.  Function error now merely raises ERROR,
  3805 without any side effect on output channels.  The Isar toplevel takes
  3806 care of proper display of ERROR exceptions.  ML code may use plain
  3807 handle/can/try; cat_error may be used to concatenate errors like this:
  3808 
  3809   ... handle ERROR msg => cat_error msg "..."
  3810 
  3811 Toplevel ML code (run directly or through the Isar toplevel) may be
  3812 embedded into the Isar toplevel with exception display/debug like
  3813 this:
  3814 
  3815   Isar.toplevel (fn () => ...)
  3816 
  3817 INCOMPATIBILITY, removed special transform_error facilities, removed
  3818 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  3819 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  3820 -- use plain ERROR instead.
  3821 
  3822 * Isar: theory setup now has type (theory -> theory), instead of a
  3823 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  3824 
  3825 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  3826 ProofContext.debug/verbose flags.
  3827 
  3828 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  3829 theory before entering a proof state.  Transactions now always see a
  3830 quasi-functional intermediate checkpoint, both in interactive and
  3831 batch mode.
  3832 
  3833 * Isar: simplified interfaces for outer syntax.  Renamed
  3834 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  3835 OuterSyntax.add_parsers -- this functionality is now included in
  3836 OuterSyntax.command etc.  INCOMPATIBILITY.
  3837 
  3838 * Simplifier: the simpset of a running simplification process now
  3839 contains a proof context (cf. Simplifier.the_context), which is the
  3840 very context that the initial simpset has been retrieved from (by
  3841 simpset_of/local_simpset_of).  Consequently, all plug-in components
  3842 (solver, looper etc.) may depend on arbitrary proof data.
  3843 
  3844 * Simplifier.inherit_context inherits the proof context (plus the
  3845 local bounds) of the current simplification process; any simproc
  3846 etc. that calls the Simplifier recursively should do this!  Removed
  3847 former Simplifier.inherit_bounds, which is already included here --
  3848 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  3849 specify an explicit context using Simplifier.context/theory_context.
  3850 
  3851 * Simplifier/Classical Reasoner: more abstract interfaces
  3852 change_simpset/claset for modifying the simpset/claset reference of a
  3853 theory; raw versions simpset/claset_ref etc. have been discontinued --
  3854 INCOMPATIBILITY.
  3855 
  3856 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  3857 "Trueprop" etc.
  3858 
  3859 
  3860 *** System ***
  3861 
  3862 * settings: the default heap location within ISABELLE_HOME_USER now
  3863 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  3864 Isabelle installations.
  3865 
  3866 * isabelle-process: option -S (secure mode) disables some critical
  3867 operations, notably runtime compilation and evaluation of ML source
  3868 code.
  3869 
  3870 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  3871 
  3872 * Support for parallel execution, using native multicore support of
  3873 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  3874 independent theories, according to the given theory header
  3875 specifications. The maximum number of worker threads is specified via
  3876 usedir option -M or the "max-threads" setting in Proof General. A
  3877 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  3878 to 6 on a 8-core machine.  User-code needs to observe certain
  3879 guidelines for thread-safe programming, see appendix A in the Isar
  3880 Implementation manual.
  3881 
  3882 
  3883 
  3884 New in Isabelle2005 (October 2005)
  3885 ----------------------------------
  3886 
  3887 *** General ***
  3888 
  3889 * Theory headers: the new header syntax for Isar theories is
  3890 
  3891   theory <name>
  3892   imports <theory1> ... <theoryN>
  3893   uses <file1> ... <fileM>
  3894   begin
  3895 
  3896 where the 'uses' part is optional.  The previous syntax
  3897 
  3898   theory <name> = <theory1> + ... + <theoryN>:
  3899 
  3900 will disappear in the next release.  Use isatool fixheaders to convert
  3901 existing theory files.  Note that there is no change in ancient
  3902 non-Isar theories now, but these will disappear soon.
  3903 
  3904 * Theory loader: parent theories can now also be referred to via
  3905 relative and absolute paths.
  3906 
  3907 * Command 'find_theorems' searches for a list of criteria instead of a
  3908 list of constants. Known criteria are: intro, elim, dest, name:string,
  3909 simp:term, and any term. Criteria can be preceded by '-' to select
  3910 theorems that do not match. Intro, elim, dest select theorems that
  3911 match the current goal, name:s selects theorems whose fully qualified
  3912 name contain s, and simp:term selects all simplification rules whose
  3913 lhs match term.  Any other term is interpreted as pattern and selects
  3914 all theorems matching the pattern. Available in ProofGeneral under
  3915 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  3916 
  3917   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  3918 
  3919 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  3920 matching the current goal as introduction rule and not having "HOL."
  3921 in their name (i.e. not being defined in theory HOL).
  3922 
  3923 * Command 'thms_containing' has been discontinued in favour of
  3924 'find_theorems'; INCOMPATIBILITY.
  3925 
  3926 * Communication with Proof General is now 8bit clean, which means that
  3927 Unicode text in UTF-8 encoding may be used within theory texts (both
  3928 formal and informal parts).  Cf. option -U of the Isabelle Proof
  3929 General interface.  Here are some simple examples (cf. src/HOL/ex):
  3930 
  3931   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  3932   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  3933 
  3934 * Improved efficiency of the Simplifier and, to a lesser degree, the
  3935 Classical Reasoner.  Typical big applications run around 2 times
  3936 faster.
  3937 
  3938 
  3939 *** Document preparation ***
  3940 
  3941 * Commands 'display_drafts' and 'print_drafts' perform simple output
  3942 of raw sources.  Only those symbols that do not require additional
  3943 LaTeX packages (depending on comments in isabellesym.sty) are
  3944 displayed properly, everything else is left verbatim.  isatool display
  3945 and isatool print are used as front ends (these are subject to the
  3946 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  3947 
  3948 * Command tags control specific markup of certain regions of text,
  3949 notably folding and hiding.  Predefined tags include "theory" (for
  3950 theory begin and end), "proof" for proof commands, and "ML" for
  3951 commands involving ML code; the additional tags "visible" and
  3952 "invisible" are unused by default.  Users may give explicit tag
  3953 specifications in the text, e.g. ''by %invisible (auto)''.  The
  3954 interpretation of tags is determined by the LaTeX job during document
  3955 preparation: see option -V of isatool usedir, or options -n and -t of
  3956 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  3957 \isadroptag.
  3958 
  3959 Several document versions may be produced at the same time via isatool
  3960 usedir (the generated index.html will link all of them).  Typical
  3961 specifications include ''-V document=theory,proof,ML'' to present
  3962 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  3963 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  3964 these parts without any formal replacement text.  The Isabelle site
  3965 default settings produce ''document'' and ''outline'' versions as
  3966 specified above.
  3967 
  3968 * Several new antiquotations:
  3969 
  3970   @{term_type term} prints a term with its type annotated;
  3971 
  3972   @{typeof term} prints the type of a term;
  3973 
  3974   @{const const} is the same as @{term const}, but checks that the
  3975   argument is a known logical constant;
  3976 
  3977   @{term_style style term} and @{thm_style style thm} print a term or
  3978   theorem applying a "style" to it
  3979 
  3980   @{ML text}
  3981 
  3982 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  3983 definitions, equations, inequations etc., 'concl' printing only the
  3984 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  3985 to print the specified premise.  TermStyle.add_style provides an ML
  3986 interface for introducing further styles.  See also the "LaTeX Sugar"
  3987 document practical applications.  The ML antiquotation prints
  3988 type-checked ML expressions verbatim.
  3989 
  3990 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  3991 and 'text' support optional locale specification '(in loc)', which
  3992 specifies the default context for interpreting antiquotations.  For
  3993 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  3994 
  3995 * Option 'locale=NAME' of antiquotations specifies an alternative
  3996 context interpreting the subsequent argument.  For example: @{thm
  3997 [locale=lattice] inf_assoc}.
  3998 
  3999 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4000 a proof context.
  4001 
  4002 * Proper output of antiquotations for theory commands involving a
  4003 proof context (such as 'locale' or 'theorem (in loc) ...').
  4004 
  4005 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4006 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4007 
  4008 * isatool usedir: new option -C (default true) controls whether option
  4009 -D should include a copy of the original document directory; -C false
  4010 prevents unwanted effects such as copying of administrative CVS data.
  4011 
  4012 
  4013 *** Pure ***
  4014 
  4015 * Considerably improved version of 'constdefs' command.  Now performs
  4016 automatic type-inference of declared constants; additional support for
  4017 local structure declarations (cf. locales and HOL records), see also
  4018 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4019 sequential dependencies of definitions within a single 'constdefs'
  4020 section; moreover, the declared name needs to be an identifier.  If
  4021 all fails, consider to fall back on 'consts' and 'defs' separately.
  4022 
  4023 * Improved indexed syntax and implicit structures.  First of all,
  4024 indexed syntax provides a notational device for subscripted
  4025 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4026 expressions.  Secondly, in a local context with structure
  4027 declarations, number indexes \<^sub>n or the empty index (default
  4028 number 1) refer to a certain fixed variable implicitly; option
  4029 show_structs controls printing of implicit structures.  Typical
  4030 applications of these concepts involve record types and locales.
  4031 
  4032 * New command 'no_syntax' removes grammar declarations (and
  4033 translations) resulting from the given syntax specification, which is
  4034 interpreted in the same manner as for the 'syntax' command.
  4035 
  4036 * 'Advanced' translation functions (parse_translation etc.) may depend
  4037 on the signature of the theory context being presently used for
  4038 parsing/printing, see also isar-ref manual.
  4039 
  4040 * Improved 'oracle' command provides a type-safe interface to turn an
  4041 ML expression of type theory -> T -> term into a primitive rule of
  4042 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4043 is already included here); see also FOL/ex/IffExample.thy;
  4044 INCOMPATIBILITY.
  4045 
  4046 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4047 before); "cI" is no longer bound, use "c.intro" instead.
  4048 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4049 axclasses vs. locales.
  4050 
  4051 * Improved internal renaming of symbolic identifiers -- attach primes
  4052 instead of base 26 numbers.
  4053 
  4054 * New flag show_question_marks controls printing of leading question
  4055 marks in schematic variable names.
  4056 
  4057 * In schematic variable names, *any* symbol following \<^isub> or
  4058 \<^isup> is now treated as part of the base name.  For example, the
  4059 following works without printing of awkward ".0" indexes:
  4060 
  4061   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4062     by simp
  4063 
  4064 * Inner syntax includes (*(*nested*) comments*).
  4065 
  4066 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4067 annotations as "(00...)".
  4068 
  4069 * Clear separation of logical types and nonterminals, where the latter
  4070 may only occur in 'syntax' specifications or type abbreviations.
  4071 Before that distinction was only partially implemented via type class
  4072 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4073 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4074 exotic syntax specifications may require further adaption
  4075 (e.g. Cube/Cube.thy).
  4076 
  4077 * Removed obsolete type class "logic", use the top sort {} instead.
  4078 Note that non-logical types should be declared as 'nonterminals'
  4079 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4080 specifications.
  4081 
  4082 * Attributes 'induct' and 'cases': type or set names may now be
  4083 locally fixed variables as well.
  4084 
  4085 * Simplifier: can now control the depth to which conditional rewriting
  4086 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4087 Limit.
  4088 
  4089 * Simplifier: simplification procedures may now take the current
  4090 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4091 interface), which is very useful for calling the Simplifier
  4092 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4093 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4094 low-level mk_simproc no longer applies Logic.varify internally, to
  4095 allow for use in a context of fixed variables.
  4096 
  4097 * thin_tac now works even if the assumption being deleted contains !!
  4098 or ==>.  More generally, erule now works even if the major premise of
  4099 the elimination rule contains !! or ==>.
  4100 
  4101 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4102 
  4103 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4104 from Pure, which contains all common declarations already.  Both
  4105 theories are defined via plain Isabelle/Isar .thy files.
  4106 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4107 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4108 use isatool fixcpure to adapt your theory and ML sources.
  4109 
  4110 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4111 selections of theorems in named facts via index ranges.
  4112 
  4113 * 'print_theorems': in theory mode, really print the difference
  4114 wrt. the last state (works for interactive theory development only),
  4115 in proof mode print all local facts (cf. 'print_facts');
  4116 
  4117 * 'hide': option '(open)' hides only base names.
  4118 
  4119 * More efficient treatment of intermediate checkpoints in interactive
  4120 theory development.
  4121 
  4122 * Code generator is now invoked via code_module (incremental code
  4123 generation) and code_library (modular code generation, ML structures
  4124 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4125 must be quoted when used as identifiers.
  4126 
  4127 * New 'value' command for reading, evaluating and printing terms using
  4128 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4129 quoted when used as identifier.
  4130 
  4131 
  4132 *** Locales ***
  4133 
  4134 * New commands for the interpretation of locale expressions in
  4135 theories (1), locales (2) and proof contexts (3).  These generate
  4136 proof obligations from the expression specification.  After the
  4137 obligations have been discharged, theorems of the expression are added
  4138 to the theory, target locale or proof context.  The synopsis of the
  4139 commands is a follows:
  4140 
  4141   (1) interpretation expr inst
  4142   (2) interpretation target < expr
  4143   (3) interpret expr inst
  4144 
  4145 Interpretation in theories and proof contexts require a parameter
  4146 instantiation of terms from the current context.  This is applied to
  4147 specifications and theorems of the interpreted expression.
  4148 Interpretation in locales only permits parameter renaming through the
  4149 locale expression.  Interpretation is smart in that interpretations
  4150 that are active already do not occur in proof obligations, neither are
  4151 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4152 inspect active interpretations of a particular locale.  For details,
  4153 see the Isar Reference manual.  Examples can be found in
  4154 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4155 
  4156 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4157 'interpret' instead.
  4158 
  4159 * New context element 'constrains' for adding type constraints to
  4160 parameters.
  4161 
  4162 * Context expressions: renaming of parameters with syntax
  4163 redeclaration.
  4164 
  4165 * Locale declaration: 'includes' disallowed.
  4166 
  4167 * Proper static binding of attribute syntax -- i.e. types / terms /
  4168 facts mentioned as arguments are always those of the locale definition
  4169 context, independently of the context of later invocations.  Moreover,
  4170 locale operations (renaming and type / term instantiation) are applied
  4171 to attribute arguments as expected.
  4172 
  4173 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4174 actual attributes; rare situations may require Attrib.attribute to
  4175 embed those attributes into Attrib.src that lack concrete syntax.
  4176 Attribute implementations need to cooperate properly with the static
  4177 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4178 Attrib.XXX_thm etc. already do the right thing without further
  4179 intervention.  Only unusual applications -- such as "where" or "of"
  4180 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4181 on the context and the facts involved -- may have to assign parsed
  4182 values to argument tokens explicitly.
  4183 
  4184 * Changed parameter management in theorem generation for long goal
  4185 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4186 theorem statement in rare situations.
  4187 
  4188 * Locale inspection command 'print_locale' omits notes elements.  Use
  4189 'print_locale!' to have them included in the output.
  4190 
  4191 
  4192 *** Provers ***
  4193 
  4194 * Provers/hypsubst.ML: improved version of the subst method, for
  4195 single-step rewriting: it now works in bound variable contexts. New is
  4196 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4197 rewrite a different subterm than the original subst method, which is
  4198 still available as 'simplesubst'.
  4199 
  4200 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4201 and quasi orders.
  4202 
  4203 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4204 reflexive-transitive closure of relations.
  4205 
  4206 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4207 limit (previously hard-coded with a value of 20) user-definable.
  4208 
  4209 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4210 is peformed already.  Object-logics merely need to finish their
  4211 initial simpset configuration as before.  INCOMPATIBILITY.
  4212 
  4213 
  4214 *** HOL ***
  4215 
  4216 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4217 
  4218   syntax (epsilon)
  4219     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4220 
  4221 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4222 and x-symbol; use option '-m epsilon' to get it actually printed.
  4223 Moreover, the mathematically important symbolic identifier \<epsilon>
  4224 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4225 
  4226 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  4227 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  4228 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  4229 support corresponding Isar calculations.
  4230 
  4231 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  4232 instead of ":".
  4233 
  4234 * theory SetInterval: changed the syntax for open intervals:
  4235 
  4236   Old       New
  4237   {..n(}    {..<n}
  4238   {)n..}    {n<..}
  4239   {m..n(}   {m..<n}
  4240   {)m..n}   {m<..n}
  4241   {)m..n(}  {m<..<n}
  4242 
  4243 The old syntax is still supported but will disappear in the next
  4244 release.  For conversion use the following Emacs search and replace
  4245 patterns (these are not perfect but work quite well):
  4246 
  4247   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  4248   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  4249 
  4250 * Theory Commutative_Ring (in Library): method comm_ring for proving
  4251 equalities in commutative rings; method 'algebra' provides a generic
  4252 interface.
  4253 
  4254 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  4255 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  4256 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  4257 be a tuple pattern.
  4258 
  4259 Some new syntax forms are available:
  4260 
  4261   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  4262   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  4263   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  4264   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  4265 
  4266 The latter form "\<Sum>x < k. e" used to be based on a separate
  4267 function "Summation", which has been discontinued.
  4268 
  4269 * theory Finite_Set: in structured induction proofs, the insert case
  4270 is now 'case (insert x F)' instead of the old counterintuitive 'case
  4271 (insert F x)'.
  4272 
  4273 * The 'refute' command has been extended to support a much larger
  4274 fragment of HOL, including axiomatic type classes, constdefs and
  4275 typedefs, inductive datatypes and recursion.
  4276 
  4277 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  4278 Requires zChaff with proof generation to be installed.  See
  4279 HOL/ex/SAT_Examples.thy for examples.
  4280 
  4281 * Datatype induction via method 'induct' now preserves the name of the
  4282 induction variable. For example, when proving P(xs::'a list) by
  4283 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  4284 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  4285 in unstructured proof scripts.
  4286 
  4287 * Reworked implementation of records.  Improved scalability for
  4288 records with many fields, avoiding performance problems for type
  4289 inference. Records are no longer composed of nested field types, but
  4290 of nested extension types. Therefore the record type only grows linear
  4291 in the number of extensions and not in the number of fields.  The
  4292 top-level (users) view on records is preserved.  Potential
  4293 INCOMPATIBILITY only in strange cases, where the theory depends on the
  4294 old record representation. The type generated for a record is called
  4295 <record_name>_ext_type.
  4296 
  4297 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  4298 proofs triggered by a record definition or a simproc (if
  4299 quick_and_dirty is enabled).  Definitions of large records can take
  4300 quite long.
  4301 
  4302 New simproc record_upd_simproc for simplification of multiple record
  4303 updates enabled by default.  Moreover, trivial updates are also
  4304 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  4305 occasionally, since simplification is more powerful by default.
  4306 
  4307 * typedef: proper support for polymorphic sets, which contain extra
  4308 type-variables in the term.
  4309 
  4310 * Simplifier: automatically reasons about transitivity chains
  4311 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  4312 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  4313 old proofs break occasionally as simplification may now solve more
  4314 goals than previously.
  4315 
  4316 * Simplifier: converts x <= y into x = y if assumption y <= x is
  4317 present.  Works for all partial orders (class "order"), in particular
  4318 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  4319 just like y <= x.
  4320 
  4321 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  4322 bound variable or a constant then the let is unfolded.  Otherwise
  4323 first a is simplified to b, and then f b is simplified to g. If
  4324 possible we abstract b from g arriving at "let x = b in h x",
  4325 otherwise we unfold the let and arrive at g.  The simproc can be
  4326 enabled/disabled by the reference use_let_simproc.  Potential
  4327 INCOMPATIBILITY since simplification is more powerful by default.
  4328 
  4329 * Classical reasoning: the meson method now accepts theorems as arguments.
  4330 
  4331 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  4332 jobs to provide advice on the provability of subgoals.
  4333 
  4334 * Theory OrderedGroup and Ring_and_Field: various additions and
  4335 improvements to faciliate calculations involving equalities and
  4336 inequalities.
  4337 
  4338 The following theorems have been eliminated or modified
  4339 (INCOMPATIBILITY):
  4340 
  4341   abs_eq             now named abs_of_nonneg
  4342   abs_of_ge_0        now named abs_of_nonneg
  4343   abs_minus_eq       now named abs_of_nonpos
  4344   imp_abs_id         now named abs_of_nonneg
  4345   imp_abs_neg_id     now named abs_of_nonpos
  4346   mult_pos           now named mult_pos_pos
  4347   mult_pos_le        now named mult_nonneg_nonneg
  4348   mult_pos_neg_le    now named mult_nonneg_nonpos
  4349   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  4350   mult_neg           now named mult_neg_neg
  4351   mult_neg_le        now named mult_nonpos_nonpos
  4352 
  4353 * The following lemmas in Ring_and_Field have been added to the simplifier:
  4354      
  4355      zero_le_square
  4356      not_square_less_zero 
  4357 
  4358   The following lemmas have been deleted from Real/RealPow:
  4359   
  4360      realpow_zero_zero
  4361      realpow_two
  4362      realpow_less
  4363      zero_le_power
  4364      realpow_two_le
  4365      abs_realpow_two
  4366      realpow_two_abs     
  4367 
  4368 * Theory Parity: added rules for simplifying exponents.
  4369 
  4370 * Theory List:
  4371 
  4372 The following theorems have been eliminated or modified
  4373 (INCOMPATIBILITY):
  4374 
  4375   list_all_Nil       now named list_all.simps(1)
  4376   list_all_Cons      now named list_all.simps(2)
  4377   list_all_conv      now named list_all_iff
  4378   set_mem_eq         now named mem_iff
  4379 
  4380 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  4381 asymptotic "big O" calculations.  See the notes in BigO.thy.
  4382 
  4383 
  4384 *** HOL-Complex ***
  4385 
  4386 * Theory RealDef: better support for embedding natural numbers and
  4387 integers in the reals.
  4388 
  4389 The following theorems have been eliminated or modified
  4390 (INCOMPATIBILITY):
  4391 
  4392   exp_ge_add_one_self  now requires no hypotheses
  4393   real_of_int_add      reversed direction of equality (use [symmetric])
  4394   real_of_int_minus    reversed direction of equality (use [symmetric])
  4395   real_of_int_diff     reversed direction of equality (use [symmetric])
  4396   real_of_int_mult     reversed direction of equality (use [symmetric])
  4397 
  4398 * Theory RComplete: expanded support for floor and ceiling functions.
  4399 
  4400 * Theory Ln is new, with properties of the natural logarithm
  4401 
  4402 * Hyperreal: There is a new type constructor "star" for making
  4403 nonstandard types.  The old type names are now type synonyms:
  4404 
  4405   hypreal = real star
  4406   hypnat = nat star
  4407   hcomplex = complex star
  4408 
  4409 * Hyperreal: Many groups of similarly-defined constants have been
  4410 replaced by polymorphic versions (INCOMPATIBILITY):
  4411 
  4412   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  4413 
  4414   starset      <-- starsetNat, starsetC
  4415   *s*          <-- *sNat*, *sc*
  4416   starset_n    <-- starsetNat_n, starsetC_n
  4417   *sn*         <-- *sNatn*, *scn*
  4418   InternalSets <-- InternalNatSets, InternalCSets
  4419 
  4420   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  4421   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  4422   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  4423   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  4424   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  4425 
  4426 * Hyperreal: Many type-specific theorems have been removed in favor of
  4427 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  4428 
  4429   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  4430   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  4431   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  4432   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  4433   right_minus <-- hypreal_add_minus
  4434   left_minus <-- {hypreal,hcomplex}_add_minus_left
  4435   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  4436   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  4437   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  4438   mult_1_right <-- hcomplex_mult_one_right
  4439   mult_zero_left <-- hcomplex_mult_zero_left
  4440   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  4441   right_distrib <-- hypnat_add_mult_distrib2
  4442   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  4443   right_inverse <-- hypreal_mult_inverse
  4444   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  4445   order_refl <-- {hypreal,hypnat}_le_refl
  4446   order_trans <-- {hypreal,hypnat}_le_trans
  4447   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  4448   order_less_le <-- {hypreal,hypnat}_less_le
  4449   linorder_linear <-- {hypreal,hypnat}_le_linear
  4450   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  4451   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  4452   add_nonneg_nonneg <-- hypreal_le_add_order
  4453 
  4454 * Hyperreal: Separate theorems having to do with type-specific
  4455 versions of constants have been merged into theorems that apply to the
  4456 new polymorphic constants (INCOMPATIBILITY):
  4457 
  4458   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  4459   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  4460   STAR_Un <-- {STAR,NatStar,STARC}_Un
  4461   STAR_Int <-- {STAR,NatStar,STARC}_Int
  4462   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  4463   STAR_subset <-- {STAR,NatStar,STARC}_subset
  4464   STAR_mem <-- {STAR,NatStar,STARC}_mem
  4465   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  4466   STAR_diff <-- {STAR,STARC}_diff
  4467   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  4468     STARC_hcomplex_of_complex}_image_subset
  4469   starset_n_Un <-- starset{Nat,C}_n_Un
  4470   starset_n_Int <-- starset{Nat,C}_n_Int
  4471   starset_n_Compl <-- starset{Nat,C}_n_Compl
  4472   starset_n_diff <-- starset{Nat,C}_n_diff
  4473   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  4474   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  4475   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  4476   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  4477   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  4478   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  4479   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  4480   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  4481   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  4482   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  4483   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  4484   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  4485   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  4486   starfun_diff <-- starfun{C,RC,CR}_diff
  4487   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  4488   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  4489   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  4490   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  4491   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  4492   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  4493   starfun_Id <-- starfunC_Id
  4494   starfun_approx <-- starfun{Nat,CR}_approx
  4495   starfun_capprox <-- starfun{C,RC}_capprox
  4496   starfun_abs <-- starfunNat_rabs
  4497   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  4498   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  4499   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  4500   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  4501   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  4502   starfun_add_approx <-- starfunCR_add_approx
  4503   starfun_inverse_inverse <-- starfunC_inverse_inverse
  4504   starfun_divide <-- starfun{C,CR,RC}_divide
  4505   starfun_n <-- starfun{Nat,C}_n
  4506   starfun_n_mult <-- starfun{Nat,C}_n_mult
  4507   starfun_n_add <-- starfun{Nat,C}_n_add
  4508   starfun_n_add_minus <-- starfunNat_n_add_minus
  4509   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  4510   starfun_n_minus <-- starfun{Nat,C}_n_minus
  4511   starfun_n_eq <-- starfun{Nat,C}_n_eq
  4512 
  4513   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  4514   star_n_minus <-- {hypreal,hcomplex}_minus
  4515   star_n_diff <-- {hypreal,hcomplex}_diff
  4516   star_n_mult <-- {hypreal,hcomplex}_mult
  4517   star_n_inverse <-- {hypreal,hcomplex}_inverse
  4518   star_n_le <-- {hypreal,hypnat}_le
  4519   star_n_less <-- {hypreal,hypnat}_less
  4520   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  4521   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  4522   star_n_abs <-- hypreal_hrabs
  4523   star_n_divide <-- hcomplex_divide
  4524 
  4525   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  4526   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  4527   star_of_diff <-- hypreal_of_real_diff
  4528   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  4529   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  4530   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  4531   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  4532   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  4533   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  4534   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  4535   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  4536   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  4537   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  4538   star_of_number_of <-- {hypreal,hcomplex}_number_of
  4539   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  4540   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  4541   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  4542   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  4543   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  4544   star_of_power <-- hypreal_of_real_power
  4545   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  4546 
  4547 * Hyperreal: new method "transfer" that implements the transfer
  4548 principle of nonstandard analysis. With a subgoal that mentions
  4549 nonstandard types like "'a star", the command "apply transfer"
  4550 replaces it with an equivalent one that mentions only standard types.
  4551 To be successful, all free variables must have standard types; non-
  4552 standard variables must have explicit universal quantifiers.
  4553 
  4554 * Hyperreal: A theory of Taylor series.
  4555 
  4556 
  4557 *** HOLCF ***
  4558 
  4559 * Discontinued special version of 'constdefs' (which used to support
  4560 continuous functions) in favor of the general Pure one with full
  4561 type-inference.
  4562 
  4563 * New simplification procedure for solving continuity conditions; it
  4564 is much faster on terms with many nested lambda abstractions (cubic
  4565 instead of exponential time).
  4566 
  4567 * New syntax for domain package: selector names are now optional.
  4568 Parentheses should be omitted unless argument is lazy, for example:
  4569 
  4570   domain 'a stream = cons "'a" (lazy "'a stream")
  4571 
  4572 * New command 'fixrec' for defining recursive functions with pattern
  4573 matching; defining multiple functions with mutual recursion is also
  4574 supported.  Patterns may include the constants cpair, spair, up, sinl,
  4575 sinr, or any data constructor defined by the domain package. The given
  4576 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  4577 syntax and examples.
  4578 
  4579 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  4580 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  4581 but the proof obligation additionally includes an admissibility
  4582 requirement. The packages generate instances of class cpo or pcpo,
  4583 with continuity and strictness theorems for Rep and Abs.
  4584 
  4585 * HOLCF: Many theorems have been renamed according to a more standard naming
  4586 scheme (INCOMPATIBILITY):
  4587 
  4588   foo_inject:  "foo$x = foo$y ==> x = y"
  4589   foo_eq:      "(foo$x = foo$y) = (x = y)"
  4590   foo_less:    "(foo$x << foo$y) = (x << y)"
  4591   foo_strict:  "foo$UU = UU"
  4592   foo_defined: "... ==> foo$x ~= UU"
  4593   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  4594 
  4595 
  4596 *** ZF ***
  4597 
  4598 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  4599 including the First Isomorphism Theorem (on quotienting by the kernel
  4600 of a homomorphism).
  4601 
  4602 * ZF/Simplifier: install second copy of type solver that actually
  4603 makes use of TC rules declared to Isar proof contexts (or locales);
  4604 the old version is still required for ML proof scripts.
  4605 
  4606 
  4607 *** Cube ***
  4608 
  4609 * Converted to Isar theory format; use locales instead of axiomatic
  4610 theories.
  4611 
  4612 
  4613 *** ML ***
  4614 
  4615 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  4616 for ||>, ||>>, |>>,
  4617 
  4618 * Pure/library.ML no longer defines its own option datatype, but uses
  4619 that of the SML basis, which has constructors NONE and SOME instead of
  4620 None and Some, as well as exception Option.Option instead of OPTION.
  4621 The functions the, if_none, is_some, is_none have been adapted
  4622 accordingly, while Option.map replaces apsome.
  4623 
  4624 * Pure/library.ML: the exception LIST has been given up in favour of
  4625 the standard exceptions Empty and Subscript, as well as
  4626 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  4627 superceded by the standard hd and tl functions etc.
  4628 
  4629 A number of basic list functions are no longer exported to the ML
  4630 toplevel, as they are variants of predefined functions.  The following
  4631 suggests how one can translate existing code:
  4632 
  4633     rev_append xs ys = List.revAppend (xs, ys)
  4634     nth_elem (i, xs) = List.nth (xs, i)
  4635     last_elem xs = List.last xs
  4636     flat xss = List.concat xss
  4637     seq fs = List.app fs
  4638     partition P xs = List.partition P xs
  4639     mapfilter f xs = List.mapPartial f xs
  4640 
  4641 * Pure/library.ML: several combinators for linear functional
  4642 transformations, notably reverse application and composition:
  4643 
  4644   x |> f                f #> g
  4645   (x, y) |-> f          f #-> g
  4646 
  4647 * Pure/library.ML: introduced/changed precedence of infix operators:
  4648 
  4649   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  4650   infix 2 ?;
  4651   infix 3 o oo ooo oooo;
  4652   infix 4 ~~ upto downto;
  4653 
  4654 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  4655 infix operators.
  4656 
  4657 * Pure/library.ML: natural list combinators fold, fold_rev, and
  4658 fold_map support linear functional transformations and nesting.  For
  4659 example:
  4660 
  4661   fold f [x1, ..., xN] y =
  4662     y |> f x1 |> ... |> f xN
  4663 
  4664   (fold o fold) f [xs1, ..., xsN] y =
  4665     y |> fold f xs1 |> ... |> fold f xsN
  4666 
  4667   fold f [x1, ..., xN] =
  4668     f x1 #> ... #> f xN
  4669 
  4670   (fold o fold) f [xs1, ..., xsN] =
  4671     fold f xs1 #> ... #> fold f xsN
  4672 
  4673 * Pure/library.ML: the following selectors on type 'a option are
  4674 available:
  4675 
  4676   the:               'a option -> 'a  (*partial*)
  4677   these:             'a option -> 'a  where 'a = 'b list
  4678   the_default: 'a -> 'a option -> 'a
  4679   the_list:          'a option -> 'a list
  4680 
  4681 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  4682 basic operations for association lists, following natural argument
  4683 order; moreover the explicit equality predicate passed here avoids
  4684 potentially expensive polymorphic runtime equality checks.
  4685 The old functions may be expressed as follows:
  4686 
  4687   assoc = uncurry (AList.lookup (op =))
  4688   assocs = these oo AList.lookup (op =)
  4689   overwrite = uncurry (AList.update (op =)) o swap
  4690 
  4691 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  4692 
  4693   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  4694   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  4695 
  4696 replacing make_keylist and keyfilter (occassionally used)
  4697 Naive rewrites:
  4698 
  4699   make_keylist = AList.make
  4700   keyfilter = AList.find (op =)
  4701 
  4702 * eq_fst and eq_snd now take explicit equality parameter, thus
  4703   avoiding eqtypes. Naive rewrites:
  4704 
  4705     eq_fst = eq_fst (op =)
  4706     eq_snd = eq_snd (op =)
  4707 
  4708 * Removed deprecated apl and apr (rarely used).
  4709   Naive rewrites:
  4710 
  4711     apl (n, op) =>>= curry op n
  4712     apr (op, m) =>>= fn n => op (n, m)
  4713 
  4714 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  4715 provides a reasonably efficient light-weight implementation of sets as
  4716 lists.
  4717 
  4718 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  4719 few new operations; existing lookup and update are now curried to
  4720 follow natural argument order (for use with fold etc.);
  4721 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  4722 
  4723 * Pure/General: output via the Isabelle channels of
  4724 writeln/warning/error etc. is now passed through Output.output, with a
  4725 hook for arbitrary transformations depending on the print_mode
  4726 (cf. Output.add_mode -- the first active mode that provides a output
  4727 function wins).  Already formatted output may be embedded into further
  4728 text via Output.raw; the result of Pretty.string_of/str_of and derived
  4729 functions (string_of_term/cterm/thm etc.) is already marked raw to
  4730 accommodate easy composition of diagnostic messages etc.  Programmers
  4731 rarely need to care about Output.output or Output.raw at all, with
  4732 some notable exceptions: Output.output is required when bypassing the
  4733 standard channels (writeln etc.), or in token translations to produce
  4734 properly formatted results; Output.raw is required when capturing
  4735 already output material that will eventually be presented to the user
  4736 a second time.  For the default print mode, both Output.output and
  4737 Output.raw have no effect.
  4738 
  4739 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  4740 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  4741 cumulative results are displayed at the end of a batch session.
  4742 
  4743 * Pure/General: File.sysify_path and File.quote_sysify path have been
  4744 replaced by File.platform_path and File.shell_path (with appropriate
  4745 hooks).  This provides a clean interface for unusual systems where the
  4746 internal and external process view of file names are different.
  4747 
  4748 * Pure: more efficient orders for basic syntactic entities: added
  4749 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  4750 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  4751 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  4752 orders now -- potential INCOMPATIBILITY for code that depends on a
  4753 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  4754 Library.sort_strings on result).
  4755 
  4756 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  4757 fold_types traverse types/terms from left to right, observing natural
  4758 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  4759 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  4760 
  4761 * Pure: name spaces have been refined, with significant changes of the
  4762 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  4763 to extern(_table).  The plain name entry path is superceded by a
  4764 general 'naming' context, which also includes the 'policy' to produce
  4765 a fully qualified name and external accesses of a fully qualified
  4766 name; NameSpace.extend is superceded by context dependent
  4767 Sign.declare_name.  Several theory and proof context operations modify
  4768 the naming context.  Especially note Theory.restore_naming and
  4769 ProofContext.restore_naming to get back to a sane state; note that
  4770 Theory.add_path is no longer sufficient to recover from
  4771 Theory.absolute_path in particular.
  4772 
  4773 * Pure: new flags short_names (default false) and unique_names
  4774 (default true) for controlling output of qualified names.  If
  4775 short_names is set, names are printed unqualified.  If unique_names is
  4776 reset, the name prefix is reduced to the minimum required to achieve
  4777 the original result when interning again, even if there is an overlap
  4778 with earlier declarations.
  4779 
  4780 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  4781 now 'extend', and 'merge' gets an additional Pretty.pp argument
  4782 (useful for printing error messages).  INCOMPATIBILITY.
  4783 
  4784 * Pure: major reorganization of the theory context.  Type Sign.sg and
  4785 Theory.theory are now identified, referring to the universal
  4786 Context.theory (see Pure/context.ML).  Actual signature and theory
  4787 content is managed as theory data.  The old code and interfaces were
  4788 spread over many files and structures; the new arrangement introduces
  4789 considerable INCOMPATIBILITY to gain more clarity:
  4790 
  4791   Context -- theory management operations (name, identity, inclusion,
  4792     parents, ancestors, merge, etc.), plus generic theory data;
  4793 
  4794   Sign -- logical signature and syntax operations (declaring consts,
  4795     types, etc.), plus certify/read for common entities;
  4796 
  4797   Theory -- logical theory operations (stating axioms, definitions,
  4798     oracles), plus a copy of logical signature operations (consts,
  4799     types, etc.); also a few basic management operations (Theory.copy,
  4800     Theory.merge, etc.)
  4801 
  4802 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  4803 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  4804 for convenience -- they merely return the theory.
  4805 
  4806 * Pure: type Type.tsig is superceded by theory in most interfaces.
  4807 
  4808 * Pure: the Isar proof context type is already defined early in Pure
  4809 as Context.proof (note that ProofContext.context and Proof.context are
  4810 aliases, where the latter is the preferred name).  This enables other
  4811 Isabelle components to refer to that type even before Isar is present.
  4812 
  4813 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  4814 typeK, constK, axiomK, oracleK), but provide explicit operations for
  4815 any of these kinds.  For example, Sign.intern typeK is now
  4816 Sign.intern_type, Theory.hide_space Sign.typeK is now
  4817 Theory.hide_types.  Also note that former
  4818 Theory.hide_classes/types/consts are now
  4819 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  4820 internalize their arguments!  INCOMPATIBILITY.
  4821 
  4822 * Pure: get_thm interface (of PureThy and ProofContext) expects
  4823 datatype thmref (with constructors Name and NameSelection) instead of
  4824 plain string -- INCOMPATIBILITY;
  4825 
  4826 * Pure: cases produced by proof methods specify options, where NONE
  4827 means to remove case bindings -- INCOMPATIBILITY in
  4828 (RAW_)METHOD_CASES.
  4829 
  4830 * Pure: the following operations retrieve axioms or theorems from a
  4831 theory node or theory hierarchy, respectively:
  4832 
  4833   Theory.axioms_of: theory -> (string * term) list
  4834   Theory.all_axioms_of: theory -> (string * term) list
  4835   PureThy.thms_of: theory -> (string * thm) list
  4836   PureThy.all_thms_of: theory -> (string * thm) list
  4837 
  4838 * Pure: print_tac now outputs the goal through the trace channel.
  4839 
  4840 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  4841 Reference Toplevel.debug (default false) controls detailed printing
  4842 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  4843 controls execution profiling -- set to 1 for time and 2 for space
  4844 (both increase the runtime).
  4845 
  4846 * Isar session: The initial use of ROOT.ML is now always timed,
  4847 i.e. the log will show the actual process times, in contrast to the
  4848 elapsed wall-clock time that the outer shell wrapper produces.
  4849 
  4850 * Simplifier: improved handling of bound variables (nameless
  4851 representation, avoid allocating new strings).  Simprocs that invoke
  4852 the Simplifier recursively should use Simplifier.inherit_bounds to
  4853 avoid local name clashes.  Failure to do so produces warnings
  4854 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  4855 for further details.
  4856 
  4857 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  4858 bindings for all theorems stored within a given theory; this may help
  4859 in porting non-Isar theories to Isar ones, while keeping ML proof
  4860 scripts for the time being.
  4861 
  4862 * ML operator HTML.with_charset specifies the charset begin used for
  4863 generated HTML files.  For example:
  4864 
  4865   HTML.with_charset "utf-8" use_thy "Hebrew";
  4866   HTML.with_charset "utf-8" use_thy "Chinese";
  4867 
  4868 
  4869 *** System ***
  4870 
  4871 * Allow symlinks to all proper Isabelle executables (Isabelle,
  4872 isabelle, isatool etc.).
  4873 
  4874 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  4875 isatool doc, isatool mkdir, display_drafts etc.).
  4876 
  4877 * isatool usedir: option -f allows specification of the ML file to be
  4878 used by Isabelle; default is ROOT.ML.
  4879 
  4880 * New isatool version outputs the version identifier of the Isabelle
  4881 distribution being used.
  4882 
  4883 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  4884 (containing Boolean satisfiability problems) into Isabelle/HOL
  4885 theories.
  4886 
  4887 
  4888 
  4889 New in Isabelle2004 (April 2004)
  4890 --------------------------------
  4891 
  4892 *** General ***
  4893 
  4894 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  4895   Replaces linorder.ML.
  4896 
  4897 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  4898   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  4899   (\<a>...\<z>), are now considered normal letters, and can therefore
  4900   be used anywhere where an ASCII letter (a...zA...Z) has until
  4901   now. COMPATIBILITY: This obviously changes the parsing of some
  4902   terms, especially where a symbol has been used as a binder, say
  4903   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  4904   as an identifier.  Fix it by inserting a space around former
  4905   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  4906   existing theory and ML files.
  4907 
  4908 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  4909 
  4910 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  4911   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  4912   a normal (but invisible) letter. For multiple letter subscripts repeat
  4913   \<^isub> like this: x\<^isub>1\<^isub>2.
  4914 
  4915 * Pure: There are now sub-/superscripts that can span more than one
  4916   character. Text between \<^bsub> and \<^esub> is set in subscript in
  4917   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  4918   superscript. The new control characters are not identifier parts.
  4919 
  4920 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  4921   content of "..." to the latex file instead of \isacntrl... . The "..."
  4922   may consist of any printable characters excluding the end bracket >.
  4923 
  4924 * Pure: Using new Isar command "finalconsts" (or the ML functions
  4925   Theory.add_finals or Theory.add_finals_i) it is now possible to
  4926   declare constants "final", which prevents their being given a definition
  4927   later.  It is useful for constants whose behaviour is fixed axiomatically
  4928   rather than definitionally, such as the meta-logic connectives.
  4929 
  4930 * Pure: 'instance' now handles general arities with general sorts
  4931   (i.e. intersections of classes),
  4932 
  4933 * Presentation: generated HTML now uses a CSS style sheet to make layout
  4934   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  4935   It can be changed to alter the colors/layout of generated pages.
  4936 
  4937 
  4938 *** Isar ***
  4939 
  4940 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  4941   cut_tac, subgoal_tac and thin_tac:
  4942   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  4943     locales are no longer forced to write Isar proof scripts.
  4944     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  4945     emulations.
  4946   - INCOMPATIBILITY: names of variables to be instantiated may no
  4947     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  4948     This is consistent with the instantiation attribute "where".
  4949 
  4950 * Attributes "where" and "of":
  4951   - Now take type variables of instantiated theorem into account when reading
  4952     the instantiation string.  This fixes a bug that caused instantiated
  4953     theorems to have too special types in some circumstances.
  4954   - "where" permits explicit instantiations of type variables.
  4955 
  4956 * Calculation commands "moreover" and "also" no longer interfere with
  4957   current facts ("this"), admitting arbitrary combinations with "then"
  4958   and derived forms.
  4959 
  4960 * Locales:
  4961   - Goal statements involving the context element "includes" no longer
  4962     generate theorems with internal delta predicates (those ending on
  4963     "_axioms") in the premise.
  4964     Resolve particular premise with <locale>.intro to obtain old form.
  4965   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  4966     specification and "includes" elements in goal statement.
  4967   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  4968     [intro?] and [elim?] (respectively) by default.
  4969   - Experimental command for instantiation of locales in proof contexts:
  4970         instantiate <label>[<attrs>]: <loc>
  4971     Instantiates locale <loc> and adds all its theorems to the current context
  4972     taking into account their attributes.  Label and attrs are optional
  4973     modifiers, like in theorem declarations.  If present, names of
  4974     instantiated theorems are qualified with <label>, and the attributes
  4975     <attrs> are applied after any attributes these theorems might have already.
  4976       If the locale has assumptions, a chained fact of the form
  4977     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  4978     are derived.  The command does not support old-style locales declared
  4979     with "locale (open)".
  4980       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  4981 
  4982 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  4983   (Isar) contexts.
  4984 
  4985 
  4986 *** HOL ***
  4987 
  4988 * Proof import: new image HOL4 contains the imported library from
  4989   the HOL4 system with about 2500 theorems. It is imported by
  4990   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  4991   can be used like any other Isabelle image.  See
  4992   HOL/Import/HOL/README for more information.
  4993 
  4994 * Simplifier:
  4995   - Much improved handling of linear and partial orders.
  4996     Reasoners for linear and partial orders are set up for type classes
  4997     "linorder" and "order" respectively, and are added to the default simpset
  4998     as solvers.  This means that the simplifier can build transitivity chains
  4999     to solve goals from the assumptions.
  5000   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5001     of blast or auto after simplification become unnecessary because the goal
  5002     is solved by simplification already.
  5003 
  5004 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5005     all proved in axiomatic type classes for semirings, rings and fields.
  5006 
  5007 * Numerics:
  5008   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5009     now formalized using the Ring_and_Field theory mentioned above.
  5010   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5011     than before, because now they are set up once in a generic manner.
  5012   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5013     Look for the general versions in Ring_and_Field (and Power if they concern
  5014     exponentiation).
  5015 
  5016 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5017 
  5018 * Records:
  5019   - Record types are now by default printed with their type abbreviation
  5020     instead of the list of all field types. This can be configured via
  5021     the reference "print_record_type_abbr".
  5022   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5023     (not enabled by default).
  5024   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5025     EX x. x = sel r to True (not enabled by default).
  5026   - Tactic "record_split_simp_tac" to split and simplify records added.
  5027 
  5028 * 'specification' command added, allowing for definition by
  5029   specification.  There is also an 'ax_specification' command that
  5030   introduces the new constants axiomatically.
  5031 
  5032 * arith(_tac) is now able to generate counterexamples for reals as well.
  5033 
  5034 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5035 
  5036 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5037   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5038 
  5039 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5040   matrix theory to linear programming.
  5041 
  5042 * Unions and Intersections:
  5043   The latex output syntax of UN and INT has been changed
  5044   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5045   i.e. the index formulae has become a subscript.
  5046   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5047 
  5048 * Unions and Intersections over Intervals:
  5049   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5050   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5051   like in normal math, and corresponding versions for < and for intersection.
  5052 
  5053 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5054   lexicographic dictonary ordering has been added as "lexord".
  5055 
  5056 * ML: the legacy theory structures Int and List have been removed. They had
  5057   conflicted with ML Basis Library structures having the same names.
  5058 
  5059 * 'refute' command added to search for (finite) countermodels.  Only works
  5060   for a fragment of HOL.  The installation of an external SAT solver is
  5061   highly recommended.  See "HOL/Refute.thy" for details.
  5062 
  5063 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5064   formulae under an assignment of free variables to random values.
  5065   In contrast to 'refute', it can deal with inductive datatypes,
  5066   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5067   for examples.
  5068 
  5069 
  5070 *** HOLCF ***
  5071 
  5072 * Streams now come with concatenation and are part of the HOLCF image
  5073 
  5074 
  5075 
  5076 New in Isabelle2003 (May 2003)
  5077 ------------------------------
  5078 
  5079 *** General ***
  5080 
  5081 * Provers/simplifier:
  5082 
  5083   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5084     Assumptions are now subject to complete mutual simplification,
  5085     not just from left to right. The simplifier now preserves
  5086     the order of assumptions.
  5087 
  5088     Potential INCOMPATIBILITY:
  5089 
  5090     -- simp sometimes diverges where the old version did
  5091        not, e.g. invoking simp on the goal
  5092 
  5093         [| P (f x); y = x; f x = f y |] ==> Q
  5094 
  5095        now gives rise to the infinite reduction sequence
  5096 
  5097         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5098 
  5099        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5100        kind of problem.
  5101 
  5102     -- Tactics combining classical reasoner and simplification (such as auto)
  5103        are also affected by this change, because many of them rely on
  5104        simp. They may sometimes diverge as well or yield a different numbers
  5105        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5106        in case of problems. Sometimes subsequent calls to the classical
  5107        reasoner will fail because a preceeding call to the simplifier too
  5108        eagerly simplified the goal, e.g. deleted redundant premises.
  5109 
  5110   - The simplifier trace now shows the names of the applied rewrite rules
  5111 
  5112   - You can limit the number of recursive invocations of the simplifier
  5113     during conditional rewriting (where the simplifie tries to solve the
  5114     conditions before applying the rewrite rule):
  5115     ML "simp_depth_limit := n"
  5116     where n is an integer. Thus you can force termination where previously
  5117     the simplifier would diverge.
  5118 
  5119   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5120 
  5121   - No longer aborts on failed congruence proof.  Instead, the
  5122     congruence is ignored.
  5123 
  5124 * Pure: New generic framework for extracting programs from constructive
  5125   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5126   as HOL/Extraction for some case studies.
  5127 
  5128 * Pure: The main goal of the proof state is no longer shown by default, only
  5129 the subgoals. This behaviour is controlled by a new flag.
  5130    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5131 (ML: Proof.show_main_goal).
  5132 
  5133 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5134 rules whose conclusion matches subgoal 1:
  5135       PG menu: Isabelle/Isar -> Show me -> matching rules
  5136 The rules are ordered by how closely they match the subgoal.
  5137 In particular, rules that solve a subgoal outright are displayed first
  5138 (or rather last, the way they are printed).
  5139 (ML: ProofGeneral.print_intros())
  5140 
  5141 * Pure: New flag trace_unify_fail causes unification to print
  5142 diagnostic information (PG: in trace buffer) when it fails. This is
  5143 useful for figuring out why single step proofs like rule, erule or
  5144 assumption failed.
  5145 
  5146 * Pure: Locale specifications now produce predicate definitions
  5147 according to the body of text (covering assumptions modulo local
  5148 definitions); predicate "loc_axioms" covers newly introduced text,
  5149 while "loc" is cumulative wrt. all included locale expressions; the
  5150 latter view is presented only on export into the global theory
  5151 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5152 on the old view without predicates;
  5153 
  5154 * Pure: predefined locales "var" and "struct" are useful for sharing
  5155 parameters (as in CASL, for example); just specify something like
  5156 ``var x + var y + struct M'' as import;
  5157 
  5158 * Pure: improved thms_containing: proper indexing of facts instead of
  5159 raw theorems; check validity of results wrt. current name space;
  5160 include local facts of proof configuration (also covers active
  5161 locales), cover fixed variables in index; may use "_" in term
  5162 specification; an optional limit for the number of printed facts may
  5163 be given (the default is 40);
  5164 
  5165 * Pure: disallow duplicate fact bindings within new-style theory files
  5166 (batch-mode only);
  5167 
  5168 * Provers: improved induct method: assumptions introduced by case
  5169 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5170 the goal statement); "foo" still refers to all facts collectively;
  5171 
  5172 * Provers: the function blast.overloaded has been removed: all constants
  5173 are regarded as potentially overloaded, which improves robustness in exchange
  5174 for slight decrease in efficiency;
  5175 
  5176 * Provers/linorder: New generic prover for transitivity reasoning over
  5177 linear orders.  Note: this prover is not efficient!
  5178 
  5179 * Isar: preview of problems to finish 'show' now produce an error
  5180 rather than just a warning (in interactive mode);
  5181 
  5182 
  5183 *** HOL ***
  5184 
  5185 * arith(_tac)
  5186 
  5187  - Produces a counter example if it cannot prove a goal.
  5188    Note that the counter example may be spurious if the goal is not a formula
  5189    of quantifier-free linear arithmetic.
  5190    In ProofGeneral the counter example appears in the trace buffer.
  5191 
  5192  - Knows about div k and mod k where k is a numeral of type nat or int.
  5193 
  5194  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5195    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5196    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5197 
  5198 * simp's arithmetic capabilities have been enhanced a bit: it now
  5199 takes ~= in premises into account (by performing a case split);
  5200 
  5201 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5202 are distributed over a sum of terms;
  5203 
  5204 * New tactic "trans_tac" and method "trans" instantiate
  5205 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5206 "<=", "<" and "=").
  5207 
  5208 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5209 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5210 
  5211 * 'typedef' command has new option "open" to suppress the set
  5212 definition;
  5213 
  5214 * functions Min and Max on finite sets have been introduced (theory
  5215 Finite_Set);
  5216 
  5217 * attribute [symmetric] now works for relations as well; it turns
  5218 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5219 
  5220 * induct over a !!-quantified statement (say !!x1..xn):
  5221   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5222 
  5223 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5224 %x. None. Warning: empty_def now refers to the previously hidden definition
  5225 of the empty set.
  5226 
  5227 * Algebra: formalization of classical algebra.  Intended as base for
  5228 any algebraic development in Isabelle.  Currently covers group theory
  5229 (up to Sylow's theorem) and ring theory (Universal Property of
  5230 Univariate Polynomials).  Contributions welcome;
  5231 
  5232 * GroupTheory: deleted, since its material has been moved to Algebra;
  5233 
  5234 * Complex: new directory of the complex numbers with numeric constants,
  5235 nonstandard complex numbers, and some complex analysis, standard and
  5236 nonstandard (Jacques Fleuriot);
  5237 
  5238 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  5239 
  5240 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  5241 Fleuriot);
  5242 
  5243 * Real/HahnBanach: updated and adapted to locales;
  5244 
  5245 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  5246 Gray and Kramer);
  5247 
  5248 * UNITY: added the Meier-Sanders theory of progress sets;
  5249 
  5250 * MicroJava: bytecode verifier and lightweight bytecode verifier
  5251 as abstract algorithms, instantiated to the JVM;
  5252 
  5253 * Bali: Java source language formalization. Type system, operational
  5254 semantics, axiomatic semantics. Supported language features:
  5255 classes, interfaces, objects,virtual methods, static methods,
  5256 static/instance fields, arrays, access modifiers, definite
  5257 assignment, exceptions.
  5258 
  5259 
  5260 *** ZF ***
  5261 
  5262 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  5263 universe, etc.);
  5264 
  5265 * Main ZF: virtually all theories converted to new-style format;
  5266 
  5267 
  5268 *** ML ***
  5269 
  5270 * Pure: Tactic.prove provides sane interface for internal proofs;
  5271 omits the infamous "standard" operation, so this is more appropriate
  5272 than prove_goalw_cterm in many situations (e.g. in simprocs);
  5273 
  5274 * Pure: improved error reporting of simprocs;
  5275 
  5276 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  5277 up simprocs;
  5278 
  5279 
  5280 *** Document preparation ***
  5281 
  5282 * uses \par instead of \\ for line breaks in theory text. This may
  5283 shift some page breaks in large documents. To get the old behaviour
  5284 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  5285 
  5286 * minimized dependencies of isabelle.sty and isabellesym.sty on
  5287 other packages
  5288 
  5289 * \<euro> now needs package babel/greek instead of marvosym (which
  5290 broke \Rightarrow)
  5291 
  5292 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  5293 textcomp package)
  5294 
  5295 
  5296 
  5297 New in Isabelle2002 (March 2002)
  5298 --------------------------------
  5299 
  5300 *** Document preparation ***
  5301 
  5302 * greatly simplified document preparation setup, including more
  5303 graceful interpretation of isatool usedir -i/-d/-D options, and more
  5304 instructive isatool mkdir; users should basically be able to get
  5305 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  5306 users may run a separate document processing stage manually like this:
  5307 "isatool usedir -D output HOL Test && isatool document Test/output";
  5308 
  5309 * theory dependency graph may now be incorporated into documents;
  5310 isatool usedir -g true will produce session_graph.eps/.pdf for use
  5311 with \includegraphics of LaTeX;
  5312 
  5313 * proper spacing of consecutive markup elements, especially text
  5314 blocks after section headings;
  5315 
  5316 * support bold style (for single symbols only), input syntax is like
  5317 this: "\<^bold>\<alpha>" or "\<^bold>A";
  5318 
  5319 * \<bullet> is now output as bold \cdot by default, which looks much
  5320 better in printed text;
  5321 
  5322 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  5323 note that these symbols are currently unavailable in Proof General /
  5324 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  5325 
  5326 * isatool latex no longer depends on changed TEXINPUTS, instead
  5327 isatool document copies the Isabelle style files to the target
  5328 location;
  5329 
  5330 
  5331 *** Isar ***
  5332 
  5333 * Pure/Provers: improved proof by cases and induction;
  5334   - 'case' command admits impromptu naming of parameters (such as
  5335     "case (Suc n)");
  5336   - 'induct' method divinates rule instantiation from the inductive
  5337     claim; no longer requires excessive ?P bindings for proper
  5338     instantiation of cases;
  5339   - 'induct' method properly enumerates all possibilities of set/type
  5340     rules; as a consequence facts may be also passed through *type*
  5341     rules without further ado;
  5342   - 'induct' method now derives symbolic cases from the *rulified*
  5343     rule (before it used to rulify cases stemming from the internal
  5344     atomized version); this means that the context of a non-atomic
  5345     statement becomes is included in the hypothesis, avoiding the
  5346     slightly cumbersome show "PROP ?case" form;
  5347   - 'induct' may now use elim-style induction rules without chaining
  5348     facts, using ``missing'' premises from the goal state; this allows
  5349     rules stemming from inductive sets to be applied in unstructured
  5350     scripts, while still benefitting from proper handling of non-atomic
  5351     statements; NB: major inductive premises need to be put first, all
  5352     the rest of the goal is passed through the induction;
  5353   - 'induct' proper support for mutual induction involving non-atomic
  5354     rule statements (uses the new concept of simultaneous goals, see
  5355     below);
  5356   - append all possible rule selections, but only use the first
  5357     success (no backtracking);
  5358   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  5359   - undeclared rule case names default to numbers 1, 2, 3, ...;
  5360   - added 'print_induct_rules' (covered by help item in recent Proof
  5361     General versions);
  5362   - moved induct/cases attributes to Pure, methods to Provers;
  5363   - generic method setup instantiated for FOL and HOL;
  5364 
  5365 * Pure: support multiple simultaneous goal statements, for example
  5366 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  5367 meta-level mechanism, this acts as if several individual goals had
  5368 been stated separately; in particular common proof methods need to be
  5369 repeated in order to cover all claims; note that a single elimination
  5370 step is *not* sufficient to establish the two conjunctions, so this
  5371 fails:
  5372 
  5373   assume "A & B" then have A and B ..   (*".." fails*)
  5374 
  5375 better use "obtain" in situations as above; alternative refer to
  5376 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  5377 
  5378 * Pure: proper integration with ``locales''; unlike the original
  5379 version by Florian Kammller, Isar locales package high-level proof
  5380 contexts rather than raw logical ones (e.g. we admit to include
  5381 attributes everywhere); operations on locales include merge and
  5382 rename; support for implicit arguments (``structures''); simultaneous
  5383 type-inference over imports and text; see also HOL/ex/Locales.thy for
  5384 some examples;
  5385 
  5386 * Pure: the following commands have been ``localized'', supporting a
  5387 target locale specification "(in name)": 'lemma', 'theorem',
  5388 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  5389 stored both within the locale and at the theory level (exported and
  5390 qualified by the locale name);
  5391 
  5392 * Pure: theory goals may now be specified in ``long'' form, with
  5393 ad-hoc contexts consisting of arbitrary locale elements. for example
  5394 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  5395 definitions may be given, too); the result is a meta-level rule with
  5396 the context elements being discharged in the obvious way;
  5397 
  5398 * Pure: new proof command 'using' allows to augment currently used
  5399 facts after a goal statement ('using' is syntactically analogous to
  5400 'apply', but acts on the goal's facts only); this allows chained facts
  5401 to be separated into parts given before and after a claim, as in
  5402 ``from a and b have C using d and e <proof>'';
  5403 
  5404 * Pure: renamed "antecedent" case to "rule_context";
  5405 
  5406 * Pure: new 'judgment' command records explicit information about the
  5407 object-logic embedding (used by several tools internally); no longer
  5408 use hard-wired "Trueprop";
  5409 
  5410 * Pure: added 'corollary' command;
  5411 
  5412 * Pure: fixed 'token_translation' command;
  5413 
  5414 * Pure: removed obsolete 'exported' attribute;
  5415 
  5416 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  5417 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  5418 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  5419 
  5420 * Pure: method 'atomize' presents local goal premises as object-level
  5421 statements (atomic meta-level propositions); setup controlled via
  5422 rewrite rules declarations of 'atomize' attribute; example
  5423 application: 'induct' method with proper rule statements in improper
  5424 proof *scripts*;
  5425 
  5426 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  5427 now consider the syntactic context of assumptions, giving a better
  5428 chance to get type-inference of the arguments right (this is
  5429 especially important for locales);
  5430 
  5431 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  5432 mode;
  5433 
  5434 * Pure/obtain: the formal conclusion "thesis", being marked as
  5435 ``internal'', may no longer be reference directly in the text;
  5436 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  5437 situations;
  5438 
  5439 * Pure: generic 'sym' attribute which declares a rule both as pure
  5440 'elim?' and for the 'symmetric' operation;
  5441 
  5442 * Pure: marginal comments ``--'' may now occur just anywhere in the
  5443 text; the fixed correlation with particular command syntax has been
  5444 discontinued;
  5445 
  5446 * Pure: new method 'rules' is particularly well-suited for proof
  5447 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  5448 but often produces more compact proof terms with less detours;
  5449 
  5450 * Pure/Provers/classical: simplified integration with pure rule
  5451 attributes and methods; the classical "intro?/elim?/dest?"
  5452 declarations coincide with the pure ones; the "rule" method no longer
  5453 includes classically swapped intros; "intro" and "elim" methods no
  5454 longer pick rules from the context; also got rid of ML declarations
  5455 AddXIs/AddXEs/AddXDs; all of this has some potential for
  5456 INCOMPATIBILITY;
  5457 
  5458 * Provers/classical: attribute 'swapped' produces classical inversions
  5459 of introduction rules;
  5460 
  5461 * Provers/simplifier: 'simplified' attribute may refer to explicit
  5462 rules instead of full simplifier context; 'iff' attribute handles
  5463 conditional rules;
  5464 
  5465 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  5466 
  5467 * HOL: 'recdef' now fails on unfinished automated proofs, use
  5468 "(permissive)" option to recover old behavior;
  5469 
  5470 * HOL: 'inductive' no longer features separate (collective) attributes
  5471 for 'intros' (was found too confusing);
  5472 
  5473 * HOL: properly declared induction rules less_induct and
  5474 wf_induct_rule;
  5475 
  5476 
  5477 *** HOL ***
  5478 
  5479 * HOL: moved over to sane numeral syntax; the new policy is as
  5480 follows:
  5481 
  5482   - 0 and 1 are polymorphic constants, which are defined on any
  5483   numeric type (nat, int, real etc.);
  5484 
  5485   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  5486   binary representation internally;
  5487 
  5488   - type nat has special constructor Suc, and generally prefers Suc 0
  5489   over 1::nat and Suc (Suc 0) over 2::nat;
  5490 
  5491 This change may cause significant problems of INCOMPATIBILITY; here
  5492 are some hints on converting existing sources:
  5493 
  5494   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  5495   entities, so expressions involving "-" (unary or binary minus) need
  5496   to be spaced properly;
  5497 
  5498   - existing occurrences of "1" may need to be constraint "1::nat" or
  5499   even replaced by Suc 0; similar for old "2";
  5500 
  5501   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  5502 
  5503   - remove all special provisions on numerals in proofs;
  5504 
  5505 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  5506 representation (depends on bin_arith_simps in the default context);
  5507 
  5508 * HOL: symbolic syntax for x^2 (numeral 2);
  5509 
  5510 * HOL: the class of all HOL types is now called "type" rather than
  5511 "term"; INCOMPATIBILITY, need to adapt references to this type class
  5512 in axclass/classes, instance/arities, and (usually rare) occurrences
  5513 in typings (of consts etc.); internally the class is called
  5514 "HOL.type", ML programs should refer to HOLogic.typeS;
  5515 
  5516 * HOL/record package improvements:
  5517   - new derived operations "fields" to build a partial record section,
  5518     "extend" to promote a fixed record to a record scheme, and
  5519     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  5520     declared as simp by default;
  5521   - shared operations ("more", "fields", etc.) now need to be always
  5522     qualified) --- potential INCOMPATIBILITY;
  5523   - removed "make_scheme" operations (use "make" with "extend") --
  5524     INCOMPATIBILITY;
  5525   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  5526   - provides cases/induct rules for use with corresponding Isar
  5527     methods (for concrete records, record schemes, concrete more
  5528     parts, and schematic more parts -- in that order);
  5529   - internal definitions directly based on a light-weight abstract
  5530     theory of product types over typedef rather than datatype;
  5531 
  5532 * HOL: generic code generator for generating executable ML code from
  5533 specifications; specific support for HOL constructs such as inductive
  5534 datatypes and sets, as well as recursive functions; can be invoked
  5535 via 'generate_code' theory section;
  5536 
  5537 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  5538 
  5539 * HOL: consolidated and renamed several theories.  In particular:
  5540         Ord.thy has been absorbed into HOL.thy
  5541         String.thy has been absorbed into List.thy
  5542 
  5543 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  5544 (beware of argument permutation!);
  5545 
  5546 * HOL: linorder_less_split superseded by linorder_cases;
  5547 
  5548 * HOL/List: "nodups" renamed to "distinct";
  5549 
  5550 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  5551 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  5552   - Ex_def has changed, now need to use some_eq_ex
  5553 
  5554 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  5555 in this (rare) case use:
  5556 
  5557   delSWrapper "split_all_tac"
  5558   addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
  5559 
  5560 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
  5561 MAY FAIL;
  5562 
  5563 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
  5564 Isabelle's type classes, ^ on functions and relations has too general
  5565 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be
  5566 necessary to attach explicit type constraints;
  5567 
  5568 * HOL/Relation: the prefix name of the infix "O" has been changed from
  5569 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been
  5570 renamed accordingly (eg "compI" -> "rel_compI").
  5571 
  5572 * HOL: syntax translations now work properly with numerals and records
  5573 expressions;
  5574 
  5575 * HOL: bounded abstraction now uses syntax "%" / "\<lambda>" instead
  5576 of "lam" -- INCOMPATIBILITY;
  5577 
  5578 * HOL: got rid of some global declarations (potential INCOMPATIBILITY
  5579 for ML tools): const "()" renamed "Product_Type.Unity", type "unit"
  5580 renamed "Product_Type.unit";
  5581 
  5582 * HOL: renamed rtrancl_into_rtrancl2 to converse_rtrancl_into_rtrancl
  5583 
  5584 * HOL: removed obsolete theorem "optionE" (use "option.exhaust", or
  5585 the "cases" method);
  5586 
  5587 * HOL/GroupTheory: group theory examples including Sylow's theorem (by
  5588 Florian Kammller);
  5589 
  5590 * HOL/IMP: updated and converted to new-style theory format; several
  5591 parts turned into readable document, with proper Isar proof texts and
  5592 some explanations (by Gerwin Klein);
  5593 
  5594 * HOL-Real: added Complex_Numbers (by Gertrud Bauer);
  5595 
  5596 * HOL-Hyperreal is now a logic image;
  5597 
  5598 
  5599 *** HOLCF ***
  5600 
  5601 * Isar: consts/constdefs supports mixfix syntax for continuous
  5602 operations;
  5603 
  5604 * Isar: domain package adapted to new-style theory format, e.g. see
  5605 HOLCF/ex/Dnat.thy;
  5606 
  5607 * theory Lift: proper use of rep_datatype lift instead of ML hacks --
  5608 potential INCOMPATIBILITY; now use plain induct_tac instead of former
  5609 lift.induct_tac, always use UU instead of Undef;
  5610 
  5611 * HOLCF/IMP: updated and converted to new-style theory;
  5612 
  5613 
  5614 *** ZF ***
  5615 
  5616 * Isar: proper integration of logic-specific tools and packages,
  5617 including theory commands '(co)inductive', '(co)datatype',
  5618 'rep_datatype', 'inductive_cases', as well as methods 'ind_cases',
  5619 'induct_tac', 'case_tac', and 'typecheck' (with attribute 'TC');
  5620 
  5621 * theory Main no longer includes AC; for the Axiom of Choice, base
  5622 your theory on Main_ZFC;
  5623 
  5624 * the integer library now covers quotients and remainders, with many
  5625 laws relating division to addition, multiplication, etc.;
  5626 
  5627 * ZF/UNITY: Chandy and Misra's UNITY is now available in ZF, giving a
  5628 typeless version of the formalism;
  5629 
  5630 * ZF/AC, Coind, IMP, Resid: updated and converted to new-style theory
  5631 format;
  5632 
  5633 * ZF/Induct: new directory for examples of inductive definitions,
  5634 including theory Multiset for multiset orderings; converted to
  5635 new-style theory format;
  5636 
  5637 * ZF: many new theorems about lists, ordinals, etc.;
  5638 
  5639 
  5640 *** General ***
  5641 
  5642 * Pure/kernel: meta-level proof terms (by Stefan Berghofer); reference
  5643 variable proof controls level of detail: 0 = no proofs (only oracle
  5644 dependencies), 1 = lemma dependencies, 2 = compact proof terms; see
  5645 also ref manual for further ML interfaces;
  5646 
  5647 * Pure/axclass: removed obsolete ML interface
  5648 goal_subclass/goal_arity;
  5649 
  5650 * Pure/syntax: new token syntax "num" for plain numerals (without "#"
  5651 of "xnum"); potential INCOMPATIBILITY, since -0, -1 etc. are now
  5652 separate tokens, so expressions involving minus need to be spaced
  5653 properly;
  5654 
  5655 * Pure/syntax: support non-oriented infixes, using keyword "infix"
  5656 rather than "infixl" or "infixr";
  5657 
  5658 * Pure/syntax: concrete syntax for dummy type variables admits genuine
  5659 sort constraint specifications in type inference; e.g. "x::_::foo"
  5660 ensures that the type of "x" is of sort "foo" (but not necessarily a
  5661 type variable);
  5662 
  5663 * Pure/syntax: print modes "type_brackets" and "no_type_brackets"
  5664 control output of nested => (types); the default behavior is
  5665 "type_brackets";
  5666 
  5667 * Pure/syntax: builtin parse translation for "_constify" turns valued
  5668 tokens into AST constants;
  5669 
  5670 * Pure/syntax: prefer later declarations of translations and print
  5671 translation functions; potential INCOMPATIBILITY: need to reverse
  5672 multiple declarations for same syntax element constant;
  5673 
  5674 * Pure/show_hyps reset by default (in accordance to existing Isar
  5675 practice);
  5676 
  5677 * Provers/classical: renamed addaltern to addafter, addSaltern to
  5678 addSafter;
  5679 
  5680 * Provers/clasimp: ``iff'' declarations now handle conditional rules
  5681 as well;
  5682 
  5683 * system: tested support for MacOS X; should be able to get Isabelle +
  5684 Proof General to work in a plain Terminal after installing Poly/ML
  5685 (e.g. from the Isabelle distribution area) and GNU bash alone
  5686 (e.g. from http://www.apple.com); full X11, XEmacs and X-Symbol
  5687 support requires further installations, e.g. from
  5688 http://fink.sourceforge.net/);
  5689 
  5690 * system: support Poly/ML 4.1.1 (able to manage larger heaps);
  5691 
  5692 * system: reduced base memory usage by Poly/ML (approx. 20 MB instead
  5693 of 40 MB), cf. ML_OPTIONS;
  5694 
  5695 * system: Proof General keywords specification is now part of the
  5696 Isabelle distribution (see etc/isar-keywords.el);
  5697 
  5698 * system: support for persistent Proof General sessions (refrain from
  5699 outdating all loaded theories on startup); user may create writable
  5700 logic images like this: ``isabelle -q HOL Test'';
  5701 
  5702 * system: smart selection of Isabelle process versus Isabelle
  5703 interface, accommodates case-insensitive file systems (e.g. HFS+); may
  5704 run both "isabelle" and "Isabelle" even if file names are badly
  5705 damaged (executable inspects the case of the first letter of its own
  5706 name); added separate "isabelle-process" and "isabelle-interface";
  5707 
  5708 * system: refrain from any attempt at filtering input streams; no
  5709 longer support ``8bit'' encoding of old isabelle font, instead proper
  5710 iso-latin characters may now be used; the related isatools
  5711 "symbolinput" and "nonascii" have disappeared as well;
  5712 
  5713 * system: removed old "xterm" interface (the print modes "xterm" and
  5714 "xterm_color" are still available for direct use in a suitable
  5715 terminal);
  5716 
  5717 
  5718 
  5719 New in Isabelle99-2 (February 2001)
  5720 -----------------------------------
  5721 
  5722 *** Overview of INCOMPATIBILITIES ***
  5723 
  5724 * HOL: please note that theories in the Library and elsewhere often use the
  5725 new-style (Isar) format; to refer to their theorems in an ML script you must
  5726 bind them to ML identifers by e.g.      val thm_name = thm "thm_name";
  5727 
  5728 * HOL: inductive package no longer splits induction rule aggressively,
  5729 but only as far as specified by the introductions given; the old
  5730 format may be recovered via ML function complete_split_rule or attribute
  5731 'split_rule (complete)';
  5732 
  5733 * HOL: induct renamed to lfp_induct, lfp_Tarski to lfp_unfold,
  5734 gfp_Tarski to gfp_unfold;
  5735 
  5736 * HOL: contrapos, contrapos2 renamed to contrapos_nn, contrapos_pp;
  5737 
  5738 * HOL: infix "dvd" now has priority 50 rather than 70 (because it is a
  5739 relation); infix "^^" has been renamed "``"; infix "``" has been
  5740 renamed "`"; "univalent" has been renamed "single_valued";
  5741 
  5742 * HOL/Real: "rinv" and "hrinv" replaced by overloaded "inverse"
  5743 operation;
  5744 
  5745 * HOLCF: infix "`" has been renamed "$"; the symbol syntax is \<cdot>;
  5746 
  5747 * Isar: 'obtain' no longer declares "that" fact as simp/intro;
  5748 
  5749 * Isar/HOL: method 'induct' now handles non-atomic goals; as a
  5750 consequence, it is no longer monotonic wrt. the local goal context
  5751 (which is now passed through the inductive cases);
  5752 
  5753 * Document preparation: renamed standard symbols \<ll> to \<lless> and
  5754 \<gg> to \<ggreater>;
  5755 
  5756 
  5757 *** Document preparation ***
  5758 
  5759 * \isabellestyle{NAME} selects version of Isabelle output (currently
  5760 available: are "it" for near math-mode best-style output, "sl" for
  5761 slanted text style, and "tt" for plain type-writer; if no
  5762 \isabellestyle command is given, output is according to slanted
  5763 type-writer);
  5764 
  5765 * support sub/super scripts (for single symbols only), input syntax is
  5766 like this: "A\<^sup>*" or "A\<^sup>\<star>";
  5767 
  5768 * some more standard symbols; see Appendix A of the system manual for
  5769 the complete list of symbols defined in isabellesym.sty;
  5770 
  5771 * improved isabelle style files; more abstract symbol implementation
  5772 (should now use \isamath{...} and \isatext{...} in custom symbol
  5773 definitions);
  5774 
  5775 * antiquotation @{goals} and @{subgoals} for output of *dynamic* goals
  5776 state; Note that presentation of goal states does not conform to
  5777 actual human-readable proof documents.  Please do not include goal
  5778 states into document output unless you really know what you are doing!
  5779 
  5780 * proper indentation of antiquoted output with proportional LaTeX
  5781 fonts;
  5782 
  5783 * no_document ML operator temporarily disables LaTeX document
  5784 generation;
  5785 
  5786 * isatool unsymbolize tunes sources for plain ASCII communication;
  5787 
  5788 
  5789 *** Isar ***
  5790 
  5791 * Pure: Isar now suffers initial goal statements to contain unbound
  5792 schematic variables (this does not conform to actual readable proof
  5793 documents, due to unpredictable outcome and non-compositional proof
  5794 checking); users who know what they are doing may use schematic goals
  5795 for Prolog-style synthesis of proven results;
  5796 
  5797 * Pure: assumption method (an implicit finishing) now handles actual
  5798 rules as well;
  5799 
  5800 * Pure: improved 'obtain' --- moved to Pure, insert "that" into
  5801 initial goal, declare "that" only as Pure intro (only for single
  5802 steps); the "that" rule assumption may now be involved in implicit
  5803 finishing, thus ".." becomes a feasible for trivial obtains;
  5804 
  5805 * Pure: default proof step now includes 'intro_classes'; thus trivial
  5806 instance proofs may be performed by "..";
  5807 
  5808 * Pure: ?thesis / ?this / "..." now work for pure meta-level
  5809 statements as well;
  5810 
  5811 * Pure: more robust selection of calculational rules;
  5812 
  5813 * Pure: the builtin notion of 'finished' goal now includes the ==-refl
  5814 rule (as well as the assumption rule);
  5815 
  5816 * Pure: 'thm_deps' command visualizes dependencies of theorems and
  5817 lemmas, using the graph browser tool;
  5818 
  5819 * Pure: predict failure of "show" in interactive mode;
  5820 
  5821 * Pure: 'thms_containing' now takes actual terms as arguments;
  5822 
  5823 * HOL: improved method 'induct' --- now handles non-atomic goals
  5824 (potential INCOMPATIBILITY); tuned error handling;
  5825 
  5826 * HOL: cases and induct rules now provide explicit hints about the
  5827 number of facts to be consumed (0 for "type" and 1 for "set" rules);
  5828 any remaining facts are inserted into the goal verbatim;
  5829 
  5830 * HOL: local contexts (aka cases) may now contain term bindings as
  5831 well; the 'cases' and 'induct' methods new provide a ?case binding for
  5832 the result to be shown in each case;
  5833 
  5834 * HOL: added 'recdef_tc' command;
  5835 
  5836 * isatool convert assists in eliminating legacy ML scripts;
  5837 
  5838 
  5839 *** HOL ***
  5840 
  5841 * HOL/Library: a collection of generic theories to be used together
  5842 with main HOL; the theory loader path already includes this directory
  5843 by default; the following existing theories have been moved here:
  5844 HOL/Induct/Multiset, HOL/Induct/Acc (as Accessible_Part), HOL/While
  5845 (as While_Combinator), HOL/Lex/Prefix (as List_Prefix);
  5846 
  5847 * HOL/Unix: "Some aspects of Unix file-system security", a typical
  5848 modelling and verification task performed in Isabelle/HOL +
  5849 Isabelle/Isar + Isabelle document preparation (by Markus Wenzel).
  5850 
  5851 * HOL/Algebra: special summation operator SUM no longer exists, it has
  5852 been replaced by setsum; infix 'assoc' now has priority 50 (like
  5853 'dvd'); axiom 'one_not_zero' has been moved from axclass 'ring' to
  5854 'domain', this makes the theory consistent with mathematical
  5855 literature;
  5856 
  5857 * HOL basics: added overloaded operations "inverse" and "divide"
  5858 (infix "/"), syntax for generic "abs" operation, generic summation
  5859 operator \<Sum>;
  5860 
  5861 * HOL/typedef: simplified package, provide more useful rules (see also
  5862 HOL/subset.thy);
  5863 
  5864 * HOL/datatype: induction rule for arbitrarily branching datatypes is
  5865 now expressed as a proper nested rule (old-style tactic scripts may
  5866 require atomize_strip_tac to cope with non-atomic premises);
  5867 
  5868 * HOL: renamed theory "Prod" to "Product_Type", renamed "split" rule
  5869 to "split_conv" (old name still available for compatibility);
  5870 
  5871 * HOL: improved concrete syntax for strings (e.g. allows translation
  5872 rules with string literals);
  5873 
  5874 * HOL-Real-Hyperreal: this extends HOL-Real with the hyperreals
  5875  and Fleuriot's mechanization of analysis, including the transcendental
  5876  functions for the reals;
  5877 
  5878 * HOL/Real, HOL/Hyperreal: improved arithmetic simplification;
  5879 
  5880 
  5881 *** CTT ***
  5882 
  5883 * CTT: x-symbol support for Pi, Sigma, -->, : (membership); note that
  5884 "lam" is displayed as TWO lambda-symbols
  5885 
  5886 * CTT: theory Main now available, containing everything (that is, Bool
  5887 and Arith);
  5888 
  5889 
  5890 *** General ***
  5891 
  5892 * Pure: the Simplifier has been implemented properly as a derived rule
  5893 outside of the actual kernel (at last!); the overall performance
  5894 penalty in practical applications is about 50%, while reliability of
  5895 the Isabelle inference kernel has been greatly improved;
  5896 
  5897 * print modes "brackets" and "no_brackets" control output of nested =>
  5898 (types) and ==> (props); the default behaviour is "brackets";
  5899 
  5900 * Provers: fast_tac (and friends) now handle actual object-logic rules
  5901 as assumptions as well;
  5902 
  5903 * system: support Poly/ML 4.0;
  5904 
  5905 * system: isatool install handles KDE version 1 or 2;
  5906 
  5907 
  5908 
  5909 New in Isabelle99-1 (October 2000)
  5910 ----------------------------------
  5911 
  5912 *** Overview of INCOMPATIBILITIES ***
  5913 
  5914 * HOL: simplification of natural numbers is much changed; to partly
  5915 recover the old behaviour (e.g. to prevent n+n rewriting to #2*n)
  5916 issue the following ML commands:
  5917 
  5918   Delsimprocs Nat_Numeral_Simprocs.cancel_numerals;
  5919   Delsimprocs [Nat_Numeral_Simprocs.combine_numerals];
  5920 
  5921 * HOL: simplification no longer dives into case-expressions; this is
  5922 controlled by "t.weak_case_cong" for each datatype t;
  5923 
  5924 * HOL: nat_less_induct renamed to less_induct;
  5925 
  5926 * HOL: systematic renaming of the SOME (Eps) rules, may use isatool
  5927 fixsome to patch .thy and .ML sources automatically;
  5928 
  5929   select_equality  -> some_equality
  5930   select_eq_Ex     -> some_eq_ex
  5931   selectI2EX       -> someI2_ex
  5932   selectI2         -> someI2
  5933   selectI          -> someI
  5934   select1_equality -> some1_equality
  5935   Eps_sym_eq       -> some_sym_eq_trivial
  5936   Eps_eq           -> some_eq_trivial
  5937 
  5938 * HOL: exhaust_tac on datatypes superceded by new generic case_tac;
  5939 
  5940 * HOL: removed obsolete theorem binding expand_if (refer to split_if
  5941 instead);
  5942 
  5943 * HOL: the recursion equations generated by 'recdef' are now called
  5944 f.simps instead of f.rules;
  5945 
  5946 * HOL: qed_spec_mp now also handles bounded ALL as well;
  5947 
  5948 * HOL: 0 is now overloaded, so the type constraint ":: nat" may
  5949 sometimes be needed;
  5950 
  5951 * HOL: the constant for "f``x" is now "image" rather than "op ``";
  5952 
  5953 * HOL: the constant for "f-``x" is now "vimage" rather than "op -``";
  5954 
  5955 * HOL: the disjoint sum is now "<+>" instead of "Plus"; the cartesian
  5956 product is now "<*>" instead of "Times"; the lexicographic product is
  5957 now "<*lex*>" instead of "**";
  5958 
  5959 * HOL: theory Sexp is now in HOL/Induct examples (it used to be part
  5960 of main HOL, but was unused); better use HOL's datatype package;
  5961 
  5962 * HOL: removed "symbols" syntax for constant "override" of theory Map;
  5963 the old syntax may be recovered as follows:
  5964 
  5965   syntax (symbols)
  5966     override  :: "('a ~=> 'b) => ('a ~=> 'b) => ('a ~=> 'b)"
  5967       (infixl "\\<oplus>" 100)
  5968 
  5969 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  5970 
  5971 * HOL/ML: even fewer consts are declared as global (see theories Ord,
  5972 Lfp, Gfp, WF); this only affects ML packages that refer to const names
  5973 internally;
  5974 
  5975 * HOL and ZF: syntax for quotienting wrt an equivalence relation
  5976 changed from A/r to A//r;
  5977 
  5978 * ZF: new treatment of arithmetic (nat & int) may break some old
  5979 proofs;
  5980 
  5981 * Isar: renamed some attributes (RS -> THEN, simplify -> simplified,
  5982 rulify -> rule_format, elimify -> elim_format, ...);
  5983 
  5984 * Isar/Provers: intro/elim/dest attributes changed; renamed
  5985 intro/intro!/intro!! flags to intro!/intro/intro? (in most cases, one
  5986 should have to change intro!! to intro? only); replaced "delrule" by
  5987 "rule del";
  5988 
  5989 * Isar/HOL: renamed "intrs" to "intros" in inductive definitions;
  5990 
  5991 * Provers: strengthened force_tac by using new first_best_tac;
  5992 
  5993 * LaTeX document preparation: several changes of isabelle.sty (see
  5994 lib/texinputs);
  5995 
  5996 
  5997 *** Document preparation ***
  5998 
  5999 * formal comments (text blocks etc.) in new-style theories may now
  6000 contain antiquotations of thm/prop/term/typ/text to be presented
  6001 according to latex print mode; concrete syntax is like this:
  6002 @{term[show_types] "f(x) = a + x"};
  6003 
  6004 * isatool mkdir provides easy setup of Isabelle session directories,
  6005 including proper document sources;
  6006 
  6007 * generated LaTeX sources are now deleted after successful run
  6008 (isatool document -c); may retain a copy somewhere else via -D option
  6009 of isatool usedir;
  6010 
  6011 * isatool usedir -D now lets isatool latex -o sty update the Isabelle
  6012 style files, achieving self-contained LaTeX sources and simplifying
  6013 LaTeX debugging;
  6014 
  6015 * old-style theories now produce (crude) LaTeX output as well;
  6016 
  6017 * browser info session directories are now self-contained (may be put
  6018 on WWW server seperately); improved graphs of nested sessions; removed
  6019 graph for 'all sessions';
  6020 
  6021 * several improvements in isabelle style files; \isabellestyle{it}
  6022 produces fake math mode output; \isamarkupheader is now \section by
  6023 default; see lib/texinputs/isabelle.sty etc.;
  6024 
  6025 
  6026 *** Isar ***
  6027 
  6028 * Isar/Pure: local results and corresponding term bindings are now
  6029 subject to Hindley-Milner polymorphism (similar to ML); this
  6030 accommodates incremental type-inference very nicely;
  6031 
  6032 * Isar/Pure: new derived language element 'obtain' supports
  6033 generalized existence reasoning;
  6034 
  6035 * Isar/Pure: new calculational elements 'moreover' and 'ultimately'
  6036 support accumulation of results, without applying any rules yet;
  6037 useful to collect intermediate results without explicit name
  6038 references, and for use with transitivity rules with more than 2
  6039 premises;
  6040 
  6041 * Isar/Pure: scalable support for case-analysis type proofs: new
  6042 'case' language element refers to local contexts symbolically, as
  6043 produced by certain proof methods; internally, case names are attached
  6044 to theorems as "tags";
  6045 
  6046 * Isar/Pure: theory command 'hide' removes declarations from
  6047 class/type/const name spaces;
  6048 
  6049 * Isar/Pure: theory command 'defs' supports option "(overloaded)" to
  6050 indicate potential overloading;
  6051 
  6052 * Isar/Pure: changed syntax of local blocks from {{ }} to { };
  6053 
  6054 * Isar/Pure: syntax of sorts made 'inner', i.e. have to write
  6055 "{a,b,c}" instead of {a,b,c};
  6056 
  6057 * Isar/Pure now provides its own version of intro/elim/dest
  6058 attributes; useful for building new logics, but beware of confusion
  6059 with the version in Provers/classical;
  6060 
  6061 * Isar/Pure: the local context of (non-atomic) goals is provided via
  6062 case name 'antecedent';
  6063 
  6064 * Isar/Pure: removed obsolete 'transfer' attribute (transfer of thms
  6065 to the current context is now done automatically);
  6066 
  6067 * Isar/Pure: theory command 'method_setup' provides a simple interface
  6068 for definining proof methods in ML;
  6069 
  6070 * Isar/Provers: intro/elim/dest attributes changed; renamed
  6071 intro/intro!/intro!! flags to intro!/intro/intro? (INCOMPATIBILITY, in
  6072 most cases, one should have to change intro!! to intro? only);
  6073 replaced "delrule" by "rule del";
  6074 
  6075 * Isar/Provers: new 'hypsubst' method, plain 'subst' method and
  6076 'symmetric' attribute (the latter supercedes [RS sym]);
  6077 
  6078 * Isar/Provers: splitter support (via 'split' attribute and 'simp'
  6079 method modifier); 'simp' method: 'only:' modifier removes loopers as
  6080 well (including splits);
  6081 
  6082 * Isar/Provers: Simplifier and Classical methods now support all kind
  6083 of modifiers used in the past, including 'cong', 'iff', etc.
  6084 
  6085 * Isar/Provers: added 'fastsimp' and 'clarsimp' methods (combination
  6086 of Simplifier and Classical reasoner);
  6087 
  6088 * Isar/HOL: new proof method 'cases' and improved version of 'induct'
  6089 now support named cases; major packages (inductive, datatype, primrec,
  6090 recdef) support case names and properly name parameters;
  6091 
  6092 * Isar/HOL: new transitivity rules for substitution in inequalities --
  6093 monotonicity conditions are extracted to be proven at end of
  6094 calculations;
  6095 
  6096 * Isar/HOL: removed 'case_split' thm binding, should use 'cases' proof
  6097 method anyway;
  6098 
  6099 * Isar/HOL: removed old expand_if = split_if; theorems if_splits =
  6100 split_if split_if_asm; datatype package provides theorems foo.splits =
  6101 foo.split foo.split_asm for each datatype;
  6102 
  6103 * Isar/HOL: tuned inductive package, rename "intrs" to "intros"
  6104 (potential INCOMPATIBILITY), emulation of mk_cases feature for proof
  6105 scripts: new 'inductive_cases' command and 'ind_cases' method; (Note:
  6106 use "(cases (simplified))" method in proper proof texts);
  6107 
  6108 * Isar/HOL: added global 'arith_split' attribute for 'arith' method;
  6109 
  6110 * Isar: names of theorems etc. may be natural numbers as well;
  6111 
  6112 * Isar: 'pr' command: optional arguments for goals_limit and
  6113 ProofContext.prems_limit; no longer prints theory contexts, but only
  6114 proof states;
  6115 
  6116 * Isar: diagnostic commands 'pr', 'thm', 'prop', 'term', 'typ' admit
  6117 additional print modes to be specified; e.g. "pr(latex)" will print
  6118 proof state according to the Isabelle LaTeX style;
  6119 
  6120 * Isar: improved support for emulating tactic scripts, including proof
  6121 methods 'rule_tac' etc., 'cut_tac', 'thin_tac', 'subgoal_tac',
  6122 'rename_tac', 'rotate_tac', 'tactic', and 'case_tac' / 'induct_tac'
  6123 (for HOL datatypes);
  6124 
  6125 * Isar: simplified (more robust) goal selection of proof methods: 1st
  6126 goal, all goals, or explicit goal specifier (tactic emulation); thus
  6127 'proof method scripts' have to be in depth-first order;
  6128 
  6129 * Isar: tuned 'let' syntax: replaced 'as' keyword by 'and';
  6130 
  6131 * Isar: removed 'help' command, which hasn't been too helpful anyway;
  6132 should instead use individual commands for printing items
  6133 (print_commands, print_methods etc.);
  6134 
  6135 * Isar: added 'nothing' --- the empty list of theorems;
  6136 
  6137 
  6138 *** HOL ***
  6139 
  6140 * HOL/MicroJava: formalization of a fragment of Java, together with a
  6141 corresponding virtual machine and a specification of its bytecode
  6142 verifier and a lightweight bytecode verifier, including proofs of
  6143 type-safety; by Gerwin Klein, Tobias Nipkow, David von Oheimb, and
  6144 Cornelia Pusch (see also the homepage of project Bali at
  6145 http://isabelle.in.tum.de/Bali/);
  6146 
  6147 * HOL/Algebra: new theory of rings and univariate polynomials, by
  6148 Clemens Ballarin;
  6149 
  6150 * HOL/NumberTheory: fundamental Theorem of Arithmetic, Chinese
  6151 Remainder Theorem, Fermat/Euler Theorem, Wilson's Theorem, by Thomas M
  6152 Rasmussen;
  6153 
  6154 * HOL/Lattice: fundamental concepts of lattice theory and order
  6155 structures, including duals, properties of bounds versus algebraic
  6156 laws, lattice operations versus set-theoretic ones, the Knaster-Tarski
  6157 Theorem for complete lattices etc.; may also serve as a demonstration
  6158 for abstract algebraic reasoning using axiomatic type classes, and
  6159 mathematics-style proof in Isabelle/Isar; by Markus Wenzel;
  6160 
  6161 * HOL/Prolog: a (bare-bones) implementation of Lambda-Prolog, by David
  6162 von Oheimb;
  6163 
  6164 * HOL/IMPP: extension of IMP with local variables and mutually
  6165 recursive procedures, by David von Oheimb;
  6166 
  6167 * HOL/Lambda: converted into new-style theory and document;
  6168 
  6169 * HOL/ex/Multiquote: example of multiple nested quotations and
  6170 anti-quotations -- basically a generalized version of de-Bruijn
  6171 representation; very useful in avoiding lifting of operations;
  6172 
  6173 * HOL/record: added general record equality rule to simpset; fixed
  6174 select-update simplification procedure to handle extended records as
  6175 well; admit "r" as field name;
  6176 
  6177 * HOL: 0 is now overloaded over the new sort "zero", allowing its use with
  6178 other numeric types and also as the identity of groups, rings, etc.;
  6179 
  6180 * HOL: new axclass plus_ac0 for addition with the AC-laws and 0 as identity.
  6181 Types nat and int belong to this axclass;
  6182 
  6183 * HOL: greatly improved simplification involving numerals of type nat, int, real:
  6184    (i + #8 + j) = Suc k simplifies to  #7 + (i + j) = k
  6185    i*j + k + j*#3*i     simplifies to  #4*(i*j) + k
  6186   two terms #m*u and #n*u are replaced by #(m+n)*u
  6187     (where #m, #n and u can implicitly be 1; this is simproc combine_numerals)
  6188   and the term/formula #m*u+x ~~ #n*u+y simplifies simplifies to #(m-n)+x ~~ y
  6189     or x ~~ #(n-m)+y, where ~~ is one of = < <= or - (simproc cancel_numerals);
  6190 
  6191 * HOL: meson_tac is available (previously in ex/meson.ML); it is a
  6192 powerful prover for predicate logic but knows nothing of clasets; see
  6193 ex/mesontest.ML and ex/mesontest2.ML for example applications;
  6194 
  6195 * HOL: new version of "case_tac" subsumes both boolean case split and
  6196 "exhaust_tac" on datatypes; INCOMPATIBILITY: exhaust_tac no longer
  6197 exists, may define val exhaust_tac = case_tac for ad-hoc portability;
  6198 
  6199 * HOL: simplification no longer dives into case-expressions: only the
  6200 selector expression is simplified, but not the remaining arms; to
  6201 enable full simplification of case-expressions for datatype t, you may
  6202 remove t.weak_case_cong from the simpset, either globally (Delcongs
  6203 [thm"t.weak_case_cong"];) or locally (delcongs [...]).
  6204 
  6205 * HOL/recdef: the recursion equations generated by 'recdef' for
  6206 function 'f' are now called f.simps instead of f.rules; if all
  6207 termination conditions are proved automatically, these simplification
  6208 rules are added to the simpset, as in primrec; rules may be named
  6209 individually as well, resulting in a separate list of theorems for
  6210 each equation;
  6211 
  6212 * HOL/While is a new theory that provides a while-combinator. It
  6213 permits the definition of tail-recursive functions without the
  6214 provision of a termination measure. The latter is necessary once the
  6215 invariant proof rule for while is applied.
  6216 
  6217 * HOL: new (overloaded) notation for the set of elements below/above
  6218 some element: {..u}, {..u(}, {l..}, {)l..}. See theory SetInterval.
  6219 
  6220 * HOL: theorems impI, allI, ballI bound as "strip";
  6221 
  6222 * HOL: new tactic induct_thm_tac: thm -> string -> int -> tactic
  6223 induct_tac th "x1 ... xn" expects th to have a conclusion of the form
  6224 P v1 ... vn and abbreviates res_inst_tac [("v1","x1"),...,("vn","xn")] th;
  6225 
  6226 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  6227 
  6228 * HOL: theory Sexp now in HOL/Induct examples (it used to be part of
  6229 main HOL, but was unused);
  6230 
  6231 * HOL: fewer consts declared as global (e.g. have to refer to
  6232 "Lfp.lfp" instead of "lfp" internally; affects ML packages only);