NEWS
author blanchet
Tue Oct 05 11:45:10 2010 +0200 (2010-10-05)
changeset 39953 aa54f347e5e2
parent 39910 10097e0a9dbd
child 39916 8c83139a1433
child 39957 2f2d90cc31a2
permissions -rw-r--r--
hide uninteresting MESON/Metis constants and facts and remove "meson_" prefix to (now hidden) fact names
     1 Isabelle NEWS -- history user-relevant changes
     2 ==============================================
     3 
     4 New in this Isabelle version
     5 ----------------------------
     6 
     7 *** General ***
     8 
     9 * Explicit treatment of UTF8 sequences as Isabelle symbols, such that
    10 a Unicode character is treated as a single symbol, not a sequence of
    11 non-ASCII bytes as before.  Since Isabelle/ML string literals may
    12 contain symbols without further backslash escapes, Unicode can now be
    13 used here as well.  Recall that Symbol.explode in ML provides a
    14 consistent view on symbols, while raw explode (or String.explode)
    15 merely give a byte-oriented representation.
    16 
    17 * Theory loading: only the master source file is looked-up in the
    18 implicit load path, all other files are addressed relatively to its
    19 directory.  Minor INCOMPATIBILITY, subtle change in semantics.
    20 
    21 * Special treatment of ML file names has been discontinued.
    22 Historically, optional extensions .ML or .sml were added on demand --
    23 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
    24 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
    25 
    26 * Various options that affect pretty printing etc. are now properly
    27 handled within the context via configuration options, instead of
    28 unsynchronized references.  There are both ML Config.T entities and
    29 Isar declaration attributes to access these.
    30 
    31   ML (Config.T)                 Isar (attribute)
    32 
    33   eta_contract                  eta_contract
    34   show_brackets                 show_brackets
    35   show_sorts                    show_sorts
    36   show_types                    show_types
    37   show_question_marks           show_question_marks
    38   show_consts                   show_consts
    39 
    40   Syntax.ambiguity_level        syntax_ambiguity_level
    41 
    42   Goal_Display.goals_limit      goals_limit
    43   Goal_Display.show_main_goal   show_main_goal
    44 
    45   Thy_Output.display            thy_output_display
    46   Thy_Output.quotes             thy_output_quotes
    47   Thy_Output.indent             thy_output_indent
    48   Thy_Output.source             thy_output_source
    49   Thy_Output.break              thy_output_break
    50 
    51 Note that corresponding "..._default" references in ML may be only
    52 changed globally at the ROOT session setup, but *not* within a theory.
    53 
    54 
    55 *** Pure ***
    56 
    57 * Interpretation command 'interpret' accepts a list of equations like
    58 'interpretation' does.
    59 
    60 * Diagnostic command 'print_interps' prints interpretations in proofs
    61 in addition to interpretations in theories.
    62 
    63 * Discontinued obsolete 'global' and 'local' commands to manipulate
    64 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
    65 Sign.root_path and Sign.local_path may be applied directly where this
    66 feature is still required for historical reasons.
    67 
    68 * Discontinued ancient 'constdefs' command.  INCOMPATIBILITY, use
    69 'definition' instead.
    70 
    71 * Document antiquotations @{class} and @{type} for printing classes
    72 and type constructors.
    73 
    74 
    75 *** HOL ***
    76 
    77 * Constant `contents` renamed to `the_elem`, to free the generic name
    78 contents for other uses.  INCOMPATIBILITY.
    79 
    80 * Dropped old primrec package.  INCOMPATIBILITY.
    81 
    82 * Improved infrastructure for term evaluation using code generator
    83 techniques, in particular static evaluation conversions.
    84 
    85 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
    86  
    87 * Renamed lemmas:
    88   expand_fun_eq -> fun_eq_iff
    89   expand_set_eq -> set_eq_iff
    90   set_ext -> set_eqI
    91  INCOMPATIBILITY.
    92 
    93 * Renamed class eq and constant eq (for code generation) to class equal
    94 and constant equal, plus renaming of related facts and various tuning.
    95 INCOMPATIBILITY.
    96 
    97 * Scala (2.8 or higher) has been added to the target languages of
    98 the code generator.
    99 
   100 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   101 
   102 * Theory SetsAndFunctions has been split into Function_Algebras and Set_Algebras;
   103 canonical names for instance definitions for functions; various improvements.
   104 INCOMPATIBILITY.
   105 
   106 * Records: logical foundation type for records do not carry a '_type' suffix
   107 any longer.  INCOMPATIBILITY.
   108 
   109 * Code generation for records: more idiomatic representation of record types.
   110 Warning: records are not covered by ancient SML code generation any longer.
   111 INCOMPATIBILITY.  In cases of need, a suitable rep_datatype declaration
   112 helps to succeed then:
   113 
   114   record 'a foo = ...
   115   ...
   116   rep_datatype foo_ext ...
   117 
   118 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   119 INCOMPATIBILITY.
   120 
   121 * Quickcheck in locales considers interpretations of that locale for
   122 counter example search.
   123 
   124 * Theory Library/Monad_Syntax provides do-syntax for monad types.  Syntax
   125 in Library/State_Monad has been changed to avoid ambiguities.
   126 INCOMPATIBILITY.
   127 
   128 * Code generator: export_code without explicit file declaration prints
   129 to standard output.  INCOMPATIBILITY.
   130 
   131 * Abolished symbol type names:  "prod" and "sum" replace "*" and "+"
   132 respectively.  INCOMPATIBILITY.
   133 
   134 * Constant "split" has been merged with constant "prod_case";  names
   135 of ML functions, facts etc. involving split have been retained so far,
   136 though.  INCOMPATIBILITY.
   137 
   138 * Dropped old infix syntax "mem" for List.member;  use "in set"
   139 instead.  INCOMPATIBILITY.
   140 
   141 * Refactoring of code-generation specific operations in List.thy
   142 
   143   constants
   144     null ~> List.null
   145 
   146   facts
   147     mem_iff ~> member_def
   148     null_empty ~> null_def
   149 
   150 INCOMPATIBILITY.  Note that these were not suppossed to be used
   151 regularly unless for striking reasons;  their main purpose was code
   152 generation.
   153 
   154 * Some previously unqualified names have been qualified:
   155 
   156   types
   157     bool ~> HOL.bool
   158     nat ~> Nat.nat
   159 
   160   constants
   161     Trueprop ~> HOL.Trueprop
   162     True ~> HOL.True
   163     False ~> HOL.False
   164     op & ~> HOL.conj
   165     op | ~> HOL.disj
   166     op --> ~> HOL.implies
   167     op = ~> HOL.eq
   168     Not ~> HOL.Not
   169     The ~> HOL.The
   170     All ~> HOL.All
   171     Ex ~> HOL.Ex
   172     Ex1 ~> HOL.Ex1
   173     Let ~> HOL.Let
   174     If ~> HOL.If
   175     Ball ~> Set.Ball
   176     Bex ~> Set.Bex
   177     Suc ~> Nat.Suc
   178     Pair ~> Product_Type.Pair
   179     fst ~> Product_Type.fst
   180     snd ~> Product_Type.snd
   181     curry ~> Product_Type.curry
   182     op : ~> Set.member
   183     Collect ~> Set.Collect
   184 
   185 INCOMPATIBILITY.
   186 
   187 * Removed simplifier congruence rule of "prod_case", as has for long
   188 been the case with "split".  INCOMPATIBILITY.
   189 
   190 * Datatype package: theorems generated for executable equality
   191 (class eq) carry proper names and are treated as default code
   192 equations.
   193 
   194 * Removed lemma Option.is_none_none (Duplicate of is_none_def).
   195 INCOMPATIBILITY.
   196 
   197 * List.thy: use various operations from the Haskell prelude when
   198 generating Haskell code.
   199 
   200 * Multiset.thy: renamed empty_idemp -> empty_neutral
   201 
   202 * code_simp.ML and method code_simp: simplification with rules determined
   203 by code generator.
   204 
   205 * code generator: do not print function definitions for case
   206 combinators any longer.
   207 
   208 * Multivariate Analysis: Introduced a type class for euclidean space. Most
   209 theorems are now stated in terms of euclidean spaces instead of finite
   210 cartesian products.
   211 
   212   types
   213     real ^ 'n ~>  'a::real_vector
   214               ~>  'a::euclidean_space
   215               ~>  'a::ordered_euclidean_space
   216         (depends on your needs)
   217 
   218   constants
   219      _ $ _        ~> _ $$ _
   220      \<chi> x. _  ~> \<chi>\<chi> x. _
   221      CARD('n)     ~> DIM('a)
   222 
   223 Also note that the indices are now natural numbers and not from some finite
   224 type. Finite cartesian products of euclidean spaces, products of euclidean
   225 spaces the real and complex numbers are instantiated to be euclidean_spaces.
   226 
   227 INCOMPATIBILITY.
   228 
   229 * Probability: Introduced pinfreal as real numbers with infinity. Use pinfreal
   230 as value for measures. Introduces Lebesgue Measure based on the integral in
   231 Multivariate Analysis. Proved Radon Nikodym for arbitrary sigma finite measure
   232 spaces.
   233 
   234  INCOMPATIBILITY.
   235 
   236 * Inductive package: offers new command "inductive_simps" to automatically
   237 derive instantiated and simplified equations for inductive predicates,
   238 similar to inductive_cases.
   239 
   240 * "bij f" is now an abbreviation of "bij_betw f UNIV UNIV". surj_on is a
   241 generalization of surj, and "surj f" is now a abbreviation of "surj_on f UNIV".
   242 The theorems bij_def and surj_def are unchanged.
   243 
   244 * Function package: .psimps rules are no longer implicitly declared [simp].
   245 INCOMPATIBILITY.
   246 
   247 *** FOL ***
   248 
   249 * All constant names are now qualified.  INCOMPATIBILITY.
   250 
   251 
   252 *** ZF ***
   253 
   254 * All constant names are now qualified.  INCOMPATIBILITY.
   255 
   256 
   257 *** ML ***
   258 
   259 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   260 meaning.
   261 
   262 * Renamed structure PureThy to Pure_Thy and moved most of its
   263 operations to structure Global_Theory, to emphasize that this is
   264 rarely-used global-only stuff.
   265 
   266 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
   267 instead (or tracing for high-volume output).
   268 
   269 * Configuration option show_question_marks only affects regular pretty
   270 printing of types and terms, not raw Term.string_of_vname.
   271 
   272 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
   273 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
   274 @{thms} for most purposes.
   275 
   276 * ML structure Unsynchronized never opened, not even in Isar
   277 interaction mode as before.  Old Unsynchronized.set etc. have been
   278 discontinued -- use plain := instead.  This should be *rare* anyway,
   279 since modern tools always work via official context data, notably
   280 configuration options.
   281 
   282 * ML antiquotations @{theory} and @{theory_ref} refer to named
   283 theories from the ancestry of the current context, not any accidental
   284 theory loader state as before.  Potential INCOMPATIBILITY, subtle
   285 change in semantics.
   286 
   287 * Parallel and asynchronous execution requires special care concerning
   288 interrupts.  Structure Exn provides some convenience functions that
   289 avoid working directly with raw Interrupt.  User code must not absorb
   290 interrupts -- intermediate handling (for cleanup etc.) needs to be
   291 followed by re-raising of the original exception.  Another common
   292 source of mistakes are "handle _" patterns, which make the meaning of
   293 the program subject to physical effects of the environment.
   294 
   295 
   296 *** System ***
   297 
   298 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   299 
   300 
   301 
   302 New in Isabelle2009-2 (June 2010)
   303 ---------------------------------
   304 
   305 *** General ***
   306 
   307 * Authentic syntax for *all* logical entities (type classes, type
   308 constructors, term constants): provides simple and robust
   309 correspondence between formal entities and concrete syntax.  Within
   310 the parse tree / AST representations, "constants" are decorated by
   311 their category (class, type, const) and spelled out explicitly with
   312 their full internal name.
   313 
   314 Substantial INCOMPATIBILITY concerning low-level syntax declarations
   315 and translations (translation rules and translation functions in ML).
   316 Some hints on upgrading:
   317 
   318   - Many existing uses of 'syntax' and 'translations' can be replaced
   319     by more modern 'type_notation', 'notation' and 'abbreviation',
   320     which are independent of this issue.
   321 
   322   - 'translations' require markup within the AST; the term syntax
   323     provides the following special forms:
   324 
   325       CONST c   -- produces syntax version of constant c from context
   326       XCONST c  -- literally c, checked as constant from context
   327       c         -- literally c, if declared by 'syntax'
   328 
   329     Plain identifiers are treated as AST variables -- occasionally the
   330     system indicates accidental variables via the error "rhs contains
   331     extra variables".
   332 
   333     Type classes and type constructors are marked according to their
   334     concrete syntax.  Some old translations rules need to be written
   335     for the "type" category, using type constructor application
   336     instead of pseudo-term application of the default category
   337     "logic".
   338 
   339   - 'parse_translation' etc. in ML may use the following
   340     antiquotations:
   341 
   342       @{class_syntax c}   -- type class c within parse tree / AST
   343       @{term_syntax c}    -- type constructor c within parse tree / AST
   344       @{const_syntax c}   -- ML version of "CONST c" above
   345       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
   346 
   347   - Literal types within 'typed_print_translations', i.e. those *not*
   348     represented as pseudo-terms are represented verbatim.  Use @{class
   349     c} or @{type_name c} here instead of the above syntax
   350     antiquotations.
   351 
   352 Note that old non-authentic syntax was based on unqualified base
   353 names, so all of the above "constant" names would coincide.  Recall
   354 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
   355 diagnose syntax problems.
   356 
   357 * Type constructors admit general mixfix syntax, not just infix.
   358 
   359 * Concrete syntax may be attached to local entities without a proof
   360 body, too.  This works via regular mixfix annotations for 'fix',
   361 'def', 'obtain' etc. or via the explicit 'write' command, which is
   362 similar to the 'notation' command in theory specifications.
   363 
   364 * Discontinued unnamed infix syntax (legacy feature for many years) --
   365 need to specify constant name and syntax separately.  Internal ML
   366 datatype constructors have been renamed from InfixName to Infix etc.
   367 Minor INCOMPATIBILITY.
   368 
   369 * Schematic theorem statements need to be explicitly markup as such,
   370 via commands 'schematic_lemma', 'schematic_theorem',
   371 'schematic_corollary'.  Thus the relevance of the proof is made
   372 syntactically clear, which impacts performance in a parallel or
   373 asynchronous interactive environment.  Minor INCOMPATIBILITY.
   374 
   375 * Use of cumulative prems via "!" in some proof methods has been
   376 discontinued (old legacy feature).
   377 
   378 * References 'trace_simp' and 'debug_simp' have been replaced by
   379 configuration options stored in the context. Enabling tracing (the
   380 case of debugging is similar) in proofs works via
   381 
   382   using [[trace_simp = true]]
   383 
   384 Tracing is then active for all invocations of the simplifier in
   385 subsequent goal refinement steps. Tracing may also still be enabled or
   386 disabled via the ProofGeneral settings menu.
   387 
   388 * Separate commands 'hide_class', 'hide_type', 'hide_const',
   389 'hide_fact' replace the former 'hide' KIND command.  Minor
   390 INCOMPATIBILITY.
   391 
   392 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
   393 more efficient than combinations with -q1 or -q2.
   394 
   395 
   396 *** Pure ***
   397 
   398 * Proofterms record type-class reasoning explicitly, using the
   399 "unconstrain" operation internally.  This eliminates all sort
   400 constraints from a theorem and proof, introducing explicit
   401 OFCLASS-premises.  On the proof term level, this operation is
   402 automatically applied at theorem boundaries, such that closed proofs
   403 are always free of sort constraints.  INCOMPATIBILITY for tools that
   404 inspect proof terms.
   405 
   406 * Local theory specifications may depend on extra type variables that
   407 are not present in the result type -- arguments TYPE('a) :: 'a itself
   408 are added internally.  For example:
   409 
   410   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
   411 
   412 * Predicates of locales introduced by classes carry a mandatory
   413 "class" prefix.  INCOMPATIBILITY.
   414 
   415 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
   416 
   417 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
   418 'class' instead.
   419 
   420 * Command 'code_reflect' allows to incorporate generated ML code into
   421 runtime environment; replaces immature code_datatype antiquotation.
   422 INCOMPATIBILITY.
   423 
   424 * Code generator: simple concept for abstract datatypes obeying
   425 invariants.
   426 
   427 * Code generator: details of internal data cache have no impact on the
   428 user space functionality any longer.
   429 
   430 * Methods "unfold_locales" and "intro_locales" ignore non-locale
   431 subgoals.  This is more appropriate for interpretations with 'where'.
   432 INCOMPATIBILITY.
   433 
   434 * Command 'example_proof' opens an empty proof body.  This allows to
   435 experiment with Isar, without producing any persistent result.
   436 
   437 * Commands 'type_notation' and 'no_type_notation' declare type syntax
   438 within a local theory context, with explicit checking of the
   439 constructors involved (in contrast to the raw 'syntax' versions).
   440 
   441 * Commands 'types' and 'typedecl' now work within a local theory
   442 context -- without introducing dependencies on parameters or
   443 assumptions, which is not possible in Isabelle/Pure.
   444 
   445 * Command 'defaultsort' has been renamed to 'default_sort', it works
   446 within a local theory context.  Minor INCOMPATIBILITY.
   447 
   448 
   449 *** HOL ***
   450 
   451 * Command 'typedef' now works within a local theory context -- without
   452 introducing dependencies on parameters or assumptions, which is not
   453 possible in Isabelle/Pure/HOL.  Note that the logical environment may
   454 contain multiple interpretations of local typedefs (with different
   455 non-emptiness proofs), even in a global theory context.
   456 
   457 * New package for quotient types.  Commands 'quotient_type' and
   458 'quotient_definition' may be used for defining types and constants by
   459 quotient constructions.  An example is the type of integers created by
   460 quotienting pairs of natural numbers:
   461 
   462   fun
   463     intrel :: "(nat * nat) => (nat * nat) => bool"
   464   where
   465     "intrel (x, y) (u, v) = (x + v = u + y)"
   466 
   467   quotient_type int = "nat * nat" / intrel
   468     by (auto simp add: equivp_def expand_fun_eq)
   469 
   470   quotient_definition
   471     "0::int" is "(0::nat, 0::nat)"
   472 
   473 The method "lifting" can be used to lift of theorems from the
   474 underlying "raw" type to the quotient type.  The example
   475 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
   476 construction and provides a reasoning infrastructure for finite sets.
   477 
   478 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
   479 clash with new theory Quotient in Main HOL.
   480 
   481 * Moved the SMT binding into the main HOL session, eliminating
   482 separate HOL-SMT session.
   483 
   484 * List membership infix mem operation is only an input abbreviation.
   485 INCOMPATIBILITY.
   486 
   487 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
   488 for future developements; former Library/Word.thy is still present in
   489 the AFP entry RSAPPS.
   490 
   491 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
   492 longer shadowed.  INCOMPATIBILITY.
   493 
   494 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
   495 INCOMPATIBILITY.
   496 
   497 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
   498 INCOMPATIBILITY.
   499 
   500 * Dropped normalizing_semiring etc; use the facts in semiring classes
   501 instead.  INCOMPATIBILITY.
   502 
   503 * Dropped several real-specific versions of lemmas about floor and
   504 ceiling; use the generic lemmas from theory "Archimedean_Field"
   505 instead.  INCOMPATIBILITY.
   506 
   507   floor_number_of_eq         ~> floor_number_of
   508   le_floor_eq_number_of      ~> number_of_le_floor
   509   le_floor_eq_zero           ~> zero_le_floor
   510   le_floor_eq_one            ~> one_le_floor
   511   floor_less_eq_number_of    ~> floor_less_number_of
   512   floor_less_eq_zero         ~> floor_less_zero
   513   floor_less_eq_one          ~> floor_less_one
   514   less_floor_eq_number_of    ~> number_of_less_floor
   515   less_floor_eq_zero         ~> zero_less_floor
   516   less_floor_eq_one          ~> one_less_floor
   517   floor_le_eq_number_of      ~> floor_le_number_of
   518   floor_le_eq_zero           ~> floor_le_zero
   519   floor_le_eq_one            ~> floor_le_one
   520   floor_subtract_number_of   ~> floor_diff_number_of
   521   floor_subtract_one         ~> floor_diff_one
   522   ceiling_number_of_eq       ~> ceiling_number_of
   523   ceiling_le_eq_number_of    ~> ceiling_le_number_of
   524   ceiling_le_zero_eq         ~> ceiling_le_zero
   525   ceiling_le_eq_one          ~> ceiling_le_one
   526   less_ceiling_eq_number_of  ~> number_of_less_ceiling
   527   less_ceiling_eq_zero       ~> zero_less_ceiling
   528   less_ceiling_eq_one        ~> one_less_ceiling
   529   ceiling_less_eq_number_of  ~> ceiling_less_number_of
   530   ceiling_less_eq_zero       ~> ceiling_less_zero
   531   ceiling_less_eq_one        ~> ceiling_less_one
   532   le_ceiling_eq_number_of    ~> number_of_le_ceiling
   533   le_ceiling_eq_zero         ~> zero_le_ceiling
   534   le_ceiling_eq_one          ~> one_le_ceiling
   535   ceiling_subtract_number_of ~> ceiling_diff_number_of
   536   ceiling_subtract_one       ~> ceiling_diff_one
   537 
   538 * Theory "Finite_Set": various folding_XXX locales facilitate the
   539 application of the various fold combinators on finite sets.
   540 
   541 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
   542 provides abstract red-black tree type which is backed by "RBT_Impl" as
   543 implementation.  INCOMPATIBILTY.
   544 
   545 * Theory Library/Coinductive_List has been removed -- superseded by
   546 AFP/thys/Coinductive.
   547 
   548 * Theory PReal, including the type "preal" and related operations, has
   549 been removed.  INCOMPATIBILITY.
   550 
   551 * Real: new development using Cauchy Sequences.
   552 
   553 * Split off theory "Big_Operators" containing setsum, setprod,
   554 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
   555 
   556 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
   557 "Int" etc.  INCOMPATIBILITY.
   558 
   559 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
   560 
   561 * New set of rules "ac_simps" provides combined assoc / commute
   562 rewrites for all interpretations of the appropriate generic locales.
   563 
   564 * Renamed theory "OrderedGroup" to "Groups" and split theory
   565 "Ring_and_Field" into theories "Rings" and "Fields"; for more
   566 appropriate and more consistent names suitable for name prefixes
   567 within the HOL theories.  INCOMPATIBILITY.
   568 
   569 * Some generic constants have been put to appropriate theories:
   570   - less_eq, less: Orderings
   571   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
   572   - inverse, divide: Rings
   573 INCOMPATIBILITY.
   574 
   575 * More consistent naming of type classes involving orderings (and
   576 lattices):
   577 
   578     lower_semilattice                   ~> semilattice_inf
   579     upper_semilattice                   ~> semilattice_sup
   580 
   581     dense_linear_order                  ~> dense_linorder
   582 
   583     pordered_ab_group_add               ~> ordered_ab_group_add
   584     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
   585     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
   586     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
   587     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
   588     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
   589     pordered_cancel_semiring            ~> ordered_cancel_semiring
   590     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
   591     pordered_comm_ring                  ~> ordered_comm_ring
   592     pordered_comm_semiring              ~> ordered_comm_semiring
   593     pordered_ring                       ~> ordered_ring
   594     pordered_ring_abs                   ~> ordered_ring_abs
   595     pordered_semiring                   ~> ordered_semiring
   596 
   597     ordered_ab_group_add                ~> linordered_ab_group_add
   598     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
   599     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
   600     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
   601     ordered_field                       ~> linordered_field
   602     ordered_field_no_lb                 ~> linordered_field_no_lb
   603     ordered_field_no_ub                 ~> linordered_field_no_ub
   604     ordered_field_dense_linear_order    ~> dense_linordered_field
   605     ordered_idom                        ~> linordered_idom
   606     ordered_ring                        ~> linordered_ring
   607     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
   608     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
   609     ordered_ring_strict                 ~> linordered_ring_strict
   610     ordered_semidom                     ~> linordered_semidom
   611     ordered_semiring                    ~> linordered_semiring
   612     ordered_semiring_1                  ~> linordered_semiring_1
   613     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
   614     ordered_semiring_strict             ~> linordered_semiring_strict
   615 
   616   The following slightly odd type classes have been moved to a
   617   separate theory Library/Lattice_Algebras:
   618 
   619     lordered_ab_group_add               ~> lattice_ab_group_add
   620     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
   621     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
   622     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
   623     lordered_ring                       ~> lattice_ring
   624 
   625 INCOMPATIBILITY.
   626 
   627 * Refined field classes:
   628   - classes division_ring_inverse_zero, field_inverse_zero,
   629     linordered_field_inverse_zero include rule inverse 0 = 0 --
   630     subsumes former division_by_zero class;
   631   - numerous lemmas have been ported from field to division_ring.
   632 INCOMPATIBILITY.
   633 
   634 * Refined algebra theorem collections:
   635   - dropped theorem group group_simps, use algebra_simps instead;
   636   - dropped theorem group ring_simps, use field_simps instead;
   637   - proper theorem collection field_simps subsumes former theorem
   638     groups field_eq_simps and field_simps;
   639   - dropped lemma eq_minus_self_iff which is a duplicate for
   640     equal_neg_zero.
   641 INCOMPATIBILITY.
   642 
   643 * Theory Finite_Set and List: some lemmas have been generalized from
   644 sets to lattices:
   645 
   646   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
   647   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
   648   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
   649   union_Union_fold_union        ~> sup_Sup_fold_sup
   650   Inter_fold_inter              ~> Inf_fold_inf
   651   Union_fold_union              ~> Sup_fold_sup
   652   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
   653   union_UNION_fold_union        ~> sup_SUPR_fold_sup
   654   INTER_fold_inter              ~> INFI_fold_inf
   655   UNION_fold_union              ~> SUPR_fold_sup
   656 
   657 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
   658 replaced by the more convenient lemmas Inf_empty and Sup_empty.
   659 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
   660 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
   661 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
   662 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
   663 
   664 * Reorganized theory Multiset: swapped notation of pointwise and
   665 multiset order:
   666 
   667   - pointwise ordering is instance of class order with standard syntax
   668     <= and <;
   669   - multiset ordering has syntax <=# and <#; partial order properties
   670     are provided by means of interpretation with prefix
   671     multiset_order;
   672   - less duplication, less historical organization of sections,
   673     conversion from associations lists to multisets, rudimentary code
   674     generation;
   675   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
   676     if needed.
   677 
   678 Renamed:
   679 
   680   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
   681   multi_count_ext  ~>  multiset_ext
   682   diff_union_inverse2  ~>  diff_union_cancelR
   683 
   684 INCOMPATIBILITY.
   685 
   686 * Theory Permutation: replaced local "remove" by List.remove1.
   687 
   688 * Code generation: ML and OCaml code is decorated with signatures.
   689 
   690 * Theory List: added transpose.
   691 
   692 * Library/Nat_Bijection.thy is a collection of bijective functions
   693 between nat and other types, which supersedes the older libraries
   694 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
   695 
   696   Constants:
   697   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
   698   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
   699   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
   700   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
   701   Countable.pair_encode           ~> prod_encode
   702   NatIso.prod2nat                 ~> prod_encode
   703   NatIso.nat2prod                 ~> prod_decode
   704   NatIso.sum2nat                  ~> sum_encode
   705   NatIso.nat2sum                  ~> sum_decode
   706   NatIso.list2nat                 ~> list_encode
   707   NatIso.nat2list                 ~> list_decode
   708   NatIso.set2nat                  ~> set_encode
   709   NatIso.nat2set                  ~> set_decode
   710 
   711   Lemmas:
   712   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
   713   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
   714   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
   715   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
   716   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
   717   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
   718   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
   719   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
   720   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
   721   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
   722   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
   723   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
   724   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
   725 
   726 * Sledgehammer:
   727   - Renamed ATP commands:
   728     atp_info     ~> sledgehammer running_atps
   729     atp_kill     ~> sledgehammer kill_atps
   730     atp_messages ~> sledgehammer messages
   731     atp_minimize ~> sledgehammer minimize
   732     print_atps   ~> sledgehammer available_atps
   733     INCOMPATIBILITY.
   734   - Added user's manual ("isabelle doc sledgehammer").
   735   - Added option syntax and "sledgehammer_params" to customize
   736     Sledgehammer's behavior.  See the manual for details.
   737   - Modified the Isar proof reconstruction code so that it produces
   738     direct proofs rather than proofs by contradiction.  (This feature
   739     is still experimental.)
   740   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
   741     full-typed mode.
   742   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
   743 
   744 * Nitpick:
   745   - Added and implemented "binary_ints" and "bits" options.
   746   - Added "std" option and implemented support for nonstandard models.
   747   - Added and implemented "finitize" option to improve the precision
   748     of infinite datatypes based on a monotonicity analysis.
   749   - Added support for quotient types.
   750   - Added support for "specification" and "ax_specification"
   751     constructs.
   752   - Added support for local definitions (for "function" and
   753     "termination" proofs).
   754   - Added support for term postprocessors.
   755   - Optimized "Multiset.multiset" and "FinFun.finfun".
   756   - Improved efficiency of "destroy_constrs" optimization.
   757   - Fixed soundness bugs related to "destroy_constrs" optimization and
   758     record getters.
   759   - Fixed soundness bug related to higher-order constructors.
   760   - Fixed soundness bug when "full_descrs" is enabled.
   761   - Improved precision of set constructs.
   762   - Added "atoms" option.
   763   - Added cache to speed up repeated Kodkod invocations on the same
   764     problems.
   765   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
   766     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
   767     "SAT4J_Light".  INCOMPATIBILITY.
   768   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
   769     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
   770   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
   771 
   772 * Method "induct" now takes instantiations of the form t, where t is not
   773   a variable, as a shorthand for "x == t", where x is a fresh variable.
   774   If this is not intended, t has to be enclosed in parentheses.
   775   By default, the equalities generated by definitional instantiations
   776   are pre-simplified, which may cause parameters of inductive cases
   777   to disappear, or may even delete some of the inductive cases.
   778   Use "induct (no_simp)" instead of "induct" to restore the old
   779   behaviour. The (no_simp) option is also understood by the "cases"
   780   and "nominal_induct" methods, which now perform pre-simplification, too.
   781   INCOMPATIBILITY.
   782 
   783 
   784 *** HOLCF ***
   785 
   786 * Variable names in lemmas generated by the domain package have
   787 changed; the naming scheme is now consistent with the HOL datatype
   788 package.  Some proof scripts may be affected, INCOMPATIBILITY.
   789 
   790 * The domain package no longer defines the function "foo_copy" for
   791 recursive domain "foo".  The reach lemma is now stated directly in
   792 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
   793 be reformulated in terms of "foo_take", INCOMPATIBILITY.
   794 
   795 * Most definedness lemmas generated by the domain package (previously
   796 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
   797 like "foo$x = UU <-> x = UU", which works better as a simp rule.
   798 Proofs that used definedness lemmas as intro rules may break,
   799 potential INCOMPATIBILITY.
   800 
   801 * Induction and casedist rules generated by the domain package now
   802 declare proper case_names (one called "bottom", and one named for each
   803 constructor).  INCOMPATIBILITY.
   804 
   805 * For mutually-recursive domains, separate "reach" and "take_lemma"
   806 rules are generated for each domain, INCOMPATIBILITY.
   807 
   808   foo_bar.reach       ~> foo.reach  bar.reach
   809   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
   810 
   811 * Some lemmas generated by the domain package have been renamed for
   812 consistency with the datatype package, INCOMPATIBILITY.
   813 
   814   foo.ind        ~> foo.induct
   815   foo.finite_ind ~> foo.finite_induct
   816   foo.coind      ~> foo.coinduct
   817   foo.casedist   ~> foo.exhaust
   818   foo.exhaust    ~> foo.nchotomy
   819 
   820 * For consistency with other definition packages, the fixrec package
   821 now generates qualified theorem names, INCOMPATIBILITY.
   822 
   823   foo_simps  ~> foo.simps
   824   foo_unfold ~> foo.unfold
   825   foo_induct ~> foo.induct
   826 
   827 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
   828 method and internal fixrec proofs now use the default simpset instead.
   829 INCOMPATIBILITY.
   830 
   831 * The "contlub" predicate has been removed.  Proof scripts should use
   832 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
   833 
   834 * The "admw" predicate has been removed, INCOMPATIBILITY.
   835 
   836 * The constants cpair, cfst, and csnd have been removed in favor of
   837 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
   838 
   839 
   840 *** ML ***
   841 
   842 * Antiquotations for basic formal entities:
   843 
   844     @{class NAME}         -- type class
   845     @{class_syntax NAME}  -- syntax representation of the above
   846 
   847     @{type_name NAME}     -- logical type
   848     @{type_abbrev NAME}   -- type abbreviation
   849     @{nonterminal NAME}   -- type of concrete syntactic category
   850     @{type_syntax NAME}   -- syntax representation of any of the above
   851 
   852     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
   853     @{const_abbrev NAME}  -- abbreviated constant
   854     @{const_syntax NAME}  -- syntax representation of any of the above
   855 
   856 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
   857 syntax constant (cf. 'syntax' command).
   858 
   859 * Antiquotation @{make_string} inlines a function to print arbitrary
   860 values similar to the ML toplevel.  The result is compiler dependent
   861 and may fall back on "?" in certain situations.
   862 
   863 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
   864 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
   865 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
   866 not work with the asynchronous Isar document model.
   867 
   868 * Configuration options now admit dynamic default values, depending on
   869 the context or even global references.
   870 
   871 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
   872 uses an efficient external library if available (for Poly/ML).
   873 
   874 * Renamed some important ML structures, while keeping the old names
   875 for some time as aliases within the structure Legacy:
   876 
   877   OuterKeyword  ~>  Keyword
   878   OuterLex      ~>  Token
   879   OuterParse    ~>  Parse
   880   OuterSyntax   ~>  Outer_Syntax
   881   PrintMode     ~>  Print_Mode
   882   SpecParse     ~>  Parse_Spec
   883   ThyInfo       ~>  Thy_Info
   884   ThyLoad       ~>  Thy_Load
   885   ThyOutput     ~>  Thy_Output
   886   TypeInfer     ~>  Type_Infer
   887 
   888 Note that "open Legacy" simplifies porting of sources, but forgetting
   889 to remove it again will complicate porting again in the future.
   890 
   891 * Most operations that refer to a global context are named
   892 accordingly, e.g. Simplifier.global_context or
   893 ProofContext.init_global.  There are some situations where a global
   894 context actually works, but under normal circumstances one needs to
   895 pass the proper local context through the code!
   896 
   897 * Discontinued old TheoryDataFun with its copy/init operation -- data
   898 needs to be pure.  Functor Theory_Data_PP retains the traditional
   899 Pretty.pp argument to merge, which is absent in the standard
   900 Theory_Data version.
   901 
   902 * Sorts.certify_sort and derived "cert" operations for types and terms
   903 no longer minimize sorts.  Thus certification at the boundary of the
   904 inference kernel becomes invariant under addition of class relations,
   905 which is an important monotonicity principle.  Sorts are now minimized
   906 in the syntax layer only, at the boundary between the end-user and the
   907 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
   908 explicitly in rare situations.
   909 
   910 * Renamed old-style Drule.standard to Drule.export_without_context, to
   911 emphasize that this is in no way a standard operation.
   912 INCOMPATIBILITY.
   913 
   914 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
   915 usual for resolution.  Rare INCOMPATIBILITY.
   916 
   917 * Renamed varify/unvarify operations to varify_global/unvarify_global
   918 to emphasize that these only work in a global situation (which is
   919 quite rare).
   920 
   921 * Curried take and drop in library.ML; negative length is interpreted
   922 as infinity (as in chop).  Subtle INCOMPATIBILITY.
   923 
   924 * Proof terms: type substitutions on proof constants now use canonical
   925 order of type variables.  INCOMPATIBILITY for tools working with proof
   926 terms.
   927 
   928 * Raw axioms/defs may no longer carry sort constraints, and raw defs
   929 may no longer carry premises.  User-level specifications are
   930 transformed accordingly by Thm.add_axiom/add_def.
   931 
   932 
   933 *** System ***
   934 
   935 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
   936 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
   937 proof terms are enabled unconditionally in the new HOL-Proofs image.
   938 
   939 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
   940 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
   941 respectively.
   942 
   943 * Old lib/scripts/polyml-platform is superseded by the
   944 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
   945 variant, even on a 64 bit machine.  The following example setting
   946 prefers 64 bit if available:
   947 
   948   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
   949 
   950 * The preliminary Isabelle/jEdit application demonstrates the emerging
   951 Isabelle/Scala layer for advanced prover interaction and integration.
   952 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
   953 component.
   954 
   955 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
   956 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
   957 similar to the default assignment of the document preparation system
   958 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
   959 provides some operations for direct access to the font without asking
   960 the user for manual installation.
   961 
   962 
   963 
   964 New in Isabelle2009-1 (December 2009)
   965 -------------------------------------
   966 
   967 *** General ***
   968 
   969 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
   970 one backslash should be used, even in ML sources.
   971 
   972 
   973 *** Pure ***
   974 
   975 * Locale interpretation propagates mixins along the locale hierarchy.
   976 The currently only available mixins are the equations used to map
   977 local definitions to terms of the target domain of an interpretation.
   978 
   979 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
   980 loc" to print all interpretations of locale "loc" in the theory.
   981 Interpretations in proofs are not shown.
   982 
   983 * Thoroughly revised locales tutorial.  New section on conditional
   984 interpretation.
   985 
   986 * On instantiation of classes, remaining undefined class parameters
   987 are formally declared.  INCOMPATIBILITY.
   988 
   989 
   990 *** Document preparation ***
   991 
   992 * New generalized style concept for printing terms: @{foo (style) ...}
   993 instead of @{foo_style style ...}  (old form is still retained for
   994 backward compatibility).  Styles can be also applied for
   995 antiquotations prop, term_type and typeof.
   996 
   997 
   998 *** HOL ***
   999 
  1000 * New proof method "smt" for a combination of first-order logic with
  1001 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1002 fixed-size bitvectors; there is also basic support for higher-order
  1003 features (esp. lambda abstractions).  It is an incomplete decision
  1004 procedure based on external SMT solvers using the oracle mechanism;
  1005 for the SMT solver Z3, this method is proof-producing.  Certificates
  1006 are provided to avoid calling the external solvers solely for
  1007 re-checking proofs.  Due to a remote SMT service there is no need for
  1008 installing SMT solvers locally.  See src/HOL/SMT.
  1009 
  1010 * New commands to load and prove verification conditions generated by
  1011 the Boogie program verifier or derived systems (e.g. the Verifying C
  1012 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1013 
  1014 * New counterexample generator tool 'nitpick' based on the Kodkod
  1015 relational model finder.  See src/HOL/Tools/Nitpick and
  1016 src/HOL/Nitpick_Examples.
  1017 
  1018 * New commands 'code_pred' and 'values' to invoke the predicate
  1019 compiler and to enumerate values of inductive predicates.
  1020 
  1021 * A tabled implementation of the reflexive transitive closure.
  1022 
  1023 * New implementation of quickcheck uses generic code generator;
  1024 default generators are provided for all suitable HOL types, records
  1025 and datatypes.  Old quickcheck can be re-activated importing theory
  1026 Library/SML_Quickcheck.
  1027 
  1028 * New testing tool Mirabelle for automated proof tools.  Applies
  1029 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1030 every proof step in a theory.  To be used in batch mode via the
  1031 "mirabelle" utility.
  1032 
  1033 * New proof method "sos" (sum of squares) for nonlinear real
  1034 arithmetic (originally due to John Harison). It requires theory
  1035 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1036 works well in practice on quantifier-free real arithmetic with +, -,
  1037 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1038 inequalities between polynomials.  It makes use of external
  1039 semidefinite programming solvers.  Method "sos" generates a
  1040 certificate that can be pasted into the proof thus avoiding the need
  1041 to call an external tool every time the proof is checked.  See
  1042 src/HOL/Library/Sum_Of_Squares.
  1043 
  1044 * New method "linarith" invokes existing linear arithmetic decision
  1045 procedure only.
  1046 
  1047 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1048 
  1049 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1050 Causes full type information to be output to the ATPs.  This slows
  1051 ATPs down considerably but eliminates a source of unsound "proofs"
  1052 that fail later.
  1053 
  1054 * New method "metisFT": A version of metis that uses full type
  1055 information in order to avoid failures of proof reconstruction.
  1056 
  1057 * New evaluator "approximate" approximates an real valued term using
  1058 the same method as the approximation method.
  1059 
  1060 * Method "approximate" now supports arithmetic expressions as
  1061 boundaries of intervals and implements interval splitting and Taylor
  1062 series expansion.
  1063 
  1064 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1065 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1066 
  1067 * New theory SupInf of the supremum and infimum operators for sets of
  1068 reals.
  1069 
  1070 * New theory Probability, which contains a development of measure
  1071 theory, eventually leading to Lebesgue integration and probability.
  1072 
  1073 * Extended Multivariate Analysis to include derivation and Brouwer's
  1074 fixpoint theorem.
  1075 
  1076 * Reorganization of number theory, INCOMPATIBILITY:
  1077   - new number theory development for nat and int, in theories Divides
  1078     and GCD as well as in new session Number_Theory
  1079   - some constants and facts now suffixed with _nat and _int
  1080     accordingly
  1081   - former session NumberTheory now named Old_Number_Theory, including
  1082     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1083   - moved theory Pocklington from src/HOL/Library to
  1084     src/HOL/Old_Number_Theory
  1085 
  1086 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1087 lcm of finite and infinite sets. It is shown that they form a complete
  1088 lattice.
  1089 
  1090 * Class semiring_div requires superclass no_zero_divisors and proof of
  1091 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1092 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1093 generalized to class semiring_div, subsuming former theorems
  1094 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1095 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1096 INCOMPATIBILITY.
  1097 
  1098 * Refinements to lattice classes and sets:
  1099   - less default intro/elim rules in locale variant, more default
  1100     intro/elim rules in class variant: more uniformity
  1101   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1102     le_inf_iff
  1103   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1104     sup_aci)
  1105   - renamed ACI to inf_sup_aci
  1106   - new class "boolean_algebra"
  1107   - class "complete_lattice" moved to separate theory
  1108     "Complete_Lattice"; corresponding constants (and abbreviations)
  1109     renamed and with authentic syntax:
  1110     Set.Inf ~>    Complete_Lattice.Inf
  1111     Set.Sup ~>    Complete_Lattice.Sup
  1112     Set.INFI ~>   Complete_Lattice.INFI
  1113     Set.SUPR ~>   Complete_Lattice.SUPR
  1114     Set.Inter ~>  Complete_Lattice.Inter
  1115     Set.Union ~>  Complete_Lattice.Union
  1116     Set.INTER ~>  Complete_Lattice.INTER
  1117     Set.UNION ~>  Complete_Lattice.UNION
  1118   - authentic syntax for
  1119     Set.Pow
  1120     Set.image
  1121   - mere abbreviations:
  1122     Set.empty               (for bot)
  1123     Set.UNIV                (for top)
  1124     Set.inter               (for inf, formerly Set.Int)
  1125     Set.union               (for sup, formerly Set.Un)
  1126     Complete_Lattice.Inter  (for Inf)
  1127     Complete_Lattice.Union  (for Sup)
  1128     Complete_Lattice.INTER  (for INFI)
  1129     Complete_Lattice.UNION  (for SUPR)
  1130   - object-logic definitions as far as appropriate
  1131 
  1132 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1133 Un_subset_iff are explicitly deleted as default simp rules; then also
  1134 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1135 deleted to achieve the desired effect.
  1136 
  1137 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1138 rules by default any longer; the same applies to min_max.inf_absorb1
  1139 etc.  INCOMPATIBILITY.
  1140 
  1141 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1142 pred_set_conv by default.  INCOMPATIBILITY.
  1143 
  1144 * Power operations on relations and functions are now one dedicated
  1145 constant "compow" with infix syntax "^^".  Power operation on
  1146 multiplicative monoids retains syntax "^" and is now defined generic
  1147 in class power.  INCOMPATIBILITY.
  1148 
  1149 * Relation composition "R O S" now has a more standard argument order:
  1150 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1151 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1152 break, since the O_assoc rule was not rewritten like this.  Fix using
  1153 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1154 
  1155 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1156 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1157 INCOMPATIBILITY.
  1158 
  1159 * Most rules produced by inductive and datatype package have mandatory
  1160 prefixes.  INCOMPATIBILITY.
  1161 
  1162 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1163 the attribute of the same name.  Each of the theorems in the list
  1164 DERIV_intros assumes composition with an additional function and
  1165 matches a variable to the derivative, which has to be solved by the
  1166 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1167 of most elementary terms.  Former Maclauren.DERIV_tac and
  1168 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1169 INCOMPATIBILITY.
  1170 
  1171 * Code generator attributes follow the usual underscore convention:
  1172     code_unfold     replaces    code unfold
  1173     code_post       replaces    code post
  1174     etc.
  1175   INCOMPATIBILITY.
  1176 
  1177 * Renamed methods:
  1178     sizechange -> size_change
  1179     induct_scheme -> induction_schema
  1180   INCOMPATIBILITY.
  1181 
  1182 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1183 INCOMPATIBILITY, use "undefined" directly.
  1184 
  1185 * Renamed theorems:
  1186     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1187     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1188     Suc_plus1 -> Suc_eq_plus1
  1189     *anti_sym -> *antisym*
  1190     vector_less_eq_def -> vector_le_def
  1191   INCOMPATIBILITY.
  1192 
  1193 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1194 INCOMPATIBILITY.
  1195 
  1196 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1197 INCOMPATIBILITY.
  1198 
  1199 
  1200 *** HOLCF ***
  1201 
  1202 * Theory Representable defines a class "rep" of domains that are
  1203 representable (via an ep-pair) in the universal domain type "udom".
  1204 Instances are provided for all type constructors defined in HOLCF.
  1205 
  1206 * The 'new_domain' command is a purely definitional version of the
  1207 domain package, for representable domains.  Syntax is identical to the
  1208 old domain package.  The 'new_domain' package also supports indirect
  1209 recursion using previously-defined type constructors.  See
  1210 src/HOLCF/ex/New_Domain.thy for examples.
  1211 
  1212 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1213 on the left-hand side of an equation, and then performs
  1214 simplification.  Rewriting is done using rules declared with the
  1215 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1216 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1217 
  1218 * The pattern-match compiler in 'fixrec' can now handle constructors
  1219 with HOL function types.  Pattern-match combinators for the Pair
  1220 constructor are pre-configured.
  1221 
  1222 * The 'fixrec' package now produces better fixed-point induction rules
  1223 for mutually-recursive definitions:  Induction rules have conclusions
  1224 of the form "P foo bar" instead of "P <foo, bar>".
  1225 
  1226 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1227 been renamed to "below".  The name "below" now replaces "less" in many
  1228 theorem names.  (Legacy theorem names using "less" are still supported
  1229 as well.)
  1230 
  1231 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1232 patterns can be used to generate strictness rules, or to make
  1233 functions more strict (much like the bang-patterns supported by the
  1234 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1235 examples.
  1236 
  1237 
  1238 *** ML ***
  1239 
  1240 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1241 errors and run-time exceptions, including detailed source positions.
  1242 
  1243 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1244 identified entries, with some additional information such as source
  1245 position, logical grouping etc.
  1246 
  1247 * Theory and context data is now introduced by the simplified and
  1248 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1249 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1250 copy operation) is still available for some time.
  1251 
  1252 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1253 provides a high-level programming interface to synchronized state
  1254 variables with atomic update.  This works via pure function
  1255 application within a critical section -- its runtime should be as
  1256 short as possible; beware of deadlocks if critical code is nested,
  1257 either directly or indirectly via other synchronized variables!
  1258 
  1259 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1260 wraps raw ML references, explicitly indicating their non-thread-safe
  1261 behaviour.  The Isar toplevel keeps this structure open, to
  1262 accommodate Proof General as well as quick and dirty interactive
  1263 experiments with references.
  1264 
  1265 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1266 parallel tactical reasoning.
  1267 
  1268 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1269 are similar to SUBPROOF, but are slightly more flexible: only the
  1270 specified parts of the subgoal are imported into the context, and the
  1271 body tactic may introduce new subgoals and schematic variables.
  1272 
  1273 * Old tactical METAHYPS, which does not observe the proof context, has
  1274 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1275 or Subgoal.FOCUS etc.
  1276 
  1277 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1278 functors have their own ML name space there is no point to mark them
  1279 separately.)  Minor INCOMPATIBILITY.
  1280 
  1281 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1282 
  1283 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1284 INCOMPATIBILITY.
  1285 
  1286 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1287 mode, which avoids critical setmp.
  1288 
  1289 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1290 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1291 Attrib/Method.setup introduced in Isabelle2009.
  1292 
  1293 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1294 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1295 last resort.  INCOMPATIBILITY.
  1296 
  1297 * Display.pretty_thm now requires a proper context (cf. former
  1298 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1299 or even Display.pretty_thm_without_context as last resort.
  1300 INCOMPATIBILITY.
  1301 
  1302 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1303 Syntax.pretty_typ/term directly, preferably with proper context
  1304 instead of global theory.
  1305 
  1306 
  1307 *** System ***
  1308 
  1309 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1310 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1311 usedir option -q.
  1312 
  1313 * Support for additional "Isabelle components" via etc/components, see
  1314 also the system manual.
  1315 
  1316 * The isabelle makeall tool now operates on all components with
  1317 IsaMakefile, not just hardwired "logics".
  1318 
  1319 * Removed "compress" option from isabelle-process and isabelle usedir;
  1320 this is always enabled.
  1321 
  1322 * Discontinued support for Poly/ML 4.x versions.
  1323 
  1324 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  1325 on a given logic image.  This requires the lighttpd webserver and is
  1326 currently supported on Linux only.
  1327 
  1328 
  1329 
  1330 New in Isabelle2009 (April 2009)
  1331 --------------------------------
  1332 
  1333 *** General ***
  1334 
  1335 * Simplified main Isabelle executables, with less surprises on
  1336 case-insensitive file-systems (such as Mac OS).
  1337 
  1338   - The main Isabelle tool wrapper is now called "isabelle" instead of
  1339     "isatool."
  1340 
  1341   - The former "isabelle" alias for "isabelle-process" has been
  1342     removed (should rarely occur to regular users).
  1343 
  1344   - The former "isabelle-interface" and its alias "Isabelle" have been
  1345     removed (interfaces are now regular Isabelle tools).
  1346 
  1347 Within scripts and make files, the Isabelle environment variables
  1348 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  1349 respectively.  (The latter are still available as legacy feature.)
  1350 
  1351 The old isabelle-interface wrapper could react in confusing ways if
  1352 the interface was uninstalled or changed otherwise.  Individual
  1353 interface tool configuration is now more explicit, see also the
  1354 Isabelle system manual.  In particular, Proof General is now available
  1355 via "isabelle emacs".
  1356 
  1357 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  1358 purge installed copies of Isabelle executables and re-run "isabelle
  1359 install -p ...", or use symlinks.
  1360 
  1361 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  1362 old ~/isabelle, which was slightly non-standard and apt to cause
  1363 surprises on case-insensitive file-systems (such as Mac OS).
  1364 
  1365 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  1366 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  1367 care is required when using older releases of Isabelle.  Note that
  1368 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  1369 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  1370 
  1371 * Proofs of fully specified statements are run in parallel on
  1372 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  1373 a regular 4-core machine, if the initial heap space is made reasonably
  1374 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  1375 
  1376 * The main reference manuals ("isar-ref", "implementation", and
  1377 "system") have been updated and extended.  Formally checked references
  1378 as hyperlinks are now available uniformly.
  1379 
  1380 
  1381 *** Pure ***
  1382 
  1383 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  1384 respects.  The most important changes are listed below.  See the
  1385 Tutorial on Locales ("locales" manual) for details.
  1386 
  1387 - In locale expressions, instantiation replaces renaming.  Parameters
  1388 must be declared in a for clause.  To aid compatibility with previous
  1389 parameter inheritance, in locale declarations, parameters that are not
  1390 'touched' (instantiation position "_" or omitted) are implicitly added
  1391 with their syntax at the beginning of the for clause.
  1392 
  1393 - Syntax from abbreviations and definitions in locales is available in
  1394 locale expressions and context elements.  The latter is particularly
  1395 useful in locale declarations.
  1396 
  1397 - More flexible mechanisms to qualify names generated by locale
  1398 expressions.  Qualifiers (prefixes) may be specified in locale
  1399 expressions, and can be marked as mandatory (syntax: "name!:") or
  1400 optional (syntax "name?:").  The default depends for plain "name:"
  1401 depends on the situation where a locale expression is used: in
  1402 commands 'locale' and 'sublocale' prefixes are optional, in
  1403 'interpretation' and 'interpret' prefixes are mandatory.  The old
  1404 implicit qualifiers derived from the parameter names of a locale are
  1405 no longer generated.
  1406 
  1407 - Command "sublocale l < e" replaces "interpretation l < e".  The
  1408 instantiation clause in "interpretation" and "interpret" (square
  1409 brackets) is no longer available.  Use locale expressions.
  1410 
  1411 - When converting proof scripts, mandatory qualifiers in
  1412 'interpretation' and 'interpret' should be retained by default, even
  1413 if this is an INCOMPATIBILITY compared to former behavior.  In the
  1414 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  1415 in locale expressions range over a single locale instance only.
  1416 
  1417 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  1418 In existing theorem specifications replace the includes element by the
  1419 respective context elements of the included locale, omitting those
  1420 that are already present in the theorem specification.  Multiple
  1421 assume elements of a locale should be replaced by a single one
  1422 involving the locale predicate.  In the proof body, declarations (most
  1423 notably theorems) may be regained by interpreting the respective
  1424 locales in the proof context as required (command "interpret").
  1425 
  1426 If using "includes" in replacement of a target solely because the
  1427 parameter types in the theorem are not as general as in the target,
  1428 consider declaring a new locale with additional type constraints on
  1429 the parameters (context element "constrains").
  1430 
  1431 - Discontinued "locale (open)".  INCOMPATIBILITY.
  1432 
  1433 - Locale interpretation commands no longer attempt to simplify goal.
  1434 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  1435 methods intro_locales and unfold_locales to clarify.
  1436 
  1437 - Locale interpretation commands no longer accept interpretation
  1438 attributes.  INCOMPATIBILITY.
  1439 
  1440 * Class declaration: so-called "base sort" must not be given in import
  1441 list any longer, but is inferred from the specification.  Particularly
  1442 in HOL, write
  1443 
  1444     class foo = ...
  1445 
  1446 instead of
  1447 
  1448     class foo = type + ...
  1449 
  1450 * Class target: global versions of theorems stemming do not carry a
  1451 parameter prefix any longer.  INCOMPATIBILITY.
  1452 
  1453 * Class 'instance' command no longer accepts attached definitions.
  1454 INCOMPATIBILITY, use proper 'instantiation' target instead.
  1455 
  1456 * Recovered hiding of consts, which was accidentally broken in
  1457 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  1458 makes c inaccessible; consider using ``hide (open) const c'' instead.
  1459 
  1460 * Slightly more coherent Pure syntax, with updated documentation in
  1461 isar-ref manual.  Removed locales meta_term_syntax and
  1462 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  1463 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  1464 directly in regular applications.
  1465 
  1466 * There is a new syntactic category "float_const" for signed decimal
  1467 fractions (e.g. 123.45 or -123.45).
  1468 
  1469 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  1470 interface with 'setup' command instead.
  1471 
  1472 * Command 'local_setup' is similar to 'setup', but operates on a local
  1473 theory context.
  1474 
  1475 * The 'axiomatization' command now only works within a global theory
  1476 context.  INCOMPATIBILITY.
  1477 
  1478 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  1479 hypotheses.  Sorts required in the course of reasoning need to be
  1480 covered by the constraints in the initial statement, completed by the
  1481 type instance information of the background theory.  Non-trivial sort
  1482 hypotheses, which rarely occur in practice, may be specified via
  1483 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  1484 
  1485   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  1486 
  1487 The result contains an implicit sort hypotheses as before --
  1488 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  1489 normalization.
  1490 
  1491 * Generalized Isar history, with support for linear undo, direct state
  1492 addressing etc.
  1493 
  1494 * Changed defaults for unify configuration options:
  1495 
  1496   unify_trace_bound = 50 (formerly 25)
  1497   unify_search_bound = 60 (formerly 30)
  1498 
  1499 * Different bookkeeping for code equations (INCOMPATIBILITY):
  1500 
  1501   a) On theory merge, the last set of code equations for a particular
  1502      constant is taken (in accordance with the policy applied by other
  1503      parts of the code generator framework).
  1504 
  1505   b) Code equations stemming from explicit declarations (e.g. code
  1506      attribute) gain priority over default code equations stemming
  1507      from definition, primrec, fun etc.
  1508 
  1509 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  1510 
  1511 * Unified theorem tables for both code generators.  Thus [code
  1512 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  1513 
  1514 * Command 'find_consts' searches for constants based on type and name
  1515 patterns, e.g.
  1516 
  1517     find_consts "_ => bool"
  1518 
  1519 By default, matching is against subtypes, but it may be restricted to
  1520 the whole type.  Searching by name is possible.  Multiple queries are
  1521 conjunctive and queries may be negated by prefixing them with a
  1522 hyphen:
  1523 
  1524     find_consts strict: "_ => bool" name: "Int" -"int => int"
  1525 
  1526 * New 'find_theorems' criterion "solves" matches theorems that
  1527 directly solve the current goal (modulo higher-order unification).
  1528 
  1529 * Auto solve feature for main theorem statements: whenever a new goal
  1530 is stated, "find_theorems solves" is called; any theorems that could
  1531 solve the lemma directly are listed as part of the goal state.
  1532 Cf. associated options in Proof General Isabelle settings menu,
  1533 enabled by default, with reasonable timeout for pathological cases of
  1534 higher-order unification.
  1535 
  1536 
  1537 *** Document preparation ***
  1538 
  1539 * Antiquotation @{lemma} now imitates a regular terminal proof,
  1540 demanding keyword 'by' and supporting the full method expression
  1541 syntax just like the Isar command 'by'.
  1542 
  1543 
  1544 *** HOL ***
  1545 
  1546 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  1547 points Main and Complex_Main remain as before.
  1548 
  1549 * Logic image HOL-Plain provides a minimal HOL with the most important
  1550 tools available (inductive, datatype, primrec, ...).  This facilitates
  1551 experimentation and tool development.  Note that user applications
  1552 (and library theories) should never refer to anything below theory
  1553 Main, as before.
  1554 
  1555 * Logic image HOL-Main stops at theory Main, and thus facilitates
  1556 experimentation due to shorter build times.
  1557 
  1558 * Logic image HOL-NSA contains theories of nonstandard analysis which
  1559 were previously part of former HOL-Complex.  Entry point Hyperreal
  1560 remains valid, but theories formerly using Complex_Main should now use
  1561 new entry point Hypercomplex.
  1562 
  1563 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  1564 Posix processes.  Avoids potentially expensive forking of the ML
  1565 process.  New thread-based implementation also works on non-Unix
  1566 platforms (Cygwin).  Provers are no longer hardwired, but defined
  1567 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  1568 commands are covered in the isar-ref manual.
  1569 
  1570 * Wrapper scripts for remote SystemOnTPTP service allows to use
  1571 sledgehammer without local ATP installation (Vampire etc.). Other
  1572 provers may be included via suitable ML wrappers, see also
  1573 src/HOL/ATP_Linkup.thy.
  1574 
  1575 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  1576 menu.
  1577 
  1578 * The metis method no longer fails because the theorem is too trivial
  1579 (contains the empty clause).
  1580 
  1581 * The metis method now fails in the usual manner, rather than raising
  1582 an exception, if it determines that it cannot prove the theorem.
  1583 
  1584 * Method "coherent" implements a prover for coherent logic (see also
  1585 src/Tools/coherent.ML).
  1586 
  1587 * Constants "undefined" and "default" replace "arbitrary".  Usually
  1588 "undefined" is the right choice to replace "arbitrary", though
  1589 logically there is no difference.  INCOMPATIBILITY.
  1590 
  1591 * Command "value" now integrates different evaluation mechanisms.  The
  1592 result of the first successful evaluation mechanism is printed.  In
  1593 square brackets a particular named evaluation mechanisms may be
  1594 specified (currently, [SML], [code] or [nbe]).  See further
  1595 src/HOL/ex/Eval_Examples.thy.
  1596 
  1597 * Normalization by evaluation now allows non-leftlinear equations.
  1598 Declare with attribute [code nbe].
  1599 
  1600 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  1601 as the structured Isar versions "cases" and "induct", cf. the
  1602 corresponding "cases" and "induct" attributes.  Mutual induction rules
  1603 are now presented as a list of individual projections
  1604 (e.g. foo_bar.inducts for types foo and bar); the old format with
  1605 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  1606 rare situations a different rule is selected --- notably nested tuple
  1607 elimination instead of former prod.exhaust: use explicit (case_tac t
  1608 rule: prod.exhaust) here.
  1609 
  1610 * Attributes "cases", "induct", "coinduct" support "del" option.
  1611 
  1612 * Removed fact "case_split_thm", which duplicates "case_split".
  1613 
  1614 * The option datatype has been moved to a new theory Option.  Renamed
  1615 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  1616 
  1617 * New predicate "strict_mono" classifies strict functions on partial
  1618 orders.  With strict functions on linear orders, reasoning about
  1619 (in)equalities is facilitated by theorems "strict_mono_eq",
  1620 "strict_mono_less_eq" and "strict_mono_less".
  1621 
  1622 * Some set operations are now proper qualified constants with
  1623 authentic syntax.  INCOMPATIBILITY:
  1624 
  1625     op Int ~>   Set.Int
  1626     op Un ~>    Set.Un
  1627     INTER ~>    Set.INTER
  1628     UNION ~>    Set.UNION
  1629     Inter ~>    Set.Inter
  1630     Union ~>    Set.Union
  1631     {} ~>       Set.empty
  1632     UNIV ~>     Set.UNIV
  1633 
  1634 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  1635 theory Set.
  1636 
  1637 * Auxiliary class "itself" has disappeared -- classes without any
  1638 parameter are treated as expected by the 'class' command.
  1639 
  1640 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  1641 
  1642 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  1643 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  1644 
  1645 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  1646 method "approximation".  It proves formulas on real values by using
  1647 interval arithmetic.  In the formulas are also the transcendental
  1648 functions sin, cos, tan, atan, ln, exp and the constant pi are
  1649 allowed. For examples see
  1650 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  1651 
  1652 * Theory "Reflection" now resides in HOL/Library.
  1653 
  1654 * Entry point to Word library now simply named "Word".
  1655 INCOMPATIBILITY.
  1656 
  1657 * Made source layout more coherent with logical distribution
  1658 structure:
  1659 
  1660     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  1661     src/HOL/Library/Code_Message.thy ~> src/HOL/
  1662     src/HOL/Library/GCD.thy ~> src/HOL/
  1663     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  1664     src/HOL/Library/Parity.thy ~> src/HOL/
  1665     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  1666     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  1667     src/HOL/Real/Lubs.thy ~> src/HOL/
  1668     src/HOL/Real/PReal.thy ~> src/HOL/
  1669     src/HOL/Real/Rational.thy ~> src/HOL/
  1670     src/HOL/Real/RComplete.thy ~> src/HOL/
  1671     src/HOL/Real/RealDef.thy ~> src/HOL/
  1672     src/HOL/Real/RealPow.thy ~> src/HOL/
  1673     src/HOL/Real/Real.thy ~> src/HOL/
  1674     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  1675     src/HOL/Complex/Complex.thy ~> src/HOL/
  1676     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  1677     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  1678     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  1679     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  1680     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  1681     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  1682     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  1683     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  1684     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  1685     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  1686     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  1687     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  1688     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  1689     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  1690     src/HOL/Real/Float ~> src/HOL/Library/
  1691     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  1692     src/HOL/Real/RealVector.thy ~> src/HOL/
  1693 
  1694     src/HOL/arith_data.ML ~> src/HOL/Tools
  1695     src/HOL/hologic.ML ~> src/HOL/Tools
  1696     src/HOL/simpdata.ML ~> src/HOL/Tools
  1697     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  1698     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  1699     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  1700     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  1701     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  1702     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  1703     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  1704 
  1705     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  1706     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  1707     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  1708     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  1709     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  1710     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  1711 
  1712 * If methods "eval" and "evaluation" encounter a structured proof
  1713 state with !!/==>, only the conclusion is evaluated to True (if
  1714 possible), avoiding strange error messages.
  1715 
  1716 * Method "sizechange" automates termination proofs using (a
  1717 modification of) the size-change principle.  Requires SAT solver.  See
  1718 src/HOL/ex/Termination.thy for examples.
  1719 
  1720 * Simplifier: simproc for let expressions now unfolds if bound
  1721 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  1722 
  1723 * Method "arith": Linear arithmetic now ignores all inequalities when
  1724 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  1725 
  1726 * New attribute "arith" for facts that should always be used
  1727 automatically by arithmetic. It is intended to be used locally in
  1728 proofs, e.g.
  1729 
  1730   assumes [arith]: "x > 0"
  1731 
  1732 Global usage is discouraged because of possible performance impact.
  1733 
  1734 * New classes "top" and "bot" with corresponding operations "top" and
  1735 "bot" in theory Orderings; instantiation of class "complete_lattice"
  1736 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  1737 
  1738 * Changed definition lemma "less_fun_def" in order to provide an
  1739 instance for preorders on functions; use lemma "less_le" instead.
  1740 INCOMPATIBILITY.
  1741 
  1742 * Theory Orderings: class "wellorder" moved here, with explicit
  1743 induction rule "less_induct" as assumption.  For instantiation of
  1744 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  1745 INCOMPATIBILITY.
  1746 
  1747 * Theory Orderings: added class "preorder" as superclass of "order".
  1748 INCOMPATIBILITY: Instantiation proofs for order, linorder
  1749 etc. slightly changed.  Some theorems named order_class.* now named
  1750 preorder_class.*.
  1751 
  1752 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  1753 "diag" to "Id_on".
  1754 
  1755 * Theory Finite_Set: added a new fold combinator of type
  1756 
  1757   ('a => 'b => 'b) => 'b => 'a set => 'b
  1758 
  1759 Occasionally this is more convenient than the old fold combinator
  1760 which is now defined in terms of the new one and renamed to
  1761 fold_image.
  1762 
  1763 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  1764 and "ring_simps" have been replaced by "algebra_simps" (which can be
  1765 extended with further lemmas!).  At the moment both still exist but
  1766 the former will disappear at some point.
  1767 
  1768 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  1769 class recpower.  Type-specific simp rules for various recpower types
  1770 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  1771 
  1772 rat_power_0    -> power_0
  1773 rat_power_Suc  -> power_Suc
  1774 realpow_0      -> power_0
  1775 realpow_Suc    -> power_Suc
  1776 complexpow_0   -> power_0
  1777 complexpow_Suc -> power_Suc
  1778 power_poly_0   -> power_0
  1779 power_poly_Suc -> power_Suc
  1780 
  1781 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  1782 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  1783 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  1784 of lemmas from Divides has been generalized from nat to class
  1785 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  1786 renames resulting from duplicate elimination:
  1787 
  1788     dvd_def_mod ~>          dvd_eq_mod_eq_0
  1789     zero_dvd_iff ~>         dvd_0_left_iff
  1790     dvd_0 ~>                dvd_0_right
  1791     DIVISION_BY_ZERO_DIV ~> div_by_0
  1792     DIVISION_BY_ZERO_MOD ~> mod_by_0
  1793     mult_div ~>             div_mult_self2_is_id
  1794     mult_mod ~>             mod_mult_self2_is_0
  1795 
  1796 * Theory IntDiv: removed many lemmas that are instances of class-based
  1797 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  1798 rename old lemmas as follows:
  1799 
  1800 dvd_diff               -> nat_dvd_diff
  1801 dvd_zminus_iff         -> dvd_minus_iff
  1802 mod_add1_eq            -> mod_add_eq
  1803 mod_mult1_eq           -> mod_mult_right_eq
  1804 mod_mult1_eq'          -> mod_mult_left_eq
  1805 mod_mult_distrib_mod   -> mod_mult_eq
  1806 nat_mod_add_left_eq    -> mod_add_left_eq
  1807 nat_mod_add_right_eq   -> mod_add_right_eq
  1808 nat_mod_div_trivial    -> mod_div_trivial
  1809 nat_mod_mod_trivial    -> mod_mod_trivial
  1810 zdiv_zadd_self1        -> div_add_self1
  1811 zdiv_zadd_self2        -> div_add_self2
  1812 zdiv_zmult_self1       -> div_mult_self2_is_id
  1813 zdiv_zmult_self2       -> div_mult_self1_is_id
  1814 zdvd_triv_left         -> dvd_triv_left
  1815 zdvd_triv_right        -> dvd_triv_right
  1816 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  1817 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  1818 zmod_zadd_left_eq      -> mod_add_left_eq
  1819 zmod_zadd_right_eq     -> mod_add_right_eq
  1820 zmod_zadd_self1        -> mod_add_self1
  1821 zmod_zadd_self2        -> mod_add_self2
  1822 zmod_zadd1_eq          -> mod_add_eq
  1823 zmod_zdiff1_eq         -> mod_diff_eq
  1824 zmod_zdvd_zmod         -> mod_mod_cancel
  1825 zmod_zmod_cancel       -> mod_mod_cancel
  1826 zmod_zmult_self1       -> mod_mult_self2_is_0
  1827 zmod_zmult_self2       -> mod_mult_self1_is_0
  1828 zmod_1                 -> mod_by_1
  1829 zdiv_1                 -> div_by_1
  1830 zdvd_abs1              -> abs_dvd_iff
  1831 zdvd_abs2              -> dvd_abs_iff
  1832 zdvd_refl              -> dvd_refl
  1833 zdvd_trans             -> dvd_trans
  1834 zdvd_zadd              -> dvd_add
  1835 zdvd_zdiff             -> dvd_diff
  1836 zdvd_zminus_iff        -> dvd_minus_iff
  1837 zdvd_zminus2_iff       -> minus_dvd_iff
  1838 zdvd_zmultD            -> dvd_mult_right
  1839 zdvd_zmultD2           -> dvd_mult_left
  1840 zdvd_zmult_mono        -> mult_dvd_mono
  1841 zdvd_0_right           -> dvd_0_right
  1842 zdvd_0_left            -> dvd_0_left_iff
  1843 zdvd_1_left            -> one_dvd
  1844 zminus_dvd_iff         -> minus_dvd_iff
  1845 
  1846 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  1847 
  1848 * The real numbers offer decimal input syntax: 12.34 is translated
  1849 into 1234/10^2. This translation is not reversed upon output.
  1850 
  1851 * Theory Library/Polynomial defines an abstract type 'a poly of
  1852 univariate polynomials with coefficients of type 'a.  In addition to
  1853 the standard ring operations, it also supports div and mod.  Code
  1854 generation is also supported, using list-style constructors.
  1855 
  1856 * Theory Library/Inner_Product defines a class of real_inner for real
  1857 inner product spaces, with an overloaded operation inner :: 'a => 'a
  1858 => real.  Class real_inner is a subclass of real_normed_vector from
  1859 theory RealVector.
  1860 
  1861 * Theory Library/Product_Vector provides instances for the product
  1862 type 'a * 'b of several classes from RealVector and Inner_Product.
  1863 Definitions of addition, subtraction, scalar multiplication, norms,
  1864 and inner products are included.
  1865 
  1866 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  1867 addition to the field operations, numerals and case syntax are also
  1868 supported.
  1869 
  1870 * Theory Library/Diagonalize provides constructive version of Cantor's
  1871 first diagonalization argument.
  1872 
  1873 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  1874 zlcm (for int); carried together from various gcd/lcm developements in
  1875 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  1876 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  1877 may recover tupled syntax as follows:
  1878 
  1879     hide (open) const gcd
  1880     abbreviation gcd where
  1881       "gcd == (%(a, b). GCD.gcd a b)"
  1882     notation (output)
  1883       GCD.gcd ("gcd '(_, _')")
  1884 
  1885 The same works for lcm, zgcd, zlcm.
  1886 
  1887 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  1888 instantiations for algebraic structures.  Removed some duplicate
  1889 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  1890 
  1891 * ML antiquotation @{code} takes a constant as argument and generates
  1892 corresponding code in background and inserts name of the corresponding
  1893 resulting ML value/function/datatype constructor binding in place.
  1894 All occurrences of @{code} with a single ML block are generated
  1895 simultaneously.  Provides a generic and safe interface for
  1896 instrumentalizing code generation.  See
  1897 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  1898 In future you ought to refrain from ad-hoc compiling generated SML
  1899 code on the ML toplevel.  Note that (for technical reasons) @{code}
  1900 cannot refer to constants for which user-defined serializations are
  1901 set.  Refer to the corresponding ML counterpart directly in that
  1902 cases.
  1903 
  1904 * Command 'rep_datatype': instead of theorem names the command now
  1905 takes a list of terms denoting the constructors of the type to be
  1906 represented as datatype.  The characteristic theorems have to be
  1907 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  1908 have disappeared in favour of existing ones:
  1909 
  1910     unit_induct                 ~> unit.induct
  1911     prod_induct                 ~> prod.induct
  1912     sum_induct                  ~> sum.induct
  1913     Suc_Suc_eq                  ~> nat.inject
  1914     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  1915 
  1916 
  1917 *** HOL-Algebra ***
  1918 
  1919 * New locales for orders and lattices where the equivalence relation
  1920 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  1921 locales use a record structure with field eq for the equivalence.
  1922 
  1923 * New theory of factorial domains.
  1924 
  1925 * Units_l_inv and Units_r_inv are now simp rules by default.
  1926 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  1927 and/or r_inv will now also require deletion of these lemmas.
  1928 
  1929 * Renamed the following theorems, INCOMPATIBILITY:
  1930 
  1931 UpperD ~> Upper_memD
  1932 LowerD ~> Lower_memD
  1933 least_carrier ~> least_closed
  1934 greatest_carrier ~> greatest_closed
  1935 greatest_Lower_above ~> greatest_Lower_below
  1936 one_zero ~> carrier_one_zero
  1937 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  1938 
  1939 
  1940 *** HOL-Nominal ***
  1941 
  1942 * Nominal datatypes can now contain type-variables.
  1943 
  1944 * Commands 'nominal_inductive' and 'equivariance' work with local
  1945 theory targets.
  1946 
  1947 * Nominal primrec can now works with local theory targets and its
  1948 specification syntax now conforms to the general format as seen in
  1949 'inductive' etc.
  1950 
  1951 * Method "perm_simp" honours the standard simplifier attributes
  1952 (no_asm), (no_asm_use) etc.
  1953 
  1954 * The new predicate #* is defined like freshness, except that on the
  1955 left hand side can be a set or list of atoms.
  1956 
  1957 * Experimental command 'nominal_inductive2' derives strong induction
  1958 principles for inductive definitions.  In contrast to
  1959 'nominal_inductive', which can only deal with a fixed number of
  1960 binders, it can deal with arbitrary expressions standing for sets of
  1961 atoms to be avoided.  The only inductive definition we have at the
  1962 moment that needs this generalisation is the typing rule for Lets in
  1963 the algorithm W:
  1964 
  1965  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  1966  -----------------------------------------------------------------
  1967          Gamma |- Let x be t1 in t2 : T2
  1968 
  1969 In this rule one wants to avoid all the binders that are introduced by
  1970 "close Gamma T1".  We are looking for other examples where this
  1971 feature might be useful.  Please let us know.
  1972 
  1973 
  1974 *** HOLCF ***
  1975 
  1976 * Reimplemented the simplification procedure for proving continuity
  1977 subgoals.  The new simproc is extensible; users can declare additional
  1978 continuity introduction rules with the attribute [cont2cont].
  1979 
  1980 * The continuity simproc now uses a different introduction rule for
  1981 solving continuity subgoals on terms with lambda abstractions.  In
  1982 some rare cases the new simproc may fail to solve subgoals that the
  1983 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  1984 Potential INCOMPATIBILITY.
  1985 
  1986 * Command 'fixrec': specification syntax now conforms to the general
  1987 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  1988 examples.  INCOMPATIBILITY.
  1989 
  1990 
  1991 *** ZF ***
  1992 
  1993 * Proof of Zorn's Lemma for partial orders.
  1994 
  1995 
  1996 *** ML ***
  1997 
  1998 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  1999 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2000 depends on multithreading, so timouts will not work before Poly/ML
  2001 5.2.1!
  2002 
  2003 * High-level support for concurrent ML programming, see
  2004 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2005 particularly convenient to organize independent functional
  2006 computations.  The concept of "synchronized variables" provides a
  2007 higher-order interface for components with shared state, avoiding the
  2008 delicate details of mutexes and condition variables.  (Requires
  2009 Poly/ML 5.2.1 or later.)
  2010 
  2011 * ML bindings produced via Isar commands are stored within the Isar
  2012 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2013 become thread-safe and work with undo as expected (concerning
  2014 top-level bindings, not side-effects on global references).
  2015 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2016 compiler at runtime; really global bindings need to be given outside a
  2017 theory.  (Requires Poly/ML 5.2 or later.)
  2018 
  2019 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2020 context.  Top-level ML bindings are stored within the proof context in
  2021 a purely sequential fashion, disregarding the nested proof structure.
  2022 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2023 proof.  (Requires Poly/ML 5.2 or later.)
  2024 
  2025 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2026 and Method.setup, as well as Isar commands 'attribute_setup' and
  2027 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2028 existing code accordingly, or use plain 'setup' together with old
  2029 Method.add_method.
  2030 
  2031 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2032 to 'a -> thm, while results are always tagged with an authentic oracle
  2033 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2034 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2035 accordingly.  Note that extra performance may be gained by producing
  2036 the cterm carefully, avoiding slow Thm.cterm_of.
  2037 
  2038 * Simplified interface for defining document antiquotations via
  2039 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2040 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2041 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2042 examples.
  2043 
  2044 * More systematic treatment of long names, abstract name bindings, and
  2045 name space operations.  Basic operations on qualified names have been
  2046 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2047 Long_Name.append.  Old type bstring has been mostly replaced by
  2048 abstract type binding (see structure Binding), which supports precise
  2049 qualification by packages and local theory targets, as well as proper
  2050 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2051 bstring values into Binding.name, or better pass through abstract
  2052 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2053 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2054 
  2055 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2056 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2057 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2058 
  2059 * Disposed old type and term read functions (Sign.read_def_typ,
  2060 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2061 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2062 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2063 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2064 resort for legacy applications.
  2065 
  2066 * Disposed old declarations, tactics, tactic combinators that refer to
  2067 the simpset or claset of an implicit theory (such as Addsimps,
  2068 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2069 embedded ML text, or local_simpset_of with a proper context passed as
  2070 explicit runtime argument.
  2071 
  2072 * Rules and tactics that read instantiations (read_instantiate,
  2073 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2074 context, which is required for parsing and type-checking.  Moreover,
  2075 the variables are specified as plain indexnames, not string encodings
  2076 thereof.  INCOMPATIBILITY.
  2077 
  2078 * Generic Toplevel.add_hook interface allows to analyze the result of
  2079 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2080 for theorem dependency output of transactions resulting in a new
  2081 theory state.
  2082 
  2083 * ML antiquotations: block-structured compilation context indicated by
  2084 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2085 
  2086   @{binding name}                         - basic name binding
  2087   @{let ?pat = term}                      - term abbreviation (HO matching)
  2088   @{note name = fact}                     - fact abbreviation
  2089   @{thm fact}                             - singleton fact (with attributes)
  2090   @{thms fact}                            - general fact (with attributes)
  2091   @{lemma prop by method}                 - singleton goal
  2092   @{lemma prop by meth1 meth2}            - singleton goal
  2093   @{lemma prop1 ... propN by method}      - general goal
  2094   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2095   @{lemma (open) ...}                     - open derivation
  2096 
  2097 
  2098 *** System ***
  2099 
  2100 * The Isabelle "emacs" tool provides a specific interface to invoke
  2101 Proof General / Emacs, with more explicit failure if that is not
  2102 installed (the old isabelle-interface script silently falls back on
  2103 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2104 installation location of the Proof General distribution.
  2105 
  2106 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2107 the Isabelle process into a JVM/Scala application.  See
  2108 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2109 process wrapper has been discontinued.)
  2110 
  2111 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2112 
  2113 * Various status messages (with exact source position information) are
  2114 emitted, if proper markup print mode is enabled.  This allows
  2115 user-interface components to provide detailed feedback on internal
  2116 prover operations.
  2117 
  2118 
  2119 
  2120 New in Isabelle2008 (June 2008)
  2121 -------------------------------
  2122 
  2123 *** General ***
  2124 
  2125 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2126 and updated, with formally checked references as hyperlinks.
  2127 
  2128 * Theory loader: use_thy (and similar operations) no longer set the
  2129 implicit ML context, which was occasionally hard to predict and in
  2130 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2131 provides a proper context already.
  2132 
  2133 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2134 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2135 'use' within a theory file will do the job.
  2136 
  2137 * Name space merge now observes canonical order, i.e. the second space
  2138 is inserted into the first one, while existing entries in the first
  2139 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2140 swap theory imports.
  2141 
  2142 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2143 INCOMPATIBILITY in identifier syntax etc.
  2144 
  2145 * Outer syntax: string tokens no longer admit escaped white space,
  2146 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2147 white space without escapes.
  2148 
  2149 * Outer syntax: string tokens may contain arbitrary character codes
  2150 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2151 "foo_bar".
  2152 
  2153 
  2154 *** Pure ***
  2155 
  2156 * Context-dependent token translations.  Default setup reverts locally
  2157 fixed variables, and adds hilite markup for undeclared frees.
  2158 
  2159 * Unused theorems can be found using the new command 'unused_thms'.
  2160 There are three ways of invoking it:
  2161 
  2162 (1) unused_thms
  2163      Only finds unused theorems in the current theory.
  2164 
  2165 (2) unused_thms thy_1 ... thy_n -
  2166      Finds unused theorems in the current theory and all of its ancestors,
  2167      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2168 
  2169 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2170      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2171      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2172      their ancestors.
  2173 
  2174 In order to increase the readability of the list produced by
  2175 unused_thms, theorems that have been created by a particular instance
  2176 of a theory command such as 'inductive' or 'function' are considered
  2177 to belong to the same "group", meaning that if at least one theorem in
  2178 this group is used, the other theorems in the same group are no longer
  2179 reported as unused.  Moreover, if all theorems in the group are
  2180 unused, only one theorem in the group is displayed.
  2181 
  2182 Note that proof objects have to be switched on in order for
  2183 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2184 usually the case when using Proof General with the default settings).
  2185 
  2186 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2187 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2188 duplicate fact bindings, or even accidental fact duplications.  Note
  2189 that tools may maintain dynamically scoped facts systematically, using
  2190 PureThy.add_thms_dynamic.
  2191 
  2192 * Command 'hide' now allows to hide from "fact" name space as well.
  2193 
  2194 * Eliminated destructive theorem database, simpset, claset, and
  2195 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2196 update of theories within ML code.
  2197 
  2198 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2199 INCOMPATIBILITY, object-logics depending on former Pure require
  2200 additional setup PureThy.old_appl_syntax_setup; object-logics
  2201 depending on former CPure need to refer to Pure.
  2202 
  2203 * Commands 'use' and 'ML' are now purely functional, operating on
  2204 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2205 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2206 INCOMPATIBILITY.
  2207 
  2208 * Command 'setup': discontinued implicit version with ML reference.
  2209 
  2210 * Instantiation target allows for simultaneous specification of class
  2211 instance operations together with an instantiation proof.
  2212 Type-checking phase allows to refer to class operations uniformly.
  2213 See src/HOL/Complex/Complex.thy for an Isar example and
  2214 src/HOL/Library/Eval.thy for an ML example.
  2215 
  2216 * Indexing of literal facts: be more serious about including only
  2217 facts from the visible specification/proof context, but not the
  2218 background context (locale etc.).  Affects `prop` notation and method
  2219 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2220 situations.
  2221 
  2222 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2223 "(open)" option, which used to expose internal bound variables to the
  2224 proof text.
  2225 
  2226 * Isar statements: removed obsolete case "rule_context".
  2227 INCOMPATIBILITY, better use explicit fixes/assumes.
  2228 
  2229 * Locale proofs: default proof step now includes 'unfold_locales';
  2230 hence 'proof' without argument may be used to unfold locale
  2231 predicates.
  2232 
  2233 
  2234 *** Document preparation ***
  2235 
  2236 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2237 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2238 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2239 spot); renamed link color from "darkblue" to "linkcolor" (default
  2240 value unchanged, can be redefined via \definecolor); no longer sets
  2241 "a4paper" option (unnecessary or even intrusive).
  2242 
  2243 * Antiquotation @{lemma A method} proves proposition A by the given
  2244 method (either a method name or a method name plus (optional) method
  2245 arguments in parentheses) and prints A just like @{prop A}.
  2246 
  2247 
  2248 *** HOL ***
  2249 
  2250 * New primrec package.  Specification syntax conforms in style to
  2251 definition/function/....  No separate induction rule is provided.  The
  2252 "primrec" command distinguishes old-style and new-style specifications
  2253 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2254 When adjusting theories, beware: constants stemming from new-style
  2255 primrec specifications have authentic syntax.
  2256 
  2257 * Metis prover is now an order of magnitude faster, and also works
  2258 with multithreading.
  2259 
  2260 * Metis: the maximum number of clauses that can be produced from a
  2261 theorem is now given by the attribute max_clauses.  Theorems that
  2262 exceed this number are ignored, with a warning printed.
  2263 
  2264 * Sledgehammer no longer produces structured proofs by default. To
  2265 enable, declare [[sledgehammer_full = true]].  Attributes
  2266 reconstruction_modulus, reconstruction_sorts renamed
  2267 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2268 
  2269 * Method "induct_scheme" derives user-specified induction rules
  2270 from well-founded induction and completeness of patterns. This factors
  2271 out some operations that are done internally by the function package
  2272 and makes them available separately.  See
  2273 src/HOL/ex/Induction_Scheme.thy for examples.
  2274 
  2275 * More flexible generation of measure functions for termination
  2276 proofs: Measure functions can be declared by proving a rule of the
  2277 form "is_measure f" and giving it the [measure_function] attribute.
  2278 The "is_measure" predicate is logically meaningless (always true), and
  2279 just guides the heuristic.  To find suitable measure functions, the
  2280 termination prover sets up the goal "is_measure ?f" of the appropriate
  2281 type and generates all solutions by prolog-style backwards proof using
  2282 the declared rules.
  2283 
  2284 This setup also deals with rules like 
  2285 
  2286   "is_measure f ==> is_measure (list_size f)"
  2287 
  2288 which accommodates nested datatypes that recurse through lists.
  2289 Similar rules are predeclared for products and option types.
  2290 
  2291 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2292 
  2293   INCOMPATIBILITIES:
  2294 
  2295   - Definitions of overloaded constants on sets have to be replaced by
  2296     definitions on => and bool.
  2297 
  2298   - Some definitions of overloaded operators on sets can now be proved
  2299     using the definitions of the operators on => and bool.  Therefore,
  2300     the following theorems have been renamed:
  2301 
  2302       subset_def   -> subset_eq
  2303       psubset_def  -> psubset_eq
  2304       set_diff_def -> set_diff_eq
  2305       Compl_def    -> Compl_eq
  2306       Sup_set_def  -> Sup_set_eq
  2307       Inf_set_def  -> Inf_set_eq
  2308       sup_set_def  -> sup_set_eq
  2309       inf_set_def  -> inf_set_eq
  2310 
  2311   - Due to the incompleteness of the HO unification algorithm, some
  2312     rules such as subst may require manual instantiation, if some of
  2313     the unknowns in the rule is a set.
  2314 
  2315   - Higher order unification and forward proofs:
  2316     The proof pattern
  2317 
  2318       have "P (S::'a set)" <...>
  2319       then have "EX S. P S" ..
  2320 
  2321     no longer works (due to the incompleteness of the HO unification
  2322     algorithm) and must be replaced by the pattern
  2323 
  2324       have "EX S. P S"
  2325       proof
  2326         show "P S" <...>
  2327       qed
  2328 
  2329   - Calculational reasoning with subst (or similar rules):
  2330     The proof pattern
  2331 
  2332       have "P (S::'a set)" <...>
  2333       also have "S = T" <...>
  2334       finally have "P T" .
  2335 
  2336     no longer works (for similar reasons as the previous example) and
  2337     must be replaced by something like
  2338 
  2339       have "P (S::'a set)" <...>
  2340       moreover have "S = T" <...>
  2341       ultimately have "P T" by simp
  2342 
  2343   - Tactics or packages written in ML code:
  2344     Code performing pattern matching on types via
  2345 
  2346       Type ("set", [T]) => ...
  2347 
  2348     must be rewritten. Moreover, functions like strip_type or
  2349     binder_types no longer return the right value when applied to a
  2350     type of the form
  2351 
  2352       T1 => ... => Tn => U => bool
  2353 
  2354     rather than
  2355 
  2356       T1 => ... => Tn => U set
  2357 
  2358 * Merged theories Wellfounded_Recursion, Accessible_Part and
  2359 Wellfounded_Relations to theory Wellfounded.
  2360 
  2361 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  2362 
  2363 * Class finite no longer treats UNIV as class parameter.  Use class
  2364 enum from theory Library/Enum instead to achieve a similar effect.
  2365 INCOMPATIBILITY.
  2366 
  2367 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  2368 and "Cons".  INCOMPATIBILITY.
  2369 
  2370 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  2371 Potential INCOMPATIBILITY.
  2372 
  2373 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  2374 injective_fst_snd removed, use split_eta and prod_eqI instead.
  2375 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  2376 
  2377 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  2378 the same name in theory Orderings:
  2379 
  2380   less_trans
  2381   less_linear
  2382   le_imp_less_or_eq
  2383   le_less_trans
  2384   less_le_trans
  2385   less_not_sym
  2386   less_asym
  2387 
  2388 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  2389 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  2390 and different variable names.
  2391 
  2392 * Library/Option_ord.thy: Canonical order on option type.
  2393 
  2394 * Library/RBT.thy: Red-black trees, an efficient implementation of
  2395 finite maps.
  2396 
  2397 * Library/Countable.thy: Type class for countable types.
  2398 
  2399 * Theory Int: The representation of numerals has changed.  The infix
  2400 operator BIT and the bit datatype with constructors B0 and B1 have
  2401 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  2402 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  2403 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  2404 accordingly.
  2405 
  2406 * Theory Nat: definition of <= and < on natural numbers no longer
  2407 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  2408 le_def and less_def have disappeared.  Consider lemmas not_less
  2409 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  2410 
  2411 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  2412 (whose purpose mainly is for various fold_set functionals) have been
  2413 abandoned in favor of the existing algebraic classes
  2414 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  2415 lower_semilattice (resp. upper_semilattice) and linorder.
  2416 INCOMPATIBILITY.
  2417 
  2418 * Theory Transitive_Closure: induct and cases rules now declare proper
  2419 case_names ("base" and "step").  INCOMPATIBILITY.
  2420 
  2421 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  2422 lattices.  The form set-specific version is available as
  2423 Inductive.lfp_ordinal_induct_set.
  2424 
  2425 * Renamed theorems "power.simps" to "power_int.simps".
  2426 INCOMPATIBILITY.
  2427 
  2428 * Class semiring_div provides basic abstract properties of semirings
  2429 with division and modulo operations.  Subsumes former class dvd_mod.
  2430 
  2431 * Merged theories IntDef, Numeral and IntArith into unified theory
  2432 Int.  INCOMPATIBILITY.
  2433 
  2434 * Theory Library/Code_Index: type "index" now represents natural
  2435 numbers rather than integers.  INCOMPATIBILITY.
  2436 
  2437 * New class "uminus" with operation "uminus" (split of from class
  2438 "minus" which now only has operation "minus", binary).
  2439 INCOMPATIBILITY.
  2440 
  2441 * Constants "card", "internal_split", "option_map" now with authentic
  2442 syntax.  INCOMPATIBILITY.
  2443 
  2444 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  2445 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  2446 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  2447 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  2448 Sup_set_def, le_def, less_def, option_map_def now with object
  2449 equality.  INCOMPATIBILITY.
  2450 
  2451 * Records. Removed K_record, and replaced it by pure lambda term
  2452 %x. c. The simplifier setup is now more robust against eta expansion.
  2453 INCOMPATIBILITY: in cases explicitly referring to K_record.
  2454 
  2455 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  2456 
  2457 * Library/ListVector: new theory of arithmetic vector operations.
  2458 
  2459 * Library/Order_Relation: new theory of various orderings as sets of
  2460 pairs.  Defines preorders, partial orders, linear orders and
  2461 well-orders on sets and on types.
  2462 
  2463 
  2464 *** ZF ***
  2465 
  2466 * Renamed some theories to allow to loading both ZF and HOL in the
  2467 same session:
  2468 
  2469   Datatype  -> Datatype_ZF
  2470   Inductive -> Inductive_ZF
  2471   Int       -> Int_ZF
  2472   IntDiv    -> IntDiv_ZF
  2473   Nat       -> Nat_ZF
  2474   List      -> List_ZF
  2475   Main      -> Main_ZF
  2476 
  2477 INCOMPATIBILITY: ZF theories that import individual theories below
  2478 Main might need to be adapted.  Regular theory Main is still
  2479 available, as trivial extension of Main_ZF.
  2480 
  2481 
  2482 *** ML ***
  2483 
  2484 * ML within Isar: antiquotation @{const name} or @{const
  2485 name(typargs)} produces statically-checked Const term.
  2486 
  2487 * Functor NamedThmsFun: data is available to the user as dynamic fact
  2488 (of the same name).  Removed obsolete print command.
  2489 
  2490 * Removed obsolete "use_legacy_bindings" function.
  2491 
  2492 * The ``print mode'' is now a thread-local value derived from a global
  2493 template (the former print_mode reference), thus access becomes
  2494 non-critical.  The global print_mode reference is for session
  2495 management only; user-code should use print_mode_value,
  2496 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  2497 
  2498 * Functions system/system_out provide a robust way to invoke external
  2499 shell commands, with propagation of interrupts (requires Poly/ML
  2500 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  2501 
  2502 
  2503 *** System ***
  2504 
  2505 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  2506 in accordance with Proof General 3.7, which prefers GNU emacs.
  2507 
  2508 * isatool tty runs Isabelle process with plain tty interaction;
  2509 optional line editor may be specified via ISABELLE_LINE_EDITOR
  2510 setting, the default settings attempt to locate "ledit" and "rlwrap".
  2511 
  2512 * isatool browser now works with Cygwin as well, using general
  2513 "javapath" function defined in Isabelle process environment.
  2514 
  2515 * YXML notation provides a simple and efficient alternative to
  2516 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  2517 isatool yxml as described in the Isabelle system manual.
  2518 
  2519 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  2520 provides general wrapper for managing an Isabelle process in a robust
  2521 fashion, with ``cooked'' output from stdin/stderr.
  2522 
  2523 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  2524 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  2525 
  2526 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  2527 way of changing the user's settings is via
  2528 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  2529 script.
  2530 
  2531 * Multithreading.max_threads := 0 refers to the number of actual CPU
  2532 cores of the underlying machine, which is a good starting point for
  2533 optimal performance tuning.  The corresponding usedir option -M allows
  2534 "max" as an alias for "0".  WARNING: does not work on certain versions
  2535 of Mac OS (with Poly/ML 5.1).
  2536 
  2537 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  2538 adverse effect of Isabelle flooding interactive front-ends (notably
  2539 ProofGeneral / XEmacs).
  2540 
  2541 
  2542 
  2543 New in Isabelle2007 (November 2007)
  2544 -----------------------------------
  2545 
  2546 *** General ***
  2547 
  2548 * More uniform information about legacy features, notably a
  2549 warning/error of "Legacy feature: ...", depending on the state of the
  2550 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  2551 legacy features will disappear eventually.
  2552 
  2553 * Theory syntax: the header format ``theory A = B + C:'' has been
  2554 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  2555 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  2556 
  2557 * Theory syntax: the old non-Isar theory file format has been
  2558 discontinued altogether.  Note that ML proof scripts may still be used
  2559 with Isar theories; migration is usually quite simple with the ML
  2560 function use_legacy_bindings.  INCOMPATIBILITY.
  2561 
  2562 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  2563 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  2564 quotes.
  2565 
  2566 * Theory loader: be more serious about observing the static theory
  2567 header specifications (including optional directories), but not the
  2568 accidental file locations of previously successful loads.  The strict
  2569 update policy of former update_thy is now already performed by
  2570 use_thy, so the former has been removed; use_thys updates several
  2571 theories simultaneously, just as 'imports' within a theory header
  2572 specification, but without merging the results.  Potential
  2573 INCOMPATIBILITY: may need to refine theory headers and commands
  2574 ROOT.ML which depend on load order.
  2575 
  2576 * Theory loader: optional support for content-based file
  2577 identification, instead of the traditional scheme of full physical
  2578 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  2579 (cf. the system manual).  The new scheme allows to work with
  2580 non-finished theories in persistent session images, such that source
  2581 files may be moved later on without requiring reloads.
  2582 
  2583 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2584 file (with the same base name as the theory) are considered a legacy
  2585 feature, which will disappear eventually. Even now, the theory loader
  2586 no longer maintains dependencies on such files.
  2587 
  2588 * Syntax: the scope for resolving ambiguities via type-inference is
  2589 now limited to individual terms, instead of whole simultaneous
  2590 specifications as before. This greatly reduces the complexity of the
  2591 syntax module and improves flexibility by separating parsing and
  2592 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  2593 'fixes' etc.) are required in rare situations.
  2594 
  2595 * Syntax: constants introduced by new-style packages ('definition',
  2596 'abbreviation' etc.) are passed through the syntax module in
  2597 ``authentic mode''. This means that associated mixfix annotations
  2598 really stick to such constants, independently of potential name space
  2599 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  2600 trees are represented slightly differently, may need to adapt syntax
  2601 translations accordingly. Use CONST marker in 'translations' and
  2602 @{const_syntax} antiquotation in 'parse_translation' etc.
  2603 
  2604 * Legacy goal package: reduced interface to the bare minimum required
  2605 to keep existing proof scripts running.  Most other user-level
  2606 functions are now part of the OldGoals structure, which is *not* open
  2607 by default (consider isatool expandshort before open OldGoals).
  2608 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  2609 these tend to cause confusion about the actual goal (!) context being
  2610 used here, which is not necessarily the same as the_context().
  2611 
  2612 * Command 'find_theorems': supports "*" wild-card in "name:"
  2613 criterion; "with_dups" option.  Certain ProofGeneral versions might
  2614 support a specific search form (see ProofGeneral/CHANGES).
  2615 
  2616 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  2617 by default, which means that "prems" (and also "fixed variables") are
  2618 suppressed from proof state output.  Note that the ProofGeneral
  2619 settings mechanism allows to change and save options persistently, but
  2620 older versions of Isabelle will fail to start up if a negative prems
  2621 limit is imposed.
  2622 
  2623 * Local theory targets may be specified by non-nested blocks of
  2624 ``context/locale/class ... begin'' followed by ``end''.  The body may
  2625 contain definitions, theorems etc., including any derived mechanism
  2626 that has been implemented on top of these primitives.  This concept
  2627 generalizes the existing ``theorem (in ...)'' towards more versatility
  2628 and scalability.
  2629 
  2630 * Proof General interface: proper undo of final 'end' command;
  2631 discontinued Isabelle/classic mode (ML proof scripts).
  2632 
  2633 
  2634 *** Document preparation ***
  2635 
  2636 * Added antiquotation @{theory name} which prints the given name,
  2637 after checking that it refers to a valid ancestor theory in the
  2638 current context.
  2639 
  2640 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  2641 check the given source text as ML type/structure, printing verbatim.
  2642 
  2643 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  2644 "c args == rhs" given in the current context.  (Any number of
  2645 arguments may be given on the LHS.)
  2646 
  2647 
  2648 *** Pure ***
  2649 
  2650 * The 'class' package offers a combination of axclass and locale to
  2651 achieve Haskell-like type classes in Isabelle.  Definitions and
  2652 theorems within a class context produce both relative results (with
  2653 implicit parameters according to the locale context), and polymorphic
  2654 constants with qualified polymorphism (according to the class
  2655 context).  Within the body context of a 'class' target, a separate
  2656 syntax layer ("user space type system") takes care of converting
  2657 between global polymorphic consts and internal locale representation.
  2658 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  2659 "isatool doc classes" provides a tutorial.
  2660 
  2661 * Generic code generator framework allows to generate executable
  2662 code for ML and Haskell (including Isabelle classes).  A short usage
  2663 sketch:
  2664 
  2665     internal compilation:
  2666         export_code <list of constants (term syntax)> in SML
  2667     writing SML code to a file:
  2668         export_code <list of constants (term syntax)> in SML <filename>
  2669     writing OCaml code to a file:
  2670         export_code <list of constants (term syntax)> in OCaml <filename>
  2671     writing Haskell code to a bunch of files:
  2672         export_code <list of constants (term syntax)> in Haskell <filename>
  2673 
  2674     evaluating closed propositions to True/False using code generation:
  2675         method ``eval''
  2676 
  2677 Reasonable default setup of framework in HOL.
  2678 
  2679 Theorem attributs for selecting and transforming function equations theorems:
  2680 
  2681     [code fun]:        select a theorem as function equation for a specific constant
  2682     [code fun del]:    deselect a theorem as function equation for a specific constant
  2683     [code inline]:     select an equation theorem for unfolding (inlining) in place
  2684     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  2685 
  2686 User-defined serializations (target in {SML, OCaml, Haskell}):
  2687 
  2688     code_const <and-list of constants (term syntax)>
  2689       {(target) <and-list of const target syntax>}+
  2690 
  2691     code_type <and-list of type constructors>
  2692       {(target) <and-list of type target syntax>}+
  2693 
  2694     code_instance <and-list of instances>
  2695       {(target)}+
  2696         where instance ::= <type constructor> :: <class>
  2697 
  2698     code_class <and_list of classes>
  2699       {(target) <and-list of class target syntax>}+
  2700         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  2701 
  2702 code_instance and code_class only are effective to target Haskell.
  2703 
  2704 For example usage see src/HOL/ex/Codegenerator.thy and
  2705 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  2706 generation from Isabelle/HOL theories is available via "isatool doc
  2707 codegen".
  2708 
  2709 * Code generator: consts in 'consts_code' Isar commands are now
  2710 referred to by usual term syntax (including optional type
  2711 annotations).
  2712 
  2713 * Command 'no_translations' removes translation rules from theory
  2714 syntax.
  2715 
  2716 * Overloaded definitions are now actually checked for acyclic
  2717 dependencies.  The overloading scheme is slightly more general than
  2718 that of Haskell98, although Isabelle does not demand an exact
  2719 correspondence to type class and instance declarations.
  2720 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  2721 exotic versions of overloading -- at the discretion of the user!
  2722 
  2723 Polymorphic constants are represented via type arguments, i.e. the
  2724 instantiation that matches an instance against the most general
  2725 declaration given in the signature.  For example, with the declaration
  2726 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  2727 as c(nat).  Overloading is essentially simultaneous structural
  2728 recursion over such type arguments.  Incomplete specification patterns
  2729 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  2730 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  2731 Command 'print_theory' outputs the normalized system of recursive
  2732 equations, see section "definitions".
  2733 
  2734 * Configuration options are maintained within the theory or proof
  2735 context (with name and type bool/int/string), providing a very simple
  2736 interface to a poor-man's version of general context data.  Tools may
  2737 declare options in ML (e.g. using Attrib.config_int) and then refer to
  2738 these values using Config.get etc.  Users may change options via an
  2739 associated attribute of the same name.  This form of context
  2740 declaration works particularly well with commands 'declare' or
  2741 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  2742 very easy to avoid global references, which would not observe Isar
  2743 toplevel undo/redo and fail to work with multithreading.
  2744 
  2745 Various global ML references of Pure and HOL have been turned into
  2746 configuration options:
  2747 
  2748   Unify.search_bound		unify_search_bound
  2749   Unify.trace_bound		unify_trace_bound
  2750   Unify.trace_simp		unify_trace_simp
  2751   Unify.trace_types		unify_trace_types
  2752   Simplifier.simp_depth_limit	simp_depth_limit
  2753   Blast.depth_limit		blast_depth_limit
  2754   DatatypeProp.dtK		datatype_distinctness_limit
  2755   fast_arith_neq_limit  	fast_arith_neq_limit
  2756   fast_arith_split_limit	fast_arith_split_limit
  2757 
  2758 * Named collections of theorems may be easily installed as context
  2759 data using the functor NamedThmsFun (see also
  2760 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  2761 attributes; there is also a toplevel print command.  This facility is
  2762 just a common case of general context data, which is the preferred way
  2763 for anything more complex than just a list of facts in canonical
  2764 order.
  2765 
  2766 * Isar: command 'declaration' augments a local theory by generic
  2767 declaration functions written in ML.  This enables arbitrary content
  2768 being added to the context, depending on a morphism that tells the
  2769 difference of the original declaration context wrt. the application
  2770 context encountered later on.
  2771 
  2772 * Isar: proper interfaces for simplification procedures.  Command
  2773 'simproc_setup' declares named simprocs (with match patterns, and body
  2774 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  2775 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  2776 
  2777 * Isar: an extra pair of brackets around attribute declarations
  2778 abbreviates a theorem reference involving an internal dummy fact,
  2779 which will be ignored later --- only the effect of the attribute on
  2780 the background context will persist.  This form of in-place
  2781 declarations is particularly useful with commands like 'declare' and
  2782 'using', for example ``have A using [[simproc a]] by simp''.
  2783 
  2784 * Isar: method "assumption" (and implicit closing of subproofs) now
  2785 takes simple non-atomic goal assumptions into account: after applying
  2786 an assumption as a rule the resulting subgoals are solved by atomic
  2787 assumption steps.  This is particularly useful to finish 'obtain'
  2788 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  2789 without referring to the original premise "!!x. P x ==> thesis" in the
  2790 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  2791 more permissive.
  2792 
  2793 * Isar: implicit use of prems from the Isar proof context is
  2794 considered a legacy feature.  Common applications like ``have A .''
  2795 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  2796 referencing facts explicitly here improves readability and
  2797 maintainability of proof texts.
  2798 
  2799 * Isar: improper proof element 'guess' is like 'obtain', but derives
  2800 the obtained context from the course of reasoning!  For example:
  2801 
  2802   assume "EX x y. A x & B y"   -- "any previous fact"
  2803   then guess x and y by clarify
  2804 
  2805 This technique is potentially adventurous, depending on the facts and
  2806 proof tools being involved here.
  2807 
  2808 * Isar: known facts from the proof context may be specified as literal
  2809 propositions, using ASCII back-quote syntax.  This works wherever
  2810 named facts used to be allowed so far, in proof commands, proof
  2811 methods, attributes etc.  Literal facts are retrieved from the context
  2812 according to unification of type and term parameters.  For example,
  2813 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  2814 theorems in the current context, then these are valid literal facts:
  2815 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  2816 
  2817 There is also a proof method "fact" which does the same composition
  2818 for explicit goal states, e.g. the following proof texts coincide with
  2819 certain special cases of literal facts:
  2820 
  2821   have "A" by fact                 ==  note `A`
  2822   have "A ==> B" by fact           ==  note `A ==> B`
  2823   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  2824   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  2825 
  2826 * Isar: ":" (colon) is no longer a symbolic identifier character in
  2827 outer syntax.  Thus symbolic identifiers may be used without
  2828 additional white space in declarations like this: ``assume *: A''.
  2829 
  2830 * Isar: 'print_facts' prints all local facts of the current context,
  2831 both named and unnamed ones.
  2832 
  2833 * Isar: 'def' now admits simultaneous definitions, e.g.:
  2834 
  2835   def x == "t" and y == "u"
  2836 
  2837 * Isar: added command 'unfolding', which is structurally similar to
  2838 'using', but affects both the goal state and facts by unfolding given
  2839 rewrite rules.  Thus many occurrences of the 'unfold' method or
  2840 'unfolded' attribute may be replaced by first-class proof text.
  2841 
  2842 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  2843 and command 'unfolding' now all support object-level equalities
  2844 (potentially conditional).  The underlying notion of rewrite rule is
  2845 analogous to the 'rule_format' attribute, but *not* that of the
  2846 Simplifier (which is usually more generous).
  2847 
  2848 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  2849 premises of a theorem by n. Useful in conjunction with drule.
  2850 
  2851 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  2852 method expression within a sandbox consisting of the first N
  2853 sub-goals, which need to exist.  For example, ``simp_all [3]''
  2854 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  2855 simplifies all new goals that emerge from applying rule foo to the
  2856 originally first one.
  2857 
  2858 * Isar: schematic goals are no longer restricted to higher-order
  2859 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  2860 expected.
  2861 
  2862 * Isar: the conclusion of a long theorem statement is now either
  2863 'shows' (a simultaneous conjunction, as before), or 'obtains'
  2864 (essentially a disjunction of cases with local parameters and
  2865 assumptions).  The latter allows to express general elimination rules
  2866 adequately; in this notation common elimination rules look like this:
  2867 
  2868   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  2869     assumes "EX x. P x"
  2870     obtains x where "P x"
  2871 
  2872   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  2873     assumes "A & B"
  2874     obtains A and B
  2875 
  2876   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  2877     assumes "A | B"
  2878     obtains
  2879       A
  2880     | B
  2881 
  2882 The subsequent classical rules even refer to the formal "thesis"
  2883 explicitly:
  2884 
  2885   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  2886     obtains "~ thesis"
  2887 
  2888   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  2889     obtains "thesis ==> something"
  2890 
  2891 The actual proof of an 'obtains' statement is analogous to that of the
  2892 Isar proof element 'obtain', only that there may be several cases.
  2893 Optional case names may be specified in parentheses; these will be
  2894 available both in the present proof and as annotations in the
  2895 resulting rule, for later use with the 'cases' method (cf. attribute
  2896 case_names).
  2897 
  2898 * Isar: the assumptions of a long theorem statement are available as
  2899 "assms" fact in the proof context.  This is more appropriate than the
  2900 (historical) "prems", which refers to all assumptions of the current
  2901 context, including those from the target locale, proof body etc.
  2902 
  2903 * Isar: 'print_statement' prints theorems from the current theory or
  2904 proof context in long statement form, according to the syntax of a
  2905 top-level lemma.
  2906 
  2907 * Isar: 'obtain' takes an optional case name for the local context
  2908 introduction rule (default "that").
  2909 
  2910 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  2911 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  2912 to occur.
  2913 
  2914 * Pure: syntax "CONST name" produces a fully internalized constant
  2915 according to the current context.  This is particularly useful for
  2916 syntax translations that should refer to internal constant
  2917 representations independently of name spaces.
  2918 
  2919 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  2920 instead of "FOO ". This allows multiple binder declarations to coexist
  2921 in the same context.  INCOMPATIBILITY.
  2922 
  2923 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  2924 primitive that also works in a locale context (both for constants and
  2925 fixed variables). Type declaration and internal syntactic representation
  2926 of given constants retrieved from the context. Likewise, the
  2927 'no_notation' command allows to remove given syntax annotations from the
  2928 current context.
  2929 
  2930 * Isar/locales: new derived specification elements 'axiomatization',
  2931 'definition', 'abbreviation', which support type-inference, admit
  2932 object-level specifications (equality, equivalence).  See also the
  2933 isar-ref manual.  Examples:
  2934 
  2935   axiomatization
  2936     eq  (infix "===" 50) where
  2937     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  2938 
  2939   definition "f x y = x + y + 1"
  2940   definition g where "g x = f x x"
  2941 
  2942   abbreviation
  2943     neq  (infix "=!=" 50) where
  2944     "x =!= y == ~ (x === y)"
  2945 
  2946 These specifications may be also used in a locale context.  Then the
  2947 constants being introduced depend on certain fixed parameters, and the
  2948 constant name is qualified by the locale base name.  An internal
  2949 abbreviation takes care for convenient input and output, making the
  2950 parameters implicit and using the original short name.  See also
  2951 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  2952 entities from a monomorphic theory.
  2953 
  2954 Presently, abbreviations are only available 'in' a target locale, but
  2955 not inherited by general import expressions.  Also note that
  2956 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  2957 'translations' in common applications.  The "no_abbrevs" print mode
  2958 prevents folding of abbreviations in term output.
  2959 
  2960 Concrete syntax is attached to specified constants in internal form,
  2961 independently of name spaces.  The parse tree representation is
  2962 slightly different -- use 'notation' instead of raw 'syntax', and
  2963 'translations' with explicit "CONST" markup to accommodate this.
  2964 
  2965 * Pure/Isar: unified syntax for new-style specification mechanisms
  2966 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  2967 full type inference and dummy patterns ("_").  For example:
  2968 
  2969   definition "K x _ = x"
  2970 
  2971   inductive conj for A B
  2972   where "A ==> B ==> conj A B"
  2973 
  2974 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  2975 the current context.  Print mode "no_abbrevs" prevents inversion of
  2976 abbreviations on output.
  2977 
  2978 * Isar/locales: improved parameter handling: use of locales "var" and
  2979 "struct" no longer necessary; - parameter renamings are no longer
  2980 required to be injective.  For example, this allows to define
  2981 endomorphisms as locale endom = homom mult mult h.
  2982 
  2983 * Isar/locales: changed the way locales with predicates are defined.
  2984 Instead of accumulating the specification, the imported expression is
  2985 now an interpretation.  INCOMPATIBILITY: different normal form of
  2986 locale expressions.  In particular, in interpretations of locales with
  2987 predicates, goals repesenting already interpreted fragments are not
  2988 removed automatically.  Use methods `intro_locales' and
  2989 `unfold_locales'; see below.
  2990 
  2991 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  2992 provide backward reasoning on locales predicates.  The methods are
  2993 aware of interpretations and discharge corresponding goals.
  2994 `intro_locales' is less aggressive then `unfold_locales' and does not
  2995 unfold predicates to assumptions.
  2996 
  2997 * Isar/locales: the order in which locale fragments are accumulated
  2998 has changed.  This enables to override declarations from fragments due
  2999 to interpretations -- for example, unwanted simp rules.
  3000 
  3001 * Isar/locales: interpretation in theories and proof contexts has been
  3002 extended.  One may now specify (and prove) equations, which are
  3003 unfolded in interpreted theorems.  This is useful for replacing
  3004 defined concepts (constants depending on locale parameters) by
  3005 concepts already existing in the target context.  Example:
  3006 
  3007   interpretation partial_order ["op <= :: [int, int] => bool"]
  3008     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3009 
  3010 Typically, the constant `partial_order.less' is created by a
  3011 definition specification element in the context of locale
  3012 partial_order.
  3013 
  3014 * Method "induct": improved internal context management to support
  3015 local fixes and defines on-the-fly. Thus explicit meta-level
  3016 connectives !!  and ==> are rarely required anymore in inductive goals
  3017 (using object-logic connectives for this purpose has been long
  3018 obsolete anyway). Common proof patterns are explained in
  3019 src/HOL/Induct/Common_Patterns.thy, see also
  3020 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3021 examples.
  3022 
  3023 * Method "induct": improved handling of simultaneous goals. Instead of
  3024 introducing object-level conjunction, the statement is now split into
  3025 several conclusions, while the corresponding symbolic cases are nested
  3026 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3027 see src/HOL/Induct/Common_Patterns.thy, for example.
  3028 
  3029 * Method "induct": mutual induction rules are now specified as a list
  3030 of rule sharing the same induction cases. HOL packages usually provide
  3031 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3032 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3033 mutual induction rules differently, i.e. like this:
  3034 
  3035   (induct rule: foo_bar.inducts)
  3036   (induct set: foo bar)
  3037   (induct pred: foo bar)
  3038   (induct type: foo bar)
  3039 
  3040 The ML function ProjectRule.projections turns old-style rules into the
  3041 new format.
  3042 
  3043 * Method "coinduct": dual of induction, see
  3044 src/HOL/Library/Coinductive_List.thy for various examples.
  3045 
  3046 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3047 considered a legacy feature.
  3048 
  3049 * Attribute "symmetric" produces result with standardized schematic
  3050 variables (index 0).  Potential INCOMPATIBILITY.
  3051 
  3052 * Simplifier: by default the simplifier trace only shows top level
  3053 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3054 default. Thus there is less danger of being flooded by the trace. The
  3055 trace indicates where parts have been suppressed.
  3056   
  3057 * Provers/classical: removed obsolete classical version of elim_format
  3058 attribute; classical elim/dest rules are now treated uniformly when
  3059 manipulating the claset.
  3060 
  3061 * Provers/classical: stricter checks to ensure that supplied intro,
  3062 dest and elim rules are well-formed; dest and elim rules must have at
  3063 least one premise.
  3064 
  3065 * Provers/classical: attributes dest/elim/intro take an optional
  3066 weight argument for the rule (just as the Pure versions).  Weights are
  3067 ignored by automated tools, but determine the search order of single
  3068 rule steps.
  3069 
  3070 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3071 where the body does not mention the bound variable.  Note that dummy
  3072 patterns implicitly depend on their context of bounds, which makes
  3073 "{_. _}" match any set comprehension as expected.  Potential
  3074 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3075 constant "_idtdummy" in the binding position.
  3076 
  3077 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3078 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3079 for example "A -> B" => "Pi A (%_. B)".
  3080 
  3081 * Pure: 'class_deps' command visualizes the subclass relation, using
  3082 the graph browser tool.
  3083 
  3084 * Pure: 'print_theory' now suppresses certain internal declarations by
  3085 default; use '!' option for full details.
  3086 
  3087 
  3088 *** HOL ***
  3089 
  3090 * Method "metis" proves goals by applying the Metis general-purpose
  3091 resolution prover (see also http://gilith.com/software/metis/).
  3092 Examples are in the directory MetisExamples.  WARNING: the
  3093 Isabelle/HOL-Metis integration does not yet work properly with
  3094 multi-threading.
  3095   
  3096 * Command 'sledgehammer' invokes external automatic theorem provers as
  3097 background processes.  It generates calls to the "metis" method if
  3098 successful. These can be pasted into the proof.  Users do not have to
  3099 wait for the automatic provers to return.  WARNING: does not really
  3100 work with multi-threading.
  3101 
  3102 * New "auto_quickcheck" feature tests outermost goal statements for
  3103 potential counter-examples.  Controlled by ML references
  3104 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3105 5000 milliseconds).  Fails silently if statements is outside of
  3106 executable fragment, or any other codgenerator problem occurs.
  3107 
  3108 * New constant "undefined" with axiom "undefined x = undefined".
  3109 
  3110 * Added class "HOL.eq", allowing for code generation with polymorphic
  3111 equality.
  3112 
  3113 * Some renaming of class constants due to canonical name prefixing in
  3114 the new 'class' package:
  3115 
  3116     HOL.abs ~> HOL.abs_class.abs
  3117     HOL.divide ~> HOL.divide_class.divide
  3118     0 ~> HOL.zero_class.zero
  3119     1 ~> HOL.one_class.one
  3120     op + ~> HOL.plus_class.plus
  3121     op - ~> HOL.minus_class.minus
  3122     uminus ~> HOL.minus_class.uminus
  3123     op * ~> HOL.times_class.times
  3124     op < ~> HOL.ord_class.less
  3125     op <= > HOL.ord_class.less_eq
  3126     Nat.power ~> Power.power_class.power
  3127     Nat.size ~> Nat.size_class.size
  3128     Numeral.number_of ~> Numeral.number_class.number_of
  3129     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3130     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3131     Orderings.min ~> Orderings.ord_class.min
  3132     Orderings.max ~> Orderings.ord_class.max
  3133     Divides.op div ~> Divides.div_class.div
  3134     Divides.op mod ~> Divides.div_class.mod
  3135     Divides.op dvd ~> Divides.div_class.dvd
  3136 
  3137 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3138 
  3139 a) User-defined constants using any of the names "plus", "minus",
  3140 "times", "less" or "less_eq". The standard syntax translations for
  3141 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3142 names.
  3143 
  3144 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3145 INCOMPATIBILITY: use more specific names.
  3146 
  3147 c) Permutative equations (e.g. "a + b = b + a")
  3148 Since the change of names also changes the order of terms, permutative
  3149 rewrite rules may get applied in a different order. Experience shows
  3150 that this is rarely the case (only two adaptions in the whole Isabelle
  3151 distribution).  INCOMPATIBILITY: rewrite proofs
  3152 
  3153 d) ML code directly refering to constant names
  3154 This in general only affects hand-written proof tactics, simprocs and
  3155 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3156 Consider using @{const_name} antiquotation.
  3157 
  3158 * New class "default" with associated constant "default".
  3159 
  3160 * Function "sgn" is now overloaded and available on int, real, complex
  3161 (and other numeric types), using class "sgn".  Two possible defs of
  3162 sgn are given as equational assumptions in the classes sgn_if and
  3163 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3164 INCOMPATIBILITY.
  3165 
  3166 * Locale "partial_order" now unified with class "order" (cf. theory
  3167 Orderings), added parameter "less".  INCOMPATIBILITY.
  3168 
  3169 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3170 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3171 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3172 
  3173 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3174 changed order of proof goals in instance proofs.
  3175 
  3176 * The transitivity reasoner for partial and linear orders is set up
  3177 for classes "order" and "linorder".  Instances of the reasoner are available
  3178 in all contexts importing or interpreting the corresponding locales.
  3179 Method "order" invokes the reasoner separately; the reasoner
  3180 is also integrated with the Simplifier as a solver.  Diagnostic
  3181 command 'print_orders' shows the available instances of the reasoner
  3182 in the current context.
  3183 
  3184 * Localized monotonicity predicate in theory "Orderings"; integrated
  3185 lemmas max_of_mono and min_of_mono with this predicate.
  3186 INCOMPATIBILITY.
  3187 
  3188 * Formulation of theorem "dense" changed slightly due to integration
  3189 with new class dense_linear_order.
  3190 
  3191 * Uniform lattice theory development in HOL.
  3192 
  3193     constants "meet" and "join" now named "inf" and "sup"
  3194     constant "Meet" now named "Inf"
  3195 
  3196     classes "meet_semilorder" and "join_semilorder" now named
  3197       "lower_semilattice" and "upper_semilattice"
  3198     class "lorder" now named "lattice"
  3199     class "comp_lat" now named "complete_lattice"
  3200 
  3201     Instantiation of lattice classes allows explicit definitions
  3202     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3203 
  3204   INCOMPATIBILITY.  Theorem renames:
  3205 
  3206     meet_left_le            ~> inf_le1
  3207     meet_right_le           ~> inf_le2
  3208     join_left_le            ~> sup_ge1
  3209     join_right_le           ~> sup_ge2
  3210     meet_join_le            ~> inf_sup_ord
  3211     le_meetI                ~> le_infI
  3212     join_leI                ~> le_supI
  3213     le_meet                 ~> le_inf_iff
  3214     le_join                 ~> ge_sup_conv
  3215     meet_idempotent         ~> inf_idem
  3216     join_idempotent         ~> sup_idem
  3217     meet_comm               ~> inf_commute
  3218     join_comm               ~> sup_commute
  3219     meet_leI1               ~> le_infI1
  3220     meet_leI2               ~> le_infI2
  3221     le_joinI1               ~> le_supI1
  3222     le_joinI2               ~> le_supI2
  3223     meet_assoc              ~> inf_assoc
  3224     join_assoc              ~> sup_assoc
  3225     meet_left_comm          ~> inf_left_commute
  3226     meet_left_idempotent    ~> inf_left_idem
  3227     join_left_comm          ~> sup_left_commute
  3228     join_left_idempotent    ~> sup_left_idem
  3229     meet_aci                ~> inf_aci
  3230     join_aci                ~> sup_aci
  3231     le_def_meet             ~> le_iff_inf
  3232     le_def_join             ~> le_iff_sup
  3233     join_absorp2            ~> sup_absorb2
  3234     join_absorp1            ~> sup_absorb1
  3235     meet_absorp1            ~> inf_absorb1
  3236     meet_absorp2            ~> inf_absorb2
  3237     meet_join_absorp        ~> inf_sup_absorb
  3238     join_meet_absorp        ~> sup_inf_absorb
  3239     distrib_join_le         ~> distrib_sup_le
  3240     distrib_meet_le         ~> distrib_inf_le
  3241 
  3242     add_meet_distrib_left   ~> add_inf_distrib_left
  3243     add_join_distrib_left   ~> add_sup_distrib_left
  3244     is_join_neg_meet        ~> is_join_neg_inf
  3245     is_meet_neg_join        ~> is_meet_neg_sup
  3246     add_meet_distrib_right  ~> add_inf_distrib_right
  3247     add_join_distrib_right  ~> add_sup_distrib_right
  3248     add_meet_join_distribs  ~> add_sup_inf_distribs
  3249     join_eq_neg_meet        ~> sup_eq_neg_inf
  3250     meet_eq_neg_join        ~> inf_eq_neg_sup
  3251     add_eq_meet_join        ~> add_eq_inf_sup
  3252     meet_0_imp_0            ~> inf_0_imp_0
  3253     join_0_imp_0            ~> sup_0_imp_0
  3254     meet_0_eq_0             ~> inf_0_eq_0
  3255     join_0_eq_0             ~> sup_0_eq_0
  3256     neg_meet_eq_join        ~> neg_inf_eq_sup
  3257     neg_join_eq_meet        ~> neg_sup_eq_inf
  3258     join_eq_if              ~> sup_eq_if
  3259 
  3260     mono_meet               ~> mono_inf
  3261     mono_join               ~> mono_sup
  3262     meet_bool_eq            ~> inf_bool_eq
  3263     join_bool_eq            ~> sup_bool_eq
  3264     meet_fun_eq             ~> inf_fun_eq
  3265     join_fun_eq             ~> sup_fun_eq
  3266     meet_set_eq             ~> inf_set_eq
  3267     join_set_eq             ~> sup_set_eq
  3268     meet1_iff               ~> inf1_iff
  3269     meet2_iff               ~> inf2_iff
  3270     meet1I                  ~> inf1I
  3271     meet2I                  ~> inf2I
  3272     meet1D1                 ~> inf1D1
  3273     meet2D1                 ~> inf2D1
  3274     meet1D2                 ~> inf1D2
  3275     meet2D2                 ~> inf2D2
  3276     meet1E                  ~> inf1E
  3277     meet2E                  ~> inf2E
  3278     join1_iff               ~> sup1_iff
  3279     join2_iff               ~> sup2_iff
  3280     join1I1                 ~> sup1I1
  3281     join2I1                 ~> sup2I1
  3282     join1I1                 ~> sup1I1
  3283     join2I2                 ~> sup1I2
  3284     join1CI                 ~> sup1CI
  3285     join2CI                 ~> sup2CI
  3286     join1E                  ~> sup1E
  3287     join2E                  ~> sup2E
  3288 
  3289     is_meet_Meet            ~> is_meet_Inf
  3290     Meet_bool_def           ~> Inf_bool_def
  3291     Meet_fun_def            ~> Inf_fun_def
  3292     Meet_greatest           ~> Inf_greatest
  3293     Meet_lower              ~> Inf_lower
  3294     Meet_set_def            ~> Inf_set_def
  3295 
  3296     Sup_def                 ~> Sup_Inf
  3297     Sup_bool_eq             ~> Sup_bool_def
  3298     Sup_fun_eq              ~> Sup_fun_def
  3299     Sup_set_eq              ~> Sup_set_def
  3300 
  3301     listsp_meetI            ~> listsp_infI
  3302     listsp_meet_eq          ~> listsp_inf_eq
  3303 
  3304     meet_min                ~> inf_min
  3305     join_max                ~> sup_max
  3306 
  3307 * Added syntactic class "size"; overloaded constant "size" now has
  3308 type "'a::size ==> bool"
  3309 
  3310 * Internal reorganisation of `size' of datatypes: size theorems
  3311 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3312 simplification rules by default!); theorems "prod.size" now named
  3313 "*.size".
  3314 
  3315 * Class "div" now inherits from class "times" rather than "type".
  3316 INCOMPATIBILITY.
  3317 
  3318 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  3319 Linorder etc.  have disappeared; operations defined in terms of
  3320 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  3321 
  3322 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  3323 
  3324 * HOL-Word: New extensive library and type for generic, fixed size
  3325 machine words, with arithemtic, bit-wise, shifting and rotating
  3326 operations, reflection into int, nat, and bool lists, automation for
  3327 linear arithmetic (by automatic reflection into nat or int), including
  3328 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  3329 arithmetic type classes, supporting automatic simplification of
  3330 numerals on all operations.
  3331 
  3332 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  3333 
  3334 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  3335 
  3336 * Code generator library theories:
  3337   - Code_Integer represents HOL integers by big integer literals in target
  3338     languages.
  3339   - Code_Char represents HOL characters by character literals in target
  3340     languages.
  3341   - Code_Char_chr like Code_Char, but also offers treatment of character
  3342     codes; includes Code_Integer.
  3343   - Executable_Set allows to generate code for finite sets using lists.
  3344   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  3345     denominator).
  3346   - Executable_Real implements a subset of real numbers, namly those
  3347     representable by rational numbers.
  3348   - Efficient_Nat implements natural numbers by integers, which in general will
  3349     result in higher efficency; pattern matching with 0/Suc is eliminated;
  3350     includes Code_Integer.
  3351   - Code_Index provides an additional datatype index which is mapped to
  3352     target-language built-in integers.
  3353   - Code_Message provides an additional datatype message_string which is isomorphic to
  3354     strings; messages are mapped to target-language strings.
  3355 
  3356 * New package for inductive predicates
  3357 
  3358   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  3359 
  3360     inductive
  3361       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3362       for z_1 :: U_1 and ... and z_n :: U_m
  3363     where
  3364       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3365     | ...
  3366 
  3367   with full support for type-inference, rather than
  3368 
  3369     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3370 
  3371     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3372     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3373 
  3374     inductive "s z_1 ... z_m"
  3375     intros
  3376       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3377       ...
  3378 
  3379   For backward compatibility, there is a wrapper allowing inductive
  3380   sets to be defined with the new package via
  3381 
  3382     inductive_set
  3383       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3384       for z_1 :: U_1 and ... and z_n :: U_m
  3385     where
  3386       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3387     | ...
  3388 
  3389   or
  3390 
  3391     inductive_set
  3392       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3393       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3394       for z_1 :: U_1 and ... and z_n :: U_m
  3395     where
  3396       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3397     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3398     | ...
  3399 
  3400   if the additional syntax "p ..." is required.
  3401 
  3402   Numerous examples can be found in the subdirectories src/HOL/Auth,
  3403   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  3404 
  3405   INCOMPATIBILITIES:
  3406 
  3407   - Since declaration and definition of inductive sets or predicates
  3408     is no longer separated, abbreviations involving the newly
  3409     introduced sets or predicates must be specified together with the
  3410     introduction rules after the 'where' keyword (see above), rather
  3411     than before the actual inductive definition.
  3412 
  3413   - The variables in induction and elimination rules are now
  3414     quantified in the order of their occurrence in the introduction
  3415     rules, rather than in alphabetical order. Since this may break
  3416     some proofs, these proofs either have to be repaired, e.g. by
  3417     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  3418     statements of the form
  3419 
  3420       case (rule_i a_i_1 ... a_i_{k_i})
  3421 
  3422     or the old order of quantification has to be restored by explicitly adding
  3423     meta-level quantifiers in the introduction rules, i.e.
  3424 
  3425       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  3426 
  3427   - The format of the elimination rules is now
  3428 
  3429       p z_1 ... z_m x_1 ... x_n ==>
  3430         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3431         ==> ... ==> P
  3432 
  3433     for predicates and
  3434 
  3435       (x_1, ..., x_n) : s z_1 ... z_m ==>
  3436         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3437         ==> ... ==> P
  3438 
  3439     for sets rather than
  3440 
  3441       x : s z_1 ... z_m ==>
  3442         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  3443         ==> ... ==> P
  3444 
  3445     This may require terms in goals to be expanded to n-tuples
  3446     (e.g. using case_tac or simplification with the split_paired_all
  3447     rule) before the above elimination rule is applicable.
  3448 
  3449   - The elimination or case analysis rules for (mutually) inductive
  3450     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  3451     list of rules "p_1_..._p_k.elims" is no longer available.
  3452 
  3453 * New package "function"/"fun" for general recursive functions,
  3454 supporting mutual and nested recursion, definitions in local contexts,
  3455 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  3456 for small examples, and the separate tutorial on the function
  3457 package. The old recdef "package" is still available as before, but
  3458 users are encouraged to use the new package.
  3459 
  3460 * Method "lexicographic_order" automatically synthesizes termination
  3461 relations as lexicographic combinations of size measures. 
  3462 
  3463 * Case-expressions allow arbitrary constructor-patterns (including
  3464 "_") and take their order into account, like in functional
  3465 programming.  Internally, this is translated into nested
  3466 case-expressions; missing cases are added and mapped to the predefined
  3467 constant "undefined". In complicated cases printing may no longer show
  3468 the original input but the internal form. Lambda-abstractions allow
  3469 the same form of pattern matching: "% pat1 => e1 | ..." is an
  3470 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  3471 variable.
  3472 
  3473 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  3474 is an abbreviation for "of_nat :: nat => int". The simplification
  3475 rules for "of_nat" have been changed to work like "int" did
  3476 previously.  Potential INCOMPATIBILITY:
  3477   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  3478   - of_nat_diff and of_nat_mult are no longer default simp rules
  3479 
  3480 * Method "algebra" solves polynomial equations over (semi)rings using
  3481 Groebner bases. The (semi)ring structure is defined by locales and the
  3482 tool setup depends on that generic context. Installing the method for
  3483 a specific type involves instantiating the locale and possibly adding
  3484 declarations for computation on the coefficients.  The method is
  3485 already instantiated for natural numbers and for the axiomatic class
  3486 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  3487 CALCULEMUS 2007 for the general principles underlying this
  3488 architecture of context-aware proof-tools.
  3489 
  3490 * Method "ferrack" implements quantifier elimination over
  3491 special-purpose dense linear orders using locales (analogous to
  3492 "algebra"). The method is already installed for class
  3493 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  3494 rat, etc.
  3495 
  3496 * Former constant "List.op @" now named "List.append".  Use ML
  3497 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  3498 circumvent possible incompatibilities when working on ML level.
  3499 
  3500 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  3501 
  3502 * New function listsum :: 'a list => 'a for arbitrary monoids.
  3503 Special syntax: "SUM x <- xs. f x" (and latex variants)
  3504 
  3505 * New syntax for Haskell-like list comprehension (input only), eg.
  3506 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  3507 
  3508 * The special syntax for function "filter" has changed from [x :
  3509 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  3510 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  3511 
  3512 * [a..b] is now defined for arbitrary linear orders.  It used to be
  3513 defined on nat only, as an abbreviation for [a..<Suc b]
  3514 INCOMPATIBILITY.
  3515 
  3516 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  3517 
  3518 * New functions "sorted" and "sort" in src/HOL/List.thy.
  3519 
  3520 * New lemma collection field_simps (an extension of ring_simps) for
  3521 manipulating (in)equations involving division. Multiplies with all
  3522 denominators that can be proved to be non-zero (in equations) or
  3523 positive/negative (in inequations).
  3524 
  3525 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  3526 have been improved and renamed to ring_simps, group_simps and
  3527 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  3528 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  3529 
  3530 * Theory Library/Commutative_Ring: switched from recdef to function
  3531 package; constants add, mul, pow now curried.  Infix syntax for
  3532 algebraic operations.
  3533 
  3534 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  3535 INCOMPATIBILITY.
  3536 
  3537 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  3538 INCOMPATIBILITY.
  3539 
  3540 * HOL/records: generalised field-update to take a function on the
  3541 field rather than the new value: r(|A := x|) is translated to A_update
  3542 (K x) r The K-combinator that is internally used is called K_record.
  3543 INCOMPATIBILITY: Usage of the plain update functions has to be
  3544 adapted.
  3545  
  3546 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  3547 * x = 0, which are required for a semiring.  Richer structures do not
  3548 inherit from semiring_0 anymore, because this property is a theorem
  3549 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  3550 there is more to prove, but this is mostly trivial.
  3551 
  3552 * Class "recpower" is generalized to arbitrary monoids, not just
  3553 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  3554 commutativity or semiring properties additionally.
  3555 
  3556 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  3557 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  3558 better use 'abbreviation'.
  3559 
  3560 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  3561 
  3562 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  3563 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  3564 significant changes for setting up numeral syntax for types:
  3565   - New constants Numeral.pred and Numeral.succ instead
  3566       of former Numeral.bin_pred and Numeral.bin_succ.
  3567   - Use integer operations instead of bin_add, bin_mult and so on.
  3568   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  3569   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  3570 
  3571 See src/HOL/Integ/IntArith.thy for an example setup.
  3572 
  3573 * Command 'normal_form' computes the normal form of a term that may
  3574 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  3575 produces ``[b, c, a]'' (without proof).  This command is suitable for
  3576 heavy-duty computations because the functions are compiled to ML
  3577 first.  Correspondingly, a method "normalization" is provided.  See
  3578 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  3579 
  3580 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  3581 25 like -->); output depends on the "iff" print_mode, the default is
  3582 "A = B" (with priority 50).
  3583 
  3584 * Relations less (<) and less_eq (<=) are also available on type bool.
  3585 Modified syntax to disallow nesting without explicit parentheses,
  3586 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  3587 INCOMPATIBILITY.
  3588 
  3589 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  3590 
  3591 * Relation composition operator "op O" now has precedence 75 and binds
  3592 stronger than union and intersection. INCOMPATIBILITY.
  3593 
  3594 * The old set interval syntax "{m..n(}" (and relatives) has been
  3595 removed.  Use "{m..<n}" (and relatives) instead.
  3596 
  3597 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  3598 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  3599 ``declare [[simproc del: neq]]''.
  3600 
  3601 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  3602 True/False.
  3603 
  3604 * Theorem Cons_eq_map_conv no longer declared as "simp".
  3605 
  3606 * Theorem setsum_mult renamed to setsum_right_distrib.
  3607 
  3608 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  3609 ``rule'' method.
  3610 
  3611 * Reimplemented methods "sat" and "satx", with several improvements:
  3612 goals no longer need to be stated as "<prems> ==> False", equivalences
  3613 (i.e. "=" on type bool) are handled, variable names of the form
  3614 "lit_<n>" are no longer reserved, significant speedup.
  3615 
  3616 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  3617 zChaff is still supported as well.
  3618 
  3619 * 'inductive' and 'datatype': provide projections of mutual rules,
  3620 bundled as foo_bar.inducts;
  3621 
  3622 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  3623 Library.
  3624 
  3625 * Library: moved theory Accessible_Part to main HOL.
  3626 
  3627 * Library: added theory Coinductive_List of potentially infinite lists
  3628 as greatest fixed-point.
  3629 
  3630 * Library: added theory AssocList which implements (finite) maps as
  3631 association lists.
  3632 
  3633 * Method "evaluation" solves goals (i.e. a boolean expression)
  3634 efficiently by compiling it to ML.  The goal is "proved" (via an
  3635 oracle) if it evaluates to True.
  3636 
  3637 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  3638 also when invoked by the simplifier.  This results in the Simplifier
  3639 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  3640 Configuration option fast_arith_split_limit=0 recovers the old
  3641 behavior.
  3642 
  3643 * Support for hex (0x20) and binary (0b1001) numerals.
  3644 
  3645 * New method: reify eqs (t), where eqs are equations for an
  3646 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  3647 parameter, computes a term s::'b and a list xs::'a list and proves the
  3648 theorem I xs s = t. This is also known as reification or quoting. The
  3649 resulting theorem is applied to the subgoal to substitute t with I xs
  3650 s.  If t is omitted, the subgoal itself is reified.
  3651 
  3652 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  3653 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  3654 where f is supposed to be a computable function (in the sense of code
  3655 generattion). The method uses reify to compute s and xs as above then
  3656 applies corr_thm and uses normalization by evaluation to "prove" f s =
  3657 r and finally gets the theorem t = r, which is again applied to the
  3658 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  3659 
  3660 * Reflection: Automatic reification now handels binding, an example is
  3661 available in src/HOL/ex/ReflectionEx.thy
  3662 
  3663 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  3664 command 'statespace' that is similar to 'record', but introduces an
  3665 abstract specification based on the locale infrastructure instead of
  3666 HOL types.  This leads to extra flexibility in composing state spaces,
  3667 in particular multiple inheritance and renaming of components.
  3668 
  3669 
  3670 *** HOL-Complex ***
  3671 
  3672 * Hyperreal: Functions root and sqrt are now defined on negative real
  3673 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  3674 Nonnegativity side conditions have been removed from many lemmas, so
  3675 that more subgoals may now be solved by simplification; potential
  3676 INCOMPATIBILITY.
  3677 
  3678 * Real: new type classes formalize real normed vector spaces and
  3679 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  3680 and norm :: 'a => real.
  3681 
  3682 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  3683 reals into other types. The overloaded constant Reals :: 'a set is now
  3684 defined as range of_real; potential INCOMPATIBILITY.
  3685 
  3686 * Real: proper support for ML code generation, including 'quickcheck'.
  3687 Reals are implemented as arbitrary precision rationals.
  3688 
  3689 * Hyperreal: Several constants that previously worked only for the
  3690 reals have been generalized, so they now work over arbitrary vector
  3691 spaces. Type annotations may need to be added in some cases; potential
  3692 INCOMPATIBILITY.
  3693 
  3694   Infinitesimal  :: ('a::real_normed_vector) star set
  3695   HFinite        :: ('a::real_normed_vector) star set
  3696   HInfinite      :: ('a::real_normed_vector) star set
  3697   approx         :: ('a::real_normed_vector) star => 'a star => bool
  3698   monad          :: ('a::real_normed_vector) star => 'a star set
  3699   galaxy         :: ('a::real_normed_vector) star => 'a star set
  3700   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  3701   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  3702   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  3703   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  3704   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  3705   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  3706   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  3707   sgn            :: 'a::real_normed_vector => 'a
  3708   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  3709 
  3710 * Complex: Some complex-specific constants are now abbreviations for
  3711 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  3712 hnorm.  Other constants have been entirely removed in favor of the
  3713 polymorphic versions (INCOMPATIBILITY):
  3714 
  3715   approx        <-- capprox
  3716   HFinite       <-- CFinite
  3717   HInfinite     <-- CInfinite
  3718   Infinitesimal <-- CInfinitesimal
  3719   monad         <-- cmonad
  3720   galaxy        <-- cgalaxy
  3721   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  3722   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  3723   (ns)deriv     <-- (ns)cderiv
  3724 
  3725 
  3726 *** HOL-Algebra ***
  3727 
  3728 * Formalisation of ideals and the quotient construction over rings.
  3729 
  3730 * Order and lattice theory no longer based on records.
  3731 INCOMPATIBILITY.
  3732 
  3733 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  3734 greatest_closed.  INCOMPATIBILITY.
  3735 
  3736 * Method algebra is now set up via an attribute.  For examples see
  3737 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  3738 of algebraic structures.
  3739 
  3740 * Renamed theory CRing to Ring.
  3741 
  3742 
  3743 *** HOL-Nominal ***
  3744 
  3745 * Substantial, yet incomplete support for nominal datatypes (binding
  3746 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  3747 src/HOL/Nominal/Examples.  Prospective users should consult
  3748 http://isabelle.in.tum.de/nominal/
  3749 
  3750 
  3751 *** ML ***
  3752 
  3753 * ML basics: just one true type int, which coincides with IntInf.int
  3754 (even on SML/NJ).
  3755 
  3756 * ML within Isar: antiquotations allow to embed statically-checked
  3757 formal entities in the source, referring to the context available at
  3758 compile-time.  For example:
  3759 
  3760 ML {* @{sort "{zero,one}"} *}
  3761 ML {* @{typ "'a => 'b"} *}
  3762 ML {* @{term "%x. x"} *}
  3763 ML {* @{prop "x == y"} *}
  3764 ML {* @{ctyp "'a => 'b"} *}
  3765 ML {* @{cterm "%x. x"} *}
  3766 ML {* @{cprop "x == y"} *}
  3767 ML {* @{thm asm_rl} *}
  3768 ML {* @{thms asm_rl} *}
  3769 ML {* @{type_name c} *}
  3770 ML {* @{type_syntax c} *}
  3771 ML {* @{const_name c} *}
  3772 ML {* @{const_syntax c} *}
  3773 ML {* @{context} *}
  3774 ML {* @{theory} *}
  3775 ML {* @{theory Pure} *}
  3776 ML {* @{theory_ref} *}
  3777 ML {* @{theory_ref Pure} *}
  3778 ML {* @{simpset} *}
  3779 ML {* @{claset} *}
  3780 ML {* @{clasimpset} *}
  3781 
  3782 The same works for sources being ``used'' within an Isar context.
  3783 
  3784 * ML in Isar: improved error reporting; extra verbosity with
  3785 ML_Context.trace enabled.
  3786 
  3787 * Pure/General/table.ML: the join operations now works via exceptions
  3788 DUP/SAME instead of type option. This is simpler in simple cases, and
  3789 admits slightly more efficient complex applications.
  3790 
  3791 * Pure: 'advanced' translation functions (parse_translation etc.) now
  3792 use Context.generic instead of just theory.
  3793 
  3794 * Pure: datatype Context.generic joins theory/Proof.context and
  3795 provides some facilities for code that works in either kind of
  3796 context, notably GenericDataFun for uniform theory and proof data.
  3797 
  3798 * Pure: simplified internal attribute type, which is now always
  3799 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  3800 local (Proof.context) attributes have been discontinued, while
  3801 minimizing code duplication. Thm.rule_attribute and
  3802 Thm.declaration_attribute build canonical attributes; see also structure
  3803 Context for further operations on Context.generic, notably
  3804 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  3805 declarations and definitions.
  3806 
  3807 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  3808 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  3809 init only required for impure data. INCOMPATIBILITY: empty really need
  3810 to be empty (no dependencies on theory content!)
  3811 
  3812 * Pure/kernel: consts certification ignores sort constraints given in
  3813 signature declarations. (This information is not relevant to the
  3814 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  3815 potential INCOMPATIBILITY.
  3816 
  3817 * Pure: axiomatic type classes are now purely definitional, with
  3818 explicit proofs of class axioms and super class relations performed
  3819 internally. See Pure/axclass.ML for the main internal interfaces --
  3820 notably AxClass.define_class supercedes AxClass.add_axclass, and
  3821 AxClass.axiomatize_class/classrel/arity supersede
  3822 Sign.add_classes/classrel/arities.
  3823 
  3824 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  3825 global/local versions on theory vs. Proof.context have been
  3826 discontinued; Attrib.syntax and Method.syntax have been adapted
  3827 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  3828 attributes, methods, etc.
  3829 
  3830 * Pure: several functions of signature "... -> theory -> theory * ..."
  3831 have been reoriented to "... -> theory -> ... * theory" in order to
  3832 allow natural usage in combination with the ||>, ||>>, |-> and
  3833 fold_map combinators.
  3834 
  3835 * Pure: official theorem names (closed derivations) and additional
  3836 comments (tags) are now strictly separate.  Name hints -- which are
  3837 maintained as tags -- may be attached any time without affecting the
  3838 derivation.
  3839 
  3840 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  3841 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  3842 achieve the old behaviour.
  3843 
  3844 * Pure: the "Goal" constant is now called "prop", supporting a
  3845 slightly more general idea of ``protecting'' meta-level rule
  3846 statements.
  3847 
  3848 * Pure: Logic.(un)varify only works in a global context, which is now
  3849 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  3850 Logic.legacy_(un)varify as temporary workaround.
  3851 
  3852 * Pure: structure Name provides scalable operations for generating
  3853 internal variable names, notably Name.variants etc.  This replaces
  3854 some popular functions from term.ML:
  3855 
  3856   Term.variant		->  Name.variant
  3857   Term.variantlist	->  Name.variant_list
  3858   Term.invent_names	->  Name.invent_list
  3859 
  3860 Note that low-level renaming rarely occurs in new code -- operations
  3861 from structure Variable are used instead (see below).
  3862 
  3863 * Pure: structure Variable provides fundamental operations for proper
  3864 treatment of fixed/schematic variables in a context.  For example,
  3865 Variable.import introduces fixes for schematics of given facts and
  3866 Variable.export reverses the effect (up to renaming) -- this replaces
  3867 various freeze_thaw operations.
  3868 
  3869 * Pure: structure Goal provides simple interfaces for
  3870 init/conclude/finish and tactical prove operations (replacing former
  3871 Tactic.prove).  Goal.prove is the canonical way to prove results
  3872 within a given context; Goal.prove_global is a degraded version for
  3873 theory level goals, including a global Drule.standard.  Note that
  3874 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  3875 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  3876 in a locale context).
  3877 
  3878 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  3879 and type checking (Syntax.check_term etc.), with common combinations
  3880 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  3881 which are considered legacy and await removal.
  3882 
  3883 * Pure/Syntax: generic interfaces for type unchecking
  3884 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  3885 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  3886 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  3887 available for convenience, but refer to the very same operations using
  3888 a mere theory instead of a full context.
  3889 
  3890 * Isar: simplified treatment of user-level errors, using exception
  3891 ERROR of string uniformly.  Function error now merely raises ERROR,
  3892 without any side effect on output channels.  The Isar toplevel takes
  3893 care of proper display of ERROR exceptions.  ML code may use plain
  3894 handle/can/try; cat_error may be used to concatenate errors like this:
  3895 
  3896   ... handle ERROR msg => cat_error msg "..."
  3897 
  3898 Toplevel ML code (run directly or through the Isar toplevel) may be
  3899 embedded into the Isar toplevel with exception display/debug like
  3900 this:
  3901 
  3902   Isar.toplevel (fn () => ...)
  3903 
  3904 INCOMPATIBILITY, removed special transform_error facilities, removed
  3905 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  3906 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  3907 -- use plain ERROR instead.
  3908 
  3909 * Isar: theory setup now has type (theory -> theory), instead of a
  3910 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  3911 
  3912 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  3913 ProofContext.debug/verbose flags.
  3914 
  3915 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  3916 theory before entering a proof state.  Transactions now always see a
  3917 quasi-functional intermediate checkpoint, both in interactive and
  3918 batch mode.
  3919 
  3920 * Isar: simplified interfaces for outer syntax.  Renamed
  3921 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  3922 OuterSyntax.add_parsers -- this functionality is now included in
  3923 OuterSyntax.command etc.  INCOMPATIBILITY.
  3924 
  3925 * Simplifier: the simpset of a running simplification process now
  3926 contains a proof context (cf. Simplifier.the_context), which is the
  3927 very context that the initial simpset has been retrieved from (by
  3928 simpset_of/local_simpset_of).  Consequently, all plug-in components
  3929 (solver, looper etc.) may depend on arbitrary proof data.
  3930 
  3931 * Simplifier.inherit_context inherits the proof context (plus the
  3932 local bounds) of the current simplification process; any simproc
  3933 etc. that calls the Simplifier recursively should do this!  Removed
  3934 former Simplifier.inherit_bounds, which is already included here --
  3935 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  3936 specify an explicit context using Simplifier.context/theory_context.
  3937 
  3938 * Simplifier/Classical Reasoner: more abstract interfaces
  3939 change_simpset/claset for modifying the simpset/claset reference of a
  3940 theory; raw versions simpset/claset_ref etc. have been discontinued --
  3941 INCOMPATIBILITY.
  3942 
  3943 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  3944 "Trueprop" etc.
  3945 
  3946 
  3947 *** System ***
  3948 
  3949 * settings: the default heap location within ISABELLE_HOME_USER now
  3950 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  3951 Isabelle installations.
  3952 
  3953 * isabelle-process: option -S (secure mode) disables some critical
  3954 operations, notably runtime compilation and evaluation of ML source
  3955 code.
  3956 
  3957 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  3958 
  3959 * Support for parallel execution, using native multicore support of
  3960 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  3961 independent theories, according to the given theory header
  3962 specifications. The maximum number of worker threads is specified via
  3963 usedir option -M or the "max-threads" setting in Proof General. A
  3964 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  3965 to 6 on a 8-core machine.  User-code needs to observe certain
  3966 guidelines for thread-safe programming, see appendix A in the Isar
  3967 Implementation manual.
  3968 
  3969 
  3970 
  3971 New in Isabelle2005 (October 2005)
  3972 ----------------------------------
  3973 
  3974 *** General ***
  3975 
  3976 * Theory headers: the new header syntax for Isar theories is
  3977 
  3978   theory <name>
  3979   imports <theory1> ... <theoryN>
  3980   uses <file1> ... <fileM>
  3981   begin
  3982 
  3983 where the 'uses' part is optional.  The previous syntax
  3984 
  3985   theory <name> = <theory1> + ... + <theoryN>:
  3986 
  3987 will disappear in the next release.  Use isatool fixheaders to convert
  3988 existing theory files.  Note that there is no change in ancient
  3989 non-Isar theories now, but these will disappear soon.
  3990 
  3991 * Theory loader: parent theories can now also be referred to via
  3992 relative and absolute paths.
  3993 
  3994 * Command 'find_theorems' searches for a list of criteria instead of a
  3995 list of constants. Known criteria are: intro, elim, dest, name:string,
  3996 simp:term, and any term. Criteria can be preceded by '-' to select
  3997 theorems that do not match. Intro, elim, dest select theorems that
  3998 match the current goal, name:s selects theorems whose fully qualified
  3999 name contain s, and simp:term selects all simplification rules whose
  4000 lhs match term.  Any other term is interpreted as pattern and selects
  4001 all theorems matching the pattern. Available in ProofGeneral under
  4002 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4003 
  4004   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4005 
  4006 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4007 matching the current goal as introduction rule and not having "HOL."
  4008 in their name (i.e. not being defined in theory HOL).
  4009 
  4010 * Command 'thms_containing' has been discontinued in favour of
  4011 'find_theorems'; INCOMPATIBILITY.
  4012 
  4013 * Communication with Proof General is now 8bit clean, which means that
  4014 Unicode text in UTF-8 encoding may be used within theory texts (both
  4015 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4016 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4017 
  4018   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4019   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4020 
  4021 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4022 Classical Reasoner.  Typical big applications run around 2 times
  4023 faster.
  4024 
  4025 
  4026 *** Document preparation ***
  4027 
  4028 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4029 of raw sources.  Only those symbols that do not require additional
  4030 LaTeX packages (depending on comments in isabellesym.sty) are
  4031 displayed properly, everything else is left verbatim.  isatool display
  4032 and isatool print are used as front ends (these are subject to the
  4033 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4034 
  4035 * Command tags control specific markup of certain regions of text,
  4036 notably folding and hiding.  Predefined tags include "theory" (for
  4037 theory begin and end), "proof" for proof commands, and "ML" for
  4038 commands involving ML code; the additional tags "visible" and
  4039 "invisible" are unused by default.  Users may give explicit tag
  4040 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4041 interpretation of tags is determined by the LaTeX job during document
  4042 preparation: see option -V of isatool usedir, or options -n and -t of
  4043 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4044 \isadroptag.
  4045 
  4046 Several document versions may be produced at the same time via isatool
  4047 usedir (the generated index.html will link all of them).  Typical
  4048 specifications include ''-V document=theory,proof,ML'' to present
  4049 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4050 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4051 these parts without any formal replacement text.  The Isabelle site
  4052 default settings produce ''document'' and ''outline'' versions as
  4053 specified above.
  4054 
  4055 * Several new antiquotations:
  4056 
  4057   @{term_type term} prints a term with its type annotated;
  4058 
  4059   @{typeof term} prints the type of a term;
  4060 
  4061   @{const const} is the same as @{term const}, but checks that the
  4062   argument is a known logical constant;
  4063 
  4064   @{term_style style term} and @{thm_style style thm} print a term or
  4065   theorem applying a "style" to it
  4066 
  4067   @{ML text}
  4068 
  4069 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4070 definitions, equations, inequations etc., 'concl' printing only the
  4071 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4072 to print the specified premise.  TermStyle.add_style provides an ML
  4073 interface for introducing further styles.  See also the "LaTeX Sugar"
  4074 document practical applications.  The ML antiquotation prints
  4075 type-checked ML expressions verbatim.
  4076 
  4077 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4078 and 'text' support optional locale specification '(in loc)', which
  4079 specifies the default context for interpreting antiquotations.  For
  4080 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4081 
  4082 * Option 'locale=NAME' of antiquotations specifies an alternative
  4083 context interpreting the subsequent argument.  For example: @{thm
  4084 [locale=lattice] inf_assoc}.
  4085 
  4086 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4087 a proof context.
  4088 
  4089 * Proper output of antiquotations for theory commands involving a
  4090 proof context (such as 'locale' or 'theorem (in loc) ...').
  4091 
  4092 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4093 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4094 
  4095 * isatool usedir: new option -C (default true) controls whether option
  4096 -D should include a copy of the original document directory; -C false
  4097 prevents unwanted effects such as copying of administrative CVS data.
  4098 
  4099 
  4100 *** Pure ***
  4101 
  4102 * Considerably improved version of 'constdefs' command.  Now performs
  4103 automatic type-inference of declared constants; additional support for
  4104 local structure declarations (cf. locales and HOL records), see also
  4105 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4106 sequential dependencies of definitions within a single 'constdefs'
  4107 section; moreover, the declared name needs to be an identifier.  If
  4108 all fails, consider to fall back on 'consts' and 'defs' separately.
  4109 
  4110 * Improved indexed syntax and implicit structures.  First of all,
  4111 indexed syntax provides a notational device for subscripted
  4112 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4113 expressions.  Secondly, in a local context with structure
  4114 declarations, number indexes \<^sub>n or the empty index (default
  4115 number 1) refer to a certain fixed variable implicitly; option
  4116 show_structs controls printing of implicit structures.  Typical
  4117 applications of these concepts involve record types and locales.
  4118 
  4119 * New command 'no_syntax' removes grammar declarations (and
  4120 translations) resulting from the given syntax specification, which is
  4121 interpreted in the same manner as for the 'syntax' command.
  4122 
  4123 * 'Advanced' translation functions (parse_translation etc.) may depend
  4124 on the signature of the theory context being presently used for
  4125 parsing/printing, see also isar-ref manual.
  4126 
  4127 * Improved 'oracle' command provides a type-safe interface to turn an
  4128 ML expression of type theory -> T -> term into a primitive rule of
  4129 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4130 is already included here); see also FOL/ex/IffExample.thy;
  4131 INCOMPATIBILITY.
  4132 
  4133 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4134 before); "cI" is no longer bound, use "c.intro" instead.
  4135 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4136 axclasses vs. locales.
  4137 
  4138 * Improved internal renaming of symbolic identifiers -- attach primes
  4139 instead of base 26 numbers.
  4140 
  4141 * New flag show_question_marks controls printing of leading question
  4142 marks in schematic variable names.
  4143 
  4144 * In schematic variable names, *any* symbol following \<^isub> or
  4145 \<^isup> is now treated as part of the base name.  For example, the
  4146 following works without printing of awkward ".0" indexes:
  4147 
  4148   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4149     by simp
  4150 
  4151 * Inner syntax includes (*(*nested*) comments*).
  4152 
  4153 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4154 annotations as "(00...)".
  4155 
  4156 * Clear separation of logical types and nonterminals, where the latter
  4157 may only occur in 'syntax' specifications or type abbreviations.
  4158 Before that distinction was only partially implemented via type class
  4159 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4160 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4161 exotic syntax specifications may require further adaption
  4162 (e.g. Cube/Cube.thy).
  4163 
  4164 * Removed obsolete type class "logic", use the top sort {} instead.
  4165 Note that non-logical types should be declared as 'nonterminals'
  4166 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4167 specifications.
  4168 
  4169 * Attributes 'induct' and 'cases': type or set names may now be
  4170 locally fixed variables as well.
  4171 
  4172 * Simplifier: can now control the depth to which conditional rewriting
  4173 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4174 Limit.
  4175 
  4176 * Simplifier: simplification procedures may now take the current
  4177 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4178 interface), which is very useful for calling the Simplifier
  4179 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4180 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4181 low-level mk_simproc no longer applies Logic.varify internally, to
  4182 allow for use in a context of fixed variables.
  4183 
  4184 * thin_tac now works even if the assumption being deleted contains !!
  4185 or ==>.  More generally, erule now works even if the major premise of
  4186 the elimination rule contains !! or ==>.
  4187 
  4188 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4189 
  4190 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4191 from Pure, which contains all common declarations already.  Both
  4192 theories are defined via plain Isabelle/Isar .thy files.
  4193 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4194 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4195 use isatool fixcpure to adapt your theory and ML sources.
  4196 
  4197 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4198 selections of theorems in named facts via index ranges.
  4199 
  4200 * 'print_theorems': in theory mode, really print the difference
  4201 wrt. the last state (works for interactive theory development only),
  4202 in proof mode print all local facts (cf. 'print_facts');
  4203 
  4204 * 'hide': option '(open)' hides only base names.
  4205 
  4206 * More efficient treatment of intermediate checkpoints in interactive
  4207 theory development.
  4208 
  4209 * Code generator is now invoked via code_module (incremental code
  4210 generation) and code_library (modular code generation, ML structures
  4211 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4212 must be quoted when used as identifiers.
  4213 
  4214 * New 'value' command for reading, evaluating and printing terms using
  4215 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4216 quoted when used as identifier.
  4217 
  4218 
  4219 *** Locales ***
  4220 
  4221 * New commands for the interpretation of locale expressions in
  4222 theories (1), locales (2) and proof contexts (3).  These generate
  4223 proof obligations from the expression specification.  After the
  4224 obligations have been discharged, theorems of the expression are added
  4225 to the theory, target locale or proof context.  The synopsis of the
  4226 commands is a follows:
  4227 
  4228   (1) interpretation expr inst
  4229   (2) interpretation target < expr
  4230   (3) interpret expr inst
  4231 
  4232 Interpretation in theories and proof contexts require a parameter
  4233 instantiation of terms from the current context.  This is applied to
  4234 specifications and theorems of the interpreted expression.
  4235 Interpretation in locales only permits parameter renaming through the
  4236 locale expression.  Interpretation is smart in that interpretations
  4237 that are active already do not occur in proof obligations, neither are
  4238 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4239 inspect active interpretations of a particular locale.  For details,
  4240 see the Isar Reference manual.  Examples can be found in
  4241 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4242 
  4243 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4244 'interpret' instead.
  4245 
  4246 * New context element 'constrains' for adding type constraints to
  4247 parameters.
  4248 
  4249 * Context expressions: renaming of parameters with syntax
  4250 redeclaration.
  4251 
  4252 * Locale declaration: 'includes' disallowed.
  4253 
  4254 * Proper static binding of attribute syntax -- i.e. types / terms /
  4255 facts mentioned as arguments are always those of the locale definition
  4256 context, independently of the context of later invocations.  Moreover,
  4257 locale operations (renaming and type / term instantiation) are applied
  4258 to attribute arguments as expected.
  4259 
  4260 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4261 actual attributes; rare situations may require Attrib.attribute to
  4262 embed those attributes into Attrib.src that lack concrete syntax.
  4263 Attribute implementations need to cooperate properly with the static
  4264 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4265 Attrib.XXX_thm etc. already do the right thing without further
  4266 intervention.  Only unusual applications -- such as "where" or "of"
  4267 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4268 on the context and the facts involved -- may have to assign parsed
  4269 values to argument tokens explicitly.
  4270 
  4271 * Changed parameter management in theorem generation for long goal
  4272 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4273 theorem statement in rare situations.
  4274 
  4275 * Locale inspection command 'print_locale' omits notes elements.  Use
  4276 'print_locale!' to have them included in the output.
  4277 
  4278 
  4279 *** Provers ***
  4280 
  4281 * Provers/hypsubst.ML: improved version of the subst method, for
  4282 single-step rewriting: it now works in bound variable contexts. New is
  4283 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4284 rewrite a different subterm than the original subst method, which is
  4285 still available as 'simplesubst'.
  4286 
  4287 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4288 and quasi orders.
  4289 
  4290 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4291 reflexive-transitive closure of relations.
  4292 
  4293 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4294 limit (previously hard-coded with a value of 20) user-definable.
  4295 
  4296 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4297 is peformed already.  Object-logics merely need to finish their
  4298 initial simpset configuration as before.  INCOMPATIBILITY.
  4299 
  4300 
  4301 *** HOL ***
  4302 
  4303 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4304 
  4305   syntax (epsilon)
  4306     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4307 
  4308 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4309 and x-symbol; use option '-m epsilon' to get it actually printed.
  4310 Moreover, the mathematically important symbolic identifier \<epsilon>
  4311 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4312 
  4313 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  4314 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  4315 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  4316 support corresponding Isar calculations.
  4317 
  4318 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  4319 instead of ":".
  4320 
  4321 * theory SetInterval: changed the syntax for open intervals:
  4322 
  4323   Old       New
  4324   {..n(}    {..<n}
  4325   {)n..}    {n<..}
  4326   {m..n(}   {m..<n}
  4327   {)m..n}   {m<..n}
  4328   {)m..n(}  {m<..<n}
  4329 
  4330 The old syntax is still supported but will disappear in the next
  4331 release.  For conversion use the following Emacs search and replace
  4332 patterns (these are not perfect but work quite well):
  4333 
  4334   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  4335   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  4336 
  4337 * Theory Commutative_Ring (in Library): method comm_ring for proving
  4338 equalities in commutative rings; method 'algebra' provides a generic
  4339 interface.
  4340 
  4341 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  4342 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  4343 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  4344 be a tuple pattern.
  4345 
  4346 Some new syntax forms are available:
  4347 
  4348   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  4349   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  4350   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  4351   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  4352 
  4353 The latter form "\<Sum>x < k. e" used to be based on a separate
  4354 function "Summation", which has been discontinued.
  4355 
  4356 * theory Finite_Set: in structured induction proofs, the insert case
  4357 is now 'case (insert x F)' instead of the old counterintuitive 'case
  4358 (insert F x)'.
  4359 
  4360 * The 'refute' command has been extended to support a much larger
  4361 fragment of HOL, including axiomatic type classes, constdefs and
  4362 typedefs, inductive datatypes and recursion.
  4363 
  4364 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  4365 Requires zChaff with proof generation to be installed.  See
  4366 HOL/ex/SAT_Examples.thy for examples.
  4367 
  4368 * Datatype induction via method 'induct' now preserves the name of the
  4369 induction variable. For example, when proving P(xs::'a list) by
  4370 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  4371 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  4372 in unstructured proof scripts.
  4373 
  4374 * Reworked implementation of records.  Improved scalability for
  4375 records with many fields, avoiding performance problems for type
  4376 inference. Records are no longer composed of nested field types, but
  4377 of nested extension types. Therefore the record type only grows linear
  4378 in the number of extensions and not in the number of fields.  The
  4379 top-level (users) view on records is preserved.  Potential
  4380 INCOMPATIBILITY only in strange cases, where the theory depends on the
  4381 old record representation. The type generated for a record is called
  4382 <record_name>_ext_type.
  4383 
  4384 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  4385 proofs triggered by a record definition or a simproc (if
  4386 quick_and_dirty is enabled).  Definitions of large records can take
  4387 quite long.
  4388 
  4389 New simproc record_upd_simproc for simplification of multiple record
  4390 updates enabled by default.  Moreover, trivial updates are also
  4391 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  4392 occasionally, since simplification is more powerful by default.
  4393 
  4394 * typedef: proper support for polymorphic sets, which contain extra
  4395 type-variables in the term.
  4396 
  4397 * Simplifier: automatically reasons about transitivity chains
  4398 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  4399 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  4400 old proofs break occasionally as simplification may now solve more
  4401 goals than previously.
  4402 
  4403 * Simplifier: converts x <= y into x = y if assumption y <= x is
  4404 present.  Works for all partial orders (class "order"), in particular
  4405 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  4406 just like y <= x.
  4407 
  4408 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  4409 bound variable or a constant then the let is unfolded.  Otherwise
  4410 first a is simplified to b, and then f b is simplified to g. If
  4411 possible we abstract b from g arriving at "let x = b in h x",
  4412 otherwise we unfold the let and arrive at g.  The simproc can be
  4413 enabled/disabled by the reference use_let_simproc.  Potential
  4414 INCOMPATIBILITY since simplification is more powerful by default.
  4415 
  4416 * Classical reasoning: the meson method now accepts theorems as arguments.
  4417 
  4418 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  4419 jobs to provide advice on the provability of subgoals.
  4420 
  4421 * Theory OrderedGroup and Ring_and_Field: various additions and
  4422 improvements to faciliate calculations involving equalities and
  4423 inequalities.
  4424 
  4425 The following theorems have been eliminated or modified
  4426 (INCOMPATIBILITY):
  4427 
  4428   abs_eq             now named abs_of_nonneg
  4429   abs_of_ge_0        now named abs_of_nonneg
  4430   abs_minus_eq       now named abs_of_nonpos
  4431   imp_abs_id         now named abs_of_nonneg
  4432   imp_abs_neg_id     now named abs_of_nonpos
  4433   mult_pos           now named mult_pos_pos
  4434   mult_pos_le        now named mult_nonneg_nonneg
  4435   mult_pos_neg_le    now named mult_nonneg_nonpos
  4436   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  4437   mult_neg           now named mult_neg_neg
  4438   mult_neg_le        now named mult_nonpos_nonpos
  4439 
  4440 * The following lemmas in Ring_and_Field have been added to the simplifier:
  4441      
  4442      zero_le_square
  4443      not_square_less_zero 
  4444 
  4445   The following lemmas have been deleted from Real/RealPow:
  4446   
  4447      realpow_zero_zero
  4448      realpow_two
  4449      realpow_less
  4450      zero_le_power
  4451      realpow_two_le
  4452      abs_realpow_two
  4453      realpow_two_abs     
  4454 
  4455 * Theory Parity: added rules for simplifying exponents.
  4456 
  4457 * Theory List:
  4458 
  4459 The following theorems have been eliminated or modified
  4460 (INCOMPATIBILITY):
  4461 
  4462   list_all_Nil       now named list_all.simps(1)
  4463   list_all_Cons      now named list_all.simps(2)
  4464   list_all_conv      now named list_all_iff
  4465   set_mem_eq         now named mem_iff
  4466 
  4467 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  4468 asymptotic "big O" calculations.  See the notes in BigO.thy.
  4469 
  4470 
  4471 *** HOL-Complex ***
  4472 
  4473 * Theory RealDef: better support for embedding natural numbers and
  4474 integers in the reals.
  4475 
  4476 The following theorems have been eliminated or modified
  4477 (INCOMPATIBILITY):
  4478 
  4479   exp_ge_add_one_self  now requires no hypotheses
  4480   real_of_int_add      reversed direction of equality (use [symmetric])
  4481   real_of_int_minus    reversed direction of equality (use [symmetric])
  4482   real_of_int_diff     reversed direction of equality (use [symmetric])
  4483   real_of_int_mult     reversed direction of equality (use [symmetric])
  4484 
  4485 * Theory RComplete: expanded support for floor and ceiling functions.
  4486 
  4487 * Theory Ln is new, with properties of the natural logarithm
  4488 
  4489 * Hyperreal: There is a new type constructor "star" for making
  4490 nonstandard types.  The old type names are now type synonyms:
  4491 
  4492   hypreal = real star
  4493   hypnat = nat star
  4494   hcomplex = complex star
  4495 
  4496 * Hyperreal: Many groups of similarly-defined constants have been
  4497 replaced by polymorphic versions (INCOMPATIBILITY):
  4498 
  4499   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  4500 
  4501   starset      <-- starsetNat, starsetC
  4502   *s*          <-- *sNat*, *sc*
  4503   starset_n    <-- starsetNat_n, starsetC_n
  4504   *sn*         <-- *sNatn*, *scn*
  4505   InternalSets <-- InternalNatSets, InternalCSets
  4506 
  4507   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  4508   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  4509   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  4510   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  4511   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  4512 
  4513 * Hyperreal: Many type-specific theorems have been removed in favor of
  4514 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  4515 
  4516   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  4517   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  4518   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  4519   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  4520   right_minus <-- hypreal_add_minus
  4521   left_minus <-- {hypreal,hcomplex}_add_minus_left
  4522   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  4523   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  4524   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  4525   mult_1_right <-- hcomplex_mult_one_right
  4526   mult_zero_left <-- hcomplex_mult_zero_left
  4527   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  4528   right_distrib <-- hypnat_add_mult_distrib2
  4529   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  4530   right_inverse <-- hypreal_mult_inverse
  4531   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  4532   order_refl <-- {hypreal,hypnat}_le_refl
  4533   order_trans <-- {hypreal,hypnat}_le_trans
  4534   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  4535   order_less_le <-- {hypreal,hypnat}_less_le
  4536   linorder_linear <-- {hypreal,hypnat}_le_linear
  4537   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  4538   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  4539   add_nonneg_nonneg <-- hypreal_le_add_order
  4540 
  4541 * Hyperreal: Separate theorems having to do with type-specific
  4542 versions of constants have been merged into theorems that apply to the
  4543 new polymorphic constants (INCOMPATIBILITY):
  4544 
  4545   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  4546   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  4547   STAR_Un <-- {STAR,NatStar,STARC}_Un
  4548   STAR_Int <-- {STAR,NatStar,STARC}_Int
  4549   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  4550   STAR_subset <-- {STAR,NatStar,STARC}_subset
  4551   STAR_mem <-- {STAR,NatStar,STARC}_mem
  4552   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  4553   STAR_diff <-- {STAR,STARC}_diff
  4554   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  4555     STARC_hcomplex_of_complex}_image_subset
  4556   starset_n_Un <-- starset{Nat,C}_n_Un
  4557   starset_n_Int <-- starset{Nat,C}_n_Int
  4558   starset_n_Compl <-- starset{Nat,C}_n_Compl
  4559   starset_n_diff <-- starset{Nat,C}_n_diff
  4560   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  4561   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  4562   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  4563   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  4564   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  4565   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  4566   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  4567   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  4568   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  4569   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  4570   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  4571   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  4572   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  4573   starfun_diff <-- starfun{C,RC,CR}_diff
  4574   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  4575   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  4576   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  4577   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  4578   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  4579   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  4580   starfun_Id <-- starfunC_Id
  4581   starfun_approx <-- starfun{Nat,CR}_approx
  4582   starfun_capprox <-- starfun{C,RC}_capprox
  4583   starfun_abs <-- starfunNat_rabs
  4584   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  4585   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  4586   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  4587   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  4588   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  4589   starfun_add_approx <-- starfunCR_add_approx
  4590   starfun_inverse_inverse <-- starfunC_inverse_inverse
  4591   starfun_divide <-- starfun{C,CR,RC}_divide
  4592   starfun_n <-- starfun{Nat,C}_n
  4593   starfun_n_mult <-- starfun{Nat,C}_n_mult
  4594   starfun_n_add <-- starfun{Nat,C}_n_add
  4595   starfun_n_add_minus <-- starfunNat_n_add_minus
  4596   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  4597   starfun_n_minus <-- starfun{Nat,C}_n_minus
  4598   starfun_n_eq <-- starfun{Nat,C}_n_eq
  4599 
  4600   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  4601   star_n_minus <-- {hypreal,hcomplex}_minus
  4602   star_n_diff <-- {hypreal,hcomplex}_diff
  4603   star_n_mult <-- {hypreal,hcomplex}_mult
  4604   star_n_inverse <-- {hypreal,hcomplex}_inverse
  4605   star_n_le <-- {hypreal,hypnat}_le
  4606   star_n_less <-- {hypreal,hypnat}_less
  4607   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  4608   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  4609   star_n_abs <-- hypreal_hrabs
  4610   star_n_divide <-- hcomplex_divide
  4611 
  4612   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  4613   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  4614   star_of_diff <-- hypreal_of_real_diff
  4615   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  4616   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  4617   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  4618   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  4619   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  4620   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  4621   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  4622   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  4623   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  4624   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  4625   star_of_number_of <-- {hypreal,hcomplex}_number_of
  4626   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  4627   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  4628   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  4629   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  4630   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  4631   star_of_power <-- hypreal_of_real_power
  4632   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  4633 
  4634 * Hyperreal: new method "transfer" that implements the transfer
  4635 principle of nonstandard analysis. With a subgoal that mentions
  4636 nonstandard types like "'a star", the command "apply transfer"
  4637 replaces it with an equivalent one that mentions only standard types.
  4638 To be successful, all free variables must have standard types; non-
  4639 standard variables must have explicit universal quantifiers.
  4640 
  4641 * Hyperreal: A theory of Taylor series.
  4642 
  4643 
  4644 *** HOLCF ***
  4645 
  4646 * Discontinued special version of 'constdefs' (which used to support
  4647 continuous functions) in favor of the general Pure one with full
  4648 type-inference.
  4649 
  4650 * New simplification procedure for solving continuity conditions; it
  4651 is much faster on terms with many nested lambda abstractions (cubic
  4652 instead of exponential time).
  4653 
  4654 * New syntax for domain package: selector names are now optional.
  4655 Parentheses should be omitted unless argument is lazy, for example:
  4656 
  4657   domain 'a stream = cons "'a" (lazy "'a stream")
  4658 
  4659 * New command 'fixrec' for defining recursive functions with pattern
  4660 matching; defining multiple functions with mutual recursion is also
  4661 supported.  Patterns may include the constants cpair, spair, up, sinl,
  4662 sinr, or any data constructor defined by the domain package. The given
  4663 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  4664 syntax and examples.
  4665 
  4666 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  4667 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  4668 but the proof obligation additionally includes an admissibility
  4669 requirement. The packages generate instances of class cpo or pcpo,
  4670 with continuity and strictness theorems for Rep and Abs.
  4671 
  4672 * HOLCF: Many theorems have been renamed according to a more standard naming
  4673 scheme (INCOMPATIBILITY):
  4674 
  4675   foo_inject:  "foo$x = foo$y ==> x = y"
  4676   foo_eq:      "(foo$x = foo$y) = (x = y)"
  4677   foo_less:    "(foo$x << foo$y) = (x << y)"
  4678   foo_strict:  "foo$UU = UU"
  4679   foo_defined: "... ==> foo$x ~= UU"
  4680   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  4681 
  4682 
  4683 *** ZF ***
  4684 
  4685 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  4686 including the First Isomorphism Theorem (on quotienting by the kernel
  4687 of a homomorphism).
  4688 
  4689 * ZF/Simplifier: install second copy of type solver that actually
  4690 makes use of TC rules declared to Isar proof contexts (or locales);
  4691 the old version is still required for ML proof scripts.
  4692 
  4693 
  4694 *** Cube ***
  4695 
  4696 * Converted to Isar theory format; use locales instead of axiomatic
  4697 theories.
  4698 
  4699 
  4700 *** ML ***
  4701 
  4702 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  4703 for ||>, ||>>, |>>,
  4704 
  4705 * Pure/library.ML no longer defines its own option datatype, but uses
  4706 that of the SML basis, which has constructors NONE and SOME instead of
  4707 None and Some, as well as exception Option.Option instead of OPTION.
  4708 The functions the, if_none, is_some, is_none have been adapted
  4709 accordingly, while Option.map replaces apsome.
  4710 
  4711 * Pure/library.ML: the exception LIST has been given up in favour of
  4712 the standard exceptions Empty and Subscript, as well as
  4713 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  4714 superceded by the standard hd and tl functions etc.
  4715 
  4716 A number of basic list functions are no longer exported to the ML
  4717 toplevel, as they are variants of predefined functions.  The following
  4718 suggests how one can translate existing code:
  4719 
  4720     rev_append xs ys = List.revAppend (xs, ys)
  4721     nth_elem (i, xs) = List.nth (xs, i)
  4722     last_elem xs = List.last xs
  4723     flat xss = List.concat xss
  4724     seq fs = List.app fs
  4725     partition P xs = List.partition P xs
  4726     mapfilter f xs = List.mapPartial f xs
  4727 
  4728 * Pure/library.ML: several combinators for linear functional
  4729 transformations, notably reverse application and composition:
  4730 
  4731   x |> f                f #> g
  4732   (x, y) |-> f          f #-> g
  4733 
  4734 * Pure/library.ML: introduced/changed precedence of infix operators:
  4735 
  4736   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  4737   infix 2 ?;
  4738   infix 3 o oo ooo oooo;
  4739   infix 4 ~~ upto downto;
  4740 
  4741 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  4742 infix operators.
  4743 
  4744 * Pure/library.ML: natural list combinators fold, fold_rev, and
  4745 fold_map support linear functional transformations and nesting.  For
  4746 example:
  4747 
  4748   fold f [x1, ..., xN] y =
  4749     y |> f x1 |> ... |> f xN
  4750 
  4751   (fold o fold) f [xs1, ..., xsN] y =
  4752     y |> fold f xs1 |> ... |> fold f xsN
  4753 
  4754   fold f [x1, ..., xN] =
  4755     f x1 #> ... #> f xN
  4756 
  4757   (fold o fold) f [xs1, ..., xsN] =
  4758     fold f xs1 #> ... #> fold f xsN
  4759 
  4760 * Pure/library.ML: the following selectors on type 'a option are
  4761 available:
  4762 
  4763   the:               'a option -> 'a  (*partial*)
  4764   these:             'a option -> 'a  where 'a = 'b list
  4765   the_default: 'a -> 'a option -> 'a
  4766   the_list:          'a option -> 'a list
  4767 
  4768 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  4769 basic operations for association lists, following natural argument
  4770 order; moreover the explicit equality predicate passed here avoids
  4771 potentially expensive polymorphic runtime equality checks.
  4772 The old functions may be expressed as follows:
  4773 
  4774   assoc = uncurry (AList.lookup (op =))
  4775   assocs = these oo AList.lookup (op =)
  4776   overwrite = uncurry (AList.update (op =)) o swap
  4777 
  4778 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  4779 
  4780   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  4781   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  4782 
  4783 replacing make_keylist and keyfilter (occassionally used)
  4784 Naive rewrites:
  4785 
  4786   make_keylist = AList.make
  4787   keyfilter = AList.find (op =)
  4788 
  4789 * eq_fst and eq_snd now take explicit equality parameter, thus
  4790   avoiding eqtypes. Naive rewrites:
  4791 
  4792     eq_fst = eq_fst (op =)
  4793     eq_snd = eq_snd (op =)
  4794 
  4795 * Removed deprecated apl and apr (rarely used).
  4796   Naive rewrites:
  4797 
  4798     apl (n, op) =>>= curry op n
  4799     apr (op, m) =>>= fn n => op (n, m)
  4800 
  4801 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  4802 provides a reasonably efficient light-weight implementation of sets as
  4803 lists.
  4804 
  4805 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  4806 few new operations; existing lookup and update are now curried to
  4807 follow natural argument order (for use with fold etc.);
  4808 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  4809 
  4810 * Pure/General: output via the Isabelle channels of
  4811 writeln/warning/error etc. is now passed through Output.output, with a
  4812 hook for arbitrary transformations depending on the print_mode
  4813 (cf. Output.add_mode -- the first active mode that provides a output
  4814 function wins).  Already formatted output may be embedded into further
  4815 text via Output.raw; the result of Pretty.string_of/str_of and derived
  4816 functions (string_of_term/cterm/thm etc.) is already marked raw to
  4817 accommodate easy composition of diagnostic messages etc.  Programmers
  4818 rarely need to care about Output.output or Output.raw at all, with
  4819 some notable exceptions: Output.output is required when bypassing the
  4820 standard channels (writeln etc.), or in token translations to produce
  4821 properly formatted results; Output.raw is required when capturing
  4822 already output material that will eventually be presented to the user
  4823 a second time.  For the default print mode, both Output.output and
  4824 Output.raw have no effect.
  4825 
  4826 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  4827 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  4828 cumulative results are displayed at the end of a batch session.
  4829 
  4830 * Pure/General: File.sysify_path and File.quote_sysify path have been
  4831 replaced by File.platform_path and File.shell_path (with appropriate
  4832 hooks).  This provides a clean interface for unusual systems where the
  4833 internal and external process view of file names are different.
  4834 
  4835 * Pure: more efficient orders for basic syntactic entities: added
  4836 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  4837 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  4838 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  4839 orders now -- potential INCOMPATIBILITY for code that depends on a
  4840 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  4841 Library.sort_strings on result).
  4842 
  4843 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  4844 fold_types traverse types/terms from left to right, observing natural
  4845 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  4846 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  4847 
  4848 * Pure: name spaces have been refined, with significant changes of the
  4849 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  4850 to extern(_table).  The plain name entry path is superceded by a
  4851 general 'naming' context, which also includes the 'policy' to produce
  4852 a fully qualified name and external accesses of a fully qualified
  4853 name; NameSpace.extend is superceded by context dependent
  4854 Sign.declare_name.  Several theory and proof context operations modify
  4855 the naming context.  Especially note Theory.restore_naming and
  4856 ProofContext.restore_naming to get back to a sane state; note that
  4857 Theory.add_path is no longer sufficient to recover from
  4858 Theory.absolute_path in particular.
  4859 
  4860 * Pure: new flags short_names (default false) and unique_names
  4861 (default true) for controlling output of qualified names.  If
  4862 short_names is set, names are printed unqualified.  If unique_names is
  4863 reset, the name prefix is reduced to the minimum required to achieve
  4864 the original result when interning again, even if there is an overlap
  4865 with earlier declarations.
  4866 
  4867 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  4868 now 'extend', and 'merge' gets an additional Pretty.pp argument
  4869 (useful for printing error messages).  INCOMPATIBILITY.
  4870 
  4871 * Pure: major reorganization of the theory context.  Type Sign.sg and
  4872 Theory.theory are now identified, referring to the universal
  4873 Context.theory (see Pure/context.ML).  Actual signature and theory
  4874 content is managed as theory data.  The old code and interfaces were
  4875 spread over many files and structures; the new arrangement introduces
  4876 considerable INCOMPATIBILITY to gain more clarity:
  4877 
  4878   Context -- theory management operations (name, identity, inclusion,
  4879     parents, ancestors, merge, etc.), plus generic theory data;
  4880 
  4881   Sign -- logical signature and syntax operations (declaring consts,
  4882     types, etc.), plus certify/read for common entities;
  4883 
  4884   Theory -- logical theory operations (stating axioms, definitions,
  4885     oracles), plus a copy of logical signature operations (consts,
  4886     types, etc.); also a few basic management operations (Theory.copy,
  4887     Theory.merge, etc.)
  4888 
  4889 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  4890 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  4891 for convenience -- they merely return the theory.
  4892 
  4893 * Pure: type Type.tsig is superceded by theory in most interfaces.
  4894 
  4895 * Pure: the Isar proof context type is already defined early in Pure
  4896 as Context.proof (note that ProofContext.context and Proof.context are
  4897 aliases, where the latter is the preferred name).  This enables other
  4898 Isabelle components to refer to that type even before Isar is present.
  4899 
  4900 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  4901 typeK, constK, axiomK, oracleK), but provide explicit operations for
  4902 any of these kinds.  For example, Sign.intern typeK is now
  4903 Sign.intern_type, Theory.hide_space Sign.typeK is now
  4904 Theory.hide_types.  Also note that former
  4905 Theory.hide_classes/types/consts are now
  4906 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  4907 internalize their arguments!  INCOMPATIBILITY.
  4908 
  4909 * Pure: get_thm interface (of PureThy and ProofContext) expects
  4910 datatype thmref (with constructors Name and NameSelection) instead of
  4911 plain string -- INCOMPATIBILITY;
  4912 
  4913 * Pure: cases produced by proof methods specify options, where NONE
  4914 means to remove case bindings -- INCOMPATIBILITY in
  4915 (RAW_)METHOD_CASES.
  4916 
  4917 * Pure: the following operations retrieve axioms or theorems from a
  4918 theory node or theory hierarchy, respectively:
  4919 
  4920   Theory.axioms_of: theory -> (string * term) list
  4921   Theory.all_axioms_of: theory -> (string * term) list
  4922   PureThy.thms_of: theory -> (string * thm) list
  4923   PureThy.all_thms_of: theory -> (string * thm) list
  4924 
  4925 * Pure: print_tac now outputs the goal through the trace channel.
  4926 
  4927 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  4928 Reference Toplevel.debug (default false) controls detailed printing
  4929 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  4930 controls execution profiling -- set to 1 for time and 2 for space
  4931 (both increase the runtime).
  4932 
  4933 * Isar session: The initial use of ROOT.ML is now always timed,
  4934 i.e. the log will show the actual process times, in contrast to the
  4935 elapsed wall-clock time that the outer shell wrapper produces.
  4936 
  4937 * Simplifier: improved handling of bound variables (nameless
  4938 representation, avoid allocating new strings).  Simprocs that invoke
  4939 the Simplifier recursively should use Simplifier.inherit_bounds to
  4940 avoid local name clashes.  Failure to do so produces warnings
  4941 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  4942 for further details.
  4943 
  4944 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  4945 bindings for all theorems stored within a given theory; this may help
  4946 in porting non-Isar theories to Isar ones, while keeping ML proof
  4947 scripts for the time being.
  4948 
  4949 * ML operator HTML.with_charset specifies the charset begin used for
  4950 generated HTML files.  For example:
  4951 
  4952   HTML.with_charset "utf-8" use_thy "Hebrew";
  4953   HTML.with_charset "utf-8" use_thy "Chinese";
  4954 
  4955 
  4956 *** System ***
  4957 
  4958 * Allow symlinks to all proper Isabelle executables (Isabelle,
  4959 isabelle, isatool etc.).
  4960 
  4961 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  4962 isatool doc, isatool mkdir, display_drafts etc.).
  4963 
  4964 * isatool usedir: option -f allows specification of the ML file to be
  4965 used by Isabelle; default is ROOT.ML.
  4966 
  4967 * New isatool version outputs the version identifier of the Isabelle
  4968 distribution being used.
  4969 
  4970 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  4971 (containing Boolean satisfiability problems) into Isabelle/HOL
  4972 theories.
  4973 
  4974 
  4975 
  4976 New in Isabelle2004 (April 2004)
  4977 --------------------------------
  4978 
  4979 *** General ***
  4980 
  4981 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  4982   Replaces linorder.ML.
  4983 
  4984 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  4985   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  4986   (\<a>...\<z>), are now considered normal letters, and can therefore
  4987   be used anywhere where an ASCII letter (a...zA...Z) has until
  4988   now. COMPATIBILITY: This obviously changes the parsing of some
  4989   terms, especially where a symbol has been used as a binder, say
  4990   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  4991   as an identifier.  Fix it by inserting a space around former
  4992   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  4993   existing theory and ML files.
  4994 
  4995 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  4996 
  4997 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  4998   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  4999   a normal (but invisible) letter. For multiple letter subscripts repeat
  5000   \<^isub> like this: x\<^isub>1\<^isub>2.
  5001 
  5002 * Pure: There are now sub-/superscripts that can span more than one
  5003   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5004   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5005   superscript. The new control characters are not identifier parts.
  5006 
  5007 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5008   content of "..." to the latex file instead of \isacntrl... . The "..."
  5009   may consist of any printable characters excluding the end bracket >.
  5010 
  5011 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5012   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5013   declare constants "final", which prevents their being given a definition
  5014   later.  It is useful for constants whose behaviour is fixed axiomatically
  5015   rather than definitionally, such as the meta-logic connectives.
  5016 
  5017 * Pure: 'instance' now handles general arities with general sorts
  5018   (i.e. intersections of classes),
  5019 
  5020 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5021   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5022   It can be changed to alter the colors/layout of generated pages.
  5023 
  5024 
  5025 *** Isar ***
  5026 
  5027 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5028   cut_tac, subgoal_tac and thin_tac:
  5029   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5030     locales are no longer forced to write Isar proof scripts.
  5031     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5032     emulations.
  5033   - INCOMPATIBILITY: names of variables to be instantiated may no
  5034     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5035     This is consistent with the instantiation attribute "where".
  5036 
  5037 * Attributes "where" and "of":
  5038   - Now take type variables of instantiated theorem into account when reading
  5039     the instantiation string.  This fixes a bug that caused instantiated
  5040     theorems to have too special types in some circumstances.
  5041   - "where" permits explicit instantiations of type variables.
  5042 
  5043 * Calculation commands "moreover" and "also" no longer interfere with
  5044   current facts ("this"), admitting arbitrary combinations with "then"
  5045   and derived forms.
  5046 
  5047 * Locales:
  5048   - Goal statements involving the context element "includes" no longer
  5049     generate theorems with internal delta predicates (those ending on
  5050     "_axioms") in the premise.
  5051     Resolve particular premise with <locale>.intro to obtain old form.
  5052   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5053     specification and "includes" elements in goal statement.
  5054   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5055     [intro?] and [elim?] (respectively) by default.
  5056   - Experimental command for instantiation of locales in proof contexts:
  5057         instantiate <label>[<attrs>]: <loc>
  5058     Instantiates locale <loc> and adds all its theorems to the current context
  5059     taking into account their attributes.  Label and attrs are optional
  5060     modifiers, like in theorem declarations.  If present, names of
  5061     instantiated theorems are qualified with <label>, and the attributes
  5062     <attrs> are applied after any attributes these theorems might have already.
  5063       If the locale has assumptions, a chained fact of the form
  5064     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5065     are derived.  The command does not support old-style locales declared
  5066     with "locale (open)".
  5067       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5068 
  5069 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5070   (Isar) contexts.
  5071 
  5072 
  5073 *** HOL ***
  5074 
  5075 * Proof import: new image HOL4 contains the imported library from
  5076   the HOL4 system with about 2500 theorems. It is imported by
  5077   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5078   can be used like any other Isabelle image.  See
  5079   HOL/Import/HOL/README for more information.
  5080 
  5081 * Simplifier:
  5082   - Much improved handling of linear and partial orders.
  5083     Reasoners for linear and partial orders are set up for type classes
  5084     "linorder" and "order" respectively, and are added to the default simpset
  5085     as solvers.  This means that the simplifier can build transitivity chains
  5086     to solve goals from the assumptions.
  5087   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5088     of blast or auto after simplification become unnecessary because the goal
  5089     is solved by simplification already.
  5090 
  5091 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5092     all proved in axiomatic type classes for semirings, rings and fields.
  5093 
  5094 * Numerics:
  5095   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5096     now formalized using the Ring_and_Field theory mentioned above.
  5097   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5098     than before, because now they are set up once in a generic manner.
  5099   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5100     Look for the general versions in Ring_and_Field (and Power if they concern
  5101     exponentiation).
  5102 
  5103 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5104 
  5105 * Records:
  5106   - Record types are now by default printed with their type abbreviation
  5107     instead of the list of all field types. This can be configured via
  5108     the reference "print_record_type_abbr".
  5109   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5110     (not enabled by default).
  5111   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5112     EX x. x = sel r to True (not enabled by default).
  5113   - Tactic "record_split_simp_tac" to split and simplify records added.
  5114 
  5115 * 'specification' command added, allowing for definition by
  5116   specification.  There is also an 'ax_specification' command that
  5117   introduces the new constants axiomatically.
  5118 
  5119 * arith(_tac) is now able to generate counterexamples for reals as well.
  5120 
  5121 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5122 
  5123 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5124   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5125 
  5126 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5127   matrix theory to linear programming.
  5128 
  5129 * Unions and Intersections:
  5130   The latex output syntax of UN and INT has been changed
  5131   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5132   i.e. the index formulae has become a subscript.
  5133   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5134 
  5135 * Unions and Intersections over Intervals:
  5136   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5137   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5138   like in normal math, and corresponding versions for < and for intersection.
  5139 
  5140 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5141   lexicographic dictonary ordering has been added as "lexord".
  5142 
  5143 * ML: the legacy theory structures Int and List have been removed. They had
  5144   conflicted with ML Basis Library structures having the same names.
  5145 
  5146 * 'refute' command added to search for (finite) countermodels.  Only works
  5147   for a fragment of HOL.  The installation of an external SAT solver is
  5148   highly recommended.  See "HOL/Refute.thy" for details.
  5149 
  5150 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5151   formulae under an assignment of free variables to random values.
  5152   In contrast to 'refute', it can deal with inductive datatypes,
  5153   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5154   for examples.
  5155 
  5156 
  5157 *** HOLCF ***
  5158 
  5159 * Streams now come with concatenation and are part of the HOLCF image
  5160 
  5161 
  5162 
  5163 New in Isabelle2003 (May 2003)
  5164 ------------------------------
  5165 
  5166 *** General ***
  5167 
  5168 * Provers/simplifier:
  5169 
  5170   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5171     Assumptions are now subject to complete mutual simplification,
  5172     not just from left to right. The simplifier now preserves
  5173     the order of assumptions.
  5174 
  5175     Potential INCOMPATIBILITY:
  5176 
  5177     -- simp sometimes diverges where the old version did
  5178        not, e.g. invoking simp on the goal
  5179 
  5180         [| P (f x); y = x; f x = f y |] ==> Q
  5181 
  5182        now gives rise to the infinite reduction sequence
  5183 
  5184         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5185 
  5186        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5187        kind of problem.
  5188 
  5189     -- Tactics combining classical reasoner and simplification (such as auto)
  5190        are also affected by this change, because many of them rely on
  5191        simp. They may sometimes diverge as well or yield a different numbers
  5192        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5193        in case of problems. Sometimes subsequent calls to the classical
  5194        reasoner will fail because a preceeding call to the simplifier too
  5195        eagerly simplified the goal, e.g. deleted redundant premises.
  5196 
  5197   - The simplifier trace now shows the names of the applied rewrite rules
  5198 
  5199   - You can limit the number of recursive invocations of the simplifier
  5200     during conditional rewriting (where the simplifie tries to solve the
  5201     conditions before applying the rewrite rule):
  5202     ML "simp_depth_limit := n"
  5203     where n is an integer. Thus you can force termination where previously
  5204     the simplifier would diverge.
  5205 
  5206   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5207 
  5208   - No longer aborts on failed congruence proof.  Instead, the
  5209     congruence is ignored.
  5210 
  5211 * Pure: New generic framework for extracting programs from constructive
  5212   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5213   as HOL/Extraction for some case studies.
  5214 
  5215 * Pure: The main goal of the proof state is no longer shown by default, only
  5216 the subgoals. This behaviour is controlled by a new flag.
  5217    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5218 (ML: Proof.show_main_goal).
  5219 
  5220 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5221 rules whose conclusion matches subgoal 1:
  5222       PG menu: Isabelle/Isar -> Show me -> matching rules
  5223 The rules are ordered by how closely they match the subgoal.
  5224 In particular, rules that solve a subgoal outright are displayed first
  5225 (or rather last, the way they are printed).
  5226 (ML: ProofGeneral.print_intros())
  5227 
  5228 * Pure: New flag trace_unify_fail causes unification to print
  5229 diagnostic information (PG: in trace buffer) when it fails. This is
  5230 useful for figuring out why single step proofs like rule, erule or
  5231 assumption failed.
  5232 
  5233 * Pure: Locale specifications now produce predicate definitions
  5234 according to the body of text (covering assumptions modulo local
  5235 definitions); predicate "loc_axioms" covers newly introduced text,
  5236 while "loc" is cumulative wrt. all included locale expressions; the
  5237 latter view is presented only on export into the global theory
  5238 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5239 on the old view without predicates;
  5240 
  5241 * Pure: predefined locales "var" and "struct" are useful for sharing
  5242 parameters (as in CASL, for example); just specify something like
  5243 ``var x + var y + struct M'' as import;
  5244 
  5245 * Pure: improved thms_containing: proper indexing of facts instead of
  5246 raw theorems; check validity of results wrt. current name space;
  5247 include local facts of proof configuration (also covers active
  5248 locales), cover fixed variables in index; may use "_" in term
  5249 specification; an optional limit for the number of printed facts may
  5250 be given (the default is 40);
  5251 
  5252 * Pure: disallow duplicate fact bindings within new-style theory files
  5253 (batch-mode only);
  5254 
  5255 * Provers: improved induct method: assumptions introduced by case
  5256 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5257 the goal statement); "foo" still refers to all facts collectively;
  5258 
  5259 * Provers: the function blast.overloaded has been removed: all constants
  5260 are regarded as potentially overloaded, which improves robustness in exchange
  5261 for slight decrease in efficiency;
  5262 
  5263 * Provers/linorder: New generic prover for transitivity reasoning over
  5264 linear orders.  Note: this prover is not efficient!
  5265 
  5266 * Isar: preview of problems to finish 'show' now produce an error
  5267 rather than just a warning (in interactive mode);
  5268 
  5269 
  5270 *** HOL ***
  5271 
  5272 * arith(_tac)
  5273 
  5274  - Produces a counter example if it cannot prove a goal.
  5275    Note that the counter example may be spurious if the goal is not a formula
  5276    of quantifier-free linear arithmetic.
  5277    In ProofGeneral the counter example appears in the trace buffer.
  5278 
  5279  - Knows about div k and mod k where k is a numeral of type nat or int.
  5280 
  5281  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5282    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5283    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5284 
  5285 * simp's arithmetic capabilities have been enhanced a bit: it now
  5286 takes ~= in premises into account (by performing a case split);
  5287 
  5288 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5289 are distributed over a sum of terms;
  5290 
  5291 * New tactic "trans_tac" and method "trans" instantiate
  5292 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5293 "<=", "<" and "=").
  5294 
  5295 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5296 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5297 
  5298 * 'typedef' command has new option "open" to suppress the set
  5299 definition;
  5300 
  5301 * functions Min and Max on finite sets have been introduced (theory
  5302 Finite_Set);
  5303 
  5304 * attribute [symmetric] now works for relations as well; it turns
  5305 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5306 
  5307 * induct over a !!-quantified statement (say !!x1..xn):
  5308   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5309 
  5310 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5311 %x. None. Warning: empty_def now refers to the previously hidden definition
  5312 of the empty set.
  5313 
  5314 * Algebra: formalization of classical algebra.  Intended as base for
  5315 any algebraic development in Isabelle.  Currently covers group theory
  5316 (up to Sylow's theorem) and ring theory (Universal Property of
  5317 Univariate Polynomials).  Contributions welcome;
  5318 
  5319 * GroupTheory: deleted, since its material has been moved to Algebra;
  5320 
  5321 * Complex: new directory of the complex numbers with numeric constants,
  5322 nonstandard complex numbers, and some complex analysis, standard and
  5323 nonstandard (Jacques Fleuriot);
  5324 
  5325 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  5326 
  5327 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  5328 Fleuriot);
  5329 
  5330 * Real/HahnBanach: updated and adapted to locales;
  5331 
  5332 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  5333 Gray and Kramer);
  5334 
  5335 * UNITY: added the Meier-Sanders theory of progress sets;
  5336 
  5337 * MicroJava: bytecode verifier and lightweight bytecode verifier
  5338 as abstract algorithms, instantiated to the JVM;
  5339 
  5340 * Bali: Java source language formalization. Type system, operational
  5341 semantics, axiomatic semantics. Supported language features:
  5342 classes, interfaces, objects,virtual methods, static methods,
  5343 static/instance fields, arrays, access modifiers, definite
  5344 assignment, exceptions.
  5345 
  5346 
  5347 *** ZF ***
  5348 
  5349 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  5350 universe, etc.);
  5351 
  5352 * Main ZF: virtually all theories converted to new-style format;
  5353 
  5354 
  5355 *** ML ***
  5356 
  5357 * Pure: Tactic.prove provides sane interface for internal proofs;
  5358 omits the infamous "standard" operation, so this is more appropriate
  5359 than prove_goalw_cterm in many situations (e.g. in simprocs);
  5360 
  5361 * Pure: improved error reporting of simprocs;
  5362 
  5363 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  5364 up simprocs;
  5365 
  5366 
  5367 *** Document preparation ***
  5368 
  5369 * uses \par instead of \\ for line breaks in theory text. This may
  5370 shift some page breaks in large documents. To get the old behaviour
  5371 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  5372 
  5373 * minimized dependencies of isabelle.sty and isabellesym.sty on
  5374 other packages
  5375 
  5376 * \<euro> now needs package babel/greek instead of marvosym (which
  5377 broke \Rightarrow)
  5378 
  5379 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  5380 textcomp package)
  5381 
  5382 
  5383 
  5384 New in Isabelle2002 (March 2002)
  5385 --------------------------------
  5386 
  5387 *** Document preparation ***
  5388 
  5389 * greatly simplified document preparation setup, including more
  5390 graceful interpretation of isatool usedir -i/-d/-D options, and more
  5391 instructive isatool mkdir; users should basically be able to get
  5392 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  5393 users may run a separate document processing stage manually like this:
  5394 "isatool usedir -D output HOL Test && isatool document Test/output";
  5395 
  5396 * theory dependency graph may now be incorporated into documents;
  5397 isatool usedir -g true will produce session_graph.eps/.pdf for use
  5398 with \includegraphics of LaTeX;
  5399 
  5400 * proper spacing of consecutive markup elements, especially text
  5401 blocks after section headings;
  5402 
  5403 * support bold style (for single symbols only), input syntax is like
  5404 this: "\<^bold>\<alpha>" or "\<^bold>A";
  5405 
  5406 * \<bullet> is now output as bold \cdot by default, which looks much
  5407 better in printed text;
  5408 
  5409 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  5410 note that these symbols are currently unavailable in Proof General /
  5411 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  5412 
  5413 * isatool latex no longer depends on changed TEXINPUTS, instead
  5414 isatool document copies the Isabelle style files to the target
  5415 location;
  5416 
  5417 
  5418 *** Isar ***
  5419 
  5420 * Pure/Provers: improved proof by cases and induction;
  5421   - 'case' command admits impromptu naming of parameters (such as
  5422     "case (Suc n)");
  5423   - 'induct' method divinates rule instantiation from the inductive
  5424     claim; no longer requires excessive ?P bindings for proper
  5425     instantiation of cases;
  5426   - 'induct' method properly enumerates all possibilities of set/type
  5427     rules; as a consequence facts may be also passed through *type*
  5428     rules without further ado;
  5429   - 'induct' method now derives symbolic cases from the *rulified*
  5430     rule (before it used to rulify cases stemming from the internal
  5431     atomized version); this means that the context of a non-atomic
  5432     statement becomes is included in the hypothesis, avoiding the
  5433     slightly cumbersome show "PROP ?case" form;
  5434   - 'induct' may now use elim-style induction rules without chaining
  5435     facts, using ``missing'' premises from the goal state; this allows
  5436     rules stemming from inductive sets to be applied in unstructured
  5437     scripts, while still benefitting from proper handling of non-atomic
  5438     statements; NB: major inductive premises need to be put first, all
  5439     the rest of the goal is passed through the induction;
  5440   - 'induct' proper support for mutual induction involving non-atomic
  5441     rule statements (uses the new concept of simultaneous goals, see
  5442     below);
  5443   - append all possible rule selections, but only use the first
  5444     success (no backtracking);
  5445   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  5446   - undeclared rule case names default to numbers 1, 2, 3, ...;
  5447   - added 'print_induct_rules' (covered by help item in recent Proof
  5448     General versions);
  5449   - moved induct/cases attributes to Pure, methods to Provers;
  5450   - generic method setup instantiated for FOL and HOL;
  5451 
  5452 * Pure: support multiple simultaneous goal statements, for example
  5453 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  5454 meta-level mechanism, this acts as if several individual goals had
  5455 been stated separately; in particular common proof methods need to be
  5456 repeated in order to cover all claims; note that a single elimination
  5457 step is *not* sufficient to establish the two conjunctions, so this
  5458 fails:
  5459 
  5460   assume "A & B" then have A and B ..   (*".." fails*)
  5461 
  5462 better use "obtain" in situations as above; alternative refer to
  5463 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  5464 
  5465 * Pure: proper integration with ``locales''; unlike the original
  5466 version by Florian Kammller, Isar locales package high-level proof
  5467 contexts rather than raw logical ones (e.g. we admit to include
  5468 attributes everywhere); operations on locales include merge and
  5469 rename; support for implicit arguments (``structures''); simultaneous
  5470 type-inference over imports and text; see also HOL/ex/Locales.thy for
  5471 some examples;
  5472 
  5473 * Pure: the following commands have been ``localized'', supporting a
  5474 target locale specification "(in name)": 'lemma', 'theorem',
  5475 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  5476 stored both within the locale and at the theory level (exported and
  5477 qualified by the locale name);
  5478 
  5479 * Pure: theory goals may now be specified in ``long'' form, with
  5480 ad-hoc contexts consisting of arbitrary locale elements. for example
  5481 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  5482 definitions may be given, too); the result is a meta-level rule with
  5483 the context elements being discharged in the obvious way;
  5484 
  5485 * Pure: new proof command 'using' allows to augment currently used
  5486 facts after a goal statement ('using' is syntactically analogous to
  5487 'apply', but acts on the goal's facts only); this allows chained facts
  5488 to be separated into parts given before and after a claim, as in
  5489 ``from a and b have C using d and e <proof>'';
  5490 
  5491 * Pure: renamed "antecedent" case to "rule_context";
  5492 
  5493 * Pure: new 'judgment' command records explicit information about the
  5494 object-logic embedding (used by several tools internally); no longer
  5495 use hard-wired "Trueprop";
  5496 
  5497 * Pure: added 'corollary' command;
  5498 
  5499 * Pure: fixed 'token_translation' command;
  5500 
  5501 * Pure: removed obsolete 'exported' attribute;
  5502 
  5503 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  5504 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  5505 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  5506 
  5507 * Pure: method 'atomize' presents local goal premises as object-level
  5508 statements (atomic meta-level propositions); setup controlled via
  5509 rewrite rules declarations of 'atomize' attribute; example
  5510 application: 'induct' method with proper rule statements in improper
  5511 proof *scripts*;
  5512 
  5513 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  5514 now consider the syntactic context of assumptions, giving a better
  5515 chance to get type-inference of the arguments right (this is
  5516 especially important for locales);
  5517 
  5518 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  5519 mode;
  5520 
  5521 * Pure/obtain: the formal conclusion "thesis", being marked as
  5522 ``internal'', may no longer be reference directly in the text;
  5523 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  5524 situations;
  5525 
  5526 * Pure: generic 'sym' attribute which declares a rule both as pure
  5527 'elim?' and for the 'symmetric' operation;
  5528 
  5529 * Pure: marginal comments ``--'' may now occur just anywhere in the
  5530 text; the fixed correlation with particular command syntax has been
  5531 discontinued;
  5532 
  5533 * Pure: new method 'rules' is particularly well-suited for proof
  5534 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  5535 but often produces more compact proof terms with less detours;
  5536 
  5537 * Pure/Provers/classical: simplified integration with pure rule
  5538 attributes and methods; the classical "intro?/elim?/dest?"
  5539 declarations coincide with the pure ones; the "rule" method no longer
  5540 includes classically swapped intros; "intro" and "elim" methods no
  5541 longer pick rules from the context; also got rid of ML declarations
  5542 AddXIs/AddXEs/AddXDs; all of this has some potential for
  5543 INCOMPATIBILITY;
  5544 
  5545 * Provers/classical: attribute 'swapped' produces classical inversions
  5546 of introduction rules;
  5547 
  5548 * Provers/simplifier: 'simplified' attribute may refer to explicit
  5549 rules instead of full simplifier context; 'iff' attribute handles
  5550 conditional rules;
  5551 
  5552 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  5553 
  5554 * HOL: 'recdef' now fails on unfinished automated proofs, use
  5555 "(permissive)" option to recover old behavior;
  5556 
  5557 * HOL: 'inductive' no longer features separate (collective) attributes
  5558 for 'intros' (was found too confusing);
  5559 
  5560 * HOL: properly declared induction rules less_induct and
  5561 wf_induct_rule;
  5562 
  5563 
  5564 *** HOL ***
  5565 
  5566 * HOL: moved over to sane numeral syntax; the new policy is as
  5567 follows:
  5568 
  5569   - 0 and 1 are polymorphic constants, which are defined on any
  5570   numeric type (nat, int, real etc.);
  5571 
  5572   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  5573   binary representation internally;
  5574 
  5575   - type nat has special constructor Suc, and generally prefers Suc 0
  5576   over 1::nat and Suc (Suc 0) over 2::nat;
  5577 
  5578 This change may cause significant problems of INCOMPATIBILITY; here
  5579 are some hints on converting existing sources:
  5580 
  5581   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  5582   entities, so expressions involving "-" (unary or binary minus) need
  5583   to be spaced properly;
  5584 
  5585   - existing occurrences of "1" may need to be constraint "1::nat" or
  5586   even replaced by Suc 0; similar for old "2";
  5587 
  5588   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  5589 
  5590   - remove all special provisions on numerals in proofs;
  5591 
  5592 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  5593 representation (depends on bin_arith_simps in the default context);
  5594 
  5595 * HOL: symbolic syntax for x^2 (numeral 2);
  5596 
  5597 * HOL: the class of all HOL types is now called "type" rather than
  5598 "term"; INCOMPATIBILITY, need to adapt references to this type class
  5599 in axclass/classes, instance/arities, and (usually rare) occurrences
  5600 in typings (of consts etc.); internally the class is called
  5601 "HOL.type", ML programs should refer to HOLogic.typeS;
  5602 
  5603 * HOL/record package improvements:
  5604   - new derived operations "fields" to build a partial record section,
  5605     "extend" to promote a fixed record to a record scheme, and
  5606     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  5607     declared as simp by default;
  5608   - shared operations ("more", "fields", etc.) now need to be always
  5609     qualified) --- potential INCOMPATIBILITY;
  5610   - removed "make_scheme" operations (use "make" with "extend") --
  5611     INCOMPATIBILITY;
  5612   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  5613   - provides cases/induct rules for use with corresponding Isar
  5614     methods (for concrete records, record schemes, concrete more
  5615     parts, and schematic more parts -- in that order);
  5616   - internal definitions directly based on a light-weight abstract
  5617     theory of product types over typedef rather than datatype;
  5618 
  5619 * HOL: generic code generator for generating executable ML code from
  5620 specifications; specific support for HOL constructs such as inductive
  5621 datatypes and sets, as well as recursive functions; can be invoked
  5622 via 'generate_code' theory section;
  5623 
  5624 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  5625 
  5626 * HOL: consolidated and renamed several theories.  In particular:
  5627         Ord.thy has been absorbed into HOL.thy
  5628         String.thy has been absorbed into List.thy
  5629 
  5630 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  5631 (beware of argument permutation!);
  5632 
  5633 * HOL: linorder_less_split superseded by linorder_cases;
  5634 
  5635 * HOL/List: "nodups" renamed to "distinct";
  5636 
  5637 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  5638 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  5639   - Ex_def has changed, now need to use some_eq_ex
  5640 
  5641 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  5642 in this (rare) case use:
  5643 
  5644   delSWrapper "split_all_tac"
  5645   addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
  5646 
  5647 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
  5648 MAY FAIL;
  5649 
  5650 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
  5651 Isabelle's type classes, ^ on functions and relations has too general
  5652 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be
  5653 necessary to attach explicit type constraints;
  5654 
  5655 * HOL/Relation: the prefix name of the infix "O" has been changed from
  5656 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been
  5657 renamed accordingly (eg "compI" -> "rel_compI").
  5658 
  5659 * HOL: syntax translations now work properly with numerals and records
  5660 expressions;
  5661 
  5662 * HOL: bounded abstraction now uses syntax "%" / "\<lambda>" instead
  5663 of "lam" -- INCOMPATIBILITY;
  5664 
  5665 * HOL: got rid of some global declarations (potential INCOMPATIBILITY
  5666 for ML tools): const "()" renamed "Product_Type.Unity", type "unit"
  5667 renamed "Product_Type.unit";
  5668 
  5669 * HOL: renamed rtrancl_into_rtrancl2 to converse_rtrancl_into_rtrancl
  5670 
  5671 * HOL: removed obsolete theorem "optionE" (use "option.exhaust", or
  5672 the "cases" method);
  5673 
  5674 * HOL/GroupTheory: group theory examples including Sylow's theorem (by
  5675 Florian Kammller);
  5676 
  5677 * HOL/IMP: updated and converted to new-style theory format; several
  5678 parts turned into readable document, with proper Isar proof texts and
  5679 some explanations (by Gerwin Klein);
  5680 
  5681 * HOL-Real: added Complex_Numbers (by Gertrud Bauer);
  5682 
  5683 * HOL-Hyperreal is now a logic image;
  5684 
  5685 
  5686 *** HOLCF ***
  5687 
  5688 * Isar: consts/constdefs supports mixfix syntax for continuous
  5689 operations;
  5690 
  5691 * Isar: domain package adapted to new-style theory format, e.g. see
  5692 HOLCF/ex/Dnat.thy;
  5693 
  5694 * theory Lift: proper use of rep_datatype lift instead of ML hacks --
  5695 potential INCOMPATIBILITY; now use plain induct_tac instead of former
  5696 lift.induct_tac, always use UU instead of Undef;
  5697 
  5698 * HOLCF/IMP: updated and converted to new-style theory;
  5699 
  5700 
  5701 *** ZF ***
  5702 
  5703 * Isar: proper integration of logic-specific tools and packages,
  5704 including theory commands '(co)inductive', '(co)datatype',
  5705 'rep_datatype', 'inductive_cases', as well as methods 'ind_cases',
  5706 'induct_tac', 'case_tac', and 'typecheck' (with attribute 'TC');
  5707 
  5708 * theory Main no longer includes AC; for the Axiom of Choice, base
  5709 your theory on Main_ZFC;
  5710 
  5711 * the integer library now covers quotients and remainders, with many
  5712 laws relating division to addition, multiplication, etc.;
  5713 
  5714 * ZF/UNITY: Chandy and Misra's UNITY is now available in ZF, giving a
  5715 typeless version of the formalism;
  5716 
  5717 * ZF/AC, Coind, IMP, Resid: updated and converted to new-style theory
  5718 format;
  5719 
  5720 * ZF/Induct: new directory for examples of inductive definitions,
  5721 including theory Multiset for multiset orderings; converted to
  5722 new-style theory format;
  5723 
  5724 * ZF: many new theorems about lists, ordinals, etc.;
  5725 
  5726 
  5727 *** General ***
  5728 
  5729 * Pure/kernel: meta-level proof terms (by Stefan Berghofer); reference
  5730 variable proof controls level of detail: 0 = no proofs (only oracle
  5731 dependencies), 1 = lemma dependencies, 2 = compact proof terms; see
  5732 also ref manual for further ML interfaces;
  5733 
  5734 * Pure/axclass: removed obsolete ML interface
  5735 goal_subclass/goal_arity;
  5736 
  5737 * Pure/syntax: new token syntax "num" for plain numerals (without "#"
  5738 of "xnum"); potential INCOMPATIBILITY, since -0, -1 etc. are now
  5739 separate tokens, so expressions involving minus need to be spaced
  5740 properly;
  5741 
  5742 * Pure/syntax: support non-oriented infixes, using keyword "infix"
  5743 rather than "infixl" or "infixr";
  5744 
  5745 * Pure/syntax: concrete syntax for dummy type variables admits genuine
  5746 sort constraint specifications in type inference; e.g. "x::_::foo"
  5747 ensures that the type of "x" is of sort "foo" (but not necessarily a
  5748 type variable);
  5749 
  5750 * Pure/syntax: print modes "type_brackets" and "no_type_brackets"
  5751 control output of nested => (types); the default behavior is
  5752 "type_brackets";
  5753 
  5754 * Pure/syntax: builtin parse translation for "_constify" turns valued
  5755 tokens into AST constants;
  5756 
  5757 * Pure/syntax: prefer later declarations of translations and print
  5758 translation functions; potential INCOMPATIBILITY: need to reverse
  5759 multiple declarations for same syntax element constant;
  5760 
  5761 * Pure/show_hyps reset by default (in accordance to existing Isar
  5762 practice);
  5763 
  5764 * Provers/classical: renamed addaltern to addafter, addSaltern to
  5765 addSafter;
  5766 
  5767 * Provers/clasimp: ``iff'' declarations now handle conditional rules
  5768 as well;
  5769 
  5770 * system: tested support for MacOS X; should be able to get Isabelle +
  5771 Proof General to work in a plain Terminal after installing Poly/ML
  5772 (e.g. from the Isabelle distribution area) and GNU bash alone
  5773 (e.g. from http://www.apple.com); full X11, XEmacs and X-Symbol
  5774 support requires further installations, e.g. from
  5775 http://fink.sourceforge.net/);
  5776 
  5777 * system: support Poly/ML 4.1.1 (able to manage larger heaps);
  5778 
  5779 * system: reduced base memory usage by Poly/ML (approx. 20 MB instead
  5780 of 40 MB), cf. ML_OPTIONS;
  5781 
  5782 * system: Proof General keywords specification is now part of the
  5783 Isabelle distribution (see etc/isar-keywords.el);
  5784 
  5785 * system: support for persistent Proof General sessions (refrain from
  5786 outdating all loaded theories on startup); user may create writable
  5787 logic images like this: ``isabelle -q HOL Test'';
  5788 
  5789 * system: smart selection of Isabelle process versus Isabelle
  5790 interface, accommodates case-insensitive file systems (e.g. HFS+); may
  5791 run both "isabelle" and "Isabelle" even if file names are badly
  5792 damaged (executable inspects the case of the first letter of its own
  5793 name); added separate "isabelle-process" and "isabelle-interface";
  5794 
  5795 * system: refrain from any attempt at filtering input streams; no
  5796 longer support ``8bit'' encoding of old isabelle font, instead proper
  5797 iso-latin characters may now be used; the related isatools
  5798 "symbolinput" and "nonascii" have disappeared as well;
  5799 
  5800 * system: removed old "xterm" interface (the print modes "xterm" and
  5801 "xterm_color" are still available for direct use in a suitable
  5802 terminal);
  5803 
  5804 
  5805 
  5806 New in Isabelle99-2 (February 2001)
  5807 -----------------------------------
  5808 
  5809 *** Overview of INCOMPATIBILITIES ***
  5810 
  5811 * HOL: please note that theories in the Library and elsewhere often use the
  5812 new-style (Isar) format; to refer to their theorems in an ML script you must
  5813 bind them to ML identifers by e.g.      val thm_name = thm "thm_name";
  5814 
  5815 * HOL: inductive package no longer splits induction rule aggressively,
  5816 but only as far as specified by the introductions given; the old
  5817 format may be recovered via ML function complete_split_rule or attribute
  5818 'split_rule (complete)';
  5819 
  5820 * HOL: induct renamed to lfp_induct, lfp_Tarski to lfp_unfold,
  5821 gfp_Tarski to gfp_unfold;
  5822 
  5823 * HOL: contrapos, contrapos2 renamed to contrapos_nn, contrapos_pp;
  5824 
  5825 * HOL: infix "dvd" now has priority 50 rather than 70 (because it is a
  5826 relation); infix "^^" has been renamed "``"; infix "``" has been
  5827 renamed "`"; "univalent" has been renamed "single_valued";
  5828 
  5829 * HOL/Real: "rinv" and "hrinv" replaced by overloaded "inverse"
  5830 operation;
  5831 
  5832 * HOLCF: infix "`" has been renamed "$"; the symbol syntax is \<cdot>;
  5833 
  5834 * Isar: 'obtain' no longer declares "that" fact as simp/intro;
  5835 
  5836 * Isar/HOL: method 'induct' now handles non-atomic goals; as a
  5837 consequence, it is no longer monotonic wrt. the local goal context
  5838 (which is now passed through the inductive cases);
  5839 
  5840 * Document preparation: renamed standard symbols \<ll> to \<lless> and
  5841 \<gg> to \<ggreater>;
  5842 
  5843 
  5844 *** Document preparation ***
  5845 
  5846 * \isabellestyle{NAME} selects version of Isabelle output (currently
  5847 available: are "it" for near math-mode best-style output, "sl" for
  5848 slanted text style, and "tt" for plain type-writer; if no
  5849 \isabellestyle command is given, output is according to slanted
  5850 type-writer);
  5851 
  5852 * support sub/super scripts (for single symbols only), input syntax is
  5853 like this: "A\<^sup>*" or "A\<^sup>\<star>";
  5854 
  5855 * some more standard symbols; see Appendix A of the system manual for
  5856 the complete list of symbols defined in isabellesym.sty;
  5857 
  5858 * improved isabelle style files; more abstract symbol implementation
  5859 (should now use \isamath{...} and \isatext{...} in custom symbol
  5860 definitions);
  5861 
  5862 * antiquotation @{goals} and @{subgoals} for output of *dynamic* goals
  5863 state; Note that presentation of goal states does not conform to
  5864 actual human-readable proof documents.  Please do not include goal
  5865 states into document output unless you really know what you are doing!
  5866 
  5867 * proper indentation of antiquoted output with proportional LaTeX
  5868 fonts;
  5869 
  5870 * no_document ML operator temporarily disables LaTeX document
  5871 generation;
  5872 
  5873 * isatool unsymbolize tunes sources for plain ASCII communication;
  5874 
  5875 
  5876 *** Isar ***
  5877 
  5878 * Pure: Isar now suffers initial goal statements to contain unbound
  5879 schematic variables (this does not conform to actual readable proof
  5880 documents, due to unpredictable outcome and non-compositional proof
  5881 checking); users who know what they are doing may use schematic goals
  5882 for Prolog-style synthesis of proven results;
  5883 
  5884 * Pure: assumption method (an implicit finishing) now handles actual
  5885 rules as well;
  5886 
  5887 * Pure: improved 'obtain' --- moved to Pure, insert "that" into
  5888 initial goal, declare "that" only as Pure intro (only for single
  5889 steps); the "that" rule assumption may now be involved in implicit
  5890 finishing, thus ".." becomes a feasible for trivial obtains;
  5891 
  5892 * Pure: default proof step now includes 'intro_classes'; thus trivial
  5893 instance proofs may be performed by "..";
  5894 
  5895 * Pure: ?thesis / ?this / "..." now work for pure meta-level
  5896 statements as well;
  5897 
  5898 * Pure: more robust selection of calculational rules;
  5899 
  5900 * Pure: the builtin notion of 'finished' goal now includes the ==-refl
  5901 rule (as well as the assumption rule);
  5902 
  5903 * Pure: 'thm_deps' command visualizes dependencies of theorems and
  5904 lemmas, using the graph browser tool;
  5905 
  5906 * Pure: predict failure of "show" in interactive mode;
  5907 
  5908 * Pure: 'thms_containing' now takes actual terms as arguments;
  5909 
  5910 * HOL: improved method 'induct' --- now handles non-atomic goals
  5911 (potential INCOMPATIBILITY); tuned error handling;
  5912 
  5913 * HOL: cases and induct rules now provide explicit hints about the
  5914 number of facts to be consumed (0 for "type" and 1 for "set" rules);
  5915 any remaining facts are inserted into the goal verbatim;
  5916 
  5917 * HOL: local contexts (aka cases) may now contain term bindings as
  5918 well; the 'cases' and 'induct' methods new provide a ?case binding for
  5919 the result to be shown in each case;
  5920 
  5921 * HOL: added 'recdef_tc' command;
  5922 
  5923 * isatool convert assists in eliminating legacy ML scripts;
  5924 
  5925 
  5926 *** HOL ***
  5927 
  5928 * HOL/Library: a collection of generic theories to be used together
  5929 with main HOL; the theory loader path already includes this directory
  5930 by default; the following existing theories have been moved here:
  5931 HOL/Induct/Multiset, HOL/Induct/Acc (as Accessible_Part), HOL/While
  5932 (as While_Combinator), HOL/Lex/Prefix (as List_Prefix);
  5933 
  5934 * HOL/Unix: "Some aspects of Unix file-system security", a typical
  5935 modelling and verification task performed in Isabelle/HOL +
  5936 Isabelle/Isar + Isabelle document preparation (by Markus Wenzel).
  5937 
  5938 * HOL/Algebra: special summation operator SUM no longer exists, it has
  5939 been replaced by setsum; infix 'assoc' now has priority 50 (like
  5940 'dvd'); axiom 'one_not_zero' has been moved from axclass 'ring' to
  5941 'domain', this makes the theory consistent with mathematical
  5942 literature;
  5943 
  5944 * HOL basics: added overloaded operations "inverse" and "divide"
  5945 (infix "/"), syntax for generic "abs" operation, generic summation
  5946 operator \<Sum>;
  5947 
  5948 * HOL/typedef: simplified package, provide more useful rules (see also
  5949 HOL/subset.thy);
  5950 
  5951 * HOL/datatype: induction rule for arbitrarily branching datatypes is
  5952 now expressed as a proper nested rule (old-style tactic scripts may
  5953 require atomize_strip_tac to cope with non-atomic premises);
  5954 
  5955 * HOL: renamed theory "Prod" to "Product_Type", renamed "split" rule
  5956 to "split_conv" (old name still available for compatibility);
  5957 
  5958 * HOL: improved concrete syntax for strings (e.g. allows translation
  5959 rules with string literals);
  5960 
  5961 * HOL-Real-Hyperreal: this extends HOL-Real with the hyperreals
  5962  and Fleuriot's mechanization of analysis, including the transcendental
  5963  functions for the reals;
  5964 
  5965 * HOL/Real, HOL/Hyperreal: improved arithmetic simplification;
  5966 
  5967 
  5968 *** CTT ***
  5969 
  5970 * CTT: x-symbol support for Pi, Sigma, -->, : (membership); note that
  5971 "lam" is displayed as TWO lambda-symbols
  5972 
  5973 * CTT: theory Main now available, containing everything (that is, Bool
  5974 and Arith);
  5975 
  5976 
  5977 *** General ***
  5978 
  5979 * Pure: the Simplifier has been implemented properly as a derived rule
  5980 outside of the actual kernel (at last!); the overall performance
  5981 penalty in practical applications is about 50%, while reliability of
  5982 the Isabelle inference kernel has been greatly improved;
  5983 
  5984 * print modes "brackets" and "no_brackets" control output of nested =>
  5985 (types) and ==> (props); the default behaviour is "brackets";
  5986 
  5987 * Provers: fast_tac (and friends) now handle actual object-logic rules
  5988 as assumptions as well;
  5989 
  5990 * system: support Poly/ML 4.0;
  5991 
  5992 * system: isatool install handles KDE version 1 or 2;
  5993 
  5994 
  5995 
  5996 New in Isabelle99-1 (October 2000)
  5997 ----------------------------------
  5998 
  5999 *** Overview of INCOMPATIBILITIES ***
  6000 
  6001 * HOL: simplification of natural numbers is much changed; to partly
  6002 recover the old behaviour (e.g. to prevent n+n rewriting to #2*n)
  6003 issue the following ML commands:
  6004 
  6005   Delsimprocs Nat_Numeral_Simprocs.cancel_numerals;
  6006   Delsimprocs [Nat_Numeral_Simprocs.combine_numerals];
  6007 
  6008 * HOL: simplification no longer dives into case-expressions; this is
  6009 controlled by "t.weak_case_cong" for each datatype t;
  6010 
  6011 * HOL: nat_less_induct renamed to less_induct;
  6012 
  6013 * HOL: systematic renaming of the SOME (Eps) rules, may use isatool
  6014 fixsome to patch .thy and .ML sources automatically;
  6015 
  6016   select_equality  -> some_equality
  6017   select_eq_Ex     -> some_eq_ex
  6018   selectI2EX       -> someI2_ex
  6019   selectI2         -> someI2
  6020   selectI          -> someI
  6021   select1_equality -> some1_equality
  6022   Eps_sym_eq       -> some_sym_eq_trivial
  6023   Eps_eq           -> some_eq_trivial
  6024 
  6025 * HOL: exhaust_tac on datatypes superceded by new generic case_tac;
  6026 
  6027 * HOL: removed obsolete theorem binding expand_if (refer to split_if
  6028 instead);
  6029 
  6030 * HOL: the recursion equations generated by 'recdef' are now called
  6031 f.simps instead of f.rules;
  6032 
  6033 * HOL: qed_spec_mp now also handles bounded ALL as well;
  6034 
  6035 * HOL: 0 is now overloaded, so the type constraint ":: nat" may
  6036 sometimes be needed;
  6037 
  6038 * HOL: the constant for "f``x" is now "image" rather than "op ``";
  6039 
  6040 * HOL: the constant for "f-``x" is now "vimage" rather than "op -``";
  6041 
  6042 * HOL: the disjoint sum is now "<+>" instead of "Plus"; the cartesian
  6043 product is now "<*>" instead of "Times"; the lexicographic product is
  6044 now "<*lex*>" instead of "**";
  6045 
  6046 * HOL: theory Sexp is now in HOL/Induct examples (it used to be part
  6047 of main HOL, but was unused); better use HOL's datatype package;
  6048 
  6049 * HOL: removed "symbols" syntax for constant "override" of theory Map;
  6050 the old syntax may be recovered as follows:
  6051 
  6052   syntax (symbols)
  6053     override  :: "('a ~=> 'b) => ('a ~=> 'b) => ('a ~=> 'b)"
  6054       (infixl "\\<oplus>" 100)
  6055 
  6056 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  6057 
  6058 * HOL/ML: even fewer consts are declared as global (see theories Ord,
  6059 Lfp, Gfp, WF); this only affects ML packages that refer to const names
  6060 internally;
  6061 
  6062 * HOL and ZF: syntax for quotienting wrt an equivalence relation
  6063 changed from A/r to A//r;
  6064 
  6065 * ZF: new treatment of arithmetic (nat & int) may break some old
  6066 proofs;
  6067 
  6068 * Isar: renamed some attributes (RS -> THEN, simplify -> simplified,
  6069 rulify -> rule_format, elimify -> elim_format, ...);
  6070 
  6071 * Isar/Provers: intro/elim/dest attributes changed; renamed
  6072 intro/intro!/intro!! flags to intro!/intro/intro? (in most cases, one
  6073 should have to change intro!! to intro? only); replaced "delrule" by
  6074 "rule del";
  6075 
  6076 * Isar/HOL: renamed "intrs" to "intros" in inductive definitions;
  6077 
  6078 * Provers: strengthened force_tac by using new first_best_tac;
  6079 
  6080 * LaTeX document preparation: several changes of isabelle.sty (see
  6081 lib/texinputs);
  6082 
  6083 
  6084 *** Document preparation ***
  6085 
  6086 * formal comments (text blocks etc.) in new-style theories may now
  6087 contain antiquotations of thm/prop/term/typ/text to be presented
  6088 according to latex print mode; concrete syntax is like this:
  6089 @{term[show_types] "f(x) = a + x"};
  6090 
  6091 * isatool mkdir provides easy setup of Isabelle session directories,
  6092 including proper document sources;
  6093 
  6094 * generated LaTeX sources are now deleted after successful run
  6095 (isatool document -c); may retain a copy somewhere else via -D option
  6096 of isatool usedir;
  6097 
  6098 * isatool usedir -D now lets isatool latex -o sty update the Isabelle
  6099 style files, achieving self-contained LaTeX sources and simplifying
  6100 LaTeX debugging;
  6101 
  6102 * old-style theories now produce (crude) LaTeX output as well;
  6103 
  6104 * browser info session directories are now self-contained (may be put
  6105 on WWW server seperately); improved graphs of nested sessions; removed
  6106 graph for 'all sessions';
  6107 
  6108 * several improvements in isabelle style files; \isabellestyle{it}
  6109 produces fake math mode output; \isamarkupheader is now \section by
  6110 default; see lib/texinputs/isabelle.sty etc.;
  6111 
  6112 
  6113 *** Isar ***
  6114 
  6115 * Isar/Pure: local results and corresponding term bindings are now
  6116 subject to Hindley-Milner polymorphism (similar to ML); this
  6117 accommodates incremental type-inference very nicely;
  6118 
  6119 * Isar/Pure: new derived language element 'obtain' supports
  6120 generalized existence reasoning;
  6121 
  6122 * Isar/Pure: new calculational elements 'moreover' and 'ultimately'
  6123 support accumulation of results, without applying any rules yet;
  6124 useful to collect intermediate results without explicit name
  6125 references, and for use with transitivity rules with more than 2
  6126 premises;
  6127 
  6128 * Isar/Pure: scalable support for case-analysis type proofs: new
  6129 'case' language element refers to local contexts symbolically, as
  6130 produced by certain proof methods; internally, case names are attached
  6131 to theorems as "tags";
  6132 
  6133 * Isar/Pure: theory command 'hide' removes declarations from
  6134 class/type/const name spaces;
  6135 
  6136 * Isar/Pure: theory command 'defs' supports option "(overloaded)" to
  6137 indicate potential overloading;
  6138 
  6139 * Isar/Pure: changed syntax of local blocks from {{ }} to { };
  6140 
  6141 * Isar/Pure: syntax of sorts made 'inner', i.e. have to write
  6142 "{a,b,c}" instead of {a,b,c};
  6143 
  6144 * Isar/Pure now provides its own version of intro/elim/dest
  6145 attributes; useful for building new logics, but beware of confusion
  6146 with the version in Provers/classical;
  6147 
  6148 * Isar/Pure: the local context of (non-atomic) goals is provided via
  6149 case name 'antecedent';
  6150 
  6151 * Isar/Pure: removed obsolete 'transfer' attribute (transfer of thms
  6152 to the current context is now done automatically);
  6153 
  6154 * Isar/Pure: theory command 'method_setup' provides a simple interface
  6155 for definining proof methods in ML;
  6156 
  6157 * Isar/Provers: intro/elim/dest attributes changed; renamed
  6158 intro/intro!/intro!! flags to intro!/intro/intro? (INCOMPATIBILITY, in
  6159 most cases, one should have to change intro!! to intro? only);
  6160 replaced "delrule" by "rule del";
  6161 
  6162 * Isar/Provers: new 'hypsubst' method, plain 'subst' method and
  6163 'symmetric' attribute (the latter supercedes [RS sym]);
  6164 
  6165 * Isar/Provers: splitter support (via 'split' attribute and 'simp'
  6166 method modifier); 'simp' method: 'only:' modifier removes loopers as
  6167 well (including splits);
  6168 
  6169 * Isar/Provers: Simplifier and Classical methods now support all kind
  6170 of modifiers used in the past, including 'cong', 'iff', etc.
  6171 
  6172 * Isar/Provers: added 'fastsimp' and 'clarsimp' methods (combination
  6173 of Simplifier and Classical reasoner);
  6174 
  6175 * Isar/HOL: new proof method 'cases' and improved version of 'induct'
  6176 now support named cases; major packages (inductive, datatype, primrec,
  6177 recdef) support case names and properly name parameters;
  6178 
  6179 * Isar/HOL: new transitivity rules for substitution in inequalities --
  6180 monotonicity conditions are extracted to be proven at end of
  6181 calculations;
  6182 
  6183 * Isar/HOL: removed 'case_split' thm binding, should use 'cases' proof
  6184 method anyway;
  6185 
  6186 * Isar/HOL: removed old expand_if = split_if; theorems if_splits =
  6187 split_if split_if_asm; datatype package provides theorems foo.splits =
  6188 foo.split foo.split_asm for each datatype;
  6189 
  6190 * Isar/HOL: tuned inductive package, rename "intrs" to "intros"
  6191 (potential INCOMPATIBILITY), emulation of mk_cases feature for proof
  6192 scripts: new 'inductive_cases' command and 'ind_cases' method; (Note:
  6193 use "(cases (simplified))" method in proper proof texts);
  6194 
  6195 * Isar/HOL: added global 'arith_split' attribute for 'arith' method;
  6196 
  6197 * Isar: names of theorems etc. may be natural numbers as well;
  6198 
  6199 * Isar: 'pr' command: optional arguments for goals_limit and
  6200 ProofContext.prems_limit; no longer prints theory contexts, but only
  6201 proof states;
  6202 
  6203 * Isar: diagnostic commands 'pr', 'thm', 'prop', 'term', 'typ' admit
  6204 additional print modes to be specified; e.g. "pr(latex)" will print
  6205 proof state according to the Isabelle LaTeX style;
  6206 
  6207 * Isar: improved support for emulating tactic scripts, including proof
  6208 methods 'rule_tac' etc., 'cut_tac', 'thin_tac', 'subgoal_tac',
  6209 'rename_tac', 'rotate_tac', 'tactic', and 'case_tac' / 'induct_tac'
  6210 (for HOL datatypes);
  6211 
  6212 * Isar: simplified (more robust) goal selection of proof methods: 1st
  6213 goal, all goals, or explicit goal specifier (tactic emulation); thus
  6214 'proof method scripts' have to be in depth-first order;
  6215 
  6216 * Isar: tuned 'let' syntax: replaced 'as' keyword by 'and';
  6217 
  6218 * Isar: removed 'help' command, which hasn't been too helpful anyway;
  6219 should instead use individual commands for printing items
  6220 (print_commands, print_methods etc.);
  6221 
  6222 * Isar: added 'nothing' --- the empty list of theorems;
  6223 
  6224 
  6225 *** HOL ***
  6226 
  6227 * HOL/MicroJava: formalization of a fragment of Java, together with a
  6228 corresponding virtual machine and a specification of its bytecode
  6229 verifier and a lightweight bytecode verifier, including proofs of
  6230 type-safety; by Gerwin Klein, Tobias Nipkow, David von Oheimb, and
  6231 Cornelia Pusch (see also the homepage of project Bali at
  6232 http://isabelle.in.tum.de/Bali/);
  6233 
  6234 * HOL/Algebra: new theory of rings and univariate polynomials, by
  6235 Clemens Ballarin;
  6236 
  6237 *